Florida Arsenic Distribution Index: Quantifying the Distribution of Past and Present Arsenic Usage.
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ABSTRACT:
SUBMITTER: Scott-Richardson M
PROVIDER: S-EPMC6427290 | biostudies-literature | 2019 Mar
REPOSITORIES: biostudies-literature
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Project description:Coral-reef degradation is driving global-scale reductions in reef-building capacity and the ecological, geological, and socioeconomic functions it supports. The persistence of those essential functions will depend on whether coral-reef management is able to rebalance the competing processes of reef accretion and erosion. Here, we reconstructed census-based carbonate budgets of 46 reefs throughout the Florida Keys from 1996 to 2019. We evaluated the environmental and ecological drivers of changing budget states and compared historical trends in reef-accretion potential to millennial-scale baselines of accretion from reef cores and future projections with coral restoration. We found that historically, most reefs had positive carbonate budgets, and many had reef-accretion potential comparable to the ~3 mm year-1 average accretion rate during the peak of regional reef building ~7000 years ago; however, declines in reef-building Acropora palmata and Orbicella spp. corals following a series of thermal stress events and coral disease outbreaks resulted in a shift from positive to negative budgets for most reefs in the region. By 2019, only ~15% of reefs had positive net carbonate production. Most of those reefs were in inshore, Lower Keys patch-reef habitats with low water clarity, supporting the hypothesis that environments with naturally low irradiance may provide a refugia from thermal stress. We caution that our estimated carbonate budgets are likely overly optimistic; comparison of reef-accretion potential to measured accretion from reef cores suggests that, by not accounting for the role of nonbiological physical and chemical erosion, census-based carbonate budgets may underestimate total erosion by ~1 mm year-1 (-1.15 kg CaCO3 m-2 year-1 ). Although the present state of Florida's reefs is dire, we demonstrate that the restoration of reef-building corals has the potential to help mitigate declines in reef accretion in some locations, which could allow some key ecosystem functions to be maintained until the threat of global climate change is addressed.
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Project description:Measuring changes of the T cell receptor (TCR) repertoire is important to many fields of medicine. Flow cytometry is a popular technique to study the TCR repertoire, as it quickly provides insight into the TCR-V? usage among well-defined populations of T cells. However, the interpretation of the flow cytometric data remains difficult, and subtle TCR repertoire changes may go undetected. Here, we introduce a novel means for analyzing the flow cytometric data on TCR-V? usage. By applying economic statistics, we calculated the Gini-TCR skewing index from the flow cytometric TCR-V? analysis. The Gini-TCR skewing index, which is a direct measure of TCR-V? distribution among T cells, allowed us to track subtle changes of the TCR repertoire among distinct populations of T cells. Application of the Gini-TCR skewing index to the flow cytometric TCR-V? analysis will greatly help to gain better understanding of the TCR repertoire in health and disease.
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Project description:BackgroundLymphatic filariasis (LF) is one of the neglected tropical diseases targeted for global elimination by 2020 and to guide elimination efforts countries have, in recent years, conducted extensive mapping surveys. Documenting the past and present distribution of LF and its environmental limits is important for a number of reasons. Here, we present an initiative to develop a global atlas of LF and present a new global map of the limits of LF transmission.MethodsWe undertook a systematic search and assembly of prevalence data worldwide and used a suite of environmental and climatic data and boosted regression trees (BRT) modelling to map the transmission limits of LF.ResultsData were identified for 66 of the 72 countries currently endemic and for a further 17 countries where LF is no longer endemic. Our map highlights a restricted and highly heterogeneous distribution in sub-Saharan Africa, with transmission more widespread in West Africa compared to east, central and southern Africa where pockets of transmission occur. Contemporary transmission occurs across much of south and South-east Asia and the Pacific. Interestingly, the risk map reflects environmental conditions suitable for LF transmission across Central and South America, including the southern States of America, although active transmission is only known in a few isolated foci. In countries that have eliminated LF, our predictions of environmental suitability are consistent with historical distribution.ConclusionsThe global distribution of LF is highly heterogeneous and geographically targeted and sustained control will be required to achieve elimination. This first global map can help evaluate the progress of interventions and guide surveillance activities.
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