2,323 research outputs found

    Change in the North Atlantic circulation associated with the mid-Pleistocene transition

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    The southwestern Iberian margin is highly sensitive to changes in the distribution of North Atlantic currents and to the position of oceanic fronts. In this work, the evolution of oceanographic parameters from 812 to 530 ka (MIS20-MIS14) is studied based on the analysis of planktonic foraminifer assemblages from site IODP-U1385 (37 degrees 34.285' N, 10 degrees 7.562' W; 2585m b.s.l.). By comparing the obtained results with published records from other North Atlantic sites between 41 and 55 degrees N, basin-wide paleoceano-graphic conditions are reconstructed. Variations of assemblages dwelling in different water masses indicate a major change in the general North Atlantic circulation during MIS16, coinciding with the definite establishment of the 100 ky cyclicity associated with the mid-Pleistocene transition. At the surface, this change consisted in the redistribution of water masses, with the subsequent thermal variation, and occurred linked to the northwestward migration of the Arctic Front (AF), and the increase in the North Atlantic Deep Water (NADW) formation with respect to previous glacials. During glacials prior to MIS16, the NADW formation was very weak, which drastically slowed down the surface circulation; the AF was at a southerly position and the North Atlantic Current (NAC) diverted southeastwards, developing steep south-north, and east-west, thermal gradients and blocking the arrival of warm water, with associated moisture, to high latitudes. During MIS16, the increase in the meridional overturning circulation, in combination with the northwestward AF shift, allowed the arrival of the NAC to subpolar latitudes, multiplying the moisture availability for ice-sheet growth, which could have worked as a positive feedback to prolong the glacials towards 100 ky cycles.info:eu-repo/semantics/publishedVersio

    Consensus must be found on intravenous fluid therapy management in trauma patients

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    Introduction: Trauma is an important cause of death among young people and 30-40% of this mortality rate is due to hypovolemic shock, intensified by trauma's lethal triad: Hypothermia, Acidosis, and Coagulopathy. Nurses are responsible for managing fluid therapy administration in trauma victims. The purpose of this study is to analyse the reasons why intravenous fluid therapy is recommended for trauma patients' hemodynamic stabilization. Methods: This narrative literature review included published and unpublished studies in English, Spanish or Portuguese between 1994 and January 2019. The search results were analyzed by two independent reviewers. Inclusion criteria encompasses quantitative studies involving trauma victims aged over 18 who underwent fluid therapy in a prehospital assessment context. Results&Discussion: 11 quantitative studies were included. 9 involved the use of fluid therapy for hypotension treatment and 2 of the studies analyzed involved the use of warmed fluid therapy for hypothermia treatment. The analysis performed reveals that the administration of aggressive fluid therapy seems to be responsible for the worsening of the lethal triad. In the presence of traumatic brain injury, permissive hypotension is not allowed due to the negative impact on cerebral perfusion pressure. Used as warming measure, warmed fluid therapy does not seem to have a significant impact on body temperature. Conclusions: There is no consensus regarding the administration of fluid therapy to trauma patients. This conclusion clearly supports the need to develop more randomized controlled trials in order to understand the effectiveness of such measure when it comes to control hypovolemia and hypothermia.info:eu-repo/semantics/publishedVersio

    Projeto colaborativo de formação de professores para o ensino de ciências e a elaboração de saberes docentes

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    Nosso objeto de estudo é um projeto colaborativo Universidade-Escola-Diretorias de ensino, cujo foco era a formação de professores do ensino fundamental e o ensino de Ciências, mais especificamente a Física. No presente trabalho, entrevistamos professores que participaram do Projeto em questão e discutiremos as contribuições de um Projeto dessa natureza, relacionadas à elaboração de saberes docentes pelas professoras participantes. Consideramos especificamente saberes de dois tipos: saberes pedagógicos gerais e saberes pedagógicos de conteúdo. A pesquisa mostrou, por um lado, o potencial de um Projeto dessa natureza quanto à possibilidade de contribuir com as escolas participantes em diversos aspectos. Por outro lado, aponta a necessidade de revisão de vários outros, dentre eles, os ligados aos conteúdos específicos de Ciências

    The pinewood nematode, Bursaphelenchus xylophilus, in Madeira Island

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    The environmental conditions in Madeira Island are favorable for the presence and dissemination of the pinewood nematode (PWN), Bursaphelenchus xylophilus. Five hundred Pinus pinaster wood samples were collected in several forest areas and PWN was detected in 22.8 % of the samples. Bursaphelenchus xylophilus isolates from Madeira Island displayed the species-specific diagnostic characters. A morphological variation in the female tail terminus was detected. In most females, the tail presented a broadly rounded terminus and, occasionally, a digitate terminus with a terminal nipple-like extension resembling a mucro. PCR ITS-RFLP analysis revealed that Madeira Island isolates exhibited patterns specific to the species B. xylophilus and similar to virulent isolates. Amplified ITS regions were further sequenced and no genetic diversity was found for this genomic region among 17 Portuguese isolates (Madeira Island and Continental Portugal). Phylogenetic analysis revealed that Portuguese isolates grouped with isolates from China, Korea and one isolate from Japa

    Contextual reasons for emigrants’ electoral participation in home country elections: The Portuguese case

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    Although emigrants represent an increasing share of the electoral population in many democracies not much is known about their participation in home country elections. Aiming at contributing to fulfil this gap, this article longitudinally and exploratory analyses the contextual factors of Portuguese emigrants’ participation in national elections (1976-2015), a country with one of the highest emigration rates of EU today. First, it presents a longitudinal analysis of the electoral participation of Portuguese emigrants, and then analyses the conditions underlying levels of participation. By using aggregate data covering the main fifteen destination countries, this study compares institutional, socio-economic and political contextual factors for voting. Findings indicate that the lack of political participation of emigrants is first demonstrated by the very low registration rates, although it varies according to the country, and that voting methods and socio-economic factors in the destination country are the most relevant to explain voting in home country elections.info:eu-repo/semantics/acceptedVersio

    The Lessons from Libor for Detection and Deterrence of Cartel Wrongdoing

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    In late June 2012, Barclays entered into a $453 million settlement with UK and U.S. regulators due to its manipulation of Libor between 2005 and 2009. Among the agencies that investigated Barclays is the Department of Justice Antitrust Division (as well as other antitrust authorities and regulatory agencies from around the world). Participation in a price fixing conduct, by its very nature, requires the involvement of more than one firm. We are cautious to draw overly broad conclusions until more facts come out in the public domain. What we note at this time, based on public information, is that the Libor conspiracy and manipulation seems not to be the work of a rogue trader. Rather it seems to have been organized across firms and required the active knowledge of a number of individuals at relatively high levels of seniority among certain Libor setting banks. Collusion across firms is at the core of illegal antitrust behavior. The Supreme Court has deemed the pernicious effects of cartels so central to antitrust’s mission that it has stated that cartels are “the supreme evil of antitrust.” The involvement of more than one bank in such a cartel is a significant corporate governance failure due to the coordination that such a cartel would have required among the various cartel members. That the Libor cartel seems to have occurred in such a highly regulated industry after a wave of corporate governance reforms post-Enron and a push to greater internal compliance in the early 2000s is perhaps even more surprising. Yet, the very nature of what may have occurred regarding Libor manipulation, in hindsight, seems rather obvious. The rate did not move for over a year until the day before the financial crisis of 2009 hit. Also, quotes by the member banks that were submitted under seal moved simultaneously to the same number from one day to the next during that time period. Had any member bank that set Libor or indeed any antitrust authority undertaken an econometric screen, they would have detected these anomalies, undertaken a more in-depth investigation and discovered the wrongdoing. This essay explores the use of econometric screens as a tool to improve detection of potential price fixing cartel behavior as a method to police the firm from illegal behavior either by enforcement authorities or via firms themselves

    The Lessons from Libor for Detection and Deterrence of Cartel Wrongdoing

    Get PDF
    In late June 2012, Barclays entered into a $453 million settlement with UK and U.S. regulators due to its manipulation of Libor between 2005 and 2009. Among the agencies that investigated Barclays is the Department of Justice Antitrust Division (as well as other antitrust authorities and regulatory agencies from around the world). Participation in a price fixing conduct, by its very nature, requires the involvement of more than one firm. We are cautious to draw overly broad conclusions until more facts come out in the public domain. What we note at this time, based on public information, is that the Libor conspiracy and manipulation seems not to be the work of a rogue trader. Rather it seems to have been organized across firms and required the active knowledge of a number of individuals at relatively high levels of seniority among certain Libor setting banks. Collusion across firms is at the core of illegal antitrust behavior. The Supreme Court has deemed the pernicious effects of cartels so central to antitrust’s mission that it has stated that cartels are “the supreme evil of antitrust.” The involvement of more than one bank in such a cartel is a significant corporate governance failure due to the coordination that such a cartel would have required among the various cartel members. That the Libor cartel seems to have occurred in such a highly regulated industry after a wave of corporate governance reforms post-Enron and a push to greater internal compliance in the early 2000s is perhaps even more surprising. Yet, the very nature of what may have occurred regarding Libor manipulation, in hindsight, seems rather obvious. The rate did not move for over a year until the day before the financial crisis of 2009 hit. Also, quotes by the member banks that were submitted under seal moved simultaneously to the same number from one day to the next during that time period. Had any member bank that set Libor or indeed any antitrust authority undertaken an econometric screen, they would have detected these anomalies, undertaken a more in-depth investigation and discovered the wrongdoing. This essay explores the use of econometric screens as a tool to improve detection of potential price fixing cartel behavior as a method to police the firm from illegal behavior either by enforcement authorities or via firms themselves
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