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Sample records for explain selective differences

  1. Does sexual selection explain human sex differences in aggression?

    Science.gov (United States)

    Archer, John

    2009-08-01

    I argue that the magnitude and nature of sex differences in aggression, their development, causation, and variability, can be better explained by sexual selection than by the alternative biosocial version of social role theory. Thus, sex differences in physical aggression increase with the degree of risk, occur early in life, peak in young adulthood, and are likely to be mediated by greater male impulsiveness, and greater female fear of physical danger. Male variability in physical aggression is consistent with an alternative life history perspective, and context-dependent variability with responses to reproductive competition, although some variability follows the internal and external influences of social roles. Other sex differences, in variance in reproductive output, threat displays, size and strength, maturation rates, and mortality and conception rates, all indicate that male aggression is part of a sexually selected adaptive complex. Physical aggression between partners can be explained using different evolutionary principles, arising from the conflicts of interest between males and females entering a reproductive alliance, combined with variability following differences in societal gender roles. In this case, social roles are particularly important since they enable both the relatively equality in physical aggression between partners from Western nations, and the considerable cross-national variability, to be explained.

  2. Sexually Selected Sex Differences in Competitiveness Explain Sex Differences in Changes in Drinking Game Participation

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    Liana S. E. Hone

    2015-04-01

    Full Text Available Drinking games are a risk factor for behavioral and health problems among university students. Previous cross-sectional research by Hone, Carter, and McCullough (2013 replicated well-established sex differences in drinking game behaviors (i.e., that men are more active drinking game participants than are women and university drinking problems more generally. Hone et al. (2013 also found that these male-specific behavioral patterns are attributable in part to the fact that men's generally unrestricted sexual strategies, plus their social competitiveness, motivate them to participate in drinking games to display their fortitude and compete with same-sex rivals. Here, the authors conducted a study to evaluate with greater causal rigor whether sex differences in sexual restrictedness and social competitiveness—and sex differences in motivations for participating in drinking games in particular—are partially responsible for the sex differences in university students' drinking game behaviors and drinking problems. Sex differences in changes in frequency of drinking game participation were partially mediated by competitive motivations for participating in drinking games and by the effects of social competitiveness on competitive drinking game motivation. These findings lend additional support to the proposition that participation in drinking games is motivated in part by their suitability as a venue for sexual competition in university students' day-to-day lives.

  3. THE ROLE OF AGENCY COSTS IN EXPLAINING FINANCIAL PERFORMANCE DIFFERENCES: AN EMPIRICAL ANALYSIS ON SELECTED PUBLIC FIRMS IN BRIC COUNTRIES

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    A. Osman GÜRBÜZ

    2016-01-01

    Full Text Available The consequences of the recent corporate scandals have directed the attention of corporations towards the opportunistic behaviors of managers; thus, evaluation of agency costs encountered within the firm. The divergence of interest between the managers and shareholders has a potential to con- stitute a threat to the firms’ financial performance. Due to the rising importance of the topic for both academic literature and practical grounds, this study attempts to evaluate the link between agency costs of equity and financial performance of selected public firms operating in BRIC countries be- tween the years 2003 and 2014, inclusive. Three measures have been utilized to proxy for agency costs of equity; namely, asset utilization ratio, operating expense ratio, and the ratio of free cash flows to total assets. An additional interaction variable is also generated to take into account the existence of investment opportunities when free cash flows are abundant. The findings based on panel data analysis are considered to provide useful insight upon an additional explanation to the presence of financial performance differences among the firms other than simply firm-specific attributes and emphasize the importance of finding mechanisms for alleviating agency costs to attain the overall goal of share- holder wealth maximization.

  4. Can marital selection explain the differences in health between married and divorced people? From a longitudinal study of a British birth cohort.

    Science.gov (United States)

    Cheung, Y B

    1998-03-01

    In view of the rising divorce rates, the impact of divorce on health has an increasing importance in public health. The differentials in health between the married and the divorced may be explained by 'marital selection' and 'marital protection'. Using longitudinal data from a study of the 1958 British birth cohort, factors that select people into divorce were identified from the areas of socio-economic status, health, and attractiveness, which included physical attractiveness, health-related behaviour and temperament. Evidence for both positive and adverse selection is found. The different sets of selection factors for females and males appear to be in line with gender role expectations. The health differentials between married and divorced men were weak and can be explained away by the selection factors. Having controlled for the selection effects, there were still significant associations between divorce and physical and psychological health in women. Though these unexplained differentials cannot be definitely interpreted as the consequences of marital dissolution, this interpretation remains plausible.

  5. Explaining dog wolf differences in utilizing human pointing gestures: selection for synergistic shifts in the development of some social skills.

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    Márta Gácsi

    2009-08-01

    Full Text Available The comparison of human related communication skills of socialized canids may help to understand the evolution and the epigenesis of gesture comprehension in humans. To reconcile previously contradicting views on the origin of dogs' outstanding performance in utilizing human gestures, we suggest that dog-wolf differences should be studied in a more complex way.We present data both on the performance and the behaviour of dogs and wolves of different ages in a two-way object choice test. Characteristic behavioural differences showed that for wolves it took longer to establish eye contact with the pointing experimenter, they struggled more with the handler, and pups also bit her more before focusing on the human's signal. The performance of similarly hand-reared 8-week-old dogs and wolves did not differ in utilizing the simpler proximal momentary pointing. However, when tested with the distal momentary pointing, 4-month-old pet dogs outperformed the same aged hand reared wolves. Thus early and intensive socialisation does not diminish differences between young dogs and wolves in behaviour and performance. Socialised adult wolves performed similarly well as dogs in this task without pretraining. The success of adult wolves was accompanied with increased willingness to cooperate.Thus, we provide evidence for the first time that socialised adult wolves are as successful in relying on distal momentary pointing as adult pet dogs. However, the delayed emergence of utilising human distal momentary pointing in wolves shows that these wild canines react to a lesser degree to intensive socialisation in contrast to dogs, which are able to control agonistic behaviours and inhibition of actions in a food related task early in development. We suggest a "synergistic" hypothesis, claiming that positive feedback processes (both evolutionary and epigenetic have increased the readiness of dogs to attend to humans, providing the basis for dog-human communication.

  6. Explaining dog wolf differences in utilizing human pointing gestures: selection for synergistic shifts in the development of some social skills.

    Science.gov (United States)

    Gácsi, Márta; Györi, Borbála; Gyoöri, Borbála; Virányi, Zsófia; Kubinyi, Enikö; Range, Friederike; Belényi, Beatrix; Miklósi, Adám

    2009-08-28

    The comparison of human related communication skills of socialized canids may help to understand the evolution and the epigenesis of gesture comprehension in humans. To reconcile previously contradicting views on the origin of dogs' outstanding performance in utilizing human gestures, we suggest that dog-wolf differences should be studied in a more complex way. We present data both on the performance and the behaviour of dogs and wolves of different ages in a two-way object choice test. Characteristic behavioural differences showed that for wolves it took longer to establish eye contact with the pointing experimenter, they struggled more with the handler, and pups also bit her more before focusing on the human's signal. The performance of similarly hand-reared 8-week-old dogs and wolves did not differ in utilizing the simpler proximal momentary pointing. However, when tested with the distal momentary pointing, 4-month-old pet dogs outperformed the same aged hand reared wolves. Thus early and intensive socialisation does not diminish differences between young dogs and wolves in behaviour and performance. Socialised adult wolves performed similarly well as dogs in this task without pretraining. The success of adult wolves was accompanied with increased willingness to cooperate. Thus, we provide evidence for the first time that socialised adult wolves are as successful in relying on distal momentary pointing as adult pet dogs. However, the delayed emergence of utilising human distal momentary pointing in wolves shows that these wild canines react to a lesser degree to intensive socialisation in contrast to dogs, which are able to control agonistic behaviours and inhibition of actions in a food related task early in development. We suggest a "synergistic" hypothesis, claiming that positive feedback processes (both evolutionary and epigenetic) have increased the readiness of dogs to attend to humans, providing the basis for dog-human communication.

  7. Extreme population differences in the human zinc transporter ZIP4 (SLC39A4 are explained by positive selection in Sub-Saharan Africa.

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    Johannes Engelken

    2014-02-01

    Full Text Available Extreme differences in allele frequency between West Africans and Eurasians were observed for a leucine-to-valine substitution (Leu372Val in the human intestinal zinc uptake transporter, ZIP4, yet no further evidence was found for a selective sweep around the ZIP4 gene (SLC39A4. By interrogating allele frequencies in more than 100 diverse human populations and resequencing Neanderthal DNA, we confirmed the ancestral state of this locus and found a strong geographical gradient for the derived allele (Val372, with near fixation in West Africa. In extensive coalescent simulations, we show that the extreme differences in allele frequency, yet absence of a classical sweep signature, can be explained by the effect of a local recombination hotspot, together with directional selection favoring the Val372 allele in Sub-Saharan Africans. The possible functional effect of the Leu372Val substitution, together with two pathological mutations at the same codon (Leu372Pro and Leu372Arg that cause acrodermatitis enteropathica (a disease phenotype characterized by extreme zinc deficiency, was investigated by transient overexpression of human ZIP4 protein in HeLa cells. Both acrodermatitis mutations cause absence of the ZIP4 transporter cell surface expression and nearly absent zinc uptake, while the Val372 variant displayed significantly reduced surface protein expression, reduced basal levels of intracellular zinc, and reduced zinc uptake in comparison with the Leu372 variant. We speculate that reduced zinc uptake by the ZIP4-derived Val372 isoform may act by starving certain pathogens of zinc, and hence may have been advantageous in Sub-Saharan Africa. Moreover, these functional results may indicate differences in zinc homeostasis among modern human populations with possible relevance for disease risk.

  8. The Protective Effect of Low-Dose Aspirin against Colorectal Cancer Is Unlikely Explained by Selection Bias: Results from Three Different Study Designs in Clinical Practice.

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    Lucía Cea Soriano

    Full Text Available We conducted three differently designed nested case-control studies to evaluate whether the protective effect of low-dose aspirin against colorectal cancer (CRC is explained by selection bias.Using a large validated UK primary care database, we followed different cohorts of patients, who varied in their demographic and clinical characteristics, to identify first ever cases of CRC. In Studies 1 and 2, two cohorts were followed, i new users of low-dose aspirin at start of follow-up (N = 170,336 in Study 1, N = 171,527 in Study 2 and either ii non-users of low-dose aspirin (Study 1, N = 170,336 or new users of paracetamol (Study 2, N = 149,597 at start of follow-up. In Study 3 a single cohort of individuals näive to low-dose aspirin at the start of observation was followed. Controls were selected using incidence sampling and logistic regression used to obtain an unbiased estimate of the incidence rate ratio (RR with 95% confidence intervals (CIs. Low-dose aspirin exposure was analyzed 'as-treated' before the index date (CRC date for cases, random date for controls.In the three studies, median (maximum follow-up was 5.1 (12, 5.8 (12 and 7.5 (13 years, respectively. 3033 incident CRC cases were identified in Study 1, 3174 in Study 2, and 12,333 in Study 3. Current use of low-dose aspirin was associated with a significantly reduced risk of 34%, 29% and 31% in the three studies, respectively; corresponding RRs (95% CIs were 0.66 (0.60-0.73, 0.71 (0.63-0.80 and 0.69 (0.64-0.74. In each study, significantly reduced risks of CRC were seen when low-dose aspirin was used for primary or secondary cardiovascular disease prevention, in both sexes, and across all age groups evaluated.Low-dose aspirin is associated with a significantly reduced risk of CRC. The consistency of our findings across different studies makes selection bias an unlikely explanation.

  9. The Protective Effect of Low-Dose Aspirin against Colorectal Cancer Is Unlikely Explained by Selection Bias: Results from Three Different Study Designs in Clinical Practice.

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    Cea Soriano, Lucía; Soriano-Gabarró, Montse; García Rodríguez, Luis A

    2016-01-01

    We conducted three differently designed nested case-control studies to evaluate whether the protective effect of low-dose aspirin against colorectal cancer (CRC) is explained by selection bias. Using a large validated UK primary care database, we followed different cohorts of patients, who varied in their demographic and clinical characteristics, to identify first ever cases of CRC. In Studies 1 and 2, two cohorts were followed, i) new users of low-dose aspirin at start of follow-up (N = 170,336 in Study 1, N = 171,527 in Study 2) and either ii) non-users of low-dose aspirin (Study 1, N = 170,336) or new users of paracetamol (Study 2, N = 149,597) at start of follow-up. In Study 3 a single cohort of individuals näive to low-dose aspirin at the start of observation was followed. Controls were selected using incidence sampling and logistic regression used to obtain an unbiased estimate of the incidence rate ratio (RR) with 95% confidence intervals (CIs). Low-dose aspirin exposure was analyzed 'as-treated' before the index date (CRC date for cases, random date for controls). In the three studies, median (maximum) follow-up was 5.1 (12), 5.8 (12) and 7.5 (13) years, respectively. 3033 incident CRC cases were identified in Study 1, 3174 in Study 2, and 12,333 in Study 3. Current use of low-dose aspirin was associated with a significantly reduced risk of 34%, 29% and 31% in the three studies, respectively; corresponding RRs (95% CIs) were 0.66 (0.60-0.73), 0.71 (0.63-0.80) and 0.69 (0.64-0.74). In each study, significantly reduced risks of CRC were seen when low-dose aspirin was used for primary or secondary cardiovascular disease prevention, in both sexes, and across all age groups evaluated. Low-dose aspirin is associated with a significantly reduced risk of CRC. The consistency of our findings across different studies makes selection bias an unlikely explanation.

  10. Explaining the Sex Difference in Dyslexia

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    Arnett, Anne B.; Pennington, Bruce F.; Peterson, Robin L.; Willcutt, Erik G.; DeFries, John C.; Olson, Richard K.

    2017-01-01

    Background: Males are diagnosed with dyslexia more frequently than females, even in epidemiological samples. This may be explained by greater variance in males' reading performance. Methods: We expand on previous research by rigorously testing the variance difference theory, and testing for mediation of the sex difference by cognitive correlates.…

  11. Relevance theory explains the selection task.

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    Sperber, D; Cara, F; Girotto, V

    1995-10-01

    We propose a general and predictive explanation of the Wason Selection Task (where subjects are asked to select evidence for testing a conditional "rule"). Our explanation is based on a reanalysis of the task, and on Relevance Theory. We argue that subjects' selections in all true versions of the Selection Task result from the following procedure. Subjects infer from the rule directly testable consequences. They infer them in their order of accessibility, and stop when the resulting interpretation of the rule meets their expectations of relevance. Subjects then select the cards that may test the consequences they have inferred from the rule. Order of accessibility of consequences and expectations of relevance vary with rule and context, and so, therefore, does subjects' performance. By devising appropriate rule-context pairs, we predict that correct performance can be elicited in any conceptual domain. We corroborate this prediction with four experiments. We argue that past results properly reanalyzed confirm our account. We discuss the relevance of the Selection Task to the study of reasoning.

  12. Can selection explain the protective effects of farming on asthma?

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    Wijnand Eduard

    2015-09-01

    No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.

  13. Good for the group? Explaining apparent group-level selection

    NARCIS (Netherlands)

    Smallegange, I.M.; Egas, M.

    2015-01-01

    The idea that group selection can explain adaptive trait evolution is still controversial. Recent empirical work proposes evidence for group-level adaptation in a social spider, but the findings can also be explained from an individual-level perspective. The challenge remains to identify situations

  14. Personality differences explain leadership in barnacle geese

    NARCIS (Netherlands)

    Kurvers, R.H.J.M.; Eijkelenkamp, B.; Van Oers, K.; van Lith, B.; van Wieren, S.E.; Ydenberg, R.C.; Prins, H.H.T.

    2009-01-01

    Personality in animal behaviour describes the observation that behavioural differences between individuals are consistent over time and context. Studies of group-living animals show that movement order among individuals is also consistent over time and context, suggesting that some individuals lead

  15. Do sex differences in rumination explain sex differences in depression?

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    Shors, Tracey J; Millon, Emma M; Chang, Han Yan M; Olson, Ryan L; Alderman, Brandon L

    2017-01-02

    It is generally accepted that women tend to ruminate more than men do and these thought patterns are often associated with depressive symptoms (Nolen-Hoeksema et al., ). Based on these findings, we considered whether the relationship between rumination and depression is stronger in women than in men and if so, whether this might explain the higher prevalence of major depressive disorder (MDD) in women and finally, whether the association can be disrupted through a mind/body intervention. Adult men and women, most of whom were clinically depressed, participated in an intervention known as MAP Training, which combines "mental" training with silent meditation and "physical" training with aerobic exercise (Shors et al., ). After eight weeks of training, both men and women reported significantly fewer symptoms of depression and fewer ruminative thoughts (Alderman et al., ). Statistical correlations between depressive symptoms and ruminative thoughts were strong and significant (rho > 0.50; p women before and after MAP Training. However, only in women did depressive symptoms relate to "reflective" ruminations, which involve analyses of past events, feelings, and behaviors. This is also the only relationship that dissipated after the intervention. In general, these analyses suggest that the strength of the relationship between depressive symptoms and rumination does not necessarily explain sex differences in depression; but because the relationship is strong, targeting rumination through intervention can reduce the incidence of MDD, which is more prevalent among women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. A Conceptual Characterization of Online Videos Explaining Natural Selection

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    Bohlin, Gustav; Göransson, Andreas; Höst, Gunnar E.; Tibell, Lena A. E.

    2017-01-01

    Educational videos on the Internet comprise a vast and highly diverse source of information. Online search engines facilitate access to numerous videos claiming to explain natural selection, but little is known about the degree to which the video content match key evolutionary content identified as important in evolution education research. In…

  17. Metabolic responses to high-fat diets rich in n-3 or n-6 long-chain polyunsaturated fatty acids in mice selected for either high body weight or leanness explain different health outcomes

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    Nuernberg Karin

    2011-08-01

    Full Text Available Abstract Background Increasing evidence suggests that diets high in polyunsaturated fatty acids (PUFA confer health benefits by improving insulin sensitivity and lipid metabolism in liver, muscle and adipose tissue. Methods The present study investigates metabolic responses in two different lines of mice either selected for high body weight (DU6 leading to rapid obesity development, or selected for high treadmill performance (DUhTP leading to a lean phenotype. At 29 days of age the mice were fed standard chow (7.2% fat, 25.7% protein, or a high-fat diet rich in n-3 PUFA (n-3 HFD, 27.7% fat, 19% protein or a high-fat diet rich in n-6 PUFA (n-6 HFD, 27.7% fat, 18.6% protein for 8 weeks. The aim of the study was to determine the effect of these PUFA-rich high-fat diets on the fatty acid profile and on the protein expression of key components of insulin signalling pathways. Results Plasma concentrations of leptin and insulin were higher in DU6 in comparison with DUhTP mice. The high-fat diets stimulated a strong increase in leptin levels and body fat only in DU6 mice. Muscle and liver fatty acid composition were clearly changed by dietary lipid composition. In both lines of mice n-3 HFD feeding significantly reduced the hepatic insulin receptor β protein concentration which may explain decreased insulin action in liver. In contrast, protein kinase C ζ expression increased strongly in abdominal fat of n-3 HFD fed DUhTP mice, indicating enhanced insulin sensitivity in adipose tissue. Conclusions A diet high in n-3 PUFA may facilitate a shift from fuel deposition in liver to fuel storage as fat in adipose tissue in mice. Tissue specific changes in insulin sensitivity may describe, at least in part, the health improving properties of dietary n-3 PUFA. However, important genotype-diet interactions may explain why such diets have little effect in some population groups.

  18. Can selection explain the protective effects of farming on asthma?

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    Eduard, Wijnand; Schlünssen, Vivi; Sigsgaard, Torben; Omland, Øyvind; Pearce, Neil; Douwes, Jeroen

    2015-01-01

    Reduced asthma and allergy risks in farmers have been ascribed to microbial exposures. However, selection may also play a role and this was assessed in two Scandinavian farming populations. Asthma prevalence in 739 Danish farming students was compared to that of 1,105 siblings. 8,482 Norwegian farmers were also compared with 349 early retired farmers. The prevalence of ever-asthma was 5.4% in farming students and 5.2% in siblings (OR 1.1; 95%CI 0.73-1.7). Current asthma in farmers was 3.0% compared to 6.3% in farmers who had retired early (OR 1.8, 95%CI 1.1-2.9). Adjustments for early retirement increased the asthma prevalence by 0.3-0.6%. Farmers who had changed production were more likely to have asthma (OR 9.8, 95% CI 6.0-16). No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.

  19. Can selection explain the protective effects of farming on asthma?

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    Wijnand Eduard

    2015-09-01

    Full Text Available [i][/i]Introduction and objective. Reduced asthma and allergy risks in farmers have been ascribed to microbial exposures. However, selection may also play a role and this was assessed in two Scandinavian farming populations. Materials and methods. Asthma prevalence in 739 Danish farming students was compared to that of 1,105 siblings. 8,482 Norwegian farmers were also compared with 349 early retired farmers. Results. The prevalence of ever-asthma was 5.4% in farming students and 5.2% in siblings (OR 1.1; 95%CI 0.73–1.7. Current asthma in farmers was 3.0% compared to 6.3% in farmers who had retired early (OR 1.8, 95%CI 1.1–2.9. Adjustments for early retirement increased the asthma prevalence by 0.3–0.6%. Farmers who had changed production were more likely to have asthma (OR 9.8, 95% CI 6.0–16. Conclusions. No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.

  20. A Conceptual Characterization of Online Videos Explaining Natural Selection

    Science.gov (United States)

    Bohlin, Gustav; Göransson, Andreas; Höst, Gunnar E.; Tibell, Lena A. E.

    2017-11-01

    Educational videos on the Internet comprise a vast and highly diverse source of information. Online search engines facilitate access to numerous videos claiming to explain natural selection, but little is known about the degree to which the video content match key evolutionary content identified as important in evolution education research. In this study, we therefore analyzed the content of 60 videos accessed through the Internet, using a criteria catalog with 38 operationalized variables derived from research literature. The variables were sorted into four categories: (a) key concepts (e.g. limited resources and inherited variation), (b) threshold concepts (abstract concepts with a transforming and integrative function), (c) misconceptions (e.g. that evolution is driven by need), and (d) organismal context (e.g. animal or plant). The results indicate that some concepts are frequently communicated, and certain taxa are commonly used to illustrate concepts, while others are seldom included. In addition, evolutionary phenomena at small temporal and spatial scales, such as subcellular processes, are rarely covered. Rather, the focus is on population-level events over time scales spanning years or longer. This is consistent with an observed lack of explanations regarding how randomly occurring mutations provide the basis for variation (and thus natural selection). The findings imply, among other things, that some components of natural selection warrant far more attention in biology teaching and science education research.

  1. Do Prices and Attributes Explain International Differences in Food Purchases?

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    Dubois, Pierre; Griffith, Rachel; Nevo, Aviv

    2014-01-01

    Food purchases differ substantially across countries. We use detailed household level data from the US, France and the UK to (i) document these differences; (ii) esti- mate a demand system for food and nutrients, and (iii) simulate counterfactual choices if households faced prices and nutritional characteristics from other countries. We find that differences in prices and characteristics are important and can explain some difference (e.g., US-France difference in caloric intake), but generall...

  2. Can chunk size differences explain developmental changes in lexical learning?

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    Eleonore H.M. Smalle

    2016-01-01

    Full Text Available In three experiments, we investigated Hebb repetition learning (HRL differences between children and adults, as a function of the type of item (lexical vs. sub-lexical and the level of item-overlap between sequences. In a first experiment, it was shown that when non-repeating and repeating (Hebb sequences of words were all permutations of the same words, HRL was slower than when the sequences shared no words. This item-overlap effect was observed in both children and adults. In a second experiment, we used syllable sequences and we observed reduced HRL due to item-overlap only in children. The findings are explained within a chunking account of the HRL effect on the basis of which we hypothesize that children, compared with adults, chunk syllable sequences in smaller units. By hypothesis, small chunks are more prone to interference from anagram representations included in the filler sequences, potentially explaining the item-overlap effect in children. This hypothesis was tested in a third experiment with adults where we experimentally manipulated the chunk size by embedding pauses in the syllable sequences. Interestingly, we showed that imposing a small chunk size caused adults to show the same behavioral effects as those observed in children. Departing from the analogy between verbal HRL and lexical development, the results are discussed in light of the less-is-more hypothesis of age-related differences in language acquisition.

  3. Can Chunk Size Differences Explain Developmental Changes in Lexical Learning?

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    Smalle, Eleonore H M; Bogaerts, Louisa; Simonis, Morgane; Duyck, Wouter; Page, Michael P A; Edwards, Martin G; Szmalec, Arnaud

    2015-01-01

    In three experiments, we investigated Hebb repetition learning (HRL) differences between children and adults, as a function of the type of item (lexical vs. sub-lexical) and the level of item-overlap between sequences. In a first experiment, it was shown that when non-repeating and repeating (Hebb) sequences of words were all permutations of the same words, HRL was slower than when the sequences shared no words. This item-overlap effect was observed in both children and adults. In a second experiment, we used syllable sequences and we observed reduced HRL due to item-overlap only in children. The findings are explained within a chunking account of the HRL effect on the basis of which we hypothesize that children, compared with adults, chunk syllable sequences in smaller units. By hypothesis, small chunks are more prone to interference from anagram representations included in the filler sequences, potentially explaining the item-overlap effect in children. This hypothesis was tested in a third experiment with adults where we experimentally manipulated the chunk size by embedding pauses in the syllable sequences. Interestingly, we showed that imposing a small chunk size caused adults to show the same behavioral effects as those observed in children. Departing from the analogy between verbal HRL and lexical development, the results are discussed in light of the less-is-more hypothesis of age-related differences in language acquisition.

  4. Strong selection barriers explain microgeographic adaptation in wild salamander populations.

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    Richardson, Jonathan L; Urban, Mark C

    2013-06-01

    Microgeographic adaptation occurs when populations evolve divergent fitness advantages across the spatial scales at which focal organisms regularly disperse. Although an increasing number of studies find evidence for microgeographic adaptation, the underlying causes often remain unknown. Adaptive divergence requires some combination of limited gene flow and strong divergent natural selection among populations. In this study, we estimated the relative influence of selection, gene flow, and the spatial arrangement of populations in shaping patterns of adaptive divergence in natural populations of the spotted salamander (Ambystoma maculatum). Within the study region, A. maculatum co-occur with the predatory marbled salamander (Ambystoma opacum) in some ponds, and past studies have established a link between predation risk and adaptive trait variation in A. maculatum. Using 14 microsatellite loci, we found a significant pattern of genetic divergence among A. maculatum populations corresponding to levels of A. opacum predation risk. Additionally, A. maculatum foraging rate was strongly associated with predation risk, genetic divergence, and the spatial relationship of ponds on the landscape. Our results indicate the sorting of adaptive genotypes by selection regime and strongly suggest that substantial selective barriers operate against gene flow. This outcome suggests that microgeographic adaptation in A. maculatum is possible because strong antagonistic selection quickly eliminates maladapted phenotypes despite ongoing and substantial immigration. Increasing evidence for microgeographic adaptation suggests a strong role for selective barriers in counteracting the homogenizing influence of gene flow. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  5. Differences in codon bias cannot explain differences in translational power among microbes

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    Dethlefsen Les

    2005-01-01

    Full Text Available Abstract Background Translational power is the cellular rate of protein synthesis normalized to the biomass invested in translational machinery. Published data suggest a previously unrecognized pattern: translational power is higher among rapidly growing microbes, and lower among slowly growing microbes. One factor known to affect translational power is biased use of synonymous codons. The correlation within an organism between expression level and degree of codon bias among genes of Escherichia coli and other bacteria capable of rapid growth is commonly attributed to selection for high translational power. Conversely, the absence of such a correlation in some slowly growing microbes has been interpreted as the absence of selection for translational power. Because codon bias caused by translational selection varies between rapidly growing and slowly growing microbes, we investigated whether observed differences in translational power among microbes could be explained entirely by differences in the degree of codon bias. Although the data are not available to estimate the effect of codon bias in other species, we developed an empirically-based mathematical model to compare the translation rate of E. coli to the translation rate of a hypothetical strain which differs from E. coli only by lacking codon bias. Results Our reanalysis of data from the scientific literature suggests that translational power can differ by a factor of 5 or more between E. coli and slowly growing microbial species. Using empirical codon-specific in vivo translation rates for 29 codons, and several scenarios for extrapolating from these data to estimates over all codons, we find that codon bias cannot account for more than a doubling of the translation rate in E. coli, even with unrealistic simplifying assumptions that exaggerate the effect of codon bias. With more realistic assumptions, our best estimate is that codon bias accelerates translation in E. coli by no more than

  6. What explains between-school differences in rates of smoking?

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    Wight Daniel

    2008-06-01

    Full Text Available Abstract Background Schools have the potential to influence their pupils' behaviour through the school's social organisation and culture (non-formal school characteristics, as well as through the formal curriculum. This paper examines whether these school characteristics (which include a measure of quality of social relationships can account for school differences in smoking rates. Methods This study uses a longitudinal survey involving 5,092 pupils in 24 Scottish schools. Pupils' smoking (at age 15/16, cognitive measures, attitude to school and pupils' rating of teacher pupil relationships (at age 13/14 were linked to school level data comprising teacher assessed quality of pupil-staff relationships, school level deprivation, staying on rates and attendance. Analysis involved multi-level modelling. Results Overall, 25% of males and 39% of females reported smoking, with rates by school ranging from 8% to 33% for males and from 28% to 49% for females. When individual socio-economic and socio-cultural factors were controlled for there was still a large school effect for males and a smaller (but correlated school effect for females at 15/16 years. For girls their school effect was explained by their rating of teacher-pupil relationships and attitude to school. These variables were also significant in predicting smoking among boys. However, the school effect for boys was most radically attenuated and became insignificant when the interaction between poor quality of teacher – pupil relationships and school level affluence was fitted, explaining 82% of the variance between schools. In addition, researchers' rating of the schools' focus on caring and inclusiveness was also significantly associated with both male and female smoking rates. Conclusion School-level characteristics have an impact on male and female pupils' rates of smoking up to 15/16 years of age. The size of the school effect is greater for males at this age. The social environment of

  7. Can Institutions Explain Cross-Country Differences in Innovative Activity?

    DEFF Research Database (Denmark)

    Wang, Cong

    2013-01-01

    Motivated by theoretical arguments (see e.g. Romer (2010) and Mokyr (2008)) that assert a positive impact of institutions on R&D, this paper aims to provide some empirical analysis on the relationship between the two variables. In particular, using a core sample of 98 countries over the period 19....... This paper has also found evidence that the effect of institutions varies in different economies characterized by different levels of financial development and human capital accumulation, but stays relatively unchanged across countries with different levels of trade openness....

  8. Structural Differences Explain Diverse Functions of Plasmodium Actins

    Science.gov (United States)

    Vahokoski, Juha; Martinez, Silvia Muñico; Ignatev, Alexander; Lepper, Simone; Frischknecht, Friedrich; Sidén-Kiamos, Inga; Sachse, Carsten; Kursula, Inari

    2014-01-01

    Actins are highly conserved proteins and key players in central processes in all eukaryotic cells. The two actins of the malaria parasite are among the most divergent eukaryotic actins and also differ from each other more than isoforms in any other species. Microfilaments have not been directly observed in Plasmodium and are presumed to be short and highly dynamic. We show that actin I cannot complement actin II in male gametogenesis, suggesting critical structural differences. Cryo-EM reveals that Plasmodium actin I has a unique filament structure, whereas actin II filaments resemble canonical F-actin. Both Plasmodium actins hydrolyze ATP more efficiently than α-actin, and unlike any other actin, both parasite actins rapidly form short oligomers induced by ADP. Crystal structures of both isoforms pinpoint several structural changes in the monomers causing the unique polymerization properties. Inserting the canonical D-loop to Plasmodium actin I leads to the formation of long filaments in vitro. In vivo, this chimera restores gametogenesis in parasites lacking actin II, suggesting that stable filaments are required for exflagellation. Together, these data underline the divergence of eukaryotic actins and demonstrate how structural differences in the monomers translate into filaments with different properties, implying that even eukaryotic actins have faced different evolutionary pressures and followed different paths for developing their polymerization properties. PMID:24743229

  9. Explaining Differences in Learning Outcomes in Auditing Education

    DEFF Research Database (Denmark)

    Holm, Claus; Steenholdt, Niels

    In this paper we use a learner perspective on learning outcomes which reflects that some students taking accounting classes are also provided with on-the-job training in accounting firms. Hence knowledge about learning outcomes for different groups of students is essential information for educators...... as well as the accounting profession. This paper extends prior research on the role of declarative and procedural knowledge in performing auditing tasks. Measuring learning outcomes is a complex matter requiring sensible measures for both declarative knowledge (ability to verbalize pertinent facts...... or processes) and procedural knowledge (intellectual skills). The performance of 75 graduate accounting students representing both types of schema is examined. The findings suggest that differences in learning outcomes may be attributed to differences in student background and prior knowledge (auditing...

  10. Explaining Differences in Learning Outcomes in Auditing Education

    DEFF Research Database (Denmark)

    Holm, Claus; Steenholdt, Niels

    2014-01-01

    In this paper we use a learner perspective on learning outcomes which reflects that some students taking accounting classes are also provided with on-the-job training in accounting firms. Hence knowledge about learning outcomes for different groups of students is essential information for educators...... as well as the accounting profession. This paper extends prior research on the role of declarative and procedural knowledge in performing auditing tasks. Measuring learning outcomes is a complex matter requiring sensible measures for both declarative knowledge (ability to verbalize pertinent facts...... or processes) and procedural knowledge (intellectual skills). The performance of 75 graduate accounting students representing both types of schema is examined. The findings suggest that differences in learning outcomes may be attributed to differences in student background and prior knowledge (auditing...

  11. Sexual selection on land snail shell ornamentation: a hypothesis that may explain shell diversity

    Directory of Open Access Journals (Sweden)

    Schilthuizen Menno

    2003-06-01

    Full Text Available Abstract Background Many groups of land snails show great interspecific diversity in shell ornamentation, which may include spines on the shell and flanges on the aperture. Such structures have been explained as camouflage or defence, but the possibility that they might be under sexual selection has not previously been explored. Presentation of the hypothesis The hypothesis that is presented consists of two parts. First, that shell ornamentation is the result of sexual selection. Second, that such sexual selection has caused the divergence in shell shape in different species. Testing the hypothesis The first part of the hypothesis may be tested by searching for sexual dimorphism in shell ornamentation in gonochoristic snails, by searching for increased variance in shell ornamentation relative to other shell traits, and by mate choice experiments using individuals with experimentally enhanced ornamentation. The second part of the hypothesis may be tested by comparing sister groups and correlating shell diversity with degree of polygamy. Implications of the hypothesis If the hypothesis were true, it would provide an explanation for the many cases of allopatric evolutionary radiation in snails, where shell diversity cannot be related to any niche differentiation or environmental differences.

  12. Explaining Gender Inequality in Iceland: What Makes the Difference?

    Science.gov (United States)

    Heijstra, Thamar M.; O'Connor, Pat; Rafnsdóttir, Gudbjörg Linda

    2013-01-01

    This article examines the explanations offered by men and women, at different academic ranks, for the scarcity of women in full professorial positions in Icelandic universities. Data derive from interviews and a survey involving the total Icelandic academic population. We test three hypotheses: Firstly, academics will not see family…

  13. Beyond Access: Explaining Socioeconomic Differences in College Transfer

    Science.gov (United States)

    Goldrick-Rab, Sara; Pfeffer, Fabian T.

    2009-01-01

    Reducing socioeconomic differences in college transfer requires understanding how and why parental education, occupational class, and family income are associated with changing colleges. Building on prior studies of traditional community college transfer, the authors explore relationships between those factors and two types of transfer among…

  14. Explaining Couple Cohesion in Different Types of Gay Families

    Science.gov (United States)

    van Eeden-Moorefield, Brad; Pasley, Kay; Crosbie-Burnett, Margaret; King, Erin

    2012-01-01

    This Internet-based study used data from a convenience sample of 176 gay men in current partnerships to examine differences in outness, cohesion, and relationship quality between three types of gay male couples: first cohabiting partnerships, repartnerships, and gay stepfamilies. Also, we tested whether relationship quality mediated the link…

  15. Can Reporting Heterogeneity Explain Differences in Depressive Symptoms across Europe?

    Science.gov (United States)

    Kok, Renske; Avendano, Mauricio; d'Uva, Teresa Bago; Mackenbach, Johan

    2012-01-01

    Depression is one of the leading causes of disability in the developed world. Previous studies have shown varying depression prevalence rates between European countries, and also within countries, between socioeconomic groups. However, it is unclear whether these differences reflect true variations in prevalence or whether they are attributable to…

  16. What explains between-school differences in rates of smoking?

    OpenAIRE

    Wight Daniel; Ecob Russell; Henderson Marion; Abraham Charles

    2008-01-01

    Abstract Background Schools have the potential to influence their pupils' behaviour through the school's social organisation and culture (non-formal school characteristics), as well as through the formal curriculum. This paper examines whether these school characteristics (which include a measure of quality of social relationships) can account for school differences in smoking rates. Methods This study uses a longitudinal survey involving 5,092 pupils in 24 Scottish schools. Pupils' smoking (...

  17. Explaining turnover intention in Korean public community hospitals: occupational differences.

    Science.gov (United States)

    Hwang, Jee-In; Chang, Hyejung

    2008-01-01

    Personnel in public hospitals had relatively low job satisfaction despite of tenure employment. High turnover rates degrade hospital image and incur additional costs related to recruitment and training. The purposes of this study were to describe the occupational differences and to identify factors affecting turnover intention among public hospital personnel. A questionnaire survey was conducted as part of Administrative Services Quality Evaluation Program by Seoul metropolitan municipality from 1 November to 1 December in 2003. The subjects were 1251 entire hospital personnel in four hospitals. The questionnaire was designed to measure job satisfaction, organizational commitment, turnover intention, and demographic characteristics. Logistic regression analysis was performed to determine factors influencing turnover intention. There were significant differences in job satisfaction, organizational commitment, and turnover intention according to the occupations. The turnover intention rates were highest among physicians, followed by paramedicals and nursing staffs and then administrators. The significant factors affecting turnover intention were involvement and loyalty among physicians, hospital type, satisfaction with systems and loyalty among nursing staffs, satisfaction with relationship and loyalty among administrators, and loyalty among paramedicals. There were different moderators that influence turnover intentions of hospital personnel. Loyalty had the most important effect upon turnover intention in all occupations. 2007 John Wiley & Sons, Ltd

  18. Gender differences in inflammatory bowel disease: Explaining body image dissatisfaction.

    Science.gov (United States)

    Trindade, Inês A; Ferreira, Cláudia; Duarte, Cristiana; Pinto-Gouveia, José

    2017-12-01

    The aim of this study was to examine the role of body image problems in the context of inflammatory bowel disease and to explore gender differences in these associations. A sample of inflammatory bowel disease patients (60 males and 140 females) was collected. Findings from a multi-group analysis show that inflammatory bowel disease symptomatology may impact on body image in both male and female patients through the effect of body-image-related cognitive fusion. Body image difficulties in the context of inflammatory bowel disease should not be a neglected dimension in research aiming at understanding the psychosocial effects of inflammatory bowel disease and by health professionals working with these patients.

  19. Can market structure explain cross-country differences in health?

    Directory of Open Access Journals (Sweden)

    Kate Rybczynski

    2013-03-01

    Full Text Available There is a well documented health disparity between several European countries and the United States. This health gap remains even after controlling for socioeconomic status and risk factors. At the same time, we note that the U.S. market structure is characterized by significantly more large corporations and "super-sized" retail outlets than Europe. Because big business is hierarchical in nature and has been reported to engender urban sprawl, inferior work environments, and loss of social capital, all identified as correlates of poor health, we suggest that differences in market structure may help account for some of the unexplained differences in health across Europe and North America. Using national level data, this study explores the relationship between market structure and health. We investigate whether individuals who live in countries with proportionately more small business are healthier than those who do not. We use two measures of national health: life expectancy at birth, and age-standardized estimates of diabetes rates. Results from ordinary least squares regressions suggest that, there is a large and statistically significant association between market structure (the ratio of small to total businesses and health, even after controlling income, public percent of health expenditure, and obesity rates. This association is robust to additional controls such as insufficient physical activity, smoking, alcohol disease, and air pollution.

  20. Explaining Differences in Scientific Expertise Use: The Politics of Pesticides

    Directory of Open Access Journals (Sweden)

    Dovilė Rimkutė

    2015-03-01

    Full Text Available Despite the growing importance of EU regulatory agencies in European decision-making, academic literature is missing a systematic explanation of how regulatory agencies actually contend with their core tasks of providing scientific advice to EU institutions. The article contributes to the theoretical explanation of when and under what conditions different uses of scientific expertise prevail. In particular, it focuses on theoretical explanations leading to strategic substantiating use of expertise followed by an empirical analysis of single case research. Substantiating expertise use refers to those practices in which an organisation seeks to promote and justify its predetermined preferences, which are based on certain values, political or economic interests. Empirical findings are discussed in the light of the theoretical expectations derived by streamlining and combining the main arguments of classical organisational and institutional theories and recent academic research. Process-tracing techniques are applied to investigate the process by which an EU regulation restricting the use of neonicotinoid pesticides (European Commission, 2013 was developed. The empirical analysis combines a variety of data sources including official documents, press releases, scientific outputs, and semi-structured interviews with the academic and industry experts involved in the process. The study finds that the interaction between high external pressure and high internal capacity leads to the strategic substantiating use of expertise, in which scientific evidence is used to promote the inclinations of actors upon which the agency depends most.

  1. Putting the social into social learning: explaining both selectivity and fidelity in children's copying behavior.

    Science.gov (United States)

    Over, Harriet; Carpenter, Malinda

    2012-05-01

    Many previous accounts of imitation have pointed out that children's copying behavior is a means by which to learn from others, while virtually ignoring the social factors which influence imitation. These accounts have thus far been unable to explain flexibility in children's copying behavior (e.g., why children sometimes copy exactly and sometimes copy selectively). We propose that the complexity of children's imitation can only be fully understood by considering the social context in which it is produced. Three critical factors in determining what is copied are children's own (learning and/or social) goals in the situation, children's identification with the model and with the social group in general, and the social pressures which children experience within the imitative situation. The specific combination of these factors which is present during the imitative interaction can lead children to produce a more or less faithful reproduction of the model's act. Beyond explaining flexibility in children's copying behavior, this approach situates the developmental study of imitation within a broader social psychological framework, linking it conceptually with closely related topics such as mimicry, conformity, normativity, and the cultural transmission of group differences.

  2. Spatial modelling of Calanus finmarchicus and Calanus helgolandicus: parameter differences explain differences in biogeography

    Directory of Open Access Journals (Sweden)

    Robert John Wilson

    2016-09-01

    Full Text Available The North Atlantic copepods Calanus finmarchicus and C. helgolandicus are moving north in response to rising temperatures. Understanding the drivers of their relative geographic distributions is required in order to anticipate future changes. To explore this, we created a new spatially explicit stage-structured model of their populations throughout the North Atlantic. Recent advances in understanding Calanus biology, including U-shaped relationships between growth and fecundity and temperature, and a new model of diapause duration are incorporated in the model. Equations were identical for both species, but some parameters were species-specific. The model was parameterized using Continuous Plankton Recorder Survey data and tested using time series of abundance and fecundity. The geographic distributions of both species were reproduced by assuming that only known interspecific differences and a difference in the temperature influence on mortality exist. We show that differences in diapause capability are not necessary to explain why C. helgolandicus is restricted to the continental shelf. Smaller body size and higher overwinter temperatures likely make true diapause implausible for C. helgolandicus. Known differences were incapable of explaining why only C. helgolandicus exists southwest of the British Isles. Further, the fecundity of C. helgolandicus in the English Channel is much lower than we predict. We hypothesize that food quality is a key influence on the population dynamics of these species. The modelling framework presented can potentially be extended to further Calanus species.

  3. Sexual selection on land snail shell ornamentation: a hypothesis that may explain shell diversity

    NARCIS (Netherlands)

    Schilthuizen, M.

    2003-01-01

    Background: Many groups of land snails show great interspecific diversity in shell ornamentation, which may include spines on the shell and flanges on the aperture. Such structures have been explained as camouflage or defence, but the possibility that they might be under sexual selection has not

  4. The extracellular microenvironment explains variations in passive drug transport across different airway epithelial cell types.

    Science.gov (United States)

    Min, Kyoung Ah; Talattof, Arjang; Tsume, Yasuhiro; Stringer, Kathleen A; Yu, Jing-Yu; Lim, Dong Hyun; Rosania, Gus R

    2013-08-01

    We sought to identify key variables in cellular architecture and physiology that might explain observed differences in the passive transport properties of small molecule drugs across different airway epithelial cell types. Propranolol (PR) was selected as a weakly basic, model compound to compare the transport properties of primary (NHBE) vs. tumor-derived (Calu-3) cells. Differentiated on Transwell™ inserts, the architecture of pure vs. mixed cell co-cultures was studied with confocal microscopy followed by quantitative morphometric analysis. Cellular pharmacokinetic modeling was used to identify parameters that differentially affect PR uptake and transport across these two cell types. Pure Calu-3 and NHBE cells possessed different structural and functional properties. Nevertheless, mixed Calu-3 and NHBE cell co-cultures differentiated as stable cell monolayers. After measuring the total mass of PR, the fractional areas covered by Calu-3 and NHBE cells allowed deconvoluting the transport properties of each cell type. Based on the apparent thickness of the unstirred, cell surface aqueous layer, local differences in the extracellular microenvironment explained the measured variations in passive PR uptake and permeation between Calu-3 and NHBE cells. Mixed cell co-cultures can be used to compare the local effects of the extracellular microenvironment on drug uptake and transport across two epithelial cell types.

  5. Body mass explains characteristic scales of habitat selection in terrestrial mammals

    Science.gov (United States)

    Fisher, Jason T; Anholt, Brad; Volpe, John P

    2011-01-01

    Niche theory in its various forms is based on those environmental factors that permit species persistence, but less work has focused on defining the extent, or size, of a species’ environment: the area that explains a species’ presence at a point in space. We proposed that this habitat extent is identifiable from a characteristic scale of habitat selection, the spatial scale at which habitat best explains species’ occurrence. We hypothesized that this scale is predicted by body size. We tested this hypothesis on 12 sympatric terrestrial mammal species in the Canadian Rocky Mountains. For each species, habitat models varied across the 20 spatial scales tested. For six species, we found a characteristic scale; this scale was explained by species’ body mass in a quadratic relationship. Habitat measured at large scales best-predicted habitat selection in both large and small species, and small scales predict habitat extent in medium-sized species. The relationship between body size and habitat selection scale implies evolutionary adaptation to landscape heterogeneity as the driver of scale-dependent habitat selection. PMID:22393519

  6. Does selection bias explain the obesity paradox among individuals with cardiovascular disease?

    Science.gov (United States)

    Banack, Hailey R; Kaufman, Jay S

    2015-05-01

    The objectives of this article are to demonstrate that the obesity paradox may be explained by collider stratification bias and to estimate the biasing effects of unmeasured common causes of cardiovascular disease (CVD) and mortality on the observed obesity-mortality relationship. We use directed acyclic graphs, regression modeling, and sensitivity analyses to explore whether the observed protective effect of obesity among individuals with CVD can be plausibly attributed to selection bias. Data from the third National Health and Examination Survey was used for the analyses. The adjusted total effect of obesity on mortality was a risk difference (RD) of 0.03 (95% confidence interval [CI]: 0.02, 0.05). However, the controlled direct effect of obesity on mortality among individuals without CVD was RD = 0.03 (95% CI: 0.01, 0.05) and RD = -0.12 (95% CI: -0.20, -0.04) among individuals with CVD. The adjusted total effect estimate demonstrates an increased number of deaths among obese individuals relative to nonobese counterparts, whereas the controlled direct effect shows a paradoxical decrease in morality among obese individuals with CVD. Sensitivity analysis demonstrates unmeasured confounding of the mediator-outcome relationship provides a sufficient explanation for the observed protective effect of obesity on mortality among individuals with CVD. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Methodological development for selection of significant predictors explaining fatal road accidents.

    Science.gov (United States)

    Dadashova, Bahar; Arenas-Ramírez, Blanca; Mira-McWilliams, José; Aparicio-Izquierdo, Francisco

    2016-05-01

    Identification of the most relevant factors for explaining road accident occurrence is an important issue in road safety research, particularly for future decision-making processes in transport policy. However model selection for this particular purpose is still an ongoing research. In this paper we propose a methodological development for model selection which addresses both explanatory variable and adequate model selection issues. A variable selection procedure, TIM (two-input model) method is carried out by combining neural network design and statistical approaches. The error structure of the fitted model is assumed to follow an autoregressive process. All models are estimated using Markov Chain Monte Carlo method where the model parameters are assigned non-informative prior distributions. The final model is built using the results of the variable selection. For the application of the proposed methodology the number of fatal accidents in Spain during 2000-2011 was used. This indicator has experienced the maximum reduction internationally during the indicated years thus making it an interesting time series from a road safety policy perspective. Hence the identification of the variables that have affected this reduction is of particular interest for future decision making. The results of the variable selection process show that the selected variables are main subjects of road safety policy measures. Published by Elsevier Ltd.

  8. Improved nutrient digestibility and retention partially explains feed efficiency gains in pigs selected for low residual feed intake.

    Science.gov (United States)

    Harris, A J; Patience, J F; Lonergan, S M; J M Dekkers, C; Gabler, N K

    2012-12-01

    Residual feed intake (RFI) is a unique measure of feed efficiency (FE) and an alternative to traditional measures. The RFI is defined as the difference between the actual feed intake of a pig and its expected feed intake based on a given amount of growth and backfat. Therefore, selecting pigs with a low RFI (LRFI) results in a more feed-efficient animal for a given rate of growth. Our objective was to determine the extent to which apparent total tract digestibility of nutrients and energy use and retention may explain FE differences between pigs divergently selected for LRFI or high RFI (HRFI). After 7 generations of selection, 12 HRFI and 12 LRFI pigs (62 ± 3 kg BW) were randomly assigned to metabolism crates. Pigs had free access to a standard diet based on corn (Zea mays) and soybean (Glycine max) meal containing 0.4% TiO(2), an exogenous digestibility marker. After a 7-d acclimation, total urine and feces were collected for 72 h. Nutrient and energy digestibility, P digestibility, and N balance were then measured and calculated to determine differences between the RFI lines. As expected, ADFI was lower (2.0 vs. 2.6 kg; P energy and nutrient digestibility, use, and retention may partially explain the superior FE seen in pigs selected for LRFI.

  9. Press/Pulse: Explaining selective terrestrial extinctions at the Cretaceous/Palaeogene boundary

    Science.gov (United States)

    Arens, Nan Crystal

    2010-05-01

    Single-cause mass extinction scenarios require extreme conditions to generate sufficiently strong kill mechanisms. Such dire effects are commonly at odds with the taxonomic selectivity that characterizes most extinction events. In response, some researchers have proposed that the interaction of a variety of factors typify episodes of elevated extinction. Previous work (Arens & West 2008 Paleobiology 34:456-471) has shown that a combination of press and pulse disturbances increases the probability of elevated extinction. The press/pulse contrast is borrowed from community ecology, where researchers have long recognized that the ecological response to long-term stress differs from that of an instantaneous catastrophe. Scaled to the macroevolutionary level, press disturbances alter community composition by placing multigenerational stress on populations. Press disturbances do not necessarily cause mortality, but reduce population size by a variety of mechanisms such as curtailed reproduction. Pulse disturbances are sudden catastrophic events that cause extensive mortality. Either press or pulse disturbances of sufficient magnitude can cause extinction, however elevated extinction occurs more commonly during the coincidence of lower-magnitude press and pulse events. The Cretaceous/Palaeogene (K/P) extinction is one of the best examples of a press/pulse extinction. Deccan Trap volcanism, which straddled the K/P boundary, altered atmospheric composition and climate. This episodic volcanism likely contributed to the climate instability observed in terrestrial ecosystems and exerted press stress. Pulse disturbance was produced by bolide impact, which punctuated the end of the Cretaceous. The press/pulse mechanism also more effectively explains selectivity in terrestrial vertebrate and plant extinctions at the K/P boundary than do single-mechanisms scenarios. For example, why do environmentally sensitive vertebrates such as amphibians experience no extinction? And why do

  10. Effects of emotion regulation strategies on music elicited emotions : An experimental study explaining individual differences

    NARCIS (Netherlands)

    Karreman, A.; Laceulle, O.M.; Hanser, W.E.; Vingerhoets, A.J.J.M.

    2017-01-01

    This experimental study examined if emotional experience can be manipulated by applying an emotion regulation strategy during music listening and if individual differences in effects of strategies can be explained by person characteristics. Adults (N = 466) completed questionnaires and rated

  11. Effects of emotion regulation strategies on music-elicited emotions: An experimental study explaining individual differences

    NARCIS (Netherlands)

    Karreman, A.; Laceulle, O.M.|info:eu-repo/dai/nl/364227885; Hanser, Waldie; vingerhoets, ad

    2017-01-01

    This experimental study examined if emotional experience can be manipulated by applying an emotion regulation strategy during music listening and if individual differences in effects of strategies can be explained by person characteristics. Adults (N = 466) completed questionnaires and rated

  12. Behavioural cues surpass habitat factors in explaining prebreeding resource selection by a migratory diving duck

    Science.gov (United States)

    O'Neil, Shawn T.; Warren, Jeffrey M.; Takekawa, John Y.; De La Cruz, Susan E. W.; Cutting, Kyle A.; Parker, Michael W.; Yee, Julie L.

    2014-01-01

    Prebreeding habitat selection in birds can often be explained in part by habitat characteristics. However, females may also select habitats on the basis of fidelity to areas of previous reproductive success or use by conspecifics. The relative influences of sociobehavioural attributes versus habitat characteristics in habitat selection has been primarily investigated in songbirds, while less is known about how these factors affect habitat selection processes in migratory waterfowl. Animal resource selection models often exhibit much unexplained variation; spatial patterns driven by social and behavioural characteristics may account for some of this. We radiomarked female lesser scaup, Aythya affinis, in the southwestern extent of their breeding range to explore hypotheses regarding relative roles of habitat quality, site fidelity and conspecific density in prebreeding habitat selection. We used linear mixed-effects models to relate intensity of use within female home ranges to habitat features, distance to areas of reproductive success during the previous breeding season and conspecific density. Home range habitats included shallow water (≤118 cm), moderate to high densities of flooded emergent vegetation/open water edge and open water areas with submerged aquatic vegetation. Compared with habitat features, conspecific female density and proximity to successful nesting habitats from the previous breeding season had greater influences on habitat use within home ranges. Fidelity and conspecific attraction are behavioural characteristics in some waterfowl species that may exert a greater influence than habitat features in influencing prebreeding space use and habitat selection within home ranges, particularly where quality habitat is abundant. These processes may be of critical importance to a better understanding of habitat selection in breeding birds.

  13. Like two peas in a pod? Explaining friendship selection processes related to victimization and offending

    NARCIS (Netherlands)

    Rokven, Josja J.; Tolsma, Jochem; Ruiter, Stijn; Kraaykamp, Gerbert

    2016-01-01

    In this paper, we examine the similarity between friends with respect to experiences with crime among a sample of Dutch individuals. We investigate the extent to which offenders, victims and victim-offenders (de)select friends differently and, subsequently, who (de)selects whom and why. We use data

  14. Heat loss may explain bill size differences between birds occupying different habitats.

    Directory of Open Access Journals (Sweden)

    Russell Greenberg

    Full Text Available BACKGROUND: Research on variation in bill morphology has focused on the role of diet. Bills have other functions, however, including a role in heat and water balance. The role of the bill in heat loss may be particularly important in birds where water is limiting. Song sparrows localized in coastal dunes and salt marsh edge (Melospiza melodia atlantica are similar in size to, but have bills with a 17% greater surface area than, those that live in mesic habitats (M. m. melodia, a pattern shared with other coastal sparrows. We tested the hypotheses that sparrows can use their bills to dissipate "dry" heat, and that heat loss from the bill is higher in M. m. atlantica than M. m. melodia, which would indicate a role of heat loss and water conservation in selection for bill size. METHODOLOGY/PRINCIPAL FINDINGS: Bill, tarsus, and body surface temperatures were measured using thermal imaging of sparrows exposed to temperatures from 15-37°C and combined with surface area and physical modeling to estimate the contribution of each body part to total heat loss. Song sparrow bills averaged 5-10°C hotter than ambient. The bill of M. m atlantica dissipated up to 33% more heat and 38% greater proportion of total heat than that of M. m. melodia. This could potentially reduce water loss requirements by approximately 7.7%. CONCLUSIONS/SIGNIFICANCE: This >30% higher heat loss in the bill of M. m. atlantica is independent of evaporative water loss and thus could play an important role in the water balance of sparrows occupying the hot and exposed dune/salt marsh environments during the summer. Heat loss capacity and water conservation could play an important role in the selection for bill size differences between bird populations and should be considered along with trophic adaptations when studying variation in bill size.

  15. Cognitive Abilities, Monitoring Confidence, and Control Thresholds Explain Individual Differences in Heuristics and Biases

    OpenAIRE

    Jackson, Simon A.; Kleitman, Sabina; Howie, Pauline; Stankov, Lazar

    2016-01-01

    In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence, and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgments, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing tha...

  16. Cognitive abilities, monitoring, and control explain individual differences in heuristics and biases

    OpenAIRE

    Simon Anthony Jackson; Sabina Kleitman; Pauline Howie; Lazar Stankov

    2016-01-01

    In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgements, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing tha...

  17. Explaining international differences in male skill wage differentials by differences in demand and supply of skill

    NARCIS (Netherlands)

    Leuven, E.; Oosterbeek, H.; van Ophem, H.

    2004-01-01

    This paper explores the hypothesis that wage differentials between skill groups across countries are consistent with a demand and supply framework. Using micro data from 15 countries we find that about one third of the variation in relative wages between skill groups across countries is explained by

  18. Testing Stereotype Threat: Does Anxiety Explain Race and Sex Differences in Achievement?

    Science.gov (United States)

    Osborne, Jason W.

    2001-07-01

    Steele's (1992, 1997) stereotype-threat theory attempts to explain underperformance of minority students in academic domains and of women in mathematics. Steele argues that situational self-relevance of negative group stereotypes in testing situations increases the anxiety these students experience and that these differential anxiety levels explain performance differences. Research shows that manipulation of stereotype threat can affect academic performance. However, there has been little research testing whether anxiety does at least partially explain the relationship between race and achievement. The goal of this study was to examine whether anxiety will explain racial differences in academic performance and gender differences in math performance in the context of a nationally representative sample of high school seniors. Partial mediation was observed, with anxiety explaining significant portions of the racial differences in academic performance. Anxiety also partially explained sex differences in math achievement, although the effect sizes were very small. These results provide general support for Steele's stereotype-threat hypothesis. Copyright 2001 Academic Press.

  19. Simulating the Cinema Market : How cross-cultural differences in social influence explain box office distributions

    NARCIS (Netherlands)

    Broekhuizen, T.L.J.; Delre, S.A.; Torres, A.

    This paper uses a mixed method approach to show how cross-cultural differences in social influences can explain differences in distributions of market shares in different markets. First, we develop a realistic agent-based model that mimics the behavior of movie visitors and incorporates the social

  20. Peers and delinquency among girls and boys: are sex differences in delinquency explained by peer factors?

    NARCIS (Netherlands)

    Weerman, F.M.; Hoeve, M.

    2012-01-01

    In this article, we investigate sex differences in the relationship between peers and delinquency. We analyse to what extent peers have different effects on delinquency among girls and boys, and to what extent sex differences in the level of delinquency can be explained by differential exposure or

  1. Explaining Cross-Country Differences in Attitudes towards Immigration in the EU-15

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Munch, Jakob Roland; Schroll, Sanne

    2007-01-01

    In this paper, we use data from the first two rounds of the European Social Survey to analyze the extent to which differences in average attitudes towards immigration across the EU-15 countries may be explained by differences in socioeconomic characteristics and individually perceived consequences...... of immigration, using an extension of a decomposition technique developed by Fairlie (2005). We find that despite the significant effects of socioeconomic characteristics on attitudes, differences in the distributions of these characteristics can only explain a modest share of the cross-country variation...... in average attitudes. A larger part can be explained by differences in perceived consequences of immigration, but the main part is still left unexplained. Apart from providing useful input for policy makers working in the area of immigration policy, this raises a number of questions for further research...

  2. Explaining Cross-Country Differences in Attitudes Towards Immigration in the EU-15

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Munch, Jakob Roland; Skaksen, Jan Rose

    In this paper, we use data from the first two rounds of the European Social Survey to analyse the extent to which differences in average attitudes towards immigration across the EU-15 countries may be explained by differences in socioeconomic characteristics and individually perceived consequences...... of immigration, using an extension of a decomposition technique developed by Fairlie (2005). We find that despite the significant effects of socioeconomic characteristics on attitudes, differences in the distributions of these characteristics can only explain a modest share of the cross-country variation...... in average attitudes. A larger part can be explained by differences in perceived consequences of immigration, but the main part is still left unexplained. Apart from providing useful input for policy makers working in the area of immigration policy, this raises a number of questions for further research...

  3. Explaining Cross-Country Differences in Attitudes Towards Immigration in the EU-15

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Munch, Jakob Roland; Schroll, Sanne

    2009-01-01

    In this paper, we use data from the first two rounds of the European Social Survey to analyze the extent to which differences in average attitudes towards immigration across the EU-15 countries may be explained by differences in socioeconomic characteristics and individually perceived consequences...... of immigration, using an extension of a decomposition technique developed by Fairlie (2005). We find that despite the significant effects of socioeconomic characteristics on attitudes, differences in the distributions of these characteristics can only explain a modest share of the cross-country variation...... in average attitudes. A larger part can be explained by differences in perceived consequences of immigration, but the main part is still left unexplained. Apart from providing useful input for policy makers working in the area of immigration policy, this raises a number of questions for further research...

  4. Population Differences at MHC Do Not Explain Enhanced Resistance of Song Sparrows to Local Parasites.

    Science.gov (United States)

    Slade, Joel W G; Sarquis-Adamson, Yanina; Gloor, Gregory B; Lachance, Marc-André; MacDougall-Shackleton, Elizabeth A

    2017-03-01

    Infectious disease represents an emerging threat to natural populations, particularly when hosts are more susceptible to novel parasites (allopatric) than to parasites from the local area (sympatric). This pattern could arise through evolutionary processes (host populations become adapted to their local parasites and genetically differentiated from other populations at immune-related loci) and/or through ecological interactions (host individuals develop resistance to local parasites through previous exposure). The relative importance of these candidate mechanisms remains unclear. In jawed vertebrates, genes of the major histocompatibility complex (MHC) play a fundamental role in immunity and are compelling candidates for spatially varying selection. We recently showed that song sparrows (Melospiza melodia) are more susceptible to allopatric than to sympatric strains of malaria (Plasmodium). In the current study, to determine whether population differences at MHC explain this pattern, we characterized the peptide-binding regions of MHC (classes I and II) of birds that did or did not become infected in the previous experiment. We recovered up to 4 alleles per individual at class I, implying at least 2 loci, and up to 26 alleles per individual at class II, implying at least 13 loci. Individuals with more class I alleles were less likely to become infected by Plasmodium, consistent with parasite-mediated balancing selection. However, we found no evidence for population genetic differentiation at either class of MHC, based on 36 individuals sequenced. Resistance to sympatric parasites previously described for this system likely stems from individuals' prior immune experience, not from population differentiation and locally protective alleles at MHC. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Explaining sex differences in chronic musculoskeletal pain in a general population

    NARCIS (Netherlands)

    Wijnhoven, Hanneke A H; de Vet, Henrica C W; Picavet, H. Susan J

    Many studies report a female predominance in the prevalence of chronic musculoskeletal pain (CMP) but the mechanisms explaining these sex differences are poorly understood. Data from a random postal questionnaire survey in the Dutch general population were used to examine whether sex differences in

  6. Explaining sex differences in chronic musculoskeletal pain in a general population.

    NARCIS (Netherlands)

    Wijnhoven, Hanneke A H; Vet, Henrica C W de; Picavet, H Susan J

    2006-01-01

    Many studies report a female predominance in the prevalence of chronic musculoskeletal pain (CMP) but the mechanisms explaining these sex differences are poorly understood. Data from a random postal questionnaire survey in the Dutch general population were used to examine whether sex differences in

  7. Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe?

    NARCIS (Netherlands)

    Deschepper, Reginald; Grigoryan, Larissa; Lundborg, Cecilia Stalsby; Hofstede, Geert; Cohen, Joachim; Van Der Kelen, Greta; Deliens, Luc; Haaijer-Ruskamp, Flora M.

    2008-01-01

    Background: Antibiotics are widely-used medicines for which a more prudent use has been advocated to minimize development of resistance. There are considerable cross-national differences that can only partially be explained by epidemiological difference and variations in health care structure. The

  8. Do Differences in Childhood Diet Explain the Reduced Overweight Risk in Breastfed Children?

    NARCIS (Netherlands)

    Scholtens, Salome; Brunekreef, Bert; Smit, Henriette A.; Gast, Gerrie-Cor M.; Hoekstra, Maarten O.; De Jongste, Johan C.; Postma, Dirkje S.; Gerritsen, Jorrit; Seidell, Jaap C.; Wijga, Alet H.

    2008-01-01

    Breastfeeding has been associated with a reduced risk of overweight later in life. This study investigates whether differences in diet and lifestyle at 7 years of age between breastfed and formula-fed children can explain the difference in overweight prevalence at 8 years of age. We studied 2,043

  9. The attribution of work environment in explaining gender differences in long-term sickness absence

    DEFF Research Database (Denmark)

    Labriola, Merete; Holte, Kari Anne; Christensen, Karl Bang

    2011-01-01

    40.2 years) was interviewed in 2000 regarding gender, age, family status, socio-economic position and psychosocial and physical work environment factors. The participants were followed for 18 months in order to assess their incidence of long-term sickness absence exceeding 8 consecutive weeks...... in psychosocial work environment exposures explained 32% of the differences in risk of long-term sickness absence between men and women, causing the effect of gender to become statistically insignificant. The combined effect of physical and psychosocial factors was similar, explaining 30% of the gender difference....... Conclusion Differences in psychosocial work environments in terms of emotional demands, reward at work, management quality and role conflicts, explained roughly 30% of women's excess long-term sickness absence risk. Assuming women and men had identical working conditions would leave the larger part...

  10. Can Xanthophyll-Membrane Interactions Explain Their Selective Presence in the Retina and Brain?

    Directory of Open Access Journals (Sweden)

    Justyna Widomska

    2016-01-01

    Full Text Available Epidemiological studies demonstrate that a high dietary intake of carotenoids may offer protection against age-related macular degeneration, cancer and cardiovascular and neurodegenerative diseases. Humans cannot synthesize carotenoids and depend on their dietary intake. Major carotenoids that have been found in human plasma can be divided into two groups, carotenes (nonpolar molecules, such as β-carotene, α-carotene or lycopene and xanthophylls (polar carotenoids that include an oxygen atom in their structure, such as lutein, zeaxanthin and β-cryptoxanthin. Only two dietary carotenoids, namely lutein and zeaxanthin (macular xanthophylls, are selectively accumulated in the human retina. A third carotenoid, meso-zeaxanthin, is formed directly in the human retina from lutein. Additionally, xanthophylls account for about 70% of total carotenoids in all brain regions. Some specific properties of these polar carotenoids must explain why they, among other available carotenoids, were selected during evolution to protect the retina and brain. It is also likely that the selective uptake and deposition of macular xanthophylls in the retina and brain are enhanced by specific xanthophyll-binding proteins. We hypothesize that the high membrane solubility and preferential transmembrane orientation of macular xanthophylls distinguish them from other dietary carotenoids, enhance their chemical and physical stability in retina and brain membranes and maximize their protective action in these organs. Most importantly, xanthophylls are selectively concentrated in the most vulnerable regions of lipid bilayer membranes enriched in polyunsaturated lipids. This localization is ideal if macular xanthophylls are to act as lipid-soluble antioxidants, which is the most accepted mechanism through which lutein and zeaxanthin protect neural tissue against degenerative diseases.

  11. Does selection or genetic drift explain geographic differentiation of morphological characters in house sparrows Passer domesticus?

    Science.gov (United States)

    Holand, Anna M; Jensen, Henrik; Tufto, Jarle; Moe, Rune

    2011-10-01

    Understanding the relative influence of genetic drift and selection is fundamental in evolutionary biology. The theory of neutrality predicts that the genetic differentiation of a quantitative trait (QST) equals the genetic differentiation at neutral molecular markers (FST) if the quantitative trait has not been under selection. Thus, the relative magnitude of observed QST and expected QST under neutral expectations suggests the importance of selection and genetic drift for any observed phenotypic divergence. Because QST is based on additive genetic variance, estimating QST based on phenotypic measurements is problematic due to unknown environmental effects. To account for this, we used a model where the environmental component was allowed to vary when estimating QST. The model was used on data from 14 house sparrow (Passer domesticus) populations in Norway. In accordance with the significant phenotypic inter-population differences our analyses suggested that directional selection may have favoured different optimal phenotypes for some morphological traits across populations. In particular, different body mass and male ornamental phenotypes seemed to have been favoured. The conclusions are, however, dependent on assumptions regarding the proportion of the observed inter-population variation that is due to additive genetic differences, showing the importance of collecting such information in natural populations. By estimating QST, allowing the additive genetic proportion of phenotypic inter-population variation to vary, and by making use of recent statistical methods to compare observed QST with neutral expectations, we can use data that are relatively easy to collect to identify adaptive variation in natural populations.

  12. Distinct roles of left inferior frontal regions that explain individual differences in second language acquisition.

    Science.gov (United States)

    Sakai, Kuniyoshi L; Nauchi, Arihito; Tatsuno, Yoshinori; Hirano, Kazuyoshi; Muraishi, Yukimasa; Kimura, Masakazu; Bostwick, Mike; Yusa, Noriaki

    2009-08-01

    Second language (L2) acquisition is more susceptible to environmental and idiosyncratic factors than first language acquisition. Here, we used functional magnetic resonance imaging for L2 learners of different ages of first exposure (mean: 12.6 and 5.6 years) in a formal school environment, and compared the cortical activations involved in processing English sentences containing either syntactic or spelling errors, where the testing ages and task performances of both groups were matched. We found novel activation patterns in two regions of the left inferior frontal gyrus (IFG) that correlated differentially with the performances of the late and early learners. Specifically, activations of the dorsal and ventral triangular part (F3t) of the left IFG correlated positively with the accuracy of the syntactic task for the late learners, whereas activations of the left ventral F3t correlated negatively with the accuracy for the early learners. In contrast, other cortical regions exhibited differential correlation patterns with the reaction times (RTs) of the syntactic task. Namely, activations of the orbital part (F3O) of the left IFG, as well as those of the left angular gyrus, correlated positively with the RTs for the late learners, whereas those activations correlated negatively with the RTs for the early learners. Moreover, the task-selective activation of the left F3O was maintained for both the late and early learners. These results explain individual differences in L2 acquisition, such that the acquisition of linguistic knowledge in L2 is subserved by at least two distinct inferior frontal regions of the left F3t and F3O. (c) 2008 Wiley-Liss, Inc.

  13. Availability, diversification and versatility explain human selection of introduced plants in Ecuadorian traditional medicine

    Science.gov (United States)

    Gaoue, Orou G.; de la Torre, Lucía; Navarrete, Hugo; Muriel, Priscilla; Macía, Manuel J.; Balslev, Henrik; León-Yánez, Susana; Jørgensen, Peter; Duffy, David Cameron

    2017-01-01

    Globally, a majority of people use plants as a primary source of healthcare and introduced plants are increasingly discussed as medicine. Protecting this resource for human health depends upon understanding which plants are used and how use patterns will change over time. The increasing use of introduced plants in local pharmacopoeia has been explained by their greater abundance or accessibility (availability hypothesis), their ability to cure medical conditions that are not treated by native plants (diversification hypothesis), or as a result of the introduced plants’ having many different simultaneous roles (versatility hypothesis). In order to describe the role of introduced plants in Ecuador, and to test these three hypotheses, we asked if introduced plants are over-represented in the Ecuadorian pharmacopoeia, and if their use as medicine is best explained by the introduced plants’ greater availability, different therapeutic applications, or greater number of use categories. Drawing on 44,585 plant-use entries, and the checklist of >17,000 species found in Ecuador, we used multi-model inference to test if more introduced plants are used as medicines in Ecuador than expected by chance, and examine the support for each of the three hypotheses above. We find nuanced support for all hypotheses. More introduced plants are utilized than would be expected by chance, which can be explained by geographic distribution, their strong association with cultivation, diversification (except with regard to introduced diseases), and therapeutic versatility, but not versatility of use categories. Introduced plants make a disproportionately high contribution to plant medicine in Ecuador. The strong association of cultivation with introduced medicinal plant use highlights the importance of the maintenance of human-mediated environments such as homegardens and agroforests for the provisioning of healthcare services. PMID:28886104

  14. Differences in early gesture explain SES disparities in child vocabulary size at school entry.

    Science.gov (United States)

    Rowe, Meredith L; Goldin-Meadow, Susan

    2009-02-13

    Children from low-socioeconomic status (SES) families, on average, arrive at school with smaller vocabularies than children from high-SES families. In an effort to identify precursors to, and possible remedies for, this inequality, we videotaped 50 children from families with a range of different SES interacting with parents at 14 months and assessed their vocabulary skills at 54 months. We found that children from high-SES families frequently used gesture to communicate at 14 months, a relation that was explained by parent gesture use (with speech controlled). In turn, the fact that children from high-SES families have large vocabularies at 54 months was explained by children's gesture use at 14 months. Thus, differences in early gesture help to explain the disparities in vocabulary that children bring with them to school.

  15. Can dietary factors explain differences in serum cholesterol profiles among different ethnic groups (Chinese, Malays and Indians) in Singapore?

    NARCIS (Netherlands)

    Deurenberg-Yap, M.; Li, T.; Tan, W.L.; Staveren, van W.A.; Suok Chai Chew,; Deurenberg, P.

    2001-01-01

    In Singapore. there exists differences in risk factors for coronary heart disease among the three main ethnic groups: Chinese, Malays and Indians. This study aimed to investigate if differences in dietary intakes of fat, types of fat, cholesterol, fruits, vegetables and grain foods could explain the

  16. Explaining the Difference between PISA 2009 Reading Scores in Finland and Estonia

    Science.gov (United States)

    Mikk, Jaan

    2015-01-01

    The aim of the study was to explain the difference between the Programme for International Student Assessment (PISA) 2009 reading results for Finland and Estonia using characteristics of teaching and learning, and characteristics of the overall development of these countries. PISA data were collected via a reading test and student questionnaires…

  17. Explaining socio-demographic differences in disengagement from sports in adolescence

    NARCIS (Netherlands)

    Prins, R.G.; Kamphuis, C.B.M.; Empelen, P. van; Beenackers, M.A.; Brug, J.; Mackenbach, J.P.; Oenema, A.

    2013-01-01

    Purpose: The purpose of this longitudinal study is to identify risk groups for disengagement from sports during adolescence. In addition, it will be explored whether cognitive and environmental factors can explain socio-demographic differences in disengagement from sports. METHODS: Data were

  18. Complex and changing patterns of natural selection explain the evolution of the human hip.

    Science.gov (United States)

    Grabowski, Mark; Roseman, Charles C

    2015-08-01

    Causal explanations for the dramatic changes that occurred during the evolution of the human hip focus largely on selection for bipedal function and locomotor efficiency. These hypotheses rest on two critical assumptions. The first-that these anatomical changes served functional roles in bipedalism-has been supported in numerous analyses showing how postcranial changes likely affected locomotion. The second-that morphological changes that did play functional roles in bipedalism were the result of selection for that behavior-has not been previously explored and represents a major gap in our understanding of hominin hip evolution. Here we use evolutionary quantitative genetic models to test the hypothesis that strong directional selection on many individual aspects of morphology was responsible for the large differences observed across a sample of fossil hominin hips spanning the Plio-Pleistocene. Our approach uses covariance among traits and the differences between relatively complete fossils to estimate the net selection pressures that drove the major transitions in hominin hip evolution. Our findings show a complex and changing pattern of natural selection drove hominin hip evolution, and that many, but not all, traits hypothesized to play functional roles in bipedalism evolved as a direct result of natural selection. While the rate of evolutionary change for all transitions explored here does not exceed the amount expected if evolution was occurring solely through neutral processes, it was far above rates of evolution for morphological traits in other mammalian groups. Given that stasis is the norm in the mammalian fossil record, our results suggest that large shifts in the adaptive landscape drove hominin evolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. New evidence for positive selection helps explain the paternal age effect observed in achondroplasia

    Science.gov (United States)

    Shinde, Deepali N.; Elmer, Dominik P.; Calabrese, Peter; Boulanger, Jérôme; Arnheim, Norman; Tiemann-Boege, Irene

    2013-01-01

    There are certain de novo germline mutations associated with genetic disorders whose mutation rates per generation are orders of magnitude higher than the genome average. Moreover, these mutations occur exclusively in the male germ line and older men have a higher probability of having an affected child than younger ones, known as the paternal age effect (PAE). The classic example of a genetic disorder exhibiting a PAE is achondroplasia, caused predominantly by a single-nucleotide substitution (c.1138G>A) in FGFR3. To elucidate what mechanisms might be driving the high frequency of this mutation in the male germline, we examined the spatial distribution of the c.1138G>A substitution in a testis from an 80-year-old unaffected man. Using a technology based on bead-emulsion amplification, we were able to measure mutation frequencies in 192 individual pieces of the dissected testis with a false-positive rate lower than 2.7 × 10−6. We observed that most mutations are clustered in a few pieces with 95% of all mutations occurring in 27% of the total testis. Using computational simulations, we rejected the model proposing an elevated mutation rate per cell division at this nucleotide site. Instead, we determined that the observed mutation distribution fits a germline selection model, where mutant spermatogonial stem cells have a proliferative advantage over unmutated cells. Combined with data on several other PAE mutations, our results support the idea that the PAE, associated with a number of Mendelian disorders, may be explained primarily by a selective mechanism. PMID:23740942

  20. Treatment for depression in 63 countries worldwide: describing and explaining cross-national differences.

    Science.gov (United States)

    Smits, Fransje; Huijts, Tim

    2015-01-01

    This study describes differences between 63 countries in treatment for depression and explores explanations for these differences. Treatment for depression is measured as the overall chance that an individual receives treatment, plus as the chance to receive treatment given the presence of depressive symptoms. Using the World Health Survey (2002-2004, N=249,116), we find strong cross-national variation in the chance to receive treatment for depression. Additionally, multilevel regression analyses reveal that urbanization, employment status, marital status, level of education, gender, age, and national wealth all partly explain cross-national differences in the chance to receive treatment for depression. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Can differences in obstetric outcomes be explained by differences in the care provided? The MFMU Network APEX study.

    Science.gov (United States)

    Grobman, William A; Bailit, Jennifer L; Rice, Madeline Murguia; Wapner, Ronald J; Varner, Michael W; Thorp, John M; Leveno, Kenneth J; Caritis, Steve N; Iams, Jay D; Tita, Alan T; Saade, George; Sorokin, Yoram; Rouse, Dwight J; Tolosa, Jorge E; Van Dorsten, J Peter

    2014-08-01

    The purpose of this study was to determine whether hospital differences in the frequency of adverse obstetric outcomes are related to differences in care. The Assessment of Perinatal EXcellence cohort comprises 115,502 women and their neonates who were born in 25 hospitals in the United States between March 2008 and February 2011. Hierarchical logistic regression was used to quantify the amount of variation in postpartum hemorrhage, peripartum infection, severe perineal laceration, and a composite adverse neonatal outcome among hospitals that is explained by differences in patient characteristics, hospital characteristics, and obstetric care provided. The study included 115,502 women. For most outcomes, 20-40% of hospital differences in outcomes were related to differences in patient populations. After adjusting for patient-, provider-, and hospital-level factors, multiple care processes were associated with the predefined adverse outcomes; however, these care processes did not explain significant variation in the frequency of adverse outcomes among hospitals. Ultimately, 50-100% of the interhospital variation in outcomes was unexplained. Hospital differences in the frequency of adverse obstetric outcomes could not be explained by differences in frequency of types of care provided. Copyright © 2014 Mosby, Inc. All rights reserved.

  2. The relative importance of individual, job-related and organisational characteristics in explaining differences in earnings.

    OpenAIRE

    Sels, Luc; Overlaet, Robrecht; Welkenhuysen-Gybels, J; Gevers, A.

    2000-01-01

    Abstract: This paper focuses on a number of key research questions: (1) What is the relative importance of individual, job-related and organizational characteristics in explaining differences in earnings? (2) Do job characteristics such as hierarchical level and functional domain exercise a significant influence on pay differentials if we control for the traditional human capital factors? (3) Do organizational characteristics such as size and the sector in which the company is active exercise...

  3. Sex Differences in Gray Matter Volume of the Right Anterior Hippocampus Explain Sex Differences in Three-Dimensional Mental Rotation

    OpenAIRE

    Wei, Wei; Chen, Chuansheng; Dong, Qi; Zhou, Xinlin

    2016-01-01

    Behavioral studies have reported that males perform better than females in 3-dimensional (3D) mental rotation. Given the important role of the hippocampus in spatial processing, the present study investigated whether structural differences in the hippocampus could explain the sex difference in 3D mental rotation. Results showed that after controlling for brain size, males had a larger anterior hippocampus, whereas females had a larger posterior hippocampus. Gray matter volume (GMV) of the rig...

  4. Why factors rooted in the family may solely explain the urban-rural differences in schizophrenia risk estimates

    DEFF Research Database (Denmark)

    Pedersen, Carsten Bøcker; Mortensen, Preben Bo

    2006-01-01

    explain the urban-rural differences. Although other potential explanations for these differences exist, we focus on this hypothesis as it has not previously been discussed in detail. To determine the cause(s) responsible for the urban-rural differences, we need direct measurements of genetic and......Many studies have identified urban-rural differences in schizophrenia risk. The underlying cause(s) may hypothetically include toxic exposures, diet, infections, and selective migration. In a recent study, we concluded that some of the cause(s) responsible for the urban-rural differences...... in schizophrenia risk are rooted in families, but some might also be rooted in individuals. First, we describe temporality as a potential methodological pitfall within this line of research, then we review studies not subject to this pitfall, and finally, we describe why factors rooted in the family may solely...

  5. Musculoskeletal simulation can help explain selective muscle degeneration in Duchenne muscular dystrophy.

    Science.gov (United States)

    Hu, Xiao; Blemker, Silvia S

    2015-08-01

    Duchenne muscular dystrophy (DMD) is a genetic disease that occurs due to the deficiency of the dystrophin protein. Although dystrophin is deficient in all muscles, it is unclear why degeneration progresses differently across muscles in DMD. We hypothesized that each muscle undergoes a different degree of eccentric contraction during gait, which could contribute to the selective degeneration in lower limb muscle, as indicated by various amounts of fatty infiltration. By comparing eccentric contractions quantified from a previous multibody dynamic musculoskeletal gait simulation and fat fractions quantified in a recent imaging study, our preliminary analyses show a strong correlation between eccentric contractions during gait and lower limb muscle fat fractions, supporting our hypothesis. This knowledge is critical for developing safe exercise regimens for the DMD population. This study also provides supportive evidence for using multiscale modeling and simulation of the musculoskeletal system in future DMD research. © 2015 Wiley Periodicals, Inc.

  6. The coexistence of acorns with different maturation patterns explains acorn production variability in cork oak.

    Science.gov (United States)

    Pons, Josep; Pausas, Juli G

    2012-07-01

    In dry areas such as Mediterranean ecosystems, fluctuations in seed production are typically explained by resource (water) availability. However, acorn production in cork oak (Quercus suber) populations shows a very low relationship to weather. Because cork oak trees produce acorns with different maturation patterns (annual and biennial), we hypothesized that acorn production in coexisting individuals with a different dominant acorn maturation type should respond differently to climatic factors and that disaggregating the trees according to their acorn-maturation pattern should provide a more proximal relation to weather factors. We assessed acorn production variability in fragmented cork oak populations of the eastern Iberian Peninsula by counting the total number of acorns in 155 trees during an 8-year period. An initial assessment of acorn production variability in relation to weather parameters yielded very low explained variance (7%). However, after the trees were grouped according to their dominant acorn maturation pattern, weather parameters were found to account for 44% of the variability in acorn crops, with trees with annual acorns exhibiting mast fruiting in years with reduced spring frost and shorter summer droughts and trees with biennial acorns showing the opposite pattern. Thus, conditions that negatively affect annual production could be beneficial for biennial production (and vice versa). The results highlight the importance of the resource-matching hypothesis for explaining acorn production in Quercus suber and suggest that different seed maturation types within a population may allow the species to deal with highly variable weather conditions. They also emphasize the importance of understanding acorn maturation patterns for interpreting masting cycles.

  7. A Model of How Different Biology Experts Explain Molecular and Cellular Mechanisms

    Science.gov (United States)

    Trujillo, Caleb M.; Anderson, Trevor R.; Pelaez, Nancy J.

    2015-01-01

    Constructing explanations is an essential skill for all science learners. The goal of this project was to model the key components of expert explanation of molecular and cellular mechanisms. As such, we asked: What is an appropriate model of the components of explanation used by biology experts to explain molecular and cellular mechanisms? Do explanations made by experts from different biology subdisciplines at a university support the validity of this model? Guided by the modeling framework of R. S. Justi and J. K. Gilbert, the validity of an initial model was tested by asking seven biologists to explain a molecular mechanism of their choice. Data were collected from interviews, artifacts, and drawings, and then subjected to thematic analysis. We found that biologists explained the specific activities and organization of entities of the mechanism. In addition, they contextualized explanations according to their biological and social significance; integrated explanations with methods, instruments, and measurements; and used analogies and narrated stories. The derived methods, analogies, context, and how themes informed the development of our final MACH model of mechanistic explanations. Future research will test the potential of the MACH model as a guiding framework for instruction to enhance the quality of student explanations. PMID:25999313

  8. How much of the difference in life expectancy between Scottish cities does deprivation explain?

    Science.gov (United States)

    Seaman, R; Mitchell, R; Dundas, R; Leyland, A H; Popham, F

    2015-10-16

    Glasgow's low life expectancy and high levels of deprivation are well documented. Studies comparing Glasgow to similarly deprived cities in England suggest an excess of deaths in Glasgow that cannot be accounted for by deprivation. Within Scotland comparisons are more equivocal suggesting deprivation could explain Glasgow's excess mortality. Few studies have used life expectancy, an intuitive measure that quantifies the between-city difference in years. This study aimed to use the most up-to-date data to compare Glasgow to other Scottish cities and to (i) evaluate whether deprivation could account for lower life expectancy in Glasgow and (ii) explore whether the age distribution of mortality in Glasgow could explain its lower life expectancy. Sex specific life expectancy was calculated for 2007-2011 for the population in Glasgow and the combined population of Aberdeen, Dundee and Edinburgh. Life expectancy was calculated for deciles of income deprivation, based on the national ranking of datazones, using the Scottish Index of Multiple Deprivation. Life expectancy in Glasgow overall, and by deprivation decile, was compared to that in Aberdeen, Dundee and Edinburgh combined, and the life expectancy difference decomposed by age using Arriaga's discrete method. Life expectancy for the whole Glasgow population was lower than the population of Aberdeen, Dundee and Edinburgh combined. When life expectancy was compared by national income deprivation decile, Glasgow's life expectancy was not systematically lower, and deprivation accounted for over 90 % of the difference. This was reduced to 70 % of the difference when carrying out sensitivity analysis using city-specific income deprivation deciles. In both analyses life expectancy was not systematically lower in Glasgow when stratified by deprivation. Decomposing the differences in life expectancy also showed that the age distribution of mortality was not systematically different in Glasgow after accounting for deprivation

  9. Differences in energy expenditures and growth dilution explain higher PCB concentrations in male summer flounder

    Science.gov (United States)

    Madenjian, Charles P.; Jensen, Olaf P.; Rediske, Richard R.; O'Keefe, James P.; Vastano, Anthony R.; Pothoven, Steven A.

    2016-01-01

    Comparison of polychlorinated biphenyl (PCB) concentrations between the sexes of mature fish may reveal important behavioral and physiological differences between the sexes. We determined whole-fish PCB concentrations in 23 female summer flounder Paralichthys dentatus and 27 male summer flounder from New Jersey coastal waters. To investigate the potential for differences in diet or habitat utilization between the sexes, carbon and nitrogen stable isotope ratios were also determined. In 5 of the 23 female summer flounder, PCB concentrations in the somatic tissue and ovaries were determined. In addition, we used bioenergetics modeling to assess the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 87 and 124 ng/g, respectively; thus males were 43% higher in PCB concentration compared with females. Carbon and nitrogen stable isotope ratios did not significantly differ between the sexes, suggesting that diet composition and habitat utilization did not vary between the sexes. Based on PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 0.6%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain the higher PCB concentrations observed in males. Bioenergetics modeling results indicated that the growth dilution effect could account for males being 19% higher in PCB concentration compared with females. Thus, the bulk of the observed difference in PCB concentrations between the sexes was not explained by growth dilution. We concluded that a higher rate of energy expenditure in males, stemming from greater activity and a greater resting metabolic rate, was most likely the primary driver for the observed difference in PCB concentrations between the sexes.

  10. Differences in Energy Expenditures and Growth Dilution Explain Higher PCB Concentrations in Male Summer Flounder.

    Directory of Open Access Journals (Sweden)

    Charles P Madenjian

    Full Text Available Comparison of polychlorinated biphenyl (PCB concentrations between the sexes of mature fish may reveal important behavioral and physiological differences between the sexes. We determined whole-fish PCB concentrations in 23 female summer flounder Paralichthys dentatus and 27 male summer flounder from New Jersey coastal waters. To investigate the potential for differences in diet or habitat utilization between the sexes, carbon and nitrogen stable isotope ratios were also determined. In 5 of the 23 female summer flounder, PCB concentrations in the somatic tissue and ovaries were determined. In addition, we used bioenergetics modeling to assess the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 87 and 124 ng/g, respectively; thus males were 43% higher in PCB concentration compared with females. Carbon and nitrogen stable isotope ratios did not significantly differ between the sexes, suggesting that diet composition and habitat utilization did not vary between the sexes. Based on PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 0.6%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain the higher PCB concentrations observed in males. Bioenergetics modeling results indicated that the growth dilution effect could account for males being 19% higher in PCB concentration compared with females. Thus, the bulk of the observed difference in PCB concentrations between the sexes was not explained by growth dilution. We concluded that a higher rate of energy expenditure in males, stemming from greater activity and a greater resting metabolic rate, was most likely the primary driver for the observed difference in PCB concentrations between the sexes.

  11. Explaining black-white differences in receipt of recommended colon cancer treatment.

    Science.gov (United States)

    Baldwin, Laura-Mae; Dobie, Sharon A; Billingsley, Kevin; Cai, Yong; Wright, George E; Dominitz, Jason A; Barlow, William; Warren, Joan L; Taplin, Stephen H

    2005-08-17

    Black-white disparities exist in receipt of recommended medical care, including colorectal cancer treatment. This retrospective cohort study examines the degree to which health systems (e.g., physician, hospital) factors explain black-white disparities in colon cancer care. Data from the Surveillance, Epidemiology, and End Results program; Medicare claims; the American Medical Association Masterfile; and hospital surveys were linked to examine chemotherapy receipt after stage III colon cancer resection among 5294 elderly (> or = 66 years of age) black and white Medicare-insured patients. Logistic regression analysis was used to identify factors associated with black-white differences in chemotherapy use. All statistical tests were two-sided. Black and white patients were equally likely to consult with a medical oncologist, but among patients who had such a consultation, black patients were less likely than white patients (59.3% versus 70.4%, difference = 10.9%, 95% confidence interval [CI] = 5.1% to 16.4%, P statistically significant in the regression analysis. Overall, patient, physician, hospital, and environmental factors accounted for approximately 50% of the disparity in chemotherapy receipt among patients aged 66-70 years; surgical length of stay and neighborhood socioeconomic status accounted for approximately 27% of the disparity in this age group, and health systems factors accounted for 12%. Black and white Medicare-insured colon cancer patients have an equal opportunity to learn about adjuvant chemotherapy from a medical oncologist but do not receive chemotherapy equally. Little disparity was explained by health systems; more was explained by illness severity, social support, and environment. Further qualitative research is needed to understand the factors that influence the lower receipt of chemotherapy by black patients.

  12. Variations in body morphology explain sex differences in thermoeffector function during compensable heat stress.

    Science.gov (United States)

    Notley, Sean R; Park, Joonhee; Tagami, Kyoko; Ohnishi, Norikazu; Taylor, Nigel A S

    2017-05-01

    What is the central question of this study? Can sex-related differences in cutaneous vascular and sudomotor responses be explained primarily by variations in the ratio between body surface area and mass during compensable exercise that elicits equivalent heat-loss requirements and mean body temperature changes across participants? What is the main finding and its importance? Mass-specific surface area was a significant determinant of vasomotor and sudomotor responses in men and women, explaining 10-48% of the individual thermoeffector variance. Nonetheless, after accounting for changes in mean body temperature and morphological differences, sex explained only 5% of that inter-individual variability. It was concluded that sex differences in thermoeffector function are morphologically dependent, but not sex dependent. Sex is sometimes thought to be an independent modulator of cutaneous vasomotor and sudomotor function during heat exposure. Nevertheless, it was hypothesized that, when assessed during compensable exercise that evoked equal heat-loss requirements across participants, sex differences in those thermoeffectors would be explained by variations in the ratio between body surface area and mass (specific surface area). To evaluate that possibility, vasomotor and sudomotor functions were assessed in 60 individuals (36 men and 24 women) with widely varying (overlapping) specific surface areas (range, 232.3-292.7 and 241.2-303.1 cm 2  kg -1 , respectively). Subjects completed two trials in compensable conditions (28°C, 36% relative humidity) involving rest (20 min) and steady-state cycling (45 min) at fixed, area-specific metabolic heat-production rates (light, ∼135 W m -2 ; moderate, ∼200 W m -2 ). Equivalent heat-loss requirements and mean body temperature changes were evoked across participants. Forearm blood flow and vascular conductance were positively related to specific surface area during light work in men (r = 0.67 and r = 0

  13. Does individualism help explain differences in employers' stigmatizing attitudes toward disability across Chinese and American cities?

    Science.gov (United States)

    Rao, Deepa; Horton, Randall A; Tsang, Hector W H; Shi, Kan; Corrigan, Patrick W

    2010-11-01

    Stigmatizing attitudes toward people with disabilities can jeopardize such individuals' well-being and recovery through denial of employment and community isolation. By shaping social norms that define group membership, the construct of individualism may partially explain differences in stigmatizing attitudes across cultures. Further, widespread globalization has brought intensely individualistic social practices to certain segments of non-Western cultures. This paper examines whether the construct of individualism can help to explain cross-cultural differences in stigmatizing attitudes observed between American and Chinese employers. Employers (N = 879) from Beijing, Hong Kong, and Chicago provided information on their attitudes toward hiring people with disabilities, and path analyses were conducted to examine potential mediating relationships. Path analyses indicated that vertical individualism, along with perceived responsibility for acquiring a condition, partially mediated the relationship between culture and employers' negative attitudes about job candidates with disabilities. These results suggested that greater espousal of competitive and individualist values may drive stigmatizing attitudes across cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  14. No place like home? Explaining venue selection of regional offices in Brussels

    NARCIS (Netherlands)

    Beyers, J.; Donas, T. Fraussen B.

    2015-01-01

    While subnational authorities strongly mobilize in Brussels, they do not lobby all EU-level venues to the same extent. This article explains the varying intensity with which regional offices interact with various EU-level policy-making venues when seeking to influence EU policies. Theoretically, we

  15. Abilities and skills as factors explaining the differences in women entrepreneurship

    Directory of Open Access Journals (Sweden)

    Salvador Manzanera-Román

    2016-06-01

    Full Text Available This study takes part of the project Women and entrepreneurship from a competence perspective and aims to investigate the role of skills and abilities in explaining the women entrepreneurship. In this sense, it works on the idea that women entrepreneurs have specific competences, understood as the sum of skills and abilities, that characterize and determine the type of female entrepreneurship (typology, sector, size, innovation, creativity. Methodologically, it worked from a qualitative approach, supported by conducting semi-structured interviews of men and women from different socio-economic and business profiles. From an inductive and interpretive discursive analysis, it can be concluded that businessmen and businesswomen agree to grant several skills and abilities to women entrepreneurs, although there are significant differences between the perceptions of women and men, subsisting some gender stereotypes in defining the profile of women entrepreneurs.

  16. Cognitive abilities, monitoring, and control explain individual differences in heuristics and biases

    Directory of Open Access Journals (Sweden)

    Simon Anthony Jackson

    2016-10-01

    Full Text Available In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgements, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing that lower monitoring confidence and higher control thresholds promote error checking. Participants (N = 250 completed tasks assessing their fluid reasoning abilities, stable monitoring confidence levels, and the control threshold they impose on their decisions. They also completed seven typical heuristic and biases tasks such as the cognitive reflection test and resistance to framing. Using structural equation modelling, we found that individuals with higher reasoning abilities, lower monitoring confidence and higher control threshold performed significantly and, at times, substantially better on the heuristic and biases tasks. Individuals with higher control thresholds also showed lower preferences for risky alternatives in a gambling task. Furthermore, residual correlations among the heuristic and biases tasks were reduced to null, indicating that cognitive abilities, monitoring confidence and control thresholds accounted for their shared variance. Implications include the proposal that the capacity to detect errors does not differ between individuals. Rather, individuals might adopt varied strategies that promote error checking to different degrees, regardless of whether they have made a mistake or not. The results support growing evidence that decision making involves cognitive abilities that construct actions and monitoring and control processes that manage their initiation.

  17. Cognitive Abilities, Monitoring Confidence, and Control Thresholds Explain Individual Differences in Heuristics and Biases.

    Science.gov (United States)

    Jackson, Simon A; Kleitman, Sabina; Howie, Pauline; Stankov, Lazar

    2016-01-01

    In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence, and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgments, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing that lower monitoring confidence and higher control thresholds promote error checking. Participants ( N = 250) completed tasks assessing their fluid reasoning abilities, stable monitoring confidence levels, and the control threshold they impose on their decisions. They also completed seven typical heuristic and biases tasks such as the cognitive reflection test and Resistance to Framing. Using structural equation modeling, we found that individuals with higher reasoning abilities, lower monitoring confidence, and higher control threshold performed significantly and, at times, substantially better on the heuristic and biases tasks. Individuals with higher control thresholds also showed lower preferences for risky alternatives in a gambling task. Furthermore, residual correlations among the heuristic and biases tasks were reduced to null, indicating that cognitive abilities, monitoring confidence, and control thresholds accounted for their shared variance. Implications include the proposal that the capacity to detect errors does not differ between individuals. Rather, individuals might adopt varied strategies that promote error checking to different degrees, regardless of whether they have made a mistake or not. The results support growing evidence that decision-making involves cognitive abilities that construct actions and monitoring and control processes that manage their initiation.

  18. A model of how different biology experts explain molecular and cellular mechanisms.

    Science.gov (United States)

    Trujillo, Caleb M; Anderson, Trevor R; Pelaez, Nancy J

    2015-01-01

    Constructing explanations is an essential skill for all science learners. The goal of this project was to model the key components of expert explanation of molecular and cellular mechanisms. As such, we asked: What is an appropriate model of the components of explanation used by biology experts to explain molecular and cellular mechanisms? Do explanations made by experts from different biology subdisciplines at a university support the validity of this model? Guided by the modeling framework of R. S. Justi and J. K. Gilbert, the validity of an initial model was tested by asking seven biologists to explain a molecular mechanism of their choice. Data were collected from interviews, artifacts, and drawings, and then subjected to thematic analysis. We found that biologists explained the specific activities and organization of entities of the mechanism. In addition, they contextualized explanations according to their biological and social significance; integrated explanations with methods, instruments, and measurements; and used analogies and narrated stories. The derived methods, analogies, context, and how themes informed the development of our final MACH model of mechanistic explanations. Future research will test the potential of the MACH model as a guiding framework for instruction to enhance the quality of student explanations. © 2015 C. M. Trujillo et al. CBE—Life Sciences Education © 2015 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  19. Individual differences in positive and negative emotion regulation: Which strategies explain variability in loneliness?

    Science.gov (United States)

    Kearns, Sinead M; Creaven, Ann-Marie

    2017-02-01

    Loneliness is the distressing feeling accompanying the perception that one's social needs are not being met by one's social relationships. Conceptual models point to a role for cognitive factors in this experience. Because research on determinants of loneliness is sparse, this study investigates associations between individual differences in emotion regulation (ER) and loneliness. Participants (N = 116) completed measures of loneliness, and a vignette-based measure of adaptive and maladaptive ER in response to positive and negative scenarios. Regression analyses indicated that the regulation of positive and negative emotions explained comparable variance in loneliness, and associations were only partially reduced by the inclusion of social support. The specific strategies positive reappraisal, being present and negative mental time travel explained the most variance in loneliness. The findings are consistent with both the cognitive and the social needs models of loneliness and suggest that variability in ER strategies should be considered relevant to loneliness. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  20. Breast cancer survivors of different sexual orientations: which factors explain survivors' quality of life and adjustment?

    Science.gov (United States)

    Boehmer, U; Glickman, M; Winter, M; Clark, M A

    2013-06-01

    Little is known about differences by sexual orientation in explanatory factors of breast cancer survivors' quality of life, anxiety, and depression. Survivors were recruited from a cancer registry and additional survivors recruited through convenience methods. Data were collected via telephone survey from all 438 survivors, who were disease free and diagnosed with non-metastatic breast cancer an average of 5 years earlier. To explain quality of life, anxiety, and depression, we focused on sexual orientation as the primary independent factors, in addition, considering demographic, psychosocial, clinical, and functional factors as correlates. Sexual orientation had indirect associations with each of the outcomes, through disease-related and demographic factors as well as psychosocial and coping resources. The various explanatory models explain between 36% and 50% of the variance in outcomes and identified areas of strengths and vulnerabilities in sexual minority compared with heterosexual survivors. This study's findings of strengths among specific subgroups of sexual minority compared with heterosexual survivors require further explorations to identify the reasons for this finding. Most of the identified vulnerabilities among sexual minority compared with heterosexual survivors of breast cancer are amenable to change by interventions.

  1. Weight Loss After Bariatric Surgery: Do Clinical and Behavioral Factors Explain Racial Differences?

    Science.gov (United States)

    Wee, Christina C; Jones, Daniel B; Apovian, Caroline; Hess, Donald T; Chiodi, Sarah N; Bourland, Ashley C; Davis, Roger B; Schneider, Benjamin; Blackburn, George L; Marcantonio, Edward R; Hamel, Mary Beth

    2017-11-01

    Prior studies have suggested less weight loss among African American compared to Caucasian patients; however, few studies have been able to simultaneously account for baseline differences in other demographic, clinical, or behavioral factors. We interviewed patients at two weight loss surgery (WLS) centers and conducted chart reviews before and after WLS. We compared weight loss post-WLS by race/ethnicity and examined baseline demographic, clinical (BMI, comorbidities, quality of life), and behavioral (eating behavior, physical activity level, alcohol intake) factors that might explain observed racial differences in weight loss at 1 and 2 years after WLS. Of 537 participants who underwent either Roux-en-Y Gastric Bypass (54%) or gastric banding (46%), 85% completed 1-year follow-up and 73% completed 2-year follow-up. Patients lost a mean of 33.00% of initial weight at year 1 and 32.43% at year 2 after bypass and 16.07% and 17.56 % respectively after banding. After adjustment for other demographic characteristics and type of surgery, African Americans lost an absolute 5.93 ± 1.49% less weight than Caucasian patients after bypass (p loss among gastric bypass patients whereas having a diagnosis of anxiety disorder was associated with less weight loss among gastric banding patients. The association between race and weight loss did not substantially attenuate with additional adjustment for these clinical and behavioral factors, however. African American patients lost significantly less weight than Caucasian patients. Racial differences could not be explained by baseline demographic, clinical, or behavioral characteristics we examined.

  2. Explaining individual differences in alcohol intake in adults: evidence for genetic and cultural transmission?

    Science.gov (United States)

    van Beek, Jenny H D A; de Moor, Marleen H M; Geels, Lot M; Willemsen, Gonneke; Boomsma, Dorret I

    2014-03-01

    The current study aimed to describe what proportion of variation in adult alcohol intake is attributable to genetic differences among individuals and what proportion to differences in environmental experiences individuals have been exposed to. Effects of age, gender, spousal resemblance, and cultural transmission of alcohol intake from parents to offspring were taken into account. In a twin-family design, the effects of genetic and cultural transmission and shared and nonshared environment on alcohol intake were estimated with genetic structural equation models. Data originated from adult twins, their siblings, parents (n = 12,587), and spouses (n = 429) registered with the population-based Netherlands Twin Register (63.5% female; ages 18-97 years). Alcohol intake (grams per day) was higher among men than women and increased with age. Broad-sense heritability estimates were similar across sex and age (53%). Spousal resemblance was observed (r = .39) but did not significantly affect the heritability estimates. No effects of cultural transmission were detected. In total, 23% of the variation in alcohol intake was explained by additive genetic effects, 30% by dominant (nonadditive) gene action, and 47% by environmental effects that were not shared among family members. Individual differences in adult alcohol intake are explained by genetic and individual-specific environmental effects. The same genes are expressed in males and females and in younger and older participants. A substantial part of the heritability of alcohol intake is attributable to nonadditive gene action. Effects of cultural transmission that have been reported in adolescence are not present in adulthood.

  3. Different pathways explain alcohol related problems in female and male college students

    Science.gov (United States)

    Pedrelli, P.; Collado, A.; Shapero, B. G.; Brill, C.; MacPherson, L.

    2016-01-01

    Objectives Comprehensive models elucidating the intricate associations of depressive symptoms, coping motives, alcohol use, alcohol-related problems (ARP) and gender among young adults have been scarcely examined. This study investigated relationships among these variables and the effect of gender on these pathways. Methods College students (N = 163; 49.7% female) completed self-report measures on alcohol consumption, depressive symptoms, coping motives, and ARPs. Results Structural equation modeling showed that the association between depressive symptoms and ARPs was mediated by coping motives in both females and males. However, frequency of heavy alcohol use mediated the association between depressive symptoms and ARPs in females but not in males. Conclusions Different models explain the association between depressive symptoms and ARPs in male and female college students. Prevention programs aimed at reducing ARPs should focus on increasing alcohol screening among students with depressive symptoms, teaching coping skills, and emphasizing moderation in alcohol consumption. PMID:27219280

  4. A comparative perspective on intermarriage: explaining differences among national-origin groups in the United States.

    Science.gov (United States)

    Kalmijn, Matthijs; van Tubergen, Frank

    2010-05-01

    Little is known about the validity of group-level theories of ethnic intermarriage despite the fact that such theories are often invoked in explaining why certain ethnic groups are "closed," whereas others are relatively "open." We develop a comparative perspective by analyzing the marriage choices of 94 national-origin groups in the United States, using pooled data from the Current Population Surveys, 1994-2006, and multilevel models in which individual and contextual determinants of intermarriage are included simultaneously. Our analyses show large differences in endogamy across groups. After taking compositional effects into account, we find that both structural and cultural group-level factors have significant effects on endogamy. Cultural explanations (which focus on the role of norms and preferences) play a more important role than structural explanations (which focus on meeting and mating opportunities). Our results reinforce the common but untested interpretation of endogamy in terms of group boundaries.

  5. Different pathways explain alcohol-related problems in female and male college students.

    Science.gov (United States)

    Pedrelli, Paola; Collado, Anahi; Shapero, Benjamin G; Brill, Charlotte; MacPherson, Laura

    2016-10-01

    Comprehensive models elucidating the intricate associations of depressive symptoms, coping motives, alcohol use, alcohol-related problems (ARPs), and gender among young adults have been scarcely examined. This study investigated relationships among these variables and the effect of gender on these pathways. College students (N = 163; 49.7% female) completed self-report measures on alcohol consumption, depressive symptoms, coping motives, and ARPs. Structural equation modeling showed that the association between depressive symptoms and ARPs was mediated by coping motives in both females and males. However, frequency of heavy alcohol use mediated the association between depressive symptoms and ARPs in females but not in males. Different models explain the association between depressive symptoms and ARPs in male and female college students. Prevention programs aimed at reducing ARPs should focus on increasing alcohol screening among students with depressive symptoms, teaching coping skills, and emphasizing moderation in alcohol consumption.

  6. Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe?

    Directory of Open Access Journals (Sweden)

    Kelen Greta

    2008-06-01

    Full Text Available Abstract Background Antibiotics are widely-used medicines for which a more prudent use has been advocated to minimize development of resistance. There are considerable cross-national differences that can only partially be explained by epidemiological difference and variations in health care structure. The aim of this study was to explore whether cross-national differences in use of antibiotics (prescribed and non-prescribed are associated with differences between national cultures as described in Hofstede's model of cultural dimensions (Power Distance, Individualism, Masculinity, Uncertainty Avoidance and Long-Term Orientation. Methods Country-level data of prescribed antibiotic use and self-medication with antibiotics were correlated to country-specific scores of cultural dimensions obtained from Hofstede. Data on use of antibiotics were provided by three European studies, based on different methods and/or countries: Self-medication with Antibiotics and Resistance in Europe (SAR, based on a survey in 2003 on reported use of antibiotics in 19 countries, the European Surveillance on Antimicrobial Consumption, based on distribution and reimbursement of antibiotics in ambulatory care (1997–2002, and the 2002 interview-based Eurobarometer study, asking whether respondents had taken antibiotics in the previous 12 months. These studies provided data on antibiotics use for 27 European countries in total, for which scores of cultural dimensions were also available. The SAR-study differentiated between prescribed antibiotics and self-medication with antibiotics. Results Significant positive correlations were found for Power Distance Index with use of prescribed antibiotics in the three studies (rho between 0.59 and 0.62 and with self-medication (rho = 0.54 in the SAR study. Positive significant correlations were found for the Uncertainty Avoidance Index with the use of antibiotics as reported in two studies (rho between 0.57 and 0.59; for the SAR study

  7. Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe?

    Science.gov (United States)

    Deschepper, Reginald; Grigoryan, Larissa; Lundborg, Cecilia Stålsby; Hofstede, Geert; Cohen, Joachim; Kelen, Greta Van Der; Deliens, Luc; Haaijer-Ruskamp, Flora M

    2008-06-06

    Antibiotics are widely-used medicines for which a more prudent use has been advocated to minimize development of resistance. There are considerable cross-national differences that can only partially be explained by epidemiological difference and variations in health care structure. The aim of this study was to explore whether cross-national differences in use of antibiotics (prescribed and non-prescribed) are associated with differences between national cultures as described in Hofstede's model of cultural dimensions (Power Distance, Individualism, Masculinity, Uncertainty Avoidance and Long-Term Orientation). Country-level data of prescribed antibiotic use and self-medication with antibiotics were correlated to country-specific scores of cultural dimensions obtained from Hofstede. Data on use of antibiotics were provided by three European studies, based on different methods and/or countries: Self-medication with Antibiotics and Resistance in Europe (SAR), based on a survey in 2003 on reported use of antibiotics in 19 countries, the European Surveillance on Antimicrobial Consumption, based on distribution and reimbursement of antibiotics in ambulatory care (1997-2002), and the 2002 interview-based Eurobarometer study, asking whether respondents had taken antibiotics in the previous 12 months. These studies provided data on antibiotics use for 27 European countries in total, for which scores of cultural dimensions were also available. The SAR-study differentiated between prescribed antibiotics and self-medication with antibiotics. Significant positive correlations were found for Power Distance Index with use of prescribed antibiotics in the three studies (rho between 0.59 and 0.62) and with self-medication (rho = 0.54) in the SAR study. Positive significant correlations were found for the Uncertainty Avoidance Index with the use of antibiotics as reported in two studies (rho between 0.57 and 0.59; for the SAR study the correlations were insignificant). Masculinity

  8. Nonprofit Organizations in Danish Welfare Provision – Explaining Differences Across Welfare Areas

    DEFF Research Database (Denmark)

    Thøgersen, Malene

    This paper describes and analyzes the large variation in the proportion of non-profit providers across different welfare areas in Denmark with specific focus on two selected areas: Primary schools and care homes for elderly. With inspiration from niche theory, the aim is to get a deeper insight...... in the characteristics of the institutional framework in the two areas. The main argument of the paper is that non-profit welfare providers cannot be lumped together. It is necessary to take a closer look at both the differences and similarities across areas, but also across non-profit providers and their public...

  9. Defining race/ethnicity and explaining difference in research studies on lung function.

    Science.gov (United States)

    Braun, Lundy; Wolfgang, Melanie; Dickersin, Kay

    2013-06-01

    The 2005 guidelines of the American Thoracic Society/European Respiratory Society recommend the use of race- and/or ethnic-specific reference standards for spirometry. Yet definitions of the key variables of race and ethnicity vary worldwide. The purpose of this study was to determine whether researchers defined race and/or ethnicity in studies of lung function and how they explained any observed differences. Using the methodology of the systematic review, we searched PubMed in July 2008 and screened 10 471 titles and abstracts to identify potentially eligible articles that compared "white" to "other racial and ethnic groups". Of the 226 eligible articles published between 1922 and 2008, race and/or ethnicity was defined in 17.3%, with the proportion increasing to 70% in the 2000s for those using parallel controls. Most articles (83.6%) reported that "other racial and ethnic groups" have a lower lung capacity compared to "white"; 94% of articles failed to examine socioeconomic status. In the 189 studies that reported lower lung function in "other racial and ethnic groups", 21.8% and 29.4% of explanations cited inherent factors and anthropometric differences, respectively, whereas 23.1% of explanations cited environmental and social factors. Even though researchers sought to determine differences in lung function by race/ethnicity, they typically failed to define their terms and frequently assumed inherent (or genetic) differences.

  10. Brief report: Explaining differences in depressive symptoms between African American and European American adolescents.

    Science.gov (United States)

    Mrug, Sylvie; King, Vinetra; Windle, Michael

    2016-01-01

    African American adolescents report more depressive symptoms than their European American peers, but the reasons for these differences are poorly understood. This study examines whether risk factors in individual, family, school, and community domains explain these differences. African American and European American adolescents participating in the Birmingham Youth Violence Study (N = 594; mean age 13.2 years) reported on their depressive symptoms, pubertal development, aggressive and delinquent behavior, connectedness to school, witnessing violence, and poor parenting. Primary caregivers provided information on family income and their education level, marital status, and depression, and the adolescents' academic performance. African American adolescents reported more depressive symptoms than European American participants. Family socioeconomic factors reduced this difference by 29%; all risk factors reduced it by 88%. Adolescents' exposure to violence, antisocial behavior, and low school connectedness, as well as lower parental education and parenting quality, emerged as significant mediators of the group differences in depressive symptoms. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  11. Perception of racism explains the difference between Blacks' and Whites' level of healthcare trust.

    Science.gov (United States)

    Adegbembo, Albert O; Tomar, Scott L; Logan, Henrietta L

    2006-01-01

    To test the hypothesis that the level of healthcare trust does not differ between Blacks and Whites. Cross-sectional telephone-based survey. This study recruited low-income residents of Miami-Dade and Duval counties in Florida by using random-digit dialing (RDD). One thousand and five residents participated; however, analyses were limited to Black (n=550) or White (n=374) respondents. Trained interviewers used a structured questionnaire to obtain information about respondent demographics, trust in health care, perception of racism, and access to care. Black respondents included fewer males (P=.0146) and younger subjects (P racism than did Whites (Pracism into the model eliminated differences in trust between White and Black respondents. Overall, the model explaining healthcare trust accounted for 21.2% of the variance in trust; the model adjusted for respondents' county, demographics, access to care, and liking treatment during routine appointment. This study observed that perception of racism accounted for the residual differences in healthcare trust between Whites and Blacks; therefore, healthcare distrust may not be an attribute of Blacks. Respondents' experience with the healthcare system accounted for most of the difference in trust.

  12. Explaining socio-economic differences in intention to smoke among primary school children

    Science.gov (United States)

    2014-01-01

    Background Smoking prevalence is higher among low socio-economic status (LSES) groups, and this difference may originate from a higher intention to smoke in childhood. This study aims to identify factors that explain differences in intention to smoke between children living in high socio-economic status (HSES) and LSES neighbourhoods. Methods Cross-sectional data were derived from the baseline assessment of a smoking prevention intervention study. Dutch primary school children, aged 10 – 11 years (N = 2,612), completed a web-based questionnaire about their attitude, subjective norm, self-efficacy expectations, modelling and intention to smoke. Linear and logistic regression analyses were performed to assess potential individual cognitive (attitude, subjective norm and self-efficacy) and social environmental (modelling) mediators between SES and intention to smoke. Results Multiple mediation models indicated that modelling mediated the association between SES (B = -0.09 (p intention to smoke (B = 1.06 (p intention to smoke and the potential mediators indicating that there are no differences in mediating factors between boys and girls. Conclusions This study indicates that future smoking prevention studies may focus on the social environment to prevent smoking onset. However, replication of this study is warranted. Trial registration This study was approved by the Medical Ethics Committee of the Atrium-Orbis-Zuyd Hospital (NL32093.096.11 / MEC 11-T-25) and registered in the Dutch Trial Register (NTR3116). PMID:24555819

  13. Sparkling feather reflections of a bird-of-paradise explained by finite-difference time-domain modeling

    Science.gov (United States)

    Wilts, Bodo D.; Michielsen, Kristel; De Raedt, Hans; Stavenga, Doekele G.

    2014-01-01

    Birds-of-paradise are nature’s prime examples of the evolution of color by sexual selection. Their brilliant, structurally colored feathers play a principal role in mating displays. The structural coloration of both the occipital and breast feathers of the bird-of-paradise Lawes’ parotia is produced by melanin rodlets arranged in layers, together acting as interference reflectors. Light reflection by the silvery colored occipital feathers is unidirectional as in a classical multilayer, but the reflection by the richly colored breast feathers is three-directional and extraordinarily complex. Here we show that the reflection properties of both feather types can be quantitatively explained by finite-difference time-domain modeling using realistic feather anatomies and experimentally determined refractive index dispersion values of keratin and melanin. The results elucidate the interplay between avian coloration and vision and indicate tuning of the mating displays to the spectral properties of the avian visual system. PMID:24591592

  14. Sparkling feather reflections of a bird-of-paradise explained by finite-difference time-domain modeling.

    Science.gov (United States)

    Wilts, Bodo D; Michielsen, Kristel; De Raedt, Hans; Stavenga, Doekele G

    2014-03-25

    Birds-of-paradise are nature's prime examples of the evolution of color by sexual selection. Their brilliant, structurally colored feathers play a principal role in mating displays. The structural coloration of both the occipital and breast feathers of the bird-of-paradise Lawes' parotia is produced by melanin rodlets arranged in layers, together acting as interference reflectors. Light reflection by the silvery colored occipital feathers is unidirectional as in a classical multilayer, but the reflection by the richly colored breast feathers is three-directional and extraordinarily complex. Here we show that the reflection properties of both feather types can be quantitatively explained by finite-difference time-domain modeling using realistic feather anatomies and experimentally determined refractive index dispersion values of keratin and melanin. The results elucidate the interplay between avian coloration and vision and indicate tuning of the mating displays to the spectral properties of the avian visual system.

  15. Explaining interindividual differences in toddlers’ collaboration with unfamiliar peers: Individual, dyadic, and social factors

    Directory of Open Access Journals (Sweden)

    Nils eSchuhmacher

    2015-05-01

    Full Text Available During their third year of life, toddlers become increasingly skillful at coordinating their actions with peer partners and they form joint commitments in collaborative situations. However, little effort has been made to explain interindividual differences in collaboration among toddlers. Therefore, we examined the relative influence of distinct individual, dyadic, and social factors on toddlers’ collaborative activities (i.e., level of coordination and preference for joint activity in joint problem-solving situations with unfamiliar peer partners (n = 23 dyads aged M = 35.7 months. We analyzed the dyadic nonindependent data with mixed models. Results indicated that mothers’ expectations regarding their children’s social behaviors significantly predicted toddlers’ level of coordination. Furthermore, the models revealed that toddlers’ positive mutual experiences with the unfamiliar partner assessed during an initial free play period (Phase 1 and their level of coordination in an obligatory collaboration task (Phase 2 promoted toddlers’ preference for joint activity in a subsequent optional collaboration task (Phase 3. In contrast, children’s mastery motivation and shyness conflicted with their collaborative efforts. We discuss the role of parents’ socialization goals in toddlers’ development toward becoming active collaborators and discuss possible mechanisms underlying the differences in toddlers’ commitment to joint activities, namely social preferences and the trust in reliable cooperation partners.

  16. Residence times in shallow waters help explain regional differences in Wadden Sea eutrophication

    Science.gov (United States)

    Schwichtenberg, Fabian; Callies, Ulrich; van Beusekom, Justus E. E.

    2017-04-01

    Regional variations in eutrophication levels of tidal basins in the Wadden Sea can be caused by external factors, like organic matter import, and internal factors like the morphology and hydrodynamics of the receiving tidal basin. For instance, benthic nutrients from remineralized organic matter may be more concentrated in shallow basins or diluted in basins with high exchange rates. In addition, the location of a monitoring station may determine which basin-specific water masses are actually observed. In the present paper a hydrodynamic intertidal imprint (IMP) is estimated for ten stations in various tidal basins of the Wadden Sea. The fraction of time water masses spent in intertidal areas prior to observation is calculated by linking the Lagrangian transport module PELETS to already existing hourly reconstructions of currents between 1959 and 2003. Irrespective of water depth, additional calculations of mean residence times (MRT) in the Wadden Sea indicate whether, in the case of low IMP values, water masses originate from coastal areas or tidal channels. Results show distinct regional differences, with highest values in the eastern part of the Dutch sector of the southern Wadden Sea (IMP=77%, MRT=99%) and lowest values in the German/Danish sector of the northern Wadden Sea (IMP=1.1%, MRT=21%). The IMP correlates positively with observed nutrient levels (R2=0.83). Evidently, this residence time-based intertidal signal is pivotal in explaining regional variations in eutrophication levels revealed by long-term comparative data from different monitoring stations.

  17. Assessing labour strength in Serbia, Croatia and Slovenia: How to explain the differences?

    Directory of Open Access Journals (Sweden)

    Nikola Kosović

    2016-05-01

    Full Text Available This paper assesses the current strength of labour unions in Serbia, Croatia and Slovenia and elaborates on the main factors that have led to the current situation. The first part of the paper includes an in-depth literature review of the current state-of-the-art in assessing the labour strength across Europe, with special emphasis on post-communist countries. The second part of the paper provides the assessment of labour union strength in the surveyed countries. The authors argue that there are significant differences in the roles of labour movements. Serbia and Slovenia quite differ, with extremely weak and extremely strong labour movements, respectively, while Croatia is located in between. Kosović and Copîl also elaborate on the causes of such weaknesses. They identify four main factors: communist legacy, nationalistic elites, economic crisis and foreign influence, and the lack of trust among citizens, and conclude that it is impossible to explain such a complex issue as labour strength by observing any of these factors separately. However, taken together, they all provide a quality explanation of the current union strength in the observed countries.

  18. Cerebrovascular responses during rowing: Do circadian rhythms explain morning and afternoon performance differences?

    Science.gov (United States)

    Faull, O K; Cotter, J D; Lucas, S J E

    2015-08-01

    The purpose of this study was to characterize cerebrovascular responses to rowing exercise, investigating whether their diurnal variation might explain performance differences across a day. Twelve male rowers completed incremental rowing exercise and a 2000-m ergometer time trial at 07:00 h and 16:00 h, 1 week apart, while middle cerebral artery velocity (MCAv), cerebral (prefrontal), and muscular (vastus lateralis) tissue oxygenation and hemoglobin volume (via near-infrared spectroscopy), heart rate, and pressure of end-tidal CO2 (PET CO2) were recorded. MCAv was 20-25% above resting levels (68 ± 12 cm/s) during submaximal and maximal exercise intensities, despite PET CO2 being reduced during maximal efforts (down ∼ 0.5-0.8 kPa); thus revealing a different perfusion profile to the inverted-U observed in other exercise modes. The afternoon time trial was 3.4 s faster (95% confidence interval 0.9-5.8 s) and mean power output 3.2% higher (337 vs 347 W; P = 0.04), in conjunction with similar exercise-induced elevations in MCAv (P = 0.60) and reductions in cerebral oxygenation (TOI) (P = 0.12). At the muscle, afternoon trials involved similar oxygen extraction (HHb volume and TOI) albeit from a relatively lower total Hb volume (P rowing performance was better in the afternoon, but not in conjunction with differences in MCAv or exercise-induced differences in cerebral oxygenation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Selection and reduced population size cannot explain higher amounts of Neandertal ancestry in East Asian than in European human populations.

    Science.gov (United States)

    Kim, Bernard Y; Lohmueller, Kirk E

    2015-03-05

    It has been hypothesized that the greater proportion of Neandertal ancestry in East Asians than in Europeans is due to the fact that purifying selection is less effective at removing weakly deleterious Neandertal alleles from East Asian populations. Using simulations of a broad range of models of selection and demography, we have shown that this hypothesis cannot account for the higher proportion of Neandertal ancestry in East Asians than in Europeans. Instead, more complex demographic scenarios, most likely involving multiple pulses of Neandertal admixture, are required to explain the data. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  20. Strong Selective Sweeps on the X Chromosome in the Human-Chimpanzee Ancestor Explain Its Low Divergence.

    Directory of Open Access Journals (Sweden)

    Julien Y Dutheil

    2015-08-01

    Full Text Available The human and chimpanzee X chromosomes are less divergent than expected based on autosomal divergence. We study incomplete lineage sorting patterns between humans, chimpanzees and gorillas to show that this low divergence can be entirely explained by megabase-sized regions comprising one-third of the X chromosome, where polymorphism in the human-chimpanzee ancestral species was severely reduced. We show that background selection can explain at most 10% of this reduction of diversity in the ancestor. Instead, we show that several strong selective sweeps in the ancestral species can explain it. We also report evidence of population specific sweeps in extant humans that overlap the regions of low diversity in the ancestral species. These regions further correspond to chromosomal sections shown to be devoid of Neanderthal introgression into modern humans. This suggests that the same X-linked regions that undergo selective sweeps are among the first to form reproductive barriers between diverging species. We hypothesize that meiotic drive is the underlying mechanism causing these two observations.

  1. [The Swedish stroke register indicates differences in stroke care. Unconscious discrimination might explain some of the differences].

    Science.gov (United States)

    Eriksson, Marie; Glader, Eva-Lotta; Norrving, Bo; Asplund, Kjell

    2015-12-15

    In this article, results from a series of studies on the relationships between socioeconomic factors and stroke processes (stroke unit care, acute reperfusion treatment, secondary prevention with oral anticoagulants and statins) and outcomes (long-term survival, return to work and risk of suicide and suicide attempts) are summarized. The overall pattern is that acute and secondary prevention interventions and prognosis are better in patients with a high compared with a low level of education, better in people with high than low income, better in people who are cohabitant than single. As to country of birth, a more complex pattern has emerged. Unmeasured confounding may possibly explain part of the difference, but the socioeconomic gradients remain after adjustment for multiple potential confounders, leaving the possibility that there is an element of unconscious discrimination in stroke care.

  2. Near surface swimming of Salmonella Typhimurium explains target-site selection and cooperative invasion.

    Directory of Open Access Journals (Sweden)

    Benjamin Misselwitz

    Full Text Available Targeting of permissive entry sites is crucial for bacterial infection. The targeting mechanisms are incompletely understood. We have analyzed target-site selection by S. Typhimurium. This enteropathogenic bacterium employs adhesins (e.g. fim and the type III secretion system 1 (TTSS-1 for host cell binding, the triggering of ruffles and invasion. Typically, S. Typhimurium invasion is focused on a subset of cells and multiple bacteria invade via the same ruffle. It has remained unclear how this is achieved. We have studied target-site selection in tissue culture by time lapse microscopy, movement pattern analysis and modeling. Flagellar motility (but not chemotaxis was required for reaching the host cell surface in vitro. Subsequently, physical forces trapped the pathogen for ∼1.5-3 s in "near surface swimming". This increased the local pathogen density and facilitated "scanning" of the host surface topology. We observed transient TTSS-1 and fim-independent "stopping" and irreversible TTSS-1-mediated docking, in particular at sites of prominent topology, i.e. the base of rounded-up cells and membrane ruffles. Our data indicate that target site selection and the cooperative infection of membrane ruffles are attributable to near surface swimming. This mechanism might be of general importance for understanding infection by flagellated bacteria.

  3. Differing chemical compositions of three teas may explain their different effects on acute blood pressure in spontaneously hypertensive rats.

    Science.gov (United States)

    Li, Shan-Bing; Li, Yi-Fang; Mao, Zhong-Fu; Hu, Hui-Hua; Ouyang, Shu-Hua; Wu, Yan-Ping; Tsoi, Bun; Gong, Pin; Kurihara, Hiroshi; He, Rong-Rong

    2015-04-01

    Heavy tea consumption is suggested to be unsuitable for hypertensive people. However, the bioactive substances in different varieties of tea leaves are very different. This study compares the effects of three Chinese teas - C. sinensis, C. ptilophylla and C. assamica var. kucha - on blood pressure (BP) and heart rate in spontaneously hypertensive rats (SHRs). Intragastric administration of C. sinensis extract led to an acute increase in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate in SHRs. However, C. ptilophylla and C. assamica var. kucha exerted no obvious influences on SBP, DBP or heart rate. Similar to the extract of C. sinensis, intragastric administration of caffeine also led to an acute increase in BP and heart rate in SHRs. In contrast, theobromine and theacrine - purine alkaloids predominantly contained in C. ptilophylla and C. assamica var. kucha, respectively - had no pressor effects. The effect of caffeine on BP was related to the regulation of plasma epinephrine and norepinephrine levels in SHRs. The different effects of C. sinensis, C. ptilophylla and C. assamica var. kucha on BP might be explained, at least partially, by the differences in the varieties and contents of purine alkaloids. © 2014 Society of Chemical Industry.

  4. Explaining differences in perceived health-related quality of life: a study within the Spanish population.

    Science.gov (United States)

    Martín-Fernández, Jesús; Ariza-Cardiel, Gloria; Polentinos-Castro, Elena; Sanz-Cuesta, Teresa; Sarria-Santamera, Antonio; Del Cura-González, Isabel

    2017-09-25

    To assess the burden of several determinants on health-related quality of life (HRQOL) and to study its heterogeneity among the different Spanish regions. Cross-sectional study. Data were obtained from the Spanish National Health Survey (2012), and HRQOL was measured using the EQ-5D-5L questionnaire (utility and visual analogue scale -VAS- scores). Demographic variables, physical health condition, social variables, mental health status, and lifestyle were also analysed. Tobit regression models were employed to study the relationships between expressed HRQOL and personal characteristics. A total of 20,979 surveys were obtained. Of them, 62.4% expressed a utility score of 1, corresponding to perfect health (95%CI: 61.8%-63.2%), and 54.2% showed VAS scores ≥80 (95%CI: 53.5%-54.9%). HRQOL was mainly described as a function of age, chronic limitation in daily activities, and mental health status. Belonging to a higher-class strata and physical activity were related to better self-perceived HRQOL. Ageing worsened perceived HRQOL, but did not influence its determinants, and differences in HRQOL by regions were also not significant after model adjustment. HRQOL perception in the Spanish population varied slightly depending on the measure used (utilities index or VAS). Age, chronic limitations in daily life, and mental health status best explained the variability in perception, and no meaningful differences in HRQOL perception among regions were found after adjustment. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Gut check: reappraisal of disgust helps explain liberal-conservative differences on issues of purity.

    Science.gov (United States)

    Feinberg, Matthew; Antonenko, Olga; Willer, Robb; Horberg, E J; John, Oliver P

    2014-06-01

    Disgust plays an important role in conservatives' moral and political judgments, helping to explain why conservatives and liberals differ in their attitudes on issues related to purity. We examined the extent to which the emotion-regulation strategy reappraisal drives the disgust-conservatism relationship. We hypothesized that disgust has less influence on the political and moral judgments of liberals because they tend to regulate disgust reactions through emotional reappraisal more than conservatives. Study 1a found that a greater tendency to reappraise disgust was negatively associated with conservatism, independent of disgust sensitivity. Study 1b replicated this finding, demonstrating that the effect of reappraisal is unique to disgust. In Study 2, liberals condemned a disgusting act less than conservatives, and did so to the extent that they reappraised their initial disgust response. Study 3 manipulated participants' use of reappraisal when exposed to a video of men kissing. Conservatives instructed to reappraise their emotional reactions subsequently expressed more support for same-sex marriage than conservatives in the control condition, demonstrating attitudes statistically equivalent to liberal participants.

  6. The role of income differences in explaining social inequalities in self rated health in Sweden and Britain

    DEFF Research Database (Denmark)

    Yngwe, M A; Diderichsen, F; Whitehead, M

    2001-01-01

    STUDY OBJECTIVE: To analyse to what extent differences in income, using two distinct measures-as distribution across quintiles and poverty-explain social inequalities in self rated health, for men and women, in Sweden and Britain. DESIGN: Series of cross sectional surveys, the Swedish Survey....... In Britain the distribution across income quintiles explained 47% of the social inequalities in self rated health among women and 31% among men, while in Sweden it explained, for women 13% and for men 20%. Poverty explained 22% for British women and 8% for British men of the social inequalities in self rated...... health, while in Sweden poverty explained much less (men 2.5% and women 0%). CONCLUSIONS: The magnitude of social inequalities in self rated health was similar in Sweden and in Britain. However, the distribution of income across occupational social classes explains a larger part of these inequalities...

  7. Can Carbon Fluxes Explain Differences in Soil Organic Carbon Storage under Aspen and Conifer Forest Overstories?

    Directory of Open Access Journals (Sweden)

    Antra Boča

    2017-04-01

    Full Text Available Climate- and management-induced changes in tree species distributions are raising questions regarding tree species-specific effects on soil organic carbon (SOC storage and stability. Quaking aspen (Populus tremuloides Michx. is the most widespread tree species in North America, but fire exclusion often promotes the succession to conifer dominated forests. Aspen in the Western US have been found to store more SOC in the mineral soil than nearby conifers, but we do not yet fully understand the source of this differential SOC accumulation. We measured total SOC storage (0–50 cm, characterized stable and labile SOC pools, and quantified above- and belowground litter inputs and dissolved organic carbon (DOC fluxes during snowmelt in plots located in N and S Utah, to elucidate the role of foliage vs. root detritus in SOC storage and stabilization in both ecosystems. While leaf litterfall was twice as high under aspen as under conifers, input of litter-derived DOC with snowmelt water was consistently higher under conifers. Fine root (<2 mm biomass, estimated root detritus input, and root-derived DOC fluxes were also higher under conifers. A strong positive relationship between root and light fraction C content suggests that root detritus mostly fueled the labile fraction of SOC. Overall, neither differences in above- and belowground detritus C inputs nor in detritus-derived DOC fluxes could explain the higher and more stable SOC pools under aspen. We hypothesize that root–microbe–soil interactions in the rhizosphere are more likely to drive these SOC pool differences.

  8. Contribution of Frailty Markers in Explaining Differences Among Individuals in Five Samples of Older Persons

    NARCIS (Netherlands)

    Sourial, N.; Bergman, H.; Karunananthan, S.; Wolfson, C.; Guralnik, J.; Payette, H.; Gutierrez-Robledo, L.; Deeg, D.J.H.; Fletcher, J.D.; Puts, M.T.; Zhu, B.; Beland, F.

    2012-01-01

    Background: There has been little research on the relative importance of frailty markers. The objective was to investigate the association among seven frailty domains (nutrition, physical activity, mobility, strength, energy, cognition, and mood) and their relative contribution in explaining

  9. A COMPARATIVE PERSPECTIVE ON INTERMARRIAGE: EXPLAINING DIFFERENCES AMONG NATIONAL-ORIGIN GROUPS IN THE UNITED STATES

    National Research Council Canada - National Science Library

    MATTHIJS KALMIJN; FRANK VAN TUBERGEN

    2010-01-01

    Little is known about the validity of group-level theories of ethnic intermarriage despite the fact that such theories are often invoked in explaining why certain ethnic groups are "closed, "whereas...

  10. Differences in oral sexual behaviors by gender, age, and race explain observed differences in prevalence of oral human papillomavirus infection.

    Science.gov (United States)

    D'Souza, Gypsyamber; Cullen, Kevin; Bowie, Janice; Thorpe, Roland; Fakhry, Carole

    2014-01-01

    This study explores whether gender, age and race differences in oral sexual behavior account for the demographic distribution of oral human papillomavirus infection (HPV) and HPV-positive oropharyngeal cancer (HPV-OSCC). This analysis included 2,116 men and 2,140 women from NHANES (2009-10) who answered a behavioral questionnaire and provided an oral-rinse sample for HPV detection. Weighted prevalence estimates and prevalence ratios (PR) were calculated for sexual behaviors and oral HPV infection by gender, age-cohort (20-29, 30-44, 45-59, 60-69), and race, and contrasted with incidence rate ratios (IRR) of OSCC from SEER 2009. Multivariate logistic regression was used to evaluate predictors of oral sexual behavior and oral HPV16 infection. Differences in oral sexual behavior were observed by gender, age-cohort and race. Most men (85.4%) and women (83.2%) had ever performed oral sex, but men had more lifetime oral and vaginal sexual partners and higher oral HPV16 prevalence than women (each pHPV16 prevalence was similar. Prevalence ratios (PR) of ever oral sex in men vs. women (PR = 1.03), and 45-59 vs. 30-44 year-old men (PR = 0.96) were modest relative to ratios for oral HPV16 infection (PRs = 1.3-6.8) and OSCC (IRR = 4.7-8.1). In multivariate analysis, gender, age-cohort, and race were significant predictors of oral sexual behavior. Oral sexual behavior was the primary predictor of oral HPV16 infection; once this behavior was adjusted for, age-cohort and race were no longer associated with oral HPV16. There are differences in oral sexual behaviors when considering gender, age-cohort and race which explain observed epidemiologic differences in oral HPV16 infection across these groups.

  11. Differential androgen receptor signals in different cells explain why androgen-deprivation therapy of prostate cancer fails.

    Science.gov (United States)

    Niu, Y; Chang, T-M; Yeh, S; Ma, W-L; Wang, Y Z; Chang, C

    2010-06-24

    Prostate cancer is one of the major causes of cancer-related death in the western world. Androgen-deprivation therapy (ADT) for the suppression of androgens binding to the androgen receptor (AR) has been the norm of prostate cancer treatment. Despite early success to suppress prostate tumor growth, ADT eventually fails leading to recurrent tumor growth in a hormone-refractory manner, even though AR remains to function in hormone-refractory prostate cancer. Interestingly, some prostate cancer survivors who received androgen replacement therapy had improved quality of life without adverse effect on their cancer progression. These contrasting clinical data suggest that differential androgen/AR signals in individual cells of prostate tumors can exist in the same or different patients, and may be used to explain why ADT of prostate cancer fails. Such a hypothesis is supported by the results obtained from transgenic mice with selective knockout of AR in prostatic stromal vs epithelial cells and orthotopic transplants of various human prostate cancer cell lines with AR over-expression or knockout. These studies concluded that AR functions as a stimulator for prostate cancer proliferation and metastasis in stromal cells, as a survival factor of prostatic cancer epithelial luminal cells, and as a suppressor for prostate cancer basal intermediate cell growth and metastasis. These dual yet opposite functions of the stromal and epithelial AR may challenge the current ADT to battle prostate cancer and should be taken into consideration when developing new AR-targeting therapies in selective prostate cancer cells.

  12. Anatomic variation and orgasm: Could variations in anatomy explain differences in orgasmic success?

    Science.gov (United States)

    Emhardt, E; Siegel, J; Hoffman, L

    2016-07-01

    Though the public consciousness is typically focused on factors such as psychology, penis size, and the presence of the "G-spot," there are other anatomical and neuro-anatomic differences that could play an equal, or more important, role in the frequency and intensity of orgasms. Discovering these variations could direct further medical or procedural management to improve sexual satisfaction. The aim of this study is to review the available literature of anatomical sexual variation and to explain why this variation may predispose some patients toward a particular sexual experience. In this review, we explored the available literature on sexual anatomy and neuro-anatomy. We used PubMed and OVID Medline for search terms, including orgasm, penile size variation, clitoral variation, Grafenberg spot, and benefits of orgasm. First we review the basic anatomy and innervation of the reproductive organs. Then we describe several anatomical variations that likely play a superior role to popular known variation (penis size, presence of g-spot, etc). For males, the delicate play between the parasympathetic and sympathetic nervous systems is vital to achieve orgasm. For females, the autonomic component is more complex. The clitoris is the primary anatomical feature for female orgasm, including its migration toward the anterior vaginal wall. In conclusions, orgasms are complex phenomena involving psychological, physiological, and anatomic variation. While these variations predispose people to certain sexual function, future research should explore how to surgically or medically alter these. Clin. Anat. 29:665-672, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. Solvent selection for explaining the morphology of nitroguanidine crystal by molecular dynamics simulation

    Science.gov (United States)

    Song, Liang; Chen, Lizhen; Cao, Duanlin; Wang, Jianlong

    2018-02-01

    In this article, a method was performed to predict the morphology of needle-shaped crystals by analyzing the growth mechanisms for the various crystal faces. As an example, the crystal morphology of a nitroguanidine (NQ) was investigated via molecular dynamics simulations. The modified attachment energy (MEA) model was constructed by introducing surface chemistry terms and the relevant morphology of the habit crystal faces. The results indicate that the growth morphology of NQ in vacuum is dominated by {2 2 0}, {0 4 0}, {1 1 1}, {1 3 1} and {3 1 1} faces. The {2 2 0} and {0 4 0} faces are parallel to the elongation direction of the crystal, while the other faces are at the needle tips direction. The atoms or atomic groups exposed in crystal surface were used to analyze the relationship between structure and morphology. Compared to the surrounding faces, the needle tip faces have a large number of polar atoms or atomic groups. The needle tip faces have a high electronegativity on N, O atoms via molecular electrostatic potential (ESP) analysis. Furthermore, the protic solvent was used to reduce the attachment energy of the tip surfaces for achieving the purpose of inhibiting the growth of needle tips. Gamma-butyrolactone as the selected solvent inhibited effectively the growth of the needle tip faces. The predicted result is serviceable for the formation design.

  14. Proteomic and metabolic traits of grape exocarp to explain different anthocyanin concentrations of the cultivars

    Directory of Open Access Journals (Sweden)

    Alfredo Simone Negri

    2015-08-01

    Full Text Available The role of grape berry skin as a protective barrier against damage by physical injuries and pathogen attacks requires a metabolism able to sustain biosynthetic activities such as those relating to secondary compounds (i.e. flavonoids. In order to draw the attention on these biochemical processes, a proteomic and metabolomic comparative analysis was performed among Riesling Italico, Pinot Gris, Pinot Noir and Croatina cultivars, which are known to accumulate anthocyanins to a different extent. The application of multivariate statistics on the dataset pointed out that the cultivars were distinguishable from each other and the order in which they were grouped mainly reflected their relative anthocyanin contents. Sorting the spots according to their significance 100 proteins were characterized by LC-ESI-MS/MS. Through GC-MS, performed in Selected Ion Monitoring (SIM mode, 57 primary metabolites were analyzed and the differences in abundance of 16 of them resulted statically significant to ANOVA test. Considering the functional distribution, the identified proteins were involved in many physiological processes such as stress, defense, carbon metabolism, energy conversion and secondary metabolism. The trends of some metabolites were related to those of the protein data.Taken together, the results permitted to highlight the relationships between the secondary compound pathways and the main metabolism (e.g. glycolysis and TCA cycle. Moreover, the trend of accumulation of many proteins involved in stress responses, reinforced the idea that they could play a role in the cultivar specific developmental plan.

  15. Proteomic and metabolic traits of grape exocarp to explain different anthocyanin concentrations of the cultivars.

    Science.gov (United States)

    Negri, Alfredo S; Prinsi, Bhakti; Failla, Osvaldo; Scienza, Attilio; Espen, Luca

    2015-01-01

    The role of grape berry skin as a protective barrier against damage by physical injuries and pathogen attacks requires a metabolism able to sustain biosynthetic activities such as those relating to secondary compounds (i.e., flavonoids). In order to draw the attention on these biochemical processes, a proteomic and metabolomic comparative analysis was performed among Riesling Italico, Pinot Gris, Pinot Noir, and Croatina cultivars, which are known to accumulate anthocyanins to a different extent. The application of multivariate statistics on the dataset pointed out that the cultivars were distinguishable from each other and the order in which they were grouped mainly reflected their relative anthocyanin contents. Sorting the spots according to their significance 100 proteins were characterized by LC-ESI-MS/MS. Through GC-MS, performed in Selected Ion Monitoring (SIM) mode, 57 primary metabolites were analyzed and the differences in abundance of 16 of them resulted statistically significant to ANOVA test. Considering the functional distribution, the identified proteins were involved in many physiological processes such as stress, defense, carbon metabolism, energy conversion and secondary metabolism. The trends of some metabolites were related to those of the protein data. Taken together, the results permitted to highlight the relationships between the secondary compound pathways and the main metabolism (e.g., glycolysis and TCA cycle). Moreover, the trend of accumulation of many proteins involved in stress responses, reinforced the idea that they could play a role in the cultivar specific developmental plan.

  16. The variance of the locally measured Hubble parameter explained with different estimators

    DEFF Research Database (Denmark)

    Odderskov, Io Sandberg Hess; Hannestad, Steen; Brandbyge, Jacob

    2017-01-01

    to obtain a smaller variance than that found from studies based on the power spectrum. Although both approaches result in a variance too small to explain the discrepancy between the value of H0 from CMB measurements and the value measured in the local universe, these considerations are important in light...

  17. Snacking now or later? Individual differences in following intentions or habits explained by time perspective

    NARCIS (Netherlands)

    Onwezen, M.C.; Riet, J.P. van 't; Dagevos, H.; Sijtsema, S.J.; Snoek, H.M.

    2016-01-01

    Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why some

  18. Snacking now or later? Individual differences in following intentions or habits explained by time perspective

    NARCIS (Netherlands)

    Onwezen, M.C.; Riet, van 't J.; Dagevos, H.; Sijtsema, S.J.; Snoek, H.M.

    2016-01-01

    Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why

  19. A Model of How Different Biology Experts Explain Molecular and Cellular Mechanisms

    Science.gov (United States)

    Trujillo, Caleb M.; Anderson, Trevor R.; Pelaez, Nancy J.

    2015-01-01

    Constructing explanations is an essential skill for all science learners. The goal of this project was to model the key components of expert explanation of molecular and cellular mechanisms. As such, we asked: What is an appropriate model of the components of explanation used by biology experts to explain molecular and cellular mechanisms? Do…

  20. Differences in oral sexual behaviors by gender, age, and race explain observed differences in prevalence of oral human papillomavirus infection.

    Directory of Open Access Journals (Sweden)

    Gypsyamber D'Souza

    Full Text Available This study explores whether gender, age and race differences in oral sexual behavior account for the demographic distribution of oral human papillomavirus infection (HPV and HPV-positive oropharyngeal cancer (HPV-OSCC.This analysis included 2,116 men and 2,140 women from NHANES (2009-10 who answered a behavioral questionnaire and provided an oral-rinse sample for HPV detection. Weighted prevalence estimates and prevalence ratios (PR were calculated for sexual behaviors and oral HPV infection by gender, age-cohort (20-29, 30-44, 45-59, 60-69, and race, and contrasted with incidence rate ratios (IRR of OSCC from SEER 2009. Multivariate logistic regression was used to evaluate predictors of oral sexual behavior and oral HPV16 infection.Differences in oral sexual behavior were observed by gender, age-cohort and race. Most men (85.4% and women (83.2% had ever performed oral sex, but men had more lifetime oral and vaginal sexual partners and higher oral HPV16 prevalence than women (each p<0.001. 60-69 year olds (yo were less likely than 45-59 or 30-44 (yo to have performed oral sex (72.7%, 84.8%, and 90.3%, p<0.001, although oral HPV16 prevalence was similar. Prevalence ratios (PR of ever oral sex in men vs. women (PR = 1.03, and 45-59 vs. 30-44 year-old men (PR = 0.96 were modest relative to ratios for oral HPV16 infection (PRs = 1.3-6.8 and OSCC (IRR = 4.7-8.1. In multivariate analysis, gender, age-cohort, and race were significant predictors of oral sexual behavior. Oral sexual behavior was the primary predictor of oral HPV16 infection; once this behavior was adjusted for, age-cohort and race were no longer associated with oral HPV16.There are differences in oral sexual behaviors when considering gender, age-cohort and race which explain observed epidemiologic differences in oral HPV16 infection across these groups.

  1. Explaining geographic gradients in winter selection of landscapes by boreal caribou with implications under global changes in Eastern Canada.

    Directory of Open Access Journals (Sweden)

    Julien Beguin

    Full Text Available Many animal species exhibit broad-scale latitudinal or longitudinal gradients in their response to biotic and abiotic components of their habitat. Although knowing the underlying mechanism of these patterns can be critical to the development of sound measures for the preservation or recovery of endangered species, few studies have yet identified which processes drive the existence of geographical gradients in habitat selection. Using extensive spatial data of broad latitudinal and longitudinal extent, we tested three hypotheses that could explain the presence of geographical gradients in landscape selection of the endangered boreal woodland caribou (Rangifer tarandus caribou during winter in Eastern Canadian boreal forests: 1 climate-driven selection, which postulates that geographic gradients are surrogates for climatic gradients; 2 road-driven selection, which proposes that boreal caribou adjust their selection for certain habitat classes as a function of proximity to roads; and 3 an additive effect of both roads and climate. Our data strongly supported road-driven selection over climate influences. Thus, direct human alteration of landscapes drives boreal caribou distribution and should likely remain so until the climate changes sufficiently from present conditions. Boreal caribou avoided logged areas two-fold more strongly than burnt areas. Limiting the spread of road networks and accounting for the uneven impact of logging compared to wildfire should therefore be integral parts of any habitat management plan and conservation measures within the range of the endangered boreal caribou. The use of hierarchical spatial models allowed us to explore the distribution of spatially-structured errors in our models, which in turn provided valuable insights for generating alternative hypotheses about processes responsible for boreal caribou distribution.

  2. Health behaviours explain part of the differences in self reported health associated with partner/marital status in The Netherlands

    NARCIS (Netherlands)

    Joung, I. M.; Stronks, K.; van de Mheen, H.; Mackenbach, J. P.

    1995-01-01

    To describe the differences in health behaviours in disparate marital status groups and to estimate the extent to which these can explain differences in health associated with marital status. Baseline data of a prospective cohort study were used. Directly age standardised percentages of each marital

  3. Supplier selection using different metric functions

    Directory of Open Access Journals (Sweden)

    Omosigho S.E.

    2015-01-01

    Full Text Available Supplier selection is an important component of supply chain management in today’s global competitive environment. Hence, the evaluation and selection of suppliers have received considerable attention in the literature. Many attributes of suppliers, other than cost, are considered in the evaluation and selection process. Therefore, the process of evaluation and selection of suppliers is a multi-criteria decision making process. The methodology adopted to solve the supplier selection problem is intuitionistic fuzzy TOPSIS (Technique for Order Preference by Similarity to the Ideal Solution. Generally, TOPSIS is based on the concept of minimum distance from the positive ideal solution and maximum distance from the negative ideal solution. We examine the deficiencies of using only one metric function in TOPSIS and propose the use of spherical metric function in addition to the commonly used metric functions. For empirical supplier selection problems, more than one metric function should be used.

  4. Using Roald Dahl's "Charlie and the Chocolate Factory" to Teach Different Recruitment and Selection Paradigms

    Science.gov (United States)

    Billsberry, Jon; Gilbert, Louise H.

    2008-01-01

    This article makes a case for using Roald Dahl's children's fantasy and morality tale "Charlie and the Chocolate Factory" to teach recruitment and selection. It draws attention to its relevance in illustrating and explaining three different recruitment and selection paradigms: psychometric, social process, and fit. It argues that the use of this…

  5. Differences in xylem and leaf hydraulic traits explain differences in drought tolerance among mature Amazon rainforest trees.

    Science.gov (United States)

    Powell, Thomas L; Wheeler, James K; de Oliveira, Alex A R; da Costa, Antonio Carlos Lola; Saleska, Scott R; Meir, Patrick; Moorcroft, Paul R

    2017-10-01

    Considerable uncertainty surrounds the impacts of anthropogenic climate change on the composition and structure of Amazon forests. Building upon results from two large-scale ecosystem drought experiments in the eastern Brazilian Amazon that observed increases in mortality rates among some tree species but not others, in this study we investigate the physiological traits underpinning these differential demographic responses. Xylem pressure at 50% conductivity (xylem-P 50 ), leaf turgor loss point (TLP), cellular osmotic potential (π o ), and cellular bulk modulus of elasticity (ε), all traits mechanistically linked to drought tolerance, were measured on upper canopy branches and leaves of mature trees from selected species growing at the two drought experiment sites. Each species was placed a priori into one of four plant functional type (PFT) categories: drought-tolerant versus drought-intolerant based on observed mortality rates, and subdivided into early- versus late-successional based on wood density. We tested the hypotheses that the measured traits would be significantly different between the four PFTs and that they would be spatially conserved across the two experimental sites. Xylem-P 50 , TLP, and π o , but not ε, occurred at significantly higher water potentials for the drought-intolerant PFT compared to the drought-tolerant PFT; however, there were no significant differences between the early- and late-successional PFTs. These results suggest that these three traits are important for determining drought tolerance, and are largely independent of wood density-a trait commonly associated with successional status. Differences in these physiological traits that occurred between the drought-tolerant and drought-intolerant PFTs were conserved between the two research sites, even though they had different soil types and dry-season lengths. This more detailed understanding of how xylem and leaf hydraulic traits vary between co-occuring drought-tolerant and

  6. Explaining age differences in women's emotional well-being: The role of subjective experiences of aging.

    Science.gov (United States)

    Barrett, Anne E; Toothman, Erica L

    2016-01-01

    Our study examines explanations for the "paradox" of older women's better emotional well-being compared with younger women. We consider the role of subjective experiences of aging in a society that devalues older women. Using a sample of women (n = 872) from the National Survey of Midlife Development in the United States (1995-1996 and 2004-2006), we examine the role of five components of the subjective experience of aging in explaining older women's better emotional well-being compared with younger women: age identity, conceptions of the timing of middle age, aging attitudes, aging anxieties, and self-assessed physiological changes. We find that, compared with women 50-54 years old, those 35-39 years old report lower positive affect, and those 25-49 report higher negative affect. These patterns are partially explained by younger women's greater anxiety about declines in health and attractiveness and older women's more youthful identities. Our study underscores the value of considering the implications of our ageist and sexist society for women's emotional well-being across adulthood.

  7. Determining The Personality Of Selected Brands Through The Archetypes And Explaining The Way Of Perception Of Their Consumers

    OpenAIRE

    Naghmeh Sheibani Moghadam; Mojtaba Amiri; Tahmoures Hassan Gholipour

    2013-01-01

    Abstract The essential nature of brand is making differences. These days, emotional and symbolic features are so effective for making differences. One of the powerful and useful methods for making difference through these features is “Brand Personality” that means “the set of human characteristics associated with brand”. Here we use “Archetypes” for determining the brand personality. In this survey we determined: 1- The personality of selected brands through the archetypes, 2- The factors ...

  8. Herbivore trampling as an alternative pathway for explaining differences in nitrogen mineralization in moist grasslands

    NARCIS (Netherlands)

    Schrama, Maarten; Heijning, Pieter; Bakker, Jan P.; van Wijnen, Harm J.; Berg, Matty; Olff, Han; Niklaus, Pascal

    Studies addressing the role of large herbivores on nitrogen cycling in grasslands have suggested that the direction of effects depends on soil fertility. Via selection for high quality plant species and input of dung and urine, large herbivores have been shown to speed up nitrogen cycling in fertile

  9. Natural selection in a population of Drosophila melanogaster explained by changes in gene expression caused by sequence variation in core promoter regions.

    Science.gov (United States)

    Sato, Mitsuhiko P; Makino, Takashi; Kawata, Masakado

    2016-02-09

    Understanding the evolutionary forces that influence variation in gene regulatory regions in natural populations is an important challenge for evolutionary biology because natural selection for such variations could promote adaptive phenotypic evolution. Recently, whole-genome sequence analyses have identified regulatory regions subject to natural selection. However, these studies could not identify the relationship between sequence variation in the detected regions and change in gene expression levels. We analyzed sequence variations in core promoter regions, which are critical regions for gene regulation in higher eukaryotes, in a natural population of Drosophila melanogaster, and identified core promoter sequence variations associated with differences in gene expression levels subjected to natural selection. Among the core promoter regions whose sequence variation could change transcription factor binding sites and explain differences in expression levels, three core promoter regions were detected as candidates associated with purifying selection or selective sweep and seven as candidates associated with balancing selection, excluding the possibility of linkage between these regions and core promoter regions. CHKov1, which confers resistance to the sigma virus and related insecticides, was identified as core promoter regions that has been subject to selective sweep, although it could not be denied that selection for variation in core promoter regions was due to linked single nucleotide polymorphisms in the regulatory region outside core promoter regions. Nucleotide changes in core promoter regions of CHKov1 caused the loss of two basal transcription factor binding sites and acquisition of one transcription factor binding site, resulting in decreased gene expression levels. Of nine core promoter regions regions associated with balancing selection, brat, and CG9044 are associated with neuromuscular junction development, and Nmda1 are associated with learning

  10. Factors That May Explain Differences between Home and Clinic Meal Preparation Task Assessments in Frail Older Adults

    Science.gov (United States)

    Provencher, Veronique; Demers, Louise; Gelinas, Isabelle

    2012-01-01

    Meal preparation assessments conducted in clinical environments (such as rehabilitation settings) might not reflect frail patients' performance at home. In addition, factors that may explain differences in performance between settings remain unknown. The aim of this study was to compare home and clinic performance on meal preparation tasks in…

  11. The Role of Harsh Discipline in Explaining Sex Differences in Conduct Disorder: A Study of Opposite-Sex Twin Pairs

    Science.gov (United States)

    Meier, Madeline H.; Slutske, Wendy S.; Heath, Andrew C.; Martin, Nicholas G.

    2009-01-01

    In the current study, two hypotheses about the role of harsh discipline (HD) in explaining the sex difference in the prevalence of conduct disorder (CD) were evaluated: that boys exhibit more CD than girls because (1) they are exposed to more HD and/or (2) there is a greater association between HD and CD in boys. These hypotheses were evaluated in…

  12. Exposure to Pre- and Perinatal Risk Factors Partially Explains Mean Differences in Self-Regulation between Races.

    Directory of Open Access Journals (Sweden)

    J C Barnes

    Full Text Available To examine whether differential exposure to pre- and perinatal risk factors explained differences in levels of self-regulation between children of different races (White, Black, Hispanic, Asian, and Other.Multiple regression models based on data from the Early Childhood Longitudinal Study, Birth Cohort (n ≈ 9,850 were used to analyze the impact of pre- and perinatal risk factors on the development of self-regulation at age 2 years.Racial differences in levels of self-regulation were observed. Racial differences were also observed for 9 of the 12 pre-/perinatal risk factors. Multiple regression analyses revealed that a portion of the racial differences in self-regulation was explained by differential exposure to several of the pre-/perinatal risk factors. Specifically, maternal age at childbirth, gestational timing, and the family's socioeconomic status were significantly related to the child's level of self-regulation. These factors accounted for a statistically significant portion of the racial differences observed in self-regulation.The findings indicate racial differences in self-regulation may be, at least partially, explained by racial differences in exposure to pre- and perinatal risk factors.

  13. Explaining the Wealth Holdings of Different Cohorts: Productivity Growth and Social Security

    NARCIS (Netherlands)

    Kapteijn, A.; Alessie, R.; Lusardi, A.

    It is well-known that individuals born in different periods of time (cohorts or generations) exhibit different wealth accumulation paths. While previous studies have used cohort dummies to proxy for this fact, research in this area suffers from a serious identification problem, i.e., how to

  14. Explaining the wealth holdings of different cohorts: productivity growth and social security

    NARCIS (Netherlands)

    Kapteyn, Arie; Alessie, R.; Lusardi, Annamaria

    2003-01-01

    It is well-known that individuals born in different periods of time (cohorts or generations) exhibit different wealth accumulation paths. While previous studies have used cohort dummies to proxy for this fact, research in this area suffers from a serious identification problem, i.e., how to

  15. Explaining interspecific differences in sapling growth and shade tolerance in temperate forests

    NARCIS (Netherlands)

    Janse-ten Klooster, S.H.; Thomas, E.J.P.; Sterck, F.J.

    2007-01-01

    1. Species differences in growth and shade tolerance might contribute to coexistence of tree species. To explore how such differences depend on underlying plant traits, 14 tree species were investigated in temperate forests on sand and loess soils in the Netherlands. Plant traits were measured for

  16. Explaining Academic Success in Engineering Degree Programs : Do Female and Male Students Differ?

    NARCIS (Netherlands)

    Kamphorst, Jan C.; Hofman, W.H. Adriaan; Jansen, Ellen P.W.A.; Terlouw, Cees

    2015-01-01

    Background In Dutch engineering education, female students outperform male students. Using an interactionalist framework, this study explores factors that contribute to this gender-based difference. Purpose This study aims to answer two questions: Do female and male students differ in background

  17. A COMPARATIVE PERSPECTIVE ON INTERMARRIAGE: EXPLAINING DIFFERENCES AMONG NATIONAL-ORIGIN GROUPS IN THE UNITED STATES

    National Research Council Canada - National Science Library

    MATTHIJS KALMIJN; FRANK VAN TUBERGEN

    2010-01-01

    .... Our analyses show large differences in endogamy across groups. After taking compositional effects into account, we find that both structural and cultural group-level factors have significant effects on endogamy...

  18. Explaining differences between Bioaccumulation Measurements in laboratory and field data through use of probabilistic modeling approach

    NARCIS (Netherlands)

    Selck, H.; Drouillard, K.; Eisenreich, K.; Koelmans, A.A.; Palmqvist, A.; Ruus, A.; Salvito, D.; Schultz, I.; Stewart, R.; Weisbrod, A.; Brink, van den N.W.; Heuvel-Greve, van den M.J.

    2012-01-01

    In the regulatory context, bioaccumulation assessment is often hampered by substantial data uncertainty as well as by the poorly understood differences often observed between results from laboratory and field bioaccumulation studies. Bioaccumulation is a complex, multifaceted process, which calls

  19. How can individual differences in autobiographical memory distributions of older adults be explained?

    Science.gov (United States)

    Wolf, Tabea; Zimprich, Daniel

    2016-10-01

    The reminiscence bump phenomenon has frequently been reported for the recall of autobiographical memories. The present study complements previous research by examining individual differences in the distribution of word-cued autobiographical memories. More importantly, we introduce predictor variables that might account for individual differences in the mean (location) and the standard deviation (scale) of individual memory distributions. All variables were derived from different theoretical accounts for the reminiscence bump phenomenon. We used a mixed location-scale logitnormal model, to analyse the 4602 autobiographical memories reported by 118 older participants. Results show reliable individual differences in the location and the scale. After controlling for age and gender, individual proportions of first-time experiences and individual proportions of positive memories, as well as the ratings on Openness to new Experiences and Self-Concept Clarity accounted for 29% of individual differences in location and 42% of individual differences in scale of autobiographical memory distributions. Results dovetail with a life-story account for the reminiscence bump which integrates central components of previous accounts.

  20. Individual differences in temporal selective attention

    NARCIS (Netherlands)

    Willems, Charlotte

    2016-01-01

    Every waking moment we are bombarded with large amounts of information. Given the limited ability to process this information at a conscious level, some sort of selection for further processing is required to identify the most relevant information (e.g., other road users) while ignoring irrelevant

  1. Strong but diverging clonality - climate relationships of different plant clades explain weak overall pattern across China

    Science.gov (United States)

    Ye, Duo; Liu, Guofang; Song, Yao-Bin; Cornwell, William K.; Dong, Ming; Cornelissen, Johannes H. C.

    2016-06-01

    The clonal strategy should be relatively important in stressful environments (i.e. of low resource availability or harsh climate), e.g. in cold habitats. However, our understanding of the distribution pattern of clonality along environmental gradients is still far from universal. The weakness and inconsistency of overall clonality-climate relationships across taxa, as reported in previous studies, may be due to different phylogenetic lineages having fundamental differences in functional traits other than clonality determining their climate response. Thus, in this study we compared the clonality-climate relationships along a latitudinal gradient within and between different lineages at several taxonomic levels, including four major angiosperm lineages (Magnoliidae, Monocotyledoneae, Superrosidae and Superasteridae), orders and families. To this aim we used a species clonality dataset for 4015 vascular plant species in 545 terrestrial communities across China. Our results revealed clear predictive patterns of clonality proportion in relation to environmental gradients for the predominant representatives of each of the taxonomic levels above, but the relationships differed in shape and strength between the 4 major angiosperm lineages, between the 12 orders and between the 12 families. These different relationships canceled out one another when all lineages at a certain taxonomic level were pooled. Our findings highlight the importance of explicitly accounting for the functional or taxonomic scale for studying variation in plant ecological strategy across environmental gradients.

  2. Could the peer group explain school differences in pupil smoking rates? An exploratory study.

    Science.gov (United States)

    Turner, Katrina; West, Patrick; Gordon, Jacki; Young, Robert; Sweeting, Helen

    2006-05-01

    Schools differ in the proportion of their pupils who smoke. Such differences transcend pupil intake characteristics and relate to the internal life of the school. Although adolescents' smoking behaviour has been associated with that of their peers, little consideration has been given to whether peer structures and processes contribute to school differences in pupil smoking rates. In two relatively deprived Scottish schools, one with a higher and one with a lower rate of pupil smoking, 13 and 15 year-olds were surveyed. Sociometric data and information on pupils' smoking behaviour and views were gathered. Twenty-five single-sex discussion groups were then held with a sub-sample of the 13 year-olds in order to explore in detail their views on smoking, smokers and fellow pupils. Findings showed that in the higher smoking school, pupils were more often in groups, smokers were identified as popular, and attitudes (especially among non-smoking females) were more pro-smoking. In the lower smoking school, by contrast, there were more isolates and dyads, there were no popular smokers and attitudes (especially among non-smoking females) were much less pro-smoking. Thus, evidence suggests peer group structures and related influences could be one explanation for school differences in smoking, and that the popularity of smokers together with the views of non-smoking females may be particularly important in creating such differences.

  3. Explaining sex differences in lifespan in terms of optimal energy allocation in the baboon.

    Science.gov (United States)

    King, Annette M; Kirkwood, Thomas B L; Shanley, Daryl P

    2017-10-01

    We provide a quantitative test of the hypothesis that sex role specialization may account for sex differences in lifespan in baboons if such specialization causes the dependency of fitness upon longevity, and consequently the optimal resolution to an energetic trade-off between somatic maintenance and other physiological functions, to differ between males and females. We present a model in which females provide all offspring care and males compete for access to reproductive females and in which the partitioning of available energy between the competing fitness-enhancing functions of growth, maintenance, and reproduction is modeled as a dynamic behavioral game, with the optimal decision for each individual depending upon his/her state and the behavior of other members of the population. Our model replicates the sexual dimorphism in body size and sex differences in longevity and reproductive scheduling seen in natural populations of baboons. We show that this outcome is generally robust to perturbations in model parameters, an important finding given that the same behavior is seen across multiple populations and species in the wild. This supports the idea that sex differences in longevity result from differences in the value of somatic maintenance relative to other fitness-enhancing functions in keeping with the disposable soma theory. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  4. Explaining sex differences in lifespan in terms of optimal energy allocation in the baboon

    DEFF Research Database (Denmark)

    King, Annette M.; Kirkwood, Thomas B.L.; Shanley, Daryl P.

    2017-01-01

    We provide a quantitative test of the hypothesis that sex role specialization may account for sex differences in lifespan in baboons if such specialization causes the dependency of fitness upon longevity, and consequently the optimal resolution to an energetic trade-off between somatic maintenance...... scheduling seen in natural populations of baboons. We show that this outcome is generally robust to perturbations in model parameters, an important finding given that the same behavior is seen across multiple populations and species in the wild. This supports the idea that sex differences in longevity result...

  5. Can appearance conversations explain differences between gay and heterosexual men's body dissatisfaction?

    OpenAIRE

    Jankowski, GS; Diedrichs, PC; Halliwell, E

    2014-01-01

    Men's body dissatisfaction is prevalent and a serious health concern as it is associated with negative outcomes including depression, disordered eating, and anabolic steroid abuse. Gay men are particularly vulnerable to body dissatisfaction, perhaps due to heightened sociocultural appearance pressures experienced in gay subculture. Appearance conversations represent an underresearched, but potentially potent, mechanism of appearance pressures. The current study explored whether differences in...

  6. Do differences in inducible resistance explain the population dynamics of birch and pine defoliators?

    Science.gov (United States)

    Seppo Neuvonen; Pekka Niemela

    1991-01-01

    Damage inflicted by insects may trigger responses in their host plants resulting either in immediate effects on herbivores either rapidly or in effects upon subsequent herbivore generations. Differentiation between rapid and delayed inducible resistance is essential since the two responses affect the population dynamics of herbivores in fundamentally different ways (...

  7. Gun Cultures or Honor Cultures? Explaining Regional and Race Differences in Weapon Carrying

    Science.gov (United States)

    Felson, Richard B.; Pare, Paul-Philippe

    2010-01-01

    We use the National Violence against Women (and Men) Survey to examine the effects of region and race on the tendency to carry weapons for protection. We find that Southern and Western whites are much more likely than Northern whites to carry guns for self-protection, controlling for their risk of victimization. The difference between Southern and…

  8. Spatial variation in tuber depletion by swans explained by differences in net intake rates

    NARCIS (Netherlands)

    Nolet, BA; Langevoord, O; Bevan, RM; Engelaar, KR; Klaassen, M; Mulder, RJW

    We tested whether the spatial variation in resource depletion by Tundra Swans (Cygnus columbianus) foraging on belowground tubers of sage pondweed (Potnmogeton pectinatus) was caused by differences in net energy intake rates. The variation in giving up densities within the confines of one lake was

  9. Spatial variation in tuber depletion by swans explained by differences in net intake rates

    NARCIS (Netherlands)

    Nolet, B.A.; Langevoord, O.; Bevan, R.M.; Engelaar, K.R.; Klaassen, M.R.J.; Mulder, R.J.W.; Van Dijk, S.

    2001-01-01

    We tested whether the spatial variation in resource depletion by Tundra Swans (Cygnus columbianus) foraging on belowground tubers of sage pondweed (Potnmogeton pectinatus) was caused by differences in net energy intake rates. The variation in giving up densities within the confines of one lake was

  10. Individual Differences in Toddlers' Prosociality: Experiences in Early Relationships Explain Variability in Prosocial Behavior

    Science.gov (United States)

    Newton, Emily K.; Thompson, Ross A.; Goodman, Miranda

    2016-01-01

    Latent class logistic regression analysis was used to investigate sources of individual differences in profiles of prosocial behavior. Eighty-seven 18-month-olds were observed in tasks assessing sharing with a neutral adult, instrumentally helping a neutral adult, and instrumentally helping a sad adult. Maternal mental state language (MSL) and…

  11. 19 CFR 122.162 - Failure to notify and explain differences in air cargo manifest.

    Science.gov (United States)

    2010-04-01

    ... clerical error or other mistake; (3) There has been a loss of revenue to the U.S.; or (4) The port director.... Under this section, “clerical error or other mistake” means a non-negligent, inadvertant, or... may be determined that the differences were a result of negligence and not clerical error or other...

  12. An active lifestyle explains sex differences in physical performance in children before puberty.

    Science.gov (United States)

    De la Cruz-Sánchez, Ernesto; Pino-Ortega, José

    2010-06-01

    The aim of this study is to analyze differences according to sex in physical performance in children before puberty, as well as other health-related variables. Study population was 137 boys and 156 girls (9.99 +/- 0.79 years). We measured weight and height, physical performance using five field tests previously validated in children, habitual physical activity and diet quality. A multinomial logistic regression coefficient was established to calculate odd ratios (OR's) and 95% confidence intervals (CI's), to determine sex differences in performance, weight status, habitual physical activity and diet quality, and a t-test was calculated between active boys and active girls in order to establish differences in performance fitness test taking account habitual physical activity. Boys were more actives (OR 1.90, CI 1.03-3.49) and had better weight status than girls, while there was no difference in diet quality between sexes (OR 1.13, CI 0.67-1.89). In total sample, it was more probable to find greater physical fitness values in boys in all test performed. However, when both groups had a similar physical activity pattern, assessed physical fitness variables reached similar values and girls had better results only in flexibility. Sedentary patterns were more frequent in girls although there were no differences in diet quality between sexes. Girls tended to overweight more than boys did. Both sexes had a similar fitness performance before puberty for the same reported physical activity, except for flexibility, inferior in male subjects independently of their physical activity pattern.

  13. Psychological sex differences. Origins through sexual selection.

    Science.gov (United States)

    Buss, D M

    1995-03-01

    Men and women clearly differ in some psychological domains. A. H. Eagly (1995) shows that these differences are not artifactual or unstable. Ideally, the next scientific step is to develop a cogent explanatory framework for understanding why the sexes differ in some psychological domains and not in others and for generating accurate predictions about sex differences as yet undiscovered. This article offers a brief outline of an explanatory framework for psychological sex differences--one that is anchored in the new theoretical paradigm of evolutionary psychology. Men and women differ, in this view, in domains in which they have faced different adaptive problems over human evolutionary history. In all other domains, the sexes are predicted to be psychologically similar. Evolutionary psychology jettisons the false dichotomy between biology and environment and provides a powerful metatheory of why sex differences exist, where they exist, and in what contexts they are expressed (D. M. Buss, 1995).

  14. Does stage of cancer, comorbidity or lifestyle factors explain educational differences in survival after endometrial cancer?

    DEFF Research Database (Denmark)

    Seidelin, Ulla Holten; Ibfelt, Else; Andersen, Ingelise

    2016-01-01

    .11–1.67). Conclusion: Early detection in all educational groups might reduce social inequalities in survival, however, the unexplained increased risk for death after adjustment for prognostic factors, warrants increased attention to patients with short education in all age groups throughout treatment......Background: Several studies have documented an association between socioeconomic position and survival from gynaecological cancer, but the mechanisms are unclear. Objective: The aim of this study was to examine the association between level of education and survival after endometrial cancer among...... Danish women; and whether differences in stage at diagnosis and comorbidity contribute to the educational differences in survival. Methods: Women with endometrial cancer diagnosed between 2005 and 2009 were identified in the Danish Gynaecological Cancer Database, with information on clinical...

  15. IMPORTANCE OF DIFFERENT MODELS IN DECISION MAKING, EXPLAINING THE STRATEGIC BEHAVIOR IN ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Cristiano de Oliveira Maciel

    2006-11-01

    Full Text Available This study is about the different models of decision process analyzing the organizational strategy. The article presents the strategy according to a cognitive approach. The discussion about that approach has three models of decision process: rational actor model, organizational behavior, and political model. These models, respectively, present some improvement in the decision making results, search for a good decision facing the cognitive restrictions of the administrator, and lots of talks for making a decision. According to the emphasis of each model, the possibilities for analyzing the strategy are presented. The article also shows that it is necessary to take into account the three different ways of analysis. That statement is justified once the analysis as well as the decision making become more complex, mainly those which are more important for the organizations.

  16. Can commonly measurable traits explain differences in metal accumulation and toxicity in earthworm species?

    Science.gov (United States)

    Qiu, Hao; Peijnenburg, Willie J G M; van Gestel, Cornelis A M; Vijver, Martina G

    2014-01-01

    There is no clear consensus in the literature on the metal accumulation pattern and sensitivity of different earthworm species. In the present study, accumulation and toxicity of Cu, Cd, Ni, and Zn in the earthworms Lumbricus rubellus (epigeic), Aporrectodea longa (anecic), and Eisenia fetida (ultra-epigeic) were determined after 28 days exposure in two soils. Metal accumulation and sensitivity were interpreted using the specific traits of different earthworm species. Results showed that for all four metals tested L. rubellus was the most sensitive species, followed by A. longa and E. fetida. At the same exposure concentration, internal concentrations followed the order: L. rubellus > E. fetida > A. longa for Cu and Ni, L. rubellus ≈ E. fetida ≈ A. longa for Cd, and L. rubellus > A. longa > E. fetida for Zn. Langmuir isotherms were used to model metal accumulation at both nontoxic and toxic exposure concentrations. The Cu, Cd, and Zn concentrations in E. fetida generally leveled off at high exposure concentrations but not for the other two species. A. longa showed a high capability of regulating internal Ni concentrations. The traits-based approaches suggested that most likely a group of earthworm traits together determined (differences in) metal accumulation and sensitivity. More research is needed in this respect to build up solid relationships between species-specific responses and traits, enabling cross-species extrapolation of accumulation and toxicity data.

  17. Explaining differences for Serbia and Slovenia in mathematics achievement in fourth grade

    Directory of Open Access Journals (Sweden)

    Kadijević Đorđe

    2015-01-01

    Full Text Available This paper presents the findings that are parts of a larger international project studying the achievements in mathematics and science for students in primary and lower secondary education. Specifically, we focused on the study of differences in mathematics achievement for Serbian and Slovenian fourth-graders. The study used a sample of 7,861 fourth-grade students from Serbia (N = 3,736 and Slovenia (N = 4,125. The results showed that Serbian students had higher overall achievement and scored higher in both the number content and the knowing cognitive domains, whereas Slovenian students scored higher on the geometry content and the data content domains, also having a higher balance among achievements for both content and cognitive domains. It was also found that Slovenian students had higher self-confidence in learning mathematics. Because there were no other significant differences between Serbia and Slovenia with respect to two other contextual variables and the correlations among these three contextual variables, the explanations of the achievement differences were based upon the consideration of various aspects of curriculum, teaching practice, and teachers' professional development in Serbia and Slovenia. The paper raises the question of educational implications of these findings and the possible directions of improving the quality of mathematics teaching.

  18. The role of the different aspects of academic motivation and competitiveness in explaining self-handicapping

    Directory of Open Access Journals (Sweden)

    Damjan Šimek

    2010-05-01

    Full Text Available In the present research on self-handicapping, the goal was to examine the role of different types of academic motivation according to the level of self-determination. Since the existing research on self-handicapping has examined only the role of interpersonal competition, we also aimed to explore the role of different kinds of competition, i.e., the role of the reasons that motivate people to participate in competition, and the role of the reasons for the avoidance of competition. 748 high school students participated in the study. Regarding the role of academic motivation in self-handicapping the prevailing role of amotivation stood out. Intrinsic motivation predicted self-handicapping negatively, but extrinsic motivation proved to be a positive predictor. The factor structure of the Academic Motivation Scale only enabled differentiation of the reasons for education on the level of three basic types. With regard to the role of the different dimensions of competitiveness in self-handicapping, results show that those denoted by fear of failure and self-worth protection proved to be more characteristic of self-handicapping than those defined by a high valuation of the importance of quality of task accomplishment. Among others, our research suggests that by diverting students away from hypercompetitive values, functionality of self-handicapping can be decreased.

  19. Mapping information exposure on social media to explain differences in HPV vaccine coverage in the United States.

    Science.gov (United States)

    Dunn, Adam G; Surian, Didi; Leask, Julie; Dey, Aditi; Mandl, Kenneth D; Coiera, Enrico

    2017-05-25

    Together with access, acceptance of vaccines affects human papillomavirus (HPV) vaccine coverage, yet little is known about media's role. Our aim was to determine whether measures of information exposure derived from Twitter could be used to explain differences in coverage in the United States. We conducted an analysis of exposure to information about HPV vaccines on Twitter, derived from 273.8 million exposures to 258,418 tweets posted between 1 October 2013 and 30 October 2015. Tweets were classified by topic using machine learning methods. Proportional exposure to each topic was used to construct multivariable models for predicting state-level HPV vaccine coverage, and compared to multivariable models constructed using socioeconomic factors: poverty, education, and insurance. Outcome measures included correlations between coverage and the individual topics and socioeconomic factors; and differences in the predictive performance of the multivariable models. Topics corresponding to media controversies were most closely correlated with coverage (both positively and negatively); education and insurance were highest among socioeconomic indicators. Measures of information exposure explained 68% of the variance in one dose 2015 HPV vaccine coverage in females (males: 63%). In comparison, models based on socioeconomic factors explained 42% of the variance in females (males: 40%). Measures of information exposure derived from Twitter explained differences in coverage that were not explained by socioeconomic factors. Vaccine coverage was lower in states where safety concerns, misinformation, and conspiracies made up higher proportions of exposures, suggesting that negative representations of vaccines in the media may reflect or influence vaccine acceptance. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  20. Differences in sensitivity to deviance partly explain ideological divides in social policy support.

    Science.gov (United States)

    Okimoto, Tyler G; Gromet, Dena M

    2016-07-01

    We propose that political differences in social policy support may be partly driven by the tendency for conservatives to show greater sensitivity to deviance than liberals, even among targets lacking social or functional relevance. In 3 studies, participants were shown geometric figures and were asked to identify the extent to which they were "triangles" (or circles, squares, etc.). More conservative participants reported greater differentiation between perfect and imperfect shapes than more liberal participants, indicating greater sensitivity to deviance. Moreover, shape differentiation partly accounted for the relationship between political ideology and social policy, partially mediating the link between conservatism and harsher punishment of wrongdoers (Studies 1 and 4), less support for public aid for disadvantaged groups (Study 2), and less financial backing for policies that benefit marginalized groups in society (Study 3). This effect was specific to policies that targeted deviant groups (Study 3) and who were not too highly deviant (Study 4). Results suggest that, in addition to commonly cited affective and motivational reactions to deviant actors, political differences in social policy may also be driven by conservatives' greater cognitive propensity to distinguish deviance. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  1. Fire-mediated disruptive selection can explain the reseeder-resprouter dichotomy in Mediterranean-type vegetation.

    Science.gov (United States)

    Altwegg, Res; De Klerk, Helen M; Midgley, Guy F

    2015-02-01

    Crown fire is a key selective pressure in Mediterranean-type plant communities. Adaptive responses to fire regimes involve trade-offs between investment for persistence (fire survival and resprouting) and reproduction (fire mortality, fast growth to reproductive maturity, and reseeding) as investments that enhance adult survival lower growth and reproductive rates. Southern hemisphere Mediterranean-type ecosystems are dominated by species with either endogenous regeneration from adult resprouting or fire-triggered seedling recruitment. Specifically, on nutrient-poor soils, these are either resprouting or reseeding life histories, with few intermediate forms, despite the fact that the transition between strategies is evolutionarily labile. How did this strong dichotomy evolve? We address this question by developing a stochastic demographic model to assess determinants of relative fitness of reseeders, resprouters and hypothetical intermediate forms. The model was parameterised using published demographic data from South African protea species and run over various relevant fire regime parameters facets. At intermediate fire return intervals, trade-offs between investment in growth versus fire resilience can cause fitness to peak at either of the extremes of the reseeder-resprouter continuum, especially when assuming realistic non-linear shapes for these trade-offs. Under these circumstances, the fitness landscape exhibits a saddle which could lead to disruptive selection. The fitness gradient between the peaks was shallow, which may explain why this life-history trait is phylogenetically labile. Resprouters had maximum fitness at shorter fire-return intervals than reseeders. The model suggests that a strong dichotomy in fire survival strategy depends on a non-linear trade-off between growth and fire persistence traits.

  2. A comparison of the psychological refractory period and prioritized processing paradigms: Can the response-selection bottleneck model explain them both?

    Science.gov (United States)

    Miller, Jeff; Durst, Moritz

    2015-10-01

    Four experiments examined whether well-established phenomena from the psychological refractory period (PRP) paradigm are also observed in the prioritized processing paradigm, as would be expected from a common description of the 2 paradigms with the response selection bottleneck (RSB) model. Consistent with a generalization of the RSB model to the prioritized processing paradigm, Experiments 1 and 2 showed that this paradigm yields effects of SOA and stimulus discriminability analogous to those observed in the PRP paradigm. In Experiments 3 and 4, however, overall RTs and effect sizes differed between the PRP and prioritized processing paradigms in ways that are difficult to explain within the RSB model. Understanding the differences between these 2 paradigms offers considerable promise as a way to extend the RSB model beyond the domain of the PRP paradigm and to generalize our understanding of multitasking interference. (c) 2015 APA, all rights reserved).

  3. Differences in the efficacy of climate forcings explained by variations in atmospheric boundary layer depth.

    Science.gov (United States)

    Davy, Richard; Esau, Igor

    2016-05-25

    The Earth has warmed in the last century and a large component of that warming has been attributed to increased anthropogenic greenhouse gases. There are also numerous processes that introduce strong, regionalized variations to the overall warming trend. However, the ability of a forcing to change the surface air temperature depends on its spatial and temporal distribution. Here we show that the efficacy of a forcing is determined by the effective heat capacity of the atmosphere, which in cold and dry climates is defined by the depth of the planetary boundary layer. This can vary by an order of magnitude on different temporal and spatial scales, and so we get a strongly amplified temperature response in shallow boundary layers. This must be accounted for to assess the efficacy of a climate forcing, and also implies that multiple climate forcings cannot be linearly combined to determine the temperature response.

  4. Lifestyle Inequalities: Explaining Socioeconomic Differences in Preventive Practices of Clinically Overweight Women After Menopause.

    Science.gov (United States)

    Audet, Mélisa; Dumas, Alex; Binette, Rachelle; Dionne, Isabelle J

    2017-08-01

    Excess weight and menopause are two major factors increasing aging women's vulnerability to chronic diseases. However, social position and socioeconomic status have also been identified as major determinants influencing both health behaviors and the development of such diseases. This study focuses on the socioeconomic variations of behavioral risk factors of chronic diseases in aging women. By drawing on Bourdieu's sociocultural theory of practice, 40 semistructured interviews were conducted to investigate preventive health practices of clinically overweight, postmenopausal women from contrasting socioeconomic classes living in Canada. Findings emphasize class-based differences with respect to long-term health and preventive practices according to three major themes: priority to long-term time horizons, attention given to risk factors of diseases, and control over future health. Health care providers should strive to work in concert with all subgroups of women to better understand their values, worldviews, and needs to decrease health inequalities after menopause.

  5. The role of attentional resources in explaining sex differences in object location memory.

    Science.gov (United States)

    Barel, Efrat

    2016-10-24

    Sex differences in object location memory have been widely studied, with mixed results. The role of attention in mediating the female advantage in object location memory has not been clearly understood yet. Two experiments, involving 181 participants and using an actual object array, were conducted in the present study to examine two learning conditions: incidental and intentional. In each experiment, participants were randomly assigned to divided versus full attention conditions. The study also examined memorizing location-maintained and location-exchanged objects. In both experiments, in both incidental and intentional learning conditions, women outperformed men in memorizing location-exchanged objects in the full but not in the divided attention condition. These findings confirm and extend previous ones concerning the conditions under which the female advantage in the detection of change in an array of objects occurs. The findings are discussed within an evolutionary conceptual framework. © 2016 International Union of Psychological Science.

  6. Psychological Sex Differences: Origins through Sexual Selection.

    Science.gov (United States)

    Buss, David M.

    1995-01-01

    Outlines an explanatory framework for psychological sex differences, one that is anchored in the new theoretical paradigm of evolutionary psychology. This paradigm rejects the dichotomy between biology and environment and provides a new metatheory of why sex differences exist, where they exist, and in what contexts they are expressed. (GR)

  7. In vitro Increased Respiratory Activity of Selected Oral Bacteria May Explain Competitive and Collaborative Interactions in the Oral Microbiome

    Science.gov (United States)

    Hernandez-Sanabria, Emma; Slomka, Vera; Herrero, Esteban R.; Kerckhof, Frederiek-Maarten; Zaidel, Lynette; Teughels, Wim; Boon, Nico

    2017-01-01

    Understanding the driving forces behind the shifts in the ecological balance of the oral microbiota will become essential for the future management and treatment of periodontitis. As the use of competitive approaches for modulating bacterial outgrowth is unexplored in the oral ecosystem, our study aimed to investigate both the associations among groups of functional compounds and the impact of individual substrates on selected members of the oral microbiome. We employed the Phenotype Microarray high-throughput technology to analyse the microbial cellular phenotypes of 15 oral bacteria. Multivariate statistical analysis was used to detect respiratory activity triggers and to assess similar metabolic activities. Carbon and nitrogen were relevant for the respiration of health-associated bacteria, explaining competitive interactions when grown in biofilms. Carbon, nitrogen, and peptides tended to decrease the respiratory activity of all pathobionts, but not significantly. None of the evaluated compounds significantly increased activity of pathobionts at both 24 and 48 h. Additionally, metabolite requirements of pathobionts were dissimilar, suggesting that collective modulation of their respiratory activity may be challenging. Flow cytometry indicated that the metabolic activity detected in the Biolog plates may not be a direct result of the number of bacterial cells. In addition, damage to the cell membrane may not influence overall respiratory activity. Our methodology confirmed previously reported competitive and collaborative interactions among bacterial groups, which could be used either as marker of health status or as targets for modulation of the oral environment. PMID:28638806

  8. In vitro Increased Respiratory Activity of Selected Oral Bacteria May Explain Competitive and Collaborative Interactions in the Oral Microbiome

    Directory of Open Access Journals (Sweden)

    Emma Hernandez-Sanabria

    2017-06-01

    Full Text Available Understanding the driving forces behind the shifts in the ecological balance of the oral microbiota will become essential for the future management and treatment of periodontitis. As the use of competitive approaches for modulating bacterial outgrowth is unexplored in the oral ecosystem, our study aimed to investigate both the associations among groups of functional compounds and the impact of individual substrates on selected members of the oral microbiome. We employed the Phenotype Microarray high-throughput technology to analyse the microbial cellular phenotypes of 15 oral bacteria. Multivariate statistical analysis was used to detect respiratory activity triggers and to assess similar metabolic activities. Carbon and nitrogen were relevant for the respiration of health-associated bacteria, explaining competitive interactions when grown in biofilms. Carbon, nitrogen, and peptides tended to decrease the respiratory activity of all pathobionts, but not significantly. None of the evaluated compounds significantly increased activity of pathobionts at both 24 and 48 h. Additionally, metabolite requirements of pathobionts were dissimilar, suggesting that collective modulation of their respiratory activity may be challenging. Flow cytometry indicated that the metabolic activity detected in the Biolog plates may not be a direct result of the number of bacterial cells. In addition, damage to the cell membrane may not influence overall respiratory activity. Our methodology confirmed previously reported competitive and collaborative interactions among bacterial groups, which could be used either as marker of health status or as targets for modulation of the oral environment.

  9. Large variation in glyphosate mineralization in 21 different agricultural soils explained by soil properties.

    Science.gov (United States)

    Nguyen, Nghia Khoi; Dörfler, Ulrike; Welzl, Gerhard; Munch, Jean Charles; Schroll, Reiner; Suhadolc, Marjetka

    2018-01-30

    Glyphosate and its main metabolite aminomethylphosphonic acid (AMPA) have frequently been detected in surface water and groundwaters. Since adequate glyphosate mineralization in soil may reduce its losses to environment, improved understanding of site specific factors underlying pesticide mineralization in soils is needed. The aim of this study was to investigate the relationship between soil properties and glyphosate mineralization. To establish a sound basis for resilient correlations, the study was conducted with a large number of 21 agricultural soils, differing in a variety of soil parameters, such as soil texture, soil organic matter content, pH, exchangeable ions etc. The mineralization experiments were carried out with 14 C labelled glyphosate at a soil water tension of -15 kPa and at a soil density of 1.3 g cm -3 at 20 ± 1 °C for an incubation period of 32 days. The results showed that the mineralization of glyphosate in different agricultural soils varied to a great extent, from 7 to 70% of the amount initially applied. Glyphosate mineralization started immediately after application, the highest mineralization rates were observed within the first 4 days in most of the 21 soils. Multiple regression analysis revealed exchangeable acidity (H + and Al 3+ ), exchangeable Ca 2+ ions and ammonium lactate extractable K to be the key soil parameters governing glyphosate mineralization in the examined soils. A highly significant negative correlation between mineralized glyphosate and NaOH-extractable residues (NaOH-ER) in soils strongly suggests that NaOH-ER could be used as a simple and reliable parameter for evaluating the glyphosate mineralization capacity. The NaOH-ER were composed of glyphosate, unknown 14 C-residues, and AMPA (12%-65%, 3%-34%, 0%-11% of applied 14 C, respectively). Our results highlighted the influential role of soil exchangeable acidity, which should therefore be considered in pesticide risk assessments and management to

  10. Gaps in knowledge: tracking and explaining gender differences in health information seeking.

    Science.gov (United States)

    Manierre, Matthew J

    2015-03-01

    Self-directed health information seeking has become increasingly common in recent years, yet there is a substantial body of evidence suggesting that females are more likely to engage in information seeking than males. Previous research has largely ignored the significance of this difference as both an empirical and a theoretical finding. The current study has two goals, seeking to track this sex gap over time and to test explanations for its existence. The three explanations tested are based in past findings of gendered division of childcare labor, gendered reactivity to illness, and gendered perceived risk of illness. These were tested using multiple dependent variables from both repeated cross sectional data and 2012 data from the Health Information Trends Survey (HINTS). Results show that females are significantly more likely to look for cancer information, information in general, and information over the Internet over time than males, though the gap may be closing in the case of cancer information. The three explanations also received little clear support though perceived risk of getting cancer acted as a mediator through which men may be less likely to look for cancer information. Based on this analysis it is clear that a sex gap in information seeking is present and theories of masculinity and health may hold promise in some contexts but additional explanations are needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Inactive xylem can explain differences in calibration factors for thermal dissipation probe sap flow measurements.

    Science.gov (United States)

    Paudel, Indira; Kanety, Tal; Cohen, Shabtai

    2013-09-01

    Thermal dissipation probes (TDPs) were calibrated in three diffuse porous fruit trees and one ornamental species in the field by comparison with heat pulse probes (nectarine and persimmon), in a greenhouse on lysimeters (apple and persimmon) and in the laboratory by pushing water through cut branches (apple, Peltophorum and nectarine). Two operational methods were used: continuous (constant thermal dissipation, CTD) and discontinuous, or transient, heating (transient thermal dissipation, TTD). Correction for the radial distribution of sap flux density was with an analytical function derived from a linear decrease in flux density with depth, as measured with a multi-depth 'Tmax' heat pulse system. When analyzed with previous calibration factors, the measured sap flow was sap flow using heat dissipation probes. Tree Physiol 1999;19:681-687) almost completely compensated for the underestimations. Calibrations are given for each species both before and after corrections of temperature differentials, along with a multispecies calibration. These results should be an important step in reconciling many reports of different calibration factors for TDP probes.

  12. A process view on implementing an antibullying curriculum: How teachers differ and what explains the variation.

    Science.gov (United States)

    Haataja, Anne; Ahtola, Annarilla; Poskiparta, Elisa; Salmivalli, Christina

    2015-12-01

    The present study provides a person-centered view on teachers' adherence to the KiVa antibullying curriculum over a school year. Factor mixture modeling was used to examine how teachers (N = 282) differed in their implementation profiles and multinomial logistic regression was used to identify factors related to these profiles. On the basis of lesson adherence across time, 3 types of implementers emerged: (a) high implementers (53%) started at a very high level and remained so over time, (b) moderate implementers (30%) consistently utilized more than half of the lesson material, and (c) surrenders (17%) started at a high level that soon declined. Teachers' beliefs toward program effectiveness were positively associated with starting at higher levels of fidelity (high and surrenders), whereas principal support for antibullying work predicted maintaining the initial level of implementation over the school year (high and moderate). Finally, good lesson preparation and student engagement were associated with a higher levels of implementation throughout the school year (the high group). Neither participation in preimplementation training nor classroom management skills were related to 3 implementation profiles. The findings highlight the importance of individual and interpersonal factors for successful implementation of school-based bullying prevention programs. (c) 2015 APA, all rights reserved).

  13. Can genetic differences explain vocal dialect variation in sperm whales, Physeter macrocephalus?

    Science.gov (United States)

    Rendell, Luke; Mesnick, Sarah L; Dalebout, Merel L; Burtenshaw, Jessica; Whitehead, Hal

    2012-03-01

    Sperm whale social groups can be assigned to vocal clans based on their production of codas, short stereotyped patterns of clicks. It is currently unclear whether genetic variation could account for these behavioural differences. We studied mitochondrial DNA (mtDNA) variation among sympatric vocal clans in the Pacific Ocean, using sequences extracted from sloughed skin samples. We sampled 194 individuals from 30 social groups belonging to one of three vocal clans. As in previous studies of sperm whales, mtDNA control region diversity was low (π = 0.003), with just 14 haplotypes present in our sample. Both hierarchical AMOVAs and partial Mantel tests showed that vocal clan was a more important factor in matrilineal population genetic structure than geography, even though our sampling spanned thousands of kilometres. The variance component attributed to vocal dialects (7.7%) was an order of magnitude higher than those previously reported in birds, while the variance component attributed to geographic area was negligible. Despite this, the two most common haplotypes were present in significant quantities in each clan, meaning that variation in the control region cannot account for behavioural variation between clans, and instead parallels the situation in humans where parent-offspring transmission of language variation has resulted in correlations with neutral genes. Our results also raise questions for the management of sperm whale populations, which has traditionally been based on dividing populations into geographic 'stocks', suggesting that culturally-defined vocal clans may be more appropriate management units.

  14. Aerobic Fitness Explains Individual Differences in the Functional Brain Connectome of Healthy Young Adults.

    Science.gov (United States)

    Talukdar, Tanveer; Nikolaidis, Aki; Zwilling, Chris E; Paul, Erick J; Hillman, Charles H; Cohen, Neal J; Kramer, Arthur F; Barbey, Aron K

    2017-09-14

    A wealth of neuroscience evidence demonstrates that aerobic fitness enhances structural brain plasticity, promoting the development of gray matter volume and maintenance of white matter integrity within networks for executive function, attention, learning, and memory. However, the role of aerobic fitness in shaping the functional brain connectome remains to be established. The present work therefore investigated the effects of aerobic fitness (as measured by VO2max) on individual differences in whole-brain functional connectivity assessed from resting state fMRI data. Using a connectome-wide association study, we identified significant brain-fitness relationships within a large sample of healthy young adults (N = 242). The results revealed several regions within frontal, temporal, parietal, and cerebellar cortex, having significant association with aerobic fitness. We further characterized the influence of these regions on 7 intrinsic connectivity networks, demonstrating the greatest association with networks that are known to mediate the beneficial effects of aerobic fitness on executive function (frontoparietal network), attention and learning (dorsal and ventral attention network), and memory (default mode network). In addition, we provide evidence that connectivity strength between these regions and the frontoparietal network is predictive of individuals' fluid intelligence. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Musical rhythm discrimination explains individual differences in grammar skills in children.

    Science.gov (United States)

    Gordon, Reyna L; Shivers, Carolyn M; Wieland, Elizabeth A; Kotz, Sonja A; Yoder, Paul J; Devin McAuley, J

    2015-07-01

    This study considered a relation between rhythm perception skills and individual differences in phonological awareness and grammar abilities, which are two language skills crucial for academic achievement. Twenty-five typically developing 6-year-old children were given standardized assessments of rhythm perception, phonological awareness, morpho-syntactic competence, and non-verbal cognitive ability. Rhythm perception accounted for 48% of the variance in morpho-syntactic competence after controlling for non-verbal IQ, socioeconomic status, and prior musical activities. Children with higher phonological awareness scores were better able to discriminate complex rhythms than children with lower scores, but not after controlling for IQ. This study is the first to show a relation between rhythm perception skills and morpho-syntactic production in children with typical language development. These findings extend the literature showing substantial overlap of neurocognitive resources for processing music and language. A video abstract of this article can be viewed at: http://youtu.be/_lO692qHDNg. © 2014 John Wiley & Sons Ltd.

  16. The "narcissism of minor differences" theory: Can it explain ethnic conflict?

    Directory of Open Access Journals (Sweden)

    Kolstø Pål

    2007-01-01

    Full Text Available In many ethnic conflicts and civil wars in the 20th century the cultural differences between the warring groups were very small. The bloody conflicts between Serbs, Croatians, and Bosnians during the breakup of Yugoslavia are a case in point. This observation has led some commentators to conclude that a lack of objective cultural markers between groups may itself be conducive to violence: When the members of two groups are difficult to tell apart, violence is inserted in order to create identity boundaries between them. One particular version of this theory goes under the name ‘narcissism of minor differences’. This expression goes back to Sigmund Freud, who applied it both to individual psychology and in his philosophy of culture. The notion has been largely ignored by practicing psychotherapists, but over the last decades, however, it has been discovered by journalists and social scientists and applied to cases of collective rather than individual violence. The present article examines some of the articles and books that expound the ‘the narcissism of minor differences’-concept in order to assess the explanatory strength and weaknesses of this theory. .

  17. Can Trust In Traditional News Media Explain Cross-National Differences In News Exposure Of Young People Online?

    OpenAIRE

    Elvestad, Eiri; Phillips, Angela; Feuerstein, Mira

    2017-01-01

    Using data from a cross-national survey (N = 940) and from in-depth interviews with 37 studentsin Israel, Norway and the United Kingdom, we discuss how in different political and 10 news media environments young people’s trust in traditional media can explain their news exposure online. This study shows there are some similarities, but also major cross-national differences, between young people in how they trust, are exposed to and find different news sources usable for information about thei...

  18. Application of an Integrated GPCR SAR-Modeling Platform To Explain the Activation Selectivity of Human 5-HT2C over 5-HT2B.

    Science.gov (United States)

    Heifetz, Alexander; Storer, R Ian; McMurray, Gordon; James, Tim; Morao, Inaki; Aldeghi, Matteo; Bodkin, Mike J; Biggin, Philip C

    2016-05-20

    Agonism of the 5-HT2C serotonin receptor has been associated with the treatment of a number of diseases including obesity, psychiatric disorders, sexual health, and urology. However, the development of effective 5-HT2C agonists has been hampered by the difficulty in obtaining selectivity over the closely related 5-HT2B receptor, agonism of which is associated with irreversible cardiac valvulopathy. Understanding how to design selective agonists requires exploration of the structural features governing the functional uniqueness of the target receptor relative to related off targets. X-ray crystallography, the major experimental source of structural information, is a slow and challenging process for integral membrane proteins, and so is currently not feasible for every GPCR or GPCR-ligand complex. Therefore, the integration of existing ligand SAR data with GPCR modeling can be a practical alternative to provide this essential structural insight. To demonstrate this, we integrated SAR data from 39 azepine series 5-HT2C agonists, comprising both selective and unselective examples, with our hierarchical GPCR modeling protocol (HGMP). Through this work we have been able to demonstrate how relatively small differences in the amino acid sequences of GPCRs can lead to significant differences in secondary structure and function, as supported by experimental data. In particular, this study suggests that conformational differences in the tilt of TM7 between 5-HT2B and 5-HT2C, which result from differences in interhelical interactions, may be the major source of selectivity in G-protein activation between these two receptors. Our approach also demonstrates how the use of GPCR models in conjunction with SAR data can be used to explain activity cliffs.

  19. Can chronic multimorbidity explain the age-related differences in strength, speed and balance in older adults?

    Science.gov (United States)

    Welmer, Anna-Karin; Kåreholt, Ingemar; Angleman, Sara; Rydwik, Elisabeth; Fratiglioni, Laura

    2012-10-01

    It is known that physical performance declines with age in general, however there remains much to be understood in terms of age-related differences amongst older adults across a variety of physical components (such as speed, strength and balance), and particularly in terms of the role played by multimorbidity of chronic diseases. We aimed to detect the age-related differences across four components of physical performance and to explore to what extent chronic diseases and multimorbidity may explain such differences. We analyzed cross-sectional data from a population-based sample of 3323 people, aged 60 years and older from the SNAC-K study, Stockholm, Sweden. Physical performance was assessed by trained nurses using several tests (grip strength, walking speed, balance and chair stands). Clinical diagnoses were made by the examining physician based on clinical history and examination. Censored normal regression analyses showed that the 72-90+ year-old persons had 17-40% worse grip strength, 44-86% worse balance, 30-86% worse chair stand score, and 21-59% worse walking speed, compared with the 60-66 year-old persons. Chronic diseases were strongly associated with physical impairment, and this association was particularly strong among the younger men. However, chronic diseases explained only some of the age-related differences in physical performance. When controlling for chronic diseases in the analyses, the age-related differences in physical performance changed 1-11%. In spite of the strong association between multimorbidity and physical impairment, chronic morbidities explained only a small part of the age-related differences in physical performance.

  20. Two different mechanisms support selective attention at different phases of training

    Science.gov (United States)

    Cha, Kexin; Byers, Anna; Serences, John T.

    2017-01-01

    Selective attention supports the prioritized processing of relevant sensory information to facilitate goal-directed behavior. Studies in human subjects demonstrate that attentional gain of cortical responses can sufficiently account for attention-related improvements in behavior. On the other hand, studies using highly trained nonhuman primates suggest that reductions in neural noise can better explain attentional facilitation of behavior. Given the importance of selective information processing in nearly all domains of cognition, we sought to reconcile these competing accounts by testing the hypothesis that extensive behavioral training alters the neural mechanisms that support selective attention. We tested this hypothesis using electroencephalography (EEG) to measure stimulus-evoked visual responses from human subjects while they performed a selective spatial attention task over the course of ~1 month. Early in training, spatial attention led to an increase in the gain of stimulus-evoked visual responses. Gain was apparent within ~100 ms of stimulus onset, and a quantitative model based on signal detection theory (SDT) successfully linked the magnitude of this gain modulation to attention-related improvements in behavior. However, after extensive training, this early attentional gain was eliminated even though there were still substantial attention-related improvements in behavior. Accordingly, the SDT-based model required noise reduction to account for the link between the stimulus-evoked visual responses and attentional modulations of behavior. These findings suggest that training can lead to fundamental changes in the way attention alters the early cortical responses that support selective information processing. Moreover, these data facilitate the translation of results across different species and across experimental procedures that employ different behavioral training regimes. PMID:28654635

  1. Self-reported harassment and bullying in Australian universities: explaining differences between regional, metropolitan and elite institutions

    DEFF Research Database (Denmark)

    Skinner, Timothy C.; Peetz, David; Strachan, Glenda

    2015-01-01

    of harassment. This probably reflected the labour market and resource context of regional universities. Binary logistic regression indicated that a perceived lack of support for professional development partially explained the effect of regional status on differences in the rates of harassment/bullying across......© 2015 Association for Tertiary Education Management and the LH Martin Institute for Tertiary Education Leadership and Management. We analyse data from the largest survey of university staff in Australia to determine whether bullying and harassment are more common in regional than metropolitan...... university types. Markers of organisational culture only partially account for differences in the rates of harassment/bullying between university types....

  2. Immune Investment Is Explained by Sexual Selection and Pace-of-Life, but Not Longevity in Parrots (Psittaciformes)

    Science.gov (United States)

    Edwards, Darryl B.

    2012-01-01

    Investment in current reproduction should come at the expense of traits promoting future reproduction, such as immunity and longevity. To date, comparative studies of pace-of-life traits have provided some support for this, with slower paced species having greater immune function. Another means of investment in current reproduction is through secondary sexual characters (SSC). Investment in SSC's is considered costly, both in terms of immunity and longevity, with greater costs being borne by species with more elaborate traits. Yet within species, females prefer more ornate males and those males are typically immunologically superior. Because of this, predictions about the relationship between immunity and SSC's across species are not clear. If traits are costly, brighter species should have reduced immune function, but the opposite is true if SSC's arise from selection for more immunocompetent individuals. My approach was to investigate immune investment in relation to SSC's, pace-of-life and longevity while considering potentially confounding ecological factors. To do so I assessed leukocyte counts from in a novel group, the Psittaciformes. Investment in SSC's best explained investment in immunity: species with brighter plumage had higher leukocyte counts and those with a greater degree of sexual dichromatism had fewer. Ecological variables and pace-of-life models tended to be poor predictors of immune investment. However, shorter incubation periods were associated with lower leukocyte counts supporting the notion that species with a fast pace-of-life invest less in immunity. These results suggest that investment in reproduction in terms of fast pace-of-life and sexual dichromatism results in reduced immunity; however, investment in plumage colour per se does not impose a cost on immunity across species. PMID:23300862

  3. Immune investment is explained by sexual selection and pace-of-life, but not longevity in parrots (Psittaciformes.

    Directory of Open Access Journals (Sweden)

    Darryl B Edwards

    Full Text Available Investment in current reproduction should come at the expense of traits promoting future reproduction, such as immunity and longevity. To date, comparative studies of pace-of-life traits have provided some support for this, with slower paced species having greater immune function. Another means of investment in current reproduction is through secondary sexual characters (SSC. Investment in SSC's is considered costly, both in terms of immunity and longevity, with greater costs being borne by species with more elaborate traits. Yet within species, females prefer more ornate males and those males are typically immunologically superior. Because of this, predictions about the relationship between immunity and SSC's across species are not clear. If traits are costly, brighter species should have reduced immune function, but the opposite is true if SSC's arise from selection for more immunocompetent individuals. My approach was to investigate immune investment in relation to SSC's, pace-of-life and longevity while considering potentially confounding ecological factors. To do so I assessed leukocyte counts from in a novel group, the Psittaciformes. Investment in SSC's best explained investment in immunity: species with brighter plumage had higher leukocyte counts and those with a greater degree of sexual dichromatism had fewer. Ecological variables and pace-of-life models tended to be poor predictors of immune investment. However, shorter incubation periods were associated with lower leukocyte counts supporting the notion that species with a fast pace-of-life invest less in immunity. These results suggest that investment in reproduction in terms of fast pace-of-life and sexual dichromatism results in reduced immunity; however, investment in plumage colour per se does not impose a cost on immunity across species.

  4. Energy storage and fecundity explain deviations from ecological stoichiometry predictions under global warming and size-selective predation.

    Science.gov (United States)

    Zhang, Chao; Jansen, Mieke; De Meester, Luc; Stoks, Robby

    2016-11-01

    A key challenge for ecologists is to predict how single and joint effects of global warming and predation risk translate from the individual level up to ecosystem functions. Recently, stoichiometric theory linked these levels through changes in body stoichiometry, predicting that both higher temperatures and predation risk induce shifts in energy storage (increases in C-rich carbohydrates and reductions in N-rich proteins) and body stoichiometry (increases in C : N and C : P). This promising theory, however, is rarely tested and assumes that prey will divert energy away from reproduction under predation risk, while under size-selective predation, prey instead increase fecundity. We exposed the water flea Daphnia magna to 4 °C warming and fish predation risk to test whether C-rich carbohydrates increase and N-rich proteins decrease, and as a result, C : N and C : P increase under warming and predation risk. Unexpectedly, warming decreased body C : N, which was driven by reductions in C-rich fat and sugar contents while the protein content did not change. This reflected a trade-off where the accelerated intrinsic growth rate under warming occurred at the cost of a reduced energy storage. Warming reduced C : N less and only increased C : P and N : P in the fish-period Daphnia. These evolved stoichiometric responses to warming were largely driven by stronger warming-induced reductions in P than in C and N and could be explained by the better ability to deal with warming in the fish-period Daphnia. In contrast to theory predictions, body C : N decreased under predation risk due to a strong increase in the N-rich protein content that offsets the increase in C-rich fat content. The higher investment in fecundity (more N-rich eggs) under predation risk contributed to this stronger increase in protein content. Similarly, the lower body C : N of pre-fish Daphnia also matched their higher fecundity. Warming and predation risk independently shaped body

  5. Gender identity better than sex explains individual differences in episodic and semantic components of autobiographical memory and future thinking.

    Science.gov (United States)

    Compère, Laurie; Rari, Eirini; Gallarda, Thierry; Assens, Adèle; Nys, Marion; Coussinoux, Sandrine; Machefaux, Sébastien; Piolino, Pascale

    2018-01-01

    A recently tested hypothesis suggests that inter-individual differences in episodic autobiographical memory (EAM) are better explained by individual identification of typical features of a gender identity than by sex. This study aimed to test this hypothesis by investigating sex and gender related differences not only in EAM but also during retrieval of more abstract self-knowledge (i.e., semantic autobiographical memory, SAM, and conceptual self, CS), and considering past and future perspectives. No sex-related differences were identified, but regardless of the sex, feminine gender identity was associated with clear differences in emotional aspects that were expressed in both episodic and more abstract forms of AM, and in the past and future perspectives, while masculine gender identity was associated with limited effects. In conclusion, our results support the hypothesis that inter-individual differences in AM are better explained by gender identity than by sex, extending this assumption to both episodic and semantic forms of AM and future thinking. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Explaining between-race differences in African-American and European-American women's responses to breast density notification.

    Science.gov (United States)

    Manning, Mark; Albrecht, Terrance L; Yilmaz-Saab, Zeynep; Penner, Louis; Norman, Andria; Purrington, Kristen

    2017-12-01

    Prior research shows between-race differences in women's knowledge and emotions related to having dense breasts, thus suggesting that between-race differences in behavioral decision-making following receipt of breast density (BD) notifications are likely. Guided by the theory of planned behavior, this study examined differences in emotion-related responses (i.e., anxiety, worry, confusion) and behavioral cognition (e.g., intentions, behavioral attitudes) following receipt of BD notifications among African American (AA) and European American (EA) women. This study also examined whether race-related perceptions (i.e., discrimination, group-based medical mistrust), relevant knowledge and socioeconomic status (SES) explained the between race differences. Michigan women (N = 457) who presented for routine screening mammogram and had dense breasts, no prior breast cancer diagnoses, and had screen-negative mammograms were recruited from July, 2015 to March 2016. MANOVA was used to examine between race differences in psychological responses (i.e., emotional responses and behavioral cognition), and a multi-group structural regression model was used to examine whether race-related constructs, knowledge and SES mediated the effect of race on emotional responses and behavioral cognition. Prior awareness of BD was accounted for in all analyses. AA women generally reported more negative psychological responses to receiving BD notifications regardless of prior BD awareness. AA women had more favorable perceptions related to talking to their physicians about the BD notifications. Generally, race-related perceptions, SES, and related knowledge partially accounted for the effect of race on psychological response. Race-related perceptions and SES partially accounted for the differences in behavioral intentions. Between-race differences in emotional responses to BD notifications did not explain differences in women's intentions to discuss BD notifications with their physicians

  7. Variable beta-glucans production by different states of Eurotium amstelodami explains differences in inflammatory responses in airway cells.

    Science.gov (United States)

    Bellanger, Anne-Pauline; Millon, Laurence; Rognon, Bénédicte; Roussel, Sandrine; Botterel, Françoise; Bretagne, Stéphane; Reboux, Gabriel

    2011-09-01

    Eurotium amstelodami, a mold frequently identified in housing and farm air samples, is a suspected cause of respiratory diseases such as allergic alveolitis, atopic asthma, and organic dust toxic syndrome. This fungus is present in the air in three different states (ascospores, conidia, and hyphae). The aim of this study was to test in vitro the differential inflammatory response of airway cells exposed to 1,3 betaglucanase-treated protein extract (BGPE), from E. amstelodami ascospores, conidia, and hyphae. Confluent cells from the A549 cell line were inoculated with calibrated BGPE issued from the three fungal forms. The levels of eight cytokines and chemokines involved in inflammatory responses were measured after 8 h of exposure. Beta-d-glucan (BDG) was quantified in total fungal extract as well as in the BGPE from the three fungal states. Hyphal BGPE were the only ones to induce a marked inflammatory response and they contain higher quantities of BDG. The present study adds to the growing body of evidence that beta-glucan from fungal hyphae play a crucial role in respiratory diseases. © 2011 The Authors. APMIS © 2011 APMIS.

  8. External root resorption: Different etiologies explained from the composition of the human root-close periodontal membrane

    Directory of Open Access Journals (Sweden)

    Inger Kjaer

    2013-01-01

    Full Text Available Introduction: This paper summarizes different conditions, which have a well-known influence on the resorption of tooth roots. It also highlights factors important for individual susceptibility to root resorption. Furthermore, the paper focuses on idiopathic root resorption where the provoking factor is not known. The Hypothesis: The several different disturbances causing root resorption can be either orthodontically provoked or acquired by trauma, virus or congenital diseases. It is presumed that all these conditions lead to inflammatory processes in the three main tissue layers, comprising the peri-root sheet. Evaluation of the Hypothesis: This paper explains how different etiologies behind root resorption and how different phenotypic traits in root resorption can be understood from immunohistochemical studies of the human periodontal membrane close to the root and thus, gain a new understanding of the phenomenon of root resorption.

  9. Ethnic Differences in Arterial Wave Reflection Are Mostly Explained by Differences in Body Height - Cross-Sectional Analysis of the HELIUS Study.

    Directory of Open Access Journals (Sweden)

    Daan W Eeftinck Schattenkerk

    Full Text Available Differences in arterial wave reflection and central blood pressure (BP have been associated with cardiovascular disease (CVD in various populations and may contribute to ethnic differences in CVD. Whether ethnic differences in wave reflection and central BP can be explained by conventional risk factors for CVD or may result from physiological differences remains undetermined.We examined ethnic differences in augmentation index (AIx and central systolic BP and their determinants in a large multi-ethnic cohort study in Amsterdam, the Netherlands. A total of 8812 (46% male participants aged 18-70 years of Dutch, South-Asian Surinamese, African Surinamese and Ghanaian origin were included. AIx and central BP were measured in duplicate using the Arteriograph system.AIx and central systolic BP were significantly higher in South-Asian Surinamese (35±17%, 126±22 mmHg, African Surinamese (33±17%, 129±23 mmHg and Ghanaian (33±16%, 135±24 mmHg as compared with Dutch (27±17%, 118±20 mmHg, all p<0.001. Correction for cardiovascular risk factors only slightly reduced the difference in AIx, whereas correction for body height attenuated age and gender corrected ethnic differences in AIx the most. Differences in central systolic BP were primarily determined by differences in AIx for South-Asian Surinamese and by differences in peripheral systolic BP for subjects of African origin.Substantial differences in AIx and central BP exist across different ethnic groups that cannot be explained by differences in conventional risk factors for CVD. These findings may explain part of the underestimation of cardiovascular risk observed in populations of African and South-Asian descent.

  10. Are racial differences in patient-physician cancer communication and information explained by background, predisposing, and enabling factors?

    Science.gov (United States)

    Manfredi, Clara; Kaiser, Karen; Matthews, Alicia K; Johnson, Timothy P

    2010-04-01

    Research shows that African Americans tend to have poorer and less informative patient-physician communication than Whites. We analyzed survey data from 248 African American and 244 White cancer patients to examine whether this disadvantage could be explained by race variability on several other variables commonly reported to affect communication. These variables were organized into background, enabling, and predisposing factors, based on the Precede-Proceed Model. Multivariate regressions were used to test whether race differences in communication and information variables persisted after successively controlling for background, enabling, and predisposing factors. African American patients had higher interpersonal communication barriers than Whites, but this difference did not persist after controlling for background factors. African Americans also had higher unmet information needs and were less likely to receive the name of a cancer expert. These differences persisted after controlling for all other factors. Future research should focus on the informational disadvantages of African American patients and how such disadvantages may affect cancer treatment decisions.

  11. Can food specialization by individual Oystercatchers Haematopus ostralegus be explained by differences in prey specific handling efficiencies?

    NARCIS (Netherlands)

    Wanink, JH; Zwarts, L

    1996-01-01

    Three individually-tested adult Oystercatchers took different proportions of shallow-buried bivalves Mya arenaria and Scrobicularia plana from a mixture on offer in an experimental situation. Two birds, taking mainly or exclusively Scrobicularia, selected the species as predicted by a random search

  12. Comment on Gohli et al. : "Does promiscuity explain differences in levels of genetic diversity across passerine birds?"

    NARCIS (Netherlands)

    Spurgin, Lewis G.

    2013-01-01

    Gohli et al. (2013) report a positive relationship between genetic diversity and promiscuity across passerine birds, and suggest that female promiscuity acts as a form of balancing selection, maintaining differences in genetic variation across species. This is an interesting hypothesis, but the

  13. Explaining the link between objective and perceived differences in groups: The role of the belonging and distinctiveness motives.

    Science.gov (United States)

    Ormiston, Margaret E

    2016-02-01

    Group diversity research often focuses on objective diversity, or the actual compositional attributes of the group (e.g., differences in sex or functional background), and its impact on group processes and performance. More recently, diversity researchers have called for consideration of group members' perceptions of diversity, or their subjective understanding of differences within their group, because these perceptions have important effects on group outcomes. In fact, research has indicated only a modest correlation between objective and perceived diversity. Although the subjective nature of group diversity has important implications for group outcomes, we are still unclear about why and when perceived diversity diverges from objective diversity. In this article, I examine the role of identity motives, or motives that guide self-definition, in shaping member's perceptions of themselves and their group's composition. I argue that group members want to balance their needs for belonging and distinctiveness, but high levels of objective differences make them feel too distinct whereas low levels of objective differences makes them feel too deindividuated. Individual differences in the need to belong and be distinct further influence the degree to which these motives are satisfied. In turn, when these motives are unsatisfied, they will affect members' perceptions of differences. The presented theory helps to explain the discrepancy between objective differences and members' perceptions of differences, and ultimately helps integrate opposing findings in the diversity literature. (c) 2016 APA, all rights reserved).

  14. SPSS explained

    CERN Document Server

    Hinton, Perry R; Brownlow, Charlotte

    2014-01-01

    SPSS Explained provides the student with all that they need to undertake statistical analysis using SPSS. It combines a step-by-step approach to each procedure with easy to follow screenshots at each stage of the process. A number of other helpful features are provided: regular advice boxes with tips specific to each test explanations divided into 'essential' and 'advanced' sections to suit readers at different levels frequently asked questions at the end of each chapter. The first edition of this popular book has been fully updated for IBM SPSS version 21 and also includes: chapters that expl

  15. Sex differences, sexual selection, and ageing: an experimental evolution approach.

    Science.gov (United States)

    Maklakov, Alexei A; Bonduriansky, Russell; Brooks, Robert C

    2009-10-01

    Life-history (LH) theory predicts that selection will optimize the trade-off between reproduction and somatic maintenance. Reproductive ageing and finite life span are direct consequences of such optimization. Sexual selection and conflict profoundly affect the reproductive strategies of the sexes and thus can play an important role in the evolution of life span and ageing. In theory, sexual selection can favor the evolution of either faster or slower ageing, but the evidence is equivocal. We used a novel selection experiment to investigate the potential of sexual selection to influence the adaptive evolution of age-specific LH traits. We selected replicate populations of the seed beetle Callosobruchus maculatus for age at reproduction ("Young" and "Old") either with or without sexual selection. We found that LH selection resulted in the evolution of age-specific reproduction and mortality but these changes were largely unaffected by sexual selection. Sexual selection depressed net reproductive performance and failed to promote adaptation. Nonetheless, the evolution of several traits differed between males and females. These data challenge the importance of current sexual selection in promoting rapid adaptation to environmental change but support the hypothesis that sex differences in LH-a historical signature of sexual selection-are key in shaping trait responses to novel selection.

  16. Explaining Differences Between Bioaccumulation Measurements in Laboratory and Field Data Through Use of a Probabilistic Modeling Approach

    DEFF Research Database (Denmark)

    Selck, Henriette; Drouillard, Ken; Eisenreich, Karen

    2012-01-01

    In the regulatory context, bioaccumulation assessment is often hampered by substantial data uncertainty as well as by the poorly understood differences often observed between results from laboratory and field bioaccumulation studies. Bioaccumulation is a complex, multifaceted process, which calls...... the role of sediment components (black carbon, labile organic matter, and the like) on chemical absorption efficiencies has been identified as a key next steps...... bioaccumulation for 4 species and 2 chemicals, to assess whether uncertainty in these factors can explain the observed differences among laboratory and field studies. The organisms evaluated in simulations including mayfly larvae, deposit-feeding polychaetes, yellow perch, and little owl represented a range...... components. Improvements in the accuracy of aqueous exposure appear to be less relevant when applied to moderate to highly hydrophobic compounds, because this route contributes only marginally to total uptake. The determination of chemical bioavailability and the increase in understanding and qualifying...

  17. [Cancer treatment in Skane and in Sjaelland. Do differences concerning examination and treatment explain reduced survival among Danish cancer patients?

    DEFF Research Database (Denmark)

    Specht, Lena; Landberg, T.

    2001-01-01

    INTRODUCTION: Danish cancer patients generally have a poorer survival than Swedish cancer patients. The difference is most pronounced for certain tumour types, e.g. common types such as lung, breast, colorectal, and prostate cancer. The reasons are not clear. The present article examines...... if differences in the diagnostic workup and treatment can explain some of this variation. MATERIAL AND METHODS: Aspects of the diagnostic workup and treatment of the above mentioned four cancer types are examined using data from cancer registry analyses and official reports. These data are seen in the context...... of counts of trained personnel and equipment in cancer diagnostics and treatment in the two countries. RESULTS: With regard to lung and breast cancer, the data seem to indicate that Danish patients are diagnosed later, and that Denmark lags behind in treatment capacity. With regard to rectal cancer...

  18. Heterogeneity of long-history migration explains cultural differences in reports of emotional expressivity and the functions of smiles.

    Science.gov (United States)

    Rychlowska, Magdalena; Miyamoto, Yuri; Matsumoto, David; Hess, Ursula; Gilboa-Schechtman, Eva; Kamble, Shanmukh; Muluk, Hamdi; Masuda, Takahiko; Niedenthal, Paula Marie

    2015-05-12

    A small number of facial expressions may be universal in that they are produced by the same basic affective states and recognized as such throughout the world. However, other aspects of emotionally expressive behavior vary widely across culture. Just why do they vary? We propose that some cultural differences in expressive behavior are determined by historical heterogeneity, or the extent to which a country's present-day population descended from migration from numerous vs. few source countries over a period of 500 y. Our reanalysis of data on cultural rules for displaying emotion from 32 countries [n = 5,340; Matsumoto D, Yoo S, Fontaine J (2008) J Cross Cult Psychol 39(1):55-74] reveals that historical heterogeneity explains substantial, unique variance in the degree to which individuals believe that emotions should be openly expressed. We also report an original study of the underlying states that people believe are signified by a smile. Cluster analysis applied to data from nine countries (n = 726), including Canada, France, Germany, India, Indonesia, Israel, Japan, New Zealand, and the United States, reveals that countries group into "cultures of smiling" determined by historical heterogeneity. Factor analysis shows that smiles sort into three social-functional subtypes: pleasure, affiliative, and dominance. The relative importance of these smile subtypes varies as a function of historical heterogeneity. These findings thus highlight the power of social-historical factors to explain cross-cultural variation in emotional expression and smile behavior.

  19. The Differential role of parenting, peers, and temperament for explaining interindividual differences in 18-months-olds' comforting and helping.

    Science.gov (United States)

    Schuhmacher, Nils; Collard, Jenny; Kärtner, Joscha

    2017-02-01

    This study analyzes temperamental and social correlates of 18-month-olds' (N=58) instrumental helping (i.e., handing over out-of-reach objects) and comforting (i.e., alleviating experimenter's distress). While out-of-reach helping as a basic type of prosocial behavior was not associated with any of the social and temperamental variables, comforting was associated with maternal responsible parenting, day care attendance, and temperamental fear, accounting for 34% of the total variance in a corresponding regression model. The data of the present study suggest that, while simple instrumental helping seems to be a robust developmental phenomenon, comforting is associated with specific social experiences and child temperament that constitute interindividual differences and thereby help to explain the domain-specific development of prosociality. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Cognitive aging explains age-related differences in face-based recognition of basic emotions except for anger and disgust.

    Science.gov (United States)

    Suzuki, Atsunobu; Akiyama, Hiroko

    2013-01-01

    This study aimed at a detailed understanding of the possible dissociable influences of cognitive aging on the recognition of facial expressions of basic emotions (happiness, surprise, fear, anger, disgust, and sadness). The participants were 36 older and 36 young adults. They viewed 96 pictures of facial expressions and were asked to choose one emotion that best described each. Four cognitive tasks measuring the speed of processing and fluid intelligence were also administered, the scores of which were used to compute a composite measure of general cognitive ability. A series of hierarchical regression analyses revealed that age-related deficits in identifying happiness, surprise, fear, and sadness were statistically explained by general cognitive ability, while the differences in anger and disgust were not. This provides clear evidence that age-related cognitive impairment remarkably and differentially affects the recognition of basic emotions, contrary to the common view that cognitive aging has a uniformly minor effect.

  1. What Explains Differences in Availability of Community Health-Related Services for Seniors in the United States?

    Science.gov (United States)

    Warner, Mildred E; Xu, Yuanshuo; Morken, Lydia J

    2016-06-01

    This study analyzes the links between planning, the built environment, and availability of health-related community services across U.S. urban and rural communities. We analyze the first national survey of health-related community services for seniors (2010 Maturing of America), covering 1,459 U.S. cities and counties. We tested the influence of morbidity (diabetes and obesity), city management, socioeconomic characteristics, planning and the built environment, metro status, and government finance. Community health-related services are more common in places that plan for and involve seniors in planning processes. Places with higher need and government capacity also show higher levels. Service levels in rural communities are not lower after controlling for other population characteristics. Morbidity measures (diabetes and obesity) do not explain differences in service availability. Policies promoting planning for aging and elder involvement in the planning process have the greatest impact on the level of community health-related services for seniors.

  2. Do Physical and Relational Aggression Explain Adolescents' Friendship Selection? The Competing Roles of Network Characteristics, Gender, and Social Status

    NARCIS (Netherlands)

    Dijkstra, Jan Kornelis; Berger, Christian; Lindenberg, Siegwart

    2011-01-01

    The role of physical and relational aggression in adolescents' friendship selection was examined in a longitudinal sample of 274 Chilean students from 5th and 6th grade followed over 1 year. Longitudinal social network modeling (SIENA) was used to study selection processes for aggression while

  3. Can Parenting Practices Explain the Differences in Beverage Intake According to Socio-Economic Status: The Toybox-Study

    Directory of Open Access Journals (Sweden)

    An-Sofie Pinket

    2016-09-01

    Full Text Available Previous research indicated that preschoolers of lower socioeconomic status (SES consume less healthy beverages than high SES preschoolers. The purpose of this study is to investigate the mediating role of parenting practices in the relationship between SES and plain water, soft drink and prepacked fruit juice (FJ consumption in European preschoolers. Parents/caregivers of 3.5 to 5.5 years old (n = 6776 recruited through kindergartens in six European countries within the ToyBox-study completed questionnaires on socio-demographics, parenting practices and a food frequency questionnaire. Availability of sugared beverages and plain water, permissiveness towards sugared beverages and lack of self-efficacy showed a mediating effect on SES-differences in all three beverages. Rewarding with sugared beverages significantly mediated SES-differences for both plain water and prepacked FJ. Encouragement to drink plain water and awareness significantly mediated SES-differences for, respectively, plain water and prepacked FJ consumption. Avoiding negative modelling did not mediate any associations. Overall, lower SES preschoolers were more likely to be confronted with lower levels of favourable and higher levels of unfavourable parenting practices, which may lead to higher sugared beverage and lower plain water consumption. The current study highlights the importance of parenting practices in explaining the relation between SES and both healthy and unhealthy beverage consumption.

  4. What explains the different rates of human papillomavirus vaccination among adolescent males and females in the United States?

    Directory of Open Access Journals (Sweden)

    Yoonyoung Choi

    2016-12-01

    Full Text Available Purpose: To identify factors that explain differences in HPV vaccination rates for male and female adolescents and to determine self-reported barriers by parents affecting vaccination decisions. Methods: The sample included adolescents 13–17 years old with a vaccination record documented in the 2012 and 2013 National Immunization Survey-Teen dataset. A logistic regression model was developed with 13 socio-demographic factors and survey year, along with significant interaction pairs with gender. Results: Subjects included 20,355 and 18,350 adolescent boys and girls, respectively. About half of the females (56% received at least one dose of HPV vaccine, compared to 28% of males. Several factors differed between males and females, including higher vaccination rates among non-Hispanic Black males and lower vaccination rates for non-Hispanic Black females compared to Whites; and a stronger association with health care provider recommendation among males. The most common parental reasons for not vaccinating their children included ‘not recommended by a health care provider’ for males (24%, and ‘unnecessary’ for females (18%. Conclusion: We found a significant gender interaction with several socio-demographic variables in predicting vaccination uptake. These gender differences may be partially an artifact of timing, because male vaccination became routine approximately five years after female vaccination. Keywords: Human papillomavirus, Adolescent health, Vaccination, NIS-Teen, Gender interaction

  5. Can Parenting Practices Explain the Differences in Beverage Intake According to Socio-Economic Status: The Toybox-Study.

    Science.gov (United States)

    Pinket, An-Sofie; De Craemer, Marieke; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Cardon, Greet; Androutsos, Odysseas; Koletzko, Berthold; Moreno, Luis A; Socha, Piotr; Iotova, Violeta; Manios, Yannis; Van Lippevelde, Wendy

    2016-09-23

    Previous research indicated that preschoolers of lower socioeconomic status (SES) consume less healthy beverages than high SES preschoolers. The purpose of this study is to investigate the mediating role of parenting practices in the relationship between SES and plain water, soft drink and prepacked fruit juice (FJ) consumption in European preschoolers. Parents/caregivers of 3.5 to 5.5 years old (n = 6776) recruited through kindergartens in six European countries within the ToyBox-study completed questionnaires on socio-demographics, parenting practices and a food frequency questionnaire. Availability of sugared beverages and plain water, permissiveness towards sugared beverages and lack of self-efficacy showed a mediating effect on SES-differences in all three beverages. Rewarding with sugared beverages significantly mediated SES-differences for both plain water and prepacked FJ. Encouragement to drink plain water and awareness significantly mediated SES-differences for, respectively, plain water and prepacked FJ consumption. Avoiding negative modelling did not mediate any associations. Overall, lower SES preschoolers were more likely to be confronted with lower levels of favourable and higher levels of unfavourable parenting practices, which may lead to higher sugared beverage and lower plain water consumption. The current study highlights the importance of parenting practices in explaining the relation between SES and both healthy and unhealthy beverage consumption.

  6. Cultural diversity and saccade similarities: culture does not explain saccade latency differences between Chinese and Caucasian participants.

    Science.gov (United States)

    Knox, Paul C; Wolohan, Felicity D A

    2014-01-01

    A central claim of cultural neuroscience is that the culture to which an individual belongs plays a key role in shaping basic cognitive processes and behaviours, including eye movement behaviour. We previously reported a robust difference in saccade behaviour between Chinese and Caucasian participants; Chinese participants are much more likely to execute low latency express saccades, in circumstances in which these are normally discouraged. To assess the extent to which this is the product of culture we compared a group of 70 Chinese overseas students (whose primary cultural exposure was that of mainland China), a group of 45 participants whose parents were Chinese but who themselves were brought up in the UK (whose primary cultural exposure was western European) and a group of 70 Caucasian participants. Results from the Schwartz Value Survey confirmed that the UK-Chinese group were culturally similar to the Caucasian group. However, their patterns of saccade latency were identical to the mainland Chinese group, and different to the Caucasian group. We conclude that at least for the relatively simple reflexive saccade behaviour we have investigated, culture cannot explain the observed differences in behaviour.

  7. Risk behaviors and sports facilities do not explain socioeconomic differences in childhood obesity: a cross-sectional study

    National Research Council Canada - National Science Library

    Albaladejo, Romana; Villanueva, Rosa; Navalpotro, Lourdes; Ortega, Paloma; Astasio, Paloma; Regidor, Enrique

    2014-01-01

    To assess whether the relationship between neighborhood socioeconomic context of residence and childhood obesity is explained by family socioeconomic position, risk behaviors and availability of sports facilities...

  8. How Different Medical School Selection Processes Call upon Different Personality Characteristics

    NARCIS (Netherlands)

    Schripsema, Nienke R; van Trigt, Anke M; van der Wal, Martha A; Cohen-Schotanus, Janke

    2016-01-01

    BACKGROUND: Research indicates that certain personality traits relate to performance in the medical profession. Yet, personality testing during selection seems ineffective. In this study, we examine the extent to which different medical school selection processes call upon desirable personality

  9. Does education explain ethnic differences in myopia prevalence? A population-based study of young adult males in Singapore.

    Science.gov (United States)

    Wu, H M; Seet, B; Yap, E P; Saw, S M; Lim, T H; Chia, K S

    2001-04-01

    To study interethnic variation in myopia prevalence and severity in young adult males in Singapore and to determine whether these variations are related to differences in education level. A population-based survey of refractive errors in a cohort of 15,095 military conscripts between July 1996 and June 1997 using noncycloplegic autorefraction and a standard questionnaire. Prevalence rates of myopia (education level. Singapore has one of the highest prevalences of myopia (79.3%) and severe myopia (13.1%), with Chinese having higher rates (82.2%, 95% confidence interval 81.5, 82.9) compared with Indians (68.7%, 95% confidence interval 65.1, 67.1) and Malays (65.0%, 95% confidence interval 62.9, 67.1). Education was strongly associated with prevalence and severity of myopia. However, significant interethnic variation persisted after adjusting for education. There is a high prevalence of myopia in Singapore. Although prevalence and severity of myopia were strongly associated with education, interethnic variation observed was not fully explained by differences in education level.

  10. Estimated cochlear delays in low best-frequency neurons in the barn owl cannot explain coding of interaural time difference.

    Science.gov (United States)

    Singheiser, Martin; Fischer, Brian J; Wagner, Hermann

    2010-10-01

    The functional role of the low-frequency range (barn owl hearing is not well understood. Here, it was tested whether cochlear delays could explain the representation of interaural time difference (ITD) in this frequency range. Recordings were obtained from neurons in the core of the central nucleus of the inferior colliculus. The response of these neurons varied with the ITD of the stimulus. The response peak shared by all neurons in a dorsoventral penetration was called the array-specific ITD and served as criterion for the representation of a given ITD in a neuron. Array-specific ITDs were widely distributed. Isolevel frequency response functions obtained with binaural, contralateral, and ispilateral stimulation exhibited a clear response peak and the accompanying frequency was called the best frequency. The data were tested with respect to predictions of a model, the stereausis model, assuming cochlear delays as source for the best ITD of a neuron. According to this model, different cochlear delays determined by mismatches between the ipsilateral and contralateral best frequencies are the source for the ITD in a binaural neuron. The mismatch should depend on the best frequency and the best ITD. The predictions of the stereausis model were not fulfilled in the low best-frequency neurons analyzed here. It is concluded that cochlear delays are not responsible for the representation of best ITD in the barn owl.

  11. Explaining Differences in Subjective Well-Being Across 33 Nations Using Multilevel Models: Universal Personality, Cultural Relativity, and National Income.

    Science.gov (United States)

    Cheng, Cecilia; Cheung, Mike W-L; Montasem, Alex

    2016-02-01

    This multinational study simultaneously tested three prominent hypotheses--universal disposition, cultural relativity, and livability--that explained differences in subjective well-being across nations. We performed multilevel structural equation modeling to examine the hypothesized relationships at both individual and cultural levels in 33 nations. Participants were 6,753 university students (2,215 men; 4,403 women; 135 did not specify), and the average age of the entire sample was 20.97 years (SD = 2.39). Both individual- and cultural-level analyses supported the universal disposition and cultural relativity hypotheses by revealing significant associations of subjective well-being with Extraversion, Neuroticism, and independent self-construal. In addition, interdependent self-construal was positively related to life satisfaction at the individual level only, whereas aggregated negative affect was positively linked with aggregate levels of Extraversion and interdependent self-construal at the cultural level only. Consistent with the livability hypothesis, gross national income (GNI) was related to aggregate levels of negative affect and life satisfaction. There was also a quadratic relationship between GNI and aggregated positive affect. Our findings reveal that universal disposition, cultural self-construal, and national income can elucidate differences in subjective well-being, but the multilevel analyses advance the literature by yielding new findings that cannot be identified in studies using individual-level analyses alone. © 2014 Wiley Periodicals, Inc.

  12. Does selective migration explain the Hispanic paradox? A comparative analysis of Mexicans in the U.S. and Mexico.

    Science.gov (United States)

    Bostean, Georgiana

    2013-06-01

    Latino immigrants, particularly Mexican, have some health advantages over U.S.-born Mexicans and Whites. Because of their lower socioeconomic status, this phenomenon has been called the epidemiologic "Hispanic Paradox." While cultural theories have dominated explanations for the Paradox, the role of selective migration has been inadequately addressed. This study is among the few to combine Mexican and U.S. data to examine health selectivity in activity limitation, self-rated health, and chronic conditions among Mexican immigrants, ages 18 and over. Drawing on theories of selective migration, this study tested the "healthy migrant" and "salmon-bias" hypotheses by comparing the health of Mexican immigrants in the U.S. to non-migrants in Mexico, and to return migrants in Mexico. Results suggest that there are both healthy migrant and salmon-bias effects in activity limitation, but not other health aspects. In fact, consistent with prior research, immigrants are negatively selected on self-rated health. Future research should consider the complexities of migrants' health profiles and examine selection mechanisms alongside other factors such as acculturation.

  13. Can differences in phosphorus uptake kinetics explain the distribution of cattail and sawgrass in the Florida Everglades?

    Science.gov (United States)

    Brix, Hans; Lorenzen, Bent; Mendelssohn, Irving A; McKee, Karen L; Miao, Shili

    2010-02-08

    Cattail (Typha domingensis) has been spreading in phosphorus (P) enriched areas of the oligotrophic Florida Everglades at the expense of sawgrass (Cladium mariscus spp. jamaicense). Abundant evidence in the literature explains how the opportunistic features of Typha might lead to a complete dominance in P-enriched areas. Less clear is how Typha can grow and acquire P at extremely low P levels, which prevail in the unimpacted areas of the Everglades. Apparent P uptake kinetics were measured for intact plants of Cladium and Typha acclimated to low and high P at two levels of oxygen in hydroponic culture. The saturated rate of P uptake was higher in Typha than in Cladium and higher in low-P acclimated plants than in high-P acclimated plants. The affinity for P uptake was two-fold higher in Typha than in Cladium, and two- to three-fold higher for low-P acclimated plants compared to high-P acclimated plants. As Cladium had a greater proportion of its biomass allocated to roots, the overall uptake capacity of the two species at high P did not differ. At low P availability, Typha increased biomass allocation to roots more than Cladium. Both species also adjusted their P uptake kinetics, but Typha more so than Cladium. The adjustment of the P uptake system and increased biomass allocation to roots resulted in a five-fold higher uptake per plant for Cladium and a ten-fold higher uptake for Typha. Both Cladium and Typha adjust P uptake kinetics in relation to plant demand when P availability is high. When P concentrations are low, however, Typha adjusts P uptake kinetics and also increases allocation to roots more so than Cladium, thereby improving both efficiency and capacity of P uptake. Cladium has less need to adjust P uptake kinetics because it is already efficient at acquiring P from peat soils (e.g., through secretion of phosphatases, symbiosis with arbuscular mycorrhizal fungi, nutrient conservation growth traits). Thus, although Cladium and Typha have qualitatively

  14. Can differences in phosphorus uptake kinetics explain the distribution of cattail and sawgrass in the Florida Everglades?

    Directory of Open Access Journals (Sweden)

    McKee Karen L

    2010-02-01

    Full Text Available Abstract Background Cattail (Typha domingensis has been spreading in phosphorus (P enriched areas of the oligotrophic Florida Everglades at the expense of sawgrass (Cladium mariscus spp. jamaicense. Abundant evidence in the literature explains how the opportunistic features of Typha might lead to a complete dominance in P-enriched areas. Less clear is how Typha can grow and acquire P at extremely low P levels, which prevail in the unimpacted areas of the Everglades. Results Apparent P uptake kinetics were measured for intact plants of Cladium and Typha acclimated to low and high P at two levels of oxygen in hydroponic culture. The saturated rate of P uptake was higher in Typha than in Cladium and higher in low-P acclimated plants than in high-P acclimated plants. The affinity for P uptake was two-fold higher in Typha than in Cladium, and two- to three-fold higher for low-P acclimated plants compared to high-P acclimated plants. As Cladium had a greater proportion of its biomass allocated to roots, the overall uptake capacity of the two species at high P did not differ. At low P availability, Typha increased biomass allocation to roots more than Cladium. Both species also adjusted their P uptake kinetics, but Typha more so than Cladium. The adjustment of the P uptake system and increased biomass allocation to roots resulted in a five-fold higher uptake per plant for Cladium and a ten-fold higher uptake for Typha. Conclusions Both Cladium and Typha adjust P uptake kinetics in relation to plant demand when P availability is high. When P concentrations are low, however, Typha adjusts P uptake kinetics and also increases allocation to roots more so than Cladium, thereby improving both efficiency and capacity of P uptake. Cladium has less need to adjust P uptake kinetics because it is already efficient at acquiring P from peat soils (e.g., through secretion of phosphatases, symbiosis with arbuscular mycorrhizal fungi, nutrient conservation growth

  15. Why kin and group selection models may not be enough to explain human other-regarding behaviour

    NARCIS (Netherlands)

    van Veelen, C.M.

    2006-01-01

    Models of kin or group selection usually feature only one possible fitness transfer. The phenotypes are either to make this transfer or not to make it and for any given fitness transfer, Hamilton's rule predicts which of the two phenotypes will spread. In this article we allow for the possibility

  16. Comment on Gohli et al. (2013): "Does promiscuity explain differences in levels of genetic diversity across passerine birds?".

    Science.gov (United States)

    Spurgin, Lewis G

    2013-10-01

    Gohli et al. (2013) report a positive relationship between genetic diversity and promiscuity across passerine birds, and suggest that female promiscuity acts as a form of balancing selection, maintaining differences in genetic variation across species. This is an interesting hypothesis, but the enormous variation in genetic diversity present within species is not taken into account in their analyses. This, combined with a small sample size at several levels, makes the relationship between genetic diversity and promiscuity very difficult to interpret. Demonstrating that species-level differences in genetic diversity (if they occur at all) are affected by promiscuity would require a far more comprehensive study than is presently possible. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  17. Differences in U root-to-shoot translocation between plant species explained by U distribution in roots

    Energy Technology Data Exchange (ETDEWEB)

    Straczek, Anne; Duquene, Lise [Belgium Nuclear Research Centre (SCK.CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Wegrzynek, Dariusz [IAEA, Seibersdorf Laboratories, A-2444 Seibersdorf (Austria); Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow (Poland); Chinea-Cano, Ernesto [IAEA, Seibersdorf Laboratories, A-2444 Seibersdorf (Austria); Wannijn, Jean [Belgium Nuclear Research Centre (SCK.CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Navez, Jacques [Royal Museum of Africa, Department of Geology, Leuvensesteenweg 13, 3080 Tervuren (Belgium); Vandenhove, Hildegarde, E-mail: hvandenh@sckcen.b [Belgium Nuclear Research Centre (SCK.CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium)

    2010-03-15

    Accumulation and distribution of uranium in roots and shoots of four plants species differing in their cation exchange capacity of roots (CECR) was investigated. After exposure in hydroponics for seven days to 100 mumol U L{sup -1}, distribution of uranium in roots was investigated through chemical extraction of roots. Higher U concentrations were measured in roots of dicots which showed a higher CECR than monocot species. Chemical extractions indicated that uranium is mostly located in the apoplasm of roots of monocots but that it is predominantly located in the symplasm of roots of dicots. Translocation of U to shoot was not significantly affected by the CECR or distribution of U between symplasm and apoplasm. Distribution of uranium in roots was investigated through chemical extraction of roots for all species. Additionally, longitudinal and radial distribution of U in roots of maize and Indian mustard, respectively showing the lowest and the highest translocation, was studied following X-ray fluorescence (XRF) analysis of specific root sections. Chemical analysis and XRF analysis of roots of maize and Indian mustard clearly indicated a higher longitudinal and radial transport of uranium in roots of Indian mustard than in roots of maize, where uranium mostly accumulated in root tips. These results showed that even if CECR could partly explain U accumulation in roots, other mechanisms like radial and longitudinal transport are implied in the translocation of U to the shoot.

  18. Mountain uplift explains differences in Palaeogene patterns of mammalian evolution and extinction between North America and Europe.

    Science.gov (United States)

    Eronen, Jussi T; Janis, Christine M; Chamberlain, C Page; Mulch, Andreas

    2015-06-22

    Patterns of late Palaeogene mammalian evolution appear to be very different between Eurasia and North America. Around the Eocene-Oligocene (EO) transition global temperatures in the Northern Hemisphere plummet: following this, European mammal faunas undergo a profound extinction event (the Grande Coupure), while in North America they appear to pass through this temperature event unscathed. Here, we investigate the role of surface uplift to environmental change and mammalian evolution through the Palaeogene (66-23 Ma). Palaeogene regional surface uplift in North America caused large-scale reorganization of precipitation patterns, particularly in the continental interior, in accord with our combined stable isotope and ecometric data. Changes in mammalian faunas reflect that these were dry and high-elevation palaeoenvironments. The scenario of Middle to Late Eocene (50-37 Ma) surface uplift, together with decreasing precipitation in higher-altitude regions of western North America, explains the enigma of the apparent lack of the large-scale mammal faunal change around the EO transition that characterized western Europe. We suggest that North American mammalian faunas were already pre-adapted to cooler and drier conditions preceding the EO boundary, resulting from the effects of a protracted history of surface uplift. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  19. Different mechanisms must be considered to explain the increase in hippocampal neural precursor cell proliferation by physical activity

    Directory of Open Access Journals (Sweden)

    Rupert W Overall

    2016-08-01

    Full Text Available The number of proliferating neural precursor cells in the adult hippocampus is strongly increased by physical activity. The mechanisms through which this behavioral stimulus induces cell proliferation, however, are not yet understood. In fact, even the mode of proliferation of the stem and progenitor cells is not exactly known. Evidence exists for several mechanisms including cell cycle shortening, reduced cell death and stem cell recruitment, but as yet no model can account for all observations. An appreciation of how the cells proliferate, however, is crucial to our ability to model the neurogenic process and predict its behavior in response to pro-neurogenic stimuli. In a recent study, we addressed modulation of the cell cycle length as one possible mode of regulation of precursor cell proliferation in running mice. Our results indicated that the observed increase in number of proliferating cells could not be explained through a shortening of the cell cycle. We must therefore consider other mechanisms by which physical activity leads to enhanced precursor cell proliferation. Here we review the evidence for and against several different hypotheses and discuss the implications for future research in the field.

  20. Food selectivity and diet switch can explain the slow feeding of herbivorous coral-reef fishes during the morning.

    Science.gov (United States)

    Khait, Ruth; Obolski, Uri; Hadany, Lilach; Genin, Amatzia

    2013-01-01

    Most herbivorous coral-reef fishes feed slower in the morning than in the afternoon. Given the typical scarcity of algae in coral reefs, this behavior seems maladaptive. Here we suggest that the fishes' slow feeding during the morning is an outcome of highly selective feeding on scarcely found green algae. The rarity of the food requires longer search time and extended swimming tracks, resulting in lower bite rates. According to our findings by noon the fish seem to stop their search and switch to indiscriminative consumption of benthic algae, resulting in apparent higher feeding rates. The abundance of the rare preferable algae gradually declines from morning to noon and seems to reach its lowest levels around the switch time. Using in situ experiments we found that the feeding pattern is flexible, with the fish exhibiting fast feeding rates when presented with ample supply of preferable algae, regardless of the time of day. Analyses of the fish's esophagus content corroborated our conclusion that their feeding was highly selective in the morning and non-selective in the afternoon. Modeling of the fishes' behavior predicted that the fish should perform a diel diet shift when the preferred food is relatively rare, a situation common in most coral reefs found in a warm, oligotrophic ocean.

  1. Food selectivity and diet switch can explain the slow feeding of herbivorous coral-reef fishes during the morning.

    Directory of Open Access Journals (Sweden)

    Ruth Khait

    Full Text Available Most herbivorous coral-reef fishes feed slower in the morning than in the afternoon. Given the typical scarcity of algae in coral reefs, this behavior seems maladaptive. Here we suggest that the fishes' slow feeding during the morning is an outcome of highly selective feeding on scarcely found green algae. The rarity of the food requires longer search time and extended swimming tracks, resulting in lower bite rates. According to our findings by noon the fish seem to stop their search and switch to indiscriminative consumption of benthic algae, resulting in apparent higher feeding rates. The abundance of the rare preferable algae gradually declines from morning to noon and seems to reach its lowest levels around the switch time. Using in situ experiments we found that the feeding pattern is flexible, with the fish exhibiting fast feeding rates when presented with ample supply of preferable algae, regardless of the time of day. Analyses of the fish's esophagus content corroborated our conclusion that their feeding was highly selective in the morning and non-selective in the afternoon. Modeling of the fishes' behavior predicted that the fish should perform a diel diet shift when the preferred food is relatively rare, a situation common in most coral reefs found in a warm, oligotrophic ocean.

  2. Do Differences in Risk Factors Explain the Lower Rates of Coronary Heart Disease in Japanese Versus U.S. Women?

    Science.gov (United States)

    Willcox, Bradley J.; Usui, Takeshi; Carr, John Jeffrey; Barinas-Mitchell, Emma J.M.; Masaki, Kamal H.; Watanabe, Makoto; Tracy, Russell P.; Bertolet, Marianne H.; Evans, Rhobert W.; Nishimura, Kunihiko; Sutton-Tyrrell, Kim; Kuller, Lewis H.; Miyamoto, Yoshihiro

    2013-01-01

    Abstract Background Mortality from coronary heart disease (CHD) in women in Japan is one of the lowest in developed countries. In an attempt to shed some light on possible reasons of lower CHD in women in Japan compared with the United States, we extensively reviewed and analyzed existing national data and recent literature. Methods We searched recent epidemiological studies that reported incidence of acute myocardial infarction (AMI) and examined risk factors for CHD in women in Japan. Then, we compared trends in risk factors between women currently aged 50–69 years in Japan and the United States, using national statistics and other available resources. Results Recent epidemiological studies have clearly shown that AMI incidence in women in Japan is lower than that reported from other countries, and that lipids, blood pressure (BP), diabetes, smoking, and early menopause are independent risk factors. Comparing trends in risk factors between women in Japan and the United States, current levels of serum total cholesterol are higher in women in Japan and levels have been similar at least since 1990. Levels of BP have been higher in in Japan for the past 3 decades. Prevalence of type 2 diabetes has been similar in Japanese and white women currently aged 60–69 for the past 2 decades. In contrast, rates of cigarette smoking, although low in women in both countries, have been lower in women in Japan. Conclusions Differences in risk factors and their trends are unlikely to explain the difference in CHD rates in women in Japan and the United States. Determining the currently unknown factors responsible for low CHD mortality in women in Japan may lead to new strategy for CHD prevention. PMID:24073782

  3. Urban-Rural Differences Explain the Association between Serum 25-Hydroxyvitamin D Level and Insulin Resistance in Korea

    Directory of Open Access Journals (Sweden)

    Bo Mi Song

    2014-12-01

    Full Text Available An increasing number of studies report associations between low serum 25-hydroxyvitamin D [25(OHD] level and insulin resistance; however, whether low vitamin D levels directly contribute to increased insulin resistance is unclear. We investigated the impact of residential area on the association between 25(OHD and insulin resistance in elderly Koreans. Using data from the Korean Urban Rural Elderly study, we conducted cross-sectional analyses in 1628 participants (505 men and 1123 women. Serum 25(OHD was analyzed as both continuous and categorized variables. Homeostasis model assessment for insulin resistance (HOMA-IR was calculated using fasting blood glucose and insulin levels. In men, 25(OHD level was inversely associated with HOMA-IR (standardized β = −0.133, p < 0.001 after adjustment for age, body mass index, waist circumference, smoking, alcohol intake, exercise, and study year. However, we noted significant urban-rural differences in 25(OHD level (43.4 versus 65.6 nmol/L; p < 0.001 and HOMA-IR (1.2 versus 0.8 mmol·pmol/L2; p < 0.001. When we additionally adjusted for residential area, the association between 25(OHD and HOMA-IR was attenuated (standardized β = −0.063, p = 0.115. In women, the association between 25(OHD and HOMA-IR was not significant before or after adjustment for residential area. Environmental or lifestyle differences in urban and rural areas may largely explain the inverse association between serum 25(OHD and insulin resistance.

  4. Lymphopenia-induced proliferation in aire-deficient mice helps to explain their autoimmunity and differences from human patients.

    Science.gov (United States)

    Kisand, Kai; Peterson, Pärt; Laan, Martti

    2014-01-01

    Studies on autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED) and its mouse model - both caused by mutant AIRE - have greatly advanced the understanding of thymic processes that generate a self-tolerant T-cell repertoire. Much is now known about the molecular mechanisms by which AIRE induces tissue-specific antigen expression in thymic epithelium, and how this leads to negative selection of auto-reactive thymocytes. However, we still do not understand the processes that lead to the activation of any infrequent naïve auto-reactive T-cells exported by AIRE-deficient thymi. Also, the striking phenotypic differences between APECED and its mouse models have puzzled researchers for years. The aim of this review is to suggest explanations for some of these unanswered questions, based on a fresh view of published experiments. We review evidence that auto-reactive T-cells can be activated by the prolonged neonatal lymphopenia that naturally develops in young Aire-deficient mice due to delayed export of mature thymocytes. Lymphopenia-induced proliferation (LIP) helps to fill the empty space; by favoring auto-reactive T-cells, it also leads to lymphocyte infiltration in the same tissues as in day 3 thymectomized animals. The LIP becomes uncontrolled when loss of Aire is combined with defects in genes responsible for anergy induction and Treg responsiveness, or in signaling from the T-cell receptor and homeostatic cytokines. In APECED patients, LIP is much less likely to be involved in activation of naïve auto-reactive T-cells, as humans are born with a more mature immune system than in neonatal mice. We suggest that human AIRE-deficiency presents with different phenotypes because of additional precipitating factors that compound the defective negative selection of potentially autoaggressive tissue-specific thymocytes.

  5. Explaining differences between bioaccumulation measurements in laboratory and field data through use of a probabilistic modeling approach

    Science.gov (United States)

    Selck, Henriette; Drouillard, Ken; Eisenreich, Karen; Koelmans, Albert A.; Palmqvist, Annemette; Ruus, Anders; Salvito, Daniel; Schultz, Irv; Stewart, Robin; Weisbrod, Annie; van den Brink, Nico W.; van den Heuvel-Greve, Martine

    2012-01-01

    In the regulatory context, bioaccumulation assessment is often hampered by substantial data uncertainty as well as by the poorly understood differences often observed between results from laboratory and field bioaccumulation studies. Bioaccumulation is a complex, multifaceted process, which calls for accurate error analysis. Yet, attempts to quantify and compare propagation of error in bioaccumulation metrics across species and chemicals are rare. Here, we quantitatively assessed the combined influence of physicochemical, physiological, ecological, and environmental parameters known to affect bioaccumulation for 4 species and 2 chemicals, to assess whether uncertainty in these factors can explain the observed differences among laboratory and field studies. The organisms evaluated in simulations including mayfly larvae, deposit-feeding polychaetes, yellow perch, and little owl represented a range of ecological conditions and biotransformation capacity. The chemicals, pyrene and the polychlorinated biphenyl congener PCB-153, represented medium and highly hydrophobic chemicals with different susceptibilities to biotransformation. An existing state of the art probabilistic bioaccumulation model was improved by accounting for bioavailability and absorption efficiency limitations, due to the presence of black carbon in sediment, and was used for probabilistic modeling of variability and propagation of error. Results showed that at lower trophic levels (mayfly and polychaete), variability in bioaccumulation was mainly driven by sediment exposure, sediment composition and chemical partitioning to sediment components, which was in turn dominated by the influence of black carbon. At higher trophic levels (yellow perch and the little owl), food web structure (i.e., diet composition and abundance) and chemical concentration in the diet became more important particularly for the most persistent compound, PCB-153. These results suggest that variation in bioaccumulation

  6. Complexity explained

    CERN Document Server

    Erdi, Peter

    2008-01-01

    This book explains why complex systems research is important in understanding the structure, function and dynamics of complex natural and social phenomena. Readers will learn the basic concepts and methods of complex system research.

  7. Psychometric Personality Differences Between Candidates in Astronaut Selection.

    Science.gov (United States)

    Mittelstädt, Justin M; Pecena, Yvonne; Oubaid, Viktor; Maschke, Peter

    This paper investigates personality traits as potential factors for success in an astronaut selection by comparing personality profiles of unsuccessful and successful astronaut candidates in different phases of the ESA selection procedure. It is further addressed whether personality traits could predict an overall assessment rating at the end of the selection. In 2008/2009, ESA performed an astronaut selection with 902 candidates who were either psychologically recommended for mission training (N = 46) or failed in basic aptitude (N = 710) or Assessment Center and interview testing (N = 146). Candidates completed the Temperament Structure Scales (TSS) and the NEO Personality Inventory Revised (NEO-PI-R). Those candidates who failed in basic aptitude testing showed higher levels of Neuroticism (M = 49.8) than the candidates who passed that phase (M = 45.4 and M = 41.6). Additionally, candidates who failed in basic testing had lower levels of Agreeableness (M = 132.9) than recommended candidates (M = 138.1). TSS scales for Achievement (r = 0.19) and Vitality (r = 0.18) showed a significant correlation with the overall assessment rating given by a panel board after a final interview. Results indicate that a personality profile similar to Helmreich's "Right Stuff" is beneficial in astronaut selection. Influences of test anxiety on performance are discussed. Mittelstädt JM, Pecena Y, Oubaid V, Maschke P. Psychometric personality differences between candidates in astronaut selection. Aerosp Med Hum Perform. 2016; 87(11):933-939.

  8. Regional Differences of Undiagnosed Type 2 Diabetes and Prediabetes Prevalence Are Not Explained by Known Risk Factors

    Science.gov (United States)

    Tamayo, Teresa; Schipf, Sabine; Meisinger, Christine; Schunk, Michaela; Maier, Werner; Herder, Christian; Roden, Michael; Nauck, Matthias; Peters, Annette; Völzke, Henry; Rathmann, Wolfgang

    2014-01-01

    Background We have previously found regional differences in the prevalence of known type 2 diabetes between northeastern and southern Germany. We aim to also provide prevalence estimates for prediabetes (isolated impaired fasting glucose (i-IFG), isolated glucose intolerance (i-IGT), combined IFG and IGT) and unknown type 2 diabetes for both regions. Methods Prevalence (95%CI) of prediabetes (i-IFG: fasting glucose 5.6–6.9 mmol/l; i-IGT: 2 h postchallenge gluose 7.8–11.0 mmol/l, oral glucose tolerance test (OGTT), ≥8 h overnight fasting) and unknown diabetes were analyzed in two regional population-based surveys (age group 35–79 years): SHIP-TREND (Study of Health in Pomerania (northeast), 2008–2012) and KORA F4 (Cooperative Health Research in the region of Augsburg (south), 2006–2008). Both studies used similar methods, questionnaires, and identical protocols for OGTT. Overall, 1,980 participants from SHIP-TREND and 2,617 participants from KORA F4 were included. Results Age-sex-standardized prevalence estimates (95%CI) of prediabetes and unknown diabetes were considerably higher in the northeast (SHIP-TREND: 43.1%; 40.9–45.3% and 7.1%; 5.9–8.2%) than in the south of Germany (KORA F4: 30.1%; 28.4–31.7% and 3.9%; 3.2–4.6%), respectively. In particular, i-IFG (26.4%; 24.5–28.3% vs. 17.2%; 15.7–18.6%) and IFG+IGT (11.2%; 9.8–12.6% vs. 6.6%; 5.7–7.5%) were more frequent in SHIP-TREND than in KORA. In comparison to normal glucose tolerance, the odds of having unknown diabetes (OR, 95%CI: 2.59; 1.84–3.65) or prediabetes (1.98; 1.70–2.31) was higher in the northeast than in the south after adjustment for known risk factors (obesity, lifestyle). Conclusions The regional differences of prediabetes and unknown diabetes are in line with the geographical pattern of known diabetes in Germany. The higher prevalences in the northeast were not explained by traditional risk factors. PMID:25402347

  9. Regional differences of undiagnosed type 2 diabetes and prediabetes prevalence are not explained by known risk factors.

    Directory of Open Access Journals (Sweden)

    Teresa Tamayo

    Full Text Available We have previously found regional differences in the prevalence of known type 2 diabetes between northeastern and southern Germany. We aim to also provide prevalence estimates for prediabetes (isolated impaired fasting glucose (i-IFG, isolated glucose intolerance (i-IGT, combined IFG and IGT and unknown type 2 diabetes for both regions.Prevalence (95%CI of prediabetes (i-IFG: fasting glucose 5.6-6.9 mmol/l; i-IGT: 2 h postchallenge glucose 7.8-11.0 mmol/l, oral glucose tolerance test (OGTT, ≥ 8 h overnight fasting and unknown diabetes were analyzed in two regional population-based surveys (age group 35-79 years: SHIP-TREND (Study of Health in Pomerania (northeast, 2008-2012 and KORA F4 (Cooperative Health Research in the region of Augsburg (south, 2006-2008. Both studies used similar methods, questionnaires, and identical protocols for OGTT. Overall, 1,980 participants from SHIP-TREND and 2,617 participants from KORA F4 were included.Age-sex-standardized prevalence estimates (95%CI of prediabetes and unknown diabetes were considerably higher in the northeast (SHIP-TREND: 43.1%; 40.9-45.3% and 7.1%; 5.9-8.2% than in the south of Germany (KORA F4: 30.1%; 28.4-31.7% and 3.9%; 3.2-4.6%, respectively. In particular, i-IFG (26.4%; 24.5-28.3% vs. 17.2%; 15.7-18.6% and IFG+IGT (11.2%; 9.8-12.6% vs. 6.6%; 5.7-7.5% were more frequent in SHIP-TREND than in KORA. In comparison to normal glucose tolerance, the odds of having unknown diabetes (OR, 95%CI: 2.59; 1.84-3.65 or prediabetes (1.98; 1.70-2.31 was higher in the northeast than in the south after adjustment for known risk factors (obesity, lifestyle.The regional differences of prediabetes and unknown diabetes are in line with the geographical pattern of known diabetes in Germany. The higher prevalences in the northeast were not explained by traditional risk factors.

  10. Density and length in the neighborhood: Explaining cross-linguistic differences in learning to read in English and Dutch

    NARCIS (Netherlands)

    Marinus, E.; Nation, K.; de Jong, P.F.

    2015-01-01

    Two experiments examined underlying cognitive processes that may explain why it is harder to learn to read in English than in more transparent orthographies such as German and Dutch. Participants were English and Dutch readers from Grades 3 and 4. Experiment 1 probed the transition from serial to

  11. Sport participation and the social and physical environment: Explaining differences between urban and rural areas in the Netherlands

    NARCIS (Netherlands)

    Hoekman, R.H.A.; Breedveld, K.; Kraaykamp, G.L.M.

    2017-01-01

    In this study, we investigated the intensity of sport participation in the Netherlands comparing urban and rural areas. Using a socio-ecological theoretical model, we focussed on the extent to which the rural–urban divide in sport participation is explained by micro-level (socio-demographics),

  12. Multiple hypotheses explain variation in extra-pair paternity at different levels in a single bird family.

    Science.gov (United States)

    Brouwer, Lyanne; van de Pol, Martijn; Aranzamendi, Nataly Hidalgo; Bain, Glen; Baldassarre, Daniel T; Brooker, Lesley C; Brooker, Michael G; Colombelli-Négrel, Diane; Enbody, Erik; Gielow, Kurt; Hall, Michelle L; Johnson, Allison E; Karubian, Jordan; Kingma, Sjouke A; Kleindorfer, Sonia; Louter, Marina; Mulder, Raoul A; Peters, Anne; Pruett-Jones, Stephen; Tarvin, Keith A; Thrasher, Derrick J; Varian-Ramos, Claire W; Webster, Michael S; Cockburn, Andrew

    2017-10-25

    Extra-pair paternity (EPP), where offspring are sired by a male other than the social male, varies enormously both within and among species. Trying to explain this variation has proved difficult because the majority of the interspecific variation is phylogenetically based. Ideally, variation in EPP should be investigated in closely related species, but clades with sufficient variation are rare. We present a comprehensive multifactorial test to explain variation in EPP among individuals in 20 populations of nine species over 89 years from a single bird family (Maluridae). Females had higher EPP in the presence of more helpers, more neighbours or if paired incestuously. Furthermore, higher EPP occurred in years with many incestuous pairs, populations with many helpers and species with high male density or in which males provide less care. Altogether, these variables accounted for 48% of the total and 89% of the interspecific and interpopulation variation in EPP. These findings indicate why consistent patterns in EPP have been so challenging to detect and suggest that a single predictor is unlikely to account for the enormous variation in EPP across levels of analysis. Nevertheless, it also shows that existing hypotheses can explain the variation in EPP well and that the density of males in particular is a good predictor to explain variation in EPP among species when a large part of the confounding effect of phylogeny is excluded. © 2017 John Wiley & Sons Ltd.

  13. Multiple hypotheses explain variation in extra-pair paternity at different levels in a single bird family

    NARCIS (Netherlands)

    Brouwer, Lyanne; van de Pol, Martijn; Aranzamendi, Nataly Hidalgo; Bain, Glen; Baldassarre, Daniel T.; Brooker, Lesley C.; Brooker, Michael G.; Colombelli-Négrel, Diane; Enbody, Erik; Gielow, Kurt; Hall, Michelle L.; Johnson, Allison E.; Karubian, Jordan; kingma, Sjouke A.; Kleindorfer, Sonia; Louter, Marina; Mulder, Raoul A.; Peters, Anne; Pruett-Jones, Stephen; Tarvin, Keith A.; Thrasher, Derrick J.; Varian-Ramos, Claire W.; Webster, Michael S.; Cockburn, Andrew

    2017-01-01

    Extra-pair paternity (EPP), where offspring are sired by a male other than the social male, varies enormously both within and among species. Trying to explain this variation has proved difficult because the majority of the interspecific variation is phylogenetically-based. Ideally, variation in EPP

  14. A comparative perspective on intermarriage : explaining differences in marriage choices among national origin groups in the United States

    NARCIS (Netherlands)

    Kalmijn, M.; Tubergen, F.A. van

    2010-01-01

    Little is known about the validity of group-level theories of ethnic intermarriage despite the fact that such theories are often invoked in explaining why certain ethnic groups are “closed,” whereas others are relatively “open.” We develop a comparative perspective by analyzing the marriage choices

  15. Differences in Gender Performance on Competitive Physics Selection Tests

    Science.gov (United States)

    Wilson, Kate; Low, David; Verdon, Matthew; Verdon, Alix

    2016-01-01

    We have investigated gender differences in performance over the past eight years on the Australian Science Olympiad Exam (ASOE) for physics,which is taken by nearly 1000 high school students each year. The ASOE, run by Australian Science Innovations (ASI), is the initial stage of the process of selection of teams to represent Australia at the…

  16. Assessment of different selection criteriafor reproduction rate in ...

    African Journals Online (AJOL)

    Assessment of different selection criteriafor reproduction rate in Dormer and S.A. Mutton Merino sheep. 2. Luteinizing hormone concentrations in the serum of prepubertal lambs. N.M. Kritzinger, H.W. Stindt and J.M. van der Westhuysen. Winter Rainfall Region, Eisenburg. Data of all the lambs born to the Elsenburg Dormer ...

  17. Increased mortality among HIV-positive men on antiretroviral therapy: survival differences between sexes explained by late initiation in Uganda

    Directory of Open Access Journals (Sweden)

    Kanters S

    2013-05-01

    versus 147 cells/mm3, IQR: 68–212, P-value < 0.0001. Men were at an increased risk of death compared to women (hazard ratio: 1.38, 95% CI: 1.03–1.83. Baseline CD4 cell counts accounted for 43% of the increased risk of death in men (95% CI: 22%–113%. Access to care via antenatal services did not explain differences in outcomes.Conclusion: In this cohort there is a marked increase in risk of mortality for men and approximately half of it can be attributed to their later engagement in care. More effort is required to engage men in care in a timely manner.Keywords: HIV, antiretroviral therapy, gender, Uganda, antenatal care, mortality

  18. Explaining the Immigrant Health Advantage: Self-selection and Protection in Health-Related Factors Among Five Major National-Origin Immigrant Groups in the United States.

    Science.gov (United States)

    Riosmena, Fernando; Kuhn, Randall; Jochem, Warren C

    2017-02-01

    Despite being newcomers, immigrants often exhibit better health relative to native-born populations in industrialized societies. We extend prior efforts to identify whether self-selection and/or protection explain this advantage. We examine migrant height and smoking levels just prior to immigration to test for self-selection; and we analyze smoking behavior since immigration, controlling for self-selection, to assess protection. We study individuals aged 20-49 from five major national origins: India, China, the Philippines, Mexico, and the Dominican Republic. To assess self-selection, we compare migrants, interviewed in the National Health and Interview Surveys (NHIS), with nonmigrant peers in sending nations, interviewed in the World Health Surveys. To test for protection, we contrast migrants' changes in smoking since immigration with two counterfactuals: (1) rates that immigrants would have exhibited had they adopted the behavior of U.S.-born non-Hispanic whites in the NHIS (full "assimilation"); and (2) rates that migrants would have had if they had adopted the rates of nonmigrants in sending countries (no-migration scenario). We find statistically significant and substantial self-selection, particularly among men from both higher-skilled (Indians and Filipinos in height, Chinese in smoking) and lower-skilled (Mexican) undocumented pools. We also find significant and substantial protection in smoking among immigrant groups with stronger relative social capital (Mexicans and Dominicans).

  19. Purkinje cell activity during classical conditioning with different conditional stimuli explains central tenet of Rescorla–Wagner model [corrected].

    Science.gov (United States)

    Rasmussen, Anders; Zucca, Riccardo; Johansson, Fredrik; Jirenhed, Dan-Anders; Hesslow, Germund

    2015-11-10

    A central tenet of Rescorla and Wagner's model of associative learning is that the reinforcement value of a paired trial diminishes as the associative strength between the presented stimuli increases. Despite its fundamental importance to behavioral sciences, the neural mechanisms underlying the model have not been fully explored. Here, we present findings that, taken together, can explain why a stronger association leads to a reduced reinforcement value, within the context of eyeblink conditioning. Specifically, we show that learned pause responses in Purkinje cells, which trigger adaptively timed conditioned eyeblinks, suppress the unconditional stimulus (US) signal in a graded manner. Furthermore, by examining how Purkinje cells respond to two distinct conditional stimuli and to a compound stimulus, we provide evidence that could potentially help explain the somewhat counterintuitive overexpectation phenomenon, which was derived from the Rescorla-Wagner model.

  20. Selective culture of different types of human parotid gland cells.

    Science.gov (United States)

    Chan, Yen-Hui; Huang, Tsung-Wei; Young, Tai-Horng; Lou, Pei-Jen

    2011-03-01

    Advances in salivary gland tissue engineering can benefit patients diagnosed with xerostomia. Complexity of the gland explains the urgent demand for a reliable protocol to isolate and expand various gland cells that can be used for further study. Three cells with different morphologies were isolated from the same human parotid glands using different culture medium systems and then were identified by the expressions from mRNA to the protein level. Among the 34 specimens, parotid gland acinar cells, myoepithelial cells, and fibroblasts expressing specific markers that belonged to individual cell types, were successfully isolated and expanded from 30 specimens without a complex mechanical process and expensive flow technique. The proposed protocol is simple with a high success rate to culture various gland cells, making it highly promising for use in future tissue engineering studies. Copyright © 2010 Wiley Periodicals, Inc.

  1. Thought Control Ability Is Different from Rumination in Explaining the Association between Neuroticism and Depression: A Three-Study Replication

    OpenAIRE

    Feng-Ying Lu; Wen-Jing Yang; Qing-Lin Zhang; Jiang Qiu

    2017-01-01

    Neuroticism is the most common vulnerability factor of depression. However, the mechanism underlying this vulnerability is still unclear. Previous studies suggested that rumination intensifies the negative effect of neuroticism on depression. However, whether cognitive control could explain the association between neuroticism and depression remains unclear to date. Therefore, this study evaluated the indirect effects of rumination and thought control on the relationship between neuroticism an...

  2. Differences between Lipids Extracted from Five Species Are Not Sufficient To Explain Biomagnification of Nonpolar Organic Chemicals

    DEFF Research Database (Denmark)

    Jahnke, Annika; Holmbäck, Jan; Andersson, Rina Argelia

    2015-01-01

    headspace from spiked olive oil to determine their sorptive capacities. Lipids from seal blubber and pork bacon solely composed of triglycerides had capacities similar to that of olive oil; lipids from mussels, herring, and guillemot egg had quantifiable fractions of phospholipids and cholesterol and showed...... capacities reduced by factors of up to 2.3-fold. Generally, the sorptive capacities of the lipids were not elevated relative to the olive oil controls and are unlikely to explain a substantial part of biomagnification....

  3. Differing Causes of Lactic Acidosis and Deep Breathing in Cerebral Malaria and Severe Malarial Anemia May Explain Differences in Acidosis-Related Mortality.

    Science.gov (United States)

    Brand, Nathan R; Opoka, Robert O; Hamre, Karen E S; John, Chandy C

    Lactic acidosis (LA) is a marker for mortality in severe malaria, but the mechanisms that lead to LA in the different types of severe malaria and the extent to which LA-associated mortality differs by type of severe malaria are not well described. We assessed the frequency of LA in children admitted to Mulago Hospital, Kampala, Uganda with cerebral malaria (CM, n = 193) or severe malarial anemia (SMA, n = 216). LA was compared to mortality and measures of parasite biomass and sequestration (P. falciparum histidine-rich protein-2 (PfHRP2) concentration, platelet count), and to a measure of systemic tissue oxygen delivery (hemoglobin level). LA was more frequent in children with SMA than CM (SMA, 47.7%, CM, 34.2%, P = 0.006), but mortality was higher in children with CM (13.0%) than SMA (0.5%, P<0.0001). In CM, LA was associated with increased PfHRP2 concentration and decreased platelet count but was not associated with hemoglobin level. In contrast, in SMA, LA was associated with a decreased hemoglobin level, but was not associated with PfHRP2 concentration or platelet count. LA was related to mortality only in CM. In multivariable regression analysis of the effect PfHRP2 and hemoglobin levels on LA and DB, only PfHRP2 level increased risk of LA and DB in CM, while in SMA, elevated hemoglobin strongly decreased risk of LA and DB, and PfHRP2 level modestly increased risk of LA. The study findings suggest that LA in CM is due primarily to parasite sequestration, which currently has no effective adjunctive therapy, while LA in SMA is due primarily to anemia, which is rapidly corrected with blood transfusion. Differing etiologies of LA in CM and SMA may explain why LA is associated with mortality in CM but not SMA.

  4. Differences in game reading between selected and non-selected youth soccer players.

    Science.gov (United States)

    Den Hartigh, Ruud J R; Van Der Steen, Steffie; Hakvoort, Bas; Frencken, Wouter G P; Lemmink, Koen A P M

    2018-02-01

    Applying an established theory of cognitive development-Skill Theory-the current study compares the game-reading skills of youth players selected for a soccer school of a professional soccer club (n = 49) and their non-selected peers (n = 38). Participants described the actions taking place in videos of soccer game plays, and their verbalisations were coded using Skill Theory. Compared to the non-selected players, the selected players generally demonstrated higher levels of complexity in their game-reading, and structured the information of game elements-primarily the player, teammate and field-at higher complexity levels. These results demonstrate how Skill Theory can be used to assess, and distinguish game-reading of youth players with different expertise, a skill important for soccer, but also for other sports.

  5. Differences in gender performance on competitive physics selection tests

    Directory of Open Access Journals (Sweden)

    Kate Wilson

    2016-08-01

    Full Text Available [This paper is part of the Focused Collection on Gender in Physics.] We have investigated gender differences in performance over the past eight years on the Australian Science Olympiad Exam (ASOE for physics, which is taken by nearly 1000 high school students each year. The ASOE, run by Australian Science Innovations (ASI, is the initial stage of the process of selection of teams to represent Australia at the Asian and International Physics Olympiads. Students taking the exam are generally in their penultimate year of school and selected by teachers as being high performing in physics. Together with the overall differences in facility, we have investigated how the content and presentation of multiple-choice questions (MCQs affects the particular answers selected by male and female students. Differences in the patterns of responses by male and female students indicate that males and females might be modeling situations in different ways. Some strong patterns were found in the gender gaps when the questions were categorized in five broad dimensions: content, process required, difficulty, presentation, and context. Almost all questions saw male students performing better, although gender differences were relatively small for questions with a more abstract context. Male students performed significantly better on most questions with a concrete context, although notable exceptions were found, including two such questions where female students performed better. Other categories that showed consistently large gaps favoring male students include questions with projectile motion and other two-dimensional motion or forces content, and processes involving interpreting diagrams. Our results have important implications, suggesting that we should be able to reduce the gender gaps in performance on MCQ tests by changing the way information is presented and setting questions in contexts that are less likely to favor males over females. This is important as MCQ

  6. Sparkling feather reflections of a bird-of-paradise explained by finite-difference time-domain modeling

    NARCIS (Netherlands)

    Wilts, Bodo D; Michielsen, Kristel; De Raedt, Hans; Stavenga, Doekele G

    2014-01-01

    Birds-of-paradise are nature's prime examples of the evolution of color by sexual selection. Their brilliant, structurally colored feathers play a principal role in mating displays. The structural coloration of both the occipital and breast feathers of the bird-of-paradise Lawes' parotia is produced

  7. Marriage-Market Constraints and Mate-Selection Behavior: Racial, Ethnic, and Gender Differences in Intermarriage.

    Science.gov (United States)

    Choi, Kate H; Tienda, Marta

    2017-04-01

    Despite theoretical consensus that marriage markets constrain mate selection behavior, few studies directly evaluate how local marriage market conditions influence intermarriage patterns. Using data from the American Community Survey, we examine what aspects of marriage markets influence mate selection; assess whether the associations between marriage market conditions and intermarriage are uniform by gender and across pan-ethnic groups; and investigate the extent to which marriage market conditions account for group differences in intermarriage patterns. Relative group size is the most salient and consistent determinant of intermarriage patterns across pan-ethnic groups and by gender. Marriage market constraints typically explain a larger share of pan-ethnic differences in intermarriage rates than individual traits, suggesting that scarcity of co-ethnic partners is a key reason behind decisions to intermarry. When faced with market constraints, men are more willing or more successful than women in crossing racial and ethnic boundaries in marriage.

  8. Risk behaviors and sports facilities do not explain socioeconomic differences in childhood obesity: a cross-sectional study.

    Science.gov (United States)

    Albaladejo, Romana; Villanueva, Rosa; Navalpotro, Lourdes; Ortega, Paloma; Astasio, Paloma; Regidor, Enrique

    2014-11-19

    To assess whether the relationship between neighborhood socioeconomic context of residence and childhood obesity is explained by family socioeconomic position, risk behaviors and availability of sports facilities. Based on the income and educational level of residents in the neighborhoods of the city of Madrid, two indicators of socioeconomic context were calculated using the information about income and education and grouped into quartiles. In a sample of 727 children aged 6-15 years, the relationship of these indicators with overweight and obesity was studied using multilevel logit models. With respect to children and adolescents living in neighborhoods having higher per capita incomes or higher population percentages with university education those living in neighborhoods having lower per capita incomes or lower population percentages with university education had age- and sex-adjusted odds ratios (ORs) of overweight that were 1.84 (95% CI, 1.03-3.29) and 1.68 (0.95-2.94) times higher, respectively. After adjustment for family socioeconomic position, unhealthy diet and physical inactivity, these ORs fell to 1.80 (0.99-3.29) and 1.56 (0.87-2.79), respectively. In the case of obesity, the age- and sex-adjusted ORs in these quartiles of both indicators of socioeconomic context were 3.35 (1.06-10.60) and 3.29 (1.03-10.52), respectively, rising to 3.77 (1.12-12.70) and 3.42 (1.00-11.68) after adjustment for the remaining variables. The highest OR was observed in the third quartile, except in the case of the relationship between per capita income and obesity. No relationship between the number of sport facilities per 1,000 population and physical inactivity was observed. The socioeconomic context is associated with obesity but not with overweight children in Madrid. The relationship is not explained by family socioeconomic position, risk behaviors and availability of sports facilities.

  9. Explaining sex differences in reactions to relationship infidelities: comparisons of the roles of sex, gender, beliefs, attachment, and sociosexual orientation.

    Science.gov (United States)

    Brase, Gary L; Adair, Lora; Monk, Kale

    2014-02-04

    To the extent that sex differences are mediated by mechanisms such as sex-roles and beliefs, individual differences in these more proximate traits should account for significant portions of relevant sex differences. Differences between women and men in reactions to sexual and emotional infidelity were assessed in a large sample of participants (n = 477), and these target reactions were evaluated as a function of many potential proximate mediators (infidelity implications beliefs, gender-role beliefs, interpersonal trust, attachment style, sociosexuality, and culture of honor beliefs) and as a function of participant sex. Results found a consistent sex difference that was not mediated by any other variables, although a handful of other variables were related to male, but not female, individual differences. These findings suggest particularly promising directions for future research on integrating evolutionarily based sex differences and proximate individual differences.

  10. Episodic nucleotide substitutions in seasonal influenza virus H3N2 can be explained by stochastic genealogical process without positive selection.

    Science.gov (United States)

    Kim, Kangchon; Kim, Yuseob

    2015-03-01

    Nucleotide substitutions in the HA1 domain of seasonal influenza virus H3N2 occur in temporal clusters, which was interpreted as a result of recurrent selective sweeps underlying antigenic drift. However, classical theory by Watterson suggests that episodic substitutions are mainly due to stochastic genealogy combined with unique genetic structure of influenza virus: High mutation rate over a nonrecombining viral segment. This explains why even larger variance in the number of allelic fixations per year is observed in nonantigenic gene segments of H3N2 than in antigenic (hemagglutinin and neuraminidase) segments. Using simulation, we confirm that allelic substitutions at nonrecombining segments with high mutation rate become temporally clustered without selection. We conclude that temporal clustering of fixations, as it is primarily caused by inherent randomness in genealogical process at linked sites, cannot be used as an evidence of positive selection in the H3N2 population. This effect of linkage and high mutation rate should be carefully considered in analyzing the genomic patterns of allelic substitutions in asexually reproducing systems in general. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Sexual Selection and the Evolution of Human Sex Differences

    Directory of Open Access Journals (Sweden)

    David C. Geary

    2006-12-01

    Full Text Available Darwin’s (1871 theory of sexual selection and the associated mechanisms of intrasexual competition (e.g., male-male competition and intersexual choice (e.g., female choice of mates have guided the scientific study of sex differences in hundreds of non-human species. These mechanisms and several recent advances in our understanding of the evolution and expression of sex differences in non-human species are described. The usefulness of this theory for approaching the study human sex differences is illustrated with discussion of patterns of women’s mate preferences and choices and with discussion of men’s one-on-one and coalitional competition. A comparison of these aspects of intersexual choice and intrasexual competition in humans and non-human species is provided, as is discussion of cultural variation in the expression of these behaviors. cultural influences (Maccoby & Jacklin, 1974.

  12. Optimal portfolio selection between different kinds of Renewable energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Zakerinia, MohammadSaleh; Piltan, Mehdi; Ghaderi, Farid

    2010-09-15

    In this paper, selection of the optimal energy supply system in an industrial unit is taken into consideration. This study takes environmental, economical and social parameters into consideration in modeling along with technical factors. Several alternatives which include renewable energy sources, micro-CHP systems and conventional system has been compared by means of an integrated model of linear programming and three multi-criteria approaches (AHP, TOPSIS and ELECTRE III). New parameters like availability of sources, fuels' price volatility, besides traditional factors are considered in different scenarios. Results show with environmental preferences, renewable sources and micro-CHP are good alternatives for conventional systems.

  13. Can Gender Differences in Educational Performance of 15-Year-Old Migrant Pupils Be Explained by Societal Gender Equality in Origin and Destination Countries?

    Science.gov (United States)

    Dronkers, Jaap; Kornder, Nils

    2015-01-01

    In this paper, we attempt to explain the differences between reading and math scores of migrants' children (8430 daughters and 8526 sons) in 17 OECD destination countries, coming from 45 origin countries or regions, using PISA 2009 data. In addition to the societal gender equality levels of the origin and destination countries (the gender…

  14. Can gender differences in the educational performance of 15-year old migrant pupils be explained by the gender equality in the countries of origin and destination?

    NARCIS (Netherlands)

    Dronkers, J.; Kornder, N.

    2013-01-01

    We try to explain the differences between the performance (in both reading and math) of 8430 15-year-old daughters and 8526 15-year-old sons in 17 Organisation for Economic Co-operation and Development destination countries across Europe and Oceania with the PISA 2009 data from 45 origin countries

  15. Can gender differences in the educational performance of 15-year old migrant pupils be explained by the gender equality in the countries of origin and destination?

    NARCIS (Netherlands)

    Dronkers, J.; Kornder, N.

    2013-01-01

    We try to explain the differences between the performance (in both reading and math) of 8430 15-year-old daughters and 8526 15-year-old sons in 17 Organisation for Economic Cooperation and Development destination countries across Europe and Oceania with the PISA 2009 data from 45 origin countries or

  16. Self-Reported Harassment and Bullying in Australian Universities: Explaining Differences between Regional, Metropolitan and Elite Institutions

    Science.gov (United States)

    Skinner, Timothy C.; Peetz, David; Strachan, Glenda; Whitehouse, Gillian; Bailey, Janis; Broadbent, Kaye

    2015-01-01

    We analyse data from the largest survey of university staff in Australia to determine whether bullying and harassment are more common in regional than metropolitan and Go8 universities, and to what extent any differences could be attributed to other factors. While professional staff showed no difference in harassment rates between regional and…

  17. Can Differences in Word Frequency Explain Why Narrative Fiction is a Better Predictor of Verbal Ability than Nonfiction?

    Science.gov (United States)

    McCreath, Graham A.; Linehan, Cormac M. J.; Mar, Raymond A.

    2017-01-01

    Individuals who read more tend to have stronger verbal skills than those who read less. Interestingly, what you read may make a difference. Past studies have found that reading narrative fiction, but not expository nonfiction, predicts verbal ability. Why this difference exists is not known. Here we investigate one possibility: whether fiction…

  18. Differences in neurohormonal activity partially explain the obesity paradox in patients with heart failure: The role of sympathetic activation.

    Science.gov (United States)

    Farré, Núria; Aranyó, Júlia; Enjuanes, Cristina; Verdú-Rotellar, José María; Ruiz, Sonia; Gonzalez-Robledo, Gina; Meroño, Oona; de Ramon, Marta; Moliner, Pedro; Bruguera, Jordi; Comin-Colet, Josep

    2015-02-15

    Obese patients with chronic Heart Failure (HF) have better outcome than their lean counterparts, although little is known about the pathophysiology of this obesity paradox. Our aim was to evaluate the hypothesis that patients with chronic HF and obesity (defined as body mass index (BMI)≥30kg/m(2)), may have an attenuated neurohormonal activation in comparison with non-obese patients. The present study is the post-hoc analysis of a cohort of 742 chronic HF patients from a single-center study evaluating sympathetic activation by measuring baseline levels of norepinephrine (NE). Obesity was present in 33% of patients. Higher BMI and obesity were significantly associated with lower NE levels in multivariable linear regression models adjusted for covariates (p70th percentile) carrying out a separate analysis in obese and non-obese patients we found that in both groups NE remained a significant independent predictor of poorer outcomes, despite the lower NE levels in patients with chronic HF and obesity: all-cause mortality hazard ratio=2.37 (95% confidence interval, 1.14-4.94) and hazard ratio=1.59 (95% confidence interval, 1.05-2.4) in obese and non-obese respectively; and cardiovascular mortality hazard ratio=3.08 (95% confidence interval, 1.05-9.01) in obese patients and hazard ratio=2.08 (95% confidence interval, 1.42-3.05) in non-obese patients. Patients with chronic HF and obesity have significantly lower sympathetic activation. This finding may partially explain the obesity paradox described in chronic HF patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Different Selection Pressures Give Rise to Distinct Ethnic Phenomena

    Science.gov (United States)

    Moya, Cristina; Boyd, Robert

    2015-01-01

    Many accounts of ethnic phenomena imply that processes such as stereotyping, essentialism, ethnocentrism, and intergroup hostility stem from a unitary adaptation for reasoning about groups. This is partly justified by the phenomena’s co-occurrence in correlational studies. Here we argue that these behaviors are better modeled as functionally independent adaptations that arose in response to different selection pressures throughout human evolution. As such, different mechanisms may be triggered by different group boundaries within a single society. We illustrate this functionalist framework using ethnographic work from the Quechua-Aymara language boundary in the Peruvian Altiplano. We show that different group boundaries motivate different ethnic phenomena. For example, people have strong stereotypes about socioeconomic categories, which are not cooperative units, whereas they hold fewer stereotypes about communities, which are the primary focus of cooperative activity. We also show that, despite the cross-cultural importance of ethnolinguistic boundaries, the Quechua-Aymara linguistic distinction does not strongly motivate any of these intergroup processes. PMID:25731969

  20. To be entrepreneurial, or not to be entrepreneurial? Explaining differences in franchisee entrepreneurial behavior within a franchise system

    NARCIS (Netherlands)

    Croonen, Evelien P.M.; Brand, Maryse J.; Huizingh, Eelko K.R.E.

    Although franchising scholars largely acknowledge that franchisees may behave like entrepreneurs, little is known about whether and why franchisees differ in their entrepreneurial behaviors. Franchisees are semi-autonomous entrepreneurs running geographically dispersed units within established

  1. How Different Medical School Selection Processes Call upon Different Personality Characteristics

    Science.gov (United States)

    Schripsema, Nienke R.; van Trigt, Anke M.; van der Wal, Martha A.; Cohen-Schotanus, Janke

    2016-01-01

    Background Research indicates that certain personality traits relate to performance in the medical profession. Yet, personality testing during selection seems ineffective. In this study, we examine the extent to which different medical school selection processes call upon desirable personality characteristics in applicants. Methods 1019 of all 1055 students who entered the Dutch Bachelor of Medicine at University of Groningen, the Netherlands in 2009, 2010 and 2011 were included in this study. Students were admitted based on either top pre-university grades (n = 139), acceptance in a voluntary multifaceted selection process (n = 286), or lottery weighted for pre-university GPA. Within the lottery group, we distinguished between students who had not participated (n = 284) and students who were initially rejected (n = 310) in the voluntary selection process. Two months after admission, personality was assessed with the NEO-FFI, a measure of the five factor model of personality. We performed ANCOVA modelling with gender as a covariate to examine personality differences between the four groups. Results The multifaceted selection group scored higher on extraversion than all other groups(plottery-admitted groups(plottery-admitted group that had not participated in the voluntary selection process. The latter group scored lower on conscientiousness than all other groups(pstatistically significant, were relatively small. Personality scores in the group admitted through the voluntary multifaceted selection process seemed most fit for the medical profession. Personality scores in the lottery-admitted group that had not participated in this process seemed least fit for the medical profession. It seems that in order to select applicants with suitable personalities, an admission process that calls upon desirable personality characteristics is beneficial. PMID:26959489

  2. MC1R diversity in Northern Island Melanesia has not been constrained by strong purifying selection and cannot explain pigmentation phenotype variation in the region.

    Science.gov (United States)

    Norton, Heather L; Werren, Elizabeth; Friedlaender, Jonathan

    2015-10-19

    recent population history of the region, may explain the observed frequencies of the derived rs2228479 allele. These results emphasize the complex genetic architecture of pigmentation phenotypes, which are controlled by multiple, possibly interacting loci. They also highlight the role that population history can play in influencing phenotypic diversity in the absence of strong natural selection.

  3. Dietary patterns explaining differences in bone mineral density and hip structure in the elderly: the Rotterdam Study.

    Science.gov (United States)

    de Jonge, Ester Al; Kiefte-de Jong, Jessica C; Hofman, Albert; Uitterlinden, André G; Kieboom, Brenda Ct; Voortman, Trudy; Franco, Oscar H; Rivadeneira, Fernando

    2017-01-01

    Evidence on the association between dietary patterns, measures of hip bone geometry, and subsequent fracture risk are scarce. The objective of this study was to evaluate whether dietary patterns that explain most variation in bone mineral density (BMD) and hip bone geometry are associated with fracture risk. We included 4028 subjects aged ≥55 y from the Rotterdam study. Intake of 28 food groups was assessed with the use of food-frequency questionnaires. BMD, bone width, section modulus (SM; reflecting bending strength) and cortical buckling ratio (BR; reflecting bone instability) were measured with the use of dual-energy X-ray absorptiometry. BMD and geometry-specific dietary patterns were identified with the use of reduced rank regression. Fracture data were reported by general practitioners (median follow-up 14.8 y). We identified 4 dietary patterns. Of the 4, we named 2 patterns "fruit, vegetables, and dairy" and "sweets, animal fat, and low meat," respectively. These 2 patterns were used for further analysis. Independently of confounders, adherence to the fruit, vegetables, and dairy pattern was associated with high BMD, high SM, low BR, and low risk of fractures [HR (95% CI) for osteoporotic fractures: 0.90 (0.83, 0.96); for hip fractures: 0.85 (0.81, 0.89) per z score of dietary pattern adherence]. Adherence to the sweets, animal fat, and low meat pattern was associated with high bone width, high SM, high BR, and high risk of fractures [HR (95% CI) for osteoporotic fractures: 1.08 (1.00, 1.06); for hip fractures: 1.06 (1.02, 1.12) per z score]. The fruit, vegetables, and dairy pattern might be associated with lower fracture risk because of high BMD, high bending strength, and more stable bones. The sweets, animal fat, and low meat pattern might be associated with higher fracture risk because of widened, unstable bones, independently of BMD. Dietary recommendations associated with bone geometry in addition to BMD might influence risk of fractures. © 2017

  4. A question of balance: Explaining differences between parental and grandparental perspectives on preschoolers' feeding and physical activity.

    Science.gov (United States)

    Eli, Karin; Howell, Kyndal; Fisher, Philip A; Nowicka, Paulina

    2016-04-01

    Although one quarter of US and UK families rely on grandparents as the main providers of informal childcare, grandparental perspectives on the feeding and physical activity of young children remain understudied. The study's aim was to elucidate parents' and grandparents' perspectives on young children's feeding and physical activity, and identify how they negotiate potential differences between these perspectives. We interviewed 22 parents and 27 grandparents from 16 families of children aged 3-5 years in the Pacific Northwest, US. Using familial homeostasis as a novel theoretical framework, the interviews were analyzed to assess differences between parental and grandparental perspectives on feeding and physical activity. The analysis yielded six thematic categories: (1) disagreements about feeding stem from parents' and grandparents' differing definitions of healthy feeding; (2) differences between parents' and grandparents' feeding practices reflect differences in perceived caretaking roles; (3) parents and grandparents negotiate differences in feeding practices through grandparental compliance and parental compromise; (4) differences in preschoolers' physical activity are influenced by parents' and grandparents' own access to and engagement in physical activity; (5) parents and grandparents express few disagreements about preschoolers' screen-time; (6) parents and grandparents rarely discuss preschoolers' physical activity. The findings suggest that parental and grandparental decision-making about feeding and exercise is informed by ideas of what constitutes familial balance and a balanced lifestyle for a preschool aged child, rather than by the child's weight status. Parents and grandparents appear to engage in practices designed to preserve familial homeostasis, which may provide a compelling explanation for the persistent difficulties in implementing family-based childhood obesity interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Racial and ethnic differences in the home food environment explain disparities in dietary practices of middle school children in Texas.

    Science.gov (United States)

    Ranjit, Nalini; Evans, Alexandra E; Springer, Andrew E; Hoelscher, Deanna M; Kelder, Steve H

    2015-01-01

    To examine racial and ethnic differences among middle school children in the home food environment (HFE) and the extent to which associations of healthy and unhealthy eating with the HFE differ by race and ethnicity. Cross-sectional secondary analyses of baseline data from Coordinated Approach to Child Health Middle School, a school-based intervention targeting obesity and obesogenic behaviors among middle school children in Austin, TX. A total of 2,502 children (mean age, 13.9 years; 58% Hispanic, 28% white, and 14% black). Availability and accessibility of healthy foods, and parental support of healthy eating, and family meals. Consumption of both healthy and unhealthy foods was examined. Differences across racial and ethnic groups in aspects of HFE were estimated using linear regression. Models also examined racial and ethnic differences in consumption of healthy and unhealthy foods. If adjusting for HFE, such differences were accounted for. White children had significantly better HFEs than Hispanic and black children with greater availability and accessibility of healthy foods (P foods but not in consumption of unhealthy foods. Improved HFE may increase healthy eating among ethnic minorities but is unlikely to reduce unhealthy eating. Copyright © 2015 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  6. Sex differences in parental care: Gametic investment, sexual selection, and social environment.

    Science.gov (United States)

    Liker, András; Freckleton, Robert P; Remeš, Vladimir; Székely, Tamás

    2015-11-01

    Male and female parents often provide different type and amount of care to their offspring. Three major drivers have been proposed to explain parental sex roles: (1) differential gametic investment by males and females that precipitates into sex difference in care, (2) different intensity of sexual selection acting on males and females, and (3) biased social environment that facilitates the more common sex to provide more care. Here, we provide the most comprehensive assessment of these hypotheses using detailed parental care data from 792 bird species covering 126 families. We found no evidence for the gametic investment hypothesis: neither gamete sizes nor gamete production by males relative to females was related to sex difference in parental care. However, sexual selection correlated with parental sex roles, because the male share in care relative to female decreased with both extra-pair paternity and frequency of male polygamy. Parental sex roles were also related to social environment, because male parental care increased with male-biased adult sex ratios (ASRs). Taken together, our results are consistent with recent theories suggesting that gametic investment is not tied to parental sex roles, and highlight the importance of both sexual selection and ASR in influencing parental sex roles. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  7. Positional Differences in Elite Basketball: Selecting Appropriate Training - Load Measures.

    Science.gov (United States)

    Svilar, Luka; Castellano, Julen; Jukic, Igor; Casamichana, David

    2018-01-18

    The purpose of this paper was to study the structure of interrelationships among external training load measures and how these vary among different positions in elite basketball. Eight external variables of jumping (JUMP), acceleration (ACC), deceleration (DEC) and change of direction (COD), and two internal load variables (RPE and sRPE) were collected from 13 professional players with 300 session records. Three playing positions were considered: guards (n=4), forwards (n=4) and centers (n=5). High and total external variables (hJUMP and tJUMP, hACC and tACC, hDEC and tDEC, hCOD and tCOD) were used for the principal component analysis. Extraction criteria were set at the eigenvalue of greater than one. Varimax rotation mode was used to extract multiple principal components. The analysis showed that all positions had two or three principal components (explaining almost all of the variance), but the configuration of each factor was different: tACC, tDEC, tCOD and hJUMP for centers, hACC, tACC, tCOD and hJUMP for guards, and tACC, hDEC, tDEC, hCOD, and tCOD for forwards are specifically demanded in training sessions and, therefore, these variables must be prioritized in load monitoring. Furthermore, for all playing positions, RPE and sRPE have high correlation with the total amount of ACC, DEC and COD. This would suggest that, although players perform the same training tasks, the demands of each position can vary. A particular combination of external load measures is required to describe training load of each playing position, especially to better understand internal responses among players.

  8. Discrepancy in socioeconomic status does not fully explain the variation in diet quality between consumers of different coffee types.

    Science.gov (United States)

    Wong, Tommy Hon Ting; Sui, Zhixian; Rangan, Anna; Louie, Jimmy Chun Yu

    2017-06-21

    Habitual consumers of different coffee types may vary in socioeconomic status (SES), which is an important determinant of diet quality. Nonetheless, research on diet quality among coffee consumers was scarce. We aimed to compare the diet quality of coffee consumers with different preferences towards coffee type and additive usage. In this cross-sectional analysis, intake data of food, coffee, and additive usage from the adult respondents of the 2011-2012 Australian Health Survey were used. Participants were grouped according to the type of coffee (espresso and ground coffee, E&G; coffee made from coffee mixes and instant coffee, M&I; non-consumers, NC) and additives (milk, sugar, and intense sweetener) consumed. Adjusted food group intake was compared between consumption groups using general linear model. E&G drinkers had better SES than M&I and NC. After adjusting for covariates, the mean dairy intake of E&G drinkers was 22.2% higher than M&I drinkers (p consumers' different preferences towards coffee type and additive usages reflected significant variations in their diet quality, even after adjustment of SES. Therefore, future epidemiological studies should consider separating coffee drinkers according to their habitual consumption of different types of coffee.

  9. A Model to Explain At-Risk/Problem Gambling among Male and Female Adolescents: Gender Similarities and Differences

    Science.gov (United States)

    Donati, Maria Anna; Chiesi, Francesca; Primi, Caterina

    2013-01-01

    This study aimed at testing a model in which cognitive, dispositional, and social factors were integrated into a single perspective as predictors of gambling behavior. We also aimed at providing further evidence of gender differences related to adolescent gambling. Participants were 994 Italian adolescents (64% Males; Mean age = 16.57).…

  10. Hydration Differences Explain the Large Variations in the Complexation Thermodynamics of Modified γ-Cyclodextrins with Bile Salts

    DEFF Research Database (Denmark)

    Køhler, Jonatan; Schönbeck, Jens Christian Sidney; Westh, Peter

    2016-01-01

    The structure and thermodynamics of inclusion complexes of seven different γ-cyclodextrins (γCDs) and three biologically relevant bile salts (BS) were investigated in the present study. Natural γCD and six modified γCDs [two methyl-γCDs, one sulfobutyl ether-γCD (SBEγCD), and three 2-hydroxypropy...

  11. Can behavioural differences in Platypus cylindrus (Coleoptera: Platypodinae) from Portugal and Tunisia be explained by genetic and morphological traits?

    Science.gov (United States)

    Bellahirech, A; Inácio, M L; Nóbrega, F; Henriques, J; Bonifácio, L; Sousa, E; Ben Jamâa, M L

    2016-02-01

    Platypus cylindrus is an important wood borer of cork oak trees (Quercus suber) in the Mediterranean region, namely Portugal, Morocco and Algeria where its presence has drastically increased in the past few decades. On the contrary, the insect is not a relevant pest in Tunisia. The aim of this work is to analyze morphological and genetic differences among Tunisian and Portuguese populations in order to understand their role in the diverse population dynamics (e.g., aggressiveness) of the insect. The information could be used as a novel tool to implement protective measures. Insects were collected from cork oak stands in Tunisia (Ain Beya, Babouch and Mzara) and Portugal (Chamusca and Crato). Morphological traits of female and male mycangial pits were determined, using scanning electron microscopy but no significant differences were found. Genetic differences were analyzed using nuclear (internal simple sequence repeat polymerase chain reaction) and mitochondrial (cytochrome oxidase I (COI)) molecular markers. The results showed a very low level of intraspecific polymorphism and genetic diversity. The alignment of COI sequences showed high percentage of identical sites (99%) indicating a very low variation in nucleotide composition. Other variables related with the ecology of the insect and its associated fungi must be studied for a better understanding of the differences in the insect population's dynamic in Mediterranean countries.

  12. The ABCs of Depression: Integrating Affective, Biological, and Cognitive Models to Explain the Emergence of the Gender Difference in Depression

    Science.gov (United States)

    Hyde, Janet Shibley; Mezulis, Amy H.; Abramson, Lyn Y.

    2008-01-01

    In adulthood, twice as many women as men are depressed, a pattern that holds in most nations. In childhood, girls are no more depressed than boys, but more girls than boys are depressed by ages 13 to 15. Although many influences on this emergent gender difference in depression have been proposed, a truly integrated, developmental model is lacking.…

  13. Explaining educational differences in leisure-time physical activity in Europe: the contribution of work-related factors

    NARCIS (Netherlands)

    Mäkinen, T. E.; Sippola, R.; Borodulin, K.; Rahkonen, O.; Kunst, A.; Klumbiene, J.; Regidor, E.; Ekholm, O.; Mackenbach, J.; Prättälä, R.

    2012-01-01

    Although educational differences in leisure-time physical activity (LTPA) exist across Europe, the independent effect of educational level on leisure-time physical activity has rarely been explored. This study examines the relative contribution of occupational class, employment status, and

  14. Sexual orientation and health : general and minority stress factors explaining health differences between lesbian, gay, bisexual and heterosexual individuals

    NARCIS (Netherlands)

    Kuyper, L.S.

    2011-01-01

    Previous studies show that lesbian, gay and bisexual (LGB) individuals report more health problems than heterosexual individuals. However, several important gaps remain in the knowledge regarding the explanations for these health differences. In general, there is a lack of differentiation between

  15. Explaining Social Class Inequalities in Educational Achievement in the UK: Quantifying the Contribution of Social Class Differences in School "Effectiveness"

    Science.gov (United States)

    Hobbs, Graham

    2016-01-01

    There are large social class inequalities in educational achievement in the UK. This paper quantifies the contribution of one mechanism to the production of these inequalities: social class differences in school "effectiveness," where "effectiveness" refers to a school's impact on pupils' educational achievement (relative to…

  16. Educational Decentralization and Its Implications for Governance: Explaining the Differences in the Four Asian Newly Industrialized Economies

    Science.gov (United States)

    Lo, William Yat Wai

    2010-01-01

    This paper views seeking the optimal balance between state strengths and the scope of state functions for "good governance" as the formation of a homogenization-heterogenization matrix of policy initiatives in different social settings. Homogenization refers to a global tendency for institutional changes and governance framework to…

  17. An ancestral miR-1304 allele present in Neanderthals regulates genes involved in enamel formation and could explain dental differences with modern humans.

    Science.gov (United States)

    Lopez-Valenzuela, Maria; Ramírez, Oscar; Rosas, Antonio; García-Vargas, Samuel; de la Rasilla, Marco; Lalueza-Fox, Carles; Espinosa-Parrilla, Yolanda

    2012-07-01

    Genetic changes in regulatory elements are likely to result in phenotypic effects that might explain population-specific as well as species-specific traits. MicroRNAs (miRNAs) are posttranscriptional repressors involved in the control of almost every biological process. These small noncoding RNAs are present in various phylogenetic groups, and a large number of them remain highly conserved at the sequence level. MicroRNA-mediated regulation depends on perfect matching between the seven nucleotides of its seed region and the target sequence usually located at the 3' untranslated region of the regulated gene. Hence, even single changes in seed regions are predicted to be deleterious as they may affect miRNA target specificity. In accordance to this, purifying selection has strongly acted on these regions. Comparison between the genomes of present-day humans from various populations, Neanderthal, and other nonhuman primates showed an miRNA, miR-1304, that carries a polymorphism on its seed region. The ancestral allele is found in Neanderthal, nonhuman primates, at low frequency (~5%) in modern Asian populations and rarely in Africans. Using miRNA target site prediction algorithms, we found that the derived allele increases the number of putative target genes for the derived miRNA more than ten-fold, indicating an important functional evolution for miR-1304. Analysis of the predicted targets for derived miR-1304 indicates an association with behavior and nervous system development and function. Two of the predicted target genes for the ancestral miR-1304 allele are important genes for teeth formation, enamelin, and amelotin. MicroRNA overexpression experiments using a luciferase-based assay showed that the ancestral version of miR-1304 reduces the enamelin- and amelotin-associated reporter gene expression by 50%, whereas the derived miR-1304 does not have any effect. Deletion of the corresponding target sites for miR-1304 in these dental genes avoided their repression

  18. What explains the socioeconomic status gap in activity? Educational differences in determinants of physical activity and screentime

    Directory of Open Access Journals (Sweden)

    Nelli Hankonen

    2017-02-01

    Full Text Available Abstract Background Designing evidence-based interventions to address socioeconomic disparities in health and health behaviours requires a better understanding of the specific explanatory mechanisms. We aimed to investigate a comprehensive range of potential theoretical mediators of physical activity (PA and screen time in different socioeconomic status (SES groups: a high SES group of high school students, and a low SES group of vocational school students. The COM-B system, including the Theoretical Domains Framework (TDF, was used as a heuristic framework to synthesise different theoretical determinants in this exploratory study. Methods Finnish vocational and high school students (N = 659 aged 16–19, responded to a survey assessing psychological, social and environmental determinants of activity (PA and screen time. These determinants are mappable into the COM-B domains: capability, opportunity and motivation. The outcome measures were validated self-report measures for PA and screen time. The statistical analyses included a bootstrapping-based mediation procedure. Results Regarding PA, there were SES differences in all of the COM-B domains. For example, vocational school students reported using less self-monitoring of PA, weaker injunctive norms to engage in regular PA, and fewer intentions than high school students. Mediation analyses identified potential mediators of the SES-PA relationship in all of three domains: The most important candidates included self-monitoring (CI95 for b: 0.19–0.47, identity (0.04–0.25 and material resources available (0.01–0.16. However, SES was not related to most determinants of screentime, where there were mainly gender differences. Most determinants were similarly related with both behaviours in both SES groups, indicating no major moderation effect of SES on these relationships. Conclusions This study revealed that already in the first years of educational differentiation, levels of key PA

  19. What explains the socioeconomic status gap in activity? Educational differences in determinants of physical activity and screentime.

    Science.gov (United States)

    Hankonen, Nelli; Heino, Matti T J; Kujala, Emilia; Hynynen, Sini-Tuuli; Absetz, Pilvikki; Araújo-Soares, Vera; Borodulin, Katja; Haukkala, Ari

    2017-02-01

    Designing evidence-based interventions to address socioeconomic disparities in health and health behaviours requires a better understanding of the specific explanatory mechanisms. We aimed to investigate a comprehensive range of potential theoretical mediators of physical activity (PA) and screen time in different socioeconomic status (SES) groups: a high SES group of high school students, and a low SES group of vocational school students. The COM-B system, including the Theoretical Domains Framework (TDF), was used as a heuristic framework to synthesise different theoretical determinants in this exploratory study. Finnish vocational and high school students (N = 659) aged 16-19, responded to a survey assessing psychological, social and environmental determinants of activity (PA and screen time). These determinants are mappable into the COM-B domains: capability, opportunity and motivation. The outcome measures were validated self-report measures for PA and screen time. The statistical analyses included a bootstrapping-based mediation procedure. Regarding PA, there were SES differences in all of the COM-B domains. For example, vocational school students reported using less self-monitoring of PA, weaker injunctive norms to engage in regular PA, and fewer intentions than high school students. Mediation analyses identified potential mediators of the SES-PA relationship in all of three domains: The most important candidates included self-monitoring (CI95 for b: 0.19-0.47), identity (0.04-0.25) and material resources available (0.01-0.16). However, SES was not related to most determinants of screentime, where there were mainly gender differences. Most determinants were similarly related with both behaviours in both SES groups, indicating no major moderation effect of SES on these relationships. This study revealed that already in the first years of educational differentiation, levels of key PA determinants differ, contributing to socioeconomic differences in PA. The

  20. Explaining educational differences in leisure-time physical activity in Europe: the contribution of work-related factors.

    Science.gov (United States)

    Mäkinen, T E; Sippola, R; Borodulin, K; Rahkonen, O; Kunst, A; Klumbiene, J; Regidor, E; Ekholm, O; Mackenbach, J; Prättälä, R

    2012-06-01

    Although educational differences in leisure-time physical activity (LTPA) exist across Europe, the independent effect of educational level on leisure-time physical activity has rarely been explored. This study examines the relative contribution of occupational class, employment status, and educational level to LTPA across 12 European countries. The data were obtained from 12 European health surveys conducted at the turn of the century and identified in the EUROTHINE project. All information was self-reported. Logistic regression was applied and relative inequality index (RII) was calculated. Analyses were limited to those in the prime working-age (age 30-59; total N=137,646) men and women. In all 12 European countries, LTPA was more common in the high-educated than in the low-educated. The association between education and LTPA remained mostly unchanged after adjusting for marital status, urbanization, and self-rated health. After further adjusting for occupational class and employment status, the educational differences in LTPA were only slightly attenuated. An inverse association was found between educational level and LTPA across almost all 12 European countries. Occupational class and employment status had only a modest effect on educational differences in LTPA in most of the examined countries, suggesting that education remains an important predictor of LTPA. © 2010 John Wiley & Sons A/S.

  1. Gender wage differences in the selected Czech public sector company

    Directory of Open Access Journals (Sweden)

    Veronika Hedija

    2012-01-01

    Full Text Available The issue of wage disparity between men and women belongs to the current and widely discussed topics. The attention given to this subject also reflects the fact that the issue of the equality between women and men and non-discrimination by gender is incorporated in the law of the European Union. A number of studies are devoted to the gender wage disparities and the root cause of wage differences in the Czech Republic, however, only few of these deal with the gender wage differentials in the public sector. It is exactly this issue, which is discussed in this article, its aim being to identify the extent of the gender pay gap in the selected Czech public sector company. The article concentrates on finding the main causes for the existence of wage differences between men and women and determining whether the company inclines to wage discrimination against women. The Oaxaca-Blinder decomposition is used to define, which part of the gender pay gap can be attributed to the different characteristics of men and women and which part stays unexplained. It is this unexplained part that can be the result of wage discrimination against women.

  2. Expression Differences of Pigment Structural Genes and Transcription Factors Explain Flesh Coloration in Three Contrasting Kiwifruit Cultivars

    Directory of Open Access Journals (Sweden)

    Yanfei Liu

    2017-09-01

    Full Text Available Fruits of kiwifruit cultivars (Actinidia chinensis and A. deliciosa generally have green or yellow flesh when ripe. A small number of genotypes have red flesh but this coloration is usually restricted to the inner pericarp. Three kiwifruit cultivars having red (‘Hongyang’, or yellow (‘Jinnong-2’, or green (‘Hayward’ flesh were investigated for their color characteristics and pigment contents during development and ripening. The results show the yellow of the ‘Jinnong-2’ fruit is due to the combined effects of chlorophyll degradation and of beta-carotene accumulation. The red inner pericarps of ‘Hongyang’ fruit are due to anthocyanin accumulation. Expression differences of the pathway genes in the inner pericarps of the three different kiwifruits suggest that stay-green (SGR controls the degradation of chlorophylls, while lycopene beta-cyclase (LCY-β controls the biosynthesis of beta-carotene. The abundance of anthocyanin in the inner pericarps of the ‘Hongyang’ fruit is the results of high expressions of UDP flavonoid glycosyltransferases (UFGT. At the same time, expressions of anthocyanin transcription factors show that AcMYBF110 expression parallels changes in anthocyanin concentration, so seems to be a key R2R3 MYB, regulating anthocyanin biosynthesis. Further, transient color assays reveal that AcMYBF110 can autonomously induce anthocyanin accumulation in Nicotiana tabacum leaves by activating the transcription of dihydroflavonol 4-reductase (NtDFR, anthocyanidin synthase (NtANS and NtUFGT. For basic helix-loop-helix proteins (bHLHs and WD-repeat proteins (WD40s, expression differences show these may depend on AcMYBF110 forming a MYB-bHLH-WD40 complex to regulate anthocyanin biosynthesis, instead of it having a direct involvement.

  3. Morphologic characteristics help explain the gender difference in peak anterior cruciate ligament strain during a simulated pivot landing.

    Science.gov (United States)

    Lipps, David B; Oh, Youkeun K; Ashton-Miller, James A; Wojtys, Edward M

    2012-01-01

    Gender differences exist in anterior cruciate ligament (ACL) cross-sectional area and lateral tibial slope. Biomechanical principles suggest that the direction of these gender differences should induce larger peak ACL strains in females under dynamic loading. Peak ACL relative strain during a simulated pivot landing is significantly greater in female ACLs than male ACLs. Controlled laboratory study. Twenty cadaveric knees from height- and weight-matched male and female cadavers were subjected to impulsive 3-dimensional test loads of 2 times body weight in compression, flexion, and internal tibial torque starting at 15° of flexion. Load cells measured the 3-dimensional forces and moments applied to the knee, and forces in the pretensioned quadriceps, hamstring, and gastrocnemius muscle equivalents. A novel, gender-specific, nonlinear spring simulated short-range and longer range quadriceps muscle tensile stiffness. Peak relative strain in the anteromedial bundle of the ACL (AM-ACL) was measured using a differential variable reluctance transducer, while ACL cross-sectional area and lateral tibial slope were measured using magnetic resonance imaging. A repeated-measures Mann-Whitney signed-rank test was used to test the hypothesis. Female knees exhibited 95% greater peak AM-ACL relative strain than male knees (6.37% [2.53%] vs 3.26% [1.89%]; P = .004). Anterior cruciate ligament cross-sectional area and lateral tibial slope were significant predictors of peak AM-ACL relative strain (R(2) = .59; P = .001). Peak AM-ACL relative strain was significantly greater in female than male knees from donors of the same height and weight. This gender difference is attributed to a smaller female ACL cross-sectional area and a greater lateral tibial slope. Since female ACLs are systematically exposed to greater strain than their male counterparts, training and injury prevention programs should take this fact into consideration.

  4. Explaining educational differences in leisure-time physical activity in Europe: the contribution of work-related factors

    DEFF Research Database (Denmark)

    Mäkinen, T E; Sippola, R; Borodulin, K

    2011-01-01

    Although educational differences in leisure-time physical activity (LTPA) exist across Europe, the independent effect of educational level on leisure-time physical activity has rarely been explored. This study examines the relative contribution of occupational class, employment status......, and educational level to LTPA across 12 European countries. The data were obtained from 12 European health surveys conducted at the turn of the century and identified in the EUROTHINE project. All information was self-reported. Logistic regression was applied and relative inequality index (RII) was calculated...

  5. Explaining the differences in household food waste collection and treatment provisions between local authorities in England and Wales.

    Science.gov (United States)

    Bees, A D; Williams, I D

    2017-12-01

    Separate household food waste collection for anaerobic digestion is one method used in the sustainable management of biodegradable municipal solid waste (MSW). Recycling of food waste contributes to the UK's reuse, recycling and composting targets and can help local authorities boost plateauing rates whilst encouraging landfill diversion. This study explored the reasons for differences in the provision of food waste collections, using two comparable local authorities, one with a collection in Wales (Cardiff), and the other absent of such service in England (Southampton). A PESTLE analysis investigated the political, economic, social, technological, legal and environmental impacts of separate food waste collections. The greenhouse gas impacts of the collection and treatment systems of MSW in both cities were estimated for 2012/13. Results showed significant policy and legislative differences between devolved governments, that separate food waste collections can save local authorities significant sums of money and substantially reduce greenhouse gas impacts. A survey of one hundred respondents in each city aimed to understand attitudes and behaviours towards recycling, food waste segregation, cooking and purchasing habits. The number of frequent recyclers and levels of satisfaction were higher in the authority which provided a separate food waste collection. In the area which lacked a separate collection service, over three-quarters of respondents would participate in such a scheme if it were available. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Summing across different active zones can explain the quasi-linear Ca2+-dependencies of exocytosis by receptor cells

    Directory of Open Access Journals (Sweden)

    Peter Heil

    2010-11-01

    Full Text Available Several recent studies of mature auditory and vestibular hair cells, and of visual and olfactory receptor cells, have observed nearly linear dependencies of the rate of neurotransmitter release events, or related measures, on the magnitude of Ca2+-entry into the cell. These relationships contrast with the highly supra-linear, 3rd to 4th power, Ca2+-dependencies observed in most preparations, from neuromuscular junctions to central synapses, and also in hair cells from immature and various mutant animals. They also contrast with the intrinsic, biochemical, Ca2+-cooperativity of the ubiquitous Ca2+-sensors involved in fast exocytosis (synaptotagmins I and II. Here, we propose that the quasi-linear dependencies result from measuring the sum of several supra-linear, but saturating, dependencies with different sensitivities at individual active zones of the same cell. We show that published experimental data can be accurately accounted for by this summation model, without the need to assume altered Ca2+-cooperativity or nanodomain control of release. We provide support for the proposal that the best power is 3, and we discuss the large body of evidence for our summation model. Overall, our idea provides a parsimonious and attractive reconciliation of the seemingly discrepant experimental findings in different preparations.

  7. Summing Across Different Active Zones can Explain the Quasi-Linear Ca-Dependencies of Exocytosis by Receptor Cells.

    Science.gov (United States)

    Heil, Peter; Neubauer, Heinrich

    2010-01-01

    Several recent studies of mature auditory and vestibular hair cells (HCs), and of visual and olfactory receptor cells, have observed nearly linear dependencies of the rate of neurotransmitter release events, or related measures, on the magnitude of Ca(2+)-entry into the cell. These relationships contrast with the highly supralinear, third to fourth power, Ca(2+)-dependencies observed in most preparations, from neuromuscular junctions to central synapses, and also in HCs from immature and various mutant animals. They also contrast with the intrinsic, biochemical, Ca(2+)-cooperativity of the ubiquitous Ca(2+)-sensors involved in fast exocytosis (synaptotagmins I and II). Here, we propose that the quasi-linear dependencies result from measuring the sum of several supralinear, but saturating, dependencies with different sensitivities at individual active zones of the same cell. We show that published experimental data can be accurately accounted for by this summation model, without the need to assume altered Ca(2+)-cooperativity or nanodomain control of release. We provide support for the proposal that the best power is 3, and we discuss the large body of evidence for our summation model. Overall, our idea provides a parsimonious and attractive reconciliation of the seemingly discrepant experimental findings in different preparations.

  8. Anatomical and diffusional determinants inside leaves explain the difference in photosynthetic capacity between Cypripedium and Paphiopedilum, Orchidaceae.

    Science.gov (United States)

    Yang, Zhong-Hui; Huang, Wei; Yang, Qiu-Yun; Chang, Wei; Zhang, Shi-Bao

    2017-11-20

    Comparing with other angiosperms, most members within the family Orchidaceae have lower photosynthetic capacities. However, the underlying mechanisms remain unclear. Cypripedium and Paphiopedilum are closely related phylogenetically in Orchidaceae, but their photosynthetic performances are different. We explored the roles of internal anatomy and diffusional conductance in determining photosynthesis in three Cypripedium and three Paphiopedilum species, and quantitatively analyzed their diffusional and biochemical limitations to photosynthesis. Paphiopedilum species showed lower light-saturated photosynthetic rate (A N), stomatal conductance (g s), and mesophyll conductance (g m) than Cypripedium species. A N was positively correlated with g s and g m. And yet, in both species A N was more strongly limited by g m than by biochemical factors or g s. The greater g s of Cypripedium was mainly affected by larger stomatal apparatus area and smaller pore depth, while the less g m of Paphiopedilum was determined by the reduced surface area of mesophyll cells and chloroplasts exposed to intercellular airspace per unit of leaf area, and much thicker cell wall thickness. These results suggest that leaf anatomical structure is the key factor affecting g m, which is largely responsible for the difference in photosynthetic capacity between those two genera. Our findings provide new insight into the photosynthetic physiology and functional diversification of orchids.

  9. Spring predictability explains different leaf-out strategies in the woody floras of North America, Europe and East Asia.

    Science.gov (United States)

    Zohner, Constantin M; Benito, Blas M; Fridley, Jason D; Svenning, Jens-Christian; Renner, Susanne S

    2017-04-01

    Intuitively, interannual spring temperature variability (STV) should influence the leaf-out strategies of temperate zone woody species, with high winter chilling requirements in species from regions where spring warming varies greatly among years. We tested this hypothesis using experiments in 215 species and leaf-out monitoring in 1585 species from East Asia (EA), Europe (EU) and North America (NA). The results reveal that species from regions with high STV indeed have higher winter chilling requirements, and, when grown under the same conditions, leaf out later than related species from regions with lower STV. Since 1900, STV has been consistently higher in NA than in EU and EA, and under experimentally short winter conditions NA species required 84% more spring warming for bud break, EU ones 49% and EA ones only 1%. These previously unknown continental-scale differences in phenological strategies underscore the need for considering regional climate histories in global change models. © 2017 John Wiley & Sons Ltd/CNRS.

  10. The biological properties of different Epstein-Barr virus strains explain their association with various types of cancers.

    Science.gov (United States)

    Tsai, Ming-Han; Lin, Xiaochen; Shumilov, Anatoliy; Bernhardt, Katharina; Feederle, Regina; Poirey, Remy; Kopp-Schneider, Annette; Pereira, Bruno; Almeida, Raquel; Delecluse, Henri-Jacques

    2017-02-07

    The Epstein-Barr virus (EBV) is etiologically associated with the development of multiple types of tumors, but it is unclear whether this diversity is due to infection with different EBV strains. We report a comparative characterization of SNU719, GP202, and YCCEL1, three EBV strains that were isolated from gastric carcinomas, M81, a virus isolated in a nasopharyngeal carcinoma and several well-characterized laboratory type A strains. We found that B95-8, Akata and GP202 induced cell growth more efficiently than YCCEL1, SNU719 and M81 and this correlated positively with the expression levels of the viral BHRF1 miRNAs. In infected B cells, all strains except Akata and B95-8 induced lytic replication, a risk factor for carcinoma development, although less efficiently than M81. The panel of viruses induced tumors in immunocompromised mice with variable speed and efficacy that did not strictly mirror their in vitro characteristics, suggesting that additional parameters play an important role. We found that YCCEL1 and M81 infected primary epithelial cells, gastric carcinoma cells and gastric spheroids more efficiently than Akata or B95-8. Reciprocally, Akata and B95-8 had a stronger tropism for B cells than YCCEL1 or M81. These data suggest that different EBV strains will induce the development of lymphoid tumors with variable efficacy in immunocompromised patients and that there is a parallel between the cell tropism of the viral strains and the lineage of the tumors they induce. Thus, EBV strains can be endowed with properties that will influence their transforming abilities and the type of tumor they induce.

  11. Pupil Diameter Tracks the Exploration-Exploitation Trade-off during Analogical Reasoning and Explains Individual Differences in Fluid Intelligence.

    Science.gov (United States)

    Hayes, Taylor R; Petrov, Alexander A

    2016-02-01

    The ability to adaptively shift between exploration and exploitation control states is critical for optimizing behavioral performance. Converging evidence from primate electrophysiology and computational neural modeling has suggested that this ability may be mediated by the broad norepinephrine projections emanating from the locus coeruleus (LC) [Aston-Jones, G., & Cohen, J. D. An integrative theory of locus coeruleus-norepinephrine function: Adaptive gain and optimal performance. Annual Review of Neuroscience, 28, 403-450, 2005]. There is also evidence that pupil diameter covaries systematically with LC activity. Although imperfect and indirect, this link makes pupillometry a useful tool for studying the locus coeruleus norepinephrine system in humans and in high-level tasks. Here, we present a novel paradigm that examines how the pupillary response during exploration and exploitation covaries with individual differences in fluid intelligence during analogical reasoning on Raven's Advanced Progressive Matrices. Pupillometry was used as a noninvasive proxy for LC activity, and concurrent think-aloud verbal protocols were used to identify exploratory and exploitative solution periods. This novel combination of pupillometry and verbal protocols from 40 participants revealed a decrease in pupil diameter during exploitation and an increase during exploration. The temporal dynamics of the pupillary response was characterized by a steep increase during the transition to exploratory periods, sustained dilation for many seconds afterward, and followed by gradual return to baseline. Moreover, the individual differences in the relative magnitude of pupillary dilation accounted for 16% of the variance in Advanced Progressive Matrices scores. Assuming that pupil diameter is a valid index of LC activity, these results establish promising preliminary connections between the literature on locus coeruleus norepinephrine-mediated cognitive control and the literature on analogical

  12. Are there biologic differences between male and female breast cancer explaining inferior outcome of men despite equal stage and treatment?.

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, A.C.; Gani, C.; Rehm, H.M.E.; Eckert, F.; Bamberg, M.; Weinmann, M. [Tuebingen Univ. (Germany). Dept. of Radiooncology; Hehr, T. [Marienhospital Stuttgart (Germany). Dept. of Radiooncology

    2012-09-15

    Background: Reasons for inferior outcome of male compared to female breast cancer are still under debate. Therefore, we retrospectively analyzed male breast cancer cases to figure out possible treatment- and gender-related differences. Patients and methods: A total of 40 men (median age 62 years) were curatively treated with mastectomy and postoperative radiotherapy from 1982-2007. They presented predominantly in stages II and IIIb. Postoperative radiotherapy was applied with doses of 1.8-2.5 Gy to a median of 50 Gy including regional lymphatics in 22 patients. Adjuvant systemic treatment consisted of chemotherapy (22.5%) and antihormonal treatment (55%). For reasons of comparison, we estimated outcome of a virtual female matched cohort for no/equal to men/optimal adjuvant treatment with the Adjuvant.Online {sup registered} 8.0 algorithm. Results: After a median follow-up of 47 months, the estimated 5-year local control rate was 97%, disease-free and distant metastasis-free survival rates reached 79% and 82%, respectively. With update of survival data by tumor registry, mean overall survival reached 120 months with 5- and 10-year overall survival rates of 66% and 43%, respectively. Predominant prognostic factor was T-stage for overall survival (T1/2 vs. T4: > 80% vs. 30%). The generated virtual matched cohorts of women with equal characteristics reached superior 10-year-overall survival for no/equal to men/optimal adjuvant treatment with 55/59/68%. Conclusion: Compared to historical and virtual matched cohorts of women, male breast cancer patients had inferior outcome despite of equal stage and treatment which indicates that biological differences (of tumor or population) may contribute to worse prognosis. (orig.)

  13. Current Data on Risk Factor Estimates Does Not Explain the Difference in Rates of Melanoma between Hispanics and Non-Hispanic Whites

    Directory of Open Access Journals (Sweden)

    Sonia Kamath

    2016-01-01

    Full Text Available United States Hispanics have seven times lower melanoma incidence rates than non-Hispanic whites (NHW. It is unclear whether this difference can be explained solely by phenotypic risk factors, like darker skin, or whether modifiable risk factors, like sun exposure, also play a role. The purpose of this paper is to summarize what is currently known about melanoma risk factors among Hispanics and NHWs, and whether or not those differences could explain the difference in melanoma incidence. Through literature review, relative risks and prevalence of melanoma risk factors in Hispanics and NHWs were identified and used to calculate the expected rate in Hispanics and rate ratio compared to NHWs. We found that melanoma risk factors either have similar frequency in Hispanics and NHWs (e.g., many large nevi or are less frequent in Hispanics but do not explain a high proportion of disease variation (e.g., red hair. Considering current knowledge of risk factor prevalence, we found that melanoma incidence rates in the two groups should actually be similar. Sun exposure behavior among Hispanics may contribute to the explanation for the 7-fold difference in melanoma rates. Currently, limited data exist on sun exposure behavior among Hispanics, but possibilities for improving primary prevention by further studying these practices are substantial.

  14. Explaining primary pupils’ differences in reading achievement by teaching patterns and socioeconomic background - Reanalyses with the PIRLS-data

    Directory of Open Access Journals (Sweden)

    Michael Pfeifer

    2011-12-01

    Full Text Available This contribution presents the outcomes of multilevel analysis in the context of the Progress in International Reading Literacy Study (PIRLS 2001 that are unique in Germany so far. The PIRLS survey 2001 revealed that in Germany especially pupils with a low socioeconomic status (SES and with migration background have a significant lower reading achievement of more than one school year compared to pupils with a high SES and without migration background. The PIRLS survey 2006 evidenced that, although this difference did reduce over the years, there is still a disadvantage for those pupils’ reading achievement of more than one school year. Thus, one of the main research questions of this work was, if there are certain concepts, strategies and methods of teaching, which contribute to a better acquirement of reading achievement of pupils with low socioeconomic and migration background. As a result of the analyses certain aspects of teaching could be identified that contribute to a better reading achievement of those pupils.

  15. Spatial heterogeneity of physicochemical properties explains differences in microbial composition in arid soils from Cuatro Cienegas, Mexico.

    Science.gov (United States)

    Pajares, Silvia; Escalante, Ana E; Noguez, Ana M; García-Oliva, Felipe; Martínez-Piedragil, Celeste; Cram, Silke S; Eguiarte, Luis Enrique; Souza, Valeria

    2016-01-01

    Arid ecosystems are characterized by high spatial heterogeneity, and the variation among vegetation patches is a clear example. Soil biotic and abiotic factors associated with these patches have also been well documented as highly heterogeneous in space. Given the low vegetation cover and little precipitation in arid ecosystems, soil microorganisms are the main drivers of nutrient cycling. Nonetheless, little is known about the spatial distribution of microorganisms and the relationship that their diversity holds with nutrients and other physicochemical gradients in arid soils. In this study, we evaluated the spatial variability of soil microbial diversity and chemical parameters (nutrients and ion content) at local scale (meters) occurring in a gypsum-based desert soil, to gain knowledge on what soil abiotic factors control the distribution of microbes in arid ecosystems. We analyzed 32 soil samples within a 64 m(2) plot and: (a) characterized microbial diversity using T-RFLPs of the bacterial 16S rRNA gene, (b) determined soil chemical parameters, and (c) identified relationships between microbial diversity and chemical properties. Overall, we found a strong correlation between microbial composition heterogeneity and spatial variation of cations (Ca(2), K(+)) and anions (HCO[Formula: see text], Cl(-), SO[Formula: see text]) content in this small plot. Our results could be attributable to spatial differences of soil saline content, favoring the patchy emergence of salt and soil microbial communities.

  16. Can the differences in the determinations of V(ub) and V(cb) be explained by new physics?

    Science.gov (United States)

    Crivellin, Andreas; Pokorski, Stefan

    2015-01-09

    The precise determination of the Cabibbo-Kobayashi-Maskawa elements V(ub) and V(ub) is crucial for any new physics analysis in the flavor sector. Their values can be determined from several tree-level decays: V(ub) can be extracted from B→Dℓν and B→D(*)ℓν while V(ub) can be obtained from B→πℓν, B→ρℓν, and B→τν. In addition, for both V(ub) and V(ub) an inclusive determination is available. There is a long lasting discrepancy between the inclusive and exclusive determinations which recently even increased for V(ub) above the 3σ level. In this Letter we study the possible effect of new physics on the inclusive and exclusive determination of V(ub) and V(ub) in a model independent way. We find that there is only one operator corresponding to a modified W coupling which can achieve this. However, respecting SU(2) gauge invariance at the high scale this would lead to very large violations of the Z to bb̅ coupling not compatible with experiment. Therefore, we conclude that a new physics explanation of the difference between the inclusive and exclusive determination of V(ub) and V(ub) is currently ruled out. Therefore, the discrepancies must be due to underestimated uncertainties in the theoretical and/or the experimental analysis.

  17. Critical realism: a practical ontology to explain the complexities of smoking and tobacco control in different resource settings.

    Science.gov (United States)

    Oladele, Dunsi; Clark, Alexander M; Richter, Solina; Laing, Lory

    2013-04-03

    This paper presents critical realism (CR) as an innovative system for research in tobacco prevention and control. CR argues that underlying mechanisms are considered and explored to ensure effective implementation of any program/policy or intervention. Any intervention or program/policy that is transposed from one country to another or one setting to another is complex. The research was undertaken and analyzed through a critical ethnography lens using CR as a philosophical underpinning. The study relied upon the following components: original fieldwork in Nigeria including participant observation of smokers, in-depth interviews and focus groups with smokers, and in-depth interviews with health professionals working in the area of tobacco control in Nigeria. Findings from this small ethnographic study in Nigeria, suggest that Critical Realism holds promise for addressing underlying mechanism that links complex influences on smoking. This paper argues that understanding the underlying mechanisms associated with smoking in different societies will enable a platform for effective implementation of tobacco control policies that work in various settings.

  18. Spatial heterogeneity of physicochemical properties explains differences in microbial composition in arid soils from Cuatro Cienegas, Mexico

    Directory of Open Access Journals (Sweden)

    Silvia Pajares

    2016-09-01

    Full Text Available Arid ecosystems are characterized by high spatial heterogeneity, and the variation among vegetation patches is a clear example. Soil biotic and abiotic factors associated with these patches have also been well documented as highly heterogeneous in space. Given the low vegetation cover and little precipitation in arid ecosystems, soil microorganisms are the main drivers of nutrient cycling. Nonetheless, little is known about the spatial distribution of microorganisms and the relationship that their diversity holds with nutrients and other physicochemical gradients in arid soils. In this study, we evaluated the spatial variability of soil microbial diversity and chemical parameters (nutrients and ion content at local scale (meters occurring in a gypsum-based desert soil, to gain knowledge on what soil abiotic factors control the distribution of microbes in arid ecosystems. We analyzed 32 soil samples within a 64 m2 plot and: (a characterized microbial diversity using T-RFLPs of the bacterial 16S rRNA gene, (b determined soil chemical parameters, and (c identified relationships between microbial diversity and chemical properties. Overall, we found a strong correlation between microbial composition heterogeneity and spatial variation of cations (Ca2, K+ and anions (HCO ${}_{3}^{-}$ 3 − , Cl−, SO ${}_{4}^{2-}$ 4 2 − content in this small plot. Our results could be attributable to spatial differences of soil saline content, favoring the patchy emergence of salt and soil microbial communities.

  19. Understanding heterogeneity in borderline personality disorder: differences in affective reactivity explained by the traits of dependency and self-criticism.

    Science.gov (United States)

    Kopala-Sibley, Daniel C; Zuroff, David C; Russell, Jennifer J; Moskowitz, D S; Paris, Joel

    2012-08-01

    This study examined whether the personality traits of self-criticism and dependency respectively moderated the effects of perceived inferiority and emotional insecurity on negative affect during interpersonal interactions in individuals with borderline personality disorder (BPD). A sample of 38 patients with BPD and matched community comparison participants completed event-contingent record forms after each significant interaction for a 20-day period. Multilevel models showed that, controlling for baseline levels of depressive symptoms and neuroticism, as well as lagged negative affect, event-level elevations in perceived inferiority and emotional insecurity were related to more negative affect in both groups. Event-level perceived inferiority was more strongly associated with negative affect in patients with BPD who reported higher levels of self-criticism, while event-level perceived emotional insecurity was more strongly associated with negative affect in patients with BPD who reported higher levels of dependency. No significant interactions emerged for the comparison group. These findings further our understanding of differences among patients with BPD and support the application of personality-vulnerability or diathesis-stress models in predicting negative affect in BPD. Results have implications for the design of therapies for patients with BPD. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  20. Differences in the dynamics of serotonin reuptake transporter occupancy may explain superior clinical efficacy of escitalopram versus citalopram.

    Science.gov (United States)

    Kasper, Siegfried; Sacher, Julia; Klein, Nikolas; Mossaheb, Nilufar; Attarbaschi-Steiner, Trawat; Lanzenberger, Rupert; Spindelegger, Christoph; Asenbaum, Susanne; Holik, Alexander; Dudczak, Robert

    2009-05-01

    Escitalopram the S-enantiomer of the racemate citalopram, is clinically more effective than citalopram in the treatment of major depressive disorder. However, the precise mechanism by which escitalopram achieves superiority over citalopram is yet to be determined. It has been hypothesized that the therapeutically inactive R-enantiomer competes with the serotonin-enhancing S-enantiomer at a low-affinity allosteric site on serotonin reuptake transporters (SERTs), and reduces the effectiveness of the S-enantiomer at the primary, high-affinity serotonin-binding site. This study summarizes the results of two recent single-photon emission computerized tomography studies measuring SERT occupancy in citalopram-treated and escitalopram-treated healthy volunteers, after a single dose and multiple doses (i.e. under steady-state conditions). The single-dose study showed no attenuating effect of R-citalopram. After multiple dosing, however, SERT occupancy was significantly reduced in the presence of R-citalopram. Under steady-state conditions, R-enantiomer concentrations were greater than for the S-enantiomer because of slower clearance of R-citalopram. A pooled analysis suggests that build-up of the R-enantiomer after repeated citalopram dosing may lead to increased inhibition of S-enantiomer occupancy of SERT. This review adds to the growing body of evidence regarding differences in the dynamics of SERT occupancy, that is, molecular mechanisms underlying the often-observed superior clinical efficacy of escitalopram compared with citalopram in major depressive disorder.

  1. Feature selection gait-based gender classification under different circumstances

    Science.gov (United States)

    Sabir, Azhin; Al-Jawad, Naseer; Jassim, Sabah

    2014-05-01

    This paper proposes a gender classification based on human gait features and investigates the problem of two variations: clothing (wearing coats) and carrying bag condition as addition to the normal gait sequence. The feature vectors in the proposed system are constructed after applying wavelet transform. Three different sets of feature are proposed in this method. First, Spatio-temporal distance that is dealing with the distance of different parts of the human body (like feet, knees, hand, Human Height and shoulder) during one gait cycle. The second and third feature sets are constructed from approximation and non-approximation coefficient of human body respectively. To extract these two sets of feature we divided the human body into two parts, upper and lower body part, based on the golden ratio proportion. In this paper, we have adopted a statistical method for constructing the feature vector from the above sets. The dimension of the constructed feature vector is reduced based on the Fisher score as a feature selection method to optimize their discriminating significance. Finally k-Nearest Neighbor is applied as a classification method. Experimental results demonstrate that our approach is providing more realistic scenario and relatively better performance compared with the existing approaches.

  2. Bimodal Modulation of Ipsilateral Spinal-Coeruleo-Spinal Pathway in CRPS: A Novel Model for Explaining Different Clinical Features of the Syndrome.

    Science.gov (United States)

    Carcamo, Cesar R

    2015-08-01

    The objective is to present a hypothesis to explain the sensory, autonomic, and motor disturbances associated with complex regional pain syndrome (CRPS) syndrome. The author reviewed the available and relevant literature, which was supplemented with research on experimental animal models, with a focus on how they may translate into humans, particularly in areas about pathophysiologic mechanisms of CRPS. We propose that different CRPS subtypes may result from facilitative or inhibitory influences exerted by the spinal-coeruleo-spinal pathway in three sites at the spinal cord: the dorsal horn (DH), intermediolateral cell column (IML) and ventral horn (VH). A facilitatory influence over DH may have a pronociceptive effect that explains exacerbated pain, sensory disturbances, and spreading sensitization and neuroinflammation. Conversely, a facilitatory influence over preganglionic neurons located in IML cell column may increase sympathetic outflow with peripheral vasoconstriction, which leads to cold skin, ipsilateral limb ischaemia, and sympathetically maintained pain (SMP). For patients presenting with these symptoms, a descending inhibitory influence would be predicted to result in decreased sympathetic outflow and warm skin, as well as impairment of peripheral vasoconstrictor reflexes. Finally, a descending inhibitory influence over VH could explain muscle weakness and decreased active range of motion, while also facilitating motor reflexes, tremor and dystonia. The proposed model provides a mechanistically based diagnostic scheme for classifying and explaining the sensory, autonomic and motor disturbances associated with CRPS syndrome. Wiley Periodicals, Inc.

  3. Unicode Explained

    CERN Document Server

    Korpela, Jukka

    2006-01-01

    Fundamentally, computers just deal with numbers. They store letters and other characters by assigning a number for each one. There are hundreds of different encoding systems for mapping characters to numbers, but Unicode promises a single mapping. Unicode enables a single software product or website to be targeted across multiple platforms, languages and countries without re-engineering. It's no wonder that industry giants like Apple, Hewlett-Packard, IBM andMicrosoft have all adopted Unicode. Containing everything you need to understand Unicode, this comprehensive reference from O'Reilly ta

  4. Morphological and physiological responses of different wheat genotypes to chilling stress: a cue to explain yield loss.

    Science.gov (United States)

    Li, Pu-Fang; Ma, Bao-Luo; Xiong, You-Cai; Zhang, Wen-Yuan

    2017-09-01

    The eco-physiological mechanism of wheat yield loss resulting from chilling stress is a fundamental scientific issue. However, previous studies have focused on hexaploid wheats, and few studies on the morphological and physiological plasticity of wheat plants. Six different wheat genotypes were tested under chilling stress to investigate the physio-morphological parameters as well as the loss of grain yield in growth chambers. Chilling stress resulted in significant loss in grain yield in all genotypes. Under chilling stress, diploid wheats generated zero harvest, and tetraploid genotypes also suffered from a pronounced loss in grain yield, compared with the control group. In contrast, hexaploid genotypes acquired relatively high maintenance rate of grain yield among three species. Diploid and tetraploid wheat genotypes maintained relatively large leaf area and high photosynthetic rates, but they were subjected to significant declines in vascular bundle number and productive tillers as a consequence of the inhibition by sink growth under chilling stress. The hexaploid wheats were found to have relatively low leaf area and photosynthetic rates. These genotypes also stored more soluble carbohydrates and exhibited stronger sink enhancement, ensuring the translocation and redistribution of assimilates. Our findings provided a new theoretical understanding of yield stabilization in the domestication process of wheat genotypes under chilling stress. © 2017 Her Majesty the Queen in Right of Canada. Journal of The Science of Food and Agriculture © 2017 Society of Chemical Industry. © 2017 Her Majesty the Queen in Right of Canada. Journal of The Science of Food and Agriculture © 2017 Society of Chemical Industry.

  5. Investigating differences across host species and scales to explain the distribution of the amphibian pathogen Batrachochytrium dendrobatidis.

    Directory of Open Access Journals (Sweden)

    Anna C Peterson

    Full Text Available Many pathogens infect more than one host species, and clarifying how these different hosts contribute to pathogen dynamics can facilitate the management of pathogens and can lend insight into the functioning of pathogens in ecosystems. In this study, we investigated a suite of native and non-native amphibian hosts of the pathogen Batrachochytrium dendrobatidis (Bd across multiple scales to identify potential mechanisms that may drive infection patterns in the Colorado study system. Specifically, we aimed to determine if: 1 amphibian populations vary in Bd infection across the landscape, 2 amphibian community composition predicts infection (e.g., does the presence or abundance of any particular species influence infection in others?, 3 amphibian species vary in their ability to produce infectious zoospores in a laboratory infection, 4 heterogeneity in host ability observed in the laboratory scales to predict patterns of Bd prevalence in the landscape. We found that non-native North American bullfrogs (Lithobates catesbeianus are widespread and have the highest prevalence of Bd infection relative to the other native species in the landscape. Additionally, infection in some native species appears to be related to the density of sympatric L. catesbeianus populations. At the smaller host scale, we found that L. catesbeianus produces more of the infective zoospore stage relative to some native species, but that this zoospore output does not scale to predict infection in sympatric wild populations of native species. Rather, landscape level infection relates most strongly to density of hosts at a wetland as well as abiotic factors. While non-native L. catesbeianus have high levels of Bd infection in the Colorado Front Range system, we also identified Bd infection in a number of native amphibian populations allopatric with L. catesbeianus, suggesting that multiple host species are important contributors to the dynamics of the Bd pathogen in this

  6. Shifts in microbial trophic strategy explain different temperature sensitivity of CO2 flux under constant and diurnally varying temperature regimes.

    Science.gov (United States)

    Bai, Zhen; Xie, Hongtu; Kao-Kniffin, Jenny; Chen, Baodong; Shao, Pengshuai; Liang, Chao

    2017-05-01

    Understanding soil CO2 flux temperature sensitivity (Q10) is critical for predicting ecosystem-level responses to climate change. Yet, the effects of warming on microbial CO2 respiration still remain poorly understood under current Earth system models, partly as a result of thermal acclimation of organic matter decomposition. We conducted a 117-day incubation experiment under constant and diurnally varying temperature treatments based on four forest soils varying in vegetation stand and soil horizon. Our results showed that Q10 was greater under varying than constant temperature regimes. This distinction was most likely attributed to differences in the depletion of available carbon between constant high and varying high-temperature treatments, resulting in significantly higher rates of heterotrophic respiration in the varying high-temperature regime. Based on 16S rRNA gene sequencing data using Illumina, the varying high-temperature regime harbored higher prokaryotic alpha-diversity, was more dominated by the copiotrophic strategists and sustained a distinct community composition, in comparison to the constant-high treatment. We found a tightly coupled relationship between Q10 and microbial trophic guilds: the copiotrophic prokaryotes responded positively with high Q10 values, while the oligotrophs showed a negative response. Effects of vegetation stand and soil horizon consistently supported that the copiotrophic vs oligotrophic strategists determine the thermal sensitivity of CO2 flux. Our observations suggest that incorporating prokaryotic functional traits, such as shifts between copiotrophy and oligotrophy, is fundamental to our understanding of thermal acclimation of microbially mediated soil organic carbon cycling. Inclusion of microbial functional shifts may provide the potential to improve our projections of responses in microbial community and CO2 efflux to a changing environment in forest ecosystems. © FEMS 2017. All rights reserved. For permissions

  7. Can socio-economic differences explain low expectation of health services among HIV patients compared to non-HIV counterparts?

    Science.gov (United States)

    Li, Jing; Assanangkornchai, Sawitri; Lu, Lin; Cai, Le; You, Jing; McNeil, Edward B; Chongsuvivatwong, Virasakdi

    2016-09-09

    The health service of China has encountered significant challenges due to inequalities in socio-economic determinants of health. HIV patients are known to suffer from social stigma, and may receive inadequate responsiveness from health providers. Before assessing the responsiveness they receive, it is important to know their expectations. We aimed to compare levels of expectation towards the healthcare service among HIV and non-HIV patients with adjustment for socio-economic factors. A cross-sectional study was conducted during January and February, 2015 among two consecutive groups of HIV positive and non-HIV patients in two hospitals in Kunming, China. Patients' expectation towards eight domains of health system responsiveness was measured using 40 vignettes; five per domain. Each vignette was ranked from 1 "very good" to 5 "very bad", and the responses were summed to obtain a total score for each domain. Differences in total scores were compared between the two groups and adjusted for other factors using multiple linear regression. The three domains with the highest scores, reflecting high expectation, were prompt attention, basic amenities and choice. Adjusted for other factors, HIV patients had significantly lower levels of expectation in all domains compared to the non-HIV group. Age was associated with the basic amenities domain, with young adults having higher expectations than other age groups. Minority ethnic groups had lower expectation towards dignity, prompt attention and autonomy domains compared to Han ethnicity. Those who lived in a home with 2-4 family members had higher expectations towards confidentiality than those who lived alone. Patients with HIV have significantly lower levels of expectations even after adjusting for socio-economic factors. Assessment of health system responsiveness based on their judgments above may give biased results toward favorable service quality.

  8. Can socio-economic differences explain low expectation of health services among HIV patients compared to non-HIV counterparts?

    Directory of Open Access Journals (Sweden)

    Jing Li

    2016-09-01

    Full Text Available Abstract Background The health service of China has encountered significant challenges due to inequalities in socio-economic determinants of health. HIV patients are known to suffer from social stigma, and may receive inadequate responsiveness from health providers. Before assessing the responsiveness they receive, it is important to know their expectations. We aimed to compare levels of expectation towards the healthcare service among HIV and non-HIV patients with adjustment for socio-economic factors. Methods A cross-sectional study was conducted during January and February, 2015 among two consecutive groups of HIV positive and non-HIV patients in two hospitals in Kunming, China. Patients’ expectation towards eight domains of health system responsiveness was measured using 40 vignettes; five per domain. Each vignette was ranked from 1 “very good” to 5 “very bad”, and the responses were summed to obtain a total score for each domain. Differences in total scores were compared between the two groups and adjusted for other factors using multiple linear regression. Results The three domains with the highest scores, reflecting high expectation, were prompt attention, basic amenities and choice. Adjusted for other factors, HIV patients had significantly lower levels of expectation in all domains compared to the non-HIV group. Age was associated with the basic amenities domain, with young adults having higher expectations than other age groups. Minority ethnic groups had lower expectation towards dignity, prompt attention and autonomy domains compared to Han ethnicity. Those who lived in a home with 2–4 family members had higher expectations towards confidentiality than those who lived alone. Conclusion Patients with HIV have significantly lower levels of expectations even after adjusting for socio-economic factors. Assessment of health system responsiveness based on their judgments above may give biased results toward favorable service

  9. Canceled connections: Lesion-derived network mapping helps explain differences in performance on a complex decision-making task

    Science.gov (United States)

    Sutterer, Matthew J.; Bruss, Joel; Boes, Aaron D.; Voss, Michelle W.; Bechara, Antoine; Tranel, Daniel

    2016-01-01

    Studies of patients with brain damage have highlighted a broad neural network of limbic and prefrontal areas as important for adaptive decision-making. However, some patients with damage outside these regions have impaired decision-making behavior, and the behavioral impairments observed in these cases are often attributed to the general variability in behavior following brain damage, rather than a deficit in a specific brain-behavior relationship. A novel approach, lesion-derived network mapping, uses healthy subject resting-state functional connectivity (RSFC) data to infer the areas that would be connected with each patient’s lesion area in healthy adults. Here, we used this approach to investigate whether there was a systematic pattern of connectivity associated with decision-making performance in patients with focal damage in areas not classically associated with decision-making. These patients were categorized a priori into “impaired” or “unimpaired” groups based on their performance on the Iowa Gambling Task (IGT). Lesion-derived network maps based on the impaired patients showed overlap in somatosensory, motor and insula cortices, to a greater extent than patients who showed unimpaired IGT performance. Akin to the classic concept of “diaschisis” (von Monakow, 1914), this focus on the remote effects that focal damage can have on large-scale distributed brain networks has the potential to inform not only differences in decision-making behavior, but also other cognitive functions or neurological syndromes where a distinct phenotype has eluded neuroanatomical classification and brain-behavior relationships appear highly heterogeneous. PMID:26994344

  10. Quality of Life and Functional Status Across the Life Course. Project 2: Investigating Mechanisms to Explain Age Associated Differences in Quality of Life Among Breast Cancer Patients

    Science.gov (United States)

    2002-10-01

    cancer at a young age. 4.3.4 Reproductive History Participants will be asked questions about their age of menarche, past pregnancies and buths...LINE.) Does Not Apply No Yes Don’t know if she had breast cancer How old breas WM she when her first it cancer occurred? 3. Did this...Explain Age Associated Differences in Quality of Life Among Breast Cancer Patients PRINCIPAL INVESTIGATOR: Michelle J. Naughton, Ph.D. Nancy E

  11. Will I Fit in and Do Well? The Importance of Social Belongingness and Self-Efficacy for Explaining Gender Differences in Interest in STEM and HEED Majors.

    Science.gov (United States)

    Tellhed, Una; Bäckström, Martin; Björklund, Fredrik

    2017-01-01

    Throughout the world, the labor market is clearly gender segregated. More research is needed to explain women's lower interest in STEM (Science, Technology, Engineering and Mathematics) majors and particularly to explain men's lower interest in HEED (Health care, Elementary Education, and the Domestic spheres) majors. We tested self-efficacy (competence beliefs) and social belongingness expectations (fitting in socially) as mediators of gender differences in interest in STEM and HEED majors in a representative sample of 1327 Swedish high school students. Gender differences in interest in STEM majors strongly related to women's lower self-efficacy for STEM careers and, to a lesser degree, to women's lower social belongingness expectations with students in STEM majors. Social belongingness expectations also partly explained men's lower interest in HEED majors, but self-efficacy was not an important mediator of gender differences in interest in HEED. These results imply that interventions designed to lessen gender segregation in the labor market need to focus more on the social belongingness of students in the gender minority. Further, to specifically increase women's interest in STEM majors, we need to counteract gender stereotypical competence beliefs and assure women that they have what it takes to handle STEM careers.

  12. Target product selection - where can Molecular Pharming make the difference?

    Science.gov (United States)

    Paul, Mathew J; Teh, Audrey Y H; Twyman, Richard M; Ma, Julian K-C

    2013-01-01

    Four major developments have taken place in the world of Molecular Pharming recently. In the USA, the DARPA initiative challenged plant biotechnology companies to develop strategies for the large-scale manufacture of influenza vaccines, resulting in a successful Phase I clinical trial; in Europe the Pharma-Planta academic consortium gained regulatory approval for a plant-derived monoclonal antibody and completed a first-in-human phase I clinical trial; the Dutch pharmaceutical company Synthon acquired the assets of Biolex Therapeutics, an established Molecular Pharming company with several clinical candidates produced in their proprietary LEX system based on aquatic plants; and finally, the Israeli biotechnology company Protalix Biotherapeutics won FDA approval for the commercial release of a recombinant form of the enzyme glucocerebrosidase produced in carrot cells, the first plant biotechnology-derived biopharmaceutical in the world approved for the market. Commercial momentum is gathering pace with additional candidates now undergoing or awaiting approval for phase III clinical trials. Filling the product pipeline is vital to establish commercial sustainability, and the selection of appropriate target products for Molecular Pharming will be a critical factor. An interesting feature of the four stories outlined above is that they span the use of very different platform technologies addressing different types of molecules which aim to satisfy distinct market demands. In each case, Molecular Pharming was an economically and technically suitable approach, but this decisionmaking process is not necessarily straightforward. Although the various technologies available to Molecular Pharming are broad ranging and flexible, competing technologies are better established, so there needs to be a compelling reason to move into plants. It is most unlikely that plant biotechnology will be the answer for the whole biologics field. In this article, we discuss the current plant

  13. The strong selective sweep candidate gene ADRA2C does not explain domestication related changes in the stress response of chickens.

    Directory of Open Access Journals (Sweden)

    Magnus Elfwing

    Full Text Available Analysis of selective sweeps to pinpoint causative genomic regions involved in chicken domestication has revealed a strong selective sweep on chromosome 4 in layer chickens. The autoregulatory α-adrenergic receptor 2C (ADRA2C gene is the closest to the selective sweep and was proposed as an important gene in the domestication of layer chickens. The ADRA2C promoter region was also hypermethylated in comparison to the non-selected ancestor of all domesticated chicken breeds, the Red Junglefowl, further supporting its relevance. In mice the receptor is involved in the fight-or-flight response as it modulates epinephrine release from the adrenals. To investigate the involvement of ADRA2C in chicken domestication, we measured gene expression in the adrenals and radiolabeled receptor ligand in three brain regions comparing the domestic White Leghorn strain with the wild ancestor Red Junglefowl. In adrenals ADRA2C was twofold greater expressed than the related receptor gene ADRA2A, indicating that ADRA2C is the predominant modulator of epinephrine release but no strain differences were measured. In hypothalamus and amygdala, regions associated with the stress response, and in striatum, receptor binding pIC50 values ranged between 8.1-8.4, and the level was not influenced by the genotyped allele. Because chicken strains differ in morphology, physiology and behavior, differences attributed to a single gene may be lost in the noise caused by the heterogeneous genetic background. Therefore an F10 advanced intercross strain between White Leghorn and Red Junglefowl was used to investigate effects of ADRA2C alleles on fear related behaviors and fecundity. We did not find compelling genotype effects in open field, tonic immobility, aerial predator, associative learning or fecundity. Therefore we conclude that ADRA2C is probably not involved in the domestication of the stress response in chicken, and the strong selective sweep is probably caused by selection

  14. The relative importance of socioeconomic indicators in explaining differences in BMI and waist:hip ratio, and the mediating effect of work control, dietary patterns and physical activity.

    Science.gov (United States)

    Kjøllesdal, Marte Råberg; Holmboe-Ottesen, Gerd; Mosdøl, Annhild; Wandel, Margareta

    2010-10-01

    Socioeconomic differences in overweight are well documented, but most studies have only used one or two indicators of socioeconomic position (SEP). The aim of the present study was to explore the relative importance of indicators of SEP (occupation, education and income) in explaining variation in BMI and waist:hip ratio (WHR), and the mediating effect of work control and lifestyle factors (dietary patterns, smoking and physical activity). The Oslo Health Study, a cross-sectional study, was carried out in 2000-1, Oslo, Norway. Our sample included 9235 adult working Oslo citizens, who attended a health examination and filled in two complementary FFQ with < 20% missing responses to food items. Four dietary patterns were identified through factor analysis, and were named 'modern', 'Western', 'traditional' and 'sweet'. In multivariate models, BMI and WHR were inversely associated with education (P < 0.001/P < 0.001) and occupation (P = 0.002/P < 0.001), whereas there were no significant associations with income or the work control. The 'modern' (P < 0.001) and the 'sweet' (P < 0.001) dietary patterns and physical activity level (P < 0.001) were inversely associated, while the 'Western' dietary pattern (P < 0.001) was positively associated with both BMI and WHR. These lifestyle factors could not fully explain the socioeconomic differences in BMI or WHR. However, together with socioeconomic factors, they explained more of the variation in WHR among men (21%) than among women (7%).

  15. Differences in selection drive olfactory receptor genes in different directions in dogs and wolf.

    Science.gov (United States)

    Chen, Rui; Irwin, David M; Zhang, Ya-Ping

    2012-11-01

    The olfactory receptor (OR) gene family is the largest gene family found in mammalian genomes. It is known to evolve through a birth-and-death process. Here, we characterized the sequences of 16 segregating OR pseudogenes in the samples of the wolf and the Chinese village dog (CVD) and compared them with the sequences from dogs of different breeds. Our results show that the segregating OR pseudogenes in breed dogs are under strong purifying selection, while evolving neutrally in the CVD, and show a more complicated pattern in the wolf. In the wolf, we found a trend to remove deleterious polymorphisms and accumulate nondeleterious polymorphisms. On the basis of protein structure of the ORs, we found that the distribution of different types of polymorphisms (synonymous, nonsynonymous, tolerated, and untolerated) varied greatly between the wolf and the breed dogs. In summary, our results suggest that different forms of selection have acted on the segregating OR pseudogenes in the CVD since domestication, breed dogs after breed formation, and ancestral wolf population, which has driven the evolution of these genes in different directions.

  16. A mathematical epidemiological model of gram-negative Bartonella bacteria: does differential ectoparasite load fully explain the differences in infection prevalence of Rattus rattus and Rattus norvegicus?

    Science.gov (United States)

    Brettschneider, H; Anguelov, R; Chimimba, C T; Bastos, A D S

    2012-01-01

    We postulate that the large difference in infection prevalence, 24% versus 5%, in R. norvegicus and R. rattus, respectively, between these two co-occurring host species may be due to differences in ectoparasite and potential vector infestation rates. A compartmental model, representative of an infectious system containing these two Rattus species and two ectoparasite vectors, was constructed and the coefficients of the forces of infection determined mathematically. The maximum difference obtained by the model in the prevalence of Bartonella in the two Rattus species amounts to 4.6%, compared to the observed mean difference of 19%. Results suggest the observed higher Bartonella infection prevalence in Rattus norvegicus compared to Rattus rattus, cannot be explained solely by higher ectoparasite load. The model also highlights the need for more detailed biological research on Bartonella infections in Rattus and the importance of the flea vector in the spread of this disease.

  17. Differences in minor amputation rate in diabetic foot disease throughout Europe are in part explained by differences in disease severity at presentation

    DEFF Research Database (Denmark)

    van Battum, P; Schaper, N; Prompers, L

    2011-01-01

    The incidence of minor amputation may vary significantly, and determinants of minor amputation have not been studied systematically. We evaluated minor amputation rate, the determinants of minor amputation and differences in amputation rate between European centres....

  18. Color selection and location selection in ERPs : differences, similarities and 'neural specificity'

    NARCIS (Netherlands)

    Lange, J.J.; Wijers, A.A.; Mulder, L.J.M.; Mulder, G.

    It was hypothesized that color selection consists of two stages. The first stage represents a feature specific selection in neural populations specialized in processing color. The second stage constitutes feature non-specific selections, related to executive attentional processes and/or motor

  19. The Digital Divide and Patient Portals: Internet Access Explained Differences in Patient Portal Use for Secure Messaging by Age, Race, and Income.

    Science.gov (United States)

    Graetz, Ilana; Gordon, Nancy; Fung, Vick; Hamity, Courtnee; Reed, Mary E

    2016-08-01

    Online access to health records and the ability to exchange secure messages with physicians can improve patient engagement and outcomes; however, the digital divide could limit access to web-based portals among disadvantaged groups. To understand whether sociodemographic differences in patient portal use for secure messaging can be explained by differences in internet access and care preferences. Cross-sectional survey to examine the association between patient sociodemographic characteristics and internet access and care preferences; then, the association between sociodemographic characteristics and secure message use with and without adjusting for internet access and care preference. One thousand forty-one patients with chronic conditions in a large integrated health care delivery system (76% response rate). Internet access, portal use for secure messaging, preference for in-person or online care, and sociodemographic and health characteristics. Internet access and preference mediated some of the differences in secure message use by age, race, and income. For example, using own computer to access the internet explained 52% of the association between race and secure message use and 60% of the association between income and use (Sobel-Goodman mediation test, Pinternet access and preference. As the availability and use of patient portals increase, it is important to understand which patients have limited access and the barriers they may face. Improving internet access and making portals available across multiple platforms, including mobile, may reduce some disparities in secure message use.

  20. Can Ethnic Background Differences in Children's Body Composition Be Explained by Differences in Energy Balance-Related Behaviors? A Mediation Analysis within the Energy-Project

    NARCIS (Netherlands)

    Fernandez Alvira, J.M.; te Velde, S.J.; Jimenez-Pavon, D.; Manios, Y.; Singh, A.S.; Moreno, L.A.; Brug, J.

    2013-01-01

    Background:In affluent countries, children from non-native ethnicity have in general less favourable body composition indicators and energy balance-related behaviors (EBRBs) than children from native ethnicity. However, differences between countries have been reported.Methodology/Principal

  1. Can ethnic background differences in children's body composition be explained by differences in energy balance-related behaviors? A mediation analysis within the energy-project.

    Directory of Open Access Journals (Sweden)

    Juan Miguel Fernández-Alvira

    Full Text Available BACKGROUND: In affluent countries, children from non-native ethnicity have in general less favourable body composition indicators and energy balance-related behaviors (EBRBs than children from native ethnicity. However, differences between countries have been reported. METHODOLOGY/PRINCIPAL FINDINGS: A school-based survey among 10-12 years old children was conducted in seven European countries with a standardized protocol. Weight, height and waist circumference were measured; engagement in EBRBs was self-reported. For those countries with significant ethnic differences in body composition (Greece and the Netherlands, multilevel mediation analyses were conducted, to test the mediating effect of the EBRBs in the association between ethnic background and body composition indicators. Analyses were adjusted for gender and age, and for parental education in a later step. Partial mediation was found for sugared drinks intake and sleep duration in the Greek sample, and breakfast in the Dutch sample. A suppression effect was found for engagement in sports activites in the Greek sample. CONCLUSIONS/SIGNIFICANCE: Ethnic differences in children's body composition were partially mediated by differences in breakfast skipping in the Netherlands and sugared drinks intake, sports participation and sleep duration in Greece.

  2. Regional differences of physical activity and sedentary behaviour in Swiss children are not explained by socio-demographics or the built environment.

    Science.gov (United States)

    Bringolf-Isler, Bettina; Mäder, Urs; Dössegger, Alain; Hofmann, Heidi; Puder, Jardena J; Braun-Fahrländer, Charlotte; Kriemler, Susi

    2015-03-01

    We evaluated whether regional differences in physical activity (PA) and sedentary behaviour (SB) existed along language boundaries within Switzerland and whether potential differences would be explained by socio-demographics or environmental characteristics. We combined data of 611 children aged 4 to 7 years from four regional studies. PA and SB were assessed by accelerometers. Information about the socio-demographic background was obtained by questionnaires. Objective neighbourhood attributes could be linked to home addresses. Multivariate regression models were used to test associations between PA and SB and socio-demographic characteristics and neighbourhood attributes. Children from the German compared to the French-speaking region were more physically active and less sedentary (by 10-15 %, p children lived in a more favourable environment and a higher socioeconomic neighbourhood (differences p children, independent of individual, social and environmental factors.

  3. Non-Selective Lexical Access in Different-Script Bilinguals

    Science.gov (United States)

    Moon, Jihye; Jiang, Nan

    2012-01-01

    Lexical access in bilinguals is known to be largely non-selective. However, most studies in this area have involved bilinguals whose two languages share the same script. This study aimed to examine bilingual lexical access among bilinguals whose two languages have distinct scripts. Korean-English bilinguals were tested in a phoneme monitoring task…

  4. Comparative effects of different walking aids on selected ...

    African Journals Online (AJOL)

    Objective: This study aims at comparing the effects of cane, Rollator, and Zimmer's frame ambulations on selected cardiovascular parameters, energy cost and walking speed in elderly patients with knee osteoarthritis (OA). Method: Twenty-five (25) elderly patients participated in this randomized cross-over designed study.

  5. A Performance of Individual Differences in Selective Attention.

    Science.gov (United States)

    Wahl, Otto

    A reliable, easily administered performance test of selective attentional ability was sought. A monaural listening task provided a baseline control for adequate hearing and memory; a dichotic listening task then provided indices of ability to focus attention and resist distraction while a simultaneous listening task provided measures of ability to…

  6. Using Different Examples of Natural Selection When Teaching Biology.

    Science.gov (United States)

    Perry, Robert T.

    1993-01-01

    Describes the following examples of natural selection for use in science instruction: sickle-cell anemia and human beings, clogged crabs, the rounding of the human head, shell color in land snails, pollinator behavior and flower color, copper tolerance in a grass, lizards and quick change, and Darwin's finches. (PR)

  7. Can gender difference in prescription drug use be explained by gender-related morbidity?: a study on a Swedish population during 2006.

    Science.gov (United States)

    Skoog, Jessica; Midlöv, Patrik; Borgquist, Lars; Sundquist, Jan; Halling, Anders

    2014-04-08

    It has been reported that there is a difference in drug prescription between males and females. Even after adjustment for multi-morbidity, females tend to use more prescription drugs compared to males. In this study, we wanted to analyse whether the gender difference in drug treatment could be explained by gender-related morbidity. Data was collected on all individuals 20 years and older in the county of Östergötland in Sweden. The Johns Hopkins ACG Case-Mix System was used to calculate individual level of multi-morbidity. A report from the Swedish National Institute of Public Health using the WHO term DALY was the basis for gender-related morbidity. Prescription drugs used to treat diseases that mainly affect females were excluded from the analyses. The odds of having prescription drugs for males, compared to females, increased from 0.45 (95% confidence interval (CI) 0.44-0.46) to 0.82 (95% CI 0.81-0.83) after exclusion of prescription drugs that are used to treat diseases that mainly affect females. Gender-related morbidity and the use of anti-conception drugs may explain a large part of the difference in prescription drug use between males and females but still there remains a difference between the genders at 18%. This implicates that it is of importance to take the gender-related morbidity into consideration, and to exclude anti-conception drugs, when performing studies regarding difference in drug use between the genders.

  8. Study of different factors which can explain the radon exhalation potential of soils; Recherche de differents parametres caracterisant le potentiel d`exhalation en radon des sols

    Energy Technology Data Exchange (ETDEWEB)

    Demongeot, St

    1997-10-27

    Radon is a natural radioactive gas belonging to the Uranium-238 chain, which is present in the earth crust and produced by the disintegration of radium-226. It is considered as the major source of radiological exposure of man to natural radiation because it can accumulate in indoor atmosphere. So, this health risk must be take into account.The aim of this study is to find some tools in order to identify high radon level area. The first part of this study has consisted in measurement of radon emission from different not sufficient for the estimation of the radon exhalation potential in a given area. In the second part of this work, we have studied the variations of in situ radon concentration as a function of different geological and pedologic parameters of the site. With the results obtained, we have determined the data which have to be considered, and the methodology to be applied for the determination of the radon exhalation of a given area. Furthermore, by the mean of numerical simulations (TRACH Model), it was possible to know the scale of radon flux variation in a given point versus the hydric state of the ground and thus the permeability: these parameters are not easy to measure because of their variabilities with time. The methodology ESPERAS (EStimation du Potential d`Exhalation en Radon des Sols) developed during this work was applied first, at a local scale and then to greater area. The values estimated by this way are in a good agreement with the results of measurements. So, we can determine the areas which are affected by high radon levels. (author)

  9. Genomic selection: Status in different species and challenges for breeding.

    Science.gov (United States)

    Stock, K F; Reents, R

    2013-09-01

    Technical advances and development in the market for genomic tools have facilitated access to whole-genome data across species. Building-up on the acquired knowledge of the genome sequences, large-scale genotyping has been optimized for broad use, so genotype information can be routinely used to predict genetic merit. Genomic selection (GS) refers to the use of aggregates of estimated marker effects as predictors which allow improved individual differentiation at young age. Realizable benefits of GS are influenced by several factors and vary in quantity and quality between species. General characteristics and challenges of GS in implementation and routine application are described, followed by an overview over the current status of its use, prospects and challenges in important animal species. Genetic gain for a particular trait can be enhanced by shortening of the generation interval, increased selection accuracy and increased selection intensity, with species- and breed-specific relevance of the determinants. Reliable predictions based on genetic marker effects require assembly of a reference for linking of phenotype and genotype data to allow estimation and regular re-estimation. Experiences from dairy breeding have shown that international collaboration can set the course for fast and successful implementation of innovative selection tools, so genomics may significantly impact the structures of future breeding and breeding programmes. Traits of great and increasing importance, which were difficult to improve in the conventional systems, could be emphasized, if continuous availability of high-quality phenotype data can be assured. Equally elaborate strategies for genotyping and phenotyping will allow tailored approaches to balance efficient animal production, sustainability, animal health and welfare in future. © 2013 Blackwell Verlag GmbH.

  10. Variation in mutation spectrum partly explains regional differences in the breast cancer risk of female BRCA mutation carriers in the Netherlands.

    Science.gov (United States)

    Vos, Janet R; Teixeira, Natalia; van der Kolk, Dorina M; Mourits, Marian J E; Rookus, Matti A; van Leeuwen, Flora E; Collée, Margriet; van Asperen, Christi J; Mensenkamp, Arjen R; Ausems, Margreet G E M; van Os, Theo A M; Meijers-Heijboer, Hanne E J; Gómez-Garcia, Encarna B; Vasen, Hans F; Brohet, Richard M; van der Hout, Annemarie H; Jansen, Liesbeth; Oosterwijk, Jan C; de Bock, Geertruida H

    2014-11-01

    We aimed to quantify previously observed relatively high cancer risks in BRCA2 mutation carriers (BRCA2 carriers) older than 60 in the Northern Netherlands, and to analyze whether these could be explained by mutation spectrum or population background risk. This consecutive cohort study included all known pathogenic BRCA1/2 carriers in the Northern Netherlands (N = 1,050). Carrier and general reference populations were: BRCA1/2 carriers in the rest of the Netherlands (N = 2,013) and the general population in both regions. Regional differences were assessed with HRs and ORs. HRs were adjusted for birth year and mutation spectrum. All BRCA1 carriers and BRCA2 carriers younger than 60 had a significantly lower breast cancer risk in the Northern Netherlands; HRs were 0.66 and 0.64, respectively. Above age 60, the breast cancer risk in BRCA2 carriers in the Northern Netherlands was higher than in the rest of the Netherlands [HR, 3.99; 95% confidence interval (CI), 1.11-14.35]. Adjustment for mutational spectrum changed the HRs for BRCA1, BRCA2 <60, and BRCA2 ≥60 years by -3%, +32%, and +11% to 0.75, 0.50, and 2.61, respectively. There was no difference in background breast cancer incidence between the two regions (OR, 1.03; 95% CI, 0.97-1.09). Differences in mutation spectrum only partly explain the regional differences in breast cancer risk in BRCA2 carriers, and for an even smaller part in BRCA1 carriers. The increased risk in BRCA2 carriers older than 60 may warrant extension of intensive breast screening beyond age 60. ©2014 American Association for Cancer Research.

  11. Metabolite Profiling of Barley Grains Subjected to Water Stress: To Explain the Genotypic Difference in Drought-Induced Impacts on Malting Quality

    Directory of Open Access Journals (Sweden)

    Xiaojian Wu

    2017-09-01

    Full Text Available Grain weight and protein content will be reduced and increased, respectively, when barley is subjected to water stress after anthesis, consequently deteriorating the malt quality. However, such adverse impact of water stress differs greatly among barley genotypes. In this study, two Tibetan wild barley accessions and two cultivated varieties differing in water stress tolerance were used to investigate the genotypic difference in metabolic profiles during grain-filling stage under drought condition. Totally, 71 differently accumulated metabolites were identified, including organic acids, amino acids/amines, and sugars/sugar alcohols. Their relative contents were significantly affected by water stress for all genotypes and differed distinctly between the wild and cultivated barleys. The principal component analysis of metabolites indicated that the Tibetan wild barley XZ147 possessed a unique response to water stress. When subjected to water stress, the wild barley XZ147 showed the most increase of β-amylase activity among the four genotypes, as a result of its higher lysine content, less indole-3-acetic acid (IAA biosynthesis, more stable H2O2 homeostasis, and more up-regulation of BMY1 gene. On the other hand, XZ147 had the most reduction of β-glucan content under water stress than the other genotypes, which could be explained by the faster grain filling process and the less expression of β-glucan synthase gene GSL7. All these results indicated a great potential for XZ147 in barley breeding for improving water stress tolerance.

  12. Structures of the Porphyromonas gingivalis OxyR regulatory domain explain differences in expression of the OxyR regulon in Escherichia coli and P. gingivalis

    Energy Technology Data Exchange (ETDEWEB)

    Svintradze, David V. [Virginia Commonwealth University, Richmond, VA 23298-0566 (United States); Virginia Commonwealth University, Richmond, VA 23219-1540 (United States); Peterson, Darrell L. [Virginia Commonwealth University, Richmond, VA 23219-1540 (United States); Virginia Commonwealth University, Richmond, VA 23298-0614 (United States); Collazo-Santiago, Evys A.; Lewis, Janina P. [Virginia Commonwealth University, Richmond, VA 23298-0566 (United States); Wright, H. Tonie, E-mail: xrdproc@vcu.edu [Virginia Commonwealth University, Richmond, VA 23219-1540 (United States); Virginia Commonwealth University, Richmond, VA 23298-0614 (United States); Virginia Commonwealth University, Richmond, VA 23298-0566 (United States)

    2013-10-01

    Differences in OxyR regulated expression of oxidative stress genes between Escherichia coli and Porphyromonas gingivalis are explained by very minor differences in structure and amino-acid sequence of the respective oxidized and reduced OxyR regulatory domains. These differences affect OxyR quaternary structures and are predicted from model building of full length OxyR–DNA complexes to confer distinct modes of DNA binding on this transcriptional regulator. OxyR transcriptionally regulates Escherichia coli oxidative stress response genes through a reversibly reducible cysteine disulfide biosensor of cellular redox status. Structural changes induced by redox changes in these cysteines are conformationally transmitted to the dimer subunit interfaces, which alters dimer and tetramer interactions with DNA. In contrast to E. coli OxyR regulatory-domain structures, crystal structures of Porphyromonas gingivalis OxyR regulatory domains show minimal differences in dimer configuration on changes in cysteine disulfide redox status. This locked configuration of the P. gingivalis OxyR regulatory-domain dimer closely resembles the oxidized (activating) form of the E. coli OxyR regulatory-domain dimer. It correlates with the observed constitutive activation of some oxidative stress genes in P. gingivalis and is attributable to a single amino-acid insertion in P. gingivalis OxyR relative to E. coli OxyR. Modelling of full-length P. gingivalis, E. coli and Neisseria meningitidis OxyR–DNA complexes predicts different modes of DNA binding for the reduced and oxidized forms of each.

  13. The wireless internet explained

    CERN Document Server

    Rhoton, John

    2001-01-01

    The Wireless Internet Explained covers the full spectrum of wireless technologies from a wide range of vendors, including initiatives by Microsoft and Compaq. The Wireless Internet Explained takes a practical look at wireless technology. Rhoton explains the concepts behind the physics, and provides an overview that clarifies the convoluted set of standards heaped together under the umbrella of wireless. It then expands on these technical foundations to give a panorama of the increasingly crowded landscape of wireless product offerings. When it comes to actual implementation the book gives abundant down-to-earth advice on topics ranging from the selection and deployment of mobile devices to the extremely sensitive subject of security.Written by an expert on Internet messaging, the author of Digital Press''s successful Programmer''s Guide to Internet Mail and X.400 and SMTP: Battle of the E-mail Protocols, The Wireless Internet Explained describes and evaluates the current state of the fast-growing and crucial...

  14. Can labour contract differences in health and work-related attitudes be explained by quality of working life and job insecurity?

    Science.gov (United States)

    Wagenaar, Alfred F; Kompier, Michiel A J; Houtman, Irene L D; van den Bossche, Seth; Smulders, Peter; Taris, Toon W

    2012-10-01

    We hypothesise that due to a lower quality of working life and higher job insecurity, the health and work-related attitudes of temporary workers may be less positive compared to permanent workers. Therefore, we aimed to (1) examine differences between contract groups (i.e. permanent contract, temporary contract with prospect of permanent work, fixed-term contract, temporary agency contract and on-call contract) in the quality of working life, job insecurity, health and work-related attitudes and (2) investigate whether these latter contract group differences in health and work-related attitudes can be explained by differences in the quality of working life and/or job insecurity. Data were collected from the Netherlands Working Conditions Survey 2008 (N = 21,639), and Hypotheses were tested using analysis of variance and cross-table analysis. Temporary work was associated with fewer task demands and lower autonomy and was more often passive or high-strain work, while permanent work was more often active work. Except for on-call work, temporary work was more insecure and associated with worse health and work-related attitude scores than permanent work. Finally, the quality of working life and job insecurity partly accounted for most contract differences in work-related attitudes but not in health. Especially agency workers have a lower health status and worse work-related attitudes. Job redesign measures regarding their quality of working life and job insecurity are recommended.

  15. Explaining racial/ethnic differences in all-cause mortality in the Multi-Ethnic Study of Atherosclerosis (MESA: Substantive complexity and hazardous working conditions as mediating factors

    Directory of Open Access Journals (Sweden)

    Kaori Fujishiro

    2017-12-01

    Full Text Available Research on racial/ethnic health disparities and socioeconomic position has not fully considered occupation. However, because occupations are racially patterned, certain occupational characteristics may explain racial/ethnic difference in health. This study examines the role of occupational characteristics in racial/ethnic disparities in all-cause mortality. Data are from a U.S. community-based cohort study (n=6342, median follow-up: 12.2 years, in which 893 deaths (14.1% occurred. We estimated mortality hazard ratios (HRs for African Americans, Hispanics, and Chinese Americans compared with whites. We also estimated the proportion of the HR mediated by each of two occupational characteristics, substantive complexity of work (e.g., problem solving, inductive/deductive reasoning on the job and hazardous conditions (e.g., noise, extreme temperature, chemicals, derived from the Occupational Information Network database (O*NET. Analyses were adjusted for age, sex, nativity, working status at baseline, and study sites. African Americans had a higher rate of all-cause death (HR 1.41; 95% confidence interval [CI]: 1.19–1.66 than whites. Chinese-American ethnicity was protective (HR 0.59, CI: 0.40–0.85; Hispanic ethnicity was not significantly different from whites (HR 0.88; CI: 0.67–1.17. Substantive complexity of work mediated 30% of the higher rate of death for African Americans compared with whites. For other groups, mediation was not significant. Hazardous conditions did not significantly mediate mortality in any racial/ethnic group. Lower levels of substantive complexity of work mediate a substantial part of the health disadvantage in African Americans. This job characteristic may be an important factor in explaining racial health disparities.

  16. Mate selection preferences: gender differences examined in a national sample.

    Science.gov (United States)

    Sprecher, S; Sullivan, Q; Hatfield, E

    1994-06-01

    Social psychologists have devoted considerable theoretical and empirical attention to studying gender differences in traits desired in a mate. Most of the studies on mate preferences, however, have been conducted with small, nonrepresentative samples. In this study, we analyzed data collected from single adults in a national probability sample, the National Survey of Families and Households. Respondents were asked to consider 12 possible assets or liabilities in a marriage partner and to indicate their willingness to marry someone possessing each of these traits. These data extended previous research by comparing men's and women's mate preferences in a heterogeneous sample of the national population and by comparing gender differences in different sociodemographic groups. The gender differences found in this study were consistent with those secured in previous research (e.g., youth and physical attractiveness were found to be more important for men than for women; earning potential was found to be less important for men than for women) and were quite consistent across age groups and races. However, the various sociodemographic groups differed slightly in the magnitude of gender differences for some of the mate preferences.

  17. Explaining the gender wealth gap.

    Science.gov (United States)

    Ruel, Erin; Hauser, Robert M

    2013-08-01

    To assess and explain the United States' gender wealth gap, we use the Wisconsin Longitudinal Study to examine wealth accumulated by a single cohort over 50 years by gender, by marital status, and limited to the respondents who are their family's best financial reporters. We find large gender wealth gaps between currently married men and women, and between never-married men and women. The never-married accumulate less wealth than the currently married, and there is a marital disruption cost to wealth accumulation. The status-attainment model shows the most power in explaining gender wealth gaps between these groups explaining about one-third to one-half of the gap, followed by the human-capital explanation. In other words, a lifetime of lower earnings for women translates into greatly reduced wealth accumulation. After controlling for the full model, we find that a gender wealth gap remains between married men and women that we speculate may be related to gender differences in investment strategies and selection effects.

  18. Personality Differences Among Men In Selected Air Force Specialties

    Science.gov (United States)

    Wigington, John H.; Apostal, Robert A.

    1973-01-01

    The results of the analyses of variance indicate that differences exist among the examined Air Force specialties on four VPI scales; realistic intellectual self-control, and status. These results might be considered by school, college, and military counselors in their vocational counseling of prospective and enlisted airmen. (Author)

  19. Effects of adding aluminum sulfate to different litters on selected ...

    African Journals Online (AJOL)

    The objective of this study was to determine the effects of adding aluminum sulfate to different litters on blood plasma concentrations of some principal microelements and some vitamins in broilers. In this experiment, 645 day old Ross 308 broiler chicks were randomly divided into 4 litter group (straw, sawdust, alum ...

  20. Human Performance: Psychological and Physiological Sex Differences (A Selected Bibliography)

    Science.gov (United States)

    1980-02-01

    Psychology of Women, 1977, _2, 187-190. 16. Wlrtenberg, J. Review of Humanness: An exploration into the mythologies about women and men edited by...aggression shows sex differences (Summary of paper presented by R. P. Rohner at the Easter Psychological Association Meeting, 1976). Behavior Today

  1. What explains rare and conspicuous colours in a snail? A test of time-series data against models of drift, migration or selection.

    Science.gov (United States)

    Johannesson, K; Butlin, R K

    2017-01-01

    It is intriguing that conspicuous colour morphs of a prey species may be maintained at low frequencies alongside cryptic morphs. Negative frequency-dependent selection by predators using search images ('apostatic selection') is often suggested without rejecting alternative explanations. Using a maximum likelihood approach we fitted predictions from models of genetic drift, migration, constant selection, heterozygote advantage or negative frequency-dependent selection to time-series data of colour frequencies in isolated populations of a marine snail (Littorina saxatilis), re-established with perturbed colour morph frequencies and followed for >20 generations. Snails of conspicuous colours (white, red, banded) are naturally rare in the study area (usually Directional selection was rejected in three populations in favour of balancing selection. Heterozygote advantage and negative frequency-dependent selection could not be distinguished statistically, although overall the results favoured the latter. Populations varied idiosyncratically as mild or variable colour selection (3-11%) interacted with demographic stochasticity, and the overall conclusion was that multiple mechanisms may contribute to maintaining the polymorphisms.

  2. Cuttability Assessment of Selected Rocks Through Different Brittleness Values

    Science.gov (United States)

    Dursun, Arif Emre; Gokay, M. Kemal

    2016-04-01

    Prediction of cuttability is a critical issue for successful execution of tunnel or mining excavation projects. Rock cuttability is also used to determine specific energy, which is defined as the work done by the cutting force to excavate a unit volume of yield. Specific energy is a meaningful inverse measure of cutting efficiency, since it simply states how much energy must be expended to excavate a unit volume of rock. Brittleness is a fundamental rock property and applied in drilling and rock excavation. Brittleness is one of the most crucial rock features for rock excavation. For this reason, determination of relations between cuttability and brittleness will help rock engineers. This study aims to estimate the specific energy from different brittleness values of rocks by means of simple and multiple regression analyses. In this study, rock cutting, rock property, and brittleness index tests were carried out on 24 different rock samples with different strength values, including marble, travertine, and tuff, collected from sites around Konya Province, Turkey. Four previously used brittleness concepts were evaluated in this study, denoted as B 1 (ratio of compressive to tensile strength), B 2 (ratio of the difference between compressive and tensile strength to the sum of compressive and tensile strength), B 3 (area under the stress-strain line in relation to compressive and tensile strength), and B 9 = S 20, the percentage of fines (Brazilian tensile, and point load strengths of rocks using multiple regression analysis). The results suggest that the proposed simple regression-based prediction models including B 3, B 9, and B 9p outperform the other models including B 1 and B 2 and can be used for more accurate and reliable estimation of specific energy.

  3. Ethnic differences in maternal dietary patterns are largely explained by socio-economic score and integration score: a population-based study.

    Science.gov (United States)

    Sommer, Christine; Sletner, Line; Jenum, Anne K; Mørkrid, Kjersti; Andersen, Lene F; Birkeland, Kåre I; Mosdøl, Annhild

    2013-01-01

    The impact of socio-economic position and integration level on the observed ethnic differences in dietary habits has received little attention. To identify and describe dietary patterns in a multi-ethnic population of pregnant women, to explore ethnic differences in odds ratio (OR) for belonging to a dietary pattern, when adjusted for socio-economic status and integration level and to examine whether the dietary patterns were reflected in levels of biomarkers related to obesity and hyperglycaemia. This cross-sectional study was a part of the STORK Groruddalen study. In total, 757 pregnant women, of whom 59% were of a non-Western origin, completed a food frequency questionnaire in gestational week 28±2. Dietary patterns were extracted through cluster analysis using Ward's method. Four robust clusters were identified where cluster 4 was considered the healthier dietary pattern and cluster 1 the least healthy. All non-European women as compared to Europeans had higher OR for belonging to the unhealthier dietary patterns 1-3 vs. cluster 4. Women from the Middle East and Africa had the highest OR, 21.5 (95% CI 10.6-43.7), of falling into cluster 1 vs. 4 as compared to Europeans. The ORs decreased substantially after adjusting for socio-economic score and integration score. A non-European ethnic origin, low socio-economic and integration scores, conduced higher OR for belonging to clusters 1, 2, and 3 as compared to cluster 4. Significant differences in fasting and 2-h glucose, fasting insulin, glycosylated haemoglobin (HbA1c), insulin resistance (HOMA-IR), and total cholesterol were observed across the dietary patterns. After adjusting for ethnicity, differences in fasting insulin (p=0.015) and HOMA-IR (p=0.040) across clusters remained significant, despite low power. The results indicate that socio-economic and integration level may explain a large proportion of the ethnic differences in dietary patterns.

  4. Selective Oxidative Esterification from Two Different Alcohols via Photoredox Catalysis.

    Science.gov (United States)

    Yi, Hong; Hu, Xia; Bian, Changliang; Lei, Aiwen

    2017-01-10

    Esters functionalities are important building blocks that are extensively used in the chemical industry and academic laboratories. Direct oxidative esterification from easy-available alcohols to esters would be a much more appealing approach, especially using O2 as terminal oxidant. Inputting external energy by photocatalysis for dioxygen activation, a mild and simple method for ester synthesis from two different alcohols has been achieved in this work. This reaction is performed under neutral conditions using O2 as the terminal oxidant. A variety of primary alcohols, especially long chain alcohols and secondary alcohols are tolerated in this system. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Explaining health differences between men and women in later life: a cross-city comparison in Latin America and the Caribbean.

    Science.gov (United States)

    Zunzunegui, Maria-Victoria; Alvarado, Beatriz-Eugenia; Béland, François; Vissandjee, Bilkis

    2009-01-01

    This paper describes differences in health and functional status among older men and women and attempts to anchor the explanations for these differences within a lifecourse perspective. Seven health outcomes for men and women 60 years and older from seven Latin American and Caribbean cities are examined, using data from the 2000 SABE survey (Salud, Bienestar y Envejecimiento-n=10,587). Age-adjusted as well as city- and sex-specific prevalence was estimated for poor self-rated health, comorbidity, mobility limitations, cognitive impairment, depressive symptoms and disability in basic and instrumental activities of daily living. Logistic regressions were fitted to determine if the differences between men and women in each outcome could be explained by differential exposures in childhood (hunger, poverty), adulthood (education, occupation) and old age (income) and/or by differential vulnerability of men and women to these exposures. Sao Paulo, Santiago and Mexico, cities in countries with a high level of income inequalities, presented the highest prevalence of disability, functional limitations and poor physical health for both women and men. Women showed poorer health outcomes as compared with men for all health indicators and in all cities. Controlling for lifecourse exposures in childhood, adulthood and old age did not attenuate these differences. Women's unadjusted and adjusted odds of reporting poor self-rated health, cognitive impairment and basic activities of daily living disability were approximately 50% higher than for men, twice as high for number of comorbidities, depressive symptoms and instrumental activities of daily living disability, and almost three times as high for mobility limitations. Higher vulnerability to lifecourse exposures in women as compared with men was not found, meaning that lifecourse exposures have similar odds of poor health outcomes for men and women. A more integrated understanding of how sex and gender act together to influence

  6. To what extent does sociodemographic composition of the neighbourhood explain regional differences in demand of primary out-of-hours care: a multilevel study.

    Science.gov (United States)

    Jansen, Tessa; Zwaanswijk, Marieke; Hek, Karin; de Bakker, Dinny

    2015-05-06

    In the Netherlands, primary out-of-hours (OOH) care is provided by large scale General Practitioner (GP) cooperatives. GP cooperatives can be contacted by patients living in the area surrounding the GP cooperative (catchment area) at hours when the patient's own general practice is closed. The frequency of primary OOH care use substantially differs between GP cooperative catchment areas. To enable a better match between supply and demand of OOH services, understanding of the factors associated with primary OOH care use is essential. The present study evaluated the contribution of sociodemographic composition of the neighbourhood in explaining differences in primary OOH care use between GP cooperative catchment areas. Data about patients' contacts with primary OOH services (n = 1,668,047) were derived from routine electronic health records of 21 GP cooperatives participating in the NIVEL Primary Care Database in 2012. The study sample is representative for the Dutch population (for age and gender). Data were matched with sociodemographic characteristics (e.g. gender, age, low-income status, degree of urbanisation) on postcode level. Multilevel linear regression models included postcode level (first level), nested within GP cooperative catchment areas (second level). We investigated whether contacts in primary OOH care were associated with neighbourhood sociodemographic characteristics. The demand of primary OOH care was significantly higher in neighbourhoods with more women, low-income households, non-Western immigrants, neighbourhoods with a higher degree of urbanisation, and low neighbourhood socioeconomic status. Conversely, lower demand was associated with neighbourhoods with more 5 to 24 year old inhabitants. Sociodemographic neighbourhood characteristics explained a large part of the variation between GP cooperatives (R-squared ranging from 8% to 52%). Nevertheless, the multilevel models also showed that a considerable amount of variation in demand between GP

  7. The role of poverty in explaining health variations in 7-year-old children from different family structures: findings from the UK Millennium Cohort Study.

    Science.gov (United States)

    Pearce, Anna; Lewis, Hannah; Law, Catherine

    2013-02-01

    Despite rises in reconstituted and lone-parent families, relatively little is known about how the health of children in different family types varies, and the extent to which any differences might be explained by poverty. The authors examined this using cross-sectional data on 13 681 seven-year-olds from the Millennium Cohort Study. The authors estimated RRs and 95% CIs for having poor physical (general health, long-standing illness, injury, overweight, asthma, fits) and mental health (using strengths and difficulties scores) according to family structure using Poisson regression. The authors adjusted for confounders (aRR) and then investigated the role of poverty as a mediator by entering a poverty score (based on income, receipt of benefits, subjective poverty and material deprivation) into the main model. Children living in reconstituted and lone-parent families were at a slight increased risk of poor health compared with those living with two natural parents. Adjusting for poverty tended to remove the elevated risk of poor physical health in children living in lone-parent and reconstituted families. However, for the mental health outcomes, poverty tended to remove the elevated risk for lone parents but not for reconstituted families. For example, the aRR for borderline-abnormal total difficulties fell from 1.45 (1.22 to 1.72) to 1.34 (1.13 to 1.59) in children living in reconstituted families and from 1.29 (1.14 to 1.45) to 1.05 (0.92 to 1.19) in those living with lone parents. Poor physical and mental health was slightly more prevalent in children living in lone-parent or reconstituted families. Poverty reduction may help to reduce these differences, especially for children living with lone parents; however, alternative mechanisms should be also explored, particularly for children living in reconstituted families.

  8. A probabilistic method for testing and estimating selection differences between populations.

    Science.gov (United States)

    He, Yungang; Wang, Minxian; Huang, Xin; Li, Ran; Xu, Hongyang; Xu, Shuhua; Jin, Li

    2015-12-01

    Human populations around the world encounter various environmental challenges and, consequently, develop genetic adaptations to different selection forces. Identifying the differences in natural selection between populations is critical for understanding the roles of specific genetic variants in evolutionary adaptation. Although numerous methods have been developed to detect genetic loci under recent directional selection, a probabilistic solution for testing and quantifying selection differences between populations is lacking. Here we report the development of a probabilistic method for testing and estimating selection differences between populations. By use of a probabilistic model of genetic drift and selection, we showed that logarithm odds ratios of allele frequencies provide estimates of the differences in selection coefficients between populations. The estimates approximate a normal distribution, and variance can be estimated using genome-wide variants. This allows us to quantify differences in selection coefficients and to determine the confidence intervals of the estimate. Our work also revealed the link between genetic association testing and hypothesis testing of selection differences. It therefore supplies a solution for hypothesis testing of selection differences. This method was applied to a genome-wide data analysis of Han and Tibetan populations. The results confirmed that both the EPAS1 and EGLN1 genes are under statistically different selection in Han and Tibetan populations. We further estimated differences in the selection coefficients for genetic variants involved in melanin formation and determined their confidence intervals between continental population groups. Application of the method to empirical data demonstrated the outstanding capability of this novel approach for testing and quantifying differences in natural selection. © 2015 He et al.; Published by Cold Spring Harbor Laboratory Press.

  9. Selective information seeking: can consumers' avoidance of evidence-based information on colorectal cancer screening be explained by the theory of cognitive dissonance?

    Science.gov (United States)

    Steckelberg, Anke; Kasper, Jürgen; Mühlhauser, Ingrid

    2007-08-27

    Evidence-based patient information (EBPI) is a prerequisite for informed decision-making. However, presentation of EBPI may lead to irrational reactions causing avoidance, minimisation and devaluation of the information. To explore whether the theory of cognitive dissonance is applicable to medical decision-making and useful to explain these phenomena. 261 volunteers from Hamburg (157 women), >or=50 years old without diagnosis of colorectal cancer. DESIGN AND VARIABLES: Within an experiment we simulated information seeking on colorectal cancer screening. Consumers' attitudes towards screening were surveyed using a rating scale from -5 (participate in no way) to +5 (participate unconditionally) (independent variable). Using a cover story, participants were asked to sort 5 article headlines according to their reading preferences. The headlines simulated the pro to contra variety of contents to be found in print media about colorectal cancer screening. The dependent variable was the sequence of article headlines. Participants were very much in favour of screening with scores for faecal occult blood test of 4.0 (0.1) and for colonoscopy 3.3 (0.1). According to our hypothesis we found statistically significant positive correlations between the stimuli in favour of screening and attitudes and significant negative correlations between the stimuli against screening and attitudes. The theory of cognitive dissonance is applicable to medical decision-making. It may explain some phenomena of irrational reactions to evidence-based patient information.

  10. Selective information seeking: can consumers' avoidance of evidence-based information on colorectal cancer screening be explained by the theory of cognitive dissonance?

    Directory of Open Access Journals (Sweden)

    Mühlhauser, Ingrid

    2007-08-01

    Full Text Available Background: Evidence-based patient information (EBPI is a prerequisite for informed decision-making. However, presentation of EBPI may lead to irrational reactions causing avoidance, minimisation and devaluation of the information. Objective: To explore whether the theory of cognitive dissonance is applicable to medical decision-making and useful to explain these phenomena. Setting and participants: 261 volunteers from Hamburg (157 women, ≥50 years old without diagnosis of colorectal cancer. Design and variables: Within an experiment we simulated information seeking on colorectal cancer screening. Consumers’ attitudes towards screening were surveyed using a rating scale from -5 (participate in no way to +5 (participate unconditionally (independent variable. Using a cover story, participants were asked to sort 5 article headlines according to their reading preferences. The headlines simulated the pro to contra variety of contents to be found in print media about colorectal cancer screening. The dependent variable was the sequence of article headlines. Results: Participants were very much in favour of screening with scores for faecal occult blood test of 4.0 (0.1 and for colonoscopy 3.3 (0.1. According to our hypothesis we found statistically significant positive correlations between the stimuli in favour of screening and attitudes and significant negative correlations between the stimuli against screening and attitudes. Conclusion: The theory of cognitive dissonance is applicable to medical decision-making. It may explain some phenomena of irrational reactions to evidence-based patient information.

  11. Obesity explains gender differences in the association between education level and metabolic syndrome in South Korea: the results from the Korean National Health and Nutrition Examination Survey 2010.

    Science.gov (United States)

    Ko, Ki Dong; Cho, BeLong; Lee, Won Chul; Lee, Hae Won; Lee, Hyun Ki; Oh, Bum Jo

    2015-03-01

    This study aimed to examine the association of educational level with metabolic syndrome (MS) and its risk factors by gender in South Korea. A total of 6178 participants aged 20 years or older from The Fifth Korean National Health and Nutrition Examination Survey were included in this study. A generalized linear model and adjusted proportion were used to identify educational disparities in MS, its components, and its risk factors (smoking, high-risk alcohol consumption, obesity, and stress). In women, a clearly inverse association between education level and MS were observed with significant trend, and the decreasing trends of all risk factors across education quartiles were in line with the inverse association. However, the association between education level and MS was not observed with a significant trend among men. An opposite trend of risk factors across education levels was shown in men, with an increasing trend for obesity and decreasing trends for smoking and high-risk alcohol consumption. These findings demonstrate that obesity can explain gender differences in the association between education level and MS in South Korea. © 2013 APJPH.

  12. Gender Differences in Resistance to Schooling: The Role of Dynamic Peer-Influence and Selection Processes.

    Science.gov (United States)

    Geven, Sara; O Jonsson, Jan; van Tubergen, Frank

    2017-12-01

    Boys engage in notably higher levels of resistance to schooling than girls. While scholars argue that peer processes contribute to this gender gap, this claim has not been tested with longitudinal quantitative data. This study fills this lacuna by examining the role of dynamic peer-selection and influence processes in the gender gap in resistance to schooling (i.e., arguing with teachers, skipping class, not putting effort into school, receiving punishments at school, and coming late to class) with two-wave panel data. We expect that, compared to girls, boys are more exposed and more responsive to peers who exhibit resistant behavior. We estimate hybrid models on 5448 students from 251 school classes in Sweden (14-15 years, 49% boys), and stochastic actor-based models (SIENA) on a subsample of these data (2480 students in 98 classes; 49% boys). We find that boys are more exposed to resistant friends than girls, and that adolescents are influenced by the resistant behavior of friends. These peer processes do not contribute to a widening of the gender gap in resistance to schooling, yet they contribute somewhat to the persistence of the initial gender gap. Boys are not more responsive to the resistant behavior of friends than girls. Instead, girls are influenced more by the resistant behavior of lower status friends than boys. This explains to some extent why boys increase their resistance to schooling more over time. All in all, peer-influence and selection processes seem to play a minor role in gender differences in resistance to schooling. These findings nuance under investigated claims that have been made in the literature.

  13. SIZE SELECTION IN DIVING TUFTED DUCKS AYTHYA-FULIGULA EXPLAINED BY DIFFERENTIAL HANDLING OF SMALL AND LARGE MUSSELS DREISSENA-POLYMORPHA

    NARCIS (Netherlands)

    DELEEUW, JJ; VANEERDEN, MR

    1992-01-01

    We studied prey size selection of Tufted Ducks feeding on fresh-water mussels under semi-natural conditions. In experiments with non-diving birds, we found that Tufted Ducks use two techniques to handle mussels. Mussels less than 16 mm in length are strained from a waterflow generated in the bill

  14. Understanding "Fairness" in Student Selection: Are There Differences and Does It Make a Difference Anyway?

    Science.gov (United States)

    Pitman, Tim

    2016-01-01

    Universities are required to adopt "fair" student admission practices, yet understandings of fairness in student selection are contested. This paper uses an analysis of the admission policies of Australia's public universities to critically examine the use and application of notions of fairness. A further analysis of enrolment data is…

  15. IEE wiring regulations explained and illustrated

    CERN Document Server

    Scaddan, Brian

    2013-01-01

    The IEE Wiring Regulations Explained and Illustrated, Second Edition discusses the recommendations of the IEE Regulations for the Electrical Equipment of Buildings for the safe selection or erection of wiring installations. The book emphasizes earthing, bonding, protection, and circuit design of electrical wirings. The text reviews the fundamental requirements for safety, earthing systems, the earth fault loop impedance, and supplementary bonding. The book also describes the different types of protection, such as protection against mechanical damage, overcurrent, under voltage (which prevents

  16. Using the satellite-derived normalized difference vegetation index (NDVI) to explain ranging patterns in a lek-breeding antelope: the importance of scale.

    Science.gov (United States)

    Bro-Jørgensen, Jakob; Brown, Molly E; Pettorelli, Nathalie

    2008-11-01

    Lek-breeding species are characterized by a negative association between territorial resource availability and male mating success; however, the impact of resources on the overall distribution patterns of the two sexes in lek systems is not clear. The normalized difference vegetation index (NDVI) has recently emerged as a powerful proxy measure for primary productivity, allowing the links between the distributions of animals and resources to be explored. Using NDVI at four spatial resolutions, we here investigate how the distribution of the two sexes in a lek-breeding population of topi antelopes relates to resource abundance before and during the rut. We found that in the dry season preceding the rut, topi density correlated positively with NDVI at the large, but not the fine, scale. This suggests that before the rut, when resources were relatively scant, topi preferred pastures where green grass was widely abundant. The pattern was less pronounced in males, suggesting that the need for territorial attendance prevents males from tracking resources as freely as females do. During the rut, which occurs in the wet season, both male and female densities correlated negatively with NDVI at the fine scale. At this time, resources were generally plentiful and the results suggest that, rather than by resource maximization, distribution during the rut was determined by benefits of aggregating on relatively resource-poor leks for mating, and possibly antipredator, purposes. At the large scale, no correlation between density and NDVI was found during the rut in either sex, which can be explained by leks covering areas too small to be reflected at this resolution. The study illustrates that when investigating spatial organization, it is important: (1) to choose the appropriate analytic scale, and (2) to consider behavioural as well as strictly ecological factors.

  17. The role of perceived barriers in explaining socio-economic status differences in adherence to the fruit, vegetable and fish guidelines in older adults: a mediation study.

    Science.gov (United States)

    Dijkstra, S Coosje; Neter, Judith E; van Stralen, Maartje M; Knol, Dirk L; Brouwer, Ingeborg A; Huisman, Martijn; Visser, Marjolein

    2015-04-01

    We aimed to identify barriers for meeting the fruit, vegetable and fish guidelines in older Dutch adults and to investigate socio-economic status (SES) differences in these barriers. Furthermore, we examined the mediating role of these barriers in the association between SES and adherence to these guidelines. Cross-sectional. Longitudinal Aging Study Amsterdam (LASA), the Netherlands. We used data from 1057 community-dwelling adults, aged 55-85 years. SES was measured by level of education and household income. An FFQ was used to assess dietary intake and barriers were measured with a self-reported lifestyle questionnaire. Overall, 48.9 % of the respondents perceived a barrier to adhere to the fruit guideline, 40.0 % for the vegetable and 51.1 % for the fish guideline. The most frequently perceived barriers to meet the guidelines were the high price of fruit and fish and a poor appetite for vegetables. Lower-SES groups met the guidelines less often and perceived more barriers. The association between income and adherence to the fruit guideline was mediated by 'perceiving any barrier to meet the fruit guideline' and the barrier 'dislike fruit'. The association between income and adherence to the fish guideline was mediated by 'perceiving any barrier to meet the fish guideline' and the barrier 'fish is expensive'. Perceived barriers for meeting the dietary guidelines are common in older adults, especially in lower-SES groups. These barriers and in particular disliking and cost concerns explained the lower adherence to the guidelines for fruit and fish in lower-income groups in older adults.

  18. Comparing trainers’ reports of clicker use to the use of clickers in applied research studies: methodological differences may explain conflicting results

    Directory of Open Access Journals (Sweden)

    Lynna C Feng

    2017-02-01

    Full Text Available Clicker training refers to an animal training technique, derived from laboratory-based studies of animal learning and behaviour, in which a reward-predicting signal is delivered immediately following performance of a desired behaviour, and is subsequently followed by a reward. While clicker training is popular amongst dog training practitioners, scientific evaluation in applied settings has been largely unsuccessful in replicating the benefits of reward-predicting signals seen in laboratory animal studies. Here we present an analysis of dog trainers’ advice and perceptions, conducted to better understand clicker training as it occurs in the dog training industry. Twenty-five sources (13 interviews with dog trainers, 5 websites, and 7 books were analysed using a deductive content analysis procedure. We found that, for many sources, “clicker training” referred not only to the technique, but also to a philosophy of training that emphasises positive reinforcement and the deliberate application of Learning Theory principles. Many sources reported that clicker training was fun, for both dog and handler, but that it could be frustrating for handlers to learn and sometimes cumbersome to juggle the extra equipment. In addition, while most sources recommended clicker training particularly when training new behaviours, many stated that it was no longer needed once the dog had learned the desired behaviour. When comparing industry recommendations to methods used in applied studies, different criteria were used for predictor signal conditioning. Inadequate conditioning of the predictor signal in empirical evaluations could partly explain the lack of learning benefits in applied studies. While future research is needed to verify the practitioner beliefs in a wider population, these results provide an in-depth description of what clicker training is, at least for the sources analysed, and a potential starting point for understanding methodological

  19. Two-stage processing of sounds explains behavioral performance variations due to changes in stimulus contrast and selective attention: an MEG study.

    Directory of Open Access Journals (Sweden)

    Jaakko Kauramäki

    Full Text Available Selectively attending to task-relevant sounds whilst ignoring background noise is one of the most amazing feats performed by the human brain. Here, we studied the underlying neural mechanisms by recording magnetoencephalographic (MEG responses of 14 healthy human subjects while they performed a near-threshold auditory discrimination task vs. a visual control task of similar difficulty. The auditory stimuli consisted of notch-filtered continuous noise masker sounds, and of 1020-Hz target tones occasionally (p = 0.1 replacing 1000-Hz standard tones of 300-ms duration that were embedded at the center of the notches, the widths of which were parametrically varied. As a control for masker effects, tone-evoked responses were additionally recorded without masker sound. Selective attention to tones significantly increased the amplitude of the onset M100 response at ~100 ms to the standard tones during presence of the masker sounds especially with notches narrower than the critical band. Further, attention modulated sustained response most clearly at 300-400 ms time range from sound onset, with narrower notches than in case of the M100, thus selectively reducing the masker-induced suppression of the tone-evoked response. Our results show evidence of a multiple-stage filtering mechanism of sensory input in the human auditory cortex: 1 one at early (~100 ms latencies bilaterally in posterior parts of the secondary auditory areas, and 2 adaptive filtering of attended sounds from task-irrelevant background masker at longer latency (~300 ms in more medial auditory cortical regions, predominantly in the left hemisphere, enhancing processing of near-threshold sounds.

  20. Factors explaining the difference of total homocysteine between men and women in the European Investigation Into Cancer and Nutrition Potsdam study.

    Science.gov (United States)

    Dierkes, J; Jeckel, A; Ambrosch, A; Westphal, S; Luley, C; Boeing, H

    2001-06-01

    Interestingly, plasma total homocysteine (tHcy) concentration is consistently higher in men than in women. This observation deserves further investigations because elevated tHcy concentrations have been shown to be independently associated with coronary, peripheral, and cerebral vascular diseases. It was the aim of the present study to define major determinants of plasma tHcy in a healthy middle-aged German population under particular consideration of the gender factor. The study population was obtained from an ongoing recruitment procedure for a cohort study and comprised 336 men and women, aged 40 to 65 years. Exclusion criteria were elevated creatinine levels in blood, history of skin or atherosclerotic diseases, current use of vitamins or other supplements, and heavy smoking. Plasma tHcy, folate, vitamin B12, vitamin B6, creatinine, testosterone and estradiol, protein, and hematocrit were measured. Fat-free mass was assessed by skinfold thickness. The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR), a key enzyme of folate and homocysteine metabolism, was determined by polymerase chain reaction (PCR) with restriction enzyme analysis. In this population, plasma tHcy ranged from 5 to 46 micromol/L. The frequency of the T allele of the MTHFR was 0.29, which is lower than in other populations. A total of 54.2% of this population was homozygote for the wild-type, 39.6% heterozygote, and 6.2% homozygote for the mutation. tHcy correlated negatively with folate and cobalamin concentration in blood and positively with creatinine. No correlation was seen with vitamin B6. From the gender-related variables, tHyc correlated significantly with fat-free mass and testosterone and inversely with estradiol. The difference between gender with regard to tHcy was mainly explained by differences in fat-free mass, but also by estradiol concentrations. The following contributions to the variation of tHcy were seen in a multivariate regression model: plasma

  1. Altered Ca2+ kinetics associated with α-actinin-3 deficiency may explain positive selection for ACTN3 null allele in human evolution.

    Directory of Open Access Journals (Sweden)

    Stewart I Head

    Full Text Available Over 1.5 billion people lack the skeletal muscle fast-twitch fibre protein α-actinin-3 due to homozygosity for a common null polymorphism (R577X in the ACTN3 gene. α-Actinin-3 deficiency is detrimental to sprint performance in elite athletes and beneficial to endurance activities. In the human genome, it is very difficult to find single-gene loss-of-function variants that bear signatures of positive selection, yet intriguingly, the ACTN3 null variant has undergone strong positive selection during recent evolution, appearing to provide a survival advantage where food resources are scarce and climate is cold. We have previously demonstrated that α-actinin-3 deficiency in the Actn3 KO mouse results in a shift in fast-twitch fibres towards oxidative metabolism, which would be more "energy efficient" in famine, and beneficial to endurance performance. Prolonged exposure to cold can also induce changes in skeletal muscle similar to those observed with endurance training, and changes in Ca2+ handling by the sarcoplasmic reticulum (SR are a key factor underlying these adaptations. On this basis, we explored the effects of α-actinin-3 deficiency on Ca2+ kinetics in single flexor digitorum brevis muscle fibres from Actn3 KO mice, using the Ca2+-sensitive dye fura-2. Compared to wild-type, fibres of Actn3 KO mice showed: (i an increased rate of decay of the twitch transient; (ii a fourfold increase in the rate of SR Ca2+ leak; (iii a threefold increase in the rate of SR Ca2+ pumping; and (iv enhanced maintenance of tetanic Ca2+ during fatigue. The SR Ca2+ pump, SERCA1, and the Ca2+-binding proteins, calsequestrin and sarcalumenin, showed markedly increased expression in muscles of KO mice. Together, these changes in Ca2+ handling in the absence of α-actinin-3 are consistent with cold acclimatisation and thermogenesis, and offer an additional explanation for the positive selection of the ACTN3 577X null allele in populations living in cold environments

  2. Homage to Bateman: sex roles predict sex differences in sexual selection.

    Science.gov (United States)

    Fritzsche, Karoline; Arnqvis, Göran

    2013-07-01

    Classic sex role theory predicts that sexual selection should be stronger in males in taxa showing conventional sex roles and stronger in females in role reversed mating systems. To test this very central prediction and to assess the utility of different measures of sexual selection, we estimated sexual selection in both sexes in four seed beetle species with divergent sex roles using a novel experimental design. We found that sexual selection was sizeable in females and the strength of sexual selection was similar in females and males in role-reversed species. Sexual selection was overall significantly stronger in males than in females and residual selection formed a substantial component of net selection in both sexes. Furthermore, sexual selection in females was stronger in role-reversed species compared to species with conventional sex roles. Variance-based measures of sexual selection (the Bateman gradient and selection opportunities) were better predictors of sexual dimorphism in reproductive behavior and morphology across species compared to trait-based measures (selection differentials). Our results highlight the importance of using assays that incorporate components of fitness manifested after mating. We suggest that the Bateman gradient is generally the most informative measure of the strength of sexual selection in comparisons across sexes and/or species. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  3. Body size and pubertal development explain ethnic differences in structural geometry at the femur in Asian, Hispanic and white early adolescent girls living in the US

    Science.gov (United States)

    Variation in structural geometry is present in adulthood, but when this variation arises and what influences this variation prior to adulthood remains poorly understood. Ethnicity is commonly the focus of research of skeletal integrity and appears to explain some of the variation in quantification o...

  4. Can resource dilution explain differences in height by birth order and family size? A study of 389,287 male recruits in twentieth-century Netherlands

    NARCIS (Netherlands)

    Stradford, L.; van Poppel, F.W.A.; Lumey, L.H.

    2017-01-01

    ‘Resource dilution’ has been invoked as a possible mechanism to explain the inverse relation between sibship size and sibling heights in European populations (Öberg, 2015). Alternative explanations include confounding of the relation by other measured or unmeasured family characteristics including

  5. Sex differences in trajectories of depressive symptoms among older Taiwanese: the contribution of selected stressors and social factors.

    Science.gov (United States)

    Glei, Dana A; Goldman, Noreen; Liu, I-Wen; Weinstein, Maxine

    2013-01-01

    We assessed female-male differences in depressive symptoms among older Taiwanese and quantified the contribution of sex differences in exposure and response to selected covariates in explaining the gap. Using data from six survey waves over 18 years for a nationally representative cohort of 4049 Taiwanese aged 60+, we employed growth curve analysis to model individual-level trajectories of depressive symptoms across age. Among older Taiwanese, women's disadvantage with respect to social position and employment accounted for about 40% of the sex difference in depressive symptoms. Sex differences in decision control and exposure to widowhood and financial decline played surprisingly little role. Although we found no evidence that the effects of marriage, recent widowhood or recent child death varied by sex, living apart from one's children appeared to be more detrimental for women than for men in this society. Moreover, the effect of living with children depended on the arrangement: living with an unmarried son was more strongly associated with depressive symptoms than living with a married son and daughter-in-law. Sex differentials in social position and employment are major contributors to the sex difference in depressive symptoms among older Taiwanese, yet sex differences in exposure or response to selected stressors appear to play little role. Differential vulnerabilities to particular living arrangements may also contribute to women's excess psychological distress, although more research is needed to elucidate the mechanisms by which living arrangements influence depressive symptoms in Taiwan.

  6. Differential responses in ammonia excretion, sodium fluxes and gill permeability explain different sensitivities to acute high environmental ammonia in three freshwater teleosts.

    Science.gov (United States)

    Liew, Hon Jung; Sinha, Amit Kumar; Nawata, C Michele; Blust, Ronny; Wood, Chris M; De Boeck, Gudrun

    2013-01-15

    for 3 h: J(in)(Na) was significantly inhibited while considerable activation of J(out)(Na) was observed. Diffusive water efflux rates and net K(+) loss rates across the gills were enhanced during HEA only in trout, indicating an increment in gill transcellular permeability. Transepithelial potential was increased in all the species during ammonia exposure, but to the least extent in goldfish. Overall, for several different physiological systems, trout were most disturbed, and goldfish were least disturbed by HEA, helping to explain the differential ammonia tolerance of the three species. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Differences in selected medical care parameters in rheumatic disease ward patients of different ages of life.

    Science.gov (United States)

    Pobrotyn, Piotr; Susło, Robert; Witczak, Izabela; Milczanowski, Piotr; Drobnik, Jarosław

    2016-01-01

    Rheumatic diseases are becoming more and more common in Poland with the ageing of the population. Nearly 18% of the total hospital admissions in Poland result from rheumatic diseases, which was equivalent to 350 thousand cases in the year 2008. These diseases tend to last for many decades, decreasing both the quality of life and income of the patients as well as increasing the medical institutions' workload and society's financial burden. The aim of the study was to determine whether the medical care parameters in a rheumatic disease hospital ward show any significant differences among different patient age groups - especially such that would support taking them into account as a basis for adjusting the financial coverage level of medical services. Data on hospitalizations at the Rheumatic Diseases Ward of Wroclaw University Hospital in Wroclaw in the years 2009-2015 were analyzed, taking into account the age groups, number of hospital admissions, their duration and causes. Relevant statistical data analysis was performed. The study revealed that the number of old patients hospitalized at the rheumatic diseases ward increased over the last 6 years and that such statistically significant differences do exist: on average the old patients not only tend to stay much longer at the hospital, but also suffer from a different and more diverse spectrum of diseases in comparison to their younger counterparts. The detected differences in medical care parameters support the need for more individualized medical care and increased cost of the hospital stay in the case of older patients. Consequently, those factors justify the necessity to increase the value of medical services in the case of old patients, possibly also taking into account the variation between age subgroups.

  8. Reciprocity explains food sharing in humans and other primates independent of kin selection and tolerated scrounging: a phylogenetic meta-analysis.

    Science.gov (United States)

    Jaeggi, Adrian V; Gurven, Michael

    2013-10-07

    Helping, i.e. behaviour increasing the fitness of others, can evolve when directed towards kin or reciprocating partners. These predictions have been tested in the context of food sharing both in human foragers and non-human primates. Here, we performed quantitative meta-analyses on 32 independent study populations to (i) test for overall effects of reciprocity on food sharing while controlling for alternative explanations, methodological biases, publication bias and phylogeny and (ii) compare the relative effects of reciprocity, kinship and tolerated scrounging, i.e. sharing owing to costs imposed by others. We found a significant overall weighted effect size for reciprocity of r = 0.20-0.48 for the most and least conservative measure, respectively. Effect sizes did not differ between humans and other primates, although there were species differences in in-kind reciprocity and trade. The relative effect of reciprocity in sharing was similar to those of kinship and tolerated scrounging. These results indicate a significant independent contribution of reciprocity to human and primate helping behaviour. Furthermore, similar effect sizes in humans and primates speak against cognitive constraints on reciprocity. This study is the first to use meta-analyses to quantify these effects on human helping and to directly compare humans and other primates.

  9. Bio-economic evaluation of implementing trawl fishing gear with different selectivity

    DEFF Research Database (Denmark)

    Kronbak, Lone Grønbæk; Nielsen, J. Rasmus; Jørgensen, Ole A.

    2009-01-01

    with a baseline. The results from the evaluation are indicators for the consequences on ecological and economic levels. The results show that implementation of different selective fishing gear in the Kattegat and Skagerrak mixed trawl fisheries generally implies a trade off over time between rebuilding the stocks...... and economic loss. Moreover, the analysis shows that implementation of more selective gear is not always beneficial....

  10. When species' ranges meet: assessing differences in habitat selection between sympatric large carnivores.

    Science.gov (United States)

    Rauset, Geir Rune; Mattisson, Jenny; Andrén, Henrik; Chapron, Guillaume; Persson, Jens

    2013-07-01

    Differentiation in habitat selection among sympatric species may depend on niche partitioning, species interactions, selection mechanisms and scales considered. In a mountainous area in Sweden, we explored hierarchical habitat selection in Global Positioning System-collared individuals of two sympatric large carnivore species; an obligate predator, the Eurasian lynx (Lynx lynx), and a generalist predator and scavenger, the wolverine (Gulo gulo). Although the species' fundamental niches differ widely, their ranges overlap in this area where they share a prey base and main cause of mortality. Both lynx and wolverines selected for steep and rugged terrain in mountainous birch forest and in heaths independent of scale and available habitats. However, the selection of lynx for their preferred habitats was stronger when they were forming home ranges and they selected the same habitats within their home ranges independent of home range composition. Wolverines displayed a greater variability when selecting home ranges and habitat selection also varied with home range composition. Both species selected for habitats that promote survival through limited encounters with humans, but which also are rich in prey, and selection for these habitats was accordingly stronger in winter when human activity was high and prey density was low. We suggest that the observed differences between the species result primarily from different foraging strategies, but may also depend on differences in ranging and resting behaviour, home range size, and relative density of each species. Our results support the prediction that sympatric carnivores with otherwise diverging niches can select for the same resources when sharing main sources of food and mortality.

  11. Quantitative analysis of the water occupancy around the selectivity filter of a K+ channel in different gating modes.

    Science.gov (United States)

    Weingarth, Markus; van der Cruijsen, Elwin A W; Ostmeyer, Jared; Lievestro, Sylke; Roux, Benoît; Baldus, Marc

    2014-02-05

    Recovery in K(+) channels, that is, the transition from the inactivated nonconductive selectivity filter conformation toward the conductive conformation, occurs on a time scale of the order of seconds, which is astonishingly long, given that the structural differences among the filter conformations are faint (channels. Using a combination of solid-state NMR spectroscopy (ssNMR) and long molecular dynamics simulations, we sketch a high-resolution map of the spatial and temporal distribution of water behind the selectivity filter of a membrane-embedded K(+) channel in two different gating modes. Our study demonstrates that buried water molecules with long residence times are spread all along the rear of the inactivated filter, which explains the recovery kinetics. In contrast, the same region of the structure appears to be dewetted when the selectivity filter is in the conductive state. Using proton-detected ssNMR on fully protonated channels, we demonstrate the presence of a pathway that allows for the interchange of buried and bulk water, as required for a functional influence of buried water on recovery and slow inactivation. Furthermore, we provide direct experimental evidence for the presence of additional ordered water molecules that surround the filter and that are modulated by the channel's gating mode.

  12. Stability of selected volatile contact allergens in different patch test chambers under different storage conditions

    DEFF Research Database (Denmark)

    Mose, Kristian Fredløv; Andersen, Klaus Ejner; Christensen, Lars Porskjaer

    2012-01-01

    storage conditions. Methods. Petrolatum samples of methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (2-HEMA), 2-hydroxypropyl acrylate (2-HPA), cinnamal and eugenol in patch test concentrations were stored in three different test chambers (IQ chamber™, IQ Ultimate™, and Van der Bend® transport...... during storage in the refrigerator. For these two chamber systems, the contact allergen concentration dropped below the stability limit in the following order: MMA, cinnamal, 2-HPA, eugenol, and 2-HEMA. In the Van der Bend® transport container, the contact allergens exhibited acceptable stability under...... both storage conditions, whereas MMA and 2-HPA required cool storage for maintenance of the limit. Conclusion. The Van der Bend® transport container was the best device for storage of samples of volatile contact allergens....

  13. Different cortical mechanisms for spatial vs. feature-based attentional selection in visual working memory

    Directory of Open Access Journals (Sweden)

    Anna Heuer

    2016-08-01

    Full Text Available The limited capacity of visual working memory necessitates attentional mechanisms that selectively update and maintain only the most task-relevant content. Psychophysical experiments have shown that the retroactive selection of memory content can be based on visual properties such as location or shape, but the neural basis for such differential selection is unknown. For example, it is not known if there are different cortical modules specialized for spatial versus feature-based mnemonic attention, in the same way that has been demonstrated for attention to perceptual input. Here, we used transcranial magnetic stimulation (TMS to identify areas in human parietal and occipital cortex involved in the selection of objects from memory based on cues to their location (spatial information or their shape (featural information. We found that TMS over the supramarginal gyrus (SMG selectively facilitated spatial selection, whereas TMS over the lateral occipital cortex selectively enhanced feature-based selection for remembered objects in the contralateral visual field. Thus, different cortical regions are responsible for spatial vs. feature-based selection of working memory representations. Since the same regions are involved in attention to external events, these new findings indicate overlapping mechanisms for attentional control over perceptual input and mnemonic representations.

  14. Sympatric Masticophis flagellum and Coluber constrictor select vertebrate prey at different levels of taxonomy

    Science.gov (United States)

    Halstead, B.J.; Mushinsky, H.R.; McCoy, E.D.

    2008-01-01

    Masticophis flagellum (Coachwhip) and Coluber constrictor (Eastern Racer) are widespread North American snakes with similar foraging modes and habits. Little is known about the selection of prey by either species, and despite their apparently similar foraging habits, comparative studies of the foraging ecology of sympatric M. flagellum and C. constrictor are lacking. We examined the foraging ecology and prey selection of these actively foraging snakes in xeric, open-canopied Florida scrub habitat by defining prey availability separately for each snake to elucidate mechanisms underlying geographic, temporal, and interspecific variation in predator diets. Nineteen percent of M. flagellum and 28% of C. constrictor contained stomach contents, and most snakes contained only one prey item. Mean relative prey mass for both species was less than 10%. Larger C. constrictor consumed larger prey than small individuals, but this relationship disappeared when prey size was scaled to snake size. Masticophis flagellum was selective at the prey category level, and positively selected lizards and mammals; however, within these categories it consumed prey species in proportion to their availability. In contrast, C. constrictor preyed upon prey categories opportunistically, but was selective with regard to species. Specifically, C. constrictor positively selected Hyla femoralis (Pine Woods Treefrog) and negatively selected Bufo querclcus (Oak Toad), B. terrestris (Southern Toad), and Gastrophryne carolinensis (Eastern Narrowmouth Toad). Thus, despite their similar foraging habits, M. flagellum and C. constrictor select different prey and are selective of prey at different levels of taxonomy. ?? 2008 by the American Society of Ichthyologists and Herpetologists.

  15. Selection of similar single domain antibodies from two immune VHH libraries obtained from two alpacas by using different selection methods.

    Science.gov (United States)

    Li, Tengfei; Vandesquille, Matthias; Bay, Sylvie; Dhenain, Marc; Delatour, Benoît; Lafaye, Pierre

    2017-08-01

    The two most used methods to select camelid single-domain antibody-fragments (VHHs) are: displaying their repertoires on the surface of filamentous bacteriophages (phage display) or linking them to ribosomes (ribosome display). In this study, we compared specific VHHs isolated from two different immune libraries coming from two different alpacas by using these two selection methods. Three anti-GFAP (glial fibrillary acidic protein) VHHs were derived from an immune library obtained by ribosome display after immunization of one alpaca with purified GFAP, a protein expressed by astroglial cells. In parallel, three other anti-GFAP VHHs were derived from an immune library by phage display after immunization of another alpaca with a human brain tissue extract containing GFAP. All the VHHs were closely related and one VHH was found to be strictly identical in both studies. This highlights the selection pressure exerted by the camelid immune system to shape the paratope of an antibody against a defined antigen. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  16. Sexual Selection and the differences between the sexes in Mandrills (Mandrillus sphinx).

    Science.gov (United States)

    Setchell, Joanna M

    2016-01-01

    Sexual selection has become a major focus in evolutionary and behavioral ecology. It is also a popular research topic in primatology. I use studies of mandrills (Mandrillus sphinx), a classic example of extravagant armaments and ornaments in animals, to exemplify how a long-term, multidisciplinary approach that integrates field observations with laboratory methods can contribute to on-going theoretical debates in the field of sexual selection. I begin with a brief summary of the main concepts of sexual selection theory and the differences between the sexes. I then introduce mandrills and the study population and review mandrill life history, the ontogeny of sex differences, and maternal effects. Next, I focus on male-male competition and female choice, followed by the less well-studied questions of female-female competition and male choice. This review shows how different reproductive priorities lead to very different life histories and divergent adaptations in males and females. It demonstrates how broadening traditional perspectives on sexual selection beyond the ostentatious results of intense sexual selection on males leads to an understanding of more subtle and cryptic forms of competition and choice in both sexes and opens many productive avenues in the study of primate reproductive strategies. These include the potential for studies of postcopulatory selection, female intrasexual competition, and male choice. These studies of mandrills provide comparison and, I hope, inspiration for studies of both other polygynandrous species and species with mating systems less traditionally associated with sexual selection. © 2016 Wiley Periodicals, Inc.

  17. Matlab for engineers explained

    CERN Document Server

    Gustafsson, Fredrik

    2003-01-01

    This book is written for students at bachelor and master programs and has four different purposes, which split the book into four parts: 1. To teach first or early year undergraduate engineering students basic knowledge in technical computations and programming using MATLAB. The first part starts from first principles and is therefore well suited both for readers with prior exposure to MATLAB but lacking a solid foundational knowledge of the capabilities of the system and readers not having any previous experience with MATLAB. The foundational knowledge gained from these interactive guided tours of the system will hopefully be sufficient for an effective utilization of MATLAB in the engineering profession, in education and in research. 2. To explain the foundations of more advanced use of MATLAB using the facilities added the last couple of years, such as extended data structures, object orientation and advanced graphics. 3. To give an introduction to the use of MATLAB in typical undergraduate courses in elec...

  18. The role of positive selection in determining the molecular cause of species differences in disease

    Directory of Open Access Journals (Sweden)

    Foord Steven M

    2008-10-01

    Full Text Available Abstract Background Related species, such as humans and chimpanzees, often experience the same disease with varying degrees of pathology, as seen in the cases of Alzheimer's disease, or differing symptomatology as in AIDS. Furthermore, certain diseases such as schizophrenia, epithelial cancers and autoimmune disorders are far more frequent in humans than in other species for reasons not associated with lifestyle. Genes that have undergone positive selection during species evolution are indicative of functional adaptations that drive species differences. Thus we investigate whether biomedical disease differences between species can be attributed to positively selected genes. Results We identified genes that putatively underwent positive selection during the evolution of humans and four mammals which are often used to model human diseases (mouse, rat, chimpanzee and dog. We show that genes predicted to have been subject to positive selection pressure during human evolution are implicated in diseases such as epithelial cancers, schizophrenia, autoimmune diseases and Alzheimer's disease, all of which differ in prevalence and symptomatology between humans and their mammalian relatives. In agreement with previous studies, the chimpanzee lineage was found to have more genes under positive selection than any of the other lineages. In addition, we found new evidence to support the hypothesis that genes that have undergone positive selection tend to interact with each other. This is the first such evidence to be detected widely among mammalian genes and may be important in identifying molecular pathways causative of species differences. Conclusion Our dataset of genes predicted to have been subject to positive selection in five species serves as an informative resource that can be consulted prior to selecting appropriate animal models during drug target validation. We conclude that studying the evolution of functional and biomedical disease differences

  19. The role of positive selection in determining the molecular cause of species differences in disease.

    Science.gov (United States)

    Vamathevan, Jessica J; Hasan, Samiul; Emes, Richard D; Amrine-Madsen, Heather; Rajagopalan, Dilip; Topp, Simon D; Kumar, Vinod; Word, Michael; Simmons, Mark D; Foord, Steven M; Sanseau, Philippe; Yang, Ziheng; Holbrook, Joanna D

    2008-10-06

    Related species, such as humans and chimpanzees, often experience the same disease with varying degrees of pathology, as seen in the cases of Alzheimer's disease, or differing symptomatology as in AIDS. Furthermore, certain diseases such as schizophrenia, epithelial cancers and autoimmune disorders are far more frequent in humans than in other species for reasons not associated with lifestyle. Genes that have undergone positive selection during species evolution are indicative of functional adaptations that drive species differences. Thus we investigate whether biomedical disease differences between species can be attributed to positively selected genes. We identified genes that putatively underwent positive selection during the evolution of humans and four mammals which are often used to model human diseases (mouse, rat, chimpanzee and dog). We show that genes predicted to have been subject to positive selection pressure during human evolution are implicated in diseases such as epithelial cancers, schizophrenia, autoimmune diseases and Alzheimer's disease, all of which differ in prevalence and symptomatology between humans and their mammalian relatives. In agreement with previous studies, the chimpanzee lineage was found to have more genes under positive selection than any of the other lineages. In addition, we found new evidence to support the hypothesis that genes that have undergone positive selection tend to interact with each other. This is the first such evidence to be detected widely among mammalian genes and may be important in identifying molecular pathways causative of species differences. Our dataset of genes predicted to have been subject to positive selection in five species serves as an informative resource that can be consulted prior to selecting appropriate animal models during drug target validation. We conclude that studying the evolution of functional and biomedical disease differences between species is an important way to gain insight into

  20. Feature selection using genetic algorithm for breast cancer diagnosis: experiment on three different datasets

    Directory of Open Access Journals (Sweden)

    Shokoufeh Aalaei

    2016-05-01

    Full Text Available Objective(s: This study addresses feature selection for breast cancer diagnosis. The present process uses a wrapper approach using GA-based on feature selection and PS-classifier. The results of experiment show that the proposed model is comparable to the other models on Wisconsin breast cancer datasets. Materials and Methods: To evaluate effectiveness of proposed feature selection method, we employed three different classifiers artificial neural network (ANN and PS-classifier and genetic algorithm based classifier (GA-classifier on Wisconsin breast cancer datasets include Wisconsin breast cancer dataset (WBC, Wisconsin diagnosis breast cancer (WDBC, and Wisconsin prognosis breast cancer (WPBC. Results: For WBC dataset, it is observed that feature selection improved the accuracy of all classifiers expect of ANN and the best accuracy with feature selection achieved by PS-classifier. For WDBC and WPBC, results show feature selection improved accuracy of all three classifiers and the best accuracy with feature selection achieved by ANN. Also specificity and sensitivity improved after feature selection. Conclusion: The results show that feature selection can improve accuracy, specificity and sensitivity of classifiers. Result of this study is comparable with the other studies on Wisconsin breast cancer datasets.

  1. Prospectively measured lifestyle factors and BMI explain differences in health-related quality of life between colorectal cancer patients with and without comorbid diabetes

    DEFF Research Database (Denmark)

    Vissers, Pauline A J; Thong, Melissa S Y; Pouwer, Frans

    2016-01-01

    PURPOSE: This study aimed to assess the longitudinal association between lifestyle factors, body mass index (BMI), and health-related quality of life (HRQoL) among colorectal cancer patients with (CRCDM+) and without diabetes (CRCDM-). METHODS: Data from a longitudinal study among CRC patients...... (including moderate-to-vigorous physical activity (MVPA), smoking and alcohol use), BMI, diabetes status, and HRQoL were assessed in the questionnaire. RESULTS: One thousand seven hundred thirty-nine (49 %) patients responded to ≥2 questionnaires, of whom 126 CRCDM+ and 789 CRCDM- patients were included...... predictors of HRQoL. Additional adjustment for comorbidity further attenuated the main effect of DM on HRQoL. CONCLUSIONS: Diabetes was not independently associated with HRQoL but deteriorated HRQoL among CRCDM+ patients seem to be explained by an unhealthier lifestyle and other comorbid conditions. Moreover...

  2. Gender Differences in Students' and Parents' Evaluative Criteria when Selecting a College

    Science.gov (United States)

    Mansfield, Phylis M.; Warwick, Jacquelyn

    2005-01-01

    Evaluation of gender differences between students and between parents based on the perceived financial, social, psychological, physical, and functional risks associated with college selection. Nineteen criteria associated with these risks were evaluated for significant gender differences as well as for their level of importance by gender in the…

  3. The Assessment of Selectivity in Different Quadrupole-Orbitrap Mass Spectrometry Acquisition Modes

    Science.gov (United States)

    Berendsen, Bjorn J. A.; Wegh, Robin S.; Meijer, Thijs; Nielen, Michel W. F.

    2015-02-01

    Selectivity of the confirmation of identity in liquid chromatography (tandem) mass spectrometry using Q-Orbitrap instrumentation was assessed using different acquisition modes based on a representative experimental data set constructed from 108 samples, including six different matrix extracts and containing over 100 analytes each. Single stage full scan, all ion fragmentation, and product ion scanning were applied. By generating reconstructed ion chromatograms using unit mass window in targeted MS2, selected reaction monitoring (SRM), regularly applied using triple-quadrupole instruments, was mimicked. This facilitated the comparison of single stage full scan, all ion fragmentation, (mimicked) SRM, and product ion scanning applying a mass window down to 1 ppm. Single factor Analysis of Variance was carried out on the variance (s2) of the mass error to determine which factors and interactions are significant parameters with respect to selectivity. We conclude that selectivity is related to the target compound (mainly the mass defect), the matrix, sample clean-up, concentration, and mass resolution. Selectivity of the different instrumental configurations was quantified by counting the number of interfering peaks observed in the chromatograms. We conclude that precursor ion selection significantly contributes to selectivity: monitoring of a single product ion at high mass accuracy with a 1 Da precursor ion window proved to be equally selective or better to monitoring two transition products in mimicked SRM. In contrast, monitoring a single fragment in all ion fragmentation mode results in significantly lower selectivity versus mimicked SRM. After a thorough inter-laboratory evaluation study, the results of this study can be used for a critical reassessment of the current identification points system and contribute to the next generation of evidence-based and robust performance criteria in residue analysis and sports doping.

  4. Simultaneous Selection for Yield and Yield Stability with Different Stability Statistics

    Directory of Open Access Journals (Sweden)

    M. taherian

    2014-08-01

    Full Text Available For decreasing the effects of Genotype ×Environment (GE interaction and having more precise selection, the yield and yield stability of selected lines should be evaluated simultaneously. YSi statistic is one of the applied methods for simultaneous selection of yield and yield stability. The objective of this study was to compare result of YSi statistic with other statistics approach such as S2i, CVi, S2di and R2i.Twenty hulless barley lines were evaluated in a randomized complete block design with three replications and in three locations (Neyshabour, Isfahan and yazd during 2007-2009 crop seasons. Results of combined ANOVA indicated significant effects for Ggenotype ×Environment × year interaction (p= 0.01. Nine lines were selected by YSi method with overall mean of 5.89 t ha-1 grain yield. Overall mean yield of selected lines using only grain yield, yield plus environmental variance (or environmental coefficient of variation and yield plus coefficient of regression and deviations from regression mean squares were 5.86, 6.01 and 5.85 t ha-1, respectively. Based to the LSD value (LSD=0.87 t ha-1, p=0.05, differences among mean yield (or different selection approaches were not significant. As a result, with using the YSi statistic (with more emphasis on stability, the cultivar selection process can be done with more confidence.

  5. Bio-economic evaluation of implementing trawl fishing gear with different selectivity

    DEFF Research Database (Denmark)

    Grønbæk Kronbak, Lone; Nielsen, J. Rasmus; Jørgensen, Ole A.

    2009-01-01

    with a baseline. The results from the evaluation are indicators for the consequences on ecological and economic levels. The results show that implementation of different selective fishing gear in the Kattegat and Skagerrak mixed trawl fisheries generally implies a trade off over time between rebuilding the stocks...... and economic loss. Moreover, the analysis shows that implementation of more selective gear is not always beneficial. (C) 2009 Elsevier Ltd. All rights reserved....

  6. Selective grazing of Temora longicornis in different stages of a Phaeocystis globosa bloom - a mesocosm study

    DEFF Research Database (Denmark)

    Koski, Marja; Dutz, Jörg; Breteler, W.C.M.K.

    2005-01-01

    Selective grazing of a calanoid copepod Temora longicornis was measured during different stages of a Phaeocystis globosa bloom, in order to reveal (1) if T longicornis feeds on single cells and/or colonies of P. globosa in the presence of alternative food sources, (2) if copepod food selection...... of alternative food sources. In contrast, feeding on single cells was never significant, and the total contribution of P globosa to carbon ingestion of T longicornis was minor. T longicornis fed most actively on the decaying colonies, whereas during the peak of the bloom copepods selected against P globosa...

  7. Improvement of Closed Crack Selectivity in Nonlinear Ultrasonic Imaging Using Fundamental Wave Amplitude Difference

    Science.gov (United States)

    Ikeuchi, Masako; Jinno, Kentaro; Ohara, Yoshikazu; Yamanaka, Kazushi

    2013-07-01

    To realize the high selectivity of closed cracks, we propose a fundamental wave amplitude difference (FAD) method based on the threshold behavior of fundamental waves caused by the contact vibration of closed cracks. This is realized by the subtraction of a fundamental array (FA) image at a small input amplitude multiplied by the amplification factor from that at a large input amplitude. The formulation clarified that FAD can selectively image closed cracks while eliminating other linear scatterers, which cannot be completely eliminated by the subharmonic wave amplitude difference (SAD) method. Furthermore, FAD was experimentally verified in a closed fatigue crack specimen using the closed-crack-imaging method of subharmonic phased array for crack evaluation (SPACE). Thus, we demonstrated that FAD is useful for achieving the higher selectivity of closed cracks against other linear scatterers than previous amplitude difference methods without filtering out the subharmonic or superharmonic waves.

  8. Plagiarism explainer for students

    OpenAIRE

    Barba, Lorena A.

    2016-01-01

    A slide deck to serve as an explainer of plagiarism in academic settings, with a personal viewpoint. For my students.Also on SpeakerDeck:https://speakerdeck.com/labarba/plagiarism-explainer-for-students(The slide viewer on SpeakerDeck is much nicer.)

  9. What explains the imbalance use of social media across different countries? A cross country analysis of presence of Twitter users tweeting scholarly publications.

    NARCIS (Netherlands)

    Zahedi, Z.

    2017-01-01

    Twitter users tweeting scholarly publications from different countries have been analysed. The aim is to explore how visible are different countries on Twitter (based on their self-assigned geo-locations obtained from altmetric.com) in comparison to their output size in the Web of Science. Some

  10. Test anxiety and performance-avoidance goals explain gender differences in SAT-V, SAT-M, and overall SAT scores.

    Science.gov (United States)

    Hannon, Brenda

    2012-11-01

    This study uses analysis of co-variance in order to determine which cognitive/learning (working memory, knowledge integration, epistemic belief of learning) or social/personality factors (test anxiety, performance-avoidance goals) might account for gender differences in SAT-V, SAT-M, and overall SAT scores. The results revealed that none of the cognitive/learning factors accounted for gender differences in SAT performance. However, the social/personality factors of test anxiety and performance-avoidance goals each separately accounted for all of the significant gender differences in SAT-V, SAT-M, and overall SAT performance. Furthermore, when the influences of both of these factors were statistically removed simultaneously, all non-significant gender differences reduced further to become trivial by Cohen's (1988) standards. Taken as a whole, these results suggest that gender differences in SAT-V, SAT-M, and overall SAT performance are a consequence of social/learning factors.

  11. Estimation of the ancestral effective population sizes of African great apes under different selection regimes.

    Science.gov (United States)

    Schrago, Carlos G

    2014-08-01

    Reliable estimates of ancestral effective population sizes are necessary to unveil the population-level phenomena that shaped the phylogeny and molecular evolution of the African great apes. Although several methods have previously been applied to infer ancestral effective population sizes, an analysis of the influence of the selective regime on the estimates of ancestral demography has not been thoroughly conducted. In this study, three independent data sets under different selective regimes were used were composed to tackle this issue. The results showed that selection had a significant impact on the estimates of ancestral effective population sizes of the African great apes. The inference of the ancestral demography of African great apes was affected by the selection regime. The effects, however, were not homogeneous along the ancestral populations of great apes. The effective population size of the ancestor of humans and chimpanzees was more impacted by the selection regime when compared to the same parameter in the ancestor of humans, chimpanzees and gorillas. Because the selection regime influenced the estimates of ancestral effective population size, it is reasonable to assume that a portion of the discrepancy found in previous studies that inferred the ancestral effective population size may be attributable to the differential action of selection on the genes sampled.

  12. What explains the imbalance use of social media across different countries? A cross country analysis of presence of Twitter users tweeting scholarly publications

    OpenAIRE

    Zahedi, Z.

    2017-01-01

    Twitter users tweeting scholarly publications from different countries have been analysed. The aim is to explore how visible are different countries on Twitter (based on their self-assigned geo-locations obtained from altmetric.com) in comparison to their output size in the Web of Science. Some indicators such as Twitter presence and activity (such as number of user’s accounts, number of tweets, and number of publications tweeted) have been analysed for each country. Finally...

  13. Age-related differences in the automatic processing of single letters: implications for selective attention.

    Science.gov (United States)

    Daffner, Kirk R; Alperin, Brittany R; Mott, Katherine K; Holcomb, Phillip J

    2014-01-22

    Older adults exhibit diminished ability to inhibit the processing of visual stimuli that are supposed to be ignored. The extent to which age-related changes in early visual processing contribute to impairments in selective attention remains to be determined. Here, 103 adults, 18-85 years of age, completed a color selective attention task in which they were asked to attend to a specified color and respond to designated target letters. An optimal approach would be to initially filter according to color and then process letter forms in the attend color to identify targets. An asymmetric N170 ERP component (larger amplitude over left posterior hemisphere sites) was used as a marker of the early automatic processing of letter forms. Young and middle-aged adults did not generate an asymmetric N170 component. In contrast, young-old and old-old adults produced a larger N170 over the left hemisphere. Furthermore, older adults generated a larger N170 to letter than nonletter stimuli over the left, but not right hemisphere. More asymmetric N170 responses predicted greater allocation of late selection resources to target letters in the ignore color, as indexed by P3b amplitude. These results suggest that unlike their younger counterparts, older adults automatically process stimuli as letters early in the selection process, when it would be more efficient to attend to color only. The inability to ignore letters early in the processing stream helps explain the age-related increase in subsequent processing of target letter forms presented in the ignore color.

  14. Grape yield to soil N-NO3- ratio can explain the different levels of biogenic amines in wine from two vineyards in the AOC Rioja (Spain)

    Science.gov (United States)

    Pérez-Álvarez, Eva Pilar; Garde-Cerdán, Teresa; Santamaría, Pilar; García-Escudero, Enrique; Peregrina, Fernando

    2014-05-01

    Plant N status may affect the grape amino acid concentration, which act as precursors in the formation of biogenic amines in wine. Biogenic amines have negative effects on human health and so they reduce the wine quality. The objective of this study was to analyze, at bloom (when the vine N demand peaks) if both the available soil N and the N concentration in the leaf could explain the amino acid concentration in the must as well as the biogenic amines in wines from AOC Rioja. Two plots with cv. Tempranillo (Vitis vinifera L.) vines grafted on R-110 rootstock were chosen: "La Grajera" (2,998 plants ha-1) and "Nájera" (2,849 plants ha-1), both plots with a traditional soil tillage management system and classified according to the American Soil Taxonomy as Typic Haloxerepts and Oxyaquic Xerorthent, respectively. Both soils had a pH higher than 7, a silty loam texture and organic matter values lower than 2%. The climatic conditions were described as semiarid Mediterranean according to the UNESCO aridity index. In each vineyard, three non-adjacent experimental plots with 3 rows of 30 vines each, were set out. No fertilizer was applied during the project. Each plot was sampled in 2009, 2010 and 2011 seasons at bloom, analyzing the available soil N-NO3- at 0-15 and 15-45 cm depth and expressing the results in kg ha-1 by means of the bulk density of soil and the coarse elements content. Also at bloom, 30 leaves per experimental plot were collected and their N concentration was analyzed. At harvest, 200 berries were taken from each plot and the amino acid content in the musts was determined by HPLC. In addition, 100 kg of grapes from each plot were taken in order to elaborate wine according to the AOC Rioja common winemaking practices. When the winemaking process was finished, the concentration of biogenic amines in the wine (histamine, methylamine, ethylamine, tyramine, putrescine, cadeverine, phenylethylamine and isoamylamine) was determined by HPLC. Our results showed

  15. Differing patterns of selection and geospatial genetic diversity within two leading Plasmodium vivax candidate vaccine antigens.

    Directory of Open Access Journals (Sweden)

    Christian M Parobek

    2014-04-01

    Full Text Available Although Plasmodium vivax is a leading cause of malaria around the world, only a handful of vivax antigens are being studied for vaccine development. Here, we investigated genetic signatures of selection and geospatial genetic diversity of two leading vivax vaccine antigens--Plasmodium vivax merozoite surface protein 1 (pvmsp-1 and Plasmodium vivax circumsporozoite protein (pvcsp. Using scalable next-generation sequencing, we deep-sequenced amplicons of the 42 kDa region of pvmsp-1 (n = 44 and the complete gene of pvcsp (n = 47 from Cambodian isolates. These sequences were then compared with global parasite populations obtained from GenBank. Using a combination of statistical and phylogenetic methods to assess for selection and population structure, we found strong evidence of balancing selection in the 42 kDa region of pvmsp-1, which varied significantly over the length of the gene, consistent with immune-mediated selection. In pvcsp, the highly variable central repeat region also showed patterns consistent with immune selection, which were lacking outside the repeat. The patterns of selection seen in both genes differed from their P. falciparum orthologs. In addition, we found that, similar to merozoite antigens from P. falciparum malaria, genetic diversity of pvmsp-1 sequences showed no geographic clustering, while the non-merozoite antigen, pvcsp, showed strong geographic clustering. These findings suggest that while immune selection may act on both vivax vaccine candidate antigens, the geographic distribution of genetic variability differs greatly between these two genes. The selective forces driving this diversification could lead to antigen escape and vaccine failure. Better understanding the geographic distribution of genetic variability in vaccine candidate antigens will be key to designing and implementing efficacious vaccines.

  16. Explaining consumer brand-related activities on social media : An investigation of the different roles of self-expression and socializing motivations

    NARCIS (Netherlands)

    de Vries, Lisette; Peluso, A.M.; Romani, S.; Leeflang, Pieter; Marcati, A.

    2017-01-01

    People undertake various brand-related activities on social media that differ in levels of engagement. Companies, however, want to know how to motivate consumers to become involved in the relatively more engaging activities, as such activities are more likely to lead to increased sales. In this

  17. Do Differences in School's Instruction Time Explain International Achievement Gaps in Maths, Science and Language? Evidence from Developed and Developing Countries. CEE DP 118

    Science.gov (United States)

    Lavy, Victor

    2010-01-01

    There are large differences across countries in instructional time in public schooling institutions. For example, among European countries such as Belgium, France and Greece, pupils aged 15 have an average of over a thousand hours per year of total compulsory classroom instruction while in England, Luxembourg and Sweden the average is only 750…

  18. An Initial Evaluation of the Role of Emotion and Impulsivity in Explaining Racial/Ethnic Differences in the Use of Corporal Punishment

    Science.gov (United States)

    Lorber, Michael F.; O'Leary, Susan G.; Slep, Amy M. Smith

    2011-01-01

    The authors sought to provide an initial evaluation of the hypothesis that corporal punishment is less strongly associated with parental emotion and impulsivity among African American ("Black") in contrast to European American ("White") parents. White-Latino and Black-Latino differences in corporal punishment, emotion, and impulsivity were…

  19. Differences in nonspecific bronchial responsiveness between patients with asthma and patients with rhinitis are not explained by type and degree of inhalant allergy

    NARCIS (Netherlands)

    Witteman, A. M.; Sjamsoedin, D. H.; Jansen, H. M.; van der Zee, J. S.

    1997-01-01

    Patients with allergic asthma have higher levels of nonspecific bronchial responsiveness than patients with allergic rhinitis. The aim of the study was to investigate whether this is caused by differences in the degree of allergy to inhalant allergens between asthmatics and rhinitics. Therefore,

  20. Interspecific differences in habitat selection of syngnathids in the Ria Formosa lagoon, Portugal

    Science.gov (United States)

    Müller, Carolin; Erzini, Karim

    2017-04-01

    Interspecific patterns of local population abundances and differences in habitat preference of two seagrass resident pipefish species of the genus Syngnathus were investigated in a semi-protected lagoon system in Southern Portugal. The results of the combination of field surveys across different seagrass meadows and laboratory habitat choice experiments between May and September 2014 demonstrate that the pipefish population structure in a single-species meadow composed of Zostera noltei differed significantly from the ones in a single-species meadow of Cymodocea nodosa and a mixed meadow of both seagrasses. In addition, the two most abundant pipefish species, Syngnathus typhle and Syngnathus abaster, showed interspecific and intersexual differences in habitat selection both on a macro- and a microhabitat scale in laboratory experiments. The study suggests that in addition to the investigated structural characteristics of sea grasses (i.e. shoot length and density), other factors such as flow velocity may influence habitat selection of syngnathids.

  1. Selection of different types of physics problems as a tool to guide cognitive processes

    Directory of Open Access Journals (Sweden)

    María Elena Truyol

    2011-03-01

    Full Text Available In this paper we use different types of word problems to study characteristics of problem-solving processes, understood as a modeling process. We work with a model of comprehension and we propose a classification for word problems around the idea of scientific model. An experimental set of two types of problems is constructed in relation to the explicit presence of the scientific model in the statement: undefined and well-defined. Subjects, two academics, were audio and video-taped during a problem-solving interview. The analysis of the interviews supports the hypothesis that differences in the statements generate different problem-solving processes. These differences seem to be associated with conceptual modeling skills. These results highlight some significant issues to be considered by teachers when selecting problems. We discuss criteria to guide the selection of one or another type of statement.

  2. Between-mode-differences in the value of travel time: Self-selection or strategic behaviour?

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Hjorth, Katrine; Lyk-Jensen, Stéphanie Vincent

    2010-01-01

    Using stated preference survey data, we measure the value of travel time for several transport modes. We find, like many before us, that the value of travel time varies across modes in the opposite direction of what would be the consequence of differences in comfort. We examine three candidate...... causes for the observed differences: Comfort effects, self-selection and strategic behaviour of respondents. Using experiments with both the current and an alternative mode we find that the differences in the value of travel time are consistent with self-selection and comfort effects. Moreover......, respondents having bus as the current or the alternative mode seem not to value comfort differently across modes. Strategic behaviour seems to play no role....

  3. Are there differences in selective attention and conflict resolution between monolingual and bilingual children?

    NARCIS (Netherlands)

    Mondt, K.; Noort, M.W.M.L. van den; Balériaux, D.; Bosch, M.P.C.; Hadzibeganovic, T.; Denolin, V.; Craen, P. van de

    2009-01-01

    Objectives Possible differences in selective attention and conflict resolution between monolingual and bilingual children were tested in an fMRI study. Methods An adopted version of the Stroop task was conducted on 19 monolingual- and bilingual (French/Dutch) children with a mean age of 8.9 years in

  4. Criterion-related validity op Dutch police-selection measures and differences between ethnic groups.

    NARCIS (Netherlands)

    L.A.L. de Meijer (Lonneke); M.Ph. Born (Marise); G. Terlouw (Gert); H.T. van der Molen (Henk)

    2008-01-01

    textabstractThis study investigated the criterion-related validity of cognitive ability as well as non-cognitive ability measures and differences between ethnic majority (N = 2,365) and minority applicants (N = 682) in Dutch police officer selection. Findings confirmed the relatively low predictive

  5. Invasive ecosystem engineer selects for different phenotypes of an associated native species.

    Science.gov (United States)

    Wright, Jeffrey T; Gribben, Paul E; Byers, James E; Monro, Keyne

    2012-06-01

    Invasive habitat-forming ecosystem engineers modify the abiotic environment and thus represent a major perturbation to many ecosystems. Because native species often persist in these invaded habitats but have no shared history with the ecosystem engineer, the engineer may impose novel selective pressure on native species. In this study, we used a phenotypic selection framework to determine whether an invasive habitat-forming ecosystem engineer (the seaweed Caulerpa taxifolia) selects for different phenotypes of a common co-occurring native species (the bivalve Anadara trapezia). Compared to unvegetated habitat, Caulerpa habitat has lower water flow, lower dissolved oxygen, and sediments are more silty and anoxic. We determined the performance consequences of variation in key functional traits that may be affected by these abiotic changes (shell morphology, gill mass, and palp mass) for Anadara transplanted into Caulerpa and unvegetated habitat. Both linear and nonlinear performance gradients in Anadara differed between habitats, and these gradients were stronger in Caulerpa compared to unvegetated sediment. Moreover, in Caulerpa alternate phenotypes performed well, and these phenotypes were different from the dominant phenotype in unvegetated sediment. By demonstrating that phenotype-performance gradients differ between habitats, we have highlighted a role for Caulerpa as an agent of selection on native species.

  6. Phenotypic Changes in Different Spinach Varieties Grown and Selected under Organic Conditions

    Directory of Open Access Journals (Sweden)

    Nicolas Schermann

    2011-09-01

    Full Text Available Organic and low-input agriculture needs flexible varieties that can buffer environmental stress and adapt to the needs of farmers. We implemented an experiment to investigate the evolutionary capacities of a sample of spinach (Spinacia oleracea L. population varieties for a number of phenotypic traits. Three farmers cultivated, selected and multiplied one or several populations over two years on their farms. The third year, the versions of the varieties cultivated and selected by the different farmers were compared to the original seed lots they had been given. After two cycles of cultivation and on-farm mass selection, all the observed varieties showed significant phenotypic changes (differences between the original version and the version cultivated by farmers for morphological and phenological traits. When the divergence among versions within varieties was studied, the results show that the varieties conserved their identity, except for one variety, which evolved in such a way that it may now be considered two different varieties. The heterogeneity of the population varieties was assessed in comparison with a commercial F1 hybrid used as control, and we found no specific differences in phenotypic diversity between the hybrid and population varieties. The phenotypic changes shown by the population varieties in response to on-farm cultivation and selection could be useful for the development of specific adaptation. These results call into question the current European seed legislation and the requirements of phenotypic stability for conservation varieties.

  7. Food selection preference of different ages and sizes of black tiger ...

    African Journals Online (AJOL)

    The investigation of food and food selection preferred by different sizes (PL15 to adult) of black tiger shrimp, Penaeus monodon Fabricius 1798, was carried out in tropical aquaculture ponds. Post larvae (15.2 ± 3.5 mm) and juveniles (65.2 ± 5.9 mm) foregut contains detritus (unidentified materials) followed by diatoms ...

  8. Selective absorption of water from different oil–water emulsions with ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 30; Issue 4. Selective absorption of water from different oil–water emulsions with Psy-cl-poly(AAm) synthesized using irradiation copolymerization method. B S Kaith Kiran Kumar. Polymers Volume 30 Issue 4 August 2007 pp 387-391 ...

  9. Reporting explained variance

    Science.gov (United States)

    Good, Ron; Fletcher, Harold J.

    The importance of reporting explained variance (sometimes referred to as magnitude of effects) in ANOVA designs is discussed in this paper. Explained variance is an estimate of the strength of the relationship between treatment (or other factors such as sex, grade level, etc.) and dependent variables of interest to the researcher(s). Three methods that can be used to obtain estimates of explained variance in ANOVA designs are described and applied to 16 studies that were reported in recent volumes of this journal. The results show that, while in most studies the treatment accounts for a relatively small proportion of the variance in dependent variable scores., in., some studies the magnitude of the treatment effect is respectable. The authors recommend that researchers in science education report explained variance in addition to the commonly reported tests of significance, since the latter are inadequate as the sole basis for making decisions about the practical importance of factors of interest to science education researchers.

  10. Occupational segregation, selection effects and gender wage differences: evidence from urban Colombia

    Directory of Open Access Journals (Sweden)

    Jairo Guillermo Isaza Castro

    2014-06-01

    Full Text Available This paper assesses the effects of occupational segregation on the gender wage gap in urban Colombia between 1986 and 2000. The empirical methodology involves a two step procedure where by the occupational distributions ofworkers by gender aremodelled using a multinomial logit model in the first stage. In the second stage, the multinomial logit estimates are used not only to derive a counterfactual occupational distribution of women in the absence of workplace discrimination but also to correct for selectivity bias in thewage equations for each occupational category using the procedure suggested by Lee (1983. Besides the explained and unexplained components in conventional decompositions of the gender wage gap, this methodology differentiates between the justified and unjustified effects of the gender allocation ofworkers across occupational categories. The results for urban Colombia indicate that controlling for selectivity bias at the occupational category level is found to be relevant in all years reviewed in this study. They also suggest that a changing composition of the female labour supply in terms of un observables (i.e., ability and motivation is playing a role in the dramatic reduction of the observed wage gap.

  11. What explains the differences in income and labour utilisation and drives labour and economic growth in Europe? A GDP accounting perspective

    OpenAIRE

    Gilles Mourre

    2009-01-01

    The paper decomposes GDP both in terms of level per capita and growth rate, so as to identify the sources of income differences and of economic growth for all EU27 member states. This accounting approach has multiple advantages, although a number of substantial caveats should be borne in mind when interpreting the results. In particular, the detailed accounting approach helps distinguish exogenous from policy-influenced growth drivers. The combination of lower per-hour productivity and lower ...

  12. Variations in the morphology of wood structure can explain why hardwood species of similar density have very different resistances to impact and compressive loading.

    Science.gov (United States)

    Hepworth, David G; Vincent, J F V; Stringer, G; Jeronimidis, G

    2002-02-15

    A clear relationship has been established between the impact resistance and density of softwoods. However, there are hardwood species that have the same density but very different impact resistance. Softwoods are largely composed of tracheid cells (30-50 microm across); hardwoods have smaller fibre cells and also contain vessels (50-500 microm across). We examined white oak, beech, hickory and spruce. Compressive deformation was identified as the main mechanism for energy absorption in the type of impact test used. The disparate size of different wood cells in the hardwoods results in heterogeneous compressive deformation. During compression, large vessels cause smaller surrounding cells to be deformed more than in regions without vessels, increasing the energy absorbed. However, vessels that are too close together initiate kink banding at low loads and less energy is absorbed. The different morphologies of hardwoods are probably responsible for the variation in impact resistance between species of similar density. Drilling small holes along the grain of spruce, which naturally lacks vessels, mimicked the effect of vessels and did not reduce the energy-absorbing capabilities of the wood, despite the density being reduced. These findings could be used to increase the energy-absorbing capacity of synthetic foam materials.

  13. Measures of the ovaries and uterus during development of gilts selected for differences in uterine capacity.

    Science.gov (United States)

    Lents, C A; Cushman, R A; Freking, B A

    2014-06-01

    Direct selection for uterine capacity (UC) increased the number of live pigs born. A method to indirectly estimate UC in developing gilts is needed for this trait to be incorporated into commercial selection strategies. We tested the hypothesis that selection for UC alters phenotypic characteristics of the reproductive tract of prepubertal gilts and that these changes could be estimated in live animals using transrectal ultrasound (TRU). Gilts from lines selected for UC and a randomly selected control (CO) line were submitted for TRU at 130, 150, or 170 d of age and harvested 24 h later (n = 10 gilts/line per age). Diameter of the uterine horn was measured (2 to 4 measurements per animal) at TRU. At harvest, measurements of the ovary (height, width, length, weight, and number of visible follicles >1 mm) and uterine horn (weight, length, diameter, and endometrial diameter) were taken. There was no line × age interaction for any of the traits. All ovarian traits increased (P gilts, but the number of visible follicles did not differ. The UC gilts had increased (P gilts. Diameter of the uterine horn and the endometrium were greater (P gilts than for CO gilts. Uterine horn diameter measured with TRU was not affected by age or line and was not highly correlated with any of the measured traits. Selection for increased UC results in larger ovaries and uterine horns, but TRU was not useful for estimating these traits in gilts of the age studied.

  14. Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico.

    Science.gov (United States)

    Kraft, Kraig H; de Jesús Luna-Ruíz, José; Gepts, Paul

    2010-12-01

    Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico. The process of selecting and saving seed is the most basic and oldest of agricultural practices. In today's modern and highly capital-intensive agriculture, seeds are often treated like another chemical input. This study sought to examine seed selection and saving practices among chile farmers in Aguascalientes, Mexico, where both industrial and traditional agriculture are practiced. We observed a clear division among farmers who plant chile peppers commercially. Sixty-eight chile pepper farmers were surveyed in order to document seed selection and saving practices. Fifteen respondents (22%) planted chile peppers destined for the fresh market and all utilized purchased commercial seed of F1 hybrid varieties. Fifty-three farmers (78%) planted chiles to be dried and either saved their own or purchased seeds that others had saved and selected. Farmers who saved their own seed sought to maintain an ideotype, rather than directionally select for certain traits, much like Cleveland et al. (2000) chronicled in central Mexican maize farmers. Farmers would benefit from a participatory plant-breeding program in order to maintain productive seed stock for the continued cultivation of dried chile pepper in the state.

  15. First selection, then influence: Developmental differences in friendship dynamics regarding academic achievement.

    Science.gov (United States)

    Gremmen, Mariola Claudia; Dijkstra, Jan Kornelis; Steglich, Christian; Veenstra, René

    2017-07-01

    This study concerns peer selection and influence dynamics in early adolescents' friendships regarding academic achievement. Using longitudinal social network analysis (RSiena), both selection and influence processes were investigated for students' average grades and their cluster-specific grades (i.e., language, exact, and social cluster). Data were derived from the SNARE (Social Network Analysis of Risk behavior in Early adolescence) study, using 6 waves (N = 601; Mage = 12.66, 48.9% boys at first wave). Results showed developmental differences between the first and second year of secondary school (seventh and eighth grade). Whereas selection processes were found in the first year on students' cluster-specific grades, influence processes were found in the second year, on both students' average and cluster-specific grades. These results suggest that students initially tend to select friends on the basis of similar cluster-based grades (first year), showing that similarity in achievement is attractive for friendships. Especially for low-achieving students, similar-achieving students were highly attractive as friends, whereas they were mostly avoided by high-achieving students. Influence processes on academic achievement take place later on (second year), when students know each other better, indicating that students' grades become more similar over time in response to their connectedness. Concluding, this study shows the importance of developmental differences and specific school subjects for understanding peer selection and influence processes in adolescents' academic achievement. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. Similar recent selection criteria associated with different behavioural effects in two dog breeds.

    Science.gov (United States)

    Sundman, A-S; Johnsson, M; Wright, D; Jensen, P

    2016-11-01

    Selection during the last decades has split some established dog breeds into morphologically and behaviourally divergent types. These breed splits are interesting models for behaviour genetics since selection has often been for few and well-defined behavioural traits. The aim of this study was to explore behavioural differences between selection lines in golden and Labrador retriever, in both of which a split between a common type (pet and conformation) and a field type (hunting) has occurred. We hypothesized that the behavioural profiles of the types would be similar in both breeds. Pedigree data and results from a standardized behavioural test from 902 goldens (698 common and 204 field) and 1672 Labradors (1023 and 649) were analysed. Principal component analysis revealed six behavioural components: curiosity, play interest, chase proneness, social curiosity, social greeting and threat display. Breed and type affected all components, but interestingly there was an interaction between breed and type for most components. For example, in Labradors the common type had higher curiosity than the field type (F1,1668 = 18.359; P < 0.001), while the opposite was found in goldens (F1,897 = 65.201; P < 0.001). Heritability estimates showed considerable genetic contributions to the behavioural variations in both breeds, but different heritabilities between the types within breeds was also found, suggesting different selection pressures. In conclusion, in spite of similar genetic origin and similar recent selection criteria, types behave differently in the breeds. This suggests that the genetic architecture related to behaviour differs between the breeds. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  17. A mechanistic PK/PD model for two anti-IL13 antibodies explains the difference in total IL-13 accumulation observed in clinical studies.

    Science.gov (United States)

    Tiwari, Abhinav; Kasaian, Marion; Heatherington, Anne C; Jones, Hannah M; Hua, Fei

    2016-07-01

    IMA-638 and IMA-026 are humanized IgG1 monoclonal antibodies (mAbs) that target non-overlapping epitopes of IL-13. Separate first-in-human single ascending dose studies were conducted for each mAb. These studies had similar study designs, but mild to moderate asthmatics were recruited for the IMA-638 study and healthy subjects were recruited for the IMA-026 study. IMA-638 and IMA-026 showed similar pharmacokinetic (PK) profiles, but very different total IL-13 (free and drug bound IL-13) profiles; free IL13 was not measured. IMA-026 treatment induced a dose-dependent accumulation of total IL-13, while IMA-638 treatment led to a much smaller accumulation without any clear dose-response. To understand the differences between the two total IL-13 profiles and to predict the free IL-13 profiles for each mAb treatment, a mechanistic PK/pharmacodynamic model was developed. PK-related parameters were first fit to the mean PK profiles of each mAb separately; thereafter, the target-related parameters were fit to both total IL-13 profiles simultaneously. The IL-13 degradation rate was assumed to be the same for asthma patients and healthy subjects. The model suggests that an approximately 100× faster elimination of IL-13-IMA-638 complex than IL-13-IMA-026 complex could be responsible for the differences observed in total IL-13 profiles for the two mAbs. Furthermore, the model predicts that IMA-638 administration results in greater and more prolonged free IL-13 inhibition than equivalent dosing of IMA-026 despite similar binding KD and PK profile. In conclusion, joint modeling of two similar molecules provided mechanistic insight that the elimination rate of mAb-target complex can regulate the degree of free target inhibition.

  18. Oxidative costs of reproduction in mouse strains selected for different levels of food intake and which differ in reproductive performance

    DEFF Research Database (Denmark)

    Jothery, Aqeel H. Al; Vaanholt, Lobke M.; Mody, Nimesh

    2016-01-01

    Oxidative damage caused by reactive oxygen species has been hypothesised to underpin the trade-off between reproduction and somatic maintenance, i.e., the life-history-oxidative stress theory. Previous tests of this hypothesis have proved equivocal, and it has been suggested that the variation...... in responses may be related to the tissues measured. Here, we measured oxidative damage (protein carbonyls, 8-OHdG) and antioxidant protection (enzymatic antioxidant activity and serum antioxidant capacity) in multiple tissues of reproductive (R) and non-reproductive (N) mice from two mouse strains selectively...... bred for high (H) or low (L) food intake, which differ in their reproductive performance, i.e., H mice have increased milk energy output (MEO) and wean larger pups. Levels of oxidative damage were unchanged (liver) or reduced (brain and serum) in R versus N mice, and no differences in multiple measures...

  19. Socio-economic factors explain differences in public health-related variables among women in Bangladesh: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Kraemer Alexander

    2008-07-01

    Full Text Available Abstract Background Worldwide one billion people are living in slum communities and experts projected that this number would double by 2030. Slum populations, which are increasing at an alarming rate in Bangladesh mainly due to rural-urban migration, are often neglected and characterized by poverty, poor housing, overcrowding, poor environment, and high prevalence of communicable diseases. Unfortunately, comparisons between women living in slums and those not living in slums are very limited in Bangladesh. The objectives of the study were to examine the association of living in slums (dichotomized as slum versus non-slum with selected public health-related variables among women, first without adjusting for the influence of other factors and then in the presence of socio-economic variables. Methods Secondary data was used in this study. 120 women living in slums (as cases and 480 age-matched women living in other areas (as controls were extracted from the Bangladesh Demographic and Health Survey 2004. Many socio-economic and demographic variables were analysed. SPSS was used to perform simple as well as multiple analyses. P-values based on t-test and Wald test were also reported to show the significance level. Results Unadjusted results indicated that a significantly higher percent of women living in slums came from country side, had a poorer status by household characteristics, had less access to mass media, and had less education than women not living in slums. Mean BMI, knowledge of AIDS indicated by ever heard about AIDS, knowledge of avoiding AIDS by condom use, receiving adequate antenatal visits (4 or more during the last pregnancy, and safe delivery practices assisted by skilled sources were significantly lower among women living in slums than those women living in other areas. However, all the unadjusted significant associations with the variable slum were greatly attenuated and became insignificant (expect safe delivery practices when

  20. Socio-economic factors explain differences in public health-related variables among women in Bangladesh: a cross-sectional study.

    Science.gov (United States)

    Khan, Md Mobarak H; Kraemer, Alexander

    2008-07-23

    Worldwide one billion people are living in slum communities and experts projected that this number would double by 2030. Slum populations, which are increasing at an alarming rate in Bangladesh mainly due to rural-urban migration, are often neglected and characterized by poverty, poor housing, overcrowding, poor environment, and high prevalence of communicable diseases. Unfortunately, comparisons between women living in slums and those not living in slums are very limited in Bangladesh. The objectives of the study were to examine the association of living in slums (dichotomized as slum versus non-slum) with selected public health-related variables among women, first without adjusting for the influence of other factors and then in the presence of socio-economic variables. Secondary data was used in this study. 120 women living in slums (as cases) and 480 age-matched women living in other areas (as controls) were extracted from the Bangladesh Demographic and Health Survey 2004. Many socio-economic and demographic variables were analysed. SPSS was used to perform simple as well as multiple analyses. P-values based on t-test and Wald test were also reported to show the significance level. Unadjusted results indicated that a significantly higher percent of women living in slums came from country side, had a poorer status by household characteristics, had less access to mass media, and had less education than women not living in slums. Mean BMI, knowledge of AIDS indicated by ever heard about AIDS, knowledge of avoiding AIDS by condom use, receiving adequate antenatal visits (4 or more) during the last pregnancy, and safe delivery practices assisted by skilled sources were significantly lower among women living in slums than those women living in other areas. However, all the unadjusted significant associations with the variable slum were greatly attenuated and became insignificant (expect safe delivery practices) when some socio-economic variables namely childhood place

  1. A comparison of different dimensionality reduction and feature selection methods for single trial ERP detection.

    Science.gov (United States)

    Lan, Tian; Erdogmus, Deniz; Black, Lois; Van Santen, Jan

    2010-01-01

    Dimensionality reduction and feature selection is an important aspect of electroencephalography based event related potential detection systems such as brain computer interfaces. In our study, a predefined sequence of letters was presented to subjects in a Rapid Serial Visual Presentation (RSVP) paradigm. EEG data were collected and analyzed offline. A linear discriminant analysis (LDA) classifier was designed as the ERP (Event Related Potential) detector for its simplicity. Different dimensionality reduction and feature selection methods were applied and compared in a greedy wrapper framework. Experimental results showed that PCA with the first 10 principal components for each channel performed best and could be used in both online and offline systems.

  2. Effect of different oral oxytetracycline treatment regimes on selection of antimicrobial resistant coliforms in nursery pigs

    DEFF Research Database (Denmark)

    Fresno, Ana Herrero; Zachariasen, Camilla; Norholm, Nanna

    2017-01-01

    A major concern derived from using antimicrobials in pig production is the development of resistance. This study aimed to assess the impact of selected combinations of oral dose and duration of treatment with oxytetracycline (OTC) on selection of tetracycline resistant (TET-R) coliforms recovered......, under field conditions. Statistical modeling was applied to analyze trends in the proportion of TET-R coliforms. In the experimental study, no statistical difference in proportion of TET-R coliforms was observed between treatments at the end of the trial (day 18) and compared to day 0. In the field...

  3. Comparing different protocols of temperature selection in the parallel tempering method.

    Science.gov (United States)

    Fiore, Carlos E

    2011-09-21

    Parallel tempering Monte Carlo simulations have been applied to a variety of systems presenting rugged free-energy landscapes. Despite this, its efficiency depends strongly on the temperature set. With this query in mind, we present a comparative study among different temperature selection schemes in three lattice-gas models. We focus our attention in the constant entropy method (CEM), proposed by Sabo et al. In the CEM, the temperature is chosen by the fixed difference of entropy between adjacent replicas. We consider a method to determine the entropy which avoids numerical integrations of the specific heat and other thermodynamic quantities. Different analyses for first- and second-order phase transitions have been undertaken, revealing that the CEM may be an useful criterion for selecting the temperatures in the parallel tempering.

  4. Mental Well-Being Differences in Cohabitation and Marriage: The Role of Childhood Selection.

    Science.gov (United States)

    Perelli-Harris, Brienna; Styrc, Marta

    2018-02-01

    Prior studies have found that marriage benefits well-being, but cohabitation may provide similar benefits. An analysis of the British Cohort Study 1970, a prospective survey following respondents to age 42, examines whether partnerships in general, and marriage in particular, influence mental well-being in midlife. Propensity score matching indicates whether childhood characteristics are a sufficient source of selection to eliminate differences in well-being between those living with and without a partner and those cohabitating and married. The results indicate that matching on childhood characteristics does not eliminate advantages to living with a partner; however, matching eliminates differences between marriage and cohabitation for men and women more likely to marry. On the other hand, marriage may provide benefits to women less likely to marry unless they have shared children and are in long-lasting partnerships. Hence, childhood selection attenuates differences between cohabitation and marriage, except for women less likely to marry.

  5. Does Financial Hardship Explain Differences Between Belgian and South African Unemployed Regarding Experiences of Unemployment, Employment Commitment, and Job Search Behaviour?

    Directory of Open Access Journals (Sweden)

    Wouter Vleugels

    2013-06-01

    Full Text Available The purpose of this study was to investigate whether Belgian and South African unemployed differed regarding three psychological dimensions of unemployment: affect (experiences of unemployment, attitudes (employment commitment, and behaviour (job search intensity. Moreover, we expected country of residence to indirectly influence unemployed people's experiences, employment commitment, and job search intensity via financial hardship. A cross-sectional survey design was used to test our hypotheses. Data were sampled from unemployed people in the Brussels area in Belgium ('N' = 305, and the Potchefstroom area in South Africa ('N' = 381. The results indicated that, compared to the Belgian unemployed, the South African unemployed experienced their unemployment as more negative, were more committed towards employment and more intensively searched for work. Moreover, country of residence indirectly influenced unemployed people's experiences, employment commitment, and job search intensity via financial hardship. Some policy recommendations are suggested.

  6. Structural differences between rye and wheat breads but not total fiber content may explain the lower postprandial insulin response to rye bread

    DEFF Research Database (Denmark)

    Juntunen, Katri S; Laaksonen, David E; Autio, Karin

    2003-01-01

    -fiber rye bread; each bread provided 50 g available carbohydrate and was served with breakfast. Plasma glucose, insulin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and serum C-peptide were measured in fasting and 8 postprandial blood samples. In vitro starch hydrolysis......BACKGROUND: Rye bread has a beneficial effect on the postprandial insulin response in healthy subjects. The role of rye fiber in insulin and glucose metabolism is not known. OBJECTIVE: The aim of the study was to determine the effect of the content of rye fiber in rye breads on postprandial insulin...... and the microscopic structure of the breads were also determined. RESULTS: Postprandial insulin, glucose-dependent insulinotropic polypeptide, and C-peptide responses to the rye breads were significantly lower than the response to the control; no significant differences in insulin and C-peptide responses to the rye...

  7. The effect of thermodynamic properties of solvent mixtures explains the difference between methanol and ethanol in C.antarctica lipase B catalyzed alcoholysis.

    Science.gov (United States)

    Sasso, Francesco; Kulschewski, Tobias; Secundo, Francesco; Lotti, Marina; Pleiss, Jürgen

    2015-11-20

    Kinetic modelling, molecular modelling, and experimental determination of the initial reaction velocity of lipase-catalyzed alcoholysis were combined to study the effect of the alcohol substrate to catalytic activity. The model system consisted of methanol or ethanol at varying concentrations, vinyl acetate as ester substrate 15.2% (v/v), toluene as organic solvent, water at a controlled thermodynamic activity of 0.09, and C. antarctica lipase B as enzyme. For both alcohol substrates, the initial reaction velocity increased sharply at low concentrations and reached a maximum at 0.7% (v/v) for methanol and 2% (v/v) for ethanol. For higher concentrations, the reaction rate decreased to a level of 74% and 60% of the peak value, respectively, due to substrate inhibition. The concentration dependency was described by a kinetic model, including a ping-pong bi-bi mechanism and competitive inhibition by the alcohol, and confirmed previous observations that methanol is more efficiently inhibiting the enzyme than ethanol. However, if the initial reaction velocity was expressed in terms of thermodynamic activity of the two alcohol substrates, the maximum of initial reaction velocity was similar for methanol (a MeOH(max)=0.19) and ethanol (a EtOH(max)=0.21). This was confirmed by molecular modelling which resulted in similar KM (0.22 and 0.19) and Ki values (0.44 and 0.49) for methanol and ethanol, respectively, if expressed in thermodynamic activities. Thus, the experimentally observed difference between methanol and ethanol is not due to differences in interaction with the enzyme but is a consequence of the thermodynamics of the substrate-solvent mixture. For low concentrations in toluene, the activity coefficient of methanol is 40% higher than the activity coefficient of ethanol (γ MeOH=8.5, γ EtOH=6.1). Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Sexual selection and sex differences in the prevalence of childhood externalizing and adolescent internalizing disorders.

    Science.gov (United States)

    Martel, Michelle M

    2013-11-01

    Despite the well-established sex difference in prevalence of many childhood and adolescent psychopathological conditions, no integrative metatheory of sex differences in psychopathology exists. This review attempts to provide a metatheoretical framework to guide empirical examination of sex differences in prevalence of childhood-onset "externalizing" and adolescent-onset "internalizing" disorders, based on sexual selection evolutionary theory. Sexual selection theory suggests important between-sex differences in markers, mechanisms, etiology, and developmental timing of risk and resilience relevant to psychopathology. Namely, sexual selection theory hypothesizes that disinhibition and sensation-seeking may be important proximate risk markers for childhood-onset externalizing disorders in males. The theory suggests that these male-biased markers may be a product of their higher exposure to prenatal testosterone, which makes them more susceptible to prenatal stressors with downstream effects on dopaminergic neurotransmission, especially for those with genetic alleles associated with lower dopaminergic function. In contrast, sexual selection theory hypothesizes that negative emotionality, empathy, and cognitive rumination may be important proximate risk markers for adolescent-onset internalizing disorders in females. The theory suggests that these markers are propagated by rapidly rising levels of estradiol at puberty that interact with cortisol and oxytocin. These hormones exert downstream effects on the serotonergic system in such a way as to increase females' sensitivity to interpersonal stressors particularly at puberty and especially for those with lower functional serotonergic activity. Such a metatheory can help integrate prior ideas about sex differences and can also generate new predictions of sex differences in markers, etiology, mechanisms, and developmental timing of common forms of psychopathology. © 2013 American Psychological Association

  9. Adaptive Laboratory Evolution of Antibiotic Resistance Using Different Selection Regimes Lead to Similar Phenotypes and Genotypes

    DEFF Research Database (Denmark)

    Jahn, Leonie Johanna; Munck, Christian; Ellabaan, Mostafa M Hashim

    2017-01-01

    Antibiotic resistance is a global threat to human health, wherefore it is crucial to study the mechanisms of antibiotic resistance as well as its emergence and dissemination. One way to analyze the acquisition of de novo mutations conferring antibiotic resistance is adaptive laboratory evolution....... However, various evolution methods exist that utilize different population sizes, selection strengths, and bottlenecks. While evolution in increasing drug gradients guarantees high-level antibiotic resistance promising to identify the most potent resistance conferring mutations, other selection regimes...... are simpler to implement and therefore allow higher throughput. The specific regimen of adaptive evolution may have a profound impact on the adapted cell state. Indeed, substantial effects of the selection regime on the resulting geno- and phenotypes have been reported in the literature. In this study we...

  10. Explaining human recreational use of 'pesticides': The neurotoxin regulation model of substance use vs. the hijack model and implications for age and sex differences in drug consumption

    Directory of Open Access Journals (Sweden)

    Edward H Hagen

    2013-11-01

    Full Text Available Most globally popular drugs are plant neurotoxins or their close chemical analogs. These compounds evolved to deter, not reward or reinforce, consumption. Moreover, they reliably activate virtually all toxin defense mechanisms, and are thus correctly identified by human neurophysiology as toxins. Acute drug toxicity must therefore play a more central role in drug use theory. We accordingly challenge the popular idea that the rewarding and reinforcing properties of drugs "hijack" the brain, and propose instead that the brain evolved to carefully regulate neurotoxin consumption to minimize fitness costs and maximize fitness benefits. This perspective provides a compelling explanation for the dramatic changes in substance use that occur during the transition from childhood to adulthood, and for pervasive sex differences in substance use: because nicotine and many other plant neurotoxins are teratogenic, children, and to a lesser extent women of childbearing age, evolved to avoid ingesting them. However, during the course of human evolution many adolescents and adults reaped net benefits from regulated intake of plant neurotoxins.

  11. Different alternative splicing patterns are subject to opposite selection pressure for protein reading frame preservation

    Directory of Open Access Journals (Sweden)

    Chuang Trees-Juen

    2007-09-01

    Full Text Available Abstract Background Alternative splicing (AS has been regarded capable of altering selection pressure on protein subsequences. Particularly, the frequency of reading frame preservation (FRFP, as a measure of selection pressure, has been reported to be higher in alternatively spliced exons (ASEs than in constitutively spliced exons (CSEs. However, recently it has been reported that different ASE types – simple and complex ASEs – may be subject to opposite selection forces. Therefore, it is necessary to re-evaluate the evolutionary effects of such splicing patterns on frame preservation. Results Here we show that simple and complex ASEs, respectively, have higher and lower FRFPs than CSEs. Since complex ASEs may alter the ends of their flanking exons, the selection pressure on frame preservation is likely relaxed in this ASE type. Furthermore, conservation of the ASE/CSE splicing pattern increases the FRFPs of simple ASEs but decreases those of complex ASEs. Contrary to the well-recognized concept of strong selection pressure on conserved ASEs for protein reading frame preservation, our results show that conserved complex ASEs are relaxed from such pressure and the frame-disrupting effect caused by the insertion of complex ASEs can be offset by compensatory changes in their flanking exons. Conclusion In this study, we find that simple and complex ASEs undergo opposite selection pressure for protein reading frame preservation, with CSEs in-between. Simple ASEs have much higher FRFPs than complex ones. We further find that the FRFPs of complex ASEs coupled with flanking exons are close to those of simple ASEs, indicating that neighboring exons of an ASE may evolve in a coordinated way to avoid protein dysfunction. Therefore, we suggest that evolutionary analyses of AS should take into consideration the effects of different splicing patterns and the joint effects of multiple AS events.

  12. Why mammalian lineages respond differently to sexual selection: metabolic rate constrains the evolution of sperm size.

    Science.gov (United States)

    Gomendio, Montserrat; Tourmente, Maximiliano; Roldan, Eduardo R S

    2011-10-22

    The hypothesis that sperm competition should favour increases in sperm size, because it results in faster swimming speeds, has received support from studies on many taxa, but remains contentious for mammals. We suggest that this may be because mammalian lineages respond differently to sexual selection, owing to major differences in body size, which are associated with differences in mass-specific metabolic rate. Recent evidence suggests that cellular metabolic rate also scales with body size, so that small mammals have cells that process energy and resources from the environment at a faster rate. We develop the 'metabolic rate constraint hypothesis' which proposes that low mass-specific metabolic rate among large mammals may limit their ability to respond to sexual selection by increasing sperm size, while this constraint does not exist among small mammals. Here we show that among rodents, which have high mass-specific metabolic rates, sperm size increases under sperm competition, reaching the longest sperm sizes found in eutherian mammals. By contrast, mammalian lineages with large body sizes have small sperm, and while metabolic rate (corrected for body size) influences sperm size, sperm competition levels do not. When all eutherian mammals are analysed jointly, our results suggest that as mass-specific metabolic rate increases, so does maximum sperm size. In addition, species with low mass-specific metabolic rates produce uniformly small sperm, while species with high mass-specific metabolic rates produce a wide range of sperm sizes. These findings support the hypothesis that mass-specific metabolic rates determine the budget available for sperm production: at high levels, sperm size increases in response to sexual selection, while low levels constrain the ability to respond to sexual selection by increasing sperm size. Thus, adaptive and costly traits, such as sperm size, may only evolve under sexual selection when metabolic rate does not constrain cellular

  13. Performance of Africanized honeybee colonies settled by queens selected for different traits

    Directory of Open Access Journals (Sweden)

    Tânia Patrícia Schafaschek

    2016-01-01

    Full Text Available We evaluated varroa infestation and the performance of Africanized honeybee colonies with queens selected for honey and royal jelly production, and also unselected queens, correlating with climatic variables. In Campo Alegre, Santa Catarina State, Brazil, the experiment I used 10 Langstroth hives and in Mafra, Santa Catarina State, Brazil, the experiment II was performed with 15 Schenk hives. A mapping in areas of sealed and unsealed brood, honey and pollen was carried out on days zero, 45 and 90 days after the introduction of the queen. In the experiment I, there was interaction between the type of queen selection and the evaluation period for areas of sealed brood, honey, and total stored food. The group selected for royal jelly production presented larger sealed brood area and smaller honey area at 90 days. Varroa infestation was lower (p < 0.05 at 90 days. The type of queen selection and the evaluation period influenced the sealed brood area, the total brood and the total area occupied in the colony. The high relative humidity caused greater honey storage for the local group. The different groups of queens presented different behavior according to the environment in which they are settled.

  14. Color match of two different ceramic systems to selected shades of one shade guide.

    Science.gov (United States)

    Corciolani, Gabriele; Vichi, Alessandro; Louca, Chris; Ferrari, Marco

    2011-03-01

    There are no consistent indications given by dental manufacturers on how to layer ceramics to achieve a color match to a shade selected from a dental shade guide. The technique for ceramic layering relies primarily on the skill and experience of ceramists and is not easily predictable. The purpose of this study was to evaluate, using a clinical spectrophotometer, the ability to color match shades selected with the 3D-Master shade guide using 2 different ceramic systems. Two ceramic systems were selected for this study, the VITA Omega 900 and VITA VM 13. For both systems, shades 2M3, 3M2, 4M2 of the VITA 3D-Master shade guide were selected. Thirty ceramic discs, 15 mm in diameter, were fabricated with different layer thickness ratios of opaque dentin, dentin, and enamel, maintaining a constant overall thickness. A clinical spectrophotometer (VITA Easyshade) was used for color comparison. The measured ΔE values were statistically analyzed with a 3-way ANOVA and the Tukey HSD test (α=.05). The 3-way ANOVA showed that the ceramic system (P3D-Master shade guide to be within the limits for clinical acceptability (ΔE≤ 3.3). VM 13 showed a statistically better color match. The layering scheme influenced the definitive color of the restoration. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  15. Computer jargon explained

    CERN Document Server

    Enticknap, Nicholas

    2014-01-01

    Computer Jargon Explained is a feature in Computer Weekly publications that discusses 68 of the most commonly used technical computing terms. The book explains what the terms mean and why the terms are important to computer professionals. The text also discusses how the terms relate to the trends and developments that are driving the information technology industry. Computer jargon irritates non-computer people and in turn causes problems for computer people. The technology and the industry are changing so rapidly; it is very hard even for professionals to keep updated. Computer people do not

  16. Gender differences in health-related quality-of-life are partly explained by sociodemographic and socioeconomic variation between adult men and women in the US: evidence from four US nationally representative data sets.

    Science.gov (United States)

    Cherepanov, Dasha; Palta, Mari; Fryback, Dennis G; Robert, Stephanie A

    2010-10-01

    The purpose of this study was to describe gender differences in self-reported health-related quality-of-life (HRQoL) and to examine whether differences are explained by sociodemographic and socioeconomic status (SES) differentials between men and women. Data were from four US nationally representative surveys: US Valuation of the EuroQol EQ-5D Health States Survey (USVEQ), Medical Expenditure Panel Survey (MEPS), National Health Measurement Study (NHMS) and Joint Canada/US Survey of Health (JCUSH). Gender differences were estimated with and without adjustment for sociodemographic and SES indicators using regression within and across data sets with SF-6D, EQ-5D, HUI2, HUI3 and QWB-SA scores as outcomes. Women have lower HRQoL scores than men on all indexes prior to adjustment. Adjusting for age, race, marital status, education and income reduced but did not remove the gender differences, except with HUI3. Adjusting for marital status or income had the largest impact on estimated gender differences. There are clear gender differences in HRQoL in the United States. These differences are partly explained by sociodemographic and SES differentials.

  17. Face-selective regions differ in their ability to classify facial expressions

    Science.gov (United States)

    Zhang, Hui; Japee, Shruti; Nolan, Rachel; Chu, Carlton; Liu, Ning; Ungerleider, Leslie G

    2016-01-01

    Recognition of facial expressions is crucial for effective social interactions. Yet, the extent to which the various face-selective regions in the human brain classify different facial expressions remains unclear. We used functional magnetic resonance imaging (fMRI) and support vector machine pattern classification analysis to determine how well face-selective brain regions are able to decode different categories of facial expression. Subjects participated in a slow event-related fMRI experiment in which they were shown 32 face pictures, portraying four different expressions: neutral, fearful, angry, and happy and belonging to eight different identities. Our results showed that only the amygdala and the posterior superior temporal sulcus (STS) were able to accurately discriminate between these expressions, albeit in different ways: The amygdala discriminated fearful faces from non-fearful faces, whereas STS discriminated neutral from emotional (fearful, angry and happy) faces. In contrast to these findings on the classification of emotional expression, only the fusiform face area (FFA) and anterior inferior temporal cortex (aIT) could discriminate among the various facial identities. Further, the amygdala and STS were better than FFA and aIT at classifying expression, while FFA and aIT were better than the amygdala and STS at classifying identity. Taken together, our findings indicate that the decoding of facial emotion and facial identity occurs in different neural substrates: the amygdala and STS for the former and FFA and aIT for the latter. PMID:26826513

  18. An investigation on the performance characteristics of solar flat plate collector with different selective surface coatings

    OpenAIRE

    Madhukeshwara N., E. S. Prakash

    2012-01-01

    In the present work, investigations are made to study performance characteristics of solar flat plate collector with different selective surface coatings. Flat plate collector is one of the important solar energy trapping device which uses air or water as working fluid. Of the many solar collector concepts presently being developed, the relative simple flat plate solar collector has found the widest application so far. Its characteristics are known, and compared with other collector types, it...

  19. The role of positive selection in determining the molecular cause of species differences in disease

    OpenAIRE

    Foord Steven M; Simmons Mark D; Word Michael; Kumar Vinod; Topp Simon D; Rajagopalan Dilip; Amrine-Madsen Heather; Emes Richard D; Hasan Samiul; Vamathevan Jessica J; Sanseau Philippe; Yang Ziheng; Holbrook Joanna D

    2008-01-01

    Abstract Background Related species, such as humans and chimpanzees, often experience the same disease with varying degrees of pathology, as seen in the cases of Alzheimer's disease, or differing symptomatology as in AIDS. Furthermore, certain diseases such as schizophrenia, epithelial cancers and autoimmune disorders are far more frequent in humans than in other species for reasons not associated with lifestyle. Genes that have undergone positive selection during species evolution are indica...

  20. Explaining the Oxbridge Figures.

    Science.gov (United States)

    Davies, Bronwyn; Harre, Rom

    1989-01-01

    Rejects sociobiological theories on female academic achievement and bases findings on social structure to explain why undergraduate women at Oxford University (England) achieve fewer first places and more second places in class honors. Bases theory on bipolarity of gender as an organizing principle of society. Claims that the double bind of social…

  1. Size- and shape-selective isostructural microporous metal-organic frameworks with different effective aperture sizes.

    Science.gov (United States)

    Liu, Xinfang; Oh, Minhak; Lah, Myoung Soo

    2011-06-06

    Two isostructural metal-organic frameworks (MOFs) having micropores of the same "static aperture size" but different "effective aperture size" have been prepared using 5-(pyridin-3-ylethynyl)isophthalic acid as a ligand having two different types of functional units, an isophthalate (iph) unit and a pyridyl unit, simultaneously in a single ligand. The combination of iph unit and Cu (or Zn) ion led to two-dimensional layers of Kagomé (kgm) net topology, the layers being further pillared by the internal auxiliary pyridyl unit to form a three-dimensional microporous framework having two different types of cage-like pores, cage A and cage B, with different aperture sizes and shapes. (1) The MOFs can distinguish the adsorbates (N(2)/Ar) not based on the widely used kinetic diameters of the adsorbates but based on the minimum diameters of the adsorbates, which are more shape dependent. While cage A with a sufficiently large aperture size compared with the size of the adsorbates does not show any size selectivity, cage B with an approximate size match between the adsorbates and the pore apertures shows shape selectivity for the adsorbates. The smaller but spherically shaped Ar atom is not allowed into the pore with the oval-shaped aperture; however, the larger linear N(2) molecule is allowed into the pore with the oval-shaped aperture. (2) Even though the two isostructural MOFs have the same static aperture size of cage B, they show different size selectivity for the adsorbates based on the effective aperture size, which reflects the different extents of the framework flexibility. © 2011 American Chemical Society

  2. Differences in selective pressure on dhps and dhfr drug resistant mutations in western Kenya.

    Science.gov (United States)

    McCollum, Andrea M; Schneider, Kristan A; Griffing, Sean M; Zhou, Zhiyong; Kariuki, Simon; Ter-Kuile, Feiko; Shi, Ya Ping; Slutsker, Laurence; Lal, Altaf A; Udhayakumar, Venkatachalam; Escalante, Ananias A

    2012-03-22

    each other based on a theoretical model tailored to P. falciparum. The data indicate that drug selection acted differently on the resistant alleles of dhfr and dhps, as evidenced by fitness differences. Thus a combination drug therapy such as SP, by itself, does not appear to select for "multidrug"-resistant parasites in areas with high recombination rate. The complexity of these observations emphasizes the importance of population-based studies to evaluate the effects of strong drug selection on Plasmodium falciparum populations.

  3. [Selective enrichment of Pseudomonas spp. in the rhizoplane of different plant species].

    Science.gov (United States)

    Marrero, Mariana A; Agaras, Betina; Wall, Luis G; Valverde, Claudio

    2015-01-01

    In contrast to rhizobia-legume symbiosis, the specificity for root colonization by pseudomonads seems to be less strict. However, several studies about bacterial diversity in the rhizosphere highlight the influence of plant species on the selective enrichment of certain microorganisms from the bulk soil community. In order to evaluate the effect that different crops have on the structure of pseudomonad community on the root surface, we performed plant trap experiments, using surface-disinfected maize, wheat or soybean seeds that were sown in pots containing the same pristine soil as substrate. Rhizoplane suspensions were plated on a selective medium for Pseudomonas, and pooled colonies served as DNA source to carry out PCR-RFLP community structure analysis of the pseudomonads-specific marker genes oprF and gacA. PCR-RFLP profiles were grouped by plant species, and were distinguished from those of bulk soil samples. Partial sequencing of 16S rDNA genes of some representative colonies of Pseudomonas confirmed the selective enrichment of distinctive genotypes in the rhizoplane of each plant species. These results support the idea that the root systems of agricultural crops such as soybean, maize and wheat, select differential sets of pseudomonads from the native microbial repertoire inhabiting the bulk soil. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Unemployment in Scandinavia during an economic crisis: cross-national differences in health selection.

    Science.gov (United States)

    Heggebø, Kristian

    2015-04-01

    Are people with ill health more prone to unemployment during the ongoing economic crisis? Is this health selection more visible among people with low education, women, or the young? The current paper investigates these questions in the Scandinavian context using the longitudinal part of the EU-SILC data material. Generalized least squares analysis indicates that people with ill health are laid off to a higher degree than their healthy counterparts in Denmark, but not in Norway and Sweden. Additionally, young individuals (higher probability of unemployment in both Norway and Sweden, but not in Denmark. Neither women with ill health, nor individuals with low educational qualifications and ill health, are more likely to lose their jobs in Scandinavia. Individual level (and calendar year) fixed effects analysis confirms the existence of health selection out of employment in Denmark, whereas there is no suggestion of health selection in Sweden and Norway, except among young individuals. This finding could be related to the differing labor market demand the three Scandinavian countries have experienced during and preceding the study period (2007-2010). Another possible explanation for the cross-national differences is connected to the Danish "flexicurity" model, where the employment protection is rather weak. People with ill health, and hence more unstable labor market attachment, could be more vulnerable in such an arrangement. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Different pioneer plant species select specific rhizosphere bacterial communities in a high mountain environment.

    Science.gov (United States)

    Ciccazzo, Sonia; Esposito, Alfonso; Rolli, Eleonora; Zerbe, Stefan; Daffonchio, Daniele; Brusetti, Lorenzo

    2014-01-01

    The rhizobacterial communities of 29 pioneer plants belonging to 12 species were investigated in an alpine ecosystem to assess if plants from different species could select for specific rhizobacterial communities. Rhizospheres and unvegetated soils were collected from a floristic pioneer stage plot at 2,400 m a.s.l. in the forefield of Weisskugel Glacier (Matsch Valley, South Tyrol, Italy), after 160 years of glacier retreat. To allow for a culture-independent perspective, total environmental DNA was extracted from both rhizosphere and bare soil samples and analyzed by Automated Ribosomal Intergenic Spacer Analysis (ARISA) and Denaturing Gradient Gel Electrophoresis (DGGE). ARISA fingerprinting showed that rhizobacterial genetic structure was extremely different from bare soil bacterial communities while rhizobacterial communities clustered strictly together according to the plant species. Sequencing of DGGE bands showed that rhizobacterial communities were mainly composed of Acidobacteria and Proteobacteria whereas bare soil was colonized by Acidobacteria and Clostridia. UniFrac significance calculated on DGGE results confirmed the rhizosphere effect exerted by the 12 species and showed different bacterial communities (P < 0.05) associated with all the plant species. These results pointed out that specific rhizobacterial communities were selected by pioneer plants of different species in a high mountain ecosystem characterized by oligotrophic and harsh environmental conditions, during an early primary succession.

  6. Transduction of selective recognition by preorganized ionophores, K$#+$# selectivity of the different 1,3-diethoxycalix[4]arene crown ether conformers

    NARCIS (Netherlands)

    Brzozka, Zbigniew; Lammerink, Ben; Reinhoudt, David; Ghidini, Eleonora; Ungaro, Rocco

    1993-01-01

    Three different conformers of 1,3-diethoxy-p-tert-butylcalix[4]arene crown ethers have been used to study the effect of the ionophore preorganization on the potentiometric K+-selectivity. Selectivities were measured for chemically modified field effect transistors (CHEMFETs) and membrane

  7. Analysing the differences between theoretical and implemented supply chain strategies in selected organisations

    Directory of Open Access Journals (Sweden)

    Danie J. Nel

    2011-11-01

    Full Text Available Organisations can use supply chain strategies to gain a competitive advantage for the supply chain. A competitive advantage can be achieved by means of low cost or by means of differentiation. However, organisations have to implement the correct supply chain strategy. Returns on investment can be compromised if organisations implement an incorrect supply chain strategy. The objective of the article is to analyse the differences between theoretically implied and implemented supply chain strategies within selected organisations. The differences between supply chain strategies implied by literature and those implemented by selected organisations are analysed by determining how the organisations are managing their supply chain drivers. Organisations with lean supply chains should manage their supply chain drivers to achieve efficiency, while organisations with agile supply chains should manage their supply chain drivers with responsiveness towards customers' needs in mind. Non-probability sampling was used to include 13 organisations in the research. Six organisations are implementing different supply chain strategies to what literature principles are suggesting to them based on specific supply chain characteristics. An analysis is done on how these six organisations are managing their supply chain drivers.

  8. Differences in selectivity to natural images in early visual areas (V1-V3).

    Science.gov (United States)

    Coggan, David D; Allen, Luke A; Farrar, Oliver R H; Gouws, Andre D; Morland, Antony B; Baker, Daniel H; Andrews, Timothy J

    2017-05-26

    High-level regions of the ventral visual pathway respond more to intact objects compared to scrambled objects. The aim of this study was to determine if this selectivity for objects emerges at an earlier stage of processing. Visual areas (V1-V3) were defined for each participant using retinotopic mapping. Participants then viewed intact and scrambled images from different object categories (bottle, chair, face, house, shoe) while neural responses were measured using fMRI. Our rationale for using scrambled images is that they contain the same low-level properties as the intact objects, but lack the higher-order combinations of features that are characteristic of natural images. Neural responses were higher for scrambled than intact images in all regions. However, the difference between intact and scrambled images was smaller in V3 compared to V1 and V2. Next, we measured the spatial patterns of response to intact and scrambled images from different object categories. We found higher within-category compared to between category correlations for both intact and scrambled images demonstrating distinct patterns of response. Spatial patterns of response were more distinct for intact compared to scrambled images in V3, but not in V1 or V2. These findings demonstrate the emergence of selectivity to natural images in V3.

  9. Effect of different oral oxytetracycline treatment regimes on selection of antimicrobial resistant coliforms in nursery pigs.

    Science.gov (United States)

    Herrero-Fresno, Ana; Zachariasen, Camilla; Nørholm, Nanna; Holm, Anders; Christiansen, Lasse Engbo; Olsen, John Elmerdahl

    2017-09-01

    A major concern derived from using antimicrobials in pig production is the development of resistance. This study aimed to assess the impact of selected combinations of oral dose and duration of treatment with oxytetracycline (OTC) on selection of tetracycline resistant (TET-R) coliforms recovered from swine feces. The work encompassed two studies: 1) OTC 5mg/kg and 20mg/kg were administered to nursery pigs for 3 and 10days, respectively, under controlled experimental conditions, and 2) 10mg/kg, 20mg/kg and 30mg/kg OTC were given to a higher number of pigs for 6, 3 and 2days, respectively, under field conditions. Statistical modeling was applied to analyze trends in the proportion of TET-R coliforms. In the experimental study, no statistical difference in proportion of TET-R coliforms was observed between treatments at the end of the trial (day 18) and compared to day 0. In the field study, treatment had a significant effect on the proportion of TET-R bacteria two days after the end of treatment (2dAT) with the regimes "low dose-six days" and "medium dose-three days" yielding the highest and lowest proportions of TET-R strains, respectively. No indication of co-selection for ampicillin- and sulphonamide -R bacteria was observed for any treatment at 2dAT. By the end of the nursery period, the proportion of TET-R bacteria was not significantly different between treatments and compared to day 0. Our results suggest that similar resistance levels might be obtained by using different treatment regimes regardless of the combinations of oral dose-duration of treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Different Levels of DNA Methylation Detected in Human Sperms after Morphological Selection Using High Magnification Microscopy

    Directory of Open Access Journals (Sweden)

    Nino Guy Cassuto

    2016-01-01

    Full Text Available Objective. To analyze DNA methylation levels between two groups of spermatozoa taken from the same sample, following morphological selection by high magnification (HM at 6100x microscopy. A prospective study was conducted and studied 876 spermatozoa from 10 randomly selected men. Sperm morphology was characterized at HM according to criteria previously established. High-scoring Score 6 and low-scoring Score 0 sperm were selected. Sperm DNA methylation level was assessed using an immunoassay method targeting 5-methylcytosine residues by fluorescence microscopy with imaging analysis system to detect DNA methylation in single spermatozoon. Results. In total, 448 S6 spermatozoa and 428 S0 spermatozoa were analyzed. A strong relationship was found between sperm DNA methylation levels and sperm morphology observed at HM. Sperm DNA methylation level in the S6 group was significantly lower compared with that in the S0 group (p<10-6, OR = 2.4; and p<0.001, as determined using the Wilcoxon test. Conclusion. Differences in DNA methylation levels are associated with sperm morphology variations as observed at HM, which allows spermatozoa with abnormal levels to be discarded and ultimately decrease birth defects, malformations, and epigenetic diseases that may be transmitted from sperm to offspring in ICSI.

  11. Ion imprinted polymeric nanoparticles for selective separation and sensitive determination of zinc ions in different matrices.

    Science.gov (United States)

    Shamsipur, Mojtaba; Rajabi, Hamid Reza; Pourmortazavi, Seied Mahdi; Roushani, Mahmoud

    2014-01-03

    Preparation of Zn(2+) ion-imprinted polymer (Zn-IIP) nanoparticles is presented in this report. The Zn-IIP nanoparticles are prepared by dissolving stoichiometric amounts of zinc nitrate and selected chelating ligand, 3,5,7,20,40-pentahydroxyflavone, in 15 mL ethanol-acetonitrile (2:1; v/v) mixture as a porogen solvent in the presence of ethylene glycol-dimethacrylate (EGDMA) as cross-linking, methacrylic acid (MAA) as functional monomer, and 2,2-azobisisobutyronitrile (AIBN) as initiator. After polymerization, Cavities in the polymer particles corresponding to the Zn(2+) ions were created by leaching the polymer in HCl aqueous solution. The synthesized IIPs were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, fluorescence spectroscopy and thermal analysis techniques. Also, the pH range for rebinding of Zn(2+) ion on the IIP and equilibrium binding time were optimized, using flame atomic absorption spectrometry. In selectivity study, it was found that imprinting results increased affinity of the material toward Zn(2+) ion over other competitor metal ions with the same charge and close ionic radius. The prepared IIPs were repeatedly used and regenerated for six times without any significant decrease in polymer binding affinities. Finally, the prepared sorbent was successfully applied to the selective recognition and determination of zinc ion in different real samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Professional care seeking for mental health problems among women and men in Europe: the role of socioeconomic, family-related and mental health status factors in explaining gender differences.

    Science.gov (United States)

    Buffel, V; Van de Velde, S; Bracke, P

    2014-10-01

    This comparative study examines cross-national variation in gender differences in primary and specialized mental health care use in Europe. We investigate to what extent socioeconomic, family-related, and mental health factors explain the gender difference, and how the impact of these groups of determinants on gender differences in mental health care use varies between countries. Data from the Eurobarometer 248 (2005-2006) for 29 European countries is used and country-specific logistic regression analyses are performed. Gender differences in professional care seeking are largely need based. In almost one-third of the countries examined, the gender difference is mainly attributable to women's poorer mental health status. However, in some countries, family and socioeconomic characteristics also have an independent contribution to the gender difference in mental health care use. Women's higher likelihood of a lower socioeconomic position, might partly explain their higher primary care use, while in some countries, it restricts their specialized care use. In addition, some social conditions, as having children and being widowed, seem to function in a few countries as suppressors of women's care use. Our study has shown that the gender difference in mental health care use, with women having a higher care use, is not a consistent European phenomenon and is dependent on the type of care provider, with greater gender inequity in the use of primary health care. The social roles adopted by men and women have in some countries on top of the mental health status a relevant influence on the greater tendency among women to contact a care provider. How the socioeconomic and family characteristics moderate the relation between gender and mental health care use is not straightforward and country dependent.

  13. Signatures of recent directional selection under different models of population expansion during colonization of new selective environments.

    Science.gov (United States)

    Kim, Yuseob; Gulisija, Davorka

    2010-02-01

    A major problem in population genetics is understanding how the genomic pattern of polymorphism is shaped by natural selection and the demographic history of populations. Complex population dynamics confounds patterns of variation and poses serious challenges for identifying genomic imprints of selection. We examine patterns of polymorphism using computer simulations and provide analytical predictions for hitchhiking effects under two models of adaptive niche expansion. The population split (PS) model assumes the separation of a founding population followed by directional selection in the new environment. Here, the new population undergoes a bottleneck and later expands in size. This model has been used in previous studies to account for demographic effects when testing for signatures of selection under colonization or domestication. The genotype-dependent colonization and introgression (GDCI) model is proposed in this study and assumes that a small number of migrants carrying adaptive genotype found a new population, which then grows logistically. The GDCI model also allows for constant migration between the parental and the new population. Both models predict reduction in variation and excess of high frequency of derived alleles relative to neutral expectations, with and without hitchhiking. Under comparable conditions, the GDCI model results in greater reduction in expected heterozygosity and more skew of the site frequency spectrum than the PS model. We also find that soft selective sweeps (fixation of multiple copies of a beneficial mutation) occurs less often in the GDCI model than in the PS model. This result demonstrates the importance of correctly modeling the ecological process in inferring adaptive evolution using DNA sequence polymorphism.

  14. Linear Algebra Thoroughly Explained

    CERN Document Server

    Vujičić, Milan

    2008-01-01

    Linear Algebra Thoroughly Explained provides a comprehensive introduction to the subject suitable for adoption as a self-contained text for courses at undergraduate and postgraduate level. The clear and comprehensive presentation of the basic theory is illustrated throughout with an abundance of worked examples. The book is written for teachers and students of linear algebra at all levels and across mathematics and the applied sciences, particularly physics and engineering. It will also be an invaluable addition to research libraries as a comprehensive resource book for the subject.

  15. Blocking performance of a burst-outputted model considering different service rates and different output port-selected probabilities in an optical burst switching core node

    Science.gov (United States)

    Hou, Rui; Changyue, Jiana; He, Tingting; Mao, Tengyue; Yu, Jianwei; Lei, Bo

    2013-04-01

    In an optical burst switching core node, each output port is equipped with a different network interface unit that can provide a specific data rate. Bursts will use different probabilities of select output ports, which is in accordance to the path-length metric-based routing optimal algorithm and wavelength resource situation. Previous studies ignore this issue. We establish a burst-outputted model considering the different service rate of output ports and different port-selected probabilities. We calculate burst-blocking probability and analyze the relationship between service rate and output-port-selected probability in detail.

  16. Why Do Floral Perfumes Become Different? Region-Specific Selection on Floral Scent in a Terrestrial Orchid.

    Science.gov (United States)

    Gross, Karin; Sun, Mimi; Schiestl, Florian P

    2016-01-01

    Geographically structured phenotypic selection can lead to adaptive divergence. However, in flowering plants, such divergent selection has rarely been shown, and selection on floral signals is generally little understood. In this study, we measured phenotypic selection on display size, floral color, and floral scent in four lowland and four mountain populations of the nectar-rewarding terrestrial orchid Gymnadenia odoratissima in two years. We also quantified population differences in these traits and pollinator community composition. Our results show positive selection on display size and positive, negative, or absence of selection on different scent compounds and floral color. Selection on the main scent compounds was consistently stronger in the lowlands than in the mountains, and lowland plants emitted higher amounts of most of these compounds. Pollinator community composition also differed between regions, suggesting different pollinators select for differences in floral volatiles. Overall, our study is the first to document consistent regional differences in selection on floral scent, suggesting this pattern of selection is one of the evolutionary forces contributing to regional divergence in floral chemical signaling.

  17. Explaining embodied cognition results.

    Science.gov (United States)

    Lakoff, George

    2012-10-01

    From the late 1950s until 1975, cognition was understood mainly as disembodied symbol manipulation in cognitive psychology, linguistics, artificial intelligence, and the nascent field of Cognitive Science. The idea of embodied cognition entered the field of Cognitive Linguistics at its beginning in 1975. Since then, cognitive linguists, working with neuroscientists, computer scientists, and experimental psychologists, have been developing a neural theory of thought and language (NTTL). Central to NTTL are the following ideas: (a) we think with our brains, that is, thought is physical and is carried out by functional neural circuitry; (b) what makes thought meaningful are the ways those neural circuits are connected to the body and characterize embodied experience; (c) so-called abstract ideas are embodied in this way as well, as is language. Experimental results in embodied cognition are seen not only as confirming NTTL but also explained via NTTL, mostly via the neural theory of conceptual metaphor. Left behind more than three decades ago is the old idea that cognition uses the abstract manipulation of disembodied symbols that are meaningless in themselves but that somehow constitute internal "representations of external reality" without serious mediation by the body and brain. This article uniquely explains the connections between embodied cognition results since that time and results from cognitive linguistics, experimental psychology, computational modeling, and neuroscience. Copyright © 2012 Cognitive Science Society, Inc.

  18. Comparison between different selection criteria in the genetic evaluation of Valle del Belice sheep

    Directory of Open Access Journals (Sweden)

    F. Firpo

    2011-03-01

    Full Text Available Lactation length in dairy sheep affects milk yield like other genetic and environmental factors. The length of the production period is affected by management decisions such as culling, mating and particularly ranking of animals with different parity and lambing in different months or seasons. Moreover the low heritability of lactation length (Barillet and Boichard, 1987; Dahlin et al., 1998 does not allow its use as a selection criterion. For this reason to achieve a good reliability in phenotypic and genetic evaluation of dairy species, production variability caused by systematic environmental effects must be removed. This is of particular interest for dairy sheep and goats reared in Sicily, where the typical production system is based on pasture, and related food availability is strongly affected by seasonal and annual climatic variations, which results in considerable variations in daily yields........

  19. Sociodemographic differences in selected eating practices among alternative high school students.

    Science.gov (United States)

    Arcan, Chrisa; Kubik, Martha Y; Fulkerson, Jayne A; Story, Mary

    2009-05-01

    Students attending alternative high schools are an at-risk group of youth for poor health behaviors and obesity. However, little is known about their dietary practices. To examine associations between sex, race/ethnicity, and socioeconomic status and selected dietary practices, including consumption of sugar-sweetened beverages, high-fat foods, and fruits and vegetables and fast-food restaurant use, among students attending alternative high schools. Population-based, cross-sectional study. A convenience sample of adolescents (n=145; 52% men; 63% aged sociodemographic differences in fruit/vegetable consumption. Higher socioeconomic status was associated with a higher consumption of regular soda (P=0.027). Racial/ethnic and sex differences in the consumption of regular soda, high-fat foods, and fast-food restaurant use among alternative high school students underscores the importance of implementing health promotion programs in alternative high schools.

  20. Fitness components and natural selection: why are there different patterns on the emergence of drug resistance in Plasmodium falciparum and Plasmodium vivax?

    Directory of Open Access Journals (Sweden)

    Schneider Kristan A

    2013-01-01

    Full Text Available Abstract Background Considering the distinct biological characteristics of Plasmodium species is crucial for control and elimination efforts, in particular when facing the spread of drug resistance. Whereas the evolutionary fitness of all malarial species could be approximated by the probability of being taken by a mosquito and then infecting a new host, the actual steps in the malaria life cycle leading to a successful transmission event show differences among Plasmodium species. These “steps” are called fitness components. Differences in terms of fitness components may affect how selection imposed by interventions, e.g. drug treatments, differentially acts on each Plasmodium species. Thus, a successful malaria control or elimination programme should understand how differences in fitness components among different malaria species could affect adaptive evolution (e.g. the emergence of drug resistance. In this investigation, the interactions between some fitness components and natural selection are explored. Methods A population-genetic model is formulated that qualitatively explains how different fitness components (in particular gametocytogenesis and longevity of gametocytes affect selection acting on merozoites during the erythrocytic cycle. By comparing Plasmodium falciparum and Plasmodium vivax, the interplay of parasitaemia and gametocytaemia dynamics in determining fitness is modelled under circumstances that allow contrasting solely the differences between these two parasites in terms of their fitness components. Results By simulating fitness components, it is shown that selection acting on merozoites (e.g., on drug resistant mutations or malaria antigens is more efficient in P. falciparum than in P. vivax. These results could explain, at least in part, why resistance against drugs, such as chloroquine (CQ is highly prevalent in P. falciparum worldwide, while CQ is still a successful treatment for P. vivax despite its massive use

  1. Explaining mirror-touch synesthesia.

    Science.gov (United States)

    Ward, Jamie; Banissy, Michael J

    2015-01-01

    Mirror-touch synesthesia (MTS) is the conscious experience of tactile sensations induced by seeing someone else touched. This paper considers two different, although not mutually exclusive, theoretical explanations and, in the final section, considers the relation between MTS and other forms of synesthesia and also other kinds of vicarious perception (e.g., contagious yawning). The Threshold Theory explains MTS in terms of hyper-activity within a mirror system for touch and/or pain. This offers a good account for some of the evidence (e.g., from fMRI) but fails to explain the whole pattern (e.g., structural brain differences outside of this system; performance on some tests of social cognition). The Self-Other Theory explains MTS in terms of disturbances in the ability to distinguish the self from others. This can be construed in terms of over-extension of the bodily self in to others, or as difficulties in the control of body-based self-other representations. In this account, MTS is a symptom of a broader cognitive profile. We suggest this meets the criteria for synesthesia, despite the proximal causal mechanisms remaining largely unknown, and that the tendency to localize vicarious sensory experiences distinguishes it from other kinds of seemingly related phenomena (e.g., non-localized affective responses to observing pain).

  2. Selective actions of Lynx proteins on different nicotinic acetylcholine receptors in the locust, Locusta migratoria manilensis.

    Science.gov (United States)

    Wang, Xin; Bao, Haibo; Sun, Huahua; Zhang, Yixi; Fang, Jichao; Liu, Qinghong; Liu, Zewen

    2015-08-01

    Nicotinic acetylcholine receptors (nAChRs) are major neurotransmitter receptors and targets of neonicotinoid insecticides in the insect nervous system. The full function of nAChRs is often dependent on associated proteins, such as chaperones, regulators and modulators. Here, three Lynx (Ly-6/neurotoxin) proteins, Loc-lynx1, Loc-lynx2 and Loc-lynx3, were identified in the locust, Locusta migratoria manilensis. Co-expression with Lynx resulted in a dramatic increase in agonist-evoked macroscopic currents on nAChRs Locα1/β2 and Locα2/β2 in Xenopus oocytes, but no changes in agonist sensitivity. Loc-lynx1 and Loc-lynx3 only modulated nAChRs Locα1/β2 while Loc-lynx2 modulated Locα2/β2 specifically. Meanwhile, Loc-lynx1 induced a more significant increase in currents evoked by imidacloprid and epibatidine than Loc-lynx3, and the effects of Loc-lynx1 on imidacloprid and epibatidine were significantly higher than those on acetylcholine. Among three lynx proteins, only Loc-lynx1 significantly increased [(3) H]epibatidine binding on Locα1/β2. The results indicated that Loc-lynx1 had different modulation patterns in nAChRs compared to Loc-lynx2 and Loc-lynx3. Taken together, these findings indicated that three Lynx proteins were nAChR modulators and had selective activities in different nAChRs. Lynx proteins might display their selectivities from three aspects: nAChR subtypes, various agonists and different modulation patterns. Insect Lynx (Ly-6/neurotoxin) proteins act as the allosteric modulators on insect nicotinic acetylcholine receptors (nAChRs), the important targets of insecticides. We found that insect lynx proteins showed their selectivities from at least three aspects: nAChR subtypes, various agonists and different modulation patterns. © 2015 International Society for Neurochemistry.

  3. The human cerebral cortex is neither one nor many: neuronal distribution reveals two quantitatively different zones in the gray matter, three in the white matter, and explains local variations in cortical folding

    Science.gov (United States)

    Ribeiro, Pedro F. M.; Ventura-Antunes, Lissa; Gabi, Mariana; Mota, Bruno; Grinberg, Lea T.; Farfel, José M.; Ferretti-Rebustini, Renata E. L.; Leite, Renata E. P.; Filho, Wilson J.; Herculano-Houzel, Suzana

    2013-01-01

    The human prefrontal cortex has been considered different in several aspects and relatively enlarged compared to the rest of the cortical areas. Here we determine whether the white and gray matter of the prefrontal portion of the human cerebral cortex have similar or different cellular compositions relative to the rest of the cortical regions by applying the Isotropic Fractionator to analyze the distribution of neurons along the entire anteroposterior axis of the cortex, and its relationship with the degree of gyrification, number of neurons under the cortical surface, and other parameters. The prefrontal region shares with the remainder of the cerebral cortex (except for occipital cortex) the same relationship between cortical volume and number of neurons. In contrast, both occipital and prefrontal areas vary from other cortical areas in their connectivity through the white matter, with a systematic reduction of cortical connectivity through the white matter and an increase of the mean axon caliber along the anteroposterior axis. These two parameters explain local differences in the distribution of neurons underneath the cortical surface. We also show that local variations in cortical folding are neither a function of local numbers of neurons nor of cortical thickness, but correlate with properties of the white matter, and are best explained by the folding of the white matter surface. Our results suggest that the human cerebral cortex is divided in two zones (occipital and non-occipital) that differ in how neurons are distributed across their gray matter volume and in three zones (prefrontal, occipital, and non-occipital) that differ in how neurons are connected through the white matter. Thus, the human prefrontal cortex has the largest fraction of neuronal connectivity through the white matter and the smallest average axonal caliber in the white matter within the cortex, although its neuronal composition fits the pattern found for other, non-occipital areas. PMID

  4. The human cerebral cortex is neither one nor many: Neuronal distribution reveals two quantitatively different zones in the grey matter, three in the white matter, and explains local variations in cortical folding

    Directory of Open Access Journals (Sweden)

    Pedro F. M. Ribeiro

    2013-09-01

    Full Text Available The human prefrontal cortex has been considered different in several aspects and relatively enlarged compared to the rest of the cortical areas. Here we determine whether the white and gray matter of the prefrontal portion of the human cerebral cortex have similar or different cellular compositions relative to the rest of the cortical regions by applying the Isotropic Fractionator to analyze the distribution of neurons along the entire anteroposterior axis of the cortex, and its relationship with the degree of gyrification, number of neurons under the cortical surface, and other parameters. The prefrontal region shares with the remainder of the cerebral cortex (except for occipital cortex the same relationship between cortical volume and number of neurons. In contrast, both occipital and prefrontal areas vary from other cortical areas in their connectivity through the white matter, with a systematic reduction of cortical connectivity through the white matter and an increase of the mean axon caliber along the anteroposterior axis. These two parameters explain local differences in the distribution of neurons underneath the cortical surface. We also show that local variations in cortical folding are neither a function of local numbers of neurons nor of cortical thickness, but correlate with properties of the white matter, and are best explained by the folding of the white matter surface. Our results suggest that the human cerebral cortex is divided in two zones (occipital and non-occipital that differ in how neurons distributed across their grey matter volume and in three zones (prefrontal, occipital, and non-occipital that differ in how neurons are connected through the white matter. Thus, the human prefrontal cortex has the largest fraction of neuronal connectivity through the white matter and the smallest average axonal caliber in the white matter within the cortex, although its neuronal composition fits the pattern found for other, non

  5. Paths to selection on life history loci in different natural environments across the native range of Arabidopsis thaliana

    NARCIS (Netherlands)

    Fournier-Level, A.; Wilczek, A.M.; Cooper, M.D.; Roe, J.L.; Anderson, J.; Eaton, D.; Moyers, B.T.; Petipas, R.H.; Schaeffer, R.N.; Pieper, B.; Reymond, M.; Koornneef, M.; Welch, S.M.; Remington, D.L.; Schmitt, J.

    2013-01-01

    Selection on quantitative trait loci (QTL) may vary among natural environments due to differences in the genetic architecture of traits, environment-specific allelic effects or changes in the direction and magnitude of selection on specific traits. To dissect the environmental differences in

  6. Explaining wartime rape.

    Science.gov (United States)

    Gottschall, Jonathan

    2004-05-01

    In the years since the first reports of mass rapes in the Yugoslavian wars of secession and the genocidal massacres in Rwanda, feminist activists and scholars, human rights organizations, journalists, and social scientists have dedicated unprecedented efforts to document, explain, and seek solutions for the phenomenon of wartime rape. While contributors to this literature agree on much, there is no consensus on causal factors. This paper provides a brief overview of the literature on wartime rape in historical and ethnographical societies and a critical analysis of the four leading explanations for its root causes: the feminist theory, the cultural pathology theory, the strategic rape theory, and the biosocial theory. The paper concludes that the biosocial theory is the only one capable of bringing all the phenomena associated with wartime rape into a single explanatory context.

  7. Does Viewing Explain Doing?

    DEFF Research Database (Denmark)

    Hald, Gert Martin; Kuyper, Lisette; Adam, Philippe C G

    2013-01-01

    that, when controlling for important other factors, SEM consumption influences sexual behaviors. The small to moderate associations that emerged between SEM consumption and sexual behavior after controlling for other variables suggest that SEM is just one factor among many that may influence youth...... hierarchical multiple regression analyses to control for other factors, the association between SEM consumption and a variety of sexual behaviors was found to be significant, accounting for between 0.3% and 4% of the total explained variance in investigated sexual behaviors. CONCLUSIONS: This study suggests......INTRODUCTION: Concerns have been voiced that the use of sexually explicit materials (SEMs) may adversely affect sexual behaviors, particularly in young people. Previous studies have generally found significant associations between SEM consumption and the sexual behaviors investigated. However, most...

  8. Accuracy of Genomewide Selection for Different Traits with Constant Population Size, Heritability, and Number of Markers

    Directory of Open Access Journals (Sweden)

    Emily Combs

    2013-03-01

    Full Text Available In genomewide selection, the expected correlation between predicted performance and true genotypic value is a function of the training population size (, heritability on an entry-mean basis (, and effective number of chromosome segments underlying the trait (. Our objectives were to (i determine how the prediction accuracy of different traits responds to changes in , , and number of markers ( and (ii determine if prediction accuracy is equal across traits if , , and are kept constant. In a simulated population and four empirical populations in maize ( L., barley ( L., and wheat ( L., we added random nongenetic effects to the phenotypic data to reduce to 0.50, 0.30 and 0.20. As expected, increasing , , and increased prediction accuracy. For the same trait within the same population, prediction accuracy was constant for different combinations of and that led to the same . Different traits, however, varied in their prediction accuracy even when , , and were constant. Yield traits had lower prediction accuracy than other traits despite the constant , , and . Empirical evidence and experience on the predictability of different traits are needed in designing training populations.

  9. Comparison of grouper infection with two different iridoviruses using transcriptome sequencing and multiple reference species selection.

    Science.gov (United States)

    Liu, Chun-Cheng; Ho, Li-Ping; Yang, Cin-Hang; Kao, Tsung-Yu; Chou, Hsin-Yiu; Pai, Tun-Wen

    2017-12-01

    Due to high-density aquafarming in Taiwan, groupers are commonly infected with two different iridoviruses: Megalocytivirus (grouper iridovirus of Taiwan, TGIV) and Ranavirus (grouper iridovirus, GIV). Iridoviral diseases cause mass mortality, and surviving fish retain these pathogens, which can then be horizontally transferred. These viruses have therefore become a major challenge for grouper aquaculture. In this study, comparisons of the biological responses of groupers to infection with these two different iridoviruses were performed. A novel approach for transcriptomic analysis was proposed to enhance the discovery of differentially expressed genes and associated biological pathways. In this method, suitable and available reference species are selected from the NCBI taxonomy tree and the Ensembl and KEGG databases instead of either choosing only one model species or adopting the NCBI non-redundant dataset as references. Our results show that selection of multiple appropriate model species as references increases the efficiency and performance of analyses compared to those of traditional approaches. Using this method, 17 shared pathways and 5 specific pathways were found to be significantly differentially expressed following infection with the two iridoviruses, among which 11 pathways were additionally identified based on the proposed method of multiple reference species selection. Among the pathways responsive to infection with a specific iridovirus, the spliceosomal pathway (ko03040; p-value = 0.0011) was exclusively associated with TGIV infection, while the glycolysis/gluconeogenesis pathway (ko00010; p-value = 0.0032) was associated with GIV infection. These findings and designed corresponding biological experiments may facilitate a deeper understanding of the mechanisms by which both TGIV and GIV cause fatal infections, as well as the ways in which they induce different pathologies and symptoms. We believe that the proposed novel mechanism for de novo

  10. Spot the difference : Impact of different selection criteria on observed properties of passive galaxies in zCOSMOS-20k sample

    NARCIS (Netherlands)

    Moresco, M.; Pozzetti, L.; Cimatti, A.; Zamorani, G.; Bolzonella, M.; Lamareille, F.; Mignoli, M.; Zucca, E.; Lilly, S. J.; Carollo, C. M.; Contini, T.; Kneib, J. -P; Le Fèvre, O.; Mainieri, V.; Renzini, A.; Scodeggio, M.; Bardelli, S.; Bongiorno, A.; Caputi, K.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Iovino, A.; Kampczyk, P.; Knobel, C.; Kovač, K.; Le Borgne, J. -F; Le Brun, V.; Maier, C.; Pelló, R.; Peng, Y.; Perez-Montero, E.; Presotto, V.; Silverman, J. D.; Tanaka, M.; Tasca, L.; Tresse, L.; Vergani, D.; Barnes, L.; Bordoloi, R.; Cappi, A.; Diener, C.; Koekemoer, A. M.; Le Floc'h, E.; López-Sanjuan, C.; McCracken, H. J.; Nair, P.; Oesch, P.; Scarlata, C.; Scoville, N.; Welikala, N.

    2013-01-01

    Aims. We present the analysis of photometric, spectroscopic, and morphological properties for differently selected samples of passive galaxies up to z = 1 extracted from the zCOSMOS-20k spectroscopic survey. This analysis intends to explore the dependence of galaxy properties on the selection

  11. Selectively detail-enhanced fusion of differently exposed images with moving objects.

    Science.gov (United States)

    Li, Zhengguo; Zheng, Jinghong; Zhu, Zijian; Wu, Shiqian

    2014-10-01

    In this paper, we introduce an exposure fusion scheme for differently exposed images with moving objects. The proposed scheme comprises a ghost removal algorithm in a low dynamic range domain and a selectively detail-enhanced exposure fusion algorithm. The proposed ghost removal algorithm includes a bidirectional normalization-based method for the detection of nonconsistent pixels and a two-round hybrid method for the correction of nonconsistent pixels. Our detail-enhanced exposure fusion algorithm includes a content adaptive bilateral filter, which extracts fine details from all the corrected images simultaneously in gradient domain. The final image is synthesized by selectively adding the extracted fine details to an intermediate image that is generated by fusing all the corrected images via an existing multiscale algorithm. The proposed exposure fusion algorithm allows fine details to be exaggerated while existing exposure fusion algorithms do not provide such an option. The proposed scheme usually outperforms existing exposure fusion schemes when there are moving objects in real scenes. In addition, the proposed ghost removal algorithm is simpler than existing ghost removal algorithms and is suitable for mobile devices with limited computational resource.

  12. Selectivity differences of water-soluble vitamins separated on hydrophilic interaction stationary phases.

    Science.gov (United States)

    Yang, Yuanzhong; Boysen, Reinhard I; Hearn, Milton T W

    2013-06-01

    In this study, the retention behavior and selectivity differences of water-soluble vitamins were evaluated with three types of polar stationary phases (i.e. an underivatized silica phase, an amide phase, and an amino phase) operated in the hydrophilic interaction chromatographic mode with ESI mass spectrometric detection. The effects of mobile phase composition, including buffer pH and concentration, on the retention and selectivity of the vitamins were investigated. In all stationary phases, the neutral or weakly charged vitamins exhibited very weak retention under each of the pH conditions, while the acidic and more basic vitamins showed diverse retention behaviors. With the underivatized silica phase, increasing the salt concentration of the mobile phase resulted in enhanced retention of the acidic vitamins, but decreased retention of the basic vitamins. These observations thus signify the involvement of secondary mechanisms, such as electrostatic interaction in the retention of these analytes. Under optimized conditions, a baseline separation of all vitamins was achieved with excellent peak efficiency. In addition, the effects of water content in the sample on retention and peak efficiency were examined, with sample stacking effects observed when the injected sample contained a high amount of water. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Phenotypic and molecular differences between rats selectively bred to voluntarily run high vs. low nightly distances.

    Science.gov (United States)

    Roberts, Michael D; Brown, Jacob D; Company, Joseph M; Oberle, Lauren P; Heese, Alexander J; Toedebusch, Ryan G; Wells, Kevin D; Cruthirds, Clayton L; Knouse, John A; Ferreira, J Andries; Childs, Thomas E; Brown, Marybeth; Booth, Frank W

    2013-06-01

    The purpose of the present study was to partially phenotype male and female rats from generations 8-10 (G8-G10) that had been selectively bred to possess low (LVR) vs. high voluntary running (HVR) behavior. Over the first 6 days with wheels, 34-day-old G8 male and female LVRs ran shorter distances (P values, while LVR did not lose or gain fat mass during the 6-day voluntary running period. RNA deep sequencing efforts in the nucleus accumbens showed only eight transcripts to be >1.5-fold differentially expressed between lines in HVR and LVR nonrunners. Interestingly, HVRs presented less Oprd1 mRNA, which ties in to potential differences in dopaminergic signaling between lines. This unique animal model provides further evidence as to how exercise may be mechanistically regulated.

  14. Warm and homely or cold and beautiful? Sex differences in trading off traits in mate selection.

    Science.gov (United States)

    Fletcher, Garth J O; Tither, Jacqueline M; O'Loughlin, Claire; Friesen, Myron; Overall, Nickola

    2004-06-01

    Prior research and theory suggest that people use three main sets of criteria in mate selection: warmth/trustworthiness, attractiveness/vitality, and status/resources. In two studies, men and women made mating choices between pairs of hypothetical potential partners and were forced to make trade-offs among these three criteria (e.g., warm and homely vs. cold and attractive). As predicted, women (relative to men) placed greater importance on warmth/trustworthiness and status/resources in a potential mate but less importance on attractiveness/vitality. In addition, as expected (a) ratings of ideal standards partly mediated the link between sex and mate choices, (b) ideal standards declined in importance from long-term to short-term relationships, with the exception of attractiveness/vitality, and unexpectedly, (c) sex differences were higher for long-term (compared to short-term) mate choice. Explanations and implications are discussed.

  15. Best Fit and Selection of Theoretical Flood Frequency Distributions Based on Different Runoff Generation Mechanisms

    Directory of Open Access Journals (Sweden)

    Vito Iacobellis

    2010-05-01

    Full Text Available Theoretically derived distributions allow the detection of dominant runoff generation mechanisms as key signatures of hydrologic similarity. We used two theoretically derived distributions of flood peak annual maxima: the first is the “IF” distribution, which exploits the variable source area concept, coupled with a runoff threshold having scaling properties; the second is the Two Component-IF (TCIF distribution, which generalizes the IF distribution, and is based on two different threshold mechanisms, associated with ordinary and extraordinary events, respectively. By focusing on the application of both models to two river basins, of sub-humid and semi-arid climate in Southern Italy, we present an ad hoc procedure for the estimation of parameters and we discuss the use of appropriate techniques for model selection, in the case of nested distributions.

  16. Mate Selection Criteria: A Trait Desirability Assessment Study of Sex Differences in Serbia

    Directory of Open Access Journals (Sweden)

    Bojan Todosijević

    2003-01-01

    Full Text Available This paper examines predictions from evolutionary and socio-structural perspectives on sex differences in mate selection criteria on a sample of 127 respondents from Serbia. The respondents, mainly college students, were asked to assess the degree of un/desirability of sixty behavioural and personality traits in a potential mate, on the 7-point Likert type scale. The sexes strongly agree in general ranking of the traits' desirability. The obtained statistically significant differences tend to favour the evolutionary interpretation. The largest differences are in the perceived desirability of thinness, strength, fearfulness, self-pity, fragility, aggressiveness, and beauty. Males perceived all these traits as more desirable (or less undesirable than females, except that females valued strength more positively. Male respondents are less troubled by negative character traits of a potential partner, while females are less concerned with a partner's physical appearance. The higher status of women correlated positively with their concern with a mate's potential socio-economic status, contrary to the prediction of the socio-structural model.

  17. Comparison of different automatic adaptive threshold selection techniques for estimating discharge from river width

    Science.gov (United States)

    Elmi, Omid; Javad Tourian, Mohammad; Sneeuw, Nico

    2015-04-01

    The importance of river discharge monitoring is critical for e.g., water resource planning, climate change, hazard monitoring. River discharge has been measured at in situ gauges for more than a century. Despite various attempts, some basins are still ungauged. Moreover, a reduction in the number of worldwide gauging stations increases the interest to employ remote sensing data for river discharge monitoring. Finding an empirical relationship between simultaneous in situ measurements of discharge and river widths derived from satellite imagery has been introduced as a straightforward remote sensing alternative. Classifying water and land in an image is the primary task for defining the river width. Water appears dark in the near infrared and infrared bands in satellite images. As a result low values in the histogram usually represent the water content. In this way, applying a threshold on the image histogram and separating into two different classes is one of the most efficient techniques to build a water mask. Beside its simple definition, finding the appropriate threshold value in each image is the most critical issue. The threshold is variable due to changes in the water level, river extent, atmosphere, sunlight radiation, onboard calibration of the satellite over time. These complexities in water body classification are the main source of error in river width estimation. In this study, we are looking for the most efficient adaptive threshold algorithm to estimate the river discharge. To do this, all cloud free MODIS images coincident with the in situ measurement are collected. Next a number of automatic threshold selection techniques are employed to generate different dynamic water masks. Then, for each of them a separate empirical relationship between river widths and discharge measurements are determined. Through these empirical relationships, we estimate river discharge at the gauge and then validate our results against in situ measurements and also

  18. Individual Differences in Temporal Selective Attention as Reflected in Pupil Dilation.

    Directory of Open Access Journals (Sweden)

    Charlotte Willems

    Full Text Available Attention is restricted for the second of two targets when it is presented within 200-500 ms of the first target. This attentional blink (AB phenomenon allows one to study the dynamics of temporal selective attention by varying the interval between the two targets (T1 and T2. Whereas the AB has long been considered as a robust and universal cognitive limitation, several studies have demonstrated that AB task performance greatly differs between individuals, with some individuals showing no AB whatsoever.Here, we studied these individual differences in AB task performance in relation to differences in attentional timing. Furthermore, we investigated whether AB magnitude is predictive for the amount of attention allocated to T1. For both these purposes pupil dilation was measured, and analyzed with our recently developed deconvolution method. We found that the dynamics of temporal attention in small versus large blinkers differ in a number of ways. Individuals with a relatively small AB magnitude seem better able to preserve temporal order information. In addition, they are quicker to allocate attention to both T1 and T2 than large blinkers. Although a popular explanation of the AB is that it is caused by an unnecessary overinvestment of attention allocated to T1, a more complex picture emerged from our data, suggesting that this may depend on whether one is a small or a large blinker.The use of pupil dilation deconvolution seems to be a powerful approach to study the temporal dynamics of attention, bringing us a step closer to understanding the elusive nature of the AB. We conclude that the timing of attention to targets may be more important than the amount of allocated attention in accounting for individual differences.

  19. Explaining climate danger

    Science.gov (United States)

    Oreskes, N.

    2016-12-01

    The idea of `managing planet Earth' is traceable back at least to the 1970s. Recently, it has been reformulated in the idea of a "good Anthropocene": the idea that humans should and can try to manage our planet now that we have become a planetary force. Yet available evidence and experience suggests that our prior attempts to do so have been plagued by under-estimation of the scale of the problems and over-estimation of our capacities to address them. In any case, Earth is not at risk—our planet will survive despite what we do or fail to do. Global climate change, for example, is not a problem for the planet, it is a problem for us. As the UNFCCC articulated in the 1990s, climate change matters because it is dangerous. Yet many Americans still do not understand why this is the case. I suggest that scientists can profitably fo