3,688 research outputs found

    Lag effects in the impacts of mass coral bleaching on coral reef fish, fisheries, and ecosystems

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    Recent episodes of coral bleaching have led to wide-scale loss of reef corals and raised concerns over the effectiveness of existing conservation and management efforts. The 1998 bleaching event was most severe in the western Indian Ocean, where coral declined by up to 90% in some locations. Using fisheries-independent data, we assessed the long-term impacts of this event on fishery target species in the Seychelles, the overall size structure of the fish assemblage, and the effectiveness of two marine protected areas (MPAs) in protecting fish communities. The biomass of fished species above the size retained in fish traps changed little between 1994 and 2005, indicating no current effect on fishery yields. Biomass remained higher in MPAs, indicating they were effective in protecting fish stocks. Nevertheless, the size structure of the fish communities, as described with size-spectra analysis, changed in both fished areas and MPAs, with a decline in smaller fish (<30 cm) and an increase in larger fish (>45 cm). We believe this represents a time-lag response to a reduction in reef structural complexity brought about because fishes are being lost through natural mortality and fishing, and are not being replaced by juveniles. This effect is expected to be greater in terms of fisheries productivity and, because congruent patterns are observed for herbivores, suggests that MPAs do not offer coral reefs long-term resilience to bleaching events. Corallivores and planktivores declined strikingly in abundance, particularly in MPAs, and this decline was associated with a similar pattern of decline in their preferred corals. We suggest that climate-mediated disturbances, such as coral bleaching, be at the fore of conservation planning for coral reefs.\u

    Restoration of peatlands and greenhouse gas balances

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    In this chapter the impact of peatland restoration on greenhouse gas fluxes is discussed based on a literature review. Casestudies are presented covering different peatland types, different regions and different starting conditions

    Making information measurement meaningful: the United Nations’ Sustainable Development Goals and the Social and Human Capital Protocol

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    Drucker’s saying that “What gets measured gets managed” is examined in the context of corporate social responsibility. The United Nations’ Sustainable Development Goals have encouraged sustainability reporting, and a reporting tool, the Social and Human Capital Protocol, has been developed to assist measurement and provide information to support the achievement of sustainability. This information should be valid and reliable; however, it is not easy to measure social and human capital factors. Additionally, companies use a large number of methodologies and indicators that are difficult to compare, and they may sometimes only present positive outcomes as a form of greenwashing. This lack of full transparency and comparability with other companies has the potential to discredit their reports, thereby supporting the claims of climate change deniers, free-market idealogues and conspiracy theorists who often use social media to spread their perspectives. This paper will describe the development of environmental reporting and CSR, discuss the natural capital protocol, and assess the extent to which the Social and Human Capital Protocol is able to fulfil its purpose of providing SMART objective measurements. It is the first academic article to provide a detailed examination of the Social and Human Capital Protocol

    Drug-induced chest pain and myocardial infarction. Reports to a national centre and review of the literature

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    Objectives: To analyse reports of drug-induced myocardial infarction and chest pain sent to a national reporting centre. To review which drugs were suspected of exhibiting these adverse events and what mechanisms were involved. Methods: During the 20-year period 1975 through 1994, a total of 19,141 reports on adverse reactions to drugs were received by the Netherlands Centre for Monitoring of Adverse Reactions to Drugs. Of these 19 141 reports, 220 (1.1%) were concerned with drug-induced chest pain or myocardial infarction. After excluding reports in which the causal relationship was unlikely, poorly documented reports and reports on cases of overdosage, 183 reports (84%) were analysed. Results: There were 130 reports (71%) of drug-induced chest pain and 53 reports (29%) of drug-induced myocardial infarction. A total of 104 reports concerned females (57%). The most frequently reported suspected drugs were the antimigraine drug sumatriptan (33 reports, 4 concerning myocardial inf

    Impact of chloride on uranium(VI) speciation in acidic sulfate ion exchange systems: Towards seawater-tolerant mineral processing circuits

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    Using X-ray absorption spectroscopy, we have identified the mechanism by which chloride impacts the extraction of U(VI) by a weak base anion exchange resin from acidic sulfate solutions. The amount of chloride present affects U(VI) speciation both in the feed solutions and adsorbed by the resin, and we find three distinct U(VI) species taken up by the resin across the salinity gradient, directly corresponding to changes in levels of U(VI) extraction. These findings are integral to the effective design of mineral processing circuits incorporating seawater—a cheaper and more sustainable water source than fresh water

    Investigating hookworm genomes by comparative analysis of two Ancylostoma species

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    Background Hookworms, infecting over one billion people, are the mostly closely related major human parasites to the model nematode Caenorhabditis elegans. Applying genomics techniques to these species, we analyzed 3,840 and 3,149 genes from Ancylostoma caninum and A. ceylanicum. Results Transcripts originated from libraries representing infective L3 larva, stimulated L3, arrested L3, and adults. Most genes are represented in single stages including abundant transcripts like hsp-20 in infective L3 and vit-3 in adults. Over 80% of the genes have homologs in C. elegans, and nearly 30% of these were with observable RNA interference phenotypes. Homologies were identified to nematode-specific and clade V specific gene families. To study the evolution of hookworm genes, 574 A. caninum / A. ceylanicum orthologs were identified, all of which were found to be under purifying selection with distribution ratios of nonsynonymous to synonymous amino acid substitutions similar to that reported for C. elegans / C. briggsae orthologs. The phylogenetic distance between A. caninum and A. ceylanicum is almost identical to that for C. elegans / C. briggsae. Conclusion The genes discovered should substantially accelerate research toward better understanding of the parasites' basic biology as well as new therapies including vaccines and novel anthelmintics

    Nuclear Flow Excitation Function

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    We consider the dependence of collective flow on the nuclear surface thickness in a Boltzmann--Uehling--Uhlenbeck transport model of heavy ion collisions. Well defined surfaces are introduced by giving test particles a Gaussian density profile of constant width. Zeros of the flow excitation function are as much influenced by the surface thickness as the nuclear equation of state, and the dependence of this effect is understood in terms of a simple potential scattering model. Realistic calculations must also take into account medium effects for the nucleon--nucleon cross section, and impact parameter averaging. We find that balance energy scales with the mass number as AyA^{-y}, where yy has a numerical value between 0.35 and 0.5, depending on the assumptions about the in-medium nucleon-nucleon cross section.Comment: 11 pages (LaTeX), 7 figures (not included), MSUCL-884, WSU-NP-93-

    Prévalence en anticorps contre le virus de la fièvre de la vallée du Rift chez les petits ruminants du Sénégal

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    Une enquête de prévalence en anticorps contre le virus de la fièvre de la Vallée du Rift a été réalisée sur un échantillon représentatif du cheptel ovin et caprin du Sénégal. La répartition des anticorps montre l'état enzootique de la fièvre de la vallée du Rift dans ce cheptel. Les prévalences en anticorps chez les ovins et caprins sont comparables mais réparties de façon très hétérogène selon les zones étudiées (Résumé d'auteur

    Deconvolution of conformational exchange from Raman spectra of aqueous RNA nucleosides

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    Ribonucleic acids (RNAs) are key to the central dogma of molecular biology. While Raman spectroscopy holds great potential for studying RNA conformational dynamics, current computational Raman prediction and assignment methods are limited in terms of system size and inclusion of conformational exchange. Here, a framework is presented that predicts Raman spectra using mixtures of sub-spectra corresponding to major conformers calculated using classical and ab initio molecular dynamics. Experimental optimization allowed purines and pyrimidines to be characterized as predominantly syn and anti, respectively, and ribose into exchange between equivalent south and north populations. These measurements are in excellent agreement with Raman spectroscopy of ribonucleosides, and previous experimental and computational results. This framework provides a measure of ribonucleoside solution populations and conformational exchange in RNA subunits. It complements other experimental techniques and could be extended to other molecules, such as proteins and carbohydrates, enabling biological insights and providing a new analytical tool
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