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1.
OBJECTIVES: To investigate differences in reported physical activity levels and in perceived environmental and psychosocial correlates of activity between Portuguese and Belgian adults; and to analyse the relative contribution of environmental and psychosocial variables in explaining physical activity within different contexts in Portugal and Belgium. DESIGN: Cross-sectional study. SETTING: One city in Portugal (Oeiras) and one in Belgium (Ghent). SUBJECTS: In total 526 participants, 247 from Portugal and 279 from Belgium, completed the long International Physical Activity Questionnaire and a validated questionnaire on environmental and psychosocial correlates. RESULTS: For the sum of all activities of at least moderate intensity, a significantly higher mean level of activity was found in Belgian adults (P < 0.001). However, comparable percentages of the Belgian (38%) and Portuguese (42%) samples did not meet the recommendation of 30 min per day. The variance explained by environmental factors was lower (1% to 8%) than by psychosocial factors (maximum 42%). Regression analyses showed activity-specific relations with environmental variables which were analogous in both countries. Walking/cycling for transportation and walking for recreation were related to social support from family and/or friends and to walkability and walking facilities in the neighbourhood. Recreational physical activity was mainly determined by social support, self-efficacy, and perceived benefits and barriers. CONCLUSIONS: Activity campaigns addressing psychosocial determinants are needed to encourage leisure-time activity, while a combination of neighbourhood design changes and encouragement of social support in walking is warranted to increase walking in different contexts.  相似文献   

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OBJECTIVES: To evaluate gender differences for levels of physical activity, for sedentary behaviour and for psychosocial correlates in children, to evaluate whether psychosocial correlates cluster in meaningful ways and to examine whether physical activity and sedentary behaviour differ between children of clusters, differentiated by the level of perceived barriers and benefits, attitudes, social support and self-efficacy. DESIGN: Cross-sectional study using the Flemish Physical Activity Questionnaire. SETTING: Questionnaires to be filled out by the children and one of their parents, contacted through the school system. SUBJECTS: A sample of 1124 10- to 11-year-olds (579 boys and 545 girls). RESULTS: Girls were found to be less active than boys, with boys scoring better for social support, perceived benefits and self-efficacy compared with girls. The way of clustering differed between boys and girls. Boys were allocated to three clusters: one cluster with positive correlates towards physical activity, labelled 'positives'; one with negative correlates, labelled 'negatives'; and one characterised mainly by high perceived barriers, labelled 'hindered'. In both genders the highest levels of physical activity were found in the 'positives', the lowest in the 'negatives'. In girls a fourth cluster was identified, characterised mainly by low perceived barriers and low social support. Physical activity levels in the girls of this cluster, labelled 'indifferents', were the second highest. CONCLUSIONS: More research is needed to further characterise these clusters. To prevent the physical activity decline during the transition from childhood to adulthood, novel interventions need to be explored that focus on children of the clusters with the most negative correlates.  相似文献   

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BACKGROUND: Although many school-based diet and physical activity interventions have been designed and evaluated, relatively few have been tested for the after-school setting. After-school day-care programmes at either elementary schools or private locations provide a ready-made opportunity for health programmes that may be difficult to incorporate into an already-full school day. The purpose of this paper is to report on a pilot study of an after-school adaptation of the CATCH (Coordinated Approach To Child Health) elementary school programme called the CATCH Kids Club (CKC). METHODS: The CKC was pilot-tested and formatively evaluated in 16 Texas after-school programmes: eight in El Paso and eight in Austin (four intervention and four reference sites each). Evaluation consisted of direct observation of moderate to vigorous physical activity during play time, self-reported food intake and physical activity, and focus group interviews with after-school programme staff. RESULTS: Students responded well to the physical activity and snack components and were less interested in the five-module education component. Routine staff training was a key variable in achieving proper implementation; the ideal would be a full day with repeated follow-up model teaching visits. Staff turnover was a logistic issue, as was programme leader readiness and interest in conducting the programme. Strong and significant effects were observed for the physical activity but not for the education component. The results of the physical education component suggest it is feasible, effective and ready for larger-scale evaluation or dissemination.  相似文献   

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Soil acidity can affect arbuscular mucorrhizal fungi (AMF) in many aspects. In this study, by inoculating white clover (Trifolium ripens L.) with AMF at two pH levels (pH 5.0 and 6.0), we investigated the influences of low pH on the colonization, alkaline phosphatase (ALP) activity and promoting effect of AMF, and also compared the different responses of native AMF community and exotic species (Gigaspora margarita) to low pH. PCR-DGGE profiles revealed the obvious difference in native AMF community structure between low and high pH. Compared to low pH, high pH decreased the total and vesicle colonization, external hyphae length density of native AMF, but exerted no effect on those of exotic AMF. For both native and exotic AMF, high pH enhanced the proportions of arbuscule and fungal structure with ALP activity in colonized roots. Both native and exotic AMF promoted the shoot biomass, with greater increase at low pH than at high pH. Plant growth was more dependent on exotic AMF than on native AMF at both pH levels. The same trends were observed in P uptake as in biomass. Our study suggested that the increase in pH can exert inhibitory effects on AMF species native to acidic soil, including ecological (community structure), functional (ALP activity) and developmental (hyphal length, vesicle and arbuscule percentage, total colonization) aspects, but have no effect on exotic species in the present experiment.  相似文献   

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Project Energize is a through-school nutrition and activity programme that is being evaluated in a 2-year, cluster-randomised, longitudinal study. The present paper describes the background of the programme and study, the programme development and delivery, the study methodology including randomisation, measurement and analysis tools and techniques, and the mix of the study population. The programme is being delivered to sixty-two primary schools with sixty-two control schools, each limb containing about 11 000 students. The children in the evaluation cohort are 5 or 10 years old at enrolment; the randomisation protocol has achieved post-consent enrolment of 3000 evaluation participants, who are comparable by age, sex and school decile. End-point measures include body composition and associated physical characteristics, fitness, home and school environment and practice.  相似文献   

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Beneficial soil bacteria are able to colonize plant root systems promoting plant growth and increasing crop yield and nutrient uptake through a variety of mechanisms. These bacteria can be an alternative to chemical fertilizers without productivity loss. The objectives of this study were to test bacterial inoculants for their ability to promote nutrient uptake and/or plant growth of rice plants subjected to different rates of chemical fertilizer, and to determine whether inoculants could be an alternative to nitrogen fertilizers. To test the interaction between putatively beneficial bacteria and rice plants, field experiments were conducted with two isolates: AC32 (Herbaspirillum sp.) and UR51 (Rhizobium sp.), and different nitrogen fertilization conditions (0%, 50%, and 100% of urea). Satisfactory results were obtained in relation to the nutrient uptake by plants inoculated with both isolates, principally when the recommended amount of nitrogen fertilizer was 50% reduced. These bacterial strains were unable to increase plant growth and grain yield when plants were subjected to the high level of fertilization. This study indicated that the tested inoculant formulations can provide essential nutrients to plants, especially when the levels of nitrogen fertilizers are reduced.  相似文献   

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International experience of Policy Councils on food and nutrition has developed over recent decades but they have not received the attention that is due to them. The 1992 International Conference on Nutrition recommended that governments create Food Policy Councils but few have been created. There has been more experience in local and sub-national policy councils, particularly in North America. Developing country experience of attempting to improve food policy integration stems from the 1970s. The UK's House of Commons' (Parliamentary) Health Committee, in its 2004 report on obesity, reviewed current policy determinants of the rise in obesity, concluding that national food and health policy lacked coherence, integration and effectiveness. To address this vacuum, it proposed the creation of a new 'Council of Nutrition and Physical Activity to improve co-ordination and inject independent thinking into strategy'. The case for creating such a Council in the UK is reviewed, as are possible organisational options, functions and remit. A Council could be created under the forthcoming Public Health Act. The purpose of the new Council would be to provide independent advice and strategic advice as well as monitor the linkages between policies on food, nutrition and physical activity, noting their environmental implications.  相似文献   

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A. R. Dexter   《Geoderma》2004,120(3-4):201-214
A soil physical parameter, S, is defined. It is equal to the slope of the soil water retention curve at its inflection point. This curve must be plotted as the logarithm (to base e) of the water potential against the gravimetric water content (kg kg−1). The value of S is indicative of the extent to which the soil porosity is concentrated into a narrow range of pore sizes. In most soils, larger values of S are consistent with the presence of a better-defined microstructure. Much previous work has shown that this microstructure is responsible for most of the soil physical properties that are necessary for the proper functioning of soil in agriculture and the environment. The use of S is illustrated with examples of soils with different texture, density (or degree of compaction), and organic matter (OM) content. The effects of S on root growth in soil are investigated, and S is shown to be a better indicator of soil rootability than bulk density. It is suggested that S can be used as an index of soil physical quality that enables different soils and the effects of different management treatments and conditions to be compared directly.  相似文献   

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骨炭的土壤改良培肥和小萝卜增产提质效应研究   总被引:2,自引:0,他引:2       下载免费PDF全文
采用田间随机区组试验设计,研究了不施骨炭、150、300、450、600 kg·hm-2 骨炭5 个处理对土壤养分  相似文献   

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OBJECTIVE: Despite the increasing dependence on systematic reviews to summarise the literature and to issue public health recommendations, the formal assessment of the reliability of conclusions emerging from systematic reviews has received little attention. The main goal of the present study was to evaluate whether two independent centres, in two continents, draw similar conclusions regarding the association of food, nutrition and physical activity and endometrial cancer, when provided with the same general instructions and with similar resources. DESIGN: The assessment of reproducibility concentrated on four main areas: (1) paper search and selection; (2) assignment of study design; (3) inclusion of papers; and (4) individual studies selected for meta-analysis and the summary risk estimate obtained. RESULTS: In total 310 relevant papers were identified, 166 (54 %) were included by both centres. Of the remaining 144 papers, 72 (50 %) were retrieved in the searches of one centre and not the other (54 in centre A, 18 in centre B) and 72 were retrieved in both searches but regarded as relevant by only one of the centres (52 in centre A, 20 in centre B). Of papers included by both centres, 80 % were allocated the same study design. Agreement for inclusion of cohort-type and casekey' papers was 87 %. Summary risk estimates from meta-analyses were similar. CONCLUSIONS: Transparency of process and explicit detailed procedures are necessary parts of a systematic review and crucial for the reader to interpret its findings.  相似文献   

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Changes in land use can significantly affect soil properties. This study was conducted in the Taleghan watershed of Tehran Province, Iran, to determine the effects of land use changes on soil organic matter (SOM) and soil physical properties including soil aggregate stability, saturated hydraulic conductivity, infiltration rate, available water content, total porosity and bulk density (BD). In the present study, two sites contained adjacent land uses of natural pasture and dryland farming were selected. Soil samples were taken from depths of 0–15 and 15–30 cm for each land use. The results indicated that the conversion of natural pasture to dryland farming led to a significant decrease in SOM at 0–30 cm in the first and second sites (24.7 and 44.2%, respectively). In addition, a significant increase in BD was observed at a depth of 0–30 cm in dryland farm soils (1.39 g cm–3) compared to pastureland (1.20 g cm–3) at the first site. An increase in BD was also observed at the same depth of dryland farm soils (1.46 g cm–3) and pastureland soils (1.42 g cm–3) at the second site. In addition, total porosity, mean‐weight diameter of aggregates, saturated hydraulic conductivity, available water content and estimated final infiltration rate showed significant differences between land uses. The results showed that the conversion of natural pasture to dryland farming alters soil properties that negatively affect soil productivity and erodibility. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

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Li  Shan  Yang  Yuechao  Li  Yuncong  Gao  Bin  Tang  Yafu  Xie  Jiazhuo  Zhao  Hongcheng 《Journal of Soils and Sediments》2020,20(3):1454-1467
Purpose

Crops grow poorly in saline-sodic soils, and the productivity of these soils can be dramatically improved with proper amendments. Current research mainly focuses on either organic or inorganic soil amendments, whereas few studies address options of combining organic and inorganic amendments. The objective of this study was to develop new organic and inorganic soil amendments which can lower the soil pH, replace sodium, and improve soil structure.

Materials and methods

Polyhalite (PL), microporous potassium-silicon-calcium mineral fertilizer (MF), furfural residue (FR), and fulvic acid (FA) were mixed with four different ratios to produce organic and inorganic soil amendments: PLFR, PLFA, MFFR, and MFFA. And their optimum mixing ratios were determined by comparing the potassium, calcium concentrations, and pH of filtrate after dissolution. Then, a leaching experiment was conducted by packing mixtures (mass ratio of soil to amendment = 219:1, equivalent to 13 t/hm2) of the saline-sodic soil with each one of these amendments plus two contrasts, gypsum (GP), and no amendment (CK). And the remediation effect was compared by pH, EC, ESP, texture, organic recombination degree of clay, saturated hydraulic conductivity, water-stable aggregates fraction, and enzyme (urease, alkaline phosphatase, and catalase) activities of soil.

Results and discussion

After four times leaching experiment, soil treated with PLFR had lower pH and 25.86% lower exchangeable sodium than untreated soils. The water-stable small macroaggregate fractions and saturated hydraulic conductivity of the MFFR-treated soils were significantly increased by 133% and 31%, respectively. Also, the total soil and heavy fraction organic carbons of the soils treated with MFFR in addition to its alkaline phosphatase activity were all significantly higher than the other treatments.

Conclusions

The results revealed that MFFR has more potential as a soil amendment to improve soil structure and quality and thus help in the development and use of saline-sodic lands for agriculture.

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OBJECTIVE: To describe the relationship between dietary intake and different levels and types of physical activity (PA). DESIGN: Cross-sectional evaluation of the EPIPorto study. Energy expenditure (metabolic energy equivalent tasks) and dietary intake during the past year were assessed using a PA questionnaire and a semi-quantitative food-frequency questionnaire, respectively. SETTING: Representative sample of adults in Porto, Portugal. SUBJECTS: Data were analysed for 2404 Portuguese Caucasian adults, aged between 18 and 92 years. RESULTS: For total PA, males who were active had significantly higher mean intake of energy (10.76 (2570.7) vs. 9.78 (2336.9) MJ/d (kcal/d), P < 0.001) and lower level of protein consumption (16.9 vs. 17.6 % of energy, P < 0.001) compared with sedentary males. In males, the association between total PA and energy intake remained after adjustment for age, education and body mass index. Similar results were observed when occupational activity was analysed. Concerning the energy expended in leisure time, in both genders, after adjustment for the previously described variables, a significant positive association was found between PA and intake of vitamin C (g/d): beta = 0.12, 99 % confidence interval (CI) 0.02, 0.21 for females and beta = 0.13, 99 % CI 0.03, 0.22 for males. Leisure-time activity in females was also positively associated with intakes of fibre, vitamin E, folate, calcium and magnesium, and negatively associated with saturated fat. CONCLUSIONS: Higher levels of PA in leisure time were associated with higher intakes of micronutrients and lower intakes of saturated fat, particularly in females. For total and occupational PA, similar nutrient intake was observed between active and sedentary individuals.  相似文献   

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Qi  Le  Zhou  Peng  Yang  Laishu  Gao  Ming 《Journal of Soils and Sediments》2020,20(2):973-981
Journal of Soils and Sediments - Land reclamation, as a measure of increasing cultivated land area, is being popularized in China in the past decades. However, the impact of land reclamation on...  相似文献   

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