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1.
Proc Natl Acad Sci U S A ; 109(19): 7156-61, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22509036

RESUMO

All human-environment systems adapt to climate and its natural variation. Adaptation to human-induced change in climate has largely been envisioned as increments of these adaptations intended to avoid disruptions of systems at their current locations. In some places, for some systems, however, vulnerabilities and risks may be so sizeable that they require transformational rather than incremental adaptations. Three classes of transformational adaptations are those that are adopted at a much larger scale, that are truly new to a particular region or resource system, and that transform places and shift locations. We illustrate these with examples drawn from Africa, Europe, and North America. Two conditions set the stage for transformational adaptation to climate change: large vulnerability in certain regions, populations, or resource systems; and severe climate change that overwhelms even robust human use systems. However, anticipatory transformational adaptation may be difficult to implement because of uncertainties about climate change risks and adaptation benefits, the high costs of transformational actions, and institutional and behavioral actions that tend to maintain existing resource systems and policies. Implementing transformational adaptation requires effort to initiate it and then to sustain the effort over time. In initiating transformational adaptation focusing events and multiple stresses are important, combined with local leadership. In sustaining transformational adaptation, it seems likely that supportive social contexts and the availability of acceptable options and resources for actions are key enabling factors. Early steps would include incorporating transformation adaptation into risk management and initiating research to expand the menu of innovative transformational adaptations.


Assuntos
Adaptação Fisiológica , Mudança Climática , Clima , Conservação dos Recursos Naturais/métodos , África , Ecossistema , Europa (Continente) , Humanos , América do Norte
3.
J Am Soc Echocardiogr ; 19(9): 1158-64, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16950471

RESUMO

OBJECTIVES: We defined the effects of the operative (OP) state and phenylephrine challenge on the assessment of mitral regurgitation (MR) severity. METHODS: In all, 57 patients underwent transesophageal echocardiographic assessment of MR severity pre-OP (PREOP) and intra-OP. MR severity was assessed PREOP under conscious sedation and intra-OP with general anesthesia, before and after hemodynamic manipulation with vasoactive agents, to match intra-OP and PREOP transesophageal echocardiographic mean arterial blood pressures. RESULTS: Intra-OP MR and mean arterial pressure were less than PREOP in 27 patients (both P < .001). When PREOP and OP blood pressures were matched using phenylephrine, there was no significant difference in MR severity between the two states (P = 1.0). Nonetheless, MR severity was still underestimated in 6 patients and overestimated in 7 patients intra-OP. CONCLUSIONS: Intra-OP transesophageal echocardiography underestimates MR severity. Phenylephrine reduces, yet does not eliminate, intra-OP underestimation of MR severity.


Assuntos
Ecocardiografia Transesofagiana/métodos , Cuidados Intraoperatórios/métodos , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Fenilefrina , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Vasoconstritores
4.
Proc Natl Acad Sci U S A ; 100(14): 8068-73, 2003 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-12819346

RESUMO

Sustainable development exhibits broad political appeal but has proven difficult to define in precise terms. Recent scholarship has focused on the nature of a sustainability transition, described by the National Research Council as meeting the needs of a stabilizing future world population while reducing hunger and poverty and maintaining the planet's life-support systems. We identify a small set of goals, quantitative targets, and associated indicators that further characterize a sustainability transition by drawing on the consensus embodied in internationally negotiated agreements and plans of action. To illustrate opportunities for accelerating progress, we then examine current scholarship on the processes that influence attainment of four such goals: reducing hunger, promoting literacy, stabilizing greenhouse-gas concentrations, and maintaining fresh-water availability. We find that such analysis can often reveal "levers of change," forces that both control the rate of positive change and are subject to policy intervention.


Assuntos
Conservação dos Recursos Naturais , Animais , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Escolaridade , Objetivos , Efeito Estufa , Humanos , Fome , Renda , Cooperação Internacional , Motivação , Política Pública , Mudança Social , Problemas Sociais , Abastecimento de Água
5.
Proc Natl Acad Sci U S A ; 100(14): 8062-7, 2003 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-12829798

RESUMO

How do long-term global trends affect a transition to sustainability? We emphasize the "multitrend" nature of 10 classes of trends, which makes them complex, contradictory, and often poorly understood. Each class includes trends that make a sustainability transition more feasible as well as trends that make it more difficult. Taken in their entirety, they serve as a checklist for the consideration of global trends that impact place-based sustainability studies.


Assuntos
Conservação dos Recursos Naturais/tendências , Agricultura/tendências , Animais , Comércio/tendências , Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema , Emigração e Imigração , Meio Ambiente , Poluição Ambiental , Efeito Estufa , Direitos Humanos/tendências , Humanos , Renda/tendências , Expectativa de Vida/tendências , Oceanos e Mares , Dinâmica Populacional , Pobreza/tendências , Mudança Social , Tecnologia/tendências , Árvores , Guerra , Abastecimento de Água
8.
Science ; 220: 378-84, Apr. 1983. ilus, Tab
Artigo em En | Desastres | ID: des-2403
9.
Massachusetts; U.S. The Massachusetts Institute of Technology; 1977. 331 p. ilus, mapas, tab, graf.
Monografia em En | Desastres | ID: des-13444
10.
Colorado; University of Colorado. Institute of Behavioral Science; 1977. 169 p. tab.(Program on Technology, Environment and Man, No.25).
Monografia em En | Desastres | ID: des-9998
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