Objective To analyze trends in the depressive disorder burden across BRICS Plus countries and their associations with age,period,and cohort effects.Methods Prevalence,incidence,and disability-adjusted life years(DALYs...Objective To analyze trends in the depressive disorder burden across BRICS Plus countries and their associations with age,period,and cohort effects.Methods Prevalence,incidence,and disability-adjusted life years(DALYs)estimates of the depressive disorder burden were obtained from the Global Burden of Disease Study,2021.This study further assessed the period and cohort effects on depressive disorders from 1992 to 2021 using an age-periodcohort model.Results In 2021,152.6 million people had depressive disorders across the BRICS Plus countries,showing an increase of 85.6%from 1990,which caused 23.7 million DALYs.The age-standardized prevalence rate(ASPR)of depressive disorders declined by 4.1%from 1990 to 2019,followed by a substantial increase(11.3%)from 2019 to 2021.Furthermore,period and cohort effects showed that the depressive disorder burden increased over time and in the recent birth cohort.Meanwhile,the depressive disorder burden increased among adolescents,young adults,and older adults in the BRICS Plus group.Ultimately,projections for 2050 suggest a 150.0%increase in the ASPR.Conclusion This study revealed a heavy depressive disorder burden across BRICS Plus countries,especially among adolescents,young adults,and older adults.This highlights the need to strengthen specific public health strategies and policies targeting populations with different priorities.展开更多
Multi-stage Mesozoic thrust-nappe and extensional structures are distributed in the east segment of the Southeast Yangtze Block situated in the junction region of Zhejiang-Jiangxi-Anhui provinces. The features and gen...Multi-stage Mesozoic thrust-nappe and extensional structures are distributed in the east segment of the Southeast Yangtze Block situated in the junction region of Zhejiang-Jiangxi-Anhui provinces. The features and genetic mechanism of the deformations were analyzed after a detailed field observation of their distribution, geometry, and kinematics. In addition, the time sequences of the thrust and extensional structures were determined by combining the results of the comparative analysis with the chronological evidence of strata and magmatic rocks cut by a fault or formed after a fault according to field facts. This study identified three stages of the nappe structures and at least two stages of the extensional structures during the Mesozoic. The geotectonic setting of the nappe and extensional structures was considered to be related to the different geodynamics in the study area including the Early Mesozoic geological event, i.e., N-S compression, forming Lantian fault, etc.;the Late Mesozoic flat-slab subduction, forming Xiaoxi thrust fault and tectonic window;and the roll-back of the paleoPacific Plate, forming extensional structures like basin marginal fault;the last compression, forming Wucheng-Shenxian fault. These findings provide additional evidence for remodeling the tectonic and geodynamic evolution of Southeast China.展开更多
Offline reinforcement learning leverages previously collected offline datasets to learn optimal policies with no necessity to access the real environment.Such a paradigm is also desirable for multi-agent reinforcement...Offline reinforcement learning leverages previously collected offline datasets to learn optimal policies with no necessity to access the real environment.Such a paradigm is also desirable for multi-agent reinforcement learning(MARL)tasks,given the combinatorially increased interactions among agents and with the environment.However,in MARL,the paradigm of offline pre-training with online fine-tuning has not been studied,nor even datasets or benchmarks for offline MARL research are available.In this paper,we facilitate the research by providing large-scale datasets and using them to examine the usage of the decision transformer in the context of MARL.We investigate the generalization of MARL offline pre-training in the following three aspects:1)between single agents and multiple agents,2)from offline pretraining to online fine tuning,and 3)to that of multiple downstream tasks with few-shot and zero-shot capabilities.We start by introducing the first offline MARL dataset with diverse quality levels based on the StarCraftII environment,and then propose the novel architecture of multi-agent decision transformer(MADT)for effective offline learning.MADT leverages the transformer′s modelling ability for sequence modelling and integrates it seamlessly with both offline and online MARL tasks.A significant benefit of MADT is that it learns generalizable policies that can transfer between different types of agents under different task scenarios.On the StarCraft II offline dataset,MADT outperforms the state-of-the-art offline reinforcement learning(RL)baselines,including BCQ and CQL.When applied to online tasks,the pre-trained MADT significantly improves sample efficiency and enjoys strong performance in both few-short and zero-shot cases.To the best of our knowledge,this is the first work that studies and demonstrates the effectiveness of offline pre-trained models in terms of sample efficiency and generalizability enhancements for MARL.展开更多
The power density of axial piston pumps can benefit greatly from increased rotational speeds.However,the maximum rotational speed of axial piston machines is limited by the cavitation phenomenon for a given volumetric...The power density of axial piston pumps can benefit greatly from increased rotational speeds.However,the maximum rotational speed of axial piston machines is limited by the cavitation phenomenon for a given volumetric displacement.This paper presents a scaling law derived from an analytical cavitation model to estimate the speed limitations for the same series of axial piston pumps.The cavitation model is experimentally verified using a high-speed axial piston pump,and the scaling law is validated with open specification data in product brochures.Results show that the speed limitation is approximately proportional to the square root of the inlet pressure and inversely proportional to the cube root of volumetric displacement.Furthermore,a characteristic constant is defined based on the presented scaling law.This constant can represent the comprehensive capacity of axial piston pumps free from cavitation.展开更多
Background:Tri-ponderal mass index(TMI)has been reported to be a more accurate estimate of body fat than body mass index(BMI).This study aims to compare the effectiveness of TMI and BMI in identifying hypertension,dys...Background:Tri-ponderal mass index(TMI)has been reported to be a more accurate estimate of body fat than body mass index(BMI).This study aims to compare the effectiveness of TMI and BMI in identifying hypertension,dyslipidemia,impaired fasting glucose(IFG),abdominal obesity,and clustered cardio-metabolic risk factors(CMRFs)in 3-to 17-year-old children.Methods:A total of 1587 children aged 3 to 17 years were included.Logistic regression was used to evaluate correlations between BMI and TMI.Area under the curves(AUCs)were used to compare discriminative capability among indicators.BMI was converted to BMI-z scores,and accuracy was compared by false-positive rate,false-negative rate,and total misclassification rate.Results:Among children aged 3 to 17 years,the mean TMI was 13.57±2.50 kg/m 3 for boys and 13.3±2.33 kg/m 3 for girls.Odds ratios(ORs)of TMI for hypertension,dyslipidemia,abdominal obesity,and clustered CMRFs ranged from 1.13 to 3.15,higher than BMI,whose ORs ranged from 1.08 to 2.98.AUCs showed similar ability of TMI(AUC:0.83)and BMI(AUC:0.85)in identifying clustered CMRFs.For abdominal obesity and hypertension,the AUC of TMI was 0.92 and 0.64,respectively,which was significantly better than that of BMI,0.85 and 0.61.AUCs of TMI for dyslipidemia and IFG were 0.58 and 0.49.When 85th and 95th of TMI were set as thresholds,total misclassification rates of TMI for clustered CMRFs ranged from 6.5%to 16.4%,which was not significantly different from that of BMI-z scores standardized according to World Health Organization criteria.Conclusions:TMI was found to have equal or even better effectiveness in comparison with BMI in identifying hypertension,abdominal obesity,and clustered CMRFs TMI was more stable than BMI in 3-to 17-year-old children,while it failed to identify dyslipidemia and IFG.It is worth considering the use of TMI for screening CMRFs in children and adolescents.展开更多
基金supported by the National Natural Science Foundation of China(grant numbers 42307133 and 82073573)the Young Elite Scientists Sponsorship Program by CAST(grant number 2023QNRC001)the Beijing Education Science Planning Project(grant number ACEA24118).
文摘Objective To analyze trends in the depressive disorder burden across BRICS Plus countries and their associations with age,period,and cohort effects.Methods Prevalence,incidence,and disability-adjusted life years(DALYs)estimates of the depressive disorder burden were obtained from the Global Burden of Disease Study,2021.This study further assessed the period and cohort effects on depressive disorders from 1992 to 2021 using an age-periodcohort model.Results In 2021,152.6 million people had depressive disorders across the BRICS Plus countries,showing an increase of 85.6%from 1990,which caused 23.7 million DALYs.The age-standardized prevalence rate(ASPR)of depressive disorders declined by 4.1%from 1990 to 2019,followed by a substantial increase(11.3%)from 2019 to 2021.Furthermore,period and cohort effects showed that the depressive disorder burden increased over time and in the recent birth cohort.Meanwhile,the depressive disorder burden increased among adolescents,young adults,and older adults in the BRICS Plus group.Ultimately,projections for 2050 suggest a 150.0%increase in the ASPR.Conclusion This study revealed a heavy depressive disorder burden across BRICS Plus countries,especially among adolescents,young adults,and older adults.This highlights the need to strengthen specific public health strategies and policies targeting populations with different priorities.
文摘Multi-stage Mesozoic thrust-nappe and extensional structures are distributed in the east segment of the Southeast Yangtze Block situated in the junction region of Zhejiang-Jiangxi-Anhui provinces. The features and genetic mechanism of the deformations were analyzed after a detailed field observation of their distribution, geometry, and kinematics. In addition, the time sequences of the thrust and extensional structures were determined by combining the results of the comparative analysis with the chronological evidence of strata and magmatic rocks cut by a fault or formed after a fault according to field facts. This study identified three stages of the nappe structures and at least two stages of the extensional structures during the Mesozoic. The geotectonic setting of the nappe and extensional structures was considered to be related to the different geodynamics in the study area including the Early Mesozoic geological event, i.e., N-S compression, forming Lantian fault, etc.;the Late Mesozoic flat-slab subduction, forming Xiaoxi thrust fault and tectonic window;and the roll-back of the paleoPacific Plate, forming extensional structures like basin marginal fault;the last compression, forming Wucheng-Shenxian fault. These findings provide additional evidence for remodeling the tectonic and geodynamic evolution of Southeast China.
基金Linghui Meng was supported in part by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA27030300)Haifeng Zhang was supported in part by the National Natural Science Foundation of China(No.62206289).
文摘Offline reinforcement learning leverages previously collected offline datasets to learn optimal policies with no necessity to access the real environment.Such a paradigm is also desirable for multi-agent reinforcement learning(MARL)tasks,given the combinatorially increased interactions among agents and with the environment.However,in MARL,the paradigm of offline pre-training with online fine-tuning has not been studied,nor even datasets or benchmarks for offline MARL research are available.In this paper,we facilitate the research by providing large-scale datasets and using them to examine the usage of the decision transformer in the context of MARL.We investigate the generalization of MARL offline pre-training in the following three aspects:1)between single agents and multiple agents,2)from offline pretraining to online fine tuning,and 3)to that of multiple downstream tasks with few-shot and zero-shot capabilities.We start by introducing the first offline MARL dataset with diverse quality levels based on the StarCraftII environment,and then propose the novel architecture of multi-agent decision transformer(MADT)for effective offline learning.MADT leverages the transformer′s modelling ability for sequence modelling and integrates it seamlessly with both offline and online MARL tasks.A significant benefit of MADT is that it learns generalizable policies that can transfer between different types of agents under different task scenarios.On the StarCraft II offline dataset,MADT outperforms the state-of-the-art offline reinforcement learning(RL)baselines,including BCQ and CQL.When applied to online tasks,the pre-trained MADT significantly improves sample efficiency and enjoys strong performance in both few-short and zero-shot cases.To the best of our knowledge,this is the first work that studies and demonstrates the effectiveness of offline pre-trained models in terms of sample efficiency and generalizability enhancements for MARL.
基金supported by the China National Postdoctoral Program for Innovative Talents(Grant No.BX20200210)the China Postdoctoral Science Foundation(Grant No.2019M660086)the Common Technology for Equipment Pre-research Project(Grant No.41402050202).
文摘The power density of axial piston pumps can benefit greatly from increased rotational speeds.However,the maximum rotational speed of axial piston machines is limited by the cavitation phenomenon for a given volumetric displacement.This paper presents a scaling law derived from an analytical cavitation model to estimate the speed limitations for the same series of axial piston pumps.The cavitation model is experimentally verified using a high-speed axial piston pump,and the scaling law is validated with open specification data in product brochures.Results show that the speed limitation is approximately proportional to the square root of the inlet pressure and inversely proportional to the cube root of volumetric displacement.Furthermore,a characteristic constant is defined based on the presented scaling law.This constant can represent the comprehensive capacity of axial piston pumps free from cavitation.
基金The Special Fund of the Pediatric Medical Coordinated Development Center of Beijing Hospitals Authority(No.XTCX201813)
文摘Background:Tri-ponderal mass index(TMI)has been reported to be a more accurate estimate of body fat than body mass index(BMI).This study aims to compare the effectiveness of TMI and BMI in identifying hypertension,dyslipidemia,impaired fasting glucose(IFG),abdominal obesity,and clustered cardio-metabolic risk factors(CMRFs)in 3-to 17-year-old children.Methods:A total of 1587 children aged 3 to 17 years were included.Logistic regression was used to evaluate correlations between BMI and TMI.Area under the curves(AUCs)were used to compare discriminative capability among indicators.BMI was converted to BMI-z scores,and accuracy was compared by false-positive rate,false-negative rate,and total misclassification rate.Results:Among children aged 3 to 17 years,the mean TMI was 13.57±2.50 kg/m 3 for boys and 13.3±2.33 kg/m 3 for girls.Odds ratios(ORs)of TMI for hypertension,dyslipidemia,abdominal obesity,and clustered CMRFs ranged from 1.13 to 3.15,higher than BMI,whose ORs ranged from 1.08 to 2.98.AUCs showed similar ability of TMI(AUC:0.83)and BMI(AUC:0.85)in identifying clustered CMRFs.For abdominal obesity and hypertension,the AUC of TMI was 0.92 and 0.64,respectively,which was significantly better than that of BMI,0.85 and 0.61.AUCs of TMI for dyslipidemia and IFG were 0.58 and 0.49.When 85th and 95th of TMI were set as thresholds,total misclassification rates of TMI for clustered CMRFs ranged from 6.5%to 16.4%,which was not significantly different from that of BMI-z scores standardized according to World Health Organization criteria.Conclusions:TMI was found to have equal or even better effectiveness in comparison with BMI in identifying hypertension,abdominal obesity,and clustered CMRFs TMI was more stable than BMI in 3-to 17-year-old children,while it failed to identify dyslipidemia and IFG.It is worth considering the use of TMI for screening CMRFs in children and adolescents.
