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1.
Environ Entomol ; 45(5): 1300-1305, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27566526

RESUMO

A comparison of 95 species of Central European moths, representing 11 families and inhabiting various habitats, was carried out in order to detect the potential impact of biotope on the ultraviolet (UV) light reflectance of their wings. Based on digitized photographs taken under UV light conditions, a phylogeny-controlled redundancy analysis relating UV reflectance to preferred habitat type (xerophilous, mesophilous, and hygrophilous) and habitat openness (open, semiopen, and closed) was carried out. Species preferring hygrophilous habitats displayed significantly higher UV wing reflectance than species inhabiting xerothermic and mesic habitats, and this pattern remained significant even after controlling for phyletic relationships. In contrast, UV wing reflectance displayed no pattern related to habitat openness. Given the higher UV reflectance of water and humid surfaces, we interpret these results, which are based on the first comprehensive sampling of UV reflectance in Central European moths, in terms of predator avoidance under habitat-specific light conditions. We conclude that the moisture content of the environment may markedly contribute to the variation of appearance of moth wings for better imitation habitat characteristics and therefore to increase protection.


Assuntos
Ecossistema , Mariposas/fisiologia , Raios Ultravioleta , Asas de Animais/fisiologia , Animais , Masculino , Pigmentação
2.
ScientificWorldJournal ; 2012: 123760, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22566757

RESUMO

Ambient ozone (O(3)) is an important phytotoxic pollutant, and detailed knowledge of its spatial distribution is becoming increasingly important. The aim of the paper is to compare different spatial interpolation techniques and to recommend the best approach for producing a reliable map for O(3) with respect to its phytotoxic potential. For evaluation we used real-time ambient O(3) concentrations measured by UV absorbance from 24 Czech rural sites in the 2007 and 2008 vegetation seasons. We considered eleven approaches for spatial interpolation used for the development of maps for mean vegetation season O(3) concentrations and the AOT40F exposure index for forests. The uncertainty of maps was assessed by cross-validation analysis. The root mean square error (RMSE) of the map was used as a criterion. Our results indicate that the optimal interpolation approach is linear regression of O(3) data and altitude with subsequent interpolation of its residuals by ordinary kriging. The relative uncertainty of the map of O(3) mean for the vegetation season is less than 10%, using the optimal method as for both explored years, and this is a very acceptable value. In the case of AOT40F, however, the relative uncertainty of the map is notably worse, reaching nearly 20% in both examined years.


Assuntos
Biologia Computacional/métodos , Monitoramento Ambiental/métodos , Ozônio/química , Árvores/química , Poluentes Atmosféricos/química , Altitude , República Tcheca , Sistemas de Informação Geográfica , Modelos Lineares , Estações do Ano , Raios Ultravioleta , Incerteza
3.
ScientificWorldJournal ; 1 Suppl 2: 294-303, 2001 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-12806066

RESUMO

Estimates of dry and wet deposition of nitrogen and sulphur compounds in the Czech Republic for the years 1994 and 1998 are presented. Deposition has been estimated from monitored and modeled concentrations in the atmosphere and in precipitation, where the most important acidifying compounds are sulphur dioxide, nitrogen oxides, ammonia, and their reaction products. Measured atmospheric concentrations of SO2, NOx, NH3, and aerosol particles (SO4(2-), NO3-, and NH4+), along with measured concentrations of SO4(2-), NO3-, and NH4+ in precipitation, weighted by precipitation amounts, were interpolated with Kriging technique on a 10- x 10-km grid covering the whole Czech Republic. Wet deposition was derived from concentration values for SO4(2-), NO3-, and NH4+ in precipitation and from precipitation amounts. Dry deposition was derived from concentrations of gaseous components and aerosol in the air, and from their deposition velocities. A multiple resistance model was used for calculation of SO2, NOx, and NH3 deposition velocities. Deposition velocities of particles were parameterized. It was estimated that the annual average deposition of SOx in the Czech Republic decreased from 1384 to 1027 mol H + ha(-1) a(-1) between 1994 and 1998. The annual average NOy deposition was estimated to be 972 and 919 mol H + ha(-1) a(-1) in 1994 and 1998, respectively. The annual average NHx deposition was estimated to be 887 mol H+ ha(-1) a(-1) and 779 mol H + ha(-1) a(-1) in 1994 and 1998, respectively. It was estimated that the annual average of the total potential acid deposition decreased from 3243 to 2725 mol H + ha(-1) a(-1) between 1994 and 1998. Sulphur compounds (SOx) contributed about 38%, oxidized nitrogen species (NOy) 34%, and reduced nitrogen species (NHx) 28% to the total potential acid deposition in 1998. The wet deposition contributed 42% to the total potential acid deposition in 1998.


Assuntos
Atmosfera/análise , Compostos de Nitrogênio/metabolismo , Compostos de Enxofre/metabolismo , Algoritmos , Amônia/metabolismo , República Tcheca , Ecossistema , Monitoramento Ambiental/métodos , Modelos Teóricos , Óxidos de Nitrogênio/metabolismo , Dióxido de Enxofre/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-10743726

RESUMO

Twelve human embryos and fetuses aged of 7-30 weeks of intrauterinal life were examined to determine the expression of bcl-2 gene in the developing kidney. Tissue samples were routinely processed and three-step indirect immunohistochemical method was used for the detection of Bcl-2 protein. End-point cytophotometry was performed with computer-controlled microscope photometer with a scanning table and the mean relative absorbance of the final product of peroxidase reaction was determined and taken as a measure of Bcl-2 expression. The morphometric evaluation was carried out from the TV display using Weibel s universal hexagonal raster and we determined the relative volume of Bcl-2 positive structures in the various zones of the embryonal kidney. The aim of our research was mapping of the Bcl-2 occurrence in the developing kidney of human embryos and fetuses. The Bcl-2 protein is involved in the regulation of apoptosis and its effect is antiapoptotic. The highest Bcl-2 expression was proved in the cells of metanephrogenic blastema. The lower occurrence of Bcl-2 positive cells was demonstrated in proximal tubules analges+ and it was almost on the borderline of detection in branches of ureteral bud. In the fetal period the marked Bcl-2 expression was maintained in the epithelial cells of proximal tubules analges.


Assuntos
Desenvolvimento Embrionário e Fetal , Regulação da Expressão Gênica no Desenvolvimento , Genes bcl-2 , Rim/embriologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Citofotometria , Embrião de Mamíferos , Feto , Idade Gestacional , Humanos , Rim/citologia , Córtex Renal/embriologia , Medula Renal/embriologia
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