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101.
Objectives: To determine if macronutrient consumption for the U.S. population is greater on weekend days than weekdays. Research Methods and Procedures: The nationally representative 1994 to 1996 Continuing Survey of Food Intakes by Individuals was used for this analysis. Dietary intake was assessed using two independent days of dietary recall data. Ordinary least squares multivariate analysis was used to analyze dietary outcome variables to explore the effect of weekend day vs. weekday intake. Results: This study's results indicate that statistically significant dietary intake differences occur for different days of the week but not for all age groups—nor for all nutrients. The average American, 2 years and older, consumes 82 kcal more per day on each weekend day (Friday through Sunday) than they do on weekdays (Monday through Thursday). These overall increases in dietary intake are significant for the overall sample and are largest for the 19‐ to 50‐year‐old age group; among this age group, the weekend day increase (vs. weekday) is 115 kcal/d. The increased proportions of energy from fat and alcohol consumed on weekends are greater for this adult age group by 0.7% and 1.4%, respectively, whereas the proportion of energy from carbohydrate decreases 1.6%. Discussion: The effects of weekend days on nutrient intake are substantial and should be considered in future clinical and population‐based interventions and in dietary monitoring and research in the U.S.  相似文献   
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Objective: To determine the trends in locations and food sources of Americans stratified by age group for both total energy and the meal and snack subcomponents. Research Methods and Procedures: Nationally representative data was taken from the 1977 to 1978 Nationwide Food Consumption Survey and the 1989 to 1991 and 1994 to 1996 (and 1998 for children age 2 through 9) Continuing Surveys of Food Intake by Individuals. The sample consisted of 63,380 individuals, age 2 and up. For each survey year, the percentage of total energy intake from meals and snacks was calculated separately for 2‐ to 18‐year‐olds, 19‐ to 39‐year‐olds, 40‐ to 59‐year‐olds, and those 60 years and older. The percentage of energy intake by location (at‐home consumption or preparation, vending, store eaten out, restaurant/fast‐food, and school) and by specific food group was computed for all age groups separately. Results: The trends in location and food sources were almost identical for all age groups. Key dietary behavior shifts included greater away‐from‐home consumption; large increases in total energy from salty snacks, soft drinks, and pizza; and large decreases in energy from low‐ and medium‐fat milk and medium‐ and high‐fat beef and pork. Discussion: Total energy intake has increased over the past 20 years, with shifts away from meals to snacks and from at‐home to away‐from‐home consumption. The similarity of changes across all age groups furthers the assertion that broad‐based environmental changes are needed to improve the diets of Americans.  相似文献   
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BackgroundIn an effort to prevent and reduce the prevalence rate of people with obesity and diabetes, South Africa implemented a sugar-content-based tax called the Health Promotion Levy in April 2018, one of the first sugar-sweetened beverage (SSB) taxes to be based on each gram of sugar (beyond 4 g/100 ml). This before-and-after study estimated changes in taxed and untaxed beverage intake 1 year after the tax, examining separately, to our knowledge for the first time, the role of reformulation distinct from behavioral changes in SSB intake.Methods and findingsWe collected single-day 24-hour dietary recalls from repeat cross-sectional surveys of adults aged 18–39 years in Langa, South Africa. Participants were recruited in February–March 2018 (pre-tax, n = 2,459) and February–March 2019 (post-tax, n = 2,489) using door-to-door sampling. We developed time-specific food composition tables (FCTs) for South African beverages before and after the tax, linked with the diet recalls. By linking pre-tax FCTs only to dietary intake data collected in the pre-tax and post-tax periods, we calculated changes in beverage intake due to behavioral change, assuming no reformulation. Next, we repeated the analysis using an updated FCT in the post-tax period to capture the marginal effect of reformulation. We estimated beverage intake using a 2-part model that takes into consideration the biases in using ordinary least squares or other continuous variable approaches with many individuals with zero intake. First, a probit model was used to estimate the probability of consuming the specific beverage category. Then, conditional on a positive outcome, a generalized linear model with a log-link was used to estimate the continuous amount of beverage consumed. Among taxed beverages, sugar intake decreased significantly (p < 0.0001) from 28.8 g/capita/day (95% CI 27.3–30.4) pre-tax to 19.8 (95% CI 18.5–21.1) post-tax. Energy intake decreased (p < 0.0001) from 121 kcal/capita/day (95% CI 114–127) pre-tax to 82 (95% CI 76–87) post-tax. Volume intake decreased (p < 0.0001) from 315 ml/capita/day (95% CI 297–332) pre-tax to 198 (95% CI 185–211) post-tax. Among untaxed beverages, sugar intake increased (p < 0.0001) by 5.3 g/capita/day (95% CI 3.7 to 6.9), and energy intake increased (p < 0.0001) by 29 kcal/capita/day (95% CI 19 to 39). Among total beverages, sugar intake decreased significantly (p = 0.004) by 3.7 (95% CI −6.2 to −1.2) g/capita/day. Behavioral change accounted for reductions of 24% in energy, 22% in sugar, and 23% in volume, while reformulation accounted for additional reductions of 8% in energy, 9% in sugar, and 14% in volume from taxed beverages. The key limitations of this study are an inability to make causal claims due to repeat cross-sectional data collection, and that the magnitude of reduction in taxed beverage intake may not be generalizable to higher income populations.ConclusionsUsing a large sample of a high-consuming, low-income population, we found large reductions in taxed beverage intake, separating the components of behavioral change from reformulation. This reduction was partially compensated by an increase in sugar and energy from untaxed beverages. Because policies such as taxes can incentivize reformulation, our use of an up-to-date FCT that reflects a rapidly changing food supply is novel and important for evaluating policy effects on intake.

Rina Swart and co-authors use real world data to demonstrate that sugar-sweetened beverage tax was associated with reduced sugary drink intake in a low-income population within a middle-income country.  相似文献   
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Stains have been used for diagnosing infectious diseases since the late 1800s. The Gram stain remains the most commonly used stain because it detects and differentiates a wide range of pathogens. The next most commonly used diagnostic technique is acid-fast staining that is used primarily to detect Mycobacterium tuberculosis and other severe infections. Many infectious agents grow slowly on culture media or may not grow at all; stains may be the only method to detect these organisms in clinical specimens. In the hands of experienced clinical microscopists, stains provide rapid and cost-effective information for preliminary diagnosis of infectious diseases. A review of the most common staining methods used in the clinical microbiology laboratory is presented here.  相似文献   
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The patterns and correlates of obesity in China were studied in two panels of a nationwide longitudinal survey conducted in 1989 and 1991 (the China Health and Nutrition Survey). Among the Chinese adults, dietary energy and fat intakes were positively and significantly associated with the Body Mass Index (BMI). Household income and physical activity level were also significantly associated with BMI. Urban residence and higher in come were associated with lower energy intake, higher fat intake, and lower physical activity level compared to rural residence and other income categories. This paper documents an important emerging health problem: the increasing problem of obesity that has been observed in many lower-income countries during the last several decades.  相似文献   
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Objective: Dependence on motorized forms of transportation may contribute to the worldwide obesity epidemic. Shifts in transportation patterns occurring in China provide an ideal opportunity to study the association between vehicle ownership and obesity. Our objective was to determine whether motorized forms of transportation promote obesity. Research Methods and Procedures: A multistage random‐cluster sampling process was used to select households from eight provinces in China. Data were included on household vehicle ownership and individual anthropometric and sociodemographic status. Cross‐sectional data (1997) from 4741 Chinese adults aged 20 to 55 years were used to explore the association between vehicle ownership and obesity. Cohort data (1989 to 1997) from 2485 adults aged 20 to 45 years in 1989 (59% follow‐up) were used to measure the impact of vehicle acquisition on the odds of becoming obese. Results: Our main outcome measure was current obesity status and the odds of becoming obese over an 8‐year period. In 1997, 84% of adults did not own motorized transportation. However, the odds of being obese were 80% higher (p < 0.05) for men and women in households who owned a motorized vehicle compared with those who did not own a vehicle. Fourteen percent of households acquired a motorized vehicle between 1989 and 1997. Compared with those whose vehicle ownership did not change, men who acquired a vehicle experienced a 1.8‐kg greater weight gain (p < 0.05) and had 2 to 1 odds of becoming obese. Discussion: Encouraging active forms of transportation may be one way to protect against obesity.  相似文献   
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