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  • We performed cryogenic ion mobility-mass spectrometry (IM-MS) to study conformations of dibenzo-crown-ether complexes with Na+ and K+ ions at 86 K in the gas phase. Four dibenzo-crown-ethers (dibenzo-18-crown-6, dibenzo-21-crown-7, dibenzo-24-crown-8, and dibenzo-30-crown-10) with different cavity ring sizes were investigated. For dibenzo-18-crown-6 complexes with Na+ and K+, only one type of conformer was assigned by comparing the experimental collision cross sections with those predicted theoretically for candidate structures. In this conformer, the distance between two benzene rings in the complexes was long due to the open form of the dibenzo-18-crown-6. This open conformer was consistent with the previous laser spectroscopic studies of the cold complex ions in the gas phase. For dibenzo-21-crown-7 and dibenzo-24-crown-8 complexes with Na+ and K+, two types of conformers were clearly separated by IM-MS. These two conformer types were assigned to "open" and "closed" forms in which benzene-benzene distances were long and short, respectively. Observed relative abundances of the open and closed conformers qualitatively agreed with the Boltzmann distribution using Gibbs energies of the conformers calculated by quantum chemical calculations. For the Na+(dibenzo-30-crown-10) complex, open and closed conformers were also observed in IM-MS. On the other hand, only the closed conformer was observed for the K+(dibenzo-30-crown-10) complex. This closed conformer was similar to the "wraparound" structure, which was proposed in the previous studies in the solution. In conclusion, the closed conformers were formed by the deformation of flexible crown ethers with large cavity ring sizes. In addition, the diameter of the K+ ion was suitable to form the closed conformer by deformation of the molecular structure of dibenzo-30-crown-10.The hexahydride OsH6(PiPr3)2 competently catalyzes the hydration of aliphatic nitriles to amides. The main metal species under the catalytic conditions are the trihydride osmium(IV) amidate derivatives OsH3κ2-N,O-[HNC(O)R](PiPr3)2, which have been isolated and fully characterized for R = iPr and tBu. The rate of hydration is proportional to the concentrations of the catalyst precursor, nitrile, and water. When these experimental findings and density functional theory calculations are combined, the mechanism of catalysis has been established. Complexes OsH3κ2-N,O-[HNC(O)R](PiPr3)2 dissociate the carbonyl group of the chelate to afford κ1-N-amidate derivatives, which coordinate the nitrile. The subsequent attack of an external water molecule to both the C(sp) atom of the nitrile and the N atom of the amidate affords the amide and regenerates the κ1-N-amidate catalysts. The attack is concerted and takes place through a cyclic six-membered transition state, which involves Cnitrile···O-H···Namidate interactions. Before the attack, the free carbonyl group of the κ1-N-amidate ligand fixes the water molecule in the vicinity of the C(sp) atom of the nitrile.There is an urgent need for new treatments for visceral leishmaniasis (VL), a parasitic infection which impacts heavily large areas of East Africa, Asia, and South America. We previously reported on the discovery of GSK3494245/DDD01305143 (1) as a preclinical candidate for VL and, herein, we report on the medicinal chemistry program that led to its identification. A hit from a phenotypic screen was optimized to give a compound with in vivo efficacy, which was hampered by poor solubility and genotoxicity. The work on the original scaffold failed to lead to developable compounds, so an extensive scaffold-hopping exercise involving medicinal chemistry design, in silico profiling, and subsequent synthesis was utilized, leading to the preclinical candidate. The compound was shown to act via proteasome inhibition, and we report on the modeling of different scaffolds into a cryo-EM structure and the impact this has on our understanding of the series' structure-activity relationships.Small differences in physical and chemical properties of H2O and D2O, such as melting and boiling points or pKa, can be traced **** to a slightly stronger hydrogen bonding in heavy versus normal water. In particular, deuteration reduces zero-point vibrational energies as a demonstration of nuclear quantum effects. In principle, computationally demanding quantum molecular dynamics is required to model such effects. However, as already demonstrated by Feynmann and Hibbs, zero-point vibrations can be effectively accounted for by modifying the interaction potential within classical dynamics. In the spirit of the Feymann-Hibbs approach, we develop here two water models for classical molecular dynamics by fitting experimental differences between H2O and D2O. We show that a three-site SPCE-based model accurately reproduces differences between properties of the two water isotopes, with a four-site TIP4P-2005/based model in addition capturing also the absolute values of key properties of heavy water. https://www.selleckchem.com/products/uamc-3203.html The present models are computationally simple enough to allow for extensive simulations of biomolecules in heavy water relevant, for example, for experimental techniques such as NMR or neutron scattering.The rational design principles established for metal-organic frameworks (MOFs) allow clear structure-property relationships, fueling expansive growth for energy storage and conversion, catalysis, and beyond. However, these design principles are based on the assumption of compositional and structural rigidity, as measured crystallographically. Such idealization of MOF structures overlooks subtle chemical aspects that can lead to departures from structure-based chemical intuition. In this Perspective, we identify unexpected behavior of MOFs through literature examples. Based on this analysis, we conclude that departures from ideality are not uncommon. Whereas linker topology and metal coordination geometry are useful starting points for understanding MOF properties, we anticipate that deviations from the idealized crystal representation will be necessary to explain important and unexpected behaviors. Although this realization reinforces the notion that MOFs are highly complex materials, it should also stimulate a broader reexamination of the literature to identify corollaries to existing design rules and reveal new structure-property relationships.
    We performed cryogenic ion mobility-mass spectrometry (IM-MS) to study conformations of dibenzo-crown-ether complexes with Na+ and K+ ions at 86 K in the gas phase. Four dibenzo-crown-ethers (dibenzo-18-crown-6, dibenzo-21-crown-7, dibenzo-24-crown-8, and dibenzo-30-crown-10) with different cavity ring sizes were investigated. For dibenzo-18-crown-6 complexes with Na+ and K+, only one type of conformer was assigned by comparing the experimental collision cross sections with those predicted theoretically for candidate structures. In this conformer, the distance between two benzene rings in the complexes was long due to the open form of the dibenzo-18-crown-6. This open conformer was consistent with the previous laser spectroscopic studies of the cold complex ions in the gas phase. For dibenzo-21-crown-7 and dibenzo-24-crown-8 complexes with Na+ and K+, two types of conformers were clearly separated by IM-MS. These two conformer types were assigned to "open" and "closed" forms in which benzene-benzene distances were long and short, respectively. Observed relative abundances of the open and closed conformers qualitatively agreed with the Boltzmann distribution using Gibbs energies of the conformers calculated by quantum chemical calculations. For the Na+(dibenzo-30-crown-10) complex, open and closed conformers were also observed in IM-MS. On the other hand, only the closed conformer was observed for the K+(dibenzo-30-crown-10) complex. This closed conformer was similar to the "wraparound" structure, which was proposed in the previous studies in the solution. In conclusion, the closed conformers were formed by the deformation of flexible crown ethers with large cavity ring sizes. In addition, the diameter of the K+ ion was suitable to form the closed conformer by deformation of the molecular structure of dibenzo-30-crown-10.The hexahydride OsH6(PiPr3)2 competently catalyzes the hydration of aliphatic nitriles to amides. The main metal species under the catalytic conditions are the trihydride osmium(IV) amidate derivatives OsH3κ2-N,O-[HNC(O)R](PiPr3)2, which have been isolated and fully characterized for R = iPr and tBu. The rate of hydration is proportional to the concentrations of the catalyst precursor, nitrile, and water. When these experimental findings and density functional theory calculations are combined, the mechanism of catalysis has been established. Complexes OsH3κ2-N,O-[HNC(O)R](PiPr3)2 dissociate the carbonyl group of the chelate to afford κ1-N-amidate derivatives, which coordinate the nitrile. The subsequent attack of an external water molecule to both the C(sp) atom of the nitrile and the N atom of the amidate affords the amide and regenerates the κ1-N-amidate catalysts. The attack is concerted and takes place through a cyclic six-membered transition state, which involves Cnitrile···O-H···Namidate interactions. Before the attack, the free carbonyl group of the κ1-N-amidate ligand fixes the water molecule in the vicinity of the C(sp) atom of the nitrile.There is an urgent need for new treatments for visceral leishmaniasis (VL), a parasitic infection which impacts heavily large areas of East Africa, Asia, and South America. We previously reported on the discovery of GSK3494245/DDD01305143 (1) as a preclinical candidate for VL and, herein, we report on the medicinal chemistry program that led to its identification. A hit from a phenotypic screen was optimized to give a compound with in vivo efficacy, which was hampered by poor solubility and genotoxicity. The work on the original scaffold failed to lead to developable compounds, so an extensive scaffold-hopping exercise involving medicinal chemistry design, in silico profiling, and subsequent synthesis was utilized, leading to the preclinical candidate. The compound was shown to act via proteasome inhibition, and we report on the modeling of different scaffolds into a cryo-EM structure and the impact this has on our understanding of the series' structure-activity relationships.Small differences in physical and chemical properties of H2O and D2O, such as melting and boiling points or pKa, can be traced back to a slightly stronger hydrogen bonding in heavy versus normal water. In particular, deuteration reduces zero-point vibrational energies as a demonstration of nuclear quantum effects. In principle, computationally demanding quantum molecular dynamics is required to model such effects. However, as already demonstrated by Feynmann and Hibbs, zero-point vibrations can be effectively accounted for by modifying the interaction potential within classical dynamics. In the spirit of the Feymann-Hibbs approach, we develop here two water models for classical molecular dynamics by fitting experimental differences between H2O and D2O. We show that a three-site SPCE-based model accurately reproduces differences between properties of the two water isotopes, with a four-site TIP4P-2005/based model in addition capturing also the absolute values of key properties of heavy water. https://www.selleckchem.com/products/uamc-3203.html The present models are computationally simple enough to allow for extensive simulations of biomolecules in heavy water relevant, for example, for experimental techniques such as NMR or neutron scattering.The rational design principles established for metal-organic frameworks (MOFs) allow clear structure-property relationships, fueling expansive growth for energy storage and conversion, catalysis, and beyond. However, these design principles are based on the assumption of compositional and structural rigidity, as measured crystallographically. Such idealization of MOF structures overlooks subtle chemical aspects that can lead to departures from structure-based chemical intuition. In this Perspective, we identify unexpected behavior of MOFs through literature examples. Based on this analysis, we conclude that departures from ideality are not uncommon. Whereas linker topology and metal coordination geometry are useful starting points for understanding MOF properties, we anticipate that deviations from the idealized crystal representation will be necessary to explain important and unexpected behaviors. Although this realization reinforces the notion that MOFs are highly complex materials, it should also stimulate a broader reexamination of the literature to identify corollaries to existing design rules and reveal new structure-property relationships.
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  • Understanding magnetically induced currents (****) in aromatic or metallic nanostructures is crucial for interpreting local magnetic shielding and NMR data. Direct measurements of the induced currents have been successful only in a few planar molecules but their indirect effects are seen in NMR shifts of probe nuclei. Here, we have implemented a numerically efficient method to calculate gauge-including **** in the formalism of auxiliary density functional theory. We analyze the currents in two experimentally synthesized gold-based, hydrogen-containing ligand-stabilized nanoclusters [HAu9(PPh3)8]2+ and [PtHAu8(PPh3)8]+. Both clusters have a similar octet configuration of Au(6s)-derived delocalized "superatomic" electrons. Surprisingly, Pt-doping in gold increases the diatropic response of the superatomic electrons to an external magnetic field and enhances the aromaticity of [PtHAu8(PPh3)8]+. This is manifested by a stronger shielding of the hydrogen proton in the metal core of the cluster as compared to [HAu9(PPh3)8]2+, causing a significant upfield shift in agreement with experimental proton NMR data measured for these two clusters. Our method allows the determination of local magnetic shielding properties for any component in large 3D nanostructures, opening the door for detailed interpretation of complex NMR spectra.Programmable magnetic field-free manipulation of perpendicular magnetization switching is essential for the development of ultralow-power spintronic devices. However, the magnetization in a centrosymmetric single-layer ferromagnetic film cannot be switched directly by passing an electrical current in itself. Here, we demonstrate a repeatable bulk spin-orbit torque (SOT) switching of the perpendicularly magnetized CoPt alloy single-layer films by introducing a composition gradient in the thickness direction to break the inversion symmetry. Experimental results reveal that the bulk SOT-induced effective field on the domain walls leads to the domain walls motion and magnetization switching. Moreover, magnetic field-free perpendicular magnetization switching caused by SOT and its switching polarity (clockwise or counterclockwise) can be reversibly controlled in the IrMn/Co/Ru/CoPt heterojunctions based on the exchange bias and interlayer exchange coupling. This unique composition gradient approach accompanied with electrically controllable SOT magnetization switching provides a promising strategy to access energy-efficient control of memory and logic devices.Percolation is an emblematic model to assess the robustness of interconnected systems when some of their components are corrupted. It is usually investigated in simple scenarios, such as the removal of the system's units in random order, or sequentially ordered by specific topological descriptors. However, in the vast majority of empirical applications, it is required to dismantle the network following more sophisticated protocols, for instance, by combining topological properties and non-topological node metadata. We propose a novel mathematical framework to fill this gap networks are enriched with features and their nodes are removed according to the importance in the feature space. We consider features of different nature, from ones related to the network construction to ones related to dynamical processes such as epidemic spreading. Our framework not only provides a natural generalization of percolation but, more importantly, offers an accurate way to test the robustness of networks in realistic scenarios.A pile of grains, even when at rest in a silo, can display fascinating properties. One of the most celebrated is the Janssen effect, named after the pioneering engineer who explained the pressure saturation at the bottom of a container filled with corn. This surprising behavior arises because of frictional interactions between the grains through a disordered network of contacts, and the vessel lateral walls, which partially support the weight of the column, decreasing its apparent mass. Here, we demonstrate control over frictional interactions using ferromagnetic grains and an external magnetic field. We show that the anisotropic pairwise interactions between magnetized grains result in a radial force along the walls, whose amplitude and direction is fully determined by the applied magnetic field. Such magnetic Janssen effect allows for the fine tuning of the granular column apparent mass. Our findings pave the way towards the design of functional jammed materials in confined geometries, via a further control of both their static and dynamic properties.In subduction zones, seismic slip at shallow crustal depths can lead to the generation of tsunamis. Large slip displacements during tsunamogenic earthquakes are attributed to the low coseismic shear strength of the fluid-saturated and non-lithified clay-rich fault rocks. However, because of experimental challenges in confining these materials, the physical processes responsible for the coseismic reduction in fault shear strength are poorly understood. Using a novel experimental setup, we measured pore fluid pressure during simulated seismic slip in clay-rich materials sampled from the deep oceanic drilling of the Pāpaku thrust (Hikurangi subduction zone, New Zealand). Here, we show that at seismic velocity, shear-induced dilatancy is followed by pressurisation of fluids. The thermal and mechanical pressurisation of fluids, enhanced by the low permeability of the fault, reduces the energy required to propagate earthquake rupture. We suggest that fluid-saturated clay-rich sediments, occurring at shallow depth in subduction zones, can promote earthquake rupture propagation and slip because of their low permeability and tendency to pressurise when sheared at seismic slip velocities.Wildfires are increasing globally in frequency, severity, and extent, but their impact on fluvial networks, and the resources they provide, remains unclear. We combine remote sensing of burn perimeter and severity, in-situ water quality monitoring, and longitudinal modeling to create the first large-scale, long-term estimates of stream+river length impacted by wildfire for the western US. https://www.selleckchem.com/products/ms4078.html We find that wildfires directly impact ~6% of the total stream+river length between 1984 and 2014, increasing at a rate of 342 km/year. When longitudinal propagation of water quality impacts is included, we estimate that wildfires affect ~11% of the total stream+river length. Our results indicate that wildfire activity is one of the largest drivers of aquatic impairment, though it is not routinely reported by regulatory agencies, as wildfire impacts on fluvial networks remain unconstrained. We identify key actions to address this knowledge gap and better understand the growing threat to fluvial networks, water security, and public health risks.
    Understanding magnetically induced currents (MICs) in aromatic or metallic nanostructures is crucial for interpreting local magnetic shielding and NMR data. Direct measurements of the induced currents have been successful only in a few planar molecules but their indirect effects are seen in NMR shifts of probe nuclei. Here, we have implemented a numerically efficient method to calculate gauge-including MICs in the formalism of auxiliary density functional theory. We analyze the currents in two experimentally synthesized gold-based, hydrogen-containing ligand-stabilized nanoclusters [HAu9(PPh3)8]2+ and [PtHAu8(PPh3)8]+. Both clusters have a similar octet configuration of Au(6s)-derived delocalized "superatomic" electrons. Surprisingly, Pt-doping in gold increases the diatropic response of the superatomic electrons to an external magnetic field and enhances the aromaticity of [PtHAu8(PPh3)8]+. This is manifested by a stronger shielding of the hydrogen proton in the metal core of the cluster as compared to [HAu9(PPh3)8]2+, causing a significant upfield shift in agreement with experimental proton NMR data measured for these two clusters. Our method allows the determination of local magnetic shielding properties for any component in large 3D nanostructures, opening the door for detailed interpretation of complex NMR spectra.Programmable magnetic field-free manipulation of perpendicular magnetization switching is essential for the development of ultralow-power spintronic devices. However, the magnetization in a centrosymmetric single-layer ferromagnetic film cannot be switched directly by passing an electrical current in itself. Here, we demonstrate a repeatable bulk spin-orbit torque (SOT) switching of the perpendicularly magnetized CoPt alloy single-layer films by introducing a composition gradient in the thickness direction to break the inversion symmetry. Experimental results reveal that the bulk SOT-induced effective field on the domain walls leads to the domain walls motion and magnetization switching. Moreover, magnetic field-free perpendicular magnetization switching caused by SOT and its switching polarity (clockwise or counterclockwise) can be reversibly controlled in the IrMn/Co/Ru/CoPt heterojunctions based on the exchange bias and interlayer exchange coupling. This unique composition gradient approach accompanied with electrically controllable SOT magnetization switching provides a promising strategy to access energy-efficient control of memory and logic devices.Percolation is an emblematic model to assess the robustness of interconnected systems when some of their components are corrupted. It is usually investigated in simple scenarios, such as the removal of the system's units in random order, or sequentially ordered by specific topological descriptors. However, in the vast majority of empirical applications, it is required to dismantle the network following more sophisticated protocols, for instance, by combining topological properties and non-topological node metadata. We propose a novel mathematical framework to fill this gap networks are enriched with features and their nodes are removed according to the importance in the feature space. We consider features of different nature, from ones related to the network construction to ones related to dynamical processes such as epidemic spreading. Our framework not only provides a natural generalization of percolation but, more importantly, offers an accurate way to test the robustness of networks in realistic scenarios.A pile of grains, even when at rest in a silo, can display fascinating properties. One of the most celebrated is the Janssen effect, named after the pioneering engineer who explained the pressure saturation at the bottom of a container filled with corn. This surprising behavior arises because of frictional interactions between the grains through a disordered network of contacts, and the vessel lateral walls, which partially support the weight of the column, decreasing its apparent mass. Here, we demonstrate control over frictional interactions using ferromagnetic grains and an external magnetic field. We show that the anisotropic pairwise interactions between magnetized grains result in a radial force along the walls, whose amplitude and direction is fully determined by the applied magnetic field. Such magnetic Janssen effect allows for the fine tuning of the granular column apparent mass. Our findings pave the way towards the design of functional jammed materials in confined geometries, via a further control of both their static and dynamic properties.In subduction zones, seismic slip at shallow crustal depths can lead to the generation of tsunamis. Large slip displacements during tsunamogenic earthquakes are attributed to the low coseismic shear strength of the fluid-saturated and non-lithified clay-rich fault rocks. However, because of experimental challenges in confining these materials, the physical processes responsible for the coseismic reduction in fault shear strength are poorly understood. Using a novel experimental setup, we measured pore fluid pressure during simulated seismic slip in clay-rich materials sampled from the deep oceanic drilling of the Pāpaku thrust (Hikurangi subduction zone, New Zealand). Here, we show that at seismic velocity, shear-induced dilatancy is followed by pressurisation of fluids. The thermal and mechanical pressurisation of fluids, enhanced by the low permeability of the fault, reduces the energy required to propagate earthquake rupture. We suggest that fluid-saturated clay-rich sediments, occurring at shallow depth in subduction zones, can promote earthquake rupture propagation and slip because of their low permeability and tendency to pressurise when sheared at seismic slip velocities.Wildfires are increasing globally in frequency, severity, and extent, but their impact on fluvial networks, and the resources they provide, remains unclear. We combine remote sensing of burn perimeter and severity, in-situ water quality monitoring, and longitudinal modeling to create the first large-scale, long-term estimates of stream+river length impacted by wildfire for the western US. https://www.selleckchem.com/products/ms4078.html We find that wildfires directly impact ~6% of the total stream+river length between 1984 and 2014, increasing at a rate of 342 km/year. When longitudinal propagation of water quality impacts is included, we estimate that wildfires affect ~11% of the total stream+river length. Our results indicate that wildfire activity is one of the largest drivers of aquatic impairment, though it is not routinely reported by regulatory agencies, as wildfire impacts on fluvial networks remain unconstrained. We identify key actions to address this knowledge gap and better understand the growing threat to fluvial networks, water security, and public health risks.
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  • ly associated with incrementally improved complication odds as well as reduced length of stay and a small decrease in overall hospitalization cost. LEVEL OF EVIDENCE 3.STUDY DESIGN Experimental Cadaveric Biomechanical Study. OBJECTIVE To establish an experimental procedure in cadavers to estimate joint stiffness/stability at CVJ region with various implant systems and to develop/validate an indigenous cost effective 3D -FEM (3 dimensional finite element model) of CVJ region. SUMMARY OF BACKGROUND DATA Finite element analysis (FEM) tools can provide estimates of internal stress and strain in response to external loading of various implant systems used in craniovertebral junction (CVJ) fixations. METHODS Experimental setup for conducting biomechanical movements on CVJ region of cadaver was developed using cost effective innovative tools. A manually actuated 7-DOF(degrees of freedom) parallel manipulator motion testing system (MA7DPM) was designed and developed to impart designed trajectories and to conduct various biomechanical motion studies at CVJ region for present study. RESULTS FEM model of CVJ region was developed and subsequently validated with CVJ morphometry data of 15 human subjects of Asian origin. Validated FEM was subjected to force motion studies at CVJ region. The force-motion maps obtained from the FEM studies were subsequently validated against biomechanical experiment results conducted in cadavers wherein three different implant fixations CONCLUSIONS. A cost effective biomechanical tool [which did not require decapitation of cadaveric head] and a customised chair [to place cadaver in sitting position during conduct of biomechanical movements simulating real life scenario] was indigenously designed and developed. Developed biomechanical tool (MA7DPM) for this study is likely to be useful for stress-testing analysis of various implant systems for individual patients undergoing surgery at CVJ region in near future. https://www.selleckchem.com/products/jnk-inhibitor-viii.html LEVEL OF EVIDENCE 5.STUDY DESIGN Retrospective analysis. OBJECTIVE To evaluate conditional survival after surgical resection for spinal chondrosarcoma patients. SUMMARY OF BACKGROUND DATA Survival estimates are usually reported as survival from the time of surgery, but survival probabilities can change over time. Conditional survival, which is a measure of prognosis for patients who have survived a defined period of time, may be more clinically precise and relevant. However, data on conditional survival for spinal chondrosarcoma patients after surgical resection are still lacking. METHODS We used the Surveillance, Epidemiology, and End Results (SEER) database to identify 436 spinal chondrosarcoma patients who underwent surgical resection from 1994 and 2013. Kaplan-Meier analyses and Cox regression modeling were performed to evaluate prognostic factors associated with overall survival. Five-year conditional survival (i.e. probability of surviving an additional 5 years, given that a patient has already survived x years) was calculondrosarcoma patients after surgical resection improves over time, especially for patients with initial high-risk characteristics. Information derived from conditional survival analysis may provide individualized approaches to surveillance and treatment of spinal chondrosarcoma. LEVEL OF EVIDENCE 4.STUDY DESIGN Retrospective cohort study. OBJECTIVE To evaluate the impact of incidental durotomy during spine surgery on the development of delirium in patients aged 65 and older. SUMMARY OF BACKGROUND DATA Delirium after spine surgery has been shown to increase the risk of adverse events, including morbidity and readmissions. Durotomy has previously been postulated to influence the risk of delirium, but this has not been explored in patients 65 and older, the demographic at greatest risk of developing delirium. METHODS We obtained clinical data on 766 patients, including 182 with incidental durotomy, from the Partners healthcare registry (2012-2019). Patients had their medical records abstracted and age, biologic sex, body mass index, smoking status, pre-operative diagnosis, use of a fusion-based procedure and number of co-morbidities were recorded. Our primary outcome was the development of delirium. Our primary predictor was incidental durotomy. We used logistic regression techniques to adjust for sociodemioration or impairment during post-operative management of a durotomy. LEVEL OF EVIDENCE 3.STUDY DESIGN Experimental animal study of treatment of Spinal cord injury (SCI). OBJECTIVE This report aims to evaluate the in vivo effects of Butylphthalide NBP) on SCI biology and to explore its potential mechanism. SUMMARY OF BACKGROUND DATA Spinal cord injury (SCI) causes great damage to humans. The inflammatory and reconstructive processes after SCI is regulated by activation of astroglial and microglial cells. Activated microglia/macrophages can be divided into M2 (anti-inflammatory) and M1 (pro-inflammatory) phenotypes. Butylphthalide (3-n-butylphthalide or NBP) treatment can significantly alleviate ischemic brain damage, and further study has confirmed that central neuroprotective effects can be realized by converting M1 polarized microglia/macrophages to the M2 phenotype. Thus far, it remains unknown whether NBP can modulate the transition of macrophages/microglia between the M1 and M2 phenotypes. METHOD We randomly divided male **** into three groups (sham group, SCI group, SCI+ NBP group). Molecula3.STUDY DESIGN Retrospective cohort. OBJECTIVE We aimed to assess the changes in adjacent segmental lordosis across the intervertebral disc space following single level Posterior Lumbar Interbody Fusion(PLIF). SUMMARY OF BACKGROUND DATA Adjacent segment degeneration is well documented following fusion surgery as are the spinopelvic parameters. What isn't known is the effect of fusion surgery on the adjacent segmental lordosis of the lumbar spine following PLIF. METHODS Preoperative and one-year postoperative erect lateral radiographs were analysed for lordotic angulation of all lumbar segments and Pelvic Incidence (PI) in patients undergoing L4/5 or L5/S1 PLIF. RESULTS 47 PLIFs achieved a mean of 7° increase in segmental lordosis at L4/5 (p 10° preoperatively, reducing to 4° postoperatively. CONCLUSIONS Segmental lordosis increased significantly at the PLIF level. At L5/S1 minimal overall lordosis change occurred however there was reduction in lordosis at adjacent levels representing reduced adjacent segment 'compensation'.
    ly associated with incrementally improved complication odds as well as reduced length of stay and a small decrease in overall hospitalization cost. LEVEL OF EVIDENCE 3.STUDY DESIGN Experimental Cadaveric Biomechanical Study. OBJECTIVE To establish an experimental procedure in cadavers to estimate joint stiffness/stability at CVJ region with various implant systems and to develop/validate an indigenous cost effective 3D -FEM (3 dimensional finite element model) of CVJ region. SUMMARY OF BACKGROUND DATA Finite element analysis (FEM) tools can provide estimates of internal stress and strain in response to external loading of various implant systems used in craniovertebral junction (CVJ) fixations. METHODS Experimental setup for conducting biomechanical movements on CVJ region of cadaver was developed using cost effective innovative tools. A manually actuated 7-DOF(degrees of freedom) parallel manipulator motion testing system (MA7DPM) was designed and developed to impart designed trajectories and to conduct various biomechanical motion studies at CVJ region for present study. RESULTS FEM model of CVJ region was developed and subsequently validated with CVJ morphometry data of 15 human subjects of Asian origin. Validated FEM was subjected to force motion studies at CVJ region. The force-motion maps obtained from the FEM studies were subsequently validated against biomechanical experiment results conducted in cadavers wherein three different implant fixations CONCLUSIONS. A cost effective biomechanical tool [which did not require decapitation of cadaveric head] and a customised chair [to place cadaver in sitting position during conduct of biomechanical movements simulating real life scenario] was indigenously designed and developed. Developed biomechanical tool (MA7DPM) for this study is likely to be useful for stress-testing analysis of various implant systems for individual patients undergoing surgery at CVJ region in near future. https://www.selleckchem.com/products/jnk-inhibitor-viii.html LEVEL OF EVIDENCE 5.STUDY DESIGN Retrospective analysis. OBJECTIVE To evaluate conditional survival after surgical resection for spinal chondrosarcoma patients. SUMMARY OF BACKGROUND DATA Survival estimates are usually reported as survival from the time of surgery, but survival probabilities can change over time. Conditional survival, which is a measure of prognosis for patients who have survived a defined period of time, may be more clinically precise and relevant. However, data on conditional survival for spinal chondrosarcoma patients after surgical resection are still lacking. METHODS We used the Surveillance, Epidemiology, and End Results (SEER) database to identify 436 spinal chondrosarcoma patients who underwent surgical resection from 1994 and 2013. Kaplan-Meier analyses and Cox regression modeling were performed to evaluate prognostic factors associated with overall survival. Five-year conditional survival (i.e. probability of surviving an additional 5 years, given that a patient has already survived x years) was calculondrosarcoma patients after surgical resection improves over time, especially for patients with initial high-risk characteristics. Information derived from conditional survival analysis may provide individualized approaches to surveillance and treatment of spinal chondrosarcoma. LEVEL OF EVIDENCE 4.STUDY DESIGN Retrospective cohort study. OBJECTIVE To evaluate the impact of incidental durotomy during spine surgery on the development of delirium in patients aged 65 and older. SUMMARY OF BACKGROUND DATA Delirium after spine surgery has been shown to increase the risk of adverse events, including morbidity and readmissions. Durotomy has previously been postulated to influence the risk of delirium, but this has not been explored in patients 65 and older, the demographic at greatest risk of developing delirium. METHODS We obtained clinical data on 766 patients, including 182 with incidental durotomy, from the Partners healthcare registry (2012-2019). Patients had their medical records abstracted and age, biologic sex, body mass index, smoking status, pre-operative diagnosis, use of a fusion-based procedure and number of co-morbidities were recorded. Our primary outcome was the development of delirium. Our primary predictor was incidental durotomy. We used logistic regression techniques to adjust for sociodemioration or impairment during post-operative management of a durotomy. LEVEL OF EVIDENCE 3.STUDY DESIGN Experimental animal study of treatment of Spinal cord injury (SCI). OBJECTIVE This report aims to evaluate the in vivo effects of Butylphthalide NBP) on SCI biology and to explore its potential mechanism. SUMMARY OF BACKGROUND DATA Spinal cord injury (SCI) causes great damage to humans. The inflammatory and reconstructive processes after SCI is regulated by activation of astroglial and microglial cells. Activated microglia/macrophages can be divided into M2 (anti-inflammatory) and M1 (pro-inflammatory) phenotypes. Butylphthalide (3-n-butylphthalide or NBP) treatment can significantly alleviate ischemic brain damage, and further study has confirmed that central neuroprotective effects can be realized by converting M1 polarized microglia/macrophages to the M2 phenotype. Thus far, it remains unknown whether NBP can modulate the transition of macrophages/microglia between the M1 and M2 phenotypes. METHOD We randomly divided male mice into three groups (sham group, SCI group, SCI+ NBP group). Molecula3.STUDY DESIGN Retrospective cohort. OBJECTIVE We aimed to assess the changes in adjacent segmental lordosis across the intervertebral disc space following single level Posterior Lumbar Interbody Fusion(PLIF). SUMMARY OF BACKGROUND DATA Adjacent segment degeneration is well documented following fusion surgery as are the spinopelvic parameters. What isn't known is the effect of fusion surgery on the adjacent segmental lordosis of the lumbar spine following PLIF. METHODS Preoperative and one-year postoperative erect lateral radiographs were analysed for lordotic angulation of all lumbar segments and Pelvic Incidence (PI) in patients undergoing L4/5 or L5/S1 PLIF. RESULTS 47 PLIFs achieved a mean of 7° increase in segmental lordosis at L4/5 (p 10° preoperatively, reducing to 4° postoperatively. CONCLUSIONS Segmental lordosis increased significantly at the PLIF level. At L5/S1 minimal overall lordosis change occurred however there was reduction in lordosis at adjacent levels representing reduced adjacent segment 'compensation'.
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  • The retrieval time is of the establishment of the database to January 31, 2021. Two evaluators screens, extract and evaluate the literature, and the data are analyzed by RevMan5.3 software.

    The purpose of this study is to evaluate the effect of continuous nursing on the quality of life of hemodialysis patients by the MOS item short from health survey, exercise of self-care agency, and the incidence of complications.

    This study will provide reliable evidence for the application of continuous nursing in hemodialysis patients.

    DOI 10.17605/OSF.IO/HZKUA.
    DOI 10.17605/OSF.IO/HZKUA.
    To systematically review and evaluate the safety, advantages and clinical application value of laparo-endoscopic single-site surgery (LESS) for endometrial cancer by comparing it with conventional laparoscopic surgery (CLS).

    We conducted a systematic review of the published literature comparing LESS with CLS in the treatment of endometrial cancer. English databases including PubMed, Embase, Ovid, and the Cochrane Library and Chinese databases including Chinese National Knowledge Infrastructure, Wanfang and China Biology Medicine were searched for eligible observational studies up to July 10, 2019. We then evaluated the quality of the selected comparative studies before performing a meta-analysis using the RevMan 5.3 software. The complications, surgical time, blood loss during surgery, postoperative length of hospital stay and number of lymph nodes removed during surgery were compared between the 2 surgical approaches.

    Four studies with 234 patients were finally included in this meta-analysis. We found 53, 95% CI (-3.22 to 2.16), P = .70, I2 = 83%)]. However, patients treated with LESS had more pelvic lymph nodes removed during surgery than those treated with CLS (MD 3.33, 95% CI 1.05-5.62, P = .004, I2 = 32%).

    Compared with CLS, LESS did not reduce the incidence of complications or shorten postoperative hospital stay. Nor did it increase surgical time or the amount of bleeding during surgery. LESS can remove lymph nodes and ease postoperative pain in the same way as CLS. However, LESS improves cosmesis by leaving a single small scar.
    Compared with CLS, LESS did not reduce the incidence of complications or shorten postoperative hospital stay. Nor did it increase surgical time or the amount of bleeding during surgery. LESS can remove lymph nodes and ease postoperative pain in the same way as CLS. However, LESS improves cosmesis by leaving a single small scar.
    Papillary renal cell carcinoma (PRCC) is the second most common type of renal carcinoma following clear cell renal cell carcinoma, and the role of immune-related genes (IRGs) in tumorigenesis and metastasis is evident; its prognostic value in PRCC remains unclear. In this study, we downloaded the gene expression profiles and clinical data of patients with PRCC from The Cancer Genome Atlas (TCGA) database and obtained IRGs from the ImmPort database. A total of 371 differentially expressed IRGs (DEIRGs) were discovered between PRCC and normal kidney tissues. Prognostic DEIRGs (PDEIRGs) were identified by univariate Cox regression analysis. Then, we screened the four most representative PDEIRGs (IL13RA2, CCL19, BIRC5, and INHBE) and used them to construct a risk model to predict the prognosis of patients with PRCC. This model precisely stratified survival outcome and accurately identified mutation burden in PRCC. Thus, our results suggest that these four PDEIRGs are available prognostic predictors for PRCC. ThCC. Thus, our results suggest that these four PDEIRGs are available prognostic predictors for PRCC. They could be used to assess the prognosis and to guide individualized treatments for patients with PRCC.
    To evaluate the diagnostic value of dual-phase cone beam CT during hepatic arteriography (CBCTHA) for hepatocellular carcinoma (HCC).Thirty seven patients with unresectable HCC underwent the dual-phase CBCTHA prior to transarterial chemoembolization (TACE). Three blinded observers independently reviewed and compared the first phase CBCTHA images alone and the dual phase CBCTHA images. Diagnostic accuracy was evaluated by the alternative free-response receiver operating characteristic method (Area under the curve Az value). Sensitivities were analyzed with the paired t test. https://www.selleckchem.com/products/sh-4-54.html The analysis was performed for overall HCCs, HCCs up to 1 cm and those larger than 1 cm.For all HCCs and HCCs up to 1 cm, Az value and sensitivity showed no significant difference between the first-phase CBCTHA alone and the dual-phase CBCTHA (Az 0.81 vs 0.88, P = .07, 0.79 and 0.85, P = .14, sensitivity 0.61 and 0.73, P = .11, 0.41 and 0.52, P = .33, respectively). For HCCs larger than 1 cm, the mean Az value and sensitivity for the duaensitivity showed no significant difference between the first-phase CBCTHA alone and the dual-phase CBCTHA (Az 0.81 vs 0.88, P = .07, 0.79 and 0.85, P = .14, sensitivity 0.61 and 0.73, P = .11, 0.41 and 0.52, P = .33, respectively). For HCCs larger than 1 cm, the mean Az value and sensitivity for the dual-phase CBCTHA were significantly higher than those for the first phase CBCTHA alone (Az 0.96 vs 0.92, P = .008, sensitivity 0.85 vs 0.75, P = .013, respectively).The diagnostic accuracy of the dual-phase CBCTHA was superior to that of the first phase CBCTHA alone in the diagnosis of HCC larger than 1 cm.
    Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent chronic liver disease characterized by excess accumulation of fat in hepatocytes. Because no drug has been approved for NAFLD treatment, this work analyzed the effects of agents resulting from 2 research hotspots, metabolic target agents, and natural plant drugs, on NAFLD with network meta-analysis.

    Public databases were searched through August 14, 2020. Randomized controlled trials that compared obeticholic acid, elafibranor, cenicriviroc, selonsertib, curcumin, silymarin, and resveratrol to placebo were included. Liver pathology improvement, hepatic biochemical indicators, and lipid metabolism indicators were analyzed.

    Thirty-five studies were included in the meta-analysis. Obeticholic acid was found to significantly increase the frequency of liver biopsy improvement compared to placebo (OR 2.10; 95% CI 1.60, 2.77). The ranking results among the hepatic biochemical indicators showed that obeticholic acid (94.9%) and elafibranor (86.3%) have a relative advantage in reducing alanine aminotransferase (ALT) levels, and obeticholic acid also had an advantage (95.
    The retrieval time is of the establishment of the database to January 31, 2021. Two evaluators screens, extract and evaluate the literature, and the data are analyzed by RevMan5.3 software. The purpose of this study is to evaluate the effect of continuous nursing on the quality of life of hemodialysis patients by the MOS item short from health survey, exercise of self-care agency, and the incidence of complications. This study will provide reliable evidence for the application of continuous nursing in hemodialysis patients. DOI 10.17605/OSF.IO/HZKUA. DOI 10.17605/OSF.IO/HZKUA. To systematically review and evaluate the safety, advantages and clinical application value of laparo-endoscopic single-site surgery (LESS) for endometrial cancer by comparing it with conventional laparoscopic surgery (CLS). We conducted a systematic review of the published literature comparing LESS with CLS in the treatment of endometrial cancer. English databases including PubMed, Embase, Ovid, and the Cochrane Library and Chinese databases including Chinese National Knowledge Infrastructure, Wanfang and China Biology Medicine were searched for eligible observational studies up to July 10, 2019. We then evaluated the quality of the selected comparative studies before performing a meta-analysis using the RevMan 5.3 software. The complications, surgical time, blood loss during surgery, postoperative length of hospital stay and number of lymph nodes removed during surgery were compared between the 2 surgical approaches. Four studies with 234 patients were finally included in this meta-analysis. We found 53, 95% CI (-3.22 to 2.16), P = .70, I2 = 83%)]. However, patients treated with LESS had more pelvic lymph nodes removed during surgery than those treated with CLS (MD 3.33, 95% CI 1.05-5.62, P = .004, I2 = 32%). Compared with CLS, LESS did not reduce the incidence of complications or shorten postoperative hospital stay. Nor did it increase surgical time or the amount of bleeding during surgery. LESS can remove lymph nodes and ease postoperative pain in the same way as CLS. However, LESS improves cosmesis by leaving a single small scar. Compared with CLS, LESS did not reduce the incidence of complications or shorten postoperative hospital stay. Nor did it increase surgical time or the amount of bleeding during surgery. LESS can remove lymph nodes and ease postoperative pain in the same way as CLS. However, LESS improves cosmesis by leaving a single small scar. Papillary renal cell carcinoma (PRCC) is the second most common type of renal carcinoma following clear cell renal cell carcinoma, and the role of immune-related genes (IRGs) in tumorigenesis and metastasis is evident; its prognostic value in PRCC remains unclear. In this study, we downloaded the gene expression profiles and clinical data of patients with PRCC from The Cancer Genome Atlas (TCGA) database and obtained IRGs from the ImmPort database. A total of 371 differentially expressed IRGs (DEIRGs) were discovered between PRCC and normal kidney tissues. Prognostic DEIRGs (PDEIRGs) were identified by univariate Cox regression analysis. Then, we screened the four most representative PDEIRGs (IL13RA2, CCL19, BIRC5, and INHBE) and used them to construct a risk model to predict the prognosis of patients with PRCC. This model precisely stratified survival outcome and accurately identified mutation burden in PRCC. Thus, our results suggest that these four PDEIRGs are available prognostic predictors for PRCC. ThCC. Thus, our results suggest that these four PDEIRGs are available prognostic predictors for PRCC. They could be used to assess the prognosis and to guide individualized treatments for patients with PRCC. To evaluate the diagnostic value of dual-phase cone beam CT during hepatic arteriography (CBCTHA) for hepatocellular carcinoma (HCC).Thirty seven patients with unresectable HCC underwent the dual-phase CBCTHA prior to transarterial chemoembolization (TACE). Three blinded observers independently reviewed and compared the first phase CBCTHA images alone and the dual phase CBCTHA images. Diagnostic accuracy was evaluated by the alternative free-response receiver operating characteristic method (Area under the curve Az value). Sensitivities were analyzed with the paired t test. https://www.selleckchem.com/products/sh-4-54.html The analysis was performed for overall HCCs, HCCs up to 1 cm and those larger than 1 cm.For all HCCs and HCCs up to 1 cm, Az value and sensitivity showed no significant difference between the first-phase CBCTHA alone and the dual-phase CBCTHA (Az 0.81 vs 0.88, P = .07, 0.79 and 0.85, P = .14, sensitivity 0.61 and 0.73, P = .11, 0.41 and 0.52, P = .33, respectively). For HCCs larger than 1 cm, the mean Az value and sensitivity for the duaensitivity showed no significant difference between the first-phase CBCTHA alone and the dual-phase CBCTHA (Az 0.81 vs 0.88, P = .07, 0.79 and 0.85, P = .14, sensitivity 0.61 and 0.73, P = .11, 0.41 and 0.52, P = .33, respectively). For HCCs larger than 1 cm, the mean Az value and sensitivity for the dual-phase CBCTHA were significantly higher than those for the first phase CBCTHA alone (Az 0.96 vs 0.92, P = .008, sensitivity 0.85 vs 0.75, P = .013, respectively).The diagnostic accuracy of the dual-phase CBCTHA was superior to that of the first phase CBCTHA alone in the diagnosis of HCC larger than 1 cm. Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent chronic liver disease characterized by excess accumulation of fat in hepatocytes. Because no drug has been approved for NAFLD treatment, this work analyzed the effects of agents resulting from 2 research hotspots, metabolic target agents, and natural plant drugs, on NAFLD with network meta-analysis. Public databases were searched through August 14, 2020. Randomized controlled trials that compared obeticholic acid, elafibranor, cenicriviroc, selonsertib, curcumin, silymarin, and resveratrol to placebo were included. Liver pathology improvement, hepatic biochemical indicators, and lipid metabolism indicators were analyzed. Thirty-five studies were included in the meta-analysis. Obeticholic acid was found to significantly increase the frequency of liver biopsy improvement compared to placebo (OR 2.10; 95% CI 1.60, 2.77). The ranking results among the hepatic biochemical indicators showed that obeticholic acid (94.9%) and elafibranor (86.3%) have a relative advantage in reducing alanine aminotransferase (ALT) levels, and obeticholic acid also had an advantage (95.
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  • Similar results were found after the inverse probability of treatment weighting and propensity score-matching analyses. Regarding treatment-related adverse events, the HAIC-maintain group showed worse profiles in terms of leukopenia (all grades [p = 0.001] and grades 3 or 4 [p = 0.041]) and hypoalbuminemia (p = 0.001) than the Sorafenib-maintain group.

    The overall clinical efficacies between the sequential treatment of HAIC vs. sorafenib after LD-CCRT were comparable for locally advanced HCC.
    The overall clinical efficacies between the sequential treatment of HAIC vs. sorafenib after LD-CCRT were comparable for locally advanced HCC.Using an ultrasonication-assisted liquid exfoliation method, we have synthesized PtS2 nanosheets with good reproducibility. Herein, intrinsic peroxidase-like activity was for the first time demonstrated for PtS2 nanosheets, which can catalyze H2O2 oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to generate a colored solution. The catalytic mechanism of PtS2 nanosheets was investigated, which indicated that acceleration of the electron transfer between TMB and H2O2 was the main reason for the peroxidase-like activity of PtS2 nanosheets. Based on these observations, we exploited PtS2 nanosheets integrated into dopamine-functionalized hyaluronic acid (HA-DA) hydrogel microspheres by droplet microfluidics to construct PtS2 nanosheet- and PtS2@HA-DA microsphere-based sensors for highly sensitive determination of H2O2. When coupled with glucose oxidase, we further developed two glucose sensors based on the above two methods. Among them, the linearity of the PtS2 nanosheet-based spectrophotometry was in the range of 0.5 to 150 μM and the limit of detection as low as 0.20 μM. The linearity of the microsphere-based colorimetry was in the range 200 to 12,000 μM with a detection limit of 29.95 μM. Both of the glucose sensors can be applied to the determination of glucose in human serum with reliable results and reproducibility.Urchin-like peroxidase mimics 5,10,15,20-tetrakis (4-carboxyl phenyl) porphyrin-functionalized CuCo2O4 nanospheres (Por-CuCo2O4) has been fabricated as an excellent visual biosensor. X-ray diffractometry (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) have been employed to characterize the composition, morphologies, and elemental analysis of the as-synthesized Por-CuCo2O4. The catalytic activity of Por-CuCo2O4 was evaluated by the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) with the aid of H2O2, which exhibited a visual blue change with an absorption maximum at 652 nm for only 10 s. The peroxidase-like behaviors of Por-CuCo2O4 conformed to the Michaelis-Menten equation. Electrochemistry, radical scavenger, and fluorescence probe experiments verified that electron transfer, •O2- radicals, and holes (h+) are the important factors during the catalytic oxidation of TMB. Based on the inhibition of dopamine (DA) on TMB oxidation, the Por-CuCo2O4-based colorimetric biosensor has been successfully constructed for sensitive determination of DA witha detection limit (LOD) of 0.94 μΜ. In addition, colorimetry was validated to detect DA in serum samples with high sensitivity and good selectivity. 5,10,15,20-tetrakis (4-carboxyl phenyl) porphyrin-functionalized urchin-like CuCo2O4 (Por-CuCo2O4) with excellent peroxidase activity, ascribed to the synergistic effect between •O2- radicals and holes (h+). A fast colorimetric sensor on the basis of Por-CuCo2O4 has been constructed to quantitatively determine dopamine concentration in human serums.
    This study aims to compare the safety and effectiveness between transarterial chemoembolization (TACE) with drug-eluting beads (DEB-TACE) and conventional TACE (cTACE) using lipiodol-based regimens in HCC patients with a transjugular intrahepatic portosystemic shunt (TIPS).

    This retrospective study included patients with patent TIPS who underwent TACE from January 2013 to January 2019 that received either DEB-TACE (DEB-TACE group, n = 57) or cTACE (cTACE group, n = 62). https://www.selleckchem.com/products/Elesclomol.html The complications, liver toxicity, overall survival (OS), time to progression (TTP), and objective response rate (ORR) were compared between the groups.

    Altogether, 119 patients (50 ± 11 years, 107 men) were evaluated. The incidence of adverse events, including abdominal pain within 7 days (45.6% vs 79.0%, p < 0.001) and hepatic failure within 30 days (5.3% vs 19.4%, p = 0.027), were significantly lower in the DEB-TACE group than in the cTACE group. Compared to the cTACE group, the DEB-TACE group also showed mild liver toxicities in tffective in HCC patients after a TIPS procedure. • DEB-TACE improves overall survival, objective response rate, and liver toxicities and is non-inferior to cTACE in terms of time to progression. • DEB-TACE might be a potential new therapeutic option for HCC patients with TIPS.
    To investigate the image quality and perception of a sinogram-based deep learningimage reconstruction (DLIR) algorithm for single-energy abdominal CT compared to standard-of-care strength of ASIR-V.

    In this retrospective study, 50 patients (62% F; 56.74 ± 17.05 years) underwent portal venous phase. Four reconstructions (ASIR-V at 40%, and DLIR at three strengths low (DLIR-L), medium (DLIR-M), and high (DLIR-H)) were generated. Qualitative and quantitative image quality analysis was performed on the 200 image datasets. Qualitative scores were obtained for image noise, contrast, small structure visibility, sharpness, and artifact by three blinded radiologists on a 5-point scale (1, excellent; 5, very poor). Radiologists also indicated image preference on a 3-point scale (1, most preferred; 3, least preferred). Quantitative assessment was performed by measuring image noise and contrast-to-noise ratio (CNR).

    DLIR had better image quality scores compared to ASIR-V. Scores on DLIR-H for noise (1.40 ± 0.53), ctruction techniques. • DLIR may be advantageous in patients with large body habitus due to a lower image noise. • DLIR can enable further optimization of radiation doses used in abdominal CT.
    • Deep learning image reconstructions (DLIRs) have a higher contrast-to-noise ratio compared to medium-strength hybrid iterative reconstruction techniques. • DLIR may be advantageous in patients with large body habitus due to a lower image noise. • DLIR can enable further optimization of radiation doses used in abdominal CT.
    Similar results were found after the inverse probability of treatment weighting and propensity score-matching analyses. Regarding treatment-related adverse events, the HAIC-maintain group showed worse profiles in terms of leukopenia (all grades [p = 0.001] and grades 3 or 4 [p = 0.041]) and hypoalbuminemia (p = 0.001) than the Sorafenib-maintain group. The overall clinical efficacies between the sequential treatment of HAIC vs. sorafenib after LD-CCRT were comparable for locally advanced HCC. The overall clinical efficacies between the sequential treatment of HAIC vs. sorafenib after LD-CCRT were comparable for locally advanced HCC.Using an ultrasonication-assisted liquid exfoliation method, we have synthesized PtS2 nanosheets with good reproducibility. Herein, intrinsic peroxidase-like activity was for the first time demonstrated for PtS2 nanosheets, which can catalyze H2O2 oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to generate a colored solution. The catalytic mechanism of PtS2 nanosheets was investigated, which indicated that acceleration of the electron transfer between TMB and H2O2 was the main reason for the peroxidase-like activity of PtS2 nanosheets. Based on these observations, we exploited PtS2 nanosheets integrated into dopamine-functionalized hyaluronic acid (HA-DA) hydrogel microspheres by droplet microfluidics to construct PtS2 nanosheet- and PtS2@HA-DA microsphere-based sensors for highly sensitive determination of H2O2. When coupled with glucose oxidase, we further developed two glucose sensors based on the above two methods. Among them, the linearity of the PtS2 nanosheet-based spectrophotometry was in the range of 0.5 to 150 μM and the limit of detection as low as 0.20 μM. The linearity of the microsphere-based colorimetry was in the range 200 to 12,000 μM with a detection limit of 29.95 μM. Both of the glucose sensors can be applied to the determination of glucose in human serum with reliable results and reproducibility.Urchin-like peroxidase mimics 5,10,15,20-tetrakis (4-carboxyl phenyl) porphyrin-functionalized CuCo2O4 nanospheres (Por-CuCo2O4) has been fabricated as an excellent visual biosensor. X-ray diffractometry (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) have been employed to characterize the composition, morphologies, and elemental analysis of the as-synthesized Por-CuCo2O4. The catalytic activity of Por-CuCo2O4 was evaluated by the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) with the aid of H2O2, which exhibited a visual blue change with an absorption maximum at 652 nm for only 10 s. The peroxidase-like behaviors of Por-CuCo2O4 conformed to the Michaelis-Menten equation. Electrochemistry, radical scavenger, and fluorescence probe experiments verified that electron transfer, •O2- radicals, and holes (h+) are the important factors during the catalytic oxidation of TMB. Based on the inhibition of dopamine (DA) on TMB oxidation, the Por-CuCo2O4-based colorimetric biosensor has been successfully constructed for sensitive determination of DA witha detection limit (LOD) of 0.94 μΜ. In addition, colorimetry was validated to detect DA in serum samples with high sensitivity and good selectivity. 5,10,15,20-tetrakis (4-carboxyl phenyl) porphyrin-functionalized urchin-like CuCo2O4 (Por-CuCo2O4) with excellent peroxidase activity, ascribed to the synergistic effect between •O2- radicals and holes (h+). A fast colorimetric sensor on the basis of Por-CuCo2O4 has been constructed to quantitatively determine dopamine concentration in human serums. This study aims to compare the safety and effectiveness between transarterial chemoembolization (TACE) with drug-eluting beads (DEB-TACE) and conventional TACE (cTACE) using lipiodol-based regimens in HCC patients with a transjugular intrahepatic portosystemic shunt (TIPS). This retrospective study included patients with patent TIPS who underwent TACE from January 2013 to January 2019 that received either DEB-TACE (DEB-TACE group, n = 57) or cTACE (cTACE group, n = 62). https://www.selleckchem.com/products/Elesclomol.html The complications, liver toxicity, overall survival (OS), time to progression (TTP), and objective response rate (ORR) were compared between the groups. Altogether, 119 patients (50 ± 11 years, 107 men) were evaluated. The incidence of adverse events, including abdominal pain within 7 days (45.6% vs 79.0%, p < 0.001) and hepatic failure within 30 days (5.3% vs 19.4%, p = 0.027), were significantly lower in the DEB-TACE group than in the cTACE group. Compared to the cTACE group, the DEB-TACE group also showed mild liver toxicities in tffective in HCC patients after a TIPS procedure. • DEB-TACE improves overall survival, objective response rate, and liver toxicities and is non-inferior to cTACE in terms of time to progression. • DEB-TACE might be a potential new therapeutic option for HCC patients with TIPS. To investigate the image quality and perception of a sinogram-based deep learningimage reconstruction (DLIR) algorithm for single-energy abdominal CT compared to standard-of-care strength of ASIR-V. In this retrospective study, 50 patients (62% F; 56.74 ± 17.05 years) underwent portal venous phase. Four reconstructions (ASIR-V at 40%, and DLIR at three strengths low (DLIR-L), medium (DLIR-M), and high (DLIR-H)) were generated. Qualitative and quantitative image quality analysis was performed on the 200 image datasets. Qualitative scores were obtained for image noise, contrast, small structure visibility, sharpness, and artifact by three blinded radiologists on a 5-point scale (1, excellent; 5, very poor). Radiologists also indicated image preference on a 3-point scale (1, most preferred; 3, least preferred). Quantitative assessment was performed by measuring image noise and contrast-to-noise ratio (CNR). DLIR had better image quality scores compared to ASIR-V. Scores on DLIR-H for noise (1.40 ± 0.53), ctruction techniques. • DLIR may be advantageous in patients with large body habitus due to a lower image noise. • DLIR can enable further optimization of radiation doses used in abdominal CT. • Deep learning image reconstructions (DLIRs) have a higher contrast-to-noise ratio compared to medium-strength hybrid iterative reconstruction techniques. • DLIR may be advantageous in patients with large body habitus due to a lower image noise. • DLIR can enable further optimization of radiation doses used in abdominal CT.
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  • Overall, 48% (range 31-64%) and 64% (range 39-89%) agreed on a need to change their unit's caesarean and induction practices respectively. The three units where greatest need for change was perceived also had least readiness for change in terms of leadership, culture, and resources. Regarding inter-disciplinary variation, medical staff were more likely than midwifery staff to believe women were appropriately informed and less likely to believe unit practice change was required.

    Planned birth practices and change readiness varied between participating hospitals and professional groups. Hospitals with greatest perceived need for change perceived least resources to implement such change.
    Planned birth practices and change readiness varied between participating hospitals and professional groups. Hospitals with greatest perceived need for change perceived least resources to implement such change.
    While the association between occupational inhalation of silica dust and pulmonary tuberculosis has been known for over a century, there has never been a published systematic review, particularly of experience in the current era of less severe silicosis and treatable tuberculosis. We undertook a systematic review of the evidence for the association between (1) silicosis and pulmonary tuberculosis, and (2) silica exposure and pulmonary tuberculosis controlling for silicosis, and their respective exposure-response gradients.

    We searched PUBMED and EMBASE, and selected studies according to a priori inclusion criteria. We extracted, summarised and pooled the results of published case-control and cohort studies of silica exposure and/or silicosis and incident active tuberculosis. Study quality was assessed on the Newcastle-Ottawa Scale. Where meta-analysis was possible, effect estimates were pooled using inverse-variance weighted random-effects models. Otherwise narrative and graphic synthesis was undertaken. ica exposure without radiological silicosis. Research is needed, particularly cohort studies measuring silica exposure in different settings, to characterise the effect more accurately as well as the silica exposure threshold that could be used to prevent excess tuberculosis risk.
    The evidence is robust for a strongly elevated risk of tuberculosis with radiological silicosis, with a low disease severity threshold. The effect estimate is more uncertain for silica exposure without radiological silicosis. Research is needed, particularly cohort studies measuring silica exposure in different settings, to characterise the effect more accurately as well as the silica exposure threshold that could be used to prevent excess tuberculosis risk.
    While rates of e-cigarette use ('vaping') continue to potentiate concern, there is limited data on common symptoms of e-cigarette dependence among young adults who vape. This study sought to critically explore how young adults experience, manifest, and conceptualize vaping dependence symptoms in their everyday lives.

    Between June 2018 and 2019, in-depth qualitative interviews were conducted with 62 young adults who use e-cigarettes (aged 18-25) and live in Southern California. We explored participants' product preferences, daily e-cigarette use patterns, vaping history, withdrawal experiences, and quit attempts or periods of cessation. We used a thematic analysis approach to interpret the transcripts.

    Young adults discussed nine dimensions of vaping dependence that were organized into two categories 1) general nicotine dependence symptoms, and 2) unique dependence symptoms related to vaping. Nicotine dependence symptoms included cravings and urgency to use, increased use to achieve desired effects, and onsidered in discussions of policies as well as treatment and education efforts intended to protect young people from e-cigarette dependence.
    In the last decade surgical care has been propelled into the public health domain with the establishment of a World Health Organisation (WHO) designated programme and key publications. The passing of the historic World Health Assembly Resolution (WHA) acknowledged surgical care as a vital component towards achieving Universal Health Coverage (UHC). We conducted the first worldwide survey to explore the perception of surgical care as a public health issue.

    The anonymous, cross sectional survey targeted worldwide participants across a range of professional backgrounds, including non-medical using virtual snowball sampling method (in English) using Google Forms (Google Inc., Mountain View, CA, USA) from 20th February 2019 to 25th June 2019. The survey questions were designed to gauge awareness on Sustainable Development Goals (SDGs), UHC, WHO programmes and key publications on surgical care as well as perception of surgical care as a priority topic in public health.

    The survey was completed by 1954 respondublic health issue amongst our respondents. Surgical care was not seen as a priority to reach the SDGs, less visible as a WHO programme and not perceived as an important topic for public health courses.
    Preterm delivery is the birth of a baby before 37 weeks of gestation. This global phenomenon is a critical issue of concern especially in developing countries that are resource-constrained when it comes to the management of preterm babies. Complications associated with prematurity contribute significantly to under-five mortality and are linked with feelings of despair, grief, and anxiety among mothers.

    This was a qualitative descriptive study in an urban setting in the Greater Accra region of Ghana. Eleven mothers whose babies had been discharged from the neonatal intensive care unit in a major hospital and resided in Accra were interviewed in their homes using a semi-structured interview guide. Data were audiotaped, transcribed verbatim, and analyzed inductively by content analysis.

    All the mothers had formal education and the mean maternal age was 27.9 years. https://www.selleckchem.com/products/jnk-inhibitor-viii.html The majority of the mothers were multiparous. The gestational age at birth ranged from 32 to 34 weeks and the average birth weight of their babies was 1.61kg. Four major themes emerged which included Around the clock care; mothers' self-perceptions and attitudes of significant others; mothers' health and wellbeing; and support. Most of the mothers experienced physical exhaustion from the extra demands involved with care, had negative emotions, and unmet social needs.

    The findings indicate that home management of preterm babies poses multiple stressors and is associated with poor psychological and physical wellbeing among mothers. Hence, the need for extensive education and identification of other social support systems to augment facility-based care for mothers and their pretermbabies.
    The findings indicate that home management of preterm babies poses multiple stressors and is associated with poor psychological and physical wellbeing among mothers. Hence, the need for extensive education and identification of other social support systems to augment facility-based care for mothers and their preterm babies.
    Overall, 48% (range 31-64%) and 64% (range 39-89%) agreed on a need to change their unit's caesarean and induction practices respectively. The three units where greatest need for change was perceived also had least readiness for change in terms of leadership, culture, and resources. Regarding inter-disciplinary variation, medical staff were more likely than midwifery staff to believe women were appropriately informed and less likely to believe unit practice change was required. Planned birth practices and change readiness varied between participating hospitals and professional groups. Hospitals with greatest perceived need for change perceived least resources to implement such change. Planned birth practices and change readiness varied between participating hospitals and professional groups. Hospitals with greatest perceived need for change perceived least resources to implement such change. While the association between occupational inhalation of silica dust and pulmonary tuberculosis has been known for over a century, there has never been a published systematic review, particularly of experience in the current era of less severe silicosis and treatable tuberculosis. We undertook a systematic review of the evidence for the association between (1) silicosis and pulmonary tuberculosis, and (2) silica exposure and pulmonary tuberculosis controlling for silicosis, and their respective exposure-response gradients. We searched PUBMED and EMBASE, and selected studies according to a priori inclusion criteria. We extracted, summarised and pooled the results of published case-control and cohort studies of silica exposure and/or silicosis and incident active tuberculosis. Study quality was assessed on the Newcastle-Ottawa Scale. Where meta-analysis was possible, effect estimates were pooled using inverse-variance weighted random-effects models. Otherwise narrative and graphic synthesis was undertaken. ica exposure without radiological silicosis. Research is needed, particularly cohort studies measuring silica exposure in different settings, to characterise the effect more accurately as well as the silica exposure threshold that could be used to prevent excess tuberculosis risk. The evidence is robust for a strongly elevated risk of tuberculosis with radiological silicosis, with a low disease severity threshold. The effect estimate is more uncertain for silica exposure without radiological silicosis. Research is needed, particularly cohort studies measuring silica exposure in different settings, to characterise the effect more accurately as well as the silica exposure threshold that could be used to prevent excess tuberculosis risk. While rates of e-cigarette use ('vaping') continue to potentiate concern, there is limited data on common symptoms of e-cigarette dependence among young adults who vape. This study sought to critically explore how young adults experience, manifest, and conceptualize vaping dependence symptoms in their everyday lives. Between June 2018 and 2019, in-depth qualitative interviews were conducted with 62 young adults who use e-cigarettes (aged 18-25) and live in Southern California. We explored participants' product preferences, daily e-cigarette use patterns, vaping history, withdrawal experiences, and quit attempts or periods of cessation. We used a thematic analysis approach to interpret the transcripts. Young adults discussed nine dimensions of vaping dependence that were organized into two categories 1) general nicotine dependence symptoms, and 2) unique dependence symptoms related to vaping. Nicotine dependence symptoms included cravings and urgency to use, increased use to achieve desired effects, and onsidered in discussions of policies as well as treatment and education efforts intended to protect young people from e-cigarette dependence. In the last decade surgical care has been propelled into the public health domain with the establishment of a World Health Organisation (WHO) designated programme and key publications. The passing of the historic World Health Assembly Resolution (WHA) acknowledged surgical care as a vital component towards achieving Universal Health Coverage (UHC). We conducted the first worldwide survey to explore the perception of surgical care as a public health issue. The anonymous, cross sectional survey targeted worldwide participants across a range of professional backgrounds, including non-medical using virtual snowball sampling method (in English) using Google Forms (Google Inc., Mountain View, CA, USA) from 20th February 2019 to 25th June 2019. The survey questions were designed to gauge awareness on Sustainable Development Goals (SDGs), UHC, WHO programmes and key publications on surgical care as well as perception of surgical care as a priority topic in public health. The survey was completed by 1954 respondublic health issue amongst our respondents. Surgical care was not seen as a priority to reach the SDGs, less visible as a WHO programme and not perceived as an important topic for public health courses. Preterm delivery is the birth of a baby before 37 weeks of gestation. This global phenomenon is a critical issue of concern especially in developing countries that are resource-constrained when it comes to the management of preterm babies. Complications associated with prematurity contribute significantly to under-five mortality and are linked with feelings of despair, grief, and anxiety among mothers. This was a qualitative descriptive study in an urban setting in the Greater Accra region of Ghana. Eleven mothers whose babies had been discharged from the neonatal intensive care unit in a major hospital and resided in Accra were interviewed in their homes using a semi-structured interview guide. Data were audiotaped, transcribed verbatim, and analyzed inductively by content analysis. All the mothers had formal education and the mean maternal age was 27.9 years. https://www.selleckchem.com/products/jnk-inhibitor-viii.html The majority of the mothers were multiparous. The gestational age at birth ranged from 32 to 34 weeks and the average birth weight of their babies was 1.61kg. Four major themes emerged which included Around the clock care; mothers' self-perceptions and attitudes of significant others; mothers' health and wellbeing; and support. Most of the mothers experienced physical exhaustion from the extra demands involved with care, had negative emotions, and unmet social needs. The findings indicate that home management of preterm babies poses multiple stressors and is associated with poor psychological and physical wellbeing among mothers. Hence, the need for extensive education and identification of other social support systems to augment facility-based care for mothers and their pretermbabies. The findings indicate that home management of preterm babies poses multiple stressors and is associated with poor psychological and physical wellbeing among mothers. Hence, the need for extensive education and identification of other social support systems to augment facility-based care for mothers and their preterm babies.
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  • Brunner's gland hyperplasia is a rare, benign lesion of the duodenum. The symptomology can range from asymptomatic (as an incidental finding on endoscopy) to gastrointestinal obstruction or haemorrhage.

    We report a case of a 60-year-old man presenting with post-prandial vomiting and weight loss. Inpatient evaluation led to the likely diagnosis of a duodenal malignancy for which the patient underwent a laparotomy and proximal duodenectomy.

    Brunner's gland hyperplasia is a rare, benign condition that can be overtreated due to the difficulty in obtaining an accurate pre-operative diagnosis. The literature has been reviewed to discuss the approach to diagnosis.

    This case highlights the potential for Brunner's gland hyperplasia mimicking a malignancy.
    This case highlights the potential for Brunner's gland hyperplasia mimicking a malignancy.
    Swan neck deformity (SND) is characterized by hyperextension of proximal interphalangeal (PIP) joint and extension lag of distal interphalangeal (DIP) joint with functional loss of finger and impairs of tight grip of the finger. SND often results from chronic mallet injury and requires surgical treatment. One of the procedure is spiral oblique retinaculum ligament (SORL) reconstruction. We reported good outcome of swan neck deformity due to chronic mallet finger cases treated with SORL reconstruction using lateral band technique.

    We presented 2 case of swan neck deformity due to chronic mallet finger. A 21-year-old male with deformity of the left index finger for 2 years with with extension lag 50° and -20° PIP joint hyperextension and A 18-year-female with deformity of right ring finger for 4 years with extension lag 40° and -20° PIP joint hyperextension. We performed SORL reconstruction using lateral band technique. Ten weeks after surgery, patient achieved good range of motion and stability of PIP and DIP joint was obtained.

    SORL reconstruction in a finger with a chronic mallet deformity coordinates extension of PIP and DIP joints by a dynamic tenodesis effect. This concept improves stability of both DIP and PIP joints by linking the volar flexor sheath to the lateral aspect of the terminal tendon using lateral band, thereby providing a mechanism of for automatic DIP joint extension upon active PIP extension.

    SORL reconstruction using lateral band technique may be a good choice for treating swan neck deformity.
    SORL reconstruction using lateral band technique may be a good choice for treating swan neck deformity.
    This is the first case of idiopathic giant pancreatic pseudocyst (IGPP) causing intestinal occlusion, intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) reported in the literature. Diagnosis of IGPP in emergency is a challenge because of its rarity and the absence of a history of pancreatitis or pancreatic trauma and specific clinical presentation. Abdominal contrast-enhanced computed tomography (CECT) represents the gold standard in diagnosing of pancreatic cyst (PP). Different types of treatment of PP are reported in the literature.

    A 52-year-old Caucasian female was admitted to the Emergency Department with a three-day history of abdominal pain, inability to pass gas or stool, nausea and vomiting, oliguria and a seven-day history of abdominal swelling and swollen legs. Physical examination revealed abdominal distention, abdominal pain, swelling in the legs. CECT showed a voluminous cystic pancreatic mass suspected of neoplasm. Laboratory tests reported high serum levels of BUN, creatinine and C-reactive protein and neutrophilic leukocytosis. After preoperative diagnosis of ACS, the patient was taken to the operating room for pancreatic resection. The postoperative course was uneventful. Diagnosis of IGPP was made by histopathological examination.

    IGPP is difficult to diagnose in emergency. Although different types of drainage of IGPP are described in the literature, pancreatic resection represents the treatment of choice when a cystic pancreatic neoplasm cannot be excluded.

    IGPP is a rare disease that may cause intestinal occlusion, IAH and ACS. Pancreatic resection if necessary is safe and therapeutic with acceptable morbidity and mortality.
    IGPP is a rare disease that may cause intestinal occlusion, IAH and ACS. https://www.selleckchem.com/products/lyn-1604.html Pancreatic resection if necessary is safe and therapeutic with acceptable morbidity and mortality.
    Common Hepatic Artery (CHA) Pseudoaneurysm is a rare entity, attributed to infections, trauma, and upper abdominal surgery. Most cases occur after biliary and pancreatic surgery. CHA pseudoaneurysm after total gastrectomy is uncommon and can be devastating.

    A 58-years male who underwent D2 total gastrectomy for gastric carcinoma ten days ago, presented with hematemesis, epigastric pain, and a history of melaena. After admission, upper gastrointestinal endoscopy showed a clot at the jejunojejunostomy site. Computed tomography with angiography was diagnostic of pseudoaneurysm of CHA located inferiorly. Coil embolization of CHA was done and the patient improved.

    Pseudoaneurysm of the common hepatic artery is a serious complication after abdominal surgery. Only a few cases have been reported with similar symptoms related to gastrointestinal bleeding following various upper abdominal surgeries. Coil embolization is a gold standard technique with a high success rate.

    CHA pseudoaneurysm is a dreadful potential complication of abdominal surgery including gastrectomy. Early recognition and emergency management of CHA pseudoaneurysm are crucial for a favorable outcome for patients with bleeding from CHA aneurysm.
    CHA pseudoaneurysm is a dreadful potential complication of abdominal surgery including gastrectomy. Early recognition and emergency management of CHA pseudoaneurysm are crucial for a favorable outcome for patients with bleeding from CHA aneurysm.
    Thyroid metastasis of colorectal cancer is rare and the patient with thyroid metastasis has no symptoms early in the disease course. On the other hand, evaluation of thyroid is not generally included in the routine follow-up of colorectal cancer. Therefore, the diagnosis of thyroid metastasis of colorectal cancer may be delayed.

    Chest computed tomography revealed a nodule on the right lobe of the thyroid in 53-year-old woman diagnosed with sigmoid colon adenocarcinoma. This nodule was identified having as increased metabolic activity by
    F-fluorodeoxyglucose positron emission tomography-computed tomography and confirmed to be consisted of cystic and solid portions by ultrasonography. Fine needle aspiration cytology of the nodule revealed metastasis of colon cancer. The patient underwent laparoscopic anterior resection and a total thyroidectomy. The size of the thyroid tumor was 1.2 cm with free resection margin.

    The clinical features of thyroid metastasis from colorectal cancer are not typical. In addition, follow-up examinations of patients with colorectal cancer do not include imaging studies of the neck, so the diagnosis of thyroid metastases is delayed.
    Brunner's gland hyperplasia is a rare, benign lesion of the duodenum. The symptomology can range from asymptomatic (as an incidental finding on endoscopy) to gastrointestinal obstruction or haemorrhage. We report a case of a 60-year-old man presenting with post-prandial vomiting and weight loss. Inpatient evaluation led to the likely diagnosis of a duodenal malignancy for which the patient underwent a laparotomy and proximal duodenectomy. Brunner's gland hyperplasia is a rare, benign condition that can be overtreated due to the difficulty in obtaining an accurate pre-operative diagnosis. The literature has been reviewed to discuss the approach to diagnosis. This case highlights the potential for Brunner's gland hyperplasia mimicking a malignancy. This case highlights the potential for Brunner's gland hyperplasia mimicking a malignancy. Swan neck deformity (SND) is characterized by hyperextension of proximal interphalangeal (PIP) joint and extension lag of distal interphalangeal (DIP) joint with functional loss of finger and impairs of tight grip of the finger. SND often results from chronic mallet injury and requires surgical treatment. One of the procedure is spiral oblique retinaculum ligament (SORL) reconstruction. We reported good outcome of swan neck deformity due to chronic mallet finger cases treated with SORL reconstruction using lateral band technique. We presented 2 case of swan neck deformity due to chronic mallet finger. A 21-year-old male with deformity of the left index finger for 2 years with with extension lag 50° and -20° PIP joint hyperextension and A 18-year-female with deformity of right ring finger for 4 years with extension lag 40° and -20° PIP joint hyperextension. We performed SORL reconstruction using lateral band technique. Ten weeks after surgery, patient achieved good range of motion and stability of PIP and DIP joint was obtained. SORL reconstruction in a finger with a chronic mallet deformity coordinates extension of PIP and DIP joints by a dynamic tenodesis effect. This concept improves stability of both DIP and PIP joints by linking the volar flexor sheath to the lateral aspect of the terminal tendon using lateral band, thereby providing a mechanism of for automatic DIP joint extension upon active PIP extension. SORL reconstruction using lateral band technique may be a good choice for treating swan neck deformity. SORL reconstruction using lateral band technique may be a good choice for treating swan neck deformity. This is the first case of idiopathic giant pancreatic pseudocyst (IGPP) causing intestinal occlusion, intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) reported in the literature. Diagnosis of IGPP in emergency is a challenge because of its rarity and the absence of a history of pancreatitis or pancreatic trauma and specific clinical presentation. Abdominal contrast-enhanced computed tomography (CECT) represents the gold standard in diagnosing of pancreatic cyst (PP). Different types of treatment of PP are reported in the literature. A 52-year-old Caucasian female was admitted to the Emergency Department with a three-day history of abdominal pain, inability to pass gas or stool, nausea and vomiting, oliguria and a seven-day history of abdominal swelling and swollen legs. Physical examination revealed abdominal distention, abdominal pain, swelling in the legs. CECT showed a voluminous cystic pancreatic mass suspected of neoplasm. Laboratory tests reported high serum levels of BUN, creatinine and C-reactive protein and neutrophilic leukocytosis. After preoperative diagnosis of ACS, the patient was taken to the operating room for pancreatic resection. The postoperative course was uneventful. Diagnosis of IGPP was made by histopathological examination. IGPP is difficult to diagnose in emergency. Although different types of drainage of IGPP are described in the literature, pancreatic resection represents the treatment of choice when a cystic pancreatic neoplasm cannot be excluded. IGPP is a rare disease that may cause intestinal occlusion, IAH and ACS. Pancreatic resection if necessary is safe and therapeutic with acceptable morbidity and mortality. IGPP is a rare disease that may cause intestinal occlusion, IAH and ACS. https://www.selleckchem.com/products/lyn-1604.html Pancreatic resection if necessary is safe and therapeutic with acceptable morbidity and mortality. Common Hepatic Artery (CHA) Pseudoaneurysm is a rare entity, attributed to infections, trauma, and upper abdominal surgery. Most cases occur after biliary and pancreatic surgery. CHA pseudoaneurysm after total gastrectomy is uncommon and can be devastating. A 58-years male who underwent D2 total gastrectomy for gastric carcinoma ten days ago, presented with hematemesis, epigastric pain, and a history of melaena. After admission, upper gastrointestinal endoscopy showed a clot at the jejunojejunostomy site. Computed tomography with angiography was diagnostic of pseudoaneurysm of CHA located inferiorly. Coil embolization of CHA was done and the patient improved. Pseudoaneurysm of the common hepatic artery is a serious complication after abdominal surgery. Only a few cases have been reported with similar symptoms related to gastrointestinal bleeding following various upper abdominal surgeries. Coil embolization is a gold standard technique with a high success rate. CHA pseudoaneurysm is a dreadful potential complication of abdominal surgery including gastrectomy. Early recognition and emergency management of CHA pseudoaneurysm are crucial for a favorable outcome for patients with bleeding from CHA aneurysm. CHA pseudoaneurysm is a dreadful potential complication of abdominal surgery including gastrectomy. Early recognition and emergency management of CHA pseudoaneurysm are crucial for a favorable outcome for patients with bleeding from CHA aneurysm. Thyroid metastasis of colorectal cancer is rare and the patient with thyroid metastasis has no symptoms early in the disease course. On the other hand, evaluation of thyroid is not generally included in the routine follow-up of colorectal cancer. Therefore, the diagnosis of thyroid metastasis of colorectal cancer may be delayed. Chest computed tomography revealed a nodule on the right lobe of the thyroid in 53-year-old woman diagnosed with sigmoid colon adenocarcinoma. This nodule was identified having as increased metabolic activity by F-fluorodeoxyglucose positron emission tomography-computed tomography and confirmed to be consisted of cystic and solid portions by ultrasonography. Fine needle aspiration cytology of the nodule revealed metastasis of colon cancer. The patient underwent laparoscopic anterior resection and a total thyroidectomy. The size of the thyroid tumor was 1.2 cm with free resection margin. The clinical features of thyroid metastasis from colorectal cancer are not typical. In addition, follow-up examinations of patients with colorectal cancer do not include imaging studies of the neck, so the diagnosis of thyroid metastases is delayed.
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  • This study reveals that the proposed three-stage process, ultrasonication pretreatment-alkaline fermentation-supported liquid membrane, effectively produces stable sludge with reduced heavy metal toxicity and recovers metals from organic waste streams.New munition compounds have been developed to replace traditional explosives to prevent unintended detonations. However, insensitive munitions (IM) can leave large proportion of unexploded charge in the field, where it is subjected to photodegradation and dissolution in precipitation. The photolytic reactions occurring on the surfaces of IMX-101 and IMX-104 formulations and the subsequent fate of photolytic products in the environment were thoroughly investigated. The constituents of IMX-101 and IMX-104 formulations dissolve sequentially under rainfall in the order of aqueous solubility 3-nitro-1,2,4-triazol-5-one (NTO) > nitroguanidine (NQ) > 2,4-dinitroanisole (DNAN) > 1,3,5-hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). A linear relationship between DNAN dissolution and rainwater volume was observed (r2 0.86-0.99). It was estimated that it would take 16-228 years to completely dissolve these formulation particles under natural environmental conditions in Oracle, AZ. We used LC/MS/MS and GC/MS to examine the dissolution samples from IMX-101 and 104 particles exposed to rainfall and sunlight and found six DNAN photo-transformation products including 2-methoxy-5-nitrophenol, 4-methoxy-3-nitrophenol, 4-methoxy-3-nitroaniline, 2-methoxy-5-nitroaniline, 2,4-dinitrophenol, and methoxy-dinitrophenol, which are in good agreement with computational modeling results of bond strengths. The main DNAN photodegradation pathways are therefore proposed. Predicted eco-toxicity values suggested that the parent compound DNAN, methoxy-nitrophenols, methoxy-nitroanilines and the other two products (2,4-dinitrophenol and methoxy-dinitrophenol) would be harmful to fish and daphnid. Our study provides improved insight about the rain dissolution and photochemical behavior of IM formulations under natural conditions, which helps to form target-oriented strategies to mitigate explosive contamination in military training sites.A requirement of the Construction Products Regulation (CPR) in the European Union states that construction works must be designed in such a way that throughout their entire life cycle, they have no exceedingly high environmental impact. The objective of the current work was to simulate the leaching of selected metals and sulfate in vertical test panels (VTPs) covered by plaster and mortar. The investigation is based on 18-month leaching outdoor tests (LOT) under real weather conditions. A leaching model was developed using the geochemical model PHREEQC with the Lawrence Livermore National Laboratory (LLNL) thermodynamic data base and coupled with MATLAB in order to optimize the run-off and weather parameters. The model was calibrated by comparing the data from laboratory Dynamic Surface Leaching Tests (DSLT) with simulation results up to an acceptable fit. The parameters obtained were then used in the LOT simulations and validated. The model allows predictions on the substance discharge from various plasters and mortars under real weather conditions. Physical characteristics of the material (e.g., thickness and absorption capacity) play an important role in the leaching of substances in façades covered with plaster and mortar. https://www.selleckchem.com/products/xmd8-92.html The lower the thickness and absorption capacity of the material applied, the greater the run-off and discharge of leached substances.Currently, seawater desalination based on air-water interface solar heating has triggered significant research interests because it effectively makes use of the solar energy and avoids fossil fuel consumption. However, to prevent the volatile organic compounds (VOCs) from volatilizing with water vapor which later will liquefy and enter the condensed freshwater is still a challenge. In this work, a g-C3N4/MoS2 based floating solar still (CM-FSS) combined with thermal/light activation of persulfate (PS) at air-water interface was applied for clean freshwater production for the first time. The CM-FSS was composed of a g-C3N4/MoS2 top layer for solar absorption, simultaneous thermal/light activation of PS and then VOCs degradation at air-water interface, a floating layer of expandable polyethylene (EPE) foam for heat isolation, and a transport channel of air-laid paper (ALP) for seawater and PS solution delivery. The water evaporation rate of the CM-FSS was measured at 1.23 kg m-2 h-1 under 1 kW m-2, which is 4.09 times higher than that of pure water without an evaporator. With the assistance of g-C3N4/MoS2 photocatalytic degradation and thermal/light activation of PS at the air-water interface, a high removal efficiency of a selected model VOCs pollutant of nitrobenzene (NB) could reach to 98.2% in condensed freshwater. Finally, when real seawater samples were employed as source water for solar distillation, the typical water-quality indices such as salinity, turbidity, anions, cations and organics of the condensed freshwater were below the limit values of the Standards for Drinking Water Quality in WHO, US EPA and China.Brominated benzenes and phenols constitute direct precursors in the formation of bromine-bearing pollutants; most notably PBDD/Fs and other dioxin-type compounds. Elucidating accurate mechanisms and constructing robust kinetic models for the oxidative transformation of bromobenzenes and bromophenols into notorious Br-toxicants entail a comprehensive understanding of their initial oxidation steps. However, pertinent mechanistic studies, based on quantum chemical calculations, have only focused on secondary condensation reactions into PBDD/Fs and PBDEs. Literature provide kinetic parameters for these significant reactions, nonetheless, without attempting to compile the acquired Arrhenius coefficients into kinetic models. To fill in this gap, this study sets out to illustrate primary chemical phenomena underpinning the low-temperature combustion of a monobromobenzene molecule (MBZ) based on a detail chemical kinetic model. The main aim is to map out temperature-dependent profiles for major intermediates and products.
    This study reveals that the proposed three-stage process, ultrasonication pretreatment-alkaline fermentation-supported liquid membrane, effectively produces stable sludge with reduced heavy metal toxicity and recovers metals from organic waste streams.New munition compounds have been developed to replace traditional explosives to prevent unintended detonations. However, insensitive munitions (IM) can leave large proportion of unexploded charge in the field, where it is subjected to photodegradation and dissolution in precipitation. The photolytic reactions occurring on the surfaces of IMX-101 and IMX-104 formulations and the subsequent fate of photolytic products in the environment were thoroughly investigated. The constituents of IMX-101 and IMX-104 formulations dissolve sequentially under rainfall in the order of aqueous solubility 3-nitro-1,2,4-triazol-5-one (NTO) > nitroguanidine (NQ) > 2,4-dinitroanisole (DNAN) > 1,3,5-hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). A linear relationship between DNAN dissolution and rainwater volume was observed (r2 0.86-0.99). It was estimated that it would take 16-228 years to completely dissolve these formulation particles under natural environmental conditions in Oracle, AZ. We used LC/MS/MS and GC/MS to examine the dissolution samples from IMX-101 and 104 particles exposed to rainfall and sunlight and found six DNAN photo-transformation products including 2-methoxy-5-nitrophenol, 4-methoxy-3-nitrophenol, 4-methoxy-3-nitroaniline, 2-methoxy-5-nitroaniline, 2,4-dinitrophenol, and methoxy-dinitrophenol, which are in good agreement with computational modeling results of bond strengths. The main DNAN photodegradation pathways are therefore proposed. Predicted eco-toxicity values suggested that the parent compound DNAN, methoxy-nitrophenols, methoxy-nitroanilines and the other two products (2,4-dinitrophenol and methoxy-dinitrophenol) would be harmful to fish and daphnid. Our study provides improved insight about the rain dissolution and photochemical behavior of IM formulations under natural conditions, which helps to form target-oriented strategies to mitigate explosive contamination in military training sites.A requirement of the Construction Products Regulation (CPR) in the European Union states that construction works must be designed in such a way that throughout their entire life cycle, they have no exceedingly high environmental impact. The objective of the current work was to simulate the leaching of selected metals and sulfate in vertical test panels (VTPs) covered by plaster and mortar. The investigation is based on 18-month leaching outdoor tests (LOT) under real weather conditions. A leaching model was developed using the geochemical model PHREEQC with the Lawrence Livermore National Laboratory (LLNL) thermodynamic data base and coupled with MATLAB in order to optimize the run-off and weather parameters. The model was calibrated by comparing the data from laboratory Dynamic Surface Leaching Tests (DSLT) with simulation results up to an acceptable fit. The parameters obtained were then used in the LOT simulations and validated. The model allows predictions on the substance discharge from various plasters and mortars under real weather conditions. Physical characteristics of the material (e.g., thickness and absorption capacity) play an important role in the leaching of substances in façades covered with plaster and mortar. https://www.selleckchem.com/products/xmd8-92.html The lower the thickness and absorption capacity of the material applied, the greater the run-off and discharge of leached substances.Currently, seawater desalination based on air-water interface solar heating has triggered significant research interests because it effectively makes use of the solar energy and avoids fossil fuel consumption. However, to prevent the volatile organic compounds (VOCs) from volatilizing with water vapor which later will liquefy and enter the condensed freshwater is still a challenge. In this work, a g-C3N4/MoS2 based floating solar still (CM-FSS) combined with thermal/light activation of persulfate (PS) at air-water interface was applied for clean freshwater production for the first time. The CM-FSS was composed of a g-C3N4/MoS2 top layer for solar absorption, simultaneous thermal/light activation of PS and then VOCs degradation at air-water interface, a floating layer of expandable polyethylene (EPE) foam for heat isolation, and a transport channel of air-laid paper (ALP) for seawater and PS solution delivery. The water evaporation rate of the CM-FSS was measured at 1.23 kg m-2 h-1 under 1 kW m-2, which is 4.09 times higher than that of pure water without an evaporator. With the assistance of g-C3N4/MoS2 photocatalytic degradation and thermal/light activation of PS at the air-water interface, a high removal efficiency of a selected model VOCs pollutant of nitrobenzene (NB) could reach to 98.2% in condensed freshwater. Finally, when real seawater samples were employed as source water for solar distillation, the typical water-quality indices such as salinity, turbidity, anions, cations and organics of the condensed freshwater were below the limit values of the Standards for Drinking Water Quality in WHO, US EPA and China.Brominated benzenes and phenols constitute direct precursors in the formation of bromine-bearing pollutants; most notably PBDD/Fs and other dioxin-type compounds. Elucidating accurate mechanisms and constructing robust kinetic models for the oxidative transformation of bromobenzenes and bromophenols into notorious Br-toxicants entail a comprehensive understanding of their initial oxidation steps. However, pertinent mechanistic studies, based on quantum chemical calculations, have only focused on secondary condensation reactions into PBDD/Fs and PBDEs. Literature provide kinetic parameters for these significant reactions, nonetheless, without attempting to compile the acquired Arrhenius coefficients into kinetic models. To fill in this gap, this study sets out to illustrate primary chemical phenomena underpinning the low-temperature combustion of a monobromobenzene molecule (MBZ) based on a detail chemical kinetic model. The main aim is to map out temperature-dependent profiles for major intermediates and products.
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  • Total harmonic distortion (THD) plays an important role in the performance of miniature loudspeakers used in mobile phones. Traditional nonlinear models fail to predict THD in the higher frequency domain. Significant discrepancies can be found between the prediction and measurement. In this study, an extended model considering nonlinear acoustic damping is proposed to address this issue. Flow separation occurring near the orifices of the sound port is of particular interest. Two velocity-dependent parameters were derived to model the nonlinear damping effect. https://www.selleckchem.com/products/az20.html Based on the extended model, the dynamics of miniature loudspeakers are described using the state-space method. Experiments and calculations confirm the validity of the extended model. The influence of nonlinear acoustic damping on THD is also discussed.This paper deals with the experimental study of an acoustic Parity-Time (PT) symmetric system based on the thermoacoustic amplification process. Such a system is presented and consists of two acoustic units connected through side branches to a waveguide. One unit contains a thermoacoustic core that provides an acoustic gain which balances the thermal and viscous losses taking place in the second unit. Two control parameters are set to adjust the impedance of the two units and thereby achieve the PT-symmetry condition. The results show that a good balance between gain and loss is achieved within a frequency range from 45 Hz to 60 Hz. The spontaneous PT-symmetry breaking and the existence of exceptional points, which are characteristic of the behavior of PT-symmetric systems, are explored in this frequency range. Moreover, the distance between the two units is shown to be a control parameter to slightly shift the frequency at which the exceptional points occur.Progress in instrumentation, computer hardware, and inversion methods is encouraging the development of more advanced guided wave tomography techniques, especially for nondestructive testing of plate structures to characterize corrosion. An experimental S0 tomography performance assessment in the membrane regime is reported. One of the main interests of the fundamental membrane regime is that in this regime, waves are propagated over long distances. A 2 mm thick steel disk containing calibrated sharp artificial defects (flat bottom holes) is tested in both reflection and extinction modes. A reconstruction algorithm derived from the membrane approximation is presented. We expose a complete reflection mode inversion approach that includes beam inversion, waveform deconvolution, and thickness loss calibration. Non-linear correction factors are introduced and discussed for quantitative imaging. A width-regularity-depth description of defects is introduced to put the results into perspective with other defect geometries. The results show the relevance of the inversion method to enhance the imaging performance with regard to defect localization and sizing. Crucial points concerning instrumentation such as coupling, signal-to-noise ratio, excitation mode, coupling, selection of frequency, are also discussed.This paper presents a method to characterize the effective properties of inertial acoustic metamaterial unit cells for underwater operation. The method is manifested by a fast and reliable parameter retrieval procedure utilizing both numerical simulations and measurements. The effectiveness of the method was proved to be self-consistent by a metamaterial unit cell composed of aluminum honeycomb panels with soft rubber spacers. Simulated results agree well with the measured responses of this metamaterial in a water-filled resonator tube. A sub-unity density ratio and an anisotropic mass density are simultaneously achieved by the metamaterial unit cell, making it useful in implementations of transformation acoustics. The metamaterial, together with the approach for its characterization, are expected to be useful for underwater acoustic devices.A numerical simulation of a single-reed instrument with a pressure chamber is conducted to examine the interaction among the flow, reed oscillation, and acoustic propagation. The flow and acoustic fields are predicted using the three-dimensional compressible Navier-Stokes equations, whereas the one-dimensional dynamic beam equation is solved for reed oscillation. The deforming geometry in the aeroacoustic field is expressed by the volume penalization method as an immersed boundary technique. The results showed that the waveforms of the tip opening and far-field acoustic spectra agreed well with those measured experimentally. The three-dimensional flow configuration near the tip opening was visualized, and the measurement of the instantaneous volume flow rate at the tip opening revealed that 30%-40% of the total flow rate passed through the side opening. The spectral tendencies of the time derivatives of the flow rate for different tip openings were consistent with that of the far-field sound, indicating that the slope of the flow rate waveform significantly affects the generated sound's harmonics.Although human speech radiation has been a subject of considerable interest for decades, researchers have not previously measured its directivity over a complete sphere with high spatial and spectral resolution using live phonetically balanced passages. The research reported in this paper addresses this deficiency by employing a multiple-capture transfer function technique and spherical harmonic expansions. The work involved eight subjects and 2522 unique sampling positions over a 1.22 or 1.83 m sphere with 5° polar and azimuthal-angle increments. The paper explains the methods and directs readers to archived results for further exploration, modeling, and speech simulation in acoustical environments. Comparisons of the results to those of a KEMAR head-and-torso simulator, lower-resolution single-capture measurements, other authors' work, and basic symmetry expectations all substantiate their validity. The completeness and high resolution of the measurements offer insights into spherical speech directivity patterns that will aid researchers in the speech sciences, architectural acoustics, audio, and communications.
    Total harmonic distortion (THD) plays an important role in the performance of miniature loudspeakers used in mobile phones. Traditional nonlinear models fail to predict THD in the higher frequency domain. Significant discrepancies can be found between the prediction and measurement. In this study, an extended model considering nonlinear acoustic damping is proposed to address this issue. Flow separation occurring near the orifices of the sound port is of particular interest. Two velocity-dependent parameters were derived to model the nonlinear damping effect. https://www.selleckchem.com/products/az20.html Based on the extended model, the dynamics of miniature loudspeakers are described using the state-space method. Experiments and calculations confirm the validity of the extended model. The influence of nonlinear acoustic damping on THD is also discussed.This paper deals with the experimental study of an acoustic Parity-Time (PT) symmetric system based on the thermoacoustic amplification process. Such a system is presented and consists of two acoustic units connected through side branches to a waveguide. One unit contains a thermoacoustic core that provides an acoustic gain which balances the thermal and viscous losses taking place in the second unit. Two control parameters are set to adjust the impedance of the two units and thereby achieve the PT-symmetry condition. The results show that a good balance between gain and loss is achieved within a frequency range from 45 Hz to 60 Hz. The spontaneous PT-symmetry breaking and the existence of exceptional points, which are characteristic of the behavior of PT-symmetric systems, are explored in this frequency range. Moreover, the distance between the two units is shown to be a control parameter to slightly shift the frequency at which the exceptional points occur.Progress in instrumentation, computer hardware, and inversion methods is encouraging the development of more advanced guided wave tomography techniques, especially for nondestructive testing of plate structures to characterize corrosion. An experimental S0 tomography performance assessment in the membrane regime is reported. One of the main interests of the fundamental membrane regime is that in this regime, waves are propagated over long distances. A 2 mm thick steel disk containing calibrated sharp artificial defects (flat bottom holes) is tested in both reflection and extinction modes. A reconstruction algorithm derived from the membrane approximation is presented. We expose a complete reflection mode inversion approach that includes beam inversion, waveform deconvolution, and thickness loss calibration. Non-linear correction factors are introduced and discussed for quantitative imaging. A width-regularity-depth description of defects is introduced to put the results into perspective with other defect geometries. The results show the relevance of the inversion method to enhance the imaging performance with regard to defect localization and sizing. Crucial points concerning instrumentation such as coupling, signal-to-noise ratio, excitation mode, coupling, selection of frequency, are also discussed.This paper presents a method to characterize the effective properties of inertial acoustic metamaterial unit cells for underwater operation. The method is manifested by a fast and reliable parameter retrieval procedure utilizing both numerical simulations and measurements. The effectiveness of the method was proved to be self-consistent by a metamaterial unit cell composed of aluminum honeycomb panels with soft rubber spacers. Simulated results agree well with the measured responses of this metamaterial in a water-filled resonator tube. A sub-unity density ratio and an anisotropic mass density are simultaneously achieved by the metamaterial unit cell, making it useful in implementations of transformation acoustics. The metamaterial, together with the approach for its characterization, are expected to be useful for underwater acoustic devices.A numerical simulation of a single-reed instrument with a pressure chamber is conducted to examine the interaction among the flow, reed oscillation, and acoustic propagation. The flow and acoustic fields are predicted using the three-dimensional compressible Navier-Stokes equations, whereas the one-dimensional dynamic beam equation is solved for reed oscillation. The deforming geometry in the aeroacoustic field is expressed by the volume penalization method as an immersed boundary technique. The results showed that the waveforms of the tip opening and far-field acoustic spectra agreed well with those measured experimentally. The three-dimensional flow configuration near the tip opening was visualized, and the measurement of the instantaneous volume flow rate at the tip opening revealed that 30%-40% of the total flow rate passed through the side opening. The spectral tendencies of the time derivatives of the flow rate for different tip openings were consistent with that of the far-field sound, indicating that the slope of the flow rate waveform significantly affects the generated sound's harmonics.Although human speech radiation has been a subject of considerable interest for decades, researchers have not previously measured its directivity over a complete sphere with high spatial and spectral resolution using live phonetically balanced passages. The research reported in this paper addresses this deficiency by employing a multiple-capture transfer function technique and spherical harmonic expansions. The work involved eight subjects and 2522 unique sampling positions over a 1.22 or 1.83 m sphere with 5° polar and azimuthal-angle increments. The paper explains the methods and directs readers to archived results for further exploration, modeling, and speech simulation in acoustical environments. Comparisons of the results to those of a KEMAR head-and-torso simulator, lower-resolution single-capture measurements, other authors' work, and basic symmetry expectations all substantiate their validity. The completeness and high resolution of the measurements offer insights into spherical speech directivity patterns that will aid researchers in the speech sciences, architectural acoustics, audio, and communications.
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