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61.
The chemical signals of solitary and territorial felid species are essential for their intraspecific communication. We studied the selection of plant substrates during the fecal marking behavior of the European wildcat Felis silvestris from September 2008 to June 2009 in a protected area in Northwest Spain. The aim of the study was to examine the selection of plants as signal posts with respect to their physical characteristics. We hypothesized that wildcats deposit their fecal marks on plants with physical characteristics (e.g., size, species, and visual conspicuousness) that enhance the olfactory and visual effectiveness of the signal. Our results indicate that diameter, plant group, visual conspicuousness, and interaction between the diameter and plant group influence the decision of wildcats to deposit their fecal marks on plants. The wildcats chose plants with greater diameters and greater visual conspicuousness as scent-marking posts. Moreover, the wildcats chose woody and herbaceous plants, and certain plant species were marked more frequently than expected at random. Indeed, our results indicate that the fecal marks were not randomly distributed on the plants: the wildcats chose to place their marks on plants with certain physical characteristics that maximized the detectability of the signal by intruders and potential mates, thus facilitating the spatial distribution of the species. 相似文献
62.
Potentiometric mass titration (PMT) technique has been adapted to determine the pH
pzc of four vegetable wastes: grape stalks, cork, yohimbe bark and olive stones wastes used for Cu(II) removal. The pH at the
point zero charge (pH
pzc), determined by PMT, are compared with that obtained by two classical techniques: mass titration (MT) and immersion technique
(IT). PMT has been found to be an easy and appropriate technique to determine pH
pzc of the studied materials. From the results, the knowledge of sorbents pH
pzc provides information about the possible attraction and repulsion between sorbent and sorbate but in any case enables to ensure
that electrostatic force is one of the mechanisms that takes place in metal sorption. 相似文献
63.
64.
Nelzair A. Vianna Daniel Gonçalves Flavia Brandão Roberta P. de Barros Gilberto M. Amado Filho Rodrigo O. Meire João Paulo M. Torres Olaf Malm Argemiro D’Oliveira Júnior Leonardo R. Andrade 《Environmental science and pollution research international》2011,18(3):416-427
Purpose
The aims of this paper were to quantify the heavy metals (HM) in the air of different sites in Rio de Janeiro (RJ) and Salvador (SA) using Tillandsia usneoides (Bromeliaceae) as a biomonitor, and to study the morphology and elemental composition of the air particulate matter (PM) retained on the Tillandsia surface. 相似文献65.
O. E. Diekmann L. Gouveia J. A. Perez C. Gil-Rodriguez E. A. Serrão 《Marine Biology》2010,157(9):2109-2115
Seagrasses and their habitat are declining worldwide. Zostera noltii in the Canary Islands has been drastically reduced, mainly by anthropogenic disturbance, to three small surviving patches
in a single harbor in Lanzarote. A previous genetic study, using neutral microsatellite markers, revealed that these patches
consist of a single clonal individual. Here, an assignment test, using microsatellite data, was used to locate the most likely
population of origin from a set of possible donor populations. Our results show that the Moulay Bousselham population in northern
Morocco is assigned as the most likely population of origin (88%), although the probability of being at one generation time
distance is low (2.7%). This result, however, allows locating the most closely related stands that may be the most successful
donor populations for future restoration based on shoot or seed transplantation. 相似文献
66.
Valme Jurado Angel Fernandez-Cortes Soledad Cuezva Leonila Laiz Juan Carlos Cañaveras Sergio Sanchez-Moral Cesareo Saiz-Jimenez 《Die Naturwissenschaften》2009,96(9):1027-1034
The conservation of rock-art paintings in European caves is a matter of increasing interest. This derives from the bacterial
colonisation of Altamira Cave, Spain and the recent fungal outbreak of Lascaux Cave, France—both included in the UNESCO World
Heritage List. Here, we show direct evidence of a fungal colonisation of rock tablets in a testing system exposed in Altamira
Cave. After 2 months, the tablets, previously sterilised, were heavily colonised by fungi and bacteria. Most fungi isolated
were labelled as entomopathogens, while the bacteria were those regularly identified in the cave. Rock colonisation was probably
promoted by the dissolved organic carbon supplied with the dripping and condensation waters and favoured by the displacement
of aerosols towards the interior of the cave, which contributed to the dissemination of microorganisms. The role of arthropods
in the dispersal of spores may also help in understanding fungal colonisation. This study evidences the fragility of rock-art
caves and demonstrates that microorganisms can easily colonise bare rocks and materials introduced into the cavity. 相似文献
67.
68.
69.
MarÍA JOSÉ Ruiz‐López Natalia Gañan José Antonio Godoy Ana Del Olmo Julian Garde Gerardo Espeso Astrid Vargas Fernando Martinez Eduardo R. S. Roldán Montserrat Gomendio 《Conservation biology》2012,26(6):1121-1129
The relation among inbreeding, heterozygosity, and fitness has been studied primarily among outbred populations, and little is known about these phenomena in endangered populations. Most researchers conclude that the relation between coefficient of inbreeding estimated from pedigrees and fitness traits (inbreeding‐fitness correlations) better reflects inbreeding depression than the relation between marker heterozygosity and fitness traits (heterozygosity‐fitness correlations). However, it has been suggested recently that heterozygosity‐fitness correlations should only be expected when inbreeding generates extensive identity disequilibrium (correlations in heterozygosity and homozygosity across loci throughout the genome). We tested this hypothesis in Mohor gazelle (Gazella dama mhorr) and Iberian lynx (Lynx pardinus). For Mohor gazelle, we calculated the inbreeding coefficient and measured heterozygosity at 17 microsatellite loci. For Iberian lynx, we measured heterozygosity at 36 microsatellite loci. In both species we estimated semen quality, a phenotypic trait directly related to fitness that is controlled by many loci and is affected by inbreeding depression. Both species showed evidence of extensive identity disequilibrium, and in both species heterozygosity was associated with semen quality. In the Iberian lynx the low proportion of normal sperm associated with low levels of heterozygosity was so extreme that it is likely to limit the fertility of males. In Mohor gazelle, although heterozygosity was associated with semen quality, inbreeding coefficient was not. This result suggests that when coefficient of inbreeding is calculated on the basis of a genealogy that begins after a long history of inbreeding, the coefficient of inbreeding fails to capture previous demographic information because it is a poor estimator of accumulated individual inbreeding. We conclude that among highly endangered species with extensive identity disequilibrium, examination of heterozygosity‐fitness correlations may be an effective way to detect inbreeding depression, whereas inbreeding‐fitness correlations may be poor indicators of inbreeding depression if the pedigree does not accurately reflect the history of inbreeding. Correlaciones Heterocigosidad‐ Adaptabilidad y Depresión Endogámica en Dos Especies de Mamíferos Críticamente en Peligro 相似文献
70.
Brooke E. Willborg Eniola R. Ibirogba Ayssa Teles Abrao Trad Lourenço Sbragia Dean Potter Rodrigo Ruano 《黑龙江环境通报》2021,41(1):159-176
We conducted a comprehensive evidence-based review on the epidemiology and current standard of care of gastroschisis management as well as the pathophysiology, rationale and feasibility of fetal therapy as a viable alternative. Gastroschisis is a periumbilical abdominal wall defect characterized by abdominal viscera herniation in utero. It affects 4 in 10 000 live births, but the prevalence has steadily increased in recent years. Gastroschisis is typically diagnosed on routine second-trimester ultrasound. The overall prognosis is favorable, but complex gastroschisis, which accounts for about 10% to 15% of cases, is associated with a higher mortality, significant disease burden and higher healthcare costs due to long- and short-term complications. The current standard of care has yet to be established but generally involves continued fetal surveillance and multidisciplinary perinatal care. Postnatal surgical repair is achieved with primary closure, staged silo closure or sutureless repair. Experimental animal studies have demonstrated the feasibility of in utero closure, antiinflammatory therapy and prenatal regenerative therapy. However, reports of early preterm delivery and amnioinfusion trials have failed to show any benefit in humans. Further experimental studies and human trials are necessary to demonstrate the potential benefit of fetal therapy in gastroschisis. 相似文献