Doubled haploid(DH)technology is an important tool in crop breeding because it can significantly accelerate the breeding process.ZmPLA1/MATL/NLD and ZmDMP are two key genes controlling haploid induction(HI)in maize,ex...Doubled haploid(DH)technology is an important tool in crop breeding because it can significantly accelerate the breeding process.ZmPLA1/MATL/NLD and ZmDMP are two key genes controlling haploid induction(HI)in maize,exhibiting a synergistic effect.However,it is unknown whether knock out of ZmDMP orthologs can stimulate HI in rice.In this study,a ZmPLA1 ortholog(OsPLA1)and two ZmDMP orthologs(OsDMP3 and OsDMP6)were identified in rice.All three genes encode plasma membrane-localized proteins and were highly expressed in mature anthers.Knockout of OsPLA1 in both Minghui 63 and Nipponbare resulted in reduced seed setting rate(SSR)and caused HI.The osdmp3,osdmp6 and the double mutant failed to trigger HI independently,nor increased the haploid induction rate(HIR)when combined with ospla1.Repeated pollinations operations of QX654A with the ospla1 mutant significantly improve SSR,while reducing HIR.RNA-seq profiling of mature ospla1 mutant anthers indicated that a large number of differentially expressed genes(DEGs)were enriched in redox homeostasis and lipid metabolic GO terms,plant hormone signal transduction,and MAPK signaling pathways.These findings provide important insights towards construction of an efficient DH breeding technology and study of the molecular mechanism of HI in rice.展开更多
Session-based Recommendation(SBR)aims to accurately recom-mend a list of items to users based on anonymous historical session sequences.Existing methods for SBR suffer from several limitations:SBR based on Graph Neura...Session-based Recommendation(SBR)aims to accurately recom-mend a list of items to users based on anonymous historical session sequences.Existing methods for SBR suffer from several limitations:SBR based on Graph Neural Network often has information loss when constructing session graphs;Inadequate consideration is given to influencing factors,such as item price,and users’dynamic interest evolution is not taken into account.A new session recommendation model called Price-aware Session-based Recommendation(PASBR)is proposed to address these limitations.PASBR constructs session graphs by information lossless approaches to fully encode the original session information,then introduces item price as a new factor and models users’price tolerance for various items to influence users’preferences.In addition,PASBR proposes a new method to encode user intent at the item category level and tries to capture the dynamic interest of users over time.Finally,PASBR fuses the multi-perspective features to generate the global representation of users and make a prediction.Specifically,the intent,the short-term and long-term interests,and the dynamic interests of a user are combined.Experiments on two real-world datasets show that PASBR can outperform representative baselines for SBR.展开更多
This paper intends to give a code about atmospheric propagation effects affecting terahertz (THz) communication system. The main focus is on attenuation caused by atmospheric gases with the radiation transmission theo...This paper intends to give a code about atmospheric propagation effects affecting terahertz (THz) communication system. The main focus is on attenuation caused by atmospheric gases with the radiation transmission theory and the empirical continuum absorption based on the HITRAN database. Theoretical aspects about them are presented, emphasizing on those which deserve special attention as frequency increases. Laboratory measurements of the absorption spectra of laboratory air and major atmospheric gases mixed with water vapor in the 250 - 350 GHz frequency range at atmospheric pressure and room temperature on a basis of backward wave oscillators (BWOs) are obtained. The results of experiments are compared with the calculations. It is found that the water vapor transmittance is greater than the calculation. Data of these measurements agree with the results of analysis of atmospheric spectra with in statistical accuracy of experiments. Accurate measurements are also needed for further studies of the physics of the molecules and their interactions. The investigation makes it significant for enhancing accuracy of models of radiation propagation in the atmosphere.展开更多
The biggest challenge is to develop a low cost and readily available catalyst to replace expensive commercial Pt/C for efficient electrochemical oxygen reduction reaction(ORR).In this research,closo-[B_(12)H_(12)]^(2−...The biggest challenge is to develop a low cost and readily available catalyst to replace expensive commercial Pt/C for efficient electrochemical oxygen reduction reaction(ORR).In this research,closo-[B_(12)H_(12)]^(2−)and 1,10-phenanthroline-iron complexes were introduced into the porous metal-organic framework by impregnation method,and further annealing treatment achieved the successful anchoring of single-atom-Fe in B-doped CN Matrix(FeN4CB).The ORR activity of FeN4CB is comparable to the widely used commercial 20 wt%Pt/C.Where the half-wave potential(E_(1/2))in alkaline medium up to 0.84 V,and even in the face of challenging ORR in acidic medium,the E_(1/2)of ORR driven by FeN4CB is still as high as 0.81 V.When FeN4CB was used as air cathode,the open circuit voltage of Zn-air battery reaches 1.435 V,and the power density and specific capacity are as high as 177 mW cm^(−2)and 800 mAh g_(Zn)^(−1)(theoretical value:820 mAh g_(Zn)^(−1)),respectively.The dazzling point of FeN4CB also appears in the high ORR stability,whether in alkaline or acidic media,E_(1/2)and limiting current density are still close to the initial value after 5000 times cycles.After continuously running the charge-discharge test for 220 h,the charge voltage and discharge voltage of the rechargeable zinc-air battery with FeN4CB as the air cathode maintained the initial state.Density functional theory calculations reveals that introducing B atom to Fe–N4–C can adjust the electronic structure to easily break O=O bond and significantly reduce the energy barrier of the rate-determining step resulting in an improved ORR activity.展开更多
Zearalenone(ZEN)is a widely distributed mycotoxin that frequently contaminates crops and animal feed.ZEN can cause serious health problems in livestock and humans alike,leading to great economic losses in the food ind...Zearalenone(ZEN)is a widely distributed mycotoxin that frequently contaminates crops and animal feed.ZEN can cause serious health problems in livestock and humans alike,leading to great economic losses in the food industry and livestock farming.Therefore,approaches for efficient ZEN decontamination in food and feed are urgently needed.Traditional physical and chemical methods may decrease the nutritional quality of food and palatability of feed,or leading to residues and safety concerns.By contrast,biological methods for the removal or degradation of ZEN overcome these problems,especially for biological degradation by microorganisms and specific enzymes extracted from strains that can convert ZEN to less toxic or even completely harmless products.In this review,we comprehensively describe methods for ZEN degradation,focusing especially on biological strategies.Finally,emerging strategies and advice on remaining challenges in biodegradation research are also briefly discussed.展开更多
Background:Herbs are an important part of the forest ecosystem,and their diversity and biomass can reflect the restoration of vegetation after forest thinning disturbances.Based on the near-mature secondary coniferous...Background:Herbs are an important part of the forest ecosystem,and their diversity and biomass can reflect the restoration of vegetation after forest thinning disturbances.Based on the near-mature secondary coniferous and broad-leaved mixed forest in Jilin Province Forestry Experimental Zone,this study analyzed seasonal changes of species diversity and biomass of the understory herb layer after different intensities of thinning.Results:The results showed that although the composition of herbaceous species and the ranking of importance values were affected by thinning intensity,they were mainly determined by seasonal changes.Across the entire growing season,the species with the highest importance values in thinning treatments included Carex pilosa,Aegopodium alpestre,Meehania urticifolia,and Filipendula palmata,which dominated the herb layer of the coniferous and broad-leaved mixed forest.The number of species,Margalef index,Shannon-Wiener index and Simpson index all had their highest values in May,and gradually decreased with months.Pielou index was roughly inverted“N”throughout the growing season.Thinning did not increase the species diversity.Thinning can promote the total biomass,above-and below-ground biomass.The number of plants per unit area and coverage were related to the total biomass,above-and below-ground biomass.The average height had a significantly positive correlation with herb biomass in May but not in July.However,it exerted a significantly negative correlation with herb biomass in September.The biomass in the same month increased with increasing thinning intensity.Total herb biomass,above-and below-ground biomass showed positive correlations with Shannon-Winner index,Simpson index and Pielou evenness index in May.Conclusions:Thinning mainly changed the light environment in the forest,which would improve the plant diversity and biomass of herb layer in a short time.And different thinning intensity had different effects on the diversity of understory herb layer.The findings provide theoretical basis and reference for reasonable thinning and tending in coniferous and broad-leaved mixed forests.展开更多
This article continues to study the research suggestions in depth made by M.Z.Nashed and G.F.Votruba in the journal"Bull.Amer.Math.Soc."in 1974.Concerned with the pricing of non-reachable"contingent cla...This article continues to study the research suggestions in depth made by M.Z.Nashed and G.F.Votruba in the journal"Bull.Amer.Math.Soc."in 1974.Concerned with the pricing of non-reachable"contingent claims"in an incomplete financial market,when constructing a specific bounded linear operator A:l_(1)^(n)→l_(2) from a non-reflexive Banach space l_(1)^(n) to a Hilbert space l_(2),the problem of non-reachable"contingent claims"pricing is reduced to researching the(single-valued)selection of the(set-valued)metric generalized inverse A■ of the operator A.In this paper,by using the Banach space structure theory and the generalized inverse method of operators,we obtain a bounded linear single-valued selection A^(σ)=A+of A■.展开更多
Zhuzhou was one of the most polluted cities in China with the serious acid rain.Due to the implementation of air pollution control measures from 2016 to 2018,the acid rain pollution in this city has reduced.In order t...Zhuzhou was one of the most polluted cities in China with the serious acid rain.Due to the implementation of air pollution control measures from 2016 to 2018,the acid rain pollution in this city has reduced.In order to understand the recent situation,a comprehensive study on the acid rain was carried out from January 2011 to December 2020.The pH values during the study period varied from 3.3 to 7.5,with a volume-weighted mean value of 4.7.The predominant acidic components of the precipitation were SO_(4)^(2-)and NO_(3)^(-),accounting for 89.3% of the total anions.The ratio of non-sea-salt SO_(4)^(2-)to NO_(3)^(-)showed a decreasing trend,revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound type.The correlation analysis(p<0.05)showed that SO_(4)^(2-)was positively correlated with NH_(4)^(+),Ca^(2+),and Mg^(2+);hence,it predominated in precipitation as(NH_(4))_(2)SO_(4),NH_(4)HSO_(4),CaSO_(4),and MgSO_(4).Significant positive correlation of Ca^(2+)with Mg^(2+)shows that they may originated mainly from crust.Significant positive correlation between SO_(4)^(2-)and F^(-)and Cl^(-)indicate that their source may be related to the non-ferrous metal smelting industry in Zhuzhou.Further correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO_(4)^(2-)and F^(-)in precipitation,while Cl^(-)may still be emitted from other anthropogenic sources.展开更多
Bone marrow-derived mesenchymal stem cell(MSC)is one of the most actively studied cell types due to its regenerative potential and immunomodulatory properties.Conventional cell expansion methods using 2D tissue cultur...Bone marrow-derived mesenchymal stem cell(MSC)is one of the most actively studied cell types due to its regenerative potential and immunomodulatory properties.Conventional cell expansion methods using 2D tissue culture plates and 2.5D microcarriers in bioreactors can generate large cell numbers,but they compromise stem cell potency and lack mechanical preconditioning to prepare MSC for physiological loading expected in vivo.To overcome these challenges,in this work,we describe a 3D dynamic hydrogel using magneto-stimulation for direct MSC manufacturing to therapy.With our technology,we found that dynamic mechanical stimulation(DMS)enhanced matrix-integrinβ1 interactions which induced MSCs spreading and proliferation.In addition,DMS could modulate MSC biofunctions including directing MSC differentiation into specific lineages and boosting paracrine activities(e.g.,growth factor secretion)through YAP nuclear localization and FAK-ERK pathway.With our magnetic hydrogel,complex procedures from MSC manufacturing to final clinical use,can be integrated into one single platform,and we believe this‘all-in-one’technology could offer a paradigm shift to existing standards in MSC therapy.展开更多
The multifunctional films was prepared by blending chitosan and nano-ZnO with purple tomato anthocyanins or black wolfberry anthocyanins.The properties of films functioned by anthocyanins source and nano-ZnO content w...The multifunctional films was prepared by blending chitosan and nano-ZnO with purple tomato anthocyanins or black wolfberry anthocyanins.The properties of films functioned by anthocyanins source and nano-ZnO content were studied.It was found purple tomato anthocyanins showed more significant color change against pH than black wolfberry anthocyanins.The nano-ZnO were widely dispersed in matrix and enhanced the compatibility of anthocyanins with chitosan.However,the anthocyanins source influenced the properties of the films more slightly than nano-ZnO addition.The tensile strength,antioxidant and antibacterial effects of the chitosan films dramatically increased after cooperated by nano-ZnO and anthocyanins,which also enhanced with increase of nano-ZnO content,whereas the elongation at break of the composite films decreased.Especially,the anthocyanin and nano-ZnO promoted the antibacterial activity of films synergistically.Composite films made from black wolfberry anthocyanins exhibited higher mechanical performance than those made from purple tomato anthocyanins but weaker antibacterial effects.The purple tomato anthocyanins/chitosan and nano-ZnO/purple tomato anthocyanins/chitosan films effectively reflected pork spoilage,changing their colors from dark green to brown,indicating the potential for applications in active and intelligent food packaging.展开更多
Motor imagery(MI)based Brain-computer interfaces(BCIs)have a wide range of applications in the stroke rehabilitation field.However,due to the low signal-to-noise ratio and high cross-subject variation of the electroen...Motor imagery(MI)based Brain-computer interfaces(BCIs)have a wide range of applications in the stroke rehabilitation field.However,due to the low signal-to-noise ratio and high cross-subject variation of the electroencephalogram(EEG)signals generated by motor imagery,the classification performance of the existing methods still needs to be improved to meet the need of real practice.To overcome this problem,we propose a multi-scale spatial-temporal convolutional neural network called MSCNet.We introduce the contrastive learning into a multi-temporal convolution scale backbone to further improve the robustness and discrimination of embedding vectors.Experimental results of binary classification show that MSCNet outperforms the state-of-theart methods,achieving accuracy improvement of 6.04%,3.98%,and 8.15%on BCIC IV 2a,SMR-BCI,and OpenBMI datasets in subject-dependent manner,respectively.The results show that the contrastive learning method can significantly improve the classification accuracy of motor imagery EEG signals,which provides an important reference for the design of motor imagery classification algorithms.展开更多
The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing in...The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to sperm.Although a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment criteria.In this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is presented.Bioinspired by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and fabricated.This study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm samples.Results indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis group.Sperm thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation channel.Furthermore,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to blastocyst.This microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia.展开更多
Doubled haploid(DH) technology is used to obtain homozygous lines in a single generation, a technique that significantly accelerates the crop breeding trajectory. Traditionally, in vitro culture is used to generate DH...Doubled haploid(DH) technology is used to obtain homozygous lines in a single generation, a technique that significantly accelerates the crop breeding trajectory. Traditionally, in vitro culture is used to generate DHs, but this technique is limited by species and genotype recalcitrance. In vivo haploid induction(HI) through seed is widely and efficiently used in maize and was recently extended to several other crops. Here we show that in vivo HI can be triggered by mutation of DMP maternal haploid inducer genes in allopolyploid(allotetraploid) Brassica napus and Nicotiana tabacum. We developed a pipeline for selection of DMP orthologs for clustered regularly interspaced palindromic repeats mutagenesis and demonstrated average amphihaploid induction rates of2.4% and 1.2% in multiple B. napus and N. tabacum genotypes, respectively. These results further confirmed the HI ability of DMP gene in polyploid dicot crops. The DMP-HI system offers a novel DH technology to facilitate breeding in these crops. The success of this approach and the conservation of DMP genes in dicots suggest the broad applicability of this technique in other dicot crops.展开更多
Background:Cisplatin-based chemotherapy with concurrent radiotherapy is a standard treatment for advanced esophageal squamous cell carcinoma(ESCC).NS1-binding protein(NS1-BP),a member of the BTB-kelch protein fam-ily,...Background:Cisplatin-based chemotherapy with concurrent radiotherapy is a standard treatment for advanced esophageal squamous cell carcinoma(ESCC).NS1-binding protein(NS1-BP),a member of the BTB-kelch protein fam-ily,has been shown to inhibit the proliferation of Hela cells by suppressing c-Myc.In the present study,we examined the potential function role of NS1-BP expression in ESCC,and particularly,the sensitivity of ESCC to radiotherapy.Methods:NS1-BP expression was examined using immunohistochemistry in two cohorts(n=98 for the training cohort;n=46 for independent validation cohort)of ESCC patients receiving cisplatin-based chemotherapy and con-current radiotherapy.Normal esophageal mucosal tissue blocks were used as a control.We also conducted a series of in vitro and in vivo experiments to examine the potential effects of over-expressing NS1-BP on ESCC cells,and particu-larly their sensitivity to ionizing irradiation.Results:In the training cohort,NS1-BP downregulation was observed in 59%(85/144)of the ESCC specimens.NS1-BP downregulation was associated with chemoradiotherapeutic resistance and shorter disease-specific survival(DSS)in both the training and validation cohorts.Over-expressing NS1-BP in cultured ESCC cells substantially increased the cellular response to irradiation both in vitro and in vivo.NS1-BP also significantly enhanced IR-induced apoptosis,and abrogated IR-induced G2/M cell-cycle arrest and ATM/Chk1 phosphorylation.Immunoprecipitation assays indicated that NS1-BP could interact with c-Myc promoter regions to inhibit its transcription.In ESCC tissues,c-Myc expression was inversely correlated with NS1-BP levels,and was associated with a shorter DSS.Conclusions:Our findings highlight the role and importance of NS1-BP in radiosensitivity of ESCC.Targeting the NS1-BP/c-Myc pathway may provide a novel therapeutic strategy for ESCC.展开更多
基金This work was supported by the National Key Research and Development Program of China(2022YFD1200800)the China Agriculture Research System(CARS-02-05)+1 种基金Beijing Nova Program(2023067)Yunnan Province Science and Technology Department(202305AF150026).
文摘Doubled haploid(DH)technology is an important tool in crop breeding because it can significantly accelerate the breeding process.ZmPLA1/MATL/NLD and ZmDMP are two key genes controlling haploid induction(HI)in maize,exhibiting a synergistic effect.However,it is unknown whether knock out of ZmDMP orthologs can stimulate HI in rice.In this study,a ZmPLA1 ortholog(OsPLA1)and two ZmDMP orthologs(OsDMP3 and OsDMP6)were identified in rice.All three genes encode plasma membrane-localized proteins and were highly expressed in mature anthers.Knockout of OsPLA1 in both Minghui 63 and Nipponbare resulted in reduced seed setting rate(SSR)and caused HI.The osdmp3,osdmp6 and the double mutant failed to trigger HI independently,nor increased the haploid induction rate(HIR)when combined with ospla1.Repeated pollinations operations of QX654A with the ospla1 mutant significantly improve SSR,while reducing HIR.RNA-seq profiling of mature ospla1 mutant anthers indicated that a large number of differentially expressed genes(DEGs)were enriched in redox homeostasis and lipid metabolic GO terms,plant hormone signal transduction,and MAPK signaling pathways.These findings provide important insights towards construction of an efficient DH breeding technology and study of the molecular mechanism of HI in rice.
文摘Session-based Recommendation(SBR)aims to accurately recom-mend a list of items to users based on anonymous historical session sequences.Existing methods for SBR suffer from several limitations:SBR based on Graph Neural Network often has information loss when constructing session graphs;Inadequate consideration is given to influencing factors,such as item price,and users’dynamic interest evolution is not taken into account.A new session recommendation model called Price-aware Session-based Recommendation(PASBR)is proposed to address these limitations.PASBR constructs session graphs by information lossless approaches to fully encode the original session information,then introduces item price as a new factor and models users’price tolerance for various items to influence users’preferences.In addition,PASBR proposes a new method to encode user intent at the item category level and tries to capture the dynamic interest of users over time.Finally,PASBR fuses the multi-perspective features to generate the global representation of users and make a prediction.Specifically,the intent,the short-term and long-term interests,and the dynamic interests of a user are combined.Experiments on two real-world datasets show that PASBR can outperform representative baselines for SBR.
文摘This paper intends to give a code about atmospheric propagation effects affecting terahertz (THz) communication system. The main focus is on attenuation caused by atmospheric gases with the radiation transmission theory and the empirical continuum absorption based on the HITRAN database. Theoretical aspects about them are presented, emphasizing on those which deserve special attention as frequency increases. Laboratory measurements of the absorption spectra of laboratory air and major atmospheric gases mixed with water vapor in the 250 - 350 GHz frequency range at atmospheric pressure and room temperature on a basis of backward wave oscillators (BWOs) are obtained. The results of experiments are compared with the calculations. It is found that the water vapor transmittance is greater than the calculation. Data of these measurements agree with the results of analysis of atmospheric spectra with in statistical accuracy of experiments. Accurate measurements are also needed for further studies of the physics of the molecules and their interactions. The investigation makes it significant for enhancing accuracy of models of radiation propagation in the atmosphere.
基金financially supported by the NSFC-Yunnan Joint Foundation(U2002213)the Double Tops Joint Fund of the Yunnan Science and Technology Bureau and Yunnan University(2019FY003025)the‘Double-First Class’University Construction Project(C176220100042 and CZ21623201)。
文摘The biggest challenge is to develop a low cost and readily available catalyst to replace expensive commercial Pt/C for efficient electrochemical oxygen reduction reaction(ORR).In this research,closo-[B_(12)H_(12)]^(2−)and 1,10-phenanthroline-iron complexes were introduced into the porous metal-organic framework by impregnation method,and further annealing treatment achieved the successful anchoring of single-atom-Fe in B-doped CN Matrix(FeN4CB).The ORR activity of FeN4CB is comparable to the widely used commercial 20 wt%Pt/C.Where the half-wave potential(E_(1/2))in alkaline medium up to 0.84 V,and even in the face of challenging ORR in acidic medium,the E_(1/2)of ORR driven by FeN4CB is still as high as 0.81 V.When FeN4CB was used as air cathode,the open circuit voltage of Zn-air battery reaches 1.435 V,and the power density and specific capacity are as high as 177 mW cm^(−2)and 800 mAh g_(Zn)^(−1)(theoretical value:820 mAh g_(Zn)^(−1)),respectively.The dazzling point of FeN4CB also appears in the high ORR stability,whether in alkaline or acidic media,E_(1/2)and limiting current density are still close to the initial value after 5000 times cycles.After continuously running the charge-discharge test for 220 h,the charge voltage and discharge voltage of the rechargeable zinc-air battery with FeN4CB as the air cathode maintained the initial state.Density functional theory calculations reveals that introducing B atom to Fe–N4–C can adjust the electronic structure to easily break O=O bond and significantly reduce the energy barrier of the rate-determining step resulting in an improved ORR activity.
基金We acknowledge the financial support from National Key Research and Development Program of China(No.2018YFC1604100).
文摘Zearalenone(ZEN)is a widely distributed mycotoxin that frequently contaminates crops and animal feed.ZEN can cause serious health problems in livestock and humans alike,leading to great economic losses in the food industry and livestock farming.Therefore,approaches for efficient ZEN decontamination in food and feed are urgently needed.Traditional physical and chemical methods may decrease the nutritional quality of food and palatability of feed,or leading to residues and safety concerns.By contrast,biological methods for the removal or degradation of ZEN overcome these problems,especially for biological degradation by microorganisms and specific enzymes extracted from strains that can convert ZEN to less toxic or even completely harmless products.In this review,we comprehensively describe methods for ZEN degradation,focusing especially on biological strategies.Finally,emerging strategies and advice on remaining challenges in biodegradation research are also briefly discussed.
基金financially supported by a grant from the National Key Research and Development Program of China(2017YFC0504102)the Science and Technology Program of Jilin Provincial Education Department(JJKH20180349KJ).
文摘Background:Herbs are an important part of the forest ecosystem,and their diversity and biomass can reflect the restoration of vegetation after forest thinning disturbances.Based on the near-mature secondary coniferous and broad-leaved mixed forest in Jilin Province Forestry Experimental Zone,this study analyzed seasonal changes of species diversity and biomass of the understory herb layer after different intensities of thinning.Results:The results showed that although the composition of herbaceous species and the ranking of importance values were affected by thinning intensity,they were mainly determined by seasonal changes.Across the entire growing season,the species with the highest importance values in thinning treatments included Carex pilosa,Aegopodium alpestre,Meehania urticifolia,and Filipendula palmata,which dominated the herb layer of the coniferous and broad-leaved mixed forest.The number of species,Margalef index,Shannon-Wiener index and Simpson index all had their highest values in May,and gradually decreased with months.Pielou index was roughly inverted“N”throughout the growing season.Thinning did not increase the species diversity.Thinning can promote the total biomass,above-and below-ground biomass.The number of plants per unit area and coverage were related to the total biomass,above-and below-ground biomass.The average height had a significantly positive correlation with herb biomass in May but not in July.However,it exerted a significantly negative correlation with herb biomass in September.The biomass in the same month increased with increasing thinning intensity.Total herb biomass,above-and below-ground biomass showed positive correlations with Shannon-Winner index,Simpson index and Pielou evenness index in May.Conclusions:Thinning mainly changed the light environment in the forest,which would improve the plant diversity and biomass of herb layer in a short time.And different thinning intensity had different effects on the diversity of understory herb layer.The findings provide theoretical basis and reference for reasonable thinning and tending in coniferous and broad-leaved mixed forests.
基金supported by the National Science Foundation (12001142)Harbin Normal University doctoral initiation Fund (XKB201812)supported by the Science Foundation Grant of Heilongjiang Province (LH2019A017)
文摘This article continues to study the research suggestions in depth made by M.Z.Nashed and G.F.Votruba in the journal"Bull.Amer.Math.Soc."in 1974.Concerned with the pricing of non-reachable"contingent claims"in an incomplete financial market,when constructing a specific bounded linear operator A:l_(1)^(n)→l_(2) from a non-reflexive Banach space l_(1)^(n) to a Hilbert space l_(2),the problem of non-reachable"contingent claims"pricing is reduced to researching the(single-valued)selection of the(set-valued)metric generalized inverse A■ of the operator A.In this paper,by using the Banach space structure theory and the generalized inverse method of operators,we obtain a bounded linear single-valued selection A^(σ)=A+of A■.
基金supported by the National Natural Science Foundation of China(Nos.41205093,42075182)the National Department Public Benefit Research Foundation(No.201109005)。
文摘Zhuzhou was one of the most polluted cities in China with the serious acid rain.Due to the implementation of air pollution control measures from 2016 to 2018,the acid rain pollution in this city has reduced.In order to understand the recent situation,a comprehensive study on the acid rain was carried out from January 2011 to December 2020.The pH values during the study period varied from 3.3 to 7.5,with a volume-weighted mean value of 4.7.The predominant acidic components of the precipitation were SO_(4)^(2-)and NO_(3)^(-),accounting for 89.3% of the total anions.The ratio of non-sea-salt SO_(4)^(2-)to NO_(3)^(-)showed a decreasing trend,revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound type.The correlation analysis(p<0.05)showed that SO_(4)^(2-)was positively correlated with NH_(4)^(+),Ca^(2+),and Mg^(2+);hence,it predominated in precipitation as(NH_(4))_(2)SO_(4),NH_(4)HSO_(4),CaSO_(4),and MgSO_(4).Significant positive correlation of Ca^(2+)with Mg^(2+)shows that they may originated mainly from crust.Significant positive correlation between SO_(4)^(2-)and F^(-)and Cl^(-)indicate that their source may be related to the non-ferrous metal smelting industry in Zhuzhou.Further correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO_(4)^(2-)and F^(-)in precipitation,while Cl^(-)may still be emitted from other anthropogenic sources.
基金supported by NUS Presidential Young Professorship,MOE Tier 1 grantsupported by the NUS Research Scholarship.
文摘Bone marrow-derived mesenchymal stem cell(MSC)is one of the most actively studied cell types due to its regenerative potential and immunomodulatory properties.Conventional cell expansion methods using 2D tissue culture plates and 2.5D microcarriers in bioreactors can generate large cell numbers,but they compromise stem cell potency and lack mechanical preconditioning to prepare MSC for physiological loading expected in vivo.To overcome these challenges,in this work,we describe a 3D dynamic hydrogel using magneto-stimulation for direct MSC manufacturing to therapy.With our technology,we found that dynamic mechanical stimulation(DMS)enhanced matrix-integrinβ1 interactions which induced MSCs spreading and proliferation.In addition,DMS could modulate MSC biofunctions including directing MSC differentiation into specific lineages and boosting paracrine activities(e.g.,growth factor secretion)through YAP nuclear localization and FAK-ERK pathway.With our magnetic hydrogel,complex procedures from MSC manufacturing to final clinical use,can be integrated into one single platform,and we believe this‘all-in-one’technology could offer a paradigm shift to existing standards in MSC therapy.
基金This research received funding from the Research and Innovation Initiatives of WHPU(Grant No.2023Y29).
文摘The multifunctional films was prepared by blending chitosan and nano-ZnO with purple tomato anthocyanins or black wolfberry anthocyanins.The properties of films functioned by anthocyanins source and nano-ZnO content were studied.It was found purple tomato anthocyanins showed more significant color change against pH than black wolfberry anthocyanins.The nano-ZnO were widely dispersed in matrix and enhanced the compatibility of anthocyanins with chitosan.However,the anthocyanins source influenced the properties of the films more slightly than nano-ZnO addition.The tensile strength,antioxidant and antibacterial effects of the chitosan films dramatically increased after cooperated by nano-ZnO and anthocyanins,which also enhanced with increase of nano-ZnO content,whereas the elongation at break of the composite films decreased.Especially,the anthocyanin and nano-ZnO promoted the antibacterial activity of films synergistically.Composite films made from black wolfberry anthocyanins exhibited higher mechanical performance than those made from purple tomato anthocyanins but weaker antibacterial effects.The purple tomato anthocyanins/chitosan and nano-ZnO/purple tomato anthocyanins/chitosan films effectively reflected pork spoilage,changing their colors from dark green to brown,indicating the potential for applications in active and intelligent food packaging.
基金support from the National Key Research and Development Program of China(Grant No.2018YFC1312903)Beijing Natural Science Foundation(Grant No.Z200016)the Fundamental Research Funds for the Central Universities(Grant No.KG16137101,KG16187001 and KG16123001).
文摘Motor imagery(MI)based Brain-computer interfaces(BCIs)have a wide range of applications in the stroke rehabilitation field.However,due to the low signal-to-noise ratio and high cross-subject variation of the electroencephalogram(EEG)signals generated by motor imagery,the classification performance of the existing methods still needs to be improved to meet the need of real practice.To overcome this problem,we propose a multi-scale spatial-temporal convolutional neural network called MSCNet.We introduce the contrastive learning into a multi-temporal convolution scale backbone to further improve the robustness and discrimination of embedding vectors.Experimental results of binary classification show that MSCNet outperforms the state-of-theart methods,achieving accuracy improvement of 6.04%,3.98%,and 8.15%on BCIC IV 2a,SMR-BCI,and OpenBMI datasets in subject-dependent manner,respectively.The results show that the contrastive learning method can significantly improve the classification accuracy of motor imagery EEG signals,which provides an important reference for the design of motor imagery classification algorithms.
基金supported by the Key Research and Development Project of Hubei Province,China(No.2021BCA111)。
文摘The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to sperm.Although a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment criteria.In this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is presented.Bioinspired by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and fabricated.This study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm samples.Results indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis group.Sperm thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation channel.Furthermore,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to blastocyst.This microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia.
基金supported by National Key Research and Development Program of China (2016YFD0101200, 2018YFD0100201)China Agriculture Research System of MOF and MARA, National Natural Science Foundation of China (91935303, 32001554)+1 种基金the 2020 Research Program of Sanya Yazhou Bay Science and Technology City (SKJC-2020-02-003)China Postdoctoral Science Foundation (2020TQ0356)
文摘Doubled haploid(DH) technology is used to obtain homozygous lines in a single generation, a technique that significantly accelerates the crop breeding trajectory. Traditionally, in vitro culture is used to generate DHs, but this technique is limited by species and genotype recalcitrance. In vivo haploid induction(HI) through seed is widely and efficiently used in maize and was recently extended to several other crops. Here we show that in vivo HI can be triggered by mutation of DMP maternal haploid inducer genes in allopolyploid(allotetraploid) Brassica napus and Nicotiana tabacum. We developed a pipeline for selection of DMP orthologs for clustered regularly interspaced palindromic repeats mutagenesis and demonstrated average amphihaploid induction rates of2.4% and 1.2% in multiple B. napus and N. tabacum genotypes, respectively. These results further confirmed the HI ability of DMP gene in polyploid dicot crops. The DMP-HI system offers a novel DH technology to facilitate breeding in these crops. The success of this approach and the conservation of DMP genes in dicots suggest the broad applicability of this technique in other dicot crops.
基金supported by the National Nature Science Foundation of China(81401948,81472182,81372518 and 81472797).
文摘Background:Cisplatin-based chemotherapy with concurrent radiotherapy is a standard treatment for advanced esophageal squamous cell carcinoma(ESCC).NS1-binding protein(NS1-BP),a member of the BTB-kelch protein fam-ily,has been shown to inhibit the proliferation of Hela cells by suppressing c-Myc.In the present study,we examined the potential function role of NS1-BP expression in ESCC,and particularly,the sensitivity of ESCC to radiotherapy.Methods:NS1-BP expression was examined using immunohistochemistry in two cohorts(n=98 for the training cohort;n=46 for independent validation cohort)of ESCC patients receiving cisplatin-based chemotherapy and con-current radiotherapy.Normal esophageal mucosal tissue blocks were used as a control.We also conducted a series of in vitro and in vivo experiments to examine the potential effects of over-expressing NS1-BP on ESCC cells,and particu-larly their sensitivity to ionizing irradiation.Results:In the training cohort,NS1-BP downregulation was observed in 59%(85/144)of the ESCC specimens.NS1-BP downregulation was associated with chemoradiotherapeutic resistance and shorter disease-specific survival(DSS)in both the training and validation cohorts.Over-expressing NS1-BP in cultured ESCC cells substantially increased the cellular response to irradiation both in vitro and in vivo.NS1-BP also significantly enhanced IR-induced apoptosis,and abrogated IR-induced G2/M cell-cycle arrest and ATM/Chk1 phosphorylation.Immunoprecipitation assays indicated that NS1-BP could interact with c-Myc promoter regions to inhibit its transcription.In ESCC tissues,c-Myc expression was inversely correlated with NS1-BP levels,and was associated with a shorter DSS.Conclusions:Our findings highlight the role and importance of NS1-BP in radiosensitivity of ESCC.Targeting the NS1-BP/c-Myc pathway may provide a novel therapeutic strategy for ESCC.