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OBJECTIVE: The aim of the study was to investigate the relative importance of personal and social environmental predictors of the consumption of fruit, high-fat snacks and breakfast. DESIGN: A school-based cross-sectional survey. Data were collected through written questionnaires. SETTING: Students from eight schools in the southern part of The Netherlands. SUBJECTS: Six hundred and one students from preparatory secondary vocational education schools. RESULTS: About a quarter of the variation in actual behaviours and intentions to change the behaviours could be explained. Stepwise multiple regression analysis revealed that, for all three behaviours, higher intention to change was especially associated with a more positive attitude and subjective norm, and higher intentions to increase fruit intake with more positive self-efficacy expectations. With regard to actual consumption, a more positive attitude towards eating fruit was the only significant correlate of a higher consumption of fruit. A more positive attitude towards eating high-fat snacks, perceived lower intake of the mother, and higher food availability and accessibility were associated with consumption of high-fat snacks, and a more positive attitude to breakfast more frequently was associated with more frequent breakfast consumption. CONCLUSION: The results indicate that adolescents' attitudes are the most important determinants of different health-related eating behaviours and intentions to change. Interventions promoting a healthy diet for adolescents should include creative strategies to achieve positive associations with healthy dietary changes.  相似文献   

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Marine turtles are a taxon of world-wide conservation concern. Effective long-term monitoring is hampered by the fact that populations are widely dispersed except during the breeding season. Thus most monitoring programmes focus on nesting beaches, necessitating resource intensive studies, often over months, that could conceivably, be less comprehensive and focus on more parsimonious sampling. We analyse 11 years of exhaustive monitoring data for two species of Mediterranean marine turtles (Chelonia mydas and Caretta caretta). We resample using a variety of plausible sub-sampling regimens to estimate the total annual nesting population. We project our dataset into the future applying a range of population change rates to explore how adopting a monitoring programme based on sub-sampling would, for example, affect our ability to detect population decline. We show that accurate annual population estimates can be achieved with as few as 14 days of survey effort providing monitoring spans the peak of nesting. Furthermore, the modelled impact of sampling-based monitoring suggests that the duration to detect population change is not increased greatly. Our findings have implications for all marine turtle monitoring and have applicability to other animal groups. It is often considered desirable to perform exhaustive monitoring, with aversion of basing policy recommendations on partial data. However, comprehensive long-term monitoring programmes, particularly in developing nations, although presenting a number of advantages, are often impossible. Accurate total annual censuses can be achieved through a variety of sub-sampling regimens without sacrificing the ability to detect changes in the population trends over time. In this example, a solid block of at least 3 weeks sampling that encompasses the peak of the nesting season is advised.  相似文献   

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In order to prioritise interventions for micronutrient deficiencies in China, the populations affected by iron and zinc deficiencies were assessed based on data from the 2002 China National Nutrition and Health Survey. The costs and cost-effectiveness of supplementation, food diversification and food fortification were estimated using the standard World Health Organization ingredients approach. Results indicated that 30% of children (60 years), pregnant and lactating women, and 20% of women of reproductive age were anaemic, some 245 million people. Approximately 100 million people were affected by zinc deficiency (zinc intake inadequacy and stunting), the majority living in rural areas. Among interventions on iron and zinc deficiency, biofortification showed the lowest costs per capita, I 0.01 (international dollars), while dietary diversification through health education represented the highest costs at I 1148(international dollars). The cost-effectiveness of supplementation, food fortification and dietary diversification for iron deficiency alone was I 179(international dollars) , I 66 and I 103 (international dollars) per disability-adjusted life-year (DALY), respectively. Data for biofortification were not available. For zinc deficiency, the corresponding figures were I 399(international dollars), I 153(international dollars) and I 103(international dollars) per DALY, respectively. In conclusion, iron and zinc deficiencies are of great public health concern in China. Of the two long-term intervention strategies, i.e. dietary diversification and biofortification with improved varieties, the latter is especially feasible and cost-effective for rural populations. Supplementation and fortification can be used as short-term strategies for specific groups.  相似文献   

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The connection between sulphur (S) and selenium (Se) metabolism makes rapeseed (Brassica napus) an attractive candidate for Se fortification. Unfortunately, fertilizers may interfere with the availability of selenate (SeO42-) in numerous ways, including both soil and physiological processes. Experiments on two agricultural soils amended with SeO42- (32 μg Se kg?1 soil), sulphate and phosphate (each at three levels of supply) were established to elucidate the effect of these anions on the selenization efficiency. Maximal efficiency in Chernozem soil was roughly two-fold higher (455 μg Se kg?1 seed) than in Cambisol. Sulphate significantly decreased (up to 28%) the seed Se contents in Cambisol, while an enhancement (up to 33%) was found in Chernozem. In the Chernozem, the induction of collective S and Se translocation toward the seed more than compensated for any competition effects due to the highest sulphate supply. In Cambisol, plant Se distribution did not follow that of S as closely as in Chernozem. Phosphate did not significantly alter the fortification efficiency. Resistance of rapeseed proteins to protease hampered a quantitative investigation of changes in Se speciation under different S supplies. Nevertheless, protein-bound selenomethionine was the predominant Se storage form and traces of other Se species were also identified.  相似文献   

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The main goal of this study was to propose a reliable method to verify the geographical origin of meat, establishing the influence of soil and water on its isotopic and elemental composition. Thus, beef meat, soil, and water samples were collected from three major cattle-producing regions of Argentina (Buenos Aires, Córdoba, and Entre Ríos). Multielemental composition was determined on these three matrices by inductively coupled plasma mass spectrometry (ICP-MS), δ(13)C and δ(15)N by isotope-ratio mass spectrometry (IRMS), and the (87)Sr/(86)Sr ratio by thermal ionization mass spectrometry (TIMS). Soil and drinking water samples could be characterized and clearly differentiated by combining the isotopic ratios and elements, demonstrating differences in geology and climatic conditions of three regions. Similarly, meat originating at each sampling area was characterized and differentiated using only five key variables (Rb, Ca/Sr, δ(13)C, δ(15)N, and (87)Sr/(86)Sr). Generalized procrustes analysis (GPA), using the three studied matrices (soil, water, and meat) shows consensus between them and clear differences between studied areas. Furthermore, canonical correlation analysis (CCA) demonstrates significant correlation between the chemical-isotopic profile of meat with those corresponding to both soil and water (r(2) = 0.93, p < 0.001; and r(2) = 0.83, p < 0.001, respectively). So far, there are clear coincidences between the meat fingerprint and those from soil/water where cattle grew, presenting a good method to establish beef provenance. To the authors' knowledge this is the first report linking the influence of soil and water all together on the composition of beef, presenting the basis for the authentication of Argentinean beef, which could be extended to meat from different provenances.  相似文献   

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OBJECTIVE: To assess whether a food variety score (FVS) and/or a dietary diversity score (DDS) are good indicators of nutrient adequacy of the diet of South African children. METHODS: Secondary data analyses were undertaken with nationally representative data of 1-8-year-old children (n = 2200) studied in the National Food Consumption Study in 1999. An average FVS (mean number of different food items consumed from all possible items eaten) and DDS (mean number of food groups out of nine possible groups) were calculated. A nutrient adequacy ratio (NAR) is the ratio of a subject's nutrient intake to the estimated average requirement calculated using the Food and Agriculture Organization/World Health Organization (2002) recommended nutrient intakes for children. The mean adequacy ratio (MAR) was calculated as the sum of NARs for all evaluated nutrients divided by the number of nutrients evaluated, expressed as a percentage. MAR was used as a composite indicator for micronutrient adequacy. Pearson correlation coefficients between FVS, DDS and MAR were calculated and also evaluated for sensitivity and specificity, with MAR taken as the ideal standard of adequate intake. The relationships between MAR and DDS and between anthropometric Z-scores and DDS were also evaluated. RESULTS: The children had a mean FVS of 5.5 (standard deviation (SD) 2.5) and a mean DDS of 3.6 (SD 1.4). The mean MAR (ideal = 100%) was 50%, and was lowest (45%) in the 7-8-year-old group. The items with the highest frequency of consumption were from the cereal, roots and tuber group (99.6%), followed by the 'other group' (87.6%) comprising items such as tea, sugar, jam and sweets. The dairy group was consumed by 55.8%, meat group by 54.1%, fats by 38.9%, other vegetables by 30.8%, vitamin-A-rich by 23.8%, other fruit by 22%, legumes and nuts by 19.7% and eggs by 13.3%. There was a high correlation between MAR and both FVS (r = 0.726; P < 0.0001) and DDS (r = 0.657; P < 0.0001), indicating that either FVS or DDS can be used as an indicator of the micronutrient adequacy of the diet. Furthermore, MAR, DDS and FVS showed significant correlations with height-for-age and weight-for-age Z-scores, indicating a strong relationship between dietary diversity and indicators of child growth. A DDS of 4 and an FVS of 6 were shown to be the best indicators of MAR less than 50%, since they provided the best sensitivity and specificity. CONCLUSION: Either FVS or DDS can be used as a simple and quick indicator of the micronutrient adequacy of the diet.  相似文献   

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Journal of Soils and Sediments - Charcoal production during the nineteenth century transformed landscapes in the Brazilian Atlantic Forests in Rio de Janeiro city. These paleo-territories were...  相似文献   

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In this study a specific taste modulating flavor ingredient, N-lactoylguanosine 5'-monophosphate (N-lactoyl GMP), was determined in bonito (Japanese, Katsuobushi, dried fermented skipjack) and in powdered bonito using liquid chromatography-electrospray ionization (+) mass spectrometry-mass spectrometry (LC-ESI(+)-MS/MS) with a methanol/ammonium acetate or formate gradient. Furthermore, the influence of ion suppression due to sample matrix effect was investigated and was found to substantially influence the total MS response of N-lactoyl GMP; by adjusting the LC conditions the response could be approximately 5-fold-enhanced. The N-lactoyl GMP concentrations in different types of bonito products were between 0.2 and 2.4 microg/g.  相似文献   

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There are many variables within an urban landscape that can be expected to influence faunal diversity. We used a mechanistic approach to observe the relative importance of each of these variables in describing the diversity of avian communities in urban and peri-urban areas of Cape Town, South Africa situated within Cape Floristic Region, a global plant biodiversity hotspot. We expected to find a strong influence of habitat amount and arrangement across a fragmented urban-rural gradient. Birds were sampled in patches of fragmented Cape Flats Sand Fynbos at 39 locations during the middle of summer (November-January 2008/2009). Environmental data included on-site observations, existing GIS layers, and remotely sensed data. Bird community composition was related to habitat amount, arrangement, and quality. Correlations, partial correlations and structural equation analysis showed that habitat amount and arrangement had insignificant effects on species richness across the urban gradient. Changes in urban density and the presence or absence of the invasive alien tree species Acacia saligna (blue wattle) appeared to be the main drivers of avian species richness. Increasing urban density, decreasing A. saligna density and decreasing canopy height correlated with higher avian species richness, with confounding variables corrected for. For the management of urban biodiversity, our results suggest that the most urgent focus should be on retaining the quality remaining areas of native vegetation (and particularly, containing the spread of A. salgina) rather than extending current networks with poor quality habitat. More generally, habitat quality appears to be more important than habitat amount or arrangement in this system. We suggest that this observation be encorporated into further research to more effectively predict avian responses to landscape change and that more must be done to adequately capture the critical and complex role of the matrix in terrestrial systems.  相似文献   

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Species are classified as Data Deficient on the IUCN Red List if there is inadequate information to make an assessment of their extinction risk based on distribution and/or population status. Data Deficient is probably the most controversial and misunderstood of IUCN Red List categories. All 63 globally Data Deficient bird species lack sufficient information on population size, trends, distribution and/or threats to assess them against the Red List criteria. For 10 species (16%) the paucity of data may be a consequence of taxonomic uncertainty. Three species are known only from specimens of uncertain geographic provenance. Since 1988, 58 Data Deficient birds have been recategorised, mainly as Near Threatened (48%) or Least Concern (16%). We speculate that of the remaining Data Deficient birds, just 14% may prove to be threatened. Proportionately fewer birds (0.6%) are listed as Data Deficient as compared with mammals (15%), amphibians (25%), corals (17%), conifers (4%) and cycads (6%), because birds are better known and perhaps because for birds greater use is made of contextual information (e.g. condition of habitats, likely ecology/habitat preferences and trends in known threatening processes) to assign alternative categories where this is plausible and precautionary. Ensuring consistency between taxonomic groups is essential for the credibility of the IUCN Red List. For non-avian taxa, the higher proportions of Data Deficient species introduces greater uncertainty in estimates of overall extinction risk, but the results from birds hint that the real values may fall at the lower end of these estimates. Data Deficient species should be treated precautionarily in terms of protection and assessing environmental impacts, and regarded as urgent priorities for surveys and research to elucidate their true status. Greater attention should also be given to documenting data quality and uncertainty for Red List assessments of threatened and non-threatened species.  相似文献   

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