Tree peony(Paeonia rockii)is an excellent woody oilseed crop,known for its highα-linolenic acid(ALA,∼45%)content,which is of great value for human health.However,the mechanisms underlying this high-level ALA accumul...Tree peony(Paeonia rockii)is an excellent woody oilseed crop,known for its highα-linolenic acid(ALA,∼45%)content,which is of great value for human health.However,the mechanisms underlying this high-level ALA accumulation in tree peony seeds are poorly understood.In this study,we evaluated the dynamic changes in the lipidomic profile of P.rockii seeds during development.A total of 760 lipid molecules were identified in P.rockii seeds;triacylglycerol(TAG)lipid molecules showed the highest abundance and diversity,both increasing during seed development.Particularly,ALA was the predominant fatty acid at the TAG sn-3 position.We further characterized two diacylglycerol acyltransferase(DGAT)genes and three phospholipid:diacylglycerol acyltransferase(PDAT)genes involved in the transfer of fatty acids to the TAG sn-3 position.Gene expression and subcellular localization analyses suggested that PrDGATs and PrPDATs may function as endoplasmic reticulum-localized proteins in seed TAG biosynthesis.In vitro functional complementation analysis showed different substrate specificities,with PrPDAT2 having a specific preference for ALA.Multiple biological assays demonstrated that PrDGAT1,PrDGAT2,PrPDAT1-2,and PrPDAT2 promote oil synthesis.Specifically,PrPDAT2 leads to preferential ALA in the oil.Our findings provide novel functional evidence of the roles of PrDGAT1 and PrPDAT2,which are potential targets for increasing the ALA yield in tree peony and other oilseed crops.展开更多
We simulate the evolution of hydrogen concentration and gas pore formation as equiaxed dendrites grow during solidification of a hypoeutectic aluminum-silicon(Al-Si)alloy.The applied lattice Boltzmann-cellular automat...We simulate the evolution of hydrogen concentration and gas pore formation as equiaxed dendrites grow during solidification of a hypoeutectic aluminum-silicon(Al-Si)alloy.The applied lattice Boltzmann-cellular automaton-finite difference model incorporates the physical mechanisms of solute and hydrogen partitioning on the solid/liquid interface,as well as the transports of solute and hydrogen.After the quantitative validation by the simulation of capillary intrusion,the model is utilized to investigate the growth of the equiaxed dendrites and hydrogen porosity formation for an Al-(5 wt.%)Si alloy under different solidification conditions.The simulation data reveal that the gas pores favorably nucleate in the corners surrounded by the nearby dendrite arms.Then,the gas pores grow in a competitive mode.With the cooling rate increasing,the competition among different growing gas pores is found to be hindered,which accordingly increases the pore number density in the final solidification microstructure.In the late solidification stage,even though the solid fraction is increasing,the mean concentration of hydrogen in the residue melt tends to be constant,corresponding to a dynamic equilibrium state of hydrogen concentration in liquid.As the cooling rate increases or the initial hydrogen concentration decreases,the temperature of gas pore nucleation,the porosity fraction,and the mean porosity size decrease,whilst the mean hydrogen concentration in liquid increases in the late solidification stage.The simulated data present identical trends with the experimental results reported in literature.展开更多
The chemical and physical characteristics of PM2.5, especially their temporal and geographical variations, have been explored in metropolitan Hangzhou area (China) by a field campaign from September 2010 to July 2011....The chemical and physical characteristics of PM2.5, especially their temporal and geographical variations, have been explored in metropolitan Hangzhou area (China) by a field campaign from September 2010 to July 2011. Annual average concentrations of PM2.5 and PM10 during non-raining days were 106 - 131 μg.m-3 and 127 - 158 μg.m-3, respectively, at three stations in urban breathing zones, while corresponding concentrations of PM2.5 and PM10 at an urban background station (16 mabove ground level in a park) were 78 and 104 μg.m-3, respectively. For comparison, the annual average PM10 concentration at a suburban station (5 mAGL) was 93 μg.m-3. Detailed chemical analyses were also conducted for all samples collected during the campaign. We found that toxic metals (Cd, As, Pb, Zn, Mo, Cu, Hg) were highly enriched in the breathing zones due to anthropogenic activities, while soluble ions (, , ) and total carbon accounted for majority of PM2.5 mass. Unlike most areas in China where sulfate was several times of nitrate in fine PM, nitrate was as important as sulfate and highly correlated with ammonium during the campaign. Thus, a historical shift from sulfate-dominant fine PM to nitrate-dominant fine PM was documented.展开更多
Neutrophils play an essential role in the defense against bacterial infections and orchestrate both the innate and adaptive immune responses.With their abundant numbers,diverse function and short life span,these cells...Neutrophils play an essential role in the defense against bacterial infections and orchestrate both the innate and adaptive immune responses.With their abundant numbers,diverse function and short life span,these cells are at the forefront of immune responses,and have gained attention in recent years because of their presence in tumor sites.Neutrophil involvement pertains to tumor cells'ability to construct a suitable tumor microenvironment(TME)that accelerates their own growth and malignancy,by facilitating their interaction with surrounding cells through the circulatory and lymphatic systems,thereby influencing tumor development and progression.Studies have indicated both pro-and anti-tumor properties of infiltrating neutrophils.The TME can exploit neutrophil function,recruitment,and even production,thus resulting in pro-tumor properties of neutrophils,including promotion of genetic instability,tumor cell proliferation,angiogenesis and suppression of anti-tumor or inflammatory response.In contrast,neutrophils can mediate anti-tumor resistance by direct cytotoxicity to the tumor cells or by facilitating anti-tumor functions via crosstalk with T cells.Here,we summarize current knowledge regarding the effects of neutrophil heterogeneity under homeostatic and tumor conditions,including neutrophil phenotype and function,in cancer biology.展开更多
Laser oscillating welding was employed to fabricate Al-Si coated press-hardened steel(PHS)to improve the element homogeneity in the fusion zone.Laser oscillating welding was employed with various oscillation amplitude...Laser oscillating welding was employed to fabricate Al-Si coated press-hardened steel(PHS)to improve the element homogeneity in the fusion zone.Laser oscillating welding was employed with various oscillation amplitudes(0 mm,0.5 mm and 1.3 mm)in this present.Ni foil of 0.06 mm thickness was used as an interlayer between two tailored PHS welded.The weld morphology,elemental profile,microstructure and tensile strength of welded joints were studied.The results showed that full penetration weld without any weld defects were achieved for any oscillation amplitudes,and weld width increased with increasing oscillation amplitudes.With the oscillation amplitudes increased,Ni and Al had an uneven elemental profile due to strong stirring force,but the Ni and Al content in the weld was decreased and Ni had a sharp descent compared to Al element.Only fewδ-ferrite was presented in fusion line with the oscillation amplitudes increased to 1.3 mm.The oscillation amplitudes did not have an effect on the tensile properties,which was similar to that of base metal.But if keeping increasing the oscillation amplitudes or reducing the thickness of Ni interlayer,it has a potential risk to form more and moreδferrite such that deteriorate the mechnical properties of welded joints.展开更多
The mud crab Scylla paramamosain is a key species in China due to its high nutritional value and great economic worth and has grown in popularity.Myo-inositol can modulate versatile physiological functions in aquatic ...The mud crab Scylla paramamosain is a key species in China due to its high nutritional value and great economic worth and has grown in popularity.Myo-inositol can modulate versatile physiological functions in aquatic animals.In the present study,S.paramamosain megalopa were given graded concentrations of myo-inositol(0,1,2,4,and 8 ppm)by water immersion to explore how their metamorphosis would be affected.The results showed that supplementing with myo-inositol remarkably increased transformation and survival rate from megalopa to crablet by at least 1.16 and 1.26 times,respectively.To decipher the molecular mechanism of how myo-inositol increases metamorphosis and survival rate,we further performed transcriptome-based gene expression profiling of both megalopa and crablet treated with myo-inositol.The integrative transcriptome analyses predicted that the differentially expressed genes(DEGs)were significantly enriched in chitinase activity,structural constituent of cuticle,and chitin binding,which are associated with the decomposition and reconstruction of cuticle.qPCR results confirmed that myo-inositol mediated gene expression levels of the above cuticle-related pathways.Considering the importance of the cuticle in exoskeleton formation and molting,it can be concluded that myo-inositol-induced changes in the cuticle decomposition and reconstruction might have accelerated the transformation from megalopa to crablet of S.paramamosain.Besides,numerous DEGs were significantly enriched in protein digestion and absorption,amino sugar and nucleotide sugar metabolism.It implies that myo-inositol may improve survival by regulating energy or nutrient absorption.Additionally,the accelerated metamorphosis by myo-inositol may improve survival from megalopa to crablet of S.paramamosain.Overall,this study will provide the first insights into the underlying molecular mechanisms by which myo-inositol increases metamorphosis and survival.展开更多
Due to the use of more adjuvant therapies and the increasing prevalence of associated diseases,nontraumatic osteonecrosis of the femoral head(ONFH)has become a substantial worldwide health issue;while glucocorticoid a...Due to the use of more adjuvant therapies and the increasing prevalence of associated diseases,nontraumatic osteonecrosis of the femoral head(ONFH)has become a substantial worldwide health issue;while glucocorticoid administration was the highest-ranked risk factor,with a proportion ranging from 26.35 to 55.75%.1 Albeit with similar radiological features,glucocorticoid-induced ONFH(GONFH)manifested a greater probability for advance-tolate-stage(post-collapse)lesions in comparison with its non-glucocorticoid-induced counterparts.i1 Therefore,an accurate and timely diagnosis of osteonecrosis following glucocorticoid therapy is of great significance to initiate nonoperative treatment regimens or joint-preserving procedures,slow disease progression,and defer or avert joint arthroplasty.展开更多
In this study, the influences of accumulated mileage(deterioration) and technological changes(emission standards) on emission factors(EFs) of regulated pollutants(CO, HC, and NO_x) from gasoline passenger vehicles wer...In this study, the influences of accumulated mileage(deterioration) and technological changes(emission standards) on emission factors(EFs) of regulated pollutants(CO, HC, and NO_x) from gasoline passenger vehicles were investigated based on Inspection and Maintenance(I/M) data using the chassis dynamometer method. The accumulated mileage of passenger vehicles was significantly linearly correlated with vehicle age. For most cases,the average EFs of CO, HC and NO_x were significantly linearly correlated with accumulated mileage, indicating that emission deterioration had a significant impact on pollutant EFs.Implemented emission standards markedly influenced the EFs of regulated pollutants, and EFs markedly decreased with progressing emission standards. The present study also compared EFs of regulated pollutants between this study and the International vehicle emission(IVE) model, and marked differences in EFs were seen with variations in emission standards, vehicle types and accumulated mileage; NO_x EFs in this study were higher than in the IVE model. The results provide new insight into estimating regulated pollutant emissions using the IVE model.展开更多
Gaseous peroxides play important roles in atmospheric chemistry. To understand the pathways of the formation and removal of peroxides, atmospheric peroxide concentrations and their controlling factors were measured fr...Gaseous peroxides play important roles in atmospheric chemistry. To understand the pathways of the formation and removal of peroxides, atmospheric peroxide concentrations and their controlling factors were measured from 7:00 to 20:00 in September, October, and November 2013 at a heavily trafficked residential site in Beijing, China, with average concentrations of hydrogen peroxide(H_2O_2) and methyl hydroperoxide(MHP) at 0.55 ppb and 0.063 ppb, respectively. H_2O_2 concentrations were higher in the afternoon and lower in the morning and evening, while MHP concentrations did not exhibit a regular diurnal pattern. Both H_2O_2 and MHP concentrations increased at dusk in most cases. Both peroxides displayed monthly variations with higher concentrations in September. These results suggested that photochemical activity was the main controlling factor on variations of H_2O_2 concentrations during the measurement period. Increasing concentrations of volatile organic compounds emitted by motor vehicles were important contributors to H_2O_2 and MHP enrichment. High levels of H_2O_2 and MHP concentrations which occurred during the measurement period probably resulted from the transport of a polluted air mass with high water vapor content passing over the Bohai Bay, China.展开更多
To cope with an increasingly turbulent environment,manufacturing firms increasingly implement integration practices to enhance flexibility in the production process.This research develops a framework to explore the re...To cope with an increasingly turbulent environment,manufacturing firms increasingly implement integration practices to enhance flexibility in the production process.This research develops a framework to explore the relationships among organizational integration practices,manufacturing flexibility,and competitive advantage.The study develops valid and reliable instruments to measure these constructs,and it applies structural equation modeling to test relationships among these variables using a large sample.The results indicate strong,positive,and direct relationships between organizational integration practices and manufacturing flexibility,and between manufacturing flexibility and competitive advantage.The results also indicate that organizational integration practices enhance competitive advantage directly as well as indirectly by facilitating manufacturing flexibility.展开更多
Osteonecrosis of the femoral head(ONFH)is a devastating musculoskeletal disease characterized by the impaired circulation of bone.The purpose of this study was to explore the underlying mechanisms of the protective ef...Osteonecrosis of the femoral head(ONFH)is a devastating musculoskeletal disease characterized by the impaired circulation of bone.The purpose of this study was to explore the underlying mechanisms of the protective effect of icariin on the glucocorticoid-induced injury of bone microvascular endothelial cells(BMECs).Normal BMECs were extracted from the femoral heads by enzymatic isolation and magneticactivated cell sorting methods.Dexamethasone and icariin were used to intervene BMECs in microfluidic organ chips,and phalloidin staining was conducted to observe the cell morphology and viability.Then next-generation transcriptome sequencing and real-time quantitative reverse transcription-polymerase chain reaction(q RT-PCR)were performed to identify the differentially expressed genes(DEGs)in different groups.Through the microfluidic organ chip,it can be observed that after dexamethasone intervention,the filamentous structure in cell fibers disappeared and the cell morphology changed from spindle to round until death.Icariin could relieve these changes and showed a protective effect on glucocorticoiddamaged BMECs.In addition,201 DEGs were detected between the icariin protection group and the dexamethasone group,which were significantly enriched in 17 signaling pathways.8 of the top ten selected hub genes(IL6,PTGS2,VEGFA,etc.)were confirmed by q RT-PCR.Transcription factors(TFs)-gene network showed 63 connections between 18 TFs and 12 DEGs.For instance,GATA2 could regulate 5 DEGs.The associations between 92 mi RNA and 12 DEGs were visualized in a mi RNA-gene network.The hub mi RNA,has-mir-335–5 p was predicted to interact with 8 DEGs(PTGS2,VEGFA,etc.).Microfluidic organ chips could provide excellent morphological results for cell experiments,by which it could be observed that icariin showed a protective effect on the glucocorticoid-induced injury of BMECs.Beside,these DEGs,possible regulatory TF(GATA2,FOXC1,etc.)and mi RNA(has-mir-335–5 p)might be dysregulated in the initiation of ONFH and have prospective importance in ONFH diagnosis and therapy.展开更多
This paper proposes a push-pull airflow combined with a top draft hood to conduct local exhaust in a rubber workshop.Field measurements are carried out to investigate the characteristics of the emission source,while n...This paper proposes a push-pull airflow combined with a top draft hood to conduct local exhaust in a rubber workshop.Field measurements are carried out to investigate the characteristics of the emission source,while numerical simulation is performed based on the measurement to test the capture efficiency and to further optimize various parameters including push velocity,hood height and exhaust air rate.Compared with the high-hanging hood,the low-hanging hood can effectively capture the pollutant generated by tyre with lower exhaust air rate.The capture efficiency of the low-hanging hood reaches 98.18%with exhaust air rate of 6000 m^(3)/h and push air velocity of 5m/s.The results indicates that the new ventilation appliance can effectively collect the pollutant at a relatively low exhaust rate.展开更多
基金This work was supported by the National Natural Science Foundation of China(31971690,31901357,and 31972453).
文摘Tree peony(Paeonia rockii)is an excellent woody oilseed crop,known for its highα-linolenic acid(ALA,∼45%)content,which is of great value for human health.However,the mechanisms underlying this high-level ALA accumulation in tree peony seeds are poorly understood.In this study,we evaluated the dynamic changes in the lipidomic profile of P.rockii seeds during development.A total of 760 lipid molecules were identified in P.rockii seeds;triacylglycerol(TAG)lipid molecules showed the highest abundance and diversity,both increasing during seed development.Particularly,ALA was the predominant fatty acid at the TAG sn-3 position.We further characterized two diacylglycerol acyltransferase(DGAT)genes and three phospholipid:diacylglycerol acyltransferase(PDAT)genes involved in the transfer of fatty acids to the TAG sn-3 position.Gene expression and subcellular localization analyses suggested that PrDGATs and PrPDATs may function as endoplasmic reticulum-localized proteins in seed TAG biosynthesis.In vitro functional complementation analysis showed different substrate specificities,with PrPDAT2 having a specific preference for ALA.Multiple biological assays demonstrated that PrDGAT1,PrDGAT2,PrPDAT1-2,and PrPDAT2 promote oil synthesis.Specifically,PrPDAT2 leads to preferential ALA in the oil.Our findings provide novel functional evidence of the roles of PrDGAT1 and PrPDAT2,which are potential targets for increasing the ALA yield in tree peony and other oilseed crops.
基金Project supported by the National Natural Science Foundation of China(Grant No.51901148)the Fund of the State Key Laboratory of Solidification Processing(Northwestern Polytechnical University),China(Grant No.SKLSP202006)the State Key Lab of Advanced Metals and Materials(University of Science and Technology Beijing),China(Grant No.2019-Z15).
文摘We simulate the evolution of hydrogen concentration and gas pore formation as equiaxed dendrites grow during solidification of a hypoeutectic aluminum-silicon(Al-Si)alloy.The applied lattice Boltzmann-cellular automaton-finite difference model incorporates the physical mechanisms of solute and hydrogen partitioning on the solid/liquid interface,as well as the transports of solute and hydrogen.After the quantitative validation by the simulation of capillary intrusion,the model is utilized to investigate the growth of the equiaxed dendrites and hydrogen porosity formation for an Al-(5 wt.%)Si alloy under different solidification conditions.The simulation data reveal that the gas pores favorably nucleate in the corners surrounded by the nearby dendrite arms.Then,the gas pores grow in a competitive mode.With the cooling rate increasing,the competition among different growing gas pores is found to be hindered,which accordingly increases the pore number density in the final solidification microstructure.In the late solidification stage,even though the solid fraction is increasing,the mean concentration of hydrogen in the residue melt tends to be constant,corresponding to a dynamic equilibrium state of hydrogen concentration in liquid.As the cooling rate increases or the initial hydrogen concentration decreases,the temperature of gas pore nucleation,the porosity fraction,and the mean porosity size decrease,whilst the mean hydrogen concentration in liquid increases in the late solidification stage.The simulated data present identical trends with the experimental results reported in literature.
文摘The chemical and physical characteristics of PM2.5, especially their temporal and geographical variations, have been explored in metropolitan Hangzhou area (China) by a field campaign from September 2010 to July 2011. Annual average concentrations of PM2.5 and PM10 during non-raining days were 106 - 131 μg.m-3 and 127 - 158 μg.m-3, respectively, at three stations in urban breathing zones, while corresponding concentrations of PM2.5 and PM10 at an urban background station (16 mabove ground level in a park) were 78 and 104 μg.m-3, respectively. For comparison, the annual average PM10 concentration at a suburban station (5 mAGL) was 93 μg.m-3. Detailed chemical analyses were also conducted for all samples collected during the campaign. We found that toxic metals (Cd, As, Pb, Zn, Mo, Cu, Hg) were highly enriched in the breathing zones due to anthropogenic activities, while soluble ions (, , ) and total carbon accounted for majority of PM2.5 mass. Unlike most areas in China where sulfate was several times of nitrate in fine PM, nitrate was as important as sulfate and highly correlated with ammonium during the campaign. Thus, a historical shift from sulfate-dominant fine PM to nitrate-dominant fine PM was documented.
基金A.Y.H. was supported by NRSA Institutional Postdoctoral Training grant T32 (Grant No. 5T32HL066987-20)C.S. was supported by grants from the National Natural Science Foundation of China (Grant No. 82001661)+1 种基金F.X.M. and C.S. were supported by the Haihe Laboratory of Cell Ecosystem Innovation Fund (Grant No. HH22KYZX0019)F.X.M. was supported by the National Natural Science Foundation of China (Grant No. 82171756)
文摘Neutrophils play an essential role in the defense against bacterial infections and orchestrate both the innate and adaptive immune responses.With their abundant numbers,diverse function and short life span,these cells are at the forefront of immune responses,and have gained attention in recent years because of their presence in tumor sites.Neutrophil involvement pertains to tumor cells'ability to construct a suitable tumor microenvironment(TME)that accelerates their own growth and malignancy,by facilitating their interaction with surrounding cells through the circulatory and lymphatic systems,thereby influencing tumor development and progression.Studies have indicated both pro-and anti-tumor properties of infiltrating neutrophils.The TME can exploit neutrophil function,recruitment,and even production,thus resulting in pro-tumor properties of neutrophils,including promotion of genetic instability,tumor cell proliferation,angiogenesis and suppression of anti-tumor or inflammatory response.In contrast,neutrophils can mediate anti-tumor resistance by direct cytotoxicity to the tumor cells or by facilitating anti-tumor functions via crosstalk with T cells.Here,we summarize current knowledge regarding the effects of neutrophil heterogeneity under homeostatic and tumor conditions,including neutrophil phenotype and function,in cancer biology.
基金National Natural Science Foundation of China(Grant No.52005357)“Qinglan”Project of Jiangsu Province of China,and Jiangsu Provincial Natural Science Foundation of China(Grant No.BK 20180984).
文摘Laser oscillating welding was employed to fabricate Al-Si coated press-hardened steel(PHS)to improve the element homogeneity in the fusion zone.Laser oscillating welding was employed with various oscillation amplitudes(0 mm,0.5 mm and 1.3 mm)in this present.Ni foil of 0.06 mm thickness was used as an interlayer between two tailored PHS welded.The weld morphology,elemental profile,microstructure and tensile strength of welded joints were studied.The results showed that full penetration weld without any weld defects were achieved for any oscillation amplitudes,and weld width increased with increasing oscillation amplitudes.With the oscillation amplitudes increased,Ni and Al had an uneven elemental profile due to strong stirring force,but the Ni and Al content in the weld was decreased and Ni had a sharp descent compared to Al element.Only fewδ-ferrite was presented in fusion line with the oscillation amplitudes increased to 1.3 mm.The oscillation amplitudes did not have an effect on the tensile properties,which was similar to that of base metal.But if keeping increasing the oscillation amplitudes or reducing the thickness of Ni interlayer,it has a potential risk to form more and moreδferrite such that deteriorate the mechnical properties of welded joints.
基金the Leading Talent Project of Special Support Plan of Guangdong Province[grant number 2019TX05N067]the special Projects in Key Fields of Colleges and Universities in Guangdong Province[grant numbers 2020ZDZX1001]+2 种基金the National Natural Science Foundation of China[grant numbers 42076133,42206127]the Science and Technology Project of Guangdong Province[grant number STKJ202209029,KTP20210376]the Guangdong Basic and Applied Basic Research Fund Regional Joint Fund-Youth Fund Project[grant number 2021A1515110514].
文摘The mud crab Scylla paramamosain is a key species in China due to its high nutritional value and great economic worth and has grown in popularity.Myo-inositol can modulate versatile physiological functions in aquatic animals.In the present study,S.paramamosain megalopa were given graded concentrations of myo-inositol(0,1,2,4,and 8 ppm)by water immersion to explore how their metamorphosis would be affected.The results showed that supplementing with myo-inositol remarkably increased transformation and survival rate from megalopa to crablet by at least 1.16 and 1.26 times,respectively.To decipher the molecular mechanism of how myo-inositol increases metamorphosis and survival rate,we further performed transcriptome-based gene expression profiling of both megalopa and crablet treated with myo-inositol.The integrative transcriptome analyses predicted that the differentially expressed genes(DEGs)were significantly enriched in chitinase activity,structural constituent of cuticle,and chitin binding,which are associated with the decomposition and reconstruction of cuticle.qPCR results confirmed that myo-inositol mediated gene expression levels of the above cuticle-related pathways.Considering the importance of the cuticle in exoskeleton formation and molting,it can be concluded that myo-inositol-induced changes in the cuticle decomposition and reconstruction might have accelerated the transformation from megalopa to crablet of S.paramamosain.Besides,numerous DEGs were significantly enriched in protein digestion and absorption,amino sugar and nucleotide sugar metabolism.It implies that myo-inositol may improve survival by regulating energy or nutrient absorption.Additionally,the accelerated metamorphosis by myo-inositol may improve survival from megalopa to crablet of S.paramamosain.Overall,this study will provide the first insights into the underlying molecular mechanisms by which myo-inositol increases metamorphosis and survival.
基金This work was partially supported by the China Scholarship Council(CSC)(No.201808080126)the Incubation Fund of Shandong Provincial Hospital(China)(No.2020FY019)+2 种基金the Young Scholars Program of Shandong Provincial Hospital,the Young Taishan Scholars Program of Shandong Province(China)(No.tsqn201909183)the Academic Promotion Program of Shandong First Medical University(China)(No.2020RC008)the Natural Science Foundation of Shandong Province(China)(No.ZR2020QH072 and ZR2021QH307).
文摘Due to the use of more adjuvant therapies and the increasing prevalence of associated diseases,nontraumatic osteonecrosis of the femoral head(ONFH)has become a substantial worldwide health issue;while glucocorticoid administration was the highest-ranked risk factor,with a proportion ranging from 26.35 to 55.75%.1 Albeit with similar radiological features,glucocorticoid-induced ONFH(GONFH)manifested a greater probability for advance-tolate-stage(post-collapse)lesions in comparison with its non-glucocorticoid-induced counterparts.i1 Therefore,an accurate and timely diagnosis of osteonecrosis following glucocorticoid therapy is of great significance to initiate nonoperative treatment regimens or joint-preserving procedures,slow disease progression,and defer or avert joint arthroplasty.
基金supported by the National Natural Science Foundation of China (No. 21577125)the Social Development Special Fund from Science and Technology Bureau of Hangzhou, China (No. 20110533B09)
文摘In this study, the influences of accumulated mileage(deterioration) and technological changes(emission standards) on emission factors(EFs) of regulated pollutants(CO, HC, and NO_x) from gasoline passenger vehicles were investigated based on Inspection and Maintenance(I/M) data using the chassis dynamometer method. The accumulated mileage of passenger vehicles was significantly linearly correlated with vehicle age. For most cases,the average EFs of CO, HC and NO_x were significantly linearly correlated with accumulated mileage, indicating that emission deterioration had a significant impact on pollutant EFs.Implemented emission standards markedly influenced the EFs of regulated pollutants, and EFs markedly decreased with progressing emission standards. The present study also compared EFs of regulated pollutants between this study and the International vehicle emission(IVE) model, and marked differences in EFs were seen with variations in emission standards, vehicle types and accumulated mileage; NO_x EFs in this study were higher than in the IVE model. The results provide new insight into estimating regulated pollutant emissions using the IVE model.
基金supported by the International Cooperation Project of MOST(No.2012DFG90290)the National Natural Science Foundation of China(No.4225001046)+1 种基金National Department Public Benefit Research Foundation(No.201509014)the Basic Foundation for Public Benefit-Research Academies from Centre Government(No.2010KYYW02)
文摘Gaseous peroxides play important roles in atmospheric chemistry. To understand the pathways of the formation and removal of peroxides, atmospheric peroxide concentrations and their controlling factors were measured from 7:00 to 20:00 in September, October, and November 2013 at a heavily trafficked residential site in Beijing, China, with average concentrations of hydrogen peroxide(H_2O_2) and methyl hydroperoxide(MHP) at 0.55 ppb and 0.063 ppb, respectively. H_2O_2 concentrations were higher in the afternoon and lower in the morning and evening, while MHP concentrations did not exhibit a regular diurnal pattern. Both H_2O_2 and MHP concentrations increased at dusk in most cases. Both peroxides displayed monthly variations with higher concentrations in September. These results suggested that photochemical activity was the main controlling factor on variations of H_2O_2 concentrations during the measurement period. Increasing concentrations of volatile organic compounds emitted by motor vehicles were important contributors to H_2O_2 and MHP enrichment. High levels of H_2O_2 and MHP concentrations which occurred during the measurement period probably resulted from the transport of a polluted air mass with high water vapor content passing over the Bohai Bay, China.
文摘To cope with an increasingly turbulent environment,manufacturing firms increasingly implement integration practices to enhance flexibility in the production process.This research develops a framework to explore the relationships among organizational integration practices,manufacturing flexibility,and competitive advantage.The study develops valid and reliable instruments to measure these constructs,and it applies structural equation modeling to test relationships among these variables using a large sample.The results indicate strong,positive,and direct relationships between organizational integration practices and manufacturing flexibility,and between manufacturing flexibility and competitive advantage.The results also indicate that organizational integration practices enhance competitive advantage directly as well as indirectly by facilitating manufacturing flexibility.
基金the Beijing Natural Science Foundation(No.7182146)the Biomedical Translational Engineering Research Center of BUCT-CJFH(No.RZ2020–02)+3 种基金the National Natural Science Foundation of China(No.82072524)the Young Taishan Scholars Program of Shandong Province(No.tsqn201909183)the Academic promotion program of Shandong First Medical University(No.2020RC008)the Natural Science Foundation of Shandong Province(No.ZR201911090016)。
文摘Osteonecrosis of the femoral head(ONFH)is a devastating musculoskeletal disease characterized by the impaired circulation of bone.The purpose of this study was to explore the underlying mechanisms of the protective effect of icariin on the glucocorticoid-induced injury of bone microvascular endothelial cells(BMECs).Normal BMECs were extracted from the femoral heads by enzymatic isolation and magneticactivated cell sorting methods.Dexamethasone and icariin were used to intervene BMECs in microfluidic organ chips,and phalloidin staining was conducted to observe the cell morphology and viability.Then next-generation transcriptome sequencing and real-time quantitative reverse transcription-polymerase chain reaction(q RT-PCR)were performed to identify the differentially expressed genes(DEGs)in different groups.Through the microfluidic organ chip,it can be observed that after dexamethasone intervention,the filamentous structure in cell fibers disappeared and the cell morphology changed from spindle to round until death.Icariin could relieve these changes and showed a protective effect on glucocorticoiddamaged BMECs.In addition,201 DEGs were detected between the icariin protection group and the dexamethasone group,which were significantly enriched in 17 signaling pathways.8 of the top ten selected hub genes(IL6,PTGS2,VEGFA,etc.)were confirmed by q RT-PCR.Transcription factors(TFs)-gene network showed 63 connections between 18 TFs and 12 DEGs.For instance,GATA2 could regulate 5 DEGs.The associations between 92 mi RNA and 12 DEGs were visualized in a mi RNA-gene network.The hub mi RNA,has-mir-335–5 p was predicted to interact with 8 DEGs(PTGS2,VEGFA,etc.).Microfluidic organ chips could provide excellent morphological results for cell experiments,by which it could be observed that icariin showed a protective effect on the glucocorticoid-induced injury of BMECs.Beside,these DEGs,possible regulatory TF(GATA2,FOXC1,etc.)and mi RNA(has-mir-335–5 p)might be dysregulated in the initiation of ONFH and have prospective importance in ONFH diagnosis and therapy.
文摘This paper proposes a push-pull airflow combined with a top draft hood to conduct local exhaust in a rubber workshop.Field measurements are carried out to investigate the characteristics of the emission source,while numerical simulation is performed based on the measurement to test the capture efficiency and to further optimize various parameters including push velocity,hood height and exhaust air rate.Compared with the high-hanging hood,the low-hanging hood can effectively capture the pollutant generated by tyre with lower exhaust air rate.The capture efficiency of the low-hanging hood reaches 98.18%with exhaust air rate of 6000 m^(3)/h and push air velocity of 5m/s.The results indicates that the new ventilation appliance can effectively collect the pollutant at a relatively low exhaust rate.