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261.
262.
Nicolas Le Corre Ingrid Peuziat Louis Brigand Guillaume Gélinaud Catherine Meur-Férec 《Environmental management》2013,52(4):780-791
Disturbance to wintering birds by human recreational activities has become a major concern for managers of many natural areas. Few studies have examined how recreationists perceive their effects on birds, although this impacts their behavior on natural areas. We surveyed 312 users on two coastal ornithological sites in Brittany, France, to investigate their perception of the effects of human activities on wintering birds. The results show that the awareness of environmental issues and knowledge of bird disturbance depends on the socioeconomic characteristics of each user group, both between the two sites and within each site. Results also indicate that, whatever the site and the user group, the vast majority of the respondents (77.6 %) believed that their own presence had no adverse effects on the local bird population. Various arguments were put forward to justify the users’ own harmlessness. Objective information on recreationists’ awareness of environmental issues, and particularly on their own impact on birds, is important to guide managers in their choice of the most appropriate visitor educational programs. We recommend developing global but also specific educational information for each type of user to raise awareness of their own impact on birds. 相似文献
263.
René Rossi Eric Indelicato Walter Bolli 《International journal of occupational safety and ergonomics》2004,10(3):239-245
The aim of this study was to analyse the transfer of steam through different types of textile layers as a function of sample parameters such as thickness and permeability. In order to simulate the human body, a cylinder releasing defined amounts of moisture was also used. The influence of sweating on heat and mass transfer was assessed. The results show that in general impermeable materials offer better protection against hot steam than semi-permeable ones. The transfer of steam depended on the water vapour permeability of the samples, but also on their thermal insulation and their thickness. Increasing the thickness of the samples with a spacer gave a larger increase in protection with the impermeable samples compared to semi-permeable materials. Measurements with pre-wetted samples showed a reduction in steam protection in any case. On the other hand, the measurements with a sweating cylinder showed a beneficial effect of sweating. 相似文献
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We assessed the effects of anoxia exposure and recovery on glycogen synthesis and mobilization, glucose uptake, and on the enzymes that control carbohydrate metabolism in the hepatopancreas of Chasmagnathus granulata crabs receiving either a carbohydrate-rich (HC) or a high-protein diet (HP). In both dietary groups, anoxia led to a reduction in glucose uptake and in glycogen synthesis, and to an increase in hepatopancreas glycogen mobilization and in hemolymph glucose concentration. During the first 4 h of exposure to anoxia, total glycogen phosphorylase (GPT) and a form activity increased in HP and HC crabs, leading to a decrease in hepatopancreas glycogen concentration. During recovery, HP and HC crabs rapidly restored the hemolymph glucose levels to pre-anoxia concentrations. In HC crabs, incorporation of 14C from glucose into glycogen increased gradually after 12 h in normoxia, leading to restoration of glycogen concentration. Also during recovery, the ratio of glycogen synthase I (GSI) to glycogen phosphorylase a (GPa) increased in the HC group. In turn, recovering HP crabs had two peaks of glycogen synthesis, related with two peaks in the ratio of GSI to GPa. Consequently, no mobilization of 14C-glycogen occurred in recovering HP animals. Anoxia in C. granulata induces a marked decrease in the synthesis of carbohydrate reserves that is accompanied by an increase in glycogen mobilization and in circulating glucose levels. During the recovery period, there is an activation of endergonic processes which cause a decrease in hemolymph glucose levels. In C. granulata, glycogen metabolism seems to be controlled by the ratio of the GSI form to the GPa form. In field conditions, theses changes in the metabolic pattern may result from environmental PO2 availability. In the winter, C. granulata stays in its holes, where environmental PO2 falls to zero. The carbohydrate or protein content of the diets administrated to the crabs seem to induce different metabolic adjustments during anoxia and recovery. 相似文献
268.
Kalliopi?SapountzakiEmail author Louis?Wassenhoven 《Environment, Development and Sustainability》2005,7(4):433-452
The paper focuses on the example of a local island community in Greece, to illustrate the difficulties of effective consensus
building, in support of sustainable policies. In the first section the issue of sustainability and the importance of participation
are discussed, before moving to a brief outline of the nature of participation and its sources since the 1960s. It follows
an analysis of the epistemological framework of consensus building process which is considered as the most integrated and
sophisticated version of participatory planning. This analysis serves as a background for judging the appropriateness of consensus
building for the resolution of an environmental problem harassing a Greek island community. It is about the problem of water
availability and management in the small Aegean island of Leros. The paper shows how illegal practices in the use of water,
administrative fragmentation and confusion over knowledge of the problem and its solutions lead to divisions in the stakeholder
groups and to obstacles in the way of participation. The intrinsic problems embedded in Greek (and probably not alone) society
and political culture, which prevent collective action and participation, account in part for the anticipated risk of unwelcome,
illegitimate outcomes of a potential consensus building process. Nevertheless, if communicative planning is to gain universal
acceptance, it should first resolve some critical theoretical and practical shortcomings related to its normative, ethical
and philosophical assumptions.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
269.
Michel Potier Jocelyne Cousineau Lorraine Michaud Max Zolinger Serge B. Melançon Louis Dallaire 《黑龙江环境通报》1986,6(6):429-436
The intestinal microvilli of fetal origin in human amniotic fluid were purified by Ca2+ precipitation of contaminating organelles followed by differential centrifugation of microvillar membranes. In the purified preparation, the specific activity of the microvillar marker-enzymes maltase and sucrase increased about 77-fold over that in cell-free amniotic fluid. Significant contamination of the purified preparation by endoplasmic reticulum (microsomes) and lysosomes was ruled out on the basis of a low content of the marker enzymes glucose-6-phosphatase (microsomes) and acid phosphatase (lysosomes). Amniotic fluid microvilli contain typical enzymes of the fetal intestine including maltase, sucrase, trehalase, alkaline phosphatase and γ-glutamyltransferase, and their morphology by electron microscopy resembles that of vesiculated intestinal microvilli. Prenatal detection of genetic diseases due to a deficiency of a protein expressed in these membranes or associated to abnormal microvilli seems feasible. 相似文献
270.
Grant A. Mitchell MD Cornelis Jakobs K. Michael Gebson Marie-France Robert Alberto Burlina Carlo Dionisi-Vici Louis Dallaire 《黑龙江环境通报》1995,15(8):725-729
We report the first molecular prenatal diagnosis of 3-hydroxy-3-methylglutaryl CoA lyase (HL) deficiency. The proband had a classic but severe presentation with hypoketotic hypoglycaemia and acidosis, secondary mental retardation, and epilepsy, and HL deficiency was documented in cultured fibroblasts. We found him to be homozygous for the frameshift mutation N46fs (+1), which yields a distinct pattern on single-strand conformation polymorphism (SSCP) analysis. In two subsequent pregnancies, molecular prenatal diagnosis was performed using SSCP. In the first, chorionic villus biopsy was normal. In the second pregnancy, amniocentesis revealed an affected fetus. In both pregnancies, the diagnosis was confirmed enzymatically. HL activity was less than 7 per cent of control values in amniocytes and fetal liver of the affected pregnancy. In the second pregnancy, amniotic fluid metabolite measurements by stable isotope dilution-selected ion monitoring mass spectrometry showed greater than 100-fold increases of 3-hydroxy-3-methylglutaric acid and of 3-methylglutaconic acid levels compared with controls. 相似文献