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BACKGROUND: Studies across the globe generally reported increased mortality risks associated with particulate matter with aerodynamic diameter ≤2.5 μm (PM2.5) exposure with large heterogeneity in the magnitude of reported associations and the shape of concentration-response functions (CRFs). We aimed to evaluate the impact of key study design factors (including confounders, applied exposure model, population age, and outcome definition) on PM2.5 effect estimates by harmonizing analyses on three previously published large studies in Canada [Mortality-Air Pollution Associations in Low Exposure Environments (MAPLE), 1991-2016], the United States (Medicare, 2000-2016), and Europe [Effects of Low-Level Air Pollution: A Study in Europe (ELAPSE), 2000-2016] as much as possible. METHODS: We harmonized the study populations to individuals 65+ years of age, applied the same satellite-derived PM2.5 exposure estimates, and selected the same sets of potential confounders and the same outcome. We evaluated whether differences in previously published effect estimates across cohorts were reduced after harmonization among these factors. Additional analyses were conducted to assess the influence of key design features on estimated risks, including adjusted covariates and exposure assessment method. A combined CRF was assessed with meta-analysis based on the extended shape-constrained health impact function (eSCHIF). RESULTS: More than 81 million participants were included, contributing 692 million person-years of follow-up. Hazard ratios and 95% confidence intervals (CIs) for all-cause mortality associated with a 5-μg/m³ increase in PM2.5 were 1.039 (1.032, 1.046) in MAPLE, 1.025 (1.021, 1.029) in Medicare, and 1.041 (1.014, 1.069) in ELAPSE. Applying a harmonized analytical approach marginally reduced difference in the observed associations across the three studies. Magnitude of the association was affected by the adjusted covariates, exposure assessment methodology, age of the population, and marginally by outcome definition. Shape of the CRFs differed across cohorts but generally showed associations down to the lowest observed PM2.5 levels. A common CRF suggested a monotonically increased risk down to the lowest exposure level. [ABSTRACT FROM AUTHOR]

The purpose of this work is to study the principle fluctuation modes of the global stock market, which is regarded as a complex system. It is proposed that the systematic risk can be reflected by the trace calculated from the cross-correlation matrix, and the integrity can be classified into clusters according to the plus-minus signs of the elements of the eigenvectors corresponding to several top largest eigenvalues whose total value accounts for more than 60 percent of the trace. The principle fluctuation modes of 30 stock markets are in the same direction in each year of 2005-2010. According to the classification criteria proposed here, the stock markets of the Americas, Europe and Asia & Oceania are automatically classified into different clusters, while Brazil, Russia and China are separated. [ABSTRACT FROM AUTHOR]

Faced with a global biodiversity crisis, we need to concentrate our collective efforts on safeguarding Key Biodiversity Areas (KBAs), which serve as essential habitats for the world's threatened species. Clarifying the disturbance and protection requirements of KBAs is vital to the global persistence of biodiversity, which is not yet clear. Here, we evaluated the extent and severity of human disturbance in KBAs. Specifically, we analyzed the spatial patterns of disturbance and their potential effects on habitats. Roughly a quarter of terrestrial KBAs are challenged by crop production and urban construction activities, especially in Europe. The mean Human Footprint Index (HFI) for KBAs worldwide is 12.3, indicating a high level of human disturbance. On average, 62 % of each KBA is identified as Human Threatened Areas, signifying intense human impacts on these areas. 57 % of KBAs are subdivided by human disturbance, which can lead to substantial habitat fragmentation and loss of connectivity compared to other forms of disturbance. The halving of mean patch size and the tripling of the perimeter-area ratio for active habitats in KBAs provide evidence of the difficulties faced in conserving these areas. More importantly, increased coverage of Protected Areas fails to reduce HFI in KBAs, indicating some deficiencies in current protection systems. Therefore, we emphasize the importance of focusing on disturbance patterns for more impactful interventions, which potentially offer new pathways to mitigate adverse habitat impacts in post-2020 biodiversity conservation efforts. [Display omitted] • A quarter of KBAs are challenged by crop production and urban construction activities. • An average Human Footprint Index of 12.3 means high human disturbance in KBAs. • 57 % of KBAs are impacted by subdivision-related human disturbance. • A tripling of active habitats' perimeter-area ratio signals a high challenge in KBA protection • A method is explored to identify spatial patterns of human disturbance. [ABSTRACT FROM AUTHOR]