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Find video protocols related to scientific articles indexed in Pubmed.
Reconstruction techniques for improving the perceptual quality of binary masked speech.
J. Acoust. Soc. Am.
PUBLISHED: 08-07-2014
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This study proposes an approach to improve the perceptual quality of speech separated by binary masking through the use of reconstruction in the time-frequency domain. Non-negative matrix factorization and sparse reconstruction approaches are investigated, both using a linear combination of basis vectors to represent a signal. In this approach, the short-time Fourier transform (STFT) of separated speech is represented as a linear combination of STFTs from a clean speech dictionary. Binary masking for separation is performed using deep neural networks or Bayesian classifiers. The perceptual evaluation of speech quality, which is a standard objective speech quality measure, is used to evaluate the performance of the proposed approach. The results show that the proposed techniques improve the perceptual quality of binary masked speech, and outperform traditional time-frequency reconstruction approaches.
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FTO genotype, dietary protein, and change in appetite: the Preventing Overweight Using Novel Dietary Strategies trial.
Am. J. Clin. Nutr.
PUBLISHED: 03-12-2014
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A common obesity-risk variant rs9939609 in the fat mass- and obesity-associated (FTO) gene was recently shown to affect appetite, and the gene is sensitive to the regulation of amino acids.
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Efficacy of a pilot Internet-based weight management program (H.E.A.L.T.H.) and longitudinal physical fitness data in Army Reserve soldiers.
J Diabetes Sci Technol
PUBLISHED: 10-27-2011
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The primary aims of this article are to describe the utilization of an Internet-based weight management Web site [Healthy Eating, Activity, and Lifestyle Training Headquarters (H.E.A.L.T.H.)] over a 12-27 month period and to describe concurrent weight and fitness changes in Army Reserve soldiers.
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Psychometric characteristics of process evaluation measures for a rural school-based childhood obesity prevention study: Louisiana Health.
Am J Health Promot
PUBLISHED: 07-05-2011
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To evaluate the implementation of intervention components of the Louisiana Health study, which was a multicomponent childhood obesity prevention program conducted in rural schools.
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Accelerometry measured ethnic differences in activity in rural adolescents.
J Phys Act Health
PUBLISHED: 03-19-2011
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To determine if there are differences in time spent in physical activity and sedentary behavior between rural African American and Caucasian children.
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Development of adherence metrics for caloric restriction interventions.
Clin Trials
PUBLISHED: 03-08-2011
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objective measures are needed to quantify dietary adherence during caloric restriction (CR) while participants are freeliving. One method to monitor adherence is to compare observed weight loss to the expected weight loss during a prescribed level of CR. Normograms (graphs) of expected weight loss can be created from mathematical modeling of weight change to a given level of CR, conditional on the individuals set of baseline characteristics. These normograms can then be used by counselors to help the participant adhere to their caloric target.
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H.E.A.L.T.H.: efficacy of an internet/population-based behavioral weight management program for the U.S. Army.
J Diabetes Sci Technol
PUBLISHED: 02-10-2011
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A significant number of soldiers exceed the maximum allowable weight standards or have body weights approaching the maximum allowable weight standards. This mandates development of scalable approaches to improve compliance with military weight standards.
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The CALERIE Study: design and methods of an innovative 25% caloric restriction intervention.
Contemp Clin Trials
PUBLISHED: 01-19-2011
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Animal studies have shown that life span is extended by caloric restriction (CR). This manuscript describes the design and methodology of an innovative CR intervention, which is the treatment arm of the CALERIE Study. This study is a multi-center, randomized controlled trial examining the effects of 2 years of CR on biomarkers of longevity among non-obese (BMI ? 22 kg/m(2) and <28 kg/m(2)) adults. CALERIE is the first investigation of the effects of long-term CR on the aging process in non-obese humans. 220 healthy volunteers across 3 sites were recruited beginning in May 2007. Participants were randomized in a 2:1 ratio between the CR or control group (i.e., ad libitum diet). An intensive intervention was designed to assist participants in adhering to the 25% CR prescription for a two-year duration. The intervention was designed to optimize the likelihood that 25% CR would be achieved through a variety of nutritional and behavioral strategies, several of which are innovative methods for achieving CR. The intervention includes the following components: an intensive, "mixed" format schedule of group/individual sessions, meal provision phase with exposure to various diets, Personal Digital Assistants to monitor caloric intake, unique portion estimation training, tailored treatment using a computer tracking system, toolbox strategies and algorithms, as well as comprehensive coverage of nutrition and behavioral topics in order to assist participants in meeting their CR goal. This manuscript provides an overview of the CR intensive intervention and may be of assistance for other researchers and clinicians in designing future trials.
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Body image changes associated with participation in an intensive lifestyle weight loss intervention.
Obesity (Silver Spring)
PUBLISHED: 12-09-2010
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The primary aim of this study was to test for changes in body image in men and women enrolled in the Look AHEAD trial. Look AHEAD (Action for Health in Diabetes) is a multicenter, randomized controlled trial designed to test whether intentional weight loss reduces cardiovascular morbidity and mortality in overweight individuals with type 2 diabetes. Participants included 157 adults at one site (Pennington Biomedical Research Center (PBRC), Baton Rouge, LA) of the Look AHEAD study. At baseline, the mean BMI of the female participants was 36.4, and the mean BMI for males was 33.5. Following baseline assessment, participants were randomly assigned to the intensive lifestyle intervention (ILI, n = 81) or diabetes support and education (DSE, n = 76). The body morph assessment version 2.0 (BMA 2.0) was used to assess estimates of perceived current body size, ideal body size, acceptable body size, and body image dissatisfaction at baseline and 1 year. Over the 1 year, participants in the ILI group had significantly greater reductions in weight (10.1% for men and 8.9% for women) than those in the DSE group (+ 0.8% for men and -0.2%, for women). Perceived current body size was reduced significantly more in both men and women in the ILI group, relative to DSE. There were also significantly greater reductions in body image dissatisfaction in the ILI group, relative to the DSE group for men and women. The results of this study indicate that body image dissatisfaction improved following participation in an intensive behavioral weight loss program.
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Longitudinal study of body weight changes in children: who is gaining and who is losing weight.
Obesity (Silver Spring)
PUBLISHED: 09-30-2010
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Cross-sectional studies have reported significant temporal increases in prevalence of childhood obesity in both genders and various racial groups, but recently the rise has subsided. Childhood obesity prevention trials suggest that, on average, overweight/obese children lose body weight and nonoverweight children gain weight. This investigation tested the hypothesis that overweight children lose body weight/fat and nonoverweight children gain body weight/fat using a longitudinal research design that did not include an obesity prevention program. The participants were 451 children in 4th to 6th grades at baseline. Height, weight, and body fat were measured at month 0 and month 28. Each childs BMI percentile score was calculated specific for their age, gender and height. Higher BMI percentile scores and percent body fat at baseline were associated with larger decreases in BMI and percent body fat after 28 months. The BMI percentile mean for African-American girls increased whereas BMI percentile means for white boys and girls and African-American boys were stable over the 28-month study period. Estimates of obesity and overweight prevalence were stable because incidence and remission were similar. These findings support the hypothesis that overweight children tend to lose body weight and nonoverweight children tend to gain body weight.
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Children in school cafeterias select foods containing more saturated fat and energy than the Institute of Medicine recommendations.
J. Nutr.
PUBLISHED: 07-28-2010
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In this study, we examined if childrens food selection met the School Meals Initiative (SMI) standards and the recently released Institute of Medicine (IOM) recommendations. Mean food selection, plate waste, and food intake were also examined. Food intake of 2049 4th-6th grade students was measured objectively at lunch over 3 d with digital photography in 33 schools. The percent of children whose food selection met the SMI standards and IOM recommendations for energy (kJ), fat and saturated fat, calcium, iron, and vitamin A and C were calculated. The SMI standards provide lower limits for most nutrients; the IOM provides a range of values, including an upper limit for energy. Seventy-seven percent of childrens energy selection met the SMI lower limit, but only 16% of children met the IOMs recommended range and 74% of children exceeded the upper limit. More than 70% of children exceeded the SMI and IOMs saturated fat recommendations. Children selected (mean +/- SD) 3168 +/- 621 kJ, discarded 882 +/- 581 kJ, and consumed 2286 +/- 716 kJ. Children were less likely to discard fat than carbohydrate, resulting in proportionally more fat being consumed. Most children met SMI and IOM recommendations for protein, calcium, iron, and vitamin A. With few exceptions, energy selection was similar among groups of children, but plate waste differed (P < 0.001), resulting in greater energy intake among boys compared with girls, Caucasians compared with African Americans, and heavier compared with lighter children. Childrens selection was high in saturated fat and, based on IOM criteria, included excess energy.
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Development of an internet-based obesity prevention program for children.
J Diabetes Sci Technol
PUBLISHED: 06-02-2010
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Childhood obesity is a growing problem, particularly in rural, Louisiana school children. Traditionally, school-based obesity prevention programs have used a primary prevention approach. Finding methods to deliver secondary prevention programs to large numbers of students without singling out overweight students has been a challenge. An innovative approach to achieving this goal is through use of an Internet intervention targeted toward a students weight status. This article describes the Louisiana (LA) Health Internet intervention, including the student Web site, the Internet counselor Web site, and the Internet counseling process.
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An environmental intervention to prevent excess weight gain in African-American students: a pilot study.
Am J Health Promot
PUBLISHED: 05-15-2010
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To examine the influence of an environmental intervention to prevent excess weight gain in African-American children.
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Effects of stevia, aspartame, and sucrose on food intake, satiety, and postprandial glucose and insulin levels.
Appetite
PUBLISHED: 03-10-2010
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Consumption of sugar-sweetened beverages may be one of the dietary causes of metabolic disorders, such as obesity. Therefore, substituting sugar with low calorie sweeteners may be an efficacious weight management strategy. We tested the effect of preloads containing stevia, aspartame, or sucrose on food intake, satiety, and postprandial glucose and insulin levels. Design: 19 healthy lean (BMI=20.0-24.9) and 12 obese (BMI=30.0-39.9) individuals 18-50 years old completed three separate food test days during which they received preloads containing stevia (290kcal), aspartame (290kcal), or sucrose (493kcal) before the lunch and dinner meal. The preload order was balanced, and food intake (kcal) was directly calculated. Hunger and satiety levels were reported before and after meals, and every hour throughout the afternoon. Participants provided blood samples immediately before and 20min after the lunch preload. Despite the caloric difference in preloads (290kcal vs. 493kcal), participants did not compensate by eating more at their lunch and dinner meals when they consumed stevia and aspartame versus sucrose in preloads (mean differences in food intake over entire day between sucrose and stevia=301kcal, p<.01; aspartame=330kcal, p<.01). Self-reported hunger and satiety levels did not differ by condition. Stevia preloads significantly reduced postprandial glucose levels compared to sucrose preloads (p<.01), and postprandial insulin levels compared to both aspartame and sucrose preloads (p<.05). When consuming stevia and aspartame preloads, participants did not compensate by eating more at either their lunch or dinner meal and reported similar levels of satiety compared to when they consumed the higher calorie sucrose preload.
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Early behavioral adherence predicts short and long-term weight loss in the POUNDS LOST study.
J Behav Med
PUBLISHED: 02-11-2010
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The primary aim of this study was to test the association of early (first 6 months) adherence related to diet, self-monitoring, and attendance with changes in adiposity and cardiovascular risk factors. This study used data from the 24-month POUNDS LOST trial that tested the efficacy of four dietary macronutrient compositions for short-and long-term weight loss. A computer tracking system was used to record data on eight indicator variables related to adherence. Using canonical correlations at the 6 and 24 month measurement periods, early behavioral adherence was associated with changes in percent weight loss and waist circumference at 6 months (R = 0.52) and 24 months (R = 0.37), but was not associated with cardiovascular disease risk factor levels. Early dietary adherence was associated with changes in insulin at 6 months (R = 0.19), but not at 24 months (R = 0.08, ns). Early dietary adherence was not associated with changes in adiposity.
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The effect of caloric restriction interventions on growth hormone secretion in nonobese men and women.
Aging Cell
PUBLISHED: 10-30-2009
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Lifespan in rodents is prolonged by caloric restriction (CR) and by mutations affecting the somatotropic axis. It is not known if CR can alter the age-associated decline in growth hormone (GH), insulin-like growth factor (IGF)-1 and GH secretion. To evaluate the effect of CR on GH secretory dynamics; forty-three young (36.8 +/- 1.0 years), overweight (BMI 27.8 +/- 0.7) men (n = 20) and women (n = 23) were randomized into four groups; control = 100% of energy requirements; CR = 25% caloric restriction; CR + EX = 12.5% CR + 12.5% increase in energy expenditure by structured exercise; LCD = low calorie diet until 15% weight reduction followed by weight maintenance. At baseline and after 6 months, body composition (DXA), abdominal visceral fat (CT) 11 h GH secretion (blood sampling every 10 min for 11 h; 21:00-08:00 hours) and deconvolution analysis were measured. After 6 months, weight (control: -1 +/- 1%, CR: -10 +/- 1%, CR + EX: -10 +/- 1%, LCD: -14 +/- 1%), fat mass (control: -2 +/- 3%, CR: -24 +/- 3%, CR + EX: -25 +/- 3%, LCD: -31 +/- 2%) and visceral fat (control: -2 +/- 4%, CR: -28 +/- 4%, CR + EX: -27 +/- 3%, LCD: -36 +/- 2%) were significantly (P < 0.001) reduced in the three intervention groups compared to control. Mean 11 h GH concentrations were not changed in CR or control but increased in CR + EX (P < 0.0001) and LCD (P < 0.0001) because of increased secretory burst mass (CR + EX: 34 +/- 13%, LCD: 27 +/- 22%, P < 0.05) and amplitude (CR + EX: 34 +/- 14%, LCD: 30 +/- 20%, P < 0.05) but not to changes in secretory burst frequency or GH half-life. Fasting ghrelin was significantly increased from baseline in all three intervention groups; however, total IGF-1 concentrations were increased only in CR + EX (10 +/- 7%, P < 0.05) and LCD (19 +/- 4%, P < 0.001). A 25% CR diet for 6 months does not change GH, GH secretion or IGF-1 in nonobese men and women.
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Increased obesity in children living in rural communities of Louisiana.
Int J Pediatr Obes
PUBLISHED: 10-15-2009
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Rates of obesity among children have been rising in recent years. Information on the prevalence of obesity in children living in rural communities is needed. We report the prevalence of overweight and obesity in children enrolled in grades 4 to 6 who live in rural areas of Louisiana, USA.
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Caloric restriction alone and with exercise improves CVD risk in healthy non-obese individuals.
Atherosclerosis
PUBLISHED: 09-10-2009
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Calorie restriction (CR) delays the development of age-associated disease and increases lifespan in rodents, but the effects in humans remain uncertain.
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Caterpillars evolved from onychophorans by hybridogenesis.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-28-2009
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I reject the Darwinian assumption that larvae and their adults evolved from a single common ancestor. Rather I posit that, in animals that metamorphose, the basic types of larvae originated as adults of different lineages, i.e., larvae were transferred when, through hybridization, their genomes were acquired by distantly related animals. "Caterpillars," the name for eruciforms with thoracic and abdominal legs, are larvae of lepidopterans, hymenopterans, and mecopterans (scorpionflies). Grubs and maggots, including the larvae of beetles, bees, and flies, evolved from caterpillars by loss of legs. Caterpillar larval organs are dismantled and reconstructed in the pupal phase. Such indirect developmental patterns (metamorphoses) did not originate solely by accumulation of random mutations followed by natural selection; rather they are fully consistent with my concept of evolution by hybridogenesis. Members of the phylum Onychophora (velvet worms) are proposed as the evolutionary source of caterpillars and their grub or maggot descendants. I present a molecular biological research proposal to test my thesis. By my hypothesis 2 recognizable sets of genes are detectable in the genomes of all insects with caterpillar grub- or maggot-like larvae: (i) onychophoran genes that code for proteins determining larval morphology/physiology and (ii) sequentially expressed insect genes that code for adult proteins. The genomes of insects and other animals that, by contrast, entirely lack larvae comprise recognizable sets of genes from single animal common ancestors.
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Adherence is a multi-dimensional construct in the POUNDS LOST trial.
J Behav Med
PUBLISHED: 04-16-2009
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Research on the conceptualization of adherence to treatment has not addressed a key question: Is adherence best defined as being a uni-dimensional or multi-dimensional behavioral construct? The primary aim of this study was to test which of these conceptual models best described adherence to a weight management program. This ancillary study was conducted as a part of the POUNDS LOST trial that tested the efficacy of four dietary macronutrient compositions for promoting weight loss. A sample of 811 overweight/obese adults was recruited across two clinical sites, and each participant was randomly assigned to one of four macronutrient prescriptions: (1) Low fat (20% of energy), average protein (15% of energy); (2) High fat (40%), average protein (15%); (3) Low fat (20%), high protein (25%); (4) High fat (40%), high protein (25%). Throughout the first 6 months of the study, a computer tracking system collected data on eight indicators of adherence. Computer tracking data from the initial 6 months of the intervention were analyzed using exploratory and confirmatory analyses. Two factors (accounting for 66% of the variance) were identified and confirmed: (1) behavioral adherence and (2) dietary adherence. Behavioral adherence did not differ across the four interventions, but prescription of a high fat diet (vs. a low fat diet) was found to be associated with higher levels of dietary adherence. The findings of this study indicated that adherence to a weight management program was best conceptualized as being multi-dimensional, with two dimensions: behavioral and dietary adherence.
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Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates.
N. Engl. J. Med.
PUBLISHED: 02-28-2009
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The possible advantage for weight loss of a diet that emphasizes protein, fat, or carbohydrates has not been established, and there are few studies that extend beyond 1 year.
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Military services fitness database: development of a computerized physical fitness and weight management database for the U.S. Army.
Mil Med
PUBLISHED: 02-17-2009
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The Department of Defense (DoD) has mandated development of a system to collect and manage data on the weight, percent body fat (%BF), and fitness of all military personnel. This project aimed to (1) develop a computerized weight and fitness database to track individuals and Army units over time allowing cross-sectional and longitudinal evaluations and (2) test the computerized system for feasibility and integrity of data collection over several years of usage. The computer application, the Military Services Fitness Database (MSFD), was designed for (1) storage and tracking of data related to height, weight, %BF for the Army Weight Control Program (AWCP) and Army Physical Fitness Test (APFT) scores and (2) generation of reports using these data. A 2.5-year pilot test of the MSFD indicated that it monitors population and individual trends of changing body weight, %BF, and fitness in a military population.
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Metabolic and behavioral compensations in response to caloric restriction: implications for the maintenance of weight loss.
PLoS ONE
PUBLISHED: 02-09-2009
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Metabolic and behavioral adaptations to caloric restriction (CR) in free-living conditions have not yet been objectively measured.
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Impact of a weight management program on health-related quality of life in overweight adults with type 2 diabetes.
Arch. Intern. Med.
PUBLISHED: 01-28-2009
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Inconsistent findings have been reported regarding improved health-related quality of life (HRQOL) after weight loss. We tested the efficacy of a weight management program for improving HRQOL in overweight or obese adults diagnosed as having type 2 diabetes mellitus.
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The development of the Body Morph Assessment version 2.0 (BMA 2.0): tests of reliability and validity.
Body Image
PUBLISHED: 01-22-2009
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This study tested the psychometric characteristics of the Body Morph Assessment version 2.0 (BMA 2.0). A sample of 563 adults composed of four groups classified by gender and ethnicity (Caucasian men and women and African-American men and women) were studied. Support for the internal consistency and test-retest reliability of the BMA 2.0 was found for both men and women. A study of convergent validity was conducted. The BMA 2.0 was found to have adequate reliability and validity. Norms were established for the BMA 2.0 estimates of current body size (CBS), ideal body size (IBS), and acceptable body size (ABS) for Caucasian and African-American men and women. In summary, the BMA 2.0 is a reliable and valid computerized measure of CBS, IBS, ABS, the CBS-IBS discrepancy (body dissatisfaction), and provides an estimate of over/underestimation of body size as compared to individuals of the same sex and body mass index.
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Modification of the school cafeteria environment can impact childhood nutrition. Results from the Wise Mind and LA Health studies.
Appetite
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Recent changes in nutrition standards for the National School Lunch and School Breakfast Programs assume that modification of the nutritional serving practices of school cafeterias will result in improved childhood nutrition in the school environment. The primary aim of this paper is to summarize the findings from two recent cluster randomized controlled trials (Wise Mind and LA Health) that tested the hypothesis that modification of school cafeteria environments, including changes in nutrition standards, would yield beneficial changes in childhood nutrition and healthy eating in the school lunch environment. A secondary aim was to investigate the association of participant characteristics and changes in nutrition and healthy eating. A third aim was to investigate the relationships between the food intake of children and: (1) foods selected by the children and (2) food that was uneaten during the lunch meal (plate waste). The studies used similar approaches for modifying the school cafeteria environment and both studies used the digital photography method to measure changes in food intake, food selection, and plate waste. Both studies reported significant improvements in childhood nutrition, and the LA Health study reported improved healthy eating, following introduction of the cafeteria modification program in comparison to baseline and/or control arms. These studies confirm the hypothesis that interventions that modify the school cafeteria environment can beneficially impact childhood nutrition.
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Pretreatment, psychological, and behavioral predictors of weight outcomes among lifestyle intervention participants in the Diabetes Prevention Program (DPP).
Diabetes Care
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To identify the most important pretreatment characteristics and changes in psychological and behavioral factors that predict weight outcomes in the Diabetes Prevention Program (DPP).
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Use of a computerized tracking system to monitor and provide feedback on dietary goals for calorie-restricted diets: the POUNDS LOST study.
J Diabetes Sci Technol
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The use of self-monitoring as a tool to facilitate behavioral modification is common in many lifestyle-based weight loss interventions. Electronic tracking programs, including computer-based systems and smart phone applications, have been developed to allow individuals to self-monitor their behavior digitally. These programs offer an advantage over traditional self-report modalities in that they can provide users with direct feedback about dietary and/or physical activity adherence levels and thereby assist them in real-time decision making. This article describes the use of an Internet-based computerized tracking system (CTS) that was developed specifically for the POUNDS LOST study, a 2-year randomized controlled trial designed to test the efficacy of four macronutrient diets for weight and fat reduction in healthy, overweight men and women (body mass index range = 25.0-39.9 kg/m(2)). The CTS served many functions in this study, including data collection, dietary and exercise assessment and feedback, messaging system, and report generation. Across all groups, participants with high usage of the CTS during the initial 8 weeks lost greater amounts of weight than participants with low usage (8.7% versus 5.5% of initial body weight, respectively; p < .001) at week 32. Rates of CTS utilization were highest during the first year of this 2-year intervention, and utilization of the CTS declined steadily over time. The unique features of the CTS combined with technological developments, such as smart phone applications, offer significant potential to improve the users self-monitoring experience and adherence to health promotion programs designed specifically for individuals with obesity and type 2 diabetes.
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Coping with brief periods of food restriction: mindfulness matters.
Front Aging Neurosci
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The obesity epidemic had spawned considerable interest in understanding peoples responses to palatable food cues that are plentiful in obesogenic environments. In this paper we examine how trait mindfulness of older, obese adults may moderate brain networks that arise from exposure to such cues. Nineteen older, obese adults came to our laboratory on two different occasions. Both times they ate a controlled breakfast meal and then were restricted from eating for 2.5 h. After this brief period of food restriction, they had an fMRI scan in which they were exposed to food cues and then underwent a 5 min recovery period to evaluate brain networks at rest. On one day they consumed a BOOST® liquid meal prior to scanning, whereas on the other day they only consumed water (NO BOOST® condition). We found that adults high in trait mindfulness were able to return to their default mode network (DMN), as indicated by greater global efficiency in the precuneus, during the post-exposure rest period. This effect was stronger for the BOOST® than NO BOOST® treatment condition. Older adults low in trait mindfulness did not exhibit this pattern in the DMN. In fact, the brain networks of those low on the MAAS suggests that they continued to be pre-occupied with the elaboration of food cues even after cue exposure had ended. Further work is needed to examine whether mindfulness-based therapies alter brain networks to food cues and whether these changes are related to eating behavior.
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Effect of diet composition and weight loss on resting energy expenditure in the POUNDS LOST study.
Obesity (Silver Spring)
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Weight loss reduces energy expenditure, but it is unclear whether dietary macronutrient composition affects this reduction. We hypothesized that energy expenditure might be modulated by macronutrient composition of the diet. The Prevention of Obesity Using Novel Dietary Strategies (POUNDS) LOST study, a prospective, randomized controlled trial in 811 overweight/obese people who were randomized in a 2 × 2 design to diets containing 20en% or 40en% fat and 15en% or 25en% protein (diets with 65%, 55%, 45%, and 35% carbohydrate) provided the data to test this hypothesis. Resting energy expenditure (REE) was measured at baseline, 6, and 24 months using a ventilated hood. REE declined at 6 months by 99.5 ± 8.0 kcal/day in men and 55.2 ± 10.6 kcal/day in women during the first 6 months. This decline was related to the weight loss, and there was no difference between the diets. REE had returned to baseline by 24 months, but body weight was still 60% below baseline. Measured REE at 6 months was significantly lower than the predicted (-18.2 ± 6.7 kcal/day) and was the result of significant reductions from baseline in the low-fat diets (65% or 55% carbohydrate), but not in the high fat diet groups. By 24 months the difference had reversed with measured REE being slightly but significantly higher than predicted (21.8 ± 10.1 kcal/day). In conclusion, we found that REE fell significantly after weight loss but was not related to diet composition. Adaptive thermogenesis was evident at 6 months, but not at 24 months.
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Adiposity and physical activity are not related to academic achievement in school-aged children.
J Dev Behav Pediatr
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To investigate the hypotheses that in elementary school students: (1) adiposity and academic achievement are negatively correlated and (2) physical activity and academic achievement are positively correlated.
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Effect of an environmental school-based obesity prevention program on changes in body fat and body weight: a randomized trial.
Obesity (Silver Spring)
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This study tested the efficacy of two school-based programs for prevention of body weight/fat gain in comparison to a control group, in all participants and in overweight children. The Louisiana (LA) Health study utilized a longitudinal, cluster randomized three-arm controlled design, with 28 months of follow-up. Children (N = 2,060; mean age = 10.5 years, SD = 1.2) from rural communities in grades 4-6 participated in the study. Seventeen school clusters (mean = 123 children/cluster) were randomly assigned to one of three prevention arms: (i) primary prevention (PP), an environmental modification (EM) program, (ii) primary + secondary prevention (PP+SP), the environmental program with an added classroom and internet education component, or (iii) control (C). Primary outcomes were changes in percent body fat and BMI z scores. Secondary outcomes were changes in behaviors related to energy balance. Comparisons of PP, PP+SP, and C on changes in body fat and BMI z scores found no differences. PP and PP+SP study arms were combined to create an EM arm. Relative to C, EM decreased body fat for boys (-1.7 ± 0.38% vs. -0.14 ± 0.69%) and attenuated fat gain for girls (2.9 ± 0.22% vs. 3.93 ± 0.37%), but standardized effect sizes were relatively small (<0.30). In conclusion, this school-based EM programs had modest beneficial effects on changes in percent body fat. Addition of a classroom/internet program to the environmental program did not enhance weight/fat gain prevention, but did impact physical activity and social support in overweight children.
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Power of food moderates food craving, perceived control, and brain networks following a short-term post-absorptive state in older adults.
Appetite
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The Power of Food Scale (PFS) is a new measure that assesses the drive to consume highly palatable food in an obesogenic food environment. The data reported in this investigation evaluate whether the PFS moderates state cravings, control beliefs, and brain networks of older, obese adults following either a short-term post-absorptive state, in which participants were only allowed to consume water, or a short-term energy surfeit treatment condition, in which they consumed BOOST®. We found that the short-term post-absorptive condition, in which participants consumed water only, was associated with increases in state cravings for desired food, a reduction in participants confidence related to the control of eating behavior, and shifts in brain networks that parallel what is observed with other addictive behaviors. Furthermore, individuals who scored high on the PFS were at an increased risk for experiencing these effects. Future research is needed to examine the eating behavior of persons who score high on the PFS and to develop interventions that directly target food cravings.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.