As a clean energy resource, coalbed methane (CBM) has drawn worldwide attention. However, the CBM reservoir has strong adsorption capacity and low permeability and thus requires stimulation. As a means to stimulate coalbed methane recovery, thermal injection faces geological and economic challenges because it uses conventional conductive heating (CH) to transfer heat. Realized by the conversion of the electromagnetic energy into the thermal energy, microwave heating (MH) may be a sound stimulation method. Although previous research suggested that MH had potential as a stimulation method for coalbed methane recovery, it is not clear if MH is superior to CH for enhancing coalbed methane recovery. This paper compares the effect of MH and CH on methane desorption from coal using purpose-built experimental equipment. To compare the MH and CH experimental results, the desorption temperature for each CH desorption test was set to the maximum temperature reached in the correlative MH desorption test. The results show that although the cumulative desorbed volume (CDV) of methane under MH was less than that desorbed by CH in the initial desorption stage, the final total CDV under MH for the three different power settings was ~ 12% to ~ 21% more than that desorbed by CH at the same temperatures. CH and MH both change the sample's microstructure but MH enlarges the pores, decreases methane adsorption, promotes methane diffusion, and improves permeability more effectively than CH. Rapid temperature rise and the changes in the coal's microstructure caused by MH were the main reasons for its superior performance. These findings may provide reference for selecting the most appropriate type of heating for thermal injection assisted coalbed methane recovery.Patients and breast cancer surgeons are frequently confronted with wound complications after mastectomy. Negative pressure wound therapy (NPWT) is a promising technique for preventing wound complications after skin closure in elective surgery. However, a clinical study evaluating postoperative complications following the use of NPWT, focusing solely on closed incisions in patients undergoing mastectomy, has yet to be performed. Between June 2019 and February 2020, 50 consecutive patients underwent mastectomy with NPWT during the first seven postoperative days. This group was compared to a cohort of patients taking part in a randomized controlled trial between June 2014 and July 2018. Primary outcome was the rate of postoperative wound complications, i.e. surgical site infections, wound necrosis or wound dehiscence during the first three postoperative months. Secondary outcomes were the number of patients requiring unplanned visits to the hospital and developing clinically significant seroma (CSS). In total, 161 patients were analyzed, of whom 111 patients in the control group (CON) and 50 patients in the NPWT group (NPWT). Twenty-eight percent of the patients in the NPWT group developed postoperative wound complications, compared to 18.9% in the control group (OR = 1.67 (95% CI 0.77-3.63), p = 0.199). The number of patients requiring unplanned visits or developing CSS was not statistically significant between the groups. https://www.selleckchem.com/products/slf1081851-hydrochloride.html This study suggests that Avelle negative pressure wound therapy in mastectomy wounds does not lead to fewer postoperative wound complications. Additionally, it does not lead to fewer patients requiring unplanned visits or fewer patients developing clinically significant seromas.Trial registration ClinicalTrials.gov number, NCT03942575. Date of registration 08/05/2019.Although exercise is widely recommended for survivors of cancer, readily implementable approaches for evaluating exercise tolerance enabling exercise prescriptions at appropriate levels of cardiovascular exertion are not always available. We evaluated the utility of modified Harvard Step tests within the context of a standard physical examination for fitness evaluation and exercise prescription for survivors of cancer across a range of age, BMI and exercise history. While 52% of presenting individuals with a past cancer diagnosis were able to complete a 3-min test at pace with a reduced 9-in. step, adoption of self-determined pacing, test duration and completion on a flat surface enabled relative fitness rating and appropriate exercise prescription for the remaining survivors. Younger age and more vigorous exercise histories correlated with completion of the standard 3-min test at pace, but all 9-in. formats led to exercise prescriptions more vigorous than current activity. The physical examination setting expedited inclusion of core and specific muscle group strength testing. The approach is adaptable to a range of health care settings, providers, and patients, providing a shared opportunity for providers and patients to evaluate exercise tolerance. It can be used to further expand incorporation of exercise testing and prescription into routine care.Thermophilic organisms are extensively studied in industrial biotechnology, for exploration of the limits of life, and in other contexts. Their optimal growth at high temperatures presents a challenge for the development of genetic tools for their genome editing, since genetic markers and selection substrates are often thermolabile. We sought to develop a thermostable CRISPR-Cas9 based system for genome editing of thermophiles. We identified CaldoCas9 and designed an associated guide RNA and showed that the pair have targetable nuclease activity in vitro at temperatures up to 65 °C. We performed a detailed characterization of the protospacer adjacent motif specificity of CaldoCas9, which revealed a preference for 5'-NNNNGNMA. We constructed a plasmid vector for the delivery and use of the CaldoCas9 based genome editing system in the extreme thermophile Thermus thermophilus at 65 °C. Using the vector, we generated gene knock-out mutants of T. thermophilus, targeting genes on the bacterial chromosome and megaplasmid. Mutants were obtained at a frequency of about 90%. We demonstrated that the vector can be cured from mutants for a subsequent round of genome editing. CRISPR-Cas9 based genome editing has not been reported previously in the extreme thermophile T. thermophilus. These results may facilitate development of genome editing tools for other extreme thermophiles and to that end, the vector has been made available via the plasmid repository Addgene.
As a clean energy resource, coalbed methane (CBM) has drawn worldwide attention. However, the CBM reservoir has strong adsorption capacity and low permeability and thus requires stimulation. As a means to stimulate coalbed methane recovery, thermal injection faces geological and economic challenges because it uses conventional conductive heating (CH) to transfer heat. Realized by the conversion of the electromagnetic energy into the thermal energy, microwave heating (MH) may be a sound stimulation method. Although previous research suggested that MH had potential as a stimulation method for coalbed methane recovery, it is not clear if MH is superior to CH for enhancing coalbed methane recovery. This paper compares the effect of MH and CH on methane desorption from coal using purpose-built experimental equipment. To compare the MH and CH experimental results, the desorption temperature for each CH desorption test was set to the maximum temperature reached in the correlative MH desorption test. The results show that although the cumulative desorbed volume (CDV) of methane under MH was less than that desorbed by CH in the initial desorption stage, the final total CDV under MH for the three different power settings was ~ 12% to ~ 21% more than that desorbed by CH at the same temperatures. CH and MH both change the sample's microstructure but MH enlarges the pores, decreases methane adsorption, promotes methane diffusion, and improves permeability more effectively than CH. Rapid temperature rise and the changes in the coal's microstructure caused by MH were the main reasons for its superior performance. These findings may provide reference for selecting the most appropriate type of heating for thermal injection assisted coalbed methane recovery.Patients and breast cancer surgeons are frequently confronted with wound complications after mastectomy. Negative pressure wound therapy (NPWT) is a promising technique for preventing wound complications after skin closure in elective surgery. However, a clinical study evaluating postoperative complications following the use of NPWT, focusing solely on closed incisions in patients undergoing mastectomy, has yet to be performed. Between June 2019 and February 2020, 50 consecutive patients underwent mastectomy with NPWT during the first seven postoperative days. This group was compared to a cohort of patients taking part in a randomized controlled trial between June 2014 and July 2018. Primary outcome was the rate of postoperative wound complications, i.e. surgical site infections, wound necrosis or wound dehiscence during the first three postoperative months. Secondary outcomes were the number of patients requiring unplanned visits to the hospital and developing clinically significant seroma (CSS). In total, 161 patients were analyzed, of whom 111 patients in the control group (CON) and 50 patients in the NPWT group (NPWT). Twenty-eight percent of the patients in the NPWT group developed postoperative wound complications, compared to 18.9% in the control group (OR = 1.67 (95% CI 0.77-3.63), p = 0.199). The number of patients requiring unplanned visits or developing CSS was not statistically significant between the groups. https://www.selleckchem.com/products/slf1081851-hydrochloride.html This study suggests that Avelle negative pressure wound therapy in mastectomy wounds does not lead to fewer postoperative wound complications. Additionally, it does not lead to fewer patients requiring unplanned visits or fewer patients developing clinically significant seromas.Trial registration ClinicalTrials.gov number, NCT03942575. Date of registration 08/05/2019.Although exercise is widely recommended for survivors of cancer, readily implementable approaches for evaluating exercise tolerance enabling exercise prescriptions at appropriate levels of cardiovascular exertion are not always available. We evaluated the utility of modified Harvard Step tests within the context of a standard physical examination for fitness evaluation and exercise prescription for survivors of cancer across a range of age, BMI and exercise history. While 52% of presenting individuals with a past cancer diagnosis were able to complete a 3-min test at pace with a reduced 9-in. step, adoption of self-determined pacing, test duration and completion on a flat surface enabled relative fitness rating and appropriate exercise prescription for the remaining survivors. Younger age and more vigorous exercise histories correlated with completion of the standard 3-min test at pace, but all 9-in. formats led to exercise prescriptions more vigorous than current activity. The physical examination setting expedited inclusion of core and specific muscle group strength testing. The approach is adaptable to a range of health care settings, providers, and patients, providing a shared opportunity for providers and patients to evaluate exercise tolerance. It can be used to further expand incorporation of exercise testing and prescription into routine care.Thermophilic organisms are extensively studied in industrial biotechnology, for exploration of the limits of life, and in other contexts. Their optimal growth at high temperatures presents a challenge for the development of genetic tools for their genome editing, since genetic markers and selection substrates are often thermolabile. We sought to develop a thermostable CRISPR-Cas9 based system for genome editing of thermophiles. We identified CaldoCas9 and designed an associated guide RNA and showed that the pair have targetable nuclease activity in vitro at temperatures up to 65 °C. We performed a detailed characterization of the protospacer adjacent motif specificity of CaldoCas9, which revealed a preference for 5'-NNNNGNMA. We constructed a plasmid vector for the delivery and use of the CaldoCas9 based genome editing system in the extreme thermophile Thermus thermophilus at 65 °C. Using the vector, we generated gene knock-out mutants of T. thermophilus, targeting genes on the bacterial chromosome and megaplasmid. Mutants were obtained at a frequency of about 90%. We demonstrated that the vector can be cured from mutants for a subsequent round of genome editing. CRISPR-Cas9 based genome editing has not been reported previously in the extreme thermophile T. thermophilus. These results may facilitate development of genome editing tools for other extreme thermophiles and to that end, the vector has been made available via the plasmid repository Addgene.
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