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e, and a size distribution ranging from a few micrometers to submicrometers.
Eu-VSOP and Gd have distinct spatial distributions in atherosclerotic plaques. While Eu-VSOP distribution is more cell-associated and might be used to monitor atherosclerotic plaque progression, Gd distribution indicates arterial calcification and might help in characterizing plaque vulnerability.
Eu-VSOP and Gd have distinct spatial distributions in atherosclerotic plaques. While Eu-VSOP distribution is more cell-associated and might be used to monitor atherosclerotic plaque progression, Gd distribution indicates arterial calcification and might help in characterizing plaque vulnerability.
Identifying predictors of positive surgical margins (PSM) and biochemical recurrence (BCR) after radical prostatectomy (RP) may assist clinicians in formulating prognosis. Aim of the study was to report the midterm oncologic outcomes, to identify the risk factors for PSM and BCR and assess the impact of the PSM on BCR-free survival following robot-assisted laparoscopic radical prostatectomy (RALP).
From 2005 to 2010, 1679 consecutive patients underwent transperitoneal RALP. Data was retrospectively collected by an independent statistical company and analyzed in 2014. Median postoperative follow-up was 33.5 mo. BCR was defined as any detectable serum prostate-specific antigen (PSA) ≥ 0.2ng/mL in two consecutive measurements. https://www.selleckchem.com/products/cb-839.html BCR-free survival was estimated using the Kaplan-Meier method. Univariate and multivariate analysis were applied to identify risk factors for PSM and BCR.
In pN0/pNx cancers, pathologic stage was pT2 in 1186 patients (71.8%), pT3 in 455 patients (27.6%), and pT4 in 11 patients (0.6%)ctor for high-quality oncologic outcomes.
Despite there being a considerable amount of published studies on robotic colorectal surgery (RCS) over the last few years, there is a lack of evidence regarding RCS training pathways. This study examines the short-term clinical outcomes of an international RCS training programme (the European Academy of Robotic Colorectal Surgery-EARCS).
Consecutive cases from 26 European colorectal units who conducted RCS between 2014 and 2018 were included in this study. The baseline characteristics and short-term outcomes of cases performed by EARCS delegates during training were analysed and compared with cases performed by EARCS graduates and proctors.
Data from 1130 RCS procedures were collected and classified into three cohort groups (323 training, 626 graduates and 181 proctors). The training cases conversion rate was 2.2% and R1 resection rate was 1.5%. The three groups were similar in terms of baseline characteristics with the exception of malignant cases and rectal resections performed. With the exception of operative time, blood loss and hospital stay (training vs. graduate vs. proctor operative time 302, 265, 255min, p < 0.001; blood loss 50, 50, 30ml, p < 0.001; hospital stay 7, 6, 6days, p = 0.003), all remaining short-term outcomes (conversion, 30-day reoperation, 30-day readmission, 30-day mortality, clinical anastomotic leak, complications, R1 resection and lymph node yield) were comparable between the three groups.
Colorectal surgeons learning how to perform RCS under the EARCS-structured training pathway can safely achieve short-term clinical outcomes comparable to their trainers and overcome the learning process in a way that minimises patient harm.
Colorectal surgeons learning how to perform RCS under the EARCS-structured training pathway can safely achieve short-term clinical outcomes comparable to their trainers and overcome the learning process in a way that minimises patient harm.
In order to efficiently perform laparoscopic microwave ablation of liver tumours precise positioning of the ablation probe is mandatory. This study evaluates the precision and ablation accuracy using the innovative laparoscopic stereotactic navigation system CAS-One-SPOT in comparison to 2d ultrasound guided laparoscopic ablation procedures.
In a pig liver ablation model four surgeons, experienced (n = 2) and inexperienced (n = 2) in laparoscopic ablation procedures, were randomized for 2d ultrasound guided laparoscopic or stereotactic navigated laparoscopic ablation procedures. Each surgeon performed a total of 20 ablations. Total attempts of needle placements, time from tumor localization till beginning of ablation and ablation accuracy were analyzed.
The use of the laparoscopic stereotactic navigation system led to a significant reduction in total attempts of needle placement. The experienced group of surgeons reduced the mean number of attempts from 2.75 ± 2.291 in the 2d ultrasound guided ablation es and experienced surgeons without impairing the accuracy of the ablation procedure.The COVID-19 pandemic is a global crisis emanating both from a virus (SARS-CoV-2) and from the drastic actions to contain it. Here, we reflect on the immediate responses of most world powers amid the pandemic chaos totalitarian surveillance and nationalist isolation. Drawing on published literature, we consider measures such as wildlife-use bans, lockdowns and travel restrictions, along with their reverberations for people, economies and the planet. Our synthesis highlights significant shortfalls of applying command-and-control tactics in emergencies. For one, heavy-handed bans risk enormous unintended consequences and tend to fail if they lack legitimacy or clash with people's values. Furthermore, reactive and myopic strategies typically view the pandemic as a stand-alone crisis, rather than unravelling the complex interplay of nature-society interactions through which zoonotic diseases originate. A return to adaptive management approaches that recognise root causes and foster socio-ecological resilience will be essential to improve human and planetary health and mitigate future pandemics.The thawing and subsequent decomposition of large stocks of soil organic carbon (SOC) currently stored in the northern circumpolar permafrost region are projected to result in a 'positive' feedback on global warming. The magnitude of this feedback can only be assessed with improved knowledge about the total size and geographic distribution of the permafrost SOC pool. This study investigates SOC storage in an under-sampled mountain permafrost area in the Russian High Altai. SOC stocks from 39 soil pits are upscaled using a GIS-based land cover classification. We found that the top 100 cm of soils in Aktru Valley and the adjacent Kuray Basin only holds on average 2.6 ± 0.6 kg C m-2 (95% confidence interval), of which only c. 1% is stored in permafrost. Global warming will result in an upward shift of alpine life zones, with new plant cover and soil development at higher elevations. As a result, this type of mountain permafrost area might act as a net C sink in the future, representing a 'negative' feedback on global warming.
e, and a size distribution ranging from a few micrometers to submicrometers. Eu-VSOP and Gd have distinct spatial distributions in atherosclerotic plaques. While Eu-VSOP distribution is more cell-associated and might be used to monitor atherosclerotic plaque progression, Gd distribution indicates arterial calcification and might help in characterizing plaque vulnerability. Eu-VSOP and Gd have distinct spatial distributions in atherosclerotic plaques. While Eu-VSOP distribution is more cell-associated and might be used to monitor atherosclerotic plaque progression, Gd distribution indicates arterial calcification and might help in characterizing plaque vulnerability. Identifying predictors of positive surgical margins (PSM) and biochemical recurrence (BCR) after radical prostatectomy (RP) may assist clinicians in formulating prognosis. Aim of the study was to report the midterm oncologic outcomes, to identify the risk factors for PSM and BCR and assess the impact of the PSM on BCR-free survival following robot-assisted laparoscopic radical prostatectomy (RALP). From 2005 to 2010, 1679 consecutive patients underwent transperitoneal RALP. Data was retrospectively collected by an independent statistical company and analyzed in 2014. Median postoperative follow-up was 33.5 mo. BCR was defined as any detectable serum prostate-specific antigen (PSA) ≥ 0.2ng/mL in two consecutive measurements. https://www.selleckchem.com/products/cb-839.html BCR-free survival was estimated using the Kaplan-Meier method. Univariate and multivariate analysis were applied to identify risk factors for PSM and BCR. In pN0/pNx cancers, pathologic stage was pT2 in 1186 patients (71.8%), pT3 in 455 patients (27.6%), and pT4 in 11 patients (0.6%)ctor for high-quality oncologic outcomes. Despite there being a considerable amount of published studies on robotic colorectal surgery (RCS) over the last few years, there is a lack of evidence regarding RCS training pathways. This study examines the short-term clinical outcomes of an international RCS training programme (the European Academy of Robotic Colorectal Surgery-EARCS). Consecutive cases from 26 European colorectal units who conducted RCS between 2014 and 2018 were included in this study. The baseline characteristics and short-term outcomes of cases performed by EARCS delegates during training were analysed and compared with cases performed by EARCS graduates and proctors. Data from 1130 RCS procedures were collected and classified into three cohort groups (323 training, 626 graduates and 181 proctors). The training cases conversion rate was 2.2% and R1 resection rate was 1.5%. The three groups were similar in terms of baseline characteristics with the exception of malignant cases and rectal resections performed. With the exception of operative time, blood loss and hospital stay (training vs. graduate vs. proctor operative time 302, 265, 255min, p < 0.001; blood loss 50, 50, 30ml, p < 0.001; hospital stay 7, 6, 6days, p = 0.003), all remaining short-term outcomes (conversion, 30-day reoperation, 30-day readmission, 30-day mortality, clinical anastomotic leak, complications, R1 resection and lymph node yield) were comparable between the three groups. Colorectal surgeons learning how to perform RCS under the EARCS-structured training pathway can safely achieve short-term clinical outcomes comparable to their trainers and overcome the learning process in a way that minimises patient harm. Colorectal surgeons learning how to perform RCS under the EARCS-structured training pathway can safely achieve short-term clinical outcomes comparable to their trainers and overcome the learning process in a way that minimises patient harm. In order to efficiently perform laparoscopic microwave ablation of liver tumours precise positioning of the ablation probe is mandatory. This study evaluates the precision and ablation accuracy using the innovative laparoscopic stereotactic navigation system CAS-One-SPOT in comparison to 2d ultrasound guided laparoscopic ablation procedures. In a pig liver ablation model four surgeons, experienced (n = 2) and inexperienced (n = 2) in laparoscopic ablation procedures, were randomized for 2d ultrasound guided laparoscopic or stereotactic navigated laparoscopic ablation procedures. Each surgeon performed a total of 20 ablations. Total attempts of needle placements, time from tumor localization till beginning of ablation and ablation accuracy were analyzed. The use of the laparoscopic stereotactic navigation system led to a significant reduction in total attempts of needle placement. The experienced group of surgeons reduced the mean number of attempts from 2.75 ± 2.291 in the 2d ultrasound guided ablation es and experienced surgeons without impairing the accuracy of the ablation procedure.The COVID-19 pandemic is a global crisis emanating both from a virus (SARS-CoV-2) and from the drastic actions to contain it. Here, we reflect on the immediate responses of most world powers amid the pandemic chaos totalitarian surveillance and nationalist isolation. Drawing on published literature, we consider measures such as wildlife-use bans, lockdowns and travel restrictions, along with their reverberations for people, economies and the planet. Our synthesis highlights significant shortfalls of applying command-and-control tactics in emergencies. For one, heavy-handed bans risk enormous unintended consequences and tend to fail if they lack legitimacy or clash with people's values. Furthermore, reactive and myopic strategies typically view the pandemic as a stand-alone crisis, rather than unravelling the complex interplay of nature-society interactions through which zoonotic diseases originate. A return to adaptive management approaches that recognise root causes and foster socio-ecological resilience will be essential to improve human and planetary health and mitigate future pandemics.The thawing and subsequent decomposition of large stocks of soil organic carbon (SOC) currently stored in the northern circumpolar permafrost region are projected to result in a 'positive' feedback on global warming. The magnitude of this feedback can only be assessed with improved knowledge about the total size and geographic distribution of the permafrost SOC pool. This study investigates SOC storage in an under-sampled mountain permafrost area in the Russian High Altai. SOC stocks from 39 soil pits are upscaled using a GIS-based land cover classification. We found that the top 100 cm of soils in Aktru Valley and the adjacent Kuray Basin only holds on average 2.6 ± 0.6 kg C m-2 (95% confidence interval), of which only c. 1% is stored in permafrost. Global warming will result in an upward shift of alpine life zones, with new plant cover and soil development at higher elevations. As a result, this type of mountain permafrost area might act as a net C sink in the future, representing a 'negative' feedback on global warming.0 Commentarii 0 Distribuiri 68 Views 0 previzualizareVă rugăm să vă autentificați pentru a vă dori, partaja și comenta! -
ess then 0.05) were all significantly higher after CP. On long-term follow-up, DP patients were more likely to have postoperative exocrine (RR 0.56; 95% CI 0.37 to 0.84; P less then 0.05) and endocrine (RR 0.27; 95% CI 0.18 to 0.40; P less then 0.001) insufficiency. There was no statistically significant difference in transfusion requirement, postoperative mortality, reoperation, and tumor recurrence. Conclusion CP is associated with significantly higher morbidity and clinically relevant pancreatic fistula. CP should only be reserved for selected patients who require postoperative pancreatic function preservation. Copyright © 2020 Parbatraj Regmi et al.Background Patients with brain metastases (BM) from renal cell carcinoma (RCC) were considered to experience a poor prognosis. However, there is little knowledge on the risk factors for BM from RCC at diagnosis. This study was aimed at exploring the risk factors for patients with BM from RCC and the interaction among these risk factors. Methods A total of 38759 cases of RCC were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Risk factors for BM from RCC were evaluated by univariate and multivariate logistic regression analyses. Interaction effect between age and tumor size was tested. Results There was a significant difference in univariate analysis, including T stage, tumor size, grades III and IV, lymph node metastasis, bone metastasis, liver metastasis, lung metastasis, and surgery. There was a significant difference in multivariate analysis, including age, T stage, tumor size less then 10 cm, grade IV, lymph node metastasis, bone metastasis, lung metastasis, and surgery. Patients older than 70 had 0.653-fold lower risk of developing BM compared with those younger than 70. Patients with tumor size ≥ 4 cm and less then 10 cm had higher risk of developing BM compared with those less then 4 cm. The larger the tumor size, the higher the incidence of BM from RCC in those whose tumor size was less than 10 cm. An interaction test between the tumor size and age on brain metastasis was statistically significant in the crude analysis (P = 0.0114) and model II analysis (P = 0.0114) and model II analysis (P = 0.0114) and model II analysis (. Conclusion Both tumor size and age were independent risk factors for brain metastases in patients with RCC. The impact of age on the risk of developing BM from RCC was limited to patients with tumor size ≥ 7 cm. Patients with a larger tumor size and younger age might have the higher risk of developing BM at diagnosis of RCC. Copyright © 2020 Zhi-Bin Ke et al.The MnSOD Ala16Val single nucleotide polymorphism (SNP) has been associated with different diseases. However, there are scarcely studies relating this SNP in epilepsy, a neurologic disease that involves some interacting pathways, such as apoptotic and inflammatory factors. In this sense, we decided to investigate the relationship of MnSOD Ala16Val SNP with apoptotic markers in epilepsy and its relation with inflammatory pathway and seizure type. Ninety subjects were evaluated (47 epilepsies; 43 controls) by questionnaires and laboratorial exams. We observed a higher percentage of VV genotype in the epilepsy group when compared to the control group. IL-1β, IL-6, caspase-1, and caspase-3 levels were increased in the epilepsy group (VV genotype). Furthermore, an important correlation between IL-1β vs. caspase-1 and IL-6 vs. caspase-3 was observed in the epilepsy group (VV genotype). The epilepsy group which presented generalized seizures also demonstrated a positive correlation between IL-1β vs. CASP1 and IL-6 vs. CASP3. Thus, it is a plausible propose that epilepsy patients with VV genotype and generalized seizures present a worse inflammatory and apoptotic status. Our findings suggest that the knowledge of MnSOD Ala16Val polymorphism existence is important to evaluate molecular mechanisms associated to seizure and improve the treatment of these patients. Copyright © 2020 Aline Kegler et al.Background There is no evidence to suggest the predictive power of neutrophil percentage-to-albumin ratio (NPAR) in patients with acute kidney injury (AKI). We hypothesized that NPAR would correlate with all-cause mortality in critically ill patients with AKI. Methods From the MIMIC-III V1.4 database, we extracted demographics, vital signs, comorbidities, laboratory tests, and other clinical data. https://www.selleckchem.com/products/tpen.html The clinical endpoints were 30-, 90- and 365-day all-cause mortality in critically ill patients with AKI. Cox proportional hazards models were used to evaluate the prognostic values of NPAR, and subgroup analyses were performed to measure mortality across various subgroups. Results A total of 7,481 eligible subjects were enrolled. In multivariate analysis, after adjustments for age, ethnicity, gender, and other confounding factors, higher NPARs were associated with an increased risk of 30-, 90- and 365-day all-cause mortality in critically ill patients with AKI (tertile 3 versus tertile 1 adjusted HR, 95% CI 1.48, 1.30-1.69; 1.47, 1.31-1.66; 1.46, 1.32-1.62, respectively; P trend less then 0.01). A similar trend was observed in the NPAR group division by quintiles. Subgroup analysis revealed no significant interactions in most strata. Conclusions Increased NPAR correlates with increased risk of all-cause mortality in critically ill patients with AKI. Copyright © 2020 Benji Wang et al.To evaluate the necessity and safety of preoperative oral carbohydrates in enhanced recovery after surgery (ERAS) protocols for diabetes mellitus patients. We searched PubMed, EMBASE, the Cochrane Library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, and WANFANG databases for articles published through September 2018. We used the Cochrane risk-of-bias tool to assess the methodological quality of included studies. Literature screening, data extraction, and quality evaluation were performed independently by two investigators. Of the 6328 retrieved articles, five eligible randomized controlled trials were included. Two were from China and three were from Germany, Sweden, and Canada. Preoperative oral carbohydrates may facilitate control of preoperative blood glucose, improve postoperative insulin resistance in diabetes patients, and decrease the occurrence of adverse reactions. However, the overall quality of the included studies was low. The available evidence shows that preoperative oral carbohydrates are probably beneficial for patients with diabetes mellitus.
ess then 0.05) were all significantly higher after CP. On long-term follow-up, DP patients were more likely to have postoperative exocrine (RR 0.56; 95% CI 0.37 to 0.84; P less then 0.05) and endocrine (RR 0.27; 95% CI 0.18 to 0.40; P less then 0.001) insufficiency. There was no statistically significant difference in transfusion requirement, postoperative mortality, reoperation, and tumor recurrence. Conclusion CP is associated with significantly higher morbidity and clinically relevant pancreatic fistula. CP should only be reserved for selected patients who require postoperative pancreatic function preservation. Copyright © 2020 Parbatraj Regmi et al.Background Patients with brain metastases (BM) from renal cell carcinoma (RCC) were considered to experience a poor prognosis. However, there is little knowledge on the risk factors for BM from RCC at diagnosis. This study was aimed at exploring the risk factors for patients with BM from RCC and the interaction among these risk factors. Methods A total of 38759 cases of RCC were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Risk factors for BM from RCC were evaluated by univariate and multivariate logistic regression analyses. Interaction effect between age and tumor size was tested. Results There was a significant difference in univariate analysis, including T stage, tumor size, grades III and IV, lymph node metastasis, bone metastasis, liver metastasis, lung metastasis, and surgery. There was a significant difference in multivariate analysis, including age, T stage, tumor size less then 10 cm, grade IV, lymph node metastasis, bone metastasis, lung metastasis, and surgery. Patients older than 70 had 0.653-fold lower risk of developing BM compared with those younger than 70. Patients with tumor size ≥ 4 cm and less then 10 cm had higher risk of developing BM compared with those less then 4 cm. The larger the tumor size, the higher the incidence of BM from RCC in those whose tumor size was less than 10 cm. An interaction test between the tumor size and age on brain metastasis was statistically significant in the crude analysis (P = 0.0114) and model II analysis (P = 0.0114) and model II analysis (P = 0.0114) and model II analysis (. Conclusion Both tumor size and age were independent risk factors for brain metastases in patients with RCC. The impact of age on the risk of developing BM from RCC was limited to patients with tumor size ≥ 7 cm. Patients with a larger tumor size and younger age might have the higher risk of developing BM at diagnosis of RCC. Copyright © 2020 Zhi-Bin Ke et al.The MnSOD Ala16Val single nucleotide polymorphism (SNP) has been associated with different diseases. However, there are scarcely studies relating this SNP in epilepsy, a neurologic disease that involves some interacting pathways, such as apoptotic and inflammatory factors. In this sense, we decided to investigate the relationship of MnSOD Ala16Val SNP with apoptotic markers in epilepsy and its relation with inflammatory pathway and seizure type. Ninety subjects were evaluated (47 epilepsies; 43 controls) by questionnaires and laboratorial exams. We observed a higher percentage of VV genotype in the epilepsy group when compared to the control group. IL-1β, IL-6, caspase-1, and caspase-3 levels were increased in the epilepsy group (VV genotype). Furthermore, an important correlation between IL-1β vs. caspase-1 and IL-6 vs. caspase-3 was observed in the epilepsy group (VV genotype). The epilepsy group which presented generalized seizures also demonstrated a positive correlation between IL-1β vs. CASP1 and IL-6 vs. CASP3. Thus, it is a plausible propose that epilepsy patients with VV genotype and generalized seizures present a worse inflammatory and apoptotic status. Our findings suggest that the knowledge of MnSOD Ala16Val polymorphism existence is important to evaluate molecular mechanisms associated to seizure and improve the treatment of these patients. Copyright © 2020 Aline Kegler et al.Background There is no evidence to suggest the predictive power of neutrophil percentage-to-albumin ratio (NPAR) in patients with acute kidney injury (AKI). We hypothesized that NPAR would correlate with all-cause mortality in critically ill patients with AKI. Methods From the MIMIC-III V1.4 database, we extracted demographics, vital signs, comorbidities, laboratory tests, and other clinical data. https://www.selleckchem.com/products/tpen.html The clinical endpoints were 30-, 90- and 365-day all-cause mortality in critically ill patients with AKI. Cox proportional hazards models were used to evaluate the prognostic values of NPAR, and subgroup analyses were performed to measure mortality across various subgroups. Results A total of 7,481 eligible subjects were enrolled. In multivariate analysis, after adjustments for age, ethnicity, gender, and other confounding factors, higher NPARs were associated with an increased risk of 30-, 90- and 365-day all-cause mortality in critically ill patients with AKI (tertile 3 versus tertile 1 adjusted HR, 95% CI 1.48, 1.30-1.69; 1.47, 1.31-1.66; 1.46, 1.32-1.62, respectively; P trend less then 0.01). A similar trend was observed in the NPAR group division by quintiles. Subgroup analysis revealed no significant interactions in most strata. Conclusions Increased NPAR correlates with increased risk of all-cause mortality in critically ill patients with AKI. Copyright © 2020 Benji Wang et al.To evaluate the necessity and safety of preoperative oral carbohydrates in enhanced recovery after surgery (ERAS) protocols for diabetes mellitus patients. We searched PubMed, EMBASE, the Cochrane Library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, and WANFANG databases for articles published through September 2018. We used the Cochrane risk-of-bias tool to assess the methodological quality of included studies. Literature screening, data extraction, and quality evaluation were performed independently by two investigators. Of the 6328 retrieved articles, five eligible randomized controlled trials were included. Two were from China and three were from Germany, Sweden, and Canada. Preoperative oral carbohydrates may facilitate control of preoperative blood glucose, improve postoperative insulin resistance in diabetes patients, and decrease the occurrence of adverse reactions. However, the overall quality of the included studies was low. The available evidence shows that preoperative oral carbohydrates are probably beneficial for patients with diabetes mellitus.0 Commentarii 0 Distribuiri 79 Views 0 previzualizare -
This paper is a new step towards understanding why "quantum nonlocality" is a misleading concept. Metaphorically speaking, "quantum nonlocality" is Janus faced. One face is an apparent nonlocality of the Lüders projection and another face is **** nonlocality (a wrong conclusion that the violation of **** type inequalities implies the existence of mysterious instantaneous influences between distant physical systems). According to the Lüders projection postulate, a quantum measurement performed on one of the two distant entangled physical systems modifies their compound quantum state instantaneously. Therefore, if the quantum state is considered to be an attribute of the individual physical system and if one assumes that experimental outcomes are produced in a perfectly random way, one quickly arrives at the contradiction. It is a primary source of speculations about a spooky action at a distance. **** nonlocality as defined above was explained and rejected by several authors; thus, we concentrate in this paperr spooky predictions at a distance are simply misleading. Coming **** to **** nonlocality, we recall that in a recent paper we demonstrated, using exclusively the quantum formalism, that CHSH inequalities may be violated for some quantum states only because of the incompatibility of quantum observables and Bohr's complementarity. Finally, we explain that our criticism of quantum nonlocality is in the spirit of Hertz-Boltzmann methodology of scientific theories.Quantum uncertainty has a tremendous explanatory power. https://www.selleckchem.com/products/sw033291.html Coherent superposition, quantum equations of motion, entanglement, nonlocal correlations, dynamical nonlocality, contextuality, discord, counterfactual protocols, weak measurements, quantization itself, and even preservation of causality can be traced **** to quantum uncertainty. We revisit and extend our previous works, as well as some other works of the community, in order to account for the above claims. Special emphasis is given to the connection between uncertainty and nonlocality, two notions which evolved quite independently and may seem distinct but, in fact, are tightly related. Indeterminism, or more precisely, locally consistent indeterminism, should be understood as the enabler of most quantum phenomena (and possibly all of them).Black hole (BH) collisions produce gravitational radiation which is generally thought, in a quantum limit, to be gravitons. The stretched horizon of a black hole contains quantum information, or a form of quantum hair, which is a coalescence of black holes participating in the generation of gravitons. This may be facilitated with a Bohr-like approach to black hole (BH) quantum physics with quasi-normal mode (QNM) approach to BH quantum mechanics. Quantum gravity and quantum hair on event horizons is excited to higher energy in BH coalescence. The near horizon condition for two BHs right before collision is a deformed A d S spacetime. These excited states of BH quantum hair then relax with the production of gravitons. This is then argued to define RT entropy given by quantum hair on the horizons. These qubits of information from a BH coalescence should then appear in gravitational wave (GW) data.This paper presents integer and linear time-invariant fractional order (FO) models of a closed-loop electric individual-wheel drive implemented on an autonomous platform. Two discrete-time FO models are tested non-commensurate and commensurate. A classical model described by the second-order linear difference equation is used as the reference. According to the sum of the squared error criterion (SSE), we compare a two-parameter integer order model with four-parameter non-commensurate and three-parameter commensurate FO descriptions. The computer simulation results are compared with the measured velocity of a real autonomous platform powered by a closed-loop electric individual-wheel drive.In an energy system, it is important to identify the origin of residue formation in order to implement actions to reduce their formation or to eliminate them as well as to evaluate their impact on the production costs of the system. In the exergetic cost theory, although there are several criteria to allocate the cost formation of residues to the productive components, no unique indication on the best choice has been defined yet. In this paper, the production exergy costs are determined by allocating the residue cost formation to the irreversibilities of the productive components from which they originate. This criterion, based on the Gouy-Stodola theorem, is an extension of the criterion of entropy changes, and unlike this, it avoids the existence of a negative production cost. This criterion is applied to a combined cycle of three pressure levels, and the production exergy costs are compared with the criteria of entropy changes, distributed exergy, and entropy. The results of the proposed criterion are in agreement with the compared criteria.It has been shown that joint probability distributions of quantum systems generally do not exist, and the key to solving this concern is the compound state invented by Ohya. The Ohya compound state constructed by the Schatten decomposition (i.e., one-dimensional orthogonal projection) of the input state shows the correlation between the states of the input and output systems. In 1983, Ohya formulated the quantum mutual entropy by applying this compound state. Since this mutual entropy satisfies the fundamental inequality, one may say that it represents the amount of information correctly transmitted from the input system through the channel to the output system, and it may play an important role in discussing the efficiency of information transfer in quantum systems. Since the Ohya compound state is separable state, it is important that we must look more carefully into the entangled compound state. This paper is intended as an investigation of the construction of the entangled compound state, and the hybrid entangled compound state is introduced. The purpose of this paper is to consider the validity of the compound states constructing the quantum mutual entropy type complexity. It seems reasonable to suppose that the quantum mutual entropy type complexity defined by using the entangled compound state is not useful to discuss the efficiency of information transmission from the initial system to the final system.
This paper is a new step towards understanding why "quantum nonlocality" is a misleading concept. Metaphorically speaking, "quantum nonlocality" is Janus faced. One face is an apparent nonlocality of the Lüders projection and another face is Bell nonlocality (a wrong conclusion that the violation of Bell type inequalities implies the existence of mysterious instantaneous influences between distant physical systems). According to the Lüders projection postulate, a quantum measurement performed on one of the two distant entangled physical systems modifies their compound quantum state instantaneously. Therefore, if the quantum state is considered to be an attribute of the individual physical system and if one assumes that experimental outcomes are produced in a perfectly random way, one quickly arrives at the contradiction. It is a primary source of speculations about a spooky action at a distance. Bell nonlocality as defined above was explained and rejected by several authors; thus, we concentrate in this paperr spooky predictions at a distance are simply misleading. Coming back to Bell nonlocality, we recall that in a recent paper we demonstrated, using exclusively the quantum formalism, that CHSH inequalities may be violated for some quantum states only because of the incompatibility of quantum observables and Bohr's complementarity. Finally, we explain that our criticism of quantum nonlocality is in the spirit of Hertz-Boltzmann methodology of scientific theories.Quantum uncertainty has a tremendous explanatory power. https://www.selleckchem.com/products/sw033291.html Coherent superposition, quantum equations of motion, entanglement, nonlocal correlations, dynamical nonlocality, contextuality, discord, counterfactual protocols, weak measurements, quantization itself, and even preservation of causality can be traced back to quantum uncertainty. We revisit and extend our previous works, as well as some other works of the community, in order to account for the above claims. Special emphasis is given to the connection between uncertainty and nonlocality, two notions which evolved quite independently and may seem distinct but, in fact, are tightly related. Indeterminism, or more precisely, locally consistent indeterminism, should be understood as the enabler of most quantum phenomena (and possibly all of them).Black hole (BH) collisions produce gravitational radiation which is generally thought, in a quantum limit, to be gravitons. The stretched horizon of a black hole contains quantum information, or a form of quantum hair, which is a coalescence of black holes participating in the generation of gravitons. This may be facilitated with a Bohr-like approach to black hole (BH) quantum physics with quasi-normal mode (QNM) approach to BH quantum mechanics. Quantum gravity and quantum hair on event horizons is excited to higher energy in BH coalescence. The near horizon condition for two BHs right before collision is a deformed A d S spacetime. These excited states of BH quantum hair then relax with the production of gravitons. This is then argued to define RT entropy given by quantum hair on the horizons. These qubits of information from a BH coalescence should then appear in gravitational wave (GW) data.This paper presents integer and linear time-invariant fractional order (FO) models of a closed-loop electric individual-wheel drive implemented on an autonomous platform. Two discrete-time FO models are tested non-commensurate and commensurate. A classical model described by the second-order linear difference equation is used as the reference. According to the sum of the squared error criterion (SSE), we compare a two-parameter integer order model with four-parameter non-commensurate and three-parameter commensurate FO descriptions. The computer simulation results are compared with the measured velocity of a real autonomous platform powered by a closed-loop electric individual-wheel drive.In an energy system, it is important to identify the origin of residue formation in order to implement actions to reduce their formation or to eliminate them as well as to evaluate their impact on the production costs of the system. In the exergetic cost theory, although there are several criteria to allocate the cost formation of residues to the productive components, no unique indication on the best choice has been defined yet. In this paper, the production exergy costs are determined by allocating the residue cost formation to the irreversibilities of the productive components from which they originate. This criterion, based on the Gouy-Stodola theorem, is an extension of the criterion of entropy changes, and unlike this, it avoids the existence of a negative production cost. This criterion is applied to a combined cycle of three pressure levels, and the production exergy costs are compared with the criteria of entropy changes, distributed exergy, and entropy. The results of the proposed criterion are in agreement with the compared criteria.It has been shown that joint probability distributions of quantum systems generally do not exist, and the key to solving this concern is the compound state invented by Ohya. The Ohya compound state constructed by the Schatten decomposition (i.e., one-dimensional orthogonal projection) of the input state shows the correlation between the states of the input and output systems. In 1983, Ohya formulated the quantum mutual entropy by applying this compound state. Since this mutual entropy satisfies the fundamental inequality, one may say that it represents the amount of information correctly transmitted from the input system through the channel to the output system, and it may play an important role in discussing the efficiency of information transfer in quantum systems. Since the Ohya compound state is separable state, it is important that we must look more carefully into the entangled compound state. This paper is intended as an investigation of the construction of the entangled compound state, and the hybrid entangled compound state is introduced. The purpose of this paper is to consider the validity of the compound states constructing the quantum mutual entropy type complexity. It seems reasonable to suppose that the quantum mutual entropy type complexity defined by using the entangled compound state is not useful to discuss the efficiency of information transmission from the initial system to the final system.0 Commentarii 0 Distribuiri 75 Views 0 previzualizare -
Advances made in fabrication of patterned surfaces with well-defined dimensions of topographic features and their lateral dissemination drive the progress in interpretation of liquid spreading, adhesion, and retreat on engineered solid surfaces. Despite extensive studies on liquid droplet spreading and adhesion on textured surfaces in recent years, conformation of the three-phase contact line and its effect on macroscopic contact angle and droplet adhesion remain the focus of intensive debate. Here, we investigate the effect of surface topography on the adhesion force of Cassie-Baxter-state droplets on concentric ring-textured hydrophobic surfaces having rings with lateral dimensions of 5, 10, and 45 μm and separated by 5, 6, and 7 μm trenches, respectively, with fixed depth of 15 μm. Unlike mostly tested surfaces textured with straight ridges, pores, and pillars, where the droplet base contact line is anisotropic and its conformation varies along the apparent boundary, concentric rings are symmetrical and reinforce the microscopic contact line to align to a circular one that reflects the shape of the pattern. In this study, adhesion forces were calculated based on surface tension and Laplace pressure forces and were compared with the experimental forces for both water and ethylene glycol droplets having a varying contact diameter on the concentric ring-pattern at the point of maximum adhesion force. Results show that the microscopic contact line of the liquid retains its circular shape controlled by circular rings of the pattern, irrespectively of the droplet base diameter larger than 0.8 mm, and there is a good agreement between the experimental and calculated adhesion forces.A general and practical method for decarboxylative hydroxylation of carboxylic acids was developed through visible light-induced photocatalysis using molecular oxygen as the green oxidant. The addition of NaBH4 to in situ reduce the unstable peroxyl radical intermediate **** broadened the substrate scope. Different sp3 carbon-bearing carboxylic acids were successfully employed as substrates, including phenylacetic acid-type substrates, as well as aliphatic carboxylic acids. This transformation worked smoothly on primary, secondary, and tertiary carboxylic acids.We have investigated the chemical bath deposition (CBD) of CuS using thioacetamide on functionalized self-assembled monolayers (SAMs) using scanning electron and optical microscopies, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry. For all SAMs studied, the amount of CuS deposited is strongly dependent on the bath pH and can be attributed to the interaction of the SAM terminal groups with the chalcogenide ions present in solution. For -CH3-terminated SAMs, there is a steady increase in the amount of CuS deposited with an increase in the bath pH because there is an increase in the concentration of chalcogenide ion. However, for -OH- and -COOH-terminated SAMs, we observe that the maximum amount of CuS is deposited at pH 10. We attribute this behavior to a competition between the repulsion of the chalcogenide ions by the negatively charged SAM terminal groups and an increase in the chalcogenide ion concentration with an increase in the bath pH. Using the interaction of the chalcogenide ions with the different SAM terminal functional groups, we demonstrate that CuS can be selectively deposited on the -CH3-terminated areas of patterned -OH/-CH3- and -COOH/-CH3-terminated SAMs.Algae products are attracting growing interest due to their pleasant taste and their high contents in protein, essential amino acids, vitamins, and minerals. Specifically, spirulina products are widely promoted for their high vitamin B12 content. https://www.selleckchem.com/products/3-aminobenzamide.html So far, knowledge regarding the contamination with cyanotoxins, heavy metals, pesticides, or polycyclic aromatic hydrocarbons (PAHs) is scarce, although some studies reported high contaminant levels in spirulina products. The regular intake of spirulina, and very likely other algae products as well, as a dietary supplement in the gram range demands a closer monitoring of potentially harmful constituents.Antioxidant metabolites contribute to alleviating oxidative stress caused by reactive oxygen species (ROS) in microorganisms. We utilized oxidative stressors such as hydrogen peroxide supplementation to increase the yield of the bioactive secondary metabolite antioxidant antrodin C in submerged fermentations of the medicinal mushroom Antrodia cinnamomea. Changes in the superoxide dismutase and catalase activities of the cells indicate that ROS are critical to promote antrodin C biosynthesis, while the ROS production inhibitor diphenyleneiodonium cancels the productivity-enhancing effects of H2O2. Transcriptomic analysis suggests that key enzymes in the mitochondrial electron transport chain are repressed during oxidative stress, leading to ROS accumulation and triggering the biosynthesis of antioxidants such as antrodin C. Accordingly, rotenone, an inhibitor of the electron transport chain complex I, mimics the antrodin C productivity-enhancing effects of H2O2. Delineating the steps connecting oxidative stress with increased antrodin C biosynthesis will facilitate the fine-tuning of strategies for rational fermentation process improvement.Phenoxyalkanoic acid (PAA) herbicides are mainly metabolized by microorganisms in soils, but the degraders that perform well under alkaline environments are rarely considered. Herein, we report Cupriavidus oxalaticus strain X32, which showed encouraging PAA-degradation abilities, PAA tolerance, and alkali tolerance. In liquid media, without the addition of exogenous carbon sources, X32 could completely remove 500 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) or 4-chloro-2-methylphenoxyacetic acid within 3 days, faster than that with the model degrader Cupriavidus necator JMP134. Particularly, X32 still functioned at pH 10.5. Of note, with X32 inoculation, we observed 2,4-D degradation in soils and diminished phytotoxicity to maize (Zea mays). Furthermore, potential mechanisms underlying PAA biodegradation and alkali tolerance were then analyzed by whole-genome sequencing. Three modules of tfd gene clusters involved in 2,4-D catabolism and genes encoding monovalent cation/proton antiporters involved in alkali tolerance were putatively identified.
Advances made in fabrication of patterned surfaces with well-defined dimensions of topographic features and their lateral dissemination drive the progress in interpretation of liquid spreading, adhesion, and retreat on engineered solid surfaces. Despite extensive studies on liquid droplet spreading and adhesion on textured surfaces in recent years, conformation of the three-phase contact line and its effect on macroscopic contact angle and droplet adhesion remain the focus of intensive debate. Here, we investigate the effect of surface topography on the adhesion force of Cassie-Baxter-state droplets on concentric ring-textured hydrophobic surfaces having rings with lateral dimensions of 5, 10, and 45 μm and separated by 5, 6, and 7 μm trenches, respectively, with fixed depth of 15 μm. Unlike mostly tested surfaces textured with straight ridges, pores, and pillars, where the droplet base contact line is anisotropic and its conformation varies along the apparent boundary, concentric rings are symmetrical and reinforce the microscopic contact line to align to a circular one that reflects the shape of the pattern. In this study, adhesion forces were calculated based on surface tension and Laplace pressure forces and were compared with the experimental forces for both water and ethylene glycol droplets having a varying contact diameter on the concentric ring-pattern at the point of maximum adhesion force. Results show that the microscopic contact line of the liquid retains its circular shape controlled by circular rings of the pattern, irrespectively of the droplet base diameter larger than 0.8 mm, and there is a good agreement between the experimental and calculated adhesion forces.A general and practical method for decarboxylative hydroxylation of carboxylic acids was developed through visible light-induced photocatalysis using molecular oxygen as the green oxidant. The addition of NaBH4 to in situ reduce the unstable peroxyl radical intermediate much broadened the substrate scope. Different sp3 carbon-bearing carboxylic acids were successfully employed as substrates, including phenylacetic acid-type substrates, as well as aliphatic carboxylic acids. This transformation worked smoothly on primary, secondary, and tertiary carboxylic acids.We have investigated the chemical bath deposition (CBD) of CuS using thioacetamide on functionalized self-assembled monolayers (SAMs) using scanning electron and optical microscopies, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry. For all SAMs studied, the amount of CuS deposited is strongly dependent on the bath pH and can be attributed to the interaction of the SAM terminal groups with the chalcogenide ions present in solution. For -CH3-terminated SAMs, there is a steady increase in the amount of CuS deposited with an increase in the bath pH because there is an increase in the concentration of chalcogenide ion. However, for -OH- and -COOH-terminated SAMs, we observe that the maximum amount of CuS is deposited at pH 10. We attribute this behavior to a competition between the repulsion of the chalcogenide ions by the negatively charged SAM terminal groups and an increase in the chalcogenide ion concentration with an increase in the bath pH. Using the interaction of the chalcogenide ions with the different SAM terminal functional groups, we demonstrate that CuS can be selectively deposited on the -CH3-terminated areas of patterned -OH/-CH3- and -COOH/-CH3-terminated SAMs.Algae products are attracting growing interest due to their pleasant taste and their high contents in protein, essential amino acids, vitamins, and minerals. Specifically, spirulina products are widely promoted for their high vitamin B12 content. https://www.selleckchem.com/products/3-aminobenzamide.html So far, knowledge regarding the contamination with cyanotoxins, heavy metals, pesticides, or polycyclic aromatic hydrocarbons (PAHs) is scarce, although some studies reported high contaminant levels in spirulina products. The regular intake of spirulina, and very likely other algae products as well, as a dietary supplement in the gram range demands a closer monitoring of potentially harmful constituents.Antioxidant metabolites contribute to alleviating oxidative stress caused by reactive oxygen species (ROS) in microorganisms. We utilized oxidative stressors such as hydrogen peroxide supplementation to increase the yield of the bioactive secondary metabolite antioxidant antrodin C in submerged fermentations of the medicinal mushroom Antrodia cinnamomea. Changes in the superoxide dismutase and catalase activities of the cells indicate that ROS are critical to promote antrodin C biosynthesis, while the ROS production inhibitor diphenyleneiodonium cancels the productivity-enhancing effects of H2O2. Transcriptomic analysis suggests that key enzymes in the mitochondrial electron transport chain are repressed during oxidative stress, leading to ROS accumulation and triggering the biosynthesis of antioxidants such as antrodin C. Accordingly, rotenone, an inhibitor of the electron transport chain complex I, mimics the antrodin C productivity-enhancing effects of H2O2. Delineating the steps connecting oxidative stress with increased antrodin C biosynthesis will facilitate the fine-tuning of strategies for rational fermentation process improvement.Phenoxyalkanoic acid (PAA) herbicides are mainly metabolized by microorganisms in soils, but the degraders that perform well under alkaline environments are rarely considered. Herein, we report Cupriavidus oxalaticus strain X32, which showed encouraging PAA-degradation abilities, PAA tolerance, and alkali tolerance. In liquid media, without the addition of exogenous carbon sources, X32 could completely remove 500 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) or 4-chloro-2-methylphenoxyacetic acid within 3 days, faster than that with the model degrader Cupriavidus necator JMP134. Particularly, X32 still functioned at pH 10.5. Of note, with X32 inoculation, we observed 2,4-D degradation in soils and diminished phytotoxicity to maize (Zea mays). Furthermore, potential mechanisms underlying PAA biodegradation and alkali tolerance were then analyzed by whole-genome sequencing. Three modules of tfd gene clusters involved in 2,4-D catabolism and genes encoding monovalent cation/proton antiporters involved in alkali tolerance were putatively identified.0 Commentarii 0 Distribuiri 72 Views 0 previzualizare -
In addition, the prepared BSMA particles have well-developed mesoporous characteristics with relatively large surface areas, which are beneficial for adsorption of gas molecules. In an ammonia adsorption experiment, the BSMA-1.5 sample, which has the smallest particle diameter among the bead samples, was the best in terms of adsorption capacity. In this manuscript, we systemically discuss the relationship between the characteristics of BSMA samples and their adsorption of ammonia.Biological crop protection is recommended to be applied alternately or together with chemical one, to protect human health from the excessive use of toxic pesticides. https://www.selleckchem.com/PI3K.html Presence of microorganisms can influence the concentration of chemical pollutants in soil. The aim of this study is to estimate the influence of a commercial biological fungicide containing Trichoderma harzianum Rifai T-22 on dissipation kinetics and degradation of five herbicides belonging to different chemical classes clomazone, fluazifop-P-butyl, metribuzin, pendimethalin, and propyzamide, in two types of soil. Results of the study revealed that T. harzianum T-22 influences pesticide degradation and dissipation kinetics of the non-persistent herbicides clomazone, fluazifop-P-butyl, and metribuzin. In soil with a higher content of nitrogen, phosphorus, and organic matter, degradation increased by up to 24.2%, 24.8%, and 23.5% for clomazone, fluazifop-P-butyl, and metribuzin, respectively. In soil with lower organic content, degradation was on a low level, of 16.1%, 17.7%, and 16.3% for clomazone, fluazifop-P-butyl, and metribuzin, respectively. In our study, the addition of the biological preparation shortened herbicide dissipation half-lives, from 0.3 days (2.9%) for fluazifop-P-butyl, to 18.4 days (25.1%) for clomazone. During the degradation study, no significant differences were noticed for pendimethalin, belonging to persistent substances. Biological protection of crops can modify pesticide concentrations and dissipation rates. On one hand, this may result in the reduced effectiveness of herbicide treatments, while on the other, it can become a tool for achieving cleaner environment.The morphology of thin film composite (TFC) membranes used in reverse osmosis (RO) and nanofiltration (NF) water treatment was explored with small-angle neutron scattering (SANS) and positron-annihilation lifetime spectroscopy (PALS). The combination of both methods allowed the characterization of the bulk porous structure from a few Å to µm in radius. PALS shows pores of 4.5 Å average radius in a surface layer of about 4 m thickness, which become 40% smaller at the free surface of the membranes. This observation may correlate with the glass state of the involved polymer. Pores of similar size appear in SANS as closely packed pores of 6 Å radius distributed with an average distance of 30 Å. The main effort of SANS was the characterization of the morphology of the porous polysulfone support layer as well as the fibers of the nonwoven fabric layer. Contrast variation using the media H2O/D2O and supercritical CO2 and CD4 identified the polymers of the support layers as well as internal heterogeneities.Infections caused by bacteria resistant to antibiotics are an increasing problem. Multivalent antibiotics could be a solution. In the present study, a covalent conjugate between Ciprofloxacin and a G0-PAMAM dendrimer has been synthesized and tested against clinically relevant Gram-positive and Gram-negative bacteria. The conjugate has antimicrobial activity and there is a positive dendritic effect compared to Ciprofloxacin itself.Respiratory tract infections are a global health problem. The main causative agents of these infections are influenza A virus (IAV), Staphylococcus aureus (S. aureus), and Streptococcus pneumoniae (S. pneumoniae). Major research focuses on genetics and immune responses in these infections. Eicosanoids and other oxylipins are host-derived lipid mediators that play an important role in the activation and resolution of inflammation. In this study, we assess, for the first time, the different intracellular profiles of these bioactive lipid mediators during S. aureus LUG2012, S. pneumoniae TIGR4, IAV, and corresponding viral and bacterial co-infections of 16HBE cells. We observed a multitude of altered lipid mediators. Changes in the amount of 5-hydroxyeicosatetraenoic acid (5-HETE) were prominent for all bacterial infections. The infection with S. pneumoniae showed the strongest impact on bioactive lipid production and led to alterations in the amount of PPARγ ligands and precursors of pro-resolving lipid mediators.Background and objective Magnetic resonance imaging (MRI) causes severe anxiety in some patients. Anxiety during MRI leads to prolongation of the procedure and deterioration of image quality, resulting in loss of labor and cost increase. The aim of this study was to investigate the effect of written and visual information on state anxiety in patients undergoing MRI. Material and Methods A cross-sectional prospective study was conducted with 294 participants. The study was carried out between January 2019 and March 2019 at the Radiology Clinic of the tertiary university hospital. The participants were divided into 3 groups as group 1 (control group), group 2 (written information) and group 3 (visual information). The trait anxiety and state anxiety of the participants were measured by State-Trait Anxiety Inventory (STAI) inventory, which can measure both anxiety status. Results There was no statistically significant difference between demographic characteristics and trait anxiety scores (p = 0.20) of all three groups. The state anxiety scores of group 3 were statistically lower than the group 2 (p less then 0.001) and control group (p less then 0.001). The state anxiety scores of group 2 were statistically lower than control group (p less then 0.001). Conclusion MRI anxiety can be reduced by visual and written information. Visual information may be more effective in reducing MRI anxiety than written information.The fracture performance of concrete is size-dependent within a certain size range. A four-phase composite material numerical model of mesofracture considering a mortar matrix, coarse aggregates, an interfacial transition zone (ITZ) at the meso level and the initial defects of concrete was established. The initial defects were assumed to be distributed randomly in the ITZ of concrete. The numerical model of concrete mesofracture was established to simulate the fracture process of wedge splitting (WS) concrete specimens with widths of 200-2000 mm and three-point bending (3-p-b) concrete specimens with heights of 200-800 mm. The fracture process of concrete was simulated, and the peak load (Pmax) of concrete was predicted using the numerical model. Based on the simulating results, the influence of specimen size of WS and 3-p-b tests on the fracture parameters was analyzed. It was demonstrated that when the specimen size was large enough, the fracture toughness (KIC) value obtained by the linear elastic fracture mechanics formula was independent of the specimen size.
In addition, the prepared BSMA particles have well-developed mesoporous characteristics with relatively large surface areas, which are beneficial for adsorption of gas molecules. In an ammonia adsorption experiment, the BSMA-1.5 sample, which has the smallest particle diameter among the bead samples, was the best in terms of adsorption capacity. In this manuscript, we systemically discuss the relationship between the characteristics of BSMA samples and their adsorption of ammonia.Biological crop protection is recommended to be applied alternately or together with chemical one, to protect human health from the excessive use of toxic pesticides. https://www.selleckchem.com/PI3K.html Presence of microorganisms can influence the concentration of chemical pollutants in soil. The aim of this study is to estimate the influence of a commercial biological fungicide containing Trichoderma harzianum Rifai T-22 on dissipation kinetics and degradation of five herbicides belonging to different chemical classes clomazone, fluazifop-P-butyl, metribuzin, pendimethalin, and propyzamide, in two types of soil. Results of the study revealed that T. harzianum T-22 influences pesticide degradation and dissipation kinetics of the non-persistent herbicides clomazone, fluazifop-P-butyl, and metribuzin. In soil with a higher content of nitrogen, phosphorus, and organic matter, degradation increased by up to 24.2%, 24.8%, and 23.5% for clomazone, fluazifop-P-butyl, and metribuzin, respectively. In soil with lower organic content, degradation was on a low level, of 16.1%, 17.7%, and 16.3% for clomazone, fluazifop-P-butyl, and metribuzin, respectively. In our study, the addition of the biological preparation shortened herbicide dissipation half-lives, from 0.3 days (2.9%) for fluazifop-P-butyl, to 18.4 days (25.1%) for clomazone. During the degradation study, no significant differences were noticed for pendimethalin, belonging to persistent substances. Biological protection of crops can modify pesticide concentrations and dissipation rates. On one hand, this may result in the reduced effectiveness of herbicide treatments, while on the other, it can become a tool for achieving cleaner environment.The morphology of thin film composite (TFC) membranes used in reverse osmosis (RO) and nanofiltration (NF) water treatment was explored with small-angle neutron scattering (SANS) and positron-annihilation lifetime spectroscopy (PALS). The combination of both methods allowed the characterization of the bulk porous structure from a few Å to µm in radius. PALS shows pores of 4.5 Å average radius in a surface layer of about 4 m thickness, which become 40% smaller at the free surface of the membranes. This observation may correlate with the glass state of the involved polymer. Pores of similar size appear in SANS as closely packed pores of 6 Å radius distributed with an average distance of 30 Å. The main effort of SANS was the characterization of the morphology of the porous polysulfone support layer as well as the fibers of the nonwoven fabric layer. Contrast variation using the media H2O/D2O and supercritical CO2 and CD4 identified the polymers of the support layers as well as internal heterogeneities.Infections caused by bacteria resistant to antibiotics are an increasing problem. Multivalent antibiotics could be a solution. In the present study, a covalent conjugate between Ciprofloxacin and a G0-PAMAM dendrimer has been synthesized and tested against clinically relevant Gram-positive and Gram-negative bacteria. The conjugate has antimicrobial activity and there is a positive dendritic effect compared to Ciprofloxacin itself.Respiratory tract infections are a global health problem. The main causative agents of these infections are influenza A virus (IAV), Staphylococcus aureus (S. aureus), and Streptococcus pneumoniae (S. pneumoniae). Major research focuses on genetics and immune responses in these infections. Eicosanoids and other oxylipins are host-derived lipid mediators that play an important role in the activation and resolution of inflammation. In this study, we assess, for the first time, the different intracellular profiles of these bioactive lipid mediators during S. aureus LUG2012, S. pneumoniae TIGR4, IAV, and corresponding viral and bacterial co-infections of 16HBE cells. We observed a multitude of altered lipid mediators. Changes in the amount of 5-hydroxyeicosatetraenoic acid (5-HETE) were prominent for all bacterial infections. The infection with S. pneumoniae showed the strongest impact on bioactive lipid production and led to alterations in the amount of PPARγ ligands and precursors of pro-resolving lipid mediators.Background and objective Magnetic resonance imaging (MRI) causes severe anxiety in some patients. Anxiety during MRI leads to prolongation of the procedure and deterioration of image quality, resulting in loss of labor and cost increase. The aim of this study was to investigate the effect of written and visual information on state anxiety in patients undergoing MRI. Material and Methods A cross-sectional prospective study was conducted with 294 participants. The study was carried out between January 2019 and March 2019 at the Radiology Clinic of the tertiary university hospital. The participants were divided into 3 groups as group 1 (control group), group 2 (written information) and group 3 (visual information). The trait anxiety and state anxiety of the participants were measured by State-Trait Anxiety Inventory (STAI) inventory, which can measure both anxiety status. Results There was no statistically significant difference between demographic characteristics and trait anxiety scores (p = 0.20) of all three groups. The state anxiety scores of group 3 were statistically lower than the group 2 (p less then 0.001) and control group (p less then 0.001). The state anxiety scores of group 2 were statistically lower than control group (p less then 0.001). Conclusion MRI anxiety can be reduced by visual and written information. Visual information may be more effective in reducing MRI anxiety than written information.The fracture performance of concrete is size-dependent within a certain size range. A four-phase composite material numerical model of mesofracture considering a mortar matrix, coarse aggregates, an interfacial transition zone (ITZ) at the meso level and the initial defects of concrete was established. The initial defects were assumed to be distributed randomly in the ITZ of concrete. The numerical model of concrete mesofracture was established to simulate the fracture process of wedge splitting (WS) concrete specimens with widths of 200-2000 mm and three-point bending (3-p-b) concrete specimens with heights of 200-800 mm. The fracture process of concrete was simulated, and the peak load (Pmax) of concrete was predicted using the numerical model. Based on the simulating results, the influence of specimen size of WS and 3-p-b tests on the fracture parameters was analyzed. It was demonstrated that when the specimen size was large enough, the fracture toughness (KIC) value obtained by the linear elastic fracture mechanics formula was independent of the specimen size.0 Commentarii 0 Distribuiri 77 Views 0 previzualizare -
A detailed survey via DFT calculations assessed a number of different possibilities for selectivity-determining deprotonation of the radical cation intermediate. Computations point to a clear preference for an initially unexpected mode of internal deprotonation enacted by the amide group, which is a crucial structural feature of the radical precursor, with the assistance of the associated chiral phosphate. This unconventional stereodetermining step underpins the high enantioselectivities and regioselectivities observed. The mechanistic model was further validated by applying it to a test set of substrates possessing varied structural features.Photoresponsive ligands are powerful tool compounds for studying receptor function with spatiotemporal resolution. However, to the best of our knowledge, such a ligand is not available for the ryanodine receptor (RyR). Herein, we present a photochromic ligand (PCL) for insect RyR by decorating chlorantraniliprole (CHL) with photoswitchable azobenzene (AB). We demonstrated that one potent ligand, named ABCHL13, shows light-induced reversible trans-cis isomerization and 3.5-fold insecticidal activity decrease toward oriental armyworm (Mythimna separata) after UV-light irradiation, that is, trans-ABCH13 has higher activity than the cis-ABCH13. ABCHL13 enables optical control over intracellular Ca2+ release in dorsal unpaired median (DUM) neurons of M. separata and American cockroach (Periplaneta americana) and cardiac function of P. americana. Our results provide a first photopharmacological toolkit that is applicable to light-dependent regulation of RyR and heart beating.A simple and effective annulation of ynediones and (iso)quinoline N-oxides was developed to afford various functionalized pyrrolo[2,1-a]isoquinolines and pyrrolo[1,2-a]quinolines in moderate to excellent yields. This protocol underwent a tandem [3 + 2] cycloaddition/ring-opening/N-nucleophilic addition, which exhibited high regioselectivity, broad substrate tolerance, and atom economy under catalyst-, additive-free, and air conditions. Moreover, indolizine was also successfully prepared using pyridine N-oxide.Biological molecules interact with silica (SiO2) surfaces with binding affinities that greatly vary depending on their physical-chemical properties. However, the quantitative characterization of biological compounds adsorbed on silica surfaces, especially of compounds involved in fast, reversible interactions, has been challenging, and the driving forces are not well understood. Here, we show how carbon-13 NMR spin relaxation provides quantitative atomic-detail information about the transient molecular binding to pristine silica surfaces, represented by colloidally dispersed silica nanoparticles (SNPs). Based on the quantitative analysis of almost two dozen biological molecules, we find that the addition of N-methyl motifs systematically increases molecular binding affinities to silica in a nearly quantitatively predictable manner. Among the studied compounds are methylated nucleosides, which are common in epigenetic signaling in nucleic acids. The quantitative understanding of N-methylation may open up new ways to detect and separate methylated nucleic acids or even regulate their cellular functions.Elastomers and, in particular, polydimethylsiloxane (PDMS) are widely adopted as biocompatible mechanically compliant substrates for soft and flexible micro-nanosystems in medicine, biology, and engineering. However, several applications require such low thicknesses (e.g., less then 100 μm) that make peeling-off critical because very thin elastomers become delicate and tend to exhibit strong adhesion with carriers. Moreover, microfabrication techniques such as photolithography use solvents which swell PDMS, introducing complexity and possible contamination, thus limiting industrial scalability and preventing many biomedical applications. Here, we combine low-adhesion and rectangular carrier substrates, adhesive Kapton frames, micromilling-defined shadow masks, and adhesive-neutralizing paper frames for enabling fast, easy, green, contaminant-free, and scalable manufacturing of thin elastomer devices, with both simplified peeling and handling. https://www.selleckchem.com/ The accurate alignment between the frame and shadow masks can be further facilitated by micromilled marking lines on the **** side of the low-adhesion carrier. As a proof of concept, we show epidermal sensors on a 50 μm-thick PDMS substrate for measuring strain, the skin bioimpedance and the heart rate. The proposed approach paves the way to a straightforward, green, and scalable fabrication of contaminant-free thin devices on elastomers for a wide variety of applications.An unprecedented 1,4-cycloaddition (vs 3,6-cycloaddition) of 1,2,4,5-tetrazines is described with preformed or in situ generated aryl-conjugated enamines promoted by the solvent hydrogen bonding of hexafluoroisopropanol (HFIP) that is conducted under mild reaction conditions (0.1 M HFIP, 25 °C, 12 h). The reaction constitutes a formal [4 + 2] cycloaddition across the two nitrogen atoms (N1/N4) of the 1,2,4,5-tetrazine followed by a formal retro [4 + 2] cycloaddition loss of a nitrile and aromatization to generate a 1,2,4-triazine derivative. The factors that impact the remarkable change in the reaction mode, optimization of reaction parameters, the scope and simplification of its implementation through in situ enamine generation from aldehydes and ketones, the reaction scope for 3,6-bis(thiomethyl)-1,2,4,5-tetrazine, a survey of participating 1,2,4,5-tetrazines, and key mechanistic insights into this reaction are detailed. Given its simplicity and breath, the study establishes a novel method for the simple and efficient one-step synthesis of 1,2,4-triazines under mild conditions from readily accessible starting materials. Whereas alternative protic solvents (e.g., MeOH vs HFIP) provide products of the conventional 3,6-cycoladdition, the enhanced hydrogen bonding capability of HFIP uniquely results in promotion of the unprecedented formal 1,4-cycloaddition. As such, the studies represent an example of not just an enhancement in the rate or efficiency of a heterocyclic azadiene cycloaddition by hydrogen bonding catalysis but also the first to alter the mode (N1/N4 vs C3/C6) of cycloaddition.
A detailed survey via DFT calculations assessed a number of different possibilities for selectivity-determining deprotonation of the radical cation intermediate. Computations point to a clear preference for an initially unexpected mode of internal deprotonation enacted by the amide group, which is a crucial structural feature of the radical precursor, with the assistance of the associated chiral phosphate. This unconventional stereodetermining step underpins the high enantioselectivities and regioselectivities observed. The mechanistic model was further validated by applying it to a test set of substrates possessing varied structural features.Photoresponsive ligands are powerful tool compounds for studying receptor function with spatiotemporal resolution. However, to the best of our knowledge, such a ligand is not available for the ryanodine receptor (RyR). Herein, we present a photochromic ligand (PCL) for insect RyR by decorating chlorantraniliprole (CHL) with photoswitchable azobenzene (AB). We demonstrated that one potent ligand, named ABCHL13, shows light-induced reversible trans-cis isomerization and 3.5-fold insecticidal activity decrease toward oriental armyworm (Mythimna separata) after UV-light irradiation, that is, trans-ABCH13 has higher activity than the cis-ABCH13. ABCHL13 enables optical control over intracellular Ca2+ release in dorsal unpaired median (DUM) neurons of M. separata and American cockroach (Periplaneta americana) and cardiac function of P. americana. Our results provide a first photopharmacological toolkit that is applicable to light-dependent regulation of RyR and heart beating.A simple and effective annulation of ynediones and (iso)quinoline N-oxides was developed to afford various functionalized pyrrolo[2,1-a]isoquinolines and pyrrolo[1,2-a]quinolines in moderate to excellent yields. This protocol underwent a tandem [3 + 2] cycloaddition/ring-opening/N-nucleophilic addition, which exhibited high regioselectivity, broad substrate tolerance, and atom economy under catalyst-, additive-free, and air conditions. Moreover, indolizine was also successfully prepared using pyridine N-oxide.Biological molecules interact with silica (SiO2) surfaces with binding affinities that greatly vary depending on their physical-chemical properties. However, the quantitative characterization of biological compounds adsorbed on silica surfaces, especially of compounds involved in fast, reversible interactions, has been challenging, and the driving forces are not well understood. Here, we show how carbon-13 NMR spin relaxation provides quantitative atomic-detail information about the transient molecular binding to pristine silica surfaces, represented by colloidally dispersed silica nanoparticles (SNPs). Based on the quantitative analysis of almost two dozen biological molecules, we find that the addition of N-methyl motifs systematically increases molecular binding affinities to silica in a nearly quantitatively predictable manner. Among the studied compounds are methylated nucleosides, which are common in epigenetic signaling in nucleic acids. The quantitative understanding of N-methylation may open up new ways to detect and separate methylated nucleic acids or even regulate their cellular functions.Elastomers and, in particular, polydimethylsiloxane (PDMS) are widely adopted as biocompatible mechanically compliant substrates for soft and flexible micro-nanosystems in medicine, biology, and engineering. However, several applications require such low thicknesses (e.g., less then 100 μm) that make peeling-off critical because very thin elastomers become delicate and tend to exhibit strong adhesion with carriers. Moreover, microfabrication techniques such as photolithography use solvents which swell PDMS, introducing complexity and possible contamination, thus limiting industrial scalability and preventing many biomedical applications. Here, we combine low-adhesion and rectangular carrier substrates, adhesive Kapton frames, micromilling-defined shadow masks, and adhesive-neutralizing paper frames for enabling fast, easy, green, contaminant-free, and scalable manufacturing of thin elastomer devices, with both simplified peeling and handling. https://www.selleckchem.com/ The accurate alignment between the frame and shadow masks can be further facilitated by micromilled marking lines on the back side of the low-adhesion carrier. As a proof of concept, we show epidermal sensors on a 50 μm-thick PDMS substrate for measuring strain, the skin bioimpedance and the heart rate. The proposed approach paves the way to a straightforward, green, and scalable fabrication of contaminant-free thin devices on elastomers for a wide variety of applications.An unprecedented 1,4-cycloaddition (vs 3,6-cycloaddition) of 1,2,4,5-tetrazines is described with preformed or in situ generated aryl-conjugated enamines promoted by the solvent hydrogen bonding of hexafluoroisopropanol (HFIP) that is conducted under mild reaction conditions (0.1 M HFIP, 25 °C, 12 h). The reaction constitutes a formal [4 + 2] cycloaddition across the two nitrogen atoms (N1/N4) of the 1,2,4,5-tetrazine followed by a formal retro [4 + 2] cycloaddition loss of a nitrile and aromatization to generate a 1,2,4-triazine derivative. The factors that impact the remarkable change in the reaction mode, optimization of reaction parameters, the scope and simplification of its implementation through in situ enamine generation from aldehydes and ketones, the reaction scope for 3,6-bis(thiomethyl)-1,2,4,5-tetrazine, a survey of participating 1,2,4,5-tetrazines, and key mechanistic insights into this reaction are detailed. Given its simplicity and breath, the study establishes a novel method for the simple and efficient one-step synthesis of 1,2,4-triazines under mild conditions from readily accessible starting materials. Whereas alternative protic solvents (e.g., MeOH vs HFIP) provide products of the conventional 3,6-cycoladdition, the enhanced hydrogen bonding capability of HFIP uniquely results in promotion of the unprecedented formal 1,4-cycloaddition. As such, the studies represent an example of not just an enhancement in the rate or efficiency of a heterocyclic azadiene cycloaddition by hydrogen bonding catalysis but also the first to alter the mode (N1/N4 vs C3/C6) of cycloaddition.0 Commentarii 0 Distribuiri 74 Views 0 previzualizare -
By contrast, the birds, but not the primates tested, struggled to attend to multiple variables-where two apparatuses, two tools and two reward qualities were presented simultaneously-without extended experience. These findings indicate (1) in a similar manner to humans and orangutans, New Caledonian crows and Goffin's cockatoos can flexibly make profitable decisions in some decision-making tool-use tasks, though the birds may struggle when tasks become more complex; (2) children and orangutans may have a bias to use tools in situations where adults and other tool-making species do not.This study examined the socio-demographic factors associated with normal linear growth among pre-school children living in better-off households, using survey data from Ghana, Kenya, Nigeria, Mozambique and Democratic Republic of Congo (DRC). The primary outcome variable was child height-for-age z-scores (HAZ), categorised into HAZ≥-2SD (normal growth/not stunted) and HAZ less then -2 (stunted). Using logistic regression, we estimated adjusted odds ratios (aORs) of the factors associated with normal growth. Higher maternal weight (measured by body mass index) was associated with increased odds of normal growth in Mozambique, DRC, Kenya and Nigeria. A unit increase in maternal years of education was associated with increased odds in normal growth in DRC (aOR = 1.06, 95% CI = 1.03, 1.09), Ghana (aOR = 1.08, 95% CI = 1.04, 1.12), Mozambique (aOR = 1.08, 95% CI = 1.05, 1.11) and Nigeria (aOR = 1.07, 95% CI = 1.06, 1.08). A year increase in maternal age was positively associated with normal growth in all the five wth. In contrast, maternal parity, employment, and child sex and age are associated negatively with normal growth. Interventions to improve child growth should take into account these differential effects.BACKGROUND With data becoming a centerpiece of modern scientific discovery, data sharing by scientists is now a crucial element of scientific progress. This article aims to provide an in-depth examination of the practices and perceptions of data management, including data storage, data sharing, and data use and reuse by scientists around the world. METHODS The Usability and Assessment Working Group of DataONE, an NSF-funded environmental cyberinfrastructure project, distributed a survey to a multinational and multidisciplinary sample of scientific researchers in a two-waves approach in 2017-2018. We focused our analysis on examining the differences across age groups, sub-disciplines of science, and sectors of employment. FINDINGS Most respondents displayed what we describe as high and mediocre risk data practices by storing their data on their personal computer, departmental servers or USB drives. Respondents appeared to be satisfied with short-term storage solutions; however, only half of them are satisfied with available mechanisms for storing data beyond the life of the process. Data sharing and data reuse were viewed positively over 85% of respondents admitted they would be willing to share their data with others and said they would use data collected by others if it could be easily accessed. A vast majority of respondents felt that the lack of access to data generated by other researchers or institutions was a major impediment to progress in science at large, yet only about a half thought that it restricted their own ability to answer scientific questions. Although attitudes towards data sharing and data use and reuse are mostly positive, practice does not always support data storage, sharing, and future reuse. Assistance through data managers or data librarians, readily available data repositories for both long-term and short-term storage, and educational programs for both awareness and to help engender good data practices are clearly needed.Large expansions of microsatellite DNA cause several neurological diseases. In Spinocerebellar ataxia type 10 (SCA10), the repeat interruptions change disease phenotype; an (ATTCC)n or a (ATCCT)n/(ATCCC)n interruption within the (ATTCT)n repeat is associated with the robust phenotype of ataxia and epilepsy while mostly pure (ATTCT)n may have reduced penetrance. Large repeat expansions of SCA10, and many other microsatellite expansions, can exceed 10,000 base pairs (bp) in size. Conventional next generation sequencing (NGS) technologies are ineffective in determining internal sequence contents or size of these expanded repeats. Using repeat primed PCR (RP-PCR) in conjunction with a high-sensitivity pulsed-field capillary electrophoresis fragment analyzer (FEMTO-Pulse, Agilent, Santa Clara, CA) (RP-FEMTO hereafter), we successfully determined sequence content of large expansion repeats in genomic DNA of SCA10 patients and transformed yeast artificial chromosomes containing SCA10 repeats. This RP-FEMTO is a simple and economical methodology which could complement emerging NGS for very long sequence reads such as Single Molecule, Real-Time (SMRT) and nanopore sequencing technologies.Current efforts to improve muscle performance are focused on muscle trophism via inhibition of the myostatin pathway however they have been unsuccessful in the clinic to date. In this study, a novel protein has been created by combining the soluble activin receptor, a strong myostatin inhibitor, to the C-terminal agrin nLG3 domain (ActR-Fc-nLG3) involved in the development and maintenance of neuromuscular junctions. Both domains are connected via the constant region of an Igg1 monoclonal antibody. Surprisingly, young male **** treated with ActR-Fc-nLG3 showed a remarkably increased endurance in the rotarod test, significantly longer than the single domain compounds ActR-Fc and Fc-nLG3 treated animals. This increase in endurance was accompanied by only a moderate increase in body weights and wet muscle weights of ActR-Fc-nLG3 treated animals and were lower than expected. The myostatin inhibitor ActR-Fc induced, as expected, a highly significant increase in body and muscle weights compared to control animals and ActR-Fc-nLG3 treated animals. Moreover, the prolonged endurance effect was not observed when ActR-Fc and Fc-nLG3 were dosed simultaneously as a mixture and the body and muscle weights of these animals were very similar to ActR-Fc treated animals, indicating that both domains need to be on one molecule. https://www.selleckchem.com/products/6-benzylaminopurine.html Muscle morphology induced by ActR-Fc-nLG3 did not appear to be changed however, close examination of the neuromuscular junction showed significantly increased acetylcholine receptor surface area for ActR-Fc-nLG3 treated animals compared to controls. This result is consistent with published observations that endurance training in rats increased acetylcholine receptor quantity at neuromuscular junctions and provide evidence that improving nerve-muscle interaction could be an important factor for sustaining long term muscle activity.
By contrast, the birds, but not the primates tested, struggled to attend to multiple variables-where two apparatuses, two tools and two reward qualities were presented simultaneously-without extended experience. These findings indicate (1) in a similar manner to humans and orangutans, New Caledonian crows and Goffin's cockatoos can flexibly make profitable decisions in some decision-making tool-use tasks, though the birds may struggle when tasks become more complex; (2) children and orangutans may have a bias to use tools in situations where adults and other tool-making species do not.This study examined the socio-demographic factors associated with normal linear growth among pre-school children living in better-off households, using survey data from Ghana, Kenya, Nigeria, Mozambique and Democratic Republic of Congo (DRC). The primary outcome variable was child height-for-age z-scores (HAZ), categorised into HAZ≥-2SD (normal growth/not stunted) and HAZ less then -2 (stunted). Using logistic regression, we estimated adjusted odds ratios (aORs) of the factors associated with normal growth. Higher maternal weight (measured by body mass index) was associated with increased odds of normal growth in Mozambique, DRC, Kenya and Nigeria. A unit increase in maternal years of education was associated with increased odds in normal growth in DRC (aOR = 1.06, 95% CI = 1.03, 1.09), Ghana (aOR = 1.08, 95% CI = 1.04, 1.12), Mozambique (aOR = 1.08, 95% CI = 1.05, 1.11) and Nigeria (aOR = 1.07, 95% CI = 1.06, 1.08). A year increase in maternal age was positively associated with normal growth in all the five wth. In contrast, maternal parity, employment, and child sex and age are associated negatively with normal growth. Interventions to improve child growth should take into account these differential effects.BACKGROUND With data becoming a centerpiece of modern scientific discovery, data sharing by scientists is now a crucial element of scientific progress. This article aims to provide an in-depth examination of the practices and perceptions of data management, including data storage, data sharing, and data use and reuse by scientists around the world. METHODS The Usability and Assessment Working Group of DataONE, an NSF-funded environmental cyberinfrastructure project, distributed a survey to a multinational and multidisciplinary sample of scientific researchers in a two-waves approach in 2017-2018. We focused our analysis on examining the differences across age groups, sub-disciplines of science, and sectors of employment. FINDINGS Most respondents displayed what we describe as high and mediocre risk data practices by storing their data on their personal computer, departmental servers or USB drives. Respondents appeared to be satisfied with short-term storage solutions; however, only half of them are satisfied with available mechanisms for storing data beyond the life of the process. Data sharing and data reuse were viewed positively over 85% of respondents admitted they would be willing to share their data with others and said they would use data collected by others if it could be easily accessed. A vast majority of respondents felt that the lack of access to data generated by other researchers or institutions was a major impediment to progress in science at large, yet only about a half thought that it restricted their own ability to answer scientific questions. Although attitudes towards data sharing and data use and reuse are mostly positive, practice does not always support data storage, sharing, and future reuse. Assistance through data managers or data librarians, readily available data repositories for both long-term and short-term storage, and educational programs for both awareness and to help engender good data practices are clearly needed.Large expansions of microsatellite DNA cause several neurological diseases. In Spinocerebellar ataxia type 10 (SCA10), the repeat interruptions change disease phenotype; an (ATTCC)n or a (ATCCT)n/(ATCCC)n interruption within the (ATTCT)n repeat is associated with the robust phenotype of ataxia and epilepsy while mostly pure (ATTCT)n may have reduced penetrance. Large repeat expansions of SCA10, and many other microsatellite expansions, can exceed 10,000 base pairs (bp) in size. Conventional next generation sequencing (NGS) technologies are ineffective in determining internal sequence contents or size of these expanded repeats. Using repeat primed PCR (RP-PCR) in conjunction with a high-sensitivity pulsed-field capillary electrophoresis fragment analyzer (FEMTO-Pulse, Agilent, Santa Clara, CA) (RP-FEMTO hereafter), we successfully determined sequence content of large expansion repeats in genomic DNA of SCA10 patients and transformed yeast artificial chromosomes containing SCA10 repeats. This RP-FEMTO is a simple and economical methodology which could complement emerging NGS for very long sequence reads such as Single Molecule, Real-Time (SMRT) and nanopore sequencing technologies.Current efforts to improve muscle performance are focused on muscle trophism via inhibition of the myostatin pathway however they have been unsuccessful in the clinic to date. In this study, a novel protein has been created by combining the soluble activin receptor, a strong myostatin inhibitor, to the C-terminal agrin nLG3 domain (ActR-Fc-nLG3) involved in the development and maintenance of neuromuscular junctions. Both domains are connected via the constant region of an Igg1 monoclonal antibody. Surprisingly, young male mice treated with ActR-Fc-nLG3 showed a remarkably increased endurance in the rotarod test, significantly longer than the single domain compounds ActR-Fc and Fc-nLG3 treated animals. This increase in endurance was accompanied by only a moderate increase in body weights and wet muscle weights of ActR-Fc-nLG3 treated animals and were lower than expected. The myostatin inhibitor ActR-Fc induced, as expected, a highly significant increase in body and muscle weights compared to control animals and ActR-Fc-nLG3 treated animals. Moreover, the prolonged endurance effect was not observed when ActR-Fc and Fc-nLG3 were dosed simultaneously as a mixture and the body and muscle weights of these animals were very similar to ActR-Fc treated animals, indicating that both domains need to be on one molecule. https://www.selleckchem.com/products/6-benzylaminopurine.html Muscle morphology induced by ActR-Fc-nLG3 did not appear to be changed however, close examination of the neuromuscular junction showed significantly increased acetylcholine receptor surface area for ActR-Fc-nLG3 treated animals compared to controls. This result is consistent with published observations that endurance training in rats increased acetylcholine receptor quantity at neuromuscular junctions and provide evidence that improving nerve-muscle interaction could be an important factor for sustaining long term muscle activity.0 Commentarii 0 Distribuiri 72 Views 0 previzualizare -
te' from 'excessive' mobility and adequately identify injury risk in dancers. Overall, it is suggested that practitioners should use caution before using the FMS™ as a primary screening mechanism to identify collegiate dancers at overall or LE injury risk.
2.
2.
Inability to maintain proper alignment of the pelvis and femur due to gluteal muscle weakness has been associated with numerous lower extremity pathologies. Therefore, many lower extremity rehabilitation and injury prevention programs employ exercises that target gluteal muscle strength and activation. While information regarding muscle activation during exercises that are typically done in the beginning stages of rehabilitation is available, evidence regarding the gluteal muscle activity during more functional and advanced exercises used during later stages of rehabilitation is sparse.
To explore the recruitment of the gluteal muscles during jumping tasks in healthy participants to determine which jumping exercise best elicits gluteal muscle activation.
Prospective cohort design.
Eighteen healthy recreational athletes (23.5 ± 3.8 years, 8M/10F, 67.56 ± 3.2 inches, 66.73 ± 9.5 kg) completed three trials of four jumping tasks hurdle jump, split jump, V2 lateral jump, and cross-over jump in random ordere jump (76.8% MVIC) and split jump (73.1% MVIC). Only the hurdle jump produced greater than 70% MVIC for both GMed and GMax muscles.
The jumping task that resulted in greatest activation of the GMed was the crossover jump, while hurdle jump led to the greatest activation of the GMax. The high %MVIC for the GMed during the crossover jump may be attributed to lack of maximal effort or lack of motivation during performance of maximal contractions during the manual muscle testing. Alternatively, substantial co-contraction of core muscles during the crossover jumping task may have led to higher values.
2b Individual Cohort Study.
2b Individual Cohort Study.
A recently published Dutch practice guideline emphasizes criterion-based rehabilitation after anterior cruciate ligament reconstruction (ACLR) instead of time-based. As a consequence of this criterion-based rehabilitation, return to play is only suggested when athletes meet specific return to play (RTP) criteria.
The goal of this prospective observational study was to analyze if physical therapists adhere to ACLR practice guideline RTP criteria for testing and return to sport decisions, and to explore whether there is a difference in adherence between physical therapists specialized in sports versus those who are not.
When the treating physical therapist cleared an athlete for RTP after ACLR, the primary researcher performed RTP measurements according to the ACLR practice guideline to investigate if all nine quantitative and qualitative RTP criteria were met.
Of the 158 athletes (54 females and 104 males, mean age 24 ± 6 years, 12 ± 3 months after surgery), 69 (44%) had performed the RTP measurements with their primary physical therapist. Of the athletes tested by their primary physical therapist 23% met all RTP criteria compared to 10% of the athletes who were not tested at all by their primary physical therapist (p = 0.026). Of the athletes rehabilitating with a sports physical therapist, 52% had been tested by their primary physical therapist compared to 34% of the athletes rehabilitating with a non-sports physical therapist (p = 0.024).
Only 44% of the athletes were tested according to the guideline RTP criteria and only 23% of them were given an RTP advice consistent with the ACLR guideline. Although sports physical therapists adhered to the guideline more often than non-sports physical therapists, the adherence is still alarmingly low. More attention for the implementation of ACLR guidelines and RTP criteria is needed.
Therapy, level 2b.
Therapy, level 2b.
Quadriceps weakness is a predictor of long-term knee function and strength recovery can vary from months to years after anterior cruciate ligament reconstruction (ACLR). However, few studies evaluate quadriceps strength and self-reported function within the first several weeks after ACLR.
To examine changes over time in quadriceps strength symmetry, quadriceps peak torque, and self-reported knee function prior to and at six, 12, and 24 weeks post-ACLR. https://www.selleckchem.com/products/estradiol-benzoate.html The hypotheses were 1) quadriceps strength symmetry, bilateral quadriceps peak torque, and patient-reported function would improve over time from pre-ACLR to 24 weeks post-ACLR and 2) significant improvements in patient-reported function, but not strength symmetry, would occur between time points.
Prospective, cohort study.
Thirty participants completed four testing sessions pre-surgery and six, 12, and 24 weeks post-ACLR. Isometric quadriceps strength testing was performed at six weeks and isokinetic quadriceps strength was measured at all other testinUninvolved limb quadriceps peak torque did not change across any time point (p≥0.18).
Patient-reported knee function increased between six and 24 weeks post-ACLR, while increases in involved limb quadriceps strength and quadriceps strength symmetry were not noted until 12-24 weeks post-ACLR.
2b, individual cohort study.
2b, individual cohort study.
Dynamic knee valgus has been associated with patellofemoral pain (PFP) during high-level tasks, however, repeated lower-level stresses may be an alternative pain mechanism. The primary purpose of the current study was to examine the consistency of dynamic knee valgus and task-elicited pain demonstrated by females with PFP across four common functional tasks (stair ascent, stair descent, sit-to-stand, and stand-to-sit). A secondary purpose was to assess the correlation between the clinical test of single-limb squat and functional tasks.
Females with patellofemoral pain will demonstrate a positive relationship in magnitude of dynamic knee valgus and task-elicited pain across functional tasks. Individuals who demonstrated greater dynamic knee valgus and task-elicited pain during the clinical test of single-limb squat would demonstrate greater dynamic knee valgus and task elicited pain during stair ascent/descent and sit-to-stand/stand-to-sit tasks.
Cross-sectional study; secondary analysis of a feasibility intervention study.
te' from 'excessive' mobility and adequately identify injury risk in dancers. Overall, it is suggested that practitioners should use caution before using the FMS™ as a primary screening mechanism to identify collegiate dancers at overall or LE injury risk. 2. 2. Inability to maintain proper alignment of the pelvis and femur due to gluteal muscle weakness has been associated with numerous lower extremity pathologies. Therefore, many lower extremity rehabilitation and injury prevention programs employ exercises that target gluteal muscle strength and activation. While information regarding muscle activation during exercises that are typically done in the beginning stages of rehabilitation is available, evidence regarding the gluteal muscle activity during more functional and advanced exercises used during later stages of rehabilitation is sparse. To explore the recruitment of the gluteal muscles during jumping tasks in healthy participants to determine which jumping exercise best elicits gluteal muscle activation. Prospective cohort design. Eighteen healthy recreational athletes (23.5 ± 3.8 years, 8M/10F, 67.56 ± 3.2 inches, 66.73 ± 9.5 kg) completed three trials of four jumping tasks hurdle jump, split jump, V2 lateral jump, and cross-over jump in random ordere jump (76.8% MVIC) and split jump (73.1% MVIC). Only the hurdle jump produced greater than 70% MVIC for both GMed and GMax muscles. The jumping task that resulted in greatest activation of the GMed was the crossover jump, while hurdle jump led to the greatest activation of the GMax. The high %MVIC for the GMed during the crossover jump may be attributed to lack of maximal effort or lack of motivation during performance of maximal contractions during the manual muscle testing. Alternatively, substantial co-contraction of core muscles during the crossover jumping task may have led to higher values. 2b Individual Cohort Study. 2b Individual Cohort Study. A recently published Dutch practice guideline emphasizes criterion-based rehabilitation after anterior cruciate ligament reconstruction (ACLR) instead of time-based. As a consequence of this criterion-based rehabilitation, return to play is only suggested when athletes meet specific return to play (RTP) criteria. The goal of this prospective observational study was to analyze if physical therapists adhere to ACLR practice guideline RTP criteria for testing and return to sport decisions, and to explore whether there is a difference in adherence between physical therapists specialized in sports versus those who are not. When the treating physical therapist cleared an athlete for RTP after ACLR, the primary researcher performed RTP measurements according to the ACLR practice guideline to investigate if all nine quantitative and qualitative RTP criteria were met. Of the 158 athletes (54 females and 104 males, mean age 24 ± 6 years, 12 ± 3 months after surgery), 69 (44%) had performed the RTP measurements with their primary physical therapist. Of the athletes tested by their primary physical therapist 23% met all RTP criteria compared to 10% of the athletes who were not tested at all by their primary physical therapist (p = 0.026). Of the athletes rehabilitating with a sports physical therapist, 52% had been tested by their primary physical therapist compared to 34% of the athletes rehabilitating with a non-sports physical therapist (p = 0.024). Only 44% of the athletes were tested according to the guideline RTP criteria and only 23% of them were given an RTP advice consistent with the ACLR guideline. Although sports physical therapists adhered to the guideline more often than non-sports physical therapists, the adherence is still alarmingly low. More attention for the implementation of ACLR guidelines and RTP criteria is needed. Therapy, level 2b. Therapy, level 2b. Quadriceps weakness is a predictor of long-term knee function and strength recovery can vary from months to years after anterior cruciate ligament reconstruction (ACLR). However, few studies evaluate quadriceps strength and self-reported function within the first several weeks after ACLR. To examine changes over time in quadriceps strength symmetry, quadriceps peak torque, and self-reported knee function prior to and at six, 12, and 24 weeks post-ACLR. https://www.selleckchem.com/products/estradiol-benzoate.html The hypotheses were 1) quadriceps strength symmetry, bilateral quadriceps peak torque, and patient-reported function would improve over time from pre-ACLR to 24 weeks post-ACLR and 2) significant improvements in patient-reported function, but not strength symmetry, would occur between time points. Prospective, cohort study. Thirty participants completed four testing sessions pre-surgery and six, 12, and 24 weeks post-ACLR. Isometric quadriceps strength testing was performed at six weeks and isokinetic quadriceps strength was measured at all other testinUninvolved limb quadriceps peak torque did not change across any time point (p≥0.18). Patient-reported knee function increased between six and 24 weeks post-ACLR, while increases in involved limb quadriceps strength and quadriceps strength symmetry were not noted until 12-24 weeks post-ACLR. 2b, individual cohort study. 2b, individual cohort study. Dynamic knee valgus has been associated with patellofemoral pain (PFP) during high-level tasks, however, repeated lower-level stresses may be an alternative pain mechanism. The primary purpose of the current study was to examine the consistency of dynamic knee valgus and task-elicited pain demonstrated by females with PFP across four common functional tasks (stair ascent, stair descent, sit-to-stand, and stand-to-sit). A secondary purpose was to assess the correlation between the clinical test of single-limb squat and functional tasks. Females with patellofemoral pain will demonstrate a positive relationship in magnitude of dynamic knee valgus and task-elicited pain across functional tasks. Individuals who demonstrated greater dynamic knee valgus and task-elicited pain during the clinical test of single-limb squat would demonstrate greater dynamic knee valgus and task elicited pain during stair ascent/descent and sit-to-stand/stand-to-sit tasks. Cross-sectional study; secondary analysis of a feasibility intervention study.0 Commentarii 0 Distribuiri 79 Views 0 previzualizare -
To accelerate the reduction in tuberculosis (TB) incidence, it is necessary to optimize the use of innovative tools and approaches available within a local context. This study evaluated the use of an existing network of community health workers (CHW) for active case finding, in combination with mobile chest X-ray (CXR) screening events and the expansion of Xpert MTB/RIF testing eligibility, in order to reach people with TB who had been missed by the current system. A controlled intervention study was conducted from January 2018 to March 2019 in five intervention and four control districts of two low to medium TB burden cities in Viet Nam. CHWs screened and referred eligible persons for CXR to TB care facilities or mobile screening events in the community. The initial diagnostic test was Xpert MTB/RIF for persons with parenchymal abnormalities suggestive of TB on CXR or otherwise on smear microscopy. We analyzed the TB care cascade by calculating the yield and number needed to screen (NNS), estimated the impact on TB notifications and conducted a pre-/postintervention comparison of TB notification rates using controlled, interrupted time series (ITS) analyses. We screened 30,336 individuals in both cities to detect and treat 243 individuals with TB, 88.9% of whom completed treatment successfully. All forms of TB notifications rose by +18.3% (95% CI +15.8%, +20.8%). The ITS detected a significant postintervention step-increase in the intervention area for all-form TB notification rates (IRR(β6) = 1.221 (95% CI 1.011, 1.475); p = 0.038). The combined use of CHWs for active case findings and mobile CXR screening expanded the access to and uptake of Xpert MTB/RIF testing and resulted in a significant increase in TB notifications. This model could serve as a blueprint for expansion throughout Vietnam. Moreover, the results demonstrate the need to optimize the use of the best available tools and approaches in order to end TB.Climate change strongly impacts the agricultural sector in West Africa, threatening food security and nutrition, particularly for populations with the least adaptive capacity. https://www.selleckchem.com/products/aminooxyacetic-acid-hemihydrochloride.html Little is known about national climate change policies in the region. This systematic review identifies and analyses climate change policy documents in all 16 West African countries (1) What are the existing climate change adaptation policies publicly available? (2) Which topics are addressed? (3) How are agriculture and food security framed and addressed? Following PRISMA guidelines, PubMed and Google scholar as key databases were searched with an extensive grey literature search. Keywords for searches were combinations of "Africa", "Climate Change", and "National Policy/Plan/Strategy/Guideline". Fifteen countries have at least one national policy document on climate change in the frame of our study. Nineteen policy documents covered seven key sectors (energy, agriculture, water resources, health, forestry, infrastructure, and educatioental ecology. They reflect barriers to adaptation especially for small-scale subsistence farmers with increased climate change vulnerabilities. The study has shown that most West African countries have climate change policies. Nevertheless, key questions remain unanswered, and demand for further research, e.g., on evaluating the implementation in the respective countries, persists.It is proposed that "crystal memory", observed in a discontinuous solid-liquid phase transition of saturated triacylglycerol (TAG) molecules, is due to the coexistence of solid TAG crystalline phases and a liquid TAG phase, in a superheated metastable regime. Such a coexistence has been detected. Solid crystals can act as heterogeneous nuclei onto which molecules can condense as the temperature is lowered. We outlined a mathematical model, with a single phase transition, that shows how the time-temperature observations can be explained, makes predictions, and relates them to recent experimental data. A modified Vogel-Fulcher-Tammann (VFT) equation is used to predict time-temperature relations for the observation of "crystal memory" and to show boundaries beyond which "crystal memory" is not observed. A plot of the lifetime of a metastable state versus temperature, using the modified VFT equation, agrees with recent time-temperature data. The model can be falsified through its predictions the model possesses a critical point and we outline a procedure describing how it could be observed by changing the hydrocarbon chain length. We make predictions about how thermodynamic functions will change as the critical point is reached and as the system enters a crossover regime. The model predicts that the phenomenon of "crystal memory" will not be observed unless the system is cooled from a superheated metastable regime associated with a discontinuous phase transition.Fibromyalgia syndrome is a chronic rheumatic disorder characterized by generalized and widespread musculoskeletal pain. It is associated with several secondary symptoms such as psychological and pain-specific distress, which can directly impact daily functioning and quality of life, like anxiety and depression. The Ganoderma lucidum (GL) mushroom seems to be able to improve fibromyalgia symptoms, including depression and pain. The purpose of the study is to evaluate the effects of GL on happiness, depression, satisfaction with life, and health-related quality of life in women with fibromyalgia. A double-blind, randomized placebo pilot trial was carried out, with one group taking 6 g/day of micro-milled GL carpophores for 6 weeks, during which the second group took a placebo. Our results did not show any statistically significant between-group differences, although a distinct trend of improved levels of happiness and satisfaction with life and reduced depression were evident at the end of treatment compared to the baseline in the GL group. However, due to the limitations of the study protocol, additional studies are necessary to confirm these findings.Massive multiple input multiple output (MIMO), also known as a very large-scale MIMO, is an emerging technology in wireless communications that increases capacity compared to MIMO systems. The massive MIMO communication technique is currently forming a major part of ongoing research. The main issue for massive MIMO improvements depends on the number of transmitting antennas to increase the data rate and minimize bit error rate (BER). To enhance the data rate and BER, new coding and modulation techniques are required. In this paper, a generalized spatial modulation (GSM) with antenna grouping space time coding technique (STC) is proposed. The proposed GSM-STC technique is based on space time coding of two successive GSM-modulated data symbols on two subgroups of antennas to improve data rate and to minimize BER. Moreover, the proposed GSM-STC system can offer spatial diversity gains and can also increase the reliability of the wireless channel by providing replicas of the received signal. The simulation results show that GSM-STC achieves better performance compared to conventional GSM techniques in terms of data rate and BER, leading to good potential for massive MIMO by using subgroups of antennas.
To accelerate the reduction in tuberculosis (TB) incidence, it is necessary to optimize the use of innovative tools and approaches available within a local context. This study evaluated the use of an existing network of community health workers (CHW) for active case finding, in combination with mobile chest X-ray (CXR) screening events and the expansion of Xpert MTB/RIF testing eligibility, in order to reach people with TB who had been missed by the current system. A controlled intervention study was conducted from January 2018 to March 2019 in five intervention and four control districts of two low to medium TB burden cities in Viet Nam. CHWs screened and referred eligible persons for CXR to TB care facilities or mobile screening events in the community. The initial diagnostic test was Xpert MTB/RIF for persons with parenchymal abnormalities suggestive of TB on CXR or otherwise on smear microscopy. We analyzed the TB care cascade by calculating the yield and number needed to screen (NNS), estimated the impact on TB notifications and conducted a pre-/postintervention comparison of TB notification rates using controlled, interrupted time series (ITS) analyses. We screened 30,336 individuals in both cities to detect and treat 243 individuals with TB, 88.9% of whom completed treatment successfully. All forms of TB notifications rose by +18.3% (95% CI +15.8%, +20.8%). The ITS detected a significant postintervention step-increase in the intervention area for all-form TB notification rates (IRR(β6) = 1.221 (95% CI 1.011, 1.475); p = 0.038). The combined use of CHWs for active case findings and mobile CXR screening expanded the access to and uptake of Xpert MTB/RIF testing and resulted in a significant increase in TB notifications. This model could serve as a blueprint for expansion throughout Vietnam. Moreover, the results demonstrate the need to optimize the use of the best available tools and approaches in order to end TB.Climate change strongly impacts the agricultural sector in West Africa, threatening food security and nutrition, particularly for populations with the least adaptive capacity. https://www.selleckchem.com/products/aminooxyacetic-acid-hemihydrochloride.html Little is known about national climate change policies in the region. This systematic review identifies and analyses climate change policy documents in all 16 West African countries (1) What are the existing climate change adaptation policies publicly available? (2) Which topics are addressed? (3) How are agriculture and food security framed and addressed? Following PRISMA guidelines, PubMed and Google scholar as key databases were searched with an extensive grey literature search. Keywords for searches were combinations of "Africa", "Climate Change", and "National Policy/Plan/Strategy/Guideline". Fifteen countries have at least one national policy document on climate change in the frame of our study. Nineteen policy documents covered seven key sectors (energy, agriculture, water resources, health, forestry, infrastructure, and educatioental ecology. They reflect barriers to adaptation especially for small-scale subsistence farmers with increased climate change vulnerabilities. The study has shown that most West African countries have climate change policies. Nevertheless, key questions remain unanswered, and demand for further research, e.g., on evaluating the implementation in the respective countries, persists.It is proposed that "crystal memory", observed in a discontinuous solid-liquid phase transition of saturated triacylglycerol (TAG) molecules, is due to the coexistence of solid TAG crystalline phases and a liquid TAG phase, in a superheated metastable regime. Such a coexistence has been detected. Solid crystals can act as heterogeneous nuclei onto which molecules can condense as the temperature is lowered. We outlined a mathematical model, with a single phase transition, that shows how the time-temperature observations can be explained, makes predictions, and relates them to recent experimental data. A modified Vogel-Fulcher-Tammann (VFT) equation is used to predict time-temperature relations for the observation of "crystal memory" and to show boundaries beyond which "crystal memory" is not observed. A plot of the lifetime of a metastable state versus temperature, using the modified VFT equation, agrees with recent time-temperature data. The model can be falsified through its predictions the model possesses a critical point and we outline a procedure describing how it could be observed by changing the hydrocarbon chain length. We make predictions about how thermodynamic functions will change as the critical point is reached and as the system enters a crossover regime. The model predicts that the phenomenon of "crystal memory" will not be observed unless the system is cooled from a superheated metastable regime associated with a discontinuous phase transition.Fibromyalgia syndrome is a chronic rheumatic disorder characterized by generalized and widespread musculoskeletal pain. It is associated with several secondary symptoms such as psychological and pain-specific distress, which can directly impact daily functioning and quality of life, like anxiety and depression. The Ganoderma lucidum (GL) mushroom seems to be able to improve fibromyalgia symptoms, including depression and pain. The purpose of the study is to evaluate the effects of GL on happiness, depression, satisfaction with life, and health-related quality of life in women with fibromyalgia. A double-blind, randomized placebo pilot trial was carried out, with one group taking 6 g/day of micro-milled GL carpophores for 6 weeks, during which the second group took a placebo. Our results did not show any statistically significant between-group differences, although a distinct trend of improved levels of happiness and satisfaction with life and reduced depression were evident at the end of treatment compared to the baseline in the GL group. However, due to the limitations of the study protocol, additional studies are necessary to confirm these findings.Massive multiple input multiple output (MIMO), also known as a very large-scale MIMO, is an emerging technology in wireless communications that increases capacity compared to MIMO systems. The massive MIMO communication technique is currently forming a major part of ongoing research. The main issue for massive MIMO improvements depends on the number of transmitting antennas to increase the data rate and minimize bit error rate (BER). To enhance the data rate and BER, new coding and modulation techniques are required. In this paper, a generalized spatial modulation (GSM) with antenna grouping space time coding technique (STC) is proposed. The proposed GSM-STC technique is based on space time coding of two successive GSM-modulated data symbols on two subgroups of antennas to improve data rate and to minimize BER. Moreover, the proposed GSM-STC system can offer spatial diversity gains and can also increase the reliability of the wireless channel by providing replicas of the received signal. The simulation results show that GSM-STC achieves better performance compared to conventional GSM techniques in terms of data rate and BER, leading to good potential for massive MIMO by using subgroups of antennas.0 Commentarii 0 Distribuiri 77 Views 0 previzualizare
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