1,844 research outputs found

    Nitrogen and phosphorus additions negatively affect tree species diversity in tropical forest regrowth trajectories

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    Nutrient enrichment is increasingly affecting many tropical ecosystems, but there is no information on how this affects tree biodiversity. To examine dynamics in vegetation structure and tree species biomass and diversity, we annually remeasured tree species before and for six years after repeated additions of nitrogen (N) and phosphorus (P) in permanent plots of abandoned pasture in Amazonia. Nitrogen and, to a lesser extent, phosphorus addition shifted growth among woody species. Nitrogen stimulated growth of two common pioneer tree species and one common tree species adaptable to both high-and low-light environments, while P stimulated growth only of the dominant pioneer tree Rollinia exsucca (Annonaceae). Overall, N or P addition reduced tree assemblage evenness and delayed tree species accrual over time, likely due to competitive monopolization of other resources by the few tree species responding to nutrient enrichment with enhanced establishment and/or growth rates. Absolute tree growth rates were elevated for two years after nutrient addition. However, nutrient-induced shifts in relative tree species growth and reduced assemblage evenness persisted for more than three years after nutrient addition, favoring two nutrient-responsive pioneers and one early-secondary tree species. Surprisingly, N + P effects on tree biomass and species diversity were consistently weaker than N-only and P-only effects, because grass biomass increased dramatically in response to N + P addition. The resulting intensified competition probably prevented an expected positive N + P synergy in the tree assemblage. Thus, N or P enrichment may favor unknown tree functional response types, reduce the diversity of coexisting species, and delay species accrual during structurally and functionally complex tropical rainforest secondary succession

    Utilização do cultivo in vitro de folĂ­culos prĂ©-antrais suĂ­nos inclusos em tecido ovariano (in situ) como modelo de avaliação da eficiĂȘncia de medicamentos homeopĂĄticos na foliculogĂȘnese inicial

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    Este trabalho teve por objetivo avaliar o efeito dos medicamentos homeopĂĄticos (Pulsatilla nigricans e hormĂŽnio folĂ­culo estimulante homeopĂĄtico - FSH) e um complexo homeopĂĄtico (Bos Stress Fertilis) na foliculogĂȘnese inicial, utilizando o cultivo in vitro de folĂ­culos prĂ©-antrais suĂ­nos como modelo in vitro. Para tanto, fragmentos ovarianos foram cultivados por um ou sete dias em α-MEM+ na ausĂȘncia (controle cultivado) ou presença de FSH homeopĂĄtico (6 cH), Pulsatilla (6 CH), Bos Stress Fertilis (6 CH), ĂĄlcool cereal (50% - v/v) ou FSH recombinante (50 ng/ml) adicionados diariamente. Os fragmentos ovarianos nĂŁo cultivados (controle fresco) ou cultivados por um e sete dias foram processados para histologia clĂĄssica. Somente o composto homeopĂĄtico Bos Stress Fertilis foi eficiente em manter o percentual de sobrevivĂȘncia folicular apĂłs sete dias de cultivo semelhante ao controle nĂŁo cultivado e α-MEM+. Em relação ao crescimento folicular, somente a adição de FSH homeopĂĄtico aumentou o diĂąmetro folicular quando comparado ao controle nĂŁo cultivado e α-MEM+ apĂłs um dia de cultivo. Dessa forma, pode-se concluir que a adição dos medicamentos homeopĂĄticos Bos Stress fertilis e FSH homeopĂĄtico (6 CH) melhoraram, respectivamente, a sobrevivĂȘncia e o crescimento in vitro de folĂ­culos prĂ©-antrais suĂ­nos inclusos em fragmentos de tecido ovariano. Palavras-chave: FolĂ­culo prĂ©-antral; FSH; Fomeopatia; OvĂĄrio; SuĂ­n

    Risk factors associated with death in Brazilian children with severe dengue: a case-control study

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    Objective: The purpose of this case-control study was to evaluate risk factors associated with death in children with severe dengue. Methods: The clinical condition of hospitalized patients with severe dengue who died (cases, n = 18) was compared with that of hospitalized patients with severe dengue who survived (controls, n = 77). The inclusion criteria for this study were age under 13 years; hospital admission in São Luis, northeastern Brazil; and laboratory-confirmed diagnosis of dengue. Results: Severe bleeding (hemoptysis), a defining criterion for dengue severity, was the factor most strongly associated with death in our study. We also found that epistaxis and persistent vomiting, both included as warning signs in the World Health Organization (WHO) classification of dengue, were strongly associated with death. No significant association was observed between any of the laboratory findings and death. Conclusions: The finding that epistaxis and persistent vomiting were also associated with death in children with severe dengue was unexpected and deserves to be explored in future studies. Because intensive care units are often limited in resource-poor settings, any information that can help to distinguish patients with severe dengue with a higher risk to progress to death may be crucial

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI
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