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161.
The financial cost of biodiversity conservation varies widely around the world and such costs should be considered when identifying countries to best focus conservation investments. Previous global prioritizations have been based on global models for protected area management costs, but this metric may be related to other factors that negatively influence the effectiveness and social impacts of conservation. Here we investigate such relationships and first show that countries with low predicted costs are less politically stable. Local support and capacity can mitigate the impacts of such instability, but we also found that these countries have less civil society involvement in conservation. Therefore, externally funded projects in these countries must rely on government agencies for implementation. This can be problematic, as our analyses show that governments in countries with low predicted costs score poorly on indices of corruption, bureaucratic quality and human rights. Taken together, our results demonstrate that using national-level estimates for protected area management costs to set global conservation priorities is simplistic, as projects in apparently low-cost countries are less likely to succeed and more likely to have negative impacts on people. We identify the need for an improved approach to develop global conservation cost metrics that better capture the true costs of avoiding or overcoming such problems. Critically, conservation scientists must engage with practitioners to better understand and implement context-specific solutions. This approach assumes that measures of conservation costs, like measures of conservation value, are organization specific, and would bring a much-needed focus on reducing the negative impacts of conservation to develop projects that benefit people and biodiversity. 相似文献
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163.
Paula Arribas Josefa Velasco Pedro Abellán David Sánchez‐Fernández Carmelo Andújar Piero Calosi Andrés Millán Ignacio Ribera David T. Bilton 《Journal of Biogeography》2012,39(5):984-994
Aim In aquatic ecosystems, standing (lentic) and running (lotic) waters differ fundamentally in their stability and persistence, shaping the comparative population genetic structure, geographical range size and speciation rates of lentic versus lotic lineages. While the drivers of this pattern remain incompletely understood, the suite of traits making up the ability of a species to establish new populations is instrumental in determining such differences. Here we explore the degree to which the association between habitat type and geographical range size results from differences in dispersal ability or fundamental niche breadth in the members of the Enochrus bicolor complex, an aquatic beetle clade with species across the lentic–lotic divide. Location Western Mediterranean, with a special focus on North Africa, the Iberian Peninsula and Sicily. Methods DNA sequences for four loci were obtained from species of the E. bicolor complex and analysed using phylogenetic inference. Dispersal and establishment abilities were assessed in lentic–lotic species pairs of the complex, using flight wing morphometrics and thermal tolerance ranges as surrogates, respectively. Results There were clear differences in range size between the lotic and lentic taxa of the complex, which appears to have had a lotic origin with two transitions to standing waters. Only small differences were observed in temperature tolerance and acclimation ability between the two lotic–lentic sister species studied. By contrast, wing morphometrics revealed clear, consistent differences between lotic and lentic Enochrus species pairs, the latter having a higher dispersal capacity. Main conclusions We hypothesize that there have been two habitat shifts from lotic to lentic waters, which have allowed marked expansions in geographical range size in western Mediterranean species of the E. bicolor complex. Differences in dispersal rather than in establishment ability appear to underlie differences in geographical range extent, as transitions to lentic waters were associated with changes in wing morphology, but not in thermal tolerance range. In this lineage of water beetles, selection for dispersal in geologically short‐lived lentic systems has driven the evolution of larger range sizes in lentic taxa compared with those of their lotic relatives. 相似文献
164.
As rates of global warming increase rapidly, identifying species at risk of decline due to climate impacts and the factors affecting this risk have become key challenges in ecology and conservation biology. Here, we present a framework for assessing three components of climate‐related risk for species: vulnerability, exposure and hazard. We used the relationship between the observed response of species to climate change and a set of intrinsic traits (e.g. weaning age) and extrinsic factors (e.g. precipitation seasonality within a species geographic range) to predict, respectively, the vulnerability and exposure of all data‐sufficient terrestrial non‐volant mammals (3,953 species). Combining this information with hazard (the magnitude of projected climate change within a species geographic range), we identified global hotspots of species at risk from climate change that includes the western Amazon basin, south‐western Kenya, north‐eastern Tanzania, north‐eastern South Africa, Yunnan province in China, and mountain chains in Papua‐New Guinea. Our framework identifies priority areas for monitoring climate change effects on species and directing climate mitigation actions for biodiversity. 相似文献
165.
A novel double nucleotide substitution in the HMG box of the SRY gene associated with Swyer syndrome 总被引:2,自引:0,他引:2
E. Battiloro Barbara Angeletti Maria Cristina Tozzi Lida Bruni Sergio Tondini Piero Vignetti Roberto Verna E. D’Ambrosio 《Human genetics》1997,100(5-6):585-587
We describe a novel double nucleotide substitution in the SRY gene of a 46,XY female with gonadal dysgenesis or Swyer syndrome.
The SRY sequence was analysed by both the single-strand conformational polymorphism assay and direct DNA sequencing of products
from the polymerase chain reaction. A double nucleotide substitution was identified at codon 18 of the conserved HMG box motif,
causing an arginine to asparagine amino-acid substitution. The altered residue is situated in the high mobility group (HMG)-related
box of the SRY protein, a potential DNA-binding domain. Since the mutation abolishes one HhaI recognition site, the results were confirmed by HhaI restriction mapping. No other mutations were found in the remaining regions of the gene. The corresponding DNA region from
the patient’s brother was analysed and found to be normal. We conclude that the SRY mutation in the reported XY female occurred
de novo and is associated with sex reversal.
Received: 16 December 1996 / Accepted: 5 May 1997 相似文献
166.
Renzo Cini Piero Zanello Arnaldo Cinquantini Arturo Colligiani Calogero Pinzino Giorgio Valentini 《Inorganica chimica acta》1984,88(1):105-113
The electrochemical behaviour in aprotic solvent of the complexes {M[bis-(2-hydroxy-l-naphthylideneimine-3-propyl)amine]}, where M = Mn(II), Co(II), Fe(II), Ni(II) and Cu(II) is reported. The complexes were prepared and characterized by elemental analysis, infrared and visible spectroscopy and magnetic susceptibility measurements. In addition the reactivity towards dioxygen of the Mn(II), Fe(II) and Co(II) derivatives was investigated, mainly by cyclic voltammetry and gas-volumetric uptake measurements. The results indicate that the Co(II) complexes are able to add dioxygen reversibly, while Mn(II) and Fe(II) compounds undergo an irreversible oxygenation process. The pathway of the dioxygenation processes is tentatively interpreted on the basis of the electrochemical responses. The results confirm that the location of the oxidation potential allows one to predict whether a compound is able to react with dioxygen, but it is not sufficient to predict whether the dioxygenation reaction proceeds reversibly. 相似文献
167.
168.
The conventionally protected oligopeptides of the two homologous series Boc-(L -Ile)n-OMe and Boc-(D -aIle)n-OMe (n = 2–6) were synthesized in a standard stepwise fashion and their uv and CD spectra in 2,2,2-trifluoroethanol, and solid-state ir spectra were investigated. In addition, two oligomeric products derived from the NCAs of L -isoleucine and of D -allo-isoleucine and having a DP of 20 and 12, respectively, were studied in the solid state by x-ray and ir. No substantial differences between the properties of the diastereomeric oligomers in the solid state were noticed, a β-structure being very likely at least for the Boc-protected hexapeptides and the higher oligomers. In contrast, differences were observed between the spectroscopic properties of the diastereomeric oligopeptides, and especially of the hexapeptides, in trifluoroethanol solution. The different properties of the hexapeptides in solution were related to the existence, in the case of Boc-(L -Ile)6-OMe, of soluble molecular aggregates in which the peptide chains assume the β-conformation. These results provide an additional example of the influence of the configuration of asymmetric carbon atoms of the side chains on the conformational properties of peptide molecules in solution. 相似文献
169.
Mechanism of Oncogenic Transformation by Rous Sarcoma Virus: I. Intracellular Inactivation of Cell-Transforming Ability of Rous Sarcoma Virus by 5-Bromodeoxyuridine and Light 总被引:7,自引:7,他引:0
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Chick embryo fibroblasts brought into stationary phase of growth by maintenance in serum-free Eagle's MEM medium were infected with the Bryan strain of Rous sarcoma virus (B-RSV) and incubated for 18 hr in the presence of 5-bromo-deoxyuridine (BUdR). The cells were then allowed to resume growth and deoxyribonucleic acid (DNA) synthesis by addition of an enriched F12 medium containing serum and RSV antibody to prevent spread of viral infection. After 48 hr, the cultures were exposed for various periods to visible light, overlaid with solid culture medium, and observed for the appearance of foci of transformed cells. In cultures treated with BUdR at the time of infection, exposure to light resulted in a suppression of focus formation of from 50 to 90% in various experiments. Treatment with BUdR for 18 hr before infection or on the day after infection, followed by exposure to light, had no effect on focus formation. In cultures in which almost all cells were infected, treatment with BUdR followed by exposure to light did not result in cell death. This suggests that suppression of transformation is not due to selective killing of infected cells by this treatment but rather to the intracellular inactivation of the transforming ability of Rous sarcoma proviral DNA. 相似文献
170.