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991.
Citizen science has been gaining momentum in the United States and Europe, where citizens are literate and often interested in science. However, in developing countries, which have a dire need for environmental data, such programs are slow to emerge, despite the large and untapped human resources in close proximity to areas of high biodiversity and poorly known floras and faunas. Thus, we propose that the parataxonomist and paraecologist approach, which originates from citizen‐based science, is well suited to rural areas in developing countries. Being a paraecologist or a parataxonomist is a vocation and entails full‐time employment underpinned by extensive training, whereas citizen science involves the temporary engagement of volunteers. Both approaches have their merits depending on the context and objectives of the research. We examined 4 ongoing paraecologist or parataxonomist programs in Costa Rica, India, Papua New Guinea, and southern Africa and compared their origins, long‐term objectives, implementation strategies, activities, key challenges, achievements, and implications for resident communities. The programs supported ongoing research on biodiversity assessment, monitoring, and management, and participants engaged in non‐academic capacity development in these fields. The programs in Southern Africa related to specific projects, whereas the programs in Costa Rica, India, and Papua New Guinea were designed for the long term, provided sufficient funding was available. The main focus of the paraecologists’ and parataxonomists’ activities ranged from collection and processing of specimens (Costa Rica and Papua New Guinea) or of socioeconomic and natural science data (India and Southern Africa) to communication between scientists and residents (India and Southern Africa). As members of both the local land user and research communities, paraecologists and parataxonomists can greatly improve the flow of biodiversity information to all users, from local stakeholders to international academia.  相似文献   
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Scientific literacy can be considered as a new demand of post-industrial society. It seems necessary in order to foster education for sustainability throughout students' academic careers. Universities striving to teach sustainability are being challenged to integrate a holistic perspective into a traditional undergraduate curriculum, which aims at specialization. This new integrative, inter- and transdisciplinary epistemological approach is necessary to cultivate autonomous citizenship, i.e., that each citizen be prepared to understand and participate in discussions about the complex contemporary issues posed by post-industrial society. This paper presents an epistemological framework to show the role of scientific literacy in fostering education for sustainability. We present a set of 26 collaborative concept maps (CCmaps) in order to illustrate an instance of theory becoming practice. During a required course for first-year undergraduate students (ACH 0011, Natural Sciences), climate change was presented and discussed in broad perspective by using CCmaps. We present students' CCmaps to show how they use concepts from quantitative and literacy disciplines to deal with the challenges posed by the need of achieving a sustainable development.  相似文献   
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High genetic diversity is important for the functioning of large insect societies. Across the social Hymenoptera (ants, bees, and wasps), species with the largest colonies tend to have a high colony-level genetic diversity resulting from multiple queens (polygyny) or queens that mate with multiple males (polyandry). Here we studied the genetic structure of Trigona spinipes, a stingless bee species with colonies an order of magnitude larger than those of polyandrous honeybees. Genotypes of adult workers and pupae from 43 nests distributed across three Brazilian biomes showed that T. spinipes colonies are usually headed by one singly mated queen. Apart from revealing a notable exception from the general incidence of high genetic diversity in large insect societies, our results reinforce previous findings suggesting the absence of polyandry in stingless bees and provide evidence against the sperm limitation hypothesis for the evolution of polyandry. Stingless bee species with large colonies, such as T. spinipes, thus seem promising study models to unravel alternative mechanisms to increase genetic diversity within colonies or understand the adaptive value of low genetic diversity in large insect societies.  相似文献   
999.
Temporal variation in the fatty acid (FA) composition of stomach contents of Iberian sardines was compared to the relative contribution to dietary carbon made by different prey types for fish from two areas off Portugal. The effect of the FA content of the diet on sardine muscle FA composition was also studied, aiming at (1) analysing if FA biomarkers can be used as a complementary technique for the study of sardine diet and (2) to relate spatial and temporal variations of prey FA content with sardine condition and reproduction. Significant spatial differences in the FA composition of sardine diet occurred with concentrations of n-3 polyunsaturated FA, namely eicosapentaenoic acid [EPA, 20:5n-3] and linolenic acid 18:3n-3, being significantly higher in the diet of sardines from the west coast, whilst the diet of sardines from the south coast was richer in monounsaturated fatty acids (MUFA), namely the carnivory biomarker oleic acid 18:1n-9. These results are in agreement with the higher contribution made by diatoms and dinoflagellates to the diet of sardines off the west coast. Spatial variation in sardine dietary FA was also detected in their muscle composition, specifically for EPA, and the eicosapentaenoic/docosahexaenoic acid and (n-3)/(n-6) ratios, which were higher in sardines from the west coast. No difference in FA composition was detected between sexes, and the seasonal variability in sardine total FA concentration was primarily related to the seasonality of spawning. Sardines accumulate high concentrations of FAs during the resting stage of reproduction when the feeding intensity is similar or lower to that observed during the spawning season. Additionally, sardines show a high selective retention of MUFA and polyunsaturated FA (PUFA) throughout the year except at the beginning of the spawning season, when these FAs are largely invested in the formation of the gonads. Therefore, temporal and regional differences of prey environments are strong enough to be reflected in fish body composition, namely on the accumulation of essential FAs, which can have a strong impact on reproduction success for this species.  相似文献   
1000.
Several medicinal plants used in Italy were analysed to determine natural and artificial radioactivity in those parts (leaves, fruits, seeds, roots, peduncles, flowers, barks, berries, thallus) used generally as remedies. The radionuclides were determined by alpha (238U, 210Po) and gamma (214Pb-Bi, 210Pb, 40K and 137Cs) spectrometry. 238U ranged between <0.1 and 7.32 Bq kgdry−1; 210Po between <0.1 and 30.3 Bq kgdry−1; 214Pb-214Bi between <0.3 and 16.6 Bq kgdry−1; 210Pb between <3 and 58.3 Bq kgdry−1; 40K between 66.2 and 3582.0 Bq kgdry−1; 137Cs between <0.3 and 10.7 Bq kgdry−1. The percentage of 210Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of 210Po extraction resulted 20.7 ± 7.5.  相似文献   
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