554 research outputs found

    Compromisos del manejo sustentable de los agroecosistemas con los recursos naturales y humanos

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    p.357-364El objetivo de este trabajo es discutir en tomo a la cuestión de la resiliencia y la estabilidad de los sistemas productivos laneros en la región patagónica, la manera en que las decisiones de manejo de la ganadería ovina afectan los recursos naturales y a las personas vinculadas a la explotación ovina. Nuestra tarea nos conduce a transgredir la definición de los términos resiliencia y estabilidad, para aplicarlos a cuestiones del agroecosistema, que incluye al ecosistema y al sistema sociocultural. En la actualidad contamos con marcos teóricos y herramientas de análisis y predicción que nos permitirían prevenir efectos indeseados en las condiciones de producción de alimentos y fibras. Aún así, las soluciones técnicas simplistas parecen inapropiadas en un contexto donde hay múltiples intereses en juego y conflictos potenciales. Considerando que es necesario un acercamiento más cuidadoso en el análisis del uso de los Recursos Naturales, que incluya las motivaciones y respuestas de los distintos actores sociales involucrados (Ludwig, 1993) es preciso para llevar adelante esta empresa desarrollar criterios apropiados. Intentamos develar el lado social de la resiliencia y la estabilidad, ya que en la medida que sea de interés sostener la producción lanera en Patagonia, necesariamente entran en consideración las necesidades de las personas directamente relacionadas con la actividad productiva

    Dominance, Politics, and Physiology: Voters' Testosterone Changes on the Night of the 2008 United States Presidential Election

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    BACKGROUND: Political elections are dominance competitions. When men win a dominance competition, their testosterone levels rise or remain stable to resist a circadian decline; and when they lose, their testosterone levels fall. However, it is unknown whether this pattern of testosterone change extends beyond interpersonal competitions to the vicarious experience of winning or losing in the context of political elections. Women's testosterone responses to dominance competition outcomes are understudied, and to date, a clear pattern of testosterone changes in response to winning and losing dominance competitions has not emerged. METHODOLOGY/PRINCIPAL FINDINGS: The present study investigated voters' testosterone responses to the outcome of the 2008 United States Presidential election. 183 participants provided multiple saliva samples before and after the winner was announced on Election Night. The results show that male Barack Obama voters (winners) had stable post-outcome testosterone levels, whereas testosterone levels dropped in male John McCain and Robert Barr voters (losers). There were no significant effects in female voters. CONCLUSIONS/SIGNIFICANCE: The findings indicate that male voters exhibit biological responses to the realignment of a country's dominance hierarchy as if they participated in an interpersonal dominance contest

    Differential effects of naltrindole on morphine-induced tolerance and physical dependence in rats

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    ABSTRACT This study investigated the effect of delta opioid receptor blockade by naltrindole on the development of physical dependence and tolerance to the antinociceptive and respiratory depressive effects of morphine in rats. Chronic morphine was delivered either by s.c. injection of increasing amounts of morphine over 5 days or by s.c. implantation of morphine pellets. Animals were cotreated with saline or naltrindole. Antinociception and respiratory depression were assessed after administration of a challenge dose of morphine, and withdrawal signs were determined after naloxone challenge. Naltrindole significantly attenuated the development of antinociceptive tolerance after all three chronic treatment regimens. In addition, rats pretreated with naltrindole displayed significantly fewer withdrawal symptoms and less weight loss after a naloxone challenge. In contrast, naltrindole did not prevent the development of tolerance to morphine-induced respiratory depression. These results imply that tolerance to antinociception and physical dependence involves adaptations at interacting mu and delta receptor populations, whereas tolerance to respiratory depression reflects actions of independent mu and delta receptor populations. These findings suggest that delta antagonists may have potential clinical application for decreasing the rapid development of tolerance to opiate-induced analgesia, while allowing for the development of protective tolerance to respiratory depression. There is increasing evidence of interaction between mu and delta opiate receptors (see Traynor and Elliot, 1993 for review). These receptors can coexist on the same neuron, as proposed for receptor populations in the neostriatum Stimulation of delta opiate receptors modulates mu-based antinociception. Two populations of delta receptors (delta 1 and delta 2 ) have been postulated on the basis of pharmacologic evidence There is also evidence that delta receptor activation contributes to the development of morphine-induced tolerance and physical dependence. Coadministration of the delta-2 antagonist 5Ј-NTII with either 100 mg/kg of morphine or morphine pellets over 3 days prevented the normal development of tolerance and dependence in mice, whereas the delta-1-specific antagonist DALCE did not prevent the development of physical dependence in mic

    Blood Pressure Dipping: Ethnicity, Sleep Quality, and Sympathetic Nervous System Activity

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    Blunted blood pressure dipping is an established predictor of adverse cardiovascular outcomes. Although blunted blood pressure dipping is more common in African Americans than whites, the factors contributing to this ethnic difference are not well understood. This study examined the relationships of blood pressure dipping to ethnicity, body mass index, sleep quality, and fall in sympathetic nervous system activity during the sleep-period

    Exclusive Photoproduction of the Cascade (Xi) Hyperons

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    We report on the first measurement of exclusive Xi-(1321) hyperon photoproduction in gamma p --> K+ K+ Xi- for 3.2 < E(gamma) < 3.9 GeV. The final state is identified by the missing mass in p(gamma,K+ K+)X measured with the CLAS detector at Jefferson Laboratory. We have detected a significant number of the ground-state Xi-(1321)1/2+, and have estimated the total cross section for its production. We have also observed the first excited state Xi-(1530)3/2+. Photoproduction provides a copious source of Xi's. We discuss the possibilities of a search for the recently proposed Xi5-- and Xi5+ pentaquarks.Comment: submitted to Phys. Rev.

    Nomenclature- and Database-Compatible Names for the Two Ebola Virus Variants that Emerged in Guinea and the Democratic Republic of the Congo in 2014

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    In 2014, Ebola virus (EBOV) was identified as the etiological agent of a large and still expanding outbreak of Ebola virus disease (EVD) in West Africa and a much more confined EVD outbreak in Middle Africa. Epidemiological and evolutionary analyses confirmed that all cases of both outbreaks are connected to a single introduction each of EBOV into human populations and that both outbreaks are not directly connected. Coding-complete genomic sequence analyses of isolates revealed that the two outbreaks were caused by two novel EBOV variants, and initial clinical observations suggest that neither of them should be considered strains. Here we present consensus decisions on naming for both variants (West Africa: “Makona”, Middle Africa: “Lomela”) and provide database-compatible full, shortened, and abbreviated names that are in line with recently established filovirus sub-species nomenclatures

    A framework for remission in SLE: consensus findings from a large international task force on definitions of remission in SLE (DORIS)

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    Objectives Treat-to-target recommendations have identified 'remission' as a target in systemic lupus erythematosus (SLE), but recognise that there is no universally accepted definition for this. Therefore, we initiated a process to achieve consensus on potential definitions for remission in SLE. Methods An international task force of 60 specialists and patient representatives participated in preparatory exercises, a face-to-face meeting and follow-up electronic voting. The level for agreement was set at 90%. Results The task force agreed on eight key statements regarding remission in SLE and three principles to guide the further development of remission definitions: 1. Definitions of remission will be worded as follows: remission in SLE is a durable state characterised by . (reference to symptoms, signs, routine labs). 2. For defining remission, a validated index must be used, for example, clinical systemic lupus erythematosus disease activity index (SLEDAI)=0, British Isles lupus assessment group (BILAG) 2004 D/E only, clinical European consensus lupus outcome measure (ECLAM)=0; with routine laboratory assessments included, and supplemented with physician's global assessment. 3. Distinction is made between remission off and on therapy: remission off therapy requires the patient to be on no other treatment for SLE than maintenance antimalarials; and remission on therapy allows patients to be on stable maintenance antimalarials, low-dose corticosteroids (prednisone ≤5 mg/day), maintenance immunosuppressives and/or maintenance biologics. The task force also agreed that the most appropriate outcomes (dependent variables) for testing the prognostic value (construct validity) of potential remission definitions are: death, damage, flares and measures of health-related quality of life. Conclusions The work of this international task force provides a framework for testing different definitions of remission against long-term outcomes

    Unions, Dynamism and economic performance

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    This paper explores the relationship between economic performance and US unionism, focusing first on what we do and do not know based on empirical research handicapped by limited data on establishment and firm level collective bargaining coverage. Evidence on the relationship of unions with wages, productivity, profitability, investment, debt, employment growth, and business failures are all relevant in assessing the future of unions and public policy with respect to unions. A reasonably coherent story emerges from the empirical literature, albeit one that rests heavily on evidence that is dated and (arguably) unable to identify truly causal effects. The paper's principal thesis is that union decline has been tied fundamentally to competitive forces and economic dynamism. Implications of these findings for labor law policy and the future of worker voice institutions is discussed briefly in a final section
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