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1.
Science ; 383(6687): 1062-1064, 2024 Mar 08.
Article de Anglais | MEDLINE | ID: mdl-38452091

RÉSUMÉ

As people get richer, and ecosystem services scarcer, policy-relevant estimates of ecosystem value must rise.


Sujet(s)
Écosystème , Politique de l'environnement , Humains , Conservation des ressources naturelles , Politique de l'environnement/économie , Analyse coût-bénéfice
2.
J Environ Manage ; 162: 179-89, 2015 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-26241933

RÉSUMÉ

Management strategies in rotational grazing systems differ in their level of complexity and adaptivity. Different components of such grazing strategies are expected to allow for adaptation to environmental heterogeneities in space and time. However, most models investigating general principles of rangeland management strategies neglect spatio-temporal system properties including seasonality and spatial heterogeneity of environmental variables. We developed an ecological-economic rangeland model that combines a spatially explicit farm structure with intra-annual time steps. This allows investigating different management components in rotational grazing systems (including stocking and rotation rules) and evaluating their effect on the ecological and economic states of semi-arid grazing systems. Our results show that adaptive stocking is less sensitive to overstocking compared to a constant stocking strategy. Furthermore, the rotation rule becomes important only at stocking numbers that maximize expected income. Altogether, the best of the tested strategies is adaptive stocking combined with a rotation that adapts to both spatial forage availability and seasonality. This management strategy maximises mean income and at the same time maintains the rangeland in a viable condition. However, we could also show that inappropriate adaptation that neglects seasonality even leads to deterioration. Rangelands characterised by higher inter-annual climate variability show a higher risk of income losses under a non-adaptive stocking rule, and non-adaptive rotation is least able to buffer increasing climate variability. Overall, all important system properties including seasonality and spatial heterogeneity of available resources need to be considered when designing an appropriate rangeland management system. Resulting adaptive rotational grazing strategies can be valuable for improving management and mitigating income risks.


Sujet(s)
Agriculture/méthodes , Bétail , Animaux , Climat , Conservation des ressources naturelles/méthodes , Analyse coût-bénéfice , Modèles théoriques , Saisons
3.
Horm Metab Res ; 37(11): 666-71, 2005 Nov.
Article de Anglais | MEDLINE | ID: mdl-16308834

RÉSUMÉ

During prolonged sepsis, impairment of glucose supply by the liver leads to hypoglycemia. Our aim was to investigate whether proinflammatory cytokine interleukin-6, a major mediator of the hepatic acute phase reaction, could contribute to this impairment by inhibiting hepatic glucose production stimulated by glucagon or isoproterenol in rat hepatocytes. Interleukin-6 inhibited the stimulation of glucose formation from glycogen by glucagon but not by isoproterenol in cultured rat hepatocytes. This was confirmed in the perfused rat liver. In cultured hepatocytes, the increase in cyclic adenosine-3',5'-monophosphate formation by glucagon was inhibited by interleukin-6, which was probably due to attenuation of glucagon binding to the glucagon receptor. The increase in cyclic adenosine-3',5'-monophosphate stimulated by isoproterenol was not affected by interleukin-6. However, the cytokine inhibited both expression of the key gluconeogenic control enzyme, phosphoenolpyruvate carboxykinase, stimulated by glucagon and isoproterenol. Thus, while increased glucose demand during the acute-phase reaction might initially be accomplished by catecholamine-mediated stimulation of glucose formation from glycogen, inhibition of gluconeogenesis by interleukin-6 may contribute to the impairment of glucose homeostasis during the prolonged acute phase reaction.


Sujet(s)
Glucagon/pharmacologie , Glucose/biosynthèse , Hépatocytes/métabolisme , Interleukine-6/pharmacologie , Isoprénaline/pharmacologie , Animaux , Cellules cultivées , AMP cyclique/biosynthèse , Glucagon/métabolisme , Mâle , Phosphoenolpyruvate carboxykinase (GTP)/antagonistes et inhibiteurs , Rats , Rat Wistar , Récepteurs au glucagon/métabolisme , Facteur de transcription STAT-3/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques
6.
Psychiatr Neurol Med Psychol (Leipz) ; 33(9): 565-72, 1981 Sep.
Article de Allemand | MEDLINE | ID: mdl-7302010

RÉSUMÉ

From the picture of the cerebral disturbances of movement, the basically possible psychic sequelae are derived and psychodiagnostic problems and possibilities for the appraisal of the developmental stage and the intelligence of early registered children with cerebral disturbances of movement are discussed.


Sujet(s)
Développement de l'enfant , Troubles psychomoteurs/diagnostic , Enfant d'âge préscolaire , Diagnostic différentiel , Allemagne de l'Est , Humains , Nourrisson , Tests psychologiques , Troubles psychomoteurs/rééducation et réadaptation
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