With the presence of wind waves, the swaying of survey vessel may effect the quality of sub-bottom profiler records and, therefore, it is necessary to correct the distortions induced by wave action. A major issue is t...With the presence of wind waves, the swaying of survey vessel may effect the quality of sub-bottom profiler records and, therefore, it is necessary to correct the distortions induced by wave action. A major issue is to distinguish wind wave effect and real bedforms such as sand waves. In this paper, a bandstop filter is designed according to the frequency features of wind wave effect to treat the distortion of seabed topography by wind waves. The technique is used to correct the sub-bottom profile in order to eliminate the wave-induced distortions for the sub-bottom profile records from the Yangtze Estuary. This study shows that the undulate seabed record is resulted from wave action, rather than the presence of sand waves, and the filtration technique helps to eliminate the wave effect and recover the real morphology of seabed and the sediment sequence underneath. In addition, a method for data processing is proposed for the case that the record indeed represents a combination of wave effects and real bedforms.展开更多
Adaptive optics systems are the most powerful tools to counteract the image blurring caused by atmospheric turbulence,allowing ground-based telescopes to capture high-resolution images.A critical parameter influencing...Adaptive optics systems are the most powerful tools to counteract the image blurring caused by atmospheric turbulence,allowing ground-based telescopes to capture high-resolution images.A critical parameter influencing adaptive optics system performance is the atmospheric refractive index structure constant,C_(n)^(2),which characterizes the intensity of atmospheric optical turbulence as a function of altitude.Given its simplicity,the lunar scintillometer is the preferred method for detecting atmospheric turbulence in challenging environments like Dome A in Antarctica,where sites are still in the developmental stages and local environmental conditions are extremely harsh.However,optimizing the performance of such instruments requires carefully determining the baseline configuration of photon sensors according to each site's specific optical turbulence profile characteristics.This study uses a Monte Carlo method to identify the optimal configuration for the KunLun Turbulence Profiler(KLTP),an instrument comparable to the lunar scintillometer,developed for use at Dome A.Simulations conducted using the obtained optimal baseline configuration recovered three different model optical turbulence profiles,demonstrating the effectiveness of our method in obtaining an optimal baseline configuration.Our approach can be easily applied to baseline design for similar turbulence profilers at other sites.展开更多
Objective:Triple-negative breast cancer(TNBC)is a highly aggressive subtype that lacks targeted therapies,leading to a poorer prognosis.However,some patients achieve long-term recurrence-free survival(RFS),offering va...Objective:Triple-negative breast cancer(TNBC)is a highly aggressive subtype that lacks targeted therapies,leading to a poorer prognosis.However,some patients achieve long-term recurrence-free survival(RFS),offering valuable insights into tumor biology and potential treatment strategies.Methods:We conducted a comprehensive multi-omics analysis of 132 patients with American Joint Committee on Cancer(AJCC)stage III TNBC,comprising 36 long-term survivors(RFS≥8 years),62 moderate-term survivors(RFS:3-8 years),and 34 short-term survivors(RFS<3 years).Analyses investigated clinicopathological factors,whole-exome sequencing,germline mutations,copy number alterations(CNAs),RNA sequences,and metabolomic profiles.Results:Long-term survivors exhibited fewer metastatic regional lymph nodes,along with tumors showing reduced stromal fibrosis and lower Ki67 index.Molecularly,these tumors exhibited multiple alterations in genes related to homologous recombination repair,with higher frequencies of germline mutations and somatic CNAs.Additionally,tumors from long-term survivors demonstrated significant downregulation of the RTK-RAS signaling pathway.Metabolomic profiling revealed decreased levels of lipids and carbohydrate,particularly those involved in glycerophospholipid,fructose,and mannose metabolism,in long-term survival group.Multivariate Cox analysis identified fibrosis[hazard ratio(HR):12.70,95%confidence interval(95%CI):2.19-73.54,P=0.005]and RAC1copy number loss/deletion(HR:0.22,95%CI:0.06-0.83,P=0.026)as independent predictors of RFS.Higher fructose/mannose metabolism was associated with worse overall survival(HR:1.30,95%CI:1.01-1.68,P=0.045).Our findings emphasize the association between biological determinants and prolonged survival in patients with TNBC.Conclusions:Our study systematically identified the key molecular and metabolic features associated with prolonged survival in AJCC stage III TNBC,suggesting potential therapeutic targets to improve patient outcomes.展开更多
The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficien...The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficiency and low-cost manufacturing of the component.Blank design is the key part of plastic forming process design.For spinning-rolling process,the shape and size of the blank play a crucial role in process stability,deformation behavior and dimensional accuracy.So this work proposes a blank design method to determine the geometry structure and sizes of the blank.The mathematical model for calculating the blank size has been deduced based on volume conservation and neutral layer length invariance principle.The FE simulation and corresponding trial production of an actual big-tapered profiled ring disk show that the proposed blank design method is applicative.In order to obtain a preferred blank,the influence rules of blank size determined by different deformation degrees(rolling ratio k)on the spinning-rolling process are revealed by comprehensive FE simulations.Overall considering the process stability,circularity of the deformed ring disk and forming forces,a reasonable range of deformation degree(rolling ratio k)is recommended for the blank design of the new spinning-rolling process.展开更多
A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance m...A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance method.Firstly,an altitude-energy profile is designed,and the bank angle is derived analytically as the initial iteration value for the predictor-corrector method.The predictor-corrector guidance method has been improved by deriving an analytical form for predicting the range-to-go error,which greatly accelerates the iterative speed.Then,a segmented guidance algorithm is proposed.The above analytically predictor-corrector guidance method is adopted when the energy exceeds an energy threshold.When the energy is less than the threshold,the equidistant test method is used to calculate the bank angle command,which ensures guidance accuracy as well as computational efficiency.Additionally,an adaptive guidance cycle strategy is applied to reduce the computational time of the reentry guidance trajectory.Finally,the accuracy and robustness of the proposed method are verified through a series of simulations and Monte-Carlo experiments.Compared with the traditional integral method,the proposed method requires 75%less computation time on average and achieves a lower landing error.展开更多
This study describes the use of the weighted multiplicative algebraic reconstruction technique(WMART)to obtain vertical ozone profiles from limb observations performed by the scanning imaging absorption spectrometer f...This study describes the use of the weighted multiplicative algebraic reconstruction technique(WMART)to obtain vertical ozone profiles from limb observations performed by the scanning imaging absorption spectrometer for atmospheric chartography(SCIAMACHY).This technique is based on SaskMART(the combination of the multiplicative algebraic reconstruction technique and SaskTRAN radiative transfer model),which was originally developed for optical spectrometer and infrared imaging system(OSIRIS)data.One of the objectives of this study was to obtain consistent ozone profiles from the two satellites.In this study,the WMART algorithm is combined with a radiative transfer model(SCIATRAN),as well as a set of measurement vectors comprising five Hartley pairing vectors(HPVs)and one Chappuis triplet vector(CTV),to retrieve ozone profiles in the altitude range of 10–69 km.Considering that the weighting factors in WMART have a significant effect on the retrievals,we propose a novel approach to calculate the pair/triplet weighting factors using wavelength weighting functions.The results of the application of the proposed ozone retrieval scheme are compared with the SCIAMACHY v3.5 ozone product by University of Bremen and validated against profiles derived from other passive satellite observations or measured by ozonesondes.Between 18 and 55 km,the retrieved ozone profiles typically agree with data from the SCIAMACHY ozone product within 5%for tropics and middle latitudes,whereas a negative deviation exists between 35 and 50 km for northern high latitudes,with a deviation of less than 10%above 50 km.Comparison of the retrieved profiles with microwave limb sounder(MLS)v5.0 indicates that the difference is within±5%between 18 and 55 km,and an agreement within 10%is achieved in other altitudes for tropics and middle latitudes.Comparison of the retrieved profiles with OSIRIS v7.1 indicates that the average deviation is within±5%between 20 and 59 km,and difference of approximately 10%is achieved below 20 km.Compared with ozonesondes data,a general validity of the retrievals is no more than 5%between 15 and 30 km.展开更多
BACKGROUND Disorders of gut-brain interaction(DGBI)are common,but knowledge about their physiopathology is still poor,nor valid tools have been used to evaluate them in childhood.AIM To develop a psycho-gastroenterolo...BACKGROUND Disorders of gut-brain interaction(DGBI)are common,but knowledge about their physiopathology is still poor,nor valid tools have been used to evaluate them in childhood.AIM To develop a psycho-gastroenterological questionnaire(PGQ)to assess the psycho-gastroenterological profile and social characteristics of a pediatric population with and without DGBI.METHODS One hundred and nineteen Italian children(age 11-18)were included:28 outpatient patients with DGBI(Rome IV criteria)and 91 healthy controls.They filled the PGQ,faces pain scale revised(FPS-R),Bristol stool chart,ga-strointestinal symptoms rating scale,state-trait anxiety inventory,Toronto alexithymia scale 20,perceived self-efficacy in the management of negative emotions and expression of positive emotions(APEN-G,APEP-G),irritable bowel syndrome-quality of life questionnaire,school performances,tobacco use,early life events,degree of digital-ization.RESULTS Compared to controls,patients had more medical examinations(35%of them went to the doctor more than five times),a higher school performance(23%vs 13%,P<0.05),didn’t use tobacco(never vs 16%,P<0.05),had early life events(28%vs 1%P<0.05)and a higher percentage of pain classified as 4 in the FPS-R during the examination(14%vs 7%,P<0.05).CONCLUSION Pediatric outpatients with DGBI had a higher prevalence of early life events,a lower quality of life,more medical examinations rising health care costs,lower anxiety levels.展开更多
Background:The aim of this study was to analyze the bi-directional causal relation-ship between lipid profile and characteristics related to muscle atrophy by using a bi-directional Mendelian randomization(MR)analysis...Background:The aim of this study was to analyze the bi-directional causal relation-ship between lipid profile and characteristics related to muscle atrophy by using a bi-directional Mendelian randomization(MR)analysis.Methods:The appendicular lean mass(ALM),whole body fat-free mass(WBFFM)and trunk fat-free mass(TFFM)were used as genome-wide association study(GWAS)data for evaluating muscle mass;the usual walking pace(UWP)and low grip strength(LGS)were used as GWAS data for evaluating muscle strength;and the triglycerides(TG),total cholesterol(TC),high density lipoprotein cholesterol(HDL),low density lipo-protein cholesterol(LDL),apolipoprotein A-1(Apo A-1),and apolipoprotein B(Apo B)were used as GWAS data for evaluating lipid profile.For specific investigations,we mainly employed inverse variance weighting for causal estimation and MR-Egger for pleiotropy analysis.Results:MR results showed that the lipid profile predicted by genetic variants was negatively correlated with muscle mass,positively correlated with UWP,and was not causally correlated with LGS.On the other hand,the muscle mass predicted by genetic variants was negatively correlated with lipid profile,the UWP predicted by genetic variants was mainly positively correlated with lipid profile,while the LGS pre-dicted by genetic variants had no relevant causal relationship with lipid profile.Conclusions:Findings of this MR analysis suggest that hyperlipidemia may affect muscle mass and lead to muscle atrophy,but has no significant effect on muscle strength.On the other hand,increased muscle mass may reduce the incidence of dyslipidemia.展开更多
Traditional manufacturing processes for lightweight curved profiles are often associated with lengthy procedures,high costs,low efficiency,and high energy consumption.In order to solve this problem,a new staggered ext...Traditional manufacturing processes for lightweight curved profiles are often associated with lengthy procedures,high costs,low efficiency,and high energy consumption.In order to solve this problem,a new staggered extrusion(SE)process was used to form the curved profile of AZ31 magnesium alloy in this paper.The study investigates the mapping relationship between the curvature,microstructure,and mechanical properties of the formed profiles by using different eccentricities of the die.Scanning electron microscopy(SEM)and electron backscatter diffraction techniques are employed to examine the effects of different eccentricity values(e)on grain morphology,recrystallization mechanisms,texture,and Schmid factors of the products.The results demonstrate that the staggered extrusion method promotes the deep refinement of grain size in the extruded products,with an average grain size of only 15%of the original billet,reaching 12.28μm.The tensile strength and elongation of the curved profiles after extrusion under the eccentricity value of 10 mm,20 mm and 30 mm are significantly higher than those of the billet,with the tensile strength is increased to 250,270,235 MPa,and the engineering strain elongation increased to 10.5%,12.1%,15.9%.This indicates that staggered extrusion enables curvature control of the profiles while improving their strength.展开更多
The current study conducted the psychological capital profiles and the relation between profile memberships and learning burnout among undergraduates.Participants were 541 Chinese undergraduates ranging from 18 to 21 ...The current study conducted the psychological capital profiles and the relation between profile memberships and learning burnout among undergraduates.Participants were 541 Chinese undergraduates ranging from 18 to 21 years old(48.2%male;Mean years=19.54,SD=1.09 years).Latent profile analysis revealed three categories of psychological capital profile consistent high psychological capital profile(50.5%),consistent low psychological capital profile(38.1%),and dominate loss-orientated psychological capital profile(11.4%).The undergraduates in consistent high profile reported high self-efficacy,resilience,hope,and optimism.Consistent low profile characterized by a little low(~0.50 SD below the M)self-efficacy,resilience,hope,and optimism.Dominant loss-orientated profile displayed low self-efficacy,hope,optimism,but a little relatively high resilience.Specifically,undergraduates in consistent high profile exhibited low level of learning burnout;while undergraduates with low level of psychological capital(i.e.,consistent low profile and dominate loss-orientated profile)reported high level of learning burnout.The findings have theoretical significance which provides important knowledge about psychological capital profile among Chinese undergraduates.They have practical implications for student counselling and development providing person-centric support to students based on their individual psychological profiles.展开更多
This study proposes a learner profile framework based on multi-feature fusion,aiming to enhance the precision of personalized learning recommendations by integrating learners’static attributes(e.g.,demographic data a...This study proposes a learner profile framework based on multi-feature fusion,aiming to enhance the precision of personalized learning recommendations by integrating learners’static attributes(e.g.,demographic data and historical academic performance)with dynamic behavioral patterns(e.g.,real-time interactions and evolving interests over time).The research employs Term Frequency-Inverse Document Frequency(TF-IDF)for semantic feature extraction,integrates the Analytic Hierarchy Process(AHP)for feature weighting,and introduces a time decay function inspired by Newton’s law of cooling to dynamically model changes in learners’interests.Empirical results demonstrate that this framework effectively captures the dynamic evolution of learners’behaviors and provides context-aware learning resource recommendations.The study introduces a novel paradigm for learner modeling in educational technology,combining methodological innovation with a scalable technical architecture,thereby laying a foundation for the development of adaptive learning systems.展开更多
In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2...In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2D)liquid chromatography-mass spectrometry(LC-MS)method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium(CMS).A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated.For efficient and high-accuracy screening of CMS,a targeted method based on a self-constructed high resolution(HR)mass spectrum database of CMS components was established.The database was built based on the commercial MassHunter Personal Compound Database and Library(PCDL)software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening.On this basis,the unknown peaks in the CMS chromatograms were deduced and assigned.The molecular formula,group composition,and origins of a total of 99 compounds,of which the combined area percentage accounted for more than 95%of CMS components,were deduced by this 2D-LC-MS method combined with the MassHunter PCDL.This profiling method was highly efficient and could distinguish hundreds of components within 3 h,providing reliable results for quality control of this kind of complex drugs.展开更多
The traditional orbit determination method based on pulsar profile distortion can determine the six elements of the orbit.However,the estimation accuracies of these methods are limited and the computational load of a ...The traditional orbit determination method based on pulsar profile distortion can determine the six elements of the orbit.However,the estimation accuracies of these methods are limited and the computational load of a six-dimensional search is huge.To solve this problem,the differential-geometry-based Multi-dimensional Joint Position-Velocity Estimation(MJPVE)using Crab pulsar profile distortion is proposed in this paper.Firstly,through theoretical analysis,it is found that the pulsar profile distortion caused by the initial state error in some joint positionvelocity directions is very small.In other words,the accuracies of estimation in these directions are very low.Namely,the search dimension can be reduced,which in turn greatly reduces the computational load.Then,we construct the chi-squared function of the pulsar profile with respect to the estimation error in joint position-velocity direction and use differential geometry to find the joint position-velocity directions corresponding to different degrees of distortion.Finally,we utilize the grid search based on directory folding in these joint position-velocity directions corresponding to large degrees of distortion to obtain the joint position-velocity estimation.The experimental results show that compared with the grouping bi-chi-squared inversion method,MJPVE has high precision and extensive navigation information.展开更多
Vertical detection of volatile organic compounds(VOCs)is essential to expend our understanding of the distribution characteristics of VOCs and improve the predictive ability of existing air qualitymodels.In this work,...Vertical detection of volatile organic compounds(VOCs)is essential to expend our understanding of the distribution characteristics of VOCs and improve the predictive ability of existing air qualitymodels.In this work,we report the development of a sorbent tube sampler based on an unmanned aerial vehicle(UAV)platform.Vertical profile measurement of VOCs with a vertical resolution of 25mwas achieved.The sampler consists of five lightweight VOC sorbent tubes and a 5-way solenoid valve,making it available for collecting five atmospheric VOC samples in a single flight with a time response of less than 30min.The samplerweighed∼1.45 kg and had dimensions of 240mm×220mm×100mmwith small penetration loss(<10%)under 4-liter sampling conditions(flow rate of 200 mL/min).Commercialized SUMMA canisters were used as experimental controls to investigate the possible loss of self-made sampler for target compounds in the same sampling process.Comparison experiment on the ground showed that the concentration differences for all VOC species were lower than 0.14μg/m3,proving the good reliability for VOCs measurements using sorbent tube sampler.The UAV platform also incorporated online instruments for meteorological parameters and O_(3) measurement.The sampler was successfully applied to characterize the vertical profiles of VOCs up to 100 m in October 2023 in the Huaihe River Basin of China.The UAV platform and the sorbent tube sampler demonstrate good performance and will be a valuable and reliable tool for vertical VOCs measurement.展开更多
Objectives:Attachment is a profound and enduring connection to the emotion children progressively form with their parents as they mature.It significantly impacts the social and psychological development of kids and te...Objectives:Attachment is a profound and enduring connection to the emotion children progressively form with their parents as they mature.It significantly impacts the social and psychological development of kids and teenagers.This study aimed to explore the latent profiles and longitudinal transition patterns of parent-child and peer attachments among adolescents.Methods:A cohort of 914 participants from China completed the measures with a twelve-month interval.There were 46.8%boys and 53.2%girls in this survey.Latent profile analysis(LPA)was adopted to explore the distinct profiles reflecting different parent-child and peer attachment response patterns at each time point.Latent transition analysis(LTA)was used to examine the membership of distinct latent profiles and how individuals move between profiles over time.Results:Three latent profiles were found:the poor parent-child communication profile,the moderate attachment profile,and the good attachment profile.It was shown that the transition probability from the poor parent-child communication and good attachment profiles to the moderate attachment profile was higher than the transition probability between the poor parent-child communication and good attachment profiles.Patterns of parent-child and peer attachments were associated with depression and anxiety.Conclusion:This study demonstrates differences in adolescents’attachment to fathers,mothers,and peers and the need for targeted interventions for groups of adolescents with moderate levels of parent-child and peer attachment.展开更多
Objectives:Adolescents’aggression is widely studied,the underlying heterogeneity of aggression among rural Chinese boarding students remains unexplored.This study investigates the latent profiles of Chinese rural boa...Objectives:Adolescents’aggression is widely studied,the underlying heterogeneity of aggression among rural Chinese boarding students remains unexplored.This study investigates the latent profiles of Chinese rural boarding junior high school students’aggression and its correlations with moral disengagement and preference for solitude.Methods:A cross-sectional survey was conducted from 04–22 April 2022,using a convenient sampling method among 516 junior high school students from six Chinese rural boarding schools.The survey included the Aggression Questionnaire,the Moral Disengagement Scale(MDS),and the Preference for Solitude Scale(PSS).Results:Participants were divided into three latent profiles:low(36.0%),medium(50.9%),and high aggression levels(13.1%).Compared with low aggression,students who felt left-behind(minors who stay in the rural areas while one or both parents migrated to the urban areas for the work)accounted for a larger proportion in the medium aggression profile.The higher the grade level and the lower the educational level of the students’parents,the greater proportion of students in the medium and high aggression profiles.Additionally,students with high moral disengagement and preference for solitude showed a significant association with the medium aggression and high aggression profiles.Conclusions:The results demonstrate the significant group heterogeneity of aggression groups in Chinese rural boarding junior high school students.Targeted prevention and intervention measures can be carried out according to feeling left-behind,grade level,parents’education,and MDS and PSS scores.展开更多
Arrival headway,the minimum time interval between two trains that consecutively stop in the same railway yard,significantly influences overall railway capacity and becomes a bottleneck in large high-speed railway yard...Arrival headway,the minimum time interval between two trains that consecutively stop in the same railway yard,significantly influences overall railway capacity and becomes a bottleneck in large high-speed railway yards.This occurs because the leading train slows considerably along the long receiving route to the yard;while,the following train continues at top speed,creating a substantial spatial and temporal interval between them.This paper proposes a speed profile intervention(SPI)approach to reduce arrival headway.By setting appropriate speed limits in specific block sections for each train,the following train decelerates in advance,thereby shortening the interval with its predecessor.We first study the impact of speed values and locations on arrival headway theoretically,then validate our findings through a multi-agent simulation approach to quantitatively investigate the relationship between headway and SPI parameters.Simulation experiments using real-world data from the Beijing–Shanghai high-speed railway demonstrate that the SPI approach can significantly reduce arrival headway without any infrastructure modifications.To mitigate potential side effects on travel time associated with this approach,we perform an analysis that involves setting appropriate speed limit values and selecting strategic locations for their implementation.展开更多
Numerical simulations on the coupling actions between the free surface oscillation in the moonpool and the heave motion response of hulls with vertical mooring stiffness are carried out in this study,where the influen...Numerical simulations on the coupling actions between the free surface oscillation in the moonpool and the heave motion response of hulls with vertical mooring stiffness are carried out in this study,where the influences of edge profiles,including sharp and convex edge profiles,on the coupling actions are considered.Two-peak variations in the free surface oscillations in the moonpool with incident wave frequencies can be observed,which are defined as the first and second peak frequencies.The free surface oscillations and heave motion responses show in-phase and out-of-phase relationships at the first and second peak frequencies,respectively.The convex edge profiles are able to generate effective suppressing actions at the second peak frequencies.However,it is only efficient for large vertical stiffness at the first peak frequency.The relative velocity between the fluid flow along the moonpool bottom and the heave motion of the hulls is the essential reason.展开更多
基金The workis supported bythe National Natural Science Foundation of China (Grant Nos 40231010 and 40476041)
文摘With the presence of wind waves, the swaying of survey vessel may effect the quality of sub-bottom profiler records and, therefore, it is necessary to correct the distortions induced by wave action. A major issue is to distinguish wind wave effect and real bedforms such as sand waves. In this paper, a bandstop filter is designed according to the frequency features of wind wave effect to treat the distortion of seabed topography by wind waves. The technique is used to correct the sub-bottom profile in order to eliminate the wave-induced distortions for the sub-bottom profile records from the Yangtze Estuary. This study shows that the undulate seabed record is resulted from wave action, rather than the presence of sand waves, and the filtration technique helps to eliminate the wave effect and recover the real morphology of seabed and the sediment sequence underneath. In addition, a method for data processing is proposed for the case that the record indeed represents a combination of wave effects and real bedforms.
基金financially supported by the National Natural Science Foundation of China (12373092, 12273027, 11733007, 11873010, 12133010)the Nebula Talents Program of the National Astronomical Observatories, CAS+1 种基金the Sichuan Youth Science and Technology Innovation Research Team (21CXTD0038)the Innovation Team F unds of China West Normal University (KCXTD2022-6).
文摘Adaptive optics systems are the most powerful tools to counteract the image blurring caused by atmospheric turbulence,allowing ground-based telescopes to capture high-resolution images.A critical parameter influencing adaptive optics system performance is the atmospheric refractive index structure constant,C_(n)^(2),which characterizes the intensity of atmospheric optical turbulence as a function of altitude.Given its simplicity,the lunar scintillometer is the preferred method for detecting atmospheric turbulence in challenging environments like Dome A in Antarctica,where sites are still in the developmental stages and local environmental conditions are extremely harsh.However,optimizing the performance of such instruments requires carefully determining the baseline configuration of photon sensors according to each site's specific optical turbulence profile characteristics.This study uses a Monte Carlo method to identify the optimal configuration for the KunLun Turbulence Profiler(KLTP),an instrument comparable to the lunar scintillometer,developed for use at Dome A.Simulations conducted using the obtained optimal baseline configuration recovered three different model optical turbulence profiles,demonstrating the effectiveness of our method in obtaining an optimal baseline configuration.Our approach can be easily applied to baseline design for similar turbulence profilers at other sites.
基金supported by grants from the Medical Engineering Jiont Fund of the Fudan University(No.IDH2310117)。
文摘Objective:Triple-negative breast cancer(TNBC)is a highly aggressive subtype that lacks targeted therapies,leading to a poorer prognosis.However,some patients achieve long-term recurrence-free survival(RFS),offering valuable insights into tumor biology and potential treatment strategies.Methods:We conducted a comprehensive multi-omics analysis of 132 patients with American Joint Committee on Cancer(AJCC)stage III TNBC,comprising 36 long-term survivors(RFS≥8 years),62 moderate-term survivors(RFS:3-8 years),and 34 short-term survivors(RFS<3 years).Analyses investigated clinicopathological factors,whole-exome sequencing,germline mutations,copy number alterations(CNAs),RNA sequences,and metabolomic profiles.Results:Long-term survivors exhibited fewer metastatic regional lymph nodes,along with tumors showing reduced stromal fibrosis and lower Ki67 index.Molecularly,these tumors exhibited multiple alterations in genes related to homologous recombination repair,with higher frequencies of germline mutations and somatic CNAs.Additionally,tumors from long-term survivors demonstrated significant downregulation of the RTK-RAS signaling pathway.Metabolomic profiling revealed decreased levels of lipids and carbohydrate,particularly those involved in glycerophospholipid,fructose,and mannose metabolism,in long-term survival group.Multivariate Cox analysis identified fibrosis[hazard ratio(HR):12.70,95%confidence interval(95%CI):2.19-73.54,P=0.005]and RAC1copy number loss/deletion(HR:0.22,95%CI:0.06-0.83,P=0.026)as independent predictors of RFS.Higher fructose/mannose metabolism was associated with worse overall survival(HR:1.30,95%CI:1.01-1.68,P=0.045).Our findings emphasize the association between biological determinants and prolonged survival in patients with TNBC.Conclusions:Our study systematically identified the key molecular and metabolic features associated with prolonged survival in AJCC stage III TNBC,suggesting potential therapeutic targets to improve patient outcomes.
基金the National Natural Science Foundation of China(No.52275378)the National Key Laboratory for Precision Hot Processing of Metals(6142909200208)。
文摘The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficiency and low-cost manufacturing of the component.Blank design is the key part of plastic forming process design.For spinning-rolling process,the shape and size of the blank play a crucial role in process stability,deformation behavior and dimensional accuracy.So this work proposes a blank design method to determine the geometry structure and sizes of the blank.The mathematical model for calculating the blank size has been deduced based on volume conservation and neutral layer length invariance principle.The FE simulation and corresponding trial production of an actual big-tapered profiled ring disk show that the proposed blank design method is applicative.In order to obtain a preferred blank,the influence rules of blank size determined by different deformation degrees(rolling ratio k)on the spinning-rolling process are revealed by comprehensive FE simulations.Overall considering the process stability,circularity of the deformed ring disk and forming forces,a reasonable range of deformation degree(rolling ratio k)is recommended for the blank design of the new spinning-rolling process.
基金National Natural Science Foundation of China(Nos.61773387 and 62022061).
文摘A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance method.Firstly,an altitude-energy profile is designed,and the bank angle is derived analytically as the initial iteration value for the predictor-corrector method.The predictor-corrector guidance method has been improved by deriving an analytical form for predicting the range-to-go error,which greatly accelerates the iterative speed.Then,a segmented guidance algorithm is proposed.The above analytically predictor-corrector guidance method is adopted when the energy exceeds an energy threshold.When the energy is less than the threshold,the equidistant test method is used to calculate the bank angle command,which ensures guidance accuracy as well as computational efficiency.Additionally,an adaptive guidance cycle strategy is applied to reduce the computational time of the reentry guidance trajectory.Finally,the accuracy and robustness of the proposed method are verified through a series of simulations and Monte-Carlo experiments.Compared with the traditional integral method,the proposed method requires 75%less computation time on average and achieves a lower landing error.
基金supported by the National Science Foundations of China(No.61905256)the National Key Research and Development Program of China(No.2019YFC0214702)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2020439)。
文摘This study describes the use of the weighted multiplicative algebraic reconstruction technique(WMART)to obtain vertical ozone profiles from limb observations performed by the scanning imaging absorption spectrometer for atmospheric chartography(SCIAMACHY).This technique is based on SaskMART(the combination of the multiplicative algebraic reconstruction technique and SaskTRAN radiative transfer model),which was originally developed for optical spectrometer and infrared imaging system(OSIRIS)data.One of the objectives of this study was to obtain consistent ozone profiles from the two satellites.In this study,the WMART algorithm is combined with a radiative transfer model(SCIATRAN),as well as a set of measurement vectors comprising five Hartley pairing vectors(HPVs)and one Chappuis triplet vector(CTV),to retrieve ozone profiles in the altitude range of 10–69 km.Considering that the weighting factors in WMART have a significant effect on the retrievals,we propose a novel approach to calculate the pair/triplet weighting factors using wavelength weighting functions.The results of the application of the proposed ozone retrieval scheme are compared with the SCIAMACHY v3.5 ozone product by University of Bremen and validated against profiles derived from other passive satellite observations or measured by ozonesondes.Between 18 and 55 km,the retrieved ozone profiles typically agree with data from the SCIAMACHY ozone product within 5%for tropics and middle latitudes,whereas a negative deviation exists between 35 and 50 km for northern high latitudes,with a deviation of less than 10%above 50 km.Comparison of the retrieved profiles with microwave limb sounder(MLS)v5.0 indicates that the difference is within±5%between 18 and 55 km,and an agreement within 10%is achieved in other altitudes for tropics and middle latitudes.Comparison of the retrieved profiles with OSIRIS v7.1 indicates that the average deviation is within±5%between 20 and 59 km,and difference of approximately 10%is achieved below 20 km.Compared with ozonesondes data,a general validity of the retrievals is no more than 5%between 15 and 30 km.
文摘BACKGROUND Disorders of gut-brain interaction(DGBI)are common,but knowledge about their physiopathology is still poor,nor valid tools have been used to evaluate them in childhood.AIM To develop a psycho-gastroenterological questionnaire(PGQ)to assess the psycho-gastroenterological profile and social characteristics of a pediatric population with and without DGBI.METHODS One hundred and nineteen Italian children(age 11-18)were included:28 outpatient patients with DGBI(Rome IV criteria)and 91 healthy controls.They filled the PGQ,faces pain scale revised(FPS-R),Bristol stool chart,ga-strointestinal symptoms rating scale,state-trait anxiety inventory,Toronto alexithymia scale 20,perceived self-efficacy in the management of negative emotions and expression of positive emotions(APEN-G,APEP-G),irritable bowel syndrome-quality of life questionnaire,school performances,tobacco use,early life events,degree of digital-ization.RESULTS Compared to controls,patients had more medical examinations(35%of them went to the doctor more than five times),a higher school performance(23%vs 13%,P<0.05),didn’t use tobacco(never vs 16%,P<0.05),had early life events(28%vs 1%P<0.05)and a higher percentage of pain classified as 4 in the FPS-R during the examination(14%vs 7%,P<0.05).CONCLUSION Pediatric outpatients with DGBI had a higher prevalence of early life events,a lower quality of life,more medical examinations rising health care costs,lower anxiety levels.
基金Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2021A1515220030Hunan Provincial Clinical Medical Technology Innovation Guiding Project,Grant/Award Number:2020SK53307+2 种基金Hunan Provincial Health Commission,Grant/Award Number:20201902Natural Science Foundation of Hunan Province,Grant/Award Number:2020JJ8043Project of Hunan Provincial Health,Grant/Award Number:c2019133。
文摘Background:The aim of this study was to analyze the bi-directional causal relation-ship between lipid profile and characteristics related to muscle atrophy by using a bi-directional Mendelian randomization(MR)analysis.Methods:The appendicular lean mass(ALM),whole body fat-free mass(WBFFM)and trunk fat-free mass(TFFM)were used as genome-wide association study(GWAS)data for evaluating muscle mass;the usual walking pace(UWP)and low grip strength(LGS)were used as GWAS data for evaluating muscle strength;and the triglycerides(TG),total cholesterol(TC),high density lipoprotein cholesterol(HDL),low density lipo-protein cholesterol(LDL),apolipoprotein A-1(Apo A-1),and apolipoprotein B(Apo B)were used as GWAS data for evaluating lipid profile.For specific investigations,we mainly employed inverse variance weighting for causal estimation and MR-Egger for pleiotropy analysis.Results:MR results showed that the lipid profile predicted by genetic variants was negatively correlated with muscle mass,positively correlated with UWP,and was not causally correlated with LGS.On the other hand,the muscle mass predicted by genetic variants was negatively correlated with lipid profile,the UWP predicted by genetic variants was mainly positively correlated with lipid profile,while the LGS pre-dicted by genetic variants had no relevant causal relationship with lipid profile.Conclusions:Findings of this MR analysis suggest that hyperlipidemia may affect muscle mass and lead to muscle atrophy,but has no significant effect on muscle strength.On the other hand,increased muscle mass may reduce the incidence of dyslipidemia.
基金Project(JQ2022E004)supported by the Natural Science Foundation of Heilongjiang Province,China。
文摘Traditional manufacturing processes for lightweight curved profiles are often associated with lengthy procedures,high costs,low efficiency,and high energy consumption.In order to solve this problem,a new staggered extrusion(SE)process was used to form the curved profile of AZ31 magnesium alloy in this paper.The study investigates the mapping relationship between the curvature,microstructure,and mechanical properties of the formed profiles by using different eccentricities of the die.Scanning electron microscopy(SEM)and electron backscatter diffraction techniques are employed to examine the effects of different eccentricity values(e)on grain morphology,recrystallization mechanisms,texture,and Schmid factors of the products.The results demonstrate that the staggered extrusion method promotes the deep refinement of grain size in the extruded products,with an average grain size of only 15%of the original billet,reaching 12.28μm.The tensile strength and elongation of the curved profiles after extrusion under the eccentricity value of 10 mm,20 mm and 30 mm are significantly higher than those of the billet,with the tensile strength is increased to 250,270,235 MPa,and the engineering strain elongation increased to 10.5%,12.1%,15.9%.This indicates that staggered extrusion enables curvature control of the profiles while improving their strength.
基金supported by Hunan Province Education Department Outstanding Youth Project(23B1131)Hunan Province Education Science Fourteenth Five-Year Plan Project(XJK24BXL003).
文摘The current study conducted the psychological capital profiles and the relation between profile memberships and learning burnout among undergraduates.Participants were 541 Chinese undergraduates ranging from 18 to 21 years old(48.2%male;Mean years=19.54,SD=1.09 years).Latent profile analysis revealed three categories of psychological capital profile consistent high psychological capital profile(50.5%),consistent low psychological capital profile(38.1%),and dominate loss-orientated psychological capital profile(11.4%).The undergraduates in consistent high profile reported high self-efficacy,resilience,hope,and optimism.Consistent low profile characterized by a little low(~0.50 SD below the M)self-efficacy,resilience,hope,and optimism.Dominant loss-orientated profile displayed low self-efficacy,hope,optimism,but a little relatively high resilience.Specifically,undergraduates in consistent high profile exhibited low level of learning burnout;while undergraduates with low level of psychological capital(i.e.,consistent low profile and dominate loss-orientated profile)reported high level of learning burnout.The findings have theoretical significance which provides important knowledge about psychological capital profile among Chinese undergraduates.They have practical implications for student counselling and development providing person-centric support to students based on their individual psychological profiles.
基金This work is supported by the Ministry of Education of Humanities and Social Science projects in China(No.20YJCZH124)Guangdong Province Education and Teaching Reform Project No.640:Research on the Teaching Practice and Application of Online Peer Assessment Methods in the Context of Artificial Intelligence.
文摘This study proposes a learner profile framework based on multi-feature fusion,aiming to enhance the precision of personalized learning recommendations by integrating learners’static attributes(e.g.,demographic data and historical academic performance)with dynamic behavioral patterns(e.g.,real-time interactions and evolving interests over time).The research employs Term Frequency-Inverse Document Frequency(TF-IDF)for semantic feature extraction,integrates the Analytic Hierarchy Process(AHP)for feature weighting,and introduces a time decay function inspired by Newton’s law of cooling to dynamically model changes in learners’interests.Empirical results demonstrate that this framework effectively captures the dynamic evolution of learners’behaviors and provides context-aware learning resource recommendations.The study introduces a novel paradigm for learner modeling in educational technology,combining methodological innovation with a scalable technical architecture,thereby laying a foundation for the development of adaptive learning systems.
基金support from the Science Research Program Project for Drug Regulation,Jiangsu Medical Products Administration,China(Grant No.:202207)the National Drug Standards Revision Project,China(Grant No.:2023Y41)+1 种基金the National Natural Science Foundation of China(Grant No.:22276080)the Foreign Expert Project,China(Grant No.:G2022014096L).
文摘In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2D)liquid chromatography-mass spectrometry(LC-MS)method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium(CMS).A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated.For efficient and high-accuracy screening of CMS,a targeted method based on a self-constructed high resolution(HR)mass spectrum database of CMS components was established.The database was built based on the commercial MassHunter Personal Compound Database and Library(PCDL)software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening.On this basis,the unknown peaks in the CMS chromatograms were deduced and assigned.The molecular formula,group composition,and origins of a total of 99 compounds,of which the combined area percentage accounted for more than 95%of CMS components,were deduced by this 2D-LC-MS method combined with the MassHunter PCDL.This profiling method was highly efficient and could distinguish hundreds of components within 3 h,providing reliable results for quality control of this kind of complex drugs.
基金supported in part by the National Natural Science Foundation of China(Nos.61873196,62373030,61772187)the Innovation Program for Quantum Science and Technology(No.2021ZD0303400)。
文摘The traditional orbit determination method based on pulsar profile distortion can determine the six elements of the orbit.However,the estimation accuracies of these methods are limited and the computational load of a six-dimensional search is huge.To solve this problem,the differential-geometry-based Multi-dimensional Joint Position-Velocity Estimation(MJPVE)using Crab pulsar profile distortion is proposed in this paper.Firstly,through theoretical analysis,it is found that the pulsar profile distortion caused by the initial state error in some joint positionvelocity directions is very small.In other words,the accuracies of estimation in these directions are very low.Namely,the search dimension can be reduced,which in turn greatly reduces the computational load.Then,we construct the chi-squared function of the pulsar profile with respect to the estimation error in joint position-velocity direction and use differential geometry to find the joint position-velocity directions corresponding to different degrees of distortion.Finally,we utilize the grid search based on directory folding in these joint position-velocity directions corresponding to large degrees of distortion to obtain the joint position-velocity estimation.The experimental results show that compared with the grouping bi-chi-squared inversion method,MJPVE has high precision and extensive navigation information.
基金supported by the National Natural Science Foundation of China(Nos.42022051,U21A2028,and 42305124)the Youth Innovation Promotion Association CAS(No.Y202089)the HFIPS Director’s Fund(Nos.BJPY2023A02,YZJJ202101,and YZJJ2023QN01).
文摘Vertical detection of volatile organic compounds(VOCs)is essential to expend our understanding of the distribution characteristics of VOCs and improve the predictive ability of existing air qualitymodels.In this work,we report the development of a sorbent tube sampler based on an unmanned aerial vehicle(UAV)platform.Vertical profile measurement of VOCs with a vertical resolution of 25mwas achieved.The sampler consists of five lightweight VOC sorbent tubes and a 5-way solenoid valve,making it available for collecting five atmospheric VOC samples in a single flight with a time response of less than 30min.The samplerweighed∼1.45 kg and had dimensions of 240mm×220mm×100mmwith small penetration loss(<10%)under 4-liter sampling conditions(flow rate of 200 mL/min).Commercialized SUMMA canisters were used as experimental controls to investigate the possible loss of self-made sampler for target compounds in the same sampling process.Comparison experiment on the ground showed that the concentration differences for all VOC species were lower than 0.14μg/m3,proving the good reliability for VOCs measurements using sorbent tube sampler.The UAV platform also incorporated online instruments for meteorological parameters and O_(3) measurement.The sampler was successfully applied to characterize the vertical profiles of VOCs up to 100 m in October 2023 in the Huaihe River Basin of China.The UAV platform and the sorbent tube sampler demonstrate good performance and will be a valuable and reliable tool for vertical VOCs measurement.
基金funded by the Shihezi University Innovation and Development Special Project“Research and Application of Knowledge Graph Based Big Data Platform for the Development Trend of College Students’Mental Health”(CXFZSK202205)by the China Young Pioneers Research Topic General Topic(2022YB16).
文摘Objectives:Attachment is a profound and enduring connection to the emotion children progressively form with their parents as they mature.It significantly impacts the social and psychological development of kids and teenagers.This study aimed to explore the latent profiles and longitudinal transition patterns of parent-child and peer attachments among adolescents.Methods:A cohort of 914 participants from China completed the measures with a twelve-month interval.There were 46.8%boys and 53.2%girls in this survey.Latent profile analysis(LPA)was adopted to explore the distinct profiles reflecting different parent-child and peer attachment response patterns at each time point.Latent transition analysis(LTA)was used to examine the membership of distinct latent profiles and how individuals move between profiles over time.Results:Three latent profiles were found:the poor parent-child communication profile,the moderate attachment profile,and the good attachment profile.It was shown that the transition probability from the poor parent-child communication and good attachment profiles to the moderate attachment profile was higher than the transition probability between the poor parent-child communication and good attachment profiles.Patterns of parent-child and peer attachments were associated with depression and anxiety.Conclusion:This study demonstrates differences in adolescents’attachment to fathers,mothers,and peers and the need for targeted interventions for groups of adolescents with moderate levels of parent-child and peer attachment.
基金the General project of the“14th Five-Year Plan”of Education Science of Gansu Province in 2023:“Research on the Integration Strategy of Rural Primary School Labor Education and Other Disciplines under the Background of Rural Revitalization”(Project number:GS[2023]GHB1420)Gansu Provincial University Curriculum Ideological and Political Demonstration Project“Exploration and Practice of Ideological and Political Courses in Pre-School EducationMajors from the Perspective of Three Educations:A Case study of Pre-School EducationHistory”(Project No.:GSkcsz-2021-094).
文摘Objectives:Adolescents’aggression is widely studied,the underlying heterogeneity of aggression among rural Chinese boarding students remains unexplored.This study investigates the latent profiles of Chinese rural boarding junior high school students’aggression and its correlations with moral disengagement and preference for solitude.Methods:A cross-sectional survey was conducted from 04–22 April 2022,using a convenient sampling method among 516 junior high school students from six Chinese rural boarding schools.The survey included the Aggression Questionnaire,the Moral Disengagement Scale(MDS),and the Preference for Solitude Scale(PSS).Results:Participants were divided into three latent profiles:low(36.0%),medium(50.9%),and high aggression levels(13.1%).Compared with low aggression,students who felt left-behind(minors who stay in the rural areas while one or both parents migrated to the urban areas for the work)accounted for a larger proportion in the medium aggression profile.The higher the grade level and the lower the educational level of the students’parents,the greater proportion of students in the medium and high aggression profiles.Additionally,students with high moral disengagement and preference for solitude showed a significant association with the medium aggression and high aggression profiles.Conclusions:The results demonstrate the significant group heterogeneity of aggression groups in Chinese rural boarding junior high school students.Targeted prevention and intervention measures can be carried out according to feeling left-behind,grade level,parents’education,and MDS and PSS scores.
基金supported by the National Natural Science Foundation of China(Nos.52232011 and 52272324)the National Natural Science Foundation of Sichuan Province(No.2022NSFSC0397).
文摘Arrival headway,the minimum time interval between two trains that consecutively stop in the same railway yard,significantly influences overall railway capacity and becomes a bottleneck in large high-speed railway yards.This occurs because the leading train slows considerably along the long receiving route to the yard;while,the following train continues at top speed,creating a substantial spatial and temporal interval between them.This paper proposes a speed profile intervention(SPI)approach to reduce arrival headway.By setting appropriate speed limits in specific block sections for each train,the following train decelerates in advance,thereby shortening the interval with its predecessor.We first study the impact of speed values and locations on arrival headway theoretically,then validate our findings through a multi-agent simulation approach to quantitatively investigate the relationship between headway and SPI parameters.Simulation experiments using real-world data from the Beijing–Shanghai high-speed railway demonstrate that the SPI approach can significantly reduce arrival headway without any infrastructure modifications.To mitigate potential side effects on travel time associated with this approach,we perform an analysis that involves setting appropriate speed limit values and selecting strategic locations for their implementation.
基金supported by the National Natural Science Foundation of China(Grant Nos.52371267 and 52171250).
文摘Numerical simulations on the coupling actions between the free surface oscillation in the moonpool and the heave motion response of hulls with vertical mooring stiffness are carried out in this study,where the influences of edge profiles,including sharp and convex edge profiles,on the coupling actions are considered.Two-peak variations in the free surface oscillations in the moonpool with incident wave frequencies can be observed,which are defined as the first and second peak frequencies.The free surface oscillations and heave motion responses show in-phase and out-of-phase relationships at the first and second peak frequencies,respectively.The convex edge profiles are able to generate effective suppressing actions at the second peak frequencies.However,it is only efficient for large vertical stiffness at the first peak frequency.The relative velocity between the fluid flow along the moonpool bottom and the heave motion of the hulls is the essential reason.
