排序方式: 共有64条查询结果,搜索用时 234 毫秒
1.
2.
Fine scale waterbody data improve prediction of waterbird occurrence despite coarse species data 总被引:1,自引:0,他引:1
While modelling habitat suitability and species distribution, ecologists must deal with issues related to the spatial resolution of species occurrence and environmental data. Indeed, given that the spatial resolution of species and environmental datasets range from centimeters to hundreds of kilometers, it underlines the importance of choosing the optimal combination of resolutions to achieve the highest possible modelling prediction accuracy. We evaluated how the spatial resolution of land cover/waterbody datasets (meters to 1 km) affect waterbird habitat suitability models based on atlas data (grid cell of 12 × 11 km). We hypothesized that the area, perimeter and number of waterbodies computed from high resolution datasets would explain distributions of waterbirds better because coarse resolution datasets omit small waterbodies affecting species occurrence. Specifically, we investigated which spatial resolution of waterbodies better explain the distribution of seven waterbirds nesting on ponds/lakes with areas ranging from 0.1 ha to hundreds of hectares. Our results show that the area and perimeter of waterbodies derived from high resolution datasets (raster data with 30 m resolution, vector data corresponding with map scale 1:10 000) explain the distribution of the waterbirds better than those calculated using less accurate datasets despite the coarse grain of the species data. Taking into account the spatial extent (global vs regional) of the datasets, we found the Global Inland Waterbody Dataset to be the most suitable for modelling distribution of waterbirds. In general, we recommend using land cover data of a resolution sufficient to capture the smallest patches of the habitat suitable for a given species’ presence for both fine and coarse grain habitat suitability and distribution modelling. 相似文献
3.
4.
5.
6.
The structure of pyrenetetrasulfonate intercalated with hydrotalcite, having the formula [Zn0.68Al0.32(OH)2][(C16H6O12S4)0.08 · x H2O], was proposed based on molecular simulations combined with experimental data (X-ray powder diffraction, thermogravimetry).
Calculations were done for samples kept at various relative humidities (0%, 84%, 98%). The appropriate models were selected
from comparison of calculated and measured diffraction patterns. Modelling revealed the arrangement of pyrenetetrasulfonate
anions, and the positions and the amount of water molecules in the interlayer space of the host structure. The results confirmed
a large variability in the arrangement of the guest species. In the sample without water molecules (0% RH), pyrenetetrasulfonate
anions formed a layer at the centre of the interlayer distance. For the sample kept at 84% RH, the anions formed two layers
at the thirds of the interlayer. For the sample kept at 98% RH, the anions became tilted with respect to the layered double
hydroxides (LDH) layers and are less organised. Water molecules were arranged in three distinct planes: one in the middle
and two at the quarters of interlayer distance. The number of water molecules obtained by the modelling basically agrees with
the water content as measured by thermogravimetry.
Figure Pyrenetetrasulfonate was intercalated into hydrotalcite and equilibrated at various relative humidities. Structural analysis
was performed using molecular simulations based on X-ray and thermogravimetric data 相似文献
7.
Martin Petrek Cedric Hermans Ví t zslav Kolek Jarmila Fialov Alfred Bernard 《Biomarkers》2002,7(1):58-67
The Clara cell protein (CC16) is a small and readily diffusible protein of 16kDa secreted by bronchiolar Clara cells in the distal airspaces. These epithelial cells are altered in several pulmonary pathological processes induced by various lung toxicants. In the search for a new biomarker of asbestos-induced lung impairment, we used a sensitive immunoassay to determine the levels of CC16 in bronchoalveolar fluid (BALF) and serum of subjects exposed to asbestos compared with a group of healthy controls. In the BALF of asbestos-exposed subjects there was an insignificant trend towards CC16 elevation compared with controls, with a (mean ±SD of 0.81 ±0.65mg l-1 for asbestos-exposed subjects (n = 23) versus 0.39 ±0.19mg l-1 for controls (n = 11) (p = 0.09). In serum, CC16 concentration was significantly increased among asbestos-exposed subjects, with values of 27.2 ±24.0 µg l-1 for asbestos-exposed subjects (n = 34) versus 16.1 ±7.6 µg l-1 for controls (n = 34) (p = 0.01). Regarding the effects of smoking, there were significant differences between generally lower CC16 levels in serum and BALF (p = 0.05 and 0.001, respectively) of smokers compared with the higher levels in non-smokers. Serum CC16 levels positively correlated with those in BALF, which is consistent with a diffusional transfer of CC16 from the bronchoalveolar space into the serum. No association, however, emerged between the levels of CC16 in serum or BALF and either the duration of asbestos exposure or the severity of the lung impairment as assessed by chest X-ray. These findings suggest that exposure to asbestos elicits early changes in the local and, importantly, also the systemic levels of CC16. This pneumoprotein therefore appears as a promising non-invasive biomarker of asbestos-induced lung injury and occupational disease in both smoking and non-smoking exposed subjects. 相似文献
8.
Ales Tichopad Craig Roberts Igor Gembula Petr Hajek Anna Skoczynska Waleria Hryniewicz Karina Jahnz-Rozyk Roman Prymula Ivan Solovi? Vitězslav Kolek 《PloS one》2013,8(8)
We estimate and describe the incidence rates, mortality, and cost of CAP (community-acquired pneumonia), in both inpatient and outpatient settings, in the Czech Republic (CZ), Slovakia (SK), Poland (PL), and Hungary (HU). A retrospective analysis was conducted on administrative data from the health ministry and insurance reimbursement claims with a primary diagnosis of pneumonia in 2009 to determine hospitalization rates, costs, and mortality in adults ≥50 years of age. Patient chart reviews were conducted to estimate the number of outpatient cases. Among all adults ≥50 years, the incidence of hospitalized CAP per 100,000 person years was: 456.6 (CZ), 504.6 (SK), 363.9 (PL), and 845.3 (HU). The average fatality rate for all adults ≥50 is 19.1%, and for each country; 21.7% (CZ), 20.9% (SK), 18.6% (PL), 17.8% (HU). Incidence, fatality, and likelihood of hospitalization increased with advancing age. Total healthcare costs of CAP in EUR was 12,579,543 (CZ); 9,160,774 (SK); 22,409,085 (PL); and 18,298,449 (HU); with hospitalization representing over 90% of the direct costs of treatment. The burden of CAP increases with advancing age in four CEE countries, with hospitalizations driving the costs of CAP upwards in the elderly population. Mortality rates are generally higher than reported in Western EU countries. 相似文献
9.
10.
Petra Patakova Jan Kolek Karel Sedlar Pavlina Koscova Barbora Branska Kristyna Kupkova Leona Paulova Ivo Provaznik 《Biotechnology advances》2018,36(3):721-738
2016, was the 100 years anniversary from launching of the first industrial acetone-butanol-ethanol (ABE) microbial production process. Despite this long period and also revival of scientific interest in this fermentative process over the last 20 years, solventogenic clostridia, mainly Clostridium acetobutylicum, Clostridium beijerinckii, Clostridium saccharoperbutylacetonicum and Clostridium pasteurianum, still have most of their secrets. One such poorly understood mechanism is butanol tolerance, which seems to be one of the most significant bottlenecks obstructing industrial exploitation of the process because the maximum achievable butanol concentration is only about 21 g/L. This review describes all the known cellular responses elicited by butanol, such as modifications of cell membrane and cell wall, formation of stress proteins, extrusion of butanol by efflux pumps, response of regulatory pathways, and also maps both random and targeted mutations resulting in high butanol production phenotypes. As progress in the field is inseparably associated with emerging methods, enabling a deeper understanding of butanol tolerance and production, progress in these methods, including genome mining, RNA sequencing and constructing of genome scale models are also reviewed. In conclusion, a comparative analysis of both phenomena is presented and a theoretical relationship is described between butanol tolerance/high production and common features including efflux pump formation/activity, stress protein production, membrane modifications and biofilm growth. 相似文献