23 research outputs found
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Conservation in conflict: Illegal drugs versus habitat in the Americas
About the book:
State of the Wild is a biennial series that brings together international conservation experts and writers to discuss emerging issues in the conservation of wildlife and wild places.
Each volume in the series combines evocative writings with a fascinating tour of conservation news highlights and vital statistics from around the world. One-third of each volume focuses on a topic of particular concern to conservationists working to protect wildlife and our last wild places. This 2008–2009 edition considers the integration of wildlife health, ecosystem health, human health, and the health of domestic animals—a “One World–One Health” approach to disease and conservation.
This focus is complemented with essays clustered into sections that address other key issues—conservation of species; conservation of wild places; people, culture, and conservation; and the art and practice of conservation. Essays cover a broad range of topics, from restoring biodiversity on the prairies to mapping the state of the oceans to the conservation impacts of lawlessness and coca cultivation in Colombia. Essay contributions come from people directly involved in on-the-ground conservation efforts and offer a unique and valuable perspective on often-overlooked topics.
State of the Wild’s accessible approach educates a wide range of audiences while at the same time presenting leading-edge scientific overviews of hot topics in conservation. Uniquely structured with magazine-like features up front, conservation news in the middle, and essays from eminent authors and experienced scientists throughout, this landmark series is an essential addition to any environmental bookshelf
Biological Effects of Dispersants and Dispersed Oil in Surface and Deep Ocean Species
Beginning with the use of industrial-strength detergents, dispersing agents have been employed in spill response for decades. The Corexit series of agents in common use today generally consist of non-ionic and/or anionic surfactants in a solvent base designed to enhance miscibility under varying temperature and salinity conditions; cationic surfactants tend to be too toxic for use. While dispersants generally serve to decrease the interfacial surface tension of oil, thus facilitating its weathering under low-energy conditions, their surface-active nature also causes their interaction with cell surfaces – those of single-celled organisms as well as the gills of vertebrates and invertebrates
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Development and Practical Application of Petroleum and Dispersant Interspecies Correlation Models for Aquatic Species
Assessing
the acute toxicity of oil has generally relied on existing
toxicological data for a relatively few standard test species, which
has limited the ability to estimate the impacts of spilled oil on
aquatic communities. Interspecies correlation estimation (ICE) models
were developed for petroleum and dispersant products to facilitate
the prediction of toxicity values to a broader range of species and
to better understand taxonomic differences in species sensitivity.
ICE models are log linear regressions that can be used to estimate
toxicity to a diversity of taxa based on the known toxicity value
for a surrogate tested species. ICE models have only previously been
developed for nonpetroleum chemicals. Petroleum and dispersant ICE
models were statistically significant for 93 and 16 unique surrogate-predicted
species pairs, respectively. These models had adjusted coefficient
of determinations (adj-<i>R</i><sup>2</sup>), square errors
(MSE) and positive slope ranging from 0.29 to 0.99, 0.0002 to 0.311,
and 0.187 to 2.665, respectively. Based on model cross-validation,
predicted toxicity values for most ICE models (>90%) were within
5-fold
of the measured values, with no influence of taxonomic relatedness
on prediction accuracy. A comparison between hazard concentrations
(HC) derived from empirical and ICE-based species sensitivity distributions
(SSDs) showed that HC values were within the same order of magnitude
of each other. These results show that ICE-based SSDs provide a statistically
valid approach to estimating toxicity to a range of petroleum and
dispersant products with applicability to oil spill assessment
Framework for Optimizing Selection of Interspecies Correlation Estimation Models to Address Species Diversity and Toxicity Gaps in an Aquatic Database
The
Chemical Aquatic Fate and Effects (CAFE) database is a tool
that facilitates assessments of accidental chemical releases into
aquatic environments. CAFE contains aquatic toxicity data used in
the development of species sensitivity distributions (SSDs) and the
estimation of hazard concentrations (HCs). For many chemicals, gaps
in species diversity and toxicity data limit the development of SSDs,
which may be filled with Interspecies Correlation Estimation (ICE)
models. Optimization of ICE model selection and integration ICE-predicted
values into CAFE required a multistep process that involved the use
of different types of data to assess their influence on SSDs and HC
estimates. Results from multiple analyses showed that SSDs supplemented
with ICE-predicted values generally produced HC5 estimates that were
within a 3-fold difference of estimates from measured SSDs (58%–82%
of comparisons), but that were often more conservative (63%–76%
of comparisons) and had lower uncertainty (90% of comparisons). ICE
SSDs did not substantially underpredict toxicity (<10% of comparisons)
when compared to estimates from measured SSD. The incorporation of
ICE-predicted values into CAFE allowed the development of >800
new
SSDs, increased diversity in SSDs by an average of 34 species, and
augmented data for priority chemicals involved in accidental chemical
releases