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101.
ABSTRACT

This paper interprets aspects of the implementation of environmental education in a Higher Education Institution, situated in a developing country, to promote Education for Sustainable Development (ESD). The paper will allow educators to categorise the multiplicity of ESD programmes and projects in higher education institutions, determine their limitations and acceptability, and benefit from the theoretical framework of affective learning in designing new ESD interventions. The paper will also provide an overview of the processes required to establish ESD in developing and developed countries. This paper will further help universities to develop a better understanding of how integration of the three components of sustainable development – economic development, social development and environmental protection – can be incorporated in higher education. The paper explores the challenges for planning the implementation of ESD in an education faculty, outlining the potential lessons learned that could assist in improving ESD efforts in Faculties of Education.  相似文献   
102.
beta-Hexachlorocyclohexane-14C (1.5 ppm) was administered in the diet to rats for one week. During the elimination phase three therapeutic agents were fed to enhance the clearance. Renal and fecal excreted radioactive products were collected for 8 weeks and extracted. Although significant differences in the total excreted amount of radioactivity were registered between controls and treated rats, there were no quantitative differences in the extractability of the excreta and no differences in the chemical nature of metabolites found. Radioactivity in urine consisted to 100% of conversion products, about 30% of which were unextractable residues. In the organic soluble fraction the 2,4,6-trichlorophenol was the major metabolite in urine and the only metabolite detected in feces. Minor conversion products of beta-HCH in urine were a trichlorohydroxyme-thoxybenzene, a dichlorophenol and a trace of a tetrachlorocyclohexane-isomer.  相似文献   
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Two species of giant clams, Tridacna maxima and T. squamosa, coexist in the Red Sea, but exhibit distinctly different depth distributions: T. maxima mostly occurs in shallow waters (reef flat and edge), while T. squamosa may occur down to the lower fore-reef slope. Giant clams have been described as mixotrophic, capable of both filter-feeding and photosynthesis due to algal symbionts (zooxanthellae), therefore, observed depth preferences were investigated in relation to possible differences in autotrophy vs. heterotrophy. This study was conducted from April to June 2004, at the reef near the Marine Science Station, Aqaba, Gulf of Aqaba, Red Sea, and in May 2007, at a reef near Dahab, Sinai Peninsula, Egypt. In situ measurements using a submersible pulse amplitude modulated fluorometer (Diving PAM), revealed no significant differences in effective PSII quantum yield (ΔF/Fm′) and relative electron transport rates (ETR) between the two species; but rapid light curves (ETR vs. light, photosynthetically active irradiance, PAR) showed significant differences in maximum photosynthetic rates (ETRmax), with 20% higher values in T. maxima. Chamber incubations displayed higher net and gross oxygen production by T. maxima (88.0 and 120.3 μmol O2 cm−2 mantle area day−1) than T. squamosa (56.7 and 84.8 μmol O2 cm−2 mantle area day−1); even under shading conditions (simulated depth of 20 m) T. maxima still achieved 93% of the surface gross O2 production, whereas T. squamosa reached only 44%. A correlation was found between ETR and net photosynthesis measured as oxygen production (T. maxima: R 2 = 0.53; T. squamosa: R 2 = 0.61). Calculated compensation depth (CD) (gross photosynthesis equals respiration) in T. maxima (16 m) matches the maximum depth of occurrence in this study (17 m). By contrast, the CD of T. squamosa (9 m) was much shallower than the maximum vertical range (42 m). Findings suggest T. maxima is a strict functional photoautotroph limited by light, whereas T. squamosa is a mixotroph whose photoautotrophic range is extended by heterotrophy. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
107.
Despite the rapid growth of organizational research on subjective time, the extant literature is fragmented due to a lack of conceptual clarification and integration of temporal constructs. To address this fragmentation, we synthesize temporal research from both organizational behavior and adjacent disciplines (i.e., strategy, entrepreneurship, and organizational theory) and introduce a framework that allocates temporal constructs according to their basic conceptual nature (trait–state) and level of analysis (individual–collective). We employed the Linguistic Inquiry and Word Count text analysis to determine the trait–state property of the constructs and a coding method to determine their level of analysis. This framework categorizes four generic types of subjective time: individual temporal disposition, individual temporal state, collective temporal state, and collective temporal disposition. We clarify the conceptualizations of the temporal constructs belonging to each of the four archetypes of subjective time and review their key findings in the organizational literature. Based on this integrative framework, we identify critical knowledge gaps in the current state of research and chart a future agenda with specific suggestions.  相似文献   
108.
A procedure for the estimation of hydrocarbon emissions caused by deciduous forests, coniferous forests, mixed forests, agricultural areas and grassland is described. Here, the hydrocarbons are divided into three groups: isoprene, monoterpenes and other biogenic-emitted, volatile organic compounds. The emissions are calculated for a summer day in the eastern part of Germany using a land use data base. The spatial distribution of the emissions is represented as well as the variation of the emissions in the course of the summer day. The estimation of the emissions reveals that the daily amount of biogenic hydrocarbon emissions during the summer can have the same magnitude as the anthropogenic hydrocarbon emissions.  相似文献   
109.
Scientific findings from the last decades have clearly highlighted the need for a more comprehensive approach to atmospheric change processes. In fact, observation of atmospheric composition variables has been an important activity of atmospheric research that has developed instrumental tools (advanced analytical techniques) and platforms (instrumented passenger aircrafts, ground-based in situ and remote sensing stations, earth observation satellite instruments) providing essential information on the composition of the atmosphere. The variability of the atmospheric system and the extreme complexity of the atmospheric cycles for short-lived gaseous and aerosol species have led to the development of complex models to interpret observations, test our theoretical understanding of atmospheric chemistry and predict future atmospheric composition. The validation of numerical models requires accurate information concerning the variability of atmospheric composition for targeted species via comparison with observations and measurements.In this paper, we provide an overview of recent advances in instrumentation and methodologies for measuring atmospheric composition changes from space, aircraft and the surface as well as recent improvements in laboratory techniques that permitted scientific advance in the field of atmospheric chemistry. Emphasis is given to the most promising and innovative technologies that will become operational in the near future to improve knowledge of atmospheric composition. Our current observation capacity, however, is not satisfactory to understand and predict future atmospheric composition changes, in relation to predicted climate warming. Based on the limitation of the current European observing system, we address the major gaps in a second part of the paper to explain why further developments in current observation strategies are still needed to strengthen and optimise an observing system not only capable of responding to the requirements of atmospheric services but also to newly open scientific questions.  相似文献   
110.
The objective of this work was to test the compliance of commercially available batteries with the German Battery Ordinance, a project of the German government that was initiated by the Federal Environment Agency. Different types of commercially available dry cells were analysed for their cadmium, lead and mercury contents. The dry cells underwent mechanical pre-treatment, separation of the different components and microwave-assisted digestion before determination of the heavy metals. Mercury is sometimes added to prevent the generation of gaseous hydrogen from the electrochemical process. Lead could be present since it is sometimes used as an alloying element of zinc. Cadmium has no technical importance and is an undesirable impurity. None of the batteries contained higher heavy metal mass fractions than the permissible limits.  相似文献   
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