As one of the most effective methods to improve the accuracy and robustness of speech tasks,the audio-visual fusion approach has recently been introduced into the field of Keyword Spotting(KWS).However,existing audio-...As one of the most effective methods to improve the accuracy and robustness of speech tasks,the audio-visual fusion approach has recently been introduced into the field of Keyword Spotting(KWS).However,existing audio-visual keyword spotting models are limited to detecting isolated words,while keyword spotting for unconstrained speech is still a challenging problem.To this end,an Audio-Visual Keyword Transformer(AVKT)network is proposed to spot keywords in unconstrained video clips.The authors present a transformer classifier with learnable CLS tokens to extract distinctive keyword features from the variable-length audio and visual inputs.The outputs of audio and visual branches are combined in a decision fusion module.As humans can easily notice whether a keyword appears in a sentence or not,our AVKT network can detect whether a video clip with a spoken sentence contains a pre-specified keyword.Moreover,the position of the keyword is localised in the attention map without additional position labels.Exper-imental results on the LRS2-KWS dataset and our newly collected PKU-KWS dataset show that the accuracy of AVKT exceeded 99%in clean scenes and 85%in extremely noisy conditions.The code is available at https://github.com/jialeren/AVKT.展开更多
Lung cancer is the most prevalent cancer diagnosis and the leading cause of cancer death worldwide.Therapeutic failure in lung cancer(LUAD)is heavily influenced by drug resistance.This challenge stems from the diverse...Lung cancer is the most prevalent cancer diagnosis and the leading cause of cancer death worldwide.Therapeutic failure in lung cancer(LUAD)is heavily influenced by drug resistance.This challenge stems from the diverse cell populations within the tumor,each having unique genetic,epigenetic,and phenotypic profiles.Such variations lead to varied therapeutic responses,thereby contributing to tumor relapse and disease progression.Methods:The Genomics of Drug Sensitivity in Cancer(GDSC)database was used in this investigation to obtain the mRNA expression dataset,genomic mutation profile,and drug sensitivity information of NSCLS.Machine Learning(ML)methods,including Random Forest(RF),Artificial Neurol Network(ANN),and Support Vector Machine(SVM),were used to predict the response status of each compound based on the mRNA and mutation characteristics determined using statistical methods.The most suitable method for each drug was proposed by comparing the prediction accuracy of different ML methods,and the selected mRNA and mutation characteristics were identified as molecular features for the drug-responsive cancer subtype.Finally,the prognostic influence of molecular features on the mutational subtype of LUAD in publicly available datasets.Results:Our analyses yielded 1,564 gene features and 45 mutational features for 46 drugs.Applying the ML approach to predict the drug response for each medication revealed an upstanding performance for SVM in predicting Afuresertib drug response(area under the curve[AUC]0.875)using CIT,GAS2L3,STAG3L3,ATP2B4-mut,and IL15RA-mut as molecular features.Furthermore,the ANN algorithm using 9 mRNA characteristics demonstrated the highest prediction performance(AUC 0.780)in Gefitinib with CCL23-mut.Conclusion:This work extensively investigated the mRNA and mutation signatures associated with drug response in LUAD using a machine-learning approach and proposed a priority algorithm to predict drug response for different drugs.展开更多
A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Theref...A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Therefore, in this study, confining pressure and pull-out load are applied to grouted rockbolt systems with bond defects by a numerical simulation method, and the rockbolt is detected by ultrasonic guided waves to study the propagation law of ultrasonic guided waves in defective rockbolt systems and the bond quality of rockbolts under the combined action of pull-out load and confining pressure. The numerical simulation results show that the length and location of bond defects can be detected by ultrasonic guided waves under the combined action of pull-out load and confining pressure. Under no pull-out load, with increasing confining pressure, the low-frequency part of the guided wave frequency in the rockbolt increases, the high-frequency part decreases, the weakening effect of the confining pressure on the guided wave propagation law increases, and the bond quality of the rockbolt increases. The existence of defects cannot change the strengthening effect of the confining pressure on the guided wave propagation law under the same pull-out load or the weakening effect of the pull-out load on the guided wave propagation law under the same confining pressure.展开更多
A prestressed elastic medium containing a mode-Ⅲcrack is studied by means of the couple stress theory(CST).Based on the CST under initial stresses,a governing differential equation along with a mixed boundary value p...A prestressed elastic medium containing a mode-Ⅲcrack is studied by means of the couple stress theory(CST).Based on the CST under initial stresses,a governing differential equation along with a mixed boundary value problem is established.The singularities of the couple stress and force stress near the crack tips are analyzed through the asymptotic crack-tip fields resulting from the characteristic expansion method.To determine their intensity,a hypersingular integral equation is derived and numerically solved with the help of the Chebyshev polynomial.The obtained results show a strong size-dependence of the out-of-plane displacement on the crack and the couple stress intensity factor(CSIF)and the force stress intensity factor(FSIF)around the crack tips.The symmetric part of the shear stress has no singularity,and the skew-symmetric part related to the couple stress exhibits an r^(-3/2)singularity,in which r is the distance from the crack tip.The initial stresses also affect the crack tearing displacement and the CSIF and FSIF.展开更多
In recent years the synchronous reluctance machines(SynRMs)have received much attention.They have some good features such as high torque density,high reliability and low cost.This paper aims to give an overview of Syn...In recent years the synchronous reluctance machines(SynRMs)have received much attention.They have some good features such as high torque density,high reliability and low cost.This paper aims to give an overview of SynRMs with particular emphasis on the history,research status and industrial application.Besides,concept and basic operating principles of such machines are also described.Moreover,some hot spots of the research on the SynRMs are introduced.Several methods to improve the average torque and reduce torque ripple of the SynRMs in the past literatures are presented including topology design and control strategies.An overview of the methods from different aspects to realize high efficiency for the SynRMs is given which contain rotor optimization,winding configuration,material improvement,control schemes and so on.Some approaches suitable for high speed application are also introduced.It can be seen that the SynRMs have broad development prospects and great potential in industrial application.展开更多
Objective: To screen and analyze key express sequence tags (ESTs) which were differentially displayed in every period of SD rats' primary hepatic carcinoma and reveal the molecular mechanism of carcinogenesis. Met...Objective: To screen and analyze key express sequence tags (ESTs) which were differentially displayed in every period of SD rats' primary hepatic carcinoma and reveal the molecular mechanism of carcinogenesis. Methods: Using diethylnitrosamine (DENA) as a cancerigenic agent, animal models with different phases of primary hepatic cancer were constructed in SD rats. Rats were respectively sacrificed at d 14, d 28, d 56, d 77, d 105 and d 112 after the rats received DENA by gavage, then the livers were harvested. One part of the livers was classified according to their pathological changes, while the other was reserved for molecular mechanism studies on hepatocarcinogenesis. The differentially expressed genes were isolated from both normal and morbid tissues by mRNA differential display technique (DDRT-PCR). After the fragments were sequenced, bioinformatics were .used to analyze the results. Results: Twelve differentially expressed cDNA fragments were obtained. Nine fragments had the homology with known cDNA clones, especially EST-7 was similar to BN/SsNHsdMCW mitochondrion gene and the identity was 100% which suggested EST-7 may be the part of BN/SsNHsdMCW mitochondrion gene. In contrast, other three fragments (EST-1, EST-3 and EST-5) had extremely low identity to any genes registered in GENBANK databases. Conclusions: BN/SsNHsdMCW mitochondrion gene was expressed in different periods of hepatocarcinogenesis. Moreover, EST-I, EST-3 and EST-5 were suggested to contribute to the development of rat hepatocarcinogenesis, and thus may be candidates of new targets of oncogenes or cancer suppressor genes.展开更多
Extracorporeal membrane oxygenator(ECMO) has been in development for nearly 70 years, and the oxygenator has gone through several generations of optimizations, with advances from bubble oxygenators to membrane oxygena...Extracorporeal membrane oxygenator(ECMO) has been in development for nearly 70 years, and the oxygenator has gone through several generations of optimizations, with advances from bubble oxygenators to membrane oxygenators leading to more and more widespread use of ECMO. Membrane is the core of a ECMO system and the working mechanism of membrane oxygenator depends on the membrane material,from PDMS flat membrane to PMP hollow fiber membrane, which have experienced three generations.Blood compatibility on the surface of the membrane material is very vital, which directly determines the use duration of the oxygenator and can reduce the occurrence of complications. The mechanism of mass transfer is the basis of oxygenator operation and optimization. This review summarizes the membrane development history and preparation technology, modification approaches and mass transfer theory in the process of oxygen and blood exchange. We hoped that this review will provide more ideas for the study of gas blood exchange membrane.展开更多
The migration mechanisms,sources,and environmental risks of 29 legacy and emerging perfluorinated and polyfluoroalkyl species present in an oxidation pond(Ya'Er Lake)were investigated for treating sewage based on ...The migration mechanisms,sources,and environmental risks of 29 legacy and emerging perfluorinated and polyfluoroalkyl species present in an oxidation pond(Ya'Er Lake)were investigated for treating sewage based on the analysis of their occurrence and distribution.The concentration of per-and polyfluoroalkyl substances(PFAS)in pond area was between0.30 and 63.2 ng/g dw(dry weight),with the overall average concentration of 8.00 ng/g dw.Notably,the PFAS concentrations in the surface sediments near the sewage outlet in Pond-1(50.2 ng/g dw)and Pond-5(average 15.1 ng/g dw)were 1–2 orders of magnitude higher than those in other areas.In general,the legacy PFAS,i.e.,perfluorooctane sulfonic acid was considered to be the major pollutant in the polluted area,on average,accounting for 73.0%of the total concentration of PFAS pollutants.By evaluating the regional distribution of different PFAS homologs,the short-chain PFAS pollutants with lower K_(ow)were found to migrate farther in both horizontal and vertical directions.The sewage outlets in Pond-1 and Pond-5are the main pollution sources in polluted area and the emerging PFAS pollutants in Pond-5have replaced the legacy PFAS pollutants as the main pollutants.Based on positive matrix factorization analysis,three main industrial sources of PFAS pollutants in the study area were identified:protective coating,fire-fighting,and food packaging sources.Moreover,the environmental risk assessment results showed that most study areas exhibited medium environmental risk(0.01≤Risk quotient(RQ)<1),indicating that the ecological environment risks in this area need further attention.展开更多
Periodontitis is a complex chronic inflammatory disease.The invasion of pathogens induces the inflammatory microenvironment in periodontitis.Cell behavior changes in response to changes in the microenvironment,which i...Periodontitis is a complex chronic inflammatory disease.The invasion of pathogens induces the inflammatory microenvironment in periodontitis.Cell behavior changes in response to changes in the microenvironment,which in turn alters the local inflammatory microenvironment of the periodontium through factors secreted by cells.It has been confirmed that periodontal ligament stem cells(PDLSCs)are vital in the development of periodontal disease.Moreover,PDLSCs are the most effective cell type to be used for periodontium regeneration.This review focuses on changes in PDLSCs,their basic biological behavior,osteogenic differentiation,and drug effects caused by the inflammatory microenvironment,to provide a better understanding of the influence of these factors on periodontal tissue homeostasis.In addition,we discuss the underlying mechanism in detail behind the reciprocal responses of PDLSCs that affect the microenvironment.展开更多
World Health Organization has estimated that annually 24.3%(13.7 million of 56.1 million)of all global premature deaths and28.1%(1.57 million of 5.60 million)deaths among children under five,are linked to environmenta...World Health Organization has estimated that annually 24.3%(13.7 million of 56.1 million)of all global premature deaths and28.1%(1.57 million of 5.60 million)deaths among children under five,are linked to environmental factors[1].展开更多
In this paper,modified membranes containingβ-cyclodextrin(β-CD)and heparin coatings were prepared on the surface of poly-4-methyl-1-pentene(PMP)hollow fibrous membrane using the high strength adhesion of polydopamin...In this paper,modified membranes containingβ-cyclodextrin(β-CD)and heparin coatings were prepared on the surface of poly-4-methyl-1-pentene(PMP)hollow fibrous membrane using the high strength adhesion of polydopamine(PDA).In this paper,β-CD was added to increase the hemocompatibility of the PMP hollow fibrous membranes and the stability of the heparin coating.The uniformity of the heparin coating withβ-CD addition was better than that of the groups withoutβ-CD.After seven days of saline rinsing,the surface of the modified membranes withβ-CD addition still had a large amount of heparin present,which was more stable compared to the control group.After surface modification,the modified membrane changed from hydrophobic to hydrophilic.Importantly,the protein adsorption,platelet adhesion,and hemolysis rates of the modified membranes were significantly reduced compared with the pristine membranes.The APTT values were also significantly increased.The results showed that the modified membranes with the addition ofβ-CD had better hydrophilicity,can maintain the stability of heparin coating for a long time,and finally showed good hemocompatibility.展开更多
Precise control of circulating lipid levels is vital in both health and disease.We recently uncovered that bulk lipids,transported by lipoproteins,enter the circulation initially via the coat protein complex II(COPII)...Precise control of circulating lipid levels is vital in both health and disease.We recently uncovered that bulk lipids,transported by lipoproteins,enter the circulation initially via the coat protein complex II(COPII)in a condensation-dependent manner.Divalent manganese,acting as a signaling messenger,selectively controls COPII condensation to regulate lipid homeostasis in vivo.Here,we present evidence for a manganese-based therapy in murine models of hypolipidemia and hyperlipidemia.展开更多
A microwave-H202 process for sludge pretreatment exhibited high efticiencies of releasing organics, nitrogen, and phosphorus, but large quantifies of H202 residues were detected. A uniform design method was thus emplo...A microwave-H202 process for sludge pretreatment exhibited high efticiencies of releasing organics, nitrogen, and phosphorus, but large quantifies of H202 residues were detected. A uniform design method was thus employed in this study to further optimize H202 dosage by investigating effects of pH and H202 dosage on the amount of 1-I202 residue and releases of organics, nitrogen, and phosphorus. A regression model was established with pH and H202 dosage as the independent variables, and H202 residue and releases of organics, nitrogen, and phosphorus as the dependent variables. In the optimized microwave-H202 process, the pH value of the sludge was firstly adjusted to 11.0, then the sludge was heated to 80~C and H202 was dosed at a H202 :mixed liquor suspended solids (MLSS) ratio of 0.2, and the sludge was finally heated to 100~C by microwave irradiation. Compared to the microwave-H202 process without optimization, the H202 dosage and the utilization rate of H202 in the optimized microwave-H202 process were reduced by 80% and greatly improved by 3.87 times, respectively, when the H202:MLSS dosage ratio was decreased from 1.0 to 0.2, resulting in nearly the same release rate of soluble chemical oxygen demand in the microwave-H202 process without optimization at H202:MLSS ratio of 0.5.展开更多
The concentrations and geographical distribution of hexabromocyclododecane (HBCD) were investigated in 37 composite surface sediments from seven major river drainage basins in China, including Yangtze River, Yellow ...The concentrations and geographical distribution of hexabromocyclododecane (HBCD) were investigated in 37 composite surface sediments from seven major river drainage basins in China, including Yangtze River, Yellow River, Pearl River, Liaohe River, Haihe River, Tarim River and Ertix River. The detection frequency of HBCD was 54%, with the concentrations ranged from below limit of detection (LOD) to 206 ng/g dry weight. In general, the geographical distribution showed increasing trends from the upper reaches to the lower reaches of the rivers and from North China to Southeast China. Compared to other regions in the world, the average concentration of HBCD in sediments from Yangtze River drainage basin was at relatively high level, whereas those from other six river drainage basins were at lower or similar level. The highest HBCD concentration in sediment from Yangtze River Delta and the highest detection frequency of t-IBCD in Pearl River drainage basins suggested that the industrial and urban activities could evidently affect the HBCD distribution. HBCD diastereoisomer profiles showed that y-HBCD dominated in most of the sediment samples, followed by ct- and [3-HBCD, which was consistent with those in the commercial HBCD mixtures. Further risk assessment reflected that the average inventories of HBCD were 18.3, 5.87, 3.92, 2.50, 1.77 ng/cm2 in sediments from Pearl River, Haihe River, Tarim River, Yellow River and Yangtze River, respectively.展开更多
Swine manure was typical for the combined pollution of heavy metals and antibiotics. The effects of widely used veterinary antibiotic chlortetracycline(CTC), Cu and their combination on swine manure anaerobic digest...Swine manure was typical for the combined pollution of heavy metals and antibiotics. The effects of widely used veterinary antibiotic chlortetracycline(CTC), Cu and their combination on swine manure anaerobic digestion performance and microbial community have never been investigated. Thus, four 2 L anaerobic digestion reactors were established including reactor A(control), B(CTC spiked by 0.5 g/kg dry weight, dw), C(Cu spiked by 5 g/kg dw) and D(combination of CTC, 0.5 g/kg dw, and Cu, 5 g/kg dw), and dynamics of bacterial and archaeal community structure was investigated using high throughput sequencing method. Results showed that addition of CTC and Cu separately could increase the total biogas production by21.6% and 15.8%, respectively, while combination of CTC and Cu severely inhibited anaerobic digestion(by 30.3%). Furthermore, corresponding to different stages and reactors, four kinds of microbes including bacteria and archaea were described in detail, and the effects of CTC, Cu and their combination mainly occurred at hydrolysis and acidification phases. The addition of Cu alone changed the dynamics of archaeal community significantly. It was genus Methanomassiliicoccus that dominated at the active methane production for A, B and D, while it was genus Methanobrevibacter and Methanoculleus for C.展开更多
Soil is a major sink for per-and perfluoroalkyl substances(PFAS),wherein PFAS may be transferred through the food chain to predators at upper trophic levels,which poses a threat to human health.Herein,the concentratio...Soil is a major sink for per-and perfluoroalkyl substances(PFAS),wherein PFAS may be transferred through the food chain to predators at upper trophic levels,which poses a threat to human health.Herein,the concentrations and distributions of legacy and novel PFAS in topsoil samples from different functional areas in Tianjin were comprehensively investigated.Seventeen PFAS congeners were identified,with concentrations ranging from 0.21 ng/g to 5.35 ng/g,with a mean concentration of 1.25 ng/g.The main PFAS in the topsoil was perfluorooctanoic acid(PFOA).6:2 chlorinated polyfluorinated ether sulfonate(6:2 ClPFESA;<MDL–1.95 ng/g,mean 0.11 ng/g),as an emerging substitute for perfluorooctane sulfonate(PFOS),was also detected in the topsoil.It showed slightly higher concentrations than PFOS(<MDL–1.62 ng/g,mean 0.10 ng/g),indicating it has gradually replaced legacy PFOS in this area.Based on the positive-definite matrix factor(PMF)receptor model,the major PFAS sources was dominated by textile treatment,metal electroplating plants,and some potential precursors of PFAS with longer chains(>C8)were the major sources(43.4%),followed by food packaging as well as coating materials(25.5%).In addition,Spearman correlation analysis and the structural equation model showed that population density significantly impacted the PFAS distribution in the topsoil of Tianjin.展开更多
基金Science and Technology Plan of Shenzhen,Grant/Award Number:JCYJ20200109140410340National Natural Science Foundation of China,Grant/Award Number:62073004。
文摘As one of the most effective methods to improve the accuracy and robustness of speech tasks,the audio-visual fusion approach has recently been introduced into the field of Keyword Spotting(KWS).However,existing audio-visual keyword spotting models are limited to detecting isolated words,while keyword spotting for unconstrained speech is still a challenging problem.To this end,an Audio-Visual Keyword Transformer(AVKT)network is proposed to spot keywords in unconstrained video clips.The authors present a transformer classifier with learnable CLS tokens to extract distinctive keyword features from the variable-length audio and visual inputs.The outputs of audio and visual branches are combined in a decision fusion module.As humans can easily notice whether a keyword appears in a sentence or not,our AVKT network can detect whether a video clip with a spoken sentence contains a pre-specified keyword.Moreover,the position of the keyword is localised in the attention map without additional position labels.Exper-imental results on the LRS2-KWS dataset and our newly collected PKU-KWS dataset show that the accuracy of AVKT exceeded 99%in clean scenes and 85%in extremely noisy conditions.The code is available at https://github.com/jialeren/AVKT.
文摘Lung cancer is the most prevalent cancer diagnosis and the leading cause of cancer death worldwide.Therapeutic failure in lung cancer(LUAD)is heavily influenced by drug resistance.This challenge stems from the diverse cell populations within the tumor,each having unique genetic,epigenetic,and phenotypic profiles.Such variations lead to varied therapeutic responses,thereby contributing to tumor relapse and disease progression.Methods:The Genomics of Drug Sensitivity in Cancer(GDSC)database was used in this investigation to obtain the mRNA expression dataset,genomic mutation profile,and drug sensitivity information of NSCLS.Machine Learning(ML)methods,including Random Forest(RF),Artificial Neurol Network(ANN),and Support Vector Machine(SVM),were used to predict the response status of each compound based on the mRNA and mutation characteristics determined using statistical methods.The most suitable method for each drug was proposed by comparing the prediction accuracy of different ML methods,and the selected mRNA and mutation characteristics were identified as molecular features for the drug-responsive cancer subtype.Finally,the prognostic influence of molecular features on the mutational subtype of LUAD in publicly available datasets.Results:Our analyses yielded 1,564 gene features and 45 mutational features for 46 drugs.Applying the ML approach to predict the drug response for each medication revealed an upstanding performance for SVM in predicting Afuresertib drug response(area under the curve[AUC]0.875)using CIT,GAS2L3,STAG3L3,ATP2B4-mut,and IL15RA-mut as molecular features.Furthermore,the ANN algorithm using 9 mRNA characteristics demonstrated the highest prediction performance(AUC 0.780)in Gefitinib with CCL23-mut.Conclusion:This work extensively investigated the mRNA and mutation signatures associated with drug response in LUAD using a machine-learning approach and proposed a priority algorithm to predict drug response for different drugs.
文摘A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Therefore, in this study, confining pressure and pull-out load are applied to grouted rockbolt systems with bond defects by a numerical simulation method, and the rockbolt is detected by ultrasonic guided waves to study the propagation law of ultrasonic guided waves in defective rockbolt systems and the bond quality of rockbolts under the combined action of pull-out load and confining pressure. The numerical simulation results show that the length and location of bond defects can be detected by ultrasonic guided waves under the combined action of pull-out load and confining pressure. Under no pull-out load, with increasing confining pressure, the low-frequency part of the guided wave frequency in the rockbolt increases, the high-frequency part decreases, the weakening effect of the confining pressure on the guided wave propagation law increases, and the bond quality of the rockbolt increases. The existence of defects cannot change the strengthening effect of the confining pressure on the guided wave propagation law under the same pull-out load or the weakening effect of the pull-out load on the guided wave propagation law under the same confining pressure.
基金Project supported by the National Natural Science Foundation of China(Nos.11672336,12072374)。
文摘A prestressed elastic medium containing a mode-Ⅲcrack is studied by means of the couple stress theory(CST).Based on the CST under initial stresses,a governing differential equation along with a mixed boundary value problem is established.The singularities of the couple stress and force stress near the crack tips are analyzed through the asymptotic crack-tip fields resulting from the characteristic expansion method.To determine their intensity,a hypersingular integral equation is derived and numerically solved with the help of the Chebyshev polynomial.The obtained results show a strong size-dependence of the out-of-plane displacement on the crack and the couple stress intensity factor(CSIF)and the force stress intensity factor(FSIF)around the crack tips.The symmetric part of the shear stress has no singularity,and the skew-symmetric part related to the couple stress exhibits an r^(-3/2)singularity,in which r is the distance from the crack tip.The initial stresses also affect the crack tearing displacement and the CSIF and FSIF.
基金in part by the National Natural Science Foundation of China (NSFC) under Grant 52107046in part by the Fundamental Research Funds for the Central Universities,HUST (2021XXJS009)
文摘In recent years the synchronous reluctance machines(SynRMs)have received much attention.They have some good features such as high torque density,high reliability and low cost.This paper aims to give an overview of SynRMs with particular emphasis on the history,research status and industrial application.Besides,concept and basic operating principles of such machines are also described.Moreover,some hot spots of the research on the SynRMs are introduced.Several methods to improve the average torque and reduce torque ripple of the SynRMs in the past literatures are presented including topology design and control strategies.An overview of the methods from different aspects to realize high efficiency for the SynRMs is given which contain rotor optimization,winding configuration,material improvement,control schemes and so on.Some approaches suitable for high speed application are also introduced.It can be seen that the SynRMs have broad development prospects and great potential in industrial application.
基金supported by the Key Program for Science and Technology Development of Henan Province [122102310174]the Zoology Key Subject of Henan Province
文摘Objective: To screen and analyze key express sequence tags (ESTs) which were differentially displayed in every period of SD rats' primary hepatic carcinoma and reveal the molecular mechanism of carcinogenesis. Methods: Using diethylnitrosamine (DENA) as a cancerigenic agent, animal models with different phases of primary hepatic cancer were constructed in SD rats. Rats were respectively sacrificed at d 14, d 28, d 56, d 77, d 105 and d 112 after the rats received DENA by gavage, then the livers were harvested. One part of the livers was classified according to their pathological changes, while the other was reserved for molecular mechanism studies on hepatocarcinogenesis. The differentially expressed genes were isolated from both normal and morbid tissues by mRNA differential display technique (DDRT-PCR). After the fragments were sequenced, bioinformatics were .used to analyze the results. Results: Twelve differentially expressed cDNA fragments were obtained. Nine fragments had the homology with known cDNA clones, especially EST-7 was similar to BN/SsNHsdMCW mitochondrion gene and the identity was 100% which suggested EST-7 may be the part of BN/SsNHsdMCW mitochondrion gene. In contrast, other three fragments (EST-1, EST-3 and EST-5) had extremely low identity to any genes registered in GENBANK databases. Conclusions: BN/SsNHsdMCW mitochondrion gene was expressed in different periods of hepatocarcinogenesis. Moreover, EST-I, EST-3 and EST-5 were suggested to contribute to the development of rat hepatocarcinogenesis, and thus may be candidates of new targets of oncogenes or cancer suppressor genes.
基金financial support of the National Key Research and Development Program of China (2020YFC0862903)the National Natural Science Foundation of China (22078146)+1 种基金the Key Research and Development program of Jiangsu Province (BE2021022)the Natural Science Foundation of Jiangsu Province (BK20200091)。
文摘Extracorporeal membrane oxygenator(ECMO) has been in development for nearly 70 years, and the oxygenator has gone through several generations of optimizations, with advances from bubble oxygenators to membrane oxygenators leading to more and more widespread use of ECMO. Membrane is the core of a ECMO system and the working mechanism of membrane oxygenator depends on the membrane material,from PDMS flat membrane to PMP hollow fiber membrane, which have experienced three generations.Blood compatibility on the surface of the membrane material is very vital, which directly determines the use duration of the oxygenator and can reduce the occurrence of complications. The mechanism of mass transfer is the basis of oxygenator operation and optimization. This review summarizes the membrane development history and preparation technology, modification approaches and mass transfer theory in the process of oxygen and blood exchange. We hoped that this review will provide more ideas for the study of gas blood exchange membrane.
基金supported by the National Natural Science Foundation of China (Nos.22136006 and 51972302)the K.C.Wong Education Foundation of China (No.GJTD-2020-03)。
文摘The migration mechanisms,sources,and environmental risks of 29 legacy and emerging perfluorinated and polyfluoroalkyl species present in an oxidation pond(Ya'Er Lake)were investigated for treating sewage based on the analysis of their occurrence and distribution.The concentration of per-and polyfluoroalkyl substances(PFAS)in pond area was between0.30 and 63.2 ng/g dw(dry weight),with the overall average concentration of 8.00 ng/g dw.Notably,the PFAS concentrations in the surface sediments near the sewage outlet in Pond-1(50.2 ng/g dw)and Pond-5(average 15.1 ng/g dw)were 1–2 orders of magnitude higher than those in other areas.In general,the legacy PFAS,i.e.,perfluorooctane sulfonic acid was considered to be the major pollutant in the polluted area,on average,accounting for 73.0%of the total concentration of PFAS pollutants.By evaluating the regional distribution of different PFAS homologs,the short-chain PFAS pollutants with lower K_(ow)were found to migrate farther in both horizontal and vertical directions.The sewage outlets in Pond-1 and Pond-5are the main pollution sources in polluted area and the emerging PFAS pollutants in Pond-5have replaced the legacy PFAS pollutants as the main pollutants.Based on positive matrix factorization analysis,three main industrial sources of PFAS pollutants in the study area were identified:protective coating,fire-fighting,and food packaging sources.Moreover,the environmental risk assessment results showed that most study areas exhibited medium environmental risk(0.01≤Risk quotient(RQ)<1),indicating that the ecological environment risks in this area need further attention.
基金supported by the Jilin Provincial Department of Finance(No.jcsz2020304-9)the Guangzhou Medical University Student Innovation Ability Improvement Program(No.(2022)66-113),China。
文摘Periodontitis is a complex chronic inflammatory disease.The invasion of pathogens induces the inflammatory microenvironment in periodontitis.Cell behavior changes in response to changes in the microenvironment,which in turn alters the local inflammatory microenvironment of the periodontium through factors secreted by cells.It has been confirmed that periodontal ligament stem cells(PDLSCs)are vital in the development of periodontal disease.Moreover,PDLSCs are the most effective cell type to be used for periodontium regeneration.This review focuses on changes in PDLSCs,their basic biological behavior,osteogenic differentiation,and drug effects caused by the inflammatory microenvironment,to provide a better understanding of the influence of these factors on periodontal tissue homeostasis.In addition,we discuss the underlying mechanism in detail behind the reciprocal responses of PDLSCs that affect the microenvironment.
基金supported by the National Natural Science Foundation of China(22065017 and 22163003)China Postdoctoral Science Foundation(BX2021029 and 2021M700353)+2 种基金Jiangxi Provincial Natural Science Foundation(20224BAB214019 and 20202BABL203028)the Opening Foundation of the State Key Laboratory of Organic-Inorganic Composites,Beijing University of Chemical Technology(oic-202201011)the Science and Technology Project of Jiangxi Provincial Department of Education(GJJ211801)。
基金supported by the National Natural Science Foundation of China(22136006,22021003)the K.C.Wong Education Foundation of China(GJTD-2020-03)。
文摘World Health Organization has estimated that annually 24.3%(13.7 million of 56.1 million)of all global premature deaths and28.1%(1.57 million of 5.60 million)deaths among children under five,are linked to environmental factors[1].
基金This research was supported by National Key R&D Program of China(2020YFC0862903)the National Natural Science Foundation of China(22078146)+1 种基金the Key R&D program of Jiangsu Province(BE2021022)The Natural Science Foundation of Jiangsu Province(BK20200091).
文摘In this paper,modified membranes containingβ-cyclodextrin(β-CD)and heparin coatings were prepared on the surface of poly-4-methyl-1-pentene(PMP)hollow fibrous membrane using the high strength adhesion of polydopamine(PDA).In this paper,β-CD was added to increase the hemocompatibility of the PMP hollow fibrous membranes and the stability of the heparin coating.The uniformity of the heparin coating withβ-CD addition was better than that of the groups withoutβ-CD.After seven days of saline rinsing,the surface of the modified membranes withβ-CD addition still had a large amount of heparin present,which was more stable compared to the control group.After surface modification,the modified membrane changed from hydrophobic to hydrophilic.Importantly,the protein adsorption,platelet adhesion,and hemolysis rates of the modified membranes were significantly reduced compared with the pristine membranes.The APTT values were also significantly increased.The results showed that the modified membranes with the addition ofβ-CD had better hydrophilicity,can maintain the stability of heparin coating for a long time,and finally showed good hemocompatibility.
基金The work is supported by the National Natural Science Foundation of China(NSFC:32125021,92254308,91957119,91954001,31571213 to X.W.C,32100947 to X.W.,and 62027901 to J.T.)the National Key R&D Program(2021YFA0804802).
文摘Precise control of circulating lipid levels is vital in both health and disease.We recently uncovered that bulk lipids,transported by lipoproteins,enter the circulation initially via the coat protein complex II(COPII)in a condensation-dependent manner.Divalent manganese,acting as a signaling messenger,selectively controls COPII condensation to regulate lipid homeostasis in vivo.Here,we present evidence for a manganese-based therapy in murine models of hypolipidemia and hyperlipidemia.
基金supported by the National Natural Science Foundation of China (No. 51008297)the Hi-Tech Research and Development Program (863) of China(No. 2007AA06Z347)the National Major Science & Technology Projects for Water Pollution Control and Management (No. 2012ZX07202-005)
文摘A microwave-H202 process for sludge pretreatment exhibited high efticiencies of releasing organics, nitrogen, and phosphorus, but large quantifies of H202 residues were detected. A uniform design method was thus employed in this study to further optimize H202 dosage by investigating effects of pH and H202 dosage on the amount of 1-I202 residue and releases of organics, nitrogen, and phosphorus. A regression model was established with pH and H202 dosage as the independent variables, and H202 residue and releases of organics, nitrogen, and phosphorus as the dependent variables. In the optimized microwave-H202 process, the pH value of the sludge was firstly adjusted to 11.0, then the sludge was heated to 80~C and H202 was dosed at a H202 :mixed liquor suspended solids (MLSS) ratio of 0.2, and the sludge was finally heated to 100~C by microwave irradiation. Compared to the microwave-H202 process without optimization, the H202 dosage and the utilization rate of H202 in the optimized microwave-H202 process were reduced by 80% and greatly improved by 3.87 times, respectively, when the H202:MLSS dosage ratio was decreased from 1.0 to 0.2, resulting in nearly the same release rate of soluble chemical oxygen demand in the microwave-H202 process without optimization at H202:MLSS ratio of 0.5.
基金supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (No.2007BAC27B01)the Young Scientists Fund of the National Natural Science Foundation of China(No.21107121,21107122,20907059)
文摘The concentrations and geographical distribution of hexabromocyclododecane (HBCD) were investigated in 37 composite surface sediments from seven major river drainage basins in China, including Yangtze River, Yellow River, Pearl River, Liaohe River, Haihe River, Tarim River and Ertix River. The detection frequency of HBCD was 54%, with the concentrations ranged from below limit of detection (LOD) to 206 ng/g dry weight. In general, the geographical distribution showed increasing trends from the upper reaches to the lower reaches of the rivers and from North China to Southeast China. Compared to other regions in the world, the average concentration of HBCD in sediments from Yangtze River drainage basin was at relatively high level, whereas those from other six river drainage basins were at lower or similar level. The highest HBCD concentration in sediment from Yangtze River Delta and the highest detection frequency of t-IBCD in Pearl River drainage basins suggested that the industrial and urban activities could evidently affect the HBCD distribution. HBCD diastereoisomer profiles showed that y-HBCD dominated in most of the sediment samples, followed by ct- and [3-HBCD, which was consistent with those in the commercial HBCD mixtures. Further risk assessment reflected that the average inventories of HBCD were 18.3, 5.87, 3.92, 2.50, 1.77 ng/cm2 in sediments from Pearl River, Haihe River, Tarim River, Yellow River and Yangtze River, respectively.
基金supported by the National Natural Science Foundation of China(Nos.21377151,21577161 and 21677161)the State Key Joint Laboratory of Environmental Simulation and Pollution Control of China(No.16Z04ESPCR)+1 种基金the National Major Science&Technology Projects for Water Pollution Control and Management of China(No.2015ZX07203-007)the National Key R&D program(No.2016YFD0501405)
文摘Swine manure was typical for the combined pollution of heavy metals and antibiotics. The effects of widely used veterinary antibiotic chlortetracycline(CTC), Cu and their combination on swine manure anaerobic digestion performance and microbial community have never been investigated. Thus, four 2 L anaerobic digestion reactors were established including reactor A(control), B(CTC spiked by 0.5 g/kg dry weight, dw), C(Cu spiked by 5 g/kg dw) and D(combination of CTC, 0.5 g/kg dw, and Cu, 5 g/kg dw), and dynamics of bacterial and archaeal community structure was investigated using high throughput sequencing method. Results showed that addition of CTC and Cu separately could increase the total biogas production by21.6% and 15.8%, respectively, while combination of CTC and Cu severely inhibited anaerobic digestion(by 30.3%). Furthermore, corresponding to different stages and reactors, four kinds of microbes including bacteria and archaea were described in detail, and the effects of CTC, Cu and their combination mainly occurred at hydrolysis and acidification phases. The addition of Cu alone changed the dynamics of archaeal community significantly. It was genus Methanomassiliicoccus that dominated at the active methane production for A, B and D, while it was genus Methanobrevibacter and Methanoculleus for C.
基金financial support from the National Key Research and Development Program,China under Grant(No.2018YFC021310)the National Natural Science Foundation of China(No.21625702)the Science Fund for Creative Research Groups(No.22021003)。
文摘Soil is a major sink for per-and perfluoroalkyl substances(PFAS),wherein PFAS may be transferred through the food chain to predators at upper trophic levels,which poses a threat to human health.Herein,the concentrations and distributions of legacy and novel PFAS in topsoil samples from different functional areas in Tianjin were comprehensively investigated.Seventeen PFAS congeners were identified,with concentrations ranging from 0.21 ng/g to 5.35 ng/g,with a mean concentration of 1.25 ng/g.The main PFAS in the topsoil was perfluorooctanoic acid(PFOA).6:2 chlorinated polyfluorinated ether sulfonate(6:2 ClPFESA;<MDL–1.95 ng/g,mean 0.11 ng/g),as an emerging substitute for perfluorooctane sulfonate(PFOS),was also detected in the topsoil.It showed slightly higher concentrations than PFOS(<MDL–1.62 ng/g,mean 0.10 ng/g),indicating it has gradually replaced legacy PFOS in this area.Based on the positive-definite matrix factor(PMF)receptor model,the major PFAS sources was dominated by textile treatment,metal electroplating plants,and some potential precursors of PFAS with longer chains(>C8)were the major sources(43.4%),followed by food packaging as well as coating materials(25.5%).In addition,Spearman correlation analysis and the structural equation model showed that population density significantly impacted the PFAS distribution in the topsoil of Tianjin.