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We propose a method for implementing the large- N(c), large-N(f) limit of QCD at the effective Lagrangian level. Depending on the value of the ratio N(f)/N(c), different patterns of chiral symmetry breaking can arise, leading in particular to different behaviors of the eta(') mass in the combined large-N limit.
To determine whether "job strain" (defined as high psychological demands and low decision latitude on the job) is associated with increased workplace diastolic blood pressure and the left ventricular mass index, we conducted a case-control study at seven urban work sites of 215 employed men aged 30 to 60 years without evidence of coronary heart disease. After comprehensive blood pressure screening of male employees (N = 2556) at the work site, 87 cases of hypertension and a random sample of 128 controls were studied. In a multiple logistic regression model, job strain was significantly related to hypertension, with an estimated odds ratio of 3.1, after adjusting for age, race, body-mass index, type A behavior, alcohol intake, smoking, work site, 24-hour urine sodium excretion, education, and physical demand level of the job. Controlling for the above variables in subjects aged 30 to 40 years with job strain, we found that the echocardiographically determined left ventricular mass index was, on average, 10.8 g/m2 greater than in subjects without job strain. We conclude that job strain may be a risk factor for both hypertension and structural changes of the heart in working men.
OBJECTIVE: To assess the relation between body mass index (BMI) levels and various lifestyle variables related to physical activity and specific characteristics of a healthy eating pattern, using baseline cross-sectional data from the Wellness IN the Rockies project. SUBJECTS: A total of 928 males and 889 females, aged 18-99 y, recruited from six rural communities in Wyoming, Montana, and Idaho. MEASUREMENTS: Using BMI as the criterion, overweight was defined as a BMI >or=25 kg/m(2) and obesity was defined as a BMI >or=30 kg/m(2). All participants in this study completed a questionnaire that elicited sociodemographic information, self-reported height and weight, and data related to specific dietary intakes, eating-related behaviors, and physical activity behaviors and perceptions. RESULTS: Prevalence of overweight was 70% in men and 59% in women. Increased likelihood of overweight or obesity was associated with greater frequency of the following: drinking sweetened beverages such as soft drinks/soda pop, ordering supersized portions, eating while doing other activities, and watching television. Other predictors were lower frequency of participation in physical activity and the perception of not getting as much exercise as needed. CONCLUSIONS: The increased probability of having a high BMI in individuals who more often eat while doing another activity appears to be a novel finding that will need to be substantiated by additional research. The finding that the vast majority of overweight and obese respondents believed that they do not get as much exercise as needed strengthens the assertion that finding ways to increase participation in physical activity should remain a high priority in obesity prevention and intervention efforts at the community and individual levels.
The primary goal of this study was to determine the relevance of four self-reported eating behaviors (eating before bedtime, eating between meals, feeling hungry within 3 h of eating, and eating beyond satiation) as risk factors for overweight and obesity. The sample consisted of 35- to 49-year-old, premenopausal African American (n=580) and Caucasian (n=398) women, randomly selected from the membership of a large urban prepaid health plan. Eating beyond satiation was the only behavior associated with body mass index (BMI). The odds of becoming obese increased 6-fold for Caucasian women and 15-fold for African American women who ate beyond satiation everyday compared to those who rarely or never ate beyond satiation. Additionally, eating beyond satiation was also the only eating behavior associated with the age of obesity onset. Focusing on this eating behavior in weight loss programs may be important.
A novel class of glycolipids, assigned the trivial name blaberosides, was isolated from whole head tissues of the giant cockroach (Blaberus colosseus). The class consists of two closely related families, blaberoside I and blaberoside II, each containing species differing by 26 atomic mass units. The structure of these gentiobiose-based glycoglycerolipids was elucidated by chromatographic behavior, nuclear magnetic resonance spectroscopy, mass spectrometry, and analysis of chemical degradation products and derivatives. Species in the blaberoside I family have been identified as 2-O-[6'-O-(6"-O-3-hydroxy-11-eicosenoyl-beta-D-glucopyranosyl)-bet a-D- glucopyranosyl]-3-(hexadecyloxy)-1-(3-hydroxy-11-eicosenoyl)-1,2-p ropanediol (blaberoside Ia) and 2-O-[6'-O-(6"-O-3-hydroxy-11-eicosenoyl-beta-D-glucopyranosyl)-bet a- D-glucopyranosyl]-3-(6-octadeceloxy)-1-(3-hydroxy-11-eicosenoyl )-1,2- propanediol (blaberoside Ib). Two smaller homologs of the blaberoside II family were discerned to be 2-O-[6'-O-(6"-O-3-hydroxy-11- eicosenoyl-beta-D-glucopyranosyl)-beta-D-glucopyranosyl]-3-(hex ade cyloxy)- 1,2-propanediol (blaberoside IIa), and 2-O-[6'-O-(6"-O-3-hydroxy-11-eicosenoyl-beta-D- glucopyranosyl)-beta-D-glucopyranosyl]-3-(4-octadeceloxy)-1,2-prop anediol (blaberoside IIb). These compounds are unique because they are animal origin glyceroglycolipids with a highly flexible gentiobiose backbone, and a beta-linkage of the carbohydrate to the glycerol ether at the 2 position rather than the usual 1 position.
Natal dispersal, the permanent departure of an individual from its birth site, is sex biased in most mammals, with males dispersing at higher rates or over greater distances than do female conspecifics. Because dispersal movements may be energetically expensive, their occurrence should theoretically be influenced by energy availability. Moreover, the male bias typical of mammalian dispersal suggests that this behavior might be mediated by gonadal androgens. Using free-living Belding's ground squirrels (Spermophilus beldingi) as subjects, we provisioned juveniles with extra food to evaluate energetic influences on male dispersal behavior. Provisioning increased body mass and body fat of juvenile males and caused them to disperse at younger ages, but did not affect blood glucose levels. Dispersing males were fatter than same-aged males that had not yet dispersed. Moreover, body fat of provisioned and unprovisioned males did not differ when evaluated relative to the week during which they dispersed, suggesting that there may be a fat threshold for dispersal. In a second experiment, we measured plasma concentrations of testosterone (T) in provisioned and unprovisioned, free-living juveniles to evaluate the hypothesis that male dispersal behavior is activated by concurrent high levels of T. We observed no increase in plasma T associated with dispersal by juvenile males, no sex differences in circulating T among juveniles, and no effects of food provisioning on juvenile T levels. In a third experiment with free-living S. beldingi, we concurrently altered early androgen exposure by treating females with T at birth and manipulated energy availability by food provisioning. Perinatal T-treatment increased the likelihood of dispersal among juvenile females. Provisioning increased body mass and body fat of juveniles and caused males and T-treated females to disperse at significantly younger ages than either their unprovisioned counterparts or the few provisioned control females that dispersed. These results suggest that early T exposure in this species determines the probability of dispersal, whereas the amount of energy an individual has stored as fat strongly influences the timing of dispersal. Early T exposure also appears to cause the timing of dispersal to respond to energy availability and body fat in a male-typical way, possibly by organizing masculine mass and fat thresholds for dispersal.
Concentrated fractions of vitamin K from bovine liver were purified by thin-layer chromatography and fractions were analyzed by UV spectroscopy and mass spectrometry. The chromatographic behavior of the purified vitamins was compared with that of known compounds on thin layers of silica gel, either untreated or impregnated with silver nitrate or paraffin. The principal forms of vitamin K recovered from bovine liver were highly lipophilic. Two fractions were obtained which collectively gave identifiable mass spectra of menaquinone-10, menaquinone-11, and menaquinone-12.
A recombinant plasmid for expression of full-length human DNA ligase I (phLig-I) was constructed in a plasmid/phage chimeric vector, pTD-T7N, which was derived from pUC118 by oligonucleotide-directed mutagenesis. The insert contained a 2757-base pair coding sequence for a whole human DNA ligase I and an extra ACC codon adjacent to the ATG initiation codon. This ACC codon was required for achieving high levels of expression of full-length DNA ligase I in Escherichia coli strain BL21. The recombinant plasmid, which was designed to exploit the T7 late promoter and the ATG initiation codon for beta-galactosidase was transfected into E. coli BL21 cells that express T7 RNA polymerase. The recombinant clone produced relatively high levels of DNA ligase I with a molecular mass of 130 kDa, as estimated by SDS-polyacrylamide gel electrophoresis. The DNA ligase was purified to near-homogeneity by the two-step column chromatographic procedure from BLphLig-I cells that had been induced with isopropyl beta-D-thiogalactoside. The specific activity, chromatographic behavior, kinetic properties, molecular mass, and antigenicity of the recombinant human DNA ligase I were indistinguishable from those of purified mammalian DNA ligase I. Metabolically labeling experiments with 32P(i) indicate that the recombinant DNA ligase I was present as an enzyme-AMP reaction intermediate, but not as a phosphoprotein, in the E. coli cells.
The sensing behavior of polymer-coated resonant cantilevers for mass-sensitive detection of volatile organic compounds was investigated. Industrial complementary metal oxide semiconductor (CMOS) technology combined with subsequent CMOS-compatible micromachining was used to fabricate a single-chip system comprising the transducers and all necessary driving and signal-conditioning circuitry. An analytical model was developed to describe the mass-sensing mechanism of polymer-coated resonant cantilevers. The model was validated by measurements of various gaseous analytes. As an exemplary application, the quantitative analysis of a binary mixture using an array of four cantilevers is described. Experimental results are given for the concentration prediction of a mixture of n-octane and toluene. Finally, it was established that the limit of detection achieved with cantilever sensors is comparable to that of other acoustic wave-based gas sensors.
Self-esteem has been hypothesized to be lower in obese adolescents relative to their normal weight peers and to be an important factor in preventing or reversing obesity. The present study examined the relationship between obesity and self-esteem cross-sectionally and prospectively over three years in a cohort of 1278 adolescents in grades 7 to 9 at baseline. Cross-sectional analyses revealed an inverse association between physical appearance self-esteem and body mass index in both males and females. In females, body mass index was inversely associated with global self-esteem, close friendship, and behavioral conduct self-esteem. In males, body mass index was inversely associated with athletic and romantic appeal self-esteem. Prospectively, in females, physical appearance and social acceptance self-esteem at baseline were inversely related to body mass index three years later. Baseline self-esteem was unrelated prospectively to change in body mass index in males. All associations were modest in magnitude. These results suggest that in a middle class white sample of adolescents, self-esteem specific to physical appearance is modestly associated with body mass index. Low self-esteem does not appear to predict the development of obesity over time.
We assessed the relationship between potential risk factors for coronary heart disease, including type A behavior, leisure time physical activity, and stress in a young black adult population. The study population consisted of 192 black college freshmen at the University of Pittsburgh. The mean age of male subjects was 18.4; the mean age of female subjects was 18.5 years. No significant sex differences were noted for body mass index, type A behavior, stress, or physical activity levels. For both men and women, type A (Framingham) was positively correlated with stress. Only among women was there a positive association between type A (Bortner) and physical activity.
An exact steady-state solution of the stochastic equations governing the behavior of a gene regulated by a self-generated proteomic atmosphere is presented. The solutions depend on an adiabaticity parameter measuring the relative rate of DNA-protein unbinding and protein degradation. The steady-state solution reveals deviations from the commonly used Ackers et al approximation based on the equilibrium law of mass action, allowing anticooperative behavior in the "nonadiabatic" limit of slow binding and unbinding rates. Noise from binding and unbinding events dominates the shot noise of protein synthesis and degradation up to quite high values of the adiabaticity parameter.
BACKGROUND: The aim of the present study was to elucidate both environmental and behavioral factors that influence body mass index (BMI, kg/m2) among Japanese children from ages 3-6. METHODS: In 1992 (at age 3) and 1995 (at age 6), 8170 6-year-old children (4176 boys and 3994 girls) were surveyed using a questionnaire on both body build (height and weight) and lifestyle. The correlation between BMI for 3-year-olds and for 6-year-olds were analyzed. From the temporal changes of body build between age 3 and 6 years, we categorized children into four groups: group 1, normal at both age 3 years and 6 years (normal/normal); group 2, overweight at age 3 years and normal at age 6 years (overweight/normal); group 3, normal at age 3 years and overweight at age 6 years (normal/overweight); and group 4, overweight at both age 3 years and 6 years (overweight/overweight). The authors compared the four groups with each other according to sex, concerning frequencies of children who matched the categories of environmental and behavioral factors. Each factor was tested using the chi2 test. Overweight children were defined as those whose BMI value was age-sex specific in the 90th percentile or more. RESULTS: A significant correlation was found between body builds for children aged 3 and 6 years in both genders (boys, r = 0.559, P < 0.01; girls, r = 0.584, P < 0.01). Significant factors associated with overweight children were diet (eating rice, green tea, eggs, meat, but less breads and juice), rapid eating, short sleep duration, early bedtime, long periods of television viewing, avoidance of physical activity, and frequent bowel movement. DISCUSSION: Temporal changes in BMI from age 3 years to 6 years are significantly associated with both environmental and behavioral factors at age 6 years. The results of this study may be useful for health promotion programs designed to prevent obesity during the early stages of childhood.
In the past, it has been difficult to grow human diploid fibroblast cells at clonal densities. Newly devised cell culture media and rigorously controlled environmental conditions have greatly increased the ease with which such cells can be cloned. The present work was undertaken to determine whether, under appropriate conditions, diploid fibroblast cells from human embryonic lung, grow as well at clonal densities as in mass culture. The parameters studied were: (1) population doubling time, (2) in vitro proliferative capacity, (3) attachment, (4) percentage of non-dividing cells. In all cases essentially the same results were obtained for cultures at clonal densities and mass cultures. These results indicate that the behavior of these types of cells in clonal culture can be used to infer the behavior of individual cells and clones within a mass culture.
Previous research has demonstrated that increasing dietary choline during early development can have long-lasting effects on cholinergic (Ch) function that are correlated with improvement of spatial memory ability in rats. The present study is designed to further our understanding of these organizational changes in brain and behavior by examining the effects of spaced vs. massed trials. A third of the rats (n=10) were supplemented with choline chloride prenatally by adding it to the drinking water of their dams. Another third were made deficient of choline during early development by removing choline from the dams diet. The remaining rats served as untreated controls. Postnatally, the offspring were maintained on a choline-sufficient diet and at 120 days of age they began 12-arm radial maze training. The maze data revealed two major effects of early choline availability: (1) Both choline-supplemented and choline-deficient rats performed more accurately than control littermates when trials were spaced. These differences in spatial ability did not appear to be a function of differential response or cue-use strategies. (2) Choline-supplemented rats showed little proactive interference when trials were massed; whereas control rats demonstrated moderate levels and choline-deficient rats exhibited high levels of proactive interference as a function of massed trials. These data suggest that the behavioral consequences of early dietary availability of choline may involve the modification of the discriminative abilities used to attend to stimuli that demarcate the end of one trial and the start of another as well as the capacity for remembering the locations that have been visited during a trial.
Participation in a health promotion program for 192 overweight and obese adults with mental retardation was associated with behavior change resulting in reduction of body mass index-BMI (weight in kg, divided by height in meters, squared) by the end of the program. We analyzed the mediating and intermediate factors contributing to weight reduction and found knowledge and exercise to be the primary contributing factors. The curriculum emphasized exercise, nutritional choices, and stress reduction. Participation in the program was associated with a reduction of 0.8 BMI or approximately 2.3 kg for 26% of the participants. Increased knowledge about healthy diet and exercise was the most significant mediator of program impact on BMI.
OBJECTIVE: A study was undertaken to examine the attitudes and practices of health care providers in the assessment and treatment of overweight and obese children and adolescents. This study describes the study design and the practice settings and person characteristics of the practitioners included in this study. METHODS: A needs assessment questionnaire was developed by a working group consisting of researchers, clinicians, educators, and representatives of the Maternal and Child Health Bureau, Health Resources and Services Administration (Department of Health and Human Services), National Center for Education in Maternal and Child Health, International Life Sciences Institute, and Harris Interactive, Inc. The questionnaire consisted of 35 questions divided into 3 topic areas and was disseminated to a sample of pediatricians (n = 1088), pediatric nurse practitioners (n = 879), and registered dietitians (n = 1652). RESULTS: Despite a low response rate (33% for pediatric nurse practitioners, 27% for registered dieticians, and 19% for pediatricians), descriptive data were obtained about a variety of practitioner characteristics. Some significant differences were observed across practitioner groups and between genders in regard to years in practice, body mass index, and dietary and physical activity behaviors. Significant relationships were also observed in some practitioner groups between body mass index and compliance with dietary and physical activity guidelines. CONCLUSIONS: Our data show there is a wide variance in practitioner characteristics, particularly in regard to gender, years of practice, body mass index, and obesity-related behaviors. It is hoped the analyses presented in this and in the subsequent articles will provide useful information on current attitudes and practices and will contribute to improvements in the treatment of overweight children and adolescents.
The hypothesis was put forward that, along with the regulation of mass center projection, the system of upright posture control stabilizes the deviation of pressure center from the position of the mass center projection. The regularities in the behavior of the trajectories of pressure center and mass center projection were analysed. Experimental evidence was obtained supporting the validity of the hypothesis. The structure of the control system that corresponds to the new understanding of the variables being regulated during the maintenance of vertical posture was considered.