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OBJECTIVE: To investigate the effect of television food advertising on children's food intake, specifically whether childhood obesity is related to a greater susceptibility to food promotion. DESIGN: The study was a within-subject, counterbalanced design. The children were tested on two occasions separated by two weeks. One condition involved the children viewing food advertisements followed by a cartoon, in the other condition the children viewed non-food adverts followed by the same cartoon. Following the cartoon, their food intake and choice was assessed in a standard paradigm. SETTING: The study was conducted in Liverpool, UK. SUBJECTS: Fifty-nine children (32 male, 27 female) aged 9-11 years were recruited from a UK school to participate in the study. Thirty-three children were normal-weight (NW), 15 overweight (OW) and 11 obese (OB). RESULTS: Exposure to food adverts produced substantial and significant increases in energy intake in all children (P < 0.001). The increase in intake was largest in the obese children (P = 0.04). All children increased their consumption of high-fat and/or sweet energy-dense snacks in response to the adverts (P < 0.001). In the food advert condition, total intake and the intake of these specific snack items correlated with the children's modified age- and gender-specific body mass index score. CONCLUSIONS: These data suggest that obese and overweight children are indeed more responsive to food promotion, which specifically stimulates the intake of energy-dense snacks.  相似文献   

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OBJECTIVES: There has been surprisingly little research into the effects of food advertising on parents' perception of commonly consumed children's food items, although the available research suggests that parents may find nutritional claims in these advertisements confusing. The purpose of the present study was to investigate parents' perceptions of branded snack foods targeted at children, and the extent to which these perceptions are influenced by advertising messages. DESIGN: Using an intercept survey, participants were shown either adult-targeted or child-targeted advertisements for the same food products. SETTING: Central business district of a major Australian city. SUBJECTS: One hundred adults, mean age 40 years. RESULTS: The study results suggest that: (1) adults' perceptions of advertised food products and, most importantly, purchase intentions for those products differ according to the version of the advertisement seen (for three of the products, 42-54% would buy the product after seeing the child version compared with 82-84% after seeing the adult version); and (2) adults clearly perceive distinctly different messages in advertisements for the same products which are targeting parents vs. those targeting children (e.g. for three of the products, 74-92% perceived that the adult version of the advertisement suggested the food was nutritionally beneficial compared with 2-14% perceiving this for the child version). CONCLUSIONS: It is clear that the messages conveyed to children about specific foods are quite different to the messages conveyed to adults - and importantly parents - about the same foods.  相似文献   

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为了促进江西广大农村地区的信息化建设,丰富广大农民的文化生活,该文根据江西农村大部分地区的地形地貌特点以及江西广播电视系统目前的发展状况,提出了一套基于单频网国标地面数字电视系统的建设方案,包括全省电视网的设计目标和统一布局提案,各地发射站点的前端系统的设置,单频网发射系统参数的选择、覆盖效果预测及将来测试的方案,以及接收系统的构成;针对主站和辅站覆盖不到的地区,提出了补点覆盖宽带发射系统的具体实施方案。这套系统可开展转播CCTV和各省市卫视节目、转播境外卫视节目、支持地方新闻现场直播、电子节目指南插入等业务,使该数字业务电视平台成为一个先进的、实用的、可持续发展的多功能业务平台,旨在为江西广大农村和偏远山区的新农村信息化建设和发展提供既科学又经济可靠的参考。  相似文献   

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OBJECTIVE: To examine the relationship between television (TV) viewing and body mass index (BMI) among adolescents in a region of mainland China. DESIGN: Population-based cross-sectional study, conducted between September and November of 2004, on a sample of enrolled high-school students aged 12-18 years. SETTING: One hundred and sixty-eight classes randomly selected from both urban and rural areas and belonging to 15 senior and 41 junior high schools in Nanjing, China, with a regional population of 6.0 million. SUBJECTS: In total 6848 students participated; 47.7 % from urban and 52.3 % from rural areas; 49.0 % male and 51.0 % female. The response rate among eligible participants was 89.3 %. RESULTS: The proportion of overweight was 6.6 % according to the criteria of overweight recommended for Chinese adolescents. Boys than girls (8.9 % vs. 4.4 %) had higher odds of being overweight (odds ratio (OR) 2.12, 95 % confidence interval (CI) 1.74, 2.60), while the proportion of overweight was significantly lower among rural students than urban students (4.5 % vs. 8.9 %; OR 0.49, 95 % CI 0.40, 0.60). Those students who watched TV for more than 7 h/week had a 1.5 times greater odds of being overweight relative to their counterparts who watched TV for 7 h/week or less (adjusted OR 1.51, 95 % CI 1.24, 1.82). Furthermore, there was a positive linear relationship between TV viewing time and BMI, even after adjusting for age, gender, residence area, time spent in study, in sleeping and in physical activity, and monthly pocket money. CONCLUSIONS: Viewing TV might increase the likelihood of being overweight for Chinese adolescents in China.  相似文献   

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OBJECTIVES: To evaluate the feasibility of the UK Nutrient Profile (NP) model for identifying 'unhealthy' food advertisements using a case study of New Zealand television advertisements. DESIGN: Four weeks of weekday television from 15.30 hours to 18.30 hours was videotaped from a state-owned (free-to-air) television channel popular with children. Food advertisements were identified and their nutritional information collected in accordance with the requirements of the NP model. Nutrient information was obtained from a variety of sources including food labels, company websites and a national nutritional database. RESULTS: From the 60 h sample of weekday afternoon television, there were 1893 advertisements, of which 483 were for food products or retailers. After applying the NP model, 66 % of these were classified as advertising high-fat, high-salt and high-sugar (HFSS) foods; 28 % were classified as advertising non-HFSS foods; and the remaining 2 % were unclassifiable. More than half (53 %) of the HFSS food advertisements were for 'mixed meal' items promoted by major fast-food franchises. The advertising of non-HFSS food was sparse, covering a narrow range of food groups, with no advertisements for fresh fruit or vegetables. CONCLUSIONS: Despite the NP model having some design limitations in classifying real-world televised food advertisements, it was easily applied to this sample and could clearly identify HFSS products. Policy makers who do not wish to completely restrict food advertising to children outright should consider using this NP model for regulating food advertising.  相似文献   

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OBJECTIVES: To explore how time spent watching television (TV) is associated with the dietary behaviours of New Zealand children and young adolescents. DESIGN: Secondary data analysis of a nationally representative, cross-sectional survey. SETTING: In homes or schools of New Zealand school students. PARTICIPANTS: In total, 3275 children aged 5 to 14 years. RESULTS: The odds of being overweight or obese increased with duration of TV viewing for children and adolescents when controlling for age, sex, ethnicity, socio-economic status and physical activity. Children and adolescents who watched the most TV were significantly more likely to be higher consumers of foods most commonly advertised on TV: soft drinks and fruit drinks, some sweets and snacks, and some fast foods. Both children and adolescents watching two or more hours of TV a day were more than twice as likely to drink soft drinks five times a week or more (P = 0.03 and P = 0.04, respectively), eat hamburgers at least once a week (both P = 0.02), and eat French fries at least once a week (both P < 0.01). CONCLUSIONS: These findings suggest that longer duration of TV watching (thus, more frequent exposure to advertising) influences the frequency of consumption of soft drinks, some sweets and snacks, and some fast foods among children and young adolescents. Efforts to curtail the amount of time children spend watching TV may result in better dietary habits and weight control for children and adolescents. Future studies examining the impact of advertising on children's diets through interventions and international comparisons of legislation would provide more definitive evidence of the role of advertising in child and adolescent obesity.  相似文献   

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Purpose

Rice-paddy-dominated watersheds in eastern China are intensively cultivated, and lands with two crops receive as much as 550–600 kg?ha–1?year–1 of nitrogen (N), mainly through the addition of N-based fertilizers. However, stream N concentrations have been found to be relatively low. Waterways in the watersheds are assumed to be effective “sinks” for N, minimizing its downstream movement. We directly measured net sediment denitrification rates in three types of waterways (ponds, streams/rivers, and a reservoir) and determined the key factors that control net sediment denitrification. Such information is essential for evaluating the impact of the agricultural N cycle on the quality of surface water.

Materials and methods

The pond–stream–reservoir continuum was sampled every 2 months at nine sites in an agricultural watershed between November 2010 and December 2011. Net sediment N2 fluxes/net sediment denitrification rates were determined by membrane inlet mass spectrometry and the N2/Ar technique. A suite of parameters known to influence denitrification were also measured.

Results and discussion

Net denitrification rates ranged between 28.2?±?18.2 and 674.3?±?314.5 μmol N2–N?m–2?h–1 for the streams, 23.7?±?23.9 and 121.2?±?38.7 μmol N2–N?m–2?h–1 for the ponds, and 41.8?±?17.7 and 239.3?±?49.8 μmol N2–N?m–2?h–1 for the reservoir. The mean net denitrification rate of the stream sites (173.2?±?248.4 μmol N2–N?m–2?h–1) was significantly higher (p?<?0.001) than that of the pond sites (48.3?±?44.5 μmol N2–N?m–2?h–1), and the three types of waterways all had significantly higher (p?<?0.01) mean net denitrification rates in summer than in other seasons. Linear regression and linear mixed effect model analysis showed that nitrate (NO3 ?–N) concentration in surface water was the primary controlling factor for net sediment denitrification, followed by water temperature. Using monitoring data on NO3 ?–N concentrations and temperature of the surface water of waterways and an established linear mixed effect model, total N removed through net sediment denitrification in the pond–stream–reservoir continuum was estimated at 46.8?±?24.0 t?year–1 from July 2007 to June 2009, which was comparable with earlier estimates based on the mass balance method (34.3?±?12.7 t?year–1), and accounted for 83.4 % of the total aquatic N. However, the total aquatic N was only 4.4 % of the total N input to the watershed, and thus most of the surplus N in the watershed was likely to be either denitrified or stored in soil.

Conclusions

High doses of N in a rice-paddy-dominated watershed did not lead to high stream N concentrations due to limited input of N into waterways and the high efficiency of waterways in removing N through denitrification.  相似文献   

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Phytoremediation is an emerging technology based on the use of green plants to remove, contain, inactivate or destroy harmful environmental pollutants. Recent developments in Europe and the USA show that the approach is somewhat different on both sides of the Atlantic. In Europe, phytoremediation has more basically been research driven and, based on the outcomes, applications have been envisaged. By contrast, the approach in the USA is more application and experience driven. In spite of a growing track record of commercial success, more demonstration projects are needed to prove that phytoremediation is effective in order to rigorously measure its underlying economics, and to expand its applications. More fundamental research is also required to better understand the complex interactions between pollutants, soil, plant roots and micro-organisms at the rhizosphere level, to increase the bioavailability of pollutants, to fully exploit the metabolic diversity of plants and, thus, to successfully implement this new green technology.  相似文献   

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Trace metals (Cd, Cu, Fe, Mn, Pb, and Zn) concentrations in atmospheric precipitation have been routinely monitored in Sweden since the autumn of 1983. Concentrations are highest in southern Sweden and decrease northward. It is postulated that the long range transport of anthropogenic pollutants from the rest of Europe is the major source of Cd, Pb, and Zn in precipitation. Evidence for this hypothesis is that enrichment factors indicate anthropogenic origin, and Swedish atmospheric emissions of Zn and Cd are 2 to 3 times smaller than deposition fluxes. Also, Cd, Pb, and Zn concentrations are correlated in both space and time and are also well correlated with exSO4 +, a substance known to be of anthropogenic origin transported long distances.  相似文献   

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Water, Air, & Soil Pollution - Epiphytic lichens were sampled in a Dutch national monitoring survey, which was carried out twice within 5 yr. The samples were analyzed by neutron activation...  相似文献   

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中国华北地区近40年物候春季变化   总被引:17,自引:4,他引:17  
根据华北地区7个观测站物候资料,分析了华北地区1963-1996年及北京1963-2005年物候春季的变化特征及其与气温的关系。结果表明:华北地区的物候春季有明显提早来临的趋势,而造成这一变化的主要因素是本地区近40 a来冬春季气温的明显上升。其中1963-1996年间华北地区1-3月及4月的平均气温分别上升了2.3℃与1.7℃,物候春季起止日期分别提前了9d和4d,因而使得春季长度也延长了5d;北京1963-2003年间1-3月及4月的平均气温分别上升了3.5℃与2.6℃,物候春季的起止日期分别提前了11d和10d,但春季长度没有明显变化。  相似文献   

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对天津周边半干旱地区不同种植年限的菜田土壤微生物状况调查研究表明 ,该地区土壤微生物以细菌为主 ,夏季微生物总量大大高于冬季 ;随着种菜年限的增加 ,耕层和亚耕层微生物总量都有增加趋势 ,其中细菌和放线菌增加明显 ,真菌有下降趋势 ;真菌类群分析表明 ,少数纤维素分解菌 ,如青霉 (Penicillium)、木霉 (Trichoderma)等为优势菌 ,而糖和木质素分解菌仅占少数。用尖孢镰刀霉 (Fusariumuoxysporum)、大肠杆菌 (Escherichia coli)接种不同种菜年限土壤 ,检测土壤拮抗菌状况发现 ,拮抗菌仅在种植年限长的老菜田的放线菌中发现。表明北方半干旱地区菜田土壤细菌为优势菌 ,主要存在于土壤微孔隙中 ;而适于生活在土壤疏松大孔隙中的真菌数量极少。应注意土壤结构的改良 ,为丰富土壤微生物提供良好的生态环境  相似文献   

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对天津周边半干旱地区不同种植年限的菜田土壤微生物状况调查研究表明 ,该地区土壤微生物以细菌为主 ,夏季微生物总量大大高于冬季 ;随着种菜年限的增加 ,耕层和亚耕层微生物总量都有增加趋势 ,其中细菌和放线菌增加明显 ,真菌有下降趋势 ;真菌类群分析表明 ,少数纤维素分解菌 ,如青霉 (Penicillium)、木霉 (Trichoderma)等为优势菌 ,而糖和木质素分解菌仅占少数。用尖孢镰刀霉 (Fusariumuoxysporum)、大肠杆菌 (Escherichia coli)接种不同种菜年限土壤 ,检测土壤拮抗菌状况发现 ,拮抗菌仅在种植年限长的老菜田的放线菌中发现。表明北方半干旱地区菜田土壤细菌为优势菌 ,主要存在于土壤微孔隙中 ;而适于生活在土壤疏松大孔隙中的真菌数量极少。应注意土壤结构的改良 ,为丰富土壤微生物提供良好的生态环境  相似文献   

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沈阳市城市表土中微生物区系变化的初步研究   总被引:2,自引:0,他引:2  
在沈阳市远郊-近郊-市区等不同城市化水平区内选取林地、草地和路边土几种不同利用方式下的表层土壤,对土壤中的微生物状况进行了初步分析。结果表明,随着城市化水平的提高,土壤中微生物的数量表现为明显的减少趋势。其中变化较大的是细菌,而真菌和放线菌的变化不明显。  相似文献   

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