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Associations of waist circumference with sex steroid hormones among 4031 USA children and adolescents

Asian Journal of Andrology 2023年第4期25卷 505-511页

作者： Zhong-Yuan Wang Bao-Chao Li Jia-Jun Xing Shou-Yong Liu Tong-Tong Zhang ai-ming xu Zeng-Jun Wang Department of Urology First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

In the recent decades,obesity rates among children and adolescents,especially males,have increased significantly.This worldwide phenomenon is thought to significantly affect the levels of sex hormones.However,the association between waist circumference(a marker of abdominal obesity)and sex hormone levels in children and adolescents is unknown.In this study,4031 participants aged 6–19 years from the United States National Health and Nutrition Examination Survey(NHANES)in the USA were enrolled in this study.The common confounders of age,race,body mass index,educational level,family income,diabetes,and time of sample collection were also collected.The participants missing any of the above information were excluded from the study.We used multiple linear regression and other multiple statistics to assess the associations between waist circumference and serum testosterone,estradiol,sex hormone-binding globulin(SHBG),free androgen index(Fai),and testosterone/estradiol ratio(T/E2).Waist circumference remained associated with sex hormone levels in children and adolescents after controlling for covariates.As waist circumference increases,testosterone levels in children and adolescents show an overall decline after a brief increase,with the inflection point for waist circumference of 65–66 cm.In addition,waist circumference positively correlates with estradiol levels in male children(β=0.007,95%confidence interval:0.004–0.009).Moreover,circulating SHBG decreases in children and adolescents as waist circumference increases.In conclusion,this study highlighted waist circumference as a vital indicator affecting sex hormone levels in children and adolescents.

关键词： adolescents children NHANES sex steroid hormones waist circumference

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Design of an automated robotic microinjection system for batch injection of zebrafish embryos and larvae

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Microsystems & Nanoengineering 2024年第1期10卷 89-103页

作者： Zhongyi Guo Nana ai Wei Ge Qingsong xu Department of Electromechanical Engineering Faculty of Science and TechnologyUniversity of MacaoMacaoChina Department of Biomedical Sciences and Centre of Reproduction Development and Aging(CRDA)Faculty of Health SciencesUniversity of MacaoMacaoChina

This paper presents the design of a vision-based automated robotic microinjection system for batch injection of both zebrafish embryos and larvae.A novel visual recognition algorithm based on an automatic threshold and excessive dilatation is introduced to accurately identify the center of zebrafish embryos and larval yolks.A corresponding software system is developed using the producer-consumer model as the framework structure,and a friendly user interface is designed to allow operators to choose from a range of desired functions according to their different needs.In addition,a novel microstructural agarose device is designed and fabricated to simultaneously immobilize mixed batches of embryos and larvae.Moreover,a prototype microinjection system is fabricated by integrating hardware devices with visual algorithms.An experimental study is conducted to verify the performance of the robotic microinjection system.The results show that the reported system can accurately identify zebrafish embryos and larvae and efficiently complete batch microinjection tasks of the mixtures with an injection success rate of 92.05%in 13.88 s per sample.Compared with manual and existing microinjection systems,the proposed system demonstrates the merits of versatility,excellent efficiency,high success rate,high survival rate,and sufficient stability.

关键词： zebra automated hardware

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Diabetes mellitus in patients with type 1 autoimmune pancreatitis at diagnosis and after corticosteroid therapy

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 393-398页

作者： Mei-Zi Li Tao Guo Yun-Lu Feng Sheng-Yu Zhang Xiao-Yin Bai Xi Wu Kai xu ai-ming Yang Department of Gastroenterology State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China Department of Radiology Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China

Background:A high prevalence of diabetes mellitus(DM)coexisting with autoimmune pancreatitis(aiP)is observed.However,evidence on the circumstances under which corticosteroid therapy(CST)for aiP improves or worsens DM is scarce.This study aimed to demonstrate and identify predictors of DM control under the influence of CST.Methods:Patients diagnosed with type 1 aiP were enrolled from a prospectively maintained cohort and were classified into three groups according to the chronology in which aiP and DM were diagnosed:pre-existing DM(pDM),concurrent DM(cDM),and non-DM(nDM).The responses of DM to CST were assessed when corticosteroid was ceased or tapered to a maintenance dose and classified as‘improvement’and‘non-improvement’(including‘no change’and‘exacerbation’).Results:Among 101 patients with type 1 aiP,52(51.5%)patients were complicated with DM at the time of aiP diagnosis,with 36 patients in the cDM group and 16 patients in the pDM group.The incidences of diffuse pancreatic swelling(72.2%)and pancreatic body/tail involvement(91.7%)were significantly higher in the cDM group than in both the pDM and nDM groups.Of the 52 patients with DM,CST was administered in 48 cases.Multivariate logistic analysis identified that elevated serum gamma-glutamyl transferase(GGT)level at aiP diagnosis[odds ratio(OR)=0.032,95%confidence interval(CI):0.003-0.412,P=0.008]and pancreatic atrophy after CST(OR=0.027,95%CI:0.003-0.295,P=0.003)were negatively associated with DM control improvement.Conclusions:Patients with diffuse pancreatic swelling and pancreatic body/tail involvement in pancreatitis tended to be complicated with cDM at aiP diagnosis.CST exerted a beneficial effect on the clinical course of DM in nearly half of the aiP patients complicated with DM at diagnosis,particularly in those without elevated serum GGT levels at diagnosis and who did not experience pancreatic atrophy after CST.

关键词： Type 1 autoimmune pancreatitis Diabetes mellitus Corticosteroid therapy Predictive factor Pancreatic atrophy

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Reliability ensemble averaging reduces surface wind speed projection uncertainties in the 21st century over China

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Advances in Climate Change Research 2024年第2期15卷 222-229页

作者： Zheng-Tai ZHANG Chang-ai xu Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

Accurate prediction of future surface wind speed(SWS)changes is the basis of scientific planning for wind turbines.Most studies have projected SWS changes in the 21st century over China on the basis of the multi-model ensemble(MME)of the 6th Coupled Model Intercomparison Project(CMIP6).However,the simulation capability for SWS varies greatly in CMIP6 multi-models,so the MME results still have large uncertainties.In this study,we used the reliability ensemble averaging(REA)method to assign each model different weights according to their performances in simulating historical SWS changes and project the SWS under different shared socioeconomic pathways(SSPs)in 2015-2099.The results indicate that REA considerably improves the SWS simulation capacity of CMIP6,eliminating the overestimation of SWS by the MME and increasing the simulation capacity of spatial distribution.The spatial correlations with observations increased from 0.56 for the MME to 0.85 for REA.Generally,REA could eliminate the overestimation of the SWS by 33%in 2015-2099.Except for southeastern China,the SWS generally decreases over China in the near term(2020-2049)and later term(2070-2099),particularly under high-emission scenarios.The SWS reduction projected by REA is twice as high as that by the MME in the near term,reaching-4%to-3%.REA predicts a larger area of increased SWS in the later term,which expands from southeastern China to eastern China.This study helps to reduce the projected SWS uncertainties.

关键词： Surface wind speed Uncertainty Multi-model ensemble Reliability ensemble averaging CMIP6

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Numerical analysis of wind effects on aerodynamic characteristics of a ducted fan

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Chinese Journal of Aeronautics 2024年第5期37卷 263-280页

作者： Yiwei LUO Tianfu ai Yuhang HE Bin xu Yuping QIAN Yangjun ZHANG State Key Laboratory of Intelligent Green Vehicle and Mobility School of Vehicle and MobilityTsinghua UniversityBeijing 100084China Key Laboratory of Conveyance and Equipment Ministry of Education East China Jiaotong UniversityNanchang 330013China Vehicle Research Center School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Ducted fans have been extensively used in Unmanned Aerial Vehicles(UAVs)for a variety of missions because of high efficiency,high safety and low noise.Wind,as a kind of typical meteorological condition,brings significant aerodynamic interference to the ducted fan,which seriously threatens flight stability and safety.In this work,the numerical simulation with the Unsteady Reynolds Averaged Navier-Stokes(URANS)method and the sliding mesh technique is performed to evaluate the steady wind effect.The results show that the wind will lead to serious unsteady effects in the flow field,and the thrust fluctuates at the blade passing frequency of 200 Hz.As the wind speed increases,the rotor thrust increases,the duct thrust decreases,and the total thrust changes little.Flow instability may occur when the wind speed exceeds 8 m/s.As the angle of low-speed wind increases,the rotor thrust changes little,the duct thrust increases,and the total thrust increases.In addition,we figure out that cases with the same crosswind ratio are similar in results,and increasing the rotating speed or fan radius is beneficial to performance improvement in wind.The findings are essential to the ducted fan design and UAV flight control design for stable and safe operations in wind conditions.

关键词： Unmanned Aerial Vehicle(UAV) Ducted fan Wind effect Thrust fluctuations Computational Fluid Dynamics(CFD)

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Improved nuclear mass formula with an additional term from the Fermi gas model

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Nuclear Science and Techniques 2024年第5期35卷 131-138页

作者： Xiao-Yu xu Li Deng ai-Xi Chen Hang Yang Amir Jalili Han-Kui Wang School of Science Zhejiang Sci-Tech UniversityHangzhou 310018China

Nuclear mass is a fundamental property of nuclear physics and a necessary input in nuclear astrophysics.Owing to the complexity of atomic nuclei and nonperturbative strong interactions,conventional physical models cannot completely describe nuclear binding energies.In this study,the mass formula was improved by considering an additional term from the Fermi gas model.All nuclear masses in the Atomic Mass Evaluation Database were reproduced with a root-mean-square deviation(RMSD)of -1.86 MeV(1.92 MeV).The new mass formula exhibits good performance in the neutron-rich nuclear region.The RMSD decreases to 0.393 MeV when the ratio of the neutron number to the proton number is≥1.6.

关键词： Nuclear mass formula Neutron-rich nuclei Fermi-gas model

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Genetic Analysis of Two Novel GPI Variants Disrupting H Bonds and Localization Characteristics of 55 Gene Variants Associated with Glucose-6-phosphate Isomerase Deficiency

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Current Medical Science 2024年第2期44卷 426-434页

作者： Bi-xin XI Si-ying LIU Yu-ting xu De-dong ZHANG Qun HU ai-guo LIU Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Glucose-6-phosphate isomerase(GPI)deficiency is a rare hereditary nonspherocytic hemolytic anemia caused by GPI gene variants.This disorder exhibits wide heterogeneity in its clinical manifestations and molecular characteristics,often posing challenges for precise diagnoses using conventional methods.To this end,this study aimed to identify the novel variants responsible for GPI deficiency in a Chinese family.Methods:The clinical manifestations of the patient were summarized and analyzed for GPI deficiency phenotype diagnosis.Novel compound heterozygous variants of the GPI gene,c.174C>A(p.Asn58Lys)and c.1538G>T(p.Trp513Leu),were identified using whole-exome and Sanger sequencing.The AlphaFold program and Chimera software were used to analyze the effects of compound heterozygous variants on GPI structure.Results:By characterizing 53 GPI missense/nonsense variants from previous literature and two novel missense variants identified in this study,we found that most variants were located in exons 3,4,12,and 18,with a few localized in exons 8,9,and 14.This study identified novel compound heterozygous variants associated with GPI deficiency.These pathogenic variants disrupt hydrogen bonds formed by highly conserved GPI amino acids.Conclusion:Early family-based sequencing analyses,especially for patients with congenital anemia,can help increase diagnostic accuracy for GPI deficiency,improve child healthcare,and enable genetic counseling.

关键词： glucose-6-phosphate isomerase deficiency whole-exome sequencing compound heterozygous variants genetic characterization hydrogen bond

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Attitude Tracking Control for Rigid Spacecraft with Arbitrary Convergence Time

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Journal of Systems Science & Complexity 2024年

作者： xu Yu-Tian WU ai-Guo Guangdong Provincial Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics Harbin Institute of Technology (Shenzhen) Key University Laboratory of Mechanism & Machine Theory and Intelligent Unmanned Systems of Guangdong Harbin Institute of Technology (Shenzhen) Department of Automation Harbin Institute of Technology (Shenzhen) Shenzhen 518055 China4HIT Wuhu Robot Technology Research Institute

In this paper, attitude tracking control with arbitrary convergence time for rigid spacecraft is considered. First, a novel time-varying sliding function is proposed to achieve free-will arbitrary time convergence when the system states reside on the sliding surface. With such a sliding function, an attitude tracking controller is designed to guarantee that the states of the closed-loop system converge to the sliding surface within a predetermined time in the presence of external disturbances. The free-will arbitrary time convergences of the closed-loop system and sliding function are illustrated by numerical simulations.

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The FAST all sky HI survey(FASHI):The first release of catalog

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 112-133页

作者： Chuan-Peng Zhang ming Zhu Peng Jiang Cheng Cheng Jing Wang Jie Wang Jin-Long xu Xiao-Lan Liu Nai-Ping Yu Lei Qian Haiyang Yu Mei ai Yingjie Jing Chen xu Ziming Liu Xin Guan Chun Sun Qingliang Yang Menglin Huang Qiaoli Hao FAST Collaboration Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China National Astronomical Observatories Chinese Academy of Sciences(CAS)Beijing 100101China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

The FAST All Sky HI survey(FASHI)was designed to cover the entire sky observable by the Five-hundred-meter Aperture Spherical radio Telescope(FAST),spanning approximately 22000 square degrees of declination between-14°and+66°,and in the frequency range of 1050-1450 MHz,with the expectation of eventually detecting more than 100000 HI sources.Between August 2020 and June 2023,FASHI had covered more than 7600 square degrees,which is approximately 35%of the total sky observable by FAST.It has a median detection sensitivity of around 0.76 m Jy beam-1and a spectral line velocity resolution of~6.4 km s-1at a frequency of~1.4 GHz.As of now,a total of 41741 extragalactic HI sources have been detected in the frequency range 1305.5-1419.5 MHz,corresponding to a redshift limit of z■0.09.By cross-matching FASHI sources with the Siena Galaxy Atlas(SGA)and the Sloan Digital Sky Survey(SDSS)catalogs,we found that 16972(40.7%)sources have spectroscopic redshifts and 10975(26.3%)sources have only photometric redshifts.Most of the remaining 13794(33.0%)HI sources are located in the direction of the Galactic plane,making their optical counterparts difficult to identify due to high extinction or high contamination of Galactic stellar sources.Based on current survey results,the FASHI survey is an unprecedented blind extragalactic H I survey.It has higher spectral and spatial resolution and broader coverage than the Arecibo Legacy Fast ALFA Survey(ALFALFA).When completed,FASHI will provide the largest extragalactic HI catalog and an objective view of HI content and large-scale structure in the local universe.

关键词： surveys redshifts galaxies telescope radio lines HI line

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A survey on model-based reinforcement learning

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Science China(Information Sciences) 2024年第2期67卷 59-84页

作者： Fan-ming LUO Tian xu Hang Lai Xiong-Hui CHEN Weinan ZHANG Yang YU National Key Laboratory for Novel Software Technology Nanjing University Polixir. ai Department of Computer Science and Engineering Shanghai Jiao Tong University

Reinforcement learning(RL) interacts with the environment to solve sequential decision-making problems via a trial-and-error approach. Errors are always undesirable in real-world applications, even though RL excels at playing complex video games that permit several trial-and-error attempts. To improve sample efficiency and thus reduce errors, model-based reinforcement learning(MBRL) is believed to be a promising direction, as it constructs environment models in which trial-and-errors can occur without incurring actual costs. In this survey, we investigate MBRL with a particular focus on the recent advancements in deep RL. There is a generalization error between the learned model of a non-tabular environment and the actual environment. Consequently, it is crucial to analyze the disparity between policy training in the environment model and that in the actual environment, guiding algorithm design for improved model learning, model utilization, and policy training. In addition, we discuss the recent developments of model-based techniques in other forms of RL, such as offline RL, goal-conditioned RL, multi-agent RL, and meta-RL. Furthermore,we discuss the applicability and benefits of MBRL for real-world tasks. Finally, this survey concludes with a discussion of the promising future development prospects for MBRL. We believe that MBRL has great unrealized potential and benefits in real-world applications, and we hope this survey will encourage additional research on MBRL.

关键词： reinforcement learning model-based reinforcement learning planning model learning model learning with reduced error model usage

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