Engagement in outdoor physical activity under ambient fine particulate matter pollution: A risk-benefit analysis

Background:Outdoor physical activity(PA)brings important health benefits,but exposure to polluted air increases health risks.This study aimed to quantify the tradeoff of PA under fine particulate matter(PM_(2.5))air pollution by estimating the optimal PA duration under various pollution levels.Methods:A risk-benefit analysis was performed to estimate the optimal outdoor moderate-intensity PA(MPA)duration under varying PM_(2.5) concentrations.Results:An inverse nonlinear relationship was identified between optimal MPA duration and background PM_(2.5) concentration levels.When background PM_(2.5) concentration increased to 186 μg/m^(3),the optimal outdoor MPA duration decreased to 2.5 h/week,the minimum level recommended by current PA guidelines.When background PM_(2.5) concentration further increased to 235 μg/m^(3),the optimal outdoor MPA duration decreased to 1 h/week.The relationship between optimal MPA duration and background PM_(2.5) concentration levels was stronger when exercising at a location closer to a source of air pollution.Compared to the general adult population,adults aged 60 years and older had substantially steeper curves—the optimal outdoor MPA duration decreased to 2.5 h/week when background PM_(2.5) concentration reached 45 μg/m^(3).Conclusion:The health benefit of outdoor MPA by far outweighs the health risk of PM_(2.5) pollution for the global average urban background concentration(22 μg/m^(3),).This modeling study examined a single type of air pollutant and suffered from measurement errors and estimation uncertainties.Future research should examine other air pollutants and indoor PA,incorporate short-and mid-term health effects of MPA and air pollution into the risk-benefit analysis,and provide estimates specific for high-risk subgroups.

Association of overall survival benefit of radiotherapy with progression-free survival after chemotherapy for diffuse large B-cell lymphoma:A systematic review and meta-analysis

Objective:To evaluate whether improved progression-free survival(PFS)from radiotherapy(RT)translates into an overall survival(OS)benefit for diffuse large B-cell lymphoma(DLBCL).Methods:A systematic literature search identified randomized controlled trials(RCTs)and retrospective studies that compared combined-modality therapy(CMT)with chemotherapy(CT)alone.Weighted regression analyses were used to estimate the correlation between OS and PFS benefits.Cohen’s kappa statistic assessed the consis-tency between DLBCL risk-models and PFS patterns.Furthermore,the benefit trend of RT was analyzed by fitting a linear regression model to the pooled hazard ratio(HR)according to the PFS patterns.Results:For both 7 RCTs and 52 retrospective studies,correlations were found between PFS HR(HRPFS)and OS HR(HROS)at trial level(r=0.639-0.876),and between PFS and OS rates at treatment-arm level,regardless of CT regimens(r=0.882-0.964).Incorporating RT into CT increased about 18%of PFS,and revealed a different OS benefit profile.Patients were stratified into four CT-generated PFS patterns(>80%,>60-80%,>40-60%,and≤40%),which was consistent with risk-stratified subgroups(kappa>0.6).Absolute gain in OS from RT ranged from≤5%at PFS>80%to about 21%at PFS≤40%,with pooled HROS from 0.70(95%CI,0.51-0.97)to 0.48(95%CI,0.36-0.63)after rituximab-based CT.The OS benefit of RT was predominant in intermediate-and high-risk patients with PFS≤80%.Conclusion:We demonstrated a varied OS benefit profile of RT to inform treatment decisions and clinical trial design.

New challenges for optimal design of nearly/net zero energy buildings under post-occupancy performance-based design standards and a risk-benefit based solution

One of the challenges in construction of nearly and net ZEBs is how to truly achieve the nearly and net energy goals after building occupancy.Traditional building design standards and practices are mostly based on design performance evaluation,but practices show that many designed nearly/net ZEBs failed to achieve the energy goals after building occupancy.To facilitate the practical achievement of nearly and net ZEBs,recently most of the newly-released ZEB design standards have turned to post-occupancy performance evaluation,posing great challenges to nearly and net ZEB design.However,the detailed challenges have not be comprehensively investigated,and effective optimal design methods which can facilitate the achievement of nearly and net ZEBs under these standards are still absent.In this study,new challenges of nearly and net ZEB design under the post-occupancy performance-based design standards are fully investigated,and a risk-benefit based optimal design method is proposed to facilitate the achievement of nearly and net ZEBs under these standards.The newly-released ZEB standard in China is taken as an example to investigate the challenges and test the proposed method.Results show that nearly and net ZEBs designed using conventional design method have high risk in achieving energy goals under these standards due to high risk in satisfying the requirement regarding non-renewable primary energy consumption after building occupancy.The proposed design method is effective to facilitate achieving energy goals under these standards based on the risk that decision-makers would like to take.

保险公司破产中保单持有人权益保护机制研究

保险公司破产是保险行业资源优化配置、提升整体竞争力的必然要求。但保险公司破产将对众多保单持有人权益产生不利影响,基于风险收益匹配理论,应予优先保护保单持有人权益。保险公司破产程序划分为破产前置程序和司法破产程序,保单持有人权益保护机制的构建也应以此为界分。在破产前置程序中,保单持有人权益保护间接表现为恢复问题保险公司的经营能力,应构建层层递进的监管体系,设置保险保障基金的提前参与程序。在司法破产程序中,着力于完善"保单转让"、"保单救济"和"优先清偿"规则。