Triple-negative breast cancer(TNBC)is a subtype of breast cancer in which the estrogen receptor and progesterone receptor are not expressed,and human epidermal growth factor receptor 2 is not amplified or overexpresse...Triple-negative breast cancer(TNBC)is a subtype of breast cancer in which the estrogen receptor and progesterone receptor are not expressed,and human epidermal growth factor receptor 2 is not amplified or overexpressed either,which make the clinical diagnosis and treatment very challenging.Molecular imaging can provide an effective way to diagnose TNBC.Upconversion nanoparticles(UCNPs),are a promising new generation of molecular imaging probes.However,UCNPs still need to be improved for tumor-targeting ability and biocompatibility.This study describes a novel probe based on cancer cell membrane-coated upconversion nanoparticles(CCm-UCNPs),owing to the low immunogenicity and homologous-targeting ability of cancer cell membranes,and modified multifunctional UCNPs.This probe exhibits excellent performance in breast cancer molecular classification and TNBC diagnosis through UCL/MRI/PET tri-modality imaging in vivo.By using this probe,MDA-MB-231 was successfully differentiated between MCF-7 tumor models in vivo.Based on the tumor imaging and molecular classification results,the probe is also expected to be modified for drug delivery in the future,contributing to the treatment of TNBC.The combination of nanoparticles with biomimetic cell membranes has the potential for multiple clinical applications.展开更多
Objectives:The study was conducted to make a bibliometric analysis of published literature in order to assess the research status of nurse turnover in China.Methods:We obtained 239 papers from two major electronic dat...Objectives:The study was conducted to make a bibliometric analysis of published literature in order to assess the research status of nurse turnover in China.Methods:We obtained 239 papers from two major electronic databases,CNKI and Wanfang from 2000 to 2015(updated to 31st,December).Articles in languages other than Chinese were excluded.The keywords used were‘nurses’or‘nursing staff’and‘leave’or‘intend to leave’.Results:A total of 239 articles met the inclusion criteria,including 33 masters'dissertations and 206 journal articles.206 articles were published in twenty-five kinds of journals in China.Nursing journals had the biggest share,about(88%,181/206).82%(196/239)articles are quantitative research.239 articles come from 26 different provinces,cities or autonomous regions.The top ten regions which have the largest number of publications are Beijing,Shandong,Shanghai,Guangdong,Heilongjiang,Jiangsu,Hunan,Zhejiang,Hubei,Liaoning provinces.The coauthored articles account for 75%of all the publications.Only a small fraction of research works has obtained fundings.Conclusion:Further studies are greatly needed on the development of sound measures to tackle nurse turnover and shortage.The following improvements should be made,such as strengthening nursing researcher'consciousness and capability and increasing nursing fundings in China.展开更多
Colorectal cancer is often accompanied by multiple organ metastasis.Anaerobic Bifidobacterium Infantis(BI)bacterial can selectively grow in hypoxic colorectal tumor microenvironment(TME),to own the natural advantage o...Colorectal cancer is often accompanied by multiple organ metastasis.Anaerobic Bifidobacterium Infantis(BI)bacterial can selectively grow in hypoxic colorectal tumor microenvironment(TME),to own the natural advantage of preferentially colorectal tumor targeting.Herein,a self-guidance biological hybrid drug delivery system(BI-ES-Fe Alg/DOX)based on BI was constructed to inhibit the proliferation and metastasis of colon cancer.Results demonstrated that BI-ES-Fe Alg/DOX could overcome physical barriers to target and accumulate in colon tumor tissues.Then DOX was released to kill tumor cells along with the phase transition(solid to liquid)of Fe Alg hydrogel,due to Fe3+was reduced to Fe^(2+)by intracellular GSH.Meanwhile,BI-ES selectively colonized into tumors and expressed endostatin(ES)protein to down-regulate VEGF and b FGF expression,exerting anti-angiogenic effect.Moreover,Fe Alg catalyzed H_(2)O_(2)in the local tumor to generate cytotoxic·OH,further enhancing the antitumor effect.The pharmacodynamic result in AOM/DSS model proved that BI-ES-Fe Alg/DOX had the best therapeutic effect,with the final V/V0of 2.19±0.57,which was significantly lower than the other groups.Meanwhile,on CT-26tumor-bearing model,it also showed an outstanding anti-tumor effect with inhibition rate of 82.12%±3.08%.In addition,lung metastases decreased significantly in tumor metastasis model after BI-ES-Fe Alg/DOX treatment.展开更多
The effect of the baicalin,a bio-active flavonoid extracted from Scutellaria baicalensis Georgi,on the carbon tetrachloride(CCl_(4))induced liver fibrosis was investigated.To compare the effect of baicalin on the live...The effect of the baicalin,a bio-active flavonoid extracted from Scutellaria baicalensis Georgi,on the carbon tetrachloride(CCl_(4))induced liver fibrosis was investigated.To compare the effect of baicalin on the liver fibrosis,five different groups of rats treated by 100,200,and 400 mg/kg baicalin were studied.Upon CCl_(4) treatment,the levels of procollagen type III,aspartate aminotransferase,aminotransferase,hyaluronic acid,and hydroxyproline were significantly increased,whereas the superoxide dismutase and glutathione peroxidase content were decreased.These changes in the biochemical parameters,which are associated with liver function,were significantly attenuated by the baicalin treatment,suggesting that baicalin can suppress the liver fibrosis induced by CCl_(4).Moreover,the histological staining analysis demonstrated that baicalin could effectively inhibit the degree of liver cell injury.The protein expression of AKT/JAK2/ERK in the serum were markedly increased by CCl_(4) but suppressed by the treatment of baicalin in a dose-dependent manner,implying that baicalin can attenuated cell apoptosis induced by CCl_(4).Overall,these results suggest that baicalin effectively protects hepatocytes from the CCl_(4) oxidative damage,likely due to the inhibition of free radical generation and cell apoptosis during the liver injury.展开更多
Clostridium acetobutylicum has been extensively exploited to produce biofuels and solvents and its biofilm could dramatically improve the productivities.However,genetic control of C.acetobutylicum biofilm has not been...Clostridium acetobutylicum has been extensively exploited to produce biofuels and solvents and its biofilm could dramatically improve the productivities.However,genetic control of C.acetobutylicum biofilm has not been dissected so far.Here,to identify potential genes controlling C.acetobutylicum biofilm formation,over 40 gene candidates associated with extracellular matrix,cell surface,cell signaling or gene transcription,were tried to be disrupted to examine their individual impact.A total of 25 disruptants were finally obtained over years of attempts,for which biofilm and relevant phenotypes were characterized.Most of these disruptants formed robust biofilm still,or suffered both growth and biofilm defect.Only a strain with a disrupted histidine kinase gene(CA_C2730,designated bfcK in this study)abolished biofilm formation without impairing cell growth or solvent production.Further analysis revealed that bfcK could control flagellar biogenesis and cell motility at protein levels.The bfcK also appeared to repress the phosphorylation of a serine/threonine protein kinase(encoded by CA_C0404)that might negatively regulate biofilm formation.Based on these findings,possible bfcK-mediated mechanisms for biofilm formation were proposed.This is a big step toward understanding the biofilm formation in C.acetobutylicum and will help further engineering of its biofilm-based industrial processes.展开更多
Regional integrated energy system(RIES)cluster,i.e.,multi-source integration and multi-region coordination,is an effective approach for increasing energy utilization efficiency.The hierarchical architecture and limite...Regional integrated energy system(RIES)cluster,i.e.,multi-source integration and multi-region coordination,is an effective approach for increasing energy utilization efficiency.The hierarchical architecture and limited information sharing of RIES cluster make it difficult for traditional game theory to accurately describe their game behavior.Thus,a hierarchical game approach considering bounded rationality is proposed in this paper to balance the interests of optimizing RIES cluster under privacy protection.A Stackelberg game with the cluster operator(CO)as the leader and multiple RIES as followers is developed to simultaneously optimize leader benefit and RIES utilization efficiency.Concurrently,a slight altruistic function is introduced to simulate the game behavior of each RIES agent on whether to cooperate or not.By introducing an evolutionary game based on bounded rationality in the lower layer,the flaw of the assumption that participants are completely rational can be avoided.Specially,for autonomous optimal dispatching,each RIES is treated as a prosumer,fexibly switching its market participation role to achieve cluster coordination optimization.Case studies on a RIES cluster verify effectiveness of the proposed approach.展开更多
Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'...Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'turnover intention were conducted in Jiangsu Province.This study mainly aims to examine the level and factors that influence nurses to leave their work in Jiangsu Province of Eastern China.Methods:A cross-sectional survey of 1978 nurses was conducted at 48 hospitals in 14 key cities throughout Jiangsu Province.The turnover intention in nurses was measured by the scale of intent to leave the profession.The work environment of nurses was measured by the Chinese version of the Practice Environment Scale.A multiple linear regression model was applied to analyse the factors associated with turnover intention.Results:The resignation rate of nurses in the hospitals of Jiangsu Province ranged from 0.64%to 12.71%in 2016.The mean scores were 15.50±3.44 for turnover intention,and 3.06±0.51 for work environment.Involvement in hospital affairs,resource adequacy,age,professional title,year(s)working,employment type and education level were the predictors of nurse intent to leave(P<0.05).Conclusion:The work environment of nurses in hospitals must be improved in staffing and resource and nurses'involvement in hospital affairs.The current study corroborates that nurses have high turnover intention.Thus,effective measures are needed to improve nurse accomplishment,professional status,participation in hospital affairs and career planning to reduce their turnover intention.展开更多
As one of the most important ways to reduce the greenhouse gas emission,carbon dioxide（CO2）enhanced gas recovery（CO2-EGR） is attractive since the gas recovery can be enhanced simultaneously with CO2sequestration.B...As one of the most important ways to reduce the greenhouse gas emission,carbon dioxide（CO2）enhanced gas recovery（CO2-EGR） is attractive since the gas recovery can be enhanced simultaneously with CO2sequestration.Based on the existing equation of state（EOS） module of TOUGH2 MP,extEOS7C is developed to calculate the phase partition of H2O-CO2-CH4-NaCl mixtures accurately with consideration of dissolved NaCI and brine properties at high pressure and temperature conditions.Verifications show that it can be applied up to the pressure of 100 MPa and temperature of 150℃.The module was implemented in the linked simulator TOUGH2MP-FLAC3 D for the coupled hydro-mechanical simulations.A simplified three-dimensional（3D）1/4 model（2.2 km×1 km×1 km） which consists of the whole reservoir,caprock and baserock was generated based on the geological conditions of a gas field in the North German Basin.The simulation results show that,under an injection rate of 200,000 t/yr and production rate of 200,000 sm3/d,CO2breakthrough occurred in the case with the initial reservoir pressure of 5 MPa but did not occur in the case of 42 MPa.Under low pressure conditions,the pressure driven horizontal transport is the dominant process;while under high pressure conditions,the density driven vertical flow is dominant.Under the considered conditions,the CO2-EGR caused only small pressure changes.The largest pore pressure increase（2 MPa） and uplift（7 mm） occurred at the caprock bottom induced by only CO2injection.The caprock had still the primary stress state and its integrity was not affected.The formation water salinity and temperature variations of ±20℃ had small influences on the CO2-EGR process.In order to slow down the breakthrough,it is suggested that CO2-EGR should be carried out before the reservoir pressure drops below the critical pressure of CO2.展开更多
The salinization of irrigated land affects agricultural productivity.HIGH-AFFINITY POTASSIUM(K+)TRANSPORTER 1;5(OsHKT1;5)-dependent sodium(Na+)transport is a key salt tolerance mechanism during rice growth and develop...The salinization of irrigated land affects agricultural productivity.HIGH-AFFINITY POTASSIUM(K+)TRANSPORTER 1;5(OsHKT1;5)-dependent sodium(Na+)transport is a key salt tolerance mechanism during rice growth and development.Using a previously generated high-throughput activation tagging-based T-DNA insertion mutant pool,we isolated a mutant exhibiting salt stress-sensitive phenotype,caused by a reduction in OsHKT1;5transcripts.The salt stress-sensitive phenotype of this mutant results from the loss of function of OsDNAJ15,which encodes plasma membranelocalized heat shock protein 40(Hsp40).osdnaj15loss-of-function mutants show decreased plant height,increased leaf angle,and reduced grain number caused by shorter panicle length and fewer branches.On the other háand,OsDNAJ15-overexpression plants showed salt stress-tolerant phenotypes.Intriguingly,salt stress facilitates the nuclear relocation of OsDNAJ15 so that it can interact with OsBAG4,and OsDNAJ15 and OsBAG4synergistically facilitate the DNA-binding activity of OsMYB106 to positively regulate the expression of OsHKT1;5.Overall,our results reveal a novel function of plasma membrane-localized Hsp40protein in modulating,alongside chaperon regulator OsBAG4,transcriptional regulation under salinity stress tolerance.展开更多
Acute kidney injury(AKI)leads to unacceptably high mortality due to difficulties in timely intervention and less efficient renal delivery of therapeutic drugs.Here,a series of polyvinylpyrrolidone(PVP)-curcumin nanopa...Acute kidney injury(AKI)leads to unacceptably high mortality due to difficulties in timely intervention and less efficient renal delivery of therapeutic drugs.Here,a series of polyvinylpyrrolidone(PVP)-curcumin nanoparticles(PCurNP)are designed to meet the renal excretion threshold(~45 kDa),presenting a controllable delivery nanosystem for kidney targeting.Renal accumulation of the relatively small nanoparticles,^(89)Zr-PCurNP M10 with the diameter between 5 and 8 nm,is found to be 1.7 times and 1.8 times higher than the accumulation of^(89)Zr-PCurNP M29(20-50 nm)and M40(20-50 nm)as revealed by PET imaging.Furthermore,serum creatinine analysis,kidney tissues histology,and tubular injury scores revealed that PCurNP M10 efficiently treated cisplatin-induced AKI.Herein,PCurNP offers a novel and simple strategy for precise PET image-guided drug delivery of renal protective materials.展开更多
The BCR-ABL1 fusion gene is a driver and hallmark of leukemia and a classic structural variant.1 Single nucleotide variations(SNVs)occurring in the ABL1gene kinase domain(KD)and aberrant DNA methylation modifications,...The BCR-ABL1 fusion gene is a driver and hallmark of leukemia and a classic structural variant.1 Single nucleotide variations(SNVs)occurring in the ABL1gene kinase domain(KD)and aberrant DNA methylation modifications,specifically 5-methylcytosine(5mC)of the BCR gene promoter,3 have strong clinical implications,such as tyrosine kinase inhibitor resistance,therapeutic responsiveness,and disease progression.展开更多
The glucose sensor HEXOKINASE1(HXK1)integrates myriad external and internal signals to regulate gene expression and development in Arabidopsis thaliana.However,how HXK1 mediates glucose signaling in the nucleus remain...The glucose sensor HEXOKINASE1(HXK1)integrates myriad external and internal signals to regulate gene expression and development in Arabidopsis thaliana.However,how HXK1 mediates glucose signaling in the nucleus remains unclear.Here,using immunoprecipitationcoupled mass spectrometry,we show that two catalytic subunits of Polycomb Repressive Complex 2,SWINGER(SWN)and CURLY LEAF(CLF),directly interact with catalytically active HXK1 and its inactive forms(HXK1^(G104D) and HXK1^(S177A))via their evolutionarily conserved SANT domains.HXK1,CLF,and SWN target common glucose-responsive genes to regulate glucose signaling,as revealed by RNA sequencing.The glucose-insensitive phenotypes of the Arabidopsis swn-1 and clf-50 mutants were similar to that of hxk1,and genetic analysis revealed that CLF,SWN,and HXK1 function in the same genetic pathway.Intriguingly,HXK1 is required for CLF-and SWN-mediated histone H3 lysine 27(H3K27me3)deposition and glucose-mediated gene repression.Moreover,CLF and SWN affect the recruitment of HXK1 to its target chromatin.These findings support a model in which HXK1 and epigenetic modifiers form a nuclear complex to cooperatively mediate glucose signaling,thereby affecting the histone modification and expression of glucoseregulated genes in plants.展开更多
Due to space limitation,mutual coupling occurs almost invisibly in array antennas.In this paper,the mutual coupling effects on the two most popular categories of array antennas,i.e.,phased arrays and multiple-input mu...Due to space limitation,mutual coupling occurs almost invisibly in array antennas.In this paper,the mutual coupling effects on the two most popular categories of array antennas,i.e.,phased arrays and multiple-input multiple-output(MIMO)antennas,are reviewed.Some misconceptions regarding the mutual coupling effects are uncovered.It is shown that the steering pattern of a phased array at an arbitrary scan-ning angle can be readily calculated once the embedded radiation patterns of the array elements(including the mutual coupling effect)are obtained.As antenna spacing decreases,absorption loss increases,yet the phase terms tend to add up constructively as antenna spacing reduces,which may overcompensate the absorption loss due to mutual coupling.Thus,the array efficiency may be increased by reducing the antenna spacing.A patch antenna array is used to illustrate this phenomenon.It is further shown that while mutual coupling tends to reduce the correlation of two-element arrays,it has a negligible effect on the overall correlations of larger arrays.Finally,various mutual coupling reduction techniques are briefly presented.Two feasible techniques for large planar arrays are used to illustrate the benefits of array decoupling.展开更多
The grid load attributable to electric vehicles (EVs)is affected by the choice behaviors of EV users. To analyze theeffects of factors such as travel demand and electricity priceson user behavior, a logit discrete cho...The grid load attributable to electric vehicles (EVs)is affected by the choice behaviors of EV users. To analyze theeffects of factors such as travel demand and electricity priceson user behavior, a logit discrete choice model is introducedto simulate the users decisions to charge/travel. Based on aquasi-steady-state traffic network, a model for cluster electricvehicles considering the user’s behavior is designed to obtain theprobability distribution of the user’s behavior and the chargeand discharge curves of cluster EVs under various scenarios. Thevalidity of the proposed model is verified using an IEEE 9-nodetraffic network case and an urban traffic network case. Furthermore,the impact of the electricity price, traffic conditions, andother factors on the load curves of urban EVs is analyzed.展开更多
Resolution is undoubtedly the most important parameter in optical microscopy by providing an estimation on the maximum resolving power of a certain optical microscope. For centuries, the resolution of an optical micro...Resolution is undoubtedly the most important parameter in optical microscopy by providing an estimation on the maximum resolving power of a certain optical microscope. For centuries, the resolution of an optical microscope is generally considered to be limited only by the numerical aperture of the optical system and the wavelength of light. However, since the invention and popularity of various advanced fluorescence microscopy techniques, especially super-resolution fluorescence microscopy, many new methods have been proposed for estimating the resolution, leading to confusions for researchers who need to quantify the resolution of their fluorescence microscopes. In this paper, we firstly summarize the early concepts and criteria for predicting the resolution limit of an ideal optical system. Then, we discuss some important influence factors that deteriorate the resolution of a certain fluorescence microscope. Finally, we provide methods and examples on how to measure the resolution of a fluorescence microscope from captured fluorescence images. This paper aims to answer as best as possible the theoretical and practical issues regarding the resolution estimation in fluorescence microscopy.展开更多
基金the National Natural Science Foundation of China(Nos.81630049 and 81501532).
文摘Triple-negative breast cancer(TNBC)is a subtype of breast cancer in which the estrogen receptor and progesterone receptor are not expressed,and human epidermal growth factor receptor 2 is not amplified or overexpressed either,which make the clinical diagnosis and treatment very challenging.Molecular imaging can provide an effective way to diagnose TNBC.Upconversion nanoparticles(UCNPs),are a promising new generation of molecular imaging probes.However,UCNPs still need to be improved for tumor-targeting ability and biocompatibility.This study describes a novel probe based on cancer cell membrane-coated upconversion nanoparticles(CCm-UCNPs),owing to the low immunogenicity and homologous-targeting ability of cancer cell membranes,and modified multifunctional UCNPs.This probe exhibits excellent performance in breast cancer molecular classification and TNBC diagnosis through UCL/MRI/PET tri-modality imaging in vivo.By using this probe,MDA-MB-231 was successfully differentiated between MCF-7 tumor models in vivo.Based on the tumor imaging and molecular classification results,the probe is also expected to be modified for drug delivery in the future,contributing to the treatment of TNBC.The combination of nanoparticles with biomimetic cell membranes has the potential for multiple clinical applications.
文摘Objectives:The study was conducted to make a bibliometric analysis of published literature in order to assess the research status of nurse turnover in China.Methods:We obtained 239 papers from two major electronic databases,CNKI and Wanfang from 2000 to 2015(updated to 31st,December).Articles in languages other than Chinese were excluded.The keywords used were‘nurses’or‘nursing staff’and‘leave’or‘intend to leave’.Results:A total of 239 articles met the inclusion criteria,including 33 masters'dissertations and 206 journal articles.206 articles were published in twenty-five kinds of journals in China.Nursing journals had the biggest share,about(88%,181/206).82%(196/239)articles are quantitative research.239 articles come from 26 different provinces,cities or autonomous regions.The top ten regions which have the largest number of publications are Beijing,Shandong,Shanghai,Guangdong,Heilongjiang,Jiangsu,Hunan,Zhejiang,Hubei,Liaoning provinces.The coauthored articles account for 75%of all the publications.Only a small fraction of research works has obtained fundings.Conclusion:Further studies are greatly needed on the development of sound measures to tackle nurse turnover and shortage.The following improvements should be made,such as strengthening nursing researcher'consciousness and capability and increasing nursing fundings in China.
基金supported by National Natural Science Foundation of China(82102918)Youth Talent Promotion Project in Henan Province(2020HYTP011)。
文摘Colorectal cancer is often accompanied by multiple organ metastasis.Anaerobic Bifidobacterium Infantis(BI)bacterial can selectively grow in hypoxic colorectal tumor microenvironment(TME),to own the natural advantage of preferentially colorectal tumor targeting.Herein,a self-guidance biological hybrid drug delivery system(BI-ES-Fe Alg/DOX)based on BI was constructed to inhibit the proliferation and metastasis of colon cancer.Results demonstrated that BI-ES-Fe Alg/DOX could overcome physical barriers to target and accumulate in colon tumor tissues.Then DOX was released to kill tumor cells along with the phase transition(solid to liquid)of Fe Alg hydrogel,due to Fe3+was reduced to Fe^(2+)by intracellular GSH.Meanwhile,BI-ES selectively colonized into tumors and expressed endostatin(ES)protein to down-regulate VEGF and b FGF expression,exerting anti-angiogenic effect.Moreover,Fe Alg catalyzed H_(2)O_(2)in the local tumor to generate cytotoxic·OH,further enhancing the antitumor effect.The pharmacodynamic result in AOM/DSS model proved that BI-ES-Fe Alg/DOX had the best therapeutic effect,with the final V/V0of 2.19±0.57,which was significantly lower than the other groups.Meanwhile,on CT-26tumor-bearing model,it also showed an outstanding anti-tumor effect with inhibition rate of 82.12%±3.08%.In addition,lung metastases decreased significantly in tumor metastasis model after BI-ES-Fe Alg/DOX treatment.
基金The animal study was approved by the Institutional Animal Care and Use Committee of Shanghai Rat&Mouse Biotech Co.,Ltd.(SHRM)(Approval No.SHRM-IACUC-045).
文摘The effect of the baicalin,a bio-active flavonoid extracted from Scutellaria baicalensis Georgi,on the carbon tetrachloride(CCl_(4))induced liver fibrosis was investigated.To compare the effect of baicalin on the liver fibrosis,five different groups of rats treated by 100,200,and 400 mg/kg baicalin were studied.Upon CCl_(4) treatment,the levels of procollagen type III,aspartate aminotransferase,aminotransferase,hyaluronic acid,and hydroxyproline were significantly increased,whereas the superoxide dismutase and glutathione peroxidase content were decreased.These changes in the biochemical parameters,which are associated with liver function,were significantly attenuated by the baicalin treatment,suggesting that baicalin can suppress the liver fibrosis induced by CCl_(4).Moreover,the histological staining analysis demonstrated that baicalin could effectively inhibit the degree of liver cell injury.The protein expression of AKT/JAK2/ERK in the serum were markedly increased by CCl_(4) but suppressed by the treatment of baicalin in a dose-dependent manner,implying that baicalin can attenuated cell apoptosis induced by CCl_(4).Overall,these results suggest that baicalin effectively protects hepatocytes from the CCl_(4) oxidative damage,likely due to the inhibition of free radical generation and cell apoptosis during the liver injury.
基金This work was supported by the Key Program of the National Natural Science Foundation of China(Grant No.21636003)the Outstanding Youth Foundation of Jiangsu(Grant No.SBK2017010373)+1 种基金the National Key Research and Development Program of China(Grant No.2019YFD1101204)the Jiangsu Synergetic Innovation Center for Advanced Bio-Manufacture.Dong Liu is supported by the Jiangsu Qinglan Talent Program.
文摘Clostridium acetobutylicum has been extensively exploited to produce biofuels and solvents and its biofilm could dramatically improve the productivities.However,genetic control of C.acetobutylicum biofilm has not been dissected so far.Here,to identify potential genes controlling C.acetobutylicum biofilm formation,over 40 gene candidates associated with extracellular matrix,cell surface,cell signaling or gene transcription,were tried to be disrupted to examine their individual impact.A total of 25 disruptants were finally obtained over years of attempts,for which biofilm and relevant phenotypes were characterized.Most of these disruptants formed robust biofilm still,or suffered both growth and biofilm defect.Only a strain with a disrupted histidine kinase gene(CA_C2730,designated bfcK in this study)abolished biofilm formation without impairing cell growth or solvent production.Further analysis revealed that bfcK could control flagellar biogenesis and cell motility at protein levels.The bfcK also appeared to repress the phosphorylation of a serine/threonine protein kinase(encoded by CA_C0404)that might negatively regulate biofilm formation.Based on these findings,possible bfcK-mediated mechanisms for biofilm formation were proposed.This is a big step toward understanding the biofilm formation in C.acetobutylicum and will help further engineering of its biofilm-based industrial processes.
基金supported by the National Key R&D Program(No.2020YFB0905900)the National Natural Science Foundation of China(No.52277098)。
文摘Regional integrated energy system(RIES)cluster,i.e.,multi-source integration and multi-region coordination,is an effective approach for increasing energy utilization efficiency.The hierarchical architecture and limited information sharing of RIES cluster make it difficult for traditional game theory to accurately describe their game behavior.Thus,a hierarchical game approach considering bounded rationality is proposed in this paper to balance the interests of optimizing RIES cluster under privacy protection.A Stackelberg game with the cluster operator(CO)as the leader and multiple RIES as followers is developed to simultaneously optimize leader benefit and RIES utilization efficiency.Concurrently,a slight altruistic function is introduced to simulate the game behavior of each RIES agent on whether to cooperate or not.By introducing an evolutionary game based on bounded rationality in the lower layer,the flaw of the assumption that participants are completely rational can be avoided.Specially,for autonomous optimal dispatching,each RIES is treated as a prosumer,fexibly switching its market participation role to achieve cluster coordination optimization.Case studies on a RIES cluster verify effectiveness of the proposed approach.
基金This study was supported by the Jiangsu Provincial Health and Family Planning Commission(WSGL201605)
文摘Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'turnover intention were conducted in Jiangsu Province.This study mainly aims to examine the level and factors that influence nurses to leave their work in Jiangsu Province of Eastern China.Methods:A cross-sectional survey of 1978 nurses was conducted at 48 hospitals in 14 key cities throughout Jiangsu Province.The turnover intention in nurses was measured by the scale of intent to leave the profession.The work environment of nurses was measured by the Chinese version of the Practice Environment Scale.A multiple linear regression model was applied to analyse the factors associated with turnover intention.Results:The resignation rate of nurses in the hospitals of Jiangsu Province ranged from 0.64%to 12.71%in 2016.The mean scores were 15.50±3.44 for turnover intention,and 3.06±0.51 for work environment.Involvement in hospital affairs,resource adequacy,age,professional title,year(s)working,employment type and education level were the predictors of nurse intent to leave(P<0.05).Conclusion:The work environment of nurses in hospitals must be improved in staffing and resource and nurses'involvement in hospital affairs.The current study corroborates that nurses have high turnover intention.Thus,effective measures are needed to improve nurse accomplishment,professional status,participation in hospital affairs and career planning to reduce their turnover intention.
基金funded by the National Natural Science Foundation of China(Grant No.NSFC51374147)the German Society for Petroleum and Coal Science and Technology(Grant No.DGMK680-4)
文摘As one of the most important ways to reduce the greenhouse gas emission,carbon dioxide（CO2）enhanced gas recovery（CO2-EGR） is attractive since the gas recovery can be enhanced simultaneously with CO2sequestration.Based on the existing equation of state（EOS） module of TOUGH2 MP,extEOS7C is developed to calculate the phase partition of H2O-CO2-CH4-NaCl mixtures accurately with consideration of dissolved NaCI and brine properties at high pressure and temperature conditions.Verifications show that it can be applied up to the pressure of 100 MPa and temperature of 150℃.The module was implemented in the linked simulator TOUGH2MP-FLAC3 D for the coupled hydro-mechanical simulations.A simplified three-dimensional（3D）1/4 model（2.2 km×1 km×1 km） which consists of the whole reservoir,caprock and baserock was generated based on the geological conditions of a gas field in the North German Basin.The simulation results show that,under an injection rate of 200,000 t/yr and production rate of 200,000 sm3/d,CO2breakthrough occurred in the case with the initial reservoir pressure of 5 MPa but did not occur in the case of 42 MPa.Under low pressure conditions,the pressure driven horizontal transport is the dominant process;while under high pressure conditions,the density driven vertical flow is dominant.Under the considered conditions,the CO2-EGR caused only small pressure changes.The largest pore pressure increase（2 MPa） and uplift（7 mm） occurred at the caprock bottom induced by only CO2injection.The caprock had still the primary stress state and its integrity was not affected.The formation water salinity and temperature variations of ±20℃ had small influences on the CO2-EGR process.In order to slow down the breakthrough,it is suggested that CO2-EGR should be carried out before the reservoir pressure drops below the critical pressure of CO2.
基金supported by the National Natural Science Foundation of China (32001448,32272027,and 31971822)China Postdoctoral Science Foundation (2020M670828)Young Elite Scientists Sponsorship Program by Jilin Association for Science and Technology (QT2020011)。
文摘The salinization of irrigated land affects agricultural productivity.HIGH-AFFINITY POTASSIUM(K+)TRANSPORTER 1;5(OsHKT1;5)-dependent sodium(Na+)transport is a key salt tolerance mechanism during rice growth and development.Using a previously generated high-throughput activation tagging-based T-DNA insertion mutant pool,we isolated a mutant exhibiting salt stress-sensitive phenotype,caused by a reduction in OsHKT1;5transcripts.The salt stress-sensitive phenotype of this mutant results from the loss of function of OsDNAJ15,which encodes plasma membranelocalized heat shock protein 40(Hsp40).osdnaj15loss-of-function mutants show decreased plant height,increased leaf angle,and reduced grain number caused by shorter panicle length and fewer branches.On the other háand,OsDNAJ15-overexpression plants showed salt stress-tolerant phenotypes.Intriguingly,salt stress facilitates the nuclear relocation of OsDNAJ15 so that it can interact with OsBAG4,and OsDNAJ15 and OsBAG4synergistically facilitate the DNA-binding activity of OsMYB106 to positively regulate the expression of OsHKT1;5.Overall,our results reveal a novel function of plasma membrane-localized Hsp40protein in modulating,alongside chaperon regulator OsBAG4,transcriptional regulation under salinity stress tolerance.
基金supported by the National Natural Science Foundation of China(81601605,21571147,82102121)the Postdoctoral Science Foundation of China(2016M600670)+2 种基金supported by the University of Wisconsin–Madison,the National Institutes of Health(NIBIB/NCI P30CA014520)the Natural Science Foundation of SZU(Grant No.827-000143)the Shenzhen Peacock Plan(KQTD2016053112051497).
文摘Acute kidney injury(AKI)leads to unacceptably high mortality due to difficulties in timely intervention and less efficient renal delivery of therapeutic drugs.Here,a series of polyvinylpyrrolidone(PVP)-curcumin nanoparticles(PCurNP)are designed to meet the renal excretion threshold(~45 kDa),presenting a controllable delivery nanosystem for kidney targeting.Renal accumulation of the relatively small nanoparticles,^(89)Zr-PCurNP M10 with the diameter between 5 and 8 nm,is found to be 1.7 times and 1.8 times higher than the accumulation of^(89)Zr-PCurNP M29(20-50 nm)and M40(20-50 nm)as revealed by PET imaging.Furthermore,serum creatinine analysis,kidney tissues histology,and tubular injury scores revealed that PCurNP M10 efficiently treated cisplatin-induced AKI.Herein,PCurNP offers a novel and simple strategy for precise PET image-guided drug delivery of renal protective materials.
基金supported by the Jiangxi Province's"Double Thousand Plan"Innovation Leading Talent (China) (No.jxsq2019101060)The Youth Jinggang Scholars Program in Jiangxi Province of China,Jiangxi Natural Science Foundation (China) (No.20232BAB216017)the National Natural Science Foundation of China (No.82200653).
文摘The BCR-ABL1 fusion gene is a driver and hallmark of leukemia and a classic structural variant.1 Single nucleotide variations(SNVs)occurring in the ABL1gene kinase domain(KD)and aberrant DNA methylation modifications,specifically 5-methylcytosine(5mC)of the BCR gene promoter,3 have strong clinical implications,such as tyrosine kinase inhibitor resistance,therapeutic responsiveness,and disease progression.
基金supported by the National Natural Science Foundation of China (31971822 to Z.-Y.X. and 32001448 to Y.L.)China Postdoctoral Science Foundation (2020M670828 to Y.L.)the Fundamental Research Funds for the Central Universities (2412020QD020 to Y.L.)
文摘The glucose sensor HEXOKINASE1(HXK1)integrates myriad external and internal signals to regulate gene expression and development in Arabidopsis thaliana.However,how HXK1 mediates glucose signaling in the nucleus remains unclear.Here,using immunoprecipitationcoupled mass spectrometry,we show that two catalytic subunits of Polycomb Repressive Complex 2,SWINGER(SWN)and CURLY LEAF(CLF),directly interact with catalytically active HXK1 and its inactive forms(HXK1^(G104D) and HXK1^(S177A))via their evolutionarily conserved SANT domains.HXK1,CLF,and SWN target common glucose-responsive genes to regulate glucose signaling,as revealed by RNA sequencing.The glucose-insensitive phenotypes of the Arabidopsis swn-1 and clf-50 mutants were similar to that of hxk1,and genetic analysis revealed that CLF,SWN,and HXK1 function in the same genetic pathway.Intriguingly,HXK1 is required for CLF-and SWN-mediated histone H3 lysine 27(H3K27me3)deposition and glucose-mediated gene repression.Moreover,CLF and SWN affect the recruitment of HXK1 to its target chromatin.These findings support a model in which HXK1 and epigenetic modifiers form a nuclear complex to cooperatively mediate glucose signaling,thereby affecting the histone modification and expression of glucoseregulated genes in plants.
基金This work was supported in part by National Natural Science Foundation of China(No.61801366)Natural Science Foundation of Shaanxi Province(No.2020JM-078)Innovation Team Research Fund of Shaanxi Province(No.2019TD-013)。
文摘Due to space limitation,mutual coupling occurs almost invisibly in array antennas.In this paper,the mutual coupling effects on the two most popular categories of array antennas,i.e.,phased arrays and multiple-input multiple-output(MIMO)antennas,are reviewed.Some misconceptions regarding the mutual coupling effects are uncovered.It is shown that the steering pattern of a phased array at an arbitrary scan-ning angle can be readily calculated once the embedded radiation patterns of the array elements(including the mutual coupling effect)are obtained.As antenna spacing decreases,absorption loss increases,yet the phase terms tend to add up constructively as antenna spacing reduces,which may overcompensate the absorption loss due to mutual coupling.Thus,the array efficiency may be increased by reducing the antenna spacing.A patch antenna array is used to illustrate this phenomenon.It is further shown that while mutual coupling tends to reduce the correlation of two-element arrays,it has a negligible effect on the overall correlations of larger arrays.Finally,various mutual coupling reduction techniques are briefly presented.Two feasible techniques for large planar arrays are used to illustrate the benefits of array decoupling.
基金the National Natural Science Foundation of China (No.51777065).
文摘The grid load attributable to electric vehicles (EVs)is affected by the choice behaviors of EV users. To analyze theeffects of factors such as travel demand and electricity priceson user behavior, a logit discrete choice model is introducedto simulate the users decisions to charge/travel. Based on aquasi-steady-state traffic network, a model for cluster electricvehicles considering the user’s behavior is designed to obtain theprobability distribution of the user’s behavior and the chargeand discharge curves of cluster EVs under various scenarios. Thevalidity of the proposed model is verified using an IEEE 9-nodetraffic network case and an urban traffic network case. Furthermore,the impact of the electricity price, traffic conditions, andother factors on the load curves of urban EVs is analyzed.
基金supported by the National Natural Science Foundation of China (81427801, 81827901)National Basic Research Program of China (2015CB352003)+2 种基金Science Fund for Creative Research Groups (61721092)Fundamental Research Funds for the Central Universities (2018KFYXKJC039)Director Fund of WNLO。
文摘Resolution is undoubtedly the most important parameter in optical microscopy by providing an estimation on the maximum resolving power of a certain optical microscope. For centuries, the resolution of an optical microscope is generally considered to be limited only by the numerical aperture of the optical system and the wavelength of light. However, since the invention and popularity of various advanced fluorescence microscopy techniques, especially super-resolution fluorescence microscopy, many new methods have been proposed for estimating the resolution, leading to confusions for researchers who need to quantify the resolution of their fluorescence microscopes. In this paper, we firstly summarize the early concepts and criteria for predicting the resolution limit of an ideal optical system. Then, we discuss some important influence factors that deteriorate the resolution of a certain fluorescence microscope. Finally, we provide methods and examples on how to measure the resolution of a fluorescence microscope from captured fluorescence images. This paper aims to answer as best as possible the theoretical and practical issues regarding the resolution estimation in fluorescence microscopy.
