Background Abdominal fat deposition depends on both the proliferation of preadipocytes and their maturation into adipocytes,which is a well-orchestrated multistep process involving many regulatory molecules.Circular R...Background Abdominal fat deposition depends on both the proliferation of preadipocytes and their maturation into adipocytes,which is a well-orchestrated multistep process involving many regulatory molecules.Circular RNAs(circRNAs)have emergingly been implicated in mammalian adipogenesis.However,circRNA-mediated regulation in chicken adipogenesis remains unclear.Our previous circRNA sequencing data identified a differentially expressed novel circRNA,8:27,886,180|27,889,657,during the adipogenic differentiation of chicken abdominal preadipocytes.This study aimed to investigate the regulatory role of circDOCK7 in the proliferation and adipogenic differentiation of chicken abdominal preadipocytes,and explore its molecular mechanisms of competing endogenous RNA underlying chicken adipogenesis.Results Our results showed that 8:27,886,180|27,889,657 is an exonic circRNA derived from the head-to-tail splicing of exons 19–22 of the dedicator of cytokinesis 7(DOCK7)gene,abbreviated as circDOCK7.CircDOCK7 is mainly distributed in the cytoplasm of chicken abdominal preadipocytes and is stable because of its RNase R resistance and longer half-life.CircDOCK7 is significantly upregulated in the abdominal fat tissues of fat chickens compared to lean chickens,and its expression gradually increases during the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Functionally,the gain-and loss-of-function experiments showed that circDOCK7 promoted proliferation,G0/G1-to S-phase progression,and glucose uptake capacity of chicken abdominal preadipocytes,in parallel with adipogenic differentiation characterized by remarkably increased intracellular lipid droplet accumulation and triglyceride and acetyl coenzyme A content in differentiated chicken abdominal preadipocytes.Mechanistically,a pull-down assay and a dual-luciferase reporter assay confirmed that circDOCK7 interacted with gga-miR-301b-3p,which was identified as an inhibitor of chicken abdominal adipogenesis.Moreover,the ACSL1 gene was demonstrated to be a direct target of gga-miR-301b-3p.Chicken ACSL1 protein is localized in the endoplasmic reticulum and mitochondria of chicken abdominal preadipocytes and acts as an adipogenesis accelerator.Rescue experiments showed that circDOCK7 could counteract the inhibitory effects of gga-miR-301b-3p on ACSL1 mRNA abundance as well as the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Conclusions CircDOCK7 serves as a miRNA sponge that directly sequesters gga-miR-301b-3p away from the ACSL1 gene,thus augmenting adipogenesis in chickens.These findings may elucidate a new regulatory mechanism underlying abdominal fat deposition in chickens.展开更多
Potato(Solanum tuberosum L.)is susceptible to enzymatic browning after fresh processing,resulting in color change and potential alteration in the nutritional quality.In this study,a popular potato cultivar,Feiwuruita,...Potato(Solanum tuberosum L.)is susceptible to enzymatic browning after fresh processing,resulting in color change and potential alteration in the nutritional quality.In this study,a popular potato cultivar,Feiwuruita,was used to profile the metabolites involved in color and nutritional quality changes in fresh shreds stored at 0 and 4 h at 25°C(designated CK and CK4H,respectively).The shreds turned brown within 4 h of storage.In all,723 metabolites consisting 12 classes of compounds were detected in the samples,largely lipids,phenolic acids,alkaloids,amino acids and derivatives,flavonoids,organic acids,nucleotides and derivatives.Of these,163 metabolites accumulated differentially between CK and CK4H shreds.Polyphenolic compounds(phenolic acids and flavonoids)mostly increased in the shreds after 4 h storage.Conversely,the short-term storage drastically reduced lipid compounds(25 LysoPC and 19 LysoPE),while essential alkaloids and terpenoid compounds that are beneficial to human health increased in accumulation.The findings present global metabolome and nutritional composition changes in short-term stored shreds of Feiwuruita.This study provides important foundation for future studies on browning prevention/reduction and for better utilization of Feiwuruita.展开更多
We investigated the influence of the growth temperature, O_(2) flow, molar ratio between Ga_(2)O_(3) powder and graphite powder on the structure and morphology of the films grown on the c-plane sapphire(0001) substrat...We investigated the influence of the growth temperature, O_(2) flow, molar ratio between Ga_(2)O_(3) powder and graphite powder on the structure and morphology of the films grown on the c-plane sapphire(0001) substrates by a carbothermal reduction method. Experimental results for the heteroepitaxial growth of β-Ga_(2)O_(3) illustrate that β-Ga_(2)O_(3) growth by the carbothermal reduction method can be controlled. The optimal result was obtained at a growth temperature of 1050 °C. The fastest growth rate of β-Ga_(2)O_(3) films was produced when the O_(2) flow was 20 sccm. To guarantee that β-Ga_(2)O_(3) films with both high-quality crystal and morphology properties, the ideal molar ratio between graphite powder and Ga_(2)O_(3) powder should be set at 10 : 1.展开更多
Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capa...Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capacity were examined. The maximum adsorption capacity of 1689 mg/g was observed at an initial p H value of 3.5 after agitating for 10 min. It was demonstrated that polyvinylpyrrolidone-reduced graphene oxide had a huge adsorption capacity for Cu ions, which was 10 times higher than maximal value reported in previous works. The adsorption mechanism was also discussed by density functional theory. It demonstrates that Cu ions are attracted to surface of reduced graphene oxide by C atoms in reduced graphene oxide modified by polyvinylpyrrolidone through physisorption processes, which may be responsible for the higher adsorption capacity. Our results suggest that polyvinylpyrrolidone-reduced graphene oxide is an effective adsorbent for removing Cu ions in wastewater. It also provides a new way to improve the adsorption capacity of reduced graphene oxide for dealing with the heavy metal ion in wastewater.展开更多
This study aims to investigate the protective roles of photosynthetic characteristics and antioxidative systems in the desiccation tolerance of Sophora moorcroftiana and Caragana maximovicziana as they adapt to arid e...This study aims to investigate the protective roles of photosynthetic characteristics and antioxidative systems in the desiccation tolerance of Sophora moorcroftiana and Caragana maximovicziana as they adapt to arid environments. A variety of physiological and biochemical parameters in the leaves of two Leguminosae species were monitored for 1, 7, 14, 21 and 28 d of drought stress. Soil water content decreased from 38.58% to 7.33% after exposure to 28 d of water stress. The photosynthetic carbon-assimilation rates of the two Leguminosae plants decreased for non-stomatal limitation with processing water stress. The malondialdehyde content and cell membrane relative conductivity of the two species increased significantly from 1 to 21 d and then decreased. S. moorcroftiana showed higher superoxide dismutase and peroxidase activities than C. maximovicziana during the 28 d treatment period. However, the catalase activities and proline content of C. maximovicziana were higher than those of S. moorcroftiana before the water stress treatment reached 21 d. Nine physiological and biochemical parameters were selected to comprehensively evaluate the two species' drought-resistance by the membership function values(MFV). The mean MFV indicated that S. moorcroftiana has a relatively stronger drought defense capability than C. maximovicziana. S. moorcroftiana mainly uses carbon-assimilation rate and osmotic adjustment to combat water deficiency.展开更多
Brassinosteroids(BRs) are a class of plant-specific steroidal hormones that play important roles in multiple biological processes. In this paper, a classic rice mutant gsor300084,showing erect leaves and semi-dwarf st...Brassinosteroids(BRs) are a class of plant-specific steroidal hormones that play important roles in multiple biological processes. In this paper, a classic rice mutant gsor300084,showing erect leaves and semi-dwarf stature, was characterized. Morphological analysis in darkness showed that the mesocotyl of the gsor300084 mutant did not elongate when grown in darkness. Coleoptile elongation and root growth were less affected by the exogenous application of brassinolide(BL), the most active form of BR, in gsor300084 than in the wild-type rice variety Matsumae. Lamina joint bending analysis also showed that gsor300084 was less sensitive to exogenous BL than Matsumae. These results suggested that the gsor300084 mutant is defective in BR sensitivity. Map-based cloning indicated that gsor300084 is a novel allelic mutant of the DWARF61(D61) gene, which encodes the putative BR receptor OsBRI1. A single-base mutation appears in the LRR domain of OsBRI1, changing the 444 th amino acid from tryptophan(W) to arginine(R). Subcellular localization analysis suggested that both the wild-type and mutant OsBRI1 protein are localized at the cytoplasmic membrane. Structure modeling revealed that the W444 R substitution may affect the perception of BRs by the LRR domain.展开更多
This study describes the treatment of composting leachate by the combination of coagulation and nanofiltration process.Poly ferric sulfate(PSF) was used as coagulant,and the effect of p H value and PSF dosage on the c...This study describes the treatment of composting leachate by the combination of coagulation and nanofiltration process.Poly ferric sulfate(PSF) was used as coagulant,and the effect of p H value and PSF dosage on the coagulation performance was investigated.The results indicated that the chemical oxidation demand(COD)and turbidity removal efficiency could reach to 62.8% and 75.3%,respectively at an optimum dosage of1200 mg·L^(-1)at p H 6.0.During the nanofiltration process,the operation conditions such as temperature and pressure were optimized,89.7% of COD,78.2% of TOC,72.5% of TN,83.2% of TP,and 78.6% of NH3-N were retained when tested at 0.6 MPa at 25 °C.The final leachate effluent concentration of COD,BOD5,NH3-N,TOC,SS was92 mg·L^(-1),31 mg·L^(-1),21 mg·L^(-1),73 mg·L^(-1)and 23 mg·L^(-1),respectively,which reached the local discharge standard.The combination of coagulation-filtration is useful for composting leachate treatment.展开更多
While phthalate acid esters(PAEs)cannot fluoresce alone,they can be detected by fluorescence spectroscopy after chelation with bovine serum albumin(BSA).In this study,the types of amino acid residues at the active sit...While phthalate acid esters(PAEs)cannot fluoresce alone,they can be detected by fluorescence spectroscopy after chelation with bovine serum albumin(BSA).In this study,the types of amino acid residues at the active site of PAEs chelated with BSA were determined using molecular docking technology.A modification scheme of BSA with higher detection sensitivity fluorescence spectroscopy for PAEs was proposed based on the docking results and constructed for a novel BSA structure with a higher detection sensitivity of fluorescence spectroscopy using a homologous modeling method.Density functional theory(DFT)was employed to explore the influence before and after BSA modification on PAEs’detection through fluorescence spectroscopy.The results showed that the docking scores between BSAs and dimethyl phthalate(DMP),dibutyl phthalate(DBP)and di-n-octyl phthalate(DNOP)were increased up to 26.45%,16.82%and 16.30%,respectively,indicating that the active site modification of BSA could enhance the binding affinity between BSA and PAEs.The fluorescence intensity of PAEs chelated with modified BSAs were calculated.The fluorescence intensity of fluorescence spectroscopy for DMP,DBP and DNOP chelated with BSAs after modification was increased up to 2.8-,104.51-and 62.43-fold,respectively,which achieved the purpose of theoretically modifying BSA to improve the detection sensitivity of fluorescence spectroscopy for PAEs.展开更多
Mass transport is crucial to the performance of proton exchange membrane fuel cells,especially at high current densities.Generally,the oxygen and the generated water share same transmission medium but move towards opp...Mass transport is crucial to the performance of proton exchange membrane fuel cells,especially at high current densities.Generally,the oxygen and the generated water share same transmission medium but move towards opposite direction,which leads to serious mass transfer problems.Herein,a series of patterned catalyst layer were prepared with a simple one-step impressing method using nylon sieves as templates.With grooves 100μm in width and 8μm in depth on the surface of cathode catalyst layer,the maximum power density of fuel cell increases by 10%without any additional durability loss while maintaining a similar electrochemical surface area.The concentration contours calculated by finite element analysis reveal that the grooves built on the surface of catalyst layer serve to accumulate the water nearby while oxygen tends to transfer through relatively convex region,which results from capillary pressure difference caused by the pore structure difference between the two regions.The separation of oxidant gas and generated water avoids mass confliction thus boosts mass transport efficiency.展开更多
Simulation models for accident section on freeway are built in microscopic traffic flow simulation environment. In these models involving 2-lane,3-lane and 4-lane freeway,one detector is set every 10 m to measure sect...Simulation models for accident section on freeway are built in microscopic traffic flow simulation environment. In these models involving 2-lane,3-lane and 4-lane freeway,one detector is set every 10 m to measure section running speed. According to the simulation results,speed spatial distribution curves for traffic accident section on freeway are drawn which help to determine dangerous sections on upstream of accident section. Furthermore,the speed spatial distribution models are obtained for every speed distribution curve. The results provide theoretical basis for determination on temporal and spatial influence ranges of traffic accident and offer reference to formulation of speed limit scheme and other management measures.展开更多
In order to improve the condition monitoring and fault diagnosis of wind turbines,a stacked noise reduction autoencoding network based on group normalization is proposed in this paper.The network is based on SCADA dat...In order to improve the condition monitoring and fault diagnosis of wind turbines,a stacked noise reduction autoencoding network based on group normalization is proposed in this paper.The network is based on SCADA data of wind turbine operation,firstly,the group normalization(GN)algorithm is added to solve the problems of stack noise reduction autoencoding network training and slow convergence speed,and the RMSProp algorithm is used to update the weight and the bias of the autoenccoder,which further optimizes the problem that the loss function swings too much during the update process.Finally,in the last layer of the network,the softmax activation function is used to classify the results,and the output of the network is transformed into a probability distribution.The selected wind turbine SCADA data was substituted into the pre-improved and improved stacked denoising autoencoding(SDA)networks for comparative training and verification.The results show that the stacked denoising autoencoding network based on group normalization is more accurate and effective for wind turbine condition monitoring and fault diagnosis,and also provides a reference for wind turbine fault identification.展开更多
Gut microbiota and circulating metabolite dysbiosis predate important pathological changes in glucose metabolic disorders;however,comprehensive studies on impaired glucose tolerance(IGT),a diabetes mellitus(DM)precurs...Gut microbiota and circulating metabolite dysbiosis predate important pathological changes in glucose metabolic disorders;however,comprehensive studies on impaired glucose tolerance(IGT),a diabetes mellitus(DM)precursor,are lacking.Here,we perform metagenomic sequencing and metabolomics on 47 pairs of individuals with IGT and newly diagnosed DM and 46 controls with normal glucose tolerance(NGT);patients with IGT are followed up after 4 years for progression to DM.Analysis of baseline data reveals significant differences in gut microbiota and serum metabolites among the IGT,DM,and NGT groups.In addition,13 types of gut microbiota and 17 types of circulating metabolites showed significant differences at baseline before IGT progressed to DM,including higher levels of Eggerthella unclassified,Coprobacillus unclassified,Clostridium ramosum,L-valine,L-norleucine,and L-isoleucine,and lower levels of Eubacterium eligens,Bacteroides faecis,Lachnospiraceae bacterium 3_1_46FAA,Alistipes senegalensis,Megaspaera elsdenii,Clostridium perfringens,α-linolenic acid,10E,12Z-octadecadienoic acid,and dodecanoic acid.A random forest model based on differential intestinal microbiota and circulating metabolites can predict the progression from IGT to DM(AUC=0.87).These results suggest that microbiome and metabolome dysbiosis occur in individuals with IGT and have important predictive values and potential for intervention in preventing IGT from progressing to DM.展开更多
Background:Accumulating evidence suggests that metabolic disorders,including type 2 diabetes mellitus(T2DM),can be treated with traditional Chinese medicine formulas,such as the Gegen Qinlian decoction(GQD).This study...Background:Accumulating evidence suggests that metabolic disorders,including type 2 diabetes mellitus(T2DM),can be treated with traditional Chinese medicine formulas,such as the Gegen Qinlian decoction(GQD).This study elucidates the mechanisms by which gut microbes mediate the anti-diabetic effects of GQD.Methods:We conducted a double-blind randomized clinical trial involving 120 untreated participants with T2DM.During the 12-week intervention,anthropometric measurements and diabetic traits were recorded every 4 weeks.Fecal microbiota and serum metabolites were measured before and after the intervention using 16S rDNA sequencing,liquid chromatography-mass spectrometry,and Bio-Plex panels.Results:Anti-diabetic effects were observed in the GQD group in the human trial.Specifically,glycated hemoglobin,fasting plasma glucose,and two-hour postprandial blood glucose levels were significantly lower in the GQD group than in the placebo group.Additionally,Faecalibacterium was significantly enriched in the GQD group,and the short-chain fatty acid levels were higher and the serum inflammation-associated marker levels were lower in the GQD group compared to the placebo group.Moreover,Faecalibacterium abundance negatively correlated with the levels of serum hemoglobin,fasting plasma glucose,and pro-inflammatory cytokines.Finally,the diabetes-alleviating effect of Faecalibacterium was confirmed by oral administration of Faecalibacterium prausnitzi(DSMZ 17677)in T2DMmousemodel.Conclusions:GQD improved type 2 diabetes primarily by modulating the abundance of Faecalibacterium in the gut microbiota,alleviating metabolic disorders and the inflammatory state.展开更多
The use of fossil fuels results in significant carbon dioxide emissions.Biofuels have been increasingly adopted as sustainable alternatives to fossil fuel to address this environmental issue.Integrating petroleum refi...The use of fossil fuels results in significant carbon dioxide emissions.Biofuels have been increasingly adopted as sustainable alternatives to fossil fuel to address this environmental issue.Integrating petroleum refineries into biofuel supply chains is an effective approach to mitigating greenhouse gas emissions and improving environmental sustainability.In this study,an integrated supply chain optimization framework was established,considering the carbon trade policy.In addition,a mixed-integer nonlinear programming model was developed to optimize the selection of biomass suppliers,construction of pretreatment plants and biorefineries,integration of petroleum refineries,and selection of transportation routes with the objective of minimizing the total annual cost.An example is presented to illustrate the applicability of the model.The optimization results show that integrating petroleum refineries into biofuel supply chains effectively mitigates carbon emissions.Carbon trade policies can have a direct impact on the total annual cost and carbon emissions of the supply chain.展开更多
Separation of propane from natural gas is of great importance to industry.However,in light of size-based separation,there still lacks effective method to directly separate propane from natural gas,due to the comparabl...Separation of propane from natural gas is of great importance to industry.However,in light of size-based separation,there still lacks effective method to directly separate propane from natural gas,due to the comparable physical properties for these light alkanes(C1–C4)and the middle size of propane.In this work,we found that a new Th-metal-organic framework(MOF)could be an ideal solution for this issue.The Th-MOF takes UiO-66-type structure,but with the pocket sealed by six-fold imide groups;this not only precisely reduces the size of pocket to exactly match propane,but also enhances the host–guest interactions through multiple(C)H(^(δ+))∙∙∙(^(δ−))O(C)interactions.As a result,highly selective adsorption of propane over methane,ethane,and butane was observed,implying unique middle-size separation.The actual separation was confirmed by breakthrough experiments of simulated natural gas,confirming its superior application in direct separation of propane from natural gas.The separation mechanism,as unveiled by both theoretical calculation and comparative experiments,is due to the six-fold imide-sealed pocket that could effectively distinguish propane from other light alkanes through both size effect and host–guest interactions.展开更多
基金the National Key Research and Development Program of China(2021YFD1200803 and 2022YFD1600902)China Agriculture Research System(CARS-40).
文摘Background Abdominal fat deposition depends on both the proliferation of preadipocytes and their maturation into adipocytes,which is a well-orchestrated multistep process involving many regulatory molecules.Circular RNAs(circRNAs)have emergingly been implicated in mammalian adipogenesis.However,circRNA-mediated regulation in chicken adipogenesis remains unclear.Our previous circRNA sequencing data identified a differentially expressed novel circRNA,8:27,886,180|27,889,657,during the adipogenic differentiation of chicken abdominal preadipocytes.This study aimed to investigate the regulatory role of circDOCK7 in the proliferation and adipogenic differentiation of chicken abdominal preadipocytes,and explore its molecular mechanisms of competing endogenous RNA underlying chicken adipogenesis.Results Our results showed that 8:27,886,180|27,889,657 is an exonic circRNA derived from the head-to-tail splicing of exons 19–22 of the dedicator of cytokinesis 7(DOCK7)gene,abbreviated as circDOCK7.CircDOCK7 is mainly distributed in the cytoplasm of chicken abdominal preadipocytes and is stable because of its RNase R resistance and longer half-life.CircDOCK7 is significantly upregulated in the abdominal fat tissues of fat chickens compared to lean chickens,and its expression gradually increases during the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Functionally,the gain-and loss-of-function experiments showed that circDOCK7 promoted proliferation,G0/G1-to S-phase progression,and glucose uptake capacity of chicken abdominal preadipocytes,in parallel with adipogenic differentiation characterized by remarkably increased intracellular lipid droplet accumulation and triglyceride and acetyl coenzyme A content in differentiated chicken abdominal preadipocytes.Mechanistically,a pull-down assay and a dual-luciferase reporter assay confirmed that circDOCK7 interacted with gga-miR-301b-3p,which was identified as an inhibitor of chicken abdominal adipogenesis.Moreover,the ACSL1 gene was demonstrated to be a direct target of gga-miR-301b-3p.Chicken ACSL1 protein is localized in the endoplasmic reticulum and mitochondria of chicken abdominal preadipocytes and acts as an adipogenesis accelerator.Rescue experiments showed that circDOCK7 could counteract the inhibitory effects of gga-miR-301b-3p on ACSL1 mRNA abundance as well as the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Conclusions CircDOCK7 serves as a miRNA sponge that directly sequesters gga-miR-301b-3p away from the ACSL1 gene,thus augmenting adipogenesis in chickens.These findings may elucidate a new regulatory mechanism underlying abdominal fat deposition in chickens.
基金research was funded by Major Science and Technology Project of Xiamen,China(3502Z20211004)Xiamen Science and Technology Assistance Project(3502Z20194509,3502Z20204504-2,3502Z20204501-3).
文摘Potato(Solanum tuberosum L.)is susceptible to enzymatic browning after fresh processing,resulting in color change and potential alteration in the nutritional quality.In this study,a popular potato cultivar,Feiwuruita,was used to profile the metabolites involved in color and nutritional quality changes in fresh shreds stored at 0 and 4 h at 25°C(designated CK and CK4H,respectively).The shreds turned brown within 4 h of storage.In all,723 metabolites consisting 12 classes of compounds were detected in the samples,largely lipids,phenolic acids,alkaloids,amino acids and derivatives,flavonoids,organic acids,nucleotides and derivatives.Of these,163 metabolites accumulated differentially between CK and CK4H shreds.Polyphenolic compounds(phenolic acids and flavonoids)mostly increased in the shreds after 4 h storage.Conversely,the short-term storage drastically reduced lipid compounds(25 LysoPC and 19 LysoPE),while essential alkaloids and terpenoid compounds that are beneficial to human health increased in accumulation.The findings present global metabolome and nutritional composition changes in short-term stored shreds of Feiwuruita.This study provides important foundation for future studies on browning prevention/reduction and for better utilization of Feiwuruita.
基金supported by the National Natural Science Foundation of China under Grant 62104024, Grant 11875097, Grant 12075045, Grant 11975257, Grant 11961141014, and Grant 62074146the Fundamental Research Funds for the Central Universities under Grant DUT19RC (3)074the Natural Science Foundation of Liaoning Province under Grant 2021MS124, Grant 2022020474JH2/1013。
文摘We investigated the influence of the growth temperature, O_(2) flow, molar ratio between Ga_(2)O_(3) powder and graphite powder on the structure and morphology of the films grown on the c-plane sapphire(0001) substrates by a carbothermal reduction method. Experimental results for the heteroepitaxial growth of β-Ga_(2)O_(3) illustrate that β-Ga_(2)O_(3) growth by the carbothermal reduction method can be controlled. The optimal result was obtained at a growth temperature of 1050 °C. The fastest growth rate of β-Ga_(2)O_(3) films was produced when the O_(2) flow was 20 sccm. To guarantee that β-Ga_(2)O_(3) films with both high-quality crystal and morphology properties, the ideal molar ratio between graphite powder and Ga_(2)O_(3) powder should be set at 10 : 1.
基金the support by National Natural Science Foundation of China under grants (11202006)University’s Science and technology exploiture of Shangxi Province (20121010)the National Basic Research Program of China (G2010CB832701)
文摘Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capacity were examined. The maximum adsorption capacity of 1689 mg/g was observed at an initial p H value of 3.5 after agitating for 10 min. It was demonstrated that polyvinylpyrrolidone-reduced graphene oxide had a huge adsorption capacity for Cu ions, which was 10 times higher than maximal value reported in previous works. The adsorption mechanism was also discussed by density functional theory. It demonstrates that Cu ions are attracted to surface of reduced graphene oxide by C atoms in reduced graphene oxide modified by polyvinylpyrrolidone through physisorption processes, which may be responsible for the higher adsorption capacity. Our results suggest that polyvinylpyrrolidone-reduced graphene oxide is an effective adsorbent for removing Cu ions in wastewater. It also provides a new way to improve the adsorption capacity of reduced graphene oxide for dealing with the heavy metal ion in wastewater.
基金sponsored by the National Natural Science Foundation of China (31260189)
文摘This study aims to investigate the protective roles of photosynthetic characteristics and antioxidative systems in the desiccation tolerance of Sophora moorcroftiana and Caragana maximovicziana as they adapt to arid environments. A variety of physiological and biochemical parameters in the leaves of two Leguminosae species were monitored for 1, 7, 14, 21 and 28 d of drought stress. Soil water content decreased from 38.58% to 7.33% after exposure to 28 d of water stress. The photosynthetic carbon-assimilation rates of the two Leguminosae plants decreased for non-stomatal limitation with processing water stress. The malondialdehyde content and cell membrane relative conductivity of the two species increased significantly from 1 to 21 d and then decreased. S. moorcroftiana showed higher superoxide dismutase and peroxidase activities than C. maximovicziana during the 28 d treatment period. However, the catalase activities and proline content of C. maximovicziana were higher than those of S. moorcroftiana before the water stress treatment reached 21 d. Nine physiological and biochemical parameters were selected to comprehensively evaluate the two species' drought-resistance by the membership function values(MFV). The mean MFV indicated that S. moorcroftiana has a relatively stronger drought defense capability than C. maximovicziana. S. moorcroftiana mainly uses carbon-assimilation rate and osmotic adjustment to combat water deficiency.
基金supported by grants from the Ministry of Science and Technology of China(Grant No.2013CBA01401)the Ministry of Agriculture of China(Grant No.2011ZX08009-003)the Agricultural Science and Technology Innovation Program of China
文摘Brassinosteroids(BRs) are a class of plant-specific steroidal hormones that play important roles in multiple biological processes. In this paper, a classic rice mutant gsor300084,showing erect leaves and semi-dwarf stature, was characterized. Morphological analysis in darkness showed that the mesocotyl of the gsor300084 mutant did not elongate when grown in darkness. Coleoptile elongation and root growth were less affected by the exogenous application of brassinolide(BL), the most active form of BR, in gsor300084 than in the wild-type rice variety Matsumae. Lamina joint bending analysis also showed that gsor300084 was less sensitive to exogenous BL than Matsumae. These results suggested that the gsor300084 mutant is defective in BR sensitivity. Map-based cloning indicated that gsor300084 is a novel allelic mutant of the DWARF61(D61) gene, which encodes the putative BR receptor OsBRI1. A single-base mutation appears in the LRR domain of OsBRI1, changing the 444 th amino acid from tryptophan(W) to arginine(R). Subcellular localization analysis suggested that both the wild-type and mutant OsBRI1 protein are localized at the cytoplasmic membrane. Structure modeling revealed that the W444 R substitution may affect the perception of BRs by the LRR domain.
基金Supported by the Natural Science Foundation of Zhejiang Province(LQ14B060001,Y14F030005)Foundation of Science and Technology Department of Zhejiang Province of China(2013C33019,2015C33232)Science and Technology Project of Lishui City(2015RC23)
文摘This study describes the treatment of composting leachate by the combination of coagulation and nanofiltration process.Poly ferric sulfate(PSF) was used as coagulant,and the effect of p H value and PSF dosage on the coagulation performance was investigated.The results indicated that the chemical oxidation demand(COD)and turbidity removal efficiency could reach to 62.8% and 75.3%,respectively at an optimum dosage of1200 mg·L^(-1)at p H 6.0.During the nanofiltration process,the operation conditions such as temperature and pressure were optimized,89.7% of COD,78.2% of TOC,72.5% of TN,83.2% of TP,and 78.6% of NH3-N were retained when tested at 0.6 MPa at 25 °C.The final leachate effluent concentration of COD,BOD5,NH3-N,TOC,SS was92 mg·L^(-1),31 mg·L^(-1),21 mg·L^(-1),73 mg·L^(-1)and 23 mg·L^(-1),respectively,which reached the local discharge standard.The combination of coagulation-filtration is useful for composting leachate treatment.
文摘While phthalate acid esters(PAEs)cannot fluoresce alone,they can be detected by fluorescence spectroscopy after chelation with bovine serum albumin(BSA).In this study,the types of amino acid residues at the active site of PAEs chelated with BSA were determined using molecular docking technology.A modification scheme of BSA with higher detection sensitivity fluorescence spectroscopy for PAEs was proposed based on the docking results and constructed for a novel BSA structure with a higher detection sensitivity of fluorescence spectroscopy using a homologous modeling method.Density functional theory(DFT)was employed to explore the influence before and after BSA modification on PAEs’detection through fluorescence spectroscopy.The results showed that the docking scores between BSAs and dimethyl phthalate(DMP),dibutyl phthalate(DBP)and di-n-octyl phthalate(DNOP)were increased up to 26.45%,16.82%and 16.30%,respectively,indicating that the active site modification of BSA could enhance the binding affinity between BSA and PAEs.The fluorescence intensity of PAEs chelated with modified BSAs were calculated.The fluorescence intensity of fluorescence spectroscopy for DMP,DBP and DNOP chelated with BSAs after modification was increased up to 2.8-,104.51-and 62.43-fold,respectively,which achieved the purpose of theoretically modifying BSA to improve the detection sensitivity of fluorescence spectroscopy for PAEs.
基金supported by the National Natural Science Foundation of China(21838003,91834301)the Shanghai Scientific and Technological Innovation Project(18JC1410600,19JC1410400)+2 种基金the Social Development Program of Shanghai(17DZ1200900)the Innovation Program of Shanghai Municipal Education Commissionthe Fundamental Research Funds for the Central Universities(222201718002)。
文摘Mass transport is crucial to the performance of proton exchange membrane fuel cells,especially at high current densities.Generally,the oxygen and the generated water share same transmission medium but move towards opposite direction,which leads to serious mass transfer problems.Herein,a series of patterned catalyst layer were prepared with a simple one-step impressing method using nylon sieves as templates.With grooves 100μm in width and 8μm in depth on the surface of cathode catalyst layer,the maximum power density of fuel cell increases by 10%without any additional durability loss while maintaining a similar electrochemical surface area.The concentration contours calculated by finite element analysis reveal that the grooves built on the surface of catalyst layer serve to accumulate the water nearby while oxygen tends to transfer through relatively convex region,which results from capillary pressure difference caused by the pore structure difference between the two regions.The separation of oxidant gas and generated water avoids mass confliction thus boosts mass transport efficiency.
基金Sponsored by the Fundamental Research Funds for the Central Universities(Grant No.DL12BB16)the National Natural Science Foundation of China(Grant No.51305181)
文摘Simulation models for accident section on freeway are built in microscopic traffic flow simulation environment. In these models involving 2-lane,3-lane and 4-lane freeway,one detector is set every 10 m to measure section running speed. According to the simulation results,speed spatial distribution curves for traffic accident section on freeway are drawn which help to determine dangerous sections on upstream of accident section. Furthermore,the speed spatial distribution models are obtained for every speed distribution curve. The results provide theoretical basis for determination on temporal and spatial influence ranges of traffic accident and offer reference to formulation of speed limit scheme and other management measures.
基金the National Natural Science Foundation of China(51767014),2018–2021.
文摘In order to improve the condition monitoring and fault diagnosis of wind turbines,a stacked noise reduction autoencoding network based on group normalization is proposed in this paper.The network is based on SCADA data of wind turbine operation,firstly,the group normalization(GN)algorithm is added to solve the problems of stack noise reduction autoencoding network training and slow convergence speed,and the RMSProp algorithm is used to update the weight and the bias of the autoenccoder,which further optimizes the problem that the loss function swings too much during the update process.Finally,in the last layer of the network,the softmax activation function is used to classify the results,and the output of the network is transformed into a probability distribution.The selected wind turbine SCADA data was substituted into the pre-improved and improved stacked denoising autoencoding(SDA)networks for comparative training and verification.The results show that the stacked denoising autoencoding network based on group normalization is more accurate and effective for wind turbine condition monitoring and fault diagnosis,and also provides a reference for wind turbine fault identification.
基金supported by the Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine(ZYYCXTD-D-202001)the National Natural Science Foundation of China(82104835).
文摘Gut microbiota and circulating metabolite dysbiosis predate important pathological changes in glucose metabolic disorders;however,comprehensive studies on impaired glucose tolerance(IGT),a diabetes mellitus(DM)precursor,are lacking.Here,we perform metagenomic sequencing and metabolomics on 47 pairs of individuals with IGT and newly diagnosed DM and 46 controls with normal glucose tolerance(NGT);patients with IGT are followed up after 4 years for progression to DM.Analysis of baseline data reveals significant differences in gut microbiota and serum metabolites among the IGT,DM,and NGT groups.In addition,13 types of gut microbiota and 17 types of circulating metabolites showed significant differences at baseline before IGT progressed to DM,including higher levels of Eggerthella unclassified,Coprobacillus unclassified,Clostridium ramosum,L-valine,L-norleucine,and L-isoleucine,and lower levels of Eubacterium eligens,Bacteroides faecis,Lachnospiraceae bacterium 3_1_46FAA,Alistipes senegalensis,Megaspaera elsdenii,Clostridium perfringens,α-linolenic acid,10E,12Z-octadecadienoic acid,and dodecanoic acid.A random forest model based on differential intestinal microbiota and circulating metabolites can predict the progression from IGT to DM(AUC=0.87).These results suggest that microbiome and metabolome dysbiosis occur in individuals with IGT and have important predictive values and potential for intervention in preventing IGT from progressing to DM.
基金supported by the National Natural Science Foundation of China (Grants No.81430097,81973837,82004242,82274343 and 31771481)the Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine (Grant No.ZYYCXTD-D-202001).
文摘Background:Accumulating evidence suggests that metabolic disorders,including type 2 diabetes mellitus(T2DM),can be treated with traditional Chinese medicine formulas,such as the Gegen Qinlian decoction(GQD).This study elucidates the mechanisms by which gut microbes mediate the anti-diabetic effects of GQD.Methods:We conducted a double-blind randomized clinical trial involving 120 untreated participants with T2DM.During the 12-week intervention,anthropometric measurements and diabetic traits were recorded every 4 weeks.Fecal microbiota and serum metabolites were measured before and after the intervention using 16S rDNA sequencing,liquid chromatography-mass spectrometry,and Bio-Plex panels.Results:Anti-diabetic effects were observed in the GQD group in the human trial.Specifically,glycated hemoglobin,fasting plasma glucose,and two-hour postprandial blood glucose levels were significantly lower in the GQD group than in the placebo group.Additionally,Faecalibacterium was significantly enriched in the GQD group,and the short-chain fatty acid levels were higher and the serum inflammation-associated marker levels were lower in the GQD group compared to the placebo group.Moreover,Faecalibacterium abundance negatively correlated with the levels of serum hemoglobin,fasting plasma glucose,and pro-inflammatory cytokines.Finally,the diabetes-alleviating effect of Faecalibacterium was confirmed by oral administration of Faecalibacterium prausnitzi(DSMZ 17677)in T2DMmousemodel.Conclusions:GQD improved type 2 diabetes primarily by modulating the abundance of Faecalibacterium in the gut microbiota,alleviating metabolic disorders and the inflammatory state.
基金supported by the National Natural Science Foundation of China(Grant No.22378304)the Key Funding of State Key Laboratory of Chemical Engineering(Project No.SKL-ChE-23Z02)。
文摘The use of fossil fuels results in significant carbon dioxide emissions.Biofuels have been increasingly adopted as sustainable alternatives to fossil fuel to address this environmental issue.Integrating petroleum refineries into biofuel supply chains is an effective approach to mitigating greenhouse gas emissions and improving environmental sustainability.In this study,an integrated supply chain optimization framework was established,considering the carbon trade policy.In addition,a mixed-integer nonlinear programming model was developed to optimize the selection of biomass suppliers,construction of pretreatment plants and biorefineries,integration of petroleum refineries,and selection of transportation routes with the objective of minimizing the total annual cost.An example is presented to illustrate the applicability of the model.The optimization results show that integrating petroleum refineries into biofuel supply chains effectively mitigates carbon emissions.Carbon trade policies can have a direct impact on the total annual cost and carbon emissions of the supply chain.
基金Fund of Jiangxi Province Key Laboratory of Synthetic Chemistry(No.JXSC202007)the Foundation of Jiangxi Educational Committee(No.GJJ200734)+4 种基金the Doctoral Scientific Research Start-up Foundation of East China University of Technology(No.DHBK2018044)the National Natural Science Foundation of China(Nos.21966002 and 21871047)the Training Program for Academic and Technical Leaders of Major Disciplines in Jiangxi Province(No.20194BCJ22010)the Fuzhou Youth Leading Talent Project(No.2020ED64)the Provincial College Students Innovation and Entrepreneurship Training Program(No.S202110405026).
文摘Separation of propane from natural gas is of great importance to industry.However,in light of size-based separation,there still lacks effective method to directly separate propane from natural gas,due to the comparable physical properties for these light alkanes(C1–C4)and the middle size of propane.In this work,we found that a new Th-metal-organic framework(MOF)could be an ideal solution for this issue.The Th-MOF takes UiO-66-type structure,but with the pocket sealed by six-fold imide groups;this not only precisely reduces the size of pocket to exactly match propane,but also enhances the host–guest interactions through multiple(C)H(^(δ+))∙∙∙(^(δ−))O(C)interactions.As a result,highly selective adsorption of propane over methane,ethane,and butane was observed,implying unique middle-size separation.The actual separation was confirmed by breakthrough experiments of simulated natural gas,confirming its superior application in direct separation of propane from natural gas.The separation mechanism,as unveiled by both theoretical calculation and comparative experiments,is due to the six-fold imide-sealed pocket that could effectively distinguish propane from other light alkanes through both size effect and host–guest interactions.