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1.
Households in rural Kenya are sensitive to weather shocks through their reliance on rain-fed agriculture and livestock. Yet the extent of vulnerability is poorly understood, particularly in reference to extreme weather. This paper uses temporally and spatially disaggregated weather data and three waves of household panel survey data to understand the impact of weather extremes –including periods of high and low rainfall, heat, and wind– on household welfare. Particular attention is paid to heterogeneous effects across agro-ecological regions. We find that all types of extreme weather affect household well-being, although effects sometimes differ for income and calorie estimates. Periods of drought are the most consistently negative weather shock across various regions. An examination of the channels through which weather affects welfare reveals that drought conditions reduce income from both on- and off-farm sources, though households compensate for diminished on-farm production with food purchases. The paper further explores the household and community characteristics that mitigate the adverse effects of drought. In particular, access to credit and a more diverse income base seem to render a household more resilient.  相似文献   

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A research of estimating the prevalence og vitamin A deficiency in Tajik children was made. At revealed that 51.8% of children of age 6-59 months suffer from vitamin A defficiency. 97.4% of the examined pregnant women have no information at all about vitamin A and didnit take any vitamins including vitamin A.  相似文献   

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HPLC法同时测定保健食品中维生素A和维生素E   总被引:1,自引:0,他引:1  
建立了高效液相色谱法(HPLC)同时测定保健食品中VA、VE的方法。样品预处理采用经二甲亚砜和正己烷的混合溶液于60℃剧烈振摇提取30min,离心后吸取正己烷层,合并3次提取的溶液后直接进行液相色谱测定。方法采用Inertsil氨基柱(4.6 mm×250 mm,5μm),以含0.1%异丙醇的正己烷为流动相进行等度洗脱,流速为1.0 m L/min,检测波长为280nm,柱温为25℃。结果表明,VA、VE分别在5~25μg/m L、100~500μg/m L范围内线性关系良好,相关系数分别达0.9997和0.9998,保留时间和峰面积的日内和日间精密度均较好,平均加标回收率在97.53%~100.67%之间,相对标准偏差(RSD)均小于2.0%。与相应的检验标准测定结果比较,相对偏差均小于1.0%,无明显差异。该方法快速、准确、可靠,适用于不同厂家、不同配方的保健食品中添加合成VA、VE的同时定量测定。  相似文献   

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随着经济的发展、人们生活水平的提高,食用油消费也发生着深刻的变化。以实证数据为基础,分析出当前我国农村居民食用油消费量远远超出膳食指南推荐摄入量,食用油的消费品种相对单一,且消费品种与当地的油料作物生产结构相一致。在消费偏好方面,主要受口味、安全与习惯影响。不合理的食用油消费不仅深刻影响着消费者的健康状况,也具有外部性,给社会造成沉重的负担。根据我国农村居民食用油消费中存在的问题,针对性地提出引导农村居民合理选择和消费食用油的策略。  相似文献   

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In 1997, the reduction of child mortality became a policy priority for the Government of Niger because Niger's child mortality rate was the highest in the world. The Ministry of Public Health, Helen Keller International (HKI), and UNICEF spearheaded a coalition-building process linking vitamin A deficiency (VAD) control to national child survival goals. An evidence-based advocacy strategy was developed around the child survival benefits of adequate and sustained VAD control with one unambiguous message: "VAD control can avert over 25,000 child deaths per year." As a result, in 1997 Niger became one of the first countries in Africa to effectively integrate vitamin A supplementation into National Immunization Days (NIDs) for polio eradication. The challenge was then to provide children with a second annual dose of vitamin A. This led in 1999 to the first ever National Micronutrient Days (NMDs) in Africa. NMDs are mobilization campaigns in which caregivers are actively encouraged to take their children for the delivery of vitamin A supplements. Since 1999, the combination of NIDs and NMDs has ensured that over 80% of children 6 to 59 months of age receive two vitamin A doses annually. The success of NIDs/NMDs has relied on five pillars: leadership and ownership by the Ministry of Public Health; district-level planning and implementation; effective training and flexible delivery mechanisms; effective social information, communication, and mobilization; and responsiveness and flexibility of Ministry of Public Health and development partners. This successful approach has been widely disseminated, notably through the West African Nutrition Focal Points Network.  相似文献   

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建立正相高效液相色谱法测定乳制品中维生素A质量浓度的方法。采用Agilent ZORBAX Rx-SIL色谱柱,以95%正己烷-5%异丙醇为流动相,流速为1.0 mL/min,PDA检测波长325 nm。结果表明:维生素A质量浓度在0.3~100 mg/L范围内,峰面积与质量浓度具有良好的线性关系;方法的精密度良好,平均相对标准偏差为1.2%,平均加标回收率为91.8%。结论:与GB 5413.9-2010中的反相高效液相色谱法相比,样品前处理操作简单、分离效果好、保留时间缩短。可作为乳制品中维生素A质量浓度的一种快速检测方法。  相似文献   

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A food consumption survey on 420 children was conducted in four areas in Benin to identify the local vitamin A (VA)-rich foods most frequently eaten and assess their contribution to the coverage of VA requirements of young children. Mangoes, eggs, red palm oil, various leafy vegetable (LV) sauces and palm nut juice sauce appeared to be the main VA-rich foods consumed. The recipes of the most promising sauces were characterised. Sauces with red palm oil/palm nut juice showed high carotenoid contents ranging from 0.9 ± 0.3 to 4.0 ± 0.8 mg Retinol Activity Equivalent/100 g dry matter (DM). Lipid contents were also high (from 39.6 to 66.8 g/100 g DM). When consumed, and taking into account the mean quantity eaten per meal, LV sauces containing red palm oil or palm nut juice contributed to the meeting of more than 70% of the recommended VA intake of young children.  相似文献   

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目的分析高效液相色谱法测定维生素片中维生素A醋酸酯含量的不确定度来源和影响不确定度的因素,为简化评定方法和提高检测质量提供依据。方法根据检测过程,建立数学模型,分析影响不确定度因素的来源,通过对不确定度进行量化分析,得出扩展不确定度。结果由各不确定度分量评定结果可以看出,高效液相色谱法测定维生素片中维生素A醋酸酯含量的扩展不确定度为0.46 mg/100 g,平均含量为35.72mg/100 g,包含因子k=2。结论高效液相色谱法测定维生素片中维生素A醋酸酯含量的不确定度主要由标准溶液配制、重复测定和稀释标准溶液引入。因此在含量检测过程中,要控制各不确定因素,以提高检测准确性。  相似文献   

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以石油醚为溶剂,用索氏提取法提取了黑芝麻、白花生、黑花生、葵花籽、大豆、棉花籽的油脂。油样品先用正己烷溶解,然后用甲醇定容,其中正己烷含量为20%(v/v),用Hypersil ODS2 5μm色谱柱,甲醇为流动相,对所提油脂中维生素A、α-维生素E、γ-(β)维生素E、δ-维生素E含量进行检测。实验结果表明,在204nm波长下,维生素A、α-维生素E、γ-(β)维生素E、δ-维生素E在0200μg/m L范围内与峰面积有良好的线性关系,标准曲线相关系数r均大于0.9978。维生素A、α-维生素E、γ-(β)维生素E、δ-维生素E加标平均回收率分别为97.83%、98.58%、98.75%、99.93%。   相似文献   

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HPLC法同时测定植物油中维生素A和不同构型维生素E含量   总被引:2,自引:0,他引:2  
以石油醚为溶剂,用索氏提取法提取了黑芝麻、白花生、黑花生、葵花籽、大豆、棉花籽的油脂。油样品先用正己烷溶解,然后用甲醇定容,其中正己烷含量为20%(v/v),用Hypersil ODS2 5μm色谱柱,甲醇为流动相,对所提油脂中维生素A、α-维生素E、γ-(β)维生素E、δ-维生素E含量进行检测。实验结果表明,在204nm波长下,维生素A、α-维生素E、γ-(β)维生素E、δ-维生素E在0~200μg/m L范围内与峰面积有良好的线性关系,标准曲线相关系数r均大于0.9978。维生素A、α-维生素E、γ-(β)维生素E、δ-维生素E加标平均回收率分别为97.83%、98.58%、98.75%、99.93%。  相似文献   

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This study identified practices, preferences, attitudes and decision-making for fruit consumption, fruit production, and use of income generated from these activities and assessed the contribution of fruits to closing nutritional gaps of members of smallholder farming households in Western Kenya during two different seasons. Two cross-sectional surveys were conducted, one in July/August 2013 (S1) and the other in February/March 2014 (S2). The same respondents, women responsible for food preparation in the household, were interviewed during S1 and S2 with a total of 272 women participating. Semi-structured questionnaires were used to collect data on practices, preferences and attitudes related to fruit production and consumption including a quantitative 24-h recall. On the day prior to the interview, only 25% of women during S1 and 37% during S2 had consumed fruits. Fruit consumption in grams per day differed significantly (p < 0.001) between the two seasons and was higher in S2 (mean = 106 g/d; SD = 208 g/d) compared to S1 (mean = 49 g/d; SD = 101 g/d). During both seasons, 80% or more respondents did not reach the recommended amount of 200 g of fruits per day and also had low vitamin A and C intakes, especially during S1. Simultaneously, 80% of women indicated that the household grew fruit, yet fruit production and consumption diversity were low. About 20% of respondents identified fruit consumption taboos for different household members and 37% viewed the consumption of wild fruits negatively. Integrated agriculture-nutrition programs should consider local practices, preferences and cultural attitudes in order to promote the consumption of a diversity of nutrient rich fruits and consequently better diets and nutrition.  相似文献   

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The prevalence of vitamin A deficiency (serum retinol [SR] < 20 microg/dl) in children from one to five years of age in the Philippines rose from 35.8% to 38% between 1993 and 1998, despite a twice-yearly universal vitamin A capsule distribution program. The Philippines 1998 National Nutrition Survey, with one-time SR measurements from 11,620 children from one to four years of age, collected over an eight-month period from one month to more than six months after distribution of vitamin A capsules, was an opportunity to examine the impact of the program on the children's vitamin A status, using post hoc analysis. Overall, a detectable impact of vitamin A capsules on SR was limited to groups with the highest prevalence of vitamin A deficiency and lasted up to four months after dose administration. In highly urban cities in Visayas, where very high prevalences of deficient SR (SR < 10 microg/dl) were found, the prevalence of deficient SR was reduced from 27% to 9% one to two months after distribution of vitamin A capsules, and to 16% at three to four months. In Mindanao, a statistically significant reduction from 38% to 32% was seen in the prevalence of deficient to low SR (SR < 20 microg/dl) one to four months after distribution of vitamin A capsules. There was no overall reduction in the prevalence of vitamin A deficiency or deficient and low SR (SR < 20 microg/dl) in Luzon, but a significant interaction with stunting was observed in Luzon non-highly urbanized cities. Two aspects are of concern. First, the magnitude of the effect of high-dose vitamin A capsules on SR, and hence on the extent of reduction in deficiency, is limited. Second, the effect does not persist for six months, which is the interval between doses. Thus there is no decrease in the prevalence of deficiency over time. With more frequent dosing (especially to those most deficient in SR), a progressive reduction in vitamin A deficiency could, however, be expected; this hypothesis could be tested. The policy implication arising from these results is that a shift in resources is warranted. In areas of low prevalence of vitamin A deficiency, distribution of vitamin A capsules should be targeted to stunted children. In areas of high prevalence, vitamin A capsules should be distributed to children one to five years old at least three times a year.  相似文献   

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BACKGROUND: Underweight and micronutrient deficiencies are sequelae of the prevailing harsh living and economic conditions of women in sub-Saharan Africa. There are few data describing maternal nutritional status in these resource-poor settings. Provision of more effective modes of intervention requires that public health and nutrition policy at both the national and the multisectoral levels be based on community-specific nutritional and behavioral practices. OBJECTIVE: This longitudinal study investigated maternal micronutrient status in two remote, semiarid, rural communities that are ethnically similar but have distinctly different pastoral and farming lifestyles. We looked at differences in iron stores, vitamin A levels, and body composition of women in the third trimester of pregnancy and again at 4 months postpartum. METHODS: Complete data were collected from 113 pastoral and 110 farming Pokot women. Anthropometric measurements were taken, and serum ferritin and retinol levels were measured. Infants were weighed within 7 days of birth. RESULTS: Women from the farming community had significantly (p < .05) lower hemoglobin concentrations than women from the pastoral community during the third trimester of pregnancy. Pastoral women had significantly higher serum ferritin concentrations than farming women during the third trimester of pregnancy (p <.05) and at 4 months postpartum. There were no significant differences between pastoral and farming women in the percentage of women with serum retinol levels < 0.70 micromol/L during the third trimester of pregnancy (27.9% [34/113] and 24.2% [31/110], respectively) and at 4 months postpartum (29.2% [33/113] and 30.9% [34/110]) In the farming community, mean infant birthweight was significantly lower (p <. 01) than in the pastoral community and a significantly higher (p < .05) proportion of newborns weighed less than 2.5 kg. At 4 months postpartum, the percentage of body fat was significantly lower in pastoral women than in farming women. CONCLUSIONS: Women from the farming community in West Pokot, Kenya, have lower iron stores during the third trimester of pregnancy than women in the pastoral community. In addition, the mean weight of their newborn infants is lower than that of infants in the pastoral community. These findings may be associated with differences in living conditions, which are usually harsher in farming than in pastoral communities.  相似文献   

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The actual nutrition of children in nurseries taking into account the losses of food substances during food cooking and realization is inadequate to the current physiological standards for all food substances, especially, with respect to vitamins and mineral elements. This inadequacy has been proved by the laboratory and clinical parameters of vitamin status of children. In the winter-summer period when vitamin deficiency in the rations is most pronounced, deviations in the content of vitamins and their metabolites in the blood and urine, as well as the incidence of hypovitaminosis symptoms in children are more frequently recorded and in the most pronounced form.  相似文献   

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This study assesses the arsenic (As) accumulation in different varieties of rice grain, that people in rural Bengal mostly prefer for daily consumption, to estimate the potential risk of dietary As exposure through rice intake. The rice samples have been classified according to their average length (L) and L to breadth (B) ratio into four categories, such as short-bold (SB), medium-slender (MS), long-slender (LS), and extra-long slender (ELS). The brown colored rice samples fall into the SB, MS, or LS categories; while all Indian Basmati (white colored) are classified as ELS. The study indicates that the average accumulation of As in rice grain increases with a decrease of grain size (ELS: 0.04; LS: 0.10; MS: 0.16; and SB: 0.33 mg kg(-1)), however people living in the rural villages mostly prefer brown colored SB type of rice because of its lower cost. For the participants consuming SB type of brown rice, the total daily intake of inorganic As (TDI-iAs) in 29% of the cases exceeds the previous WHO recommended provisional tolerable daily intake value (2.1 μg day(-1) kg(-1) BW), and in more than 90% of cases, the As content in the drinking water equivalent to the inorganic As intake from rice consumption (C(W,eqv)) exceeds the WHO drinking water guideline of 10 μg L(-1). This study further demonstrates that participants in age groups 18-30 and 51-65 yrs are the most vulnerable to the potential health threat of dietary As exposure compared to participants of age group 31-50 yrs, because of higher amounts of brown rice consumption patterns and lower BMI.  相似文献   

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A high speed liquid chromatographic method was described for the rapid determination of vitamin A in eggs. After saponification and extraction, the sample was separated on a reversed-phase column (C18) with acetonitrile - methylene-chloride - methanol as the mobile phase. Quantitative determination was accomplished by monitoring the ultraviolet absorbance of retinol at 280 nm. Recovery of vitamin A was 97.1 %.  相似文献   

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