电视屏幕闪烁对人体视觉调节功能影响的研究

目的 了解电视屏幕闪烁对人体视觉功能的不同影响。方法 选择视力正常的60名大学生为研究对象,采用眼调节近点、集合近点、视觉反应时、明视持久度、闪光融合临界频率的测定,了解观看无闪烁电视与普通电视3h前后人体视觉功能的变化。结果 观看3h无闪烁电视,受试视觉调节功能下降、视觉疲劳程度加大、注视的持久力减弱比观看普通电视要小。结论 视屏闪烁会影响视觉调节功能,可导致视觉系统紧张而出现视疲劳。     

叶黄素干预对长期荧屏光暴露者视功能的影响

目的研究叶黄素干预对长期荧屏光暴露者视功能的影响。方法采用双盲随机空白对照研究,将37名22～30岁长期荧屏光暴露者随机分为低剂量组、高剂量组和安慰剂组,分别每天给予6mg叶黄素、12mg叶黄素及安慰剂,连续干预12w。在干预前及干预后12w时,测定血清叶黄素浓度,并检测泪膜破裂时间,临界闪烁融合频率,明视持久度,视觉反应时等视功能指标。结果叶黄素干预后,高剂量组和低剂量组血清叶黄素(μmol/L)水平分别由0.328±0.120和0.356±0.117上升至0.733±0.354和0.607±0.176。高剂量组左眼泪膜破裂时间较干预前显著延长,明视持久度得到显著改善,平均简单反应时较干预前明显缩短;干预后临界闪烁融合频率、辨别反应时和选择反应时无明显变化。结论叶黄素干预对长期荧屏光暴露者泪膜破裂时间、明视持久度及简单反应时有明显改善作用。     

某中草药提取物改善学生视疲劳的效果观察

目的　评价某中草药提取物改善学生视力疲劳的效果。方法　选择 16～ 17岁在校自愿受试学生10 2人 ,随机分为试验组和安慰剂对照组 ,试验组服用某中草药提取物制成的保健食品 ,按照产品说明书的要求食用 4 5天 ,以食用前后的眼部自觉症状总积分、远视力和明视持久度作为主要功效观察指标。结果　试验组的眼痛、眼胀、畏光、视力模糊、干涩等症状明显改善 ,试验组的眼部症状总积分与对照组及实验前后比较差异均有极显著性 (P<0 .0 1) ;试验组的明视持久度有明显提高 ,与对照组及实验前后比较差异均有极显著性(P<0 .0 1) ;试验组缓解视力疲劳的总有效率达 73.1% ,与对照组比较差异有极显著性 (P<0 .0 1)。结论　该中草药提取物制成的保健食品具有明显改善视疲劳的作用。     

槟榔加工业作业人员视觉疲劳影响的研究

目的了解槟榔加工业作业人员视觉疲劳情况。方法选择从事槟榔加工的56名作业人员,测定他们在工作前、工作中、工作结束时的明视持久度,运动反应时,并分析测试结果的变化率。结果观察组临床症状和体征阳性率显著高于对照组(P<0.05)。选籽、切籽与点卤作业工人明视持久度、视觉运动反应时显著高于对照组(P<0.05)。结论槟榔加工业对作业人员的视觉疲劳有一定的影响。     

从事精细作业工人的视机能调查

本文对印刷和纺织厂精细作业工人进行了视力和明视持久度的调查,结果:作业工人的远、近视力比对照组明显下降(P<0.05);班前、班后明视持久度相比,也有明显差异(P<0.05);工作后头痛、头晕、视物不清的出现率较高。说明精细作业工人视力机能的减退较明显,应引起重视。本文还讨论了视疲劳的预防性措施。     

某石油化工公司集散控制系统操作人员视觉疲劳影响的研究

目的：了解集散控制系统（DCS：distributed control system）操作人员视觉疲劳情况。方法：以某石化公司从事DCS操作的人员79名作为观察组；而以同一车间同一班次的非DCS操作人员（主要是对DCS操作的人员发生的指令进行户外操作的人）95名作为对照组，分别测定其在早、中、前夜，后夜4班次的班前和班后的明视持久度，运动反应时，闪光融合频率，远、近点调节4项指标，分析测试结果的变化率。结果：观察组与对照组在前3项指标和右眼远，近点调节差异有显著性（P＜0．01），左眼远，近点调节和集合近点调节在观察组和对照组之间差异也有显著性（P＜0．05）；比较不同班次的观察组和对照组的结果显示，明视持久度，视觉运动反应时，闪光融合频率，近点调节在观察组与对照组之间差异有显著性。结论：DCS对操作人员的视觉疲劳有一定的影响。     

越橘提取物复合维生素A对改善视疲劳的实验研究

目的:研究越橘提取物复合维生素A对改善视疲劳的作用。方法:选择视力易疲劳的受试者120名,分为试食组和安慰组,每组60人,试食组口服越橘提取物复合维生素A每日2次,每次1粒,对照组口服颜色、性状与越橘提取物复合维生素A胶囊相同的安慰剂,食用量同试食组,试验期限为30 d。然后进行下列检查:常规观察、安全性检查、眼部症状检查、观察眼部自觉症状、眼科常规检查、明视持久度测定、视力检查。结果:30 d后试食组视疲劳明显减轻,双眼明视持久度平均提高13.23%±10.34%,总有效率51.9%,对照组明视持久度平均提高1.39%±4.74%,总有效率5.8%,经统计学处理差异有显著性。结论:研究表明越橘提取物复合维生素A能有效缓解人体视疲劳。     

长途汽车司机色觉疲劳调查

随着社会主义市场经济的迅速发展,交通运输业十分繁忙,控制与预防交通事故的发生频率及其伤损度是当今人们普遍关注的问题。长途汽车司机在驾车过程中常处于雾、阴、雨天、夜间等低照明视力、高度紧张状态下行驶,久之易发生视觉、色觉疲劳,使迅速辨识各种颜色的能力下降。国内外对飞行员、火车司机、机动车驾驶员的视觉疲劳方面进行过一些研究,而在色觉疲劳尤其对迅速辨识可视光临界融合频率及年龄阈值研究甚少,因此,我们以长途汽车司机为研究对象,采用三色闪烁融     

首都雷达操纵人员视觉疲劳防护措施的效果

目的 探讨视觉疲劳综合防护措施对空军某地面雷达操纵人员视觉疲劳的防护效果.方法 以首都空军某部队雷达操纵人员共30例为对象,在应用视觉疲劳防护措施前后分别进行临界闪光融合频率(CFF)检测、眼部视力、结膜炎等不适症状检查.视觉防护措施效果观察采用主观评价问卷调查和眼部检查,并进行前后对比分析.结果 综合防护措施防护后,除眼睑沉重和眼睛干涩外,眼睛酸胀、眼痛、流泪、畏光、充血、视物模糊、视力下降和结膜炎等眼部不适症状较防护前明显减轻,差异有统计学意义(P＜0.01);视觉防护措施应用前后,CFF的差异亦有统计学意义(t=3.499.P＜0.01).结论 视觉疲劳综合防护措施对首都空军雷达操纵人员视觉疲劳具有明显的防护效果.     

首都雷达操纵人员视觉疲劳防护措施的效果

目的 探讨视觉疲劳综合防护措施对空军某地面雷达操纵人员视觉疲劳的防护效果.方法 以首都空军某部队雷达操纵人员共30例为对象,在应用视觉疲劳防护措施前后分别进行临界闪光融合频率(CFF)检测、眼部视力、结膜炎等不适症状检查.视觉防护措施效果观察采用主观评价问卷调查和眼部检查,并进行前后对比分析.结果 综合防护措施防护后,除眼睑沉重和眼睛干涩外,眼睛酸胀、眼痛、流泪、畏光、充血、视物模糊、视力下降和结膜炎等眼部不适症状较防护前明显减轻,差异有统计学意义(P＜0.01);视觉防护措施应用前后,CFF的差异亦有统计学意义(t=3.499.P＜0.01).结论 视觉疲劳综合防护措施对首都空军雷达操纵人员视觉疲劳具有明显的防护效果.     

Motivational and Parental Mediation Factors Related to Kenyan Adolescents’ Intake of Sexual Radio and TV Content

Research on the influence of media on youths’ sexual behavior in sub-Saharan Africa has focused almost entirely on the effects of multimedia health communication campaigns and edutainment programming. Scholarly literature is nearly silent about the influence of the multiple hours that young people in many sub-Saharan nations spend immersed in increasingly sex-heavy entertainment programming. We surveyed a stratified cluster sample of 437 Nairobi public high school students about motivational and parental mediation factors associated with their exposure to sexual radio and TV content. Watching sexual content in the bedroom predicted higher intake of both sexual radio and TV content. Believing that parents were successful in their efforts to limit media use predicted lower intake of both sexual radio and TV content. A friend/companion motive for watching was associated with taking in higher levels of sexual TV content. For day school students, watching sexual content in the sitting room also predicted higher levels of exposure to sexual TV content.     

TV Viewing,Independent of Physical Activity and Obesogenic Foods,Increases Overweight and Obesity in Adolescents

The aim of this study was to estimate the prevalence of overweight and obesity (OAO) and associated risk factors in a representative sample of students aged 11-20 years in Urmia, Iran. In this population-based cross-sectional study, a multistage random cluster-sampling method was used, through which 2,498 students were selected. OAO were defined based on criteria set by the US Center for Health Statistics in collaboration with the US Center for Chronic Disease Prevention and Health Promotion under the Centers for Disease Control and Prevention (CDC). OAO risk factors were assessed using a questionnaire containing questions about TV viewing, nutrition, physical activities (PA), social and economic factors. Contents of the questionnaire were validated by calculating the content validity ratio (CVR) and content validity index (CVI), based on the responses elicited from 15 experts. Reliability of the questionnaire was obtained from a test and re-test of the questionnaire completed by 15 students. To analyze the data, χ²-test, t-test, and multiple logistic regression analysis were conducted. The prevalence of OAO was found to be 14.1% among the 11-20 years old students of junior and senior high schools. The results of multiple logistic regression analysis indicated that the educational level of mothers, type of school, and the time spent on viewing TV were associated with an increased risk of OAO while obesogenic foods and PA had no effect on the frequency of OAO [Odds ratio (OR) for the time spent on watching TV one hour more than usual equals 1.27 at p=0.001]. The direct correlation between TV viewing and OAO, which is independent of PA and obesogenic foods, needs to be carefully investigated through randomized clinical trials and cohort studies.Key words: Adolescents, Obesity, Overweight, TV viewing, Iran     

Risk factors for reduced visual acuity in female junior high school students: findings of a cross-sectional study

PURPOSE: The purpose was to explore the risk factors for reduced visual acuity in female junior high school students that are relevant to their living habits/environment. METHODS: A cross-sectional survey was conducted to collect data on the living habits/environment and visual acuity of female junior high school students. All the variables measured in the study were categorized into multiple, mostly two, categories, since distributions of data that are obtained at school medical examinations are often right-skewed with possible outliers; in particular, application of accurate measurement of visual acuity such as the method of refractive power was not feasible. Multiple logistic regression was employed in the analysis of data, incorporating the graphical modelling technique. Akaike Information Criteria (AIC) was used to select the best model fit for the data. RESULTS: The odds ratio for students watching TV from less than a 2 m distance relative to more than 2 m was 2.08 (95%CI 1.23-3.50) and statistically significant, after adjustment for the study time at home/cram school, reading time, sleeping time, and use of glasses/contact lenses by parents/siblings. On the other hand, after the same adjustment, the odds ratio for students watching the TV for 2 h or more relative to those watching the TV for less than 2 h was close to unity and not even selected in the final model. The results also indicated that study time at home/cram school, reading time, and use of glasses/contact lenses by parents/siblings are significantly associated with reduced visual acuity. The risks of combinations of these variables were evaluated by means of the odds ratios. CONCLUSION: We found several risk factors that are responsible for reduced visual acuity in female junior high school students. It is considered that the distance of TV viewing is the most important and yet relatively amenable to intervention for improvement to avoid reduction in visual acuity. Multivariate evaluation of the risks for visual acuity decrease was possible by means of odds ratios. Concrete suggestions can thus be made to female junior high school students to prevent decrease of visual acuity by changing the living habits/environment.     

Comparing Local TV News with National TV News in Cancer Coverage: An Exploratory Content Analysis

The authors compared local TV news with national TV news in terms of cancer coverage using a nationally representative sample of local nightly TV and national network TV (i.e., ABC, CBS, NBC, and CNN) cancer news stories that aired during 2002 and 2003. Compared with national TV news, local TV cancer stories were (a) much shorter in length, (b) less likely to report on cancer prevention (i.e., preventive behaviors and screening tests), and (c) less likely to reference national organizations (i.e., National Cancer Institute, American Cancer Society, National Institutes of Health, Centers for Disease Control and Prevention, Food and Drug Administration) that have made clear recommendations about ways to prevent cancer. The implications of these findings for health communication research and cancer education were discussed.     

The audience of TV health programs

The viewing figures of 36 unpaid TV health programs was assessed: the number of viewers, their socio-demographic status and interest in specific program. Between June 1998 and June 1999, non commercial TV health programs reached 0.7% to 7.6% TV audience, no more than 2,700.000 viewers per program. Programs broadcasted in evenings and winter time had more viewers. The audience consisted usually of: women, retired persons, rural inhabitants, persons with basic educational background. Pensioners were interested in every program, women in majority. Students, blue-collar workers and men were censorious and appreciated some programs only.     

Physical activity,TV viewing,and weight in U.S. youth: 1999 Youth Risk Behavior Survey

OBJECTIVE: To examine the relationship between physical activity, TV watching, and weight in U.S. youth ages 14 to 18 years. RESEARCH METHODS AND PROCEDURES: Data from a nationally representative sample of 15,143 U.S. high-school students participating in the 1999 Centers for Disease Control and Prevention (CDC) Youth Risk Behavior Survey were examined. Prevalence rates of participation in moderate physical activity (MPA), vigorous physical activity (VPA), and television watching (TV) were determined. The association between MPA, VPA, TV and the body mass index (BMI) and overweight status (BMI > or =85th percentile of age- and sex-specific CDC/National Center for Health Statistics reference values) were examined by analysis of covariance and logistic regression. RESULTS: Overall, 45% reported participating in MPA > or =3 d/wk, 65% reported participating in VPA > or =3 d/wk, and 25% reported watching TV > or =4 h/school day. Boys reporting six to seven bouts of MPA had a significantly lower BMI compared with boys reporting three to five or less than two. The mean BMI differed significantly between the lowest and highest levels of MPA groups in girls. The mean BMI was significantly lower in the highest VPA group compared with the other two groups in both sexes. There was a significant graded response for BMI across all levels of TV. Decreased levels of MPA and 3 to 4 days of VPA were significantly associated with an increased risk of overweight in boys when compared with those engaging in 6 to 7 d/wk (odds ratio = 1.26 to 1.37). A graded response existed between TV and overweight in both sexes. Boys and girls were approximately 20% to 25% less likely to be classified as overweight if they reported 2 to 3 hours of TV per day and approximately 40% less likely to be classified as overweight if they reported < or =1 hour of TV per day compared with those who watched > or =4 hours of TV. In general, youth who engaged in less physical activity watched more TV per week. DISCUSSION: Increased levels of physical activity are associated with a lower BMI and less TV watching. However, the relationship between TV watching and weight status is more pronounced.     

TV on the Web

Children's Hospital & Research Center of Oakland, CA, launched a TV campaign focusing on athletic children to promote its excellent pediatric care. The TV campaign is also featured on the hospital's Web site. There are also five 15-second spots that offer parents handy tips on how to deal with injuries faced by an athletic child.     

Can sedentary behavior be made more active? A randomized pilot study of TV commercial stepping versus walking

ABSTRACT: BACKGROUND: There is a growing problem of physical inactivity in America, and approximately a quarter of the population report being completely sedentary during their leisure time. In the U.S., TV viewing is the most common leisure-time activity. Stepping in place during TV commercials (TV Commercial Stepping) could increase physical activity. The purpose of this study was to examine the feasibility of incorporating physical activity (PA) into a traditionally sedentary activity, by comparing TV Commercial Stepping during 90 min/d of TV programming to traditional exercise (Walking). METHODS: A randomized controlled pilot study of the impact of 6 months of TV Commercial Stepping versus Walking 30 min/day in adults was conducted. 58 sedentary, overweight (body mass index 33.5 +/- 4.8 kg/m2) adults (age 52.0 +/- 8.6 y) were randomly assigned to one of two 6-mo behavioral PA programs: 1) TV Commercial Stepping; or 2) Walking 30 min/day. To help facilitate behavior changes participants received 6 monthly phone calls, attended monthly meetings for the first 3 months, and received monthly newsletters for the last 3 months. Using intent-to-treat analysis, changes in daily steps, TV viewing, diet, body weight, waist and hip circumference, and percent fat were compared at baseline, 3, and 6 mo. Data were collected in 2010-2011, and analyzed in 2011. Results: Of the 58 subjects, 47 (81%) were retained for follow-up at the completion of the 6-mo program. From baseline to 6-mo, both groups significantly increased their daily steps [4611 +/- 1553 steps/d vs. 7605 +/- 2471 steps/d (TV Commercial Stepping); 4909 +/- 1335 steps/d vs. 7865 +/- 1939 steps/d (Walking); P<0.05] with no significant difference between groups. TV viewing and dietary intake decreased significantly in both groups. Body weight did not change, but both groups had significant decreases in percent body fat (3-mo to 6-mo), and waist and hip circumference (baseline to 6-mo) over time. CONCLUSIONS: Participants in both the TV Commercial Stepping and Walking groups had favorable changes in daily steps, TV viewing, diet, and anthropometrics. PA can be performed while viewing TV commercials and this may be a feasible alternative to traditional approaches for increasing daily steps in overweight and obese adults. Trial Registration: This study is registered at ClinicalTrials.gov, NCT01342471.     

A Portrait of Food and Drink in Commercial TV Series

This study examines the content and presentation of food and drink on fictional, commercial television. It provides the first comparison of food and drink consumption across different television program genres designated for different age groups. Data originated with a random sample of 50 taped episodes of children's shows, 50 episodes of “tween” programs (shows targeted for 9- to 14-year-olds), 40 episodes of afternoon soaps, and 50 episodes of prime time shows. The choice of TV series was based solely on the strength of Nielsen audience ratings. The study coded the foods for nutritional content and the drinks for alcoholic/nonalcoholic content, how they were used, and in what context. Findings indicate that foods were more commonly offered and consumed on children's shows, and that problematic foods (defined as oils, solid fats, and foods with added sugars) were significantly more prevalent in youth-oriented shows than in adult-oriented shows. Although there was only a negligible presence of alcohol on children's shows, the average hourly use of alcohol on the tween shows matched that of the adult programs; therefore, alcohol was as common in the shows directed at young audiences as in shows for adults. Negative outcomes were largely absent from food and drink behaviors on these TV series.     

Beliefs About Child TV Viewing in Low-Income Mexican American Parents of Preschoolers: Development of the Beliefs About Child TV Viewing Scale (B-TV)

Objectives Parental beliefs about child television viewing may affect the way parents regulate child television viewing. Despite this, little research has focused on the development of measures of parental beliefs about child television viewing, particularly among ethnic minority parents and parents of young children. This study’s objective was to develop and test a culturally-based measure of parental beliefs about television viewing in low-income Mexican American mothers of preschoolers. Methods Using a cross-sectional study design, 22 items reflecting parental beliefs about influences of TV on children were developed and assessed for psychometric properties in a sample of 312 low-income Mexican American mothers of preschoolers. Results Using exploratory factor analysis, we identified four factors reflecting four domains of parental beliefs: positive general beliefs, positive sleep-related beliefs, positive functional beliefs, and negative general beliefs. Internal reliabilities were acceptable (Cronbach’s alpha?=?0.70–0.89) for all factors except negative general beliefs (Cronbach’s alpha?=?0.61). Positive sleep-related beliefs and Positive Functional Beliefs were correlated with children’s average daily hours of TV (r?=?0.16, p?<?.01; r?=?0.22, p?<?.001, respectively) and with mother’s average daily hours of TV (r?=?0.14, p?<?.05; r?=?0.22, p?<?.001, respectively), providing initial support for construct validity. Conclusions for Practice The Beliefs about Child TV viewing scale measures four domains of parental beliefs regarding child TV viewing, and has good initial reliability and validity for three factors. Future use will allow investigators to conduct more in-depth evaluations on the influence of parental beliefs on the way parents shape their child’s use of the TV.