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41.
Aidin Niamir Andrew K. Skidmore Albertus G. Toxopeus Antonio R. Muñoz Raimundo Real 《Diversity & distributions》2011,17(6):1173-1185
Aim The spatial resolution of species atlases and therefore resulting model predictions are often too coarse for local applications. Collecting distribution data at a finer resolution for large numbers of species requires a comprehensive sampling effort, making it impractical and expensive. This study outlines the incorporation of existing knowledge into a conventional approach to predict the distribution of Bonelli’s eagle (Aquila fasciata) at a resolution 100 times finer than available atlas data. Location Malaga province, Andalusia, southern Spain. Methods A Bayesian expert system was proposed to utilize the knowledge from distribution models to yield the probability of a species being recorded at a finer resolution (1 × 1 km) than the original atlas data (10 × 10 km). The recorded probability was then used as a weight vector to generate a sampling scheme from the species atlas to enhance the accuracy of the modelling procedure. The maximum entropy for species distribution modelling (MaxEnt) was used as the species distribution model. A comparison was made between the results of the MaxEnt using the enhanced and, the random sampling scheme, based on four groups of environmental variables: topographic, climatic, biological and anthropogenic. Results The models with the sampling scheme enhanced by an expert system had a higher discriminative capacity than the baseline models. The downscaled (i.e. finer scale) species distribution maps using a hybrid MaxEnt/expert system approach were more specific to the nest locations and were more contrasted than those of the baseline model. Main conclusions The proposed method is a feasible substitute for comprehensive field work. The approach developed in this study is applicable for predicting the distribution of Bonelli’s eagle at a local scale from a national‐level occurrence data set; however, the usefulness of this approach may be limited to well‐known species. 相似文献
42.
Sigrid NW Vorrink Helianthe SM Kort Thierry Troosters Jan-Willem J Lammers 《Respiratory research》2011,12(1):33
Background
Persons with Chronic Obstructive Pulmonary Disease (COPD), performing some level of regular physical activity, have a lower risk of both COPD-related hospital admissions and mortality. COPD patients of all stages seem to benefit from exercise training programs, thereby improving with respect to both exercise tolerance and symptoms of dyspnea and fatigue. Physical inactivity, which becomes more severe with increasing age, is a point of concern in healthy older adults. COPD might worsen this scenario, but it is unclear to what degree. This literature review aims to present the extent of the impact of COPD on objectively-measured daily physical activity (DPA). The focus is on the extent of the impact that COPD has on duration, intensity, and counts of DPA, as well as whether the severity of the disease has an additional influence on DPA.Results
A literature review was performed in the databases PubMed [MEDLINE], Picarta, PEDRO, ISI Web of Knowledge and Google scholar. After screening, 11 studies were identified as being relevant for comparison between COPD patients and healthy controls with respect to duration, intensity, and counts of DPA. Four more studies were found to be relevant to address the subject of the influence the severity of the disease may have on DPA. The average percentage of DPA of COPD patients vs. healthy control subjects for duration was 57%, for intensity 75%, and for activity counts 56%. Correlations of DPA and severity of the disease were low and/or not significant.Conclusions
From the results of this review, it appears that patients with COPD have a significantly reduced duration, intensity, and counts of DPA when compared to healthy control subjects. The intensity of DPA seems to be less affected by COPD than duration and counts. Judging from the results, it seems that severity of COPD is not strongly correlated with level of DPA. Future research should focus in more detail on the relation between COPD and duration, intensity, and counts of DPA, as well as the effect of disease severity on DPA, so that these relations become more understandable. 相似文献43.
Background
Microarray experiments, as well as other genomic analyses, often result in large gene sets containing up to several hundred genes. The biological significance of such sets of genes is, usually, not readily apparent. 相似文献44.
Póvoa MM de Souza RT Lacerda RN Rosa ES Galiza D de Souza JR Wirtz RA Schlichting CD Conn JE 《Memórias do Instituto Oswaldo Cruz》2006,101(2):163-168
In several districts of Boa Vista, state of Roraima, Brazil we found Anopheles (Nyssorhynchus) albitarsis E to be the primary vector of human malaria parasites, and during 2001-2002 it was significantly more abundant than An. darlingi (p < 0.001). Other species sampled were An. (Nys.) braziliensis, An. (Ano.) peryassui, An. (Nys.) nuneztovari, An. (Nys.) oswaldoi s.l., and An. (Nys.) triannulatus. As determined by the ELISA technique An. darlingi had a higher overall infection rate (2.1%) compared with An. albitarsis E (1.2%). However a marginally higher proportion of An. albitarsis E was infected with Plasmodium vivax compared with An. darlingi, and the An. albitarsis E biting index was also much higher These results suggest the importance of An. albitarsis E in malaria transmission in a savannah ecoregion of northern Amazonian Brazil, and reconfirm the importance of An. darlingi even if at lower abundance. 相似文献
45.
Jesús M. Rodilla Maria Teresa Tinoco Julio Cruz Morais Cristina Gimenez Raimundo Cabrera Darío Martín-Benito Lucia Castillo Azucena Gonzalez-Coloma 《Biochemical Systematics and Ecology》2008
We investigated the qualitative and quantitative seasonal variation of the leaf and fruit oils of the Macaronesian endemism Laurus novocanariensis and their plant defensive potential. The monoterpene fraction dominated the leaf (74%) and berry essential oils (73–44%, ripe–unripe). The insect antifeedant effects of these oils were species- and season-dependent against the aphids (Myzus persicae and Rhopalosiphum padi). Overall, the biological effects of these oils correlated with the oxygenated terpene fraction. Among the pure components tested, β-caryophyllene and its oxide were strong antifeedants to Leptinotarsa decemlineata and Spodoptera littoralis. The aphids responded to β-ocimene, β-pinene, 1,8-cineole, linalool (antifeedants) and linalool oxide (attractive to M. persicae). The antifungal effects of the leaf oils on Fusarium spp. were season-dependent. β-Caryophyllene oxide proved to be a strong antifungal. L. novocanariensis oils inhibited Lactuca sativa germination and radicle elongation, the leaves being more effective. Linalool also inhibited seed germination. 相似文献
46.
Prolactin (PRL) promotes maternal behavior (MB), a complex pattern of behavior aimed at maximizing offspring survival. 3α,5α-reduced
neurosteroids may also regulate MB. Indeed, PRL, 3α,5α-reduced neurosteroids, and 5α-reductase (5α-R), the key enzyme in the
biosynthesis of these neuroactive steroids, are all increased in stress situations These facts led us to hypothesize a possible
interrelation between PRL levels and 5α-R. In the present study we quantified mRNA levels of both 5α-R isozymes in prefrontal
cortex of male and female rats after administration of sulpiride, an inductor of PRL secretion. Our results demonstrated that
mRNA levels of both 5α-R isozymes were significantly increased in male and female rats by sulpiride, directly or via sulpiride-induced
hyperprolactinemia. Since 3α,5α-reduced neurosteroids and PRL exert anxiolytic effects in response to stress, these molecules
and 5α-R may possibly participate in a common pathway of significant adaptation to stress situations. 相似文献
47.
José C. Báez Raimundo Real J. Mario Vargas Antonio Flores-Moya 《Phycological Research》2005,53(4):255-265
The aim of the present paper is to identify the possible existence of groups of species in the genera Audouinella (Rhodophyta), Cystoseira (Phaeophyceae) and Cladophora (Chloropyta) with significantly similar distribution patterns (chorotypes), in the western Mediterranean Sea and the Adriatic Sea. Of the 98 species studied, 59 were grouped into 11 chorotypes, whereas 39 species remained ungrouped. Thirty‐eight species were included in a generalist chorotype, whereas 6 chorotypes were monospecific. The relationships with the environmental factors that could explain the chorotypes are discussed. 相似文献
48.
Dependence of broad-scale geographical variation in fleshy-fruited plant species richness on disperser bird species richness 总被引:1,自引:0,他引:1
Aim We analysed the interdependence of avian frugivore‐ and fruited plant‐species richness at the scale of major river basins across Europe, taking into account several environmental factors along different spatial gradients. Location Continental Europe and the British Isles. Methods We focused on wintering birds and autumn/winter fruiting plants, and used major river basins as geographical units and Structural Equation Modelling as the principal analytical tool. Results The statistical influence of disperser species richness on fleshy‐fruited plant species richness is roughly double that of the reverse. Broad‐scale variation in frugivore richness is more dependent on environmental factors than on fruited plant richness. However, the influence of disperser richness on plant richness is four times higher than the influence of environmental factors. Environmental influences on both birds and plants are greater than purely spatial influences. Main conclusions Our results are interpreted as indicating that biotic dispersal of fruits strongly affects broad‐scale geographical trends of fleshy‐fruited plant species richness, whereas richness of fruited plants moderately affects frugivore richness. 相似文献
49.
Farfán Miguel A. Vargas Juan M. Real Raimundo Palomo Luis J. Duarte Jesús 《Acta theriologica》2004,49(3):319-335
To analyse the population structure and reproductive biology of the Iberian hareLepus granatensis Rosenhauer, 1856, 498 hares (264 males and 234 females) were collected in monthly samples from October 1998 to September
1999. Females reached larger sizes than males, with approximately 400 g difference in body mass on reaching sexual maturity.
The total sex ratio was 1∶1, with a bias in favour of males in winter. Sexually active males and females appeared in every
month but August, when no sexually active female was found. Births occurred in every month and were more frequent between
March and July. Seasonal variation in kidney fat index (KFI) followed a similar pattern in males and females, with an increase
in mid-autumn and a decline at the end of winter. Reproductive activity appeared in every month, with a maximum from February
to June. Reproductively hyperactive females (simultaneously pregnant and nursing) appeared in every month except in January,
with a first peak in March and a second lower peak in May–June. Litter size fluctuated between 1 and 7 leverets. The most
frequent gestations involved 1 or 2 foetuses. The mean annual litter size was 2.08 and the average number of litters per productive
female per year was estimated to be 3.48. The maximum productivity was recorded between March and May. The total annual production
of young per adult female was estimated to be 7.21. The minimum annual survival rate of young was 27.91%. On the basis of
these results we propose to maintain the limit of the hunting period between October and December. We discuss the relationship
between the low young/adult ratio obtained and the hunting method used. 相似文献
50.