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1.
Increased knowledge on the spatial distribution of marine resources is crucial for the implementation of a true ecosystem approach to management and the conservation of marine organisms. For exploited fish species characterized by aggregation behaviour during spawning time, the identification and tracking of spawning areas is essential for a correct assessment of their productivity and population abundance. To elucidate this concept, we reconstructed the spatio‐temporal distribution of adult plaice (Pleuronectes platessa, Pleuronectidae) during spawning time along the 20th century. Historical data reveal that not only the abundance but also the former population richness was much higher than previously estimated and has declined because of protracted over‐exploitation during the last 30 years. We conclude that forecast of stock recovery to former levels of abundance neglecting spatial reorganizations might be over‐optimistic and shaded by a lost memory of the past population richness. These results reinforce the importance of managing exploited marine resources at a greater spatial resolution than has been carried out in the history of fishery management.  相似文献   
2.
Asian bears face major threats due to the impact of human activities as well as a critical lack of knowledge about their status, distribution and needs for survival. Once abundant in northern Pakistan, the Himalayan brown bear (Ursus arctos isabellinus) has been exterminated in most of its former distribution range. It presently occurs sparsely, in small populations, the Deosai National Park supporting the largest isolate. This decline might imply a reduction in genetic diversity, compromising the survival of the population. Using a combination of fecal DNA analysis and field data, our study aimed at assessing the size and genetic status of the Deosai population and give guidelines for its conservation and management. Using fecal genetic analysis, we estimated the population to be 40-50 bears, which compares well with the field census of 38 bears. The northern Pakistani brown bear population may have undergone an approximate 200-300-fold decrease during the last thousand years, probably due to glaciations and the influence of growing human population. However, in spite of the presence of a bottleneck genetic signature, the Deosai population has a moderate level of genetic diversity and is not at immediate risk of inbreeding depression. Gene flow might exist with adjacent populations. We recommend careful monitoring of this population in the future both with field observations and genetic analyses, including sampling of adjacent populations to assess incoming gene flow. The connectivity with adjacent populations in Pakistan and India will be of prime importance for the long-term survival of Deosai bears.  相似文献   
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Axial water flow in the trunks of mature oak trees (Quercus petraea (Matt.) Liebl. and Q. robur L.) was studied by four independent techniques: water absorption from a cut trunk, sap flowmeters, heat pulse velocity (HPV) and thermoimaging. Estimation of the total water flow with sap flowmeters, HPV and water absorption yielded comparable results. We concluded from dye colorations, thermograms and axial profiles of sap flow and heat pulse velocity that, in intact trunks, most of the flow occurred in the current-year ring, where early-wood vessels in the outermost ring were still functional. Nevertheless, there was significant flow in the older rings of the xylem. Total water flow through the trunk was only slightly reduced when air embolisms were artificially induced in early-wood vessels, probably because there was little change in hydraulic conductance in the root-leaf sap pathway. Embolization of the current-year vessels reactivated transport in the older rings.  相似文献   
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Water relations of three Eucalyptus species (E. x trabutii Wilm., E. viminalis Labill., E. dalrympleana Maid.), widely planted in the Mediterranean basin, were analyzed throughout an entire year in relation to natural cold hardening. Osmotic potential, both at saturation and at the turgor loss point, showed a greater reduction during hardening in the more frost-resistant E. viminalis and E. dalrympleana than in the more frost-sensitive E. x trabutii. The hardening capabilities of all species were analyzed in relation to the freezing dehydration index, FDI, a parameter derived from pressure-volume analysis which represents the water lost when cells, initially at the turgor loss point, attain thermodynamic equilibrium with extraplasmatic ice. The FDI at the killing temperature showed little variation either between frost-sensitive and frost-resistant species, or between hardened and non-hardened plants. The index may, therefore, be useful for evaluating a plant's potential for injury by freeze-induced desiccation.  相似文献   
6.
The effects of simulated acid mist treatment on net photosynthesis were determined on Eucalyptus globulus trees. Net assimilation decreased for all the three levels but after 3—4 days recovered only in the pH 3.5 one. Acidity effects are discussed in terms of morphological change to the leaves and as alteration of stomatal and mesophyll resistances. 1 Research work supported by C.N.R., Italy. Special grant I.P.R.A. sub-project 1. paper N. 2014  相似文献   
7.
Mozzarella cheese obtained from buffalo (Bubalus bubalis) milk is a typical Italian product certificated by means of the European Protected Designation of Origin (PDO). Mozzarella cheese can also be obtained from bovine milk or bovine/buffalo milk mixtures, but in this case, it cannot be sold as PDO product, and its label must report the actual ingredients. However, bovine milk in PDO products was frequently detected in the past, suggesting fraudulent addition or accidental contamination. Several methods based on end-point polymerase chain reaction (PCR) have been profitably applied in a large number of tests to detect the presence of undeclared ingredients, also in dairy products. In the present study we report a real-time PCR method able to quantify bovine milk addition to pure buffalo cheese products. We validated a normalized procedure based on two targets: bovine mitochondrial cytochrome b (cyt b) to detect and quantify the bovine DNA and nuclear growth hormone (GH) gene used as a universal reference marker. With the use of this real-time PCR assay, 64 commercial mozzarella di bufala cheese samples purchased at local supermarkets, dairy shops, or directly from cheese manufacturers were analyzed. The results obtained demonstrate that most of the commercial samples were contaminated with bovine milk. Therefore, this assay could be conveniently employed to carry out routine and accurate controls aimed not only to discourage any fraudulent behavior but also to reduce risks for consumer health.  相似文献   
8.
Background: Consuming moderate amounts of lean red meat as part of a balanced diet valuably contributes to intakes of essential nutrients, in this study, we merged phenotypic and genotypic information to characterize the variation in lipid profile and sensory parameters and to represent the diversity among 15 cattle populations. Correlations between fat content, organoleptic characteristics and lipid profiles were also investigated. Methods: A sample of 436 largely unrelated purebred bulls belonging to 15 breeds and reared under comparable management conditions was analyzed. Phenotypic data -including fatness score, fat percentage, individual fatty acids (FA) profiles and sensory panel tests- and genotypic information from 11 polymorphisms was used. Results: The correlation coefficients between muscle total lipid measurements and absolute vs. relative amounts of polyunsaturated FA (PUFA) were in opposite directions. Increasing carcass fat leads to an increasing amount of FAs in triglycerides, but at the same time the relative amount of PUFAs is decreasing, which is in concordance with the negative correlation obtained here between the percentage of PUFA and fat measurements, as well as the weaker correlation between total phospholipids and total lipid muscle content compared with neutral lipids. Concerning organoleptic characteristics, a negative correlation between fiavour scores and the percentage of total PUFA, particularly to n-6 fraction, was found. The correlation between juiciness and texture is higher than with flavour scores. The distribution of SNPs plotted by principal components analysis (PCA) mainly reflects their known trait associations, although influenced by their specific breed allele frequencies. Conclusions: The results presented here help to understand the phenotypic and genotypic background underlying variations in FA composition and sensory parameters between breeds. The wide range of traits and breeds studied, along with the genotypic information on polymorphisms previo  相似文献   
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alpha(1)-Acid glycoprotein modulates apoptosis in bovine monocytes   总被引:1,自引:0,他引:1  
alpha(1)-Acid glycoprotein (AGP, orosomucoid) is a normal constituent of bovine blood. AGP is an immunocalin, a binding protein that can also exert several immunomodulatory functions. In this paper we investigated the effect of bovine alpha(1)-acid glycoprotein (boAGP) on spontaneous and staurosporine-induced apoptosis of blood derived monocytes purified using magnetic cell sorting techniques. Bovine AGP was purified from blood following a chromatographic protocol. The homogeneous protein was used to stimulate the cells as well to raise a polyclonal antibody, that was used throughout all the experiments. When monocytes were incubated with high concentrations of boAGP (0.9 mg/ml), similar to those found in bovine plasma during systemic reaction to inflammation, their spontaneous apoptosis rate was suppressed, as determined by caspase-3/7 enzymatic activity assay. Similar results were obtained when apoptosis was induced by adding staurosporine, a potent protein kinase inhibitor. The apoptosis-modulating activity of boAGP was dependent on its concentration, since physiological concentrations of boAGP (0.3 mg/ml) did not exhibit a statistically significative anti-apoptotic activity. We also investigated whether this apoptosis-modulating activity was dependent on the terminal sialic acid residues exposed on the surface of the protein. Enzymatic treatment with neuraminidase, that cleaves terminal sialic acid residues, completely abolished boAGP's anti-apoptotic activity. These results suggest that the protective effect of AGP is likely mediated by its sialic acid terminal groups.  相似文献   
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