Assessing overweight, obesity, diet, and physical activity in college students

The authors surveyed 738 college students aged 18 to 27 years to assess overweight, obesity, dietary habits, and physical activity. They used BMI (body mass index) > or = 25 kg/m2 or BMI > or = 85th percentile and BMI > or = 30 kg/m2 or BMI > or = 95th percentile to estimate overweight and obesity in those aged < or = 19 years. To define overweight and obesity in those > or = 20 years, they used BMI > or = 25 kg/m2 and > or = 30 kg/m2. They found overweight rates of 21.6% using BMI directly and 16.2% using BMI percentile and obesity rates of 4.9% using BMI directly and 4.2% using BMI percentile. More than 69% of the participants reported < 5 servings of fruits and vegetables per day and more than 67% reported < 20 g of fiber per day; participants reported physical activity on fewer than 3 d/wk. Most college students are not meeting dietary and physical activity guidelines, suggesting the need for prevention interventions and increased understanding of overweight in college students.     

The hunt for a cure for Parkinson's disease

Several exciting new scientific advances have been made in the past decade toward both understanding the causes of and finding a cure for Parkinson's disease. Heartened by an acceleration in research findings in the past several years, the government has recently called for an infusion of funds from both the National Institutes of Health and private foundations into this burgeoning area of biomedical research. Most currently available conventional treatments for the disease only temporarily delay symptom presentation while doing nothing to halt disease progression. However, the rapidly accelerating pace of research in this field has left researchers hopeful that Parkinson's will be the first major age-related neurodegenerative disease for which we have a viable cure. In this article, advances in various areas of Parkinson's disease research are reviewed.     

Adaptive threshold method for peak detection of surface electromyography signal from around shoulder muscles

This paper illustrates the accurate identification of the surface electromyography signal obtained from the shoulder muscles (Teres, Trapezius and Pectoralis) of amputee subjects with three different arm motions (elevation, protraction and retraction). During the acquisition of the signal, a variety of variations (amplitude, frequency and noise) were introduced into the acquired signal which will misguide in the prediction of motion of the shoulder. Therefore, a novel approach has been aimed to adaptively adjust the threshold of Teager energy operator in order to filter the unwanted peaks in the pre-processing stage of the surface electromyography (SEMG) signal. Results show that the proposed approach is accurate and effective in the analysis of biomedical signal where peaks are important to detect without the knowledge of the shape of the waveform. As clinical research continues, these algorithms helps us to process SEMG signal and the identified signal would be used to design more accurate and efficient controllers for the upper-limb amputee.     

Scheduling arc shut downs in a network to maximize flow over time with a bounded number of jobs per time period

We study the problem of scheduling maintenance on arcs of a capacitated network so as to maximize the total flow from a source node to a sink node over a set of time periods. Maintenance on an arc shuts down the arc for the duration of the period in which its maintenance is scheduled, making its capacity zero for that period. A set of arcs is designated to have maintenance during the planning period, which will require each to be shut down for exactly one time period. In general this problem is known to be NP-hard, and several special instance classes have been studied. Here we propose an additional constraint which limits the number of maintenance jobs per time period, and we study the impact of this on the complexity.     

Environmental sampling with a concomitant variable: a comparison between ranked set sampling and stratified simple random sampling

In many environmental sampling situations, the variable of interest is either not easily observable or is too expensive to observe. Under such circumstances, the need arises to observe another variable, related to the variable of interest, so as to estimate the population parameters of interest. We study the performance of two different sampling procedures, i.e. ranked set sampling and stratified simple random sampling, when both stratification and ranking are accomplished on the basis of such a concomitant variable. The relative precision of the two methods is obtained and expressed as a function of population variance, between-stratum and between-rank variation, and the correlation coefficient between the variable of interest and the concomitant variable. The relative precision is computed for several important families of distributions that occur frequently in environmental and ecological work. Under equal allocation of sampling units, stratified simple random sampling is found to perform better than ranked set sampling, when the costs incurred to obtain sample measurements are ignored. When optimum allocation is considered for both methods, ranked set sampling performs better than stratified simple random sampling, when the concomitant variable is not highly correlated with the variable of interest. Furthermore, when the costs of sampling and the costs of measurement are incorporated into the assessment of the relative precision, the ranked set sampling is seen to be more efficient than stratified simple random sampling, particularly when the cost of stratification is high compared with that of ranking. This is generally the case in practice.     

Rhythms of moving in and between digital media: a study on video diaries of young people with physical disabilities

This article develops a new framework for analysing digital media use and access by drawing on the concepts of ‘rhythm’ and ‘wayfaring.’ It unravels how young people with physical disabilities move in and between digital media devices, online sites and activities in an embodied and rhythmic way that happens at a fast or slow pace. The framework is used to analyse the video diaries of three male secondary school students with physical disabilities on their use of digital media at home. We propose methodological advances in studying digital media use as dynamic movement and provide alternative insights on digital inequalities.     

Statistical issues in studying the relative importance of body mass index,waist circumference,waist hip ratio and waist stature ratio to predict type 2 diabetes

Systematic and appropriate statistical analysis is needed to examine the relative performance of anthropometrical indices, viz. body mass index (BMI), waist circumference (WC), waist hip ratio (WHR) and waist stature ratio (WSR) for predicting type 2 diabetes. Using information on socio-demographic, anthropometric and biochemical variables from 2148 males, we examined collinearity and non-linearity among the predictors before studying the association between anthropometric indices and type 2 diabetes. The variable involving in collinearity was removed from further analysis, and the relative importance of BMI, WC and WHR was examined by logistic regression analysis. To avoid non-interpretable odds ratios (ORs), cut point theory is used. Optimal cut points are derived and tested for significance. Multivariable fractional polynomial (MFP) algorithm is applied to reconcile non-linearity. As expected, WSR and WC were collinear with WHR and BMI. Since WSR was jointly as well as independently collinear, it was dropped from further analysis. The OR for WHR could not be interpreted meaningfully. Cut point theory was adopted. Deciles emerged as the optimal cut point. MFP recognized non-linearity effects on the outcome. Multicollinearity among the anthropometric indices was examined. Optimal cut points were identified and used to study the relative ORs. On the basis of the results of analysis, MFP is recommended to accommodate non-linearity among the predictors. WHR is relatively more important and significant than WC and BMI.     

Leptin as a marker of body fat and hyperinsulinemia in college students

Little is known about obesity and insulin resistance in college students. Leptin is a hormone secreted by fat cells and has been shown to strongly correlate with both obesity and insulin resistance in children and adults. We investigated associations of leptin with insulin secretion and action in 119 normal-weight students aged 18-24 years. Leptin was strongly correlated with total fat mass (r = .67, p <.001), percentage body fat (r= .81, p < .001), and to a lesser degree Body Mass Index, or BMI, (r = .23, p < .02). Leptin was associated with fasting insulin (beta+/-SE = 0.30+/-0.06, p < .001) and insulin resistance (beta+/-SE = 0.41+/-0.20, p < .001) independent of total fat, gender, and age, suggesting other mechanisms of leptin and insulin regulation besides obesity. Leptin resistance is present even among young and normal-weight college students. Leptin, even more so than BMI, is an important marker of adiposity and hyperinsulinemia in normal-weight college students and may potentially be used to predict type 2 diabetes.     

Gambling Control Self-efficacy as a Mediator of the Effects of Low Emotional Intelligence on Problem Gambling

This study investigated whether lower emotional intelligence would be related to less self-efficacy to control gambling and more problem gambling and whether gambling self-efficacy would mediate the relationship between emotional intelligence and problem gambling. A total of 117 participants, including 49 women and 68 men, with an average age of 39.93 (SD = 13.87), completed an emotional intelligence inventory, a gambling control self-efficacy scale, and a measure of problem gambling. Lower emotional intelligence was related to lower gambling self-efficacy and more problem gambling. Gambling control self-efficacy partially mediated the relationship between emotional intelligence and problem gambling.