798 research outputs found

    Designing an Analytic Deliberative Process for Environmental Health Policy Making in the U.S. Nuclear Weapons Complex

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    Using a National Research Council Report as a centerpiece, Drs. Tuler and Webler evaluate the effectiveness of a conceptual approach to risk policy-making

    Public Participation in Hazard Management: The Use of Citizen Panels in the U.S.

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    After discussing the need for citizen participation in Risk management and a method of facilitating such participation as developed in Germany, the authors discuss and analyze its subsequent modification and use in a sewage sludge management project in New Jersey

    Organizing Public Participation: A Critical Review of Three Handbooks

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    Handbooks and guidebooks give advice to would-be practitioners on how to do public participation well. They offer a cookbook solution to the troubled official who is pressed to implement a state-of-the-art program, but is inexperienced in doing so. Although I have reservations about taking a cookbook approach too far, I also believe it does have a place in the field at the moment. In this review I attempt to build awareness about the availability of these handbooks and manuals. Doing so is an important step in promoting learning and the betterment of public participation. Better public participation can lead to a better state of public affairs. If we trust in the reasonableness of the publics--and I assert that the vast majority of us in this field do--then we also trust that better public participation also moves us closer to realizing the principles of sustainability and balance

    Beyond Science: Deliberation and Analysis in Public Decision Making

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    I agree very much with most of Carolyn Raffensperger’s argument. Understanding Risk does stand out for its willingness to admit that we need to rethink our assumptions about the privileged role that scientists and “experts” play in public decision making on topics of risk and environment. Involving publics in meaningful ways with scientists can make better science, but only if the scientists allow this to happen. I agree with Carolyn when she writes that this might require scientists engaging in inductive reasoning — some- thing many of them have been trained not to do! Surely the scientific method is powerful. Deductive reasoning is powerful. We do not need to abandon it in order to recognize that building a definition of the problem “from the ground up” might be a competent and politically expedient way to proceed. Still, I disagree that this is the main message to take from the report. The debate about why to involve lay people in public decision making may have matured, in a sense, via the status a National Research Council committee has, but Understanding Risk does not provide anything new to that debate

    Rolle von endothelialen Cytochrom-P450-Epoxygenasen in der Regulation der Angiogenese

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    Cytochrome P450 epoxygenases of the 2C family (CYP2C) are highly expressed in the endothelium and metabolize arachidonic acid to different regioisomers of epoxyeicosatrienoic acids (EET). They have a number of roles in the regulation of vascular tone and homeostasis by activating different signal transduction pathways and have recently been reported to be involved in proliferation and angiogenesis. However, the exact mechanisms by which epoxygenases regulate angiogenesis are still unclear. Therefore, the initial aim of the present study was to characterize the relevance of major signalling molecules that are involved in angiogenesis and to investigate possible signalling pathways involved. Initially the effect of CYP2C9 overexpression on expression levels of EphB4, a tyrosine kinase that plays a role in a number of developmental processes, was investigated. EphB4 protein expression was increased in CYP2C9 overexpressing cells without any effects on expression levels of its ligand ephrinB2. To clarify whether EphB4 is a critical determinant of CYP2C9-induced angiogenesis, endothelial cell sprouting was assessed using a collagen gel-based in vitro angiogenesis assay. Following transfection with EphB4 antisense or scrambled oligonucleotides, capillary-like structures were clearly present after 24 hours in cells overexpressing CYP2C9, while EphB4 downregulation abolished CYP2C9-induced sprouting. In addition stimulation of human umbilical vein endothelial cells with VEGF resulted in an increase in CYP2C expression and a subsequent increase of 11,12-EET production; an effect that was abolished by the CYP epoxygenases inhibitor MSPPOH as well as when cells were infected with a dominant negative mutant of AMPK. In vivo 11,12-EET treatment increased EphB4 expression in mesenteric arteries as well as in Matrigel plugs; an effect that was abolished when plugs were impregnated at the same time with small interfering RNA (siRNA) for EphB4. Furthermore, impregnation of Matrigel plugs with VEGF resulted in endothelial cell and smooth muscle cell recruitment into a Matrigel plug and this effect was mediated by CYP2C9-derived EETs as it was prevented by 14,15-EEZE. When infiltration of EET impregnated plugs with endothelial cells and pericytes/smooth muscle cells in vivo was compared to the effects seen in VEGF treated plugs, it was apparent that only EET treatment resulted in the formation of tube like structures that were covered by smooth muscle cells. Therefore, the final aim of the study was to further define the consequences of EET signalling in vivo as well as to characterize its physiological relevance. This hypothesis could be assessed by isolectin injection through the tail-vein where isolectin was taken up only by the EET-impregnated plug. Moreover ultrasound measurements revealed accumulation of contrast agent in EET impregnated plugs compared to control plugs. Taken together our findings emphasize that CYP2C plays a crucial role in the vessel formation process by modulating the effects mediated by two important control elements of the angiogenic response, namely VEGF and EphB4. CYP2C-derived EETs not only participate as second messengers in the angiogenic response, but have the potential to influence much more than angiogenesis by enhancing smooth muscle cell/pericyte recruitment to endothelial cell tubes to promote vascular maturation.Im nativen Endothel exprimierte Cytochrom P450 Epoxygenasen der 2C Familie (CYP2C) synthetisieren aus Arachidonsäure verschiedene Regioisomere der Epoxyeicosatriensäure (EET), welche eine wichtige Rolle bei der Regulation des vaskulären Tonus und der Homöostase spielen. Obwohl schon beschrieben wurde, dass Enzyme der CYP2C Familie an Prozessen der Proliferation und Angiogenese beteiligt sind, ist der genaue molekulare Mechanismus ihrer Wirkung noch weitestgehend ungeklärt. Deswegen war das primäre Ziel der vorliegenden Arbeit die Identifizierung von Signaltransduktionsmolekülen, die an der CYP-induzierten Angiogenese beteiligt sind, sowie die nachfolgende Charakterisierung möglicher daran beteiligten Signaltransduktionskaskaden. Zunächst wurde der Einfluss von CYP2C9 auf die Expression von EphB4, einer für eine Reihe von Entwicklungsprozessen wichtigen Tyrosinkinase, untersucht. In CYP2C9-überexprimierenden Zellen war die EphB4-Proteinexpression erhöht ohne einen Einfluss auf die Expression des Liganden ephrinB2 zu haben. Dieser Effekt war EET-vermittelt und konnte durch den CYP Epoxygenase Inhibitor MSPPOH, den PI3K Inhibitor LY 294002 oder gleichzeitige Transfektion mit einer dominant negativen Akt Mutante aufgehoben werden. Des weiteren führte die Stimulation von Zellen humaner Nabelschnurvenen mit VEGF sowohl zu einer Steigerung der CYP2C-Expression als auch zur vermehrten 11,12-EET Bildung; ein Effekt, der sowohl durch den Epoxygenase Inhibitor MSPPOH als auch durch gleichzeitige Infektion der Zellen mit einer dominant negativen Mutante der AMPK hemmbar war. Darüber hinaus sollte die physiologische Bedeutung dieser in vitro Befunde in vivo weiter konkretisiert werden und die Relevanz für den Angiogeneseprozess erörtert werden. Ein entscheidender Schritt für die Blutgefässbildung ist die Proliferation und Differenzierung von Endothelzellen, was zur Bildung von vaskulären röhrenartigen Gebilden (engl. „Tubes“) führt. Es konnte gezeigt werden, dass CYP2C an der VEGF-, nicht aber an der bFGF-vermittelten Ausbildung dieser Strukturen beteiligt ist, da der EET-Antagonist 14,15-EEZE beispielsweise in bFGF-behandelten Zellen keinerlei Effekt hatte. Auch in vivo führte die Imprägnierung eines Matrigel Plugs mit VEGF zur Wachstumsfaktor-spezifischen Rekrutierung von Endothel- als und in geringerem Ausmass auch zur Rekrutierung von glatten Muskelzellen bzw. Perizyten. Des weitern sollte der Einfluss von EETs auf die Reifung von Gefässen untersucht werden. Die Einwanderung von Endothelzellen und Pericyten/glatten Muskelzellen in vivo in einen EET-impregnierten Plug war vergleichbar mit der in VEGF-behandelte Plugs. Aber nur die EET-Behandlung führte zur Ausbildung von vaskulären „Tubes“, die auch mit glatten Muskelzellen verkleidet waren. Ebenso wurde durch die Schwanzvene von Mäusen injiziertes Isolektin nur durch die EET-impregnierten Plugs, nicht aber durch VEGF-imprägnierte Plugs aufgenommen. Weiterhin konnte durch Ultraschallmessungen ein erhöhtes Anfluten von Kontrastmittel im EET-behandelten Plug im Vergleich zur Kontrolle verzeichnet werden, was ein weiterer Hinweis für die Ausbildung von perfundierten, funktionsfähigen Gefässstrukturen ist. Zusammenfassend lässt sich sagen, dass EETs über die Modulation zweier wichtiger Stellglieder der angiogenen Antwort, nämlich VEGF und EphB4, eine Rolle bei der Regulation von Rezeptoren und Signaltransduktionsmolekülen spielen, die essentiell für die normale Blutgefässentwicklung und Gefässreifung sind. Die von CYP2C-stammenden EETs sind nicht nur als sekundäre Botenstoff an der angiogenen Antwort, die durch eine Vielzahl von Faktoren ausgelöst wird, beteiligt, sondern haben zudem das Potential sowohl Endothelzellen als auch Perizyten/glatte Muskelzellen z

    How To Do Environmental Decision Making: Varying Perspectives on the U.S. National Research Council’s Understanding Risk Report

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    There are two reasons why public participation in decision making about risk and environmental management persists as an important, timely issue. First, people still disagree about whether lay people should be involved in these decisions at all. This is the question of “why?” Second, there is uncertainty about how to best involve, meaningfully, diverse lay people and scientists in an efficient, effective decision making process. This is the question of “how?

    Science Communication and Vernal Pool Conservation: A Study of local decision maker attitudes in a knowledge-action system

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    designing and implementing boundary management strategies, and highlights the complexities of direct engagement between scientists and policymakers and the implications of that engagement for scientists and their academic institutions. We draw from a case study conducted in Maine to argue that there are contexts in which the need arises for scientists to manage and span the science-policy boundary. The complexities involved in preparing scientists to engage more thoroughly in policy activities and the challenges in garnering institutional support for advancing the participation of scientists in boundary spanning activities are explored

    Public Participation: Relevance and Application in the National Park Service

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    Government agencies are under increased pressure to conduct policy planning and decision-making activities in more transparent and inclusive ways. The clear trend is toward broader and more frequent public involvement and collaboration. For example, the U.S. Fish and Wildlife Service organizes deliberation among stakeholders for endangered species recovery planning (Clark et al. 1994, Clark and Wallace 1998). The Army Corps of Engineers has experimented with a variety of collaborative problem solving and public participation techniques (Creighton et al. 1998). The U.S. Forest Service continues implementation of a variety of approaches to public participation, including “collaborative learning” and adaptive management planning (Gericke et al. 1992, Sarvis 1994, Shindler and Creek 1997). At its nuclear weapons production sites where cleanup is the major issue, the Department of Energy has set up site-specific advisory boards (Bradbury and Branch 1999). Throughout many parts of the federal government, and within state governments as well, involvement of stakeholders and citizens is becoming a priority issue

    PromotingClimate Change Awareness and Adaptive Planning in Atlantic Fisheries Communities using Dialogue-based Participatory Vulnerability Analysis, Mapping, and Collaborative Systems Dynamic Modeling

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    The goals for the proposed project are twofold: • First, the project will improve understandings of how a changing climate will affect fishing communities’ abilities to maintain marine fisheries and the local economies historically dependent upon them. • Second, the project will investigate the role of a structured dialogue and participatory modeling process to support decision makers in fishing communities addressing consequences, vulnerabilities, and adaptive strategies in a context of climate stressors

    A agricultura familiar como agente produtora do espaço rural no município de Chapecó-SC

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    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-graduação em GeografiaA compreensão da realidade do espaço rural exige conhecimentos sobre a dinâmica local, assim como os processos que influenciam nas decisões dos agricultores. As constantes mudanças econômicas atuam sobre o espaço rural, proporcionando usos distintos, condicionando os agricultores familiares a se adaptarem. Desta forma, "novas" alternativas econômicas surgem para o desenvolvimento da agricultura familiar. Com base em uma metodologia fundamentada em estudos bibliográficos e de campo a presente pesquisa se propõe a compreender as transformações ocorridas no espaço rural de Chapecó - SC. A análise será focada na agricultura familiar e procurará compreender a dinâmica dos estabelecimentos de acordo com as atividades realizadas, assim como, suas relações com o mercado, e a importância das novas atividades para a revitalização do espaço rural. Igualmente observou-se uma diversidade de realidades vivenciadas pelos agricultores locais, entre os quais se destacam os agricultores em situação de fragilidade econômica e social. Os resultados da pesquisa demonstram que além das atividades agropecuárias já consolidadas como a suinocultura, o milho, feijão e a soja, os agricultores familiares passaram também a se dedicar a outras atividades para implementar rendas como: agroturismo, fruticultura, piscicultura, apicultura, agroecologia, agroindústrias familiares e a ovinocultura. Estas atividades têm gerado maior dinamismo econômico às propriedades, os retornos financeiros têm motivado os agricultores familiares. No entanto, apesar de existir projetos que buscam fortalecer a agricultura familiar, ainda persistem muitos problemas, em que diversos produtores encontram-se estagnados e excluídos do mercado. Deste modo, a sobrevivência do agricultor familiar depende de constantes desafios que precisam ser vencidos diariamente
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