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1.
Andes Pediatr ; 92(6): 954-962, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35506809

RESUMEN

The Surviving Sepsis Campaign International Guidelines for the Management of Septic Shock and Sepsis-associated Organ Dysfunction in Children was released in 2020 and is intended for use in all global settings that care for children with sepsis. However, practitioners managing children with sep sis in resource-limited settings (RLS) face several challenges and disease patterns not experienced by those in resource-rich settings. Based upon our collective experience from RLS, we aimed to reflect on the difficulties of implementing the international guidelines. We believe there is an urgent need for more evidence from RLS on feasible, efficacious approaches to the management of sepsis and septic shock that could be included in future context-specific guidelines.


Asunto(s)
Sepsis , Choque Séptico , Niño , Cuidados Críticos , Cabeza , Humanos , Organizaciones , Sepsis/diagnóstico , Sepsis/terapia , Choque Séptico/diagnóstico , Choque Séptico/terapia
2.
J Crit Care ; 42: 355-359, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29157660

RESUMEN

Tropical diseases are those that occur primarily or solely in the tropics, and as such include infectious diseases that are particularly prevalent in hot, humid conditions. The incidence of encephalitis in tropical countries is reported to be as high as 6.34/100,000/year. The term encephalitis implies inflammation of the brain and includes the presence of encephalopathy with two and more of the following features: fever, seizures and/or focal neurological findings; a cerebrospinal fluid pleocytosis; electroencephalographic findings or abnormal neuroimaging suggestive of encephalitis. Transverse myelitis (TM) is an inflammation of the spinal cord which has a wide variety of clinical presentations depending on the degree (severity of myelin and neuronal injury) and site of spinal cord involvement. In the present article we discuss the various forms of tropical, viral encephalitides and myelitis and the diagnosis and management.


Asunto(s)
Cuidados Críticos/normas , Encefalitis/diagnóstico , Unidades de Cuidados Intensivos/normas , Mielitis Transversa/diagnóstico , Evaluación de Resultado en la Atención de Salud , Comités Consultivos , Cuidados Críticos/economía , Países en Desarrollo , Encefalitis/terapia , Humanos , Unidades de Cuidados Intensivos/economía , Área sin Atención Médica , Mielitis Transversa/terapia , Convulsiones , Sociedades Médicas , Medicina Tropical
3.
Microb Ecol ; 68(2): 284-98, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24691848

RESUMEN

Tropical peatlands represent globally important carbon sinks with a unique biodiversity and are currently threatened by climate change and human activities. It is now imperative that proxy methods are developed to understand the ecohydrological dynamics of these systems and for testing peatland development models. Testate amoebae have been used as environmental indicators in ecological and palaeoecological studies of peatlands, primarily in ombrotrophic Sphagnum-dominated peatlands in the mid- and high-latitudes. We present the first ecological analysis of testate amoebae in a tropical peatland, a nutrient-poor domed bog in western (Peruvian) Amazonia. Litter samples were collected from different hydrological microforms (hummock to pool) along a transect from the edge to the interior of the peatland. We recorded 47 taxa from 21 genera. The most common taxa are Cryptodifflugia oviformis, Euglypha rotunda type, Phryganella acropodia, Pseudodifflugia fulva type and Trinema lineare. One species found only in the southern hemisphere, Argynnia spicata, is present. Arcella spp., Centropyxis aculeata and Lesqueresia spiralis are indicators of pools containing standing water. Canonical correspondence analysis and non-metric multidimensional scaling illustrate that water table depth is a significant control on the distribution of testate amoebae, similar to the results from mid- and high-latitude peatlands. A transfer function model for water table based on weighted averaging partial least-squares (WAPLS) regression is presented and performs well under cross-validation (r(2)(apparent)= 0.76, RMSE = 4.29; r(2)(jack)= 0.68, RMSEP =5.18). The transfer function was applied to a 1-m peat core, and sample-specific reconstruction errors were generated using bootstrapping. The reconstruction generally suggests near-surface water tables over the last 3,000 years, with a shift to drier conditions at c. cal. 1218-1273 AD.


Asunto(s)
Amoeba/crecimiento & desarrollo , Sphagnopsida/microbiología , Microbiología del Agua , Humedales , Amoeba/clasificación , Amoeba/aislamiento & purificación , Monitoreo del Ambiente , Agua Subterránea , Hidrología , Modelos Teóricos , Perú , Dinámica Poblacional , Suelo
4.
Biol Rev Camb Philos Soc ; 86(2): 457-74, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20849493

RESUMEN

Developing high-quality scientific research will be most effective if research communities with diverse skills and interests are able to share information and knowledge, are aware of the major challenges across disciplines, and can exploit economies of scale to provide robust answers and better inform policy. We evaluate opportunities and challenges facing the development of a more interactive research environment by developing an interdisciplinary synthesis of research on a single geographic region. We focus on the Amazon as it is of enormous regional and global environmental importance and faces a highly uncertain future. To take stock of existing knowledge and provide a framework for analysis we present a set of mini-reviews from fourteen different areas of research, encompassing taxonomy, biodiversity, biogeography, vegetation dynamics, landscape ecology, earth-atmosphere interactions, ecosystem processes, fire, deforestation dynamics, hydrology, hunting, conservation planning, livelihoods, and payments for ecosystem services. Each review highlights the current state of knowledge and identifies research priorities, including major challenges and opportunities. We show that while substantial progress is being made across many areas of scientific research, our understanding of specific issues is often dependent on knowledge from other disciplines. Accelerating the acquisition of reliable and contextualized knowledge about the fate of complex pristine and modified ecosystems is partly dependent on our ability to exploit economies of scale in shared resources and technical expertise, recognise and make explicit interconnections and feedbacks among sub-disciplines, increase the temporal and spatial scale of existing studies, and improve the dissemination of scientific findings to policy makers and society at large. Enhancing interaction among research efforts is vital if we are to make the most of limited funds and overcome the challenges posed by addressing large-scale interdisciplinary questions. Bringing together a diverse scientific community with a single geographic focus can help increase awareness of research questions both within and among disciplines, and reveal the opportunities that may exist for advancing acquisition of reliable knowledge. This approach could be useful for a variety of globally important scientific questions.


Asunto(s)
Ecosistema , Fenómenos Geológicos , Animales , Biodiversidad , Clima , Conservación de los Recursos Naturales , Incendios , Agricultura Forestal , Geografía , Humanos , Plantas/clasificación , Ríos , Sociología , América del Sur , Agua
5.
New Phytol ; 187(3): 631-46, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20659252

RESUMEN

*The rich ecology of tropical forests is intimately tied to their moisture status. Multi-site syntheses can provide a macro-scale view of these linkages and their susceptibility to changing climates. Here, we report pan-tropical and regional-scale analyses of tree vulnerability to drought. *We assembled available data on tropical forest tree stem mortality before, during, and after recent drought events, from 119 monitoring plots in 10 countries concentrated in Amazonia and Borneo. *In most sites, larger trees are disproportionately at risk. At least within Amazonia, low wood density trees are also at greater risk of drought-associated mortality, independent of size. For comparable drought intensities, trees in Borneo are more vulnerable than trees in the Amazon. There is some evidence for lagged impacts of drought, with mortality rates remaining elevated 2 yr after the meteorological event is over. *These findings indicate that repeated droughts would shift the functional composition of tropical forests toward smaller, denser-wooded trees. At very high drought intensities, the linear relationship between tree mortality and moisture stress apparently breaks down, suggesting the existence of moisture stress thresholds beyond which some tropical forests would suffer catastrophic tree mortality.


Asunto(s)
Sequías , Árboles/crecimiento & desarrollo , Clima Tropical , Adaptación Fisiológica , Biomasa , Brasil , Ecosistema , Modelos Biológicos , Tallos de la Planta/crecimiento & desarrollo , Lluvia , Estrés Fisiológico , Factores de Tiempo , Agua , Madera/crecimiento & desarrollo
6.
Science ; 323(5919): 1344-7, 2009 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-19265020

RESUMEN

Amazon forests are a key but poorly understood component of the global carbon cycle. If, as anticipated, they dry this century, they might accelerate climate change through carbon losses and changed surface energy balances. We used records from multiple long-term monitoring plots across Amazonia to assess forest responses to the intense 2005 drought, a possible analog of future events. Affected forest lost biomass, reversing a large long-term carbon sink, with the greatest impacts observed where the dry season was unusually intense. Relative to pre-2005 conditions, forest subjected to a 100-millimeter increase in water deficit lost 5.3 megagrams of aboveground biomass of carbon per hectare. The drought had a total biomass carbon impact of 1.2 to 1.6 petagrams (1.2 x 10(15) to 1.6 x 10(15) grams). Amazon forests therefore appear vulnerable to increasing moisture stress, with the potential for large carbon losses to exert feedback on climate change.


Asunto(s)
Biomasa , Sequías , Ecosistema , Árboles , Atmósfera , Brasil , Carbono , Dióxido de Carbono , Clima , América del Sur , Árboles/crecimiento & desarrollo , Clima Tropical
7.
Biota neotrop. (Online, Ed. port.) ; 8(2)Apr.-June 2008. graf, tab
Artículo en Inglés | LILACS | ID: lil-489025

RESUMEN

The main objective of this paper is to present and discuss the best methods to estimate live above ground biomass in the Atlantic Forest. The methods presented and conclusions are the products of a workshop entitled "Estimation of Biomass and Carbon Stocks: the Case of Atlantic Rain Forest". Aboveground biomass (AGB) in tropical forests is mainly contained in trees. Tree biomass is a function of wood volume, obtained from the diameter and height, architecture and wood density (dry weight per unit volume of fresh wood). It can be quantified by the direct (destructive) or indirect method where the biomass quantification is estimated using mathematical models. The allometric model can be site specific when elaborated to a particular ecosystem or general that can be used in different sites. For the Atlantic Forest, despite the importance of it, there are only two direct measurements of tree biomass, resulting in allometric models specific for this ecosystem. To select one or other of the available models in the literature to estimate AGB it is necessary take into account what is the main question to be answered and the ease with which it is possible to measure the independent variables in the model. Models that present more accurate estimates should be preferred. However, more simple models...


O principal objetivo deste artigo é apresentar e discutir a melhor forma para estimar a biomassa viva acima do solo (BVS) na Mata Atlântica. A biomassa viva acima do solo em florestas tropicais esta contida principalmente nas árvores. A biomassa das árvores é uma função do seu volume de madeira, obtido do diâmetro e da altura, de sua arquitetura e da densidade de sua madeira (peso seco por unidade de volume fresco). Ela pode ser quantificada pelo método direto (destrutivo) ou pelo método indireto onde a quantificação da biomassa é feita através de modelos matemáticos. Os modelos alométricos podem ser específicos para um determinado local, quando elaborado para um ecossistema particular, ou gerais, que podem ser utilizados em para estimar a biomassa em diferentes locais. Para a Mata Atlântica, a despeito de sua importância, existem somente duas medidas diretas de biomassa de árvores, que resultaram em modelos alométricos específicos para essas florestas. Para selecionar um ou outro modelo alométrico para estimar BVS, disponível na literatura, é necessário levar em conta o a questão a ser respondida e a facilidade com a qual é possível medir as variáveis independentes do modelo. Preferencialmente, deve-se utilizar modelos...


Asunto(s)
Árboles/clasificación , Árboles/efectos adversos , Biomasa , Botánica/clasificación , Flora/análisis , Flora/clasificación , Suelo/análisis
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