Lead (Pb), cadmium (Cd), mercury (Hg), and arsenic (As) are among the top 10 pollutants of global health concern. Studies have shown that exposures to these metals produce severe adverse effects. However, the mechanisms underlying these effects, particularly joint toxicities, are poorly understood in humans. The objective of this investigation was to identify and characterize prevalent combinations of these metals and their species in the U.S. NHANES population to provide background data for future studies of potential metal interactions. Exposure was defined as urine or blood levels medians of the NHANES 2007-2012 participants 6 years (n = 7408). Adjusted-odds ratios (adj-OR) and 95% confidence intervals were determined for covariates (age, gender, and race/ethnicity, cotinine and body mass index). Species-specific analysis was also conducted for As and Hg including iAs (urinary arsenous acid and/or arsenic acid), met-iAs (urinary monomethylarsonic acid and/or dimethylarsinic acid), and oHg (blood methyl-mercury and/or ethyl-mercury). For combinations of As and Hg species, age- and gender-specific prevalence was determined among NHANES 2011-2012 participants (n = 2342). Data showed that approximately 49.3% of the population contained a combination of three or more metals. The most prevalent unique specific combinations were Pb/Cd/Hg/As, Pb/Cd/Hg, and Pb/Cd. Age was consistently associated with these combinations: adj-ORs ranged from 10.9 (Pb/Cd) to 11.2 (Pb/Cd/Hg/As). Race/ethnicity was significant for Pb/Cd/Hg/As. Among women of reproductive age, frequency of oHg/iAs/met-iAS and oHg/met-iAs was 22.9 and 40.3%, respectively. These findings may help prioritize efforts to assess joint toxicities and their impact on public health.

There are racial/ethnic differences in prevalence of overweight and obesity in 2-5 year old children. An important factor in early obesity development for all children includes unhealthy dietary patterns and movement behaviors. Child-care centers can be a health intervention target since 60% of young children spend substantial time in these facilities. PURPOSE: The purpose of this study is to examine the relationship of race/ethnicity, dietary intake and movement by Body Mass Index (BMI) percentile in children attending child-care centers. METHODS: An observational study at child-care centers was conducted during 2011-2014. BMI was calculated from measured height and weight and BMI percentile was calculated based on age and sex. Parental report of race included American Indian/Alaska Native (AI/AN), white and black. Dietary intake was determined from observed lunch food consumption and analyzed using dietary analysis software. Independent dietary variables used included sugars (g), total kcal and total fruits-and-vegetables consumed. Physical activity intensity and duration was measured for the entire school day using waist-worn accelerometers. Data was recorded and analyzed with age-specific cut points to determine intensity. Independent movement variables included minutes of sedentary, light and moderate-to-vigorous physical activity. RESULTS: Participants included 174 children, age 3.8±0.7, 51% male, AI/AN 32%, white 46% and black 20%. AI/AN had the highest mean BMI percentile (72.2±25.8) compared to white (62.9±27.8, p=0.02) and black (65.2±27.8, p=0.05). When a second race was included for AI/AN children of mixed heritage, AI/AN-only children (79.8±21.8) had a higher BMI percentile compared to AI/AN-mixed children (61.8± 27.3, p<0.05). There were no significant differences found between race/ethnicities in movement behaviors. After adjusting for race, only higher kcal consumption (β=0.039, SE=0.01, p=0.004) was associated with higher BMI percentile. CONCLUSION: In support of previous research, AI/AN children had a higher mean BMI percentile than other races. This difference was further amplified when AI/AN-only children were examined, AI/AN-mixed BMI percentile was not different than white. After adjusting for race, total kcal was still associated with BMI Percentile.

School-based interventions can reach children and adolescents and aid in reducing the prevalence of childhood obesity. A physical education class that engaged middle school students in a daily 1-mile walk or run and other team sports was developed in a rural school in southwestern Oklahoma with a large American Indian population. Body mass index z scores decreased among boys and were stable among girls in the intervention group compared with students who did not participate in the intervention. A daily required walk or run may help to establish a physical activity habit with all of its associated benefits.

We have successfully designed, fabricated, installed and tested a super compact X-Band SLED system at SLAC. It is composed of an elegant 3dB coupler / mode converter / polarizer and a single spherical energy storage cavity with high Q0 of 94000 and diameter less than 12 cm. The available RF peak power of 50 MW can be compressed to a peak average power of more than 200 MW in order to double the kick for the electron bunches in a RF transverse deflector system and greatly improve the measurement resolution of both the electron bunches and the Xray FEL pulses. High power operation has demonstrated the excellent performance of this RF compression system without RF breakdown, sign of pulse heating and RF radiation. The design physics and fabrication as well as the measurement results will be presented in detail. INTRODUCTION This diagnostics for X-ray temporal measurement based on the transverse deflectors, the magnetic spectrometer and the Ce:YAG screen located downstream of the FEL undulator has been intensively used at the LCLS operation [1]. Its layout is shown in Figure 1. Figure 1: Diagnostics layout of the X-ray temporal measurement at the LCLS. In order to improve temporal resolution, we have designed and fabricated a novel super compact SLED system to double the peak deflection. [2] This paper describes its principle, design and technical advances. DESIGN OF SUPER COMPACT SLED SYSTEM More than forty years ago, SLAC developed the SLED system to obtain high peak RF power in exchange for the RF pulse length reduction [3]. The key components of a SLED system include a 3dB coupler with two 90° apart power ports and two high Q energy storage cavities. The LCLS deflector is made of two traveling structures, Each one is a 1.0 m long, constant impedance structure with transverse impedance of 41.9 MΩ/m, filling time Tf=106 ns (group velocity of -3.165 % speed of light) and attenuation factor τ=0.62 Neper. If we assume the similar average RF power of 106 ns pulses for both the SLEDed pulse and non SLEDed flat pulses to feed a backward wave constant impedance deflector, the corresponding kick voltages are shown in Fig. 2. Figure 2: Kick voltage along the deflector structure. We need to optimize the SLED system by calculating its total gain for various coupling coefficients for the high Q0 cavity, its Q values and pulse length. Figure 3 shows that the highest gain of larger than factor of 2 can be obtained for Q0 ~9x10 and 1μs pulses if the over-coupling coefficient β is optimized to be 7-8 for 11424 MHz. Figure 3: SLED gain as function of pulse widths and Q0 values of energy storage cavity. Unified 3dB Coupler / Mode convertor / Polarizer Having all the basic functions of a 3dB coupler, a much more compact and elegant dual-mode circular polarizer was developed to transform the TE01 mode in a rectangular waveguide into two polarized TE11 modes in quadrature in a circular waveguide as shown in Fig. 4. Figure 4: Schematic view of the dual-mode polarizer. The input TE01 mode converts to both TE01 and TE02 modes in a widened rectangular waveguide region, and their magnetic field components will couple to two per___________________________________________ * Work supported by DOE contract DE-AC03-76SF00515. † Email address jywap@slac.stanford.edu Proceedings of IPAC2016, Busan, Korea MOOCA01 07 Accelerator Technology T06 Room Temperature RF ISBN 978-3-95450-147-2 39 C op yr ig ht © 20 16 C C -B Y3. 0 an d by th e re sp ec tiv e au th or s pendicular polarized TE11 modes in the circular waveguide. We adjusted geometries so the phases of the two polarized modes are in quadrature. If the circular waveguide feeds a spherical cavity as shown in Fig. 5, two corresponding polarized sphere modes will act in similar fashion to the two modes from the two cylinders in a traditional SLED system. Figure 5: Construction of the new SLED system. High Q Sphere Cavity The electrical vector potential F for all modes in a sphere with radius r=a can be described as: ( ) = (cos ) cos sin , where Ĵn is the spherical Bessel Function and Pn are the associated Legendre Polynomials with m ≤ n. For TE modes, Eφ = Hθ = 0 at surface r=a. This means Ĵn (unp)=0. Therefore, the sphere radius can be calculated using wave propagation constant k and value of unp. = = × = 0.41767 ( ) Sphere radius is independent with mode index m, there are numerous degenerative modes with the same m. In our case, we have chosen TEm14 modes. There are three possible modes: ( ) = 14.066 cos ( ) = 14.066 sin cos ( ) = 14.066 sin For a perfect spherical cavity, these three modes have the same mode patterns except that they are rotated 90° in space from each other, which can be seen in following Fig. 6 and Fig. 7. In reality, they can be slightly distinguished in frequencies due to the perturbation from the coupler port. The TE014 mode is higher in frequency and very weakly undercoupled due to the feed orientation. Another interesting property is the sole dependence of Q0 on the sphere radius without depending on the mode types. The quality factor Q0 for TE Modes is = δ is the skin depth, for copper it is 0.61μm at 11 GHz. Figure 6 shows two polarized TE114 modes of 11424 MHz as working SLED modes with Q0~9.5x10 and overcoupling of 7-8 and a TE014 mode with 7 MHz higher in frequency, which has very weakly undercoupled due to its field pattern. Figure 6: Two polarized TE114 modes (middle and right) and one TE014 mode (left). Figure 7 schematically shows the wave propagation in the SLED system. Figure 7: The wave propagation in the SLED system. Coupler Design The coupling iris between circular guide and sphere cavity was optimized to reduce the RF pulse heating. The final iris has rounding radius of 3 mm to make the pulse heating less than 40°C for 1.5 μs square pulses at peak power of 50 MW. Mechanical Design and Assembly Figure 8 and 9 show some pictures for the fabricated polarizer and SLED assembly. Figure 8: 3dB Coupler/ Mode Convertor / Polarizer. Figure 9: Mechanical design and fabricated SLED assembly. A provide adequate pumping, a vacuum port was built on the bottom of the polarizer (see Fig. 9). Tuning of the sphere cavity was well performed by combination of machining away a ridge in the sphere MOOCA01 Proceedings of IPAC2016, Busan, Korea ISBN 978-3-95450-147-2 40 C op yr ig ht © 20 16 C C -B Y3. 0 an d by th e re sp ec tiv e au th or s 07 Accelerator Technology T06 Room Temperature RF equator during cold test and minor push-pull tuning on the top region of the finished sphere. MICROWAVE MEASUREMENTS Figures 10, 11 and 12 show the excellent performance of the polarizer by the microwave measurements. Figure 10: The transmission is -0.04 dB for two back-toback polarizers with the transmission efficiency of 99%. The reflection from the input port is negligible -45db. Figure 11: Isolation between in/out WR90 ports is -31 db. Figure 12: Proof of full SLEDed power transmission with the end of circular waveguide shorted. The cold test for the fabricated SLED system has demonstrated great consistency of its microwave properties with the theoretical design as shown in Figs. 13 and 14. Figure 13: Frequency scan showing the two overlapped working modes TE114 (large) and a 7 MHz higher frequency mode TE014 (small) for theoretical design (left and measurement (right). Figure 14: Smith Chart showing overcoupled working mode (large circle) and undercoupled mode (tiny circle) for theoretical design (left) and measurement (right). HIGH POWER OPERATION The SLED system was high power processed on an XBand station at the SLAC Test Lab, then was installed at the LCLS between the klystron and upstream transmission line to the deflectors as shown in Fig. 15. The RF waveforms for the high power operation in comparison with the theoretical calculation is shown in Fig. 16. Maximum kick has increased from 45 MV without SLED to 85 MV during recent operation. Full klystron power has not been reached the maximum. It was limited by a power line AC transformer, already updated, we are waiting for a machine maintenance time slot to push klystron power from present level to 50 MW. The maximum kick will reach the final goal of 95 MV (~10% more). The system has been running encouragingly stable without breakdown, sign of pulse heating, outgassing or RF contact radiation near the SLED cavity body. Figure 15: The SLED system has been installed. Figure 16: High power operation waveforms for theoretical design (left and measurement (right). SUMMARY This progress has proved great success for the X-Band super compact SLED system R&D. The design can be easily extended to Cor S-Band. A broad range of future applications are on the horizon. Possibilities for flat top pulse compression system are under studies. REFERENCES [1] C. Behrens et al., Nature Communications, 5. 3762 2014. [2] J, W. Wang et al. LINC2014, 2014. [3] Z.D. Farkas et al., SLAC-PUB-1453, June, 1974. Proceedings of IPAC2016, Busan, Korea MOOCA01 07 Accelerator Technology T06 Room Temperature RF ISBN 978-3-95450-147-2 41 C op yr ig ht © 20 16 C C -B Y3. 0 an d by th e re sp ec tiv e au th or s

AIM:To study the trends of major causes of visual impairment (VI) in adults in Sichuan, China and evaluate the effect of aging on the trends.METHODS:We used data from the National Sample Survey on Disabilities (NSSD) in Sichuan province conducted in 1987 and 2006. The age-adjusted prevalence of major causes of VI and the prevalence stratified by age in each cause were calculated and compared. The association between age and each cause of VI was also analyzed.RESULTS:Retinal disease increased and became the second leading cause of VI in 2006 while blinding trachoma decreased markedly. Cataract and non-trachomatous corneal diseases were among the leading causes of VI in both years. We found associations between age and causes of VI, with age showing the strongest association with cataract and relatively lower associations with other causes.CONCLUSION:In the last two decades, dramatic changes occurred in the major causes of VI with significantly increased retinal disease and decreased blinding trachoma. Aging of the population might be an important factor accounting for the changed trends of VI. Understanding the prevalence of VI, its major causes and trends over time can assist in prioritizing and developing effective interventional strategies and monitoring their impact.

The RF magnetic field enhancement between two closely spaced protrusions on a metallic surface has been studied theoretically. It is found that a large enhancement occurs when the field is perpendicular to the gap between the protrusions. This mechanism could help explain the melting that has been observed on cavity surfaces subjected to pulsed heating that would nominally be well below the melting temperature of the surface material. To test this possibility, an experiment was carried out in which a pair of copper “pins” was attached to the base plate of an X-band cavity normally used to study pulsed heating. Melting was observed between the pins when the predicted peak temperature was near or exceeded the copper melting temperature. INTRODUCTION We have theoretically investigated the effect of a pair of identical, very small diameter, parallel, cylindrical, metallic, surface protrusions on an applied RF magnetic field in which the flux lines thread between them. The pins concentrate the flux lines, enhancing the magnetic field on the inner surfaces [1]. This is to be distinguished from the magnetic enhancement from general surface features, for example, those associated with sharp edges in normal conducting structures [2] and surface bumps and pits in superconducting cavities [3-6], where the radius of curvature of the surface is the main factor in determining the enhancement, as opposed to the gap opening between above-surface structures. To verify our theoretical findings and explore the surface damage due to high pulsed heating temperatures (close to the melting point), we fabricated 4 pairs of short, cylindrical, copper pins and brazed them to a sample plate of a TE01 cavity used for pulsed-heating studies [7]. The electric field on the surface of the plate is nominally zero so only magnetic field effects are observed. The pins have a height of 2.5 mm and radius of 0.5 mm. They were all located at the radius of maximum pulsed heating on the sample plate. Different gap distances were used for the pairs, two that should produce a magnetic field enhancement of about 3.3 and two with about 2.3. This is illustrated in Fig. 1, where the solid line is the result of a simulation for the pin size, and the squares indicate the enhancement deduced from the measured pin spacing. The surface field around the pin pair is shown in the color maps of Fig. 2. The magnetic field is enhanced almost uniformly from the bottom of the pin to the start of its rounded tip. The electric field, which nominally increases linearly above the surface, is enhanced in small areas at the rounded tips. The ratio of maximum electric field to the maximum magnetic field is about 190 Ω with a magnetic field enhancement of 3.2. Figure 1: Peak surface magnetic field enhancement between the pin pairs with different gap distances.

A new klystron based X-band rf power source operating at 11.994 GHz has been installed and started to be commissioned at CERN in collaboration with CEA Saclay and SLAC for CLIC accelerating structure tests. The system comprises a solid state high voltage modulator, an XL5 klystron developed by SLAC, a cavity based SLED type pulse compressor, the necessary low level rf system including rf diagnostics and interlocks and the surrounding vacuum, cooling and controls infrastructure. The system is designed to produce up to 50 MW rf pulses of 1500 ns pulse width and 50 Hz repetition rate. After pulse compression, up to 100 MW of rf power at 250 ns pulse width will be available in the structure test bunker. This paper describes in more detail this setup and the process of commissioning which is necessary to arrive at the design performance.

IntroductionStudies have assessed rates of childhood obesity in diverse populations, but few have been able to compare the weight status of American Indian and white children living in the same community and attending the same schools. The objective of this study was to measure and compare the weight status of American Indian and white elementary school students (kindergarten through 5th grade) from 2005 through 2009 in an Oklahoma school district.MethodsWe assessed height, weight, age, and sex to calculate body mass index, body mass percentile, and categorical weight status of students, based on the Centers for Disease Control and Prevention 2000 Growth Charts. We used binomial regression to generate risk ratios (RRs) to compare student weight status by race, sex, and age.ResultsAn average of 753 students was measured in each year; mean age was 8.3 years. From 2005 through 2009, 45.4% of American Indian students and 65.1% of white students were healthy weight or underweight. Greater proportions of American Indian children were very obese (weighted average RR, 2.0); obese (weighted average RR, 1.6), or overweight (weighted average RR, 1.8) compared with white children. The overall prevalence of excess weight changed little during the study period.ConclusionAmerican Indian children had a greater risk of being overweight, obese, or very obese than white children from the same rural environment.

Purpose: The aim of this study was to assess the changes in the prevalence of visual impairment due to blinding trachoma in Sichuan, China between 1987 and 2006.Methods: Over 125,000 residents of Sichuan province participated in the National Sample Survey on Disabilities, conducted in both 1987 and 2006. Changes in the prevalence of visual impairment due to blinding trachoma were analyzed while accounting for other factors including gender, age and residence (urban vs. rural).Results: In 1987, blinding trachoma ranked second among the eight major visual impairment causes assessed with a prevalence of 172.9 (95% CI: 152.2-196.6) per 100,000, while in 2006 it ranked eighth with a prevalence of 58.1 (95% CI: 45.5-73.0) per 100,000. The prevalence in 2006 decreased significantly compared to 1987 in both rural and urban areas, as well as in both genders. Furthermore, in both 1987 and 2006, visual impairment due to blinding trachoma tended to be concentrated among individuals over 40, although it was also seen in young people.Conclusion: In the past 20 years, the prevalence and percentage of visual impairment due to blinding trachoma was significantly reduced in Sichuan province, and we anticipate a further decrease in the future.

Objectives. The aims of the present study were to estimate the prevalence and risk factors of asthma among a sample of American Indian youth and to evaluate survey instruments used in determining asthma prevalence and risk factors. Methods. Three hundred and fifty-two adolescents aged 9 to 21 years enrolled in an Indian boarding school completed an asthma screening. The survey instruments were a written questionnaire and a video-illustrated questionnaire prepared from the International Study of Asthma and Allergies in Childhood (ISAAC), school health records, and a health questionnaire. Participants also underwent spirometry testing. Results. The prevalence of self-reported asthma varied from 12.7% to 13.4% depending upon the instrument used and the questions asked. A history of hay fever, respiratory infections, and family history of asthma were found to be risk factors for asthma by all instruments. Female gender and living on a reservation were significantly associated with asthma by some, but not all, instruments. Airway obstruction was highly associated with one asthma symptom (wheeze) shown in the video questionnaire. Associations for most risk factors with asthma were strongest for the video questionnaire. Conclusions. The prevalence of self-reported asthma among these American Indian youth was similar to rates reported for other ethnic groups. The video-based questionnaire may be the most sensitive tool for identifying individuals at risk for asthma.

Tobacco use among American Indians has a long and complicated history ranging from its utilization in spiritual ceremonies to its importance as an economic factor for survival. Despite this cultural tradition and long history, there are few studies of the health effects of tobacco in this population. The Strong Heart Study is a prospective observational study of cardiovascular disease (CVD) in 13 American Indian tribes in Arizona, Oklahoma, and North and South Dakota with 4,549 participants. Baseline examinations were followed by two examinations at regular intervals and 16 years of morbidity and mortality follow-up. Hazard ratios (HRs) for non-fatal CVD for current smokers vs. non-smokers after adjusting for other risk factors were significant in women (HR = 1.94, 95% CI 1.54 to 2.45) and men (HR = 1.59, 95% CI 1.16 to 2.18). Hazard ratios for fatal CVD for current smokers vs. non-smokers after adjusting for other risk factors were significant in women (HR = 1.64, 95% CI 1.04 to 2.58), but not in men. Individuals who smoked and who were diagnosed with diabetes mellitus, hypertension or renal insufficiency were more likely to quit smoking than those without these conditions. On average, American Indians smoke fewer cigarettes per day than other racial/ethnic groups; nevertheless, the ill effects of habitual tobacco use are evident in this population.

BACKGROUND:The efficacy of physical activity in improving cardiovascular disease (CVD) risk profiles has been well established. However, the effectiveness of health promotion programs implemented at the community level remains controversial. This study evaluated a school-based work-site physical activity program.METHODS:Using a community-based participatory research model, a work-site wellness intervention was implemented in a rural public school system in Southwestern Oklahoma. During the 2005-2006 school year, 187 participants (mean age 45 years) completed a pre intervention screening for CVD risk factors followed by a physical activity promotion program. Post intervention screening was conducted after a 6 month period. During both screening sessions, body composition, blood pressure, lipids, glucose and self-reported physical activity levels were assessed. The focus of the intervention was on promoting physical activity. Opportunities for in school physical activity were created by marking hallways, adding a treadmill in each school, and allowing teachers to use planning periods for physical activity.RESULTS:During the post intervention screening, compared to pre intervention levels, participants had lower total, low, and high density lipoprotein-cholesterol (t = 5.9, p < 0.0001, t = 2.6, p = 0.01, and t = 13.2, p < 0.0001 respectively), lower systolic blood pressure (t = 2.9, p = 0.004), and higher self-reported physical activity levels (Sign t = -1.901, p = 0.06).CONCLUSIONS:A successful participatory program was associated with improvements in several CVD risk factors among school employees. Limitations of this study such as seasonal variation in the outcome variables and lack of a control group limit our ability to draw solid conclusions about the effectiveness of the intervention.

CONTEXT Screening to identify individuals at risk for cardiovascular disease is sorely needed in rural areas of Oklahoma. OBJECTIVE The Healthy Adults Project was started as a screening program for public school employees in a rural school district in southwest Oklahoma. DESIGN, SETTING, AND PARTICIPANTS The screening project is a collaborative effort between the Anadarko Public School district and the University of Oklahoma Prevention Research Center. Two hundred twenty-four (224) employees participated in the screening in 2004, and 206 employees participated in 2005. FINDINGS Approximately 50% of females and 80% of males had two or more modifiable risk factors for cardiovascular disease in 2004 and 2005. CONCLUSIONS Worksite screening is a valuable tool to raise awareness of risk factors for cardiovascular disease, particularly in less densely populated areas where wages are low and few preventive services are available. Knowledge of individual risk is the first step in improving health outcomes.

BACKGROUND:There are few studies of the prevalence of elevated blood pressure (BP) that include American Indian school children. Therefore, the intent of this study was to examine the relationships between BP and risk factors in a multiracial, predominantly American Indian, school district.METHODS:A total of 1,829 American Indian, white, Hispanic, and African American students, 5-17 years old, were included in this study. The mean of two BP measurements, taken at the initial screening with an electronic BP monitor, were categorized as normal, prehypertensive, or hypertensive using the 2004 Fourth Report BP screening recommendations. Prevalence of prehypertensive and hypertensive BP measurements by race, gender, age, and body mass index (BMI) were determined, and their associations analyzed with logistic regression.RESULTS:The prevalence of prehypertensive measurements was 16.7% and prevalence of hypertensive measurements was 13.8% at first screen. Obesity was a risk factor for elevated BP for females and males (adjusted odds ratio (OR) = 4.01 and 4.33, respectively). Older age was also significantly associated with prehypertensive and hypertensive BP measurements, especially among males (adjusted OR = 6.91). Among females, American Indian race was protective against elevated BP (adjusted OR = 0.61).CONCLUSIONS:Obesity was consistently associated with an increased risk for elevated BP. American Indian race was associated with decreased risk of elevated BP measurements in females. The high prevalence of obesity-related hypertensive measurements in this population that includes American Indian children was similar to levels found in other multiracial populations of school children when using BP measurements from a single assessment.

Given the reported association of cardiac complications with hereditary hemochromatosis and the high carrier frequency of HFE gene mutations in the natural population, it seems reasonable that such mutations might appear more frequently than expected among symptomatic cardiac patients. Thus, H63D, C282Y, and S65C mutations and their possible associations were examined in 477 Caucasian males undergoing coronary angiography. Genotypes were analyzed for differences between ferritin and transferrin levels, coronary artery disease (CAD), cardiomyopathy (CM), and cardiovascular disease (CVD) mortality. No significant differences were found in ferritin levels between those with or without HFE mutations (C282Y P = 0.632, H63D P = 0.765, S65C P = 0.568, and HFE mutation P = 0.568); however, there was a significant difference (P = 0.005) in mean transferrin levels between those with (252 μg/l) and without (275 μg/l) C282Y. No relationship between HFE mutations and CAD (C282Y, P = 0.402; H63D, P = 0.112; S65C, P = 0.170) or CVD death (C282Y, P = 0.560; H63D, P = 0.682; S65C, P = 0.664) was demonstrated using logistic regression. However, an association between S65C and CM was found (odds ratio 4.4; 95% confidence interval 1.3–13.3, P = 0.018). This suggests that the S65C allele may contribute to the development of CM, but that these three HFE mutations do not appear to play a significant role in development of ischemic heart disease.

Objective: Data on Native American children and adolescents are rarely reported along with other racial and ethnic groups. The Healthy Kids Project is part of an effort to describe the prevalence of overweight and obesity in a racially mixed rural area where Native American, Hispanic, African American, and white children reside.Methods and Procedures: We measured height and weight of students in Anadarko, Oklahoma public schools (n = 1,980) in 2002-2003. All available students (95.7%) whose parents had not opted out of school health assessments were included. From these data, we calculated BMI (weight (kg)/height (m(2))) and used the International Obesity Task Force reference to classify children into BMI categories.Results: Native American, Hispanic, African American, and white children who live and attend school in the same surroundings are at risk of overweight and obesity. White children had the lowest combined prevalence of overweight and obesity (37.6%), and Native American children had the highest (53.8%) followed closely by African American (51.7%) and Hispanic children (50.5%).Discussion: The childhood obesity epidemic includes all racial and ethnic groups to different degrees. In a rural public school, Native American, Hispanic, and African children had higher rates of overweight/obesity than white children.

OBJECTIVE:A range of behavioral and psychosocial factors may contribute to a chronically stimulated hypothalamic-pituitary-adrenal (HPA) axis and subsequently altered diurnal patterns. The goal of this cross-sectional study was to examine associations among diurnal cortisol levels, perceived stress, and obesity patterns. METHODS:Seventy-eight women (aged 24-72 years) employed in a rural public school system completed the perceived stress scale, collected diurnal saliva samples, and underwent anthropometric assessments. Reduced peak-to-nadir cortisol values across the day were considered a sign of impairment in HPA function. A series of linear regression models determined the best predictors of diurnal cortisol variation. RESULTS:There was a marginal linear trend in stress levels across body mass index (BMI) categories, with obese women reporting the highest levels of stress (p = 0.07). Perceived stress was the only significant predictor of the degree of flattening of the diurnal cortisol curve in the sample as a whole (beta = -0.042, R(2) = 0.11, F = 8.6, p = 0.005), indicating reduction in the normal diurnal pattern. Among overweight women (BMI = 25-29.9 kg/m(2)), stress and waist circumference combined predicted 35% of the variability in diurnal cortisol. In contrast, among obese women (BMI > or = 30 kg/m(2)), BMI predicted 31% of the variability in diurnal cortisol (F = 13.8, p = 0.001), but stress was no longer significantly related to diurnal cortisol. CONCLUSIONS:Psychological stress predicts a significant portion of HPA axis functioning. In overweight women, perceived stress and waist circumference were of approximately equal importance in predicting adrenal cortisol secretion. However, among obese women, a major portion of the diurnal cortisol variation was predicted by BMI alone, not stress or waist circumference. This may help elucidate the mechanisms linking obesity to increased risk of cardiovascular disease (CVD).