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101.
102.
To test the hypothesis that a switch in diet might cause changes in the abundance and composition of mucous‐dwelling microorganisms, a short‐term experiment was conducted with Atlantic salmon Salmo salar. Fish were fed on three different diets: pelleted S. salar feed, macroinvertebrates or pellets supplemented with an antibiotic. A fourth group of fish was deprived of food throughout the trial. Seven days after manipulating diets, significant differences were found in microbial density and community composition (quantified by different morphologically distinct colonies), particularly between fed and unfed animals. Moreover, food deprivation caused a rapid decrease in the number of epidermal mucous cells of the lateral skin, which may indicate a decrease in mucous secretion and explain differences in the diversity of mucous‐dwelling microbiota observed in the fish. This is the first report of an effect of feeding regime on the abundance of microbial communities associated with cutaneous mucus of fishes.  相似文献   
103.
The world's richest mangrove‐restricted avifauna is in Australia and New Guinea. The history of differentiation of the species involved and their patterns of intraspecific genetic variation remain poorly known. Here, we use sequence data derived from two mitochondrial protein‐coding genes to study the evolutionary history of eight co‐distributed mangrove‐restricted and mangrove‐associated birds from the Australian part of this region. Utilizing a comparative phylogeographical framework, we observed that the study species present concordantly located phylogeographical breaks across their shared geographical distribution, a plausible signature of common mechanisms of vicariance underlying this pattern. Barriers such as the Canning Gap, Bonaparte Gap, and the Carpentarian Gaps all had important but varying degrees of impact on the studied species. The Burdekin Gap along Australia's eastern seaboard probably had only a minor influence as a barrier to gene flow in mangrove birds. Statistical phylogeographical simulations were able to discriminate among alternative scenarios involving six different geographical and temporal population separations. Species exhibiting recent colonizations into mangroves include Rhipidura phasiana, Myiagra ruficollis, and Myzomela erythrocephala. By contrast, Peneoenanthe pulverulenta, Pachycephala melanura, Pachycephala lanioides, Zosterops luteus, and Colluricincla megarhyncha all had deeper histories, reflected as more marked phylogeographical divisions separating populations on the eastern seaboard/Cape York Peninsula from more western regions such as the Arnhem Land, the Pilbara, and the Kimberley. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 574–598.  相似文献   
104.
Rapid and more sensitive methods for the detection and quantification of viable Legionella cells have been developed. In this paper, a comparative analysis of environmental water samples using the ScanVIT-Legionella? method and the traditional “gold standard” method of culturing is realised indicating the usefulness of the ScanVIT method. The ScanVIT-Legionella? method was performed on environmental water samples from different locations of Huesca region (Spain). Legionella micro-colonies should appear green colour and Legionella pneumophila micro-colonies appear red. Twenty-one environmental water samples analysed by standard culture plus five control samples (Two sterile water samples with Legionella as positive controls and three sterile water samples as negative controls). All of them were used to apply ScanVIT-Legionella? method. From of 21 environmental samples eleven were positive, six negative with both methods and four samples were negative for culture method and positive for ScanVIT-Legionella? method. The positive control samples were positive and the negative were negative for both methods. A comparative analysis of the results obtained with two methods showed a strong positive determination coefficient (R2 = 0.99753). The results demonstrate the usefulness of the ScanVIT-Legionella? method as a rapid diagnostic tool in order to provide a diagnosis as quick as possible. ScanVIT-Legionella? method offers a series of advantages such as quickly diagnosis, higher sensitivity and the possibility to identify Legionella spp. and L. pneumophila simultaneously.  相似文献   
105.
The Hazard analysis and critical control points (HACCP) is a preventive system which seeks to ensure food safety and security. It allows product protection and correction of errors, improves the costs derived from quality defects and reduces the final overcontrol. In this paper, the system is applied to the line of cultivation of mushrooms and other edible cultivated fungi. From all stages of the process, only the reception of covering materials (stage 1) and compost (stage 3), the pre-fruiting and induction (step 6) and the harvest (stage 7) have been considered as critical control point (CCP). The main hazards found were the presence of unauthorized phytosanitary products or above the permitted dose (stages 6 and 7), and the presence of pathogenic bacteria (stages 1 and 3) and/or heavy metals (stage 3). The implementation of this knowledge will allow the self-control of their productions based on the system HACCP to any plant dedicated to mushroom or other edible fungi cultivation.  相似文献   
106.
Arnar Árnason  Bob Simpson 《Ethnos》2013,78(4):533-553
This paper explores the processes whereby complex scientific developments are rendered into locally intelligible idioms as part of strategies to incorporate a ‘public’ in decisions which may have profound implications in the longer term. We focus in particular on the recent developments in genetic technologies and take as our example the deCode biogenetic project in Iceland. We trace how the images and metaphors drawn upon by all sides of the debate created powerful resonances with Icelandic history and culture. We analyse these representations and the broader themes of ethnicity and nationalism which they invoke.  相似文献   
107.
The small white‐marmorated longicorn beetle, Monochamus sutor (L.) (Coleoptera: Cerambycidae), is widely distributed throughout Europe and Asia. It is a potential vector of the pine wood nematode, Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle, the causal agent of the devastating pine wilt disease. Volatiles were collected from both male and female beetles after maturation feeding. In analyses of these collections using gas chromatography (GC) coupled to mass spectrometry, a single male‐specific compound was detected and identified as 2‐(undecyloxy)‐ethanol. In analyses by GC coupled to electroantennography the only consistent responses from both female and male antennae were to this compound. Trapping tests were carried out in Spain, Sweden, and China. 2‐(Undecyloxy)‐ethanol was attractive to both male and female M. sutor beetles. A blend of the bark beetle pheromones ipsenol, ipsdienol, and 2‐methyl‐3‐buten‐2‐ol was also attractive to both sexes in Spain and Sweden, and further increased the attractiveness of the 2‐(undecyloxy)‐ethanol. The host plant volatiles α‐pinene, 3‐carene, and ethanol were weakly attractive, if at all, in all three countries and did not significantly increase the attractiveness of the blend of 2‐(undecyloxy)‐ethanol and bark beetle pheromones. 2‐(Undecyloxy)‐ethanol is thus proposed to be the major, if not only, component of the male‐produced aggregation pheromone of M. sutor, and its role is discussed. This compound has been reported as a pheromone of several other Monochamus species and is another example of the parsimony that seems to exist among the pheromones of many of the Cerambycidae. Traps baited with 2‐(undecyloxy)‐ethanol and bark beetle pheromones should be useful for monitoring and control of pine wilt disease, should M. sutor be proven to be a vector of the nematode.  相似文献   
108.
Pollen grains of 30, mainly annual, species from 134 populations of the genus Veronica (Plantaginaceae, formerly Scrophulariaceae) from the Mediterranean Region, have been studied with light and scanning electron microscopy. Three pollen types are defined based on pollen size and exine surface sculpture. In some cases within the study group pollen size can be useful in species determination. Hypothetical relationships of pollen grain size and aperture number with ploidy level, style length and corolla diameter are discussed. The ornamentation of the exine in Veronica, although generally a conservative character within the genus, gives some additional support to the most recent infrageneric classification of Veronica.  相似文献   
109.
The ecology of macroinvertebrate communities in arid regions is still poorly understood. Here we examined how the community structure varied at spatial and temporal scales in streams and tributaries of the Huasco River in semi-arid region of Northern Chile. We expected that macroinvertebrate distribution may be responding to natural processes of mineralization described for Chilean semiarid basins. The relationships among biotic and abiotic variables were assessed through multivariate techniques (principal component analysis, non-metric multidimensional scaling, canonical correspondence analysis), and a two-way analysis of similarity was used to evaluate differences between basins and years (2007, 2008, and 2009). Significant differences in community structure and physical–chemical variables between basins (Del Carmen and Del Tránsito) were found, but not between years. Altitude, Mn, Al, Ca, Na, HCO3, and dissolved oxygen were the variables that best accounted for the communities distribution. In particular, high metals concentration in El Transito basin should determine low density and diversity of macroinvertebrates. Chironomidae, Ephydridae, and Glossiphoniidae were associated to waters with high metals content and acidic pH, whereas Baetidae, Hydroptilidae, and Blephariceridae were associated to sites with more favorable physical–chemical conditions. These results contribute to understand the ecological patterns of macroinvertebrates in arid regions and should lead to conservation and monitoring plans for this remote place.  相似文献   
110.
Methylation of histone arginine residues is an epigenetic mark related to gene expression that is implicated in a variety of biological processes and can be reversed by small-molecule modulators of protein arginine methyltransferases (PRMTs). A series of symmetrical ureas, designed as analogues of the known PRMT1 inhibitor AMI-1 have been synthesized using Pd-catalyzed Ar–N amide bond formation processes or carbonylation reactions as key steps. Their inhibitory profile has been characterized. The enzymatic assays showed a weak effect on PRMT1 and PRMT5 activity for most of the compounds. The acyclic urea that exhibited the strongest effect on the inhibition of the PRMT1 activity also showed the greatest effect on the expression of some androgen receptor target genes (TMPRSS2 and FKBP5), which may be related with its enzymatic activity. Surprisingly, AMI-1 behaved as an activator of PRMT5 activity, a result not reported so far.  相似文献   
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