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1.
Braz. j. biol ; 78(2): 318-327, May-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888865

RESUMO

Abstract This is the first report on analysis of habitat complexity and heterogeneity of the Pantanal wetland. The Pantanal encompasses a peculiar mosaic of environments, being important to evaluate and monitor this area concerning conservation of biodiversity. Our objective was to indirectly measure the habitat complexity and heterogeneity of the mosaic forming the sub-regions of the Pantanal, by means of remote sensing. We obtained free images of Normalized Difference Vegetation Index (NDVI) from the sensor MODIS and calculated the mean value (complexity) and standard deviation (heterogeneity) for each sub-region in the years 2000, 2008 and 2015. The sub-regions of Poconé, Canoeira, Paraguai and Aquidauana presented the highest values of complexity (mean NDVI), between 0.69 and 0.64 in the evaluated years. The highest horizontal heterogeneity (NDVI standard deviation) was observed in the sub-region of Tuiuiú, with values of 0.19 in the years 2000 and 2015, and 0.21 in the year 2008. We concluded that the use of NDVI to estimate landscape parameters is an efficient tool for assessment and monitoring of the complexity and heterogeneity of the Pantanal habitats, applicable in other regions.


Resumo Este é o primeiro trabalho sobre análise da complexidade e heterogeneidade de habitats do Pantanal. O Pantanal é constituído por um mosaico de ambientes com características peculiares, sendo importante a avaliação e o monitoramento dessa área voltado para a conservação da biodiversidade. O objetivo do estudo é mensurar de forma indireta a complexidade e a heterogeneidade do mosaico de habitats os quais formam as sub-regiões do Pantanal, por meio do sensoriamento remoto. Foram obtidas, gratuitamente, imagens de índice de vegetação por diferença normalizada (NDVI) do sensor MODIS e calculado o valor de média (complexidade) e desvio padrão (heterogeneidade) para cada sub-região do Pantanal, para os anos de 2000, 2008 e 2015. Os pantanais de Poconé, Canoeira, Paraguai e Aquidauana são as regiões que apresentaram os maiores valores de complexidade (NDVI médio), variando entre 0.69 a 0.64 para os anos avaliados. Maior heterogeneidade (NDVI desvio padrão) foi observada na sub-região pantaneira do Tuiuiú, sendo o valor para os anos de 2000 e 2015 igual a 0.19 e para o ano de 2008 o valor de 0.21, o que implica que a região tem a maior heterogeneidade horizontal quando comparada com as demais sub-regiões. Constata-se que o uso de NDVI na estimativa de parâmetros da paisagem é uma ferramenta eficiente para o reconhecimento e monitoramento da complexidade e heterogeneidade de habitats do Pantanal, replicável em outras regiões.


Assuntos
Monitoramento Ambiental/métodos , Ecossistema , Biodiversidade , Áreas Alagadas , Tecnologia de Sensoriamento Remoto , Brasil
2.
Braz J Biol ; 78(2): 318-327, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28832837

RESUMO

This is the first report on analysis of habitat complexity and heterogeneity of the Pantanal wetland. The Pantanal encompasses a peculiar mosaic of environments, being important to evaluate and monitor this area concerning conservation of biodiversity. Our objective was to indirectly measure the habitat complexity and heterogeneity of the mosaic forming the sub-regions of the Pantanal, by means of remote sensing. We obtained free images of Normalized Difference Vegetation Index (NDVI) from the sensor MODIS and calculated the mean value (complexity) and standard deviation (heterogeneity) for each sub-region in the years 2000, 2008 and 2015. The sub-regions of Poconé, Canoeira, Paraguai and Aquidauana presented the highest values of complexity (mean NDVI), between 0.69 and 0.64 in the evaluated years. The highest horizontal heterogeneity (NDVI standard deviation) was observed in the sub-region of Tuiuiú, with values of 0.19 in the years 2000 and 2015, and 0.21 in the year 2008. We concluded that the use of NDVI to estimate landscape parameters is an efficient tool for assessment and monitoring of the complexity and heterogeneity of the Pantanal habitats, applicable in other regions.


Assuntos
Biodiversidade , Ecossistema , Monitoramento Ambiental/métodos , Áreas Alagadas , Brasil , Tecnologia de Sensoriamento Remoto
3.
Am J Hum Genet ; 66(6): 1821-32, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10777718

RESUMO

Type 1 Gaucher disease (GD), a non-neuronopathic lysosomal storage disorder, results from the deficient activity of acid beta-glucosidase (GBA). Type 1 disease is panethnic but is more prevalent in individuals of Ashkenazi Jewish (AJ) descent. Of the causative GBA mutations, N370S is particularly frequent in the AJ population, (q approximately .03), whereas the 84GG insertion (q approximately .003) occurs exclusively in the Ashkenazim. To investigate the genetic history of these mutations in the AJ population, short tandem repeat (STR) markers were used to map a 9.3-cM region containing the GBA locus and to genotype 261 AJ N370S chromosomes, 60 European non-Jewish N370S chromosomes, and 62 AJ 84GG chromosomes. A highly conserved haplotype at four markers flanking GBA (PKLR, D1S1595, D1S2721, and D1S2777) was observed on both the AJ chromosomes and the non-Jewish N370S chromosomes, suggesting the occurrence of a founder common to both populations. Of note, the presence of different divergent haplotypes suggested the occurrence of de novo, recurrent N370S mutations. In contrast, a different conserved haplotype at these markers was identified on the 84GG chromosomes, which was unique to the AJ population. On the basis of the linkage disequilibrium (LD) delta values, the non-Jewish European N370S chromosomes had greater haplotype diversity and less LD at the markers flanking the conserved haplotype than did the AJ N370S chromosomes. This finding is consistent with the presence of the N370S mutation in the non-Jewish European population prior to the founding of the AJ population. Coalescence analyses for the N370S and 84GG mutations estimated similar coalescence times, of 48 and 55.5 generations ago, respectively. The results of these studies are consistent with a significant bottleneck occurring in the AJ population during the first millennium, when the population became established in Europe.


Assuntos
Efeito Fundador , Doença de Gaucher/genética , Glucosilceramidase/genética , Judeus/genética , Mutação de Sentido Incorreto/genética , Algoritmos , Substituição de Aminoácidos/genética , Mapeamento Cromossômico , Sequência Conservada/genética , Europa (Continente) , Doença de Gaucher/enzimologia , Frequência do Gene/genética , Marcadores Genéticos/genética , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Sequências de Repetição em Tandem/genética , Fatores de Tempo
4.
J Clin Invest ; 103(5): 731-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10074491

RESUMO

Cathepsin K, a lysosomal cysteine protease critical for bone remodeling by osteoclasts, was recently identified as the deficient enzyme causing pycnodysostosis, an autosomal recessive osteosclerotic skeletal dysplasia. To investigate the nature of molecular lesions causing this disease, mutations in the cathepsin K gene from eight families were determined, identifying seven novel mutations (K52X, G79E, Q190X, Y212C, A277E, A277V, and R312G). Expression of the first pro region missense mutation in a cysteine protease, G79E, in Pichia pastoris resulted in an unstable precursor protein, consistent with misfolding of the proenzyme. Expression of five mature region missense defects revealed that G146R, A277E, A277V, and R312G precursors were unstable, and no mature proteins or protease activity were detected. The Y212C precursor was activated to its mature form in a manner similar to that of the wild-type cathepsin K. The mature Y212C enzyme retained its dipeptide substrate specificity and gelatinolytic activity, but it had markedly decreased activity toward type I collagen and a cathepsin K-specific tripeptide substrate, indicating that it was unable to bind collagen triple helix. These studies demonstrated the molecular heterogeneity of mutations causing pycnodysostosis, indicated that pro region conformation directs proper folding of the proenzyme, and suggested that the cathepsin K active site contains a critical collagen-binding domain.


Assuntos
Catepsinas/genética , Disostoses/genética , Mutação , Catepsina K , Catepsinas/química , Feminino , Humanos , Masculino , Conformação Proteica
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