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191.
192.
Francisco Guil Sandra Agudín Nuria El-Khadir Mariana Fernandez-Olalla Juan Figueredo Francisco G. Domínguez Paloma Garzon Gregorio Gonzalez Jaime Muñoz-Igualada Javier Oria Fernando Silvestre 《European Journal of Wildlife Research》2010,56(4):633-640
Camera trapping is the most used method for surveying medium-sized carnivores in Spain. The main target for these surveys has been the Iberian lynx, the most endangered cat in the world. The Iberian lynx conservation program has received the largest EU LIFE projects grant. So, efficiency is a key goal for managing this grant. During 2003 and 2007, we have applied these funds to the survey of the Iberian lynx in Eastern Sierra Morena (Spain). Using two different techniques, we have studied both to see which is the most efficient. The survey developed in active latrines resulted more efficient than that of scent stations and live prey camera trapping throughout the years, although there has been a variation between years. Otherwise, the live prey method has been the one providing the greatest speed and number of pictures per entrance. We suggest that camera-trapping surveys can be improved in terms of efficiency for a wide range of species, or at least for the Iberian lynx. To improve the results, cameras might be placed in relation to breeding territories. With this determinant, camera-trapping surveys would be shorter than 120 days. Finally, we suggest how those surveys for medium carnivores should be designed. 相似文献
193.
Sébastien Chanfreau Maria Mena Jaime R. Porras-Domínguez Mariana Ramírez-Gilly Miquel Gimeno Pedro Roquero Alberto Tecante Eduardo Bárzana 《Bioprocess and biosystems engineering》2010,33(5):629-638
The syntheses of poly-l-lactide (PLLA) and poly-l-lactide-co-glycolide (PLLGA) is reported in the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate [HMIM][PF6] mediated by the enzyme lipase B from Candida antarctica (Novozyme 435). The highest PLLA yield (63%) was attained at 90 °C with a molecular weight (M
n
) of 37.8 × 103 g/mol determined by size exclusion chromatography. This procedure produced relatively high crystalline polymers (up to 85%
PLLA) as determined by DSC. In experiments at 90 °C product synthesis also occurred without biocatalyst, however, PLLA synthesis
in [HMIM][PF6] at 65 °C followed only the enzymatic mechanism as ring opening was not observed without the enzyme. In addition, the enzymatic
synthesis of PLLGA is first reported here using Novozyme 435 biocatalyst with up to 19% of lactyl units in the resulting copolymer
as determined by NMR. Materials were also characterized by TGA, MALDI-TOF–MS, X-ray diffraction, polarimetry and rheology. 相似文献
194.
Díaz-Lezama N Hernández-Elvira M Sandoval A Monroy A Felix R Monjaraz E 《Biochemical and biophysical research communications》2010,403(1):24-29
Ghrelin is a multifunctional peptide hormone with roles in growth hormone release, food intake and cell proliferation. With ghrelin now recognized as important in neoplastic processes, the aim of this report is to present findings from a series of in vitro studies evaluating the cellular mechanisms involved in ghrelin regulation of proliferation in the PC-3 human prostate carcinoma cells. The results showed that ghrelin significantly decreased proliferation and induced apoptosis. Consistent with a role in apoptosis, an increase in intracellular free Ca(2+) levels was observed in the ghrelin-treated cells, which was accompanied by up-regulated expression of T-type voltage-gated Ca(2+) channels. Interestingly, T-channel antagonists were able to prevent the effects of ghrelin on cell proliferation. These results suggest that ghrelin inhibits proliferation and may promote apoptosis by regulating T-type Ca(2+) channel expression. 相似文献
195.
Raquel Sartor Maria J Mamprim Regina F Takahira Mariana F de Almeida 《Acta veterinaria Scandinavica》2010,52(1):36
Background
Doppler ultrasonography is an important tool for evaluating hepatic portal hemodynamics. However, no study in dogs of different body weights, in the range encountered in routine clinical veterinary practice, has been reported. It can be difficult to obtain an ideal insonation angle when evaluating the main portal vein, so evaluation of the right portal vein branch has been described in humans as an alternative. The aim of this study was to analyze, through Doppler ultrasonography, the hemodynamics in the right portal vein branch in dogs of different body weights. 相似文献196.
Most coevolving relationships between pairs of species are embedded in a broader multispecific interaction network. The mutualistic interaction between Lithophragma parviflorum (Saxifragaceae) and its pollinating floral parasite Greya politella (Lepidoptera, Prodoxidae) occurs in some communities as a pairwise set apart from most other interactions in those communities. In other communities, however, this pair of species occurs with congeners and with other floral visitors to Lithophragma. We analyzed local and geographic differences in the network formed by interactions between Lithophragma plants and Greya moths in communities containing two Lithophragma species, two Greya species, and floral visitors other than Greya that visit Lithophragma flowers. Our goal was to evaluate if non-Greya visitors were common, if visitor assembly differs between Lithophragma species and populations and if these visitors act as effective pollinators. Sympatric populations of L. heterophyllum and L. parviflorum differ in floral traits that may affect assemblies of floral visitors. Visitation rates by non-Greya floral visitors were low, and the asymptotic number of visitor species was less than 20 species in all populations. Lithophragma species shared some of the visitors, with visitor assemblages differing between sites more for L. heterophyllum than for L. parviflorum. Pollination efficacy experiments showed that most visitors were poor pollinators. Single visits to flowers by this assemblage of species resulted in significantly higher seed set in Lithophragma heterophyllum (30.6 ± 3.9 SE) than in L. parviflorum (4.7 ± 3.4 SE). This difference was consistent between sites, suggesting that these visitors provide a better fit to the floral morphology of L. heterophyllum. Overall, none of the non-Greya visitors appears to be either sufficiently common or efficient as a pollinator to impose strong selection on any of these four Lithophragma populations in comparison with Greya, which occurs within almost all populations of these species throughout their geographic ranges. 相似文献
197.
Mariana Royer Gaëtan Herbette Véronique Eparvier Jacques Beauchêne Bernard Thibaut Didier Stien 《Phytochemistry》2010,71(14-15):1708-1713
In order to explain the durability of the Moraceae plant family, phytochemistry of Bagassa guianensis was performed. Ethyl acetate extract was obtained from the heartwood and 18 secondary metabolites were isolated, including 6 moracins [6-O-methyl-moracin M, 6-O-methyl-moracin N and moracin Z; previously identified: moracin M, moracin N and moracin P], 8 stilbenoids [presently identified: (?)-epialboctalol and arachidin 4; previously identified: alboctalol, trans-resveratrol, arachidin 2, trans-oxyresveratrol and artogomezianol], 3 previously identified flavonoids, steppogenin, katuranin and dihydromorin, β-sitosterol and resorcinol. Previous studies suggest that stilbenoids are responsible for the natural durability of wood. Our study has determined that B. guianensis is closely related to Morus sp. in phylogeny and should be included in the Moreae sensu stricto tribe of the Moraceae family. 相似文献
198.
Célia Ferreira Sónia Silva Fábio Faria-Oliveira Eva Pinho Mariana Henriques Cândida Lucas 《BMC microbiology》2010,10(1):238
Background
GUP1 gene was primarily identified in Saccharomyces cerevisiae being connected with glycerol uptake defects in association with osmotic stress response. Soon after, Gup1p was implicated in a complex and extensive series of phenotypes involving major cellular processes. These include membrane and wall maintenance, lipid composition, bud-site selection, cytoskeleton orientation, vacuole morphology, secretory/endocytic pathway, GPI anchors remodelling, and lipid-ordered domains assembly, which is compatible with their inclusion in the Membrane Bound O-acyl transferases (MBOAT) family. In mammals, it has been described as a negative regulator of the Sonic hedgehog pathway involved in morphogenesis, differentiation, proliferation, among other processes. 相似文献199.
Mariana Conte Silvia de Simone Susan J Simmons Carlos L Ballaré Ann E Stapleton 《BMC plant biology》2010,10(1):112
Background
Understanding of the genetic architecture of plant UV-B responses allows extensive targeted testing of candidate genes or regions, along with combinations of those genes, for placement in metabolic or signal transduction pathways. 相似文献200.
Mariana Pehar Kenneth J. O’Riordan Melissa Burns‐Cusato Matthew E. Andrzejewski Carlos Gil Del Alcazar Corinna Burger Heidi Scrable Luigi Puglielli 《Aging cell》2010,9(2):174-190
The longevity‐assurance activity of the tumor suppressor p53 depends on the levels of Δ40p53 (p44), a short and naturally occurring isoform of the p53 gene. As such, increased dosage of p44 in the mouse leads to accelerated aging and short lifespan. Here we show that mice homozygous for a transgene encoding p44 (p44+/+) display cognitive decline and synaptic impairment early in life. The synaptic deficits are attributed to hyperactivation of insulin‐like growth factor 1 receptor (IGF‐1R) signaling and altered metabolism of the microtubule‐binding protein tau. In fact, they were rescued by either Igf1r or Mapt haploinsufficiency. When expressing a human or a ‘humanized’ form of the amyloid precursor protein (APP), p44+/+ animals developed a selective degeneration of memory‐forming and ‐retrieving areas of the brain, and died prematurely. Mechanistically, the neurodegeneration was caused by both paraptosis‐ and autophagy‐like cell deaths. These results indicate that altered longevity‐assurance activity of p53:p44 causes memory loss and neurodegeneration by affecting IGF‐1R signaling. Importantly, Igf1r haploinsufficiency was also able to correct the synaptic deficits of APP695/swe mice, a model of Alzheimer’s disease. 相似文献