The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycle...The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition outcomes.Using China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous effects.We exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition outcomes.Our results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of age.Specifically,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage points.Additional analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition outcomes.We also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor areas.Our findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality.展开更多
The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)batteries.To simultaneously address such issues,monodispers...The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)batteries.To simultaneously address such issues,monodispersed Nb N quantum dots anchored on nitrogen-doped hollow carbon nanorods(NbN@NHCR)are elaborately developed as efficient Li PSs immobilizer and Li stabilizer for high-performance Li-S full batteries.Density functional theory(DFT)calculations and experimental characterizations demonstrate that the sulfiphilic and lithiophilic NbN@NHCR hybrid can not only efficiently immobilize the soluble Li PSs and facilitate diffusion-conversion kinetics for alleviating the shuttling effect,but also homogenize the distribution of Li+ions and regulate uniform Li deposition for suppressing Li-dendrite growth.As a result,the assembled Li-S full batteries(NbN@NHCR-S||Nb N@NHCR-Li)deliver excellent long-term cycling stability with a low decay rate of 0.031%per cycle over 1000 cycles at high rate of 2 C.Even at a high S loading of 5.8 mg cm^(-2)and a low electrolyte/sulfur ratio of 5.2μL mg^(-1),a large areal capacity of 6.2 mA h cm^(-2)can be achieved in Li-S pouch cell at 0.1 C.This study provides a new perspective via designing a dual-functional sulfiphilic and lithiophilic hybrid to address serious issues of the shuttle effect of S cathode and dendrite growth of Li anode.展开更多
The development of efficient single-atom catalysts(SACs) for the oxygen reduction reaction(ORR)remains a formidable challenge,primarily due to the symmetric charge distribution of metal singleatom sites(M-N_(4)).To ad...The development of efficient single-atom catalysts(SACs) for the oxygen reduction reaction(ORR)remains a formidable challenge,primarily due to the symmetric charge distribution of metal singleatom sites(M-N_(4)).To address such issue,herein,Fe-N_(x) sites coupled synergistic catalysts fabrication strategy is presented to break the uniform electronic distribution,thus enhancing the intrinsic catalytic activity.Precisely,atomically dispersed Fe-N_(x) sites supported on N/S-doped mesoporous carbon(NSC)coupled with FeS@C core-shell nanoparticles(FAS-NSC@950) is synthesized by a facile hydrothermal reaction and subsequent pyrolysis.Due to the presence of an in situ-grown conductive graphitic layer(shell),the FeS nanoparticles(core) effectively adjust the electronic structure of single-atom Fe sites and facilitate the ORR kinetics via short/long-range coupling interactions.Consequently,FAS-NSC@950displays a more positive half-wave potential(E_(1/2)) of 0.871 V with a significantly boosted ORR kinetics(Tafel slope=52.2 mV dec^(-1)),outpacing the commercial Pt/C(E_(1/2)=0.84 V and Tafel slope=54.6 mV dec^(-1)).As a bifunctional electrocatalyst,it displays a smaller bifunctional activity parameter(ΔE) of 0.673 V,surpassing the Pt/C-RuO_(2) combination(ΔE=0.724 V).Besides,the FAS-NSC@950-based zincair battery(ZAB) displays superior power density,specific capacity,and long-term cycling performance to the Pt/C-Ir/C-based ZAB.This work significantly contributes to the field by offering a promising strategy to enhance the catalytic activity of SACs for ORR,with potential implications for energy conversion and storage technologies.展开更多
This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volu...This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volume fraction of constituent phase or total mass,as well as the local volume fraction of all phases.The original optimization problem with numerous constraints is converted into a box-constrained optimization problem by incorporating all constraints to the augmented Lagrangian function,avoiding the parameter dependence in the conventional aggregation process.Furthermore,the local volume percentage can be precisely satisfied.The effects including the globalmass bound,the influence radius and local volume percentage on final designs are exploited through numerical examples.The numerical results also reveal that porous structures keep a balance between the bulk design and periodic design in terms of the resulting compliance.All results,including those for irregular structures andmultiple volume fraction constraints,demonstrate that the proposedmethod can provide an efficient solution for multiple material infill structures.展开更多
A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax depositi...A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.展开更多
Oil and gas pipelines are affected by many factors,such as pipe wall thinning and pipeline rupture.Accurate prediction of failure pressure of oil and gas pipelines can provide technical support for pipeline safety man...Oil and gas pipelines are affected by many factors,such as pipe wall thinning and pipeline rupture.Accurate prediction of failure pressure of oil and gas pipelines can provide technical support for pipeline safety management.Aiming at the shortcomings of the BP Neural Network(BPNN)model,such as low learning efficiency,sensitivity to initial weights,and easy falling into a local optimal state,an Improved Sparrow Search Algorithm(ISSA)is adopted to optimize the initial weights and thresholds of BPNN,and an ISSA-BPNN failure pressure prediction model for corroded pipelines is established.Taking 61 sets of pipelines blasting test data as an example,the prediction model was built and predicted by MATLAB software,and compared with the BPNN model,GA-BPNN model,and SSA-BPNN model.The results show that the MAPE of the ISSA-BPNN model is 3.4177%,and the R2 is 0.9880,both of which are superior to its comparison model.Using the ISSA-BPNN model has high prediction accuracy and stability,and can provide support for pipeline inspection and maintenance.展开更多
The Rana chensinensis species group is widely distributed throughout North China.However,its taxonomy and composition remain controversial.In recent field investigations of the Taihang Mountains,a series of Rana speci...The Rana chensinensis species group is widely distributed throughout North China.However,its taxonomy and composition remain controversial.In recent field investigations of the Taihang Mountains,a series of Rana specimens were collected,which were once identified as R.chensinensis.However,these samples showed significant differences from R.chensinensis of the type locality(Shaanxi Province in the Qinling Mountains)in both morphology and genetics.In this paper,based on analyses of seventeen geographic populations from the Taihang and Qinling Mountains,we describe a new species(namely R.taihangensis sp.nov.)in the R.chensinensis species group.A phylogenetic analysis of the R.chensinensis species group based on mitochondrial genes—COI,16S rRNA and Cytb—revealed the monophyly of the cryptic species,which formed the sister taxon to R.kukunoris.Morphological comparisons indicated that the cryptic species can be distinguished from its congeners by a combination of characteristics.Additionally,the distribution patterns of the Rana species in North China were clarified.The populations of the southwestern Taihang Mountains,Xiaoqinling Mountains,and Funiu Mountains in Henan Province remain R.chensinensis,whereas the populations recorded as R.chensinensis in Beijing City,Hebei Province,and the southeastern Taihang Mountains of Henan Province should be revised as R.taihangensis sp.nov.展开更多
Mercury is a ubiquitous contaminant known to accumulate in wildlife,particularly bird species at higher trophic levels.Knowledge of tissue-specific Hg distributions aids our understanding of Hg bioaccumulation in orga...Mercury is a ubiquitous contaminant known to accumulate in wildlife,particularly bird species at higher trophic levels.Knowledge of tissue-specific Hg distributions aids our understanding of Hg bioaccumulation in organisms.In this study,one adult and three juvenile Collared Scops Owls(Otus lettia)were studied to elucidate the bioaccumulation of Hg in body tissues.Six tissues and organs(feathers,nails,heart,liver,gizzard,and muscle),as well as gastric contents,were examined for total Hg(THg)and methylmercury(MeHg)contents,Hg isotopic compositions including mass-dependent fractionation(MDF;δ202Hg)and mass-independent fractionation(MIF;Δ199Hg andΔ201Hg),and C(δ13C)and N(δ15N)isotopic compositions.Tissue-specific THg and MeHg concentrations in the adult were in the ranges of 150–1360 ng/g and17–1060 ng/g,and lower in the juveniles at 91–419 ng/g and 67–350 ng/g,respectively.Theδ^(202)Hg values in the adult were strongly negative at-1.75‰±0.17‰compared with the juveniles at-0.99‰±0.25‰.The adult exhibited lower MIF values than the juveniles,at0.23‰±0.07‰forΔ^(199)Hg and 0.2‰±0.11‰forΔ^(201)Hg,comparedwith0.81‰±0.09‰and0.66‰±0.07‰,respectively.The lower adult MDF and MIF values suggest that the adult tended to accumulate negative Hg isotopes but the juvenile's positive Hg isotopes.Differences between adult and juvenile tissue Hg concentrations indicate that metabolic processes play an important role in Hg accumulation.展开更多
Objective Diminished ovarian reserve(DOR)can lead to early menopause,poor fecundity,and an increased risk of disorders such as osteoporosis,cardiovascular disease,and cognitive impairment,seriously affecting the physi...Objective Diminished ovarian reserve(DOR)can lead to early menopause,poor fecundity,and an increased risk of disorders such as osteoporosis,cardiovascular disease,and cognitive impairment,seriously affecting the physical and mental health of women.There is still no safe and effective strategy or method to combat DOR.We have developed a novel Chinese herbal formula,Tongji anti-ovarian aging 101(TJAOA101),to treat DOR.However,its safety and efficacy need to be further validated.Methods In this prospective and pre-post clinical trial,100 eligible patients aged 18–45 diagnosed with DOR will be recruited.All participants receive TJAOA101 twice a day for 3 months.Then,comparisons before and after treatment will be analyzed,and the outcomes,including anti-mullerian hormone(AMH)and follicle-stimulating hormone(FSH)levels and the antral follicle count(AFC),the recovery rate of menopause,and the Kupperman index(KMI),will be assessed at baseline,every month during medication(the intervention period),and 1,3 months after medication(the follow-up period).Assessments for adverse events will be performed during the intervention and follow-up periods.Conclusion A multicenter,prospective study will be conducted to further confirm the safety and efficacy of TJAOA101 in treating DOR and to provide new therapeutic strategies for improving the quality of life in DOR patients.展开更多
Vector accelerometer has attracted much attention for its great application potential in underground seismic signal measurement. We propose and demonstrate a novel vector accelerometer based on the three fiber Bragg g...Vector accelerometer has attracted much attention for its great application potential in underground seismic signal measurement. We propose and demonstrate a novel vector accelerometer based on the three fiber Bragg gratings(FBGs)embedded in a silicone rubber compliant cylinder at 120° distributed uniformly. The accelerometer is capable of detecting the orientation of vibration with a range of 0°–360° and the acceleration through monitoring the central wavelength shifts of three FBGs simultaneously. The experimental results show that the natural frequency of the accelerometer is about 85 Hz, and the sensitivity is 84.21 pm/g in the flat range of 20 Hz–60 Hz. Through experimental calibration, the designed accelerometer can accurately obtain vibration vector information, including vibration orientation and acceleration. In addition, the range of resonant frequency and sensitivity can be expanded by adjusting the hardness of the silicone rubber materials. Due to the characteristics of small size and orientation recognition, the accelerometer can be applied to low-frequency vibration acceleration vector measurement in narrow spaces.展开更多
BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(P...BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(PD-L1),which determines the clinical therapeutic efficacy of MSCs for inflammatory or immune diseases.In MSCs,interferon-gamma(IFN-γ)is a key inducer of PD-L1 expression,which is synergistically enhanced by tumor necrosis factor-alpha(TNF-α);however,the underlying mechanism is unclear.AIM To reveal the mechanism of pretreated MSCs express high PD-L1 and explore the application of pretreated MSCs in ulcerative colitis.METHODS We assessed PD-L1 expression in human umbilical-cord-derived MSCs(hUC-MSCs)induced by IFN-γand TNF-α,alone or in combination.Additionally,we performed signal pathway inhibitor experiments as well as RNA interference experiments to elucidate the molecular mechanism by which IFN-γalone or in combination with TNF-αinduces PD-L1 expression.Moreover,we used luciferase reporter gene experiments to verify the binding sites of the transcription factors of each signal transduction pathway to the targeted gene promoters.Finally,we evaluated the immunosuppressive capacity of hUC-MSCs treated with IFN-γand TNF-αin both an in vitro mixed lymphocyte culture assay,and in vivo in mice with dextran sulfate sodium-induced acute colitis.RESULTS Our results suggest that IFN-γinduction alone upregulates PD-L1 expression in hUC-MSCs while TNF-αalone does not,and that the co-induction of IFN-γand TNF-αpromotes higher expression of PD-L1.IFN-γinduces hUCMSCs to express PD-L1,in which IFN-γactivates the JAK/STAT1 signaling pathway,up-regulates the expression of the interferon regulatory factor 1(IRF1)transcription factor,promotes the binding of IRF1 and the PD-L1 gene promoter,and finally promotes PD-L1 mRNA.Although TNF-αalone did not induce PD-L1 expression in hUCMSCs,the addition of TNF-αsignificantly enhanced IFN-γ-induced JAK/STAT1/IRF1 activation.TNF-αupregulated IFN-γreceptor expression through activation of the nuclear factor kappa-B signaling pathway,which significantly enhanced IFN-γsignaling.Finally,co-induced hUC-MSCs have a stronger inhibitory effect on lymphocyte proliferation,and significantly ameliorate weight loss,mucosal damage,inflammatory cell infiltration,and up-regulation of inflammatory factors in colitis mice.CONCLUSION Overall,our results suggest that IFN-γand TNF-αenhance both the immunosuppressive ability of hUC-MSCs and their efficacy in ulcerative colitis by synergistically inducing high expression of PD-L1.展开更多
Deploying service nodes hierarchically at the edge of the network can effectively improve the service quality of offloaded task requests and increase the utilization of resources.In this paper,we study the task schedu...Deploying service nodes hierarchically at the edge of the network can effectively improve the service quality of offloaded task requests and increase the utilization of resources.In this paper,we study the task scheduling problem in the hierarchically deployed edge cloud.We first formulate the minimization of the service time of scheduled tasks in edge cloud as a combinatorial optimization problem,blue and then prove the NP-hardness of the problem.Different from the existing work that mostly designs heuristic approximation-based algorithms or policies to make scheduling decision,we propose a newly designed scheduling policy,named Joint Neural Network and Heuristic Scheduling(JNNHSP),which combines a neural network-based method with a heuristic based solution.JNNHSP takes the Sequence-to-Sequence(Seq2Seq)model trained by Reinforcement Learning(RL)as the primary policy and adopts the heuristic algorithm as the auxiliary policy to obtain the scheduling solution,thereby achieving a good balance between the quality and the efficiency of the scheduling solution.In-depth experiments show that compared with a variety of related policies and optimization solvers,JNNHSP can achieve better performance in terms of scheduling error ratio,the degree to which the policy is affected by re-sources limitations,average service latency,and execution efficiency in a typical hierarchical edge cloud.展开更多
In traction application,speed range of motor is an important index for motor drives.In AC motor control,the maximum speed of the motor is limited by the output voltage capability of the traditional three-phase inverte...In traction application,speed range of motor is an important index for motor drives.In AC motor control,the maximum speed of the motor is limited by the output voltage capability of the traditional three-phase inverter with star connenction of windings.Switching the star connection to delta connection in high-speed range can extend the speed range.In order to extend the speed operation region,star-delta switch proposed by many literatures relies on mechanical relay,which needs a dead zone of tens of milliseconds and seriously affects torque output.Besides,the traditional method will cause current overshoot during the switch transient process,decreasing the device security and reliability.Aiming at the defects existing in the star-delta hard switching,this paper proposes a star-delta soft switching method.Without adding extra power electronics devices,DC-bus capacitor is used to provide the path of zero axis current in the transient process,which helps to achieve the smooth torque output and zero current switch in the transient.Experiments have been done to validate the performance of the proposed method.The switching transient from star to delta connection in the motor drive can be much more stable than hard switching method.展开更多
Beishashen(BSS)and Maidong(MD)are commonly used Medicine right for the treatment of non-small cell lung cancer(NSCLC),but their specific mechanism of action is not clear.In this study,network pharmacology and molecula...Beishashen(BSS)and Maidong(MD)are commonly used Medicine right for the treatment of non-small cell lung cancer(NSCLC),but their specific mechanism of action is not clear.In this study,network pharmacology and molecular docking techniques were used to investigate the molecular mechanisms of the therapeutic effects of BSS-MD on NSCLC and to experimentally validate some of the targets.The network pharmacology approach,including active ingredient and target screening,drug-compound-target network construction,protein-protein interaction(PPI)network,enrichment analysis,and molecular docking,was used to investigate the mechanism of action of Beisashen and Maitong on NSCLC.First,the active components of BSS-MD and their targets were predicted,of which 423 targets interacted with NSCLC targets.Then,network pharmacology showed that Stigmasterol,Quercetin,Alloisoimperatorin,Isoimperatorin,Beta-sitosterol were the core components of BSS-MD,and PLK1,HSP90AB1,and CDK1 were the key therapeutic targets.KEGG enrichment analysis indicated that the mechanism of action of BSS-MD in NSCLC treatment was related to the cell cycle.Then we further performed experimental validation.CCK-8 assay showed that BSS-MD inhibited LEWIS cell viability and promoted apoptosis in a dose-dependent manner.qPCR assay,immunofluorescence,and protein blotting experiments demonstrated that compared with the control group and the control group,the expression of PLK1,HSP90AB1,and CDK1 mRNAs and proteins were reduced in the treatment group(P<0.01).Therefore,we conclude that BSS-MD can block cell cycle progression by inhibiting the expression of PLK1,CDK1,and HSP90AB1 mRNAs and proteins to inhibit lung cancer cell growth and promote apoptosis,and emphasize that BSS-MD are promising adjuvants for NSCLC treatment.展开更多
The tumor microenvironment(TME)plays a crucial role in facilitating tumorigenesis and progression.Consequently,there is significant research interest within the oncology community in developing interventions that targ...The tumor microenvironment(TME)plays a crucial role in facilitating tumorigenesis and progression.Consequently,there is significant research interest within the oncology community in developing interventions that target the TME.Extensive research has been conducted on the mechanism of traditional Chinese medicine(TCM)in tumor therapy,revealing notable similarities between its theoretical framework and that of the TME.TCM has the ability to regulate various components of the microenvironment,including the modulation of proportions of T cell subsets,enhancement of the quantity and activity of NK cells,regulation of polarization of tumor-associated macrophages,suppression of expression of myeloid-derived suppressor cells,reduction of accumulation of tumor-associated endothelial cells,downregulation of the quantity and function of tumor-associated fibroblasts,and modulation of the architecture of the extracellular matrix.These multifaceted interventions ultimately lead to the attainment of anti-tumor objectives.This comprehensive review encompasses a thorough analysis of relevant literature from both domestic and international sources,with a specific emphasis on elucidating the mechanisms through which TCM compound formulas,single drugs,and monomeric components regulate the TME.展开更多
The reported cases of food allergies are steadily increasing.With the invention of more novel foods,new and unfamiliar allergens are being introduced into our diets,which raises concerns about the potential risk of no...The reported cases of food allergies are steadily increasing.With the invention of more novel foods,new and unfamiliar allergens are being introduced into our diets,which raises concerns about the potential risk of novel food allergies.The purpose of this review is to assess the allergenic risks associated with novel food components,strategies for assessing risk in relation to novel food allergens,and current regulations for managing food allergens in novel food products.展开更多
基金The authors are grateful for support from the National Social Science Fund of China(21AJL015).
文摘The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition outcomes.Using China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous effects.We exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition outcomes.Our results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of age.Specifically,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage points.Additional analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition outcomes.We also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor areas.Our findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality.
基金supported by the open research fund of Songshan Lake Materials Laboratory (2022SLABFN26)the National Natural Science Foundation of China (21773024)+1 种基金the Sichuan Science and Technology program (2020YJ0324,2020YJ0262)the Reformation and Development Funds for Local Region Universities from China Government in 2020 (ZCKJ 2020-11)。
文摘The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)batteries.To simultaneously address such issues,monodispersed Nb N quantum dots anchored on nitrogen-doped hollow carbon nanorods(NbN@NHCR)are elaborately developed as efficient Li PSs immobilizer and Li stabilizer for high-performance Li-S full batteries.Density functional theory(DFT)calculations and experimental characterizations demonstrate that the sulfiphilic and lithiophilic NbN@NHCR hybrid can not only efficiently immobilize the soluble Li PSs and facilitate diffusion-conversion kinetics for alleviating the shuttling effect,but also homogenize the distribution of Li+ions and regulate uniform Li deposition for suppressing Li-dendrite growth.As a result,the assembled Li-S full batteries(NbN@NHCR-S||Nb N@NHCR-Li)deliver excellent long-term cycling stability with a low decay rate of 0.031%per cycle over 1000 cycles at high rate of 2 C.Even at a high S loading of 5.8 mg cm^(-2)and a low electrolyte/sulfur ratio of 5.2μL mg^(-1),a large areal capacity of 6.2 mA h cm^(-2)can be achieved in Li-S pouch cell at 0.1 C.This study provides a new perspective via designing a dual-functional sulfiphilic and lithiophilic hybrid to address serious issues of the shuttle effect of S cathode and dendrite growth of Li anode.
基金financially supported by the National Natural Science Foundation of China(21773024)the Natural Science Foundation of Sichuan Province of China(2023NSFC0084)the China Postdoctoral Science Foundation(2019M663469)。
文摘The development of efficient single-atom catalysts(SACs) for the oxygen reduction reaction(ORR)remains a formidable challenge,primarily due to the symmetric charge distribution of metal singleatom sites(M-N_(4)).To address such issue,herein,Fe-N_(x) sites coupled synergistic catalysts fabrication strategy is presented to break the uniform electronic distribution,thus enhancing the intrinsic catalytic activity.Precisely,atomically dispersed Fe-N_(x) sites supported on N/S-doped mesoporous carbon(NSC)coupled with FeS@C core-shell nanoparticles(FAS-NSC@950) is synthesized by a facile hydrothermal reaction and subsequent pyrolysis.Due to the presence of an in situ-grown conductive graphitic layer(shell),the FeS nanoparticles(core) effectively adjust the electronic structure of single-atom Fe sites and facilitate the ORR kinetics via short/long-range coupling interactions.Consequently,FAS-NSC@950displays a more positive half-wave potential(E_(1/2)) of 0.871 V with a significantly boosted ORR kinetics(Tafel slope=52.2 mV dec^(-1)),outpacing the commercial Pt/C(E_(1/2)=0.84 V and Tafel slope=54.6 mV dec^(-1)).As a bifunctional electrocatalyst,it displays a smaller bifunctional activity parameter(ΔE) of 0.673 V,surpassing the Pt/C-RuO_(2) combination(ΔE=0.724 V).Besides,the FAS-NSC@950-based zincair battery(ZAB) displays superior power density,specific capacity,and long-term cycling performance to the Pt/C-Ir/C-based ZAB.This work significantly contributes to the field by offering a promising strategy to enhance the catalytic activity of SACs for ORR,with potential implications for energy conversion and storage technologies.
基金This study is financially supported by StateKey Laboratory of Alternate Electrical Power System with Renewable Energy Sources(Grant No.LAPS22012).
文摘This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volume fraction of constituent phase or total mass,as well as the local volume fraction of all phases.The original optimization problem with numerous constraints is converted into a box-constrained optimization problem by incorporating all constraints to the augmented Lagrangian function,avoiding the parameter dependence in the conventional aggregation process.Furthermore,the local volume percentage can be precisely satisfied.The effects including the globalmass bound,the influence radius and local volume percentage on final designs are exploited through numerical examples.The numerical results also reveal that porous structures keep a balance between the bulk design and periodic design in terms of the resulting compliance.All results,including those for irregular structures andmultiple volume fraction constraints,demonstrate that the proposedmethod can provide an efficient solution for multiple material infill structures.
文摘A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.
文摘Oil and gas pipelines are affected by many factors,such as pipe wall thinning and pipeline rupture.Accurate prediction of failure pressure of oil and gas pipelines can provide technical support for pipeline safety management.Aiming at the shortcomings of the BP Neural Network(BPNN)model,such as low learning efficiency,sensitivity to initial weights,and easy falling into a local optimal state,an Improved Sparrow Search Algorithm(ISSA)is adopted to optimize the initial weights and thresholds of BPNN,and an ISSA-BPNN failure pressure prediction model for corroded pipelines is established.Taking 61 sets of pipelines blasting test data as an example,the prediction model was built and predicted by MATLAB software,and compared with the BPNN model,GA-BPNN model,and SSA-BPNN model.The results show that the MAPE of the ISSA-BPNN model is 3.4177%,and the R2 is 0.9880,both of which are superior to its comparison model.Using the ISSA-BPNN model has high prediction accuracy and stability,and can provide support for pipeline inspection and maintenance.
基金supported by the Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China(2019HJ2096001006)China Biodiversity Observation Networks(Sino BON)+2 种基金the National Natural Science Foundation of China(31872220,U21A20192 and 31572245)the Natural Science Founda tion of Henan Province(202300410222)the Second National Survey of Terrestrial Wildlife Resources Project of the National Forestry and Grassland Bureau of China.
文摘The Rana chensinensis species group is widely distributed throughout North China.However,its taxonomy and composition remain controversial.In recent field investigations of the Taihang Mountains,a series of Rana specimens were collected,which were once identified as R.chensinensis.However,these samples showed significant differences from R.chensinensis of the type locality(Shaanxi Province in the Qinling Mountains)in both morphology and genetics.In this paper,based on analyses of seventeen geographic populations from the Taihang and Qinling Mountains,we describe a new species(namely R.taihangensis sp.nov.)in the R.chensinensis species group.A phylogenetic analysis of the R.chensinensis species group based on mitochondrial genes—COI,16S rRNA and Cytb—revealed the monophyly of the cryptic species,which formed the sister taxon to R.kukunoris.Morphological comparisons indicated that the cryptic species can be distinguished from its congeners by a combination of characteristics.Additionally,the distribution patterns of the Rana species in North China were clarified.The populations of the southwestern Taihang Mountains,Xiaoqinling Mountains,and Funiu Mountains in Henan Province remain R.chensinensis,whereas the populations recorded as R.chensinensis in Beijing City,Hebei Province,and the southeastern Taihang Mountains of Henan Province should be revised as R.taihangensis sp.nov.
基金supported by National Natural Science Foundation of China(NSFC No.42103080)。
文摘Mercury is a ubiquitous contaminant known to accumulate in wildlife,particularly bird species at higher trophic levels.Knowledge of tissue-specific Hg distributions aids our understanding of Hg bioaccumulation in organisms.In this study,one adult and three juvenile Collared Scops Owls(Otus lettia)were studied to elucidate the bioaccumulation of Hg in body tissues.Six tissues and organs(feathers,nails,heart,liver,gizzard,and muscle),as well as gastric contents,were examined for total Hg(THg)and methylmercury(MeHg)contents,Hg isotopic compositions including mass-dependent fractionation(MDF;δ202Hg)and mass-independent fractionation(MIF;Δ199Hg andΔ201Hg),and C(δ13C)and N(δ15N)isotopic compositions.Tissue-specific THg and MeHg concentrations in the adult were in the ranges of 150–1360 ng/g and17–1060 ng/g,and lower in the juveniles at 91–419 ng/g and 67–350 ng/g,respectively.Theδ^(202)Hg values in the adult were strongly negative at-1.75‰±0.17‰compared with the juveniles at-0.99‰±0.25‰.The adult exhibited lower MIF values than the juveniles,at0.23‰±0.07‰forΔ^(199)Hg and 0.2‰±0.11‰forΔ^(201)Hg,comparedwith0.81‰±0.09‰and0.66‰±0.07‰,respectively.The lower adult MDF and MIF values suggest that the adult tended to accumulate negative Hg isotopes but the juvenile's positive Hg isotopes.Differences between adult and juvenile tissue Hg concentrations indicate that metabolic processes play an important role in Hg accumulation.
基金supported by grants from the National Natural Science Foundation of China(No.82001498 and No.82002768)the Natural Science Foundation of Hubei Province(No.2020CFB544)The Clinical Research Pilot Project of Tongji Hospital,Huazhong University of Science and Technology(No.2019CR205).
文摘Objective Diminished ovarian reserve(DOR)can lead to early menopause,poor fecundity,and an increased risk of disorders such as osteoporosis,cardiovascular disease,and cognitive impairment,seriously affecting the physical and mental health of women.There is still no safe and effective strategy or method to combat DOR.We have developed a novel Chinese herbal formula,Tongji anti-ovarian aging 101(TJAOA101),to treat DOR.However,its safety and efficacy need to be further validated.Methods In this prospective and pre-post clinical trial,100 eligible patients aged 18–45 diagnosed with DOR will be recruited.All participants receive TJAOA101 twice a day for 3 months.Then,comparisons before and after treatment will be analyzed,and the outcomes,including anti-mullerian hormone(AMH)and follicle-stimulating hormone(FSH)levels and the antral follicle count(AFC),the recovery rate of menopause,and the Kupperman index(KMI),will be assessed at baseline,every month during medication(the intervention period),and 1,3 months after medication(the follow-up period).Assessments for adverse events will be performed during the intervention and follow-up periods.Conclusion A multicenter,prospective study will be conducted to further confirm the safety and efficacy of TJAOA101 in treating DOR and to provide new therapeutic strategies for improving the quality of life in DOR patients.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61927812, 61735014, and 62105261)。
文摘Vector accelerometer has attracted much attention for its great application potential in underground seismic signal measurement. We propose and demonstrate a novel vector accelerometer based on the three fiber Bragg gratings(FBGs)embedded in a silicone rubber compliant cylinder at 120° distributed uniformly. The accelerometer is capable of detecting the orientation of vibration with a range of 0°–360° and the acceleration through monitoring the central wavelength shifts of three FBGs simultaneously. The experimental results show that the natural frequency of the accelerometer is about 85 Hz, and the sensitivity is 84.21 pm/g in the flat range of 20 Hz–60 Hz. Through experimental calibration, the designed accelerometer can accurately obtain vibration vector information, including vibration orientation and acceleration. In addition, the range of resonant frequency and sensitivity can be expanded by adjusting the hardness of the silicone rubber materials. Due to the characteristics of small size and orientation recognition, the accelerometer can be applied to low-frequency vibration acceleration vector measurement in narrow spaces.
基金Supported by the National Natural Science Foundation of China,No.81871568,No.32100643COVID-19 Infection and Prevention Emergency Special Project of Chongqing Education Commission,No.KYYJ202009.
文摘BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(PD-L1),which determines the clinical therapeutic efficacy of MSCs for inflammatory or immune diseases.In MSCs,interferon-gamma(IFN-γ)is a key inducer of PD-L1 expression,which is synergistically enhanced by tumor necrosis factor-alpha(TNF-α);however,the underlying mechanism is unclear.AIM To reveal the mechanism of pretreated MSCs express high PD-L1 and explore the application of pretreated MSCs in ulcerative colitis.METHODS We assessed PD-L1 expression in human umbilical-cord-derived MSCs(hUC-MSCs)induced by IFN-γand TNF-α,alone or in combination.Additionally,we performed signal pathway inhibitor experiments as well as RNA interference experiments to elucidate the molecular mechanism by which IFN-γalone or in combination with TNF-αinduces PD-L1 expression.Moreover,we used luciferase reporter gene experiments to verify the binding sites of the transcription factors of each signal transduction pathway to the targeted gene promoters.Finally,we evaluated the immunosuppressive capacity of hUC-MSCs treated with IFN-γand TNF-αin both an in vitro mixed lymphocyte culture assay,and in vivo in mice with dextran sulfate sodium-induced acute colitis.RESULTS Our results suggest that IFN-γinduction alone upregulates PD-L1 expression in hUC-MSCs while TNF-αalone does not,and that the co-induction of IFN-γand TNF-αpromotes higher expression of PD-L1.IFN-γinduces hUCMSCs to express PD-L1,in which IFN-γactivates the JAK/STAT1 signaling pathway,up-regulates the expression of the interferon regulatory factor 1(IRF1)transcription factor,promotes the binding of IRF1 and the PD-L1 gene promoter,and finally promotes PD-L1 mRNA.Although TNF-αalone did not induce PD-L1 expression in hUCMSCs,the addition of TNF-αsignificantly enhanced IFN-γ-induced JAK/STAT1/IRF1 activation.TNF-αupregulated IFN-γreceptor expression through activation of the nuclear factor kappa-B signaling pathway,which significantly enhanced IFN-γsignaling.Finally,co-induced hUC-MSCs have a stronger inhibitory effect on lymphocyte proliferation,and significantly ameliorate weight loss,mucosal damage,inflammatory cell infiltration,and up-regulation of inflammatory factors in colitis mice.CONCLUSION Overall,our results suggest that IFN-γand TNF-αenhance both the immunosuppressive ability of hUC-MSCs and their efficacy in ulcerative colitis by synergistically inducing high expression of PD-L1.
基金Supported by Scientific and Technological Innovation Project of Chongqing(No.cstc2021jxjl20010)The Graduate Student Innovation Program of Chongqing University of Technology(No.clgycx-20203166,No.gzlcx20222061,No.gzlcx20223229)。
文摘Deploying service nodes hierarchically at the edge of the network can effectively improve the service quality of offloaded task requests and increase the utilization of resources.In this paper,we study the task scheduling problem in the hierarchically deployed edge cloud.We first formulate the minimization of the service time of scheduled tasks in edge cloud as a combinatorial optimization problem,blue and then prove the NP-hardness of the problem.Different from the existing work that mostly designs heuristic approximation-based algorithms or policies to make scheduling decision,we propose a newly designed scheduling policy,named Joint Neural Network and Heuristic Scheduling(JNNHSP),which combines a neural network-based method with a heuristic based solution.JNNHSP takes the Sequence-to-Sequence(Seq2Seq)model trained by Reinforcement Learning(RL)as the primary policy and adopts the heuristic algorithm as the auxiliary policy to obtain the scheduling solution,thereby achieving a good balance between the quality and the efficiency of the scheduling solution.In-depth experiments show that compared with a variety of related policies and optimization solvers,JNNHSP can achieve better performance in terms of scheduling error ratio,the degree to which the policy is affected by re-sources limitations,average service latency,and execution efficiency in a typical hierarchical edge cloud.
文摘In traction application,speed range of motor is an important index for motor drives.In AC motor control,the maximum speed of the motor is limited by the output voltage capability of the traditional three-phase inverter with star connenction of windings.Switching the star connection to delta connection in high-speed range can extend the speed range.In order to extend the speed operation region,star-delta switch proposed by many literatures relies on mechanical relay,which needs a dead zone of tens of milliseconds and seriously affects torque output.Besides,the traditional method will cause current overshoot during the switch transient process,decreasing the device security and reliability.Aiming at the defects existing in the star-delta hard switching,this paper proposes a star-delta soft switching method.Without adding extra power electronics devices,DC-bus capacitor is used to provide the path of zero axis current in the transient process,which helps to achieve the smooth torque output and zero current switch in the transient.Experiments have been done to validate the performance of the proposed method.The switching transient from star to delta connection in the motor drive can be much more stable than hard switching method.
基金This research was supported by“Zhejiang Province Chinese Medicine Science and Technology Program Key Projects”(No.2021ZZ008).
文摘Beishashen(BSS)and Maidong(MD)are commonly used Medicine right for the treatment of non-small cell lung cancer(NSCLC),but their specific mechanism of action is not clear.In this study,network pharmacology and molecular docking techniques were used to investigate the molecular mechanisms of the therapeutic effects of BSS-MD on NSCLC and to experimentally validate some of the targets.The network pharmacology approach,including active ingredient and target screening,drug-compound-target network construction,protein-protein interaction(PPI)network,enrichment analysis,and molecular docking,was used to investigate the mechanism of action of Beisashen and Maitong on NSCLC.First,the active components of BSS-MD and their targets were predicted,of which 423 targets interacted with NSCLC targets.Then,network pharmacology showed that Stigmasterol,Quercetin,Alloisoimperatorin,Isoimperatorin,Beta-sitosterol were the core components of BSS-MD,and PLK1,HSP90AB1,and CDK1 were the key therapeutic targets.KEGG enrichment analysis indicated that the mechanism of action of BSS-MD in NSCLC treatment was related to the cell cycle.Then we further performed experimental validation.CCK-8 assay showed that BSS-MD inhibited LEWIS cell viability and promoted apoptosis in a dose-dependent manner.qPCR assay,immunofluorescence,and protein blotting experiments demonstrated that compared with the control group and the control group,the expression of PLK1,HSP90AB1,and CDK1 mRNAs and proteins were reduced in the treatment group(P<0.01).Therefore,we conclude that BSS-MD can block cell cycle progression by inhibiting the expression of PLK1,CDK1,and HSP90AB1 mRNAs and proteins to inhibit lung cancer cell growth and promote apoptosis,and emphasize that BSS-MD are promising adjuvants for NSCLC treatment.
基金supported by the National Natural Science Foundation of China(No.81973771).
文摘The tumor microenvironment(TME)plays a crucial role in facilitating tumorigenesis and progression.Consequently,there is significant research interest within the oncology community in developing interventions that target the TME.Extensive research has been conducted on the mechanism of traditional Chinese medicine(TCM)in tumor therapy,revealing notable similarities between its theoretical framework and that of the TME.TCM has the ability to regulate various components of the microenvironment,including the modulation of proportions of T cell subsets,enhancement of the quantity and activity of NK cells,regulation of polarization of tumor-associated macrophages,suppression of expression of myeloid-derived suppressor cells,reduction of accumulation of tumor-associated endothelial cells,downregulation of the quantity and function of tumor-associated fibroblasts,and modulation of the architecture of the extracellular matrix.These multifaceted interventions ultimately lead to the attainment of anti-tumor objectives.This comprehensive review encompasses a thorough analysis of relevant literature from both domestic and international sources,with a specific emphasis on elucidating the mechanisms through which TCM compound formulas,single drugs,and monomeric components regulate the TME.
基金Central Government Guide Local Special Fund Project for Scientific and Technological Development of Jiangxi Province(20221ZDD02001).
文摘The reported cases of food allergies are steadily increasing.With the invention of more novel foods,new and unfamiliar allergens are being introduced into our diets,which raises concerns about the potential risk of novel food allergies.The purpose of this review is to assess the allergenic risks associated with novel food components,strategies for assessing risk in relation to novel food allergens,and current regulations for managing food allergens in novel food products.
