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High-level cognitive function is essential for academic performance in adolescents. While obtaining sufficient sleep duration has been shown to support cognitive function less is known about the role of sleep regularity in cognitive function. We investigated how sleep regularity relates to self-report cognitive function in 179 Year 7 students (M±SD=12.81±0.41 years, 56% females) in Australia. Sleep/wake timing was measured via wrist actigraphy and daily sleep diaries over two-school-weeks. Sleep regularity was measured using the Sleep Regularity Index (SRI) calculated via actigraphy measured sleep (SRI range = 58-95). Self-report cognitive function was measured using the PROMIS Paediatric Cognitive Function questionnaire, which requires participants to self-report cognitive performance over the last four-weeks. Academic skills were measured using two-subtests (reading comprehension and numerical operations) from the Weschler Individual Achievement Test – Third Edition (WIAT-III). We found that adolescents with more regular sleep self-reported better subjective cognitive function (β = .39, p = .001), even when controlling for age, sex, circadian phase assessed using DLMO, and total sleep time. In contrast, average total sleep time (range = 5.78-11.30 hours) alone was not associated with subjective cognitive function (β = .06, p = .99). Higher self-reported cognitive function was also associated with improved reading and numerical ability on the WIAT-III (β = .42, p =.04; β = .37, p =.02, respectively). The SRI did not predict performance on the WIAT (p >.05). Our findings suggest regular sleep may be important in supporting optimal cognitive functioning. These results have important implications for learning adolescence.

Semi-active anti-roll systems, with a high and low roll stiffness, or, since cornering is typically a transient event, damping setting have the capacity to improve heavy vehicle stability while having very low power consumption. If a vehicle is travelling around a right-hand bend and a low roll damping setting is selected, the vehicle will roll outwards. If a high damping setting is then selected, the outward roll will be locked-in. When the vehicle enters a left-hand bend, the inward roll becomes locked-in. This has the potential to increase critical lateral acceleration by up to 12.5% if the vehicle's future course can be predicted accurately (e.g. with a Global Positioning System). However, if the vehicle does not follow the expected path, the critical lateral acceleration may be degraded. Exploiting the delay between a steer angle being applied and the lateral acceleration developing could avoid this problem. However, the benefits from such a system are considerably lower, up to a 2.4% improvement in critical lateral acceleration. Hence, a 'modal control strategy' is developed aimed at providing high levels of benefit while being robust to deviations from the expected path. The modal strategy is able to provide benefits of up to 11%, while being robust to most deviations.

The use of anti-roll bars to provide additional roll stiffness and therefore to reduce the trade-off between ride and rollover performance has previously been studied. However, little work has been carried out to investigate the benefits of a switchable roll stiffness. Such a semi-active anti-roll system has the ability to have a low roll stiffness during straight-ahead driving for improved ride performance and high roll stiffness during cornering for improved roll performance. Modelling of such a system is conducted and the model is validated against a semi-active anti-roll system fitted to an experimental vehicle. Experimental and theoretical investigations are used to investigate the performance of such a system with several different strategies employed to switch to the high-stiffness state. The use of an air suspension on the vehicle to roll into corners is also investigated, as is the possibility of exploiting the road layout by allowing the vehicle to be in a low-roll-stiffness configuration during a corner, and then to switch to the high-roll-stiffness configuration midcorner, hence ‘locking in’ a roll angle. The best rollover performance improvement that was achieved was 12.5 per cent.

For the past 40 y the scientific community has decried the inadequacy of the training of physicians and other health professionals in the subject of human nutrition. In 1997 the National Heart, Lung, and Blood Institute developed the Nutrition Academic Award (NAA) Program, an initiative to improve nutrition training across a network of US medical schools. The purpose of this funding, which began in 1998, is to support the development and enhancement of nutrition curricula for medical students, residents, and practicing physicians to learn principles and practice skills in nutrition. The NAA recipients developed the Nutrition Curricular Guide for Training Physicians, a plan to incorporate clinical guidelines into physician practice skills, create educational and assessment practice tools, and evaluate curricula, materials, and teaching tools. Dissemination of NAA activities and materials will be facilitated by a national website, presentations and publications, and consultants and advisors from the NAA nutrition education programs. The NAA Program constitutes a major new effort to enhance nutrition knowledge and skills among health care providers and to effectively apply the science of human nutrition to clinical medicine. This article describes the purpose and aims of the NAA Program, the organizational structure of the network of recipients, a profile of the recipients and individual programs at 21 medical schools, the various strategies to overcome barriers in training physicians in human nutrition, and collaborative and dissemination efforts.

To develop a scoring algorithm and evaluate the reliability and validity of scores from the Child and Adolescent Trial for Cardiovascular Health (CATCH) Food Checklist (CFC) as measures of total fat, saturated fat, and sodium intake in middle school students.Randomized, controlled trial in which participants were assigned to 1 of 3 study protocols that varied the order of CFC and 24-hour dietary recall administration. Criterion outcomes were percent energy from total fat, percent energy from saturated fat, and sodium intake in milligrams.A multiethnic sample (33% ethnic and racial minorities) of 365 seventh-grade students from 8 schools in 4 states.Multivariable regression models were used to calibrate the effects of individual food checklist items; bootstrap estimates were used for cross-validation; and kappa statistics, Pearson correlations, t tests, and effect sizes were employed to assess reliability and validity.The median same-day test-retest reliability kappa for the 40 individual CFC food items was 0.85. With respect to item validity, the median kappa statistic comparing student choices to those identified by staff dietitians was 0.54. Test-retest reliability coefficients ranged from 0.84 to 0.89 for CFC total nutrient scores. Correlations between CFC scores and 24-hour recall values were 0.36 for total fat, 0.36 for saturated fat, and 0.34 for sodium; CFC scores were consistent with hypothesized gender differences in nutrient intake.The CFC is a reliable and valid tool for measuring fat, saturated fat, and sodium intake in middle school students. Its brevity and ease of administration make the CFC a cost-effective way to measure middle school students' previous day's intake of selected nutrients in school surveys and intervention studies.

Coronary heart disease (CHD) remains the leading cause of mortality in the U.S. Innovations in reperfusion therapies can potentially reduce CHD morbidity and mortality associated with acute myocardial infarction (AMI) when treatment is initiated within the first few hours of symptom onset. However, delay in seeking treatment for AMI is unacceptably lengthy, resulting in most patients being ineligible for reperfusion therapies. The Rapid Early Action for Coronary Treatment (REACT) Trial is a four-year, 20-community, randomized trial to design and test the effectiveness of a multi-component intervention to reduce patient delay for hospital care-seeking for AMI symptoms. This manuscript describes the development and content of the theoretically-based REACT intervention and summarizes: (1) the research literature used to inform the intervention; (2) the behavioral theories used to guide the development, implementation, and evaluation of the intervention; (3) the formative research undertaken to understand better decision-making processes as well as barriers and facilitators to seeking medical care as perceived by AMI patients, their families, and medical professionals; (4) the intervention design issues that were addressed; (5) the synthesis of data sources in developing the core message content; (6) the conceptualization for determining the intervention target audiences and associated intervention components and strategies, their integration with guiding theoretical approaches and implementation theories for the study, and a description of major intervention materials developed to implement the intervention; and (7) the focus of the outcome, impact, and process measurement based on the intervention components and theories on which they were developed.

To assess differences through grade 8 in diet, physical activity, and related health indicators of students who participated in the Child and Adolescent Trial for Cardiovascular Health (CATCH) school and family intervention from grades 3 through 5.Follow-up of the 4-center, randomized, controlled field trial with 56 intervention and 40 control elementary schools.We studied 3714 (73%) of the initial CATCH cohort of 5106 students from ethnically diverse backgrounds in California, Louisiana, Minnesota, and Texas at grades 6, 7, and 8.Self-reported daily energy intake from fat at baseline was virtually identical in the control (32.7%) and intervention (32.6%) groups. At grade 5, the intake for controls remained at 32.2%, while the intake for the intervention group declined to 30.3% (P.001). At grade 8, the between-group differential was maintained (31.6% vs 30.6%, P = .01). Intervention students maintained significantly higher self-reported daily vigorous activity than control students (P = .001), although the difference declined from 13.6 minutes in grade 5 to 11.2, 10.8, and 8.8 minutes in grades 6, 7, and 8, respectively. Significant differences in favor of the intervention students also persisted at grade 8 for dietary knowledge and dietary intentions, but not for social support for physical activity. No impact on smoking behavior or stages of contemplating smoking was detected at grade 8. No significant differences were noted among physiologic indicators of body mass index, blood pressure, or serum lipid and cholesterol levels.The original CATCH results demonstrated that school-level interventions could modify school lunch and school physical education programs as well as influence student behaviors. This 3-year follow-up without further intervention suggests that the behavioral changes initiated during the elementary school years persisted to early adolescence for self-reported dietary and physical activity behaviors.

Physical inactivity has been identified as an important public health concern for youth. School and community settings can be important infrastructures for promoting physical activity (PA). This paper reviews studies of physical activity in school and community settings among preschool through college-aged persons to determine characteristics and effects of interventions. Studies in progress are included.Studies from 1980 to 1997 testing physical activity interventions in schools and community settings were identified by computerized search methods and reference lists of published reviews. Studies needed to have used a quantitative assessment of PA, used a comparison or control group, included participants who were preschool through college age, and be conducted in the United States or foreign school or community settings. Significance of effects was examined overall and for various types of interventions.Twenty-two school-based studies were reviewed, 14 completed and 8 in progress. Three studies were in countries other than the United States. The 8 studies in progress were all in the United States. Only 7 community studies were reviewed, all in the United States. Four studies were in progress. Several community studies involved a high percentage of African-American or Hispanic youth and their families. Studies showing the best results used randomized designs, valid and reliable measurements, and more extensive interventions. Some follow-up results showed PA was sustained after interventions ended.The collection of school and community studies is limited for several age groups with none below third grade and only three at college age. There are few community studies. The most is known about upper-elementary-age-students, including the first multicenter randomized trial to report significant results for increasing moderate to vigorous physical activity (MVPA) in physical education (PE) and increase vigorous PA outside of school. A number of older study designs were weak and assessments less than optimal, but studies in progress are stronger. Special attention is needed for girls, middle schools, and community settings for all youth. More objective assessments are needed for measuring PA outside of school and in younger children, since they cannot provide reliable self-report.

To assess the outcomes of health behavior interventions, focusing on the elementary school environment, classroom curricula, and home programs, for the primary prevention of cardiovascular disease.A randomized, controlled field trial at four sites with 56 intervention and 40 control elementary schools. Outcomes were assessed using prerandomization measures (fall 1991) and follow-up measures (spring 1994).A total of 5106 initially third-grade students from ethnically diverse backgrounds in public schools located in California, Louisiana, Minnesota, and Texas.Twenty-eight schools participated in a third-grade through fifth-grade intervention including school food service modifications, enhanced physical education (PE), and classroom health curricula. Twenty-eight additional schools received these components plus family education.At the school level, two primary end points were changes in the fat content of food service lunch offerings and the amount of moderate-to-vigorous physical activity in the PE programs. At the level of the individual student, serum cholesterol change was the primary end point and was used for power calculations for the study. Individual level secondary end points included psychological factors, recall measures of eating and physical activity patterns, and other physiologic measures.In intervention school lunches, the percentage of energy intake from fat fell significantly more (from 38.7% to 31.9%) than in control lunches (from 38.9% to 36.2%)(P.001). The intensity of physical activity in PE classes during the Child and Adolescent Trial for Cardiovascular Health (CATCH) intervention increased significantly in the intervention schools compared with the control schools (P.02). Self-reported daily energy intake from fat among students in the intervention schools was significantly reduced (from 32.7% to 30.3%) compared with that among students in the control schools (from 32.6% to 32.2%)(P.001). Intervention students reported significantly more daily vigorous activity than controls (58.6 minutes vs 46.5 minutes; P.003). Blood pressure, body size, and cholesterol measures did not differ significantly between treatment groups. No evidence of deleterious effects of this intervention on growth or development was observed.The CATCH intervention was able to modify the fat content of school lunches, increase moderate-to-vigorous physical activity in PE, and improve eating and physical activity behaviors in children during 3 school years.

Data on cardiovascular risk factors (body mass index, triceps and subscapular skinfolds, blood pressure, serum total cholesterol, high density lipoprotein (HDL) cholesterol, and apolipoprotein B) were collected as part of the baseline examination (fall 1991) of the Child and Adolescent Trial for Cardiovascular Health, a multicenter school-based intervention study for promoting healthful behaviors. A total of 5,106 third grade children (mean age, 8.76 years) in four states (California, Louisiana, Minnesota, and Texas) were examined. After excluding 194 children of other or unknown origin, the study population consisted of 3,530 Anglo-American children, 674 African-American children, and 708 Latino children. African-American children were the tallest by 1-3 cm (p0.0001), while Latino children had the largest body mass index (p0.05). Blood pressure levels were similar for boys and girls and among the three races, but systolic levels were 2 mmHg higher in Texas than at the other sites. Serum total cholesterol levels were 5 mg/dl higher in girls than in boys (p0.05), while HDL cholesterol levels were 2 mg/dl higher in boys (p0.05). HDL cholesterol levels were highest in African-Americans (55.5 mg/dl) compared with Anglo-Americans (50.7 mg/dl) and Latinos (51.3 mg/dl) (p0.0001).

The National Heart, Lung, and Blood Institute (NHLBI) has funded the Preventive Cardiology Academic Award (PCAA) for more than a decade. The background for focusing on physicians in training and prevention is reviewed, as well as the status of the 49 medical schools that have received the award. This report presents a synthesis of the objectives for the award, curricular approaches, and teaching strategies employed by awardees and also the framework for program evaluation. The degree of institutionalization of the programs and the diffusion nationally as well as trends in the program over the past decade are examined.

Risk factors for cardiovascular disease are commonly obtained in freshman medical students for the purpose of increasing interest and awareness in preventive cardiology. What would be a normal range of values for this select group? This paper describes the major cardiovascular risk factors for 3,811 male and female freshman medical students from eight U.S. medical schools that were obtained in a standardized fashion as part of the Preventive Cardiology Academic Award (PCAA) programs at these institutions. The distributions of height, weight, Quetelet index, systolic and diastolic blood pressures, total cholesterol, triglycerides, high-density lipoprotein cholesterol, and calculated low-density lipoprotein cholesterol are presented for male and female medical students stratified by race into white, black, Asian, and Hispanic groups. The sex and race distributions of cardiovascular risk factors such as previously diagnosed hypertension, diabetes mellitus, smoking, lack of regular exercise (three times a week or more), oral contraceptive use in women, and family history of coronary heart disease are presented. The cardiovascular risk of freshman medical students is compared to other epidemiologic studies of young adults. The use and limitations of these race- and sex-specific data on cardiovascular risk, including physiologic measurements, are discussed in the context of educational programs for medical students and house staff in preventive cardiology.

A gas phase chemi‐ionization process is used to detect O atoms produced by photodissociation of O2 and N2O. For the photon energies used here the accessible O atom states are within the ground 3P levels and the metastable 1D and 1S levels. Kinetic energies of the O atom photofragments are determined using an atomic beam time‐of‐flight technique, and the O atom angular distributions are determined by varying the angle between the direction of the photon beam and the atomic beam flight path. Dissociative transitions within the Schumman–Runge continuum of O2 and the principal vacuum ultraviolet absorption continuum of N2O yield results in agreement with previous predictions. For the dissociation of O2 at wavelengths of 120 and 124 nm, the principal dissociation products are O(3P)+O(1D); and, at these wavelengths, the O atom angular distribution is consistent with previous conclusions that predissociation is important. Using existing theories of photofragment angular distributions, an asymmetry parameter havi...

Both O(3P) and O(1D) atom fragments are observed in the photofragment spectroscopy of O3 in the Hartley band absorption region 270–300 nm. The quantum yield for O(3P) is 0.1 at 274 nm. The dissociation partner for O(3P) is O2(X3Σ−g) and that for O(1D) is O2(a 1Δg). The O2(X 3Σ−g) fragment is populated in a range of vibrational levels, v?0−10. For the O2(a 1Δg) fragment, all energetically accessible vibrational levels are populated at each energy of bombardment. In the Chappuis bands at 600 nm the O2(X 3Σ−g) photofragment is produced principally with v=0, 1. Photofragment angular distributions are measured in the uv for both O atom dissociation products at each wavelength of bombardment. A theoretical angular distribution for O(1D) is derived and the resultant prediction is in good agreement with the experimental results.

The conditions of electron-impact excitation in flowing oxygen downstream from a discharge are reinterpreted. It is shown that total oxygen mass flow is not conserved as the discharge is turned on and off, even though the inlet flow rate remains constant. The total amount of gas is diminished when the discharge is turned on, apparently due to collection of atomic oxygen by the system walls. A revised total cross section is reported for the excitation of 1304-A radiation.

Both green beans and seeds formed n-hexanol, n-hexanal and 1-octen-3-ol as the principal volatile compounds from U-14C-labeled linoleic acid but at proportionately different ratios. With U-14C-labeled linolenic acid, green beans developed mainly trans-2-hexanal, 1-penten-3-ol, 3-penten-1-ol, trans-2-hexenol and cis-3-hexenol, while seeds produced largely 1-penten-3-ol and 3-penten-3-ol with a small amount of trans-2-hexenal. Green beans showed the highest lipoxygenase activity of the several fruits and vegetables compared. Though alcohol oxidoreductase was relatively low, rapid reduction of aldehydes/ketones to alcohols was found in green beans. Green bean lipoxygenase was inhibited by cyanide and a small fraction appeared to be quite heat stable, compared to alcohol oxidoreductase which was much more unstable. The optimal activity of green bean lipoxygenase was found to be at pH 5.8.

Measurements were made of the rotational profiles of specific bands of the CO fourth-positive group (4PG). The CO 4PG bands were excited by electron impact dissociative excitation of CO2. The results are applicable to analysis of the Mariner observations of the CO 4PG in the dayglow of Mars. The results indicate that dissociative excitation of CO2 by electron impact leads to CO(A 1Pi) fragments with a rotational distribution that is highly nonthermal. The parent CO2 temperature was about 300 K in the experiment, while the fragment CO(A 1Pi) showed emission band profiles consistent with a rotational temperature greater than about 1500 K. Laboratory measurement of the reduced transmission of the hot bands by thermal CO appears to be the most direct way of determining the column density responsible for the CO(v',0) absorption of Mars.

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The absolute cross sections for the excitation of the nitrosyl cation Baer-Miescher bands, two nitric oxide bands, and several atomic nitrogen multiplets in the vacuum UV by electron impact on NO have been measured over an energy range extending from threshold to 300 eV. The variation of the dipole transition moment for the nitrosyl cation band system was also determined.

Excitation cross sections for resonance states by electron impact on atomic nitrogen and oxygen over aeronomical energy range