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Sample records for population odds ratio

  1. Measuring additive interaction using odds ratios

    PubMed Central

    Kalilani, Linda; Atashili, Julius

    2006-01-01

    Interaction measured on the additive scale has been argued to be better correlated with biologic interaction than when measured on the multiplicative scale. Measures of interaction on the additive scale have been developed using risk ratios. However, in studies that use odds ratios as the sole measure of effect, the calculation of these measures of additive interaction is usually performed by directly substituting odds ratios for risk ratios. Yet assessing additive interaction based on replacing risk ratios by odds ratios in formulas that were derived using the former may be erroneous. In this paper, we evaluate the extent to which three measures of additive interaction – the interaction contrast ratio (ICR), the attributable proportion due to interaction (AP), and the synergy index (S), estimated using odds ratios versus using risk ratios differ as the incidence of the outcome of interest increases in the source population and/or as the magnitude of interaction increases. Our analysis shows that the difference between the two depends on the measure of interaction used, the type of interaction present, and the baseline incidence of the outcome. Substituting odds ratios for risk ratios, when calculating measures of additive interaction, may result in misleading conclusions. Of the three measures, AP appears to be the most robust to this direct substitution. Formulas that use stratum specific odds and odds ratios to accurately calculate measures of additive interaction are presented. PMID:16620385

  2. Computing Power and Sample Size for Informational Odds Ratio

    PubMed Central

    Efird, Jimmy T.

    2013-01-01

    The informational odds ratio (IOR) measures the post-exposure odds divided by the pre-exposure odds (i.e., information gained after knowing exposure status). A desirable property of an adjusted ratio estimate is collapsibility, wherein the combined crude ratio will not change after adjusting for a variable that is not a confounder. Adjusted traditional odds ratios (TORs) are not collapsible. In contrast, Mantel-Haenszel adjusted IORs, analogous to relative risks (RRs) generally are collapsible. IORs are a useful measure of disease association in case-referent studies, especially when the disease is common in the exposed and/or unexposed groups. This paper outlines how to compute power and sample size in the simple case of unadjusted IORs. PMID:24157518

  3. Understanding relative risk, odds ratio, and related terms: as simple as it can get.

    PubMed

    Andrade, Chittaranjan

    2015-07-01

    Risk, and related measures of effect size (for categorical outcomes) such as relative risks and odds ratios, are frequently presented in research articles. Not all readers know how these statistics are derived and interpreted, nor are all readers aware of their strengths and limitations. This article examines several measures, including absolute risk, attributable risk, attributable risk percent, population attributable risk percent, relative risk, odds, odds ratio, and others. The concept and method of calculation are explained for each of these in simple terms and with the help of examples. The interpretation of each is presented in plain English rather than in technical language. Clinically useful notes are provided, wherever necessary. PMID:26231012

  4. Odds ratios of work related deaths in United States workers.

    PubMed Central

    Leigh, J P

    1988-01-01

    A new data set on job related mortality within 347 3 digit occupations is merged with two national probability samples of United States workers to assess which groups are in hazardous and which in safe jobs. Logistic regressions are fitted to the two samples and the following covariates are assumed to explain employment in a hazardous job: age, race, gender, schooling, region, and marital status. Results from both samples are remarkably similar. Odds ratios for non-whites versus whites are roughly 1.2/1; for high school dropouts versus people with some college education roughly 2.2/1; and for men versus women roughly 5.0/1. PMID:3348992

  5. Odds ratio analysis in women with endometrial cancer

    PubMed Central

    Żak, Ewa; Pięta, Beata

    2016-01-01

    Introduction Despite the progress in diagnosis and treatment of malignant tumours, the effects of treatment are insufficient. Reduction of the risk of cervical, ovarian, and endometrial cancer is possible by introducing preventative actions. Aim of the study The aim of the thesis is the analysis of selected risk factors that may affect the increase or decrease in the odds ratio of developing endometrial cancer. Material and methods The study was conducted among patients of the Gynaecology and Obstetrics Hospital of Poznań University of Medical Sciences in the years 2011-2013. The research included a total of 548 female respondents aged between 40 and 84 years. Women responded to questions assessing elements of lifestyle such as consumption of alcohol, smoking, and eating certain groups of foods. Results The respondents consuming fruits and vegetables several times a week have a reduced risk of odds ratio and the OR is 0.85; 95% CI: 0.18-4.09, compared to the women who rarely consume vegetables and fruits. Consumption of whole-wheat bread several times a week reduces the risk of developing the cancer, OR = 0.59; 95% CI: 0.14-2.47, compared to women not consuming wholegrain bread at all. Respondents who consumed red meat, such as veal, pork, and lamb in the amount of 101-200 g per day have an increased risk of developing the disease: OR = 2.16; 95% CI: 1.09-4.28, compared to women not consuming red meat at all. Conclusions A diet rich in fruit and vegetables, onions, garlic, whole grains, and beans should be introduced in order to reduce the risk of endometrial cancer. The consumption of red meat and white pasta should be reduced or even eliminated. PMID:27095953

  6. [Razón de posibilidades: a proposed translation of the term odds ratio].

    PubMed

    Tapia, J A; Nieto, F J

    1993-01-01

    In English, odds ratio is a basic epidemiological measure approximating the relative risk. Odds ratio has been translated into Spanish in several ways, which has produced great terminological confusion. On the other hand, the English word odds is often used in epidemiology or statistics English textbooks, alone or as part of other expressions, but always keeping a definite mathematical meaning, which calls for a similarly definite term in Spanish. We discuss several translations of odds ratio found in the literature and propose the Spanish word "posibilidades" as a translation of odds and "razón de posibilidades" as a translation of odds ratio. PMID:8342087

  7. Limits on Log Odds Ratios for Unidimensional Item Response Theory Models

    ERIC Educational Resources Information Center

    Haberman, Shelby J.; Holland, Paul W.; Sinharay, Sandip

    2007-01-01

    Bounds are established for log odds ratios (log cross-product ratios) involving pairs of items for item response models. First, expressions for bounds on log odds ratios are provided for one-dimensional item response models in general. Then, explicit bounds are obtained for the Rasch model and the two-parameter logistic (2PL) model. Results are…

  8. Informational Odds Ratio: A Useful Measure of Epidemiologic Association in Environment Exposure Studies

    PubMed Central

    Efird, Jimmy T.; Lea, Suzanne; Toland, Amanda; Phillips, Christopher J.

    2012-01-01

    The informational odds ratio (IOR) measures the post-exposure odds divided by the pre-exposure odds (ie, information gained after knowing exposure status). A desirable property of an adjusted ratio estimate is collapsibility (ie, the combined crude ratio will not change after adjusting for a variable that is not a confounder). Adjusted traditional odds ratios (TORs) are not collapsible. In contrast, Mantel-Haenszel adjusted IORs generally are collapsible. IORs are a useful measure of disease association in environmental case-referent studies, especially when the disease is common in the exposed and/or unexposed groups. PMID:22518087

  9. Isomer residual ratio of odd-odd isotope {sup 180}Ta in supernova nucleosynthsis

    SciTech Connect

    Hayakawa, Takehito; Kajino, Toshitaka; Chiba, Satoshi; Mathews, Grant

    2010-06-01

    The nucleosynthesis of {sup 180}Ta has remained an unsolved problem and as its origin many nucleosynthesis mechanisms have been proposed. This isotope has the unique feature that the naturally occurring abundance of {sup 180}Ta is actually a meta-stable isomer (half-life of >=10{sup 15} yr), while the ground state is a 1{sup +} unstable state which beta-decays with a half-life of only 8.15 hr. We have made a new time-dependent calculation of {sup 180}Ta meta-stable isomer residual ratio after supernova neutrino-induced reactions. This residual isomer ratio is crucial for understanding the production and survival of this naturally occurring rare isotope. We have constructed a new model under temperature evolution after type II supernova explosion. We include the explicit linking between the isomer and all known excited states and found that the residual ratio is insensitive to astrophysical parameters such as neutrino energy spectrum, explosion energy, decay time constant. We find that the explicit time evolution of the synthesis of {sup 180}Ta avoids the overproduction relative to {sup 138}La for a neutrino process neutrino temperature of 4 MeV.

  10. At Odds: Concerns Raised by Using Odds Ratios for Continuous or Common Dichotomous Outcomes in Research on Physical Activity and Obesity

    PubMed Central

    Lovasi, Gina S.; Underhill, Lindsay J.; Jack, Darby; Richards, Catherine; Weiss, Christopher; Rundle, Andrew

    2012-01-01

    Purpose Research on obesity and the built environment has often featured logistic regression and the corresponding parameter, the odds ratio. Use of odds ratios for common outcomes such obesity may unnecessarily hinder the validity, interpretation, and communication of research findings. Methods We identified three key issues raised by the use of odds ratios, illustrating them with data on walkability and body mass index from a study of 13,102 New York City residents. Results First, dichotomization of continuous measures such as body mass index discards theoretically relevant information, reduces statistical power, and amplifies measurement error. Second, odds ratios are systematically higher (further from the null) than prevalence ratios; this inflation is trivial for rare outcomes, but substantial for common outcomes like obesity. Third, odds ratios can lead to incorrect conclusions during tests of interactions. The odds ratio in a particular subgroup might higher simply because the outcome is more common (and the odds ratio inflated) compared with other subgroups. Conclusion Our recommendations are to take full advantage of continuous outcome data when feasible and to use prevalence ratios in place of odds ratios for common dichotomous outcomes. When odds ratios must be used, authors should document outcome prevalence across exposure groups. PMID:23002407

  11. Constant Latent Odds-Ratios Models and the Mantel-Haenszel Null Hypothesis

    ERIC Educational Resources Information Center

    Hessen, David J.

    2005-01-01

    In the present paper, a new family of item response theory (IRT) models for dichotomous item scores is proposed. Two basic assumptions define the most general model of this family. The first assumption is local independence of the item scores given a unidimensional latent trait. The second assumption is that the odds-ratios for all item-pairs are…

  12. An Odds Ratio Approach for Detecting DDF under the Nested Logit Modeling Framework

    ERIC Educational Resources Information Center

    Terzi, Ragip; Suh, Youngsuk

    2015-01-01

    An odds ratio approach (ORA) under the framework of a nested logit model was proposed for evaluating differential distractor functioning (DDF) in multiple-choice items and was compared with an existing ORA developed under the nominal response model. The performances of the two ORAs for detecting DDF were investigated through an extensive…

  13. Odds Ratio Product of Sleep EEG as a Continuous Measure of Sleep State

    PubMed Central

    Younes, Magdy; Ostrowski, Michele; Soiferman, Marc; Younes, Henry; Younes, Mark; Raneri, Jill; Hanly, Patrick

    2015-01-01

    Study Objectives: To develop and validate an algorithm that provides a continuous estimate of sleep depth from the electroencephalogram (EEG). Design: Retrospective analysis of polysomnograms. Setting: Research laboratory. Participants: 114 patients who underwent clinical polysomnography in sleep centers at the University of Manitoba (n = 58) and the University of Calgary (n = 56). Interventions: None. Measurements and Results: Power spectrum of EEG was determined in 3-second epochs and divided into delta, theta, alpha-sigma, and beta frequency bands. The range of powers in each band was divided into 10 aliquots. EEG patterns were assigned a 4-digit number that reflects the relative power in the 4 frequency ranges (10,000 possible patterns). Probability of each pattern occurring in 30-s epochs staged awake was determined, resulting in a continuous probability value from 0% to 100%. This was divided by 40 (% of epochs staged awake) producing the odds ratio product (ORP), with a range of 0–2.5. In validation testing, average ORP decreased progressively as EEG progressed from wakefulness (2.19 ± 0.29) to stage N3 (0.13 ± 0.05). ORP < 1.0 predicted sleep and ORP > 2.0 predicted wakefulness in > 95% of 30-s epochs. Epochs with intermediate ORP occurred in unstable sleep with a high arousal index (> 70/h) and were subject to much interrater scoring variability. There was an excellent correlation (r2 = 0.98) between ORP in current 30-s epochs and the likelihood of arousal or awakening occurring in the next 30-s epoch. Conclusions: Our results support the use of the odds ratio product (ORP) as a continuous measure of sleep depth. Citation: Younes M, Ostrowski M, Soiferman M, Younes H, Younes M, Raneri J, Hanly P. Odds ratio product of sleep EEG as a continuous measure of sleep state. SLEEP 2015;38(4):641–654. PMID:25348125

  14. Multiple Imputation for Missing Values Through Conditional Semiparametric Odds Ratio Models

    PubMed Central

    Chen, Hua Yun; Xie, Hui; Qian, Yi

    2010-01-01

    Summary Multiple imputation is a practically useful approach to handling incompletely observed data in statistical analysis. Parameter estimation and inference based on imputed full data have been made easy by Rubin's rule for result combination. However, creating proper imputation that accommodates flexible models for statistical analysis in practice can be very challenging. We propose an imputation framework that uses conditional semiparametric odds ratio models to impute the missing values. The proposed imputation framework is more flexible and robust than the imputation approach based on the normal model. It is a compatible framework in comparison to the approach based on fully conditionally specified models. The proposed algorithms for multiple imputation through the Monte Carlo Markov Chain sampling approach can be straightforwardly carried out. Simulation studies demonstrate that the proposed approach performs better than existing, commonly used imputation approaches. The proposed approach is applied to imputing missing values in bone fracture data. PMID:21210771

  15. Interpretation of Genetic Association Studies: Markers with Replicated Highly Significant Odds Ratios May Be Poor Classifiers

    PubMed Central

    Jakobsdottir, Johanna; Gorin, Michael B.; Conley, Yvette P.; Ferrell, Robert E.; Weeks, Daniel E.

    2009-01-01

    Recent successful discoveries of potentially causal single nucleotide polymorphisms (SNPs) for complex diseases hold great promise, and commercialization of genomics in personalized medicine has already begun. The hope is that genetic testing will benefit patients and their families, and encourage positive lifestyle changes and guide clinical decisions. However, for many complex diseases, it is arguable whether the era of genomics in personalized medicine is here yet. We focus on the clinical validity of genetic testing with an emphasis on two popular statistical methods for evaluating markers. The two methods, logistic regression and receiver operating characteristic (ROC) curve analysis, are applied to our age-related macular degeneration dataset. By using an additive model of the CFH, LOC387715, and C2 variants, the odds ratios are 2.9, 3.4, and 0.4, with p-values of 10−13, 10−13, and 10−3, respectively. The area under the ROC curve (AUC) is 0.79, but assuming prevalences of 15%, 5.5%, and 1.5% (which are realistic for age groups 80 y, 65 y, and 40 y and older, respectively), only 30%, 12%, and 3% of the group classified as high risk are cases. Additionally, we present examples for four other diseases for which strongly associated variants have been discovered. In type 2 diabetes, our classification model of 12 SNPs has an AUC of only 0.64, and two SNPs achieve an AUC of only 0.56 for prostate cancer. Nine SNPs were not sufficient to improve the discrimination power over that of nongenetic predictors for risk of cardiovascular events. Finally, in Crohn's disease, a model of five SNPs, one with a quite low odds ratio of 0.26, has an AUC of only 0.66. Our analyses and examples show that strong association, although very valuable for establishing etiological hypotheses, does not guarantee effective discrimination between cases and controls. The scientific community should be cautious to avoid overstating the value of association findings in terms of

  16. Sustainable sex ratio in lattice populations

    NASA Astrophysics Data System (ADS)

    Tainaka, K.; Hayashi, T.; Yoshimura, J.

    2006-05-01

    We present a lattice model of mating populations. Simulation is performed by two different methods: local and global interactions. Simulation results account for the reason why the observed sex ratio is nearly one half in many animals. The male-biased sex ratio, such as in human populations, is also explained.

  17. Analysis of familial aggregation of atopic eczema and other atopic diseases by ODDS RATIO regression models.

    PubMed

    Diepgen, T L; Blettner, M

    1996-05-01

    In order to determine the relative importance of genetics and the environment on the occurrence of atopic diseases, we investigated the familial aggregation of atopic eczema, allergic rhinitis, and allergic asthma in the relatives of 426 patients with atopic eczema and 628 subjects with no history of eczema (5,136 family members in total). Analyses were performed by regression models for odds ratios (OR) allowing us to estimate OR for the familial aggregation and simultaneously to adjust for other covariates. Three models were analyzed assuming that the OR i) is the same among any two members of a family, ii) depends on different familial constellations, i.e., whether the pairs are siblings, parents, or parent/sibling pairs, and iii) is not the same between the father and the children and between the mother and the children. The OR of familial aggregation for atopic eczema was 2.16 (95% confidence interval (95%-CI) 1.58-2.96) if no distinction was made between the degree of relationship. Further analyses within the members of the family showed a high OR among siblings (OR = 3.86; 95%-CI 2.10-7.09), while the OR between parents and siblings was only 1.90 (95%-CI 1.31-2.97). Only for atopic eczema was the familial aggregation between fathers and siblings (ms: OR = 2.66; fs: OR = 1.29). This can be explained by stronger maternal heritability, shared physical environment of mother and child, or environmental events that affect the fetus in utero. Since for all atopic diseases a stronger correlation was found between siblings than between siblings and parents, our study indicates that environmental factors, especially during childhood, seem to explain the recently observed increased frequencies of atopic diseases. PMID:8618061

  18. The Overall Odds Ratio as an Intuitive Effect Size Index for Multiple Logistic Regression: Examination of Further Refinements

    ERIC Educational Resources Information Center

    Le, Huy; Marcus, Justin

    2012-01-01

    This study used Monte Carlo simulation to examine the properties of the overall odds ratio (OOR), which was recently introduced as an index for overall effect size in multiple logistic regression. It was found that the OOR was relatively independent of study base rate and performed better than most commonly used R-square analogs in indexing model…

  19. Regional and neighborhood disparities in the odds of type 2 diabetes: results from 5 population-based studies in Germany (DIAB-CORE consortium).

    PubMed

    Müller, Grit; Kluttig, Alexander; Greiser, Karin Halina; Moebus, Susanne; Slomiany, Uta; Schipf, Sabine; Völzke, Henry; Maier, Werner; Meisinger, Christa; Tamayo, Teresa; Rathmann, Wolfgang; Berger, Klaus

    2013-07-15

    The objective of this study was to investigate the association between residential environment and type 2 diabetes. We pooled cross-sectional data from 5 population-based German studies (1997-2006): the Cardiovascular Disease, Living and Ageing in Halle Study, the Dortmund Health Study, the Heinz Nixdorf Recall Study, the Cooperative Health Research in the Region of Augsburg Study, and the Study of Health in Pomerania. The outcome of interest was the presence of self-reported type 2 diabetes. We conducted mixed logistic regression models in a hierarchical data set with 8,879 individuals aged 45-74 years on level 1; 226 neighborhoods on level 2; and 5 study regions on level 3. The analyses were adjusted for age, sex, social class, and employment status. The odds ratio for type 2 diabetes was highest in eastern Germany (odds ratio = 1.98, 95% confidence interval: 1.81, 2.14) and northeastern Germany (odds ratio = 1.58, 95% confidence interval: 1.40, 1.77) and lowest in southern Germany (reference) after adjustment for individual variables. Neighborhood unemployment rates explained a large proportion of regional differences. Individuals residing in neighborhoods with high unemployment rates had elevated odds of type 2 diabetes (odds ratio = 1.62, 95% confidence interval: 1.25, 2.09). The diverging levels of unemployment in neighborhoods and regions are an independent source of disparities in type 2 diabetes. PMID:23648804

  20. Element abundance ratios in stellar population modelling

    NASA Astrophysics Data System (ADS)

    Thomas, Daniel

    2015-04-01

    I review the implementation of the effects from varying chemical element abundance ratios in stellar population modelling, focusing on α- and Fe-peak elements. A brief overview of the development of such models over the past 30 years is provided, starting with early work on the identification of relevant absorption features in the spectra of early-type galaxies in the 1980s leading to the most recent developments of the past years. Recent highlights include the adoption of new flux calibrated libraries, the inclusion of a wide range of chemical elements, the calculation of error estimates on the model, and the consideration of element variation effects on full spectra. The calibration of such models with globular clusters and some key results on the element ratios measured in early-type galaxies are presented.

  1. Technical note: The risk ratio, an alternative to the odds ratio for estimating the association between multiple risk factors and a dichotomous outcome.

    PubMed

    Ospina, P A; Nydam, D V; DiCiccio, T J

    2012-05-01

    The objectives were (1) to explain why the risk ratio (RR) is an appropriate measure of association when the outcome of interest is dichotomous (e.g., displaced abomasum or no displaced abomasum) in both cohort studies and randomized trials; and (2) to outline an applied method for estimating the RR using currently available software. Interest in the association between multiple risk factors and a yes or no outcome is very common in the dairy industry; historically, logistic regression, which reports odds ratios (OR), was the method available in common statistical packages to evaluate this kind of association. However, the OR can overestimate the magnitude of the response in cohort studies and randomized trials when the outcome frequency is large. In addition, the interpretation of odds is not intuitive; fortunately, recent advances in statistical software have allowed the estimation of the RR. Because SAS software (SAS Institute Inc., Cary, NC) is commonly used to analyze data, this technical note outlines the basic programming code that may be used to estimate the RR from raw data. Example data from a prospective cohort study was used to compare the OR and RR of developing a displaced abomasum or ketosis or metritis based on multiple predictors, their interaction, and a random effect (e.g., herd). PMID:22541486

  2. A note on the use of the generalized odds ratio in meta-analysis of association studies involving bi- and tri-allelic polymorphisms

    PubMed Central

    2011-01-01

    Background The generalized odds ratio (GOR) was recently suggested as a genetic model-free measure for association studies. However, its properties were not extensively investigated. We used Monte Carlo simulations to investigate type-I error rates, power and bias in both effect size and between-study variance estimates of meta-analyses using the GOR as a summary effect, and compared these results to those obtained by usual approaches of model specification. We further applied the GOR in a real meta-analysis of three genome-wide association studies in Alzheimer's disease. Findings For bi-allelic polymorphisms, the GOR performs virtually identical to a standard multiplicative model of analysis (e.g. per-allele odds ratio) for variants acting multiplicatively, but augments slightly the power to detect variants with a dominant mode of action, while reducing the probability to detect recessive variants. Although there were differences among the GOR and usual approaches in terms of bias and type-I error rates, both simulation- and real data-based results provided little indication that these differences will be substantial in practice for meta-analyses involving bi-allelic polymorphisms. However, the use of the GOR may be slightly more powerful for the synthesis of data from tri-allelic variants, particularly when susceptibility alleles are less common in the populations (≤10%). This gain in power may depend on knowledge of the direction of the effects. Conclusions For the synthesis of data from bi-allelic variants, the GOR may be regarded as a multiplicative-like model of analysis. The use of the GOR may be slightly more powerful in the tri-allelic case, particularly when susceptibility alleles are less common in the populations. PMID:21645382

  3. The association in a two-way contingency table through log odds ratio analysis: the case of Sarno river pollution.

    PubMed

    Camminatiello, Ida; D'Ambra, Antonello; Sarnacchiaro, Pasquale

    2014-01-01

    In this paper we are proposing a general framework for the analysis of the complete set of log Odds Ratios (ORs) generated by a two-way contingency table. Starting from the RC (M) association model and hypothesizing a Poisson distribution for the counts of the two-way contingency table we are obtaining the weighted Log Ratio Analysis that we are extending to the study of log ORs. Particularly we are obtaining an indirect representation of the log ORs and some synthesis measures. Then for studying the matrix of log ORs we are performing a generalized Singular Value Decomposition that allows us to obtain a direct representation of log ORs. We also expect to get summary measures of association too. We have considered the matrix of complete set of ORs, because, it is linked to the two-way contingency table in terms of variance and it allows us to represent all the ORs on a factorial plan. Finally, a two-way contingency table, which crosses pollution of the Sarno river and sampling points, is to be analyzed to illustrate the proposed framework. PMID:25126485

  4. Likelihood ratio and score tests to test the non-inferiority (or equivalence) of the odds ratio in a crossover study with binary outcomes.

    PubMed

    Li, Xiaochun; Li, Huilin; Jin, Man; D Goldberg, Judith

    2016-09-10

    We consider the non-inferiority (or equivalence) test of the odds ratio (OR) in a crossover study with binary outcomes to evaluate the treatment effects of two drugs. To solve this problem, Lui and Chang (2011) proposed both an asymptotic method and a conditional method based on a random effects logit model. Kenward and Jones (1987) proposed a likelihood ratio test (LRTM ) based on a log linear model. These existing methods are all subject to model misspecification. In this paper, we propose a likelihood ratio test (LRT) and a score test that are independent of model specification. Monte Carlo simulation studies show that, in scenarios considered in this paper, both the LRT and the score test have higher power than the asymptotic and conditional methods for the non-inferiority test; the LRT, score, and asymptotic methods have similar power, and they all have higher power than the conditional method for the equivalence test. When data can be well described by a log linear model, the LRTM has the highest power among all the five methods (LRTM , LRT, score, asymptotic, and conditional) for both non-inferiority and equivalence tests. However, in scenarios for which a log linear model does not describe the data well, the LRTM has the lowest power for the non-inferiority test and has inflated type I error rates for the equivalence test. We provide an example from a clinical trial that illustrates our methods. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27095359

  5. Inferences about ungulate population dynamics derived from age ratios

    USGS Publications Warehouse

    Harris, N.C.; Kauffman, M.J.; Mills, L.S.

    2008-01-01

    Age ratios (e.g., calf:cow for elk and fawn:doe for deer) are used regularly to monitor ungulate populations. However, it remains unclear what inferences are appropriate from this index because multiple vital rate changes can influence the observed ratio. We used modeling based on elk (Cervus elaphus) life-history to evaluate both how age ratios are influenced by stage-specific fecundity and survival and how well age ratios track population dynamics. Although all vital rates have the potential to influence calf:adult female ratios (i.e., calf:xow ratios), calf survival explained the vast majority of variation in calf:adult female ratios due to its temporal variation compared to other vital rates. Calf:adult female ratios were positively correlated with population growth rate (??) and often successfully indicated population trajectories. However, calf:adult female ratios performed poorly at detecting imposed declines in calf survival, suggesting that only the most severe declines would be rapidly detected. Our analyses clarify that managers can use accurate, unbiased age ratios to monitor arguably the most important components contributing to sustainable ungulate populations, survival rate of young and ??. However, age ratios are not useful for detecting gradual declines in survival of young or making inferences about fecundity or adult survival in ungulate populations. Therefore, age ratios coupled with independent estimates of population growth or population size are necessary to monitor ungulate population demography and dynamics closely through time.

  6. Binary Logistic Regression Analysis for Detecting Differential Item Functioning: Effectiveness of R[superscript 2] and Delta Log Odds Ratio Effect Size Measures

    ERIC Educational Resources Information Center

    Hidalgo, Mª Dolores; Gómez-Benito, Juana; Zumbo, Bruno D.

    2014-01-01

    The authors analyze the effectiveness of the R[superscript 2] and delta log odds ratio effect size measures when using logistic regression analysis to detect differential item functioning (DIF) in dichotomous items. A simulation study was carried out, and the Type I error rate and power estimates under conditions in which only statistical testing…

  7. The Effects of Small Sample Size on Identifying Polytomous DIF Using the Liu-Agresti Estimator of the Cumulative Common Odds Ratio

    ERIC Educational Resources Information Center

    Carvajal, Jorge; Skorupski, William P.

    2010-01-01

    This study is an evaluation of the behavior of the Liu-Agresti estimator of the cumulative common odds ratio when identifying differential item functioning (DIF) with polytomously scored test items using small samples. The Liu-Agresti estimator has been proposed by Penfield and Algina as a promising approach for the study of polytomous DIF but no…

  8. An Analytical Evaluation of Two Common-Odds Ratios as Population Indicators of DIF.

    ERIC Educational Resources Information Center

    Pommerich, Mary; And Others

    The Mantel-Haenszel (MH) statistic for identifying differential item functioning (DIF) commonly conditions on the observed test score as a surrogate for conditioning on latent ability. When the comparison group distributions are not completely overlapping (i.e., are incongruent), the observed score represents different levels of latent ability…

  9. Does marital status predict the odds of suicidal death in taiwan? A seven-year population-based study.

    PubMed

    Yeh, Jui-Yuan; Xirasagar, Sudha; Liu, Tsai-Ching; Li, Chong-Yi; Lin, Herng-Ching

    2008-06-01

    Using nationwide, 7-year population-based data for 1997-2003, we examined marital status to see if it predicted suicide among the ethnic Chinese population of Taiwan. Using cause of death data, with a case-control design, two groups-total adult suicide deaths, n = 17,850, the study group, and adult deaths other than suicide, n = 71,400 (randomly selected from age, sex, and geographic region matched controls, four per suicide)-were studied. Using multiple logistic regression analysis including age-marital status interaction, adjusted estimates show divorced status to be the most detrimental for suicide propensity, with males showing stronger effect size. Females never married, aged below 35 and 65-plus, and widowed 65-plus had lower suicide odds. PMID:18611128

  10. Implications of a high population 2 B/Be ratio

    NASA Technical Reports Server (NTRS)

    Fields, Brian D.; Olive, Keith A.; Schramm, David N.

    1995-01-01

    The observed boron/beryllium ratio in extreme Population II stars has been interpreted as evidence of Be and B synthesis by early Galactic cosmic rays. However, a recent reanalysis of the boron abundance in the Population II halo star HD 140823 suggests that B/H may be larger than previously reported, by as much as a factor of 4. This would yield a B/Be ratio lying in the range 14 less than or approximately equal to B/Be less than or approximately equal to 50. The possibilty of a high Population II B/Be ratio stresses the importance of the upper limit to the B/Be ratio arising from cosmic-ray production. It is found that the limit to cosmic-ray-produced B/Be depends upon the assumed cosmic-ray spectrum. For any Population II cosmic-ray spectrum that is a single power law in either total energy per nucleon or in momentum, the B/Be ratio constrained to lie in the range 7.6 less than or approximately equal to B/Be less than or approximately equal to 14. Thus, if the new B/Be ratio is correct, it requires either a bimodal cosmic-ray flux with a large low-energy component, or, for another B source, possibly the proposed nu-process in supernovae, either of which may be helpful in explaining the observed B-11/B-10 ratio. Finally, it is noted that the boron reanalysis highlights the uncertainty in our knowledge of the B/Be ratio, and the need for additional data on Be and B abundances.

  11. Association of Serum Magnesium Level with Odds of Prediabetes and Diabetes in a Southern Chinese Population: a Prospective Nested Case-Control Study.

    PubMed

    Fang, Chenchen; Wang, Xuebao; Wu, Wenjun; Gu, Xuejiang; Ye, Tingting; Deng, Huihui; Wang, Xianqin; Shen, Feixia

    2016-08-01

    Although emerging clinical evidence supports that magnesium deficiency is a risk factor for the development of type 2 diabetes, there are sparse studies concerning the dynamic change of serum magnesium with the risk of diabetes and its early stages. In this nested case-control study, we performed a 75-g oral glucose tolerance test or a standardized steamed bread meal test in 178 subjects with incident glucose metabolism impairment (33 with type 2 diabetes and 145 with prediabetes) and 178 matched controls at baseline and at 3-year follow-up and determined the associations between baseline serum magnesium levels as well as changes in serum magnesium levels at follow-up and odds of prediabetes and diabetes. After adjusting for potential confounders, the odds ratios of risk for prediabetes and type 2 diabetes in the highest quartile of serum magnesium levels were 0.22 (95 % confidence intervals [CI] 0.10-0.49; p for trend <0.001) and 0.02 (95 % CI 0.00-0.29; p for trend = 0.009), respectively, as compared with the lowest quartile. In addition, a significant decline in the serum magnesium level was detected in type 2 diabetes cases (p = 0.015) at 3 years as compared with at baseline. These results suggest that a low magnesium level is an independent risk factor for prediabetes and type 2 diabetes, and that the reduction of serum magnesium is associated with type 2 diabetes in a southern Chinese population. PMID:26706038

  12. Suburbanization, estrogen contamination, and sex ratio in wild amphibian populations.

    PubMed

    Lambert, Max R; Giller, Geoffrey S J; Barber, Larry B; Fitzgerald, Kevin C; Skelly, David K

    2015-09-22

    Research on endocrine disruption in frog populations, such as shifts in sex ratios and feminization of males, has predominantly focused on agricultural pesticides. Recent evidence suggests that suburban landscapes harbor amphibian populations exhibiting similar levels of endocrine disruption; however the endocrine disrupting chemical (EDC) sources are unknown. Here, we show that sex ratios of metamorphosing frogs become increasingly female-dominated along a suburbanization gradient. We further show that suburban ponds are frequently contaminated by the classical estrogen estrone and a variety of EDCs produced by plants (phytoestrogens), and that the diversity of organic EDCs is correlated with the extent of developed land use and cultivated lawn and gardens around a pond. Our work also raises the possibility that trace-element contamination associated with human land use around suburban ponds may be contributing to the estrogenic load within suburban freshwaters and constitutes another source of estrogenic exposure for wildlife. These data suggest novel, unexplored pathways of EDC contamination in human-altered environments. In particular, we propose that vegetation changes associated with suburban neighborhoods (e.g., from forests to lawns and ornamental plants) increase the distribution of phytoestrogens in surface waters. The result of frog sex ratios varying as a function of human land use implicates a role for environmental modulation of sexual differentiation in amphibians, which are assumed to only have genetic sex determination. Overall, we show that endocrine disruption is widespread in suburban frog populations and that the causes are likely diverse. PMID:26372955

  13. Suburbanization, estrogen contamination, and sex ratio in wild amphibian populations

    PubMed Central

    Lambert, Max R.; Giller, Geoffrey S. J.; Barber, Larry B.; Fitzgerald, Kevin C.; Skelly, David K.

    2015-01-01

    Research on endocrine disruption in frog populations, such as shifts in sex ratios and feminization of males, has predominantly focused on agricultural pesticides. Recent evidence suggests that suburban landscapes harbor amphibian populations exhibiting similar levels of endocrine disruption; however the endocrine disrupting chemical (EDC) sources are unknown. Here, we show that sex ratios of metamorphosing frogs become increasingly female-dominated along a suburbanization gradient. We further show that suburban ponds are frequently contaminated by the classical estrogen estrone and a variety of EDCs produced by plants (phytoestrogens), and that the diversity of organic EDCs is correlated with the extent of developed land use and cultivated lawn and gardens around a pond. Our work also raises the possibility that trace-element contamination associated with human land use around suburban ponds may be contributing to the estrogenic load within suburban freshwaters and constitutes another source of estrogenic exposure for wildlife. These data suggest novel, unexplored pathways of EDC contamination in human-altered environments. In particular, we propose that vegetation changes associated with suburban neighborhoods (e.g., from forests to lawns and ornamental plants) increase the distribution of phytoestrogens in surface waters. The result of frog sex ratios varying as a function of human land use implicates a role for environmental modulation of sexual differentiation in amphibians, which are assumed to only have genetic sex determination. Overall, we show that endocrine disruption is widespread in suburban frog populations and that the causes are likely diverse. PMID:26372955

  14. Sex ratio bias, male aggression, and population collapse in lizards.

    PubMed

    Le Galliard, Jean-François; Fitze, Patrick S; Ferrière, Régis; Clobert, Jean

    2005-12-13

    The adult sex ratio (ASR) is a key parameter of the demography of human and other animal populations, yet the causes of variation in ASR, how individuals respond to this variation, and how their response feeds back into population dynamics remain poorly understood. A prevalent hypothesis is that ASR is regulated by intrasexual competition, which would cause more mortality or emigration in the sex of increasing frequency. Our experimental manipulation of populations of the common lizard (Lacerta vivipara) shows the opposite effect. Male mortality and emigration are not higher under male-biased ASR. Rather, an excess of adult males begets aggression toward adult females, whose survival and fecundity drop, along with their emigration rate. The ensuing prediction that adult male skew should be amplified and total population size should decline is supported by long-term data. Numerical projections show that this amplifying effect causes a major risk of population extinction. In general, such an "evolutionary trap" toward extinction threatens populations in which there is a substantial mating cost for females, and environmental changes or management practices skew the ASR toward males. PMID:16322105

  15. Abnormal sex ratios in human populations: Causes and consequences

    PubMed Central

    Hesketh, Therese; Xing, Zhu Wei

    2006-01-01

    In the absence of manipulation, both the sex ratio at birth and the population sex ratio are remarkably constant in human populations. Small alterations do occur naturally; for example, a small excess of male births has been reported to occur during and after war. The tradition of son preference, however, has distorted these natural sex ratios in large parts of Asia and North Africa. This son preference is manifest in sex-selective abortion and in discrimination in care practices for girls, both of which lead to higher female mortality. Differential gender mortality has been a documented problem for decades and led to reports in the early 1990s of 100 million “missing women” across the developing world. Since that time, improved health care and conditions for women have resulted in reductions in female mortality, but these advances have now been offset by a huge increase in the use of sex-selective abortion, which became available in the mid-1980s. Largely as a result of this practice, there are now an estimated 80 million missing females in India and China alone. The large cohorts of “surplus” males now reaching adulthood are predominantly of low socioeconomic class, and concerns have been expressed that their lack of marriageability, and consequent marginalization in society, may lead to antisocial behavior and violence, threatening societal stability and security. Measures to reduce sex selection must include strict enforcement of existing legislation, the ensuring of equal rights for women, and public awareness campaigns about the dangers of gender imbalance. PMID:16938885

  16. Multipole mixing ratios and substate populations in Rn-219

    NASA Astrophysics Data System (ADS)

    Jones, G. D.

    2016-08-01

    Historical alpha-gamma angular correlation data for the decay of 223Ra into excited states of 219Rn have been analysed, using the correct spins of the states involved, for the first time. The analyses produced multipole mixing ratios (E2/M1) of δ (144)=-0.11\\+/- 0.03, δ (154)=0, δ (158)=-0.205\\+/- 0.018 and δ (269)=-0.149\\+/- 0.004 where the nominal transition energies, in keV, are given in brackets. These values are consistent with published values obtained from internal conversion electron spectroscopy. It is also found that δ (324)=0 and δ (338)=-0.235\\+/- 0.030 (where both values differ from current tabulations) and that the sign of the multipole mixing ratio for the 122 keV transition is negative. The 158, 269 and 338 keV states are found to be aligned with high population of M=+/- 3/2 substates and the 127 keV state is believed to have undergone spin relaxation.

  17. Effective case/infection ratio of poliomyelitis in vaccinated populations.

    PubMed

    Bencskó, G; Ferenci, T

    2016-07-01

    Recent polio outbreaks in Syria and Ukraine, and isolation of poliovirus from asymptomatic carriers in Israel have raised concerns that polio might endanger Europe. We devised a model to calculate the time needed to detect the first case should the disease be imported into Europe, taking the effect of vaccine coverage - both from inactivated and oral polio vaccines, also considering their differences - on the length of silent transmission into account by deriving an 'effective' case/infection ratio that is applicable for vaccinated populations. Using vaccine coverage data and the newly developed model, the relationship between this ratio and vaccine coverage is derived theoretically and is also numerically determined for European countries. This shows that unnoticed transmission is longer for countries with higher vaccine coverage and a higher proportion of IPV-vaccinated individuals among those vaccinated. Assuming borderline transmission (R = 1·1), the expected time to detect the first case is between 326 days and 512 days in different countries, with the number of infected individuals between 235 and 1439. Imperfect surveillance further increases these numbers, especially the number of infected until detection. While longer silent transmission does not increase the number of clinical diseases, it can make the application of traditional outbreak response methods more complicated, among others. PMID:26830060

  18. The Pharmacy-Level Asthma Medication Ratio and Population Health

    PubMed Central

    Bradley, Courtney L.; Huang, Bin; Simmons, Jeffrey M.; Heaton, Pamela C.; Kahn, Robert S.

    2015-01-01

    BACKGROUND AND OBJECTIVES: Community pharmacies may be positioned for an increased role in population health. We sought to develop a population-level measure of asthma medication fills and assess its relationship to asthma-related utilization. METHODS: We conducted a retrospective, ecological study (2010–2012). Medication data from a chain of pharmacies (n = 27) within 1 county were used to calculate a Pharmacy-level Asthma Medication Ratio (Ph-AMR), defined as controller fills divided by controller plus rescue fills. Higher values are superior because they indicate more controller compared with rescue fills. The outcome was the asthma-related utilization rate among children in the same census tract as the pharmacy, calculated by dividing all emergency visits and hospitalizations by the number of children in that tract. Covariates, including ecological measures of poverty and access to care, were used in multivariable linear regression. RESULTS: Overall, 35 467 medications were filled. The median Ph-AMR was 0.53 (range 0.38–0.66). The median utilization rate across included census tracts was 22.4 visits per 1000 child-years (range 1.3–60.9). Tracts with Ph-AMR <0.5 had significantly higher utilization rates than those with Ph-AMR ≥0.5 (26.1 vs 9.9; P = .001). For every 0.1 increase in Ph-AMR, utilization rates decreased by 9.5 (P = .03), after adjustment for underlying poverty and access. Seasonal variation in fills was evident, but pharmacies in high-utilizing tracts filled more rescue than controller medications at nearly every point during the study period. CONCLUSIONS: Ph-AMR was independently associated with ecological childhood asthma morbidity. Pharmacies may be a community-based leverage point for improving population-level asthma control through targeted interventions. PMID:25941301

  19. Does Marital Status Predict the Odds of Suicidal Death in Taiwan? A Seven-Year Population-Based Study

    ERIC Educational Resources Information Center

    Yeh, Jui-Yuan; Xirasagar, Sudha; Liu, Tsai-Ching; Li, Chong-Yi; Lin, Herng-Ching

    2008-01-01

    Using nationwide, 7-year population-based data for 1997-2003, we examined marital status to see if it predicted suicide among the ethnic Chinese population of Taiwan. Using cause of death data, with a case-control design, two groups--total adult suicide deaths, n = 17,850, the study group, and adult deaths other than suicide, n = 71,400 (randomly…

  20. Population differences in finger-length ratios: ethnicity or latitude?

    PubMed

    Loehlin, John C; McFadden, Dennis; Medland, Sarah E; Martin, Nicholas G

    2006-12-01

    The relative length of the second and fourth fingers (the 2D:4D ratio) has been taken to be an indicator of prenatal exposure to testosterone, and hence possibly relevant to sexual orientation and other sex-differentiated behaviors. Studies have reported a difference in this ratio between Caucasian males in Britain and in the U.S.: higher average 2D:4D ratios were obtained in Britain. This raises the question of whether differences among different Caucasian gene pools were responsible or whether some environmental variable associated with latitude might be involved (e.g., exposure to sunlight or different day-length patterns). This question was explored by examining 2D:4D ratios for an Australian adolescent sample. The Australians were predominantly of British ancestry, but lived at distances from the equator more like those of the U.S. studies. The Australian 2D:4D ratios resembled those in Britain rather than those in the U.S., tending to exclude hypotheses related to latitude and making differences in gene pools a plausible explanation. PMID:16688484

  1. Ecological context and metapopulation dynamics affect sex-ratio variation among dioecious plant populations

    PubMed Central

    Field, David L.; Pickup, Melinda; Barrett, Spencer C. H.

    2013-01-01

    Background and Aims Populations of dioecious flowering plants commonly exhibit heterogeneity in sex ratios and deviations from the equilibrium expectation of equal numbers of females and males. Yet the role of ecological and demographic factors in contributing towards biased sex ratios is currently not well understood. Methods Species-level studies from the literature were analysed to investigate ecological correlates of among-population sex-ratio variation and metapopulation models and empirical data were used to explore the influence of demography and non-equilibrium conditions on flowering sex ratios. Key Results The survey revealed significant among-population heterogeneity in sex ratios and this was related to the degree of sampling effort. For some species, sex-ratio bias was associated with the proportion of non-reproductive individuals, with greater male bias in populations with a lower proportion of individuals that were flowering. Male-biased ratios were also found at higher altitudes and latitudes, and in more xeric sites. Simulations and empirical data indicated that clonal species exhibited greater heterogeneity in sex ratios than non-clonal species as a result of their slower approach to equilibrium. The simulations also indicated the importance of interactions between reproductive mode and founder effects, with greater departures from equilibrium in clonal populations with fewer founding individuals. Conclusions The results indicate that sex-based differences in costs of reproduction and non-equilibrium conditions can each play important roles in affecting flowering sex ratios in populations of dioecious plants. PMID:23444124

  2. Does breeding population trajectory and age of nesting females influence disparate nestling sex ratios in two populations of Cooper's hawks?

    PubMed

    Rosenfield, Robert N; Stout, William E; Giovanni, Matthew D; Levine, Noah H; Cava, Jenna A; Hardin, Madeline G; Haynes, Taylor G

    2015-09-01

    Offspring sex ratios at the termination of parental care should theoretically be skewed toward the less expensive sex, which in most avian species would be females, the smaller gender. Among birds, however, raptors offer an unusual dynamic because they exhibit reversed size dimorphism with females being larger than males. And thus theory would predict a preponderance of male offspring. Results for raptors and birds in general have been varied although population-level estimates of sex ratios in avian offspring are generally at unity. Adaptive adjustment of sex ratios in avian offspring is difficult to predict perhaps in part due to a lack of life-history details and short-term investigations that cannot account for precision or repeatability of sex ratios across time. We conducted a novel comparative study of sex ratios in nestling Cooper's hawks (Accipiter cooperii) in two study populations across breeding generations during 11 years in Wisconsin, 2001-2011. One breeding population recently colonized metropolitan Milwaukee and exhibited rapidly increasing population growth, while the ex-Milwaukee breeding population was stable. Following life-history trade-off theory and our prediction regarding this socially monogamous species in which reversed sexual size dimorphism is extreme, first-time breeding one-year-old, second-year females in both study populations produced a preponderance of the smaller and cheaper sex, males, whereas ASY (after-second-year), ≥2-year-old females in Milwaukee produced a nestling sex ratio near unity and predictably therefore a greater proportion of females compared to ASY females in ex-Milwaukee who produced a preponderance of males. Adjustment of sex ratios in both study populations occurred at conception. Life histories and selective pressures related to breeding population trajectory in two age cohorts of nesting female Cooper's hawk likely vary, and it is possible that these differences influenced the sex ratios we documented for

  3. Odds per adjusted standard deviation: comparing strengths of associations for risk factors measured on different scales and across diseases and populations.

    PubMed

    Hopper, John L

    2015-11-15

    How can the "strengths" of risk factors, in the sense of how well they discriminate cases from controls, be compared when they are measured on different scales such as continuous, binary, and integer? Given that risk estimates take into account other fitted and design-related factors-and that is how risk gradients are interpreted-so should the presentation of risk gradients. Therefore, for each risk factor X0, I propose using appropriate regression techniques to derive from appropriate population data the best fitting relationship between the mean of X0 and all the other covariates fitted in the model or adjusted for by design (X1, X2, … , Xn). The odds per adjusted standard deviation (OPERA) presents the risk association for X0 in terms of the change in risk per s = standard deviation of X0 adjusted for X1, X2, … , Xn, rather than the unadjusted standard deviation of X0 itself. If the increased risk is relative risk (RR)-fold over A adjusted standard deviations, then OPERA = exp[ln(RR)/A] = RR(s). This unifying approach is illustrated by considering breast cancer and published risk estimates. OPERA estimates are by definition independent and can be used to compare the predictive strengths of risk factors across diseases and populations. PMID:26520360

  4. Aberrations Involving Chromosome 1 as a Possible Predictor of Odds Ratio for Colon Cancer - Results from the Krakow Case-Control Study

    PubMed Central

    Galas, Aleksander; Miszczyk, Justyna

    2016-01-01

    Background There is still an open question how to predict colorectal cancer risk before any morphological changes appear in the colon. Objective The purpose was to investigate aberrations in chromosomes 1, 2 and 4 in peripheral blood lymphocytes analyzed by fluorescence in situ hybridization technique as a tool to assess the likelihood of colorectal cancer. Methods A hospital-based case-control study included 20 colon cancer patients and 18 hospital-based controls. Information about potential covariates was collected by interview. The frequency of stable and unstable chromosome aberrations in chromosome 1, 2 and 4 was assessed by fluorescence in situ hybridization technique. Results Colorectal cancer patients, as compared to controls, had a relatively higher frequency of chromosome 1 translocations (median: 3.5 versus 1.0 /1000 cells, p = 0.006), stable aberrations (3.8 versus 1.0 /1000 cells, p = 0.007) and total aberrations (p = 0.009). There were no differences observed for chromosomes 2 and 4. Our results showed an increase in the odds of having colon cancer by about 50–80% associated with an increase by 1/1000 cells in the number of chromosome 1 aberrations. Conclusions The results revealed that the frequency of chromosomal aberrations, especially translocations in chromosome 1, seems to be a promising method to show a colon cancer risk. Additionally, our study suggests the reasonableness of use of biomarkers such as chromosome 1 aberrations in peripheral blood lymphocytes in screening prevention programs for individuals at higher colon cancer risk to identify those who are at increased risk and require more frequent investigations, e.g. by sigmoidoscopy. PMID:26824604

  5. Bayesian Reconstruction of Two-Sex Populations by Age: Estimating Sex Ratios at Birth and Sex Ratios of Mortality1

    PubMed Central

    Wheldon, Mark C.; Raftery, Adrian E.; Clark, Samuel J.; Gerland, Patrick

    2014-01-01

    Summary The original version of Bayesian reconstruction, a method for estimating age-specific fertility, mortality, migration and population counts of the recent past with uncertainty, produced estimates for female-only populations. Here we show how two-sex populations can be similarly reconstructed and probabilistic estimates of various sex ratio quantities obtained. We demonstrate the method by reconstructing the populations of India from 1971 to 2001, Thailand from 1960 to 2000, and Laos from 1985 to 2005. We found evidence that in India, sex ratio at birth exceeded its conventional upper limit of 1.06, and, further, increased over the period of study, with posterior probability above 0.9. In addition, almost uniquely, we found evidence that life expectancy at birth (e0) was lower for females than for males in India (posterior probability for 1971–1976 equal to 0.79), although there was strong evidence for a narrowing of the gap through to 2001. In both Thailand and Laos, we found strong evidence for the more usual result that e0 was greater for females and, in Thailand, that the difference increased over the period of study. PMID:26612972

  6. Age and Sex Ratios in a High-Density Wild Red-Legged Partridge Population

    PubMed Central

    Nadal, Jesús; Ponz, Carolina; Margalida, Antoni

    2016-01-01

    The dynamics of a wild red-legged partridge population were examined over a 14-year period in Spain to identify patterns in age and sex ratios in relation to weather parameters, and to assess the importance of these parameters in population dynamics and management. The results gave age ratios of 1.07 (but 2.13 in July counts), juvenile sex ratios of 1.01 and adult sex ratios of 1.47. Overall, 12% more females were hatched and female juvenile mortality was 7.3% higher than in males. Sex differential mortality explains the 19.2% deficit in adult females, which are more heavily predated than males during the breeding period. Accordingly, age ratios are dependent on sex ratios and both are density dependent. Over time, ratios and density changes appear to be influenced by weather and management. When the habitat is well conserved, partridge population dynamics can be explained by a causal chain: weather operates on net primary production, thereby affecting partridge reproduction and predation and, as a result, age and sex ratios in the October population. A reduction in the impact of predation (i.e. the effects of ground predators on eggs, chicks and breeding females) is the key factor to improve the conservation of partridge populations and associated biological processes. PMID:27508503

  7. Age and Sex Ratios in a High-Density Wild Red-Legged Partridge Population.

    PubMed

    Nadal, Jesús; Ponz, Carolina; Margalida, Antoni

    2016-01-01

    The dynamics of a wild red-legged partridge population were examined over a 14-year period in Spain to identify patterns in age and sex ratios in relation to weather parameters, and to assess the importance of these parameters in population dynamics and management. The results gave age ratios of 1.07 (but 2.13 in July counts), juvenile sex ratios of 1.01 and adult sex ratios of 1.47. Overall, 12% more females were hatched and female juvenile mortality was 7.3% higher than in males. Sex differential mortality explains the 19.2% deficit in adult females, which are more heavily predated than males during the breeding period. Accordingly, age ratios are dependent on sex ratios and both are density dependent. Over time, ratios and density changes appear to be influenced by weather and management. When the habitat is well conserved, partridge population dynamics can be explained by a causal chain: weather operates on net primary production, thereby affecting partridge reproduction and predation and, as a result, age and sex ratios in the October population. A reduction in the impact of predation (i.e. the effects of ground predators on eggs, chicks and breeding females) is the key factor to improve the conservation of partridge populations and associated biological processes. PMID:27508503

  8. Under what conditions do climate-driven sex ratios enhance versus diminish population persistence?

    PubMed Central

    Boyle, Maria; Hone, Jim; Schwanz, Lisa E; Georges, Arthur

    2014-01-01

    For many species of reptile, crucial demographic parameters such as embryonic survival and individual sex (male or female) depend on ambient temperature during incubation. While much has been made of the role of climate on offspring sex ratios in species with temperature-dependent sex determination (TSD), the impact of variable sex ratio on populations is likely to depend on how limiting male numbers are to female fecundity in female-biased populations, and whether a climatic effect on embryonic survival overwhelms or interacts with sex ratio. To examine the sensitivity of populations to these interacting factors, we developed a generalized model to explore the effects of embryonic survival, hatchling sex ratio, and the interaction between these, on population size and persistence while varying the levels of male limitation. Populations with TSD reached a greater maximum number of females compared to populations with GSD, although this was often associated with a narrower range of persistence. When survival depended on temperature, TSD populations persisted over a greater range of temperatures than GSD populations. This benefit of TSD was greatly reduced by even modest male limitation, indicating very strong importance of this largely unmeasured biologic factor. Finally, when males were not limiting, a steep relationship between sex ratio and temperature favoured population persistence across a wider range of climates compared to the shallower relationships. The opposite was true when males were limiting – shallow relationships between sex ratio and temperature allowed greater persistence. The results highlight that, if we are to predict the response of populations with TSD to climate change, it is imperative to 1) accurately quantify the extent to which male abundance limits female fecundity, and 2) measure how sex ratios and peak survival coincide over climate. PMID:25512848

  9. Estimation of wildlife population ratios incorporating survey design and visibility bias

    USGS Publications Warehouse

    Samuel, M.D.; Steinhorst, R.K.; Garton, E.O.; Unsworth, J.W.

    1992-01-01

    Age and sex ratio statistics are often a key component of the evaluation and management of wildlife populations. These statistics are determined from counts of animals that are commonly plagued by errors associated with either survey design or visibility bias. We present age and sex ratio estimators that incorporate both these sources of error and include the typical situation that animals are sampled in groups. Aerial surveys of elk (Cervus elaphus) in northcentral Idaho illustrate that differential visibility of age or sex classes can produce biased ratio estimates. Visibility models may be used to provide corrected estimates of ratios and their variability that incorporates errors due to sampling, visibility bias, and visibility estimation.

  10. Bolton tooth size ratio among Sudanese Population sample: A preliminary study

    PubMed Central

    Abdalla Hashim, Ala’a Hayder; Eldin, AL-Hadi Mohi; Hashim, Hayder Abdalla

    2015-01-01

    Background: The study of the mesiodistal size, the morphology of teeth and dental arch may play an important role in clinical dentistry, as well as other sciences such as Forensic Dentistry and Anthropology. Aims: The aims of the present study were to establish tooth-size ratio in Sudanese sample with Class I normal occlusion, to compare the tooth-size ratio between the present study and Bolton's study and between genders. Materials and Methods: The sample consisted of dental casts of 60 subjects (30 males and 30 females). Bolton formula was used to compute the overall and anterior ratio. The correlation coefficient between the anterior ratio and overall ratio was tested, and Student's t-test was used to compare tooth-size ratios between males and females, and between the present study and Bolton's result. Results: The results of the overall and anterior ratio was relatively similar to the mean values reported by Bolton, and there were no statistically significant differences between the mean values of the anterior ratio and the overall ratio between males and females. The correlation coefficient was (r = 0.79). Conclusions: The result obtained was similar to the Caucasian race. However, the reality indicates that the Sudanese population consisted of different racial groups; therefore, the firm conclusion is difficult to draw. Since this sample is not representative for the Sudanese population, hence, a further study with a large sample collected from the different parts of the Sudan is required. PMID:26229948

  11. Adaptive sex ratio variation in pre-industrial human (Homo sapiens) populations?

    PubMed Central

    Lummaa, V; Merilä, J; Kause, A

    1998-01-01

    Sex allocation theory predicts that in a population with a biased operational sex ratio (OSR), parents will increase their fitness by adjusting the sex ratio of their progeny towards the rarer sex, until OSR has reached a level where the overproduction of either sex no longer increases a parent's probability of having grandchildren. Furthermore, in a monogamous mating system, a biased OSR is expected to lead to lowered mean fecundity among individuals of the more abundant sex. We studied the influence of OSR on the sex ratio of newborns and on the population birth rate using an extensive data set (n = 14,420 births) from pre-industrial (1775-1850) Finland. The overall effect of current OSR on sex ratio at birth was significant, and in the majority of the 21 parishes included in this study, more sons were produced when males were rarer than females. This suggests that humans adjusted the sex ratio of their offspring in response to the local OSR to maximize the reproductive success of their progeny. Birth rate and, presumably, also population growth rate increased when the sex ratio (males:females) among reproductive age classes approached equality. However, the strength of these patterns varied across the parishes, suggesting that factors other than OSR (e.g. socioeconomic or environmental factors may also have influenced the sex ratio at birth and the birth rate. PMID:9881467

  12. Persistent unequal sex ratio in a population of grayling (Salmonidae) and possible role of temperature increase.

    PubMed

    Wedekind, Claus; Evanno, Guillaume; Székely, Tamás; Pompini, Manuel; Darbellay, Olivier; Guthruf, Joachim

    2013-02-01

    In some fishes, water chemistry or temperature affects sex determination or creates sex-specific selection pressures. The resulting population sex ratios are hard to predict from laboratory studies if the environmental triggers interact with other factors, whereas in field studies, singular observations of unusual sex ratios may be particularly prone to selective reporting. Long-term monitoring largely avoids these problems. We studied a population of grayling (Thymallus thymallus) in Lake Thun, Switzerland, that has been monitored since 1948. Samples of spawning fish have been caught about 3 times/week around spawning season, and water temperature at the spawning site has been continuously recorded since 1970. We used scale samples collected in different years to determine the average age of spawners (for life-stage specific analyses) and to identify the cohort born in 2003 (an extraordinarily warm year). Recent tissue samples were genotyped on microsatellite markers to test for genetic bottlenecks in the past and to estimate the genetically effective population size (N(e)). Operational sex ratios changed from approximately 65% males before 1993 to approximately 85% males from 1993 to 2011. Sex ratios correlated with the water temperatures the fish experienced in their first year of life. Sex ratios were best explained by the average temperature juvenile fish experienced during their first summer. Grayling abundance is declining, but we found no evidence of a strong genetic bottleneck that would explain the apparent lack of evolutionary response to the unequal sex ratio. Results of other studies show no evidence of endocrine disruptors in the study area. Our findings suggest temperature affects population sex ratio and thereby contributes to population decline. PMID:22891785

  13. Does polyandry control population sex ratio via regulation of a selfish gene?

    PubMed Central

    Price, Tom A. R.; Bretman, Amanda; Gradilla, Ana C.; Reger, Julia; Taylor, Michelle L.; Giraldo-Perez, Paulina; Campbell, Amy; Hurst, Gregory D. D.; Wedell, Nina

    2014-01-01

    The extent of female multiple mating (polyandry) can strongly impact on the intensity of sexual selection, sexual conflict, and the evolution of cooperation and sociality. More subtly, polyandry may protect populations against intragenomic conflicts that result from the invasion of deleterious selfish genetic elements (SGEs). SGEs commonly impair sperm production, and so are likely to be unsuccessful in sperm competition, potentially reducing their transmission in polyandrous populations. Here, we test this prediction in nature. We demonstrate a heritable latitudinal cline in the degree of polyandry in the fruitfly Drosophila pseudoobscura across the USA, with northern population females remating more frequently in both the field and the laboratory. High remating was associated with low frequency of a sex-ratio-distorting meiotic driver in natural populations. In the laboratory, polyandry directly controls the frequency of the driver by undermining its transmission. Hence we suggest that the cline in polyandry represents an important contributor to the cline in sex ratio in nature. Furthermore, as the meiotic driver causes sex ratio bias, variation in polyandry may ultimately determine population sex ratio across the USA, a dramatic impact of female mating decisions. As SGEs are ubiquitous it is likely that the reduction of intragenomic conflict by polyandry is widespread. PMID:24695427

  14. Population sex-ratio affecting behavior and physiology of overwintering bank voles (Myodes glareolus).

    PubMed

    Sipari, Saana; Haapakoski, Marko; Klemme, Ines; Palme, Rupert; Sundell, Janne; Ylönen, Hannu

    2016-05-15

    Many boreal rodents are territorial during the breeding season but during winter become social and aggregate for more energy efficient thermoregulation. Communal winter nesting and social interactions are considered to play an important role for the winter survival of these species, yet the topic is relatively little explored. Females are suggested to be the initiators of winter aggregations and sometimes reported to survive better than males. This could be due to the higher social tolerance observed in overwintering females than males. Hormonal status could also affect winter behavior and survival. For instance, chronic stress can have a negative effect on survival, whereas high gonadal hormone levels, such as testosterone, often induce aggressive behavior. To test if the winter survival of females in a boreal rodent is better than that of males, and to assess the role of females in the winter aggregations, we generated bank vole (Myodes glareolus) populations of three different sex ratios (male-biased, female-biased and even density) under semi-natural conditions. We monitored survival, spatial behavior and hormonal status (stress and testosterone) during two winter months. We observed no significant differences in survival between the sexes or among populations with differing sex-ratios. The degree of movement area overlap was used as an indicator of social tolerance and potential communal nesting. Individuals in male biased populations showed a tendency to be solitary, whereas in female biased populations there was an indication of winter aggregation. Females living in male-biased populations had higher stress levels than the females from the other populations. The female-biased sex-ratio induced winter breeding and elevated testosterone levels in males. Thus, our results suggest that the sex-ratio of the overwintering population can lead to divergent overwintering strategies in bank voles. PMID:26976741

  15. Ratio

    NASA Astrophysics Data System (ADS)

    Webster, Nathan A. S.; Pownceby, Mark I.; Madsen, Ian C.; Studer, Andrew J.; Manuel, James R.; Kimpton, Justin A.

    2014-12-01

    Effects of basicity, B (CaO:SiO2 ratio) on the thermal range, concentration, and formation mechanisms of silico-ferrite of calcium and aluminum (SFCA) and SFCA-I iron ore sinter bonding phases have been investigated using an in situ synchrotron X-ray diffraction-based methodology with subsequent Rietveld refinement-based quantitative phase analysis. SFCA and SFCA-I phases are the key bonding materials in iron ore sinter, and improved understanding of the effects of processing parameters such as basicity on their formation and decomposition may assist in improving efficiency of industrial iron ore sintering operations. Increasing basicity significantly increased the thermal range of SFCA-I, from 1363 K to 1533 K (1090 °C to 1260 °C) for a mixture with B = 2.48, to ~1339 K to 1535 K (1066 °C to 1262 °C) for a mixture with B = 3.96, and to ~1323 K to 1593 K (1050 °C to 1320 °C) at B = 4.94. Increasing basicity also increased the amount of SFCA-I formed, from 18 wt pct for the mixture with B = 2.48 to 25 wt pct for the B = 4.94 mixture. Higher basicity of the starting sinter mixture will, therefore, increase the amount of SFCA-I, considered to be more desirable of the two phases. Basicity did not appear to significantly influence the formation mechanism of SFCA-I. It did, however, affect the formation mechanism of SFCA, with the decomposition of SFCA-I coinciding with the formation of a significant amount of additional SFCA in the B = 2.48 and 3.96 mixtures but only a minor amount in the highest basicity mixture. In situ neutron diffraction enabled characterization of the behavior of magnetite after melting of SFCA produced a magnetite plus melt phase assemblage.

  16. Estimating Consumption to Biomass Ratio in Non-Stationary Harvested Fish Populations.

    PubMed

    Wiff, Rodrigo; Roa-Ureta, Ruben H; Borchers, David L; Milessi, Andrés C; Barrientos, Mauricio A

    2015-01-01

    The food consumption to biomass ratio (C) is one of the most important population parameters in ecosystem modelling because its quantifies the interactions between predator and prey. Existing models for estimating C in fish populations are per-recruit cohort models or empirical models, valid only for stationary populations. Moreover, empirical models lack theoretical support. Here we develop a theory and derive a general modelling framework to estimate C in fish populations, based on length frequency data and the generalised von Bertalanffy growth function, in which models for stationary populations with a stable-age distributions are special cases. Estimates using our method are compared with estimates from per-recruit cohort models for C using simulated harvested fish populations of different lifespans. The models proposed here are also applied to three fish populations that are targets of commercial fisheries in southern Chile. Uncertainty in the estimation of C was evaluated using a resampling approach. Simulations showed that stationary and non-stationary population models produce different estimates for C and those differences depend on the lifespan, fishing mortality and recruitment variations. Estimates of C using the new model exhibited smoother inter-annual variation in comparison with a per-recruit model estimates and they were also smaller than C predicted by the empirical equations in all population assessed. PMID:26528721

  17. Estimating Consumption to Biomass Ratio in Non-Stationary Harvested Fish Populations

    PubMed Central

    Wiff, Rodrigo; Roa-Ureta, Ruben H.; Borchers, David L.; Milessi, Andrés C.; Barrientos, Mauricio A.

    2015-01-01

    The food consumption to biomass ratio (C) is one of the most important population parameters in ecosystem modelling because its quantifies the interactions between predator and prey. Existing models for estimating C in fish populations are per-recruit cohort models or empirical models, valid only for stationary populations. Moreover, empirical models lack theoretical support. Here we develop a theory and derive a general modelling framework to estimate C in fish populations, based on length frequency data and the generalised von Bertalanffy growth function, in which models for stationary populations with a stable-age distributions are special cases. Estimates using our method are compared with estimates from per-recruit cohort models for C using simulated harvested fish populations of different lifespans. The models proposed here are also applied to three fish populations that are targets of commercial fisheries in southern Chile. Uncertainty in the estimation of C was evaluated using a resampling approach. Simulations showed that stationary and non-stationary population models produce different estimates for C and those differences depend on the lifespan, fishing mortality and recruitment variations. Estimates of C using the new model exhibited smoother inter-annual variation in comparison with a per-recruit model estimates and they were also smaller than C predicted by the empirical equations in all population assessed. PMID:26528721

  18. [Offspring Sex Ratio in the Captive Population of Siberian Crane (Grus leucogeranus Pallas)].

    PubMed

    Mudrik, E A; Kashentseva, T A; Postelnykh, K A; Nosachenko, G V; Politov, D V

    2015-12-01

    The sex ratio of Siberian crane chicks (Grus leucogeranus Pallas) from the captive population ofthe Oka Crane Breeding Center was analyzed with the use of molecular sex marker EE0.6 in 2009-2014. We determined the sex of 84 birds bred from 12 dams by means of artificial insemination and natural breeding. The total primary sex ratio was 40:44, and the secondary sex ratio was 36:39 with a minor predominance of females. The mortality rate of embryos was the same for both sexes. The primary and secondary sex ratio among the first eggs in clutches showed the same trends as those observed in general analysis. The relatedness of parents by microsatellite DNA has no effect on offspring sex in both natural breeding and artificial insemination. PMID:27055304

  19. Root-Crown Ratio in Permanent Dentition Using Panoramic Radiography in a Selected Iranian Population

    PubMed Central

    Haghanifar, Sina; Moudi, Ehsan; Abbasi, Shirin; Bijani, Ali; Poorsattar Bejeh Mir, Arash; Ghasemi, Nafiseh

    2014-01-01

    Statement of the Problem: Determining the crown-root ratio is crucial in many dental clinical decisions. There are no reliable data presented for Iranian population. Purpose: The aim of this study was to assess the root-crown ratio of permanent teeth with regards to the relationship of gender and jaw type using panoramic radiographs. The reliability of method was also assessed. Materials and Method: The crown and root lengths of teeth were measured by a digital caliper on panoramic radiographs of 185 individuals except for the third molars. A total of 1994 teeth was studied and 50.8% of the teeth belonged to males and 49.2% belonged to females. The modified Lind method was applied. Results: The highest mean root-crown ratios in both arches of both genders were obtained in the second premolars, followed by the first premolars and canines. In both genders, the lowest root-crown ratios were found in the maxillary central incisors. In male patients, the mean root-crown ratio was higher (p= 0.003) than that of females. Using Bland-Altman analysis, a non-significant difference of 0.006 (95% CI: -0.012-0.024) and 0.0002 (95% CI: -0.011-0.011) were found for intra-observer and inter-observer agreement, respectively. Conclusion: Assessment of the root-crown ratio in permanent dentition could be performed on panoramic radiographs with acceptable reproducibility in an Iranian Population. Considering observed differences, our findings suggest that for the accurate assessment, this ratio must be calculated for male and female patients and also for the upper and lower jaws, separately. PMID:25469356

  20. Dietary magnesium, calcium:magnesium ratio and risk of reflux oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma: a population-based case-control study.

    PubMed

    Dai, Qi; Cantwell, Marie M; Murray, Liam J; Zheng, Wei; Anderson, Lesley A; Coleman, Helen G

    2016-01-28

    Evidence suggests a role of Mg and the ratio of Ca:Mg intakes in the prevention of colonic carcinogenesis. The association between these nutrients and oesophageal adenocarcinoma - a tumour with increasing incidence in developed countries and poor survival rates - has yet to be explored. The aim of this investigation was to explore the association between Mg intake and related nutrients and risk of oesophageal adenocarcinoma and its precursor conditions, Barrett's oesophagus and reflux oesophagitis. This analysis included cases of oesophageal adenocarcinoma (n 218), Barrett's oesophagus (n 212), reflux oesophagitis (n 208) and population-based controls (n 252) recruited between 2002 and 2005 throughout the island of Ireland. All the subjects completed a 101-item FFQ. Unconditional logistic regression analysis was applied to determine odds of disease according to dietary intakes of Mg, Ca and Ca:Mg ratio. After adjustment for potential confounders, individuals consuming the highest amounts of Mg from foods had significant reductions in the odds of reflux oesophagitis (OR 0·31; 95 % CI 0·11, 0·87) and Barrett's oesophagus (OR 0·29; 95 % CI 0·12, 0·71) compared with individuals consuming the lowest amounts of Mg. The protective effect of Mg was more apparent in the context of a low Ca:Mg intake ratio. No significant associations were observed for Mg intake and oesophageal adenocarcinoma risk (OR 0·77; 95 % CI 0·30, 1·99 comparing the highest and the lowest tertiles of consumption). In conclusion, dietary Mg intakes were inversely associated with reflux oesophagitis and Barrett's oesophagus risk in this Irish population. PMID:26563986

  1. Inbreeding and Offspring Sex Ratio in the Pygmy Hippopotamus (Cheoropsis liberiensis) Population Kept in Zoological Gardens.

    PubMed

    Graczyk, Magdalena; Cwiertnia, Piotr; Borowska, Alicja; Barczak, Elżbieta; Szwaczkowski, Tomasz

    2015-01-01

    The aim of this study was to estimate the inbreeding level and its impact on offspring sex ratio in the pygmy hippopotamus population kept in zoological gardens. Records of pygmy hippopotamus born between 1873-2013 were extracted from the international studbook. Totally, 1357 individuals originating from 148 breeding units were included (individuals with unknown sex were omitted). The offspring sex ratio is defined as the number of sons to the total number of progeny of each dam and sire. Spearman's rank correlation was employed to examine the relationships between the inbreeding level and offspring sex ratio. Inbreeding coefficients and individual increase in inbreeding coefficients (included as a linear co-variable) were examined as well as the geographic region and birth period using general linear models. The average inbreeding coefficient was 5.39%. The following sex proportion was observed for the inbred population: 57% and 43% for females and males, respectively. A significant relationship between inbreeding level of parents and their offspring sex ratio were estimated for European zoological gardens, whereas in others geographic regions the dependencies were insignificant. PMID:26103683

  2. Level structures in odd-odd deformed nucleus 184Ta

    NASA Astrophysics Data System (ADS)

    Gowrishankar, R.; Sood, P. C.

    2016-02-01

    A detailed low-energy level scheme of the odd-odd n-rich nucleus 184 73Ta111 is constructed using the well tested Two-Quasiparticle Rotor Model (TQRM) for calculating the bandhead energies of physically admissible 2qp configurations with the inclusion of residual n-p interaction contribution. The presently available data on this level scheme from 184Hf decay are shown to be in agreement with these calculations. Our analysis concludes that 184Hf ( Q_{β}=1340(30) keV) decay admits of 7 additional (to the 3 presently reported) β-branches to 184Ta with J = 0 or 1 and 8 more physically admissible weak ( 1fu β-branches populating J^{π}=2- levels in 184Ta. Further, a close examination of our level scheme clearly indicates the existence of a low-lying ( Ex = 260(40) keV) high-spin ( J^{π}=10-) long-lived isomer in this nucleus.

  3. Between-year variation in population sex ratio increases with complexity of the breeding system in Hymenoptera.

    PubMed

    Kümmerli, Rolf; Keller, Laurent

    2011-06-01

    While adaptive adjustment of sex ratio in the function of colony kin structure and food availability commonly occurs in social Hymenoptera, long-term studies have revealed substantial unexplained between-year variation in sex ratio at the population level. In order to identify factors that contribute to increased between-year variation in population sex ratio, we conducted a comparative analysis across 47 Hymenoptera species differing in their breeding system. We found that between-year variation in population sex ratio steadily increased as one moved from solitary species, to primitively eusocial species, to single-queen eusocial species, to multiple-queen eusocial species. Specifically, between-year variation in population sex ratio was low (6.6% of total possible variation) in solitary species, which is consistent with the view that in solitary species, sex ratio can vary only in response to fluctuations in ecological factors such as food availability. In contrast, we found significantly higher (19.5%) between-year variation in population sex ratio in multiple-queen eusocial species, which supports the view that in these species, sex ratio can also fluctuate in response to temporal changes in social factors such as queen number and queen-worker control over sex ratio, as well as factors influencing caste determination. The simultaneous adjustment of sex ratio in response to temporal fluctuations in ecological and social factors seems to preclude the existence of a single sex ratio optimum. The absence of such an optimum may reflect an additional cost associated with the evolution of complex breeding systems in Hymenoptera societies. PMID:21597259

  4. Effects of pressure ratio on population inversion in a DF chemical laser with concurrent lasing

    NASA Astrophysics Data System (ADS)

    Park, Jun Sung; Baek, Seung Wook

    2005-04-01

    A numerical simulation is presented for investigating the effects of pressure ratio of D2 injector to supersonic nozzle on the population inversion in the DF chemical laser cavity, while a lasing concurrently takes place. The chemical laser is generally used for the industrial process and manufacturing as well as the military weapon system, which requires high power characteristic of laser system rather than the others. The population inversion is absolutely needed to generate the laser beam and is non-equilibrium process. The laser beam is generated between the mirrors in the cavity and it is important to obtain stronger population inversion and more uniform distribution of the excited molecules in the laser cavity in order to produce high-power laser beam with good quality. In this study, these phenomena are investigated by means of analyzing the distributions of the DF excited molecules and the F atom used as an oxidant, while simultaneously estimating the maximum small signal and saturated gains and power in the DF chemical laser cavity. For the numerical solution, a fully conservative implicit method and a second order total variation diminishing (TVD) scheme are used with the finite-volume method (FVM). An 11-species (including DF molecules in various excited states of energies), 32-step chemistry model is adopted for the chemical reaction of the DF chemical laser system. The results are discussed by comparison with two D2 injector pressure cases; 192 and 388.64 torr. Major results reveal that in the resonator, stronger population inversions occur in the all transitions except DF(1)-DF(0), when the D2 injection pressure is lower. But, the higher D2 injection pressure provides a favorable condition for DF(1)-DF(0) transition to generate the higher power laser beam. In other words, as the pressure of D2 injector increases, the maximum small signal gain in the v transition, which is in charge of generating most of laser power, becomes higher. Therefore, the

  5. Sex ratio of congenital abnormalities in the function of maternal age: a population-based study.

    PubMed

    Csermely, Gyula; Urbán, Robert; Czeizel, Andrew E; Veszprémi, Béla

    2015-05-01

    Maternal age effect is well-known in the origin of numerical chromosomal aberrations and some isolated congenital abnormalities (CAs). The sex ratio (SR), i.e. number of males divided by the number of males and females together, of most CAs deviates from the SR of newborn population (0.51). The objective of this analysis was to evaluate the possible association of maternal age with the SR of isolated CAs in a population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. First, SR of 24 CA entities/groups was estimated in 21,494 patients with isolated CA. In the next step SR of different maternal age groups was compared to the mean SR of the given CA-groups. The SR of four CA-groups showed some deviation in certain maternal age groups. Cases with anencephaly had female excess in young mothers (<25 years). Cases with skull's CAs particularly craniosynostosis had a male excess in cases born to women over 30 years. Two other CA groups (cleft lip ± palate and valvar pulmonic stenosis within the group of right-sided obstructive defect of heart) had significant deviation in SR of certain maternal age groups from the mean SR, but these deviations were not harmonized with joining age groups and thus were considered as a chance effect due to multiple testing. In conclusion, our study did not suggest that in general SR of isolated CAs might be modified by certain maternal age groups with some exception such as anencephaly and craniosynostosis. PMID:25354028

  6. Genetic diversity and genetic structure of different types of natural populations in Osmanthus fragrans Lour. and the relationships with sex ratio, population structure, and geographic isolation.

    PubMed

    Hu, Shaoqing; Wu, Shuai; Wang, Yiguang; Zhao, Hongbo; Zhang, Yuanyan

    2014-01-01

    Osmanthus fragrans Lour., an evergreen small tree, has the rare sexual system of androdioecy (coexistence of males and hermaphrodites), once with wide-spread natural distribution in the areas of the South Yangzi river basin. However, due to excessive human utilization, natural distribution became fragmented and the number and size of natural populations reduced sharply. With four different types of natural populations from the same region as research object, we aim to provide a comparative analysis on the relationships among genetic diversity, sexual system, population structure and size, and geographic isolation by ISSR. In genetic parameters of N e , H e , and I, the LQGC population had the highest value and the LQZGQ population had the lowest value. These indicated that LQGC population showed the highest genetic diversity, followed by QDH and JN population, and LQZGQ population exhibited the lowest genetic diversity. Genetic diversity in populations is closely related to population structure, reproduction mode, and sex ratio. However, there seems to be no obvious correlation between genetic diversity and population size. The results of AMOVA showed that genetic variations mostly occurred within populations. It indicates that no significant genetic differentiation among populations occurs, and geographic isolation has no significant effect on genetic diversity. PMID:25436228

  7. Genetic Diversity and Genetic Structure of Different Types of Natural Populations in Osmanthus fragrans Lour. and the Relationships with Sex Ratio, Population Structure, and Geographic Isolation

    PubMed Central

    Hu, Shaoqing; Wu, Shuai; Wang, Yiguang; Zhang, Yuanyan

    2014-01-01

    Osmanthus fragrans Lour., an evergreen small tree, has the rare sexual system of androdioecy (coexistence of males and hermaphrodites), once with wide-spread natural distribution in the areas of the South Yangzi river basin. However, due to excessive human utilization, natural distribution became fragmented and the number and size of natural populations reduced sharply. With four different types of natural populations from the same region as research object, we aim to provide a comparative analysis on the relationships among genetic diversity, sexual system, population structure and size, and geographic isolation by ISSR. In genetic parameters of Ne, He, and I, the LQGC population had the highest value and the LQZGQ population had the lowest value. These indicated that LQGC population showed the highest genetic diversity, followed by QDH and JN population, and LQZGQ population exhibited the lowest genetic diversity. Genetic diversity in populations is closely related to population structure, reproduction mode, and sex ratio. However, there seems to be no obvious correlation between genetic diversity and population size. The results of AMOVA showed that genetic variations mostly occurred within populations. It indicates that no significant genetic differentiation among populations occurs, and geographic isolation has no significant effect on genetic diversity. PMID:25436228

  8. Against the Odds Exhibition Opens

    MedlinePlus

    ... Bar Home Current Issue Past Issues Special Section Against the Odds Exhibition Opens Past Issues / Spring 2008 ... Research in Bethesda. Photo courtesy of Bill Branson "Against the Odds" is a remarkable story of achievement ...

  9. Simple life-history traits explain key effective population size ratios across diverse taxa

    PubMed Central

    Waples, Robin S.; Luikart, Gordon; Faulkner, James R.; Tallmon, David A.

    2013-01-01

    Effective population size (Ne) controls both the rate of random genetic drift and the effectiveness of selection and migration, but it is difficult to estimate in nature. In particular, for species with overlapping generations, it is easier to estimate the effective number of breeders in one reproductive cycle (Nb) than Ne per generation. We empirically evaluated the relationship between life history and ratios of Ne, Nb and adult census size (N) using a recently developed model (agene) and published vital rates for 63 iteroparous animals and plants. Nb/Ne varied a surprising sixfold across species and, contrary to expectations, Nb was larger than Ne in over half the species. Up to two-thirds of the variance in Nb/Ne and up to half the variance in Ne/N was explained by just two life-history traits (age at maturity and adult lifespan) that have long interested both ecologists and evolutionary biologists. These results provide novel insights into, and demonstrate a close general linkage between, demographic and evolutionary processes across diverse taxa. For the first time, our results also make it possible to interpret rapidly accumulating estimates of Nb in the context of the rich body of evolutionary theory based on Ne per generation. PMID:23926150

  10. Dispersal, niche breadth and population extinction: colonization ratios predict range size in North American dragonflies.

    PubMed

    McCauley, Shannon J; Davis, Christopher J; Werner, Earl E; Robeson, Michael S

    2014-07-01

    negative relationship between North American range size and species' extinction-to-colonization ratios. Our results indicate that metapopulation dynamics act to shape the extent of species' continental distributions. These population dynamics are likely to interact with dispersal behaviour, particularly at species range margins, to determine range limits and ultimately species range sizes. PMID:24237364

  11. Disentangling the effect of genes, the environment and chance on sex ratio variation in a wild bird population.

    PubMed

    Postma, Erik; Heinrich, Franziska; Koller, Ursina; Sardell, Rebecca J; Reid, Jane M; Arcese, Peter; Keller, Lukas F

    2011-10-01

    Sex ratio theory proposes that the equal sex ratio typically observed in birds and mammals is the result of natural selection. However, in species with chromosomal sex determination, the same 1 : 1 sex ratio is expected under random Mendelian segregation. Here, we present an analysis of 14 years of sex ratio data for a population of song sparrows (Melospiza melodia) on Mandarte Island, at the nestling stage and at independence from parental care. We test for the presence of variance in sex ratio over and above the binomial variance expected under Mendelian segregation, and thereby quantify the potential for selection to shape sex ratio. Furthermore, if sex ratio variation is to be shaped by selection, we expect some of this extra-binomial variation to have a genetic basis. Despite ample statistical power, we find no evidence for the existence of either genetic or environmentally induced variation in sex ratio, in the nest or at independence. Instead, the sex ratio variation observed matches that expected under random Mendelian segregation. Using one of the best datasets of its kind, we conclude that female song sparrows do not, and perhaps cannot, adjust the sex of their offspring. We discuss the implications of this finding and make suggestions for future research. PMID:21345862

  12. The lithium isotope ratio in Population II halo dwarfs - A proposed test of the late decaying massive particle nucleosynthesis scenario

    NASA Technical Reports Server (NTRS)

    Brown, Lawrence; Schramm, David N.

    1988-01-01

    It is shown that observations of the lithium isotope ratio in high surface temperature Population II stars may be critical to cosmological nucleosynthesis models. In particular, decaying particle scenarios as derived in some supersymmetric models may stand or fall with such observations.

  13. The Lithium isotope ratio in Population II halo dwarfs: A proposed test of the late decaying massive particle nucleosynthesis scenario

    SciTech Connect

    Brown, L.; Schramm, D.N.

    1988-02-01

    It is shown that observations of the Lithium isotope ratio in high surface temperature Population II stars may be critical to cosmological nucleosynthesis models. In particular, decaying particle scenarios as derived in some supersymmetric models may stand or fall with such observations. 15 refs., 3 figs., 2 tabs.

  14. Population structure and the evolution of sexual size dimorphism and sex ratios in an insular population of Florida box turtles (Terrapene carolina bauri)

    USGS Publications Warehouse

    Dodd, C.K., Jr.

    1997-01-01

    Hypotheses in the chelonian literature suggest that in species with sexual size dimorphism, the smaller sex will mature at a smaller size and a younger age than the larger sex, sex ratios should be biased in favor of the earlier maturing sex, and deviations from a 1:1 sex ratio result from maturation of the smaller sex at a younger age. I tested these hypotheses using data collected from 1991 to 1995 on an insular (Egmont Key) population of Florida box turtles, Terrapene carolina bauri. Contrary to predictions, the earlier maturing sex (males) grew to larger sizes than the late maturing sex. Males were significantly larger than females in mean carapace length but not mean body mass. Sex ratios were not balanced, favoring the earlier maturing sex (1.6 males:1 female), but the sex-ratio imbalance did not result from faster maturation of the smaller sex. The imbalance in the sex ratio in Egmont Key's box turtles is not the result of sampling biases; it may result from nest placement. Size-class structure and sex ratios can provide valuable insights into the status and trends of populations of long-lived turtles.

  15. "Dealing" with Incidence, Prevalence, and Odds Concepts in Undergraduate Epidemiology

    ERIC Educational Resources Information Center

    Senchina, David S.; Laurson, Kelly R.

    2009-01-01

    Concepts and associated statistical formulae of incidence, prevalence, and odds/odds ratios are core knowledge in epidemiology yet can be confusing for students. The purpose of this project was to develop, validate, and share one possible pedagogical technique using playing cards that could be employed to improve undergraduate understanding of…

  16. Tilted axis rotation in odd-odd {sup 164}Tm

    SciTech Connect

    Reviol, W.; Riedinger, L.L.; Wang, X.Z.; Zhang, J.Y.

    1996-12-31

    Ten band structures are observed in {sup 164}Tm, among them sets of parallel and anti-parallel couplings of the proton and neutron spins. The Tilted Axis Cranking scheme is applied for the first time to an odd-odd nucleus in a prominent region of nuclear deformation.

  17. The effects of adult sex ratio on mating competition in male and female guppies (Poecilia reticulata) in two wild populations.

    PubMed

    Chuard, Pierre J C; Brown, Grant E; Grant, James W A

    2016-08-01

    When competing for mates, males typically exhibit higher rates of intrasexual aggression and courtship than females. Operational sex ratio, represented here by adult sex ratio (ASR) as a proxy, is likely the best predictor of this competition, which typically increases between members of one sex as members of the opposite sex become rarer. Moreover, in populations subject to high predation, males often decrease mating competitive behaviour due to predation risk. We explored the combined effects of ASR and population of origin (low vs. high ambient predation risk) on mating competition in male and female wild-caught Trinidadian guppies. Both male and female aggression rates increased with ASR, but the increase for males was only significant in the low-predation population. In regard to male mating tactics, courtship propensity was unaffected by ASR, while the propensity to sneak increased at male-biased ASRs. Guppies from a high predation population had lower aggression rates than their low predation counterpart, but male courtship and sneaking attempts did not differ between populations. Surprisingly, females were just as aggressive as males when competing for mates. These results highlight the trade-offs between antipredator and agonistic behaviour, which may affect sexual selection pressures in wild populations. PMID:27208810

  18. Selected Intakes as Ratios of Energy Intake, U.S. Population, 2001-04

    Cancer.gov

    The NCI Method provides the capability to estimate the distribution of usual food intakes in the US population to greatly enhance the ability to monitor diets relative to recommendations and to assess the scope of dietary deficiencies and excesses.

  19. Genetic Variants Associated with Optic Nerve Vertical Cup-to-Disc Ratio Are Risk Factors for Primary Open Angle Glaucoma in a US Caucasian Population

    PubMed Central

    Fan, Bao Jian; Wang, Dan Yi; Pasquale, Louis R.; Haines, Jonathan L.

    2011-01-01

    Purpose. Genetically complex disorders, such as primary open angle glaucoma (POAG), may include highly heritable quantitative traits as part of the overall phenotype, and mapping genes influencing the related quantitative traits may effectively identify genetic risk factors predisposing to the complex disease. Recent studies have identified SNPs associated with optic nerve area and vertical cup-to-disc ratio (VCDR). The purpose of this study was to evaluate the association between these SNPs and POAG in a US Caucasian case-control sample. Methods. Five SNPs previously associated with optic disc area, or VCDR, were genotyped in 539 POAG cases and 336 controls. Genotype data were analyzed for single SNP associations and SNP interactions with VCDR and POAG. Results. SNPs associated with VCDR rs1063192 (CDKN2B) and rs10483727 (SIX1/SIX6) were also associated with POAG (P = 0.0006 and P = 0.0043 for rs1063192 and rs10483727, respectively). rs1063192, associated with smaller VCDR, had a protective effect (odds ratio [OR] = 0.73; 95% confidence interval [CI], 0.58–0.90), whereas rs10483727, associated with larger VCDR, increased POAG risk (OR = 1.33; 95% CI, 1.08–1.65). POAG risk associated with increased VCDR was significantly influenced by the C allele of rs1900004 (ATOH7), associated with increased optic nerve area (P-interaction = 0.025; OR = 1.89; 95% CI, 1.22–2.94). Conclusions. Genetic variants influencing VCDR are associated with POAG in a US Caucasian population. Variants associated with optic nerve area are not independently associated with disease but can influence the effects of VCDR variants suggesting that increased optic disc area can significantly contribute to POAG risk when coupled with risk factors controlling VCDR. PMID:21398277

  20. Sex-Ratio and Gender Differences in Depression in an Unselected Adult Population.

    ERIC Educational Resources Information Center

    Baumgart, E. P.; Oliver, J. M.

    1981-01-01

    Neither sex-ratio nor gender differences in depression were found in adult sample, similar to pattern found among university students. No demographic variable was correlated significantly with depression. Suggests results may be due to the elimination of face-to-face interviews, which expose males to greater negative repercussions for exhibiting…

  1. Survey of odd-odd deformed nuclear spectroscopy

    SciTech Connect

    Hoff, R.W.

    1993-09-14

    In this paper, we survey the current experimental data that support assignment of rotational bands in odd-odd deformed nuclear in the rare earth and actinide regions. We present the results of a new study of {sup 170}Mt nuclear structure. In a comparing experimental and calculated Gallagher-Moszkowski matrix elements for rare earth-region nuclei, we have developed a new approach to the systematics of these matrix elements.

  2. High nitrate to phosphorus ratio attenuates negative effects of rising pCO2 on net population carbon accumulation

    NASA Astrophysics Data System (ADS)

    Krug, S. A.; Eggers, S. L.; Matthiessen, B.

    2011-07-01

    The ongoing rise in atmospheric pCO2 and the consequent increase in ocean acidification have direct effects on marine calcifying phytoplankton which potentially translates into altered carbon export. To date it remains unclear first, how nutrient ratio, in particular from coccolithophores preferred phosphate limitation, interacts with pCO2 on particulate carbon accumulation. Second, how direct physiological responses on the cellular level translate into a net population response. In this study cultures of Emiliania huxleyi were full-factorially exposed to two different N:P ratios (Redfield and high N:P) and three different pCO2 levels. Effects on net population particulate inorganic and organic carbon (PIC, POC) were measured after E. huxleyi cultures reached stationary phase. Thereby cell sizes and total cell abundance were taken into account. Corresponding to literature results show a significant negative cellular PIC and POC response which, however, was strongest under high N:P ratio. In contrast, net population PIC and POC accumulation was significantly attenuated under high N:P ratio. We suggest that less cellular nutrient accumulation allowed for higher cell abundances which compensated for the strong negative cellular PIC and POC response to pCO2 on the population level. Moreover, the design of this study also allowed following natural alteration of carbon chemistry through changing DIC and alkalinity. Our results suggest that at high initial pCO2 natural alteration of pCO2 during the experimental runtime was regulated by algal biomass. In contrast, at low initial pCO2 the PIC/POC ratio was responsible for changes in pCO2. Our results point to the fact that the physiological (i.e. cellular) PIC and POC response to ocean acidification cannot be linearly extrapolated to total population response and thus carbon export. It is therefore recommended to consider effects of nutrient limitation on cell physiology and translate these to net population carbon

  3. Seasonal variation of morph ratio in facultatively paedomorphic populations of the palmate newt Triturus helveticus

    NASA Astrophysics Data System (ADS)

    Denoël, Mathieu

    2006-03-01

    Facultative paedomorphosis is a polyphenism in which individuals may express one of two alternative ontogenetic pathways (metamorphosis vs. paedomorphosis) depending on environmental cues. Previous laboratory experiments showed that drying can cause morph ratio change, suggesting that the maintenance of facultative paedomorphosis is highly dependent on environmental determinants. The aim of this study was to examine seasonal variation in morph ratios in eight ponds from Larzac (southern France) naturally inhabited by palmate newts and to relate it to pond drying. In some ponds, the relative proportion of paedomorphs (i.e. individuals retaining gills at the adult stage) increased after the breeding period, but it remained stable or decreased in other ponds. This seasonal variation in the abundance of the two morphs most probably reflects (1) the emigration of metamorphs leaving the pond to occupy terrestrial habitats and (2) metamorphosis of paedomorphic adults in response to drying of the ponds. This study shows that facultative paedomorphosis in palmate newts is a dynamic process that allows rapid change (i.e. within a single year) in morph ratio to fit environmental variation (i.e. risk of drying) within the aquatic habitats. Long-term studies are needed to model the evolution of the dimorphism according to environmental change.

  4. Associations between Physical Activity and Obesity Defined by Waist-To-Height Ratio and Body Mass Index in the Korean Population

    PubMed Central

    Lee, On; Lee, Duck-chul; Lee, Sukho; Kim, Yeon Soo

    2016-01-01

    Objective This study investigated the associations between physical activity and the prevalence of obesity determined by waist-to-height ratio (WHtR) and body mass index (BMI). Methods This is the first study to our knowledge on physical activity and obesity using a nationally representative sample of South Korean population from The Korea National Health and Nutrition Examination Survey. We categorized individuals into either non-obese or obese defined by WHtR and BMI. Levels of moderate-to-vigorous physical activity were classified as ‘Inactive’, ‘Active’, and ‘Very active’ groups based on the World Health Organization physical activity guidelines. Multivariable logistic regression was used to examine the associations between physical activity and the prevalence of obesity. Results Physical activity was significantly associated with a lower prevalence of obesity using both WHtR and BMI. Compared to inactive men, odds ratios (ORs) (95% confidence intervals [CIs]) for obesity by WHtR ≥0.50 were 0.69 (0.53–0.89) in active men and 0.76 (0.63–0.91) in very active men (p for trend = 0.007). The ORs (95% CIs) for obesity by BMI ≥25 kg/m2 were 0.78 (0.59–1.03) in active men and 0.82 (0.67–0.99) in very active men (p for trend = 0.060). The ORs (95% CIs) for obesity by BMI ≥30 kg/m2 were 0.40 (0.15–0.98) in active men and 0.90 (0.52–1.56) in very active men (p for trend = 0.978). Compared to inactive women, the ORs (95% CIs) for obesity by WHtR ≥0.50 were 0.94 (0.75–1.18) in active women and 0.84 (0.71–0.998) in very active women (p for trend = 0.046). However, no significant associations were found between physical activity and obesity by BMI in women. Conclusions We found more significant associations between physical activity and obesity defined by WHtR than BMI. However, intervention studies are warranted to investigate and compare causal associations between physical activity and different obesity measures in various populations

  5. Analysis of the Intrinsic βλ,0 Ratio using Spectral Synthesis Models of Composite Stellar Populations

    NASA Astrophysics Data System (ADS)

    Kim, Duho; Jansen, Rolf A.; Windhorst, Rogier A.

    2015-01-01

    Light from galaxies is extincted by dust via scattering and absorbtion. Studying galaxies without correcting for this extinction could lead to incorrect results. Therefore, a careful study of dust correction in the nearby universe should be done first. Tamura et al. (2009) developed an approximate method, dubbed the "βV" method, which corrects for dust extinction on a pixel by pixel basis by comparing the observed and the intrinsic flux ratios of optical and MIR (L~3.5μm) broadband data. A NASA/ADAP funded program "Magellanic Clues to Spatially-resolved Extinction Corrections for Distant Galaxies in the HST/JWST Era" (P.I. : Rolf Jansen), aims to validate and test the limits of the "βV" method by using imagery of the LMC and SMC in various filters and extensive modeling to test assumptions for the intrinsic flux ratios. For the latter, we build spectral energy distribution (SED) models of simple stellar population (SSP), by adopting Starburst99 and BC03 models for young (<9Myr) and old (>100Myr) stellar populations, respectively, and linear combinations of these for intermediate ages. We then construct composite stellar population (CSP) SEDs by combining SSP SEDs as functions of various star formation histories (SFHs). Filter response/throughput curves (V,I,WISE W1(3.4μm), Spitzer IRAC-1 (3.6μm) and L-band) were convolved with the model SEDs to obtain the intrinsic flux ratios (βλ,0). We present the values of βλ,0 as a function of the age and metallicity of stellar populations, and discuss the effect of various SFHs. We also present ranges of βλ,0 values for different types of galaxies.

  6. Comparison of Bolton’s Ratios before and after Treatment in an Iranian Population

    PubMed Central

    Ebadifar, Asghar; Taliee, Rojin

    2013-01-01

    Background and aims The correct relationship of the total mesiodistal width of the mandibular teeth to that of the maxillary teeth (Bolton’s ratios) is among the main factors considered in obtaining an optimal occlusion. The present study was conducted to determining the Bolton’s ratios before and after treatment in skeletal class I patients. Materials and methods In this descriptive analytical study, 200 study casts of 100 patients (including 73 females and 27 males) were selected from 1,700 patient files with fixed, non-extraction orthodontic treatment protocol. The greatest mesiodistal width of teeth was measured using a digital caliper. The total Bolton index (TBI) and anterior Bolton index (ABI) were calculated for subjects and the obtained results were compared with the values reported by Bolton using one-sample t-test. The alterations in these indexes before and after treatment were compared with paired t-test. Results Post-treatment ABI and TBI in patients were 77.35% ± 4.12% and 91.2% ± 1.66%, respectively. No significant difference was detected in ABI and TBI of patients after treatment when compared with the results of Bolton’s study (P > 0.05). However, a significant correlation was observed in values of ABI (P < 0.001) and TBI (P < 0.01) before and after treatment. Conclusion These findings suggest that patients with mild hypodontia have narrower teeth than normal subjects espe-cially in posterior segments, which may have clinical implications during the orthodontic treatment process. PMID:23487005

  7. Modeling level structures of odd-odd deformed nuclei

    SciTech Connect

    Hoff, R.W.; Kern, J.; Piepenbring, R.; Boisson, J.P.

    1985-01-15

    A technique for modeling quasiparticle excitation energies and rotational parameters in odd-odd deformed nuclei has been applied to actinide species where new experimental data have been obtained by use of neutron-capture gamma-ray spectroscopy. The input parameters required for the calculation were derived from empirical data on single-particle excitations in neighboring odd-mass nuclei. Calculated configuration-specific values for the Gallagher-Moszkowski splittings were used. Calculated and experimental level structures for /sup 238/Np, /sup 244/Am, and /sup 250/Bk are compared, as well as those for several nuclei in the rare-earch region. The agreement for the actinide species is excellent, with bandhead energies deviating 22 keV and rotational parameters 5%, on the average. Corresponding average deviations for five rare-earth nuclei are 47 keV and 7%. Several applications of this modeling technique are discussed.

  8. Modeling level structures of odd-odd deformed nuclei

    SciTech Connect

    Hoff, R.W.; Kern, J.; Piepenbring, R.; Boisson, J.P.

    1984-09-07

    A technique for modeling quasiparticle excitation energies and rotational parameters in odd-odd deformed nuclei has been applied to actinide species where new experimental data have been obtained by use of neutron-capture gamma-ray spectroscopy. The input parameters required for the calculation were derived from empirical data on single-particle excitations in neighboring odd-mass nuclei. Calculated configuration-specific values for the Gallagher-Moszkowski splittings were used. Calculated and experimental level structures for /sup 238/Np, /sup 244/Am, and /sup 250/Bk are compared, as well as those for several nuclei in the rare-earth region. The agreement for the actinide species is excellent, with bandhead energies deviating 22 keV and rotational parameters 5%, on the average. Corresponding average deviations for five rare-earth nuclei are 47 keV and 7%. Several applications of this modeling technique are discussed. 18 refs., 5 figs., 4 tabs.

  9. Nonadiabatic effects in odd-odd deformed proton emitters

    SciTech Connect

    Patial, M.; Jain, A. K.; Arumugam, P.; Maglione, E.; Ferreira, L. S.

    2011-11-30

    We present for the first time, the nonadiabatic quasiparticle approach to study proton emission from odd-odd deformed nuclei. Coriolis effects are incorporated in both the parent and daughter wavefunctions and hence our formalism allows us to study their complete role on the decay widths. First results obtained for the nucleus {sup 112}Cs suggest a weak dependance on Coriolis effect. However, we are able to reproduce the experimental half-lives without assuming the exact Nilsson orbital from which the decay proceeds.

  10. Abdominal Obesity Indicators: Waist Circumference or Waist-to-hip Ratio in Malaysian Adults Population

    PubMed Central

    Ahmad, Norfazilah; Adam, Samia Ibrahim Mohamed; Nawi, Azmawati Mohammed; Hassan, Mohd Rohaizat; Ghazi, Hasanain Faisal

    2016-01-01

    Background: Waist circumference (WC) is an accurate and simple measure of abdominal obesity as compared to waist–hip ratio (WHR). The aim of this study was to determine the correlation between body mass index (BMI) with WC and WHR and suggest cutoff points for WC among Rural Malaysian adults. Methods: A cross-sectional study was conducted among 669 respondents from three villages in Tanjung Karang, located in the district of Kuala Selangor. Data collection was carried out by guided questionnaires and anthropometric measures. Results: The prevalence of abdominal obesity for BMI was almost similar for both gender across Caucasian and Asian BMI cutoff points. Based on Caucasian cutoff points, the prevalence of abdominal obesity for WC was 23.8% (male) and 66.4% (female) while for WHR was 6.2% (male) and 54.2% (female). Asian cutoff points gave higher prevalence of abdominal obesity compared to that of WC among male respondents and WHR for both genders. WC showed strong and positive correlation with BMI compared to WHR (in male WC r = 0.78, WHR r = 0.24 and in female WC r = 0.72, WHR r = 0.19; P < 0.001). Receiver operating characteristic curve analysis suggested WC cutoff points of 92.5 cm in men and 85.5 cm in women is the optimal number for detection of abdominal obesity. Conclusions: WC is the best indicator as compared with WHR for abdominal obesity for Malaysian adults. PMID:27330688

  11. Neutrophil to Lymphocyte Ratio and Cardiovascular Disease Incidence in HIV-Infected Patients: A Population-Based Cohort Study

    PubMed Central

    Quiros-Roldan, Eugenia; Raffetti, Elena; Donato, Francesco; Magoni, Michele; Pezzoli, Chiara; Ferraresi, Alice; Brianese, Nigritella; Castelnuovo, Filippo; Focà, Emanuele; Castelli, Francesco

    2016-01-01

    Neutrophil to lymphocyte ratio (NLR) has been shown to predict occurrence of cardiovascular events in the general population. The aim of our study was to evaluate the role of NLR to predict major cardiovascular disease (CVD) events in HIV-infected subjects. We performed a retrospective cohort study of HIV-infected patients residing in the Local Health Authority (LHA) of Brescia, northern Italy, from 2000 to 2012. The incidence of CVD events in HIV-positive patients was compared with that expected in the general population living in the same area, computing standardized incidence ratios (SIRs). To evaluate the predictive role of NLR, univariate and multivariate Cox regression models were applied, computing hazard ratios (HRs). A total of 3766 HIV-infected patients (mean age 38.1 years, 71.3% males) were included (person-years 28768.6). A total of 134 CVD events occurred in 119 HIV-infected patients. A 2-fold increased risk (SIR 2.02) of CVD was found in HIV-infected patients compared to the general population. NLR levels measured at baseline and during follow-up were independently associated with CVD incidence, when also adjusting for both traditional CVD risk factors and HIV-related factors (HR 3.05 for NLR≥ 1.2). The area under the receiver operating characteristics (ROC) curve showed a modest, not statistically significant, increase, from 0.81 to 0.83, with addition of NLR to Framingham risk score model covariates. In conclusion an elevated NLR is a predictor of risk CVD in HIV-infected patients, independently from the traditional CVD risk factors. PMID:27148878

  12. Genetic linkage mapping and transmission ratio distortion in a three-generation four-founder population of Panicum virgatum (L.).

    PubMed

    Li, Guifen; Serba, Desalegn D; Saha, Malay C; Bouton, Joseph H; Lanzatella, Christina L; Tobias, Christian M

    2014-05-01

    Switchgrass (Panicum virgatum L.), a warm season, C4, perennial grass, is one of the predominant grass species of the North American tall grass prairies. It is viewed as a high-potential bioenergy feedstock species because it can produce large amounts of lignocellulosic material with relatively few inputs. The objectives of this project were to develop an advanced switchgrass population and use it for the construction of genetic linkage maps and trait characterization. A three-generation, four-founder population was created and a total of 182 progeny of this advanced population were genotyped, including a mixture of self-pollinated and hybrid individuals. The female map integrated both subpopulations and covered 1629 cM of the switchgrass genome, with an average map length of 91 cM per linkage group. The male map of the hybrid progeny covered 1462 cM, with an average map length of 81 cM per linkage group. Average marker density of the female and male maps was 3.9 and 3.5 cM per marker interval, respectively. Based on the parental maps, the genome length of switchgrass was estimated to be 1776 cM and 1596 cM for the female map and male map, respectively. The proportion of the genome within 5 cM of a mapped locus was estimated to be 92% and 93% for the female map and male map, respectively. Thus, the linkage maps have covered most of the switchgrass genome. The assessment of marker transmission ratio distortion found that 26% of the genotyped markers were distorted from either 1:1 or 3:1 ratios expected for segregation of single dose markers in one or both parents, respectively. Several regions affected by transmission ratio distortion were found, with linkage groups Ib-m and VIIIa-f most affected. PMID:24637352

  13. Genetic Linkage Mapping and Transmission Ratio Distortion in a Three-Generation Four-Founder Population of Panicum virgatum (L.)

    PubMed Central

    Li, Guifen; Serba, Desalegn D.; Saha, Malay C.; Bouton, Joseph H.; Lanzatella, Christina L.; Tobias, Christian M.

    2014-01-01

    Switchgrass (Panicum virgatum L.), a warm season, C4, perennial grass, is one of the predominant grass species of the North American tall grass prairies. It is viewed as a high-potential bioenergy feedstock species because it can produce large amounts of lignocellulosic material with relatively few inputs. The objectives of this project were to develop an advanced switchgrass population and use it for the construction of genetic linkage maps and trait characterization. A three-generation, four-founder population was created and a total of 182 progeny of this advanced population were genotyped, including a mixture of self-pollinated and hybrid individuals. The female map integrated both subpopulations and covered 1629 cM of the switchgrass genome, with an average map length of 91 cM per linkage group. The male map of the hybrid progeny covered 1462 cM, with an average map length of 81 cM per linkage group. Average marker density of the female and male maps was 3.9 and 3.5 cM per marker interval, respectively. Based on the parental maps, the genome length of switchgrass was estimated to be 1776 cM and 1596 cM for the female map and male map, respectively. The proportion of the genome within 5 cM of a mapped locus was estimated to be 92% and 93% for the female map and male map, respectively. Thus, the linkage maps have covered most of the switchgrass genome. The assessment of marker transmission ratio distortion found that 26% of the genotyped markers were distorted from either 1:1 or 3:1 ratios expected for segregation of single dose markers in one or both parents, respectively. Several regions affected by transmission ratio distortion were found, with linkage groups Ib-m and VIIIa-f most affected. PMID:24637352

  14. Use of generalized population ratios to obtain Fe XV line intensities and linewidths at high electron densities

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.; Bhatia, A. K.

    1980-01-01

    A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284-500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t(ij), related to 'taboo' probabilities of Markov chain theory. The t(ij) are here evaluated for a real atomic system, being therefore of potential interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.

  15. Reconstructing the diets of Greek Byzantine populations (6th-15th centuries AD) using carbon and nitrogen stable isotope ratios.

    PubMed

    Bourbou, Chryssi; Fuller, Benjamin T; Garvie-Lok, Sandra J; Richards, Michael P

    2011-12-01

    Documentary evidence and artistic representations have traditionally served as the primary sources of information about Byzantine diet. According to these sources, Byzantine diet was based on grain (primarily wheat and barley), oil, and wine, supplemented with legumes, dairy products, meat, and marine resources. Here, we synthesize and compare the results of stable isotope ratio analyses of eight Greek Byzantine populations (6th-15th centuries AD) from throughout Greece. The δ(13) C and δ(15) N values are tightly clustered, suggesting that all of these populations likely consumed a broadly similar diet. Both inland and coastal Byzantine populations consumed an essentially land-based C(3) diet, significant amounts of animal protein, and possibly some C(4) plants, while no evidence of a general dependence on low-δ(15) N legumes was observed. One interesting result observed in the isotopic data is the evidence for the consumption of marine protein at both coastal sites (a reasonable expectation given their location) and for some individuals from inland sites. This pattern contrasts with previous isotopic studies mainly on prehistoric Greek populations, which have suggested that marine species contributed little, or not at all, to the diet. The possibility that fasting practices contributed to marine protein consumption in the period is discussed, as are possible parallels with published isotope data from western European medieval sites. PMID:21952735

  16. Observation of odd toroidal Alfvén eigenmodes.

    PubMed

    Kramer, G J; Sharapov, S E; Nazikian, R; Gorelenkov, N N; Budny, R V

    2004-01-01

    Experimental evidence is presented for the existence of the theoretically predicted odd toroidicity induced Alfvén eigenmode (TAE) from the simultaneous appearance of odd and even TAEs in a normal shear discharge of the joint European torus. The modes are observed in low central magnetic shear plasmas created by injecting lower hybrid current drive. A fast ion population was created by applying ion cyclotron heating at the high-field side to excite the TAEs. The odd TAEs were identified from their frequency, mode number, and timing relative to the even TAEs. PMID:14753994

  17. Reflection asymmetry in odd-A and odd-odd actinium nuclei

    SciTech Connect

    Ahmad, I.

    1993-09-01

    Theoretical calculations and measurements indicate that octupole correlations are at a maximum in the ground states of the odd-proton nuclei Ac and Pa. It has been expected that odd-odd nuclei should have even larger amount of octupole-octupole correlations. We have recently made measurements on the structure of {sup 224}Ac. Although spin and parity assignments could not be made, two bands starting at 354.1 and 360.0 keV have properties characteristic of reflection asymmetric shape. These two bands have very similar rotational constants and also similar alpha decay rates, which suggest similarity between the wavefunctions of these bands. These signatures provide evidence for octupole correlations in these nuclides.

  18. On Quantizable Odd Lie Bialgebras

    NASA Astrophysics Data System (ADS)

    Khoroshkin, Anton; Merkulov, Sergei; Willwacher, Thomas

    2016-09-01

    Motivated by the obstruction to the deformation quantization of Poisson structures in infinite dimensions, we introduce the notion of a quantizable odd Lie bialgebra. The main result of the paper is a construction of the highly non-trivial minimal resolution of the properad governing such Lie bialgebras, and its link with the theory of so-called quantizable Poisson structures.

  19. Temporal variations of vegetative features, sex ratios and reproductive phenology in a Dictyota dichotoma (Dictyotales, Phaeophyceae) population of Argentina

    NASA Astrophysics Data System (ADS)

    Gauna, M. Cecilia; Cáceres, Eduardo J.; Parodi, Elisa R.

    2013-12-01

    This paper addresses the phenology of a Dictyota dichotoma population from the North Patagonian coasts of Argentina. The morphology of the individuals was characterized, and analyses of the temporal variations of vegetative features, diploid and haploid life cycle generations and sex ratios are provided. Individuals, represented by growing sporophytes and gametophytes, occurred simultaneously throughout the year. Morphological variables showed temporal variation, except the width and height of medullary cells, which did not vary between seasons. All vegetative variables were significantly correlated with daylength. Besides, frond length, frond dry mass and apical and basal branching angles were significantly correlated with seawater temperatures. Vegetative thalli were less abundant than haploid and diploid thalli. Sporophytes were less abundant than male and female gametophytes. Male gametophytes dominated in May, August, October and January, and female gametophytes were more abundant in September, November, December, February and March. The formation of female gametangia showed a significant correlation with daylength, and the highest number of gametangia was registered in spring. In general, the male/female sex ratio varied between 1:2 and 1:1. Apical regions were more fertile than basal regions. Our data about frequency in the formation of reproductive structures and male/female ratios are the first recorded in the Dictyota genus and thus could not be compared with populations from other regions of the world. Significant morphological variation was observed in thalli of both life cycle generations, regarding length and dry mass, number of primary branches and branching basal angle. In general, all variables analyzed varied seasonally except cortical cell width.

  20. Age at sexual maturity, sex ratio, fecundity, and longevity of isolated headwater populations of Westslope cutthroat trout

    USGS Publications Warehouse

    Downs, Christopher C.; White, R.G.; Shepard, B.B.

    1997-01-01

    We sampled 19 isolated headwater populations of westslope cutthroat trout Oncorhynchus clarki lewisi in Montana to provide estimates of fecundity, longevity, sex ratio, and age at sexual maturity. Fecundity was estimated for 31 fish collected from two streams in the upper Missouri River drainage. Females smaller than 149 mm fork length (FL) were generally immature and their fecundities could not be estimated. Mean fecundities (SD) were 227 eggs (41.1) for 150-174-mm fish, 346 eggs (85.6) for 175-199-mm fish, and 459 eggs (150.8) for 200-mm and larger fish. A linear regression model (two stream samples combined) to predict fecundity (E) from fork length was developed (E = -494.9 + 4.4.FL: r2 = 0.51, P < 0.001) for westslope cutthroat trout in the upper Missouri River drainage. Regression slopes of fecundity against fish length differed significantly (P < 0.01) between these and some of the previously studied populations. Steeper slopes were associated with lacustrine-adfluvial populations. The average sex ratio was 1.3 males per female across all sampled streams. Males began to mature sexually at age 2 and all were mature by age 4. Some females (27%) were sexually mature at age 3 and most of them (93%) were mature by age 5. Length was a better predictor of sexual maturity than age. Males matured at 110-160 mm and females at 150-180 mm FL. The maximum estimated age was 8 years based on otoliths from 475 fish collected from our 19 study streams and 14 additional streams.

  1. Excited states of the odd-odd nucleus 230Pa

    NASA Astrophysics Data System (ADS)

    Kotthaus, T.; Reiter, P.; Hess, H.; Kalkühler, M.; Wendt, A.; Wiens, A.; Hertenberger, R.; Morgan, T.; Thirolf, P. G.; Wirth, H.-F.; Faestermann, T.

    2013-04-01

    The completely unknown spectrum of excited states of the odd-odd nucleus 230Pa was studied employing the one-neutron transfer reaction 231Pa(d,t)230Pa at a beam energy of 22 MeV. The excitation energy and the cross section were measured for, in total, 81 states below 1.4 MeV. Level assignments of these states are based on a semiempirical model and comparison with theoretical predictions, based on distorted-wave Born approximation (DWBA) calculations for the cross sections. For 12 rotational bands the band-head energy and the rotational parameter are determined. The K quantum numbers and the Nilsson configurations are established. Empirical values for the Gallagher-Moszkowski splittings and for Newby shifts are obtained.

  2. Carbohydrate-to-Insulin Ratio in a Mediterranean Population of Type 1 Diabetic Patients on Continuous Subcutaneous Insulin Infusion Therapy

    PubMed Central

    Alcántara-Aragón, Valeria; Gonzalez, Cintia; Corcoy, Rosa; Ubeda, Justa; Chico, Ana

    2014-01-01

    Background: The carbohydrate-to-insulin ratio (CIR) is initially calculated from the total daily insulin dose (TDID). However, CIR likely presents variations owing to different population characteristics and intraday variations not being taken into account by most formulas. No information is available concerning the Mediterranean population. We investigated the CIR used by patients with type 1 diabetes (T1DM) using continuous subcutaneous insulin infusion (CSII) therapy in a Mediterranean area, to identify possible intraday variations and establish an adequate formula to calculate CIR. Methods: Data from 170 T1DM patients from Barcelona were obtained retrospectively from the Spanish National Registry of CSII Therapy (SNR-CSII). Theoretical CIR was calculated using the formula: 500 divided by TDID. This theoretical CIR was compared to the real CIR. Results: The real CIR was also compared between main meals. Patients with HbA1c < 7% (n = 44) were considered a reference group for accurate bolus calculation and were analyzed as a subgroup. The real CIR used was 11.5 g/UI for breakfast, 12 g/UI for lunch, and 13.3 g/UI for dinner. CIR obtained by the 500/TDID formula for all meals was 15.5 g/UI. We obtained similar results for the group with HbA1c < 7%. The real CIR differed significantly from the theoretical CIR values and between breakfast and the other main meals (P < .005). Conclusions: CIR in our population was significantly lower for breakfast than for other meals. CIR using the 500/TDID formula underestimated prandial insulin requirements. A calculation of 350/TDID for breakfast and 400/TDID for lunch and dinner would be more appropriate for this population. PMID:25519294

  3. Gene drive through a landscape: Reaction-diffusion models of population suppression and elimination by a sex ratio distorter.

    PubMed

    Beaghton, Andrea; Beaghton, Pantelis John; Burt, Austin

    2016-04-01

    Some genes or gene complexes are transmitted from parents to offspring at a greater-than-Mendelian rate, and can spread and persist in populations even if they cause some harm to the individuals carrying them. Such genes may be useful for controlling populations or species that are harmful. Driving-Y chromosomes may be particularly potent in this regard, as they produce a male-biased sex ratio that, if sufficiently extreme, can lead to population elimination. To better understand the potential of such genes to spread over a landscape, we have developed a series of reaction-diffusion models of a driving-Y chromosome in 1-D and radially-symmetric 2-D unbounded domains. The wild-type system at carrying capacity is found to be unstable to the introduction of driving-Y males for all models investigated. Numerical solutions exhibit travelling wave pulses and fronts, and analytical and semi-analytical solutions for the asymptotic wave speed under bounded initial conditions are derived. The driving-Y male invades the wild-type equilibrium state at the front of the wave and completely replaces the wild-type males, leaving behind, at the tail of the wave, a reduced- or zero-population state of females and driving-Y males only. In our simplest model of a population with one life stage and density-dependent mortality, wave speed depends on the strength of drive and the diffusion rate of Y-drive males, and is independent of the population dynamic consequences (suppression or elimination). Incorporating an immobile juvenile stage of fixed duration into the model reduces wave speed approximately in proportion to the relative time spent as a juvenile. If females mate just once in their life, storing sperm for subsequent reproduction, then wave speed depends on the movement of mated females as well as Y-drive males, and may be faster or slower than in the multiple-mating model, depending on the relative duration of juvenile and adult life stages. Numerical solutions are shown for

  4. Impact of PCB and p,p′-DDE Contaminants on Human Sperm Y:X Chromosome Ratio: Studies in Three European Populations and the Inuit Population in Greenland

    PubMed Central

    Tiido, Tarmo; Rignell-Hydbom, Anna; Jönsson, Bo A.G.; Giwercman, Yvonne Lundberg; Pedersen, Henning S.; Wojtyniak, Bogdan; Ludwicki, Jan K.; Lesovoy, Vladimir; Zvyezday, Valentyna; Spano, Marcello; Manicardi, Gian-Carlo; Bizzaro, Davide; Bonefeld-Jørgensen, Eva C.; Toft, Gunnar; Bonde, Jens Peter; Rylander, Lars; Hagmar, Lars; Giwercman, Aleksander

    2006-01-01

    Objective Recent studies indicate that persistent organohalogen pollutants (POPs) may contribute to sex ratio changes in offspring of exposed populations. Our aim in the present study was to investigate whether exposure to 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB-153) and dichlorodiphenyldichloroethene (p,p′-DDE) affects sperm Y:X chromosome distribution. Subjects and methods We obtained semen and blood for analysis of PCB-153 and p,p′-DDE levels from 547 men from Sweden, Greenland, Poland (Warsaw), and Ukraine (Kharkiv), with regionally different levels of POP exposure. The proportion of Y- and X-chromosome–bearing sperm in the semen samples was determined by two-color fluorescence in situ hybridization analysis. Results Swedish and Greenlandic men had on average significantly higher proportions of Y sperm (in both cohorts, 51.2%) and correspondingly higher lipid-adjusted concentrations of PCB-153 (260 ng/g and 350 ng/g, respectively) compared with men from Warsaw (50.3% and 22 ng/g) and Kharkiv (50.7% and 54 ng/g). In the Swedish cohort, log-transformed PCB-153 and log-transformed p,p′-DDE variables were significantly positively associated with Y-chromosome fractions (p-values 0.04 and < 0.001, respectively). On the contrary, in the Polish cohort PCB-153 correlated negatively with the proportion of Y-bearing fraction of spermatozoa (p = 0.008). Conclusions The present study indicates that POP exposure might be involved in changing the proportion of ejaculated Y-bearing spermatozoa in human populations. Intercountry differences, with different exposure situations and doses, may contribute to varying Y:X chromosome ratios. PMID:16675426

  5. Plant GABA:proline ratio modulates dissemination of the virulence Ti plasmid within the Agrobacterium tumefaciens hosted population.

    PubMed

    Lang, Julien; Faure, Denis

    2016-05-01

    Accumulation of amino acids is a common plant response to several biotic and abiotic stresses, even if the roles of these accumulations remain often poorly understood. In a recent study we measured the levels of different amino acids in tumors of Arabidopsis thaliana induced by the phytopathogen Agrobacterium tumefaciens and correlated these data with changes of gene expressions in both organisms. This led to the demonstration that the non-protein amino acid GABA plays an important role for the adaptation of the bacteria to the plant tumor environment, and especially in the control of the virulent Ti plasmid dissemination. Here we present a model that describes how different GABA:proline ratios in the A. thaliana host may have different impacts on the conjugation of A. tumefaciens Ti plasmid, and advance the view that the amino acid metabolism of plant hosts could be critical for the propagation of the virulence genes in A. tumefaciens populations. PMID:27110651

  6. Simultaneous failure of two sex-allocation invariants: implications for sex-ratio variation within and between populations

    PubMed Central

    Rodrigues, António M. M.; Gardner, Andy

    2015-01-01

    Local mate competition (LMC) occurs when male relatives compete for mating opportunities, and this may favour the evolution of female-biased sex allocation. LMC theory is among the most well developed and empirically supported topics in behavioural ecology, clarifies links between kin selection, group selection and game theory, and provides among the best quantitative evidence for Darwinian adaptation in the natural world. Two striking invariants arise from this body of work: the number of sons produced by each female is independent of both female fecundity and also the rate of female dispersal. Both of these invariants have stimulated a great deal of theoretical and empirical research. Here, we show that both of these invariants break down when variation in female fecundity and limited female dispersal are considered in conjunction. Specifically, limited dispersal of females following mating leads to local resource competition (LRC) between female relatives for breeding opportunities, and the daughters of high-fecundity mothers experience such LRC more strongly than do those of low-fecundity mothers. Accordingly, high-fecundity mothers are favoured to invest relatively more in sons, while low-fecundity mothers are favoured to invest relatively more in daughters, and the overall sex ratio of the population sex ratio becomes more female biased as a result. PMID:26085590

  7. Past primary sex-ratio estimates of 4 populations of Loggerhead sea turtle based on TSP durations.

    NASA Astrophysics Data System (ADS)

    Monsinjon, Jonathan; Kaska, Yakup; Tucker, Tony; LeBlanc, Anne Marie; Williams, Kristina; Rostal, David; Girondot, Marc

    2016-04-01

    Ectothermic species are supposed to be strongly affected by climate change and particularly those that exhibit temperature-dependent sex-determination (TSD). Actually, predicting the embryonic response of such organism to incubation-temperature variations in natural conditions remains challenging. In order to assess the vulnerability of sea turtles, primary sex-ratio estimates should be produced at pertinent ecological time and spatial scales. Although information on this important demographic parameter is one of the priorities for conservation purpose, accurate methodology to produce such an estimate is still lacking. The most commonly used method invocates incubation duration as a proxy for sex-ratio. This method is inappropriate because temperature influences incubation duration during all development whereas sex is influenced by temperature during only part of development. The thermosensitive period of development for sex determination (TSP) lies in the middle third of development. A model of embryonic growth must be used to define precisely the position of the TSP at non-constant incubation temperatures. The thermal reaction norm for embryonic growth rate have been estimated for 4 distinct populations of the globally distributed and threatened marine turtle Caretta caretta. A thermal reaction norm describes the pattern of phenotypic expression of a single genotype across a range of temperatures. Moreover, incubation temperatures have been reconstructed for the last 35 years using a multi-correlative model with climate temperature. After development of embryos have been modelled, we estimated the primary sex-ratio based on the duration of the TSP. Our results suggests that Loggerhead sea turtles nesting phenology is linked with the period within which both sexes can be produced in variable proportions. Several hypotheses will be discussed to explain why Caretta caretta could be more resilient to climate change than generally thought for sex determination.

  8. Population structure, sex ratio and growth of the seabob shrimp Xiphopenaeus kroyeri (Decapoda, Penaeidae) from coastal waters of southern Brazil

    PubMed Central

    Grabowski, Raphael Cezar; Simões, Sabrina Morilhas; Castilho, Antonio Leão

    2014-01-01

    Abstract This study evaluated the growth and population structure of Xiphopenaeus kroyeri in Babitonga Bay, southern Brazil. Monthly trawls were conducted from July 2010 through June 2011, using a shrimp boat outfitted with double-rig nets, at depths from 5 to 17 m. Differences from the expected 0.5 sex ratio were determined by applying a Binomial test. A von Bertalanffy growth model was used to estimate the individual growth, and longevity was calculated using its inverted formula. A total of 4,007 individuals were measured, including 1,106 juveniles (sexually immature) and 2,901 adults. Females predominated in the larger size classes. Males and females showed asymptotic lengths of 27.7 mm and 31.4 mm, growth constants of 0.0086 and 0.0070 per day, and longevities of 538 and 661 days, respectively. The predominance of females in larger size classes is the general rule in species of Penaeidae. The paradigm of latitudinal-effect does not appear to apply to seabob shrimp on the southern Brazilian coast, perhaps because of the small proportion of larger individuals, the occurrence of cryptic species, or the intense fishing pressure in this region. The longevity values are within the general range for species of Penaeidae. The higher estimates for longevity in populations at lower latitudes may have occurred because of the growth constants observed at these locations, resulting in overestimation of this parameter. PMID:25561841

  9. Persistence of an extreme male-biased adult sex ratio in a natural population of polyandrous bird.

    PubMed

    Kosztolányi, A; Barta, Z; Küpper, C; Székely, T

    2011-08-01

    In a number of insects, fishes and birds, the conventional sex roles are reversed: males are the main care provider, whereas females focus on matings. The reversal of typical sex roles is an evolutionary puzzle, because it challenges the foundations of sex roles, sexual selection and parental investment theory. Recent theoretical models predict that biased parental care may be a response to biased adult sex ratios (ASRs). However, estimating ASR is challenging in natural populations, because males and females often have different detectabilities. Here, we use demographic modelling with field data from 2101 individuals, including 579 molecularly sexed offspring, to provide evidence that ASR is strongly male biased in a polyandrous bird with male-biased care. The model predicts 6.1 times more adult males than females (ASR=0.860, proportion of males) in the Kentish plover Charadrius alexandrinus. The extreme male bias is consistent between years and concordant with experimental results showing strongly biased mating opportunity towards females. Based on these results, we conjecture that parental sex-role reversal may occur in populations that exhibit extreme male-biased ASR. PMID:21749544

  10. Stable nitrogen and carbon isotope ratios indicate traditional and market food intake in an indigenous circumpolar population.

    PubMed

    Nash, Sarah H; Bersamin, Andrea; Kristal, Alan R; Hopkins, Scarlett E; Church, Rebecca S; Pasker, Renee L; Luick, Bret R; Mohatt, Gerald V; Boyer, Bert B; O'Brien, Diane M

    2012-01-01

    The transition of a society from traditional to market-based diets (termed the nutrition transition) has been associated with profound changes in culture and health. We are developing biomarkers to track the nutrition transition in the Yup'ik Eskimo population of Southwest Alaska based on naturally occurring variations in the relative abundances of carbon and nitrogen stable isotopes (δ(15)N and δ(13)C values). Here, we provide three pieces of evidence toward the validation of these biomarkers. First, we analyzed the δ(15)N and δ(13)C values of a comprehensive sample of Yup'ik foods. We found that δ(15)N values were elevated in fish and marine mammals and that δ(13)C values were elevated in market foods containing corn or sugar cane carbon. Second, we evaluated the associations between RBC δ(15)N and δ(13)C values and self-reported measures of traditional and market food intake (n = 230). RBC δ(15)N values were correlated with intake of fish and marine mammals (r = 0.52; P < 0.0001). RBC δ(13)C values were correlated with intake of market foods made from corn and sugar cane (r = 0.46; P < 0.0001) and total market food intake (r = 0.46; P < 0.0001). Finally, we assessed whether stable isotope ratios captured population-level patterns of traditional and market intake (n = 1003). Isotopic biomarkers of traditional and market intake were associated with age, community location, sex, and cultural identity. Self-report methods showed variations by age and cultural identity only. Thus, stable isotopes show potential as biomarkers for monitoring dietary change in indigenous circumpolar populations. PMID:22157543

  11. Exploring the active galactic nuclei population with extreme X-ray-to-optical flux ratios (fx/fo > 50)

    NASA Astrophysics Data System (ADS)

    Della Ceca, R.; Carrera, F. J.; Caccianiga, A.; Severgnini, P.; Ballo, L.; Braito, V.; Corral, A.; Del Moro, A.; Mateos, S.; Ruiz, A.; Watson, M. G.

    2015-03-01

    The cosmic history of the growth of supermassive black holes in galactic centres parallels that of star formation in the Universe. However, an important fraction of this growth occurs inconspicuously in obscured objects, where ultraviolet/optical/near-infrared emission is heavily obscured by dust. Since the X-ray flux is less attenuated, a high X-ray-to-optical flux ratio (fx/fo) is expected to be an efficient tool to find out these obscured accreting sources. We explore here via optical spectroscopy, X-ray spectroscopy and infrared photometry the most extreme cases of this population (those with fx/fo > 50, EXO50 sources hereafter), using a well-defined sample of seven X-ray sources extracted from the 2XMM catalogue. Five EXO50 sources (˜70 per cent of the sample) in the bright flux regime explored by our survey (f(2-10 keV) ≥ 1.5 × 10-13 erg cm-2 s-1) are associated with obscured AGN (NH > 1022 cm-2), spanning a redshift range between 0.75 and 1 and characterized by 2-10 keV intrinsic luminosities in the QSO regime (e.g. well in excess to 1044 erg s-1). We did not find compelling evidence of Compton thick active galacic nuclei (AGN). Overall, the EXO50 type 2 QSOs do not seem to be different from standard X-ray-selected type 2 QSOs in terms of nuclear absorption; a very high AGN/host galaxy ratio seems to play a major role in explaining their extreme properties. Interestingly, three out of five EXO50 type 2 QSO objects can be classified as extreme dust-obscured galaxies (EDOGs, f24 μm/fR ≥ 2000), suggesting that a very high AGN/host ratios (along with the large amount of dust absorption) could be the natural explanation also for a part of the EDOG population. The remaining two EXO50 sources are classified as BL Lac objects, having rather extreme properties, and which are good candidates for TeV emission.

  12. Pollen limitation and Allee effect related to population size and sex ratio in the endangered Ottelia acuminata (Hydrocharitaceae): implications for conservation and reintroduction.

    PubMed

    Xia, J; Lu, J; Wang, Z X; Hao, B B; Wang, H B; Liu, G H

    2013-03-01

    Small populations may suffer more severe pollen limitation and result in Allee effects. Sex ratio may also affect pollination and reproduction success in dioecious species, which is always overlooked when performing conservation and reintroduction tasks. In this study, we investigated whether and how population size and sex ratio affected pollen limitation and reproduction in the endangered Ottelia acuminata, a dioecious submerged species. We established experimental plots with increasing population size and male sex ratio. We observed insect visitation, estimated pollen limitation by hand-pollinations and counted fruit set and seed production per fruit. Fruit set and seed production decreased significantly in small populations due to pollinator scarcity and thus suffered more severe pollen limitation. Although frequently visited, female-biased larger populations also suffered severe pollen limitation due to few effective visits and insufficient pollen availability. Rising male ratio enhanced pollination service and hence reproduction. Unexpectedly, pollinator preferences did not cause reduced reproduction in male-biased populations because of high pollen availability. However, reproductive outputs showed more variability in severe male-biased populations. Our results revealed two component Allee effects in fruit set and seed production, mediated by pollen limitation in O. acuminata. Moreover, reproduction decreased significantly in larger female-biased populations, increasing the risk of an Allee effect. PMID:22963276

  13. Evidence for Cross-Tolerance to Nutrient Deficiency in Three Disjunct Populations of Arabidopsis lyrata ssp. lyrata in Response to Substrate Calcium to Magnesium Ratio

    PubMed Central

    Veatch-Blohm, Maren E.; Roche, Bernadette M.; Campbell, MaryJean

    2013-01-01

    Species with widespread distributions that grow in varied habitats may consist of ecotypes adapted to a particular habitat, or may exhibit cross-tolerance that enables them to exploit a variety of habitats. Populations of Arabidopsis lyrata ssp. lyrata (L.) O’Kane & Al-Shehbaz grow in a wide variety of edaphic settings including serpentine soil, limestone sand, and alluvial flood plains. While all three of these environments share some stressors, a crucial difference among these environments is soil calcium to magnesium ratio, which ranges from 25∶1 in the limestone sand to 0.2∶1 in serpentine soil. The three populations found on these substrates were subjected to three different Ca to Mg ratios under controlled environmental conditions during germination and rosette growth. Response to Ca to Mg ratio was evaluated through germination success and radicle growth rate, rosette growth rate, and the content of Ca and Mg in the rosette. All three populations were particularly efficient in fueling growth under nutrient deficiency, with the highest nutrient efficiency ratio for Ca under Ca deficiency and for Mg under Mg deficiency. Although the serpentine population had significantly higher leaf Ca to Mg ratio than the limestone or flood plain populations under all three Ca to Mg ratios, this increase did not result in any advantage in growth or appearance of the serpentine plants, during early life stages before the onset of flowering, even in the high Mg substrate. The three populations showed no population by substrate interaction for any of the parameters measured indicating that these populations may have cross-tolerance to substrate Ca to Mg ratio. PMID:23650547

  14. Age estimation in an Indian population using pulp/tooth volume ratio of mandibular canines obtained from cone beam computed tomography.

    PubMed

    Jagannathan, N; Neelakantan, P; Thiruvengadam, C; Ramani, P; Premkumar, P; Natesan, A; Herald, J S; Luder, H U

    2011-07-01

    The present study assessed the suitability of pulp/tooth volume ratio of mandibular canines for age prediction in an Indian population. Volumetric reconstruction of scanned images of mandibular canines from 140 individuals (aged ten - 70 years), using computed tomography was used to measure pulp and tooth volumes. Age calculated using a formula reported earlier for a Belgian sample, resulted in errors > ten years in almost 86% of the study population. The regression equation obtained for the Indian population: Age = 57.18 + (- 413.41 x pulp/tooth volume ratio), was applied to an independent control group (n = 48), and this resulted in mean absolute errors of 8.54 years which was significantly (p < 0.05) lower than those derived with the Belgian formula. The pulp/tooth volume ratio is a useful indicator of age, although correlations may vary in different populations and hence, specific formulae should be applied for the estimates. PMID:21841263

  15. Modeling degradation ratios and nutrient availability of anthocyanidin-accumulating Lc-alfalfa populations in dairy cows.

    PubMed

    Jonker, A; Gruber, M Y; Wang, Y; Coulman, B; Azarfar, A; McKinnon, J J; Christensen, D A; Yu, P

    2011-03-01

    Dairy cattle eating fresh or ensiled alfalfa as the main portion of their diet often have low protein efficiency because of the rapid initial rate of ruminal protein degradation of fresh and ensiled alfalfa. Ruminal protein degradation of alfalfa might be reduced by introducing a gene that stimulates the accumulation of mono- or polymeric anthocyanidins in alfalfa. The objectives of this study were to fractionate protein and carbohydrates by in situ and chemical approaches, to evaluate in situ ruminal degradation characteristics and synchronization ratios, to determine protein availability to dairy cattle using the 2007 digestible intestinal protein/rumen-degraded protein balance (DVE/OEB) protein system, and to determine net energy for lactation using the Dutch net energy for lactation (VEM) system for 3 newly developed transgenic winter hardy anthocyanidin-accumulating T(1)Lc-alfalfa populations. These T(1)Lc-alfalfa populations, called (T1)BeavLc1, (T1)RambLc3, and (T1)RangLc4, had an average anthocyanidin accumulation of 163.4 μg/g of DM, whereas AC Grazeland (selected for a low initial rate of degradation) did not accumulate anthocyanidin. The basic chemical composition of the original samples, soluble and potentially degradable fractions, and degradation characteristics of crude protein and carbohydrates were similar in T(1)Lc-alfalfa and AC Grazeland. The undegradable in situ crude protein and neutral detergent fiber fraction had 1.3% lower CP and 4.8% lower CHO, respectively, in T(1)Lc-alfalfa compared with the amounts in AC Grazeland. The T(1)Lc-alfalfa had a 0.34 MJ/kg of DM higher calculated net energy for lactation and 1.9% of CP higher buffer soluble protein compared with that in AC Grazeland. By the protein evaluation model, it was predicted that T(1)Lc-alfalfa tended to have 11.9, 6.9, and 8.4 g/kg of DM higher rumen degradable protein, OEB, and intestinal available protein, respectively, compared with the amounts in AC Grazeland. The hourly OEB

  16. Biased sex ratio and low population density increase male mating success in the bug Nysius huttoni (Heteroptera: Lygaeidae).

    PubMed

    Wang, Qiao; He, Xiong Zhao; Yang, Linghuan; Hedderley, Duncan; Davis, Lorraine K

    2009-01-01

    Demographic factors such as operational sex ratio (OSR) and local population density (LPD) are temporally and spatially dynamic in the natural environment but the influence of these variables on male mating success and the mechanisms behind it are still poorly understood and highly controversial. Here, we manipulated the OSR and LPD of a seed bug, Nysius huttoni, and carried out a series of mating trials to test how these variables affected male mating success. The two demographic factors had no significant interactions, suggesting that they affect male mating success independently in N. huttoni. In this species male mating success was significantly higher in both male- and female-biased OSR than in even OSR. It is suggested that, in male-biased OSR, the increased intensity of competition and interference does not result in lower male mating success; rather, males may make more effort in courting and females may have more chance to encounter better males, resulting in higher male mating success. In female-biased OSR, females may become less choosy and less likely to reject male mating attempt, leading to the higher male mating success. Lower male mating success in N. huttoni in high LPD may be due to increased interference between males and/or delayed female receptiveness for mating. OSR had a stronger effect on male mating success than LPD in N. huttoni, suggesting that OSR and LPD affect mating success in different ways and intensities. PMID:18839127

  17. Biased sex ratio and low population density increase male mating success in the bug Nysius huttoni (Heteroptera: Lygaeidae)

    NASA Astrophysics Data System (ADS)

    Wang, Qiao; He, Xiong Zhao; Yang, Linghuan; Hedderley, Duncan; Davis, Lorraine K.

    2009-01-01

    Demographic factors such as operational sex ratio (OSR) and local population density (LPD) are temporally and spatially dynamic in the natural environment but the influence of these variables on male mating success and the mechanisms behind it are still poorly understood and highly controversial. Here, we manipulated the OSR and LPD of a seed bug, Nysius huttoni, and carried out a series of mating trials to test how these variables affected male mating success. The two demographic factors had no significant interactions, suggesting that they affect male mating success independently in N. huttoni. In this species male mating success was significantly higher in both male- and female-biased OSR than in even OSR. It is suggested that, in male-biased OSR, the increased intensity of competition and interference does not result in lower male mating success; rather, males may make more effort in courting and females may have more chance to encounter better males, resulting in higher male mating success. In female-biased OSR, females may become less choosy and less likely to reject male mating attempt, leading to the higher male mating success. Lower male mating success in N. huttoni in high LPD may be due to increased interference between males and/or delayed female receptiveness for mating. OSR had a stronger effect on male mating success than LPD in N. huttoni, suggesting that OSR and LPD affect mating success in different ways and intensities.

  18. Ratios between acute aquatic toxicity and effects on population growth rates in relation to toxicant mode of action

    SciTech Connect

    Roex, E.W.M.; Gestel, C.A.M. Van; Wezel, A.P. Van; Straalen, N.M. Van

    2000-03-01

    Environmental risk assessment of chemicals is mostly based on the results of standardized toxicity tests. To obtain environmental quality criteria, extrapolation factors are used that depend on the amount and quality of available data. These extrapolation factors do not, however, take into account the mode of action of the compound tested or the life history of the test organism. In this study, the authors analyzed the variability in acute-to-chronic ratios (ACRs) for various chemicals in relation to their mode of action. Chemicals were classified as nonpolar narcotics, polar narcotics, specifically acting compounds, and heavy metals. As an acute endpoint, the LC50 was used; as a chronic endpoint, the lowest test concentration at which the natural rate of population increase (r) is affected, or LOEC(r), was used. Data were derived from the on-line literature. Nonpolar narcotic chemicals demonstrate the smallest variation in ACRs, and acute tests can be used to derive chronic endpoints for this class. For the other classes, the variation in ACRs is larger. Fish species especially show a relatively large ACR. For heavy metals, differences in the mode of action may play an important role in explaining differences in ACRs. For the other three classes, however, it is less reliable to predict chronic toxicity using the results of acute tests. In general, differences in species sensitivity rather than in mode of action for the chemical seem to determine differences in ACRs.

  19. Use of prior odds for missing persons identifications

    PubMed Central

    2011-01-01

    Identification of missing persons from mass disasters is based on evaluation of a number of variables and observations regarding the combination of features derived from these variables. DNA typing now is playing a more prominent role in the identification of human remains, and particularly so for highly decomposed and fragmented remains. The strength of genetic associations, by either direct or kinship analyses, is often quantified by calculating a likelihood ratio. The likelihood ratio can be multiplied by prior odds based on nongenetic evidence to calculate the posterior odds, that is, by applying Bayes' Theorem, to arrive at a probability of identity. For the identification of human remains, the path creating the set and intersection of variables that contribute to the prior odds needs to be appreciated and well defined. Other than considering the total number of missing persons, the forensic DNA community has been silent on specifying the elements of prior odds computations. The variables include the number of missing individuals, eyewitness accounts, anthropological features, demographics and other identifying characteristics. The assumptions, supporting data and reasoning that are used to establish a prior probability that will be combined with the genetic data need to be considered and justified. Otherwise, data may be unintentionally or intentionally manipulated to achieve a probability of identity that cannot be supported and can thus misrepresent the uncertainty with associations. The forensic DNA community needs to develop guidelines for objectively computing prior odds. PMID:21707977

  20. Effects of thyroid endocrine manipulation on sex-related gene expression and population sex ratios in Zebrafish.

    PubMed

    Sharma, Prakash; Tang, Song; Mayer, Gregory D; Patiño, Reynaldo

    2016-09-01

    Thyroid hormone reportedly induces masculinization of genetic females and goitrogen treatment delays testicular differentiation (ovary-to-testis transformation) in genetic males of Zebrafish. This study explored potential molecular mechanisms of these phenomena. Zebrafish were treated with thyroxine (T4, 2nM), goitrogen [methimazole (MZ), 0.15mM], MZ (0.15mM) and T4 (2nM) (rescue treatment), or reconstituted water (control) from 3 to 33days postfertilization (dpf) and maintained in control water until 45dpf. Whole fish were collected during early (25dpf) and late (45dpf) testicular differentiation for transcript abundance analysis of selected male (dmrt1, amh, ar) and female (cyp19a1a, esr1, esr2a, esr2b) sex-related genes by quantitative RT-PCR, and fold-changes relative to control values were determined. Additional fish were sampled at 45dpf for histological assessment of gonadal sex. The T4 and rescue treatments caused male-biased populations, and T4 alone induced precocious puberty in ∼50% of males. Male-biased sex ratios were accompanied by increased expression of amh and ar and reduced expression of cyp19a1a, esr1, esr2a, and esr2b at 25 and 45dpf and, unexpectedly, reduced expression of dmrt1 at 45dpf. Goitrogen exposure increased the proportion of individuals with ovaries (per previous studies interpreted as delay in testicular differentiation of genetic males), and at 25 and 45dpf reduced the expression of amh and ar and increased the expression of esr1 (only at 25dpf), esr2a, and esr2b. Notably, cyp19a1a transcript was reduced but via non-thyroidal pathways (not restored by rescue treatment). In conclusion, the masculinizing activity of T4 at the population level may be due to its ability to inhibit female and stimulate male sex-related genes in larvae, while the inability of MZ to induce cyp19a1a, which is necessary for ovarian differentiation, may explain why its "feminizing" activity on gonadal sex is not permanent. PMID:27255368

  1. Effects of thyroid endocrine manipulation on sex-related gene expression and population sex ratios in Zebrafish

    USGS Publications Warehouse

    Sharma, Prakash; Tang, Song; Mayer, Gregory D.; Patino, Reynaldo

    2016-01-01

    Thyroid hormone reportedly induces masculinization of genetic females and goitrogen treatment delays testicular differentiation (ovary-to-testis transformation) in genetic males of Zebrafish. This study explored potential molecular mechanisms of these phenomena. Zebrafish were treated with thyroxine (T4, 2 nM), goitrogen [methimazole (MZ), 0.15 mM], MZ (0.15 mM) and T4 (2 nM) (rescue treatment), or reconstituted water (control) from 3 to 33 days postfertilization (dpf) and maintained in control water until 45 dpf. Whole fish were collected during early (25 dpf) and late (45 dpf) testicular differentiation for transcript abundance analysis of selected male (dmrt1, amh, ar) and female (cyp19a1a, esr1, esr2a, esr2b) sex-related genes by quantitative RT-PCR, and fold-changes relative to control values were determined. Additional fish were sampled at 45 dpf for histological assessment of gonadal sex. The T4 and rescue treatments caused male-biased populations, and T4 alone induced precocious puberty in ∼50% of males. Male-biased sex ratios were accompanied by increased expression of amh and ar and reduced expression of cyp19a1a, esr1, esr2a, and esr2b at 25 and 45 dpf and, unexpectedly, reduced expression of dmrt1 at 45 dpf. Goitrogen exposure increased the proportion of individuals with ovaries (per previous studies interpreted as delay in testicular differentiation of genetic males), and at 25 and 45 dpf reduced the expression of amh and ar and increased the expression of esr1 (only at 25 dpf), esr2a, and esr2b. Notably, cyp19a1a transcript was reduced but via non-thyroidal pathways (not restored by rescue treatment). In conclusion, the masculinizing activity of T4 at the population level may be due to its ability to inhibit female and stimulate male sex-related genes in larvae, while the inability of MZ to induce cyp19a1a, which is necessary for ovarian differentiation, may explain why its “feminizing” activity on gonadal

  2. Birth Order and Sibling Sex Ratio in a Population with High Fertility: Are Turkish Male to Female Transsexuals Different?

    PubMed

    Bozkurt, Ali; Bozkurt, Ozlem Hekim; Sonmez, Ipek

    2015-07-01

    Western studies have consistently found that androphilic (sexually attracted to men) male-to-female transsexuals have a later birth order and a relative excess of brothers compared with appropriate control participants. However, non-Western studies on birth order and sibling sex ratio in androphilic males (transsexual or non-transsexual) are rare. The objective of the study was to test the hypothesis that androphilic male-to-female transsexuals have a late birth order and a relative excess of brothers in a non-Western culture with a higher fertility rate. The participants were 60 androphilic male-to-female transsexuals and 61 male heterosexual controls. The transsexual participants had significantly more older brothers than the control participants, but the groups did not differ in their numbers of older sisters, younger brothers, or younger sisters. The foregoing pattern is usually referred to as the "fraternal birth order effect." Slater's and Berglin's Indexes both showed that the mean birth order of the control participants was very close to that expected from a random sample drawn from a demographically stable population whereas the mean birth order of the transsexual participants was later. A measure of sibship composition, brothers/all siblings, showed that the transsexual group had a higher proportion of male siblings compared with the control group. In conclusion, the present study found that Turkish androphilic male-to-female transsexuals show the same high fraternal birth order that has been found in comparable androphilic samples in Western Europe, North America, and the South Pacific, which suggests a common underlying biological causal mechanism. PMID:25351529

  3. Predictors of Metabolic Syndrome in the Iranian Population: Waist Circumference, Body Mass Index, or Waist to Hip Ratio?

    PubMed Central

    Gharipour, Mojgan; Sarrafzadegan, Nizal; Sadeghi, Masoumeh; Andalib, Elham; Talaie, Mohammad; Shafie, Davood; Aghababaie, Esmaiel

    2013-01-01

    This study aimed to investigate whether body mass index (BMI), waist circumference (WC), or waist to hip ratio (WHR) could be a better predictor of metabolic syndrome and, if so, what would be the cutoff points for these surrogates to appropriately differentiate metabolic syndrome in different age and sex subgroups. Methods. The present cross-sectional study was conducted on a sample of Isfahan Cohort Study (ICS). In total, 468 individuals (194 with and 274 subjects without metabolic syndrome) according to the National Cholesterol Education Program's Adult Treatment Panel III (ATP-III) criteria were selected. Anthropometric indices were measured and plotted using receiver-operating characteristic (ROC) curves. Results. According to ROC curve analysis, WC and WHR parameters were better indicators of metabolic syndrome compared to BMI in women, whereas in men WHR had a lower discriminating value compared to the other two parameters. Among these three anthropometric parameters, BMI had a lower sensitivity and WC and WHR both had a higher sensitivity for predicting metabolic syndrome in women compared with in men. The cut points for WC were nearly equal in men and women, 90.3 versus 90.0, respectively. Women had higher cut points for BMI (28.5 kg/m2) compared to men (26.0 kg/m2). Our results showed the highest sensitivity and specificity for WC cut points specially in women. To predict metabolic syndrome, we looked into optimal age-specific cut points for BMI, WC, and WHR. The results indicated that WC had the highest discriminating value compared to other indicators in the different age subgroups. The optimal cut points for all three parameters gradually increased with age. Conclusion. Our results demonstrated that regardless of gender and age variables, WC could be a preferred parameter for predicting metabolic syndrome compared to BMI and WHR in Iranian population. PMID:23634297

  4. Galactoglucomannans Increase Cell Population Density and Alter the Protoxylem/Metaxylem Tracheary Element Ratio in Xylogenic Cultures of Zinnia1

    PubMed Central

    Beňová-Kákošová, Anna; Digonnet, Catherine; Goubet, Florence; Ranocha, Philippe; Jauneau, Alain; Pesquet, Edouard; Barbier, Odile; Zhang, Zhinong; Capek, Peter; Dupree, Paul; Lišková, Desana; Goffner, Deborah

    2006-01-01

    Xylogenic cultures of zinnia (Zinnia elegans) provide a unique opportunity to study signaling pathways of tracheary element (TE) differentiation. In vitro TEs differentiate into either protoxylem (PX)-like TEs characterized by annular/helical secondary wall thickening or metaxylem (MX)-like TEs with reticulate/scalariform/pitted thickening. The factors that determine these different cell fates are largely unknown. We show here that supplementing zinnia cultures with exogenous galactoglucomannan oligosaccharides (GGMOs) derived from spruce (Picea abies) xylem had two major effects: an increase in cell population density and a decrease in the ratio of PX to MX TEs. In an attempt to link these two effects, the consequence of the plane of cell division on PX-MX differentiation was assessed. Although GGMOs did not affect the plane of cell division per se, they significantly increased the proportion of longitudinally divided cells differentiating into MX. To test the biological significance of these findings, we have determined the presence of mannan-containing oligosaccharides in zinnia cultures in vitro. Immunoblot assays indicated that β-1,4-mannosyl epitopes accumulate specifically in TE-inductive media. These epitopes were homogeneously distributed within the thickened secondary walls of TEs when the primary cell wall was weakly labeled. Using polysaccharide analysis carbohydrate gel electrophoresis, glucomannans were specifically detected in cell walls of differentiating zinnia cultures. Finally, zinnia macroarrays probed with cDNAs from cells cultured in the presence or absence of GGMOs indicated that significantly more genes were down-regulated rather than up-regulated by GGMOs. This study constitutes a major step in the elucidation of signaling mechanisms of PX- and MX-specific genetic programs in zinnia. PMID:16891547

  5. Evening chronotypes have the increased odds for bronchial asthma and nocturnal asthma.

    PubMed

    Merikanto, Ilona; Englund, Ani; Kronholm, Erkki; Laatikainen, Tiina; Peltonen, Markku; Vartiainen, Erkki; Partonen, Timo

    2014-02-01

    Earlier studies have found associations of chronotypes with a range of health-related factors. In the light of these findings, the behavioral trait of eveningness in particular associates with determinants that might have a negative impact on health. In this study, based on a random sample of population aged 25-74 years living in five large geographical areas in Finland (N = 6089), we tested whether the evening chronotypes have the increased odds for respiratory symptoms and diseases. As a result, after controlling for socio-demographic and lifestyle factors, evening-types had wheezy breathing without respiratory infection, a diagnosed or treated bronchial asthma, awoken in shortness of breath, awoken in heavy to breath, wheezy breathing with dyspnea, wheezy breathing as such and medication for asthma more often than morning-types (odds ratios (ORs) of 1.5-1.9) and intermediate-types (ORs of 1.3-1.6). In addition, evening-types had current medication for asthma, and awoken in coughing more often (OR = 1.5 and OR = 1.4, respectively) than morning-types. Evening-types did not have a diagnosed or treated chronic bronchitis more frequently than others. Our results suggest that the behavioral trait of eveningness associates with the increased odds for the bronchial asthma and nocturnal asthma in particular. PMID:24131153

  6. General parity-odd CMB bispectrum estimation

    SciTech Connect

    Shiraishi, Maresuke; Liguori, Michele; Fergusson, James R. E-mail: michele.liguori@pd.infn.it

    2014-05-01

    We develop a methodology for estimating parity-odd bispectra in the cosmic microwave background (CMB). This is achieved through the extension of the original separable modal methodology to parity-odd bispectrum domains (ℓ{sub 1}+ℓ{sub 2}+ℓ{sub 3} = odd). Through numerical tests of the parity-odd modal decomposition with some theoretical bispectrum templates, we verify that the parity-odd modal methodology can successfully reproduce the CMB bispectrum, without numerical instabilities. We also present simulated non-Gaussian maps produced by modal-decomposed parity-odd bispectra, and show the consistency with the exact results. Our new methodology is applicable to all types of parity-odd temperature and polarization bispectra.

  7. Odds of observing the multiverse

    SciTech Connect

    Dahlen, A.

    2010-03-15

    Eternal inflation predicts that our observable universe lies within a bubble (or pocket universe) embedded in a volume of inflating space. The interior of the bubble undergoes inflation and standard cosmology, while the bubble walls expand outward and collide with other neighboring bubbles. The collisions provide either an opportunity to make a direct observation of the multiverse or, if they produce unacceptable anisotropy, a threat to inflationary theory. The probability of an observer in our bubble detecting the effects of collisions has an absolute upper bound set by the odds of being in the part of our bubble that lies in the forward light cone of a collision; in the case of collisions with bubbles of identical vacua, this bound is given by the bubble nucleation rate times (H{sub O}/H{sub I}){sup 2}, where H{sub O} is the Hubble scale outside the bubbles and H{sub I} is the scale of the second round of inflation that occurs inside our bubble. Similar results were obtained by Freigovel et al. using a different method for the case of collisions with bubbles of much larger cosmological constant; here, it is shown to hold in the case of collisions with identical bubbles as well.

  8. Observed parity-odd CMB temperature bispectrum

    SciTech Connect

    Shiraishi, Maresuke; Liguori, Michele; Fergusson, James R. E-mail: michele.liguori@pd.infn.it

    2015-01-01

    Parity-odd non-Gaussianities create a variety of temperature bispectra in the cosmic microwave background (CMB), defined in the domain: ℓ{sub 1} + ℓ{sub 2} + ℓ{sub 3} = odd. These models are yet unconstrained in the literature, that so far focused exclusively on the more common parity-even scenarios. In this work, we provide the first experimental constraints on parity-odd bispectrum signals in WMAP 9-year temperature data, using a separable modal parity-odd estimator. Comparing theoretical bispectrum templates to the observed bispectrum, we place constraints on the so-called nonlineality parameters of parity-odd tensor non-Gaussianities predicted by several Early Universe models. Our technique also generates a model-independent, smoothed reconstruction of the bispectrum of the data for parity-odd configurations.

  9. Changes of Microbial Population in the Rumen of Dairy Steers as Influenced by Plant Containing Tannins and Saponins and Roughage to Concentrate Ratio

    PubMed Central

    Anantasook, N.; Wanapat, M.; Cherdthong, A.; Gunun, P.

    2013-01-01

    The objective of this study was to investigate microbial population in the rumen of dairy steers as influenced by supplementing with dietary condensed tannins and saponins and different roughage to concentrate ratios. Four, rumen fistulated dairy steers (Bos indicus) were used in a 2×2 factorial arrangement in a 4×4 Latin square design. The main factors were two roughage to concentrate ratios (R:C, 60:40 and 40:60) and two supplementations of rain tree pod meal (RPM) (0 and 60 g/kg of total DM intake). Chopped 30 g/kg urea treated rice straw was used as a roughage source. All animals received feed according to respective R:C ratios at 25 g/kg body weight. The RPM contained crude tannins and saponins at 84 and 143 g/kg of DM, respectively. It was found that ruminal pH decreased while ruminal temperature increased by a higher concentrate ratio (R:C 40:60) (p<0.05). In contrast, total bacterial, Ruminococus albus and viable proteolytic bacteria were not affected by dietary supplementation. Numbers of fungi, cellulolytic bacteria, Fibrobactor succinogenes and Ruminococus flavefaciens were higher while amylolytic bacteria was lower when steers were fed at 400 g/kg of concentrate. The population of Fibrobactor succinogenes, was found to be higher with RPM supplementation. In addition, the use of real-time PCR technique indicated that the population of protozoa and methanogens were decreased (p<0.05) with supplementation of RPM and with an increasing concentrate ratio. Supplementation of RPM and feeding different concentrate ratios resulted in changing the rumen microbes especially, when the animals were fed at 600 g/kg of concentrate and supplemented with RPM which significantly reduced the protozoa and methanogens population. PMID:25049745

  10. Is otolith microchemistry (Sr: Ca and Ba:Ca ratios) useful to identify Mugil curema populations in the southeastern Caribbean Sea?

    PubMed

    Avigliano, E; Callicó-Fortunato, R; Buitrago, J; Volpedo, A V

    2015-11-01

    The aim of the present study was to evaluate the potential use of otolith microchemistry (Sr:Ca and Ba:Ca ratios) to identify silver mullet, Mugil curema, populations in Southeastern Caribbean Sea. Fish samples were collected in 7 areas of Nueva Esparta State (Venezuela). The otolith Sr:Ca and Ba:Ca ratios and water Sr:Ca were determined (by ICP-OES and EDTA volumetric method). Otoliths Sr:Ca and Ba:Ca ratios and Sr:Ca partition coefficient of mullets in Cubagua island (south of the State) were significantly different from ratios in La Guardia (north of the State). A discriminant analysis of otolith Sr:Ca and Ba:Ca ratios separated Cubagua Island from La Guardia values. These results suggest the existence of different mullet groups in the Southeastern Caribbean Sea. For this, the simultaneous use of Sr:Ca and Ba:Ca ratios could be a potential tool to identify populations in the study area. PMID:26628220

  11. BOOK REVIEW: The Odd Quantum

    NASA Astrophysics Data System (ADS)

    Reynolds, Helen

    2000-03-01

    The Odd Quantum is aiming to be odd. Falling between being a quantum mechanics textbook and a `popular' science book, it aims to convey something of the substance of quantum mechanics without being overly technical or professional. It does not shy away from the mathematics of the subject or resort solely to analogy and metaphor, as so often is the case. Books aimed at the lay reader tend to take on a particular aspect of quantum mechanics, for example, wave-particle duality, and can do little more than hint at the complexity of the subject. This book is more than a textbook on quantum mechanics; it gives the reader a comprehensive account of history and an appreciation of the nature of quantum mechanics. The introductory chapters deal with the earlier part of the century and the thinking of that time. The approach is familiar, as are the stories that Treiman tells, but he also manages to convey the speed with which ideas changed and the excitement this brought to the physics community. Classical ideas of force and energy are dealt with succinctly but with sufficient depth to set up the reader for what is to come; Maxwell's equations and a brief glimpse at relativity are included. This is followed by a brief description of what the author terms the `old' quantum mechanics, in effect a highly readable tour around black body radiation and spectroscopy and the models of the atom that emerged from them. The `new' quantum mechanics begins about a third of the way through the book, and in a chapter entitled `Foundations' starts gently but rapidly moves into a detailed mathematical treatment. This section, of necessity, relapses into the style of a textbook and covers a lot of ground quickly. It is at this point that the non-specialist popular science readers for whom Treiman has written this book may become a little bemused. Concepts such as non-degeneracy and operators come thick and fast. It is difficult to imagine an educated non-physicist with little mathematical

  12. Neutron-proton multiplets in the odd-odd nucleus 53 37 90Rb

    NASA Astrophysics Data System (ADS)

    Czerwiński, M.; RzÄ ca-Urban, T.; Urban, W.; BÄ czyk, P.; Sieja, K.; Timár, J.; Nyakó, B. M.; Kuti, I.; Tornyi, T. G.; Atanasova, L.; Blanc, A.; Jentschel, M.; Mutti, P.; Köster, U.; Soldner, T.; de France, G.; Simpson, G. S.; Ur, C. A.

    2016-03-01

    Medium-spin excited levels in 90Rb, populated in the fission of 235U induced by neutrons, have been observed for the first time. γ radiation from fission has been measured by using the EXILL array of Ge detectors at the cold-neutron-beam facility PF1B of the Institut Laue-Langevin, Grenoble. Low-energy levels are interpreted as members of the π p3/2 -1ν (d5/2) 3 , π f5/2 -1ν (d5/2) 3 , and π g9 /2ν (d5/2) 3 multiplets with the 0- ground state due to the seniority-3 coupling in the ν d5 /2 shell. Analogous anomalous coupling within the π g9 /2ν (d5/2) 3 configuration explains the 5+, 6+, and 7+ triplet of states, observed at medium spins, similar to the triplet seen in the N =53 isotone, 88Br. Shell-model calculations reproduce well the proposed structures in Rb,9088 and support the seniority-3 coupling in N =53 isotones and its absence in N =51 isotones. The structure of the odd-odd 88Rb and 90Rb nuclei provides an argument in favor of the collectivity building up at the neutron number N =53 .

  13. Positronium Decay and C-Odd Bosons

    NASA Astrophysics Data System (ADS)

    Skalsey, M.; Conti, R. S.

    1996-05-01

    Triplet-state orthopositronium (o-Ps) decay rate measurements are in marked disagreement by 0.17% with QED theoretical calculations done up to, but not including order α ^2 radiative and relativistic corrections. The existence of a rare exotic decay branch o-Ps arrow 2γ + X^0 (where X^0 is a neutral, massive C-odd boson) could resolve the discrepancy. We have searched for, but have not found evidence of the X^0 in two recent experiments.(M. Skalsey and R.S. Conti, Phys. Rev. D51), 6292 (1995) and submitted to Phys. Rev. Lett. Stringent limits are placed on the exotic decay branching ratio e^+ +e^- arrow X^0 +γ as a function of the X^0 mass and lifetime. The results are interpreted for two distinct models of X^0 interactions and related to o-Ps decay as well as other experiments, including singlet-state parapositronium decay rate measurements. *Supported by NSF grant PHY-9417854 and the University of Michigan.

  14. The Competition Between Collective and Single - Effects in the Odd-Odd Nuclei LANTHANUM-128,130.

    NASA Astrophysics Data System (ADS)

    Godfrey, Mark Jonathan

    Available from UMI in association with The British Library. Excited states in the odd-odd nuclei ^{128,130}La have been investigated to high-spin using gamma-ray spectroscopy. The nucleus ^{128}La was identified using the Daresbury Recoil Separator, and gamma -gamma coincidence data were taken on both nuclei with the TESSA3 array. Angular distributions were also measured for ^{128} La. Seven distinct bands have been observed, three in ^{128}La and four in ^{130}La, with four of these structures being seen for the first time. Two of the bands in each nucleus correspond to near-prolate nuclear shapes, one based on a pih _{11/2} otimes nuh _{11/2} structure and the other on a pih_{11/2 } otimes nug_{7/2 } configuration. A further band in each nucleus has similar properties to what would be expected for a collective oblate structure. In addition the first odd -proton system superdeformed band has been found in ^{130}La. The experimental evidence for these structures will be discussed in terms of the variation in energy level signature splitting, B(M1)/B(E2) ratios and mixing ratios as a function of rotational frequency and single particle configuration. The nature of the particles responsible for backbends in the near-prolate bands will be conclusively proved. The results will be interpreted in terms of the cranked shell model, an odd-odd particle-rotor model and deformation self-consistent cranking calculations. They will be compared to other odd and odd-odd systems in the A = 130 region. Long-range p-n and n-n interactions are investigated through the measurement of residual interactions. Theoretical interactions are obtained from deformation self-consistent cranking calculations, which contain no long-range interactions, to estimate the nuclear mean field. The results are discussed in terms of the variation in the spatial overlap of the various wavefunctions and changes in the mean field, as a function of particle number, configuration and rotational frequency.

  15. Improving the Odds of Surviving Sepsis

    MedlinePlus

    ... Improving the Odds of Surviving Sepsis Inside Life Science View All Articles | Inside Life Science Home Page Improving the Odds of Surviving Sepsis ... Threatening Bacterial Infection Remains Mysterious This Inside Life Science article also appears on LiveScience . Learn about related ...

  16. The nuclear structure of deformed odd-odd nuclei: Experimental and theoretical investigations

    SciTech Connect

    Hoff, R.W.; Jain, A.K.; Sood, P.C.; Sheline, R.K.

    1988-06-06

    Previous surveys of experimental level structure in deformed odd-odd nuclei have been updated with recent results for the lanthanide and actinide regions. The relative strengths of the effective neutron-proton interaction derived from these data are compared. The predictive power of a semi-empirical model for level structure in deformed odd-odd nuclei is demonstrated. Comparison is made with recent Hartree-Fock calculations of selected nuclei.

  17. Social Adjustment among Taiwanese Children with Symptoms of ADHD, ODD, and ADHD Comorbid with ODD

    ERIC Educational Resources Information Center

    Tseng, Wan-Ling; Kawabata, Yoshito; Gau, Susan Shur-Fen

    2011-01-01

    This study examined social problems at school and relationships with peers, siblings, mothers, and fathers among children with ADHD only (n = 41), ODD only (n = 14), ADHD + ODD (n = 47), and normal controls (n = 204) from a school-based sample of 2,463 first to ninth graders in Taiwan. ADHD and ODD symptoms were determined by teacher and mother…

  18. Unexpected consequences of a drier world: evidence that delay in late summer rains biases the population sex ratio of an insect.

    PubMed

    Bonal, Raul; Hernández, Marisa; Espelta, Josep M; Muñoz, Alberto; Aparicio, José M

    2015-09-01

    The complexity of animal life histories makes it difficult to predict the consequences of climate change on their populations. In this paper, we show, for the first time, that longer summer drought episodes, such as those predicted for the dry Mediterranean region under climate change, may bias insect population sex ratio. Many Mediterranean organisms, like the weevil Curculio elephas, become active again after summer drought. This insect depends on late summer rainfall to soften the soil and allow adult emergence from their underground refuges. We found that, as in many protandric species, more C. elephas females emerged later in the season. Male emergence timing was on average earlier and also more dependent on the beginning of late summer rainfall. When these rains were delayed, the observed weevil sex ratio was biased towards females. So far, the effects of global warming on animal sex ratios has been reported for temperature-dependent sex determination in reptiles. Our results show that rainfall timing can also bias the sex ratio in an insect, and highlight the need for keeping a phenological perspective to predict the consequences of climate change. We must consider not just the magnitude of the predicted changes in temperature and rainfall but also the effects of their timing. PMID:26473046

  19. RAD SNP markers as a tool for conservation of dolphinfish Coryphaena hippurus in the Mediterranean Sea: Identification of subtle genetic structure and assessment of populations sex-ratios.

    PubMed

    Maroso, Francesco; Franch, Rafaella; Dalla Rovere, Giulia; Arculeo, Marco; Bargelloni, Luca

    2016-08-01

    Dolphinfish is an important fish species for both commercial and sport fishing, but so far limited information is available on genetic variability and pattern of differentiation of dolphinfish populations in the Mediterranean basin. Recently developed techniques allow genome-wide identification of genetic markers for better understanding of population structure in species with limited genome information. Using restriction-site associated DNA analysis we successfully genotyped 140 individuals of dolphinfish from eight locations in the Mediterranean Sea at 3324 SNP loci. We identified 311 sex-related loci that were used to assess sex-ratio in dolphinfish populations. In addition, we identified a weak signature of genetic differentiation of the population closer to Gibraltar Strait in comparison to other Mediterranean populations, which might be related to introgression of individuals from Atlantic. No further genetic differentiation could be detected in the other populations sampled, as expected considering the known highly mobility of the species. The results obtained improve our knowledge of the species and can help managing dolphinfish stock in the future. PMID:27450636

  20. Persistent sex-by-environment effects on offspring fitness and sex-ratio adjustment in a wild bird population.

    PubMed

    Bowers, E Keith; Thompson, Charles F; Sakaluk, Scott K

    2015-03-01

    A major component of sex-allocation theory, the Trivers-Willard model (TWM), posits that sons and daughters are differentially affected by variation in the rearing environment. In many species, the amount of parental care received is expected to have differing effects on the fitness of males and females. When this occurs, the TWM predicts that selection should favour adjustment of the offspring sex ratio in relation to the expected fitness return from offspring. However, evidence for sex-by-environment effects is mixed, and little is known about the adaptive significance of producing either sex. Here, we test whether offspring sex ratios vary according to predictions of the TWM in the house wren (Troglodytes aedon, Vieillot). We also test the assumption of a sex-by-environment effect on offspring using two experiments, one in which we manipulated age differences among nestlings within broods, and another in which we held nestling age constant but manipulated brood size. As predicted, females with high investment ability overproduced sons relative to those with lower ability. Males were also overproduced early within breeding seasons. In our experiments, the body mass of sons was more strongly affected by the sibling-competitive environment and resource availability than that of daughters: males grew heavier than females when reared in good conditions but were lighter than females when in poor conditions. Parents rearing broods with 1:1 sex ratios were more productive than parents rearing broods biased more strongly towards sons or daughters, suggesting that selection favours the production of mixed-sex broods. However, differences in the condition of offspring as neonates persisted to adulthood, and their reproductive success as adults varied with the body mass of sons, but not daughters, prior to independence from parental care. Thus, selection should favour slight but predictable variations in the sex ratio in relation to the quality of offspring that parents are

  1. Persistent sex-by-environment effects on offspring fitness and sex-ratio adjustment in a wild bird population

    PubMed Central

    Bowers, E. Keith; Thompson, Charles F.; Sakaluk, Scott K.

    2014-01-01

    Summary A major component of sex-allocation theory, the Trivers-Willard Model (TWM), posits that sons and daughters are differentially affected by variation in the rearing environment. In many species, the amount of parental care received is expected to have differing effects on the fitness of males and females. When this occurs, the TWM predicts that selection should favour adjustment of the offspring sex ratio in relation to the expected fitness return from offspring. However, evidence for sex-by-environment effects is mixed and little is known about the adaptive significance of producing either sex. Here, we test whether offspring sex ratios vary according to predictions of the TWM in the house wren (Troglodytes aedon, Vieillot). We also test the assumption of a sex-by-environment effect on offspring using two experiments, one in which we manipulated age-differences among nestlings within broods, and another in which we held nestling age constant but manipulated brood size. As predicted, females with high investment ability over-produced sons relative to those with lower ability. Males were also over-produced early within breeding seasons. In our experiments, the body mass of sons was more strongly affected by the sibling-competitive environment and resource availability than that of daughters: males grew heavier than females when reared in good conditions but were lighter than females when in poor conditions. Parents rearing broods with 1:1 sex ratios were more productive than parents rearing broods biased more strongly towards sons or daughters, suggesting that selection favours the production of mixed-sex broods. However, differences in the condition of offspring as neonates persisted to adulthood, and their reproductive success as adults varied with the body mass of sons, but not daughters, prior to independence from parental care. Thus, selection should favour slight but predictable variations in the sex ratio in relation to the quality of offspring that

  2. Variations in male-female infant ratios among births to Canadian- and Indian-born mothers, 1990-2011: a population-based register study

    PubMed Central

    Urquia, Marcelo L.; Ray, Joel G.; Wanigaratne, Susitha; Moineddin, Rahim; O'Campo, Patricia J.

    2016-01-01

    Background: We assessed variations in the male-female infant ratios among births to Canadian-born and Indian-born mothers according to year of birth, province and country of birth of each parent. Methods: In this population-based register study, we analyzed birth certificates of 5 853 970 singleton live births to Canadian-born and 177 990 singleton live births to Indian-born mothers giving birth in Canada from 1990 to 2011. Male-female ratios were stratified by live birth order and plotted by year of birth. Logistic regression was used to assess whether ratios varied between Canadian provinces and according to the birthplace of each parent. The deficit in the number of girls was estimated using bootstrap methods. Results: Among Canadian-born mothers, male-female ratios were about 1.05, with negligible fluctuations by birth order, year and province. Among Indian-born mothers, the overall male-female ratio at the third birth was 1.38 (95% confidence interval [CI] 1.34-1.41) and was 1.66 (95% CI 1.56-1.76) at the fourth or higher-order births. There was little variability in the ratios between provinces. Couples involving at least 1 Indian-born parent had higher than expected male-female ratios at the second and higher-order births, particularly when the father was Indian-born. The deficit in the expected number of girls among Indian immigrants to Canada in the study period was estimated to be 4472 (95% CI 3211-5921). Interpretation: Fewer than expected girls at the third and higher-order births have been born to Indian immigrants across Canada since 1990. This trend was also seen among couples of mixed nativity, including those involving a Canadian-born mother and an Indian-born father. Fathers should be considered when investigating sex ratios at birth. PMID:27398354

  3. First Evidence for the Existence of Odd Toroidal Alfven Eigenmodes (TAEs) from the Simultaneous Observation of Even and Odd TAEs on the Joint European Torus

    SciTech Connect

    G.J. Kramer; S.E. Sharapov; R. Nazikian; N.N. Gorelenkov; R. Budny; JET-EFDA contributors

    2003-01-15

    Experimental evidence is presented for the existence of the theoretically predicted odd Torodicity-induced Alfven Eigenmode (TAEs) from the simultaneous appearance of odd and even TAEs in a normal shear discharge. The modes are observed in low central magnetic shear plasmas created by injecting lower hybrid current drive. A fast ion population was created by applying ion cyclotron heating at the high field side to excite the TAEs in the weak magnetic shear region. The odd TAEs were identified from their frequency, mode number, and timing relative to the even TAEs.

  4. Alignments, additivity, and signature inversion in odd-odd {sup 170}Ta : a comprehensive high-spin study.

    SciTech Connect

    Aguilar, A.; Hartley, D. J.; Riley, M. A.; Teal, C.; Carpenter, M. P.; Chowdhury, P.; Danchev, M.; Djongolov, M. K.; Hagemann, G. B.; Hecht, A. A.; Janssens, R. V. F.; Kondev, F. G.; Lauritsen, T.; Ma, W. C.; Mohr, W. H.; Moore, E. F.; Odegard, S. W.; Riedinger, L. L.; Sletten, G.; Tandel, S. K.; Vanhoy, J. R.; Wang, X.; Zhu, S.; Florida State Univ.; U.S. Naval Academy; Univ. of Massachusetts; Univ. of Tennessee; Niels Bohr Inst.; Mississippi State Univ.; Univ. of Oslo

    2010-01-01

    High-spin states (I?50?) of the odd-odd nucleus 170Ta have been investigated with the 124Sn(51V,5n) reaction. The resolving power of Gammasphere has allowed for the observation of eleven rotational bands (eight of which are new) and over 430 transitions ( 350 of which are new) in this nucleus. Many interband transitions have been observed such that the relative spins and excitation energies of the 11 bands have been established. This is an unusual circumstance in an odd-odd study. Configurations have been assigned to most of these bands based upon features such as alignment properties, band crossings, B(M1)/B(E2) ratios, and the additivity of Routhians. A systematic study of the frequency at which normal signature ordering occurs in the ?h9/2?i13/2 band has been performed and it is found that its trend is opposite to that observed in the ?h11/2?i13/2 bands. A possible interpretation of these trends is discussed based on a proton-neutron interaction.

  5. Predicting Intrinsic mid-IR to optical flux ratios for galaxies of different types using Spectral Synthesis Models of Composite Stellar Populations

    NASA Astrophysics Data System (ADS)

    Kim, Duho; Jansen, Rolf A.; Windhorst, Rogier A.

    2016-01-01

    We analyze the intrinsic flux ratios of simple and composite stellar populations for various visible--near-infrared filters with respect to ˜3.5μm (L-band), and their dependence on metallicity, star-formation history, and effective mean age. This study is motivated by the fact that light from galaxies is reddened and attenuated by dust via scattering and absorption, where different sightlines across the face of a galaxy suffer various amounts of extinction. Ignoring the effects of this extinction could lead one to infer lower stellar mass, and SFR, or higher metallicity. Tamura et al. (2009) developed an approximate method, dubbed the "βV" method, which corrects for dust-extinction on a pixel-by-pixel basis, by comparing the observed flux ratio and empirical estimate of the intrinsic flux ratio of optical and ˜3.5μm broadband data. Here, we aim to validate and test the limits of the βV method for various filters spanning the visible through near-infrared wavelength range. Through extensive modeling, we test their assumptions for the intrinsic flux ratios for a wide variety of simple and composite stellar populations. We build spectral energy distributions (SEDs) of simple stellar populations (SSPs), by adopting Starburst99 and BC03 models for young (<9Myr) and old (>100Myr) stellar populations, respectively, and linear combinations of these for intermediate ages. We then construct composite stellar population (CSP) SEDs by combining SSP SEDs for various realistic star-formation histories (SFHs). We convolve filter response curves of visible--near-infrared filters for HST imaging surveys and mid-infrared filters in current (WISE, Spitzer/IRAC) and near-future use (JWST/NIRCam) with each model SED, to obtain intrinsic flux ratios (βλ,0). We find that βNIR,0 is only varying slightly as a function of metallicity but is insensitive to SFH or redshift (z≤2). We also find a narrow range of βV,0 (0.7+0.05-0.08) for early Hubble type galaxies (E and S0) using

  6. Topology Explains Why Automobile Sunshades Fold Oddly

    ERIC Educational Resources Information Center

    Feist, Curtis; Naimi, Ramin

    2009-01-01

    Automobile sunshades always fold into an "odd" number of loops. The explanation why involves elementary topology (braid theory and linking number, both explained in detail here with definitions and examples), and an elementary fact from algebra about symmetric group.

  7. Population.

    ERIC Educational Resources Information Center

    King, Pat; Landahl, John

    This pamphlet has been prepared in response to a new problem, a rapidly increasing population, and a new need, population education. It is designed to help teachers provide their students with some basic population concepts with stress placed on the elements of decision making. In the first section of the pamphlet, some of the basic concepts of…

  8. PCNA appears in two populations of slow and fast diffusion with a constant ratio throughout S-phase in replicating mammalian cells

    PubMed Central

    Zessin, Patrick J. M.; Sporbert, Anje; Heilemann, Mike

    2016-01-01

    DNA replication is a fundamental cellular process that precedes cell division. Proliferating cell nuclear antigen (PCNA) is a central scaffold protein that orchestrates DNA replication by recruiting many factors essential for the replication machinery. We studied the mobility of PCNA in live mammalian cells using single-particle tracking in combination with photoactivated-localization microscopy (sptPALM) and found two populations. The first population which is only present in cells with active DNA replication, showed slow diffusion and was found to be located in replication foci. The second population showed fast diffusion, and represents the nucleoplasmic pool of unbound PCNA not involved in DNA replication. The ratio of these two populations remained constant throughout different stages of S-phase. A fraction of molecules in both populations showed spatially constrained mobility. We determined an exploration radius of ~100 nm for 13% of the slow-diffusing PCNA molecules, and of ~600 nm for 46% of the fast-diffusing PCNA molecules. PMID:26758689

  9. Being WISE. I. Validating stellar population models and M {sub *}/L ratios at 3.4 and 4.6 μm

    SciTech Connect

    Norris, Mark A.; Meidt, Sharon; Van de Ven, Glenn; Schinnerer, Eva; Groves, Brent; Querejeta, Miguel

    2014-12-10

    Using data from the Wide-field Infrared Survey Explorer mission, we have measured near infra-red (NIR) photometry of a diverse sample of dust-free stellar systems (globular clusters, dwarf and giant early-type galaxies) which have metallicities that span the range -2.2 < [Fe/H] (dex) < 0.3. This dramatically increases the sample size and broadens the metallicity regime over which the 3.4 (W1) and 4.6 μm (W2) photometry of stellar populations have been examined. We find that the W1 – W2 colors of intermediate and old (>2 Gyr) stellar populations are insensitive to the age of the stellar population, but that the W1 – W2 colors become bluer with increasing metallicity, a trend not well reproduced by most stellar population synthesis (SPS) models. In common with previous studies, we attribute this behavior to the increasing strength of the CO absorption feature located in the 4.6 μm bandpass with metallicity. Having used our sample to validate the efficacy of some of the SPS models, we use these models to derive stellar mass-to-light ratios in the W1 and W2 bands. Utilizing observational data from the SAURON and ATLAS3D surveys, we demonstrate that these bands provide extremely simple, yet robust stellar mass tracers for dust free older stellar populations that are freed from many of the uncertainties common among optical estimators.

  10. Marriage season, promptness of successful pregnancy and first-born sex ratio in a historical natural fertility population - evidence for sex-dependent early pregnancy loss?

    NASA Astrophysics Data System (ADS)

    Nonaka, K.; Desjardins, Bertrand; Charbonneau, Hubert; Légaré, Jacques; Miura, Teiji

    We investigated population-based vital records of the seventeenth and eighteenth century French Canadian population to assess the effects of marriage season on the outcome of the first births under natural fertility conditions (n=21,698 marriages). Promptness of the first successful conception after marriage differed according to marriage season; the proportion of marriages with a marriage-first birth interval of 8.0-10.0 months was lowest (34%) for marriages in August-October (P=0.001). Although the male/female sex ratio of the babies born with an interval of 8.0-10.0 months was generally higher (1.10) than those with an interval of 10.0-24.0 months (1.05), the marriages in August-October resulted in a significantly reduced sex ratio (0.96) among only the prompt conceptions (P=0.026). We discuss whether this seasonal reduction of the sex ratio could be partly explained by a clustered pregnancy loss of male zygotes in early pregnancy.

  11. Dietary and physiological controls on the hydrogen and oxygen isotope ratios of hair from mid-20th century indigenous populations.

    PubMed

    Bowen, Gabriel J; Ehleringer, James R; Chesson, Lesley A; Thompson, Alexandra H; Podlesak, David W; Cerling, Thure E

    2009-08-01

    A semimechanistic model has recently been proposed to explain observed correlations between the H and O isotopic composition of hair from modern residents of the USA and the isotopic composition of drinking water, but the applicability of this model to hair from non-USA and preglobalization populations is unknown. Here we test the model against data from hair samples collected during the 1930s-1950s from populations of five continents. Although C and N isotopes confirm that the samples represent a much larger range of dietary "space" than the modern USA residents, the model is able to reproduce the observed delta(2)H and delta(18)O values given reasonable adjustments to 2 model parameters: the fraction of dietary intake derived from locally produced foods and the fraction of keratin H fixed during the in vivo synthesis of amino acids. The model is most sensitive to the local dietary intake, which appears to constitute between 60% and 80% of diet among the groups sampled. The isotopic data are consistent with a trophic-level effect on protein H isotopes, which we suggest primarily reflects mixing of (2)H-enriched water and (2)H-depleted food H in the body rather than fractionation during biosynthesis. Samples from Inuit groups suggest that humans with marine-dominated diets can be identified on the basis of coupled delta(2)H and delta(18)O values of hair. These results indicate a dual role for H and O isotopic measurements of keratin, including both biological (diet, physiology) and environmental (geographic movement, paleoclimate) reconstruction. PMID:19235792

  12. Seasonal Variation in Female Mate Choice and Operational Sex Ratio in Wild Populations of an Annual Fish, Austrolebias reicherti

    PubMed Central

    Passos, Carlos; Tassino, Bettina; Reyes, Federico; Rosenthal, Gil G.

    2014-01-01

    The intensity of mating competition and the potential benefits for female of mating with certain males can be influenced by several extrinsic factors, such that behavioral decisions can be highly context-dependent. Short-lived species with a single reproductive season are a unique model to study context-sensitive mating decisions. Through exhaustive sampling in the field and simultaneous choice tests in the laboratory, we evaluated operational sex ratio (OSR) and female mate choice at the beginning and end of the reproductive season in the annual killifish Austrolebias reicherti. We found seasonal change in both OSR and female mate choice. At the start of the reproductive season the OSR did not deviate from parity, and females preferred larger males. Later in the reproductive season, while the proportion of males in the ponds decreased, females became unselective with respect to male size. The particular biological cycle of annual killifish, where both life expectancy and mating opportunities decline sharply over a short timescale, could account for the seasonal change in female choice. Reduction in choosiness could arise from diminished reproductive prospects due to a decline in male availability. Moreover, as the end of the season approaches, any benefits of choosiness are presumably reduced: a female’s fitness will be higher if she mates with any male than if she forgoes reproduction and dies. Future work will disentangle the mechanisms underlying seasonal changes in mating preferences, notably direct responses to demographic factors, environmental cues, or intrinsic changes during development. PMID:25029019

  13. Even-odd staggering of the spectroscopic factor as new evidence for α clustering

    NASA Astrophysics Data System (ADS)

    Delion, D. S.; Dumitrescu, A.; Baran, V. V.

    2016-04-01

    We evidence a staggering effect of the experimental spectroscopic factors corresponding to even-even and odd-mass (odd-mass and odd-odd) α emitters. The comparison to the theoretical estimate within the standard Bardeen-Cooper-Schrieffer (BCS) approach reveals a similar staggering, but with a different behavior. It turns out that the ratio between corresponding experimental and theoretical spectroscopic factors is proportional to the experimental reduced decay width. A similar dependence was found in a previous work between the strength of the quadrupole-quadrupole α -core interaction, describing the α -decay fine structure and the reduced width. Thus, the even-odd staggering effect in the spectroscopic factor is a new evidence of the α -clustering phenomenon in medium and heavy nuclei.

  14. Performance of the waist-to-height ratio in identifying obesity and predicting non-communicable diseases in the elderly population: A systematic literature review.

    PubMed

    Corrêa, Márcia Mara; Thumé, Elaine; De Oliveira, Elizabete Regina Araújo; Tomasi, Elaine

    2016-01-01

    A systematic review was carried out aiming to collect evidence on the use of the waist-to-height ratio (WHtR) on the elderly population, focusing on validity measures to identify the best anthropometric indicator in assessing obesity associated with non-communicable diseases. The review consisted in a search of papers published on the databases Pubmed, Web of Science, and Lilacs, with no restriction regarding period of publication, using the following combinations: abdominal fat or overweight or obesity and waist-to-height ratio or waist height or waist ht or WHtR or waist to stature ratio or wst stature or WSR or stature and girth. Sixteen papers were selected, most of which with high methodological quality. The receiver-operating characteristic (ROC) curves was the validity measure explored in 13 papers, followed by sensitivity and specificity measures. In all studies, the body mass index (BMI) and waist circumference (WC) received special attention for analysis along with WHtR. Five manuscripts showed evidence of WHtR being the best anthropometric index when used alone, four showed that both WHtR and WC had the best discriminatory power in predicting cardiovascular risk factors compared to the other indices, and two ranked WHtR at the same performance level as waist-to-hip ratio (WHR) and BMI. An association was shown of the obesity assessed by WHtR in predicting risk factors for cardiovascular diseases, metabolic syndrome, and diabetes compared to other anthropometric parameters. PMID:27061665

  15. Illness representation on H1N1 influenza and preventive behaviors in the Hong Kong general population.

    PubMed

    Mo, Phoenix K H; Lau, Joseph T F

    2015-12-01

    This study examined illness representations of new influenza Human Swine Influenza A (H1N1) and association with H1N1 preventive behaviors among 300 Chinese adults using a population-based randomized telephone survey. Results showed that relatively few participants thought H1N1 would have serious consequences (12%-15.7%) and few showed negative emotional responses toward H1N1 (9%-24.7%). The majority of the participants thought H1N1 could be controlled by treatment (70.4%-72.7%). Multiple logistic regression analyses showed that treatment control (odds ratio = 1.78) and psychological attribution (odds ratio = .75) were associated with intention to take up influenza vaccination. Emotional representations were associated with lower likelihood of wearing face mask (odds ratio = .77) and hand washing (odds ratio = .67). Results confirm that illness representation variables are associated with H1N1 preventive behaviors. PMID:24423574

  16. Odd-frequency Superconductivity in Driven Systems

    NASA Astrophysics Data System (ADS)

    Triola, Christopher; Balatsky, Alexander

    We show that Berezinskii's classification of the symmetries of Cooper pair amplitudes in terms of parity under transformations that invert spin, space, time, and orbital degrees of freedom holds for driven systems even in the absence of translation invariance. We then discuss the conditions under which pair amplitudes which are odd in frequency can emerge in driven systems. Considering a model Hamiltonian for a superconductor coupled to an external driving potential, we investigate the influence of the drive on the anomalous Green's function, density of states, and spectral function. We find that the anomalous Green's function develops odd in frequency component in the presence of an external drive. Furthermore we investigate how these odd-frequency terms are related to satellite features in the density of states and spectral function. Supported by US DOE BES E 304.

  17. Tilted excitation implies odd periodic resonances.

    PubMed

    Depetri, G I; Sartorelli, J C; Marin, B; Baptista, M S

    2016-07-01

    Our aim is to unveil how resonances of parametric systems are affected when symmetry is broken. We showed numerically and experimentally that odd resonances indeed come about when the pendulum is excited along a tilted direction. Applying the Melnikov subharmonic function, we not only determined analytically the loci of saddle-node bifurcations delimiting resonance regions in parameter space but also explained these observations by demonstrating that, under the Melnikov method point of view, odd resonances arise due to an extra torque that appears in the asymmetric case. PMID:27575118

  18. Tilted excitation implies odd periodic resonances

    NASA Astrophysics Data System (ADS)

    Depetri, G. I.; Sartorelli, J. C.; Marin, B.; Baptista, M. S.

    2016-07-01

    Our aim is to unveil how resonances of parametric systems are affected when symmetry is broken. We showed numerically and experimentally that odd resonances indeed come about when the pendulum is excited along a tilted direction. Applying the Melnikov subharmonic function, we not only determined analytically the loci of saddle-node bifurcations delimiting resonance regions in parameter space but also explained these observations by demonstrating that, under the Melnikov method point of view, odd resonances arise due to an extra torque that appears in the asymmetric case.

  19. Experimental level-structure determination in odd-odd actinide nuclei

    SciTech Connect

    Hoff, R.W.

    1985-04-04

    The status of experimental determination of level structure in odd-odd actinide nuclei is reviewed. A technique for modeling quasiparticle excitation energies and rotational parameters in odd-odd deformed nuclei is applied to actinide species where new experimental data have been obtained by use of neutron-capture gamma-ray spectroscopy. The input parameters required for the calculation are derived from empirical data on single-particle excitations in neighboring odd-mass nuclei. Calculated configuration-specific values for the Gallagher-Moszkowski splittings are used. Calculated and experimental level structures for /sup 238/Np, /sup 244/Am, and /sup 250/Bk are compared, as well as those for several nuclei in the rare-earth region. The agreement for the actinide species is excellent, with bandhead energies deviating 22 keV and rotational parameters 5%, on the average. Applications of this modeling technique are discussed.

  20. Babesia divergens builds a complex population structure composed of specific ratios of infected cells to ensure a prompt response to changing environmental conditions.

    PubMed

    Cursino-Santos, Jeny R; Singh, Manpreet; Pham, Petra; Rodriguez, Marilis; Lobo, Cheryl A

    2016-06-01

    Babesia parasites cause a malaria-like febrile illness by infection of red blood cells (RBCs). Despite the growing importance of this tick-borne infection, its basic biology has been neglected. Using novel synchronization tools, the sequence of intra-erythrocytic events was followed from invasion through development and differentiation to egress. The dynamics of the parasite population were studied in culture, revealing for the first time, the complete array of morphological forms in a precursor-product relationship. Important chronological constants including Babesia's highly unusual variable intra-erythrocytic life cycle, the life span of each population of infected cells and the time required for the genesis of the different parasite stages were elucidated. Importantly, the maintenance of specific ratios of the infected RBC populations was shown to be responsible for the parasites' choice of developmental pathways, enabling swift responses to changing environmental conditions like availability of RBCs and nutrition. These results could impact the control of parasite proliferation and therefore disease. PMID:26663747

  1. Odd-Man-Out and Intelligence.

    ERIC Educational Resources Information Center

    Diascro, Matthew N.; Brody, Nathan

    1994-01-01

    The relationship between odd-man-out reaction time tasks and intelligence was examined in 2 experiments involving 79 college students. The two experiments indicate that tasks that assess the ability to perceive relationships among stimuli rapidly are good measures of general intelligence. (SLD)

  2. The Alleged Oddness of Ethical Egoism

    ERIC Educational Resources Information Center

    Marietta, Don E., Jr.

    1977-01-01

    There are some critics of ethical egoism who treat it seriously as an ethical doctrine, but consider it an odd approach. Examines this doctrine and suggests that if we are to have the benefit of egoism as a sound ethical approach, or rightly assess its inadequacies, we must first see it fairly. (Author/RK)

  3. Odd numbers of photons and teleportation

    SciTech Connect

    Enk, S.J. van

    2003-02-01

    Several teleportation protocols, namely those using entangled coherent states, entangled squeezed states, and the single-photon Einstein-Podolsky-Rosen state, are all shown to be particular instances of a more general scheme that relies on the detection of an odd number of photons.

  4. Confusion between Odds and Probability, a Pandemic?

    ERIC Educational Resources Information Center

    Fulton, Lawrence V.; Mendez, Francis A.; Bastian, Nathaniel D.; Musal, R. Muzaffer

    2012-01-01

    This manuscript discusses the common confusion between the terms probability and odds. To emphasize the importance and responsibility of being meticulous in the dissemination of information and knowledge, this manuscript reveals five cases of sources of inaccurate statistical language imbedded in the dissemination of information to the general…

  5. Superdeformation studies in the odd-odd nucleus {sup 192}Tl

    SciTech Connect

    Fischer, S.; Carpenter, M.P.; Janssens, R.V.F.

    1995-08-01

    The study of yrast and near-yrast structures of odd-odd nuclei to high spins is somewhat limited due to the complexity of the spectra resulting from the many proton-neutron couplings near the Fermi surface. In superdeformed nuclei, the number of available protons and neutrons near the Fermi surface is somewhat limited due to the presence of large-shell gaps which stabilize the nuclear shape. A relatively small number of available neutron and proton configurations can lead to fragmentation of the SD intensity into a number of different bands. Two good examples of this phenomenon were found in {sup 192}Tl and {sup 194}Tl where the presence of six superdeformed bands were reported in both nuclei. We reexamined {sup 192}Tl at Gammasphere using the {sup 160}Gd({sup 37}Cl,5n) reaction at 178 MeV to populate states in the superdeformed well of this nucleus. While our previous study on {sup 192}Tl at ATLAS was very successful, a number of questions remained which formed the basis of our objectives in this experiment: obtain better {gamma}-ray energies for the known transitions and identify higher spin members in each band; determine how the bands feed the known yrast states in {sup 192}Tl as well as determine the complete spectrum in coincidence with the SD bands; look for M1 transitions connecting proposed signature partners; and attempt to identify other excitations in the superdeformed well. Analysis is underway and four of the six bands were confirmed. The reasons that two of the reported bands were not observed in this latest work is still under investigation. As of this time, no other superdeformed bands were identified in the data. Two of the confirmed SD bands have a constant moment of inertia and show indications of cross-talk between each other. This observation is not unexpected since the calculated M1 rates for the proposed configuration of the band, {pi}{sub 13/2} x {upsilon}j{sub 15/2}, indicate that M1 transitions linking the two SD bands should be observed.

  6. Latino High School Graduation. Defying the Odds.

    ERIC Educational Resources Information Center

    Romo, Harriett D.; Falbo, Toni

    This book describes how "at-risk" Hispanic youth defy the odds and stay in school to earn a high school diploma. Information about success is needed because Hispanic youth drop out at about twice the rate of non-Hispanic Whites. The discussion is based on the results of a 4-year longitudinal study of 100 Hispanic youth labeled at-risk by their…

  7. Stratospheric distributions of odd nitrogen and odd hydrogen in a two-dimensional model

    NASA Technical Reports Server (NTRS)

    Prinn, R. G.; Alyea, F. N.; Cunnold, D. M.

    1975-01-01

    A two-dimensional pole-to-pole chemical model of the stratosphere is developed which extends from 8 to 38 km in altitude. Atmospheric motions are simulated by mean vertical and meridional winds and eddy diffusion coefficients. Seasonally averaged distributions of important odd nitrogen (NO, NO2, and HNO3) and odd hydrogen (H, OH, HO2, H2O2) compounds are computed. Photodissociation of N2O leads to production of odd nitrogen in the stratosphere, and the odd nitrogen is ultimately removed by downward transport into the troposphere and by rain-out (modeled by a rain-out lifetime of 30 days below 8-km altitude). Results are presented for a quasi-steady state in which seasonal cycles repeat themselves. These results show significant latitudinal as well as vertical variations in the predicted species which emphasize the need for at least two dimensions in accurate stratospheric modeling. Computed concentrations are compared with observations when they exist.

  8. Body mass index, waist circumference and waist-to-hip ratio: which anthropometric indicator is better predictor for the hypertension development in women population of the island Cres.

    PubMed

    Kabalin, Milena; Kolarić, Branko; Marchesi, Vanja Vasiljev; Pereza, Nina; Ostojić, Sasa; Rukavina, Tomislav; Kapović, Miljenko

    2012-06-01

    The aim of this research was to investigate the prevalence of obesity and high blood pressure and to prove which of three anthropometric indicators of obesity - waist circumference, body mass index (BMI) waist-to-hip ratio - is better predictor for the development of hypertension in women population of the island of Cres. We approached separately groups of women with measured high blood pressure and with previously diagnosed. The research was preformed within the research project "Genetic and biomedical characteristics of the population of the island of Cres". This was the cross sectional study and data were obtained on the sample of 247 females over 18 years old that voluntarily participated in this study. In our study group the prevalence of overweight was 39.0%, obesity 27.5%, increased waist circumference was present in 69.4% while increased blood pressure was found in 53.0% examinees. Our results indicate that age, BMI, impaired glucose concentration and serum cholesterol could be considered as predictors for the development of arterial hypertension, whether measured or previously diagnosed. PMID:22856216

  9. Odd top partners at the LHC

    NASA Astrophysics Data System (ADS)

    Anandakrishnan, Archana; Collins, Jack H.; Farina, Marco; Kuflik, Eric; Perelstein, Maxim

    2016-04-01

    LHC searches for fermionic top partners T focus on three decay topologies: T →b W , T →t Z , and T →t h . However, top partners may carry new conserved quantum numbers that forbid these decays. The simplest possibility is a conserved parity, under which the top partner is odd and all SM states are even. In this case, decays of top partners may involve new particle-odd scalars, leading to signal topologies more commonly associated with supersymmetry, either with or without R -parity conservation. We study a simplified model in which this possibility is realized, and estimate the bounds on the top partner mass in this model implied by LHC searches for supersymmetry. We find that the bounds can be significantly weaker than in the conventional top partner decay scenario. For example, if the new parity is exact, a 500 GeV top partner is allowed as long as the lightest parity-odd scalar mass is between 325 and 500 GeV. The lower allowed top partner mass reduces the need for fine-tuning in the Higgs mass parameter, compared to the conventional decay scenario. We also present an explicit model, the oddest little Higgs, which exhibits this phenomenology.

  10. Study of Even-Even/Odd-Even/Odd-Odd Nuclei in Zn-Ga-Ge Region in the Proton-Neutron IBM/IBFM/IBFFM

    SciTech Connect

    Yoshida, N.; Brant, S.; Zuffi, L.

    2009-08-26

    We study the even-even, odd-even and odd-odd nuclei in the region including Zn-Ga-Ge in the proton-neutron IBM and the models derived from it: IBM2, IBFM2, IBFFM2. We describe {sup 67}Ga, {sup 65}Zn, and {sup 68}Ga by coupling odd particles to a boson core {sup 66}Zn. We also calculate the beta{sup +}-decay rates among {sup 68}Ge, {sup 68}Ga and {sup 68}Zn.

  11. Comparative study of Gamow-Teller strength distributions in the odd-odd nucleus {sup 50}V and its impact on electron capture rates in astrophysical environments

    SciTech Connect

    Nabi, Jameel-Un; Sajjad, Muhammad

    2007-11-15

    Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus {sup 50}V by using the pn-QRPA theory. At present {sup 50}V is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a {sup 50}V(d, {sup 2}He){sup 50}Ti experiment, with the earlier work of Fuller, Fowler, and Newman (referred to as FFN) and subsequently with the large-scale shell model calculations. One curious finding of the paper is that the Brink's hypothesis, usually employed in large-scale shell model calculations, is not a good approximation to use at least in the case of {sup 50}V. SNe Ia model calculations performed using FFN rates result in overproduction of {sup 50}Ti, and were brought to a much acceptable value by employing shell model results. It might be interesting to study how the composition of the ejecta using presently reported QRPA rates compare with the observed abundances.

  12. A Focus on Variation in Morphology of Soft Palate Using Cone-Beam Computed Tomography with Assessment of Need’s Ratio in Central Madhya Pradesh Population

    PubMed Central

    Agrawal, Priyal; Phulambrikar, Tushar; Singh, Siddharth Kumar; Sharma, B.K.; Rodricks, Deepshikha

    2016-01-01

    Introduction Soft palate is an anatomical structure that helps in modifying the quality of voice and to breathe while swallowing. Through the variants and shapes of the soft palate, we can assess the age and gender of an individual. Aim The aim of the present study was to investigate the variation in morphology of soft palate and to find its association with the Need’s ratio, Velar Length (VL), Velar Width (VW) and Pharyngeal Depth (PD), in age groups and gender using CBCT in Central Madhya Pradesh population. Materials and Methods The study sample consisted of 121 CBCT scans of individuals aged between 15 to 45 years. These scans were retrieved from the Department of Oral Radiology. The velar morphology on CBCT was examined and grouped into six types. The results obtained were subjected to a statistical analysis to find the association between variants of the soft palate with gender and different age groups. ANOVA and Z-test were used for statistical analysis. The p≤0.05 was considered as significant while p≤0.001 was considered as highly significant. Results The most frequent type of soft palate was rat tail shaped. The mean VL and VW values were significantly higher in males while PD and Need’s ratio were higher among females, insignificantly associated with the types of soft palate. A significant association was observed between the mean VL and VW with various age groups, showing an increase in values with an increase in age. Conclusion A variation in morphology of soft palate plays an important role in the assessment of velopharyngeal closure and in diagnosing obstructive sleep apnoea individuals. PMID:27054128

  13. Odd-parity D states in He.

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.

    1972-01-01

    The states considered lie below the n = 2 threshold of He(+) and decay radiatively to the lower states. The most general D-state wave function of odd parity of two electrons is examined. The results presented are optimized with respect to four nonlinear parameters for 112 terms. A mass-polarization correction is given for all the states listed. The positions of the D states, including the reduced mass and the mass-polarization corrections, with respect to the ground state of He are reported.

  14. Enhanced T-odd, P-odd electromagnetic moments in reflection asymmetric nuclei

    SciTech Connect

    Spevak, V.; Auerbach, N.; Flambaum, V.V.

    1997-09-01

    Collective P- and T-odd moments produced by parity and time invariance violating forces in reflection asymmetric nuclei are considered. The enhanced collective Schiff, electric dipole, and octupole moments appear due to the mixing of rotational levels of opposite parity. These moments can exceed single-particle moments by more than 2 orders of magnitude. The enhancement is due to the collective nature of the intrinsic moments and the small energy separation between members of parity doublets. In turn these nuclear moments induce enhanced T- and P-odd effects in atoms and molecules. A simple estimate is given and a detailed theoretical treatment of the collective T-, P-odd electric moments in reflection asymmetric, odd-mass nuclei is presented. In the present work we improve on the simple liquid drop model by evaluating the Strutinsky shell correction and include corrections due to pairing. Calculations are performed for octupole deformed long-lived odd-mass isotopes of Rn, Fr, Ra, Ac, and Pa and the corresponding atoms. Experiments with such atoms may improve substantially the limits on time reversal violation. {copyright} {ital 1997} {ital The American Physical Society}

  15. Empirical residual neutron-proton interaction in odd-odd nuclei

    NASA Astrophysics Data System (ADS)

    Wu, Zheying; Changizi, S. A.; Qi, Chong

    2016-03-01

    Two types of average neutron-proton interaction formulas are compared: In the first type, neutron-proton interactions for even-even and odd-A nuclei extracted from experimental binding energies show a smooth behavior as a function of mass number A and are dominated by the contribution from the symmetry energy. Whereas in the second type large systematic staggering is seen between even-A and odd-A nuclei. This deviation is understood in terms of the additional neutron-proton interaction in odd-odd nuclei relative to the neighboring even-even and odd-A systems. We explore three possible ways to extract this additional interaction from the binding energy difference of neighboring nuclei. The extracted interactions are positive in nearly all cases and show weak dependence on the mass number. The empirical interactions are also compared with theoretical values extracted from recent nuclear mass models where large unexpected fluctuations are seen in certain nuclei. The reproduction of the residual neutron-proton interaction and the correction of those irregular fluctuations can be a good criterion for the refinement of those mass models.

  16. Effect of Saccharomyces cerevisiae on alfalfa nutrient degradation characteristics and rumen microbial populations of steers fed diets with different concentrate-to-forage ratios.

    PubMed

    Ding, Gengzhi; Chang, Ying; Zhao, Liping; Zhou, Zhenming; Ren, Liping; Meng, Qingxiang

    2014-01-01

    Live yeast (Saccharomyces cerevisiae) constitutes an effective additive for animal production; its probiotic effect may be related to the concentrate-to-forage ratio (CTFR). The objective of this study was to assess the effects of S. cerevisiae (SC) on fiber degradation and rumen microbial populations in steers fed diets with different levels of dietary concentrate. Ten Simmental × Local crossbred steers (450 ± 50 kg BW) were assigned to a control group or an SC group. Both groups were fed the same basal diet but the SC group received SC supplementation (8 × 10(9) cfu/h/d through the ruminal fistula) following a two-period crossover design. Each period consisted of four phases, each of which lasted 17 d: 10 d for dietary adaptation, 6 d for degradation study, and 1 d for rumen sample collection. From the 1(st) to the 4(th) phase, steers were fed in a stepwise fashion with increasing CTFRs, i.e., 30:70, 50:50, 70:30, and 90:10. The kinetics of dry matter and fiber degradation of alfalfa pellets were evaluated; the rumen microbial populations were detected using real-time PCR. The results revealed no significant (P > 0.05) interactions between dietary CTFR and SC for most parameters. Dietary CTFR had a significant effect (P < 0.01) on degradation characteristics of alfalfa pellets and the copies of rumen microorganism; the increasing concentrate level resulted in linear, quadratic or cubic variation trend for these parameters. SC supplementation significantly (P < 0.05) affected dry matter (DM) and neutral detergent fiber (NDF) degradation rates (c DM, c NDF) and NDF effective degradability (EDNDF). Compared with the control group, there was an increasing trend of rumen fungi and protozoa in SC group (P < 0.1); copies of total bacteria in SC group were significantly higher (P < 0.05). Additionally, percentage of Ruminobacter amylophilus was significantly lower (P < 0.05) but percentage of Selenomonas ruminantium was

  17. Effect of Saccharomyces cerevisiae on alfalfa nutrient degradation characteristics and rumen microbial populations of steers fed diets with different concentrate-to-forage ratios

    PubMed Central

    2014-01-01

    Live yeast (Saccharomyces cerevisiae) constitutes an effective additive for animal production; its probiotic effect may be related to the concentrate-to-forage ratio (CTFR). The objective of this study was to assess the effects of S. cerevisiae (SC) on fiber degradation and rumen microbial populations in steers fed diets with different levels of dietary concentrate. Ten Simmental × Local crossbred steers (450 ± 50 kg BW) were assigned to a control group or an SC group. Both groups were fed the same basal diet but the SC group received SC supplementation (8 × 109 cfu/h/d through the ruminal fistula) following a two-period crossover design. Each period consisted of four phases, each of which lasted 17 d: 10 d for dietary adaptation, 6 d for degradation study, and 1 d for rumen sample collection. From the 1st to the 4th phase, steers were fed in a stepwise fashion with increasing CTFRs, i.e., 30:70, 50:50, 70:30, and 90:10. The kinetics of dry matter and fiber degradation of alfalfa pellets were evaluated; the rumen microbial populations were detected using real-time PCR. The results revealed no significant (P > 0.05) interactions between dietary CTFR and SC for most parameters. Dietary CTFR had a significant effect (P < 0.01) on degradation characteristics of alfalfa pellets and the copies of rumen microorganism; the increasing concentrate level resulted in linear, quadratic or cubic variation trend for these parameters. SC supplementation significantly (P < 0.05) affected dry matter (DM) and neutral detergent fiber (NDF) degradation rates (cDM, cNDF) and NDF effective degradability (EDNDF). Compared with the control group, there was an increasing trend of rumen fungi and protozoa in SC group (P < 0.1); copies of total bacteria in SC group were significantly higher (P < 0.05). Additionally, percentage of Ruminobacter amylophilus was significantly lower (P < 0.05) but percentage of Selenomonas ruminantium was significantly

  18. Sigma decomposition: the CP-odd Lagrangian

    NASA Astrophysics Data System (ADS)

    Hierro, I. M.; Merlo, L.; Rigolin, S.

    2016-04-01

    In Alonso et al., JHEP 12 (2014) 034, the CP-even sector of the effective chiral Lagrangian for a generic composite Higgs model with a symmetric coset has been constructed, up to four momenta. In this paper, the CP-odd couplings are studied within the same context. If only the Standard Model bosonic sources of custodial symmetry breaking are considered, then at most six independent operators form a basis. One of them is the weak- θ term linked to non-perturbative sources of CP violation, while the others describe CP-odd perturbative couplings between the Standard Model gauge bosons and an Higgs-like scalar belonging to the Goldstone boson sector. The procedure is then applied to three distinct exemplifying frameworks: the original SU(5)/SO(5) Georgi-Kaplan model, the minimal custodial-preserving SO(5)/SO(4) model and the minimal SU(3)/(SU(2) × U(1)) model, which intrinsically breaks custodial symmetry. Moreover, the projection of the high-energy electroweak effective theory to the low-energy chiral effective Lagrangian for a dynamical Higgs is performed, uncovering strong relations between the operator coefficients and pinpointing the differences with the elementary Higgs scenario.

  19. Meissner effect of odd-frequency superconductors

    NASA Astrophysics Data System (ADS)

    Hashimoto, Katsufumi

    2001-10-01

    We present theoretical results on the Meissner effect of odd-frequency superconductors with the order parameter of the form, sgn(ωn)φ(k,iωn), where φ(k,iωn) is even in the Matsubara frequency ωn as in the conventional case. It is shown that the spectral function of the anomalous Green's function is given in the form of the Hilbert transformation of the one for the even-frequency part, and the anomalous contribution to the paramagnetic kernel consists of the conventional term but with the opposite sign and a term expressed by the digamma function. In the static limit the latter term reduces to twice the former one with the opposite sign so that the net contribution becomes the same as the conventional one. This indicates the presence of the Meissner effect for this class of the odd-frequency superconductors. A model interaction is discussed that leads to the order parameter mentioned above.

  20. Soil clay content underlies prion infection odds

    USGS Publications Warehouse

    David, Walter W.; Walsh, D.P.; Farnsworth, Matthew L.; Winkelman, D.L.; Miller, M.W.

    2011-01-01

    Environmental factors-especially soil properties-have been suggested as potentially important in the transmission of infectious prion diseases. Because binding to montmorillonite (an aluminosilicate clay mineral) or clay-enriched soils had been shown to enhance experimental prion transmissibility, we hypothesized that prion transmission among mule deer might also be enhanced in ranges with relatively high soil clay content. In this study, we report apparent influences of soil clay content on the odds of prion infection in free-ranging deer. Analysis of data from prion-infected deer herds in northern Colorado, USA, revealed that a 1% increase in the clay-sized particle content in soils within the approximate home range of an individual deer increased its odds of infection by up to 8.9%. Our findings suggest that soil clay content and related environmental properties deserve greater attention in assessing risks of prion disease outbreaks and prospects for their control in both natural and production settings. ?? 2011 Macmillan Publishers Limited. All rights reserved.

  1. Transmission ratio distortion of molecular markers in a doubled haploid population originated from a natural hybrid between Osmunda japonica and O. lancea.

    PubMed

    Yatabe-Kakugawa, Yoko; Tsutsumi, Chie; Hirayama, Yumiko; Tsuneki, Shizuka; Murakami, Noriaki; Kato, Masahiro

    2013-07-01

    In ferns, intra-gametophytic selfing occurs as a mode of reproduction where two gametes from the same gametophyte form a completely homozygous sporophyte. Intra-gametophytic selfing is considered to be prevented by lethal or deleterious recessive genes in several diploid species. In order to investigate the modes and tempo of selection acting different developmental stages, doubled haploids obtained from intra-gametophytic selfing within isolated gametophytes of a putative F1 hybrid between Osmunda japonica and O. lancea were analyzed with EST_derived molecular markers, and the distribution pattern of transmission ratio distortion (TRD) along linkage map was clarified. As the results, the markers with skewness were clustered in two linkage groups. For the two highly distorted regions, gametophytes and F2 population were also examined. The markers skewed towards O. japonica on a linkage group (LG_2) showed skewness also in gametophytes, and the TRD was generated in the process of spore formation or growth of gametophytes. Also, selection appeared to be operating in the gametophytic stage. The markers on other linkage group (LG_11) showed highest skewness towards O. lancea in doubled haploids, and it was suggested that the segregation of LG_11 were influenced by zygotic lethality or genotypic evaluation and that some deleterious recessive genes exist in LG_11 and reduce the viability of homozygotes with O. japonica alleles. It is very likely that a region of LG_11were responsible for the low frequencies of intra-gametophytic selfing in O. japonica. PMID:23224293

  2. Effect of odd hydrogen on ozone depletion by chlorine reactions

    NASA Technical Reports Server (NTRS)

    Donahue, T. M.; Cicerone, R. J.; Liu, S. C.; Chameides, W. L.

    1976-01-01

    The present paper discusses how the shape of the ozone layer changes under the influence of injected ClX for several choices of two key HOx reaction rates. The two HOx reactions are: OH + HO2 yields H2O + O2 and O + HO2 yields OH + O2. Results of calculations are presented which show that the two reaction rates determine the stratospheric concentrations of OH and HO2, and that these concentrations regulate the amount by which the stratospheric ozone column can be reduced due to injections of odd chlorine. It is concluded that the amount of ozone reduction by a given mixing ratio of ClX will remain very uncertain until the significance of several possible feedback effects involving HOx in a chlorine-polluted atmosphere are determined and measurements of the reaction rates and HOx concentrations are made at the relevant temperatures.

  3. Shell Model Description of the Odd-Odd Co and Cu Nuclei

    SciTech Connect

    Medina, N. H.; Allegro, P. R. P.; Oliveira, J. R. B. de; Ribas, R. V.; Seale, W. A.; Toufen, D. L.; Silveira, M. A. G.

    2007-10-26

    The known excited states of the odd-odd nuclei {sup 54,56,58,60}Co and 60,62,64,66Cu were interpreted in the framework of the large scale shell model (LSSM), using several effective interactions and configuration spaces. For the description of the negative parity states, we have allowed one particle excitation to the g{sub 9/2} orbital. The LSSM using the GXPF1 effective interaction reproduces well the first excited states in all of these nuclei.

  4. Comparison of model results transporting the odd nitrogen family with results transporting separate odd nitrogen species

    NASA Technical Reports Server (NTRS)

    Douglass, Anne R.; Jackman, Charles H.; Stolarski, Richard S.

    1989-01-01

    A fast two-dimensional residual circulation stratospheric family transport model, designed to minimize computer requirements, is developed. The model was used to calculate the ambient and perturbed atmospheres in which odd nitrogen species are transported as a family, and the results were compared with calculations in which HNO3, N2O5, ClONO2, and HO2NO2 are transported separately. It was found that ozone distributions computed by the two models for a present-day atmosphere are nearly identical. Good agreement was also found between calculated species concentrations and the ozone response, indicating the general applicability of the odd-nitrogen family approximations.

  5. Proton emission from the deformed odd-odd nuclei near drip line

    NASA Astrophysics Data System (ADS)

    Patial, M.; Arumugam, P.; Jain, A. K.; Maglione, E.; Ferreira, L. S.

    2016-01-01

    Proton emission from odd-odd nuclei is studied within the two quasiparticle plus rotor model which includes the non-adiabatic effects and the residual interaction between valence proton and neutron. Justification of the formalism is discussed through corroboration of our results with the experimental spectrum of 180Ta. Exact calculations are performed to get the proton emission halflives. Our results for the proton emitter 130Eu leads to the assignment of spin and parity Jπ = 1+ for the ground state. The role of Coriolis and residual neutron-proton interactions on the proton emission halflives and their interplay are also discussed.

  6. Odd perfect numbers have at least nine distinct prime factors

    NASA Astrophysics Data System (ADS)

    Nielsen, Pace P.

    2007-12-01

    An odd perfect number, N , is shown to have at least nine distinct prime factors. If 3nmid N then N must have at least twelve distinct prime divisors. The proof ultimately avoids previous computational results for odd perfect numbers.

  7. W${'}$ signatures with odd Higgs particles

    SciTech Connect

    Dobrescu, Bogdan A.; Peterson, Andrea D.

    2014-08-13

    We point out that W' bosons may decay predominantly into Higgs particles associated with their broken gauge symmetry. We demonstrate this in a renormalizable model where the W' and W couplings to fermions differ only by an overall normalization. This "meta-sequential" W' boson decays into a scalar pair, with the charged one subsequently decaying into a W boson and a neutral scalar. These scalars are odd under a parity of the Higgs sector, which consists of a complex bidoublet and a doublet. Finally, the W' and Z' bosons have the same mass and branching fractions into scalars, and may show up at the LHC in final states involving one or two electroweak bosons and missing transverse energy.

  8. W$${'}$$ signatures with odd Higgs particles

    DOE PAGESBeta

    Dobrescu, Bogdan A.; Peterson, Andrea D.

    2014-08-13

    We point out that W' bosons may decay predominantly into Higgs particles associated with their broken gauge symmetry. We demonstrate this in a renormalizable model where the W' and W couplings to fermions differ only by an overall normalization. This "meta-sequential" W' boson decays into a scalar pair, with the charged one subsequently decaying into a W boson and a neutral scalar. These scalars are odd under a parity of the Higgs sector, which consists of a complex bidoublet and a doublet. Finally, the W' and Z' bosons have the same mass and branching fractions into scalars, and may showmore » up at the LHC in final states involving one or two electroweak bosons and missing transverse energy.« less

  9. Executive Functioning Deficits in Relation to Symptoms of ADHD and/or ODD in Preschool Children

    ERIC Educational Resources Information Center

    Thorell, Lisa B.; Wahlstedt, Cecilia

    2006-01-01

    The present study investigated the relation between executive functioning and symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD) in children aged 4-6. A population-based sample (n = 201) was used and laboratory measures of inhibition, working memory and verbal fluency and teacher ratings of…

  10. Against All Odds: Genocidal Trauma Is Associated with Longer Life-Expectancy of the Survivors

    PubMed Central

    Sagi-Schwartz, Abraham; Bakermans-Kranenburg, Marian J.; Linn, Shai; van IJzendoorn, Marinus H.

    2013-01-01

    Does surviving genocidal experiences, like the Holocaust, lead to shorter life-expectancy? Such an effect is conceivable given that most survivors not only suffered psychosocial trauma but also malnutrition, restriction in hygienic and sanitary facilities, and lack of preventive medical and health services, with potentially damaging effects for later health and life-expectancy. We explored whether genocidal survivors have a higher risk to die younger than comparisons without such background. This is the first population-based retrospective cohort study of the Holocaust, based on the entire population of immigrants from Poland to Israel (N = 55,220), 4–20 years old when the World War II started (1939), immigrating to Israel either between 1945 and 1950 (Holocaust group) or before 1939 (comparison group; not exposed to the Holocaust). Hazard of death – a long-term outcome of surviving genocidal trauma – was derived from the population-wide official data base of the National Insurance Institute of Israel. Cox regression yielded a significant hazard ratio (HR = 0.935, CI (95%) = 0.910–0.960), suggesting that the risk of death was reduced by 6.5 months for Holocaust survivors compared to non-Holocaust comparisons. The lower hazard was most substantial in males who were aged 10–15 (HR = 0.900, CI (95%) = 0.842–0.962, i.e., reduced by 10 months) or 16–20 years at the onset of the Holocaust (HR = 0.820, CI (95%) = 0.782–0.859, i.e., reduced by18 months). We found that against all odds genocidal survivors were likely to live longer. We suggest two explanations: Differential mortality during the Holocaust and “Posttraumatic Growth” associated with protective factors in Holocaust survivors or in their environment after World War II. PMID:23894427

  11. Even-odd effects in Z and N distributions of fragments emitted at intermediate energies

    SciTech Connect

    Lombardo, I.; Lanzalone, G.; Agodi, C.; Amorini, F.; Anzalone, A.; Han, J.; Maiolino, C.; Auditore, L.; Loria, D.; Trifiro, A.; Trimarchi, M.; Berceanu, I.; Cardella, G.; De Filippo, E.; Pagano, A.; Papa, M.; Pirrone, S.; Cavallaro, S.; Porto, F.; Rizzo, F.

    2011-08-15

    Even-odd effects in Z and N distributions of light fragments emitted at forward angles in nuclear collisions {sup 40}Ca + {sup 40}Ca, {sup 40}Ca + {sup 48}Ca, and {sup 48}Ca + {sup 48}Ca at 25 MeV/nucleon and identified in charge and mass with the Chimera multidetector have been analyzed. The amplitude of even-odd staggering effects seems to be related to the neutron to proton ratio N/Z of the entrance channels. A qualitative explanation of this effect, taking into account the deexcitation phase of primary excited fragments, is discussed.

  12. The ODD protocol: A review and first update

    USGS Publications Warehouse

    Grimm, Volker; Berger, Uta; DeAngelis, Donald L.; Polhill, J. Gary; Giske, Jarl; Railsback, Steve F.

    2010-01-01

    The 'ODD' (Overview, Design concepts, and Details) protocol was published in 2006 to standardize the published descriptions of individual-based and agent-based models (ABMs). The primary objectives of ODD are to make model descriptions more understandable and complete, thereby making ABMs less subject to criticism for being irreproducible. We have systematically evaluated existing uses of the ODD protocol and identified, as expected, parts of ODD needing improvement and clarification. Accordingly, we revise the definition of ODD to clarify aspects of the original version and thereby facilitate future standardization of ABM descriptions. We discuss frequently raised critiques in ODD but also two emerging, and unanticipated, benefits: ODD improves the rigorous formulation of models and helps make the theoretical foundations of large models more visible. Although the protocol was designed for ABMs, it can help with documenting any large, complex model, alleviating some general objections against such models.

  13. Redistribution of reactive odd nitrogen in the lower arctic stratosphere

    NASA Technical Reports Server (NTRS)

    Huebler, G.; Fahey, D. W.; Kelly, K. K.; Montzka, D. D.; Carroll, M. A.; Tuck, A. F.; Heidt, L. E.; Pollock, W. H.; Gregory, G. L.; Vedder, J. F.

    1990-01-01

    In-situ measurements of total reactive odd nitrogen NO(y), were made from the NASA DC-8 aircraft in the lower arctic stratosphere during the 1989 Airborne Arctic Stratospheric Expedition. Throughout January and February, NO(y) mixing ratios were typically between 0.5 and 3 parts per billion by volume (ppbv) at altitudes between 10 and 12.5 km. During several flights late in the mission, events of unusually light NO(y) occurred with mixing ratios up to 12 ppbv at these altitudes. Simultaneous measurements of N2O, O3, and H2O during these events suggest that large changes in NO(y) are not expected. The elevated NO(y) values are interpreted as a vertical redistribution of NO(y) in the lower stratosphere resulting from gravitational sedimentation of aerosol particles containing HNO3. No evidence of the redistribution of H2O is noted, consistent with observations of denitrification without dehydration higher in the stratosphere.

  14. Meeting report for "OddPols" 2014: the odds invite an even.

    PubMed

    Roy-Engel, Astrid M

    2015-02-01

    The Ninth International Biennial Conference on RNA Polymerases I and III (the "OddPols") was held on June 19-21, 2014 at the University of Michigan, Ann Arbor, USA. Sponsored by New England Biolabs, the Cayman Chemical Company, the Rackham Graduate School and the University of Michigan Health System, and organized by David Engelke, Craig Pikaard, Lawrence Rothblum, Andrzej Wierzbicki and Astrid Engel. This year at the conference, the "odds" were increased by expanding the usual topics on the advances in RNA polymerases I and III research to include presentations on RNA polymerase IV and V. The keynote speaker, Craig Pikaard, opened the meeting with his presentation entitled "Five nuclear multisubunit RNA polymerases". The meeting drew attendees from fourteen countries that shared their research discoveries through oral and poster presentations. The talks were organized into 11 sessions covering seven distinct topics. Here we present some of the highlights from the meeting using summaries provided by the participants. PMID:25445280

  15. Chiral Symmetry and Signature Splitting in Odd-Odd Neutron deficient Pr Nuclei

    NASA Astrophysics Data System (ADS)

    Fetea, Mirela; Nikolova, Veronika; Crider, Benjamin

    2004-10-01

    Over the past few years, sufficient data have been accumulated to enable a meaningful study of the systematic trends in nuclei far from stability. While general characteristics seen in experiments are understood by various mean-field nuclear models, there are key features that are not fully explained. Of particular interest are the chiral symmetry (chiral bands) and signature splitting/inversion phenomena. We report on our investigation on the association of signature inversion in an odd-odd band of two quasiparticles pointed along different axes with the formation of chiral twin bands, and understanding systematic chiral symmetry and signature splitting/inversion features within the framework of particle rotor model for neutron deficient Pr nuclei. This work was supported by the NSF Grant No. PHY 0204811 and U.S. Research Corporation Grant No. CC5494.

  16. Isospin and deformation studies in the odd-odd N=Z nucleus {sup 54}Co

    SciTech Connect

    Rudolph, D.; Andersson, L.-L.; Ekman, J.; Erten, O.; Fahlander, C.; Johansson, E. K.; Andreoiu, C.; Bengtsson, R.; Ragnarsson, I.; Bentley, M. A.; Williams, S. J.; Carpenter, M. P.; Seweryniak, D.; Charity, R. J.; Reviol, W.; Sarantites, D. G.; Clark, R. M.; Fallon, P.; Macchiavelli, A. O.; Svensson, C. E.

    2010-11-15

    High-spin states in the odd-odd N=Z nucleus {sup 54}Co have been investigated by the fusion-evaporation reaction {sup 28}Si({sup 32}S,1{alpha}1p1n){sup 54}Co. Gamma-ray information gathered with the Ge detector array Gammasphere was correlated with evaporated particles detected in the charged particle detector system Microball and a 1{pi} neutron detector array. A significantly extended excitation scheme of {sup 54}Co is presented, which includes a candidate for the isospin T=1, 6{sup +} state of the 1f{sub 7/2}{sup -2} multiplet. The results are compared to large-scale shell-model calculations in the fp shell. Effective interactions with and without isospin-breaking terms have been used to probe isospin symmetry and isospin mixing. A quest for deformed high-spin rotational cascades proved negative. This feature is discussed by means of cranking calculations.

  17. Influence of Traxiality on the Signature Inversion in Odd Odd Nuclei

    NASA Astrophysics Data System (ADS)

    Zheng, Ren-Rong; Zhu, Shun-Quan; Luo, Xiang-Dong; Janos, Timár; Andree, Gizon; Jean, Gizon; Sohler, D.; Nyakó M., B.; Zolnai, L.; Paul S., E.

    2004-08-01

    The nature of signature inversion in the pig9/2nuh11/2 bands of odd-odd 98,102Rh nuclei is studied. Calculations are performed by using a triaxial rotor plus two-quasiparticle model and are compared with the experimentally observed signature inversions. The calculations reproduce well the observations and suggest that, in these bands, the signature inversion can be interpreted mainly as a competition between the Coriolis and the proton-neutron residual interactions in low K space. The triaxiality applied in the Hamiltonian enlarges the amplitudes of high spin signature zigzags at small triaxial deformation and might push the signature inversion point to higher spin at large triaxial deformation.

  18. Structure of the yrast band in the odd-odd deformed nucleus {sup 156}Pm

    SciTech Connect

    Sood, P. C.; Sai, K. Vijay; Gowrishankar, R.; Sainath, M.

    2011-05-15

    The six-level sequence deduced for the odd-odd nucleus {sup 156}Pm in the high-spin studies following spontaneous fission of {sup 252}Cf is shown to constitute the K{sup {pi}=}4{sup +} yrast band having the two-quasiparticle configuration {l_brace}p:5/2[532]+ n:3/2[521]{r_brace}. Spin parities I{sup {pi}=}4{sup +} through 9{sup +} are assigned to the earlier suggested six levels. The location and the decay {gamma}'s of the 10{sup +} level of this band are indicated. It is also pointed out that there are no {gamma} rays common to these postfission high-spin spectra and those seen in the {sup 156}Nd {beta}-decay studies.

  19. Large odd{endash}even effect in RbC{sup {minus}}{sub {ital n}} cluster size distributions

    SciTech Connect

    Vandenbosch, R.; Will, D.I.

    1996-04-01

    RbC{sub {ital n}} cluster anions have been produced by Rb sputtering of graphite. The intensity ratio of clusters with an even number of carbon atoms to those with an odd number of carbons is much larger for RbC{sup {minus}}{sub {ital n}} clusters than for C{sup {minus}}{sub {ital n}} clusters. {ital Ab} {ital initio} quantum mechanical calculations suggest that this arises from RbC{sub {ital n}} electron affinities that are close to zero or negative for odd {ital n}, rather than from an enhanced odd{endash}even alternation in the affinities. {copyright} {ital 1996 American Institute of Physics.}

  20. Odd frequency pairing of interacting Majorana fermions

    NASA Astrophysics Data System (ADS)

    Huang, Zhoushen; Woelfle, Peter; Balatsky, Alexandar

    Majorana fermions are rising as a promising key component in quantum computation. While the prevalent approach is to use a quadratic (i.e. non-interacting) Majorana Hamiltonian, when expressed in terms of Dirac fermions, generically the Hamiltonian involves interaction terms. Here we focus on the possible pair correlations in a simple model system. We study a model of Majorana fermions coupled to a boson mode and show that the anomalous correlator between different Majorana fermions, located at opposite ends of a topological wire, exhibits odd frequency behavior. It is stabilized when the coupling strength g is above a critical value gc. We use both, conventional diagrammatic theory and a functional integral approach, to derive the gap equation, the critical temperature, the gap function, the critical coupling, and a Ginzburg-Landau theory allowing to discuss a possible subleading admixture of even-frequency pairing. Work supported by USDOE DE-AC52-06NA25396 E304, Knut and Alice Wallenberg Foundation, and ERC DM-321031.

  1. Multiply enhanced odd-order wave-mixing spectroscopy.

    PubMed

    Mathew, Nathan A; Block, Stephen B; Yurs, Lena A; Kornau, Kathryn M; Pakoulev, Andrei V; Wright, John C

    2009-12-01

    Extending current coherent multidimensional spectroscopy (CMDS) methods to higher order multiwave mixing requires excitation intensities where dynamic Stark effects become important. This paper examines the dynamic Stark effects that occur in mixed frequency/time domain CMDS methods at high excitation intensities in a model system with an isolated vibrational state. The phase-matching restrictions in CMDS define the excitation beams that interact by nonlinear mixing while the dynamic Stark effects create vibrational ladders of increasingly more energetic overtone and combination band states. The excited quantum states form coherences that reemit the output beams. This paper uses the phase-matching conditions k(out) = k(1) - k(2) + k(2') and k(out) =- k(1) + k(2) + k(2'), where the subscripts denote the excitation frequencies of each excitation pulse and the output pulse. The phase-matching condition constrains each pulse to have an odd number of interactions so the overall mixing process that creates the output coherence must also involve an odd number of interactions. Tuning the excitation frequencies and spectrally resolving the output intensity creates three-dimensional spectra that resolve the individual overtone states. Changing the excitation pulse time delays measures the dynamics of the coherences and populations created by the multiple excitations. The multidimensional spectra probe the highly excited states of a molecular potential energy surface. This paper uses tungsten hexacarbonyl (W(CO)(6)) as a model for observing how dynamic Stark effects change the multidimensional spectra of a simple system. The simplicity of the W(CO)(6) system provides the experimental data required to develop the nonperturbative theoretical methods that will be necessary to model this new approach to CMDS. PMID:19860444

  2. THE RELATION BETWEEN DYNAMICAL MASS-TO-LIGHT RATIO AND COLOR FOR MASSIVE QUIESCENT GALAXIES OUT TO z ∼ 2 AND COMPARISON WITH STELLAR POPULATION SYNTHESIS MODELS

    SciTech Connect

    Van de Sande, Jesse; Franx, Marijn; Kriek, Mariska; Bezanson, Rachel; Van Dokkum, Pieter G.

    2015-02-01

    We explore the relation between the dynamical mass-to-light ratio (M/L) and rest-frame color of massive quiescent galaxies out to z ∼ 2. We use a galaxy sample with measured stellar velocity dispersions in combination with Hubble Space Telescope and ground-based multi-band photometry. Our sample spans a large range in log M {sub dyn}/L {sub g} (of 1.6 dex) and log M {sub dyn}/L {sub K} (of 1.3 dex). There is a strong, approximately linear correlation between the M/L for different wavebands and rest-frame color. The root-mean-square scatter in log M {sub dyn}/L residuals implies that it is possible to estimate the M/L with an accuracy of ∼0.25 dex from a single rest-frame optical color. Stellar population synthesis (SPS) models with a Salpeter stellar initial mass function (IMF) cannot simultaneously match M {sub dyn}/L {sub g} versus (g – z){sub rest-frame} and M {sub dyn}/L {sub K} versus (g – K){sub rest-frame}. By changing the slope of the IMF we are still unable to explain the M/L of the bluest and reddest galaxies. We find that an IMF with a slope between α = 2.35 and α = 1.35 provides the best match. We also explore a broken IMF with a Salpeter slope at M < 1 M {sub ☉} and M > 4 M {sub ☉} and a slope α in the intermediate region. The data favor a slope of α = 1.35 over α = 2.35. Nonetheless, our results show that variations between different SPS models are comparable to the IMF variations. In our analysis we assume that the variation in M/L and color is driven by differences in age, and that other contributions (e.g., metallicity evolution, dark matter) are small. These assumptions may be an important source of uncertainty as galaxies evolve in more complex ways.

  3. Stimulant Use, Religiosity, and the Odds of Developing or Maintaining an Alcohol Use Disorder Over Time

    PubMed Central

    Borders, Tyrone F.; Booth, Brenda M.

    2013-01-01

    Objective: Little is known about whether cocaine or methamphetamine use, particularly among stimulant users residing in rural areas, is associated with increased odds of developing or maintaining an alcohol use disorder (AUD) over time. One factor that may help to protect some users against the development of an AUD is religiosity. This study examined how stimulant use and religiosity are associated longitudinally with the odds of an AUD among a rural population-based cohort of stimulant users. Method: Recent stimulant users (N = 710) were recruited via respondent-driven sampling and were interviewed every 6 months over a 3-year period. Concurrent and lagged generalized estimating equations analyses were conducted to estimate how past-30-day crack cocaine, powder cocaine, and methamphetamine use; religiosity; and other covariates were associated with the odds of an AUD. Results: At baseline, 56% of the participants met AUD criteria. The odds of an AUD declined significantly over time in the concurrent, but not the lagged, model. Crack cocaine use was associated with increased odds of an AUD in both models, although the strength of the concurrent association between an AUD and crack cocaine use declined over time. Powder cocaine use and more frequent church attendance also were concurrently associated with decreased odds of an AUD. Conclusions: Rural stimulant users, especially those using cocaine, could potentially benefit from treatment for both alcohol use and stimulant use. In addition, our findings suggest that greater frequency of church attendance may be related to lower odds of the development or maintenance of an AUD. PMID:23490565

  4. Construction of an odds model of coronary heart disease using published information: the Cardiovascular Health Improvement Model (CHIME)

    PubMed Central

    Martin, Christopher J; Taylor, Paul; Potts, Henry WW

    2008-01-01

    Background There is a need for a new cardiovascular disease model that includes a wider range of relevant risk factors, in particular lifestyle factors, to aid targeting of interventions and improve population models of the impact of cardiovascular disease and preventive strategies. The model needs to be applicable to a wider population including different ethnic groups, different countries and to those with and without cardiovascular disease. This paper describes the construction of the Cardiovascular Health Improvement Model that aims to meet these requirements. Method An odds model is used. Information was taken from 2003 mortality statistics for England and Wales, the Health Survey for England 2003 and published data on relative risk in those with and without CVD and mean blood pressure values in hypertensives. The odds ratios used were taken from the INTERHEART study. Results A worked example is given calculating the 10-year coronary heart disease risk for a 57 year-old non-diabetic male with no personal or family history of cardiovascular disease, who smokes 30 cigarettes a day and has a systolic blood pressure of 137 mmHg, a total cholesterol (TC) of 6.2 mmol/l, a high density lipoprotein (HDL) of 1.3 mol/l, and a body mass index of 21. He neither drinks regularly nor exercises. He can give no reliable information about his mental health or fruit and vegetable intake. His 10-year risk of CHD death is 2.47%. Conclusion This paper demonstrates a method for developing a CHD risk model. Further improvements could be made to the model with additional information. The method is applicable to other causes of death. PMID:18976488

  5. GT Strength in Odd-A Nuclei^*

    NASA Astrophysics Data System (ADS)

    Watson, J. W.; Du, Q. Q.

    1998-04-01

    We measured the complete set of polarization-transfer observables (D_ij) for the ^13C(p,n)^13N and ^15N(p,n)^15O reactions at 135 MeV. From the D_ijs we constructed the spin-independent, spin-longitudinal, and spin-transverse responses [1] D_0, D_q, Dn and D_p. From these responses we extracted, in a model-independent way, the Δ J=0 and Δ J=1 (``F'' and ``GT'') fractions of the J^π=1/2^-arrow1/2^- g.s. to g.s. transitions for these reactions. The ``F'' fraction, f_F=D_0(0^circ); the ``GT'' fraction, f_GT=D_q(0^circ)+D_n(0^circ)+D_p(0^circ)= 1- D_0(0^circ). The extracted GT fractions, f_GT, are substantially larger than one would predict from β-decay matrix elements and the systematics of the (p,n) reaction on even-A nuclei. These results confirm earlier, model-dependent determinations of f_GT obtained from the (p,n) reaction on ^13C, ^15N and ^39K at other energies [2], [3], [4], indicating that considerable caution must be used when extracting B(GT) matrix elements from odd-A (p,n) data. * Research supported in part by the U.S. NSF. [1] M. Ichimura, K. Kawahigashi, Phys. Rev. C 45 1822 (1992). [2] T. N. Taddeucci, C. A. Goulding, T. A. Carey, R. C. Byrd, C. D. Goodman, C. Gaarde, J. Larsen, D. Horen, J. Rapaport, and E. Sugarbaker, Nucl. Phys. A469 125 (1987). [3] H. Sakai, H. Okamura, N. Matsuoka, A. Shimizu, T. Suda, M. Ieiri and H. M. Shimizu, Nuclear Physics A579 45-61 (1994). [4] W. Huang, Ph.D. dissertation, Indiana U., 1991, (unpublished).

  6. Diabatic crossing of chiral "twins" in the odd-odd 106Ag nucleus: A theoretical perspective

    NASA Astrophysics Data System (ADS)

    Malik, Sham S.

    2016-07-01

    A systematic study of both the observed positive-parity magnetic rotation band and the negative-parity Δ I =1 doublet bands in an odd-odd 106Ag nucleus is carried out. The negative-parity doublet bands depict some unusual features that have not been observed in any isotope in the mass A =100 region. For instance, (i) the moment of inertia of the partner band is quite different from that of the yrast band, and (ii) these bands cross each other at an angular momentum of I =14 ℏ . Also, the observed significantly large but constant B (M 1 ) transitions confirm that the strong M 1 transitions are being reinforced by the contributions from collective rotation. To explain these features, a collective model has been developed whose kinetic and potential energies are extracted from the tilted-axis cranking model. Instead of the triaxial parameter γ , a second-order phase transition is found to be responsible for the spontaneous breakdown of chiral symmetry. Analytical solution of the Schrödinger equation has generated a doublet nondegenerate eigenvalue spectrum. The ensuing model results based on the two-quasiparticle configuration π g9/2⊗ν h11/2 exhibit similarities with many observed features of the negative-parity doublet bands and hence confirm their chiral character. The cranking mass parameter in kinetic energy plays an important role in diabatic crossing between these emerged chiral twin bands.

  7. Odds Ratio, Delta, ETS Classification, and Standardization Measures of DIF Magnitude for Binary Logistic Regression

    ERIC Educational Resources Information Center

    Monahan, Patrick O.; McHorney, Colleen A.; Stump, Timothy E.; Perkins, Anthony J.

    2007-01-01

    Previous methodological and applied studies that used binary logistic regression (LR) for detection of differential item functioning (DIF) in dichotomously scored items either did not report an effect size or did not employ several useful measures of DIF magnitude derived from the LR model. Equations are provided for these effect size indices.…

  8. Asymptotically Unbiased Estimation of Exposure Odds Ratios in Complete Records Logistic Regression

    PubMed Central

    Bartlett, Jonathan W.; Harel, Ofer; Carpenter, James R.

    2015-01-01

    Missing data are a commonly occurring threat to the validity and efficiency of epidemiologic studies. Perhaps the most common approach to handling missing data is to simply drop those records with 1 or more missing values, in so-called “complete records” or “complete case” analysis. In this paper, we bring together earlier-derived yet perhaps now somewhat neglected results which show that a logistic regression complete records analysis can provide asymptotically unbiased estimates of the association of an exposure of interest with an outcome, adjusted for a number of confounders, under a surprisingly wide range of missing-data assumptions. We give detailed guidance describing how the observed data can be used to judge the plausibility of these assumptions. The results mean that in large epidemiologic studies which are affected by missing data and analyzed by logistic regression, exposure associations may be estimated without bias in a number of settings where researchers might otherwise assume that bias would occur. PMID:26429998

  9. Gender ratio in a clinical population sample, age of diagnosis and duration of assessment in children and adults with autism spectrum disorder.

    PubMed

    Rutherford, Marion; McKenzie, Karen; Johnson, Tess; Catchpole, Ciara; O'Hare, Anne; McClure, Iain; Forsyth, Kirsty; McCartney, Deborah; Murray, Aja

    2016-07-01

    This article reports on gender ratio, age of diagnosis and the duration of assessment procedures in autism spectrum disorder diagnosis in a national study which included all types of clinical services for children and adults. Findings are reported from a retrospective case note analysis undertaken with a representative sample of 150 Scottish children and adults recently diagnosed with autism spectrum disorder. The study reports key findings that the gender ratio in this consecutively referred cohort is lower than anticipated in some age groups and reduces with increasing age. The gender ratio in children, together with the significant difference in the mean age of referral and diagnosis for girls compared to boys, adds evidence of delayed recognition of autism spectrum disorder in younger girls. There was no significant difference in duration of assessment for males and females suggesting that delays in diagnosis of females occur prior to referral for assessment. Implications for practice and research are considered. PMID:26825959

  10. Checking the odd Goldbach conjecture up to 10(20)

    NASA Astrophysics Data System (ADS)

    Saouter, Y.

    1998-04-01

    Vinogradov's theorem states that any sufficiently large odd integer is the sum of three prime numbers. This theorem allows us to suppose the conjecture that this is true for all odd integers. In this paper, we describe the implementation of an algorithm which allowed us to-check this conjecture up to 10(20).

  11. Could Weight-Loss Surgery Boost Odds of Preemie Birth?

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_160596.html Could Weight-Loss Surgery Boost Odds of Preemie Birth? Monitoring is ... HealthDay News) -- Mothers-to-be who've had weight-loss surgery may have increased odds for premature delivery, ...

  12. On the largest prime divisor of an odd harmonic number

    NASA Astrophysics Data System (ADS)

    Chishiki, Yusuke; Goto, Takeshi; Ohno, Yasuo

    2007-09-01

    A positive integer is called a (Ore's) harmonic number if its positive divisors have integral harmonic mean. Ore conjectured that every harmonic number greater than 1 is even. If Ore's conjecture is true, there exist no odd perfect numbers. In this paper, we prove that every odd harmonic number greater than 1 must be divisible by a prime greater than 10^5 .

  13. Depression and violence: a Swedish population study

    PubMed Central

    Fazel, Seena; Wolf, Achim; Chang, Zheng; Larsson, Henrik; Goodwin, Guy M; Lichtenstein, Paul

    2015-01-01

    Summary Background Depression increases the risk of a range of adverse outcomes including suicide, premature mortality, and self-harm, but associations with violent crime remain uncertain. We aimed to determine the risks of violent crime in patients with depression and to investigate the association between depressive symptoms and violent crime in a cohort of twins. Methods We conducted two studies. The first was a total population study in Sweden of patients with outpatient diagnoses of depressive disorders (n=47 158) between 2001 and 2009 and no lifetime inpatient episodes. Patients were age and sex matched to general population controls (n=898 454) and risk of violent crime was calculated. Additionally, we compared the odds of violent crime in unaffected half-siblings (n=15 534) and full siblings (n=33 516) of patients with the general population controls. In sensitivity analyses, we examined the contribution of substance abuse, sociodemographic factors, and previous criminality. In the second study, we studied a general population sample of twins (n=23 020) with continuous measures of depressive symptoms for risk of violent crime. Findings During a mean follow-up period of 3·2 years, 641 (3·7%) of the depressed men and 152 (0·5%) of the depressed women violently offended after diagnosis. After adjustment for sociodemographic confounders, the odds ratio of violent crime was 3·0 (95% CI 2·8–3·3) compared with the general population controls. The odds of violent crime in half-siblings (adjusted odds ratio 1·2 [95% CI 1·1–1·4]) and full siblings (1·5, 95% CI 1·3–1·6) were significantly increased, showing some familial confounding of the association between depression and violence. However, the odds increase remained significant in individuals with depression after adjustment for familial confounding, and in those without substance abuse comorbidity or a previous violent conviction (all p<0·0001). In the twin study, during the mean

  14. Coexisting Psychiatric Problems and Stressful Life Events in Adults with Symptoms of ADHD--A Large Swedish Population-Based Study of Twins

    ERIC Educational Resources Information Center

    Friedrichs, Bettina; Igl, Wilmar; Larsson, Henrik; Larsson, Jan-Olov

    2012-01-01

    Objective: To explore the associations of subtypes of adult ADHD with other psychiatric problems, stressful life events, and sex differences. Method: Odds ratios were calculated using information from 17,899 participants from a population-based survey of adult twins born in Sweden between 1959 and 1985. Results: Symptoms of attention deficit…

  15. Properties of the {pi}i{sub 13/2}x{nu}i{sub 13/2} band in odd-odd {sup 184}Au

    SciTech Connect

    Zhang, Y.H.; Fang, Y.D.; Wang, H.L.; Zhou, X.H.; Guo, W.T.; Liu, M.L.; Guo, Y.X.; Lei, X.G.; De Angelis, G.; Marginean, N.; Gadea, A.; Napoli, D.R.; Axiotis, M.; Rusu, C.; Martinez, T.; Oshima, M.; Toh, Y.

    2004-11-01

    High-spin level structure in {sup 184}Au has been reinvestigated using the multidetector array of GASP via the {sup 159}Tb({sup 29}Si,4n{gamma}){sup 184}Au reaction at a beam energy of 140 MeV. The ground-state band and the excited {pi}i{sub 13/2}x{nu}i{sub 13/2} 2-qp band have been extended up to lower and higher spin states. An upbend has been observed in the excited band at ({Dirac_h}/2{pi}){omega}{approx}0.25 MeV and is interpreted as resulting from a pair of {pi}h{sub 9/2} alignment. This low-frequency ({pi}h{sub 9/2}){sup 2} alignment is supported by the measured B(M1)/B(E2) ratios and alignment properties in neighboring odd-A nuclei. The linking transitions between the two bands and to the ground state have been established leading to a firm spin-and-parity assignment for the {pi}i{sub 13/2}x{nu}i{sub 13/2} band in {sup 184}Au. This result provides strong evidence for the low-spin signature inversion in the {pi}i{sub 13/2}x{nu}i{sub 13/2} bands of odd-odd nuclei in the A{approx}180 mass region.

  16. Nuclear spin of odd-odd α emitters based on the behavior of α -particle preformation probability

    NASA Astrophysics Data System (ADS)

    Ismail, M.; Adel, A.; Botros, M. M.

    2016-05-01

    The preformation probabilities of an α cluster inside radioactive parent nuclei for both odd-even and odd-odd nuclei are investigated. The calculations cover the isotopic chains from Ir to Ac in the mass regions 166 ≤A ≤215 and 77 ≤Z ≤89 . The calculations are employed in the framework of the density-dependent cluster model. A realistic density-dependent nucleon-nucleon (N N ) interaction with a finite-range exchange part is used to calculate the microscopic α -nucleus potential in the well-established double-folding model. The main effect of antisymmetrization under exchange of nucleons between the α and daughter nuclei has been included in the folding model through the finite-range exchange part of the N N interaction. The calculated potential is then implemented to find both the assault frequency and the penetration probability of the α particle by means of the Wentzel-Kramers-Brillouin approximation in combination with the Bohr-Sommerfeld quantization condition. The correlation of the α -particle preformation probability and the neutron and proton level sequences of the parent nucleus as obtained in our previous work is extended to odd-even and odd-odd nuclei to determine the nuclear spin and parities. Two spin coupling rules are used, namely, strong and weak rules to determine the nuclear spin for odd-odd isotopes. This work can be a useful reference for theoretical calculation of undetermined nuclear spin of odd-odd nuclei in the future.

  17. Laos: development against all the odds.

    PubMed

    1979-10-01

    Laos, with a $90 per capita income, is one of the world's poorest 15 countries. In Asia, only Bhutan is poorer. The French, when they departed, left no infrastructure for development, and the Americans, during the Vietnam war, desolated most of the area known as the Plain of Jars by bombing. At present, 750,000 persons out of a total population of 3.3 million are officially termed "displaced." Nevertheless, the Pathet Lao government, with financial aid from the World Bank and from Sweden, has initiated development policies which are beginning to have some effect. Rice production is the first priority because last year the government had to buy 120,000 tons on the open market with precious foreign currency. Irrigation schemes are being vigorously promoted, and one of them is maintained by the American Friends Service. Literacy is another priority; Lao is the official language. The absence of good roads, however, continues to hamper communications, there is a shortage of transport, no railways, and large areas of arable land still remain unusable. The country is rich in mineral resources and forest products, especially teak, but much of the present development is confined to the area immediately around the capital, Vientiane. PMID:12278251

  18. The competition between alpha decay and spontaneous fission in odd-even and odd-odd nuclei in the range 99 ≤ Z ≤ 129

    NASA Astrophysics Data System (ADS)

    Santhosh, K. P.; Priyanka, B.

    2015-08-01

    The predictions on the mode of decay of the odd-even and odd-odd isotopes of heavy and superheavy nuclei with Z = 99- 129, in the range 228 ≤ A ≤ 336, have been done within the Coulomb and proximity potential model for deformed nuclei (CPPMDN). A comparison of our calculated alpha half lives with the values computed using other theoretical models shows good agreement with each other. An extensive study on the spontaneous fission half lives of all the isotopes under study has been performed to identify the long-lived isotopes in the mass region. The study reveals that the alpha decay half lives and the mode of decay of the isotopes with Z = 109, 111, 113, 115 and 117, evaluated using our formalisms, agree well with the experimental observations. As our study on the odd-even and odd-odd isotopes of Z = 99- 129 predicts that, the isotopes 238,240-25499, 244,246-258101, 248,250,252-260,262103, 254,256,258-262,264105, 258,260,262-264,266107, 262,264,266-274109, 266,268-279111, 270-284,286113, 272-289,291115, 274-299117, 276-307119, 281-314121, 287-320,322123, 295-325125, 302-327127 and 309-329129 survive fission and have alpha decay channel as the prominent mode of decay, these nuclei could possibly be synthesized in the laboratory and this could be of great interest to the experimentalists. The behavior of these nuclei against the proton decay has also been studied to identify the probable proton emitters in this region of nuclei.

  19. Obese Mothers have Lower Odds of Experiencing Pro-breastfeeding Hospital Practices than Mothers of Normal Weight: CDC Pregnancy Risk Assessment Monitoring System (PRAMS), 2004-2008.

    PubMed

    Kair, Laura R; Colaizy, Tarah T

    2016-03-01

    Objectives This study examines the extent to which a mother's pre-pregnancy body mass index (BMI) category is associated with her exposure to pro-breastfeeding hospital practices. Methods Data from the 2004-2008 CDC PRAMS were analyzed for three states (Illinois, Maine, and Vermont) that had administered an optional survey question about hospital pro-breastfeeding practices. Results Of 19,145 mothers surveyed, 19 % were obese (pre-pregnancy BMI ≥ 30). Obese mothers had lower odds than mothers of normal weight of initiating breastfeeding [70 vs. 79 % (unweighted), p < 0.0001]. Compared with women of normal weight, obese mothers had lower odds of being exposed to pro-breastfeeding hospital practices during the birth hospitalization. Specifically, obese mothers had higher odds of using a pacifier in the hospital [odds ratio (OR) 1.31, 95 % confidence interval (CI) (1.17-1.48), p < 0.0001] and lower odds of: a staff member providing them with information about breastfeeding [OR 0.71, 95 % CI (0.57-0.89), p = 0.002], a staff member helping them breastfeed [OR 0.69, 95 % CI (0.61-0.78), p < 0.0001], breastfeeding in the first hour after delivery [OR 0.55, 95 % CI (0.49-0.62), p < 0.0001], being given a telephone number for breastfeeding help [OR 0.65, 95 % CI (0.57-0.74), p < 0.0001], rooming in [OR 0.84, 95 % CI (0.73-0.97), p = 0.02], and being instructed to breastfeed on demand [OR 0.66, 95 % CI (0.58-0.75), p < 0.0001]. Adjusting for multiple covariates, all associations except rooming in remained significant. Conclusions Obesity stigma may be a determinant of breastfeeding outcomes for obese mothers. Breastfeeding support should be improved for this at-risk population. PMID:26515471

  20. APOL1 Kidney Risk Alleles: Population Genetics and Disease Associations

    PubMed Central

    Limou, Sophie; Nelson, George W.; Kopp, Jeffrey B.; Winkler, Cheryl A.

    2014-01-01

    APOL1 kidney disease is a unique case in the field of the genetics of common disease: 2 variants (termed G1 and G2) with high population frequency have been repeatedly associated with nondiabetic CKDs, with very strong effect size (odds ratios 3–29) in populations of sub-Saharan African descent. This review provides an update on the spectrum of APOL1 kidney disease and on the worldwide distribution of these kidney risk variants. We also summarize the proper way to run a recessive analysis on joint and independent effects of APOL1 G1 and G2 kidney risk variants. PMID:25168832

  1. Veterans' Painkiller Abuse Can Raise Odds for Heroin Use

    MedlinePlus

    ... html Veterans' Painkiller Abuse Can Raise Odds for Heroin Use 3 of 4 who tried the illicit ... narcotic painkillers may be at high risk for heroin use, a new study cautions. The research included ...

  2. Two Genes May Raise Odds for Fraternal Twin Pregnancies

    MedlinePlus

    ... nih.gov/medlineplus/news/fullstory_158554.html Two Genes May Raise Odds for Fraternal Twin Pregnancies Variants ... families, researchers say they've just pinpointed two genes that seem to be associated with having such ...

  3. Two Genes May Raise Odds for Fraternal Twin Pregnancies

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_158554.html Two Genes May Raise Odds for Fraternal Twin Pregnancies Variants ... families, researchers say they've just pinpointed two genes that seem to be associated with having such ...

  4. New description of the doublet bands in doubly odd nuclei

    SciTech Connect

    Ganev, H. G.; Georgieva, A. I.; Brant, S.; Ventura, A.

    2009-04-15

    The experimentally observed {delta}I=1 doublet bands in some odd-odd nuclei are analyzed within the orthosymplectic extension of the interacting vector boson model (IVBM). A new, purely collective interpretation of these bands is given on the basis of the obtained boson-fermion dynamical symmetry of the model. It is illustrated by its application to three odd-odd nuclei from the A{approx}130 region, namely {sup 126}Pr, {sup 134}Pr, and {sup 132}La. The theoretical predictions for the energy levels of the doublet bands as well as E2 and M1 transition probabilities between the states of the yrast band in the last two nuclei are compared with experiment and the results of other theoretical approaches. The obtained results reveal the applicability of the orthosymplectic extension of the IVBM.

  5. The odd-number sequence: squares and sums

    NASA Astrophysics Data System (ADS)

    Leyendekkers, J. V.; Shannon, A. G.

    2015-11-01

    Direct study of various characteristics of integers and their interactions is readily accessible to undergraduate students. Integers obviously fall in different classes of modular rings and thus have features unique to that class which can result in a variety of formations, particularly with sums of squares. The sum of the first n odd numbers is itself the square of n within the odd number sequence, from which testing for primality within the Fibonacci sequence is investigated in this note.

  6. Characterization of isomers in the neutron-rich odd-odd nucleus {sup 156}Pm

    SciTech Connect

    Sood, P. C.; Gowrishankar, R; Sai, K. Vijay; Sainath, M.

    2011-02-15

    Critical examination of the experimental data from {sup 156}Nd and {sup 156}Pm {beta} decays and the observed location of relevant neutron and proton orbitals in the neighboring odd-A isotones and isotopes, taken together with the low-lying two-quasiparticle (2qp) structures expected in {sup 156}Pm from the rotor-particle model, lead to the conclusion that a consistent description of all the available data is achieved with the I{sup {pi}}=4{sup +} spin-parity assignment to the 26.7s {sup 156}Pm ground state (g.s.) and assignment of I{sup {pi}}=1{sup +} to its 150.3-keV isomer with the 2qp configuration 4{sub g.s.}{sup +}{l_brace}p{sub o}:5/2[532{up_arrow}]{+-}n{sub o}:3/2[521{up_arrow}]{r_brace}1{sub 150}{sup +}. In the process, a two-neutron configuration is also suggested for the 1509-keV 4{sup +} level in the daughter nucleus {sup 156}Sm. The present analysis reiterates the important question of whether the {beta}-decay log ft value, by itself, can be employed to deduce the relative parity of the {beta}-connected states.

  7. Double Brillouin frequency shift through circulation of odd-order Stokes signal.

    PubMed

    Shee, Yu Gang; Al-Mansoori, Mohammed Hayder; Ismail, Alyani; Hitam, Salasiah; Mahdi, Mohd Adzir

    2010-07-10

    We demonstrate a simple configuration for generating a double Brillouin frequency shift through the circulation of an odd-order Brillouin Stokes signal. It is operated based on cascaded Brillouin scattering in single-mode optical fibers that behave as the Brillouin gain media. A four-port circulator is incorporated into the setup to circulate the odd-order Brillouin Stokes signal in the fiber. It thus initiates a higher order Brillouin Stokes signal, which is double Brillouin frequency downshifted from the input signal. For the 5 km long fiber, the Brillouin pump power at 23 mW gives a clean output spectrum with 30 dB sideband suppression ratio. The output signal is 0.174 nm or approximately 21.7 GHz downshifted from the input signal. PMID:20648173

  8. Some features of the ecology of fleas inhabiting the nests of the suslik (Citellus citellus (L.)). I: Population dynamics, sex ratio, feeding, reproduction.

    PubMed

    Ryba, J; Rödl, P; Bartos, L; Daniel, M; Cerný, V

    1986-01-01

    While studying the suslik fleas in artificial nests planted in free nature, significant changes in the population dynamics of N. setosa, C. simplex and C. orientalis (from the spring build up to the autumnal peak and the decrease of flea number until the next spring) were noted. The predominance of females in the spring period was recorded in N. setosa. Significant seasonal changes in the number of engorged females of N. setosa and C. simplex and of C. orientalis males (the increase of engorged specimens in the spring and summer) were demonstrated. A significant predominance of females with mature eggs in the spring and summer and their negligible number in the autumn were found in N. setosa and C. simplex. PMID:3758870

  9. Influence of secondary decay on odd-even staggering of fragment cross sections

    NASA Astrophysics Data System (ADS)

    Winkelbauer, J. R.; Souza, S. R.; Tsang, M. B.

    2013-10-01

    Odd-even staggering (OES) appears in many areas of nuclear physics and is generally associated with the pairing term in the nuclear binding energy. To explore this effect, we use the improved statistical multifragmentation model to populate an ensemble of hot primary fragments, which are then de-excited using the Weisskopf-Ewing statistical emission formalism. The yields are then compared to experimental data. Our results show that, before secondary decay, OES appears only in the yields of even mass fragments and not in the yields of odd mass fragments. De-excitation of the hot fragments must be taken into account to describe the data, suggesting that the OES in fragment yields is a useful criterion for validating or adjusting theoretical de-excitation models.

  10. Excited states of deformable odd {sup 157,159}Tb nuclei: Nonconservation of the angular momentum of external nucleon

    SciTech Connect

    Sharipov, Sh.; Ermamatov, M. J.

    2009-01-15

    The previously developed rotationally single-particle and vibrational model of the triaxial deformable odd nuclei is extended to the case where the total angular momentum of an external nucleon is not conserved. The calculated ratios of the excitation energies of the {sup 157,159}Tb nuclei are compared with the existing experimental data. The ratios of E2-transition probabilities and those of quadrupole moments of the above nuclei are calculated using parameters determined from the spectra of these nuclei.

  11. How Methodology Decisions Affect the Variability of Schools Identified as Beating the Odds. REL 2015-071

    ERIC Educational Resources Information Center

    Abe, Yasuyo; Weinstock, Phyllis; Chan, Vincent; Meyers, Coby; Gerdeman, R. Dean; Brandt, W. Christopher

    2015-01-01

    Schools that show better academic performance than would be expected given characteristics of the school and student populations are often described as "beating the odds" (BTO). State and local education agencies often attempt to identify such schools as a means of identifying strategies or practices that might be contributing to the…

  12. How Methodology Decisions Affect the Variability of Schools Identified as Beating the Odds. REL 2015-071.rev

    ERIC Educational Resources Information Center

    Abe, Yasuyo; Weinstock, Phyllis; Chan, Vincent; Meyers, Coby; Gerdeman, R. Dean; Brandt, W. Christopher

    2015-01-01

    A number of states and school districts have identified schools that perform better than expected, given the populations they serve, in order to recognize school performance or to learn from local school practices and policies. These schools have been labeled "beating the odds," "high-performing/high-poverty,"…

  13. Efficiency and bacterial populations related to pollutant removal in an upflow microaerobic sludge reactor treating manure-free piggery wastewater with low COD/TN ratio.

    PubMed

    Meng, Jia; Li, Jiuling; Li, Jianzheng; Sun, Kai; Antwi, Philip; Deng, Kaiwen; Wang, Cheng; Buelna, Gerardo

    2016-02-01

    A novel upflow microaerobic sludge reactor (UMSR) had proved excellent in nitrogen removal from manure-free piggery wastewater characterized by high concentration of ammonium (NH4(+)-N) and low chemical oxygen demand (COD) to total nitrogen (TN) ratio, but the biological mechanism in the UMSR was still indeterminate. With a constant nitrogen loading rate of 1.10kg/(m(3)d) at hydraulic retention time 8h, the UMSR was kept performing for 67days in the present research and the average load removal of COD, NH4(+)-N and TN was as high as 0.72, 0.76 and 0.94kg/(m(3)d), respectively. Compared with the inoculated sludge, the acclimated sludge was richer in genera responsible for the biological removal of carbon, nitrogen and phosphorus. Ammonium oxidation bacteria, heterotrophic denitrifiers, autotrophic denitrifiers and phosphate accumulating organisms coexisted perfectly in the microaerobic system, and their synergistic action made the UMSR perform well in COD, NH4(+)-N, TN and phosphate removal. PMID:26649897

  14. Hazard Ratio and Repeat Injury for Dementia in Patients With and Without a History of Traumatic Brain Injury: A Population-Based Secondary Data Analysis in Taiwan.

    PubMed

    Chu, Shu-Fen; Chiu, Wen-Ta; Lin, Hui-Wen; Chiang, Yung-Hsiao; Liou, Tsan-Hon

    2016-09-01

    The impact of traumatic brain injury (TBI) on the pathogenic hazard ratio (HR) for dementia patients is still controversial. Some studies have supported the association between TBI and dementia, especially for Alzheimer's disease, and our study determined that the HR of dementia patients with and without a history of TBI or repeated TBI (RTBI). We determined the HR for dementia patients with a diagnosis of TBI (n = 12931) and a comparative cohort with age- and gender-matched controls (n = 51724) during 2004-2005, using Taiwan's National Health Insurance Research Database. The adjusted HR (HR = 3.21) for dementia patients with TBI showed that they were more likely to develop dementia than the comparison cohort. The HR for dementia patients with RTBI was increased to 3.62. The results of this large-scale study suggested that TBI increases dementia risk. Future studies using animal models and epidemiological databases could elucidate medical and biological mechanisms linking TBI and the development of dementia. PMID:27614252

  15. Strong male-biased operational sex ratio in a breeding population of loggerhead turtles (Caretta caretta) inferred by paternal genotype reconstruction analysis

    PubMed Central

    Lasala, Jacob A; Harrison, J Scott; Williams, Kris L; Rostal, David C

    2013-01-01

    Characterization of a species mating systems is fundamental for understanding the natural history and evolution of that species. Polyandry can result in the multiple paternity of progeny arrays. The only previous study of the loggerhead turtle (Caretta caretta) in the USA showed that within the large peninsular Florida subpopulation, multiple paternity occurs in approximately 30% of clutches. Our study tested clutches from the smaller northern subpopulation for the presence of multiple paternal contributions. We examined mothers and up to 20 offspring from 19.5% of clutches laid across three nesting seasons (2008–2010) on the small nesting beach on Wassaw Island, Georgia, USA. We found that 75% of clutches sampled had multiple fathers with an average of 2.65 fathers per nest (1–7 fathers found). The average number of fathers per clutch varied among years and increased with female size. There was no relationship between number of fathers and hatching success. Finally, we found 195 individual paternal genotypes and determined that each male contributed to no more than a single clutch over the 3-year sampling period. Together these results suggest that the operational sex ratio is male-biased at this site. PMID:24363901

  16. Examining the reproducibility of stable isotope ratios in the marine bivalve, Astarte borealis, from populations in the White Sea, Russia: implications for biological consequences of climate change

    NASA Astrophysics Data System (ADS)

    McNabb, Justin; Surge, Donna

    2015-04-01

    Shells of the marine bivalve, Astarte, are uniquely suited to investigate links between environmental/climate change and biological consequences because of their change in size and biogeographic distribution through time. For example, are there corresponding changes in lifespan and biogeographic distribution depending on warm vs. cold climate states? Does warm vs. cold climate state result in longer or shorter lifespans? Early studies of Astarte have documented a decrease in shell size through geologic time. Modern specimens are much smaller than those from the mid Pliocene at similar latitudes. Astarte had a wide latitudinal and cosmopolitan distribution in the western North Atlantic during the Oligocene to Pliocene. During the early Pleistocene, most of the warm-water species became extinct, and today, their biogeographic distribution is mostly restricted to the northern Pacific, Atlantic, and Arctic Oceans. To answer questions linking biological consequences and climate change, we must first decipher ontogenetic changes in shell growth of modern specimens. Preliminary data using isotope sclerochronology identified slowed shell growth from late summer to winter in modern specimens from the White Sea, Russia, possibly triggered by increasing freshwater input and decreasing temperatures. Here, we present new data examining the reproducibility of isotopic time series and season of slowed growth among modern individuals collected at the same time from the same population.

  17. Parent-adolescent conflict in teenagers with ADHD and ODD.

    PubMed

    Edwards, G; Barkley, R A; Laneri, M; Fletcher, K; Metevia, L

    2001-12-01

    Eighty-seven male teens (ages 12-18 years) with ADHD/ODD and their parents were compared to 32 male teens and their parents in a community control (CC) group on mother, father, and teen ratings of parent-teen conflict and communication quality, parental self-reports of psychological adjustment, and direct observations of parent-teen problem-solving interactions during a neutral and conflict discussion. Parents and teens in the ADHD/ODD group rated themselves as having significantly more issues involving parent-teen conflict, more anger during these conflict discussions, and more negative communication generally, and used more aggressive conflict tactics with each other than did parents and teens in the CC group. During a neutral discussion, only the ADHD/ODD teens demonstrated more negative behavior. During the conflict discussion, however, the mothers, fathers, and teens in the ADHD/ODD group displayed more negative behavior, and the mothers and teens showed less positive behavior than did participants in the CC group. Differences in conflicts related to sex of parent were evident on only a few measures. Both mother and father self-rated hostility contributed to the level of mother-teen conflict whereas father self-rated hostility and anxiety contributed to father-teen conflict beyond the contribution made by level of teen ODD and ADHD symptoms. Results replicated past studies of mother-child interactions in ADHD/ODD children, extended these results to teens with these disorders, showed that greater conflict also occurs in father-teen interactions, and found that degree of parental hostility, but not ADHD symptoms, further contributed to levels of parent-teen conflict beyond the contribution made by severity of teen ADHD and ODD symptoms. PMID:11761288

  18. Dipole strength distributions of the stable odd-mass N=82 isotones {sup 139}La and {sup 141}Pr

    SciTech Connect

    Scheck, M.; Brentano, P. von; Fransen, C.; Linnemann, A.; Muecher, D.; Pietralla, N.; Scholl, C.; Werner, V.; Kneissl, U.; Kohstall, C.; Pitz, H. H.; Stedile, F.; Walter, S.; Yates, S. W.

    2007-04-15

    The low-lying dipole strength distributions of the odd-mass isotopes {sup 139}La and {sup 141}Pr were studied in nuclear resonance fluorescence experiments using bremsstrahlung beams. Excited states were observed at excitation energies up to 4 MeV. Spectroscopic information was obtained on excitation energies, decay widths, decay branching ratios, and transition probabilities. The states belonging to the [[2{sup +}(multiply-in-circle sign)3{sup -}](multiply-in-circle sign)particle/hole] coupling were a special focus, and the results are compared with other stable odd-mass nuclei at or near the N=82 shell closure.

  19. Multicomponent fluids of hard hyperspheres in odd dimensions

    NASA Astrophysics Data System (ADS)

    Rohrmann, René D.; Santos, Andrés

    2011-01-01

    Mixtures of hard hyperspheres in odd-space dimensionalities are studied with an analytical approximation method. This technique is based on the so-called rational function approximation and provides a procedure for evaluating equations of state, structure factors, radial distribution functions, and direct correlation functions of additive mixtures of hard hyperspheres with any number of components and in arbitrary odd-dimension space. The method gives the exact solution of the Ornstein-Zernike equation coupled with the Percus-Yevick closure, thus, extending the solution for hard-sphere mixtures [J. L. Lebowitz, Phys. Rev.PHRVAO0031-899X10.1103/PhysRev.133.A895 133, A895 (1964)] to arbitrary odd dimensions. Explicit evaluations for binary mixtures in five dimensions are performed. The results are compared with computer simulations, and a good agreement is found.

  20. Effect of time-odd fields on odd-even mass differences of semi-magic nuclei

    NASA Astrophysics Data System (ADS)

    Yu, Kun; Zhou, XianRong; Cui, JiWei; Sagawa, H.

    2016-05-01

    The effect of time-odd fields of Skyrme interaction on neutron odd-even mass differences is studied in the framework of axially deformed Skyrme Hartree-Fock (DSHF)+BCS model. To this end, we take into account both the time-even and time-odd fields to calculate the one-neutron and two-neutron separation energies and pairing gaps of semi-magic Ca, Ni, and Sn isotopic chains. In the calculations, a surface-type pairing interaction (IS pairing) and an isospin dependent contact pairing interaction (IS+IV pairing) are adopted on top of Skyrme interactions SLy4, SLy6 and SkM*, respectively. We find that the time-odd fields have in general small effects on pairing gaps, but achieve better agreement with experimental data using SLy4 and Sly6 interactions, respectively. It is also shown that the calculations with IS+IV pairing reproduce the one-neutron separation energies of Sn isotopes better than those with the IS pairing interaction when the contributions of the time-odd fields are included.

  1. Glycemic Change After Pancreaticoduodenectomy: A Population-Based Study.

    PubMed

    Wu, Jin-Ming; Ho, Te-Wei; Kuo, Ting-Chun; Yang, Ching-Yao; Lai, Hong-Shiee; Chiang, Pin-Yi; Hsieh, Su-Hua; Lai, Feipei; Tien, Yu-Wen

    2015-07-01

    The purpose of this population-based study was to determine the change of glucose metabolism in patients undergoing pancreaticoduodenectomy (PD).We conducted a nationwide cohort study using data from Taiwan's National Health Insurance Research Database collected between 2000 and 2010. Our sample included 861 subjects with type 2 diabetes mellitus (DM) and 3914 subjects without DM.Of 861 subjects with type 2 diabetes, 174 patients (20.2%) experienced resolution of their diabetes after PD, including patients with pancreatic ductal adenocarcinoma (PDAC) (20.5%), and non-PDAC (20.1%). Using a multiple logistic regression model, we found that subjects with comorbid chronic pancreatitis (odds ratio, 0.356; 95% CI, 0.167-0.759; P = 0.007) and use of insulin (odds ratio, 0.265; 95% CI, 0.171-0.412; P < 0.001) had significantly lower rates of resolution of diabetes. In the 3914 subjects without diabetes, the only statistically significant comorbidity contributing to pancreatogenic diabetes was chronic pancreatitis (odds ratio, 1.446; 95% CI, 1.146-1.823; P = 0.002).Subjects with comorbid chronic pancreatitis and use of insulin had lower rates of resolution of DM after PD. In subjects without diabetes, chronic pancreatitis contributed significantly to the development of pancreatogenic DM. PMID:26166104

  2. Extremal charged rotating dilaton black holes in odd dimensions

    NASA Astrophysics Data System (ADS)

    Allahverdizadeh, Masoud; Kunz, Jutta; Navarro-Lérida, Francisco

    2010-09-01

    Employing higher-order perturbation theory, we find a new class of charged rotating black hole solutions of Einstein-Maxwell-dilaton theory with general dilaton coupling constant. Starting from the Myers-Perry solutions, we use the electric charge as the perturbative parameter, and focus on extremal black holes with equal-magnitude angular momenta in odd dimensions. We perform the perturbations up to 4th order for black holes in 5 dimensions and up to 3rd order in higher odd dimensions. We calculate the physical properties of these black holes and study their dependence on the charge and the dilaton coupling constant.

  3. Search for a very light CP-odd neutral Higgs boson of the MSSM

    NASA Astrophysics Data System (ADS)

    Buskulic, D.; Decamp, D.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Mours, B.; Alemany, R.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Gaitan, V.; Garrido, Ll.; Pacheco, A.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Maggi, M.; Natali, S.; Nuzzo, S.; Quattromini, M.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Gao, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Lou, J.; Qiao, C.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhao, W.; Atwood, W. B.; Bauerdick, L. A. T.; Blucher, E.; Bonvicini, G.; Bossi, F.; Boudreau, J.; Burnett, T. H.; Drevermann, H.; Forty, R. W.; Hagelberg, R.; Harvey, J.; Haywood, S.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lançon, E.; Lehraus, I.; Lohse, T.; Lusiani, A.; Martinez, M.; Mato, P.; Mattison, T.; Meinhard, H.; Menary, S.; Meyer, T.; Minten, A.; Miquel, R.; Moser, H.-G.; Nash, J.; Palazzi, P.; Perlas, J. A.; Ranjard, F.; Redlinger, G.; Rolandi, L.; Roth, A.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Wachsmuth, H.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Badaud, F.; Bardadin-Otwinowska, M.; Bencheikh, A. M.; El Fellous, R.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Pietrzyk, B.; Proriol, J.; Prulhière, F.; Stimpfl, G.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Møllerud, R.; Nilsson, B. S.; Efthymiopoulos, I.; Kyriakis, A.; Simopoulou, E.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Fouque, G.; Gamess, A.; Orteu, S.; Rosowsky, A.; Rougé, A.; Rumpf, M.; Tanaka, R.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Moneta, L.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Ikeda, M.; Lannutti, J.; Levinthal, D.; Mermikides, M.; Sawyer, L.; Wasserbaech, S.; Antonelli, A.; Baldini, R.; Bencivenni, G.; Bologna, G.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; D'Ettorre-Piazzoli, B.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Picchi, P.; Altoon, B.; Boyle, O.; Colrain, P.; Ten Have, I.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Scarr, J. M.; Smith, K.; Thompson, A. S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geiges, R.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Belk, A. T.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Dugeay, S.; Greene, A. M.; Hassard, J. F.; Lieske, N. M.; Patton, S. J.; Payne, D. G.; Phillips, M. J.; Sedgbeer, J. K.; Tomalin, I. R.; Wright, A. G.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttall, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Barczewski, T.; Kleinknecht, K.; Raab, J.; Renk, B.; Roehn, S.; Sander, H.-G.; Schmidt, H.; Steeg, F.; Walther, S. M.; Wolf, B.; Aubert, J.-J.; Benchouk, C.; Bernard, V.; Bonissent, A.; Carr, J.; Coyle, P.; Drinkard, J.; Etienne, F.; Papalexiou, S.; Payre, P.; Qian, Z.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Bauer, C.; Blum, W.; Brown, D.; Cowan, G.; Dehning, B.; Dietl, H.; Dydak, F.; Fernandez-Bosman, M.; Frank, M.; Halley, A. W.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Richter, R.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Stiegler, U.; St. Denis, R.; Takashima, M.; Thomas, J.; Wolf, G.; Bertin, V.; Boucrot, J.; Callot, O.; Chen, X.; Cordier, A.; Davier, M.; Grivaz, J.-F.; Heusse, Ph.; Janot, P.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Zhang, Z.; Zomer, F.; Abbaneo, D.; Amendolia, S. R.; Bagliesi, G.; Batignani, G.; Bosisio, L.; Bottigli, U.; Bradaschia, C.; Carpinelli, M.; Ciocci, M. A.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Focardi, E.; Forti, F.; Giassi, A.; Giorgi, M. A.; Ligabue, F.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Carter, J. M.; Green, M. G.; March, P. V.; Mir, Ll. M.; Medcalf, T.; Quazi, I. S.; Strong, J. A.; West, L. R.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Edwards, M.; Fisher, S. M.; Jones, T. J.; Norton, P. R.; Salmon, D. P.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Kozanecki, W.; Lemaire, M. C.; Locci, E.; Loucatos, S.; Monnier, E.; Perez, P.; Perrier, F.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.; Johnson, R. P.; Litke, A. M.; Taylor, G.; Wear, J.; Ashman, J. G.; Babbage, W.; Booth, C. N.; Buttar, C.; Carney, R. E.; Cartwright, S.; Combley, F.; Hatfield, F.; Reeves, P.; Thompson, L. F.; Barberio, E.; Brandt, S.; Grupen, C.; Mirabito, L.; Schäfer, U.; Ganis, G.; Giannini, G.; Gobbo, B.; Ragusa, F.; Bellantoni, L.; Cinabro, D.; Conway, J. S.; Cowen, D. F.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; Grahl, J.; Harton, J. L.; Jared, R. C.; Leclaire, B. W.; Lishka, C.; Pan, Y. B.; Pater, J. R.; Pusztaszeri, J.-F.; Saadi, Y.; Sharma, V.; Schmitt, M.; Shi, Z. H.; Walsh, A. M.; Weber, F. V.; Whitney, M. H.; Sau Lan Wu; Wu, X.; Zobernig, G.; Aleph Collaboration

    1992-07-01

    The reactions e+e- → hZ∗ande+e- → hA have been used to search for the neutral Higgs bosons h and A of the MSSM in the case where the CP-odd A is lighter than 2 mμ, taking into account the large h → AA decay branching ratio. No signal was found in the data sample collected until the end of 1991 by the ALEPH experiment at LEP. For tan β ⩾, mA < 2 mμ is excluded at 95% CL for any mh.

  4. Entrance-channel effects in odd-Z tranactinide compound nucleus reactions

    SciTech Connect

    Nelson, S.L.; Gregorich, K.E.; Dragojevic, I.; Dullmann, Ch.E.; Eichler, R.; Folden III, C.M.; Garcia, M.A.; Gates, J.M.; Stavsetra, L.; Sudowe, R.; Nitsche, H.

    2007-09-01

    Swiatecki, Siwek-Wilczynska, and Wilczynski's 'Fusion By Diffusion' description [1] of transactinide (TAN) compound nucleus (CN) formation utilizes a three-step model. The first step is the 'sticking', or capture, which can be calculated relatively accurately. The second step is the probability for the formation of a CN by 'diffusion' analogous to that of Brownian motion. Lastly, there exists the probability of the CN 'surviving' deexcitation by neutron emission, which competes with fission and other de-excitation modes. This model predicts and reproduces cross sections typically within a factor of two. Producing the same CN with different projectile-target pairs is a very sensitive way to test entrance channel effects on heavy element production cross sections. If the same CN is produced at or near the same excitation energy the survival portion of the theory is nearly identical for the two reactions. This method can be used as a critical test of the novel 'diffusion' portion of the model. The reactions producing odd-Z TAN CN such as Db, Bh, Mt, and Rg (Z = 105, 107, 109, and 111, respectively) were first studied using even-Z projectiles on {sup 209}Bi targets (as opposed to odd-Z projectiles on {sup 208}Pb targets) because lower effective fissility [2] was expected to lead to larger cross sections. Many odd-Z projectile reactions producing odd-Z CN had not been studied in-depth until very recently. We have completed studies of these reaction pairs with the 88-Inch Cyclotron and the Berkeley Gas-Filled Separator (BGS) at the Lawrence Berkeley National Laboratory (LBNL), see Figure 1. Cross section ratios for several pairs of reactions will be presented and compared with theory.

  5. Dietary Pattern and Risk of Hodgkin Lymphoma in a Population-Based Case-Control Study

    PubMed Central

    Epstein, Mara M.; Chang, Ellen T.; Zhang, Yawei; Fung, Teresa T.; Batista, Julie L.; Ambinder, Richard F.; Zheng, Tongzhang; Mueller, Nancy E.; Birmann, Brenda M.

    2015-01-01

    Classic Hodgkin lymphoma (cHL) has few known modifiable risk factors, and the relationship between diet and cHL risk is unclear. We performed the first investigation of an association between dietary pattern and cHL risk in 435 cHL cases and 563 population-based controls from Massachusetts and Connecticut (1997–2000) who completed baseline diet questionnaires. We identified 4 major dietary patterns (“vegetable,” “high meat,” “fruit/low-fat dairy,” “desserts/sweets”) using principal components analysis. We computed multivariable odds ratios and 95% confidence intervals for associations of dietary pattern score (quartiles) with younger-adult (age <50 years), older-adult (age ≥50 years), and overall cHL risk. Secondary analyses examined associations by histological subtype and tumor Epstein-Barr virus (EBV) status. A diet high in desserts/sweets was associated with younger-adult (odds ratio(quartile 4 vs. quartile 1) = 1.60, 95% confidence interval: 1.05, 2.45; Ptrend = 0.008) and EBV-negative, younger-adult (odds ratio = 2.11, 95% confidence interval: 1.31, 3.41; Ptrend = 0.007) cHL risk. A high meat diet was associated with older-adult (odds ratio = 3.34, 95% confidence interval: 1.02, 10.91; Ptrend = 0.04) and EBV-negative, older-adult (odds ratio = 4.64, 95% confidence interval: 1.03, 20.86; Ptrend = 0.04) cHL risk. Other dietary patterns were not clearly associated with cHL. We report the first evidence for a role of dietary pattern in cHL etiology. Diets featuring high intake of meat or desserts and sweets may increase cHL risk. PMID:26182945

  6. New spin assignments in the odd-odd N=Z nucleus Sc42 and the breaking of the Ca40 core

    NASA Astrophysics Data System (ADS)

    Scholl, C.; Petkov, P.; Werner, V.; Linnemann, A.; Adachi, T.; Dewald, A.; Fitzler, A.; Fransen, C.; Fujita, Y.; Jolie, J.; Langanke, K.; Lisetskiy, A. F.; Martinez-Pinedo, G.; Mücher, D.; Orce, J. N.; Pietralla, N.; Warr, N.; Zell, K. O.; Brentano, P. Von

    2007-06-01

    Using the Ca40(He3,p) reaction at E3He=9 MeV and the multidetector array HORUS, angular correlations of coincident pairs of γ transitions in the odd-odd N=Z nucleus Sc42 have been measured at the FN tandem Van de Graaff accelerator of the University of Cologne. The analysis of the data allowed nine new spin assignments and the determination of a series of new multipole mixing ratios. In particular, the spin and parity of the 5+ and 7+ levels belonging to the lowest T=0πf7/2νf7/2 multiplet have been determined and the (6+) level from the T=1 multiplet has been tentatively assigned. In this way, all T=1 states up to an excitation energy of 3.2 MeV now have known spins as well as the lowest T=0 quadruplet (Jπ=1+,3+,5+,7+) and many other T=0 states of unknown structure. The comparison with shell-model calculations reveals that a breaking of the Ca40 core has to be invoked to describe the level structure of Sc42.

  7. New spin assignments in the odd-odd N=Z nucleus {sup 42}Sc and the breaking of the {sup 40}Ca core

    SciTech Connect

    Scholl, C.; Linnemann, A.; Dewald, A.; Fitzler, A.; Fransen, C.; Jolie, J.; Muecher, D.; Warr, N.; Zell, K. O.; Brentano, P. von; Petkov, P.; Werner, V.; Adachi, T.; Fujita, Y.; Langanke, K.; Martinez-Pinedo, G.; Lisetskiy, A. F.; Orce, J. N.; Pietralla, N.

    2007-06-15

    Using the {sup 40}Ca({sup 3}He,p) reaction at E{sub {sup 3}He}=9 MeV and the multidetector array HORUS, angular correlations of coincident pairs of {gamma} transitions in the odd-odd N=Z nucleus {sup 42}Sc have been measured at the FN tandem Van de Graaff accelerator of the University of Cologne. The analysis of the data allowed nine new spin assignments and the determination of a series of new multipole mixing ratios. In particular, the spin and parity of the 5{sup +} and 7{sup +} levels belonging to the lowest T=0{pi}f{sub 7/2}{nu}f{sub 7/2} multiplet have been determined and the (6{sup +}) level from the T=1 multiplet has been tentatively assigned. In this way, all T=1 states up to an excitation energy of 3.2 MeV now have known spins as well as the lowest T=0 quadruplet (J{sup {pi}}=1{sup +},3{sup +},5{sup +},7{sup +}) and many other T=0 states of unknown structure. The comparison with shell-model calculations reveals that a breaking of the {sup 40}Ca core has to be invoked to describe the level structure of {sup 42}Sc.

  8. Common Variants in the TBX5 Gene Associated with Atrial Fibrillation in a Chinese Han Population

    PubMed Central

    Li, Huihua; Yin, Xiaomeng; Dong, Yingxue; Yang, Yanzong; Xia, Yunlong

    2016-01-01

    Background PR interval variations have recently been associated with an increased risk of long-term atrial fibrillation (AF), heart block and all-cause mortality. Genome-wide association studies have linked the PR interval with several common variants in the TBX5 gene. Several variants in the TBX5 gene, including rs7312625 and rs883079, have been associated with AF. The purpose of this study was to determine the association of single-nucleotide polymorphisms (SNPs) in the TBX5 gene, rs7312625 and rs883079, with AF in Chinese Han patients. Methodology/Principal Findings In this case-control association study, large cohorts of AF patients (n = 1132) and controls (n = 1206) were recruited from different hospitals. The genotyping was performed using a Rotor-Gene TM 6000 high-resolution melt system. Rs7312625, rs3825214 and rs883079 were analyzed. We found that SNP 3825214 was significantly associated with AF (P-obs = 0.002, odds ratio [OR] = 0.82), and lone AF (P-obs = 6.77x10-5, odds ratio [OR] = 0.71). SNP rs7312625 was significantly associated with lone AF (P-obs = 0.015, odds ratio [OR] = 1.27), although its association with AF was not significant. No significant association of SNP rs883079 with AF or lone AF was observed. Thus, we analyzed the interaction among these three loci. We demonstrated significant interaction among rs3825214, rs7312625 and rs883079. Four-locus risk alleles showed the highest odds ratio in combined rs3825214 and rs7312625 (P-obs<0.0001, odds ratio [OR] = 2.21). Six-locus risk alleles showed the highest odds ratio in combined rs3825214, rs7312625 and rs 883079(P-obs<0.0001, odds ratio [OR] = 2.35). Significance was established with the trend test (P<0.0001). Conclusions For the first time, we report the strong association of SNP rs3825214 in the TBX5 gene with AF and lone AF in a Chinese Han population. Rs7312625 was significantly associated with lone AF, and snp-snp interaction increased the risk of atrial fibrillation. Our data might

  9. The Antarctic ozone minimum - Relationship to odd nitrogen, odd chlorine, the final warming, and the 11-year solar cycle

    NASA Technical Reports Server (NTRS)

    Callis, L. B.; Natarajan, M.

    1986-01-01

    Photochemical calculations along 'diabatic trajectories' in the meridional phase are used to search for the cause of the dramatic springtime minimum in Antarctic column ozone. The results indicate that the minimum is principally due to catalytic destruction of ozone by high levels of total odd nitrogen. Calculations suggest that these levels of odd nitrogen are transported within the polar vortex and during the polar night from the middle to upper stratosphere and lower mesosphere to the lower stratosphere. The possibility that these levels are related to the 11-year solar cycle and are increased by enhanced formation in the thermosphere and mesosphere during solar maximum conditions is discussed.

  10. Are the Odds Against the Origin of Life Too Great?

    ERIC Educational Resources Information Center

    Carrier, Richard

    2000-01-01

    Statistics are offered to "prove" odds against the origin of life. Presents a summary analysis of all known examples to be used to check these claims whenever they are brought up in conversations, debates, books, or articles. Addresses scientific work misused by anti-evolutionists and the pseudoscientific assertions of the anti-evolutionists…