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1.
Artigo em Inglês | MedCarib | ID: med-17701

RESUMO

Water reservoirs formed by the leaf axils of bromeliads are a highly derived system for nutrient and water capture that also house a diverse fauna of invertebrate specialists. Here we investigate the origin and specificity of bromeliad-associated insects using Copelatinae diving beetles (Dytiscidae). This group is widely distributed in small water bodies throughout tropical forests, but a subset of species encountered in bromeliad tanks is strictly specialized to this habitat. An extensive molecular phylogenetic analysis of Neotropical Copelatinae places these bromeliadicolous species in at least three clades nested within other Copelatus. One lineage is morphologically distinct, and its origin was estimated to reach back to 12-23 million years ago, comparable to the age of the tank habitat itself. Species of this clade in the Atlantic rainforest of southern Brazil and mountain ranges of northern Venezuela and Trinidad show marked phylogeographical structure with up to 8% mtDNA divergence, possibly indicating allopatric speciation. The other two invasions of bromeliad water tanks are more recent, and haplotype distributions within species are best explained by recent expansion into newly formed habitat. Hence, bromeliad tanks create a second stratum of aquatic freshwater habitat independent of that on the ground but affected by parallel processes of species and population diversification at various temporal scales, possibly reflecting the paleoclimatic history of neotropical forests.


Assuntos
Animais , Besouros/fisiologia , Biodiversidade , Bromelia/parasitologia , Ecossistema , Evolução Molecular , Dados de Sequência Molecular , Filogenia , Simbiose , Árvores/parasitologia , Clima Tropical , Trinidad e Tobago
2.
Health policy ; 83(2-3): 196-212, Oct. 2007. tabilus
Artigo em Inglês | MedCarib | ID: med-17706

RESUMO

Mosquito control programs at seven urban sites in Kenya, Egypt, Israel, Costa Rica, and Trinidad are described and compared. Site-specific urban and disease characteristics, organizational diagrams, and strengths, weaknesses, obstacles and threats (SWOT) analysis tools are used to provide a descriptive assessment of each mosquito control program, and provide a comparison of the factors affecting mosquito abatement. The information for SWOT analysis is collected from surveys, focus-group discussions, and personal communication. SWOT analysis identified various issues affecting the efficiency and sustainability of mosquito control operations. The main outcome of our work was the description and comparison of mosquito control operations within the context of each study site's biological, social, political, management, and economic conditions. The issues identified in this study ranged from lack of inter-sector collaboration to operational issues of mosquito control efforts. A lack of sustainable funding for mosquito control was a common problem for most sites. Many unique problems were also identified, which included lack of mosquito surveillance, lack of law enforcement, and negative consequences of human behavior. Identifying common virtues and shortcomings of mosquito control operations is useful in identifying "best practices" for mosquito control operations, thus leading to better control of mosquito biting and mosquito-borne disease transmission.


Assuntos
Animais , Estudo Comparativo , Costa Rica , Ecossistema , Eficiência Organizacional , Egito , Órgãos Governamentais/organização & administração , Pesquisas sobre Atenção à Saúde , Israel , Quênia , Modelos Organizacionais , Controle de Mosquitos/legislação & jurisprudência , Controle de Mosquitos/métodos , Controle de Mosquitos/organização & administração , Dinâmica Populacional , Administração em Saúde Pública , Trinidad e Tobago , Saúde da População Urbana
3.
Chemosphere ; 40(6): 671-8, Mar.,2000.
Artigo em Inglês | MedCarib | ID: med-743

RESUMO

Non-viable eggs of Morelet's crocodile (Crocodylus moreletti) were collected from Gold Botton (GBL) and New River lagoons (NRL) in northern Belize and screened for organochlorine (OC) compounds using gas chromatography (GC) with electron capture detection (ECD). All egg samples from both lagoons (n=24) tested positive for one or more OCs. Primary contaminants were p,p-DDE and methoxychlor, detected in 100 percent and 29 percent of the eggs examined, respectively. Concentrations of individual OC contaminants ranged from 1 ppb (ng chemical/g egg). Total concentrations of OCs (sum of all OCs) for one egg collected from a nest at GBL reached as high as 0.7 ppm. Sediment samples from both lagoons also tested positive for OCs (lindane, aldrin, methoxychlor, heptachlor epoxide, p, p-DDT, among others). Nest media (soil and plant material) collected from crocodile nests at GBL were positive for p, p-DDT, methoxychlor, aldrin, endosulfan II, and endrin aldehyde. Based on the 24 egg samples analyzed to date, crocodiles from both lagoons are being exposed to OCs. Such exposure may present a health threat to populations of crocodiles in Central America. (AU)


Assuntos
21003 , Feminino , Jacarés e Crocodilos , Ovos , Poluentes Ambientais/análise , Inseticidas Organoclorados/análise , Praguicidas/análise , Belize , DDT/análise , DDT/metabolismo , Ecossistema , Endossulfano/análise , Endrin/análise , Sedimentos Geológicos , Heptacloro/análise , Hexaclorocicloexano/análise , Metoxicloro/análise
4.
Science ; 287(5454): 857-9, Feb. 2000.
Artigo em Inglês | MedCarib | ID: med-863

RESUMO

Most marine populations are thought to be well connected via long-distance dispersal of larval stages. Eulerian and Lagrangian flow models, coupled with linear mortality estimates, were used to examine this assumption. The findings show that when simple advection models are used, larval exchange rates may be overestimated; such simplistic models fail to account for a decrease of up to nine orders of magnitude in larval concentrations resulting from diffusion and mortality. The alternative process of larval retention near local populations is shown to exist and may be of great importance in the maintenance of marine population structure and management of coastal marine resources.(Au)


Assuntos
21003 , Ecossistema , Peixes/fisiologia , Água do Mar , Barbados , Simulação por Computador , Geografia , Larva/fisiologia , Biologia Marinha , Modelos Biológicos , Dinâmica Populacional
5.
West Indian med. j ; 47(Suppl. 4): 25-7, Dec. 1998.
Artigo em Inglês | MedCarib | ID: med-1292

RESUMO

Environmental health is the ecological balance that must exist between man and his environment in order to ensure his well being. This paper describes the range of environmental hazards (physical, biological, chemical and social) and discusses the differences in level and quality of environmental health programmes between developed and developing countries. The hazards are the same in both realms; the difference is in the level of advocacy and, thus, the demand for implementation of sound environmental health policies and practices. Issues which developing countries need to address to improve environmental health management are outlined.(AU)


Assuntos
Humanos , Saúde Ambiental , Países em Desenvolvimento , Substâncias Perigosas , Defesa do Consumidor , Países Desenvolvidos , Ecossistema , Poluição Ambiental , Política de Saúde , Prioridades em Saúde , Nível de Saúde , Jamaica , Saúde Pública , Fatores Socioeconômicos
6.
Anon.
Washington; Pan American Health Organisation; 1996. xvii,229 p. maps, tab.
Monografia em Inglês | MedCarib | ID: med-16471

RESUMO

This publication, "Emerging Connections" for short, explores the scientific and technological alternatives; economic prospects; and environmental, legal, political, sociocultural, and institutional consequences and implications for countries at different stages of scientific and economic development, with different capabilities, and different natural resource endowments. Finally, it discusses whether Latin America's biodiversity will, in fact, become the region's new competitive advantage (Introd)


Assuntos
Humanos , Saúde Pública , Região do Caribe , Ecossistema , Biotecnologia/tendências , Agricultura/tendências , Modelos Biológicos , Farmacognosia , América Latina , Desenvolvimento Sustentável
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