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Key message: A new powdery mildew resistance gene that can be readily used in wheat breeding, Pm65, was identified in the facultative wheat cultivar Xinmai 208 and mapped to the terminal region of chromosome 2AL. Wheat powdery mildew, a widely occurring disease caused by the biotrophic fungus Blumeriagraminis f. sp. tritici (Bgt), poses a serious threat to wheat production. A high breeding priority is to identify powdery mildew resistance genes that can be readily used either alone or in gene complexes involving other disease resistance genes. An F2 population and 227 F2:3 families derived from the cross Xinmai 208 × Stardust were generated to map a powdery mildew resistance gene in Xinmai 208, a high-yielding Chinese wheat cultivar. Genetic analysis indicated that Xinmai 208 carries a single dominant powdery mildew resistance gene, designated herein Pm65, and linkage analysis delimited Pm65 to a 0.5 cM interval covering 531.8 Kb (763,289,667–763,821,463 bp) on chromosome 2AL in the Chinese Spring reference sequence. An allelism test indicated that Pm65 is a new gene about 10.3 cM distal to the Pm4 locus. Pm65 was 0.3 cM proximal to Xstars355 and 0.2 cM distal to Xstars356. It conferred near-immunity to 19 of 20 Bgt isolates collected from different wheat-growing regions of the USA. Coming from a high-yield potential cultivar, Pm65 can be directly used to enhance powdery mildew resistance in wheat. The newly developed SSR markers Xstars355 and Xstars356 have the potential to tag Pm65 for wheat improvement. [ABSTRACT FROM AUTHOR]

Objectives: Short and long sleep duration are associated with poor health outcomes and are most prevalent among racial/ethnic minorities. Few studies have investigated the intersection of other sociodemographic characteristics with race/ethnicity on sleep duration prevalence., Design: Longitudinal retrospective analysis of continental U.S. cohort, the REasons for Geographic And Racial Differences in Stroke (REGARDS) PARTICIPANTS: Black (n = 7,547) and white (n = 12,341) adults, 56% women, ≥45 years MEASUREMENTS: At baseline (2003-07), participants reported age, sex, race, education, income, marital status, U.S. region, and employment status. The weighted average of reported sleep duration on weekdays and weekends, assessed at follow-up (2008-10), was categorized as <6, 6.0-6.99, 7.0-7.99 [reference], 8.0-8.99, and ≥9 h. Multinomial logistic regression models examined the independent and multivariable associations of sociodemographic factors with sleep duration. Interactions terms between race with education, income, region, and sex were examined., Results: Average sleep duration was 7.0 h (SD=1.3). Prevalence of short (<6 h) and long (≥9 h) sleep duration was 11.4% (n = 2,260) and 7.0% (n = 1,395), respectively. In the multivariable model, interactions terms race*income, race*sex, and race*region were significant (P < .05). Relative to white adults, black adults, were most likely to have short sleep duration. The magnitude of that likelihood increased across greater levels of household income, but with greatest odds among black adults living outside of the Southeast and Appalachian United States, particularly for men (≥$75k; black men OR = 5.47, 95%CI: 3.94,7.54; black women OR = 4.28, 95%CI: 3.08, 5.96)., Conclusions: Race in the context of socioeconomic, sex, and regional factors should be examined as key modifiers of sleep duration., (Copyright © 2020 National Sleep Foundation. All rights reserved.)

Background: High levels of obesity among African American women have been hypothesized to be partially resultant from a lower resting metabolic rate compared with white women. The aim of the current study was to determine if differences in cardiorespiratory fitness and moderate-to-vigorous physical activity are associated with differences in resting metabolic rate among free-living young adult African American women and white women., Methods: Participants were 179 women (white women n = 141, African American women n = 38, mean age = 27.7 years). Resting metabolic rate was measured using indirect calorimetry, body composition using dual energy x-ray absorptiometry, cardiorespiratory fitness via maximal treadmill test, and moderate-to-vigorous physical activity using an activity monitor., Results: African American women had higher body mass index, fat mass, and fat-free mass compared with white women but lower levels of cardiorespiratory fitness. No differences were observed between African American and white women in resting metabolic rate when expressed as kcal/day (1390.8 ± 197.5 vs 1375.7 ± 173.6 kcal/day, P = .64), but African American women had a lower resting metabolic rate when expressed relative to body weight (2.56 ± 0.30 vs 2.95 ± 0.33 mL/kg/min, P < .001). After statistical adjustment for differences in body composition between groups using linear regression models, African American women had a lower resting metabolic rate compared with white women (1299.4 ± 19.2 vs 1400.4 ± 9.2 kcal/day, P < .001). The addition of cardiorespiratory fitness reduced the differences among groups by 25%. The addition of moderate-to-vigorous physical activity did not improve the model., Conclusions: The present study confirms that African American women have a lower resting metabolic rate compared with their white peers, and low cardiorespiratory fitness explained 25% of this difference. Variables associated with resting metabolic rate, such as cardiorespiratory fitness, represent possible points of tailored interventions designed to address high levels of obesity seen in certain demographic groups., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: To validate the PAR protocol, a novel method for calculating population-level estimated energy requirements (EERs) and average physical activity ratio (APAR), in a nationally representative sample of US adults., Methods: Estimates of EER and APAR values were calculated via a factorial equation from a nationally representative sample of 2597 adults aged 20 and 74 years (US National Health and Nutrition Examination Survey; data collected between January 1, 2005, and December 31, 2006). Validation of the PAR protocol-derived EER (EER(PAR)) values was performed via comparison with values from the Institute of Medicine EER equations (EER(IOM))., Results: The correlation between EER(PAR) and EER(IOM) was high (0.98; P<.001). The difference between EER(PAR) and EER(IOM) values ranged from 40 kcal/d (1.2% higher than EER(IOM)) in obese (body mass index [BMI] ≥30) men to 148 kcal/d (5.7% higher) in obese women. The 2005-2006 EERs for the US population were 2940 kcal/d for men and 2275 kcal/d for women and ranged from 3230 kcal/d in obese (BMI ≥30) men to 2026 kcal/d in normal weight (BMI <25) women. There were significant inverse relationships between APAR and both obesity and age. For men and women, the APAR values were 1.53 and 1.52, respectively. Obese men and women had lower APAR values than normal weight individuals (P¼.023 and P¼.015, respectively) [corrected], and younger individuals had higher APAR values than older individuals (P<.001)., Conclusion: The PAR protocol is an accurate method for deriving nationally representative estimates of EER and APAR values. These descriptive data provide novel quantitative baseline values for future investigations into associations of physical activity and health., (Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Background: To examine the prevalence of television (TV) viewing, computer use, and their combination and associations with demographic characteristics and body mass index (BMI) among U.S. youth., Methods: The 1999 to 2006 National Health and Nutrition Examination Survey (NHANES) was used. Time spent yesterday sitting and watching television or videos (TV viewing) and using the computer or playing computer games (computer use) were assessed by questionnaire., Results: Prevalence (%) of meeting the U.S. objective for TV viewing (< or =2 hours/day) ranged from 65% to 71%. Prevalence of no computer use (0 hours/day) ranged from 23% to 45%. Non-Hispanic Black youth aged 2 to 15 years were less likely than their non-Hispanic White counterparts to meet the objective for TV viewing. Overweight or obese school-age youth were less likely than their normal weight counterparts to meet the objective for TV viewing., Conclusions: Computer use is prevalent among U.S. youth; more than half of youth used a computer on the previous day. The proportion of youth meeting the U.S. objective for TV viewing is less than the target of 75%. Time spent in sedentary behaviors such as viewing TV may contribute to overweight and obesity among U.S. youth.