bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonlinear Model Predictive Control for Cost Optimal Startup of Steam Power Plants (Nichtlineare modellprädiktive Regelung zum kostenoptimalen Anfahren von Dampfkraftwerken)
Authors: Franke Rüdiger , Vogelbacher Lothar 
Published: December 2006

The startup of processes is a challenging control task as a large range of operation needs to be passed and as multiple process units need to be coordinated. This makes the control problem nonlinear and multi-variable, respectively. Furthermore constraints on process variables have to be considered during a startup. Nonlinear Model Predictive Control (NMPC) is a promising concept to automate and optimize the startup of processes. Control actions are computed based on a nonlinear process model and employing a reasonable prediction horizon.
This paper states the startup optimization problem and discusses the application of online optimization in an NMPC. Appropriate numerical solution methods and their implementation in a modern control system are motivated.
The startup of a steam power plant serves as example. A process model is built using the object-oriented physical modeling technology Modelica. Based on an economic objective function the NMPC does both: online computation of optimal reference trajectories and generation of set points for an underlying base control system.
Obesity and Risk of Low Self-esteem: A Statewide Survey of Australian Children
Authors: Franklin Janet , Denyer Gareth , Steinbeck Katharine S. , Caterson Ian D. , Hill Andrew J. 
Published: December 2006

OBJECTIVE. There is variation in the psychological distress associated with child obesity. Low self-esteem, when observed, provides very little information about the nature of the distress and no indication of the proportion of obese children affected. This study used a domain approach to self-competence to evaluate self-esteem in a representative sample of Australian children.
PARTICIPANTS AND METHODS. A total of 2813 children (mean age: 11.3 years) took part in the study. They were recruited from 55 schools and were all in the last 2 years of primary school. Participants completed the Self-perception Profile for Children, a measure of body shape perception, and their height and weight were measured.
RESULTS. Obese children had significantly lower perceived athletic competence, physical appearance, and global self-worth than their normal weight peers. Obese girls scored lower in these domains than obese boys and also had reduced perceived social acceptance. Obese children were 2–4 times more likely than their normal weight peers to have low domain competence. In terms of prevalence, 1 of 3 obese boys and 2 of 3 obese girls had low appearance competence, and 10% and 20%, respectively, had low global self-worth. Body dissatisfaction mediated most of the association between BMI and low competence in boys but not in girls.
CONCLUSIONS. Obesity impacts the self-perception of children entering adolescence, especially in girls, but in selected areas of competence. Obese children are at particular risk of low perceived competence in sports, physical appearance, and peer engagement. Not all obese children are affected, although the reasons for their resilience are unclear. Quantifying risk of psychological distress alongside biomedical risk should help in arguing for more resources in child obesity treatment.
Screening Children to Identify Families at Increased Risk for Cardiovascular Disease
Authors: Reis Evelyn Cohen , Kip Kevin E. , Marroquin Oscar C. , Kiesau Marin , Hipps Lee , Peters Ronald E. , Reis Steven E. 
Published: December 2006

OBJECTIVES. Atherosclerotic cardiovascular disease is the leading cause of death in the United States. Atherosclerosis begins early in life; however, children and young and middle-aged adults are not universally screened for the presence of modifiable cardiovascular disease risk factors. The purpose of this study was to investigate whether cardiovascular disease risk-factor assessment in children can identify families who are at increased risk for cardiovascular disease.
PARTICIPANTS AND METHODS. Family Strategies Concentrating on Risk Evaluation is a community-based participatory research study designed to stratify cardiovascular disease risk in a cohort of children and their parents. Eligible families, consisting of ≥1 child and ≥1 biological parent, are recruited through community and faith-based educational and screening programs. In a single, fasted study visit, participants undergo assessment of cardiovascular disease risk factors: obesity, hypertension, dyslipidemia, and metabolic syndrome. Associations of cardiovascular disease risk factors between children and their parents were assessed.
RESULTS. Data were analyzed from 94 families: 108 parents (mean age: 38.5 ± 7.5 years), 141 children (mean age: 10.5 ± 3.4 years), and 170 child-parent pairs. Child-parent association was strong for many risk factors: BMI, waist circumference, systolic blood pressure, triglycerides, and total cholesterol. Several discrete-defined risk factors in children were found to be significant predictors of the presence of the same risk factors in their parents. Parents of children with hypertension, obesity, or hypertriglyceridemia had 15 times, 6 times, or 5 times increased odds, respectively, of having the same risk factors.
CONCLUSIONS. Identification of several clinically apparent and silent cardiovascular disease risk factors in children predicts elevated cardiovascular disease risk in their parents. Because children access primary care more frequently than adults, children can potentially serve as the index case to identify families at increased risk for cardiovascular disease.
Association of Proinflammatory Cytokine Gene Polymorphisms With Susceptibility to Otitis Media
Authors: Patel Janak A. , Nair Sangeeta , Revai Krystal , Grady James , Saeed Kokab , Matalon Reuben , Block Stan , Chonmaitree Tasnee 
Published: December 2006

OBJECTIVE. Susceptibility to otitis media results from complex interactions among genetic factors of the host, exposure to pathogens, and environmental influences. The objective of this study was to study the role of single-nucleotide polymorphisms of regulatory elements of proinflammatory cytokine genes tumor necrosis factor-α−308, interleukin-1β+3953, and interleukin-6−174, in susceptibility to recurrent otitis media in childhood.METHODS. A total of 505 children (296 otitis media susceptible, 209 nonsusceptible as control) were enrolled at 2 sites (Texas and Kentucky). DNA of the children was studied for specific single-nucleotide polymorphisms by restriction fragment length polymorphism assay and confirmed by gene sequencing.RESULTS. In the overall study group, tumor necrosis factor-α−308 and interleukin-6−174 heterozygous or homozygous polymorphisms (high cytokine-producing genotypes) were significantly associated with otitis media susceptibility. The same association was found in a match-paired subgroup of 384 subjects. In the overall study group, there was a significant step-wise increase in otitis media susceptibility with increasing number of concomitant polymorphic genotypes. Simultaneous combination of tumor necrosis factor-α−308 and interleukin-6−174 polymorphisms further increased the risk for otitis media susceptibility. These 2 polymorphic genotypes also were associated with the increased risk for tympanostomy tube placement. Children who had tumor necrosis factor-α−308 polymorphism and were breastfed for &lt;1 month or exposed to cigarette smoke were more likely to be otitis media susceptible.CONCLUSIONS. Our data suggest that tumor necrosis factor-α−308 and interleukin-6−174 polymorphisms are associated with increased risk for otitis media susceptibility and placement of tympanostomy tubes. Environmental factors such as breastfeeding may modify the risk for otitis media susceptibility in polymorphic individuals.
Pharyngitis in Low-Resources Settings: A Pragmatic Clinical Approach to Reduce Unnecessary Antibiotic Use
Authors: Smeesters Pierre Robert , Campos Dioclécio , Van Melderen Laurence , de Aguiar Eurico , Vanderpas Jean , Vergison Anne 
Published: December 2006

OBJECTIVE. Existing scoring systems for the diagnosis of group A streptococcus pharyngitis are insensitive or inapplicable in low-resources settings. Bacterial cultures and rapid tests can allow for antibiotic prescription abstention in high-income regions. These techniques are not feasible in many low-resources settings, and antibiotics often are prescribed for any pharyngitis episode. However, judicious antibiotics prescription in the community also is of concern in low-income countries. The objective of this study was to develop a clinical decision rule that allows for the reduction of empirical antibiotic therapy for children with pharyngitis in low-resources settings by identifying non–group A streptococcus pharyngitis.PATIENTS AND METHODS. We prospectively included children with pharyngitis in 3 public hospitals of Brazil during 9 months in 2004. We filled out clinical questionnaires and performed throat swabs. Bilateral χ2 (2-tailed test) and multivariate analysis were used to determine score categories. The outcome measures were sensitivity, specificity, positive likelihood ratio, and posttest probability of non–group A streptococcus infection with the clinical approach as compared with throat culture.RESULTS. A total of 163 of the 220 children had non–group A streptococcus pharyngitis (negative culture). We established a 3-questions decision rule (age and viral and bacterial signs) with 3 possible answers. The use of this score would prevent 41% to 55% of unnecessary antimicrobial prescriptions. The specificity of the score for non–group A streptococcus pharyngitis was &gt;84%.CONCLUSION. Such a clinical decision rule could be helpful to reduce significantly unnecessary antibiotic prescriptions for pharyngitis in children in low-resources settings.
Surfing for Thinness: A Pilot Study of Pro–Eating Disorder Web Site Usage in Adolescents With Eating Disorders
Authors: Wilson Jenny L. , Peebles Rebecka , Hardy Kristina K. , Litt Iris F. 
Published: December 2006

OBJECTIVE. Pro–eating disorder Web sites are communities of individuals who engage in disordered eating and use the Internet to discuss their activities. Pro-recovery sites, which are less numerous, express a recovery-oriented perspective. This pilot study investigated the awareness and usage of pro–eating disorder Web sites among adolescents with eating disorders and their parents and explored associations with health and quality of life.PATIENTS AND METHODS. This was a cross-sectional study of 698 families of patients (aged 10–22 years) diagnosed with an eating disorder at Stanford between 1997 and 2004. Anonymous surveys were mailed and offered in clinic. Survey content included questions about disease severity, health outcomes, Web site usage, and parental knowledge of eating disorder Web site usage.RESULTS. Surveys were returned by 182 individuals: 76 patients and 106 parents. Parents frequently (52.8%) were aware of pro–eating disorder sites, but an equal number did not know whether their child visited these sites, and only 27.6% had discussed them with their child. Most (62.5%) parents, however, did not know about pro-recovery sites. Forty-one percent of patients visited pro-recovery sites, 35.5% visited pro–eating disorder sites, 25.0% visited both, and 48.7% visited neither. While visiting pro–eating disorder sites, 96.0% reported learning new weight loss or purging techniques. However, 46.4% of pro-recovery site visitors also learned new techniques. Pro–eating disorder site users did not differ from nonusers in health outcomes but reported spending less time on school or schoolwork and had a longer duration of illness. Users of both pro–eating disorder and pro-recovery sites were hospitalized more than users of neither site.CONCLUSIONS. Pro–eating disorder site usage was prevalent among adolescents with eating disorders, yet parents had little knowledge of this. Although use of these sites was not associated with other health outcomes, usage may have a negative impact on quality of life and result in adolescents’ learning about and adopting disordered eating behaviors.
Marketing Fast Food: Impact of Fast Food Restaurants in Children’s Hospitals
Authors: Sahud Hannah B. , Binns Helen J. , Meadow William L. , Tanz Robert R. 
Published: December 2006

OBJECTIVES. The objectives of this study were (1) to determine fast food restaurant prevalence in hospitals with pediatric residencies and (2) to evaluate how hospital environment affects purchase and perception of fast food.
METHODS. We first surveyed pediatric residency programs regarding fast food restaurants in their hospitals to determine the prevalence of fast food restaurants in these hospitals. We then surveyed adults with children after pediatric outpatient visits at 3 hospitals: hospital M with an on-site McDonald’s restaurant, hospital R without McDonald’s on site but with McDonald’s branding, and hospital X with neither on-site McDonald’s nor branding. We sought to determine attitudes toward, consumption of, and influences on purchase of fast food and McDonald’s food.
RESULTS. Fifty-nine of 200 hospitals with pediatric residencies had fast food restaurants. A total of 386 outpatient surveys were analyzed. Fast food consumption on the survey day was most common among hospital M respondents (56%; hospital R: 29%; hospital X: 33%), as was the purchase of McDonald’s food (hospital M: 53%; hospital R: 14%; hospital X: 22%). McDonald’s accounted for 95% of fast food consumed by hospital M respondents, and 83% of them bought their food at the on-site McDonald’s. Using logistic regression analysis, hospital M respondents were 4 times more likely than respondents at the other hospitals to have purchased McDonald’s food on the survey day. Visitors to hospitals M and R were more likely than those at hospital X to believe that McDonald’s supported the hospital financially. Respondents at hospital M rated McDonald’s food healthier than did respondents at the other hospitals.
CONCLUSIONS. Fast food restaurants are fairly common in hospitals that sponsor pediatric residency programs. A McDonald’s restaurant in a children’s hospital was associated with significantly increased purchase of McDonald’s food by outpatients, belief that the McDonald’s Corporation supported the hospital financially, and higher rating of the healthiness of McDonald’s food.
Large Maternal Weight Loss From Obesity Surgery Prevents Transmission of Obesity to Children Who Were Followed for 2 to 18 Years
Authors: Kral John G. , Biron Simon , Simard Serge , Hould Frédéric-Simon , Lebel Stéfane , Marceau Simon , Marceau Picard 
Published: December 2006

OBJECTIVE. Our aim was to compare the prevalence of obesity in 172 children who were aged 2 to 18 years and born to 113 obese mothers (BMI: 31 ± 9 kg/m2) with substantial weight loss after biliopancreatic bypass surgery with 45 same-age siblings who were born before maternal surgery (mothers’ BMI: 48 ± 8 kg/m2) and with current population standards.
METHODS. In this case series, with &gt;88% follow-up in a tertiary referral center, crosssectional office chart and telephone data on childhood and adolescent weights were transformed to z scores.
RESULTS. After maternal surgery, the prevalence of obesity in the offspring decreased by 52% and severe obesity by 45.1%, with no increase in the prevalence of underweight. The z score reduction in obesity was gender specific, with boys reducing from 1.4 ± 1.3 before to 0.57 ± 1.7 after maternal surgery, corrected for birth order. The difference was not significant in girls (0.8 ± 1.3 vs 0.8 ± 1.2). Among children of both genders who were aged 6 to 18 years of age and born after maternal surgery, the prevalence of overweight was reduced to population levels.
CONCLUSIONS. Contrary to outcomes after intrauterine under- and overnutrition, the prevalence of overweight and obesity in children of mothers with large voluntary postsurgical weight loss was similar to that in the general population, with no increase in underweight. The results demonstrate the importance of potentially modifiable epigenetic factors in the cause of obesity.
Adolescents' Motivations to Abuse Prescription Medications
Authors: Boyd Carol J. , McCabe Sean Esteban , Cranford James A. , Young Amy 
Published: December 2006

OBJECTIVES. Our goals were to (1) determine adolescents' motivations (reasons) for engaging in the nonmedical (illicit) use of 4 classes of prescription medications and (2) examine whether motivations were associated with a higher risk for substance abuse problems.
RESPONDENTS. The 2005 sample (N = 1086) was derived from one ethnically diverse school district in southeastern Michigan and included 7th- through 12th-grade students.
METHODS. Data were collected by using a self-administered, Web-based survey that included questions about drug use and the motivations to engage in nonmedical use of prescription medication.
RESULTS. Twelve percent of the respondents had engaged in nonmedical use of opioid pain medications in the past year: 3% for sleeping, 2% as a sedative and/or for anxiety, and 2% as stimulants. The reasons for engaging in the nonmedical use of prescription medications varied by drug classification. For opioid analgesics, when the number of motives increased, so too did the likelihood of a positive Drug Abuse Screening Test score. For every additional motive endorsed, the Drug Abuse Screening Test increased by a factor of 1.8. Two groups of students were compared (at-risk versus self-treatment); those who endorsed multiple motivations for nonmedical use of opioids (at-risk group) were significantly more likely to have elevated Drug Abuse Screening Test scores when compared with those who were in the self-treatment group. Those in the at-risk group also were significantly more likely to engage in marijuana and alcohol use.
CONCLUSION. The findings from this exploratory study warrant additional research because several motivations for the nonmedical use of prescription medications seem associated with a greater likelihood of substance abuse problems.
Higher Self-reported Physical Activity Is Associated With Lower Systolic Blood Pressure: The Dietary Intervention Study in Childhood (DISC)
Authors: Gidding Samuel S. , Barton Bruce A. , Dorgan Joanne A. , Kimm Sue Y.S. , Kwiterovich Peter O. , Lasser Normal L. , Robson Alan M. , Stevens Victor J. , Van Horn Linda , Simons-Morton Denise G. 
Published: December 2006

OBJECTIVE. Children participating in a dietary clinical trial were studied to (1) assess physical activity patterns in boys and girls longitudinally from late childhood through puberty and (2) determine the association of level of physical activity on systolic blood pressure, low-density lipoprotein cholesterol, and BMI.PATIENTS AND METHODS. In the Dietary Intervention Study in Childhood, a randomized clinical trial of a reduced saturated fat and cholesterol diet in 8- to 10-year-olds with elevated low-density lipoprotein, a questionnaire that determined time spent in 5 intensity levels of physical activity was completed at baseline and at 1 and 3 years. An estimated-metabolic-equivalent score was calculated for weekly activity; hours per week were calculated for intense activities. We hypothesized that weekly self-reported physical activity would be associated with lower systolic blood pressure, low-density lipoprotein, and BMI over 3 years. Longitudinal data analyses were performed for each outcome (systolic blood pressure, low-density lipoprotein, and BMI) by using generalized estimating equations with estimated-metabolic-equivalent score per week as the independent variable adjusted for visit, gender, and Tanner stage (BMI was included in models for systolic blood pressure and low-density lipoprotein).RESULTS. The initial study cohort comprised 663 youths (362 boys [mean age: 9.7 years] and 301 girls [mean age: 9.0 years), of whom 623 (94%) completed the 3-year visit. For every 100 estimated-metabolic-equivalent hours of physical activity, there was a decrease of 1.15 mmHg of systolic blood pressure. There was a 1.28 mg/dL decline in low-density lipoprotein for a similar energy expenditure. For BMI, an analysis of intense physical activity showed that for every 10 hours of intense activity, there was a trend toward significance with a 0.2 kg/m2 decrease.CONCLUSIONS. Children with elevated cholesterol levels who lead a more physically active lifestyle have lower systolic blood pressure and a trend toward lower low-density lipoprotein over a 3-year interval. Long-term participation in intense physical activity may reduce BMI as well.
The Changing Risk of Infant Mortality by Gestation, Plurality, and Race: 1989–1991 Versus 1999–2001
Authors: Luke Barbara , Brown Morton B. 
Published: December 2006

OBJECTIVE. Our aim was to quantify contemporary infant mortality risks and to evaluate the change by plurality, gestation, and race during the most recent decade.PATIENTS AND METHODS. The study population included live births of 20 to 43 weeks' gestation from the 1989–1991 and 1999–2001 US Birth Cohort Linked Birth/Infant Death Data Sets, including 11317895 and 11181095 live births and 89823 and 67129 infant deaths, respectively. Adjusted odds ratios and 95% confidence intervals were calculated to evaluate the change in risk by plurality and gestation and to compare the change with that for singletons.RESULTS. Overall, the infant mortality risk decreased significantly for singletons, twins, and triplets but nonsignificantly for quadruplets and quintuplets. Compared with singletons, significantly greater reductions were experienced by twins overall and at &lt;37 weeks and triplets at &lt;29 weeks. The largest reduction was for triplets at 20 to 24 weeks and for quadruplets and quintuplets at 25 to 28 weeks. For white infants, significant reductions were achieved overall for singletons, twins, and triplets and at every gestation. For black infants, significant reductions occurred for singletons overall and at every gestation, for twins at &lt;37 weeks, and for triplets at 25 to 28 weeks. Compared with white infants, black infants had significantly lower risks before and higher risks after 33 weeks, although between 1989–1991 and 1999–2001 this survival advantage at earlier ages diminished, and the risk at later gestations increased.CONCLUSIONS. The improvements in survival were greater for multiples versus singletons and for white versus black infants. Within each plurality, at each gestation the racial disparity in mortality has widened.