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1.
Water Sci Technol ; 67(11): 2651-60, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23752402

RESUMO

Integrated Water Resource Management (IWRM) aims at finding practical and sustainable solutions to water resource issues. Research and practice have shown that innovative methods and tools are not sufficient to implement IWRM - the concept needs to also be integrated in prevailing management paradigms and institutions. Water governance science addresses this human dimension by focusing on the analysis of regulatory processes that influence the behavior of actors in water management systems. This paper proposes a new methodology for the integrated analysis of water resources management and governance systems in order to elicit and analyze case-specific management paradigms. It builds on the Management and Transition Framework (MTF) that allows for the examination of structures and processes underlying water management and governance. The new methodology presented in this paper combines participatory modeling and analysis of the governance system by using the MTF to investigate case-specific management paradigms. The linking of participatory modeling and research on complex management and governance systems allows for the transfer of knowledge between scientific, policy, engineering and local communities. In this way, the proposed methodology facilitates assessment and implementation of transformation processes towards IWRM that require also the adoption of adaptive management principles. A case study on flood management in the Tisza River Basin in Hungary is provided to illustrate the application of the proposed methodology.


Assuntos
Conservação dos Recursos Naturais/métodos , Modelos Teóricos , Recursos Hídricos , Hungria , Rios
2.
Water Sci Technol ; 52(6): 115-24, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16304943

RESUMO

Uncertainty is an increasingly important concern when trying to manage complex systems of interrelated natural resources. Scientific knowledge or necessary information may be lacking or incomplete. Additionally, the multiple and interdependent users of those resources may diverge in defining what really is at stake. When they frame issues in very different ways, ambiguity results, i.e., the existence of two or more equally plausible interpretation possibilities. Environmental management in these conditions implies a shift in attention from solving clearly delineated problems to continuous negotiating and tuning between different actors and expertise domains. This requires dealing with the frame differences in a reciprocal way by mutually acknowledging frames and connecting them. Some or all parties will have to revise, enlarge or reframe the way they relate to the issues and to each other, in order to support mutual understanding and common action. The contribution of experts does not consist then in providing total predictability nor in predefining issues and solutions, but in supporting a joint learning and negotiation process among different actors and in feeding this process with relevant information. Behavioural simulations may play an important function to stimulate multi-actor learning and negotiation processes.


Assuntos
Conservação dos Recursos Naturais , Incerteza , Agricultura , Comunicação , Participação da Comunidade , Equador , Mineração
3.
Water Sci Technol ; 48(1): 57-65, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12926621

RESUMO

The technology of urine separation and the recycling of anthropogenic nutrients as fertilizer in agriculture are considered as major innovations to improve the sustainability of today's urban wastewater management. The acceptance of consumers will be key for the introduction of the new technology. Citizens will have to make important decisions in their role as tenants and owners of houses and as consumers buying products fertilized with urine. Consumer attitudes towards the new technology were explored in a number of citizen focus groups in Switzerland. Focus groups are deliberate, moderated group discussions with informed citizens on a certain topic. The information was provided by a computer based information system specifically designed for this purpose. The acceptance of individual citizens for the new technology proved to be quite high. The majority of the citizens expressed their willingness to move into an apartment with NoMix toilets and to buy food fertilized with urine. However, they were not willing to accept additional financial costs or efforts. Arguments related to long-term sustainability (closing nutrient cycles) were of less importance than arguments that relate directly to the effects of micropollutants on human and ecosystem health. For the introduction of the new technology on a wide scale it will thus be crucial to explore the fate and effects of micropollutants.


Assuntos
Agricultura , Conservação dos Recursos Naturais , Opinião Pública , Urina/química , Participação da Comunidade , Ecossistema , Grupos Focais , Humanos , Saúde Pública , Transferência de Tecnologia , Eliminação de Resíduos Líquidos
4.
Water Sci Technol ; 43(5): 319-26, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11379148

RESUMO

An analysis of the characteristic goals, strategies and rules of behavior of relevant stakeholders allows the efficacy and potential risks of past and current engineering and management concepts to be estimated. The study is driven by the observable shift from security to cost-centered strategies by water utilities and the difficulties of balancing technical and financial needs in an uncertain future. Its benefits include a methodology with a twofold result. With the aid of domain knowledge from experts involved in a participatory process, the interactions of a subset of stakeholders are quantified and documented in a rule catalog. This leads to an improved understanding of their decision-making rules. An agent-based model comprising these stakeholders' rules of behavior in subsequently development. Once the model is validated with data sets from a real utility, multiple-scenario testing helps to explore different strategies and can be used to generate ideas for developing flexible management and design schemes. Despite the complexity of the system described, simple model rules which are repeated annually can replicate the general development of both capacity and cost-related parameters. Scenario simulations show the effects of different management strategies on key parameters such as capacity, water price and financial debt.


Assuntos
Tomada de Decisões , Relações Interinstitucionais , Modelos Teóricos , Abastecimento de Água , Cidades , Administração Financeira , Humanos , Política Organizacional , Medição de Risco
5.
Peptides ; 15(7): 1223-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7854973

RESUMO

NMR spectroscopy is a useful tool for monitoring multiple intermediate metabolic pathways in different organs in intact animals and humans. We report the effect of the somatostatin analogue octreotide on the fate of 13C-labeled glucose administered to fasted and well-fed rats as determined by NMR spectroscopy. The production of 13C-labeled glycogen and its subsequent breakdown after the end of infusion was identified with a time resolution of 7 min. Hepatic glycogen synthesis was not different between control and octreotide-treated animals but persisted for 15 min after the end of the infusion only in control animals. Glycogenolysis, however, was initiated immediately after the end of infusion in octreotide-treated animals where the half-life of glycogen was 40 min compared with 68 min in control animals. However, once initiated, the rate of glycogenolysis was not significantly altered by octreotide. Although octreotide had no effect on glucose signal intensities in fasted animals, 13C glucose signals were more intense in octreotide compared with control well-fed animals. In conclusion, octreotide alters rat hepatic metabolism by accelerating the onset of glycogenolysis and stimulating glucose accumulation without significantly interfering with glycogen synthesis.


Assuntos
Glicogênio Hepático/biossíntese , Fígado/efeitos dos fármacos , Fígado/metabolismo , Octreotida/farmacologia , Animais , Glucose/metabolismo , Humanos , Técnicas In Vitro , Glicogênio Hepático/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley
7.
Biol Chem Hoppe Seyler ; 368(3): 205-14, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3593540

RESUMO

13C-NMR spectroscopy was used as a noninvasive approach to study the metabolism of [1,3-13C]octanoate in rat liver. Using a properly adjusted surface coil a liver selection of better than 90% was achieved in the intact animal without abdominal surgery. After infusion of [1,3-13C]octanoate via the jugular vein different patterns of metabolites were observed depending on the physiological state of the rat. In the fasted animal, the major metabolites were those of the Krebs cycle while in the diabetic animal ketogenic end products were predominant. As a fatty acid of medium chain length octanoate is imported into the inner mitochondrial space without control by the carnitine acyl transferase system. Hence, the metabolic differences observed between diabetic and fasted rats result from an intramitochondrial control mechanism. The in vivo 13C-NMR results therefore support previous biochemical in vitro studies which concluded that a major control of ketone body production occurs in the inner mitochondrial space, presumably via the redox potential of the liver. As an unexpected result, 13C-NMR provides evidence for the transitory esterification of the infused 13C-labeled octanoic acid. The corresponding 13C-NMR chemical shifts are typical for glycerides.


Assuntos
Caprilatos/metabolismo , Corpos Cetônicos/biossíntese , Fígado/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Jejum , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Endogâmicos
8.
Biochemistry ; 25(22): 6799-807, 1986 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-3801392

RESUMO

The hormonal regulation of ketogenesis in the liver of living rat has been studied noninvasively with 13C nuclear magnetic resonance. The protocol involved the use of a surface coil that was placed on the skin of the rat, directly over the normal location of the liver. Signals from superficial tissue were suppressed with a 180 degrees pulse at the center of the coil. A resolution of 0.6 ppm was obtained in the 13C NMR spectra at 20.1 MHz, which was equal to or better than that observed in experiments where the liver was surgically exposed and surrounded with radiofrequency coil. The spatial selection for the liver was better than 90%, with extrahepatic adipose tissue contributing only a very small amount of signal. The metabolic activities of the liver were investigated by infusion of 13C-labeled butyrate in the jugular vein of the anesthetized rat. The rate of butyrate infusion was chosen to be close to the maximum oxidative capacity of the rat liver, and the 13C signal intensities were enhanced by using doubly labeled [1,3-13C]butyrate as a substrate. Different 13C NMR spectra and hence different metabolites were observed depending on the hormonal state of the animal. In the fasted rat, the most intense 13C signal came from the end product of the Krebs cycle, namely, HCO3, with additional resonances from glutamine and glutamate. Weak resonances of the ketone bodies 3-hydroxybutyrate and acetoacetate could also be detected and allowed an evaluation of the "redox state" of the in vivo liver.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Butiratos/metabolismo , Corpos Cetônicos/biossíntese , Fígado/metabolismo , Animais , Ácido Butírico , Isótopos de Carbono , Diabetes Mellitus Experimental/metabolismo , Jejum , Gluconeogênese , Espectroscopia de Ressonância Magnética/métodos , Masculino , Ratos , Ratos Endogâmicos
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