Adverse health effects of low levels of perceived control in Swedish and Russian community samples

Background: This cross-sectional study of two middle-aged community samples from Sweden and Russia examined the distribution of perceived control scores in the two populations, investigated differences in individual control items between the populations, and assessed the association between perceived control and self-rated health. Methods: The samples consisted of men and women aged 45–69 years, randomly selected from national and local population registers in southeast Sweden (n = 1007) and in Novosibirsk, Russia (n = 9231). Data were collected by structured questionnaires and clinical measures at a visit to a clinic. The questionnaire covered socioeconomic and lifestyle factors, societal circumstances, and psychosocial measures. Self-rated health was assessed by standard single question with five possible answers, with a cut-off point at the top two alternatives. Results: 32.2 % of Swedish men and women reported good health, compared to 10.3 % of Russian men and women. Levels of perceived control were also significantly lower in Russia than in Sweden and varied by socio-demographic parameters in both populations. Sub-item analysis of the control questionnaire revealed substantial differences between the populations both in the perception of control over life and over health. Logistic regression analysis revealed that the odds ratios (OR) of poor self-rated health were significantly increased in men and women with low perceived control in both countries (OR between 2.61 and 4.26). Conclusion: Although the cross-sectional design does not allow causal inference, these results support the view that perceived control influences health, and that it may mediate the link between socioeconomic hardship and health

Growth status and menarcheal age among adolescent school girls in Wannune, Benue State, Nigeria

<p>Abstract</p> <p>Background</p> <p>Menarcheal age is a sensitive indicator of environmental conditions during childhood. The aim of study is to determine the age at menarche and growth status in adolescents in a rural area of Tarka, Wannune, Nigeria.</p> <p>Methods</p> <p>Data on 722 female students (aged 12-18 years) were collected in February 2009. Height and weight were measured. Body mass index (BMI; kg m^-2) was used as an index of relative weight.</p> <p>Results</p> <p>Mean and median menarcheal age calculated by probit analysis were 13.02 (SD 3.0) (95% CI: 13.02-13.07), and age 13.00 (SD 2.8) (95% CI: 12.98-13.04), respectively. Girls who reach menarche are significantly heavier and taller with higher BMIs than those of their pre-menarcheal peers.</p> <p>Conclusion</p> <p>The age of menarche is probably still declining in Nigeria. Although BMI is an important factor in the onset of menstruation, some other unmeasured environmental variables may be implicated in this population.</p

Elastic Properties of Novel Co- and CoNi-Based Superalloys Determined through Bayesian Inference and Resonant Ultrasound Spectroscopy

Bayesian inference is employed to precisely evaluate single crystal elastic properties of novel γ- γ′ Co- and CoNi-based superalloys from simple and non-destructive resonant ultrasound spectroscopy (RUS) measurements. Nine alloys from three Co-, CoNi-, and Ni-based alloy classes were evaluated in the fully aged condition, with one alloy per class also evaluated in the solution heat-treated condition. Comparisons are made between the elastic properties of the three alloy classes and among the alloys of a single class, with the following trends observed. A monotonic rise in the c44 (shear) elastic constant by a total of 12 pct is observed between the three alloy classes as Co is substituted for Ni. Elastic anisotropy (A) is also increased, with a large majority of the nearly 13 pct increase occurring after Co becomes the dominant constituent. Together the five CoNi alloys, with Co:Ni ratios from 1:1 to 1.5:1, exhibited remarkably similar properties with an average A 1.8 pct greater than the Ni-based alloy CMSX-4. Custom code demonstrating a substantial advance over previously reported methods for RUS inversion is also reported here for the first time. CmdStan-RUS is built upon the open-source probabilistic programing language of Stan and formulates the inverse problem using Bayesian methods. Bayesian posterior distributions are efficiently computed with Hamiltonian Monte Carlo (HMC), while initial parameterization is randomly generated from weakly informative prior distributions. Remarkably robust convergence behavior is demonstrated across multiple independent HMC chains in spite of initial parameterization often very far from actual parameter values. Experimental procedures are substantially simplified by allowing any arbitrary misorientation between the specimen and crystal axes, as elastic properties and misorientation are estimated simultaneously

Microstructural statistics for fatigue crack initiation in polycrystalline nickel-base superalloys

International audienceIn advanced engineering alloys where inclusions and pores are minimized during processing, the initiation of cracks due to cyclic loading shifts to intrinsic microstructural features. Criteria for the identification of crack initiation sites, defined using elastic-plastic loading parameters and twin boundary length, have been developed and applied to experimental datasets following cyclic loading. The criteria successfully quantify the incidence of experimentally observed cracks. Statistical microstructural volume elements are defined using a convergence approach for two nickel-base superalloys, IN100 and René 88DT. The material element that captures the fatigue crack-initiating features in René 88DT is smaller than IN100 due to a combination of smaller grain size and higher twin density

Tuning Strain Localization in Polycrystalline Nickel-Based Superalloys by Thermomechanical Processing

International audienc

Influência dos estágios de maturação sexual no estado nutricional, antropometria e composição corporal de adolescentes Influence of the stages of sexual maturation in the nutritional status, anthropometrics and corporal composition of adolescents

Os fenômenos puberais apresentam variabilidade no que diz respeito às idades de início e término, à velocidade e magnitude com que se expressam e as suas inter-relações. Tais fenômenos influenciam as modificações antropométricas e de composição corporal que caracterizam o processo de crescimento e desenvolvimento da adolescência. O artigo tem como objetivo analisar a influência dos estágios de maturação sexual, no estado nutricional, antropometria e composição corporal de adolescentes de ambos os sexos. A revisão de literatura foi realizada utilizando-se os termos "Adolescent, Puberty and Body Composition", por meio de consulta na base de dados do HighWire Press®. Trabalhou-se com artigos publicados desde janeiro de 1995 até julho de 2006, incluindo, outros relevantes ao tema, publicados anteriormente. Na adolescência, para se avaliar o estado nutricional e as modificações antropométricas e de composição corporal, é de extrema importância a consideração não somente da idade cronológica, mas também do estágio de maturação sexual. Cabe ressaltar as consideráveis dificuldades metodológicas existentes nos estudos acerca do estadiamento pubertário. Destaca-se a importância da realização de mais estudos, no sentido de elucidar a influência dos estágios de maturação sexual na evolução dos parâmetros antropométricos e de composição corporal, possibilitando a construção e utilização sistemática de referências que considerem o desenvolvimento pubertário.<br>Puberty phenomena concerning ages of onset and ending, speed and magnitude of expression, and interrelations are variable. Such phenomena influence anthropometric and body composition changes characterizing the process of growth and development during adolescence. This article has the objective of analyzing the influence of sexual maturing status on nutritional status, anthropometry and body composition in adolescents of both sexes. Literature review was accomplished through the use of the terms "Adolescent, Puberty and Body Composition" through consultation to the HighWire Press® database. Articles published from January 1995 to July 2006 were utilized, including others previously published and relevant to the subject. To assess nutritional status, anthropometric and body composition changes, during adolescence it is extremely important that consideration is not restricted to chronological age but extended to sexual maturity as well. The considerable methodological difficulties related to puberty staging should be emphasized. There is a need to accomplish further studies to clarify sexual maturing staging in anthropometric and body composition parameters, enabling systematic building and use of references considering puberty development