Unstable environments intensify the frequency of extreme disasters.Long-term climate changes can lead to agricultural and ecological degradation that threatens population sustainability.To better understand past clima...Unstable environments intensify the frequency of extreme disasters.Long-term climate changes can lead to agricultural and ecological degradation that threatens population sustainability.To better understand past climatic events and consequences,here we present a reconstruction of the self-calibrating Palmer drought severity index(scPDSI)from September to August for the desert margins of northern China,dating back to 1742.The reconstruction accounts for 42.9%of the variation of meteorological data between 1951 and 2020.Our spatial correlation analyses showed significant correlations between scPDSI,runoff,and precipitation.Over the past 279 years,the study area has undergone nine dry and eight wet periods,with the most severe climate extremes between the 1850s and 1890s.This period of prolonged drought in northeastern China coincided with the combined impacts of climatic factors and human influences,contributing to the fall of the Qing Dynasty.Analysis of periodicity and anomalies in sea surface temperatures indicate a strong association between wet and dry cycles and El Niño-Southern Oscillations.Our findings offer insights into long-term dry and wet fluctuations at the desert margins in northern China and elucidate the relationship between drought and the dynamics of civilizations.They also highlight the potential impact of extremes in climate on modern society,especially under the four projected shared socioeconomic pathways climatic scenarios,which predict worsening droughts in northern China.展开更多
Background Sex hormones play important roles in the estrus return of post-weaning sows.Previous studies have demonstrated a complex and bi-directional regulation between sex hormones and gut microbiota.However,the ext...Background Sex hormones play important roles in the estrus return of post-weaning sows.Previous studies have demonstrated a complex and bi-directional regulation between sex hormones and gut microbiota.However,the extent to which the gut microbiota affects estrus return of post-weaning sows is largely unknown.Results In this study,we first screened 207 fecal samples from well-phenotyped sows by 16S rRNA gene sequencing and identified significant associations between microbes and estrus return of post-weaning sows.Using metagenomic sequencing data from 85 fecal samples,we identified 37 bacterial species that were significantly associated with estrus return.Normally returning sows were characterized by increased abundances of L.reuteri and P.copri and decreased abundances of B.fragilis,S.suis,and B.pseudolongum.The changes in gut microbial composition significantly altered the functional capacity of steroid hormone biosynthesis in the gut microbiome.The results were confirmed in a validation cohort.Significant changes in sex steroid hormones and related compounds were found between normal and non-return sows via metabolome analysis.An integrated analysis of differential bacterial species,metagenome,and fecal metabolome provided evidence that normal return-associated bacterial species L.reuteri and Prevotella spp.participated in the degradation of pregnenolone,progesterone,and testosterone,thereby promoting estrogen biosynthesis.Furthermore,the microbial metabolites related to sow energy and nutrient supply or metabolic disorders also showed relationships with sow estrus return.Conclusions An integrated analysis of differentially abundant bacterial species,metagenome,and fecal metabolome revealed the involvement of L.reuteri and Prevotella spp.in sow estrus return.These findings provide deep insight into the role of gut microbiota in the estrus return of post-weaning sows and the complex cross-talk between gut microbiota and sex hormones,suggesting that the manipulation of the gut microbiota could be an effective strategy to improve sow estrus return after weaning.展开更多
Elucidating the effect of growth periods on the quality of calcium sulfate whiskers(CSWs)prepared from calcium sulfate dihydrate(DH)is imperative.Herein,crystal seeds and whiskers were prepared from DH in a water–gly...Elucidating the effect of growth periods on the quality of calcium sulfate whiskers(CSWs)prepared from calcium sulfate dihydrate(DH)is imperative.Herein,crystal seeds and whiskers were prepared from DH in a water–glycerol system.Longer whiskers were obtained from crystal seeds prepared via hydration of DH for 30 s than via ball milling for 5 min followed by hydration for 20 s.The attachment of cetyltrimethyl ammonium bromide and glycerol additives to the whisker tops promoted whisker growth.The whisker sponges exhibited good thermal barrier properties and compression cycle stability.展开更多
Heterostructured metals and alloys are a new class of materials in which mechanical behaviors between the heterogeneous regions are significantly different,and the mechanical properties of bulk materials are superior ...Heterostructured metals and alloys are a new class of materials in which mechanical behaviors between the heterogeneous regions are significantly different,and the mechanical properties of bulk materials are superior to the superposition of individual regions.In this paper,three distinct types of heterostructures were constructed in Mg-2.77Y(wt.%)alloy by applying simple thermomechanical processing.Namely,Type I:the non-recrystallized grains of several tens of microns were embedded in the micron-scaled recrystallized grains that were distributed along shear bands and dispersed near grain boundaries;Type II:the aggregations of micron-scaled recrystallized grains were surrounded by the non-recrystallized grains;Type II:the micron-scaled recrystallized grains dominated the microstructure,and the non-recrystallized regions with diameters of tens of micrometers were surrounded by those fine recrystallized grains.Mechanical tests showed that the material with type III heterostructure had the optimal combination of yield strength and uniform elongation.This is attributed to its remarkable hetero-deformation induced(HDI)strengthening and dislocation strengthening.At the initial stage of plastic deformation(engineering strain below 4%),the rapid accumulation of geometrically necessary dislocations(GNDs)at the interfaces between recrystallized and non-recrystallized regions and between neighboring recrystallized grains lead to the significant HDI strengthening.As deformation proceeded,the HDI strengthening effect gradually decreased,and the traditional dislocation strengthening that was caused by GNDs accumulation at grain boundaries became significant.In-situ electron back-scattered diffraction(EBSD)testing revealed that the non-basal slip in the non-recrystallized regions became more remarkable in the late stage of deformation,which improved ductility and strain hardening of the alloy.These findings provide new insight into the design of high-performance hexagonal close-packed structural materials by using the concept of HDI strengthening.展开更多
The jasmonate ZIM-domain(JAZ)family of proteins serves as co-receptors and transcriptional repressors of jasmonic acid(JA)in plants.Their functional diversity and multiple roles make them important components of the r...The jasmonate ZIM-domain(JAZ)family of proteins serves as co-receptors and transcriptional repressors of jasmonic acid(JA)in plants.Their functional diversity and multiple roles make them important components of the regulatory network of JA and other hormonal signaling pathways.In this review,we provide an overview of the latest findings on JAZ family proteins and emphasize their roles in plant growth and development,and response to biotic and abiotic stress,along with their underlying mechanisms.Moreover,existing challenges and future applications are outlined with the aim of offering a reference for further research on JAZ proteins in the context of plant physiology.展开更多
This study explores the utilization of various chemometric analytical methods for determining the quality of pressed sesame oil with different adulteration levels of refined sesame oil using UV spectral fingerprints.T...This study explores the utilization of various chemometric analytical methods for determining the quality of pressed sesame oil with different adulteration levels of refined sesame oil using UV spectral fingerprints.The goal of this study was to provide a reliable tool for assessing the quality of sesame oil.The UV spectra of 51 samples of pressed sesame oil and 420 adulterated samples with refined sesame oil were measured in the range of 200-330 nm.Various classification and prediction methods,including linear discrimination analysis(LDA),support vector machines(SVM),soft independent modeling of class analogy(SIMCA),partial least squares regression(PLSR),support vector machine regression(SVR),and back-propagation neural network(BPNN),were employed to analyze the UV spectral data of pressed sesame oil and adulterated sesame oil.The results indicated that SVM outperformed the other classification methods in qualitatively identifying adulterated sesame oil,achieving an accuracy of 96.15%,a sensitivity of 97.87%,and a specificity of 80%.For quantitative analysis,BPNN yielded the best prediction results,with an R^(2) value of 0.99,RMSEP of 2.34%,and RPD value of 10.60(LOD of 8.60%and LOQ of 28.67%).Overall,the developed models exhibited significant potential for rapidly identifying and predicting the quality of sesame oil.展开更多
Objective:This study aimed to explore the effects of our rational emotive behavior therapy(REBT)program on symptoms,anxiety,depression,and sleep state in patients with colorectal cancer(CRC)undergoing chemotherapy.Met...Objective:This study aimed to explore the effects of our rational emotive behavior therapy(REBT)program on symptoms,anxiety,depression,and sleep state in patients with colorectal cancer(CRC)undergoing chemotherapy.Methods:From October 2020 to May 2021,fifty-six patients with CRC in a hospital in the Hunan Province were randomly divided into an intervention group(n=28)and a control group(n=28).The patients in the intervention group completed a 6-week REBT program based on routine nursing care,including four courses:1)establish a relationship and formulate health files;2)group communications and study symptom management;3)continuously provide health knowledge and strengthen healthy behavior;and 4)review the treatment and summary.The control group maintained routine nursing care.The simplified Chinese version of the Memorial Symptom Assessment Scale Short Form(MSASeSFeSC),the Hospital Anxiety and Depression Scale(HADS),and the Pittsburgh Sleep Quality Index(PSQI)scale were used to investigate and compare the intervention effects of the two groups at baseline(T1,before the intervention),four weeks(T2),and six weeks(T3)after the intervention.Results:The intervention group was significantly improved in symptoms,anxiety,depression,and sleep state,compared with the control group.At T2,MSASeSFeSC(24.43±4.26 vs.28.07±3.91),symptom distress(17.29±4.04 vs.19.39±3.59),symptom frequency(7.14±1.51 vs.8.68±1.42),HADS(13.68±3.38 vs.15.86±3.79),anxiety(3.89±1.85 vs.5.18±2.18),and depression(9.79±2.06 vs.10.68±2.23),showed that the difference between the two groups was statistically significant(P<0.05).At T3,MSASeSFeSC(23.89±3.54 vs.30.14±3.94),symptom distress(17.61±3.52 vs.21.32±3.57),symptom frequency(6.29±1.49 vs.8.82±1.47),HADS(11.82±2.57 vs.16.29±3.13),anxiety(3.21±1.64 vs.5.61±1.77),and depression(8.61±1.52 vs.10.68±1.81),showed that the difference between the two groups was statistically significant(P<0.05).The sleep state of the intervention group was better than the control group at T3,with decreased score of PSQI[4.00(3.00,8.00)vs.9.00(7.00,12.50),Z=-3.706,P<0.001].Conclusion:The 6-week REBT program can effectively improve the symptom,anxiety,depression,and sleep state of patients with CRC undergoing chemotherapy,which could as a care plan for patients with CRC who are repeatedly admitted to the hospital for chemotherapy.展开更多
Sea surface wind(SSW)observations from a newly developed“Black Pearl”wave glider,the Chinese-French Oceanography Satellite(CFOSAT),the HY-2A microwave scatterometer,and a recently released high-resolution atmospheri...Sea surface wind(SSW)observations from a newly developed“Black Pearl”wave glider,the Chinese-French Oceanography Satellite(CFOSAT),the HY-2A microwave scatterometer,and a recently released high-resolution atmospheric reanalysis(ERA5)are evaluated with respect to in-situ buoy observations(115.46°E,19.85°N)from the South China Sea.Buoy observations from June to November 2019 are used to evaluate the wind estimates from the different platforms.The comparisons show that the HY-2A and CFOSAT scatterometer wind speeds have mean root mean square errors(RMSEs)of approximately 1.6 and 1.6 m/s,respectively,and the corresponding mean wind direction RMSEs are approximately 19°and 17°,which indicates that these satellite retrievals meet the requirements of design engineering missions.The wind speed and wind direction RMSEs of ERA5 are approximately 1.9 m/s and 33°,respectively.The correlation coefficients between the HY-2A,CFOSAT,and ERA5 wind speeds and the buoy observations are 0.86,0.85,and 0.84,respectively,and the corresponding coefficients of the wind direction are 0.98,0.98,and 0.93,respectively,at a 95%confidence level.However,the wind sensor in the wave glider provides relatively poor-quality observations compared with the buoy measurements and has higher wind speed and wind direction RMSEs of 2.9 m/s and 50.1°,respectively.Taylor diagrams are utilized to illustrate comprehensive wind comparisons between the multiplatform observations and buoy observations.The results help identify the basic biases in SSWs among different products and enhance confidence in the future use of SSW data for studies of upper ocean dynamics and climate analysis.Suggestions are also off ered to help improve the design of next-generation wave gliders.展开更多
With the development of the rail transit industry,more attention has been paid to the passive safety of rail vehicles.Structural damage is one of the main failure behaviors in a rail vehicle collision,but it has been ...With the development of the rail transit industry,more attention has been paid to the passive safety of rail vehicles.Structural damage is one of the main failure behaviors in a rail vehicle collision,but it has been paid little attention to in past research.In this paper,the quasi-static fracture experiments of SUS301L-MT under different stress states were carried out.The mechanical fracture properties of this material were studied,and the corresponding finite element simulation accuracy was improved to guide the design of vehicle crashworthiness.Through the tests,the fracture behavior of materials with wide stress triaxiality was obtained,and each specimen’s fracture locations and fracture strains were determined.Parameters of a generalized incremental stress state dependent damage model(GISSMO)of the material were calibrated,and the model’s accuracy was verified with test results from a 45°shear specimen.The GISSMO failure model accurately reflected the fracture characteristics of the material.The mesh dependency of this model was modified and discussed.The results show that the simulation agrees well with experimental data for the force-displacement curve after correction,but the strain distribution needs to be further studied and improved.展开更多
We should add the following acknowledge:Jing Teng thanks the support from the Youth Innovation Promotion Association Project,Chinese Academy of Sciences.
We report an experimental study of electron transport properties of MnSe/(Bi,Sb)_2Te_3 heterostructures,in which MnSe is an antiferromagnetic insulator,and(Bi,Sb)_2Te_3 is a three-dimensional topological insulator(TI)...We report an experimental study of electron transport properties of MnSe/(Bi,Sb)_2Te_3 heterostructures,in which MnSe is an antiferromagnetic insulator,and(Bi,Sb)_2Te_3 is a three-dimensional topological insulator(TI).Strong magnetic proximity effect is manifested in the measurements of the Hall effect and longitudinal resistances.Our analysis shows that the gate voltage can substantially modify the anomalous Hall conductance,which exceeds 0.1 e^(2)/h at temperature T=1.6 K and magnetic field μ_0H=5 T,even though only the top TI surface is in proximity to MnSe.This work suggests that heterostructures based on antiferromagnetic insulators provide a promising platform for investigating a wide range of topological spintronic phenomena.展开更多
Measurement of residual stress is significant to ensure safety, reliability and the life of composites, and currently has been a hot issue in scientific research. The fabrication processes such as ...Measurement of residual stress is significant to ensure safety, reliability and the life of composites, and currently has been a hot issue in scientific research. The fabrication processes such as machining, and heat treatment inherit either kind of residual stress which had either positive consequences or negative ones, for example, the fatigue limit of a component enhances by compressive stress, whereas corrosion resistance gets reduced by tensile stress. This study is aimed at a brief overview of the recent advancement in this field to help researchers in the in-depth study of measuring residual stress. It helps them in selecting the most appropriate techniques among destructive methods i.e., mainly Contour, ring core, deep hole-drilling method, and non-destructive techniques i.e., diffraction, ultrasonic method, depending on their requirements and applications. For each available technique, working methodology, physical limitations, and applications are discussed. At the end of this paper, future trends regarding an assessment of residual stress have been forecasted.展开更多
With the rapid development of interest rate market and big data,the banking industry has shown the obvious phenomenon of“two or eight law”,20%of the high quality customers occupy most of the bank’s assets,how to pr...With the rapid development of interest rate market and big data,the banking industry has shown the obvious phenomenon of“two or eight law”,20%of the high quality customers occupy most of the bank’s assets,how to prevent the loss of bank credit card customers has become a growing concern for banks.Therefore,it is particularly important to establish a customer churn early warning model.In this paper,we will use the random forest method to establish a customer churn early warning model,focusing on the churn of bank credit card customers and predicting the possibility of future churn of customers.Due to the large data size of banks,the complexity of their customer base,and the diversity of user characteristics,it is not easy for banks to accurately predict churned customers,and there are few customer churn early warning studies suitable for banks.Compared with the traditional bank credit risk prediction algorithm,this method is proved to be useful in the early stage of churn warning,and has the advantages of high prediction accuracy,large amount of processed data,and good model interpretability,which can help to retain valuable customers in advance and thus achieve the purpose of reducing cost and increasing efficiency.展开更多
For the traditional multi-process capability construction method based on principal component analysis,the process variables are mainly considered,but not the process capability,which leads to the deviation of the con...For the traditional multi-process capability construction method based on principal component analysis,the process variables are mainly considered,but not the process capability,which leads to the deviation of the contribution rate of principal component.In response to the question,this paper first clarifies the problem from two aspects:theoretical analysis and example proof.Secondly,aiming at the rationality of principal components degree,an evaluation method for pre-processing data before constructing MPCI using PCA is proposed.The pre-processing of data is mainly to standardize the specification interval of quality characteristics making the principal components degree more reasonable and optimizes the process capability evaluation method.Finally,the effectiveness and feasibility of the method are proved by an application example.展开更多
Amniotes differ substantially in absolute and relative brain size after controlling for allometry,and numerous hypotheses have been proposed to explain brain size evolution.Brain size is thought to correlate with proc...Amniotes differ substantially in absolute and relative brain size after controlling for allometry,and numerous hypotheses have been proposed to explain brain size evolution.Brain size is thought to correlate with processing capacity and the brain’s ability to support complex manipulation such as nest-building skills.The increased complexity of nest structure is supposed to be a measure of an ability to manipulate nesting material into the required shape.The degree of nest-structure complexity is also supposed to be associated with body mass,partly because small species lose heat faster and delicate and insulated nests are more crucial for temperature control of eggs during incubation by small birds.Here,we conducted comparative analyses to test these hypotheses by investigating whether the complexity of species-typical nest structure can be explained by brain size and body mass(a covariate also to control for allometric effects on brain size)across 1353 bird species from 147 families.Consistent with these hypotheses,our results revealed that avian brain size increases as the complexity of the nest structure increases after controlling for a significant effect of body size,and also that a negative relationship exists between nest complexity and body mass.展开更多
Chimeric antigen receptor(CAR)-T cell therapy has achieved remarkable success in the treatment of hematological malignancies.Based on the immunomodulatory capability of CAR-T cells,efforts have turned toward exploring...Chimeric antigen receptor(CAR)-T cell therapy has achieved remarkable success in the treatment of hematological malignancies.Based on the immunomodulatory capability of CAR-T cells,efforts have turned toward exploring their potential in treating autoimmune diseases.Bibliometric analysis of 210 records from 128 academic journals published by 372 institutions in 40 countries/regions indicates a growing number of publications on CAR-T therapy for autoimmune diseases,covering a range of subtypes such as systemic lupus erythematosus,multiple sclerosis,among others.CAR-T therapy holds promise in mitigating several shortcomings,including the indiscriminate suppression of the immune system by traditional immunosuppressants,and non-sustaining therapeutic levels of monoclonal antibodies due to inherent pharmacokinetic constraints.By persisting and proliferating in vivo,CAR-T cells can offer a tailored and precise therapeutics.This paper reviewed preclinical experiments and clinical trials involving CAR-T and CAR-related therapies in various autoimmune diseases,incorporating innovations well-studied in the field of hematological tumors,aiming to explore a safe and effective therapeutic option for relapsed/refractory autoimmune diseases.展开更多
Block copolymers(BCPs) with high Flory-Huggins parameter(χ) and balanced surface energy have aroused tremendous interest for ultra-small nanopatterns processing.However,high χ and balanced surface energy are general...Block copolymers(BCPs) with high Flory-Huggins parameter(χ) and balanced surface energy have aroused tremendous interest for ultra-small nanopatterns processing.However,high χ and balanced surface energy are generally contradicted.The fine tune of chain structure might be a useful way to achieve high χ and balanced surface energy.To realize this,the block copolymer with exactly uniform chain structure,i.e.,defined molecular structure,is highly desirable for accurately evaluating the phase behavior.Herein,two kinds of discrete oligo ester-b-oligo olefin block copolymers with different chemical structures(oligo lactic acid-boligo olefin BCP,oLA_(n)-b-C_(m);oligo phenyl lactic acid-b-oligo olefin BCP,oPL_(n)-b-C_(m)) were modularly synthesized through iterative growth methods.The effect of chain structure on segregation strength and surface properties was quantitatively investigated using the discrete BCPs as precise models.On the one hand,introducing rigid and nonpolar phenyl groups into oligo ester block has a negligible effect on the chemical incompatibility,as confirmed by the identical high χ values of oLA_(n)-b-C_(m) and oPL_(n)-b-C_(m)(χ_(oLA/C)=0.21 and χ_(oPL/C)=0.19).On the other hand,the incorporation of nonpolar phenyl groups creates balanced surface energy,that is,the high χ and balanced surface energy were simultaneously achieved by oPL_(n)-b-C_(m).Therefore,sub-10 nm perpendicular nanopatterns can be easily produced upon brief thermal treatment,demonstrating its potential application in semiconductor manufacturing with ultra-small feature size.The discrete BCP can serve as a quantitative and exquisite model to study the critical contribution of chain structures on phase separation behavior,providing insightful understanding to facilitate the potential application in the chip process.展开更多
Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for cancer.However,serious toxic side effects caused by long-term drug accumulation can cause significant ...Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for cancer.However,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor drugs.In this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is reduced.The unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe complex.In addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor environment.The change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic effect.In vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in tumors.This work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.展开更多
Metals and alloys with heterogeneous microstructures are an emerging class of materials that exhibit exceptional mechanical properties,owing to the novel scientific principle of hetero-deformation induced(HDI)strength...Metals and alloys with heterogeneous microstructures are an emerging class of materials that exhibit exceptional mechanical properties,owing to the novel scientific principle of hetero-deformation induced(HDI)strengthening and hardening.For magnesium alloys,due to their low recrystallization temperature,poor ductility at room temperature,limited cold workability,and the tendency to generate strong basal texture during deformation,it is difficult to obtain heterostructures without relying on precipitation of the second phases.Here,three heterostructured Mg-2.9Y(wt.%)materials with varying accumulative equivalent true strains,i.e.,5%-5 cycles,7.5%-5 cycles,and 10%-5 cycles materials were fabricated via applying five complete triaxial compression cycles to the bulk alloy.The 5%-5 cycles material with an accumulative equivalent true strain of 0.37 is featured with long twin lamellae embedded in coarse grains.When the accumulative true strain increases to 0.72,a heterogeneous structure composed of long and short twin lamellae is formed inside the 7.5%-5 cycles material.As the equivalent true strain further increases to 1.01,the 10%-5 cycles material exhibits a mixed structure with densely refined twin lamellae embedded in the coarse-grained matrix.The room-temperature uniaxial tensile tests show that the yield strength of the materials processed by triaxial cyclic compression(TCC)has been significantly improved compared to that at the initial state,whereas ductility was not significantly sacrificed without the subsequent heat treatment.The dense and refined twin lamellae that serve as hard domains in this material provide a high density of interfaces and impede dislocation motion effectively.This results in significant HDI strengthening and hardening.These findings provide new insight into the design of heterostructured hexagonal close-packed materials with both high strength and good ductility.展开更多
基金supported by the National Natural Science Foundation of China(32061123008).
文摘Unstable environments intensify the frequency of extreme disasters.Long-term climate changes can lead to agricultural and ecological degradation that threatens population sustainability.To better understand past climatic events and consequences,here we present a reconstruction of the self-calibrating Palmer drought severity index(scPDSI)from September to August for the desert margins of northern China,dating back to 1742.The reconstruction accounts for 42.9%of the variation of meteorological data between 1951 and 2020.Our spatial correlation analyses showed significant correlations between scPDSI,runoff,and precipitation.Over the past 279 years,the study area has undergone nine dry and eight wet periods,with the most severe climate extremes between the 1850s and 1890s.This period of prolonged drought in northeastern China coincided with the combined impacts of climatic factors and human influences,contributing to the fall of the Qing Dynasty.Analysis of periodicity and anomalies in sea surface temperatures indicate a strong association between wet and dry cycles and El Niño-Southern Oscillations.Our findings offer insights into long-term dry and wet fluctuations at the desert margins in northern China and elucidate the relationship between drought and the dynamics of civilizations.They also highlight the potential impact of extremes in climate on modern society,especially under the four projected shared socioeconomic pathways climatic scenarios,which predict worsening droughts in northern China.
基金supported by the National Key R&D Program of China(2022YFA1304204)National Natural Science Foundation of China(31772579).
文摘Background Sex hormones play important roles in the estrus return of post-weaning sows.Previous studies have demonstrated a complex and bi-directional regulation between sex hormones and gut microbiota.However,the extent to which the gut microbiota affects estrus return of post-weaning sows is largely unknown.Results In this study,we first screened 207 fecal samples from well-phenotyped sows by 16S rRNA gene sequencing and identified significant associations between microbes and estrus return of post-weaning sows.Using metagenomic sequencing data from 85 fecal samples,we identified 37 bacterial species that were significantly associated with estrus return.Normally returning sows were characterized by increased abundances of L.reuteri and P.copri and decreased abundances of B.fragilis,S.suis,and B.pseudolongum.The changes in gut microbial composition significantly altered the functional capacity of steroid hormone biosynthesis in the gut microbiome.The results were confirmed in a validation cohort.Significant changes in sex steroid hormones and related compounds were found between normal and non-return sows via metabolome analysis.An integrated analysis of differential bacterial species,metagenome,and fecal metabolome provided evidence that normal return-associated bacterial species L.reuteri and Prevotella spp.participated in the degradation of pregnenolone,progesterone,and testosterone,thereby promoting estrogen biosynthesis.Furthermore,the microbial metabolites related to sow energy and nutrient supply or metabolic disorders also showed relationships with sow estrus return.Conclusions An integrated analysis of differentially abundant bacterial species,metagenome,and fecal metabolome revealed the involvement of L.reuteri and Prevotella spp.in sow estrus return.These findings provide deep insight into the role of gut microbiota in the estrus return of post-weaning sows and the complex cross-talk between gut microbiota and sex hormones,suggesting that the manipulation of the gut microbiota could be an effective strategy to improve sow estrus return after weaning.
基金supported by the Degradable Plastics Engineering Research Center of Yunnan Provincial Education Department(KKPU202205001).
文摘Elucidating the effect of growth periods on the quality of calcium sulfate whiskers(CSWs)prepared from calcium sulfate dihydrate(DH)is imperative.Herein,crystal seeds and whiskers were prepared from DH in a water–glycerol system.Longer whiskers were obtained from crystal seeds prepared via hydration of DH for 30 s than via ball milling for 5 min followed by hydration for 20 s.The attachment of cetyltrimethyl ammonium bromide and glycerol additives to the whisker tops promoted whisker growth.The whisker sponges exhibited good thermal barrier properties and compression cycle stability.
基金funding from the National Natural Science Foundation of China(No.51922026)the Fundamental Research Funds for the Central Universities(Nos.N2002005,N2007011)the 111 Project(No.B20029).
文摘Heterostructured metals and alloys are a new class of materials in which mechanical behaviors between the heterogeneous regions are significantly different,and the mechanical properties of bulk materials are superior to the superposition of individual regions.In this paper,three distinct types of heterostructures were constructed in Mg-2.77Y(wt.%)alloy by applying simple thermomechanical processing.Namely,Type I:the non-recrystallized grains of several tens of microns were embedded in the micron-scaled recrystallized grains that were distributed along shear bands and dispersed near grain boundaries;Type II:the aggregations of micron-scaled recrystallized grains were surrounded by the non-recrystallized grains;Type II:the micron-scaled recrystallized grains dominated the microstructure,and the non-recrystallized regions with diameters of tens of micrometers were surrounded by those fine recrystallized grains.Mechanical tests showed that the material with type III heterostructure had the optimal combination of yield strength and uniform elongation.This is attributed to its remarkable hetero-deformation induced(HDI)strengthening and dislocation strengthening.At the initial stage of plastic deformation(engineering strain below 4%),the rapid accumulation of geometrically necessary dislocations(GNDs)at the interfaces between recrystallized and non-recrystallized regions and between neighboring recrystallized grains lead to the significant HDI strengthening.As deformation proceeded,the HDI strengthening effect gradually decreased,and the traditional dislocation strengthening that was caused by GNDs accumulation at grain boundaries became significant.In-situ electron back-scattered diffraction(EBSD)testing revealed that the non-basal slip in the non-recrystallized regions became more remarkable in the late stage of deformation,which improved ductility and strain hardening of the alloy.These findings provide new insight into the design of high-performance hexagonal close-packed structural materials by using the concept of HDI strengthening.
基金funded by the National Natural Science Foundation of China (32372156,32201838,32272157)the Natural Science Foundation of Guangdong Province (2024A1515011084,2023A1515012052,2023A1515012092)the Science and Technology Project of Guangzhou (2023A04J0749,2023A04J1452).
文摘The jasmonate ZIM-domain(JAZ)family of proteins serves as co-receptors and transcriptional repressors of jasmonic acid(JA)in plants.Their functional diversity and multiple roles make them important components of the regulatory network of JA and other hormonal signaling pathways.In this review,we provide an overview of the latest findings on JAZ family proteins and emphasize their roles in plant growth and development,and response to biotic and abiotic stress,along with their underlying mechanisms.Moreover,existing challenges and future applications are outlined with the aim of offering a reference for further research on JAZ proteins in the context of plant physiology.
基金supported by the project number of“China Agricultural Research System funded by the Ministry of Agriculture”CARS-14,the Key Project of Science and Technology of Henan Province (201300110600)the“Double First-Class”Project for Postgraduate Academic Innovation Enhancement Programme of Henan University of Technology (HAUTSYL2023TS16)Education and Teaching Reform Research and Practice Project in School of International Education,Henan University of Technology (GJXY202407).
文摘This study explores the utilization of various chemometric analytical methods for determining the quality of pressed sesame oil with different adulteration levels of refined sesame oil using UV spectral fingerprints.The goal of this study was to provide a reliable tool for assessing the quality of sesame oil.The UV spectra of 51 samples of pressed sesame oil and 420 adulterated samples with refined sesame oil were measured in the range of 200-330 nm.Various classification and prediction methods,including linear discrimination analysis(LDA),support vector machines(SVM),soft independent modeling of class analogy(SIMCA),partial least squares regression(PLSR),support vector machine regression(SVR),and back-propagation neural network(BPNN),were employed to analyze the UV spectral data of pressed sesame oil and adulterated sesame oil.The results indicated that SVM outperformed the other classification methods in qualitatively identifying adulterated sesame oil,achieving an accuracy of 96.15%,a sensitivity of 97.87%,and a specificity of 80%.For quantitative analysis,BPNN yielded the best prediction results,with an R^(2) value of 0.99,RMSEP of 2.34%,and RPD value of 10.60(LOD of 8.60%and LOQ of 28.67%).Overall,the developed models exhibited significant potential for rapidly identifying and predicting the quality of sesame oil.
基金support from the Education Department of Hunan Province(No.19A419).
文摘Objective:This study aimed to explore the effects of our rational emotive behavior therapy(REBT)program on symptoms,anxiety,depression,and sleep state in patients with colorectal cancer(CRC)undergoing chemotherapy.Methods:From October 2020 to May 2021,fifty-six patients with CRC in a hospital in the Hunan Province were randomly divided into an intervention group(n=28)and a control group(n=28).The patients in the intervention group completed a 6-week REBT program based on routine nursing care,including four courses:1)establish a relationship and formulate health files;2)group communications and study symptom management;3)continuously provide health knowledge and strengthen healthy behavior;and 4)review the treatment and summary.The control group maintained routine nursing care.The simplified Chinese version of the Memorial Symptom Assessment Scale Short Form(MSASeSFeSC),the Hospital Anxiety and Depression Scale(HADS),and the Pittsburgh Sleep Quality Index(PSQI)scale were used to investigate and compare the intervention effects of the two groups at baseline(T1,before the intervention),four weeks(T2),and six weeks(T3)after the intervention.Results:The intervention group was significantly improved in symptoms,anxiety,depression,and sleep state,compared with the control group.At T2,MSASeSFeSC(24.43±4.26 vs.28.07±3.91),symptom distress(17.29±4.04 vs.19.39±3.59),symptom frequency(7.14±1.51 vs.8.68±1.42),HADS(13.68±3.38 vs.15.86±3.79),anxiety(3.89±1.85 vs.5.18±2.18),and depression(9.79±2.06 vs.10.68±2.23),showed that the difference between the two groups was statistically significant(P<0.05).At T3,MSASeSFeSC(23.89±3.54 vs.30.14±3.94),symptom distress(17.61±3.52 vs.21.32±3.57),symptom frequency(6.29±1.49 vs.8.82±1.47),HADS(11.82±2.57 vs.16.29±3.13),anxiety(3.21±1.64 vs.5.61±1.77),and depression(8.61±1.52 vs.10.68±1.81),showed that the difference between the two groups was statistically significant(P<0.05).The sleep state of the intervention group was better than the control group at T3,with decreased score of PSQI[4.00(3.00,8.00)vs.9.00(7.00,12.50),Z=-3.706,P<0.001].Conclusion:The 6-week REBT program can effectively improve the symptom,anxiety,depression,and sleep state of patients with CRC undergoing chemotherapy,which could as a care plan for patients with CRC who are repeatedly admitted to the hospital for chemotherapy.
基金Supported by the National Natural Science Foundation of China(No.42076016)the Fundamental Research Funds for the Central Universities(No.2019B02814)the National Key Research and Development Program of China(No.2018YFC0213104)。
文摘Sea surface wind(SSW)observations from a newly developed“Black Pearl”wave glider,the Chinese-French Oceanography Satellite(CFOSAT),the HY-2A microwave scatterometer,and a recently released high-resolution atmospheric reanalysis(ERA5)are evaluated with respect to in-situ buoy observations(115.46°E,19.85°N)from the South China Sea.Buoy observations from June to November 2019 are used to evaluate the wind estimates from the different platforms.The comparisons show that the HY-2A and CFOSAT scatterometer wind speeds have mean root mean square errors(RMSEs)of approximately 1.6 and 1.6 m/s,respectively,and the corresponding mean wind direction RMSEs are approximately 19°and 17°,which indicates that these satellite retrievals meet the requirements of design engineering missions.The wind speed and wind direction RMSEs of ERA5 are approximately 1.9 m/s and 33°,respectively.The correlation coefficients between the HY-2A,CFOSAT,and ERA5 wind speeds and the buoy observations are 0.86,0.85,and 0.84,respectively,and the corresponding coefficients of the wind direction are 0.98,0.98,and 0.93,respectively,at a 95%confidence level.However,the wind sensor in the wave glider provides relatively poor-quality observations compared with the buoy measurements and has higher wind speed and wind direction RMSEs of 2.9 m/s and 50.1°,respectively.Taylor diagrams are utilized to illustrate comprehensive wind comparisons between the multiplatform observations and buoy observations.The results help identify the basic biases in SSWs among different products and enhance confidence in the future use of SSW data for studies of upper ocean dynamics and climate analysis.Suggestions are also off ered to help improve the design of next-generation wave gliders.
基金National Natural Scienceof China(Grant No.52172409)Sichuan Provincial Outstanding Youth Fund of China(Grant No.2022JDJQ0025)。
文摘With the development of the rail transit industry,more attention has been paid to the passive safety of rail vehicles.Structural damage is one of the main failure behaviors in a rail vehicle collision,but it has been paid little attention to in past research.In this paper,the quasi-static fracture experiments of SUS301L-MT under different stress states were carried out.The mechanical fracture properties of this material were studied,and the corresponding finite element simulation accuracy was improved to guide the design of vehicle crashworthiness.Through the tests,the fracture behavior of materials with wide stress triaxiality was obtained,and each specimen’s fracture locations and fracture strains were determined.Parameters of a generalized incremental stress state dependent damage model(GISSMO)of the material were calibrated,and the model’s accuracy was verified with test results from a 45°shear specimen.The GISSMO failure model accurately reflected the fracture characteristics of the material.The mesh dependency of this model was modified and discussed.The results show that the simulation agrees well with experimental data for the force-displacement curve after correction,but the strain distribution needs to be further studied and improved.
文摘We should add the following acknowledge:Jing Teng thanks the support from the Youth Innovation Promotion Association Project,Chinese Academy of Sciences.
基金Supported by the National Key Research and Development Program of China (Grant No.2016YFA0300600)the National Natural Science Foundation of China (Grant No.11961141011)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000)。
文摘We report an experimental study of electron transport properties of MnSe/(Bi,Sb)_2Te_3 heterostructures,in which MnSe is an antiferromagnetic insulator,and(Bi,Sb)_2Te_3 is a three-dimensional topological insulator(TI).Strong magnetic proximity effect is manifested in the measurements of the Hall effect and longitudinal resistances.Our analysis shows that the gate voltage can substantially modify the anomalous Hall conductance,which exceeds 0.1 e^(2)/h at temperature T=1.6 K and magnetic field μ_0H=5 T,even though only the top TI surface is in proximity to MnSe.This work suggests that heterostructures based on antiferromagnetic insulators provide a promising platform for investigating a wide range of topological spintronic phenomena.
文摘Measurement of residual stress is significant to ensure safety, reliability and the life of composites, and currently has been a hot issue in scientific research. The fabrication processes such as machining, and heat treatment inherit either kind of residual stress which had either positive consequences or negative ones, for example, the fatigue limit of a component enhances by compressive stress, whereas corrosion resistance gets reduced by tensile stress. This study is aimed at a brief overview of the recent advancement in this field to help researchers in the in-depth study of measuring residual stress. It helps them in selecting the most appropriate techniques among destructive methods i.e., mainly Contour, ring core, deep hole-drilling method, and non-destructive techniques i.e., diffraction, ultrasonic method, depending on their requirements and applications. For each available technique, working methodology, physical limitations, and applications are discussed. At the end of this paper, future trends regarding an assessment of residual stress have been forecasted.
基金This work was supported by the National Natural Science Foundation of China(No.72073041)Open Foundation for the University Innovation Platform in Hunan Province(No.18K103)+2 种基金2011 Collaborative Innovation Center for Development and Utilization of Finance and Economics Big Data Property,Universities of Hunan Province,Open Project(Nos.20181901CRP03,20181901CRP04,20181901CRP05)2020 Hunan Provincial Higher Education Teaching Reform Research Project(Nos.HNJG-2020-1130,HNJG-2020-1124)2020 General Project of Hunan Social Science Fund(No.20B16).
文摘With the rapid development of interest rate market and big data,the banking industry has shown the obvious phenomenon of“two or eight law”,20%of the high quality customers occupy most of the bank’s assets,how to prevent the loss of bank credit card customers has become a growing concern for banks.Therefore,it is particularly important to establish a customer churn early warning model.In this paper,we will use the random forest method to establish a customer churn early warning model,focusing on the churn of bank credit card customers and predicting the possibility of future churn of customers.Due to the large data size of banks,the complexity of their customer base,and the diversity of user characteristics,it is not easy for banks to accurately predict churned customers,and there are few customer churn early warning studies suitable for banks.Compared with the traditional bank credit risk prediction algorithm,this method is proved to be useful in the early stage of churn warning,and has the advantages of high prediction accuracy,large amount of processed data,and good model interpretability,which can help to retain valuable customers in advance and thus achieve the purpose of reducing cost and increasing efficiency.
文摘For the traditional multi-process capability construction method based on principal component analysis,the process variables are mainly considered,but not the process capability,which leads to the deviation of the contribution rate of principal component.In response to the question,this paper first clarifies the problem from two aspects:theoretical analysis and example proof.Secondly,aiming at the rationality of principal components degree,an evaluation method for pre-processing data before constructing MPCI using PCA is proposed.The pre-processing of data is mainly to standardize the specification interval of quality characteristics making the principal components degree more reasonable and optimizes the process capability evaluation method.Finally,the effectiveness and feasibility of the method are proved by an application example.
基金Financial support was provided by the National Natural Science Foundation of China(Grants 32211530420 and 32170481).
文摘Amniotes differ substantially in absolute and relative brain size after controlling for allometry,and numerous hypotheses have been proposed to explain brain size evolution.Brain size is thought to correlate with processing capacity and the brain’s ability to support complex manipulation such as nest-building skills.The increased complexity of nest structure is supposed to be a measure of an ability to manipulate nesting material into the required shape.The degree of nest-structure complexity is also supposed to be associated with body mass,partly because small species lose heat faster and delicate and insulated nests are more crucial for temperature control of eggs during incubation by small birds.Here,we conducted comparative analyses to test these hypotheses by investigating whether the complexity of species-typical nest structure can be explained by brain size and body mass(a covariate also to control for allometric effects on brain size)across 1353 bird species from 147 families.Consistent with these hypotheses,our results revealed that avian brain size increases as the complexity of the nest structure increases after controlling for a significant effect of body size,and also that a negative relationship exists between nest complexity and body mass.
基金Ministry of Science and Technology China Brain Initiative Grant STI2030-Major Projects(No.2022ZD0204700)National Natural Science Foundation of China(Nos.82371404,82271341,82071380,and 81873743)Knowledge Innovation Program of Wuhan Shuguang Project(No.2022020801020454)
文摘Chimeric antigen receptor(CAR)-T cell therapy has achieved remarkable success in the treatment of hematological malignancies.Based on the immunomodulatory capability of CAR-T cells,efforts have turned toward exploring their potential in treating autoimmune diseases.Bibliometric analysis of 210 records from 128 academic journals published by 372 institutions in 40 countries/regions indicates a growing number of publications on CAR-T therapy for autoimmune diseases,covering a range of subtypes such as systemic lupus erythematosus,multiple sclerosis,among others.CAR-T therapy holds promise in mitigating several shortcomings,including the indiscriminate suppression of the immune system by traditional immunosuppressants,and non-sustaining therapeutic levels of monoclonal antibodies due to inherent pharmacokinetic constraints.By persisting and proliferating in vivo,CAR-T cells can offer a tailored and precise therapeutics.This paper reviewed preclinical experiments and clinical trials involving CAR-T and CAR-related therapies in various autoimmune diseases,incorporating innovations well-studied in the field of hematological tumors,aiming to explore a safe and effective therapeutic option for relapsed/refractory autoimmune diseases.
基金supported by the National Natural Science Foundation of China(21925107,22273026)China Postdoctoral Science Foundation(71st,2022M712306)+1 种基金the Collaborative Innovation Center of Suzhou Nano Science and Technologythe Jiangsu Funding Program for Excellent Postdoctoral Talent。
文摘Block copolymers(BCPs) with high Flory-Huggins parameter(χ) and balanced surface energy have aroused tremendous interest for ultra-small nanopatterns processing.However,high χ and balanced surface energy are generally contradicted.The fine tune of chain structure might be a useful way to achieve high χ and balanced surface energy.To realize this,the block copolymer with exactly uniform chain structure,i.e.,defined molecular structure,is highly desirable for accurately evaluating the phase behavior.Herein,two kinds of discrete oligo ester-b-oligo olefin block copolymers with different chemical structures(oligo lactic acid-boligo olefin BCP,oLA_(n)-b-C_(m);oligo phenyl lactic acid-b-oligo olefin BCP,oPL_(n)-b-C_(m)) were modularly synthesized through iterative growth methods.The effect of chain structure on segregation strength and surface properties was quantitatively investigated using the discrete BCPs as precise models.On the one hand,introducing rigid and nonpolar phenyl groups into oligo ester block has a negligible effect on the chemical incompatibility,as confirmed by the identical high χ values of oLA_(n)-b-C_(m) and oPL_(n)-b-C_(m)(χ_(oLA/C)=0.21 and χ_(oPL/C)=0.19).On the other hand,the incorporation of nonpolar phenyl groups creates balanced surface energy,that is,the high χ and balanced surface energy were simultaneously achieved by oPL_(n)-b-C_(m).Therefore,sub-10 nm perpendicular nanopatterns can be easily produced upon brief thermal treatment,demonstrating its potential application in semiconductor manufacturing with ultra-small feature size.The discrete BCP can serve as a quantitative and exquisite model to study the critical contribution of chain structures on phase separation behavior,providing insightful understanding to facilitate the potential application in the chip process.
基金Project supported by the National Natural Science Foundation of China(92159103)Beijing Municipal Education Commission Outstanding Young Individual Project(CIT&TCD201904082)+1 种基金Youth High-level Talent Project of Capital Normal University(20530810024)Yanjing Young Scholar Program of Capital Normal University。
文摘Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for cancer.However,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor drugs.In this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is reduced.The unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe complex.In addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor environment.The change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic effect.In vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in tumors.This work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.
基金fundings supported by the National Key Research and Development Program of China(No.2021YFA1200203)the National Natural Science Foundation of China(Nos.52371097,52301136,51922026,and 52071068)。
文摘Metals and alloys with heterogeneous microstructures are an emerging class of materials that exhibit exceptional mechanical properties,owing to the novel scientific principle of hetero-deformation induced(HDI)strengthening and hardening.For magnesium alloys,due to their low recrystallization temperature,poor ductility at room temperature,limited cold workability,and the tendency to generate strong basal texture during deformation,it is difficult to obtain heterostructures without relying on precipitation of the second phases.Here,three heterostructured Mg-2.9Y(wt.%)materials with varying accumulative equivalent true strains,i.e.,5%-5 cycles,7.5%-5 cycles,and 10%-5 cycles materials were fabricated via applying five complete triaxial compression cycles to the bulk alloy.The 5%-5 cycles material with an accumulative equivalent true strain of 0.37 is featured with long twin lamellae embedded in coarse grains.When the accumulative true strain increases to 0.72,a heterogeneous structure composed of long and short twin lamellae is formed inside the 7.5%-5 cycles material.As the equivalent true strain further increases to 1.01,the 10%-5 cycles material exhibits a mixed structure with densely refined twin lamellae embedded in the coarse-grained matrix.The room-temperature uniaxial tensile tests show that the yield strength of the materials processed by triaxial cyclic compression(TCC)has been significantly improved compared to that at the initial state,whereas ductility was not significantly sacrificed without the subsequent heat treatment.The dense and refined twin lamellae that serve as hard domains in this material provide a high density of interfaces and impede dislocation motion effectively.This results in significant HDI strengthening and hardening.These findings provide new insight into the design of heterostructured hexagonal close-packed materials with both high strength and good ductility.
