In recent years,deep learning methods have developed rapidly and found application in many fields,including natural language processing.In the field of aspect-level sentiment analysis,deep learning methods can also gr...In recent years,deep learning methods have developed rapidly and found application in many fields,including natural language processing.In the field of aspect-level sentiment analysis,deep learning methods can also greatly improve the performance of models.However,previous studies did not take into account the relationship between user feature extraction and contextual terms.To address this issue,we use data feature extraction and deep learning combined to develop an aspect-level sentiment analysis method.To be specific,we design user comment feature extraction(UCFE)to distill salient features from users’historical comments and transform them into representative user feature vectors.Then,the aspect-sentence graph convolutional neural network(ASGCN)is used to incorporate innovative techniques for calculating adjacency matrices;meanwhile,ASGCN emphasizes capturing nuanced semantics within relationships among aspect words and syntactic dependency types.Afterward,three embedding methods are devised to embed the user feature vector into the ASGCN model.The empirical validations verify the effectiveness of these models,consistently surpassing conventional benchmarks and reaffirming the indispensable role of deep learning in advancing sentiment analysis methodologies.展开更多
Previous studies have demonstrated that doublecortin-positive immature neurons exist pre- dominantly in the superficial layer of the cerebral cortex of adult mammals such as guinea pigs, and these neurons exhibit very...Previous studies have demonstrated that doublecortin-positive immature neurons exist pre- dominantly in the superficial layer of the cerebral cortex of adult mammals such as guinea pigs, and these neurons exhibit very weak properties of self-proliferation during adulthood under physiological conditions. To verify whether environmental enrichment has an impact on the proliferation and maturation of these immature neurons in the prefrontal cortex of adult guinea pigs, healthy adult guinea pigs were subjected to short-term environmental enrichment. Animals were allowed to play with various cognitive and physical stimulating objects over a period of 2 weeks, twice per day, for 60 minutes each. Immunofluorescence staining results indicated that the number of doublecortin-positive cells in layer II of the prefrontal cortex was significantly increased after short-term environmental enrichment exposure. In addition, these doublecortin-positive cells co-expressed 5-bromo-2-deoxyuridine （a marker of cell prolifera- tion）, c-Fos （a marker of cell viability） and NeuN （a marker of mature neurons）. Experimental findings showed that short-term environmental enrichment can induce proliferation, activation and maturation of doublecortin-positive cells in layer II of the prefrontal cortex of adult guinea pigs.展开更多
A novel population of cells expressing typical markers of immature neurons, such as doublecortin-positive cells, was recently identified. This population was predominantly located in layer II of the adult cerebral cor...A novel population of cells expressing typical markers of immature neurons, such as doublecortin-positive cells, was recently identified. This population was predominantly located in layer II of the adult cerebral cortex of relatively large mammals. These cells appear to maintain an immature phenotype for a protracted time window, suggesting a lifelong role in cortical plasticity under normal physiological conditions, and possibly under pathological conditions as well. This review discusses recent evidence regarding the detailed features of these unique cells, including their distribution, morphology, fate, temporal and spatial origin, as well as their relevance and possible functions in various physiological and pathological conditions. In addition, we review studies that have produced conflicting results, possibly as a result of discrepancies in the methodology used to detect neurogenesis. In theory, the properties of these cells indicate that they might exert a significant impact on neocortical function, informing potential therapeutic strategies designed to induce endogenous neurogenesis in the treatment of neuropathological diseases.展开更多
Metal halide perovskite solar cells have attracted considerable attention because of their high-power conversion efficiency and costeffective solution-processable fabrication;however,they exhibit poor structural stabi...Metal halide perovskite solar cells have attracted considerable attention because of their high-power conversion efficiency and costeffective solution-processable fabrication;however,they exhibit poor structural stability.Two-dimensional(2D)Ruddlesden-Popper(RP)perovskites could address the aforementioned issue and present excellent stability because of their hydrophobic organic spacer cations.However,the crystallographic orientation of 2D crystals should be perpendicular to the bottom substrates for charges to transport fast and be collected in solar cells.Moreover,controlling the crystallographic orientation of the 2D RP perovskites prepared by the solution process is difficult.Herein,we reviewed the progress of recent research regarding 2D RP perovskite films with the focus on the crystallographic orientation mechanism and orientation controlling methods.Furthermore,the current issues and prospects of 2D RP perovskites in the photovoltaic field were discussed to elucidate their development and application in the future.展开更多
[Objective] The paper was to improve the blast resistance of insect-resistant transgenic rice. [Method] The Japonica rice variety Jikang10, a new transgenic variety with exogenous insect-resistant gene Cry1C, was used...[Objective] The paper was to improve the blast resistance of insect-resistant transgenic rice. [Method] The Japonica rice variety Jikang10, a new transgenic variety with exogenous insect-resistant gene Cry1C, was used as the receptor, and Kongyu 131, a traditional breeding variety with broad-spectrum high blast resistance genes Pi1 and Pi2, was used as the donor to breeding new rice varieties. The genes were polymerized by hybridization and multi-generation backcrossing, and the offspring of each generation was screened by molecular marker assisted selection, field identification of multi-resistance against insect pests and diseases and agronomic trait selection. [Result] Four lines SK01, SK02, SK03 and SK04 with better resistances to insect pests and blast and outstanding agronomic traits in field were selected. [Conclusion] The results will lay foundations for breeding new multi-resistance rice varieties in Huanghuai rice region.展开更多
Metal halide perovskite light-emitting diodes(PeLEDs)show great potential in ultra-high-definition displays,due to their narrowband emission,wide color gamut(~140%),and cost-effective solution processability[1].Thanks...Metal halide perovskite light-emitting diodes(PeLEDs)show great potential in ultra-high-definition displays,due to their narrowband emission,wide color gamut(~140%),and cost-effective solution processability[1].Thanks to scientists'tremendous efforts,the external quantum efficiencies(EQEs)for the state-of-the-art PeLEDs emitting near-infrared and green light have reached 21.6%[2]and 23.4%[3],respectively.However,blue PeLEDs,as one of the essential technologies for perovskite-based high-resolution monitors and white light-ing,are still inferior to their red and green counterparts.展开更多
Moral education is the fundamental task of education.It does not only include the inheritance of the fine traditional thoughts of the Chinese nation,but also the deepening of the new era of education concept with the ...Moral education is the fundamental task of education.It does not only include the inheritance of the fine traditional thoughts of the Chinese nation,but also the deepening of the new era of education concept with the new development in this changing world.Moral education has been widely implemented in the practical education process of colleges and universities and has achieved some outstanding results,but there are still some areas to be improved.Teachers in colleges and universities are the key to implement the concept of moral education,and classroom teaching is the main channel for the implementation of moral education.Therefore,teachers in colleges and universities need to deeply understand the essence and connotation of moral education,accurately grasp the practical problems existing in moral education,focus on the curriculum construction and the main channel of the classroom,and make every effort to exercise curriculum ideology and politics.展开更多
Phosphorus(P)is involved in various biochemical reactions in plant growth,so it is beneficial to plants growing in soils contaminated by metals,including cadmium(Cd).However,few studies have reported on the mechanisti...Phosphorus(P)is involved in various biochemical reactions in plant growth,so it is beneficial to plants growing in soils contaminated by metals,including cadmium(Cd).However,few studies have reported on the mechanistic roles of P in mitigating Cd toxicity to ryegrass root,and especially in alleviating the disruption of the mitochondrial function of living cells.In this study,the physiological and biochemical mechanisms associated with ryegrass growth under various Cd and P treatments were investigated using leaching and pot systems.The concentration of Cd in soil leachates showed a significantly positive relationship with redox potential(P<0.05),but negative relationship(P<0.05)with leachate pH values and dissolved organic carbon(DOC),indicating that exogenous P addition(as H_(2)PO_(4)*)may decrease Cd leaching from contaminated soil.Compared to the control(without P addition),the cumulative Cd content was reduced by 53.3%and 64.5%in the soil leachate with exogenous P application(20 mg/L and 80 mg/L),respectively.Notably,application of P decreased the Cd concentrations in the symplastic fractions and increased the Cd concentrations in the apoplastic fractions in root tips,which may help to alleviate Cd stress to the protoplast.Moreover,exogenous P was found to play a positive role in mitochondrial function and Ca^(2+)variation in root cells under Cd stress,which provides novel insights into the mechanisms of exogenous P in alleviating plant Cd injury.展开更多
The electric catfish(Malapterurus electricus),belonging to the family Malapteruridae,order Siluriformes(Actinopterygii:Ostariophysi),is one of the six branches that has independently evolved electrical organs.We assem...The electric catfish(Malapterurus electricus),belonging to the family Malapteruridae,order Siluriformes(Actinopterygii:Ostariophysi),is one of the six branches that has independently evolved electrical organs.We assembled a 796.75 Mb M.electricus genome and anchored 88.72%sequences into 28 chromosomes.Gene family analysis revealed 295 expanded gene families that were enriched on functions related to glutamate receptors.Convergent evolutionary analyses of electric organs among different lineage of electric fishes further revealed that the coding gene of rho guanine nucleotide exchange factor 4-like(arhgef4),which is associated with G-protein coupled receptor(GPCR)signaling pathway,underwent adaptive parallel evolution.Gene identification suggests visual degradation in catfishes,and an important role for taste in environmental adaptation.Our findings fill in the genomic data for a branch of electric fish and provide a relevant genetic basis for the adaptive evolution of Siluriformes.展开更多
Drought is a major environmental stress limiting global wheat(Triticum aestivum)production.Exploring drought tolerance genes is important for improving drought adaptation in this crop.Here,we cloned and characterized ...Drought is a major environmental stress limiting global wheat(Triticum aestivum)production.Exploring drought tolerance genes is important for improving drought adaptation in this crop.Here,we cloned and characterized TaTIP41,a novel drought tolerance gene in wheat.TaTIP41 is a putative conserved component of target of rapamycin(TOR)signaling,and the Ta TIP41 homoeologs were expressed in response to drought stress and abscisic acid(ABA).The overexpression of Ta TIP41 enhanced drought tolerance and the ABA response,including ABA-induced stomatal closure,while its downregulation using RNA interference(RNAi)had the opposite effect.Furthermore,Ta TIP41 physically interacted with TaTAP46,another conserved component of TOR signaling.Like TaTIP41,TaTAP46 positively regulated drought tolerance.Furthermore,TaTIP41 and TaTAP46 interacted with type-2A protein phosphatase(PP2A)catalytic subunits,such as TaPP2A-2,and inhibited their enzymatic activities.Silencing TaPP2A-2 improved drought tolerance in wheat.Together,our findings provide new insights into the roles of TaTIP41 and TaTAP46 in the drought tolerance and ABA response in wheat,and their potential application in improving wheat environmental adaptability.展开更多
TiAl alloys are susceptible to cracks during electron beam welding because their limited ductility cannot accommodate the stress generated under fast cooling rate.In this work,pre-heating and post-heating via defocuse...TiAl alloys are susceptible to cracks during electron beam welding because their limited ductility cannot accommodate the stress generated under fast cooling rate.In this work,pre-heating and post-heating via defocused electron beam were used to obtain well-welded joints without cracks.Lower crack sensitivity of joints was attributed to the microstructure evolution to obtain more ability of stress accommodation with the increasing heating beam current and heating time.Long-time pre-heating of 5 min and post-heating of 12 min led to reduced volume fraction of residualβ0 phase with the growth ofα2/γlamellar colonies in the fusion zone(FZ).The refined microstructure of FZ contributed to the highest hardness of the FZ,and the fracture happened at the base material(BM)in tensile tests,indicating that the tensile properties of the welding seam surpassed that of the BM.This work provides an effective way to obtain TiAl joints with better mechanical properties of the welding seam than that of the BM,which is a breakthrough in the welding of TiAl alloys.展开更多
A quantitative method for clopidogrel using online-SPE tandem LC–MS/MS was developed and fully validated according to the well-established FDA guidelines.The method achieves adequate sensitivity for pharmacokinetic s...A quantitative method for clopidogrel using online-SPE tandem LC–MS/MS was developed and fully validated according to the well-established FDA guidelines.The method achieves adequate sensitivity for pharmacokinetic studies,with lower limit of quantifications(LLOQs)as low as 10 pg/m L.Chromatographic separations were performed on reversed phase columns Kromasil Eternity-2.5-C18-UHPLC for both methods.Positive electrospray ionization in multiple reaction monitoring(MRM)mode was employed for signal detection and a deuterated analogue(clopidogrel-d_4)was used as internal standard(IS).Adjustments in sample preparation,including introduction of an online-SPE system proved to be the most effective method to solve the analyte back-conversion in clinical samples.Pooled clinical samples(two levels)were prepared and successfully used as real-sample quality control(QC)in the validation of back-conversion testing under different conditions.The result showed that the real samples were stable in room temperature for 24 h.Linearity,precision,extraction recovery,matrix effect on spiked QC samples and stability tests on both spiked QCs and real sample QCs stored in different conditions met the acceptance criteria.This online-SPE method was successfully applied to a bioequivalence study of75 mg single dose clopidogrel tablets in 48 healthy male subjects.展开更多
Dissimilar high-energy beam(HEB)welding is necessary in many industrial applications.Different composition of heat-affected zone(HAZ)and weld metal(WM)lead to variation in mechanical properties within the dissimilar j...Dissimilar high-energy beam(HEB)welding is necessary in many industrial applications.Different composition of heat-affected zone(HAZ)and weld metal(WM)lead to variation in mechanical properties within the dissimilar joint,which determines the performance of the welded structure.In the present study,appropriate filler material was used during electron beam welding(EBW)to obtain a reliable dissimilar joint between reduced-activation ferritic-martensitic(RAFM)steel and 316L austenitic stainless steel.It was observed that the layered structure occurred in the weld metal with 310S filler(310S-WM),which had the inferior resistance to thermal disturbance,leading to severe hardening of 310S-WM after one-step tempering treatment.To further ameliorate the joint inhomogeneity,two-step heat treatment processes were imposed to the joints and optimized.δ-ferrite in the layered structure transformed intoγ-phase in the first-step normalizing and remained stable during cooling.In the second-step of tempering,tempered martensite was obtained in the HAZ of the RAFM steel,while the microstructure of 310S-WM was not affected.Thus,the optimized properties for HAZ and 310S-WM in dissimilar welded joint was both obtained by a two-step heat treatment.The creep failure position of two dissimilar joints both occurred in CLAM-BM.展开更多
The Patched 1(PTCH1)gene encodes a membrane receptor involved in the Hedge-hog(Hh)signaling pathway,an abnormal state of which may result in congenital defects or hu-man tumors.In this study,we conducted whole-exome s...The Patched 1(PTCH1)gene encodes a membrane receptor involved in the Hedge-hog(Hh)signaling pathway,an abnormal state of which may result in congenital defects or hu-man tumors.In this study,we conducted whole-exome sequencing on a three-generation Chinese family characterized with variable penetrance of orofacial clefts.A rare heterozygous variant in the PTCH1 gene(c.2833C>T p.R945X)was identified as a disease-associated mutation.Structural modeling revealed a truncation starting from the middle of the second extracellular domain of PTCH1 protein.This may damage its ligand recognition and sterol transportation abilities,thereby affecting the Hh signaling pathway.Biochemical assays indi-cated that the R945X protein had reduced stability compared to the wild-type in vitro.In addi-tion,we reviewed the locations and mutation types of PTCH1 variants in individuals with clefting phenotypes,and analyzed the associations between clefts and locations or types of variants within PTCH1.Our findings provide further evidence that PTCH1 variants result in or-ofacial clefts,and contributed to genetic counseling and clinical surveillance in this family.展开更多
基金This work is partly supported by the Fundamental Research Funds for the Central Universities(CUC230A013)It is partly supported by Natural Science Foundation of Beijing Municipality(No.4222038)It is also supported by National Natural Science Foundation of China(Grant No.62176240).
文摘In recent years,deep learning methods have developed rapidly and found application in many fields,including natural language processing.In the field of aspect-level sentiment analysis,deep learning methods can also greatly improve the performance of models.However,previous studies did not take into account the relationship between user feature extraction and contextual terms.To address this issue,we use data feature extraction and deep learning combined to develop an aspect-level sentiment analysis method.To be specific,we design user comment feature extraction(UCFE)to distill salient features from users’historical comments and transform them into representative user feature vectors.Then,the aspect-sentence graph convolutional neural network(ASGCN)is used to incorporate innovative techniques for calculating adjacency matrices;meanwhile,ASGCN emphasizes capturing nuanced semantics within relationships among aspect words and syntactic dependency types.Afterward,three embedding methods are devised to embed the user feature vector into the ASGCN model.The empirical validations verify the effectiveness of these models,consistently surpassing conventional benchmarks and reaffirming the indispensable role of deep learning in advancing sentiment analysis methodologies.
基金jointly supported by the National Natural Science Foundation of China[grant number 41825010]the Strategic Priority Research Program of the Chinese Academy of Sciences[grant number XDA23090102]。
基金the National Natural Science Foundation of China,No.30900773the Natural Science Foundation of Hunan Province in China,No.11JJ2020Young Teachers Training Program of University of Hunan Province
文摘Previous studies have demonstrated that doublecortin-positive immature neurons exist pre- dominantly in the superficial layer of the cerebral cortex of adult mammals such as guinea pigs, and these neurons exhibit very weak properties of self-proliferation during adulthood under physiological conditions. To verify whether environmental enrichment has an impact on the proliferation and maturation of these immature neurons in the prefrontal cortex of adult guinea pigs, healthy adult guinea pigs were subjected to short-term environmental enrichment. Animals were allowed to play with various cognitive and physical stimulating objects over a period of 2 weeks, twice per day, for 60 minutes each. Immunofluorescence staining results indicated that the number of doublecortin-positive cells in layer II of the prefrontal cortex was significantly increased after short-term environmental enrichment exposure. In addition, these doublecortin-positive cells co-expressed 5-bromo-2-deoxyuridine （a marker of cell prolifera- tion）, c-Fos （a marker of cell viability） and NeuN （a marker of mature neurons）. Experimental findings showed that short-term environmental enrichment can induce proliferation, activation and maturation of doublecortin-positive cells in layer II of the prefrontal cortex of adult guinea pigs.
基金the National Natural Science Foundation of China,No.30900773the National University Basic Research Foundation of China,No.2010QZZD022
文摘A novel population of cells expressing typical markers of immature neurons, such as doublecortin-positive cells, was recently identified. This population was predominantly located in layer II of the adult cerebral cortex of relatively large mammals. These cells appear to maintain an immature phenotype for a protracted time window, suggesting a lifelong role in cortical plasticity under normal physiological conditions, and possibly under pathological conditions as well. This review discusses recent evidence regarding the detailed features of these unique cells, including their distribution, morphology, fate, temporal and spatial origin, as well as their relevance and possible functions in various physiological and pathological conditions. In addition, we review studies that have produced conflicting results, possibly as a result of discrepancies in the methodology used to detect neurogenesis. In theory, the properties of these cells indicate that they might exert a significant impact on neocortical function, informing potential therapeutic strategies designed to induce endogenous neurogenesis in the treatment of neuropathological diseases.
基金This work was financially supported by the National Key Research and Development Program of China(No.2017YFE0119700)the National Natural Science Found-ation of China(Nos.51961135107,51774034,and 51772026).
文摘Metal halide perovskite solar cells have attracted considerable attention because of their high-power conversion efficiency and costeffective solution-processable fabrication;however,they exhibit poor structural stability.Two-dimensional(2D)Ruddlesden-Popper(RP)perovskites could address the aforementioned issue and present excellent stability because of their hydrophobic organic spacer cations.However,the crystallographic orientation of 2D crystals should be perpendicular to the bottom substrates for charges to transport fast and be collected in solar cells.Moreover,controlling the crystallographic orientation of the 2D RP perovskites prepared by the solution process is difficult.Herein,we reviewed the progress of recent research regarding 2D RP perovskite films with the focus on the crystallographic orientation mechanism and orientation controlling methods.Furthermore,the current issues and prospects of 2D RP perovskites in the photovoltaic field were discussed to elucidate their development and application in the future.
基金Supported by The Agricultural Seed Improvement Project of Shandong (2019LZGC017, 2019LZGC003)Agricultural Industry Research System (Rice) Project of Shandong Province (SDAIT-17-03)The Agricultural and Technology Innovation Project of Shandong Academy of Agricultural Sciences(CXGC2021A30)。
文摘[Objective] The paper was to improve the blast resistance of insect-resistant transgenic rice. [Method] The Japonica rice variety Jikang10, a new transgenic variety with exogenous insect-resistant gene Cry1C, was used as the receptor, and Kongyu 131, a traditional breeding variety with broad-spectrum high blast resistance genes Pi1 and Pi2, was used as the donor to breeding new rice varieties. The genes were polymerized by hybridization and multi-generation backcrossing, and the offspring of each generation was screened by molecular marker assisted selection, field identification of multi-resistance against insect pests and diseases and agronomic trait selection. [Result] Four lines SK01, SK02, SK03 and SK04 with better resistances to insect pests and blast and outstanding agronomic traits in field were selected. [Conclusion] The results will lay foundations for breeding new multi-resistance rice varieties in Huanghuai rice region.
基金J.Tian thanks the National Key Research and Development Program of China(2017YFE0119700)National Natural Science Foundation of China(51961135107,51774034,51772026)+2 种基金Beijing Natural Science Foundation(2182039)L.Ding thanks the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032 and 21961160720)for financial support.
文摘Metal halide perovskite light-emitting diodes(PeLEDs)show great potential in ultra-high-definition displays,due to their narrowband emission,wide color gamut(~140%),and cost-effective solution processability[1].Thanks to scientists'tremendous efforts,the external quantum efficiencies(EQEs)for the state-of-the-art PeLEDs emitting near-infrared and green light have reached 21.6%[2]and 23.4%[3],respectively.However,blue PeLEDs,as one of the essential technologies for perovskite-based high-resolution monitors and white light-ing,are still inferior to their red and green counterparts.
基金supported by the National Key R&D Pro-gram of China[grant number 2017YFE0111800]the National Natural Science Foundation of China[grant numbers 41790472 and 41822502]。
文摘Moral education is the fundamental task of education.It does not only include the inheritance of the fine traditional thoughts of the Chinese nation,but also the deepening of the new era of education concept with the new development in this changing world.Moral education has been widely implemented in the practical education process of colleges and universities and has achieved some outstanding results,but there are still some areas to be improved.Teachers in colleges and universities are the key to implement the concept of moral education,and classroom teaching is the main channel for the implementation of moral education.Therefore,teachers in colleges and universities need to deeply understand the essence and connotation of moral education,accurately grasp the practical problems existing in moral education,focus on the curriculum construction and the main channel of the classroom,and make every effort to exercise curriculum ideology and politics.
基金supported by the Natural Science Foundation of Jiangsu Province (No.BK20210751)China Postdoctoral Research Foundation (No.2022M711389)the Carbon Peak and Carbon Neutrality Technology Innovation Foundation of Jiangsu Province (No.BK20220030)。
文摘Phosphorus(P)is involved in various biochemical reactions in plant growth,so it is beneficial to plants growing in soils contaminated by metals,including cadmium(Cd).However,few studies have reported on the mechanistic roles of P in mitigating Cd toxicity to ryegrass root,and especially in alleviating the disruption of the mitochondrial function of living cells.In this study,the physiological and biochemical mechanisms associated with ryegrass growth under various Cd and P treatments were investigated using leaching and pot systems.The concentration of Cd in soil leachates showed a significantly positive relationship with redox potential(P<0.05),but negative relationship(P<0.05)with leachate pH values and dissolved organic carbon(DOC),indicating that exogenous P addition(as H_(2)PO_(4)*)may decrease Cd leaching from contaminated soil.Compared to the control(without P addition),the cumulative Cd content was reduced by 53.3%and 64.5%in the soil leachate with exogenous P application(20 mg/L and 80 mg/L),respectively.Notably,application of P decreased the Cd concentrations in the symplastic fractions and increased the Cd concentrations in the apoplastic fractions in root tips,which may help to alleviate Cd stress to the protoplast.Moreover,exogenous P was found to play a positive role in mitochondrial function and Ca^(2+)variation in root cells under Cd stress,which provides novel insights into the mechanisms of exogenous P in alleviating plant Cd injury.
基金supported by the major scientific and technological projects of Hainan Province(ZDKJ2019011)the special funding of“Blue granary”scientific and technological innovation of China(2018YFD0900301-05).
文摘The electric catfish(Malapterurus electricus),belonging to the family Malapteruridae,order Siluriformes(Actinopterygii:Ostariophysi),is one of the six branches that has independently evolved electrical organs.We assembled a 796.75 Mb M.electricus genome and anchored 88.72%sequences into 28 chromosomes.Gene family analysis revealed 295 expanded gene families that were enriched on functions related to glutamate receptors.Convergent evolutionary analyses of electric organs among different lineage of electric fishes further revealed that the coding gene of rho guanine nucleotide exchange factor 4-like(arhgef4),which is associated with G-protein coupled receptor(GPCR)signaling pathway,underwent adaptive parallel evolution.Gene identification suggests visual degradation in catfishes,and an important role for taste in environmental adaptation.Our findings fill in the genomic data for a branch of electric fish and provide a relevant genetic basis for the adaptive evolution of Siluriformes.
基金financialy supported by the National Key Research and Development Program of China(2022YFF1003402)the National Natural Science Foundation of China(32172045)+1 种基金the National Animal and Plant Transgenic Project(2016ZX08009001)the Natural Science Foundation of Ningxia Province(2022AAC02056)。
文摘Drought is a major environmental stress limiting global wheat(Triticum aestivum)production.Exploring drought tolerance genes is important for improving drought adaptation in this crop.Here,we cloned and characterized TaTIP41,a novel drought tolerance gene in wheat.TaTIP41 is a putative conserved component of target of rapamycin(TOR)signaling,and the Ta TIP41 homoeologs were expressed in response to drought stress and abscisic acid(ABA).The overexpression of Ta TIP41 enhanced drought tolerance and the ABA response,including ABA-induced stomatal closure,while its downregulation using RNA interference(RNAi)had the opposite effect.Furthermore,Ta TIP41 physically interacted with TaTAP46,another conserved component of TOR signaling.Like TaTIP41,TaTAP46 positively regulated drought tolerance.Furthermore,TaTIP41 and TaTAP46 interacted with type-2A protein phosphatase(PP2A)catalytic subunits,such as TaPP2A-2,and inhibited their enzymatic activities.Silencing TaPP2A-2 improved drought tolerance in wheat.Together,our findings provide new insights into the roles of TaTIP41 and TaTAP46 in the drought tolerance and ABA response in wheat,and their potential application in improving wheat environmental adaptability.
基金supported by the National Key Research and Development Program of China(No.2021YFB3702603)the National Natural Science Foundation of China(No.52174377)the Research Fund of the State Key Laboratory of Solidifcation Processing(NPU),China(Grant No.2022-TS-06)。
文摘TiAl alloys are susceptible to cracks during electron beam welding because their limited ductility cannot accommodate the stress generated under fast cooling rate.In this work,pre-heating and post-heating via defocused electron beam were used to obtain well-welded joints without cracks.Lower crack sensitivity of joints was attributed to the microstructure evolution to obtain more ability of stress accommodation with the increasing heating beam current and heating time.Long-time pre-heating of 5 min and post-heating of 12 min led to reduced volume fraction of residualβ0 phase with the growth ofα2/γlamellar colonies in the fusion zone(FZ).The refined microstructure of FZ contributed to the highest hardness of the FZ,and the fracture happened at the base material(BM)in tensile tests,indicating that the tensile properties of the welding seam surpassed that of the BM.This work provides an effective way to obtain TiAl joints with better mechanical properties of the welding seam than that of the BM,which is a breakthrough in the welding of TiAl alloys.
文摘A quantitative method for clopidogrel using online-SPE tandem LC–MS/MS was developed and fully validated according to the well-established FDA guidelines.The method achieves adequate sensitivity for pharmacokinetic studies,with lower limit of quantifications(LLOQs)as low as 10 pg/m L.Chromatographic separations were performed on reversed phase columns Kromasil Eternity-2.5-C18-UHPLC for both methods.Positive electrospray ionization in multiple reaction monitoring(MRM)mode was employed for signal detection and a deuterated analogue(clopidogrel-d_4)was used as internal standard(IS).Adjustments in sample preparation,including introduction of an online-SPE system proved to be the most effective method to solve the analyte back-conversion in clinical samples.Pooled clinical samples(two levels)were prepared and successfully used as real-sample quality control(QC)in the validation of back-conversion testing under different conditions.The result showed that the real samples were stable in room temperature for 24 h.Linearity,precision,extraction recovery,matrix effect on spiked QC samples and stability tests on both spiked QCs and real sample QCs stored in different conditions met the acceptance criteria.This online-SPE method was successfully applied to a bioequivalence study of75 mg single dose clopidogrel tablets in 48 healthy male subjects.
基金supported financially by the National Magnetic Confinement Fusion Program of China (Nos.2014GB120000 and2014GB104003)the National Natural Science Foundation of China (No.51571026)
文摘Dissimilar high-energy beam(HEB)welding is necessary in many industrial applications.Different composition of heat-affected zone(HAZ)and weld metal(WM)lead to variation in mechanical properties within the dissimilar joint,which determines the performance of the welded structure.In the present study,appropriate filler material was used during electron beam welding(EBW)to obtain a reliable dissimilar joint between reduced-activation ferritic-martensitic(RAFM)steel and 316L austenitic stainless steel.It was observed that the layered structure occurred in the weld metal with 310S filler(310S-WM),which had the inferior resistance to thermal disturbance,leading to severe hardening of 310S-WM after one-step tempering treatment.To further ameliorate the joint inhomogeneity,two-step heat treatment processes were imposed to the joints and optimized.δ-ferrite in the layered structure transformed intoγ-phase in the first-step normalizing and remained stable during cooling.In the second-step of tempering,tempered martensite was obtained in the HAZ of the RAFM steel,while the microstructure of 310S-WM was not affected.Thus,the optimized properties for HAZ and 310S-WM in dissimilar welded joint was both obtained by a two-step heat treatment.The creep failure position of two dissimilar joints both occurred in CLAM-BM.
基金This study was supported by the National Natural Science Foundation of China(grant numbers:81870747,81860194,and 31771619)Beijing Municipal Natural Science Foundation(grant number:7182184).
文摘The Patched 1(PTCH1)gene encodes a membrane receptor involved in the Hedge-hog(Hh)signaling pathway,an abnormal state of which may result in congenital defects or hu-man tumors.In this study,we conducted whole-exome sequencing on a three-generation Chinese family characterized with variable penetrance of orofacial clefts.A rare heterozygous variant in the PTCH1 gene(c.2833C>T p.R945X)was identified as a disease-associated mutation.Structural modeling revealed a truncation starting from the middle of the second extracellular domain of PTCH1 protein.This may damage its ligand recognition and sterol transportation abilities,thereby affecting the Hh signaling pathway.Biochemical assays indi-cated that the R945X protein had reduced stability compared to the wild-type in vitro.In addi-tion,we reviewed the locations and mutation types of PTCH1 variants in individuals with clefting phenotypes,and analyzed the associations between clefts and locations or types of variants within PTCH1.Our findings provide further evidence that PTCH1 variants result in or-ofacial clefts,and contributed to genetic counseling and clinical surveillance in this family.
