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21.
This paper describes a study of the possibility of obtaining regression models by means of partial least squares (PLS) and multiple linear regression (MLR) that would enable us to correlate a series of parameters, such as the concentration of short-chain organic acids, higher alcohols, and phenolic compounds with the age of vintage Sherry wines or "anadas". The aim of this study is to characterize how these parameters evolve with aging. If this could be done, it would then be possible to guarantee the age of such wines using objective variables. A PLS regression model was established that allows the age to be predicted with a mean deviation of 1.6 years with respect to the age of the wines. In the case of the MLR, a model with 6 variables was obtained that gives a mean deviation of 3.3 years in the predictions.  相似文献   
22.
For decades, research and development efforts have focused on fish cultivation in floating cages. Despite this focus, and the considerable private and public sector resources invested in these systems, there is a scarcity of economic data derived from the great number of variables present in these systems. A reliable way of generating economic studies is through systems modeling that relates biological, environmental, technical, and economic variables. This study presents results from a computer simulation of seabream production in floating cages under two scenarios: one representing conditions in the Mediterranean Sea, and the other in the Atlantic Ocean. A company operating in the Atlantic (Canary Islands, Spain) provided the majority of data, though some of them were provided by the University of Las Palmas, also in the Canary Islands. Given the assumptions in the simulation case study, the production cost for 1 kg of seabream in floating cages in the described systems is US$2.64 in the Mediterranean and US$2.90 in the Atlantic, and the internal rates of return were 27% and 59%, respectively. The results of model sensitivity analysis for both scenarios show that this cultivation system is more sensitive in the Mediterranean than in the Atlantic. This means that changes in system variables convey lower effects on the production and economic results in the Atlantic scenario than in the Mediterranean. In both scenarios, the feed ration size was one of the variables that improved feed conversion rates. It also improved costs and profitability in greater proportions than the other variables. The reduction of the feed ration below the levels recommended in feed tables lowered the feed conversion rate but increased the number of days in the seabream cultivation cycle, leading to higher production costs and lower internal rates of return. The analysis also showed that greater benefits and profitability could be obtained by raising production capacity through increases in the final stocking density of the system.  相似文献   
23.
Practical "top-down" approaches appear to be the most suitable for the evaluation of measurement uncertainty in pesticide residue testing laboratories, where analytical procedures are routinely applied to a large number of pesticide/food combinations. The opposite approach, "bottom-up" evaluation of measurement uncertainty, leads to great difficulties in evaluating all of the pesticides in a consistent way. Among the top-down approaches, there are two main ways in which measurement uncertainty can be estimated: One is based on default values, which are based on previous extensive interlaboratory experience and the proven accuracy of the laboratory; these include the Horwitz equation or the fit-for-purpose relative standard deviation (FFP-RSD). The other is based on experimental data from the quality control work of the laboratory: within-laboratory reproducibility, interlaboratory validation, or a combination of results obtained in proficiency tests. The principal existing guidelines from various bodies (Eurachem, Nordtest, and Eurolab) all propose different approaches for calculating measurement uncertainty. In this paper, the main top-down approaches are evaluated and compared using the data from the European Proficiency Test Database for Fruits and Vegetables and the Multiresidue Method validation databases obtained from the National Reference and Official Laboratories in Europe. The main conclusion of the comparative study is that a default expanded measurement uncertainty value of 50% could satisfy all of the requirements for facilitating and harmonizing, worldwide, the intercomparability of the pesticide residue confidence results between laboratories.  相似文献   
24.
The genomic regions encoding the putative movement protein (MP), coat protein (CP) and intergenic region (IGR) of seven Spanish isolates of the Parietaria mottle virus which infects tomato plants (PMoV-T) were sequenced. Values for the genetic diversity of the PMoV-T isolates were 0.056, 0.047 and 0.013 for the CP, MP genes and IGR, respectively. Nucleotide and amino acid sequence comparison of the seven PMoV-T isolates with those of PMoV revealed significant differences. All of them had a cytosine deletion at position 1366, also confirmed in an Italian tomato isolate, which involves a start codon for the CP gene different from that for the PMoV sequence, resulting in a CP 16 amino acids shorter than the PMoV CP. The certainty of a cytosine deletion only associated to the tomato isolates or the possibility of a mistake in the PMoV published sequence are the two hypotheses that could explain this difference. Structural motifs highly conserved in Ilarviruses were identified in PMoV-T MP and CP. A stable hairpin structure is proposed for IGR, by the initiation site for subgenomic RNA 4 synthesis. Phylogenetic analysis of CP and MP amino acid sequences showed that Spanish PMoV-T isolates form a separate group from PMoV and other members of the Ilarvirus genus. Comparative analysis with different PMoV isolates including tomato isolates from other regions and isolates from different hosts are necessary to confirm this differentiation.  相似文献   
25.
During a survey carried out in August 2013 along all coastal areas of north-eastern Tunisia (governorships of Bizerte, Ariana, Tunis, Ben Arous, Nabeul, Sousse), eucalyptus trees were found to be highly infested by the invasive pest Glycaspis brimblecombei Moore, 1964, also known as red gum lerp psyllid. This insect, native to the Australian region and secondarily dispersed also in the Americas, Mauritius, Madagascar and South Africa, very recently started to invade the Mediterranean region and in almost 5 years has spread to the Iberian Peninsula, Italy, Greece and Morocco. Its presence in Tunisia (which is recorded here for the first time) most probably dates back to summer 2012, since typical necrotic spots caused by the lerp of the psyllid had already been noted on leaves during spring 2013. No presence of its main parasitoid – Psyllaephagus bliteus Riek – nor of any other natural enemy, was noted up to now during our survey in Tunisia.  相似文献   
26.
Fagonia cretica L. is an important component of Mediterranean dry grasslands and a rare and isolated species of Italian flora. In this study, an assessment is presented on the distribution, habitat, and conservation status of F. cretica in Italy. The results of field investigation and herbarium analysis show that this species grows in a small area within the southern Calabria region characterized by a warmest and driest Mediterranean climate on the Italian peninsula. F. cretica is a semi-desert plant species growing in Italy in only one peripheral and isolated population at the northern limit of its distribution. Plant community analysis, using the phytosociological method, shows that F. cretica grows in wintergreen perennial dry grasslands dominated by Lygeum spartum and Hyparrhenia hirta. F. cretica plant communities are located in thermo-xeric habits such as south-, southeast-and east-facing slopes on clays and sandy clays in southern Calabria. The population of F. cretica is fragmented in six neighbouring localities, with two of which belonging to a Site of Community Importance(SCI). The conservation status of F. cretica population is not very good, and is defined as "Critically Endangered" in accordance with IUCN criteria. There are many threats affecting the F. cretica population in Italy, primarily the changes in land uses due to urban expansion and reforestation with exotic plants. The southern end of the Italian peninsula hosts other plants from thermo-xeric habits that do not adapt to the current local climate. This territory can be considered as a microrefugia for plants currently distributed in the arid territory of the southern Mediterranean. These results contribute to the discussion of some conservation measures, and the possibility of establishing a micro-reserve. For all these reasons, we propose to include F. cretica in the lists of protected plant species at regional(Calabria) and country(Italy) scales in Italy.  相似文献   
27.
Continued contact between humans and animals, in combination with the ever-increasing movement of human and animal populations that is one effect of globalization, contributes to the spread of diseases, often with detrimental effects on public health. This has led professionals involved in both animal health and public health to recognize veterinary public health (VPH) as a key area for their activities to address the human-animal interface. Veterinarians, a profession with major involvement in this field, are in need of specific knowledge and skills to prevent and control public-health problems. As a result, VPH must be directly integrated into veterinary educational programs. At present, only few veterinary schools have specific VPH programs; in most institutions, VPH does not feature as a specific subject in either undergraduate or post-graduate curricula. SAPUVET and SAPUVETNET II are network projects supported by the ALFA program of the European Union (EU). Their main objectives are to reach a common understanding between European and Latin American universities in the definition of the areas in which VPH is important in their respective countries, and to design a harmonized training program for veterinarians in VPH, by making use of new technological applications and innovative teaching methodologies. The elaboration of educational material in combination with case studies presenting real-life problems provides a basis to apply the knowledge acquired on VPH. It is envisaged that the material and modules developed during the two projects will be integrated into the veterinary curricula of the participating universities, as well as in other partner organizations.  相似文献   
28.
Testicular leiomyomas and gonadal dysfunctions are not commonly reported in teleost and particularly in broodstock fish. In the present work, a testicular leiomyoma related to an unusual case of spermatogenic failure syndrome, in a broodstock seabass coming from an Italian aquaculture farm, is reported. At gross pathology, the circumscribed neoplasia showed several white nodular masses, originating from the gonad, deforming the anatomo-physiological shape. From light microscopy, the presence of neoplastic tissue islands with spindle cells with a whirling pattern and the low presence of connective tissue were evident and originated from smooth muscle cells. Seminiferous tubules showed severe azoospermia with the absence of sperm cells even closer to the neoplastic area. Immunohistochemical analysis was positive for alpha-SMA, desmin and vimentin but negative for S-100, confirming a diagnosis of leiomyoma. This is the first report of spermatogenic failure syndrome associated with a testicular leiomyoma in fish from broodstock. More efforts should be made in studying broodstock fish pathologies related to fish maintenance and hormonal treatments that could economically affect aquaculture production.  相似文献   
29.
Several experiments of maceration of a sherry wine vinegar with different fruits (orange, lemon, strawberry, grapefruit, and lime) have been carried out. After optimization (only peel, no heating and seven days as maximum time of maceration), parameters such as polyphenolic content, superoxide anion scavenging ability (related to antioxidant activity) and ascorbic acid content were determined in sherry wine vinegars macerated with two amounts of peel and for two maceration times (3 and 7 days). The analysis of variance pointed to a clear relationship (p<0.01) between type of fruit and amount of peel and polyphenolic content. The factor "time" was practically not significant for any polyphenol. Sherry wine vinegars macerated with different fruits exhibited higher superoxide anion scavenger ability, with the maximum values found for the vinegar macerated with lemon peel. The correlation analysis showed that the superoxide anion scavenger ability of the vinegars macerated, and thus their antioxidant activity, was highly correlated (p<0.01) with several polyphenols, especially with naringin, hesperidin, neohesperidin and gentisic acid and not with the ascorbic acid content.  相似文献   
30.
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