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Quantitative information on population size, structure and dynamics are urgently needed for assessing species extinction risk and developing monitoring measures, especially for beetles belonging to the threatened guild of saproxylic organisms. Here freshly cut log piles (FCLP) were tested for the monitoring of the longhorn beetle Morimus asper (Sulzer, 1776) (Coleoptera: Cerambycidae). Novel mathematical models based on presence–absence or count data were compared with the most commonly used capture–recapture methods to investigate if less invasive and easier approaches may be suitable for large-scale monitoring of this species and other large saproxylic beetles. The use of FCLP as bait was reliable to detect the presence and abundance of M. asper, and capture events were not influenced by the phenomena of trap-happiness or trap-shyness. In order to obtain accurate presence–absence estimates of M. asper at a reasonable cost piles of at least 0.25 m3 are suggested. Models which take into account the abundance of the species without marking individuals were the best compromise between costs and accuracy of estimation. Therefore, a reliable assessment of the population size of M. asper, can be based on count data without marking individuals. Because FCLP attract adults of M. asper and other saproxylic beetles, they could act also as potential ecological traps if chipped and/or removed after the sampling season. Therefore, if FCLP are used in monitoring as a part of conservation programmes, the piles should be left until completely decayed.  相似文献   
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Alström Syndrome (ALMS) is a rare genetic disorder (483 living cases), characterized by many clinical manifestations, including blindness, obesity, type 2 diabetes and cardiomyopathy. ALMS is caused by mutations in the ALMS1 gene, encoding for a large protein with implicated roles in ciliary function, cellular quiescence and intracellular transport. Patients with ALMS have extensive fibrosis in nearly all tissues resulting in a progressive organ failure which is often the ultimate cause of death. To focus on the role of ALMS1 mutations in the generation and maintenance of this pathological fibrosis, we performed gene expression analysis, ultrastructural characterization and functional assays in 4 dermal fibroblast cultures from ALMS patients. Using a genome-wide gene expression analysis we found alterations in genes belonging to specific categories (cell cycle, extracellular matrix (ECM) and fibrosis, cellular architecture/motility and apoptosis). ALMS fibroblasts display cytoskeleton abnormalities and migration impairment, up-regulate the expression and production of collagens and despite the increase in the cell cycle length are more resistant to apoptosis. Therefore ALMS1-deficient fibroblasts showed a constitutively activated myofibroblast phenotype even if they do not derive from a fibrotic lesion. Our results support a genetic basis for the fibrosis observed in ALMS and show that both an excessive ECM production and a failure to eliminate myofibroblasts are key mechanisms. Furthermore, our findings suggest new roles for ALMS1 in both intra- and extra-cellular events which are essential not only for the normal cellular function but also for cell-cell and ECM-cell interactions.  相似文献   
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Two-thirds of Earth's surface is covered by oceans, yet the study of this massive integrated living system is still in its infancy. Various environmental variables, such as high salinity, low and changeable nutrient availability and depth-correlated gradients of light, temperature, nutrients and pressure shape the diversity, physiology and ecology of marine species. As oceans present an average depth of 3800 m, deep-sea ecosystems represent the most common marine ecological niche. One of the key environment variables that influences the life and evolution of deep-sea organisms is high pressure. This extreme widespread condition requires specific adaptations, the nature of which remains largely unknown. Recent advances in genomic approaches, such as in sequencing technologies and global expression profiling, are rapidly increasing the data available to understand microbial evolution, biochemistry, physiology and diversity. This review summarises the analysis of the results published so far about microbial high pressure adaptation from a genomic point of view. Understanding high pressure adaptation mechanisms is not just a scientific exercise but has important biotechnological implications. For example, hydrostatic pressure is a reality for food science and technology, both for food preparation and preservation. An understanding of the effects of pressure on biomolecules will expand its use in the medical, industrial and biotechnological fields.  相似文献   
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Saproxylic beetles may act as bio-indicators of high-quality mature woodlands, and their conservation is strongly linked to the quality and quantity of deadwood in a biotope. We tested the effect of deadwood accumulation and habitat variables on saproxylic species richness by investigating six sampling sites under different deadwood management practices that belong to both alluvial and riparian mixed forests of the Po plain, Italy. We sampled 43 obligate saproxylic species. The main factor predicting saproxylic species richness was the amount of deadwood measured by both log diameter and volume. We found a threshold of 0.22 m diameter (confidence interval CI 0.18–0.37 m) and 32.04 m3/ha volume (CI 16.09–64.09 m3/ha) below which saproxylic beetle richness would be significantly reduced and a threshold of 35 m3/ha dead wood volume (CI 33–40 m3/ha) over which species richness increases by <5 %. The other deadwood and environmental components influenced saproxylic beetle richness to a lesser extent; some of them, however, should still be considered for proper management. Forest structure variables describing forest density such as large trees and basal areas have a negative effect on species richness. According to the results of our study, stumps and advanced decaying class are positively correlated, while small logs are negatively correlated to species richness. Thus, in extensively managed forests, the regular cutting of trees should be implemented to create artificial stumps, in order to assure a continuity of deadwood and, in the meantime, increase the number and width of openings in the forest. Moreover, prolonging rotation times can assure the presence of deadwood at intermediate/later stages of decay.  相似文献   
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Helleria brevicornis has a disjunct, peri-Tyrrhenian distribution that mirrors that of several organisms, for which geographic vicariance is invoked, due to the geological events started with the Oligocene split of the Sardo-Corsican microplate from the Pyrenees, and successive separation between Sardinia and Corsica. Molecular phylogenetic analyses demonstrated that such a biogeographic model does not apply to Helleria. The original split of the Sardinian and Corsican lineages originated in the Early Pliocene. Further diversification occurred later. The colonization of the Tuscan archipelago, French, and Italian mainland occurred most recently, but a possible time dependency bias suggests that such colonization was driven by human-transport.  相似文献   
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