838 resultados para spawning grounds


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Nuclear internal transcribed spacer 2 (ITS2) rDNA sequences were used for a molecular phylogenetics analysis of five Onchocerca species. The sister species of the human parasite O. volvulus was found to be the cattle parasite O. ochengi and not O. gibsoni, contrary to chromosomal evidence. The genetic differentiation of two African populations (representing the two African strains) and a Brazilian population of O. volvulus was also studied. Phylogenetic and network reconstruction did not show any clustering of ITS2 alleles on geographic or strain grounds. Furthermore, population genetics tests showed no indication of population differentiation but suggested gene flow among the three populations.

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Supportive breeding is an important tool in conservation management, but its long-term genetic consequences are not well understood. Among the factors that could affect the genetics of the offspring is sperm competition as a consequence of mixed-milt fertilizations - which is still a common practice in many hatcheries. Here, we measured and combined the relevant factors to predict the genetic consequences of various kinds of hatchery-induced sperm competition. We drew a random sample of male Coregonus zugensis (an Alpine whitefish) from a hatchery program and quantified their in vitro sperm potency by integrating sperm velocity during the first minute after activation, and their in vitro milt potency by multiplying sperm potency with milt volume and sperm cell density. We found that not controlling for sperm density and/or milt volume would, at a constant population size, decrease the variance effective number of male breeders N-em by around 40-50%. This loss would decrease with increasing population growth rates. Partial multifactorial breeding and the separate rearing of in total 799 batches of eggs revealed that neither sperm nor milt potency was significantly linked to egg survival. Sperm and milt potency was also not significantly correlated to other potential quality measures such as breeding tubercles or condition factor. However, sperm potency was correlated to male age and milt potency to male growth rate. Our findings suggest that hatchery-induced sperm competition not only increases the loss of genetic variation but may also induce artificial selection, depending on the fertilization protocol. By not equalizing milt volume in multi-male fertilization hatchery managers lose relatively more genetic variation and give fast-growing males a reproductive advantage, while equalizing milt volume reduces the loss of genetic variation and favors younger males who may have fast sperm to compensate for their subdominance at the spawning place. (c) 2007 Elsevier Ltd. All rights reserved.

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The Spanish Society of Nursing Emergency (SEEUE) has several lines documentaries that can be consulted on its web page and that have been spread through various publications: Statutes, scientific recommendations, professional recommendations, statements and allegations, grounds for nursing emergency, guarantees and rules, documents of interest and legislation. Set this that composed the regulatory environment, legal and recommendations which society poses to the collective nurse from the area of the emergency, as well as the rest of actors associated with urgent assistance (institutional and administratively) and through what has been the work of conceptualization and definition in our area the past few years. Part of this documentation offer possibilities for scientific endorsement and professional and invites to continue building knowledge and evidence. It is in this sense in which this work can and should be defined from a literature review approach and under the scheme of "review article". The working Group in Primary Care (PC) of the SEEUE, decided to build a Professional Recommendation (PR) in one of the areas of "uncertainty/variability" in the employment context and historical demand of nurses and other emergency care team on security issues: "The uniform and personal protective equipment for professional teams on prehospital emergency areas”.

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Dengue virus (DENV) and parvovirus B19 (B19V) infections are acute exanthematic febrile illnesses that are not easily differentiated on clinical grounds and affect the paediatric population. Patients with these acute exanthematic diseases were studied. Fever was more frequent in DENV than in B19V-infected patients. Arthritis/arthralgias with DENV infection were shown to be significantly more frequent in adults than in children. The circulating levels of interleukin (IL)-1 receptor antagonist (Ra), CXCL10/inducible protein-10 (IP-10), CCL4/macrophage inflammatory protein-1 beta and CCL2/monocyte chemotactic protein-1 (MCP-1) were determined by multiplex immunoassay in serum samples obtained from B19V (37) and DENV-infected (36) patients and from healthy individuals (7). Forward stepwise logistic regression analysis revealed that circulating CXCL10/IP-10 tends to be associated with DENV infection and that IL-1Ra was significantly associated with DENV infection. Similar analysis showed that circulating CCL2/MCP-1 tends to be associated with B19V infection. In dengue fever, increased circulating IL-1Ra may exert antipyretic actions in an effort to counteract the already increased concentrations of IL-1β, while CXCL10/IP-10 was confirmed as a strong pro-inflammatory marker. Recruitment of monocytes/macrophages and upregulation of the humoral immune response by CCL2/MCP-1 by B19V may be involved in the persistence of the infection. Children with B19V or DENV infections had levels of these cytokines similar to those of adult patients.

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Certifying the absence of Chagas disease transmission by native vectors lacks scientific grounds and weakens long-term control-surveillance systems to the detriment of people living under risk conditions. Instead, a regular "certification of good practice" (including vector control-surveillance, case detection/patient care and blood safety) could help achieve sustained disease control.

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Living-kidney donation offers an option to patients awaiting renal transplantation. Representations about giving-receiving are explored retrospectively in a qualitative study. Questionnaires with open questions were sent to thirty donor-recipient dyads. Interviews were also conducted, during which participants were invited to propose an image representing donation. Thematic analysis was performed on the questionnaires (twenty-nine donors; twenty-five recipients), and on the comments of ten images selected by five donors and five recipients. Percentages are given regarding each part (donors; recipients). In the questionnaires, life (34.5%; 12%), love (27.6%; 40%), quality of life (27.6%; 8%) and generosity (6.9%; 24%) are common grounds regarding giving-a-kidney. Obviousness, hope, personal benefits or duty are expressed by donors. Recipients explain donation through emphatic sentences, qualify it as a gift or refer to the donor's courage or risk-taking. Regarding receiving-a-kidney, life (31%; 60%), gift (10.3%; 28%) and debt (3.4%; 4%) are common grounds. Donors refer to generosity or love. Quality of life, donor's risk-taking or emphatic sentences are characteristic of recipients, who highlight that nobody had to die. Preliminary data on the comments of the images underline that live-donation represents life and love. Mutual help, sharing-act, obviousness and personal benefits are expressed by donors. Recipients use emphatic sentences or refer to quality of life, gift or the difficulty to accept donation. Life and love are common grounds in live-donation. Improvement in quality of life is underlined by recipients, who stress the donor's courage or risk-taking. Donors describe donation as obvious, sometimes accompanied by personal benefits. Feelings of duty (donors) and of debt (recipients) are less discussed. Representations about giving and receiving differ between donors and recipients. These data show the specificity of each perspective. This analysis provides valuable information in order to adapt individual or dyad psychological support in live-donation.

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'Estats fallits' ha arribat a ser un lema popular per als acadèmics i els polítics per igual. En opinió dels governs occidentals i les institucions internacionals, els estats fallits no compleixen amb les condicions necessàries per assolir el desenvolupament econòmic i social i alhora proporcionar un terreny fèrtil per als actors violents conflictes i no estatals que participen en la delinqüència internacional. La Unió Europea té una relació de llarga data amb els països de l'Àfrica subsahariana, molts dels quals es caracteritzen per ser fallat. En aquest treball es pretén analitzar si el compromís retòric de la UE per fer front a la insuficiència de l'Estat es tradueix en un enfocament coherent davant les causes profundes de la fragilitat de l'Estat i pregunta pels factors que expliquen el compromís de la UE amb els problemes que enfronten aquests estats. Mitjançant la comparació de les polítiques europees cap a la República Democràtica del Congo, Sierra Leone i la República Centreafricana, s'argumenta que la resposta de la UE als Estats fallits es desenvolupa d'una manera incoherent esbiaixada cap a les situacions de conflicte en lloc de ser guiat per una preocupació més general per fragilitat . L'anàlisi suggereix que la participació de la UE es deu principalment a interessos coincidents en els Estats membres i de la UE.

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Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare subtype of leukemia/lymphoma, whose diagnosis can be difficult to achieve due to its clinical and biological heterogeneity, as well as its overlapping features with other hematologic malignancies. In this study we investigated whether the association between the maturational stage of tumor cells and the clinico-biological and prognostic features of the disease, based on the analysis of 46 BPDCN cases classified into three maturation-associated subgroups on immunophenotypic grounds. Our results show that blasts from cases with an immature plasmacytoid dendritic cell (pDC) phenotype exhibit an uncommon CD56- phenotype, coexisting with CD34+ non-pDC tumor cells, typically in the absence of extramedullary (e.g. skin) disease at presentation. Conversely, patients with a more mature blast cell phenotype more frequently displayed skin/extramedullary involvement and spread into secondary lymphoid tissues. Despite the dismal outcome, acute lymphoblastic leukemia-type therapy (with central nervous system prophylaxis) and/or allogeneic stem cell transplantation appeared to be the only effective therapies. Overall, our findings indicate that the maturational profile of pDC blasts in BPDCN is highly heterogeneous and translates into a wide clinical spectrum -from acute leukemia to mature lymphoma-like behavior-, which may also lead to variable diagnosis and treatment.

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On Friday May 16, the Ministry of Foreign Affairs of Cuba summoned the newly-appointed charged’affairs of the European Commission in Havana and announced the withdrawal of the application procedure for membership in the Cotonou Agreement of the Africa, Caribbean, and Pacific (ACP) countries, and in fact renouncing to benefit from European development aid.1 In a blistering note published in the Granma official newspaper of the Cuban Communist Party, the government blamed the EU Commission for exerting undue pressure, its alleged alignment with the policies of the United States, and censure for the measures taken by Cuba during the previous weeks.2 In reality, Cuba avoided an embarrasin flat rejection for its application. This was the anti-climatic ending for a long process that can be traced back to the end of the Cold War, in a context where Cuba has been testing alternative grounds to substitute for the overwhelming protection of the Soviet Union

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We analyze the effect of research joint ventures (RJVs) on consumer welfare in an international context when collusion can occur. The main novelty of our analysis is to study the differentiated effect of domestic and international RJVs. The recent literature shows that RJVs with collusion harm consumers. However, our results introduce a qualifi cation to this statement: international RJVs with collusion might be bene ficial for consumers when internationalization costs are high. The EU and US competition policy advises against RJVs that facilitate collusion on the grounds of their expected negative effects. Our results suggest that antitrust authorities should distinguish between domestic and international RJVs and, in certain cases, be more benevolent with international RJVs. Keywords: collusion; domestic research joint venture; international research joint venture JEL Classi fication Numbers: K21, L24, L44, O32

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When one wishes to implement public policies, there is a previous need of comparing different actions and valuating and evaluating them to assess their social attractiveness. Recently the concept of well-being has been proposed as a multidimensional proxy for measuring societal prosperity and progress; a key research topic is then on how we can measure and evaluate this plurality of dimensions for policy decisions. This paper defends the thesis articulated in the following points: 1. Different metrics are linked to different objectives and values. To use only one measurement unit (on the grounds of the so-called commensurability principle) for incorporating a plurality of dimensions, objectives and values, implies reductionism necessarily. 2. Point 1) can be proven as a matter of formal logic by drawing on the work of Geach about moral philosophy. This theoretical demonstration is an original contribution of this article. Here the distinction between predicative and attributive adjectives is formalised and definitions are provided. Predicative adjectives are further distinguished into absolute and relative ones. The new concepts of set commensurability and rod commensurability are introduced too. 3. The existence of a plurality of social actors, with interest in the policy being assessed, causes that social decisions involve multiple types of values, of which economic efficiency is only one. Therefore it is misleading to make social decisions based only on that one value. 4. Weak comparability of values, which is grounded on incommensurability, is proved to be the main methodological foundation of policy evaluation in the framework of well-being economics. Incommensurability does not imply incomparability; on the contrary incommensurability is the only rational way to compare societal options under a plurality of policy objectives. 5. Weak comparability can be implemented by using multi-criteria evaluation, which is a formal framework for applied consequentialism under incommensurability. Social Multi-Criteria Evaluation, in particular, allows considering both technical and social incommensurabilities simultaneously.

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Of all Pacific salmonids, Chinook salmon Oncorhynchus tshawytscha display the greatest variability in return times to freshwater. The molecular mechanisms of these differential return times have not been well described. Current methods, such as long serial analysis of gene expression (LongSAGE) and microarrays, allow gene expression to be analyzed for thousands of genes simultaneously. To investigate whether differential gene expression is observed between fall- and spring-run Chinook salmon from California's Central Valley, LongSAGE libraries were constructed. Three libraries containing between 25,512 and 29,372 sequenced tags (21 base pairs/tag) were generated using messenger RNA from the brains of adult Chinook salmon returning in fall and spring and from one ocean-caught Chinook salmon. Tags were annotated to genes using complementary DNA libraries from Atlantic salmon Salmo salar and rainbow trout O. mykiss. Differentially expressed genes, as estimated by differences in the number of sequence tags, were found in all pairwise comparisons of libraries (freshwater versus saltwater = 40 genes; fall versus spring = 11 genes: and spawning versus nonspawning = 51 genes). The gene for ependymin, an extracellular glycoprotein involved in behavioral plasticity in fish, exhibited the most differential expression among the three groupings. Reverse transcription polymerase chain reaction analysis verified the differential expression of ependymin between the fall- and spring-run samples. These LongSAGE libraries, the first reported for Chinook salmon, provide a window of the transcriptional changes during Chinook salmon return migration to freshwater and spawning and increase the amount of expressed sequence data.

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Contemporary policy makers in most European destination countriesexpress a great concern about reunification of migrants’ families. Newrestrictions multiply in almost all countries, on the grounds thatmigrants would take advantage of a too lax system and that it wouldfoster an influx of non-desirable migrants. So far, quantitative evidenceis scarce on migrants’ practices in matter of family reunification.Taking advantage of a unique longitudinal dataset that includesSenegalese individuals surveyed both at origin (in Senegal) and inEurope (France, Italy and Spain), we perform event-history analyses toshow three things. First, couple separation is very often a long lastingsituation. Second, when separated because of international migration,wives and husbands do not only reunify in Europe but quite commonlyin Senegal. And third, those who reunify in Europe are those who arethe most adapted or adaptable to the European culture and economy.

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Biological reference points are important tools for fisheries management. Reference points are not static, but may change when a population's environment or the population itself changes. Fisheries-induced evolution is one mechanism that can alter population characteristics, leading to "shifting" reference points by modifying the underlying biological processes or by changing the perception of a fishery system. The former causes changes in "true" reference points, whereas the latter is caused by changes in the yardsticks used to quantify a system's status. Unaccounted shifts of either kind imply that reference points gradually lose their intended meaning. This can lead to increased precaution, which is safe, but potentially costly. Shifts can also occur in more perilous directions, such that actual risks are greater than anticipated. Our qualitative analysis suggests that all commonly used reference points are susceptible to shifting through fisheries-induced evolution, including the limit and "precautionary" reference points for spawning-stock biomass, Blim and Bpa, and the target reference point for fishing mortality, F0.1. Our findings call for increased awareness of fisheries-induced changes and highlight the value of always basing reference points on adequately updated information, to capture all changes in the biological processes that drive fish population dynamics.

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When back-calculating fish length from scale measurements, the choice of the body-scale relationship is a fundamental step. Using data from the arctic charrSalvelinus alpinus (L.) of Lake Geneva (Switzerland) we show the need for a curvilinear model, on both statistical and biological grounds. From several 2-parameters models, the log-linear relationship appears to provide the best fit. A 3-parameters, Bertalanffy model did not improve the fit. We show moreover that using the proportional model would lead to important misinterpretations of the data.