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41.
OBJECTIVE: To assess the validity of the adapted Radimer/Cornell questionnaire to measure food insecurity in low-income urban households in Tehran, the capital of Iran. DESIGN: The Radimer/Cornell questionnaire was modified and used to assess the applicability, validity and reliability of such a measure in a culturally different context of urban households in Tehran. Factor analysis and Cronbach's alpha were used to assess validity and reliability, respectively. Socio-economic characteristics and food consumption frequency of the household were used to assess the criterion validity of the questionnaire. SETTING: District 20 of Tehran. SUBJECTS: A sample of 250 Iranian nuclear households with at least one child aged 1-18 years and a non-pregnant, non-lactating woman of reproductive age, selected through a multistage random sampling method. RESULTS: Three scales, labelled as household, individual and child hunger, were extracted through factor analysis using varimax rotation. Internal consistency of the scales was 0.897, 0.820 and 0.796, respectively. Individual insecurity and child hunger were inversely correlated with monthly per capita income, father's education, mother's education and father's occupational status, and positively correlated with household size, as expected. However, household insecurity did not follow the same pattern. Consumption frequency of fruits, vegetables, dairy, red meat and rice declined as food insecurity status worsened, while bread and potato consumption increased. CONCLUSION: The results show that a modified version of the Radimer/Cornell questionnaire is a valid and reliable instrument to measure household food insecurity in a culturally different context. However, further modifications seem necessary to measure food insecurity at household level. Results lend support to the utility and applicability of experience-based measures in varying cultural communities.  相似文献   
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In this investigation, the effects of synthesized 4-chloro-2,6-bis-(2-hydroxyl-benzyl)-phenol (CBHBP) on cutaneous wound healing and growth of some of the wound contaminating microorganisms were studied. The antibacterial effects of this compound were then evaluated on Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli) and Klebsiella spp., using solid dilution method. It was demonstrated that CBHBP has a significant antimicrobial activity against S. aureus but it is not effective in the case of other microorganisms studied in this experiment. The effect of local administration of CBHBP on healing of a standard full-thickness 2 cm skin incision of skeletally mature rats was evaluated. Histological changes together with mechanical properties and dry weight content of the healing tissues at the site of the lesions were assessed in treated and untreated animals. It was observed that the injured area of the treated animals was more organized and showed more fibroblasts and less inflammatory cells. Much better maturation criteria in treated tissues were observed in comparison with those of the untreated ones which contained numerous polymorphonuclear inflammatory cells after 14 days post-injury. Many infiltrated macrophages and lymphocytes were present even 28 days after injury induction in the haphazardly organized dermis and also in subcutaneous tissues of the untreated animals. The percentage dry weight content of the treated lesions at 14 days post-injury was remarkably higher than those of the untreated animals. The results of biomechanical tensile testing showed that the ultimate tensile strength and stress of the injured skin of the treated animals were higher than those of the untreated ones. From these results, it could be concluded that CBHBP can be effective on wound healing and may be considered as a treatment regimen after evaluating its mechanism of action as well as testing its contraindications.  相似文献   
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The promotion of Blue Growth in aquaculture requires an understanding of the economic drivers influencing the sector at farm level, but the collection of reliable and comparable data at this level is time‐consuming and expensive. This study suggests an alternative strategy for qualitative sampling of freshwater trout farms in Germany, Denmark and Turkey, using a combination of existing data, group discussions and interviews with trout farmers, consultants and researchers. Nine ‘typical’ trout farming models are described, focusing on profitability, productivity and energy efficiency and allowing in‐depth comparative economic analyses of different production systems at farm level, across regions. Our results show that the majority of the farms investigated have been profitable. Turkish farms benefit from competitive advantages due to low wages, low capital investment and favourable climate conditions. Large German farms profit from local market prices and advanced farm management. Danish farms using recirculating techniques remain competitive thanks to enhanced productivity and economy of scale. However, small traditional farms in Germany and Denmark may struggle to stay competitive in the long term. Organic farms in both countries face challenges of high feed costs and comparatively low productivity with mixed success. Using edible protein energy return on investment (epEROI) as an indicator of ecological sustainability, all surveyed farms compared very favourably with the terrestrial systems of animal meat production were investigated so far.  相似文献   
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This study was performed to determine the dietary methionine requirements and its effects on growth performance, plasma and hepatic metabolites for juvenile silver catfish. The fish (initial weight = 3.26 ± 0.3 g) were distributed in 24 experimental units (35 fish each). Six diets were formulated with increasing levels of methionine (09, 16, 23, 30, 37 and 44 g/kg protein diet). Each diet was distributed randomly to the groups, with four replicates fed twice daily to apparent satiation for 15 weeks. Methionine levels influenced in body composition (moisture and ash), and submit effect on liver metabolism and plasma. The relative weight gain (RWG) and specific growth rate (SGR) increased with highest levels of methionine to 30 g/kg protein in the diet, thereafter maintaining a nearly constant level of 1.9 g/kg cystine in the protein diet. The protein retention coefficient (PRC) also increased with increasing levels of up to 23 g/kg protein diet, thereafter maintaining a constant level of 1.9 g/kg cystine protein diet until beginning to decrease at a level of 44 g/kg protein diet. In conclusion, methionine is an essential amino acid for the growth of juvenile silver catfish and exhibits an efficient capacity when provided as a synthetic amino acid. Based on the RWG and SGR data, the methionine requirement of juvenile silver catfish was estimated at 34.42 and 35.85 g/kg of the CP or 12.74 g/kg and 13.26 g/kg of the diet respectively.  相似文献   
45.
The prediction of the distribution of quantitative variables in a forest stand is of great interest to forest managers, for the evaluation of forest resources and scheduling of future silvicultural treatments. The aim of this research was to model the distribution of quantitative variables for Quercus persica in open forests in Iran. To investigate the probability distribution of trees in natural stands, 642 trees were selected for measurement using a systematic random sampling method. Selected trees were measured and data were analyzed. Gamma, beta, normal,lognormal, exponential and Weibull probability distributions were fitted to the height distribution of trees. Variables of distribution functions were estimated using the maximum likelihood estimation method. Actual probability and probability which derived from functions was compared using Kolmogorov–Smirnov and Anderson–Darling tests. Beta, Weibull and Weibull probability distributions explained the distributions of tree height, DBH and crown area.  相似文献   
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Septic tenosynovitis was diagnosed in seven cattle on the basis of history, physical examination, radiographs, cytological examination of tendon sheath fluids, and microbial culture. A commercially available indwelling multifenestrated silicone rubber drain was used to perform frequent lavage of the flexor tendon sheaths. The sepsis resolved in all cattle. Five of six cattle for which long-term (> 1 year) follow-up information was available were clinically sound on the affected limb and had remained productive members of the herd.  相似文献   
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Gesunde Pflanzen - A factorial split-plot experiment (2015–17) was carried out in a randomized complete block design with three replications at Karaj, Iran, to investigate...  相似文献   
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