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91.
92.
Ramón Pérez Gil Salcido Inés Arroyo Quiroz Roberto Romero Ramírez 《Biodiversity and Conservation》2009,18(5):1421-1434
Documenting financial resources in biodiversity conservation is a key aspect worldwide in order to set priorities and use
effectively the limited resources available. In Mexico, a megadiverse country, studies on financial resources invested in
biodiversity conservation are scarce and do not address funding for conservation comprehensively. Using recent data from several
sources and applying criteria based on the national priorities for conservation, we compiled, systematized and analyzed data
at a national scale on financing sources, financial resources and conservation organizations and their projects. The information
obtained is presented in various ways and part of it (case study) is already an information system that can be continuously
up-dated. Some of the results show the following: a steady diversification of mechanisms and methods for raising funds for
conservation; an increase in governmental budgets; the acknowledgment by the private sector of the importance of biodiversity
conservation; a greater technical capacity in people and organizations working in conservation; a greater accessibility of
financial resources to support and maintain conservation projects; yet a short term vision in conservation projects; among
other. Although the results obtained through this study are a first approach, they can now be used as a baseline to continue
gathering and analyzing information on conservation financing in Mexico. 相似文献
93.
Silvia Díaz-Fernández Beatriz Arroyo Fabián Casas Monica Martinez-Haro Javier Vi?uela 《PloS one》2013,8(6)
The reduction of game and fish populations has increased investment in management practices. Hunting and fishing managers use several tools to maximize harvest. Managers need to know the impact their management has on wild populations. This issue is especially important to improve management efficacy and biodiversity conservation. We used questionnaires and field bird surveys in 48 hunting estates to assess whether red-legged partridge Alectoris rufa young/adult ratio and summer abundance were related to the intensity of management (provision of supplementary food and water, predator control and releases of farm-bred partridges), harvest intensity or habitat in Central Spain. We hypothesized that partridge abundance would be higher where management practices were applied more intensively. Variation in young/adult ratio among estates was best explained by habitat, year and some management practices. Density of feeders and water points had a positive relationship with this ratio, while the density of partridges released and magpies controlled were negatively related to it. The variables with greatest relative importance were feeders, releases and year. Variations in post-breeding red-legged partridge abundance among estates were best explained by habitat, year, the same management variables that influenced young/adult ratio, and harvest intensity. Harvest intensity was negatively related to partridge abundance. The other management variables had the same type of relationship with abundance as with young/adult ratio, except magpie control. Variables with greatest relative importance were habitat, feeders, water points, releases and harvest intensity. Our study suggests that management had an overall important effect on post-breeding partridge abundance. However, this effect varied among tools, as some had the desired effect (increase in partridge abundance), whereas others did not or even had a negative relationship (such as release of farm-reared birds) and can be thus considered inefficient or even detrimental. We advise reconsidering their use from both ecological and economical points of view. 相似文献
94.
Abstract. We analyse populations of the insectivorous plant Drosophyllum lusitanicum (L.) Link (Droseraceae) and their habitats throughout the species' distribution range (Portugal, Spain and Morocco), and examine their relations. We have surveyed 32 populations and we analyse their demographic structures, accompanying plant communities (by twinspan analyses), and relationships between population features and several edaphic and nonedaphic environmental variables (by multiple regression analyses). Plant communities, their floristic richness and degree of endemism change across the geographical range of Drosophyllum . Populations vary strongly in size, density and age structure. Their recruitment seems largely determined by competition with the surrounding vegetation, while only weak relationships were detected between population performance and other environmental factors. The demographic structure of populations exhibits a marked geographical differentiation, with populations becoming older and sparser towards the north-western part of the range. The largest and presumably most stable populations are mostly found in southern Spanish heathlands, which are nowadays scarcely affected by man. Moroccan populations suffer from browsing by cattle and experience an accelerated generation turnover, while most Portuguese populations occur in afforested areas and experience strongly reduced recruitment. The historical distribution range of Drosophyllum within its peculiar habitat has probably been relatively stable, but recent regional differences in human land use have resulted in present-day differences in population performance, as well as in types and degrees of threat across the three countries involved. Conservation strategies should take into account this range-wide variation and combine approaches on different spatial scales. 相似文献
95.
96.
The genus Triptilion is endemic to central Chile, the Mendoza Province and western Patagonia in Argentina. It is currently composed of seven species: T. achilleae, T. benaventii, T. berteroi, T. capillatum, T. cordifolium, T. gibbosum, and T. spinosum. The main objectives of this paper were to determine the phylogenetic relationships of species of Triptilion. We also traced the evolution of annual and perennial life-forms. Historically a close relationship has been described between genera Triptilion and Nassauvia. Phylogenetic analysis of the genus Triptilion and more closely related genera was undertaken using two nuclear (ITS, ETS) and two chloroplast (trnL-F, rpl32-trnL) markers. The topology of the Bayesian inference tree shows that the genus Triptilion is paraphyletic, because Nassauvia lagascae, the only representative of Nassauvia section Caloptilium grouped with T. achilleae, Clade I. The other species of Triptilion form two clades: Clade II composed of T. cordifolium and T. gibbosum and Clade III that includes T. benaventii, T. berteroi, T. capillatum, and T. spinosum. The genus Triptilion originated and diverged during the Miocene. The results of the life history reconstructions indicate that the common ancestor of Triptilion and Nassauvia was perennial. The annual habit appears to be derived in Triptilion. The life-form of the common ancestor of Triptilion was ambiguous; it may have been annual or perennial. 相似文献
97.
98.
Whether human disturbance can lead to directional selection and phenotypic change in behaviour in species with limited behavioural plasticity is poorly understood in wild animal populations. Using a 19‐year study on Montagu′s harrier, we report a long‐term increase in boldness towards humans during nest visits. The probability of females fleeing or being passive during nest visits decreased, while defence intensity steadily increased over the study period. These behavioural responses towards humans were significantly repeatable. The phenotypic composition of the breeding population changed throughout the study period (4–5 harrier generations), with a gradual disappearance of shy individuals, leading to a greater proportion of bolder ones and a more behaviourally homogeneous population. We further show that nest visit frequency increased nest failure probability and reduced productivity of shy females, but not of bold ones. Long‐term research or conservation programmes needing nest visits can therefore lead to subtle but relevant population compositional changes that require further attention. 相似文献
99.
Olga Zamudio-Prieto Claudia Benítez-Cardoza Rossana Arroyo Jaime Ortega-López 《Biochimica et Biophysica Acta - Proteins and Proteomics》2014,1844(7):1299-1306
EhCP-B9, a cysteine protease (CP) involved in Entamoeba histolytica virulence, is a potential target for disease diagnosis and drug design. After purification from inclusion bodies produced in Escherichia coli, the recombinant EhCP-B9 precursor (ppEhCP-B9) can be refolded using detergents as artificial chaperones. However, the conformational changes that occur during ppEhCP-B9 refolding remain unknown. Here, we comprehensively describe conformational changes of ppEhCP-B9 that are induced by various chemical detergents acting as chaperones, including non-ionic, zwitterionic, cationic and anionic surfactants. We monitored the effect of detergent concentration and incubation time on the secondary and tertiary structures of ppEhCP-B9 using fluorescence and circular dichroism (CD) spectroscopy. In the presence of non-ionic and zwitterionic detergents, ppEhCP-B9 adopted a β-enriched structure (ppEhCP-B9β1) without proteolytic activity at all detergent concentrations and incubation times evaluated. ppEhCP-B9 also exhibits a β-rich structure in low concentrations of ionic detergents, but at concentrations above the critical micelle concentration (CMC), the protein acquires an α + β structure, similar to that of papain but without proteolytic activity (ppEhCP-B9α + β1). Interestingly, only within a narrow range of experimental conditions in which SDS concentrations were below the CMC, ppEhCP-B9 refolded into a β-sheet rich structure (ppEhCP-B9β2) that slowly transforms into a different type of α + β conformation that exhibited proteolytic activity (ppEhCP-B9α + β2) suggesting that enzymatic activity is gained as slow transformation occurs. 相似文献
100.
Lucia Palacios Helena Rosado Vicente Micol Adriana E. Rosato Patricia Bernal Raquel Arroyo Helen Grounds James C. Anderson Richard A. Stabler Peter W. Taylor 《PloS one》2014,9(4)
Galloyl catechins, in particular (-)-epicatechin gallate (ECg), have the capacity to abrogate β-lactam resistance in methicillin-resistant strains of Staphylococcus aureus (MRSA); they also prevent biofilm formation, reduce the secretion of a large proportion of the exoproteome and induce profound changes to cell morphology. Current evidence suggests that these reversible phenotypic traits result from their intercalation into the bacterial cytoplasmic membrane. We have endeavoured to potentiate the capacity of ECg to modify the MRSA phenotype by stepwise removal of hydroxyl groups from the B-ring pharmacophore and the A:C fused ring system of the naturally occurring molecule. ECg binds rapidly to the membrane, inducing up-regulation of genes responsible for protection against cell wall stress and maintenance of membrane integrity and function. Studies with artificial membranes modelled on the lipid composition of the staphylococcal bilayer indicated that ECg adopts a position deep within the lipid palisade, eliciting major alterations in the thermotropic behaviour of the bilayer. The non-galloylated homolog (-)-epicatechin enhanced ECg-mediated effects by facilitating entry of ECg molecules into the membrane. ECg analogs with unnatural B-ring hydroxylation patterns induced higher levels of gene expression and more profound changes to MRSA membrane fluidity than ECg but adopted a more superficial location within the bilayer. ECg possessed a high affinity for the positively charged staphylococcal membrane and induced changes to the biophysical properties of the bilayer that are likely to account for its capacity to disperse the cell wall biosynthetic machinery responsible for β-lactam resistance. The ability to enhance these properties by chemical modification of ECg raises the possibility that more potent analogs could be developed for clinical evaluation. 相似文献