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The purpose of this paper was to study the sex differences in infant mortality and mortality before the age of 5 in China, and the differences between urban and rural areas on the one hand and urban areas of mainland China and Hong Kong on the other. Published data from the 1982 and 1990 national censuses, the mortality survey of 1976, and UN's publications were used to calculate sex differences and sex ratios of mortality. Infant mortality of both sexes decreased notably from the 1970's onwards, the sex ratios of mortality being 1.15 in 1973–75, 1.06 in 1981 and 0.86 in 1990. A remarkable decline of mortality before the age of 5 was also seen in both sexes, but the sex ratios of mortality were not greatly altered, remaining less than 1 from the 1970's on. In rural areas female infants and young children had a higher mortality compared with males than in urban areas. In Hong Kong, the sex differences of infant and early child mortality were much smaller than in urban areas of mainland China.
Background: Dyslipidemia is a risk factor of type 2 diabetes (T2D). Women with a history of gestational diabetes (GDM) have a greater T2D risk; however, whether lipids patterns contribute to risk of progression remains unclear. Methods: We conducted a nested case-control study of incident T2D among women enrolled in the Nurses’ Health Study II reporting a history of GDM prior to the first blood collection (1995-1999) and followed-up through 2013. Plasma lipidomics containing 180 metabolites were measured in a subset of 175 incident cases and 176 age-matched controls by liquid chromatography-mass spectrometry. We constructed lipid networks using a weighted-correlation algorithm, and examined the association of individual lipids and sub-networks with T2D risk using logistic regression, adjusting for established T2D risk factors. Results: We identified 39 lipids species significantly associated with T2D risk (FDR<0.05), and observed different association patterns (in which associations were differed by numbers of carbon and double-bonds) across various lipid classes. We constructed 5 co-regulating lipid sub-networks, one of which (featuring the interactions between diacylglycerol, triacylglycerol, and phosphatidylethanolamine with mid-length carbon and less double-bonds) was significantly associated with incident T2D risk (odds ratio for increasing quartiles was 1 [reference], 2.4, 3.4, and 4.4; P-trend=0.0008). The addition of significant lipid species to a base model (13 traditional risk factors and medications) to predict incident T2D increased the c-statistics from 0.83 to 0.90 (P=0.001) with a corresponding categorical net reclassification index of 0.27 (P<0.001) in cross-validation. Conclusions: The dysregulation of certain lipid specie/class may contribute to a higher risk of incident T2D after a GDM pregnancy. Plasma lipid species and the network signatures may aid future clinical risk assessment and targeted interventions. Disclosure J. Li: None. L. Liang: None. F. Hu: None. C. Zhang: None. D. Tobias: None.
The loading parameter determining the stress and strain fields near a crack tip, and thereby the growth of the crack, under creep conditions is discussed. Relevant loading parameters considered are the stress intensity factor K/sub I/, the path-independent integral C*, and the net section stress sigma/sub net/. The material behavior is modelled as elastic-nonlinear viscous where the nonlinear term describes power law creep. At the time t = 0 load is applied to the cracked specimen, and in the first instant the stress distribution is elastic. Subsequently, creep deformation relaxes the initial stress concentration at the crack tip, and creep strains develop rapidly near the crack tip. These processes may be analytically described by self-similar solutions for short times t. Small scale yielding may be defined. In creep problems, this means that elastic strains dominate almost everywhere except in a small creep zone which grows around the crack tip. If crack growth ensues while the creep zone is still small compared with the crack length and the specimen size, the stress intensity factor governs crack growth behavior. If the calculated creep zone becomes larger than the specimen size, the stresses become finally time-independent and the elastic strain rates can be neglected. In this case, the stress field is the same as in the fully-plastic limit of power law hardening plasticity. The loading parameter which determines the near tip fields uniquely is then the path-independent integral C*.K/sub I/ and C* characterize opposite limiting cases. The case applied in a given situation is decided by comparing the creep zone size with the specimen size and the crack length. Besides several methods of estimating the creep zone size, a convenient expression for a characteristic time is derived, which characterizes the transition from small scale yielding to extensive creep of the whole specimen.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDetermination of enantiomeric purity using chiral lanthanide shift reagentsGeorge M. Whitesides and Daniel W. LewisCite this: J. Am. Chem. Soc. 1971, 93, 22, 5914–5916Publication Date (Print):November 1, 1971Publication History Published online1 May 2002Published inissue 1 November 1971https://pubs.acs.org/doi/10.1021/ja00751a066https://doi.org/10.1021/ja00751a066research-articleACS PublicationsRequest reuse permissionsArticle Views305Altmetric-Citations76LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Overweight and obesity have been prospectively associated with the risk of coronary heart disease (CHD). Less clear is the relation of excess weight to risk of CHD among men and women with comorbid conditions, and the proportion of CHD risk attributable to excess weight in the US population. To assess the risk of CHD associated with excess weight among men and women with and without associated comorbid conditions, and determine the population attributable risk of CHD associated with excess weight. The study population consisted of two prospective cohorts, the Health Professionals Follow‐up Study (HPFS) ( N = 42,351 men; age range at baseline, 39–75 years) and the Nurses' Health Study (NHS) ( N = 76,703 women; age range at baseline, 39–65 years). A total of 2,771 incident cases of CHD among the men and 2,359 among the women were documented over the 16 years of follow‐up. Overall, the relative risk (RR) of CHD associated with BMI ≥30 kg/m 2 compared with BMI 18.5–22.9 kg/m 2 was 2.13 (95% confidence interval (CI), 1.82–2.48) among the men and 2.48 (95% CI, 2.20–2.80) among the women. The risk of CHD increased with BMI, both with and without the presence of comorbid conditions. Our estimates suggest that more than a third of all incident CHD in US men and women may be attributed to excess weight. Excess weight is associated with increased risk of CHD among men and women, both alone and in combination with comorbid conditions, though the results require careful interpretation. A substantial proportion of incident CHD may be attributed to excess weight.
ABSTRACT Background Sudden cardiac death (SCD) accounts for ~300,000 deaths annually in the US. Men have a higher risk of SCD and are more likely to have underlying coronary artery disease (CAD) than women. In contrast, women are more likely to have arrhythmic events in the setting of inherited or acquired QT prolongation. Moreover, there is evidence of sex differences in the underlying genetics of QT interval duration. Using sex- and CAD-stratified analyses, we assess differences in genetic association between prolonged QT interval and SCD risk. Methods We examined 2,282 SCD subjects with autopsy-confirmed underlying disease from the Fingesture cohort and 3,561 Finnish controls. The SCD subjects were stratified by underlying disease (ischemic vs. non-ischemic) and by sex. We used logistic regression to test for association between the top QT interval associated SNP, rs12143842 (in the NOS1AP locus), and SCD risk. We also performed Mendelian randomization to test for causal association of QT interval in the various subgroups. Results Female SCD victims with underlying non-ischemic disease had the strongest association between rs12143842 and SCD risk (OR=1.37; 95% CI, 1.07-1.75) and the strongest causal association, established using Mendelian randomization, between prolonged QT interval and SCD (OR in SCD risk per SD increase in QT, 3.60; 95% CI, 1.22-10.49). Ischemic SCD victims, irrespective of sex, did not show an association between rs12143842 and SCD risk or a causal association for QT interval. Conclusions This study provides evidence that the causal effect of QT prolongation on SCD risk differs by sex and underlying disease.
Background: Studies of fruit and vegetable consumption in relation to overall health are limited. We evaluated the relationship between fruit and vegetable intake and the in-cidence of cardiovascular disease and cancer and of deaths from other causes in two prospective cohorts. Methods: A total of 71 910 female participants in the Nurses ’ Health study and 37 725 male participants in the Health Profession-als ’ Follow-up Study who were free of major chronic disease completed baseline semiquantitative food-frequency ques-tionnaires in 1984 and 1986, respectively. Dietary informa-tion was updated in 1986, 1990, and 1994 for women and in 1990 and 1994 for men. Participants were followed up for incidence of cardiovascular disease, cancer, or death
Deformation of an isolated void in an infinite block of linearly or nonlinearly viscous material is studied for remote axisymmetric stressing. The material is isotropic and incompressible with a power-law dependence of strain-rate on stress. Included in the family of materials are a linearly viscous solid and a rigid–perfectly plastic solid at the extreme limit of nonlinearity. Evolution of the void shape and size is analyzed in detail for voids starting as spheres in the linearly viscous material under all possible combinations of remote axisymmetric stressing. Asymptotic, or self-similar, shapes towards which the voids evolve are exhibited as are the associated rates of growth or collapse. Under conditions of high remote triaxial stressing the growth-rate of the asymptotic void is found to be identical to that of a spherical void with the same volume. The influence of nonlinearity on the growth-rate and deformation of a spherical void is investigated. Under high triaxiality conditions the behavior of a void in the nonlinearly viscous or rigid–perfectly plastic material is qualitatively different from that of a void in a linearly viscous material. In particular, a void in a nonlinear block undergoing tensile straining with sufficiently large superimposed remote hydrostatic tension grows more rapidly in directions perpendicular to the straining direction than along it and becomes significantly oblate. Asymptotic growth-rates are estimated numerically for the nonlinear materials. The results for the isolated void are used in a simple, approximate way to investigate the roles of material nonlinearity and stressing conditions on the strain required for ductile failure by void growth and coalescence.
Energy imbalance, obesity, and physical inactivity are key risk factors for at least eight types of cancer as well as other life-threatening conditions. Obesity results from an excess of energy intake relative to energy expenditure over time. Until recently, the onus for maintaining a healthy body weight was placed predominantly on the individual. The traditional concept of individual autonomy cannot explain the rapid worldwide increase in obesity and physical inactivity over the last 40 years. A new paradigm has emerged, in which individual choices are important, but these choices are made within a social, economic, and physical context that profoundly influences the options. Food choices are affected by the availability and pricing of different products and by social norms about eating patterns body weight. Urbanization and a more rapid pace of life reduce access to homegrown and home-cooked foods, and mechanization replaces the need for walking and manual labor.
