Wearable ultrasound devices represent a transformative advancement in therapeutic applications,offering noninvasive,continuous,and targeted treatment for deep tissues.These systems leverage flexible materials(e.g.,pie...Wearable ultrasound devices represent a transformative advancement in therapeutic applications,offering noninvasive,continuous,and targeted treatment for deep tissues.These systems leverage flexible materials(e.g.,piezoelectric composites,biodegradable polymers)and conformable designs to enable stable integration with dynamic anatomical surfaces.Key innovations include ultrasound-enhanced drug delivery through cavitation-mediated transdermal penetration,accelerated tissue regeneration via mechanical and electrical stimulation,and precise neuromodulation using focused acoustic waves.Recent developments demonstrate wireless operation,real-time monitoring,and closed-loop therapy,facilitated by energy-efficient transducers and AI-driven adaptive control.Despite progress,challenges persist in material durability,clinical validation,and scalable manufacturing.Future directions highlight the integration of nanomaterials,3D-printed architectures,and multimodal sensing for personalized medicine.This technology holds significant potential to redefine chronic disease management,postoperative recovery,and neurorehabilitation,bridging the gap between clinical and home-based care.展开更多
Hyperlipidemia constitutes a critical factor in the pathogenesis of vascular disease and gut microbiota dysbiosis.This study aims to investigate the role of sea buckthorn fruit oil(SBFO)in ameliorating hyperlipidemia,...Hyperlipidemia constitutes a critical factor in the pathogenesis of vascular disease and gut microbiota dysbiosis.This study aims to investigate the role of sea buckthorn fruit oil(SBFO)in ameliorating hyperlipidemia,modulating gut microbiota,and elucidating the underlying mechanisms of its lipid-lowering effects.SBFO intervention in hyperlipidemic mice significantly reduced body weight and visceral adiposity index while mitigating symptoms associated with hyperlipidemia,including dyslipidemia,infla mmation,liver damage,and endothelial dysfunction.Real-time quantitative PCR and Western blot analyses revealed that SBFO enhanced the response of free fatty acid oxidation and breakdown(adenosine 5'-monophosphateactivated protein kinaseα,carnitine palmitoyltransferase1a,peroxisome proliferator-activated receptorα,and peroxisome proliferator-activated receptorγ)while suppressing the synthesis of triglycerides and fatty acids(sterol-regulatory element binding protein 1,fatty acid synthase,and acetyl CoA carboxylase)at the gene and protein expression levels.Moreover,SBFO intervention enriched the gut microbiota of hyperlipidemic mice by increasing the relative abundances of Lactobacillus,Faecalibaculum,and Allobaculum,while decreasing the Firmicutes/Bacteroidetes ratio.These findings suggest that SBFO exhibits promising therapeutic potential in attenuating hyperlipidemia in mice through the regulation of lipid metabolism and modulation of gut microbiota.展开更多
The plateau environment not only affects the development of concrete's early strength but also damages its durability during its service life.This paper summarized and analyzed the impact of plateau environments o...The plateau environment not only affects the development of concrete's early strength but also damages its durability during its service life.This paper summarized and analyzed the impact of plateau environments on concrete’properties and proposed methods to improve the performance of concrete in plateau environment.The results indicated that low humidity and high evaporation rates in plateau regions inhibit the hydration of cement in concrete,leading to an increased content of micro-pores ranging from 500 to 1000 nm and raising the risk of early-stage cracking,thus reducing the impermeability of concrete.The low atmospheric pressure(AP)condition of 60 kPa decreases the entrained air content in concrete by over 20%,diminishes the pores under 200μm,and increases the average air-voids diameter and spacing factor,resulting in a decrease of more than 5%in the 28 d compressive strength of concrete.Consequently,the durability of concrete is compromised.Saponin and rosinbased air-entraining agents are recommended to improve the performance of concrete in plateau environments.Nanoparticles also aid in stabilizing bubbles in such conditions.Selecting low-heat specialty cements,increasing the amount of cement used,and extending the curing period are also vital measures to enhance the performance of plateau concrete.展开更多
Biotechnological strategies for plastic depolymerization and recycling have emerged as transformative approaches to combat the global plastic pollution crisis,aligning with the principles of a sustainable and circular...Biotechnological strategies for plastic depolymerization and recycling have emerged as transformative approaches to combat the global plastic pollution crisis,aligning with the principles of a sustainable and circular economy.Despite advances in engineering PET hydrolases,the degradation process is frequently compromised by product inhibition and the heterogeneity of final products,thereby obstructing subsequent PET recondensation and impeding the synthesis of high-value derivatives.In this work,we utilized previously devised computational strategies to redesign a thermostable DuraMHETase,achieving an apparent melting temperature of 72℃ in complex with MHET and a 6-fold higher in total turnover number(TTN)toward MHET than the wild-type enzyme at 60℃.The fused enzyme system composed of DuraMHETase and TurboPETase demonstrated higher efficiency than other PET hydrolases and the separated dual enzyme systems.Furthermore,we identified both exo-and endo-PETase activities in DuraMHETase,whereas the endo-activity was previously unobserved at ambient temperatures.These results expand the functional scope of MHETase beyond mere intermediate hydrolysis,and may provide guidance for the development of more synergistic approaches to plastic biodepolymerization and recycling.展开更多
Obesity is a major focus of researchers due to its increasing prevalence and relationship with other diseases,such as cancer and cardiovascular diseases.Probiotics are active microorganisms and have been proven to all...Obesity is a major focus of researchers due to its increasing prevalence and relationship with other diseases,such as cancer and cardiovascular diseases.Probiotics are active microorganisms and have been proven to alleviate obesity by modulating the microbiota.In this study,we found that oral administration of Bifidobacterium adolescentis CCFM8630 to obese mice inhibited high-fat diet(HFD)-induced changes in body weight and adipose tissue and alleviated hepatic oxidative stress.Furthermore,B.adolescentis CCFM8630 treatment primarily affected the relative abundances of the phyla Proteobacteria and Actinobacteria,and thereby decreased the production of lipopolysaccharide(LPS)and the occurrence of LPS related diseases.A high fiber intake increased the abundance of Lactobacillus and the concentrations of short chain fatty acids in obese mice,but these changes were reversed by B.adolescentis CCFM8630 treatment.In addition,targeted metabolomic analysis and microbiota relationship analysis revealed that B.adolescentis CCFM8630 treatment modified the microbiota of obese mice by promoting the conversion of tryptophan(Trp)to xanthurenic acid,kynurenic acid,tryptamine,indole-3-acetic acid,and indole-3-carboxaldehyde;facilitated the expression of interleukin-17A and the aryl hydrocarbon receptor to generate interleukin-22 in the colon;and upregulated the expression of tight junction proteins,thereby strengthening intestinal barriers.In summary,our findings suggest that the intake of B.adolescentis CCFM8630 may alleviate obesity by modulating the gut microbiota and related Trp metabolism.展开更多
Melasma is a prevalent and challenging skin condition that affects the face and causes distress in many patients and physicians.Tranexamic acid(TA)has been found to be effective for treating melasma and can be adminis...Melasma is a prevalent and challenging skin condition that affects the face and causes distress in many patients and physicians.Tranexamic acid(TA)has been found to be effective for treating melasma and can be administered through multiple routes.This review details the mechanisms of action of TA in treatment of melasma and assesses the efficacy and safety associated with different administrations,which can contribute to selecting appropriate melasma treatment plan for different patients.展开更多
Aromatic ketones,such as 9-fluorenone(9-FO),are known for their high intersystem crossing quantum yields(Φ_(ISC)≈1),rendering them highly valuable for photochemical reactions and dye-sensitized solar cells.However,t...Aromatic ketones,such as 9-fluorenone(9-FO),are known for their high intersystem crossing quantum yields(Φ_(ISC)≈1),rendering them highly valuable for photochemical reactions and dye-sensitized solar cells.However,their use as photosensitizers in biological contexts has been hindered by their low extinction coefficients,high excitation energies,and weak fluorescence.To address these limitations,we conjugated 9-FO with a fused-ring electron donor,resulting in an acceptor-donor-acceptor derivative IDT-9F.This strategy has successfully redshifted the absorption peak of 9-FO(380 nm)into the visible light range(498 nm)and significantly enhanced its light absorption capability(~310-fold)and fluorescence quantum yield(~100-fold).Furthermore,IDT-9F was encapsulated within pH-responsive nanoparticles using an acid-induced charge-reversal polymer as the amphiphilic matrix,and enabled fluorescence imaging-guided photodynamic inactivation of Gram-positive bacteria in acidic environment with a remarkable bacterial inhibition rate exceeding 99.9%.展开更多
Phase-change material(PCM)has a high potential to cool the drilling fluids for ultra-deep oil/gas wells and geothermal wells to ensure efficient drilling and resource exploitation.Because PCM tends to agglomerate and ...Phase-change material(PCM)has a high potential to cool the drilling fluids for ultra-deep oil/gas wells and geothermal wells to ensure efficient drilling and resource exploitation.Because PCM tends to agglomerate and seriously affect the properties of drilling fluid,it is necessary that the PCM is protected by a shell on its surface.In this study,a novel microencapsulated PCM(with a phase transition temperature of 130.5℃)with a SiO_(2) protection shell were obtained by using tetraethyl orthosilicate(TEOS)as silicon source via a sol-gel process.PCM microcapsules with optimal synthesis ratio of 3:4 have excellent warm blood characteristics and smooth shell.The addition of 5 wt%PCM microcapsules for accurate heat trapping and temperature control at 130℃ effectively delays the time of drilling fluid reaching 150℃ by 42.5%,which improves the operability of drilling fluid at high cycle temperature.The results of this study can provide useful insights and information for use of PCM in ultra-deep oil/gas and geothermal wells.展开更多
The incorporation of fibers represents a crucial technique for improving the mechanical properties and other relevant characteristics of cement-based composites(CBC),including concrete,cement mortar,and oil-well cemen...The incorporation of fibers represents a crucial technique for improving the mechanical properties and other relevant characteristics of cement-based composites(CBC),including concrete,cement mortar,and oil-well cement.Especially,carbon fiber(CF)has a great potential for reinforcing oil-well cement due to its high strength,modulus,stiffness,high temperature,corrosion and fatigue resistance as well as chemical stability.There is a huge amount of waste CFs all over the world which show better performance in cement industry,while their reuse will realize waste recovery(good environment impact)and greatly reduce cost.This review paper presents the recent progress of using CF in enhancing mechanical properties of CBC.We put high emphasis on the CF surface modification for reinforcing bond strength at the cement/CF interface.Comprehensive discussion with respect to effects of CF and modified CF on CBC properties is performed.The key properties of CBC examined in this study encompass mechanical characteristics(compressive strength,flexural strength,and tensile strength),dimensional stability(shrinkage behavior),durability indicators(water absorption and permeability),and fracture-related properties(toughness,crack resistance,and impact performance).Thus,suggestions are given for the future study and application of CF in oil-well cement.展开更多
Background:The results of studies comparing Billroth-I(B-I)with Roux-en-Y(R-Y)reconstruction on the quality of life(QoL)are still inconsistent.The aim of this trial was to compare the long-term QoL of B-I with R-Y ana...Background:The results of studies comparing Billroth-I(B-I)with Roux-en-Y(R-Y)reconstruction on the quality of life(QoL)are still inconsistent.The aim of this trial was to compare the long-term QoL of B-I with R-Y anastomosis after curative distal gastrectomy for gastric cancer.Methods:A total of 140 patients undergoing curative distal gastrectomy with D2 lymphadenectomy in West China Hospital,Sichuan University from May 2011 to May 2014 were randomly assigned to the B-I group(N=70)and R-Y group(N=70).The follow-up time points were 1,3,6,9,12,24,36,48,and 60 months after the operation.The final follow-up time was May 2019.The clinicopathological features,operative safety,postoperative recovery,long-term survival as well as QoL were compared,among which QoL score was the primary outcome.An intention-to-treat analysis was applied.Results:The baseline characteristics were comparable between the two groups.There were no statistically significant differences in terms of postoperative morbidity and mortality rates,and postoperative recovery between the two groups.Less estimated blood loss and shorter surgical duration were found in the B-I group.There were no statistically significant differences in 5-year overall survival(79%[55/70]of the B-I group vs.80%[56/70]of the R-Y group,P=0.966)and recurrence-free survival rates(79%[55/70]of the B-I group vs.78%[55/70]of the R-Y group,P=0.979)between the two groups.The scores of the global health status of the R-Y group were higher than those of the B-I group with statistically significant differences(postoperative 1 year:85.4±13.1 vs.88.8±16.1,P=0.033;postoperative 3 year:87.3±15.2 vs.92.8±11.3,P=0.028;postoperative 5 year:90.9±13.7 vs.96.4±5.6,P=0.010),and the reflux(postoperative 3 year:8.8±12.9 vs.2.8±5.3,P=0.001;postoperative 5 year:5.1±9.8 vs.1.8±4.7,P=0.033)and epigastric pain(postoperative 1 year:11.8±12.7 vs.6.1±8.8,P=0.008;postoperative 3 year:9.4±10.6 vs.4.6±7.9,P=0.006;postoperative 5 year:6.0±8.9 vs.2.7±4.6,P=0.022)were milder in the R-Y group than those of the B-I group at the postoperative 1,3,and 5-year time points.Conclusions:Compared with B-I group,R-Y reconstruction was associated with better long-term QoL by reducing reflux and epigastric pain,without changing survival outcomes.Trial Registration:ChiCTR.org.cn,ChiCTR-TRC-10001434.展开更多
In order to solve the problem of poor thermal insulation in the current wood-plastic building,two kinds of structural wood wall integrated with wood plastic composite(WPC)are designed,and the thermal insulation perfor...In order to solve the problem of poor thermal insulation in the current wood-plastic building,two kinds of structural wood wall integrated with wood plastic composite(WPC)are designed,and the thermal insulation performances of the walls are studied.The results show that the WPC integrated wall with frame-shear structure has a good stability,and the excellent performance of the WPC can be fully realized.Wall studs and wall panels are important factors affecting the thermal performance of the walls.Wood plastic materials can meet the thermal performance requirements of the walls.The single-layer frame walls and double-layer frame walls integrated with the WPC both have a good thermal performance.According to‘Design Standard for Energy Efficiency of Public Buildings(GB 50189-2015)’,the heat transfer coefficient of the single-layer frame wall integrated with 20 mm thick WPC wall boards and WPC wall studs is 0.414 W/(m^(2)•K),which can meet the standard of wall thermal levelⅡt and is suitable for cold areas.The heat transfer coefficient of the double-layer frame wall integrated with 50 mm thick WPC wall panel and WPC wall studs is 0.207 W/(m^(2)•K),which can meet the standard of wall thermal levelⅠt and is suitable for severe cold areas.展开更多
The development of base editing(BE)technology has opened a new avenue for research studies in bacteriology,particularly for bacterial species in which the DNA double-strand breaks(DSBs)introduced by CRISPR/Cas system ...The development of base editing(BE)technology has opened a new avenue for research studies in bacteriology,particularly for bacterial species in which the DNA double-strand breaks(DSBs)introduced by CRISPR/Cas system would lead to cell death.However,a major limitation of BE-mediated gene editing is the restricted editable sites in the target bacterial genome due to highly diverse genomic compositions,such as GC content.Herein,we developed a broad-spectrum DNase-inactive Cpf1(dCpf1)variant from Francisella novicida(bsdFnCpf1)through directed evolution.The resulting optimized mutant showed a substantially expanded targeting range,including previously non-canonical protospacer-adjacent motifs(PAMs),especially the GC-rich PAMs.Cytidine deaminase APOBEC1 and uracil DNA glycosylase inhibitor(UGI)were fused with bsdFnCpf1 to achieve specific C to T mutations at multiple target sites with canonical or non-canonical PAMs in the E.coli genome without compromising cell growth.We anticipate that bsdFnCpf1 could be applied for multiplex gene regulation and BE in species that have been reported to be suitable for Cpf1.展开更多
基金the support from the start-up of the University of Missouri-Columbia。
文摘Wearable ultrasound devices represent a transformative advancement in therapeutic applications,offering noninvasive,continuous,and targeted treatment for deep tissues.These systems leverage flexible materials(e.g.,piezoelectric composites,biodegradable polymers)and conformable designs to enable stable integration with dynamic anatomical surfaces.Key innovations include ultrasound-enhanced drug delivery through cavitation-mediated transdermal penetration,accelerated tissue regeneration via mechanical and electrical stimulation,and precise neuromodulation using focused acoustic waves.Recent developments demonstrate wireless operation,real-time monitoring,and closed-loop therapy,facilitated by energy-efficient transducers and AI-driven adaptive control.Despite progress,challenges persist in material durability,clinical validation,and scalable manufacturing.Future directions highlight the integration of nanomaterials,3D-printed architectures,and multimodal sensing for personalized medicine.This technology holds significant potential to redefine chronic disease management,postoperative recovery,and neurorehabilitation,bridging the gap between clinical and home-based care.
基金supported by the National Natural Science Foundation of China(31201416)Programme of Introducing Talents of Discipline to Universities(B17018)。
文摘Hyperlipidemia constitutes a critical factor in the pathogenesis of vascular disease and gut microbiota dysbiosis.This study aims to investigate the role of sea buckthorn fruit oil(SBFO)in ameliorating hyperlipidemia,modulating gut microbiota,and elucidating the underlying mechanisms of its lipid-lowering effects.SBFO intervention in hyperlipidemic mice significantly reduced body weight and visceral adiposity index while mitigating symptoms associated with hyperlipidemia,including dyslipidemia,infla mmation,liver damage,and endothelial dysfunction.Real-time quantitative PCR and Western blot analyses revealed that SBFO enhanced the response of free fatty acid oxidation and breakdown(adenosine 5'-monophosphateactivated protein kinaseα,carnitine palmitoyltransferase1a,peroxisome proliferator-activated receptorα,and peroxisome proliferator-activated receptorγ)while suppressing the synthesis of triglycerides and fatty acids(sterol-regulatory element binding protein 1,fatty acid synthase,and acetyl CoA carboxylase)at the gene and protein expression levels.Moreover,SBFO intervention enriched the gut microbiota of hyperlipidemic mice by increasing the relative abundances of Lactobacillus,Faecalibaculum,and Allobaculum,while decreasing the Firmicutes/Bacteroidetes ratio.These findings suggest that SBFO exhibits promising therapeutic potential in attenuating hyperlipidemia in mice through the regulation of lipid metabolism and modulation of gut microbiota.
基金funded by the National Natural Science Foundation of China(No.52278429)the Key R&D Program in Shaanxi Province(Nos.2023-ZDLGY-25,2025SF-YBXM-537)+1 种基金the Fundamental Research Funds for the Central Universities,CHD(No.300102315203)Transportation Science and Technology Project in Shaanxi Province(Nos.23-91K,24-14K,24-39K).
文摘The plateau environment not only affects the development of concrete's early strength but also damages its durability during its service life.This paper summarized and analyzed the impact of plateau environments on concrete’properties and proposed methods to improve the performance of concrete in plateau environment.The results indicated that low humidity and high evaporation rates in plateau regions inhibit the hydration of cement in concrete,leading to an increased content of micro-pores ranging from 500 to 1000 nm and raising the risk of early-stage cracking,thus reducing the impermeability of concrete.The low atmospheric pressure(AP)condition of 60 kPa decreases the entrained air content in concrete by over 20%,diminishes the pores under 200μm,and increases the average air-voids diameter and spacing factor,resulting in a decrease of more than 5%in the 28 d compressive strength of concrete.Consequently,the durability of concrete is compromised.Saponin and rosinbased air-entraining agents are recommended to improve the performance of concrete in plateau environments.Nanoparticles also aid in stabilizing bubbles in such conditions.Selecting low-heat specialty cements,increasing the amount of cement used,and extending the curing period are also vital measures to enhance the performance of plateau concrete.
文摘Biotechnological strategies for plastic depolymerization and recycling have emerged as transformative approaches to combat the global plastic pollution crisis,aligning with the principles of a sustainable and circular economy.Despite advances in engineering PET hydrolases,the degradation process is frequently compromised by product inhibition and the heterogeneity of final products,thereby obstructing subsequent PET recondensation and impeding the synthesis of high-value derivatives.In this work,we utilized previously devised computational strategies to redesign a thermostable DuraMHETase,achieving an apparent melting temperature of 72℃ in complex with MHET and a 6-fold higher in total turnover number(TTN)toward MHET than the wild-type enzyme at 60℃.The fused enzyme system composed of DuraMHETase and TurboPETase demonstrated higher efficiency than other PET hydrolases and the separated dual enzyme systems.Furthermore,we identified both exo-and endo-PETase activities in DuraMHETase,whereas the endo-activity was previously unobserved at ambient temperatures.These results expand the functional scope of MHETase beyond mere intermediate hydrolysis,and may provide guidance for the development of more synergistic approaches to plastic biodepolymerization and recycling.
基金supported by the National Natural Science Foundation of China(32272332,32021005,31820103010)the Fundamental Research Funds for the Central Universities(JUSRP622020,JUSRP22006,JUSRP51501)the Program of Collaborative Innovation Centre of Food Safety and Quality Control in Jiangsu Province.
文摘Obesity is a major focus of researchers due to its increasing prevalence and relationship with other diseases,such as cancer and cardiovascular diseases.Probiotics are active microorganisms and have been proven to alleviate obesity by modulating the microbiota.In this study,we found that oral administration of Bifidobacterium adolescentis CCFM8630 to obese mice inhibited high-fat diet(HFD)-induced changes in body weight and adipose tissue and alleviated hepatic oxidative stress.Furthermore,B.adolescentis CCFM8630 treatment primarily affected the relative abundances of the phyla Proteobacteria and Actinobacteria,and thereby decreased the production of lipopolysaccharide(LPS)and the occurrence of LPS related diseases.A high fiber intake increased the abundance of Lactobacillus and the concentrations of short chain fatty acids in obese mice,but these changes were reversed by B.adolescentis CCFM8630 treatment.In addition,targeted metabolomic analysis and microbiota relationship analysis revealed that B.adolescentis CCFM8630 treatment modified the microbiota of obese mice by promoting the conversion of tryptophan(Trp)to xanthurenic acid,kynurenic acid,tryptamine,indole-3-acetic acid,and indole-3-carboxaldehyde;facilitated the expression of interleukin-17A and the aryl hydrocarbon receptor to generate interleukin-22 in the colon;and upregulated the expression of tight junction proteins,thereby strengthening intestinal barriers.In summary,our findings suggest that the intake of B.adolescentis CCFM8630 may alleviate obesity by modulating the gut microbiota and related Trp metabolism.
文摘Melasma is a prevalent and challenging skin condition that affects the face and causes distress in many patients and physicians.Tranexamic acid(TA)has been found to be effective for treating melasma and can be administered through multiple routes.This review details the mechanisms of action of TA in treatment of melasma and assesses the efficacy and safety associated with different administrations,which can contribute to selecting appropriate melasma treatment plan for different patients.
基金the National Natural Science Foundation of China(No.22105215)Ningbo Yongjiang Talent Introduction Programme(No.2022A-198-G),and Ningbo Natural Science Foundation(No.2024J006)+3 种基金the Zhejiang Provincial Natural Science Foundation of China(No.LQ23H180001)the support from the National Natural Science Foundation of China(No.22107104)Ningbo Natural Science Foundation(No.2023J066)the National Natural Science Foundation of China(No.22175035).
文摘Aromatic ketones,such as 9-fluorenone(9-FO),are known for their high intersystem crossing quantum yields(Φ_(ISC)≈1),rendering them highly valuable for photochemical reactions and dye-sensitized solar cells.However,their use as photosensitizers in biological contexts has been hindered by their low extinction coefficients,high excitation energies,and weak fluorescence.To address these limitations,we conjugated 9-FO with a fused-ring electron donor,resulting in an acceptor-donor-acceptor derivative IDT-9F.This strategy has successfully redshifted the absorption peak of 9-FO(380 nm)into the visible light range(498 nm)and significantly enhanced its light absorption capability(~310-fold)and fluorescence quantum yield(~100-fold).Furthermore,IDT-9F was encapsulated within pH-responsive nanoparticles using an acid-induced charge-reversal polymer as the amphiphilic matrix,and enabled fluorescence imaging-guided photodynamic inactivation of Gram-positive bacteria in acidic environment with a remarkable bacterial inhibition rate exceeding 99.9%.
基金supports from National Natural Science Foundation of China(No.52322401)Project of Basic Science Center of National Natural Science Foundation(No.52288101)Open Fund of the State Key Laboratory of Offshore Oil Effi cient Exploitation(No.CCL2024RCPS0170RSN).
文摘Phase-change material(PCM)has a high potential to cool the drilling fluids for ultra-deep oil/gas wells and geothermal wells to ensure efficient drilling and resource exploitation.Because PCM tends to agglomerate and seriously affect the properties of drilling fluid,it is necessary that the PCM is protected by a shell on its surface.In this study,a novel microencapsulated PCM(with a phase transition temperature of 130.5℃)with a SiO_(2) protection shell were obtained by using tetraethyl orthosilicate(TEOS)as silicon source via a sol-gel process.PCM microcapsules with optimal synthesis ratio of 3:4 have excellent warm blood characteristics and smooth shell.The addition of 5 wt%PCM microcapsules for accurate heat trapping and temperature control at 130℃ effectively delays the time of drilling fluid reaching 150℃ by 42.5%,which improves the operability of drilling fluid at high cycle temperature.The results of this study can provide useful insights and information for use of PCM in ultra-deep oil/gas and geothermal wells.
基金supports from the Major Program of National Natural Science Foundation of China(No.51991361)National Natural Science Foundation of China(No.U1762212,No.52074329)+1 种基金Program for Changjiang Scholars and Innovative Research Team in University(IRT_14R58)Innovative Project of China University of Petroleum YCX2019013.
文摘The incorporation of fibers represents a crucial technique for improving the mechanical properties and other relevant characteristics of cement-based composites(CBC),including concrete,cement mortar,and oil-well cement.Especially,carbon fiber(CF)has a great potential for reinforcing oil-well cement due to its high strength,modulus,stiffness,high temperature,corrosion and fatigue resistance as well as chemical stability.There is a huge amount of waste CFs all over the world which show better performance in cement industry,while their reuse will realize waste recovery(good environment impact)and greatly reduce cost.This review paper presents the recent progress of using CF in enhancing mechanical properties of CBC.We put high emphasis on the CF surface modification for reinforcing bond strength at the cement/CF interface.Comprehensive discussion with respect to effects of CF and modified CF on CBC properties is performed.The key properties of CBC examined in this study encompass mechanical characteristics(compressive strength,flexural strength,and tensile strength),dimensional stability(shrinkage behavior),durability indicators(water absorption and permeability),and fracture-related properties(toughness,crack resistance,and impact performance).Thus,suggestions are given for the future study and application of CF in oil-well cement.
基金Domestic support from the Foundation of Science&Technology Department of Sichuan Province(Nos.2020YJ0212 and 2023YFS0060)1.3.5 project for disciplines of excellence,West China Hospital,Sichuan University(No.ZYJC21006)
文摘Background:The results of studies comparing Billroth-I(B-I)with Roux-en-Y(R-Y)reconstruction on the quality of life(QoL)are still inconsistent.The aim of this trial was to compare the long-term QoL of B-I with R-Y anastomosis after curative distal gastrectomy for gastric cancer.Methods:A total of 140 patients undergoing curative distal gastrectomy with D2 lymphadenectomy in West China Hospital,Sichuan University from May 2011 to May 2014 were randomly assigned to the B-I group(N=70)and R-Y group(N=70).The follow-up time points were 1,3,6,9,12,24,36,48,and 60 months after the operation.The final follow-up time was May 2019.The clinicopathological features,operative safety,postoperative recovery,long-term survival as well as QoL were compared,among which QoL score was the primary outcome.An intention-to-treat analysis was applied.Results:The baseline characteristics were comparable between the two groups.There were no statistically significant differences in terms of postoperative morbidity and mortality rates,and postoperative recovery between the two groups.Less estimated blood loss and shorter surgical duration were found in the B-I group.There were no statistically significant differences in 5-year overall survival(79%[55/70]of the B-I group vs.80%[56/70]of the R-Y group,P=0.966)and recurrence-free survival rates(79%[55/70]of the B-I group vs.78%[55/70]of the R-Y group,P=0.979)between the two groups.The scores of the global health status of the R-Y group were higher than those of the B-I group with statistically significant differences(postoperative 1 year:85.4±13.1 vs.88.8±16.1,P=0.033;postoperative 3 year:87.3±15.2 vs.92.8±11.3,P=0.028;postoperative 5 year:90.9±13.7 vs.96.4±5.6,P=0.010),and the reflux(postoperative 3 year:8.8±12.9 vs.2.8±5.3,P=0.001;postoperative 5 year:5.1±9.8 vs.1.8±4.7,P=0.033)and epigastric pain(postoperative 1 year:11.8±12.7 vs.6.1±8.8,P=0.008;postoperative 3 year:9.4±10.6 vs.4.6±7.9,P=0.006;postoperative 5 year:6.0±8.9 vs.2.7±4.6,P=0.022)were milder in the R-Y group than those of the B-I group at the postoperative 1,3,and 5-year time points.Conclusions:Compared with B-I group,R-Y reconstruction was associated with better long-term QoL by reducing reflux and epigastric pain,without changing survival outcomes.Trial Registration:ChiCTR.org.cn,ChiCTR-TRC-10001434.
文摘In order to solve the problem of poor thermal insulation in the current wood-plastic building,two kinds of structural wood wall integrated with wood plastic composite(WPC)are designed,and the thermal insulation performances of the walls are studied.The results show that the WPC integrated wall with frame-shear structure has a good stability,and the excellent performance of the WPC can be fully realized.Wall studs and wall panels are important factors affecting the thermal performance of the walls.Wood plastic materials can meet the thermal performance requirements of the walls.The single-layer frame walls and double-layer frame walls integrated with the WPC both have a good thermal performance.According to‘Design Standard for Energy Efficiency of Public Buildings(GB 50189-2015)’,the heat transfer coefficient of the single-layer frame wall integrated with 20 mm thick WPC wall boards and WPC wall studs is 0.414 W/(m^(2)•K),which can meet the standard of wall thermal levelⅡt and is suitable for cold areas.The heat transfer coefficient of the double-layer frame wall integrated with 50 mm thick WPC wall panel and WPC wall studs is 0.207 W/(m^(2)•K),which can meet the standard of wall thermal levelⅠt and is suitable for severe cold areas.
基金This work was supported by the Strategic Priority Science and Technology Program(XDA24020101,XDPB1801)the Key Research Program of Frontier Sciences(ZDBS-LY-SM014)+1 种基金the Shenzhen Grants(JCYJ20180507182241844)the Biological Resources Program(KFJ-BRP-017-58)from the Chinese Academy of Sciences.
文摘The development of base editing(BE)technology has opened a new avenue for research studies in bacteriology,particularly for bacterial species in which the DNA double-strand breaks(DSBs)introduced by CRISPR/Cas system would lead to cell death.However,a major limitation of BE-mediated gene editing is the restricted editable sites in the target bacterial genome due to highly diverse genomic compositions,such as GC content.Herein,we developed a broad-spectrum DNase-inactive Cpf1(dCpf1)variant from Francisella novicida(bsdFnCpf1)through directed evolution.The resulting optimized mutant showed a substantially expanded targeting range,including previously non-canonical protospacer-adjacent motifs(PAMs),especially the GC-rich PAMs.Cytidine deaminase APOBEC1 and uracil DNA glycosylase inhibitor(UGI)were fused with bsdFnCpf1 to achieve specific C to T mutations at multiple target sites with canonical or non-canonical PAMs in the E.coli genome without compromising cell growth.We anticipate that bsdFnCpf1 could be applied for multiplex gene regulation and BE in species that have been reported to be suitable for Cpf1.