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1.
Biology (Basel) ; 11(11)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36358320

RESUMO

Deep-sea fisheries are of important economic value. Therefore, it is necessary to generate biologically and ecologically based fishing plans to make this fishery sustainable over time. The silver scabbardfish, Lepidopus caudatus, is a worldwide-distributed demersal fish, commercially exploited in the Azores. Despite L. caudatus high landings and discharges in the region, information about its ecology, population structure, biology and fisheries remains little-known. This work analyzed scientific survey and fishery-dependent data from the past 30 years to understand the changes in abundance, spatial distribution and life history of this species. Lepidopus caudatus spatial distribution was associated with depths between 200 and 400 m, close to seamounts and islands, and on sandy bottoms. The size structure varied yearly, and the population was dominated by females (sex ratio, M:F = 0.46:1). Growth rates were between the estimated values in previous studies in the Azores and indicated a slow-grower species (L∞ = 171.62 cm, k = 0.12 year-1, Φ' = 3.52). The abundance indices highlighted a declining tendency, and this result was backed by the high exploitation rate for the fish in the region (E = 0.53). Lack of management measurements and the species' vulnerability could lead to the depletion of this species.

2.
Data Brief ; 37: 107235, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34195310

RESUMO

This dataset contains 2850 photographs of the seafloor in coral communities from Venezuela that were taken during 2017 and 2018. We used a hierarchical experimental design with four random factors representing four different spatial scales: (1) region (hundreds of kilometers), (2) localities (tens of kilometers), (2) reef sites (hundreds of meters) and (3) transects (a couple meters) across the Venezuelan coast. At each site, four 30-m transects were deployed parallel to the coastline, and 15 pictures were taken every other meter at each transect, containing an area of at least 80 × 90cm with enough resolution to identify benthic groups. This dataset covers spatial scales from a few meters to hundreds of kilometers; marine protected areas, and non-protected areas; coastal zones, continental and oceanic islands. These images have the potential to be further used for training researchers in benthic organisms identification, and training artificial intelligence classification algorithms. Also, they represent and updated baseline to perform spatial and temporal comparisons in Venezuela or further studies involving multiple spatial scales in the region.

3.
PeerJ ; 8: e9082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411533

RESUMO

Estimating variability across spatial scales has been a major issue in ecology because the description of patterns in space is extremely valuable to propose specific hypotheses to unveil key processes behind these patterns. This paper aims to estimate the variability of the coral assemblage structure at different spatial scales in order to determine which scales explain the largest variability on ß-diversity. For this, a fully-nested design including a series of hierarchical-random factors encompassing three spatial scales: (1) regions, (2) localities and (3) reefs sites across the Venezuelan territory. The variability among spatial scales was tested with a permutation-based analysis of variance (Permanova) based on Bray-Curtis index. Dispersion in species presence/absence across scales (i.e., ß-diversity) was tested with a PermDisp analysis based on Jaccard's index. We found the highest variability in the coral assemblage structure between sites within localities (Pseudo-F = 5.34; p-value = 0.001, CV = 35.10%). We also found that longitude (Canonical corr = 0.867, p = 0.001) is a better predictor of the coral assemblage structure in Venezuela, than latitude (Canonical corr = 0.552, p = 0.021). Largest changes in ß-diversity of corals occurred within sites (F = 2.764, df1= 35, df2 = 107, p = 0.045) and within localities (F = 4.438, df1= 6, df2 = 29, p = 0.026). Our results suggest that processes operating at spatial scales of hundreds of meters and hundreds of kilometers might both be critical to shape coral assemblage structure in Venezuela, whereas smaller scales (i.e., hundreds of meters) showed to be highly- important for the species turnover component of ß-diversity. This result highlights the importance of creating scale-adapted management actions in Venezuela and likely across the Caribbean region.

4.
PeerJ ; 8: e8429, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351778

RESUMO

The characteristics of coral reef sampling and monitoring are highly variable, with numbers of units and sampling effort varying from one study to another. Numerous works have been carried out to determine an appropriate effect size through statistical power; however, these were always from a univariate perspective. In this work, we used the pseudo multivariate dissimilarity-based standard error (MultSE) approach to assess the precision of sampling scleractinian coral assemblages in reefs of Venezuela between 2017 and 2018 when using different combinations of number of transects, quadrats and points. For this, the MultSE of 36 sites previously sampled was estimated, using four 30m-transects with 15 photo-quadrats each and 25 random points per quadrat. We obtained that the MultSE was highly variable between sites and is not correlated with the univariate standard error nor with the richness of species. Then, a subset of sites was re-annotated using 100 uniformly distributed points, which allowed the simulation of different numbers of transects per site, quadrats per transect and points per quadrat using resampling techniques. The magnitude of the MultSE stabilized by adding more transects, however, adding more quadrats or points does not improve the estimate. For this case study, the error was reduced by half when using 10 transects, 10 quadrats per transect and 25 points per quadrat. We recommend the use of MultSE in reef monitoring programs, in particular when conducting pilot surveys to optimize the estimation of the community structure.

5.
Gac. homeop. Caracas ; 12(1): 25-25, ene.-jun. 2004. ilus
Artigo em Espanhol | LILACS | ID: lil-406139

RESUMO

Se presenta la biografía y trayectoria de un médico humanista reconocido, de gran vocación de servicio, que decide adentrarse de lleno en el campo de la homeopatía para adquirir nuevos enfoques que le ampliaron la posibilidad terapéutica de ayudar a sus pacientes


Assuntos
Biografia , Docentes de Medicina/história , Terapêutica Homeopática , Homeopatia , Venezuela
7.
Asunción; s.n; Nov, 2000. 16 p.
Não convencional em Espanhol | BDNPAR | ID: biblio-1019012
8.
Asunción; sept. 1999. 28 p. ilus.
Monografia em Espanhol, Inglês | LILACS, BDNPAR | ID: lil-270448

RESUMO

Presenta informe parte de una serie de consideraciones relacionadas con la problemática en la gestión delos recursos humanos en salud de Paraguay, resaltando a los personales del Ministerio de Salud Pública yBienestar Social


Assuntos
Mão de Obra em Saúde , Educação Continuada , Paraguai
9.
Asunción; Organización Panamericana de la Salud; set. 1998. 157 p. ilus.
Monografia em Espanhol | PAHO | ID: pah-32709
16.
Brasília; Brasil. Ministério da Saúde; 1983. 31 p. ilus, tab.(Brasil. Ministério da Saúde. Educaçäo e Saúde, Série F, 7).
Monografia em Português | LILACS, BDENF - Enfermagem | ID: biblio-1036193
17.
In. Associaçäo Brasileira de Enfermagem. Anais do XXXIII Congresso Brasileiro de Enfermagem. , Associaçäo Brasileira de Enfermagem;Associaçäo Brasileira de Enfermagem, 2-7 ago. 1981. p.89-96.
Monografia em Português | BDENF - Enfermagem | ID: biblio-1036018
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