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1.
Sci Total Environ ; 658: 1293-1305, 2019 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-30677991

RESUMEN

Marine harbours are the focus of a diverse range of activities and subject to multiple anthropogenically induced pressures. Support for environmental management options aimed at improving degraded harbours depends on understanding the factors which influence people's perceptions of harbour environments. We used an online survey, across 12 harbours, to assess sources of variation people's perceptions of harbour health and ecological engineering. We tested the hypotheses: 1) people living near impacted harbours would consider their environment to be more unhealthy and degraded, be more concerned about the environment and supportive of and willing to pay for ecological engineering relative to those living by less impacted harbours, and 2) people with greater connectedness to the harbour would be more concerned about and have greater perceived knowledge of the environment, and be more supportive of, knowledgeable about and willing to pay for ecological engineering, than those with less connectedness. Across twelve locations, the levels of degradation and modification by artificial structures were lower and the concern and knowledge about the environment and ecological engineering were greater in the six Australasian and American than the six European and Asian harbours surveyed. We found that people's perception of harbours as healthy or degraded, but not their concern for the environment, reflected the degree to which harbours were impacted. There was a positive relationship between the percentage of shoreline modified and the extent of support for and people's willingness to pay indirect costs for ecological engineering. At the individual level, measures of connectedness to the harbour environment were good predictors of concern for and perceived knowledge about the environment but not support for and perceived knowledge about ecological engineering. To make informed decisions, it is important that people are empowered with sufficient knowledge of the environmental issues facing their harbour and ecological engineering options.

2.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 2282-4, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-25471442

RESUMEN

This is the first study to identify and determine the phylogenetics of neritids found in Malaysia. In total, twelve species from the family Neritidae were recorded. Ten species were from the genus Nerita and two species were from the genus Neritina. DNA barcodes were successfully assigned to each species. Although some of these species were previously reported in the region, three are only presently reported in this study. The dendrogram showed Nerita and Neritina strongly supported in their respective monophyletic clades. Phylogenetic positions of some species appeared unstable in the trees. This could be due to the differences in a small number of nucleotides, thus minimizing genetic variation between each specimen and species.


Asunto(s)
Código de Barras del ADN Taxonómico , Variación Genética , Genoma Mitocondrial , Moluscos/genética , Animales , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Malasia , Moluscos/clasificación , Filogenia
3.
Genet Mol Res ; 14(2): 5677-84, 2015 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-26125766

RESUMEN

The mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) gene has been universally and successfully utilized as a barcoding gene, mainly because it can be amplified easily, applied across a wide range of taxa, and results can be obtained cheaply and quickly. However, in rare cases, the gene can fail to distinguish between species, particularly when exposed to highly sensitive methods of data analysis, such as the Bayesian method, or when taxa have undergone introgressive hybridization, over-splitting, or incomplete lineage sorting. Such cases require the use of alternative markers, and nuclear DNA markers are commonly used. In this study, a dendrogram produced by Bayesian analysis of an mtDNA COI dataset was compared with that of a nuclear DNA ATPS-α dataset, in order to evaluate the efficiency of COI in barcoding Malaysian nerites (Neritidae). In the COI dendrogram, most of the species were in individual clusters, except for two species: Nerita chamaeleon and N. histrio. These two species were placed in the same subcluster, whereas in the ATPS-α dendrogram they were in their own subclusters. Analysis of the ATPS-α gene also placed the two genera of nerites (Nerita and Neritina) in separate clusters, whereas COI gene analysis placed both genera in the same cluster. Therefore, in the case of the Neritidae, the ATPS-α gene is a better barcoding gene than the COI gene.


Asunto(s)
Código de Barras del ADN Taxonómico , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Gastrópodos/genética , Animales , Teorema de Bayes , Gastrópodos/clasificación , Filogenia
4.
Genet Mol Res ; 10(2): 1237-44, 2011 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-21732288

RESUMEN

Blood cockles are among the most economically important brackish water invertebrates found in Malaysia. However, our knowledge of blood cockle phylogeny and systematics is rudimentary, especially for the species Tegillarca granosa. It is unclear, for instance, whether the cockles occurring on the west coast of peninsular Malaysia constitute a single species, or multiple, phylogenetically distinct species. We performed the first DNA molecular phylogenetic analysis of T. granosa to distinguish it from other related species found in other parts of the world and to create a DNA database for the species. An approximately 585-nucleotide fragment of the mitochondrial DNA (cytochrome oxidase I, COI) was sequenced for 150 individual cockles, representing 10 populations: three from the north, four from the central part and three from the southern part of peninsular Malaysia. Phylogenetic analyses of the resulting dataset yielded tree topologies that not only showed the relationship between T. granosa and its closest relatives but its position in the evolutionary tree. Three mitochondrial clades were evident, each containing an individual genus. Using the mutation rate of the COI gene, the divergence time between T. granosa and its closest related species was estimated to be 460 thousand years ago. This study provides a phylogenetic framework for this ecologically prominent and commercially important cockle species.


Asunto(s)
Cardiidae/genética , Filogenia , Animales , Cardiidae/clasificación , ADN/genética , Humanos , Malasia
5.
Genet Mol Res ; 10(2): 1245-61, 2011 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-21732289

RESUMEN

We examined genetic variation in blood cockles in an effort to obtain information useful for the sustainability, management, and the stability of this species as a major commodity in the fisheries sector. Ten populations of cockles were sampled from the north to the south of the west coast of peninsular Malaysia. The cockles were collected in collaboration with the Fisheries Research Institute, Penang. The population genetic analysis of the cockles were studied via RAPD-PCR and mtDNA sequencing. Three hundred individuals were analyzed with RAPD-PCR experiments. High gene diversity over all loci was observed (Shannon index = 0.549 ± 0.056 and Nei's gene diversity = 0.4852 ± 0.0430 among 35 loci). The second method, mtDNA sequencing, was employed to complement the information obtained from RAPD-PCR. The gene selected for mtDNA sequencing was cytochrome c oxidase I (COI). One hundred and fifty individuals were sequenced, yielding a partial gene of 585 bp. Statistical analysis showed homogeneity in general but did reveal some degree of variability between the populations in Johor and the rest of the populations. The Mantel test showed a positive but nonsignificant correlation between geographic and genetic distances (r = 0.2710, P = 0.622), as in the RAPD analysis. We propose that the homogeneity between distant populations is caused by two factors: 1) the translocation of the spats; 2) larvae are carried by current movement from the north of the peninsula to the south. The different genetic composition found in Johor could be due to pollution, mutagenic substances or physical factors such as the depth of the water column. This population genetic study is the first for this species in peninsular Malaysia. The data from this study have important implications for fishery management, conservation of blood cockles and translocation policies for aquaculture and stock enhancement programs.


Asunto(s)
Cardiidae/genética , Conservación de los Recursos Naturales , Marcadores Genéticos , Animales , Secuencia de Bases , Cartilla de ADN , ADN Mitocondrial/genética , Reacción en Cadena de la Polimerasa , Técnica del ADN Polimorfo Amplificado Aleatorio
6.
Clin Ter ; 162(3): 209-15, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21717044

RESUMEN

OBJECTIVE: There is paucity of literature on the measurement of the quality of life in post stroke patients in the developing countries. The main objective of this study was to determine the quality of life (QOL) of post stroke patients. MATERIALS AND METHODS: A cross-sectional study was conducted on 107 post stroke patients in two centers. The data was obtained during the period of January 2009 till May 2009 using purposive sampling method. A total of 68 males and 39 females participated in this study. Stroke Specific Quality Of Life (SS-QOL) version 2.0 was used. Cronbach's alpha values for SS-QOL ranged between 0.73 and 0.89. RESULTS: The mean ± SD of the QOL score was 141.79 ± 40.32. The mean ± SD of the age was 65.47 ± 11.79 years. Result showed significant negative association between age and QOL of post stroke patients (r = - 0.199, p= 0.040). Domains mostly affected by stroke compared to pre-stroke were mobility (69%) and energy (64%). There were two domains in SS-QOL significantly predicted the QOL of post stroke patients. These domains were work and productivity (ß= 2.277, t= 2.145, p= 0.035) and thinking (ß= 1.927, t= 2.567, p= 0.012). CONCLUSION: Few items from this measurement tool may not be appropriate in a developing country because of the different cultural background. There is a need to develop appropriate post stroke patient measurement tool based on local practice.


Asunto(s)
Calidad de Vida , Accidente Cerebrovascular , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Salud Urbana
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