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Possibilities and problems with the use of models as a communication tool in water resource management 总被引:2,自引:1,他引:1
Politicians and policy-makers, as well as modellers, often nurses an expectation that model derived results is an objective
source of information that can be used to support decisions. However, several prerequisites have to be dealt with in order
to ensure that models can be used as legitimate and efficient tools in water resource management. Based on empirical material
from recent studies on the use of models in stakeholder dialogues, mainly focusing on catchment nutrient transport, two central
problems are identified: (a) Models are laden with choices and thus depend on assumptions and priorities of modellers. (b)
There are several factors that influence ability and willingness of stakeholders (as information recovers) to criticize or
accept results of the modelling exercise. Recognized factors likely to influence stakeholders' acceptance of model derived
results include issues at stake, stakeholders' ability to criticize model derived information, and their trust in the institutions
that have developed or applied the used models. Identified prerequisites for successful use of models in integrated water
resource management include: consideration of user relevance, awareness of and preparedness to handle constraints linked to
communication of model-based results, transparency of used models and data and of involved uncertainties, mutual respect between
experts and stakeholders and between involved stakeholder groups, a robust institutional network, and sufficient time for
dialogues. Development and use of strategies for participatory modelling, based on a continuous dialogue between experts and
stakeholders is recommended as a way to facilitate that the prerequisites for a successful use of models in water resource
management are fulfilled. 相似文献
24.
The stability of cisplatin and its monohydrated complex has been studied in blood, plasma and plasma ultrafiltrate at 37 degrees C (pH 7.4). Intact cisplatin and the monohydrated complex were determined by liquid chromatography with post-column derivatization. The half lives for cisplatin and the monohydrated complex were 1.43 +/- 0.03 h (SEM) and 0.36 +/- 0.03 h (SEM), respectively, in blood and 0.88 +/- 0.05 h (SEM) and 0.26 +/- 0.02 h (SEM), respectively, in plasma. The compounds were unstable at -25 degrees C (t1/2 for cisplatin was 52 +/- 5 h (SEM) and for the monohydrated compound 26 +/- 2 h (SEM)), but at -70 degrees C both compounds were stable for at least 3 weeks. The monohydrated complex was found to be formed to a small extent when cisplatin was added to plasma (37 degrees C, pH 7.4). A sampling procedure using centripetal ultrafiltration of whole blood was evaluated and found applicable if the samples were stored at 0 degree C and ultracentrifuged within 1 h. 相似文献
25.
F Hammarqvist B Westman CE Leijonmarck K Andersson J Wernerman 《Canadian Metallurgical Quarterly》1996,119(4):417-423
A number of studies have localized CGRP to nerves in the cornea and iris, and it is thought that CGRP, along with other neuropeptides, is involved in pain sensation. It is also possible that CGRP could mediate trophic influences between nerve endings and corneal epithelium. This investigation utilized an in vitro rabbit corneal whole mount preparation to study the effect of topical 2.5 microM CGRP application on epithelial wound healing rates of 5 mm diameter epithelial wounds. CGRP (2.5 microM) was applied topically to 5 mm epithelial wounds at 0, 4, 16, 20, 24, 28, 40, 44, 48, 52, 56, 64, 68, and 72 hours after wounding and healing was visualized with fluorescein. CGRP was found to increase the epithelial wound healing rate by 25%, from 51 +/- 3 microns/hr for the control corneas, to 64 +/- 2 microns/hr for CGRP-treated corneas (mean +/- standard error, n = 10). Histological examination of the corneas following healing showed that the epithelium of the CGRP-treated corneas healed in a similar manner as in the control corneas. These findings may have clinical utility for the understanding and treatment of corneal and other epithelial wounds. 相似文献
26.
Life table studies were performed in 1996 with Aedes aegypti (L.) during the low (cool/dry) and high (hot/rainy) dengue virus transmission seasons in Puerto Rico. Mated adult females from field-collected pupae were placed individually in cages and divided into 2 treatment groups: one was fed only human blood and the other human blood plus a 10% sucrose solution. Survival and number of eggs laid were recorded daily for each female. During both seasons, age specific survivorship was higher for the blood plus sugar group, groups fed only human blood had higher reproductive outputs (mx), and net replacement rates (Ro) for blood only groups were higher than for those fed blood plus sugar. Intrinsic rates of growth (r) were the same for both treatments during the low (cool/dry) transmission season, but higher for the blood-only treatment during the high (hot/rainy) transmission season. Our results indicate that feeding on only human blood provides an evolutionary advantage to Ae. aegypti females in Puerto Rico. These results are similar to those from an earlier study carried out with Ae. aegypti in Thailand; the advantage of feeding on human blood does not seem to be restricted to a particular geographic region. We also found that the benefits associated with human feeding persist through epidemiologically different times of the year. We conclude that feeding on human blood is reproductively beneficial for Ae. aegypti, which may increase their contact with human hosts, and therefore may influence their vectorial capacity for dengue viruses through frequent feeding on blood. 相似文献
27.
As a complementary modality, therapeutic touch is gaining increasing recognition. Not only are nurses incorporating therapeutic touch into their daily patient care, but patients also are requesting this healing modality. Nurse leaders also use this nursing intervention to weave their vision of healing into their managerial role. 相似文献
28.
LK Malendowicz C Macchi GG Nussdorfer A Markowska 《Canadian Metallurgical Quarterly》1996,11(3):641-645
The effects of a prolonged administration of bradykinin (BK) and/or D-Arg, [Hyp3, D-Phe7]-BK, a specific antagonist of BK receptors (BK-A) (daily subcutaneous injections of 4 nmol/rat for 6 days) on the function of the pituitary-adrenocortical axis were investigated. BK did not change plasma aldosterone concentration (PAC), but markedly lowered that of corticosterone (PBC) and consequently induced a compensatory hypersecretion of ACTH by the pituitary gland. BK-A did not apparently affect the function and growth of the adrenal gland, but, when administered together with BK, markedly raised both PAC and PBC, and provoked a significant atrophy of the adrenal gland, probably due to loss of parenchymal cells. Taken together, these rather puzzling findings do not appear to provide clear evidence for the involvement of BK in the physiological regulation of adrenocortical growth and steroidogenic capacity in rats. 相似文献
29.
AV Susekov MG Tvorogova GG Arabidze VV Kukharchuk 《Canadian Metallurgical Quarterly》1998,70(9):57-61
AIM: The study of the hypolipidemic efficiency, safety and tolerance of ciprofibrate (lipanor) in therapy of atherogenic hyperlipoproteinemia. MATERIALS AND METHODS: The trial included 14 hypertensive postmenopausal females, 14 patients with diabetes mellitus type II, 14 males with coronary heart disease and primary hyperlipoproteinemia (total cholesterol > 6.5 mmol/l, triglycerides < 4.5 mmol/l under low-cholesterol diet). Lipanor was given for 12 weeks in a daily single dose 100 mg in the morning. Lipids and other biochemical indices were measured in a fasting state after 1 and 3 months of lipanor treatment. RESULTS: After 1 month of lipanor treatment there was a 22-30%, 24-49% decrease in the level of low-density lipoprotein cholesterol, triglycerides, respectively. High-density lipoprotein cholesterol increased by 16%. The hypolipidemic effect of lipanor persisted for 3 months during which triglycerides continued to fall (up to 38.5%). Lipanor was well tolerated, only one patient with diabetes mellitus had hyperactivity of creatine phosphokinase manifesting with clinical symptoms (the drug was discontinued). 3 patients developed mild side effects. Alkaline phosphatase activity inhibited in all the groups by 25-41%. CONCLUSION: Lipanor is a highly effective, safe hypolipidemic drug with good tolerance. It can be recommended for correction of atherogenic hyperlipoproteinemia in patients at high risk of atherosclerosis progression. 相似文献
30.