WorldWideScience

Sample records for body size functional

  1. The non-linear relationship between body size and function in parrotfishes

    Science.gov (United States)

    Lokrantz, J.; Nyström, M.; Thyresson, M.; Johansson, C.

    2008-12-01

    Parrotfishes are a group of herbivores that play an important functional role in structuring benthic communities on coral reefs. Increasingly, these fish are being targeted by fishermen, and resultant declines in biomass and abundance may have severe consequences for the dynamics and regeneration of coral reefs. However, the impact of overfishing extends beyond declining fish stocks. It can also lead to demographic changes within species populations where mean body size is reduced. The effect of reduced mean body size on population dynamics is well described in literature but virtually no information exists on how this may influence important ecological functions. The study investigated how one important function, scraping (i.e., the capacity to remove algae and open up bare substratum for coral larval settlement), by three common species of parrotfishes ( Scarus niger, Chlorurus sordidus, and Chlorurus strongylocephalus) on coral reefs at Zanzibar (Tanzania) was influenced by the size of individual fishes. There was a non-linear relationship between body size and scraping function for all species examined, and impact through scraping was also found to increase markedly when fish reached a size of 15 20 cm. Thus, coral reefs which have a high abundance and biomass of parrotfish may nonetheless be functionally impaired if dominated by small-sized individuals. Reductions in mean body size within parrotfish populations could, therefore, have functional impacts on coral reefs that previously have been overlooked.

  2. Migrate small, sound big: functional constraints on body size promote tracheal elongation in cranes.

    Science.gov (United States)

    Jones, M R; Witt, C C

    2014-06-01

    Organismal traits often represent the outcome of opposing selection pressures. Although social or sexual selection can cause the evolution of traits that constrain function or survival (e.g. ornamental feathers), it is unclear how the strength and direction of selection respond to ecological shifts that increase the severity of the constraint. For example, reduced body size might evolve by natural selection to enhance flight performance in migratory birds, but social or sexual selection favouring large body size may provide a countervailing force. Tracheal elongation is a potential outcome of these opposing pressures because it allows birds to convey an auditory signal of exaggerated body size. We predicted that the evolution of migration in cranes has coincided with a reduction in body size and a concomitant intensification of social or sexual selection for apparent large body size via tracheal elongation. We used a phylogenetic comparative approach to examine the relationships among migration distance, body mass and trachea length in cranes. As predicted, we found that migration distance correlated negatively with body size and positively with proportional trachea length. This result was consistent with our hypothesis that evolutionary reductions in body size led to intensified selection for trachea length. The most likely ultimate causes of intensified positive selection on trachea length are the direct benefits of conveying a large body size in intraspecific contests for mates and territories. We conclude that the strength of social or sexual selection on crane body size is linked to the degree of functional constraint. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  3. Joint evolution of predator body size and prey-size preference.

    NARCIS (Netherlands)

    Troost, T.A.; Kooi, B.W.; Dieckmann, U.

    2007-01-01

    We studied the joint evolution of predator body size and prey-size preference based on dynamic energy budget theory. The predators' demography and their functional response are based on general eco-physiological principles involving the size of both predator and prey. While our model can account for

  4. Joint evolution of predator body size and prey-size preference

    NARCIS (Netherlands)

    Troost, Tineke; Kooi, Bob; Dieckmann, Ulf

    2007-01-01

    We studied the joint evolution of predator body size and prey-size preference based on dynamic energy budget theory. The predators’ demography and their functional response are based on general eco-physiological principles involving the size of both predator and prey. While our model can account

  5. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size

    OpenAIRE

    Kubo, Tai; Kubo, Mugino O.

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. Accordi...

  6. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size.

    Directory of Open Access Journals (Sweden)

    Tai Kubo

    Full Text Available Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade, yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals are above 500 g, except for macroscelid mammals (i.e., elephant shrew, a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs. When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope's rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna.

  7. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size.

    Science.gov (United States)

    Kubo, Tai; Kubo, Mugino O

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope's rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna.

  8. Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study

    OpenAIRE

    Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

    2015-01-01

    Introduction: Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. Aim: To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. Methods: An opportunistic sample of 90 men from the community were recru...

  9. Interspecific geographic range size-body size relationship and the diversification dynamics of Neotropical furnariid birds.

    Science.gov (United States)

    Inostroza-Michael, Oscar; Hernández, Cristián E; Rodríguez-Serrano, Enrique; Avaria-Llautureo, Jorge; Rivadeneira, Marcelo M

    2018-05-01

    Among the earliest macroecological patterns documented, is the range and body size relationship, characterized by a minimum geographic range size imposed by the species' body size. This boundary for the geographic range size increases linearly with body size and has been proposed to have implications in lineages evolution and conservation. Nevertheless, the macroevolutionary processes involved in the origin of this boundary and its consequences on lineage diversification have been poorly explored. We evaluate the macroevolutionary consequences of the difference (hereafter the distance) between the observed and the minimum range sizes required by the species' body size, to untangle its role on the diversification of a Neotropical species-rich bird clade using trait-dependent diversification models. We show that speciation rate is a positive hump-shaped function of the distance to the lower boundary. The species with highest and lowest distances to minimum range size had lower speciation rates, while species close to medium distances values had the highest speciation rates. Further, our results suggest that the distance to the minimum range size is a macroevolutionary constraint that affects the diversification process responsible for the origin of this macroecological pattern in a more complex way than previously envisioned. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

  10. Association between different phases of menstrual cycle and body image measures of perceived size, ideal size, and body dissatisfaction.

    Science.gov (United States)

    Teixeira, André Luiz S; Dias, Marcelo Ricardo C; Damasceno, Vinícius O; Lamounier, Joel A; Gardner, Rick M

    2013-12-01

    The association between phases of the menstrual cycle and body image was investigated. 44 university women (M age = 23.3 yr., SD = 4.7) judged their perceived and ideal body size, and body dissatisfaction was calculated at each phase of the menstrual cycle, including premenstrual, menstrual, and intermenstrual. Participants selected one of nine figural drawings ranging from very thin to obese that represented their perceived size and ideal size. Body dissatisfaction was measured as the absolute difference between scores on perceived and ideal figural drawings. During each menstrual phase, anthropometric measures of weight, height, body mass index, circumference of waist and abdomen, and body composition were taken. There were no significant differences in any anthropometric measures between the three menstrual cycle phases. Perceived body size and body dissatisfaction were significantly different between menstrual phases, with the largest perceived body size and highest body dissatisfaction occurring during the menstrual phase. Ideal body size did not differ between menstrual phases, although participants desired a significantly smaller ideal size as compared to the perceived size.

  11. The relations between forest fragmentation and bird community body size and biodiversity and bird community body size.

    OpenAIRE

    Hopman, F.

    2017-01-01

    Bachelor thesis Future Planet Studies, major biologie ABSTRACT Animal species with a larger body-size tend to have larger home ranges than small-bodied animals. Therefore it is likely that they are more affected by habitat fragmentation than small-bodied species. Body size of birds also seems to have a negative relation with species richness. This research has therefore looked into whether birds with a larger body-size are more sensitive to habitat fragmentation caused by forest...

  12. Explaining body size beliefs in anorexia.

    Science.gov (United States)

    Gadsby, Stephen

    2017-11-01

    Cognitive neuropsychiatry has had much success in providing theoretical models for the causal origins of many delusional beliefs. Recently, it has been suggested that some anorexia nervosa patients' beliefs about their own body size should be considered delusions. As such, it seems high time the methods of cognitive neuropsychiatry were turned to modelling the false body size beliefs of anorexics. In this paper, I adopt an empiricist approach to modelling the causal origins of false body size beliefs in anorexia. Within the background of cognitive neuropsychiatry, empiricist models claim that abnormal beliefs are grounded by abnormal experiences bearing similar content. I discuss the kinds of abnormal experiences of body size anorexics suffer from which could ground their false beliefs about body size. These oversized experiences come in three varieties: false self-other body comparisons, spontaneous mental imagery of a fat body and distorted perception of affordances. Further theoretical and empirical research into the oversized experiences which anorexics suffer from presents a promising avenue for understanding and treating the disorder.

  13. Evolution of body size in Galapagos marine iguanas.

    Science.gov (United States)

    Wikelski, Martin

    2005-10-07

    Body size is one of the most important traits of organisms and allows predictions of an individual's morphology, physiology, behaviour and life history. However, explaining the evolution of complex traits such as body size is difficult because a plethora of other traits influence body size. Here I review what we know about the evolution of body size in a group of island reptiles and try to generalize about the mechanisms that shape body size. Galapagos marine iguanas occupy all 13 larger islands in this Pacific archipelago and have maximum island body weights between 900 and 12 000g. The distribution of body sizes does not match mitochondrial clades, indicating that body size evolves independently of genetic relatedness. Marine iguanas lack intra- and inter-specific food competition and predators are not size-specific, discounting these factors as selective agents influencing body size. Instead I hypothesize that body size reflects the trade-offs between sexual and natural selection. We found that sexual selection continuously favours larger body sizes. Large males establish display territories and some gain over-proportional reproductive success in the iguanas' mating aggregations. Females select males based on size and activity and are thus responsible for the observed mating skew. However, large individuals are strongly selected against during El Niño-related famines when dietary algae disappear from the intertidal foraging areas. We showed that differences in algae sward ('pasture') heights and thermal constraints on large size are causally responsible for differences in maximum body size among populations. I hypothesize that body size in many animal species reflects a trade-off between foraging constraints and sexual selection and suggest that future research could focus on physiological and genetic mechanisms determining body size in wild animals. Furthermore, evolutionary stable body size distributions within populations should be analysed to better

  14. Temporal profile of body temperature in acute ischemic stroke: relation to infarct size and outcome.

    Science.gov (United States)

    Geurts, Marjolein; Scheijmans, Féline E V; van Seeters, Tom; Biessels, Geert J; Kappelle, L Jaap; Velthuis, Birgitta K; van der Worp, H Bart

    2016-11-21

    High body temperatures after ischemic stroke have been associated with larger infarct size, but the temporal profile of this relation is unknown. We assess the relation between temporal profile of body temperature and infarct size and functional outcome in patients with acute ischemic stroke. In 419 patients with acute ischemic stroke we assessed the relation between body temperature on admission and during the first 3 days with both infarct size and functional outcome. Infarct size was measured in milliliters on CT or MRI after 3 days. Poor functional outcome was defined as a modified Rankin Scale score ≥3 at 3 months. Body temperature on admission was not associated with infarct size or poor outcome in adjusted analyses. By contrast, each additional 1.0 °C in body temperature on day 1 was associated with 0.31 ml larger infarct size (95% confidence interval (CI) 0.04-0.59), on day 2 with 1.13 ml larger infarct size(95% CI, 0.83-1.43), and on day 3 with 0.80 ml larger infarct size (95% CI, 0.48-1.12), in adjusted linear regression analyses. Higher peak body temperatures on days two and three were also associated with poor outcome (adjusted relative risks per additional 1.0 °C in body temperature, 1.52 (95% CI, 1.17-1.99) and 1.47 (95% CI, 1.22-1.77), respectively). Higher peak body temperatures during the first days after ischemic stroke, rather than on admission, are associated with larger infarct size and poor functional outcome. This suggests that prevention of high temperatures may improve outcome if continued for at least 3 days.

  15. Optimum body size of Holstein replacement heifers.

    Science.gov (United States)

    Hoffman, P C

    1997-03-01

    Criteria that define optimum body size of replacement heifers are required by commercial dairy producers to evaluate replacement heifer management programs. Historically recommended body size criteria have been based on live BW measurements. Numerous research studies have observed a positive relationship between BW at first calving and first lactation milk yield, which has served as the impetus for using live BW to define body size of replacement heifers. Live BW is, however, not the only available measurement to define body size. Skeletal measurements such as wither height, length, and pelvic area have been demonstrated to be related to first lactation performance and (or) dystocia. Live BW measurements also do not define differences in body composition. Differences in body composition of replacement heifers at first calving are also related to key performance variables. An updated research data base is available for the modern Holstein genotype to incorporate measures of skeletal growth and body composition with BW when defining body size. These research projects also lend insight into the relative importance of measurements that define body size of replacement heifers. Incorporation of these measurements from current research into present BW recommendations should aid commercial dairy producers to better define replacement heifer growth and management practices. This article proposes enhancements in defining optimum body size and growth characteristics of Holstein replacement heifers.

  16. Detecting size and shape of bodies capacitatively

    International Nuclear Information System (INIS)

    Walton, H.

    1980-01-01

    The size and shape of a body is determined by rolling it between the plates of capacitors and measuring the capacitance changes. A capacitor comprising two parallel, spaced wires inclined to the rolling direction and above and below the rolling body scans sections of the body along its longitudinal axis, another determines the body's lengths and a third comprising two non-parallel wires determines the position of the body. The capacitance changes are compared with those produced by a body of known size and shape so that the size and shape of the body can be determined. (author)

  17. Body Size, Extinction Risk and Knowledge Bias in New World Snakes

    Science.gov (United States)

    Vilela, Bruno; Villalobos, Fabricio; Rodríguez, Miguel Ángel; Terribile, Levi Carina

    2014-01-01

    Extinction risk and body size have been found to be related in various vertebrate groups, with larger species being more at risk than smaller ones. We checked whether this was also the case for snakes by investigating extinction risk–body size relationships in the New World's Colubroidea species. We used the IUCN Red List risk categories to assign each species to one of two broad levels of threat (Threatened and Non-Threatened) or to identify it as either Data Deficient or Not-Evaluated by the IUCN. We also included the year of description of each species in our analysis as this could affect the level of threat assigned to it (earlier described species had more time to gather information about them, which might have facilitated their evaluation). Also, species detectability could be a function of body size, with larger species tending to be described earlier, which could have an impact in extinction risk–body size relationships. We found a negative relationship between body size and description year, with large-bodied species being described earlier. Description year also varied among risk categories, with Non-Threatened species being described earlier than Threatened species and both species groups earlier than Data Deficient species. On average, Data Deficient species also presented smaller body sizes, while no size differences were detected between Threatened and Non-Threatened species. So it seems that smaller body sizes are related with species detectability, thus potentially affecting both when a species is described (smaller species tend to be described more recently) as well as the amount of information gathered about it (Data Deficient species tend to be smaller). Our data also indicated that if Data Deficient species were to be categorized as Threatened in the future, snake body size and extinction risk would be negatively related, contrasting with the opposite pattern commonly observed in other vertebrate groups. PMID:25409293

  18. The discrepancy between emotional vs. rational estimates of body size, actual size, and ideal body ratings: theoretical and clinical implications.

    Science.gov (United States)

    Thompson, J K; Dolce, J J

    1989-05-01

    Thirty-two asymptomatic college females were assessed on multiple aspects of body image. Subjects' estimation of the size of three body sites (waist, hips, thighs) was affected by instructional protocol. Emotional ratings, based on how they "felt" about their body, elicited ratings that were larger than actual and ideal size measures. Size ratings based on rational instructions were no different from actual sizes, but were larger than ideal ratings. There were no differences between actual and ideal sizes. The results are discussed with regard to methodological issues involved in body image research. In addition, a working hypothesis that differentiates affective/emotional from cognitive/rational aspects of body size estimation is offered to complement current theories of body image. Implications of the findings for the understanding of body image and its relationship to eating disorders are discussed.

  19. Decreases in beetle body size linked to climate change and warming temperatures.

    Science.gov (United States)

    Tseng, Michelle; Kaur, Katrina M; Soleimani Pari, Sina; Sarai, Karnjit; Chan, Denessa; Yao, Christine H; Porto, Paula; Toor, Anmol; Toor, Harpawantaj S; Fograscher, Katrina

    2018-05-01

    Body size is a fundamental ecological trait and is correlated with population dynamics, community structure and function, and ecosystem fluxes. Laboratory data from broad taxonomic groups suggest that a widespread response to a warming world may be an overall decrease in organism body size. However, given the myriad of biotic and abiotic factors that can also influence organism body size in the wild, it is unclear whether results from these laboratory assays hold in nature. Here we use datasets spanning 30 to 100 years to examine whether the body size of wild-caught beetles has changed over time, whether body size changes are correlated with increased temperatures, and we frame these results using predictions derived from a quantitative review of laboratory responses of 22 beetle species to temperature. We found that 95% of laboratory-reared beetles decreased in size with increased rearing temperature, with larger-bodied species shrinking disproportionately more than smaller-bodied beetles. In addition, the museum datasets revealed that larger-bodied beetle species have decreased in size over time, that mean beetle body size explains much of the interspecific variation in beetle responses to temperature, and that long-term beetle size changes are explained by increases in autumn temperature and decreases in spring temperature in this region. Our data demonstrate that the relationship between body size and temperature of wild-caught beetles matches relatively well with results from laboratory studies, and that variation in this relationship is largely explained by interspecific variation in mean beetle body size. This long-term beetle dataset is one of the most comprehensive arthropod body size datasets compiled to date, it improves predictions regarding the shrinking of organisms with global climate change, and together with the meta-analysis data, call for new hypotheses to explain why larger-bodied organisms may be more sensitive to temperature. © 2018 The

  20. Neural substrate of body size: illusory feeling of shrinking of the waist.

    Directory of Open Access Journals (Sweden)

    H Henrik Ehrsson

    2005-12-01

    Full Text Available The perception of the size and shape of one's body (body image is a fundamental aspect of how we experience ourselves. We studied the neural correlates underlying perceived changes in the relative size of body parts by using a perceptual illusion in which participants felt that their waist was shrinking. We scanned the brains of the participants using functional magnetic resonance imaging. We found that activity in the cortices lining the left postcentral sulcus and the anterior part of the intraparietal sulcus reflected the illusion of waist shrinking, and that this activity was correlated with the reported degree of shrinking. These results suggest that the perceived changes in the size and shape of body parts are mediated by hierarchically higher-order somatosensory areas in the parietal cortex. Based on this finding we suggest that relative size of body parts is computed by the integration of more elementary somatic signals from different body segments.

  1. Effects of exposure to bodies of different sizes on perception of and satisfaction with own body size: two randomized studies.

    Science.gov (United States)

    Bould, Helen; Carnegie, Rebecca; Allward, Heather; Bacon, Emily; Lambe, Emily; Sapseid, Megan; Button, Katherine S; Lewis, Glyn; Skinner, Andy; Broome, Matthew R; Park, Rebecca; Harmer, Catherine J; Penton-Voak, Ian S; Munafò, Marcus R

    2018-05-01

    Body dissatisfaction is prevalent among women and associated with subsequent obesity and eating disorders. Exposure to images of bodies of different sizes has been suggested to change the perception of 'normal' body size in others. We tested whether exposure to different-sized (otherwise identical) bodies changes perception of own and others' body size, satisfaction with body size and amount of chocolate consumed. In Study 1, 90 18-25-year-old women with normal BMI were randomized into one of three groups to complete a 15 min two-back task using photographs of women either of 'normal weight' (Body Mass Index (BMI) 22-23 kg m -2 ), or altered to appear either under- or over-weight. Study 2 was identical except the 96 participants had high baseline body dissatisfaction and were followed up after 24 h. We also conducted a mega-analysis combining both studies. Participants rated size of others' bodies, own size, and satisfaction with size pre- and post-task. Post-task ratings were compared between groups, adjusting for pre-task ratings. Participants exposed to over- or normal-weight images subsequently perceived others' bodies as smaller, in comparison to those shown underweight bodies ( p  < 0.001). They also perceived their own bodies as smaller (Study 1, p  = 0.073; Study 2, p  = 0.018; mega-analysis, p  = 0.001), and felt more satisfied with their size (Study 1, p  = 0.046; Study 2, p  = 0.004; mega-analysis, p  = 0.006). There were no differences in chocolate consumption. This study suggests that a move towards using images of women with a BMI in the healthy range in the media may help to reduce body dissatisfaction, and the associated risk of eating disorders.

  2. An assessment of body appreciation and its relationship to sexual function in women.

    Science.gov (United States)

    Satinsky, Sonya; Reece, Michael; Dennis, Barbara; Sanders, Stephanie; Bardzell, Shaowen

    2012-01-01

    Objectification theory posits internalization of an observer's gaze may negatively impact women's feelings about their bodies, which may subsequently affect their sexual function. Subjective body image and body size (i.e., body mass index [BMI]) have mixed relationships to women's sexuality, but assessment of positive body image as a sign of resistance to objectification has not been researched. This study explored relations between body appreciation and sexual function in women and assessed whether body size impacted this relationship. Cross-sectional data were collected online from 247 women, ages 18 to 58. Body appreciation scores were modestly negatively correlated with BMI, while BMI was not related to sexual function scores. After controlling for sexual orientation, partner status, and age, body appreciation predicted the arousal, orgasm, and satisfaction aspects of sexual function. Practitioners' encouragement of body appreciation may improve sexual function in a way that encouraging a reduction in body size may not. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Body size distribution of the dinosaurs.

    Directory of Open Access Journals (Sweden)

    Eoin J O'Gorman

    Full Text Available The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutionary pressures and adaptations? Here, we address this question by comparing the distribution of maximum species body size for dinosaurs to an extensive set of extant and extinct vertebrate groups. We also examine the body size distribution of dinosaurs by various sub-groups, time periods and formations. We find that dinosaurs exhibit a strong skew towards larger species, in direct contrast to modern day vertebrates. This pattern is not solely an artefact of bias in the fossil record, as demonstrated by contrasting distributions in two major extinct groups and supports the hypothesis that dinosaurs exhibited a fundamentally different life history strategy to other terrestrial vertebrates. A disparity in the size distribution of the herbivorous Ornithischia and Sauropodomorpha and the largely carnivorous Theropoda suggests that this pattern may have been a product of a divergence in evolutionary strategies: herbivorous dinosaurs rapidly evolved large size to escape predation by carnivores and maximise digestive efficiency; carnivores had sufficient resources among juvenile dinosaurs and non-dinosaurian prey to achieve optimal success at smaller body size.

  4. Body size distribution of the dinosaurs.

    Science.gov (United States)

    O'Gorman, Eoin J; Hone, David W E

    2012-01-01

    The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutionary pressures and adaptations? Here, we address this question by comparing the distribution of maximum species body size for dinosaurs to an extensive set of extant and extinct vertebrate groups. We also examine the body size distribution of dinosaurs by various sub-groups, time periods and formations. We find that dinosaurs exhibit a strong skew towards larger species, in direct contrast to modern day vertebrates. This pattern is not solely an artefact of bias in the fossil record, as demonstrated by contrasting distributions in two major extinct groups and supports the hypothesis that dinosaurs exhibited a fundamentally different life history strategy to other terrestrial vertebrates. A disparity in the size distribution of the herbivorous Ornithischia and Sauropodomorpha and the largely carnivorous Theropoda suggests that this pattern may have been a product of a divergence in evolutionary strategies: herbivorous dinosaurs rapidly evolved large size to escape predation by carnivores and maximise digestive efficiency; carnivores had sufficient resources among juvenile dinosaurs and non-dinosaurian prey to achieve optimal success at smaller body size.

  5. Body Size Distribution of the Dinosaurs

    Science.gov (United States)

    O’Gorman, Eoin J.; Hone, David W. E.

    2012-01-01

    The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutionary pressures and adaptations? Here, we address this question by comparing the distribution of maximum species body size for dinosaurs to an extensive set of extant and extinct vertebrate groups. We also examine the body size distribution of dinosaurs by various sub-groups, time periods and formations. We find that dinosaurs exhibit a strong skew towards larger species, in direct contrast to modern day vertebrates. This pattern is not solely an artefact of bias in the fossil record, as demonstrated by contrasting distributions in two major extinct groups and supports the hypothesis that dinosaurs exhibited a fundamentally different life history strategy to other terrestrial vertebrates. A disparity in the size distribution of the herbivorous Ornithischia and Sauropodomorpha and the largely carnivorous Theropoda suggests that this pattern may have been a product of a divergence in evolutionary strategies: herbivorous dinosaurs rapidly evolved large size to escape predation by carnivores and maximise digestive efficiency; carnivores had sufficient resources among juvenile dinosaurs and non-dinosaurian prey to achieve optimal success at smaller body size. PMID:23284818

  6. Artificial fish schools : Collective effects of school size, body size, and body form

    NARCIS (Netherlands)

    Kunz, H.; Hemelrijk, C.K.

    2003-01-01

    Individual-based models of schooling in fish have demonstrated that, via processes of self-organization. artificial fish may school in the absence of a leader or external stimuli, using local information only. We study for the first time how body size and body form of artificial fish affect school

  7. Size matters: relationships between body size and body mass of common coastal, aquatic invertebrates in the Baltic Sea

    Directory of Open Access Journals (Sweden)

    Johan Eklöf

    2017-01-01

    Full Text Available Background Organism biomass is one of the most important variables in ecological studies, making biomass estimations one of the most common laboratory tasks. Biomass of small macroinvertebrates is usually estimated as dry mass or ash-free dry mass (hereafter ‘DM’ vs. ‘AFDM’ per sample; a laborious and time consuming process, that often can be speeded up using easily measured and reliable proxy variables like body size or wet (fresh mass. Another common way of estimating AFDM (one of the most accurate but also time-consuming estimates of biologically active tissue mass is the use of AFDM/DM ratios as conversion factors. So far, however, these ratios typically ignore the possibility that the relative mass of biologically active vs. non-active support tissue (e.g., protective exoskeleton or shell—and therefore, also AFDM/DM ratios—may change with body size, as previously shown for taxa like spiders, vertebrates and trees. Methods We collected aquatic, epibenthic macroinvertebrates (>1 mm in 32 shallow bays along a 360 km stretch of the Swedish coast along the Baltic Sea; one of the largest brackish water bodies on Earth. We then estimated statistical relationships between the body size (length or height in mm, body dry mass and ash-free dry mass for 14 of the most common taxa; five gastropods, three bivalves, three crustaceans and three insect larvae. Finally, we statistically estimated the potential influence of body size on the AFDM/DM ratio per taxon. Results For most taxa, non-linear regression models describing the power relationship between body size and (i DM and (ii AFDM fit the data well (as indicated by low SE and high R2. Moreover, for more than half of the taxa studied (including the vast majority of the shelled molluscs, body size had a negative influence on organism AFDM/DM ratios. Discussion The good fit of the modelled power relationships suggests that the constants reported here can be used to quickly estimate

  8. Carotid body size on CTA: Correlation with comorbidities

    International Nuclear Information System (INIS)

    Cramer, J.A.; Wiggins, R.H.; Fudim, M.; Engelman, Z.J.; Sobotka, P.A.; Shah, L.M.

    2014-01-01

    Aim: To test the hypothesis that computed tomographic angiography (CTA) can identify carotid body enlargement in patients with sympathetically mediated diseases. Materials and methods: A retrospective chart review of all patients obtaining CTAs of the cervical vasculature at University of Utah Health Sciences Center over a 6-month period was performed. Widest axial measurements of both carotid bodies were performed on a picture archiving and communication system (PACS). Statistical analysis was then performed to compare the mean carotid body size between control patients and patients with diabetes mellitus, hypertension, and congestive heart failure. Results: Measurements were performed on 288 patients, with 134 controls. Of the remaining 154, 72 patients had diabetes mellitus, 46 had congestive heart failure, and 130 had hypertension. The control patients had a mean carotid body diameter of 2.3 mm. There was a statistically significant (p < 0.01) 20–25% increase in mean diameter with diabetes mellitus (2.8 mm), hypertension (2.7 mm), and congestive heart failure (2.7 mm; p < 0.01). Conclusions: This study found a 20–25% larger mean carotid body size in patients with diabetes mellitus, hypertension, and congestive heart failure relative to controls. However, this small enlargement should not mimic other carotid body diseases, such as a paraganglionoma. Moreover, these findings further support the proposed functional relationship between the carotid body and sympathetically mediated disease states

  9. Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study

    Directory of Open Access Journals (Sweden)

    David Veale, MD, FRCPsych

    2015-09-01

    Conclusion: Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures. Veale D, Miles S, Read J, Troglia A, Wylie K, and Muir G. Sexual functioning and behavior of men with body dysmorphic disorder concerning penis size compared with men anxious about penis size and with controls: A cohort study. Sex Med 2015;3:147–155.

  10. Muzzle size, paranasal swelling size and body mass in Mandrillus leucophaeus.

    Science.gov (United States)

    Elton, Sarah; Morgan, Bethan J

    2006-04-01

    The drill (Mandrillus leucophaeus), a forest-living Old World monkey, is highly sexually dimorphic, with males exhibiting extreme secondary sexual characteristics, including growth of paranasal swellings on the muzzle. In this study, the size of the secondary bone that forms the paranasal swellings on the muzzles of drills was assessed in relation to body mass proxies. The relationship between the overall size of the muzzle and surrogate measures of body mass was also examined. In female drills, muzzle breadth was positively correlated with two proxies of overall body mass, greatest skull length and upper M1 area. However, there was no such correlation in males. Paranasal swellings in males also appeared to have no significant relationship to body mass proxies. This suggests that secondary bone growth on the muzzles of male drills is independent of overall body size. Furthermore, this secondary bone appears to be vermiculate, probably developing rapidly and in an irregular manner, with no correlation in the sizes of paranasal swelling height and breadth. However, various paranasal swelling dimensions were related to the size of the muzzle. It is suggested that the growth of the paranasal swellings and possibly the muzzle could be influenced by androgen production and reflect testes size and sperm motility. The size and appearance of the paranasal swellings may thus be an indicator of reproductive quality both to potential mates and male competitors. Further work is required to investigate the importance of the paranasal swellings as secondary sexual characteristics in Mandrillus and the relationship between body size and secondary sexual characteristics. Attention should also be paid to the mechanisms and trajectories of facial growth in Mandrillus.

  11. Climate change and body size shift in Mediterranean bivalve assemblages: unexpected role of biological invasions.

    Science.gov (United States)

    Nawrot, Rafał; Albano, Paolo G; Chattopadhyay, Devapriya; Zuschin, Martin

    2017-08-16

    Body size is a synthetic functional trait determining many key ecosystem properties. Reduction in average body size has been suggested as one of the universal responses to global warming in aquatic ecosystems. Climate change, however, coincides with human-enhanced dispersal of alien species and can facilitate their establishment. We address effects of species introductions on the size structure of recipient communities using data on Red Sea bivalves entering the Mediterranean Sea through the Suez Canal. We show that the invasion leads to increase in median body size of the Mediterranean assemblage. Alien species are significantly larger than native Mediterranean bivalves, even though they represent a random subset of the Red Sea species with respect to body size. The observed patterns result primarily from the differences in the taxonomic composition and body-size distributions of the source and recipient species pools. In contrast to the expectations based on the general temperature-size relationships in marine ectotherms, continued warming of the Mediterranean Sea indirectly leads to an increase in the proportion of large-bodied species in bivalve assemblages by accelerating the entry and spread of tropical aliens. These results underscore complex interactions between changing climate and species invasions in driving functional shifts in marine ecosystems. © 2017 The Author(s).

  12. Evolution of bill size in relation to body size in toucans and hornbills (Aves: Piciformes and Bucerotiformes

    Directory of Open Access Journals (Sweden)

    Austin L. Hughes

    2014-06-01

    Full Text Available Evidence that the bill of the Toco Toucan, Ramphastos toco Statius Muller, 1776, has a specialized role in heat dissipation suggests a new function for the large and light-weight bill of the toucan family (Piciformes: Ramphastidae. A prediction of this hypothesis is that bill length in toucans will increase with body mass at a rate greater than the isometric expectation. This hypothesis was tested in a phylogenetic context with measurements of skeletal elements in adult males of 21 toucan species. In these species, 64.3% of variance in relative skeletal measurements was accounted for by the contrast between bill and body size. Maxilla length and depth increased with body mass at a greater than isometric rate relative to both body mass and other linear skeletal measures. By contrast, no such trend was seen in a parallel analysis of 24 hornbill species (Bucerotiformes, sometimes considered ecological equivalents of toucans. The unique relationship between bill size and body mass in toucans supports the hypothesis that the evolution of a heat dissipation function has been a persistent theme of bill evolution in toucans.

  13. Sauropod dinosaurs evolved moderately sized genomes unrelated to body size.

    Science.gov (United States)

    Organ, Chris L; Brusatte, Stephen L; Stein, Koen

    2009-12-22

    Sauropodomorph dinosaurs include the largest land animals to have ever lived, some reaching up to 10 times the mass of an African elephant. Despite their status defining the upper range for body size in land animals, it remains unknown whether sauropodomorphs evolved larger-sized genomes than non-avian theropods, their sister taxon, or whether a relationship exists between genome size and body size in dinosaurs, two questions critical for understanding broad patterns of genome evolution in dinosaurs. Here we report inferences of genome size for 10 sauropodomorph taxa. The estimates are derived from a Bayesian phylogenetic generalized least squares approach that generates posterior distributions of regression models relating genome size to osteocyte lacunae volume in extant tetrapods. We estimate that the average genome size of sauropodomorphs was 2.02 pg (range of species means: 1.77-2.21 pg), a value in the upper range of extant birds (mean = 1.42 pg, range: 0.97-2.16 pg) and near the average for extant non-avian reptiles (mean = 2.24 pg, range: 1.05-5.44 pg). The results suggest that the variation in size and architecture of genomes in extinct dinosaurs was lower than the variation found in mammals. A substantial difference in genome size separates the two major clades within dinosaurs, Ornithischia (large genomes) and Saurischia (moderate to small genomes). We find no relationship between body size and estimated genome size in extinct dinosaurs, which suggests that neutral forces did not dominate the evolution of genome size in this group.

  14. Body Size Distribution of the Dinosaurs

    OpenAIRE

    O?Gorman, Eoin J.; Hone, David W. E.

    2012-01-01

    The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutiona...

  15. Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study.

    Science.gov (United States)

    Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

    2015-09-01

    Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures.

  16. Oocyte size, egg index, and body lipid content in relation to body size in the solitary bee Megachile rotundata.

    Science.gov (United States)

    O'Neill, Kevin M; Delphia, Casey M; O'Neill, Ruth P

    2014-01-01

    Females of solitary, nest-provisioning bees have relatively low fecundity, but produce large eggs as part of their overall strategy of investing substantially in each offspring. In intraspecific comparisons of several species of solitary, nest-provisioning bees and wasps, the size of the mature eggs produced increases with female body size. We further examined oocyte size-body size correlations in the solitary bee Megachile rotundata (F.), an important crop pollinator. We hypothesized that larger females carry larger basal oocytes (i.e., those next in line to be oviposited) but that body size-oocyte size correlations would be absent soon after emergence, before their first eggs fully matured. Because egg production is likely affected by the quantity of stored lipids carried over from the bees' immature stages, we also tested the hypothesis that female body size is correlated with the body lipid content at adult emergence, the time during which oocyte growth accelerates. We found significant correlations of body size with oocyte size variables chosen to reflect: (1) the magnitude of the investment in the next egg to be laid (i.e., the length and volume of the basal oocyte) and (2) the longer term potential to produce mature oocytes (i.e., the summed lengths and volumes of the three largest oocytes in each female). Positive correlations existed throughout the nesting season, even during the first week following adult emergence. The ability to produce and carry larger oocytes may be linked to larger females starting the nesting season with greater lipid stores (which we document here) or to greater space within the abdomen of larger females. Compared to other species of solitary bees, M. rotundata appears to have (1) smaller oocytes than solitary nest-provisioning bees in general, (2) comparable oocyte sizes relative to congeners, and (3) larger oocytes than related brood parasitic megachilids.

  17. Distribution functions of sections and projections of convex bodies

    OpenAIRE

    Kim, Jaegil; Yaskin, Vladyslav; Zvavitch, Artem

    2015-01-01

    Typically, when we are given the section (or projection) function of a convex body, it means that in each direction we know the size of the central section (or projection) perpendicular to this direction. Suppose now that we can only get the information about the sizes of sections (or projections), and not about the corresponding directions. In this paper we study to what extent the distribution function of the areas of central sections (or projections) of a convex body can be used to derive ...

  18. Temporal profile of body temperature in acute ischemic stroke: Relation to infarct size and outcome

    NARCIS (Netherlands)

    M. Geurts (Marjolein); Scheijmans, F.E.V. (Féline E.V.); T. van Seeters (Tom); G.J. Biessels; L.J. Kappelle (Jaap); B.K. Velthuis (Birgitta K.); H.B. van der Worp (Bart); C.B. Majoie (Charles); Y.B.W.E.M. Roos (Yvo); L.E.M. Duijm (Lucien); K. Keizer (Koos); A. van der Lugt (Aad); D.W.J. Dippel (Diederik); Greve, D. (Droogh-de); H.P. Bienfait (Henri); M.A.A. van Walderveen (Marianne); M.J.H. Wermer (Marieke); G.J. Lycklama à Nijeholt (Geert); J. Boiten (Jelis); A. Duyndam (Anita); V.I.H. Kwa; F.J. Meijer (F.); E.J. van Dijk (Ewoud); A.M. Kesselring (Anouk); J. Hofmeijer; J.A. Vos (Jan Albert); W.J. Schonewille (Wouter); W.J. van Rooij (W.); P.L.M. de Kort (Paul); C.C. Pleiter (C.); S.L.M. Bakker (Stef); Bot, J.; M.C. Visser (Marieke); B.K. Velthuis (Birgitta); I.C. van der Schaaf (Irene); J.W. Dankbaar (Jan); W.P. Mali (Willem); van Seeters, T.; A.D. Horsch (Alexander D.); J.M. Niesten (Joris); G.J. Biessels (Geert Jan); L.J. Kappelle (Jaap); J.S.K. Luitse; Y. van der Graaf (Yolanda)

    2016-01-01

    textabstractBackground: High body temperatures after ischemic stroke have been associated with larger infarct size, but the temporal profile of this relation is unknown. We assess the relation between temporal profile of body temperature and infarct size and functional outcome in patients with acute

  19. Geographical variation in body size and sexual size dimorphism in an Australian lizard, Boulenger's Skink (Morethia boulengeri).

    Science.gov (United States)

    Michael, Damian R; Banks, Sam C; Piggott, Maxine P; Cunningham, Ross B; Crane, Mason; MacGregor, Christopher; McBurney, Lachlan; Lindenmayer, David B

    2014-01-01

    Ecogeographical rules help explain spatial and temporal patterns in intraspecific body size. However, many of these rules, when applied to ectothermic organisms such as reptiles, are controversial and require further investigation. To explore factors that influence body size in reptiles, we performed a heuristic study to examine body size variation in an Australian lizard, Boulenger's Skink Morethia boulengeri from agricultural landscapes in southern New South Wales, south-eastern Australia. We collected tissue and morphological data on 337 adult lizards across a broad elevation and climate gradient. We used a model-selection procedure to determine if environmental or ecological variables best explained body size variation. We explored the relationship between morphology and phylogenetic structure before modeling candidate variables from four broad domains: (1) geography (latitude, longitude and elevation), (2) climate (temperature and rainfall), (3) habitat (vegetation type, number of logs and ground cover attributes), and (4) management (land use and grazing history). Broad phylogenetic structure was evident, but on a scale larger than our study area. Lizards were sexually dimorphic, whereby females had longer snout-vent length than males, providing support for the fecundity selection hypothesis. Body size variation in M. boulengeri was correlated with temperature and rainfall, a pattern consistent with larger individuals occupying cooler and more productive parts of the landscape. Climate change forecasts, which predict warmer temperature and increased aridity, may result in reduced lizard biomass and decoupling of trophic interactions with potential implications for community organization and ecosystem function.

  20. Body weight in relation to variation in body size of Oystercatchers Haematopus ostralegus

    NARCIS (Netherlands)

    Zwarts, L; Hulscher, JB; Koopman, K; Zegers, PM

    1996-01-01

    This paper analyses the relationships between body weight in the Oystercatcher and two measures of its body size, bill length and wing length. The weight variation between individuals due to differences in body size is nearly as large as the seasonal variation in body weight within individuals. Wing

  1. Effect of meal size and body size on specific dynamic action and gastric processing in decapod crustaceans.

    Science.gov (United States)

    McGaw, Iain J; Curtis, Daniel L

    2013-11-01

    Meal size and animal size are important factors affecting the characteristics of the specific dynamic action (SDA) response across a variety of taxa. The effects of these two variables on the SDA of decapod crustaceans are based on just a couple of articles, and are not wholly consistent with the responses reported for other aquatic ectotherms. Therefore, the effects of meal size and animal size on the characteristics of SDA response were investigated in a variety of decapod crustaceans from different families. A 6 fold increase in meal size (0.5%-3% body mass) resulted a pronounced increase in the duration of increased oxygen consumption, resulting in an increase in the SDA of Callinectes sapidus, Cancer gracilis, Hemigrapsus nudus, Homarus americanus, Pugettia producta and Procambarus clarkii. Unlike many other aquatic ectotherms a substantial increase between meal sizes was required, with meal size close to their upper feeding limit (3% body mass), before changes were evident. In many organisms increases in both duration and scope contribute to the overall SDA, here changes in scope as a function of meal size were weak, suggesting that a similar amount of energy is required to upregulate gastric processes, regardless of meal size. The SDA characteristics were less likely to be influenced by the size of the animal, and there was no difference in the SDA (kJ) as a function of size in H. americanus or Cancer irroratus when analysed as mass specific values. In several fish species characteristics of the SDA response are more closely related to the transit times of food, rather than the size of a meal. To determine if a similar trend occurred in crustaceans, the transit rates of different sized meals were followed through the digestive system using a fluoroscope. Although there was a trend towards larger meals taking longer to pass through the gut, this was only statistically significant for P. clarkii. There were some changes in transit times as a function of animal

  2. Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study

    Science.gov (United States)

    Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

    2015-01-01

    Introduction Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. Aim To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. Methods An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). Main Outcome Measures The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Results Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Conclusion Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures. PMID:26468378

  3. Sneaker Males Affect Fighter Male Body Size and Sexual Size Dimorphism in Salmon.

    Science.gov (United States)

    Weir, Laura K; Kindsvater, Holly K; Young, Kyle A; Reynolds, John D

    2016-08-01

    Large male body size is typically favored by directional sexual selection through competition for mates. However, alternative male life-history phenotypes, such as "sneakers," should decrease the strength of sexual selection acting on body size of large "fighter" males. We tested this prediction with salmon species; in southern populations, where sneakers are common, fighter males should be smaller than in northern populations, where sneakers are rare, leading to geographical clines in sexual size dimorphism (SSD). Consistent with our prediction, fighter male body size and SSD (fighter male∶female size) increase with latitude in species with sneaker males (Atlantic salmon Salmo salar and masu salmon Oncorhynchus masou) but not in species without sneakers (chum salmon Oncorhynchus keta and pink salmon Oncorhynchus gorbuscha). This is the first evidence that sneaker males affect SSD across populations and species, and it suggests that alternative male mating strategies may shape the evolution of body size.

  4. Oocyte size, egg index, and body lipid content in relation to body size in the solitary bee Megachile rotundata

    Directory of Open Access Journals (Sweden)

    Kevin M. O’Neill

    2014-03-01

    Full Text Available Females of solitary, nest-provisioning bees have relatively low fecundity, but produce large eggs as part of their overall strategy of investing substantially in each offspring. In intraspecific comparisons of several species of solitary, nest-provisioning bees and wasps, the size of the mature eggs produced increases with female body size. We further examined oocyte size–body size correlations in the solitary bee Megachile rotundata (F., an important crop pollinator. We hypothesized that larger females carry larger basal oocytes (i.e., those next in line to be oviposited but that body size–oocyte size correlations would be absent soon after emergence, before their first eggs fully matured. Because egg production is likely affected by the quantity of stored lipids carried over from the bees’ immature stages, we also tested the hypothesis that female body size is correlated with the body lipid content at adult emergence, the time during which oocyte growth accelerates. We found significant correlations of body size with oocyte size variables chosen to reflect: (1 the magnitude of the investment in the next egg to be laid (i.e., the length and volume of the basal oocyte and (2 the longer term potential to produce mature oocytes (i.e., the summed lengths and volumes of the three largest oocytes in each female. Positive correlations existed throughout the nesting season, even during the first week following adult emergence. The ability to produce and carry larger oocytes may be linked to larger females starting the nesting season with greater lipid stores (which we document here or to greater space within the abdomen of larger females. Compared to other species of solitary bees, M. rotundata appears to have (1 smaller oocytes than solitary nest-provisioning bees in general, (2 comparable oocyte sizes relative to congeners, and (3 larger oocytes than related brood parasitic megachilids.

  5. Song repertoire size correlates with measures of body size in Eurasian blackbirds

    DEFF Research Database (Denmark)

    Hesler, Nana; Mundry, Roger; Sacher, Thomas

    2012-01-01

    In most oscine bird species males possess a repertoire of different song patterns. The size of these repertoires is assumed to serve as an honest signal of male quality. The Eurasian blackbird’s (Turdus merula) song contains a large repertoire of different element types with a flexible song...... organisation. Here we investigated whether repertoire size in Eurasian blackbirds correlates with measures of body size, namely length of wing, 8th primary, beak and tarsus. So far, very few studies have investigated species with large repertoires and a flexible song organisation in this context. We found...... positive correlations, meaning that larger males had larger repertoires. Larger males may have better fighting abilities and, thus, advantages in territorial defence. Larger structural body size may also reflect better conditions during early development. Therefore, under the assumption that body size...

  6. Body Size, Fecundity, and Sexual Size Dimorphism in the Neotropical Cricket Macroanaxipha macilenta (Saussure) (Orthoptera: Gryllidae).

    Science.gov (United States)

    Cueva Del Castillo, R

    2015-04-01

    Body size is directly or indirectly correlated with fitness. Body size, which conveys maximal fitness, often differs between sexes. Sexual size dimorphism (SSD) evolves because body size tends to be related to reproductive success through different pathways in males and females. In general, female insects are larger than males, suggesting that natural selection for high female fecundity could be stronger than sexual selection in males. I assessed the role of body size and fecundity in SSD in the Neotropical cricket Macroanaxipha macilenta (Saussure). This species shows a SSD bias toward males. Females did not present a correlation between number of eggs and body size. Nonetheless, there were fluctuations in the number of eggs carried by females during the sampling period, and the size of females that were collected carrying eggs was larger than that of females collected with no eggs. Since mating induces vitellogenesis in some cricket species, differences in female body size might suggest male mate choice. Sexual selection in the body size of males of M. macilenta may possibly be stronger than the selection of female fecundity. Even so, no mating behavior was observed during the field observations, including audible male calling or courtship songs, yet males may produce ultrasonic calls due to their size. If female body size in M. macilenta is not directly related to fecundity, the lack of a correlated response to selection on female body size could represent an alternate evolutionary pathway in the evolution of body size and SSD in insects.

  7. Body size, energy use, and community structure of small mammals

    OpenAIRE

    Ernest, S.K. Morgan

    2005-01-01

    Body size has long been hypothesized to play a major role in community structure and dynamics. Two general hypotheses exist for how resources are distributed among body sizes: (1) resources are equally available and uniformly utilized across body sizes and (2) resources are differentially available to organisms of different body sizes, resulting in a nonuniform or modal distribution. It has also been predicted that the distri-bution of body sizes of species in a community should reflect the u...

  8. How acoustic signals scale with individual body size: common trends across diverse taxa

    OpenAIRE

    Rafael L. Rodríguez; Marcelo Araya-Salas; David A. Gray; Michael S. Reichert; Laurel B. Symes; Matthew R. Wilkins; Rebecca J. Safran; Gerlinde Höbel

    2015-01-01

    We use allometric analysis to explore how acoustic signals scale on individual body size and to test hypotheses about the factors shaping relationships between signals and body size. Across case studies spanning birds, crickets, tree crickets, and tree frogs, we find that most signal traits had low coefficients of variation, shallow allometric scalings, and little dispersion around the allometric function. We relate variation in these measures to the shape of mate preferences and the level of...

  9. Association between inaccurate estimation of body size and obesity in schoolchildren

    Directory of Open Access Journals (Sweden)

    Larissa da Cunha Feio Costa

    2015-12-01

    Full Text Available Objectives: To investigate the prevalence of inaccurate estimation of own body size among Brazilian schoolchildren of both sexes aged 7-10 years, and to test whether overweight/obesity; excess body fat and central obesity are associated with inaccuracy. Methods: Accuracy of body size estimation was assessed using the Figure Rating Scale for Brazilian Children. Multinomial logistic regression was used to analyze associations. Results: The overall prevalence of inaccurate body size estimation was 76%, with 34% of the children underestimating their body size and 42% overestimating their body size. Obesity measured by body mass index was associated with underestimation of body size in both sexes, while central obesity was only associated with overestimation of body size among girls. Conclusions: The results of this study suggest there is a high prevalence of inaccurate body size estimation and that inaccurate estimation is associated with obesity. Accurate estimation of own body size is important among obese schoolchildren because it may be the first step towards adopting healthy lifestyle behaviors.

  10. Investigating Young Children's Perceptions of Body Size and Healthy Habits

    Science.gov (United States)

    Xu, Tingting; Nerren, Jannah S.

    2017-01-01

    Attitudes and biases toward body size perceived as fat and body size perceived as thin are present in young children (Cramer and Steinwert in "J Appl Dev Psychol" 19(3):429-451, 1998; Worobey and Worobey in "Body Image" 11:171-174, 2014). However, the information children have regarding body size and ways to modify body size…

  11. Latitudinal clines in Drosophila melanogaster: body size, allozyme ...

    Indian Academy of Sciences (India)

    Unknown

    logy, in explaining such natural genetic variation in D. melanogaster body size and development time. It is argued .... high latitudes were found to use limited food more effi- ciently, so ..... always associate fast development with small body size.

  12. Body size in early life and risk of breast cancer.

    Science.gov (United States)

    Shawon, Md Shajedur Rahman; Eriksson, Mikael; Li, Jingmei

    2017-07-21

    Body size in early life is inversely associated with adult breast cancer (BC) risk, but it is unclear whether the associations differ by tumor characteristics. In a pooled analysis of two Swedish population-based studies consisting of 6731 invasive BC cases and 28,705 age-matched cancer-free controls, we examined the associations between body size in early life and BC risk. Self-reported body sizes at ages 7 and 18 years were collected by a validated nine-level pictogram (aggregated into three categories: small, medium and large). Odds ratios (OR) and corresponding 95% confidence intervals (CI) were estimated from multivariable logistic regression models in case-control analyses, adjusting for study, age at diagnosis, age at menarche, number of children, hormone replacement therapy, and family history of BC. Body size change between ages 7 and 18 were also examined in relation to BC risk. Case-only analyses were performed to test whether the associations differed by tumor characteristics. Medium or large body size at age 7 and 18 was associated with a statistically significant decreased BC risk compared to small body size (pooled OR (95% CI): comparing large to small, 0.78 (0.70-0.86), P trend <0.001 and 0.72 (0.64-0.80), P trend <0.001, respectively). The majority of the women (~85%) did not change body size categories between age 7 and 18 . Women who remained medium or large between ages 7 and 18 had significantly decreased BC risk compared to those who remained small. A reduction in body size between ages 7 and 18 was also found to be inversely associated with BC risk (0.90 (0.81-1.00)). No significant association was found between body size at age 7 and tumor characteristics. Body size at age 18 was found to be inversely associated with tumor size (P trend  = 0.006), but not estrogen receptor status and lymph node involvement. For all analyses, the overall inferences did not change appreciably after further adjustment for adult body mass index. Our data

  13. Body size and lean mass of brown bears across and within four diverse ecosystems

    Science.gov (United States)

    Hilderbrand, Grant V.; Gustine, David; Mangipane, Buck A.; Joly, Kyle; Leacock, William; Mangipane, Lindsey S.; Erlenbach, Joy; Sorum, Mathew; Cameron, Matthew; Belant, Jerrold L.; Cambier, Troy

    2018-01-01

    Variation in body size across populations of brown bears (Ursus arctos) is largely a function of the availability and quality of nutritional resources while plasticity within populations reflects utilized niche width with implications for population resiliency. We assessed skull size, body length, and lean mass of adult female and male brown bears in four Alaskan study areas that differed in climate, primary food resources, population density, and harvest regime. Full body-frame size, as evidenced by asymptotic skull size and body length, was achieved by 8 to 14 years of age across populations and sexes. Lean body mass of both sexes continued to increase throughout their life. Differences between populations existed for all morphological measures in both sexes, bears in ecosystems with abundant salmon were generally larger. Within all populations, broad variation was seen in body size measures of adults with females displaying roughly a 2-fold difference in lean mass and males showing a 3- to 4-fold difference. The high level of intraspecific variation seen across and within populations suggests the presence of multiple life-history strategies and niche variation relative to resource partitioning, risk tolerance or aversion, and competition. Further, this level of variation indicates broad potential to adapt to changes within a given ecosystem and across the species’ range.

  14. Body size evolution in insular speckled rattlesnakes (Viperidae: Crotalus mitchellii.

    Directory of Open Access Journals (Sweden)

    Jesse M Meik

    2010-03-01

    Full Text Available Speckled rattlesnakes (Crotalus mitchellii inhabit multiple islands off the coast of Baja California, Mexico. Two of the 14 known insular populations have been recognized as subspecies based primarily on body size divergence from putative mainland ancestral populations; however, a survey of body size variation from other islands occupied by these snakes has not been previously reported. We examined body size variation between island and mainland speckled rattlesnakes, and the relationship between body size and various island physical variables among 12 island populations. We also examined relative head size among giant, dwarfed, and mainland speckled rattlesnakes to determine whether allometric differences conformed to predictions of gape size (and indirectly body size evolving in response to shifts in prey size.Insular speckled rattlesnakes show considerable variation in body size when compared to mainland source subspecies. In addition to previously known instances of gigantism on Angel de la Guarda and dwarfism on El Muerto, various degrees of body size decrease have occurred frequently in this taxon, with dwarfed rattlesnakes occurring mostly on small, recently isolated, land-bridge islands. Regression models using the Akaike information criterion (AIC showed that mean SVL of insular populations was most strongly correlated with island area, suggesting the influence of selection for different body size optima for islands of different size. Allometric differences in head size of giant and dwarf rattlesnakes revealed patterns consistent with shifts to larger and smaller prey, respectively.Our data provide the first example of a clear relationship between body size and island area in a squamate reptile species; among vertebrates this pattern has been previously documented in few insular mammals. This finding suggests that selection for body size is influenced by changes in community dynamics that are related to graded differences in area over

  15. Being Barbie: The Size of One’s Own Body Determines the Perceived Size of the World

    Science.gov (United States)

    van der Hoort, Björn; Guterstam, Arvid; Ehrsson, H. Henrik

    2011-01-01

    A classical question in philosophy and psychology is if the sense of one's body influences how one visually perceives the world. Several theoreticians have suggested that our own body serves as a fundamental reference in visual perception of sizes and distances, although compelling experimental evidence for this hypothesis is lacking. In contrast, modern textbooks typically explain the perception of object size and distance by the combination of information from different visual cues. Here, we describe full body illusions in which subjects experience the ownership of a doll's body (80 cm or 30 cm) and a giant's body (400 cm) and use these as tools to demonstrate that the size of one's sensed own body directly influences the perception of object size and distance. These effects were quantified in ten separate experiments with complementary verbal, questionnaire, manual, walking, and physiological measures. When participants experienced the tiny body as their own, they perceived objects to be larger and farther away, and when they experienced the large-body illusion, they perceived objects to be smaller and nearer. Importantly, despite identical retinal input, this “body size effect” was greater when the participants experienced a sense of ownership of the artificial bodies compared to a control condition in which ownership was disrupted. These findings are fundamentally important as they suggest a causal relationship between the representations of body space and external space. Thus, our own body size affects how we perceive the world. PMID:21633503

  16. Overestimation of body size in eating disorders and its association to body-related avoidance behavior.

    Science.gov (United States)

    Vossbeck-Elsebusch, Anna N; Waldorf, Manuel; Legenbauer, Tanja; Bauer, Anika; Cordes, Martin; Vocks, Silja

    2015-06-01

    Body-related avoidance behavior, e.g., not looking in the mirror, is a common feature of eating disorders. It is assumed that it leads to insufficient feedback concerning one's own real body form and might thus contribute to distorted mental representation of one's own body. However, this assumption still lacks empirical foundation. Therefore, the aim of the present study was to examine the relationship between misperception of one's own body and body-related avoidance behavior in N = 78 female patients with Bulimia nervosa and eating disorder not otherwise specified. Body-size misperception was assessed using a digital photo distortion technique based on an individual picture of each participant which was taken in a standardized suit. In a regression analysis with body-related avoidance behavior, body mass index and weight and shape concerns as predictors, only body-related avoidance behavior significantly contributed to the explanation of body-size overestimation. This result supports the theoretical assumption that body-related avoidance behavior makes body-size overestimation more likely.

  17. Male songbird indicates body size with low-pitched advertising songs.

    Science.gov (United States)

    Hall, Michelle L; Kingma, Sjouke A; Peters, Anne

    2013-01-01

    Body size is a key sexually selected trait in many animal species. If size imposes a physical limit on the production of loud low-frequency sounds, then low-pitched vocalisations could act as reliable signals of body size. However, the central prediction of this hypothesis--that the pitch of vocalisations decreases with size among competing individuals--has limited support in songbirds. One reason could be that only the lowest-frequency components of vocalisations are constrained, and this may go unnoticed when vocal ranges are large. Additionally, the constraint may only be apparent in contexts when individuals are indeed advertising their size. Here we explicitly consider signal diversity and performance limits to demonstrate that body size limits song frequency in an advertising context in a songbird. We show that in purple-crowned fairy-wrens, Malurus coronatus coronatus, larger males sing lower-pitched low-frequency advertising songs. The lower frequency bound of all advertising song types also has a significant negative relationship with body size. However, the average frequency of all their advertising songs is unrelated to body size. This comparison of different approaches to the analysis demonstrates how a negative relationship between body size and song frequency can be obscured by failing to consider signal design and the concept of performance limits. Since these considerations will be important in any complex communication system, our results imply that body size constraints on low-frequency vocalisations could be more widespread than is currently recognised.

  18. Male songbird indicates body size with low-pitched advertising songs.

    Directory of Open Access Journals (Sweden)

    Michelle L Hall

    Full Text Available Body size is a key sexually selected trait in many animal species. If size imposes a physical limit on the production of loud low-frequency sounds, then low-pitched vocalisations could act as reliable signals of body size. However, the central prediction of this hypothesis--that the pitch of vocalisations decreases with size among competing individuals--has limited support in songbirds. One reason could be that only the lowest-frequency components of vocalisations are constrained, and this may go unnoticed when vocal ranges are large. Additionally, the constraint may only be apparent in contexts when individuals are indeed advertising their size. Here we explicitly consider signal diversity and performance limits to demonstrate that body size limits song frequency in an advertising context in a songbird. We show that in purple-crowned fairy-wrens, Malurus coronatus coronatus, larger males sing lower-pitched low-frequency advertising songs. The lower frequency bound of all advertising song types also has a significant negative relationship with body size. However, the average frequency of all their advertising songs is unrelated to body size. This comparison of different approaches to the analysis demonstrates how a negative relationship between body size and song frequency can be obscured by failing to consider signal design and the concept of performance limits. Since these considerations will be important in any complex communication system, our results imply that body size constraints on low-frequency vocalisations could be more widespread than is currently recognised.

  19. Insect temperature-body size trends common to laboratory, latitudinal and seasonal gradients are not found across altitudes

    DEFF Research Database (Denmark)

    Horne, Curtis R.; Hirst, Andrew G.; Atkinson, David

    2018-01-01

    Body size affects rates of most biological and ecological processes, from individual performance to ecosystem function, and is fundamentally linked to organism fitness. Within species, size at maturity can vary systematically with environmental temperature in the laboratory and across seasons...... altitude. Although the general direction of body size clines along altitudinal gradients has been examined previously, to our knowledge altitude-body size (A-S) clines have never been synthesised quantitatively, nor compared with temperature-size (T-S) responses measured under controlled laboratory......, as well as over latitudinal gradients. Recent meta-analyses have revealed a close match in the magnitude and direction of these size gradients in various arthropod orders, suggesting that these size responses share common drivers. As with increasing latitude, temperature also decreases with increasing...

  20. Body size estimation of self and others in females varying in BMI.

    Directory of Open Access Journals (Sweden)

    Anne Thaler

    Full Text Available Previous literature suggests that a disturbed ability to accurately identify own body size may contribute to overweight. Here, we investigated the influence of personal body size, indexed by body mass index (BMI, on body size estimation in a non-clinical population of females varying in BMI. We attempted to disentangle general biases in body size estimates and attitudinal influences by manipulating whether participants believed the body stimuli (personalized avatars with realistic weight variations represented their own body or that of another person. Our results show that the accuracy of own body size estimation is predicted by personal BMI, such that participants with lower BMI underestimated their body size and participants with higher BMI overestimated their body size. Further, participants with higher BMI were less likely to notice the same percentage of weight gain than participants with lower BMI. Importantly, these results were only apparent when participants were judging a virtual body that was their own identity (Experiment 1, but not when they estimated the size of a body with another identity and the same underlying body shape (Experiment 2a. The different influences of BMI on accuracy of body size estimation and sensitivity to weight change for self and other identity suggests that effects of BMI on visual body size estimation are self-specific and not generalizable to other bodies.

  1. Body size estimation of self and others in females varying in BMI.

    Science.gov (United States)

    Thaler, Anne; Geuss, Michael N; Mölbert, Simone C; Giel, Katrin E; Streuber, Stephan; Romero, Javier; Black, Michael J; Mohler, Betty J

    2018-01-01

    Previous literature suggests that a disturbed ability to accurately identify own body size may contribute to overweight. Here, we investigated the influence of personal body size, indexed by body mass index (BMI), on body size estimation in a non-clinical population of females varying in BMI. We attempted to disentangle general biases in body size estimates and attitudinal influences by manipulating whether participants believed the body stimuli (personalized avatars with realistic weight variations) represented their own body or that of another person. Our results show that the accuracy of own body size estimation is predicted by personal BMI, such that participants with lower BMI underestimated their body size and participants with higher BMI overestimated their body size. Further, participants with higher BMI were less likely to notice the same percentage of weight gain than participants with lower BMI. Importantly, these results were only apparent when participants were judging a virtual body that was their own identity (Experiment 1), but not when they estimated the size of a body with another identity and the same underlying body shape (Experiment 2a). The different influences of BMI on accuracy of body size estimation and sensitivity to weight change for self and other identity suggests that effects of BMI on visual body size estimation are self-specific and not generalizable to other bodies.

  2. Spatial and temporal variation of body size among early Homo.

    Science.gov (United States)

    Will, Manuel; Stock, Jay T

    2015-05-01

    The estimation of body size among the earliest members of the genus Homo (2.4-1.5Myr [millions of years ago]) is central to interpretations of their biology. It is widely accepted that Homo ergaster possessed increased body size compared with Homo habilis and Homo rudolfensis, and that this may have been a factor involved with the dispersal of Homo out of Africa. The study of taxonomic differences in body size, however, is problematic. Postcranial remains are rarely associated with craniodental fossils, and taxonomic attributions frequently rest upon the size of skeletal elements. Previous body size estimates have been based upon well-preserved specimens with a more reliable species assessment. Since these samples are small (n Koobi Fora after 1.7Myr, indicating regional size variation. The significant body size differences between specimens from Koobi Fora and Olduvai support the cranial evidence for at least two co-existing morphotypes in the Early Pleistocene of eastern Africa. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Large-scale ocean connectivity and planktonic body size

    KAUST Repository

    Villarino, Ernesto; Watson, James R.; Jö nsson, Bror; Gasol, Josep M.; Salazar, Guillem; Acinas, Silvia G.; Estrada, Marta; Massana, Ramó n; Logares, Ramiro; Giner, Caterina R.; Pernice, Massimo C.; Olivar, M. Pilar; Citores, Leire; Corell, Jon; Rodrí guez-Ezpeleta, Naiara; Acuñ a, José Luis; Molina-Ramí rez, Axayacatl; Gonzá lez-Gordillo, J. Ignacio; Có zar, André s; Martí , Elisa; Cuesta, José A.; Agusti, Susana; Fraile-Nuez, Eugenio; Duarte, Carlos M.; Irigoien, Xabier; Chust, Guillem

    2018-01-01

    Global patterns of planktonic diversity are mainly determined by the dispersal of propagules with ocean currents. However, the role that abundance and body size play in determining spatial patterns of diversity remains unclear. Here we analyse spatial community structure - β-diversity - for several planktonic and nektonic organisms from prokaryotes to small mesopelagic fishes collected during the Malaspina 2010 Expedition. β-diversity was compared to surface ocean transit times derived from a global circulation model, revealing a significant negative relationship that is stronger than environmental differences. Estimated dispersal scales for different groups show a negative correlation with body size, where less abundant large-bodied communities have significantly shorter dispersal scales and larger species spatial turnover rates than more abundant small-bodied plankton. Our results confirm that the dispersal scale of planktonic and micro-nektonic organisms is determined by local abundance, which scales with body size, ultimately setting global spatial patterns of diversity.

  4. Large-scale ocean connectivity and planktonic body size

    KAUST Repository

    Villarino, Ernesto

    2018-01-04

    Global patterns of planktonic diversity are mainly determined by the dispersal of propagules with ocean currents. However, the role that abundance and body size play in determining spatial patterns of diversity remains unclear. Here we analyse spatial community structure - β-diversity - for several planktonic and nektonic organisms from prokaryotes to small mesopelagic fishes collected during the Malaspina 2010 Expedition. β-diversity was compared to surface ocean transit times derived from a global circulation model, revealing a significant negative relationship that is stronger than environmental differences. Estimated dispersal scales for different groups show a negative correlation with body size, where less abundant large-bodied communities have significantly shorter dispersal scales and larger species spatial turnover rates than more abundant small-bodied plankton. Our results confirm that the dispersal scale of planktonic and micro-nektonic organisms is determined by local abundance, which scales with body size, ultimately setting global spatial patterns of diversity.

  5. Host body size and the diversity of tick assemblages on Neotropical vertebrates

    Directory of Open Access Journals (Sweden)

    Helen J. Esser

    2016-12-01

    Full Text Available Identifying the factors that influence the species diversity and distribution of ticks (Acari: Ixodida across vertebrate host taxa is of fundamental ecological and medical importance. Host body size is considered one of the most important determinants of tick abundance, with larger hosts having higher tick burdens. The species diversity of tick assemblages should also be greater on larger-bodied host species, but empirical studies testing this hypothesis are lacking. Here, we evaluate this relationship using a comparative dataset of feeding associations from Panama between 45 tick species and 171 host species that range in body size by three orders of magnitude. We found that tick species diversity increased with host body size for adult ticks but not for immature ticks. We also found that closely related host species tended to have similar tick species diversity, but correcting for host phylogeny did not alter the relationships between host body size and tick species diversity. The distribution of tick species was highly aggregated, with approximately 20% of the host species harboring 80% of all tick species, following the Pareto principle or 20/80 Rule. Thus, the aggregated pattern commonly observed for tick burdens and disease transmission also holds for patterns of tick species richness. Our finding that the adult ticks in this system preferentially parasitize large-bodied host species suggests that the ongoing anthropogenic loss of large-bodied vertebrates is likely to result in host-tick coextinction events, even when immature stages feed opportunistically. As parasites play critical roles in ecological and evolutionary processes, such losses may profoundly affect ecosystem functioning and services.

  6. Body size, performance and fitness in galapagos marine iguanas.

    Science.gov (United States)

    Wikelski, Martin; Romero, L Michael

    2003-07-01

    Complex organismal traits such as body size are influenced by innumerable selective pressures, making the prediction of evolutionary trajectories for those traits difficult. A potentially powerful way to predict fitness in natural systems is to study the composite response of individuals in terms of performance measures, such as foraging or reproductive performance. Once key performance measures are identified in this top-down approach, we can determine the underlying physiological mechanisms and gain predictive power over long-term evolutionary processes. Here we use marine iguanas as a model system where body size differs by more than one order of magnitude between island populations. We identified foraging efficiency as the main performance measure that constrains body size. Mechanistically, foraging performance is determined by food pasture height and the thermal environment, influencing intake and digestion. Stress hormones may be a flexible way of influencing an individual's response to low-food situations that may be caused by high population density, famines, or anthropogenic disturbances like oil spills. Reproductive performance, on the other hand, increases with body size and is mediated by higher survival of larger hatchlings from larger females and increased mating success of larger males. Reproductive performance of males may be adjusted via plastic hormonal feedback mechanisms that allow individuals to assess their social rank annually within the current population size structure. When integrated, these data suggest that reproductive performance favors increased body size (influenced by reproductive hormones), with an overall limit imposed by foraging performance (influenced by stress hormones). Based on our mechanistic understanding of individual performances we predicted an evolutionary increase in maximum body size caused by global warming trends. We support this prediction using specimens collected during 1905. We also show in a common

  7. Visual attention mediates the relationship between body satisfaction and susceptibility to the body size adaptation effect.

    Science.gov (United States)

    Stephen, Ian D; Sturman, Daniel; Stevenson, Richard J; Mond, Jonathan; Brooks, Kevin R

    2018-01-01

    Body size misperception-the belief that one is larger or smaller than reality-affects a large and growing segment of the population. Recently, studies have shown that exposure to extreme body stimuli results in a shift in the point of subjective normality, suggesting that visual adaptation may be a mechanism by which body size misperception occurs. Yet, despite being exposed to a similar set of bodies, some individuals within a given geographical area will develop body size misperception and others will not. The reason for these individual difference is currently unknown. One possible explanation stems from the observation that women with lower levels of body satisfaction have been found to pay more attention to images of thin bodies. However, while attention has been shown to enhance visual adaptation effects in low (e.g. rotational and linear motion) and high level stimuli (e.g., facial gender), it is not known whether this effect exists in visual adaptation to body size. Here, we test the hypothesis that there is an indirect effect of body satisfaction on the direction and magnitude of the body fat adaptation effect, mediated via visual attention (i.e., selectively attending to images of thin over fat bodies or vice versa). Significant mediation effects were found in both men and women, suggesting that observers' level of body satisfaction may influence selective visual attention to thin or fat bodies, which in turn influences the magnitude and direction of visual adaptation to body size. This may provide a potential mechanism by which some individuals develop body size misperception-a risk factor for eating disorders, compulsive exercise behaviour and steroid abuse-while others do not.

  8. The evolution of body size and shape in the human career

    Science.gov (United States)

    Grabowski, Mark; Hatala, Kevin G.; Richmond, Brian G.

    2016-01-01

    Body size is a fundamental biological property of organisms, and documenting body size variation in hominin evolution is an important goal of palaeoanthropology. Estimating body mass appears deceptively simple but is laden with theoretical and pragmatic assumptions about best predictors and the most appropriate reference samples. Modern human training samples with known masses are arguably the ‘best’ for estimating size in early bipedal hominins such as the australopiths and all members of the genus Homo, but it is not clear if they are the most appropriate priors for reconstructing the size of the earliest putative hominins such as Orrorin and Ardipithecus. The trajectory of body size evolution in the early part of the human career is reviewed here and found to be complex and nonlinear. Australopith body size varies enormously across both space and time. The pre-erectus early Homo fossil record from Africa is poor and dominated by relatively small-bodied individuals, implying that the emergence of the genus Homo is probably not linked to an increase in body size or unprecedented increases in size variation. Body size differences alone cannot explain the observed variation in hominin body shape, especially when examined in the context of small fossil hominins and pygmy modern humans. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298459

  9. Taylor's law and body size in exploited marine ecosystems.

    Science.gov (United States)

    Cohen, Joel E; Plank, Michael J; Law, Richard

    2012-12-01

    Taylor's law (TL), which states that variance in population density is related to mean density via a power law, and density-mass allometry, which states that mean density is related to body mass via a power law, are two of the most widely observed patterns in ecology. Combining these two laws predicts that the variance in density is related to body mass via a power law (variance-mass allometry). Marine size spectra are known to exhibit density-mass allometry, but variance-mass allometry has not been investigated. We show that variance and body mass in unexploited size spectrum models are related by a power law, and that this leads to TL with an exponent slightly <2. These simulated relationships are disrupted less by balanced harvesting, in which fishing effort is spread across a wide range of body sizes, than by size-at-entry fishing, in which only fish above a certain size may legally be caught.

  10. Evidence for the Higher Importance of Signal Size Over Body Size in Aposematic Signaling in Insects

    OpenAIRE

    Remmel, Triinu; Tammarub, Toomas

    2011-01-01

    To understand the evolution of warning coloration, it is important to distinguish between different aspects of conspicuous color patterns. As an example, both pattern element size and body size of prey have been shown to enhance the effectiveness of warning signals. However, it is unclear whether the effect of body size is merely a side effect of proportionally increasing pattern elements, or if there is an effect of body size per se. These possibilities were evaluated by offering different s...

  11. Can blind persons accurately assess body size from the voice?

    Science.gov (United States)

    Pisanski, Katarzyna; Oleszkiewicz, Anna; Sorokowska, Agnieszka

    2016-04-01

    Vocal tract resonances provide reliable information about a speaker's body size that human listeners use for biosocial judgements as well as speech recognition. Although humans can accurately assess men's relative body size from the voice alone, how this ability is acquired remains unknown. In this study, we test the prediction that accurate voice-based size estimation is possible without prior audiovisual experience linking low frequencies to large bodies. Ninety-one healthy congenitally or early blind, late blind and sighted adults (aged 20-65) participated in the study. On the basis of vowel sounds alone, participants assessed the relative body sizes of male pairs of varying heights. Accuracy of voice-based body size assessments significantly exceeded chance and did not differ among participants who were sighted, or congenitally blind or who had lost their sight later in life. Accuracy increased significantly with relative differences in physical height between men, suggesting that both blind and sighted participants used reliable vocal cues to size (i.e. vocal tract resonances). Our findings demonstrate that prior visual experience is not necessary for accurate body size estimation. This capacity, integral to both nonverbal communication and speech perception, may be present at birth or may generalize from broader cross-modal correspondences. © 2016 The Author(s).

  12. Influence of body size on coexistence of bird species

    NARCIS (Netherlands)

    Leyequien Abarca, E.; Boer, de W.F.; Cleef, A.M.

    2007-01-01

    Theory suggests that body size is an important factor in determining interspecific competition and, ultimately, in structuring ecological communities. However, there is a lack of pragmatic studies linking body size and interspecific competition to patterns in ecological communities. The objective of

  13. Impact of ancestry and body size on sonographic ulnar nerve dimensions

    International Nuclear Information System (INIS)

    Childs, Jessie T.; Phillips, Maureen; Thoirs, Kerry A.

    2012-01-01

    Introduction: The purpose of this study was to investigate the impact that geographic ancestry and body size have on ultrasonographic measurements of the ulnar nerve size measured at the elbow. Materials and methods: We performed anthropometric measurements of body size and ultrasonographic measurements of the ulnar nerve at the elbow on 13 Vietnamese and 24 European participants. Regression analysis was used to determine the effect of body size and geographic ancestry on ulnar nerve size. Results: BMI had the greatest impact on ulnar nerve size. The short axis diameter was least resilient, and the long axis diameter was the most resilient to the effects of body size and geographic ancestry. Discussion: The long axis diameter has an apparent immunity to the influences of overall body size, arm size, or geographic ancestry and has the most potential as a sensitive discriminator between normal nerves and nerves affected by ulnar neuropathy at the elbow.

  14. Body size diversity and frequency distributions of Neotropical cichlid fishes (Cichliformes: Cichlidae: Cichlinae.

    Directory of Open Access Journals (Sweden)

    Sarah E Steele

    Full Text Available Body size is an important correlate of life history, ecology and distribution of species. Despite this, very little is known about body size evolution in fishes, particularly freshwater fishes of the Neotropics where species and body size diversity are relatively high. Phylogenetic history and body size data were used to explore body size frequency distributions in Neotropical cichlids, a broadly distributed and ecologically diverse group of fishes that is highly representative of body size diversity in Neotropical freshwater fishes. We test for divergence, phylogenetic autocorrelation and among-clade partitioning of body size space. Neotropical cichlids show low phylogenetic autocorrelation and divergence within and among taxonomic levels. Three distinct regions of body size space were identified from body size frequency distributions at various taxonomic levels corresponding to subclades of the most diverse tribe, Geophagini. These regions suggest that lineages may be evolving towards particular size optima that may be tied to specific ecological roles. The diversification of Geophagini appears to constrain the evolution of body size among other Neotropical cichlid lineages; non-Geophagini clades show lower species-richness in body size regions shared with Geophagini. Neotropical cichlid genera show less divergence and extreme body size than expected within and among tribes. Body size divergence among species may instead be present or linked to ecology at the community assembly scale.

  15. Dinosaurs, dragons, and dwarfs: The evolution of maximal body size

    Science.gov (United States)

    Burness, Gary P.; Diamond, Jared; Flannery, Timothy

    2001-01-01

    Among local faunas, the maximum body size and taxonomic affiliation of the top terrestrial vertebrate vary greatly. Does this variation reflect how food requirements differ between trophic levels (herbivores vs. carnivores) and with taxonomic affiliation (mammals and birds vs. reptiles)? We gathered data on the body size and food requirements of the top terrestrial herbivores and carnivores, over the past 65,000 years, from oceanic islands and continents. The body mass of the top species was found to increase with increasing land area, with a slope similar to that of the relation between body mass and home range area, suggesting that maximum body size is determined by the number of home ranges that can fit into a given land area. For a given land area, the body size of the top species decreased in the sequence: ectothermic herbivore > endothermic herbivore > ectothermic carnivore > endothermic carnivore. When we converted body mass to food requirements, the food consumption of a top herbivore was about 8 times that of a top carnivore, in accord with the factor expected from the trophic pyramid. Although top ectotherms were heavier than top endotherms at a given trophic level, lower metabolic rates per gram of body mass in ectotherms resulted in endotherms and ectotherms having the same food consumption. These patterns explain the size of the largest-ever extinct mammal, but the size of the largest dinosaurs exceeds that predicted from land areas and remains unexplained. PMID:11724953

  16. Emaciated mannequins: a study of mannequin body size in high street fashion stores.

    Science.gov (United States)

    Robinson, Eric; Aveyard, Paul

    2017-01-01

    There is concern that the body size of fashion store mannequins are too thin and promote unrealistic body ideals. To date there has been no systematic examination of the size of high street fashion store mannequins. We surveyed national fashion retailers located on the high street of two English cities. The body size of 'male' and 'female' mannequins was assessed by two blinded research assistants using visual rating scales. The average female mannequin body size was representative of a very underweight woman and 100% of female mannequins represented an underweight body size. The average male mannequin body size was significantly larger than the average female mannequin body size. Only 8% of male mannequins represented an underweight body size. The body size of mannequins used to advertise female fashion is unrealistic and would be considered medically unhealthy in humans.

  17. Perception of biological motion from size-invariant body representations

    Directory of Open Access Journals (Sweden)

    Markus eLappe

    2015-03-01

    Full Text Available The visual recognition of action is one of the socially most important and computationally demanding capacities of the human visual system. It combines visual shape recognition with complex non-rigid motion perception. Action presented as a point-light animation is a striking visual experience for anyone who sees it for the first time. Information about the shape and posture of the human body is sparse in point-light animations, but it is essential for action recognition. In the posturo-temporal filter model of biological motion perception posture information is picked up by visual neurons tuned to the form of the human body before body motion is calculated. We tested whether point-light stimuli are processed through posture recognition of the human body form by using a typical feature of form recognition, namely size invariance. We constructed a point-light stimulus that can only be perceived through a size-invariant mechanism. This stimulus changes rapidly in size from one image to the next. It thus disrupts continuity of early visuo-spatial properties but maintains continuity of the body posture representation. Despite this massive manipulation at the visuo-spatial level, size-changing point-light figures are spontaneously recognized by naive observers, and support discrimination of human body motion.

  18. Regulation of Caenorhabditis elegans body size and male tail development by the novel gene lon-8

    Directory of Open Access Journals (Sweden)

    Korswagen Hendrik C

    2007-03-01

    Full Text Available Abstract Background In C. elegans and other nematode species, body size is determined by the composition of the extracellular cuticle as well as by the nuclear DNA content of the underlying hypodermis. Mutants that are defective in these processes can exhibit either a short or a long body size phenotype. Several mutations that give a long body size (Lon phenotype have been characterized and found to be regulated by the DBL-1/TGF-β pathway, that controls post-embryonic growth and male tail development. Results Here we characterize a novel gene affecting body size. lon-8 encodes a secreted product of the hypodermis that is highly conserved in Rhabditid nematodes. lon-8 regulates larval elongation as well as male tail development. In both processes, lon-8 appears to function independently of the Sma/Mab pathway. Rather, lon-8 genetically interacts with dpy-11 and dpy-18, which encode cuticle collagen modifying enzymes. Conclusion The novel gene lon-8 encodes a secreted product of the hypodermis that controls body size and male ray morphology in C. elegans. lon-8 genetically interacts with enzymes that affect the composition of the cuticle.

  19. Expand Your Horizon: A programme that improves body image and reduces self-objectification by training women to focus on body functionality.

    Science.gov (United States)

    Alleva, Jessica M; Martijn, Carolien; Van Breukelen, Gerard J P; Jansen, Anita; Karos, Kai

    2015-09-01

    This study tested Expand Your Horizon, a programme designed to improve body image by training women to focus on the functionality of their body using structured writing assignments. Eighty-one women (Mage=22.77) with a negative body image were randomised to the Expand Your Horizon programme or to an active control programme. Appearance satisfaction, functionality satisfaction, body appreciation, and self-objectification were measured at pretest, posttest, and one-week follow-up. Following the intervention, participants in the Expand Your Horizon programme experienced greater appearance satisfaction, functionality satisfaction, and body appreciation, and lower levels of self-objectification, compared to participants in the control programme. Partial eta-squared effect sizes were of small to medium magnitude. This study is the first to show that focusing on body functionality can improve body image and reduce self-objectification in women with a negative body image. These findings provide support for addressing body functionality in programmes designed to improve body image. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Sexual Size Dimorphism and Body Condition in the Australasian Gannet.

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    Lauren P Angel

    Full Text Available Sexual size dimorphism is widespread throughout seabird taxa and several drivers leading to its evolution have been hypothesised. While the Australasian Gannet (Morus serrator has previously been considered nominally monomorphic, recent studies have documented sexual segregation in diet and foraging areas, traits often associated with size dimorphism. The present study investigated the sex differences in body mass and structural size of this species at two colonies (Pope's Eye, PE; Point Danger, PD in northern Bass Strait, south-eastern Australia. Females were found to be 3.1% and 7.3% heavier (2.74 ± 0.03, n = 92; 2.67 ± 0.03 kg, n = 43 than males (2.66 ± 0.03, n = 92; 2.48 ± 0.03 kg, n = 43 at PE and PD, respectively. Females were also larger in wing ulna length (0.8% both colonies but smaller in bill depth (PE: 2.2%; PD: 1.7% than males. Despite this dimorphism, a discriminant function provided only mild accuracy in determining sex. A similar degree of dimorphism was also found within breeding pairs, however assortative mating was not apparent at either colony (R2 < 0.04. Using hydrogen isotope dilution, a body condition index was developed from morphometrics to estimate total body fat (TBF stores, where TBF(% = 24.43+1.94*(body mass/wing ulna length - 0.58*tarsus length (r2 = 0.84, n = 15. This index was used to estimate body composition in all sampled individuals. There was no significant difference in TBF(% between the sexes for any stage of breeding or in any year of the study at either colony suggesting that, despite a greater body mass, females were not in a better condition than males. While the driving mechanism for sexual dimorphism in this species is currently unknown, studies of other Sulids indicate segregation in foraging behaviour, habitat and diet may be a contributing factor.

  1. Body size satisfaction and physical activity levels among men and women.

    Science.gov (United States)

    Kruger, Judy; Lee, Chong-Do; Ainsworth, Barbara E; Macera, Caroline A

    2008-08-01

    Body size satisfaction may be an important factor associated with physical activity. We analyzed data from the 2002 National Physical Activity and Weight Loss Survey (NPAWLS), a population-based cross-sectional telephone survey of US adults. Multiple logistic regression models were used to examine the association of body size satisfaction on being regularly active. Participants were aged > or =18 years with complete data on weight, race/ethnicity, physical activity level, and body size satisfaction (n = 10,021). More than half of men (55.8%) and women (53.3%) who reported being very satisfied with the body size were regularly active. After adjustment for covariates, participants who reported being somewhat or not satisfied with their body size had a 13 and 44% lower odds of being regularly active, respectively, compared with those very satisfied with their body size. When stratified by race/ethnicity, this association remained in whites (P for trend physical activity than those less satisfied. Further research is needed to explore predictors of physical activity to reduce health disparities.

  2. Macroscale patterns in body size of intertidal crustaceans provide insights on climate change effects

    Science.gov (United States)

    Dugan, Jenifer E.; Hubbard, David M.; Contreras, Heraldo; Duarte, Cristian; Acuña, Emilio; Schoeman, David S.

    2017-01-01

    Predicting responses of coastal ecosystems to altered sea surface temperatures (SST) associated with global climate change, requires knowledge of demographic responses of individual species. Body size is an excellent metric because it scales strongly with growth and fecundity for many ectotherms. These attributes can underpin demographic as well as community and ecosystem level processes, providing valuable insights for responses of vulnerable coastal ecosystems to changing climate. We investigated contemporary macroscale patterns in body size among widely distributed crustaceans that comprise the majority of intertidal abundance and biomass of sandy beach ecosystems of the eastern Pacific coasts of Chile and California, USA. We focused on ecologically important species representing different tidal zones, trophic guilds and developmental modes, including a high-shore macroalga-consuming talitrid amphipod (Orchestoidea tuberculata), two mid-shore scavenging cirolanid isopods (Excirolana braziliensis and E. hirsuticauda), and a low-shore suspension-feeding hippid crab (Emerita analoga) with an amphitropical distribution. Significant latitudinal patterns in body sizes were observed for all species in Chile (21° - 42°S), with similar but steeper patterns in Emerita analoga, in California (32°- 41°N). Sea surface temperature was a strong predictor of body size (-4% to -35% °C-1) in all species. Beach characteristics were subsidiary predictors of body size. Alterations in ocean temperatures of even a few degrees associated with global climate change are likely to affect body sizes of important intertidal ectotherms, with consequences for population demography, life history, community structure, trophic interactions, food-webs, and indirect effects such as ecosystem function. The consistency of results for body size and temperature across species with different life histories, feeding modes, ecological roles, and microhabitats inhabiting a single widespread coastal

  3. Correlates of self-worth and body size dissatisfaction among obese Latino youth.

    Science.gov (United States)

    Mirza, Nazrat M; Mackey, Eleanor Race; Armstrong, Bridget; Jaramillo, Ana; Palmer, Matilde M

    2011-03-01

    The current study examined self-worth and body size dissatisfaction, and their association with maternal acculturation among obese Latino youth enrolled in a community-based obesity intervention program. Upon entry to the program, a sample of 113 participants reported global self-worth comparable to general population norms, but lower athletic competence and perception of physical appearance. Interestingly, body size dissatisfaction was more prevalent among younger respondents. Youth body size dissatisfaction was associated with less acculturated mothers and higher maternal dissatisfaction with their child's body size. By contrast, although global self-worth was significantly related to body dissatisfaction, it was not influenced by mothers' acculturation or dissatisfaction with their own or their child's body size. Obesity intervention programs targeted to Latino youth need to address self-worth concerns among the youth as well as addressing maternal dissatisfaction with their children's body size. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Human vocal attractiveness as signaled by body size projection.

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    Yi Xu

    Full Text Available Voice, as a secondary sexual characteristic, is known to affect the perceived attractiveness of human individuals. But the underlying mechanism of vocal attractiveness has remained unclear. Here, we presented human listeners with acoustically altered natural sentences and fully synthetic sentences with systematically manipulated pitch, formants and voice quality based on a principle of body size projection reported for animal calls and emotional human vocal expressions. The results show that male listeners preferred a female voice that signals a small body size, with relatively high pitch, wide formant dispersion and breathy voice, while female listeners preferred a male voice that signals a large body size with low pitch and narrow formant dispersion. Interestingly, however, male vocal attractiveness was also enhanced by breathiness, which presumably softened the aggressiveness associated with a large body size. These results, together with the additional finding that the same vocal dimensions also affect emotion judgment, indicate that humans still employ a vocal interaction strategy used in animal calls despite the development of complex language.

  5. Body-size spectra of biofilm-dwelling protozoa and their seasonal shift in coastal ecosystems.

    Science.gov (United States)

    Zhao, Lu; Xu, Guangjian; Wang, Zheng; Xu, Henglong

    2016-10-01

    Community-based assessment of protozoa is usually performed at a taxon-dependent resolution. As an inherent 'taxon-free' trait, however, body-size spectrum has proved to be a highly informative indicator to summarize the functional structure of a community in both community research and monitoring programs in aquatic ecosystems. To demonstrate the relationships between the taxon-free resolution of protozoan communities and water conditions, the body-size spectra of biofilm-dwelling protozoa and their seasonal shift and environmental drivers were explored based on an annual dataset collected monthly from coastal waters of the Yellow Sea, northern China. Body sizes were calculated in equivalent spherical diameter (ESD). Among a total of 8 body-size ranks, S2 (19-27μm), S3 (28-36μm), S4 (37-50μm) and S5 (53-71μm) were the top four levels in frequency of occurrence, while rank S1 (13-17μm), S2 and S4 were the dominant levels in abundance. These dominants showed a clear seasonal succession: S2/S4 (spring)→S2/S4 (summer)→S4 (autumn)→S2 (winter) in frequency of occurrence; S1 (spring)→S4 (summer)→S2 (autumn)→S1 (winter) in abundance. Bootstrapped average analysis showed a clear seasonal shift in body-size spectra of the protozoa during a 1-year cycle, and the best-matching analysis demonstrated that the temporal variations in frequency of occurrence and abundance were significantly correlated with water temperature, pH, dissolved oxygen (DO), alone or in combination with chemical oxygen demand (COD) and nutrients. Thus, the body-size spectra of biofilm-dwelling protozoa were seasonally shaped and might be used as a time and cost efficient bioindicator of water quality in marine ecosystems. Copyright © 2016 Elsevier GmbH. All rights reserved.

  6. Evolution of extreme body size disparity in monitor lizards (Varanus).

    Science.gov (United States)

    Collar, David C; Schulte, James A; Losos, Jonathan B

    2011-09-01

    Many features of species' biology, including life history, physiology, morphology, and ecology are tightly linked to body size. Investigation into the causes of size divergence is therefore critical to understanding the factors shaping phenotypic diversity within clades. In this study, we examined size evolution in monitor lizards (Varanus), a clade that includes the largest extant lizard species, the Komodo dragon (V. komodoensis), as well as diminutive species that are nearly four orders of magnitude smaller in adult body mass. We demonstrate that the remarkable body size disparity of this clade is a consequence of different selective demands imposed by three major habitat use patterns-arboreality, terrestriality, and rock-dwelling. We reconstructed phylogenetic relationships and ancestral habitat use and applied model selection to determine that the best-fitting evolutionary models for species' adult size are those that infer oppositely directed adaptive evolution associated with terrestriality and rock-dwelling, with terrestrial lineages evolving extremely large size and rock-dwellers becoming very small. We also show that habitat use affects the evolution of several ecologically important morphological traits independently of body size divergence. These results suggest that habitat use exerts a strong, multidimensional influence on the evolution of morphological size and shape disparity in monitor lizards. © 2011 The Author(s).

  7. Body size distributions signal a regime shift in a lake ...

    Science.gov (United States)

    Communities of organisms, from mammals to microorganisms, have discontinuous distributions of body size. This pattern of size structuring is a conservative trait of community organization and is a product of processes that occur at multiple spatial and temporal scales. In this study, we assessed whether body size patterns serve as an indicator of a threshold between alternative regimes. Over the past 7000 years, the biological communities of Foy Lake (Montana,USA) have undergone a major regime shift owing to climate change. We used a palaeoecological record of diatom communities to estimate diatom sizes, and then analysed the discontinuous distribution of organism sizes over time. We used Bayesian classification and regression tree models to determine that all time intervals exhibited aggregations of sizes separated by gaps in the distribution and found a significant change in diatom body size distributions approximately 150 years before the identified ecosystem regime shift. We suggest that discontinuity analysis is a useful addition to the suite of tools for the detection of early warning signals of regime shifts. Communities of organisms from mammals to microorganisms have discontinuous distributions of body size. This pattern of size structuring is a conservative trait of community organization and is a product of processes that occur at discrete spatial and temporal scales within ecosystems. Here, a paleoecological record of diatom community change is use

  8. The influence of personal BMI on body size estimations and sensitivity to body size change in anorexia spectrum disorders.

    OpenAIRE

    Cornelissen, Katri; Bester, Andre; Cairns, Paul; Tovee, Martin; Cornelissen, Piers

    2015-01-01

    In this cross-sectional study, we investigated the influence of personal BMI on body size estimation in 42 women who have symptoms of anorexia (referred to henceforth as anorexia spectrum disorders, ANSD), and 100 healthy controls. Low BMI control participants over-estimate their size and high BMI controls under-estimate, a pattern which is predicted by a perceptual phenomenon called contraction bias. In addition, control participants' sensitivity to size change declines as their BMI increase...

  9. Variability in human body size

    Science.gov (United States)

    Annis, J. F.

    1978-01-01

    The range of variability found among homogeneous groups is described and illustrated. Those trends that show significantly marked differences between sexes and among a number of racial/ethnic groups are also presented. Causes of human-body size variability discussed include genetic endowment, aging, nutrition, protective garments, and occupation. The information is presented to aid design engineers of space flight hardware and equipment.

  10. Effect of body size and body mass on δ 13 C and δ 15 N in coastal fishes and cephalopods

    Science.gov (United States)

    Vinagre, C.; Máguas, C.; Cabral, H. N.; Costa, M. J.

    2011-11-01

    Carbon and nitrogen isotopes have been widely used in the investigation of trophic relations, energy pathways, trophic levels and migrations, under the assumption that δ 13C is independent of body size and that variation in δ 15N occurs exclusively due to ontogenetic changes in diet and not body size increase per se. However, several studies have shown that these assumptions are uncertain. Data from food-webs containing an important number of species lack theoretical support on these assumptions because very few species have been tested for δ 13C and δ 15N variation in captivity. However, if sampling comprises a wide range of body sizes from various species, the variation of δ 13C and δ 15N with body size can be investigated. While correlation between body size and δ 13C and δ 15N can be due to ontogenetic diet shifts, stability in such values throughout the size spectrum can be considered an indication that δ 13C and δ 15N in muscle tissues of such species is independent of body size within that size range, and thus the basic assumptions can be applied in the interpretation of such food webs. The present study investigated the variation in muscle δ 13C and δ 15N with body size and body mass of coastal fishes and cephalopods. It was concluded that muscle δ 13C and δ 15N did not vary with body size or mass for all bony fishes with only one exception, the dragonet Callionymus lyra. Muscle δ 13C and δ 15N also did not vary with body size or mass in cartilaginous fishes and cephalopods, meaning that body size/mass per se have no effect on δ 13C or δ 15N, for most species analysed and within the size ranges sampled. The assumption that δ 13C is independent of body size and that variation in δ 15N is not affected by body size increase per se was upheld for most organisms and can be applied to the coastal food web studied taking into account that C. lyra is an exception.

  11. crm-1 facilitates BMP signaling to control body size in Caenorhabditis elegans.

    Science.gov (United States)

    Fung, Wong Yan; Fat, Ko Frankie Chi; Eng, Cheah Kathryn Song; Lau, Chow King

    2007-11-01

    We have identified in Caenorhabditis elegans a homologue of the vertebrate Crim1, crm-1, which encodes a putative transmembrane protein with multiple cysteine-rich (CR) domains known to have bone morphogenetic proteins (BMPs) binding activity. Using the body morphology of C. elegans as an indicator, we showed that attenuation of crm-1 activity leads to a small body phenotype reminiscent of that of BMP pathway mutants. We showed that the crm-1 loss-of-function phenotype can be rescued by constitutive supply of sma-4 activity. crm-1 can enhance BMP signaling and this activity is dependent on the presence of the DBL-1 ligand and its receptors. crm-1 is expressed in neurons at the ventral nerve cord, where the DBL-1 ligand is produced. However, ectopic expression experiments reveal that crm-1 gene products act outside the DBL-1 producing cells and function non-autonomously to facilitate dbl/sma pathway signaling to control body size.

  12. Increased body size along urbanization gradients at both community and intraspecific level in macro-moths.

    Science.gov (United States)

    Merckx, Thomas; Kaiser, Aurélien; Van Dyck, Hans

    2018-05-23

    Urbanization involves a cocktail of human-induced rapid environmental changes and is forecasted to gain further importance. Urban-heat-island effects result in increased metabolic costs expected to drive shifts towards smaller body sizes. However, urban environments are also characterized by strong habitat fragmentation, often selecting for dispersal phenotypes. Here, we investigate to what extent, and at which spatial scale(s), urbanization drives body size shifts in macro-moths-an insect group characterized by positive size-dispersal links-at both the community and intraspecific level. Using light and bait trapping as part of a replicated, spatially nested sampling design, we show that despite the observed urban warming of their woodland habitat, macro-moth communities display considerable increases in community-weighted mean body size because of stronger filtering against small species along urbanization gradients. Urbanization drives intraspecific shifts towards increased body size too, at least for a third of species analysed. These results indicate that urbanization drives shifts towards larger, and hence, more mobile species and individuals in order to mitigate low connectivity of ecological resources in urban settings. Macro-moths are a key group within terrestrial ecosystems, and since body size is central to species interactions, such urbanization-driven phenotypic change may impact urban ecosystem functioning, especially in terms of nocturnal pollination and food web dynamics. Although we show that urbanization's size-biased filtering happens simultaneously and coherently at both the inter- and intraspecific level, we demonstrate that the impact at the community level is most pronounced at the 800 m radius scale, whereas species-specific size increases happen at local and landscape scales (50-3,200 m radius), depending on the species. Hence, measures-such as creating and improving urban green infrastructure-to mitigate the effects of urbanization on

  13. Population-based resequencing of experimentally evolved populations reveals the genetic basis of body size variation in Drosophila melanogaster.

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    Thomas L Turner

    2011-03-01

    Full Text Available Body size is a classic quantitative trait with evolutionarily significant variation within many species. Locating the alleles responsible for this variation would help understand the maintenance of variation in body size in particular, as well as quantitative traits in general. However, successful genome-wide association of genotype and phenotype may require very large sample sizes if alleles have low population frequencies or modest effects. As a complementary approach, we propose that population-based resequencing of experimentally evolved populations allows for considerable power to map functional variation. Here, we use this technique to investigate the genetic basis of natural variation in body size in Drosophila melanogaster. Significant differentiation of hundreds of loci in replicate selection populations supports the hypothesis that the genetic basis of body size variation is very polygenic in D. melanogaster. Significantly differentiated variants are limited to single genes at some loci, allowing precise hypotheses to be formed regarding causal polymorphisms, while other significant regions are large and contain many genes. By using significantly associated polymorphisms as a priori candidates in follow-up studies, these data are expected to provide considerable power to determine the genetic basis of natural variation in body size.

  14. Oxygen no longer plays a major role in Body Size Evolution

    Science.gov (United States)

    Datta, H.; Sachson, W.; Heim, N. A.; Payne, J.

    2015-12-01

    When observing the long-term relationship between atmospheric oxygen and the maximum size in organisms across the Geozoic (~3.8 Ga - present), it appears that as oxygen increases, organism size grows. However, during the Phanerozoic (541 Ma - Present) oxygen levels varied, so we set out to test the hypothesis that oxygen levels drive patterns marine animal body size evolution. Expected decreases in maximum size due to a lack of oxygen do not occur, and instead, body size continues to increase regardless. In the oxygen data, a relatively low atmospheric oxygen percentage can support increasing body size, so our research tries to determine whether lifestyle affects body size in marine organisms. The genera in the data set were organized based on their tiering, motility, and feeding, such as a pelagic, fully-motile, predator. When organisms fill a certain ecological niche to take advantage of resources, they will have certain life modes, rather than randomly selected traits. For example, even in terrestrial environments, large animals have to constantly feed themselves to support their expensive terrestrial lifestyle which involves fairly consistent movement, and the structural support necessary for that movement. Only organisms with access to high energy food sources or large amounts of food can support themselves, and that is before they expend energy elsewhere. Organisms that expend energy frugally when active or have slower metabolisms in comparison to body size have a more efficient lifestyle and are generally able to grow larger, while those who have higher energy demands like predators are limited to comparatively smaller sizes. Therefore, in respect to the fossil record and modern measurements of animals, the metabolism and lifestyle of an organism dictate its body size in general. With this further clarification on the patterns of evolution, it will be easier to observe and understand the reasons for the ecological traits of organisms today.

  15. Deforestation and stream warming affect body size of Amazonian fishes.

    Science.gov (United States)

    Ilha, Paulo; Schiesari, Luis; Yanagawa, Fernando I; Jankowski, KathiJo; Navas, Carlos A

    2018-01-01

    Declining body size has been suggested to be a universal response of organisms to rising temperatures, manifesting at all levels of organization and in a broad range of taxa. However, no study to date evaluated whether deforestation-driven warming could trigger a similar response. We studied changes in fish body size, from individuals to assemblages, in streams in Southeastern Amazonia. We first conducted sampling surveys to validate the assumption that deforestation promoted stream warming, and to test the hypothesis that warmer deforested streams had reduced fish body sizes relative to cooler forest streams. As predicted, deforested streams were up to 6 °C warmer and had fish 36% smaller than forest streams on average. This body size reduction could be largely explained by the responses of the four most common species, which were 43-55% smaller in deforested streams. We then conducted a laboratory experiment to test the hypothesis that stream warming as measured in the field was sufficient to cause a growth reduction in the dominant fish species in the region. Fish reared at forest stream temperatures gained mass, whereas those reared at deforested stream temperatures lost mass. Our results suggest that deforestation-driven stream warming is likely to be a relevant factor promoting observed body size reductions, although other changes in stream conditions, like reductions in organic matter inputs, can also be important. A broad scale reduction in fish body size due to warming may be occurring in streams throughout the Amazonian Arc of Deforestation, with potential implications for the conservation of Amazonian fish biodiversity and food supply for people around the Basin.

  16. Deforestation and stream warming affect body size of Amazonian fishes

    Science.gov (United States)

    Yanagawa, Fernando I.; Jankowski, KathiJo; Navas, Carlos A.

    2018-01-01

    Declining body size has been suggested to be a universal response of organisms to rising temperatures, manifesting at all levels of organization and in a broad range of taxa. However, no study to date evaluated whether deforestation-driven warming could trigger a similar response. We studied changes in fish body size, from individuals to assemblages, in streams in Southeastern Amazonia. We first conducted sampling surveys to validate the assumption that deforestation promoted stream warming, and to test the hypothesis that warmer deforested streams had reduced fish body sizes relative to cooler forest streams. As predicted, deforested streams were up to 6 °C warmer and had fish 36% smaller than forest streams on average. This body size reduction could be largely explained by the responses of the four most common species, which were 43–55% smaller in deforested streams. We then conducted a laboratory experiment to test the hypothesis that stream warming as measured in the field was sufficient to cause a growth reduction in the dominant fish species in the region. Fish reared at forest stream temperatures gained mass, whereas those reared at deforested stream temperatures lost mass. Our results suggest that deforestation-driven stream warming is likely to be a relevant factor promoting observed body size reductions, although other changes in stream conditions, like reductions in organic matter inputs, can also be important. A broad scale reduction in fish body size due to warming may be occurring in streams throughout the Amazonian Arc of Deforestation, with potential implications for the conservation of Amazonian fish biodiversity and food supply for people around the Basin. PMID:29718960

  17. No Effect of Featural Attention on Body Size Aftereffects

    Directory of Open Access Journals (Sweden)

    Ian David Stephen

    2016-08-01

    Full Text Available Prolonged exposure to images of narrow bodies has been shown to induce a perceptual aftereffect, such that observers’ point of subjective normality (PSN for bodies shifts towards narrower bodies. The converse effect is shown for adaptation to wide bodies. In low-level stimuli, object attention (attention directed to the object and spatial attention (attention directed to the location of the object have been shown to increase the magnitude of visual aftereffects, while object-based attention enhances the adaptation effect in faces. It is not known whether featural attention (attention directed to a specific aspect of the object affects the magnitude of adaptation effects in body stimuli. Here, we manipulate the attention of Caucasian observers to different featural information in body images, by asking them to rate the fatness or sex typicality of male and female bodies manipulated to appear fatter or thinner than average. PSNs for body fatness were taken at baseline and after adaptation, and a change in PSN (ΔPSN was calculated. A body size adaptation effect was found, with observers who viewed fat bodies showing an increased PSN, and those exposed to thin bodies showing a reduced PSN. However, manipulations of featural attention to body fatness or sex typicality produced equivalent results, suggesting that featural attention may not affect the strength of the body size aftereffect.

  18. No Effect of Featural Attention on Body Size Aftereffects.

    Science.gov (United States)

    Stephen, Ian D; Bickersteth, Chloe; Mond, Jonathan; Stevenson, Richard J; Brooks, Kevin R

    2016-01-01

    Prolonged exposure to images of narrow bodies has been shown to induce a perceptual aftereffect, such that observers' point of subjective normality (PSN) for bodies shifts toward narrower bodies. The converse effect is shown for adaptation to wide bodies. In low-level stimuli, object attention (attention directed to the object) and spatial attention (attention directed to the location of the object) have been shown to increase the magnitude of visual aftereffects, while object-based attention enhances the adaptation effect in faces. It is not known whether featural attention (attention directed to a specific aspect of the object) affects the magnitude of adaptation effects in body stimuli. Here, we manipulate the attention of Caucasian observers to different featural information in body images, by asking them to rate the fatness or sex typicality of male and female bodies manipulated to appear fatter or thinner than average. PSNs for body fatness were taken at baseline and after adaptation, and a change in PSN (ΔPSN) was calculated. A body size adaptation effect was found, with observers who viewed fat bodies showing an increased PSN, and those exposed to thin bodies showing a reduced PSN. However, manipulations of featural attention to body fatness or sex typicality produced equivalent results, suggesting that featural attention may not affect the strength of the body size aftereffect.

  19. Endothelial function in male body builders taking anabolic androgenic steroids

    Directory of Open Access Journals (Sweden)

    H Hashemi

    2005-11-01

    Full Text Available Background: Adverse cardiovascular events have been reported in body builders taking anabolic steroids. Adverse effects of AAS on endothelial function can initiate atherosclerosis. This study evaluates endothelial function in body builders using AAS, compared with non-steroids using athletes as controls. Methods: We recruited 30 nonsmoking male body builders taking AAS, 14 in build up phase, 8 in work out phase, and 8 in post steroid phase, and 30 nonsmoking male athletes who denied ever using steroids. Serum lipids and fasting plasma glucose were measured to exclude dyslipidemia and diabetes. Brachial artery diameter was measured by ultrasound at rest, after cuff inflation, and after sublingual glyceriltrinitrate (GTN to determine flow mediated dilation (FMD, nitro mediated dilation (NMD and ratio of FMD to NMD (index of endothelial function. Result: Use of AAS was associated with higher body mass index (BMI and low density lipoprotein–cholesterol (LDL-C. Mean ratio of flow mediated dilatation after cuff deflation to post GTN dilatation of brachial artery (index of endothelial function in body builders taking AAS was significantly lower than control group (0.96(0.05 versus 1(0.08; p=0.03. After adjusting BMI, age and weight, no significant difference was seen in index of endothelial function between two groups (p=0 .21. Conclusion: Our study indicates that taking AAS in body builders doesn’t have direct effect on endothelial function. Future study with bigger sample size and measurement of AAS metabolites is recommended. Key words: endothelium, lipids, anabolic steroids, body builders

  20. The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size.

    Science.gov (United States)

    Rideout, Elizabeth J; Narsaiya, Marcus S; Grewal, Savraj S

    2015-12-01

    Almost all animals show sex differences in body size. For example, in Drosophila, females are larger than males. Although Drosophila is widely used as a model to study growth, the mechanisms underlying this male-female difference in size remain unclear. Here, we describe a novel role for the sex determination gene transformer (tra) in promoting female body growth. Normally, Tra is expressed only in females. We find that loss of Tra in female larvae decreases body size, while ectopic Tra expression in males increases body size. Although we find that Tra exerts autonomous effects on cell size, we also discovered that Tra expression in the fat body augments female body size in a non cell-autonomous manner. These effects of Tra do not require its only known targets doublesex and fruitless. Instead, Tra expression in the female fat body promotes growth by stimulating the secretion of insulin-like peptides from insulin producing cells in the brain. Our data suggest a model of sex-specific growth in which body size is regulated by a previously unrecognized branch of the sex determination pathway, and identify Tra as a novel link between sex and the conserved insulin signaling pathway.

  1. The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size.

    Directory of Open Access Journals (Sweden)

    Elizabeth J Rideout

    2015-12-01

    Full Text Available Almost all animals show sex differences in body size. For example, in Drosophila, females are larger than males. Although Drosophila is widely used as a model to study growth, the mechanisms underlying this male-female difference in size remain unclear. Here, we describe a novel role for the sex determination gene transformer (tra in promoting female body growth. Normally, Tra is expressed only in females. We find that loss of Tra in female larvae decreases body size, while ectopic Tra expression in males increases body size. Although we find that Tra exerts autonomous effects on cell size, we also discovered that Tra expression in the fat body augments female body size in a non cell-autonomous manner. These effects of Tra do not require its only known targets doublesex and fruitless. Instead, Tra expression in the female fat body promotes growth by stimulating the secretion of insulin-like peptides from insulin producing cells in the brain. Our data suggest a model of sex-specific growth in which body size is regulated by a previously unrecognized branch of the sex determination pathway, and identify Tra as a novel link between sex and the conserved insulin signaling pathway.

  2. Stereometrical analysis of number and size of prolamellar bodies during pea chloroplast development

    Directory of Open Access Journals (Sweden)

    Agnieszka Mostowska

    2014-01-01

    Full Text Available The plastid prolamelar bodies in dark-grown pea seedlings undergo gradual transformation and decay after illumination with low intensity light. Random micrographs do not give direct information concerning the sizes and average numbers of prolamellar bodies in a plastid. These values were obtained after evaluation by a stereometrical method from the ratio of polamellar bodies sizes to the plastid size and from the frequency of prolamellar body sections of a given diameter. Plastids of dark-grown seedlings contained on the average at least one prolamellar body. After illumination the size of the bodies decreased rapidly owing to dispersion into primary thylakoids and split into much smaller numerous prolamellar bodies.

  3. Body Size Predicts Cardiac and Vascular Resistance Effects on Men's and Women's Blood Pressure

    Directory of Open Access Journals (Sweden)

    Joyce M. Evans

    2017-08-01

    Full Text Available Key Points SummaryWe report how blood pressure, cardiac output and vascular resistance are related to height, weight, body surface area (BSA, and body mass index (BMI in healthy young adults at supine rest and standing.Much inter-subject variability in young adult's blood pressure, currently attributed to health status, may actually result from inter-individual body size differences.Each cardiovascular variable is linearly related to height, weight and/or BSA (more than to BMI.When supine, cardiac output is positively related, while vascular resistance is negatively related, to body size. Upon standing, the change in vascular resistance is positively related to size.The height/weight relationships of cardiac output and vascular resistance to body size are responsible for blood pressure relationships to body size.These basic components of blood pressure could help distinguish normal from abnormal blood pressures in young adults by providing a more effective scaling mechanism.Introduction: Effects of body size on inter-subject blood pressure (BP variability are not well established in adults. We hypothesized that relationships linking stroke volume (SV, cardiac output (CO, and total peripheral resistance (TPR with body size would account for a significant fraction of inter-subject BP variability.Methods: Thirty-four young, healthy adults (19 men, 15 women participated in 38 stand tests during which brachial artery BP, heart rate, SV, CO, TPR, and indexes of body size were measured/calculated.Results: Steady state diastolic arterial BP was not significantly correlated with any index of body size when subjects were supine. However, upon standing, the more the subject weighed, or the taller s/he was, the greater the increase in diastolic pressure. Systolic pressure strongly correlated with body weight and height both supine and standing. Diastolic and systolic BP were more strongly related to height, weight and body surface area than to body mass

  4. Investigating body function

    International Nuclear Information System (INIS)

    Monks, R.; Riley, A.L.M.

    1981-01-01

    This invention relates to the investigation of body function, especially small bowel function but also liver function, using bile acids and bile salts or their metabolic precursors labelled with radio isotopes and selenium or tellurium. (author)

  5. Four-body wave function of π3He-system at the threshold energy

    International Nuclear Information System (INIS)

    Pupyshev, V.V.; Rakityanskij, S.A.

    1985-01-01

    On the basis of approximate four-body equations the wave function of π 3 He-system is calculated at zero kinetic energy of the pion. In the case when distances between all four particles are comparable with the nucleus size a strong distortion of the wave function of (3N)-subsystem caused by the presence of the pion is found. The calculated four-body function is represented in a semianalytical form, which makes it possible to apply it in different calculations

  6. Individual and species-specific traits explain niche size and functional role in spiders as generalist predators.

    Science.gov (United States)

    Sanders, Dirk; Vogel, Esther; Knop, Eva

    2015-01-01

    The function of a predator within a community is greatly based on its trophic niche, that is the number and the strength of feeding links. In generalist predators, which feed on a wide range of prey, the size and position of the trophic niche is likely determined by traits such as hunting mode, the stratum they occur in, their body size and age. We used stable isotope analyses ((13)C and (15)N) to measure the trophic niche size of nine spider species within a forest hedge community and tested for species traits and individual traits that influence stable isotope enrichment, niche size and resource use. The spiders Enoplognatha, Philodromus, Floronia, and Heliophanus had large isotopic niches, which correspond to a more generalistic feeding behaviour. In contrast, Araneus, Metellina and Agelena, as top predators in the system, had rather narrow niches. We found a negative correlation between trophic position and niche size. Differences in trophic position in spiders were explained by body size, hunting modes and stratum, while niche size was influenced by hunting mode. In Philodromus, the size of the trophic niche increased significantly with age. Fitting spiders to functional groups according to their mean body size, hunting mode and their habitat domain resulted in largely separated niches, which indicates that these traits are meaningful for separating functional entities in spiders. Functional groups based on habitat domain (stratum) caught the essential functional differences between the species with species higher up in the vegetation feeding on flying insects and herb and ground species also preying on forest floor decomposers. Interestingly, we found a gradient from large species using a higher habitat domain and having a smaller niche to smaller species foraging closer to the ground and having a larger niche. This shows that even within generalist predators, such as spiders, there is a gradient of specialism that can be predicted by functional traits.

  7. Body size mediated coexistence in swans.

    Science.gov (United States)

    Engelhardt, Katharina A M; Ritchie, Mark E; Powell, James A

    2014-01-01

    Differences in body sizes may create a trade-off between foraging efficiency (foraging gains/costs) and access to resources. Such a trade-off provides a potential mechanism for ecologically similar species to coexist on one resource. We explored this hypothesis for tundra (Cygnus columbianus) and trumpeter swans (Cygnus buccinator), a federally protected species, feeding solely on sago pondweed (Stuckenia pectinata) tubers during fall staging and wintering in northern Utah. Foraging efficiency was higher for tundra swans because this species experienced lower foraging and metabolic costs relative to foraging gains; however, trumpeter swans (a) had longer necks and therefore had access to exclusive resources buried deep in wetland sediments and (b) were more aggressive and could therefore displace tundra swans from lucrative foraging locations. We conclude that body size differentiation is an important feature of coexistence among ecologically similar species feeding on one resource. In situations where resources are limiting and competition for resources is strong, conservation managers will need to consider the trade-off between foraging efficiency and access to resources to ensure ecologically similar species can coexist on a shared resource.

  8. Body size mediated coexistence of consumers competing for resources in space

    Science.gov (United States)

    Basset, A.; Angelis, D.L.

    2007-01-01

    Body size is a major phenotypic trait of individuals that commonly differentiates co-occurring species. We analyzed inter-specific competitive interactions between a large consumer and smaller competitors, whose energetics, selection and giving-up behaviour on identical resource patches scaled with individual body size. The aim was to investigate whether pure metabolic constraints on patch behaviour of vagile species can determine coexistence conditions consistent with existing theoretical and experimental evidence. We used an individual-based spatially explicit simulation model at a spatial scale defined by the home range of the large consumer, which was assumed to be parthenogenic and semelparous. Under exploitative conditions, competitive coexistence occurred in a range of body size ratios between 2 and 10. Asymmetrical competition and the mechanism underlying asymmetry, determined by the scaling of energetics and patch behaviour with consumer body size, were the proximate determinant of inter-specific coexistence. The small consumer exploited patches more efficiently, but searched for profitable patches less effectively than the larger competitor. Therefore, body-size related constraints induced niche partitioning, allowing competitive coexistence within a set of conditions where the large consumer maintained control over the small consumer and resource dynamics. The model summarises and extends the existing evidence of species coexistence on a limiting resource, and provides a mechanistic explanation for decoding the size-abundance distribution patterns commonly observed at guild and community levels. ?? Oikos.

  9. Concerted evolution of body mass and cell size: similar patterns among species of birds (Galliformes) and mammals (Rodentia)

    Science.gov (United States)

    Dragosz-Kluska, Dominika; Pis, Tomasz; Pawlik, Katarzyna; Kapustka, Filip; Kilarski, Wincenty M.; Kozłowski, Jan

    2018-01-01

    ABSTRACT Cell size plays a role in body size evolution and environmental adaptations. Addressing these roles, we studied body mass and cell size in Galliformes birds and Rodentia mammals, and collected published data on their genome sizes. In birds, we measured erythrocyte nuclei and basal metabolic rates (BMRs). In birds and mammals, larger species consistently evolved larger cells for five cell types (erythrocytes, enterocytes, chondrocytes, skin epithelial cells, and kidney proximal tubule cells) and evolved smaller hepatocytes. We found no evidence that cell size differences originated through genome size changes. We conclude that the organism-wide coordination of cell size changes might be an evolutionarily conservative characteristic, and the convergent evolutionary body size and cell size changes in Galliformes and Rodentia suggest the adaptive significance of cell size. Recent theory predicts that species evolving larger cells waste less energy on tissue maintenance but have reduced capacities to deliver oxygen to mitochondria and metabolize resources. Indeed, birds with larger size of the abovementioned cell types and smaller hepatocytes have evolved lower mass-specific BMRs. We propose that the inconsistent pattern in hepatocytes derives from the efficient delivery system to hepatocytes, combined with their intense involvement in supracellular function and anabolic activity. PMID:29540429

  10. Concerted evolution of body mass and cell size: similar patterns among species of birds (Galliformes and mammals (Rodentia

    Directory of Open Access Journals (Sweden)

    Marcin Czarnoleski

    2018-04-01

    Full Text Available Cell size plays a role in body size evolution and environmental adaptations. Addressing these roles, we studied body mass and cell size in Galliformes birds and Rodentia mammals, and collected published data on their genome sizes. In birds, we measured erythrocyte nuclei and basal metabolic rates (BMRs. In birds and mammals, larger species consistently evolved larger cells for five cell types (erythrocytes, enterocytes, chondrocytes, skin epithelial cells, and kidney proximal tubule cells and evolved smaller hepatocytes. We found no evidence that cell size differences originated through genome size changes. We conclude that the organism-wide coordination of cell size changes might be an evolutionarily conservative characteristic, and the convergent evolutionary body size and cell size changes in Galliformes and Rodentia suggest the adaptive significance of cell size. Recent theory predicts that species evolving larger cells waste less energy on tissue maintenance but have reduced capacities to deliver oxygen to mitochondria and metabolize resources. Indeed, birds with larger size of the abovementioned cell types and smaller hepatocytes have evolved lower mass-specific BMRs. We propose that the inconsistent pattern in hepatocytes derives from the efficient delivery system to hepatocytes, combined with their intense involvement in supracellular function and anabolic activity.

  11. The body size of the oil-collecting bee Tetrapedia diversipes (Apidae)

    OpenAIRE

    Pinto da Silva,Carlos; Silva,Adriana; Duran Cordeiro,Guaraci; Alves dos Santos ,Isabel

    2015-01-01

    The body size of bees can affect their fitness in many ways. There is an indirect relationship between the size of the mother and the size of her progeny. This is so because large mothers use larger nests and brood cells and have higher foraging capacity than small mothers, and consequently large mothers supply a larger amount of food to their larvae, which grow larger. We analyzed the relationship between body size of individual oil-collecting bees of the species Tetrapedia diversipes and th...

  12. Body Size Shifts in Philippine Reef Fishes: Interfamilial Variation in Responses to Protection

    Directory of Open Access Journals (Sweden)

    Robert Y. Fidler

    2014-03-01

    Full Text Available As a consequence of intense fishing pressure, fished populations experience reduced population sizes and shifts in body size toward the predominance of smaller and early maturing individuals. Small, early-maturing fish exhibit significantly reduced reproductive output and, ultimately, reduced fitness. As part of resource management and biodiversity conservation programs worldwide, no-take marine protected areas (MPAs are expected to ameliorate the adverse effects of fishing pressure. In an attempt to advance our understanding of how coral reef MPAs meet their long-term goals, this study used visual census data from 23 MPAs and fished reefs in the Philippines to address three questions: (1 Do MPAs promote shifts in fish body size frequency distribution towards larger body sizes when compared to fished reefs? (2 Do MPA size and (3 age contribute to the efficacy of MPAs in promoting such shifts? This study revealed that across all MPAs surveyed, the distribution of fishes between MPAs and fished reefs were similar; however, large-bodied fish were more abundant within MPAs, along with small, young-of-the-year individuals. Additionally, there was a significant shift in body size frequency distribution towards larger body sizes in 12 of 23 individual reef sites surveyed. Of 22 fish families, eleven demonstrated significantly different body size frequency distributions between MPAs and fished reefs, indicating that shifts in the size spectrum of fishes in response to protection are family-specific. Family-level shifts demonstrated a significant, positive correlation with MPA age, indicating that MPAs become more effective at increasing the density of large-bodied fish within their boundaries over time.

  13. Body size ideals and dissatisfaction in Ghanaian adolescents: role of media, lifestyle and well-being.

    Science.gov (United States)

    Michels, N; Amenyah, S D

    2017-05-01

    To inspire effective health promotion campaigns, we tested the relationship of ideal body size and body size dissatisfaction with (1) the potential resulting health-influencing factors diet, physical activity and well-being; and (2) with media as a potential influencer of body ideals. This is a cross-sectional study in 370 Ghanaian adolescents (aged 11-18 years). Questionnaires included disordered eating (EAT26), diet quality (FFQ), physical activity (IPAQ), well-being (KINDL) and media influence on appearance (SATAQ: pressure, internalisation and information). Ideal body size and body size dissatisfaction were assessed using the Stunkard figure rating scale. Body mass index (BMI), skinfolds and waist were measured. Linear regressions were adjusted for gender, age and parental education. Also, mediation was tested: 'can perceived media influence play a role in the effects of actual body size on body size dissatisfaction?'. Body size dissatisfaction was associated with lower well-being and more media influence (pressure and internalisation) but not with physical activity, diet quality or disordered eating. An underweight body size ideal might worsen disordered eating but was not significantly related to the other predictors of interest. Only a partial mediation effect by media pressure was found: especially overweight adolescents felt media pressure, and this media pressure was associated with more body size dissatisfaction. To prevent disordered eating and low well-being, health messages should include strategies that reduce body size dissatisfaction and increase body esteem by not focussing on the thin body ideal. Changing body size ideals in the media might be an appropriate way since media pressure was a mediator in the BMI-dissatisfaction relation. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  14. Adjusting parameters of aortic valve stenosis severity by body size

    DEFF Research Database (Denmark)

    Minners, Jan; Gohlke-Baerwolf, Christa; Kaufmann, Beat A

    2014-01-01

    stenosis (jet velocity ≥2.5 m/s) and related to outcomes in a second cohort of 1525 patients from the Simvastatin/Ezetimibe in Aortic Stenosis (SEAS) study. RESULTS: Whereas jet velocity and MPG were independent of body size, AVA was significantly correlated with height, weight, BSA and BMI (Pearson...... correlation coefficient (r) 0.319, 0.281, 0.317 and 0.126, respectively, all pcorrelation between AVA and body size...

  15. Body Size Preference of Marine Animals in Relation to Extinction Selectivity

    Science.gov (United States)

    Sriram, A.; Idgunji, S.; Heim, N. A.; Payne, J.

    2014-12-01

    Our project encompasses an extremely specific aspect in relation to the five mass extinctions in geologic history. We asked ourselves whether larger or smaller body sizes would be better suited for surviving a mass extinction. To conduct research for our project, we used the body sizes of 17,172 marine animal genera as our primary data. These animals include echinoderms, arthropods, chordates, mollusks, and brachiopods. These creatures are perfect model organisms in terms of finding data on them because they have an excellent fossil record, and are well documented. We focused on the mean body size of these animals before and after each of the five mass extinctions (end-Ordovician, Late Devonian, end-Permian, end-Triassic, and end-Cretaceous). Our hypothesis was that the average biovolume of animals increased after each of the extinctions, with the mean size being greater after than it was before. Our size data is from the Ellis & Messina Catalogue of Ostracoda and the Treatise on Invertebrate Paleontology. We obtained stratigraphic range data The Treatise and Sepkoski (2002). In our analyses, we compared the mean size of the different animal genera before and after each extinction event. We further partitioned size change across mass extinction boundaries into three categories: the surviving genera, the extinct genera, and the newly originating genera that came about after the extinction. According to our analyses, the mean sizes did not change significantly from the genera living during the stages before the extinctions and after the extinctions. From our results, we can assume that there were not enough major increases in the overall volume of the organisms to warrant a definite conclusion that extinctions lead to larger body sizes. Further support for our findings came from the T-tests in our R code. Only the Cretaceous period showed true evidence for size changing because of the extinction; in this case, the mean size decreased. T-tests for the Cretaceous

  16. Spatial variation in egg size of a top predator: Interplay of body size and environmental factors?

    Science.gov (United States)

    Louzao, Maite; Igual, José M.; Genovart, Meritxell; Forero, Manuela G.; Hobson, Keith A.; Oro, Daniel

    2008-09-01

    It is expected that nearby populations are constrained by the same ecological features shaping in turn similarity in their ecological traits. Here, we studied the spatio-temporal variability in egg size among local populations of the critically endangered Balearic shearwater Puffinus mauretanicus, a top marine predator endemic to the western Mediterranean region. Specifically we assessed whether this trait was influenced by maternal body size, as an indicator of a genetic component, and feeding ecology (through stable-carbon and nitrogen-isotope measurements), as an indicator of environmental factors. We found that egg size varied among local populations, an unexpected result at such a small spatial scale. Body size differences at the local population level only partially explained such differences. Blood isotope measurements also differed among local populations. Values of δ 15N suggested inter-population differences in trophic level, showing a similar general pattern with egg size, and suggesting a nutritional link between them whereby egg size was affected by differences in feeding resources and/or behaviour. Values of δ 13C suggested that local populations did not differ in foraging habits with respect to benthic- vs. pelagic-based food-webs. Egg size did not vary among years as did breeding performance, suggesting that a differential temporal window could affect both breeding parameters in relation to food availability. The absence of a relationship between breeding performance and egg size suggested that larger eggs might only confer an advantage during harsh conditions. Alternatively parental quality could greatly affect breeding performance. We showed that inter-population differences in egg size could be influenced by both body size and environmental factors.

  17. Illusory changes in body size modulate body satisfaction in a way that is related to non-clinical eating disorder psychopathology.

    Directory of Open Access Journals (Sweden)

    Catherine Preston

    Full Text Available Historically, body size overestimation has been linked to abnormal levels of body dissatisfaction found in eating disorders. However, recently this relationship has been called into question. Indeed, despite a link between how we perceive and how we feel about our body seeming intuitive, until now lack of an experimental method to manipulate body size has meant that a causal link, even in healthy participants, has remained elusive. Recent developments in body perception research demonstrate that the perceptual experience of the body can be readily manipulated using multisensory illusions. The current study exploits such illusions to modulate perceived body size in an attempt to influence body satisfaction. Participants were presented with stereoscopic video images of slimmer and wider mannequin bodies viewed through head-mounted displays from first person perspective. Illusory ownership was induced by synchronously stroking the seen mannequin body with the unseen real body. Pre and post-illusion affective and perceptual measures captured changes in perceived body size and body satisfaction. Illusory ownership of a slimmer body resulted in participants perceiving their actual body as slimmer and giving higher ratings of body satisfaction demonstrating a direct link between perceptual and affective body representations. Change in body satisfaction following illusory ownership of a wider body, however, was related to degree of (non-clinical eating disorder psychopathology, which can be linked to fluctuating body representations found in clinical samples. The results suggest that body perception is linked to body satisfaction and may be of importance for eating disorder symptomology.

  18. Illusory Changes in Body Size Modulate Body Satisfaction in a Way That Is Related to Non-Clinical Eating Disorder Psychopathology

    Science.gov (United States)

    Preston, Catherine; Ehrsson, H. Henrik

    2014-01-01

    Historically, body size overestimation has been linked to abnormal levels of body dissatisfaction found in eating disorders. However, recently this relationship has been called into question. Indeed, despite a link between how we perceive and how we feel about our body seeming intuitive, until now lack of an experimental method to manipulate body size has meant that a causal link, even in healthy participants, has remained elusive. Recent developments in body perception research demonstrate that the perceptual experience of the body can be readily manipulated using multisensory illusions. The current study exploits such illusions to modulate perceived body size in an attempt to influence body satisfaction. Participants were presented with stereoscopic video images of slimmer and wider mannequin bodies viewed through head-mounted displays from first person perspective. Illusory ownership was induced by synchronously stroking the seen mannequin body with the unseen real body. Pre and post-illusion affective and perceptual measures captured changes in perceived body size and body satisfaction. Illusory ownership of a slimmer body resulted in participants perceiving their actual body as slimmer and giving higher ratings of body satisfaction demonstrating a direct link between perceptual and affective body representations. Change in body satisfaction following illusory ownership of a wider body, however, was related to degree of (non-clinical) eating disorder psychopathology, which can be linked to fluctuating body representations found in clinical samples. The results suggest that body perception is linked to body satisfaction and may be of importance for eating disorder symptomology. PMID:24465698

  19. Aging and body size in solitary bees

    Science.gov (United States)

    Solitary bees are important pollinators of crops and non-domestic plants. Osmia lignaria is a native, commercially-reared solitary bee used to maximize pollination in orchard crops. In solitary bees, adult body size is extremely variable depending on the nutritional resources available to the develo...

  20. Body Size Mediated Coexistence in Swans

    Directory of Open Access Journals (Sweden)

    Katharina A. M. Engelhardt

    2014-01-01

    Full Text Available Differences in body sizes may create a trade-off between foraging efficiency (foraging gains/costs and access to resources. Such a trade-off provides a potential mechanism for ecologically similar species to coexist on one resource. We explored this hypothesis for tundra (Cygnus columbianus and trumpeter swans (Cygnus buccinator, a federally protected species, feeding solely on sago pondweed (Stuckenia pectinata tubers during fall staging and wintering in northern Utah. Foraging efficiency was higher for tundra swans because this species experienced lower foraging and metabolic costs relative to foraging gains; however, trumpeter swans (a had longer necks and therefore had access to exclusive resources buried deep in wetland sediments and (b were more aggressive and could therefore displace tundra swans from lucrative foraging locations. We conclude that body size differentiation is an important feature of coexistence among ecologically similar species feeding on one resource. In situations where resources are limiting and competition for resources is strong, conservation managers will need to consider the trade-off between foraging efficiency and access to resources to ensure ecologically similar species can coexist on a shared resource.

  1. Big or fast: two strategies in the developmental control of body size

    OpenAIRE

    Nijhout, H. Frederik

    2015-01-01

    Adult body size is controlled by the mechanisms that stop growth when a species-characteristic size has been reached. The mechanisms by which size is sensed and by which this information is transduced to the growth regulating system are beginning to be understood in a few species of insects. Two rather different strategies for control have been discovered; one favors large body size and the other favors rapid development.

  2. Body size and body esteem in women : The mediating role of possible self expectancy

    NARCIS (Netherlands)

    Dalley, Simon E.; Pollet, Thomas V.; Vidal, Jose

    We predicted that an expectancy of acquiring a feared fat self and an expectancy of acquiring a hoped-for thin self both mediate the impact of body size on women's body esteem. We also predicted that the mediating pathway through the feared fat self would be stronger than that through the hoped-for

  3. Body size and body esteem in women: The mediating role of possible self expectancy

    NARCIS (Netherlands)

    Dalley, S.E.; Pollet, T.V.; Vidal, J.

    2013-01-01

    We predicted that an expectancy of acquiring a feared fat self and an expectancy of acquiring a hoped-for thin self both mediate the impact of body size on women's body esteem. We also predicted that the mediating pathway through the feared fat self would be stronger than that through the hoped-for

  4. Body size limits dim-light foraging activity in stingless bees (Apidae: Meliponini).

    Science.gov (United States)

    Streinzer, Martin; Huber, Werner; Spaethe, Johannes

    2016-10-01

    Stingless bees constitute a species-rich tribe of tropical and subtropical eusocial Apidae that act as important pollinators for flowering plants. Many foraging tasks rely on vision, e.g. spatial orientation and detection of food sources and nest entrances. Meliponini workers are usually small, which sets limits on eye morphology and thus quality of vision. Limitations are expected both on acuity, and thus on the ability to detect objects from a distance, as well as on sensitivity, and thus on the foraging time window at dusk and dawn. In this study, we determined light intensity thresholds for flight under dim light conditions in eight stingless bee species in relation to body size in a Neotropical lowland rainforest. Species varied in body size (0.8-1.7 mm thorax-width), and we found a strong negative correlation with light intensity thresholds (0.1-79 lx). Further, we measured eye size, ocelli diameter, ommatidia number, and facet diameter. All parameters significantly correlated with body size. A disproportionately low light intensity threshold in the minute Trigonisca pipioli, together with a large eye parameter P eye suggests specific adaptations to circumvent the optical constraints imposed by the small body size. We discuss the implications of body size in bees on foraging behavior.

  5. Low level of polyandry constrains phenotypic plasticity of male body size in mites.

    Directory of Open Access Journals (Sweden)

    Peter Schausberger

    Full Text Available Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis. We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i the effects of male body size on spermatophore transfer in singly mating females and (ii the effects of mate sequence (switching the order of standard-sized and small males on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard-sized

  6. Low level of polyandry constrains phenotypic plasticity of male body size in mites.

    Science.gov (United States)

    Schausberger, Peter; Walzer, Andreas; Murata, Yasumasa; Osakabe, Masahiro

    2017-01-01

    Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female) is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis). We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i) the effects of male body size on spermatophore transfer in singly mating females and (ii) the effects of mate sequence (switching the order of standard-sized and small males) on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard-sized males was

  7. Rule reversal: Ecogeographical patterns of body size variation in the common treeshrew (Mammalia, Scandentia)

    Science.gov (United States)

    Sargis, Eric J.; Millien, Virginie; Woodman, Neal; Olson, Link E.

    2018-01-01

    There are a number of ecogeographical “rules” that describe patterns of geographical variation among organisms. The island rule predicts that populations of larger mammals on islands evolve smaller mean body size than their mainland counterparts, whereas smaller‐bodied mammals evolve larger size. Bergmann's rule predicts that populations of a species in colder climates (generally at higher latitudes) have larger mean body sizes than conspecifics in warmer climates (at lower latitudes). These two rules are rarely tested together and neither has been rigorously tested in treeshrews, a clade of small‐bodied mammals in their own order (Scandentia) broadly distributed in mainland Southeast Asia and on islands throughout much of the Sunda Shelf. The common treeshrew, Tupaia glis, is an excellent candidate for study and was used to test these two rules simultaneously for the first time in treeshrews. This species is distributed on the Malay Peninsula and several offshore islands east, west, and south of the mainland. Using craniodental dimensions as a proxy for body size, we investigated how island size, distance from the mainland, and maximum sea depth between the mainland and the islands relate to body size of 13 insular T. glis populations while also controlling for latitude and correlation among variables. We found a strong negative effect of latitude on body size in the common treeshrew, indicating the inverse of Bergmann's rule. We did not detect any overall difference in body size between the island and mainland populations. However, there was an effect of island area and maximum sea depth on body size among island populations. Although there is a strong latitudinal effect on body size, neither Bergmann's rule nor the island rule applies to the common treeshrew. The results of our analyses demonstrate the necessity of assessing multiple variables simultaneously in studies of ecogeographical rules.

  8. Body composition of freshwater Wallago attu in relation to body size ...

    African Journals Online (AJOL)

    Wallago attu is one of the large freshwater catfish found in Pakistan. The rapid growth and high nutritional quality encouraged investigation into the aquaculture potential of this excellent food fish. It was observed that body size had a positive influence on percent ash, percent fat and percent protein contents (wet weight) but ...

  9. Comparing fishers' and scientific estimates of size at maturity and maximum body size as indicators for overfishing.

    Science.gov (United States)

    Mclean, Elizabeth L; Forrester, Graham E

    2018-04-01

    We tested whether fishers' local ecological knowledge (LEK) of two fish life-history parameters, size at maturity (SAM) at maximum body size (MS), was comparable to scientific estimates (SEK) of the same parameters, and whether LEK influenced fishers' perceptions of sustainability. Local ecological knowledge was documented for 82 fishers from a small-scale fishery in Samaná Bay, Dominican Republic, whereas SEK was compiled from the scientific literature. Size at maturity estimates derived from LEK and SEK overlapped for most of the 15 commonly harvested species (10 of 15). In contrast, fishers' maximum size estimates were usually lower than (eight species), or overlapped with (five species) scientific estimates. Fishers' size-based estimates of catch composition indicate greater potential for overfishing than estimates based on SEK. Fishers' estimates of size at capture relative to size at maturity suggest routine inclusion of juveniles in the catch (9 of 15 species), and fishers' estimates suggest that harvested fish are substantially smaller than maximum body size for most species (11 of 15 species). Scientific estimates also suggest that harvested fish are generally smaller than maximum body size (13 of 15), but suggest that the catch is dominated by adults for most species (9 of 15 species), and that juveniles are present in the catch for fewer species (6 of 15). Most Samaná fishers characterized the current state of their fishery as poor (73%) and as having changed for the worse over the past 20 yr (60%). Fishers stated that concern about overfishing, catching small fish, and catching immature fish contributed to these perceptions, indicating a possible influence of catch-size composition on their perceptions. Future work should test this link more explicitly because we found no evidence that the minority of fishers with more positive perceptions of their fishery reported systematically different estimates of catch-size composition than those with the more

  10. Prolificacy and Its Relationship with Age, Body Weight, Parity, Previous Litter Size and Body Linear Type Traits in Meat-type Goats

    Directory of Open Access Journals (Sweden)

    Avijit Haldar

    2014-05-01

    Full Text Available Data on age and body weight at breeding, parity, previous litter size, days open and some descriptive body linear traits from 389 meat-type, prolific Black Bengal goats in Tripura State of India, were collected for 3 and 1/2 years (2007 to 2010 and analyzed using logistic regression model. The objectives of the study were i to evaluate the effect of age and body weight at breeding, parity, previous litter size and days open on litter size of does; and ii to investigate if body linear type traits influenced litter size in meat-type, prolific goats. The incidence of 68.39% multiple births with a prolificacy rate of 175.07% was recorded. Higher age (>2.69 year, higher parity order (>2.31, more body weight at breeding (>20.5 kg and larger previous litter size (>1.65 showed an increase likelihood of multiple litter size when compared to single litter size. There was a strong, positive relationship between litter size and various body linear type traits like neck length (>22.78 cm, body length (>54.86 cm, withers height (>48.85 cm, croup height (>50.67 cm, distance between tuber coxae bones (>11.38 cm and distance between tuber ischii bones (>4.56 cm for discriminating the goats bearing multiple fetuses from those bearing a single fetus.

  11. The evolution of body size in extant groups of North American freshwater fishes: speciation, size distributions, and Cope's rule.

    Science.gov (United States)

    Knouft, Jason H; Page, Lawrence M

    2003-03-01

    Change in body size within an evolutionary lineage over time has been under investigation since the synthesis of Cope's rule, which suggested that there is a tendency for mammals to evolve larger body size. Data from the fossil record have subsequently been examined for several other taxonomic groups to determine whether they also displayed an evolutionary increase in body size. However, we are not aware of any species-level study that has investigated the evolution of body size within an extant continental group. Data acquired from the fossil record and data derived from the evolutionary relationships of extant species are not similar, with each set exhibiting both strengths and weaknesses related to inferring evolutionary patterns. Consequently, expectation that general trends exhibited in the fossil record will correspond to patterns in extant groups is not necessarily warranted. Using phylogenetic relationships of extant species, we show that five of nine families of North American freshwater fishes exhibit an evolutionary trend of decreasing body size. These trends result from the basal position of large species and the more derived position of small species within families. Such trends may be caused by the invasion of small streams and subsequent isolation and speciation. This pattern, potentially influenced by size-biased dispersal rates and the high percentage of small streams in North America, suggests a scenario that could result in the generation of the size-frequency distribution of North American freshwater fishes.

  12. German and English Bodies: No Evidence for Cross-Linguistic Differences in Preferred Orthographic Grain Size

    Directory of Open Access Journals (Sweden)

    Xenia Schmalz

    2017-03-01

    Full Text Available Previous studies have found that words and nonwords with many body neighbours (i.e., words with the same orthographic body, e.g., 'cat, brat, at' are read faster than items with fewer body neighbours. This body-N effect has been explored in the context of cross-linguistic differences in reading where it has been reported that the size of the effect differs as a function of orthographic depth: readers of English, a deep orthography, show stronger facilitation than readers of German, a shallow orthography. Such findings support the psycholinguistic grain size theory, which proposes that readers of English rely on large orthographic units to reduce ambiguity of print-to-speech correspondences in their orthography. Here we re-examine the evidence for this pattern and find that there is no reliable evidence for such a cross-linguistic difference. Re-analysis of a key study (Ziegler et al., 2001, analysis of data from the English Lexicon Project (Balota et al., 2007, and a large-scale analysis of nine new experiments all support this conclusion. Using Bayesian analysis techniques, we find little evidence of the body-N effect in most tasks and conditions. Where we do find evidence for a body-N effect (lexical decision for nonwords, we find evidence against an interaction with language.

  13. Do sex, body size and reproductive condition influence the thermal preferences of a large lizard? A study in Tupinambis merianae.

    Science.gov (United States)

    Cecchetto, Nicolas Rodolfo; Naretto, Sergio

    2015-10-01

    Body temperature is a key factor in physiological processes, influencing lizard performances; and life history traits are expected to generate variability of thermal preferences in different individuals. Gender, body size and reproductive condition may impose specific requirements on preferred body temperatures. If these three factors have different physiological functions and thermal requirements, then the preferred temperature may represent a compromise that optimizes these physiological functions. Therefore, the body temperatures that lizards select in a controlled environment may reflect a temperature that maximizes their physiological needs. The tegu lizard Tupinambis merianae is one of the largest lizards in South America and has wide ontogenetic variation in body size and sexual dimorphism. In the present study we evaluate intraspecific variability of thermal preferences of T. merianae. We determined the selected body temperature and the rate at which males and females attain their selected temperature, in relation to body size and reproductive condition. We also compared the behavior in the thermal gradient between males and females and between reproductive condition of individuals. Our study show that T. merianae selected body temperature within a narrow range of temperatures variation in the laboratory thermal gradient, with 36.24±1.49°C being the preferred temperature. We observed no significant differences between sex, body size and reproductive condition in thermal preferences. Accordingly, we suggest that the evaluated categories of T. merianae have similar thermal requirements. Males showed higher rates to obtain heat than females and reproductive females, higher rates than non-reproductive ones females. Moreover, males and reproductive females showed a more dynamic behavior in the thermal gradient. Therefore, even though they achieve the same selected temperature, they do it differentially. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Heritability of body size in the polar bears of Western Hudson Bay.

    Science.gov (United States)

    Malenfant, René M; Davis, Corey S; Richardson, Evan S; Lunn, Nicholas J; Coltman, David W

    2018-04-18

    Among polar bears (Ursus maritimus), fitness is dependent on body size through males' abilities to win mates, females' abilities to provide for their young and all bears' abilities to survive increasingly longer fasting periods caused by climate change. In the Western Hudson Bay subpopulation (near Churchill, Manitoba, Canada), polar bears have declined in body size and condition, but nothing is known about the genetic underpinnings of body size variation, which may be subject to natural selection. Here, we combine a 4449-individual pedigree and an array of 5,433 single nucleotide polymorphisms (SNPs) to provide the first quantitative genetic study of polar bears. We used animal models to estimate heritability (h 2 ) among polar bears handled between 1966 and 2011, obtaining h 2 estimates of 0.34-0.48 for strictly skeletal traits and 0.18 for axillary girth (which is also dependent on fatness). We genotyped 859 individuals with the SNP array to test for marker-trait association and combined p-values over genetic pathways using gene-set analysis. Variation in all traits appeared to be polygenic, but we detected one region of moderately large effect size in body length near a putative noncoding RNA in an unannotated region of the genome. Gene-set analysis suggested that variation in body length was associated with genes in the regulatory cascade of cyclin expression, which has previously been associated with body size in mice. A greater understanding of the genetic architecture of body size variation will be valuable in understanding the potential for adaptation in polar bear populations challenged by climate change. © 2018 John Wiley & Sons Ltd.

  15. Body shape and size depictions of African American women in JET magazine, 1953-2006.

    Science.gov (United States)

    Dawson-Andoh, Nana A; Gray, James J; Soto, José A; Parker, Scott

    2011-01-01

    Depictions of Caucasian women in the mainstream media have become increasingly thinner in size and straighter in shape. These changes may be inconsistent with the growing influence of African American beauty ideals, which research has established as more accepting of larger body sizes and more curvaceous body types than Caucasians. The present study looked at trends in the portrayal of African American women featured in JET magazine from 1953 to 2006. Beauty of the Week (BOW) images were collected and analyzed to examine body size (estimated by independent judges) and body shape (estimated by waist-to-hip ratio). We expected body sizes to increase and body shapes to become more curvaceous. Results revealed a rise in models' body size consistent with expectations, but an increase in waist-to-hip ratio, contrary to prediction. Our findings suggest that the African American feminine beauty ideal reflects both consistencies with and departures from mainstream cultural ideals. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Functional size analysis of bioactive materials by radiation inactivation

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    1994-01-01

    When the research on various proteins including enzymes is carried out, first molecular weight is measured. The physical chemical methods used for measuring molecular weight cannot measure it in the state of actually acting in living bodies. Radiation inactivation method is the unique method which can measure the molecular weight of the active substances in living bodies. Paying attention to this point, recently it is attempted to measure the activity unit of enzymes, receptors and others, and to apply to the elucidation of their functions. In this report, the concept of the method of measuring molecular size based on radiation inactivation, the detailed experimental method and the points to which attention must be paid are described. Also its application to the elucidation of living body functions according to the example of the studies by the author is reported. The concept of the measurement of molecular weight by radiation inactivation is based on target theory. The preparation of samples, the effect of oxygen, radiation sources, dosimetry, irradiation temperature, internal standard process and so on are reported. The trend of the research is shown. (K.I.)

  17. Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

    Science.gov (United States)

    Tucker, Marlee A.; Rogers, Tracey L.

    2014-01-01

    Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities. PMID:25377460

  18. Can foraging ecology drive the evolution of body size in a diving endotherm?

    Directory of Open Access Journals (Sweden)

    Timothée R Cook

    Full Text Available Within a single animal species, different morphs can allow for differential exploitation of foraging niches between populations, while sexual size dimorphism can provide each sex with access to different resources. Despite being potentially important agents of evolution, resource polymorphisms, and the way they operate in wild populations, remain poorly understood. In this study, we examine how trophic factors can select for different body sizes between populations and sexes in a diving endotherm. Dive depth and duration are positively related to body size in diving birds and mammals, a relationship explained by a lower mass-specific metabolic rate and greater oxygen stores in larger individuals. Based on this allometry, we predict that selection for exploiting resources situated at different depths can drive the evolution of body size in species of diving endotherms at the population and sexual level. To test this prediction, we studied the foraging ecology of Blue-eyed Shags, a group of cormorants with male-biased sexual size dimorphism from across the Southern Ocean. We found that mean body mass and relative difference in body mass between sexes varied by up to 77% and 107% between neighbouring colonies, respectively. Birds from colonies with larger individuals dived deeper than birds from colonies with smaller individuals, when accounting for sex. In parallel, males dived further offshore and deeper than females and the sexual difference in dive depth reflected the level of sexual size dimorphism at each colony. We argue that body size in this group of birds is under intense selection for diving to depths of profitable benthic prey patches and that, locally, sexual niche divergence selection can exaggerate the sexual size dimorphism of Blue-eyed Shags initially set up by sexual selection. Our findings suggest that trophic resources can select for important geographic micro-variability in body size between populations and sexes.

  19. Body size correlates with fertilization success but not gonad size in grass goby territorial males.

    Directory of Open Access Journals (Sweden)

    Jose Martin Pujolar

    Full Text Available In fish species with alternative male mating tactics, sperm competition typically occurs when small males that are unsuccessful in direct contests steal fertilization opportunities from large dominant males. In the grass goby Zosterisessor ophiocephalus, large territorial males defend and court females from nest sites, while small sneaker males obtain matings by sneaking into nests. Parentage assignment of 688 eggs from 8 different nests sampled in the 2003-2004 breeding season revealed a high level of sperm competition. Fertilization success of territorial males was very high but in all nests sneakers also contributed to the progeny. In territorial males, fertilization success correlated positively with male body size. Gonadal investment was explored in a sample of 126 grass gobies collected during the period 1995-1996 in the same area (61 territorial males and 65 sneakers. Correlation between body weight and testis weight was positive and significant for sneaker males, while correlation was virtually equal to zero in territorial males. That body size in territorial males is correlated with fertilization success but not gonad size suggests that males allocate much more energy into growth and relatively little into sperm production once the needed size to become territorial is attained. The increased paternity of larger territorial males might be due to a more effective defense of the nest in comparison with smaller territorial males.

  20. Body size correlates with fertilization success but not gonad size in grass goby territorial males.

    Science.gov (United States)

    Pujolar, Jose Martin; Locatello, Lisa; Zane, Lorenzo; Mazzoldi, Carlotta

    2012-01-01

    In fish species with alternative male mating tactics, sperm competition typically occurs when small males that are unsuccessful in direct contests steal fertilization opportunities from large dominant males. In the grass goby Zosterisessor ophiocephalus, large territorial males defend and court females from nest sites, while small sneaker males obtain matings by sneaking into nests. Parentage assignment of 688 eggs from 8 different nests sampled in the 2003-2004 breeding season revealed a high level of sperm competition. Fertilization success of territorial males was very high but in all nests sneakers also contributed to the progeny. In territorial males, fertilization success correlated positively with male body size. Gonadal investment was explored in a sample of 126 grass gobies collected during the period 1995-1996 in the same area (61 territorial males and 65 sneakers). Correlation between body weight and testis weight was positive and significant for sneaker males, while correlation was virtually equal to zero in territorial males. That body size in territorial males is correlated with fertilization success but not gonad size suggests that males allocate much more energy into growth and relatively little into sperm production once the needed size to become territorial is attained. The increased paternity of larger territorial males might be due to a more effective defense of the nest in comparison with smaller territorial males.

  1. Galectin-3 levels relate in children to total body fat, abdominal fat, body fat distribution, and cardiac size.

    Science.gov (United States)

    Dencker, Magnus; Arvidsson, Daniel; Karlsson, Magnus K; Wollmer, Per; Andersen, Lars B; Thorsson, Ola

    2018-03-01

    Galectin-3 has recently been proposed as a novel biomarker for cardiovascular disease in adults. The purpose of this investigation was to assess relationships between galectin-3 levels and total body fat, abdominal fat, body fat distribution, aerobic fitness, blood pressure, left ventricular mass, left atrial size, and increase in body fat over a 2-year period in a population-based sample of children. Our study included 170 children aged 8-11 years. Total fat mass and abdominal fat were measured by dual-energy x-ray absorptiometry (DXA). Body fat distribution was expressed as abdominal fat/total fat mass. Maximal oxygen uptake was assessed by indirect calorimetry during a maximal exercise test and scaled to body mass. Systolic and diastolic blood pressure and pulse pressure were measured. Left atrial size, left ventricular mass, and relative wall thickness were measured by echocardiography. Frozen serum samples were analyzed for galectin-3 by the Proximity Extension Assay technique. A follow-up DXA scan was performed in 152 children 2 years after the baseline exam. Partial correlations, with adjustment for sex and age, between galectin-3 versus body fat measurements indicated weak to moderate relationships. Moreover, left atrial size, left ventricular mass, and relative wall thickness and pulse pressure were also correlated with galectin-3. Neither systolic blood pressure nor maximal oxygen uptake was correlated with galectin-3. There was also a correlation between galectin-3 and increase in total body fat over 2 years, while no such correlations were found for the other fat measurements. More body fat and abdominal fat, more abdominal body fat distribution, more left ventricular mass, and increased left atrial size were all associated with higher levels of galectin-3. Increase in total body fat over 2 years was also associated with higher levels of galectin-3. What is Known: • Galectin-3 has been linked to obesity and been proposed to be a novel biomarker

  2. A pilot study on body image, attractiveness and body size in Gambians living in an urban community.

    Science.gov (United States)

    Siervo, M; Grey, P; Nyan, O A; Prentice, A M

    2006-06-01

    We investigated the attitudinal and perceptual components of body image and its link with body mass index (BMI) in a sample of urban Gambians. We also looked at cross-cultural differences in body image and views on attractiveness between Gambians and Americans. Four groups of 50 subjects were assessed: men 14- 25y (YM); women 14-25y (YW); men 35-50y (OM); women 35-50y (OW). Socio-economic status, education, healthy lifestyle and western influences were investigated. Height and weight were measured. Body dissatisfaction was assessed with the body dissatisfaction scale of the Eating Disorder Inventory. Perceptions of body image and attractiveness were assessed using the Body Image Assessment for Obesity (BIA-O) and Figure Rating Scale (FRS). Different generations of Gambians had very different perceptions and attitudes towards obesity. Current body size was realistically perceived and largely well tolerated. Older women had a higher body discrepancy (current minus ideal body size) than other groups (pbody size until they were overweight (BMI=27.8 kg/m2), whilst OM, YM and YW started to be concerned at a BMI respectively of 22.9, 19.8 and 21.5 kg/m2. A cross-cultural comparison using published data on FRS showed that Gambians were more obesity tolerant than black and white Americans. The Gambia is a country in the early stage of demographic transitions but in urban areas there is an increase in obesity prevalence. Inherent tensions between the preservation of cultural values and traditional habits, and raising awareness of the risks of obesity, may limit health interventions to prevent weight gain.

  3. Environmental, biological and anthropogenic effects on grizzly bear body size: temporal and spatial considerations.

    Science.gov (United States)

    Nielsen, Scott E; Cattet, Marc R L; Boulanger, John; Cranston, Jerome; McDermid, Greg J; Shafer, Aaron B A; Stenhouse, Gordon B

    2013-09-08

    Individual body growth is controlled in large part by the spatial and temporal heterogeneity of, and competition for, resources. Grizzly bears (Ursus arctos L.) are an excellent species for studying the effects of resource heterogeneity and maternal effects (i.e. silver spoon) on life history traits such as body size because their habitats are highly variable in space and time. Here, we evaluated influences on body size of grizzly bears in Alberta, Canada by testing six factors that accounted for spatial and temporal heterogeneity in environments during maternal, natal and 'capture' (recent) environments. After accounting for intrinsic biological factors (age, sex), we examined how body size, measured in mass, length and body condition, was influenced by: (a) population density; (b) regional habitat productivity; (c) inter-annual variability in productivity (including silver spoon effects); (d) local habitat quality; (e) human footprint (disturbances); and (f) landscape change. We found sex and age explained the most variance in body mass, condition and length (R(2) from 0.48-0.64). Inter-annual variability in climate the year before and of birth (silver spoon effects) had detectable effects on the three-body size metrics (R(2) from 0.04-0.07); both maternal (year before birth) and natal (year of birth) effects of precipitation and temperature were related with body size. Local heterogeneity in habitat quality also explained variance in body mass and condition (R(2) from 0.01-0.08), while annual rate of landscape change explained additional variance in body length (R(2) of 0.03). Human footprint and population density had no observed effect on body size. These results illustrated that body size patterns of grizzly bears, while largely affected by basic biological characteristics (age and sex), were also influenced by regional environmental gradients the year before, and of, the individual's birth thus illustrating silver spoon effects. The magnitude of the silver

  4. Influence of adult nutrition on the relationship between body size and reproductive parameters in a parasitoid wasp

    NARCIS (Netherlands)

    Bezemer, T.M.; Harvey, J.A.; Mills, N.J.

    2005-01-01

    1. An important constraint upon life-history evolution in parasitoids is the limit imposed by body size on allocation of limited metabolic resources to different fitness-related physiological functions such as reproduction and survival. 2. The influence of adult nutrition on reproductive and

  5. Form or function: Does focusing on body functionality protect women from body dissatisfaction when viewing media images?

    Science.gov (United States)

    Mulgrew, Kate E; Tiggemann, Marika

    2018-01-01

    We examined whether shifting young women's ( N =322) attention toward functionality components of media-portrayed idealized images would protect against body dissatisfaction. Image type was manipulated via images of models in either an objectified body-as-object form or active body-as-process form; viewing focus was manipulated via questions about the appearance or functionality of the models. Social comparison was examined as a moderator. Negative outcomes were most pronounced within the process-related conditions (body-as-process images or functionality viewing focus) and for women who reported greater functionality comparison. Results suggest that functionality-based depictions, reflections, and comparisons may actually produce worse outcomes than those based on appearance.

  6. Body size reductions in nonmammalian eutheriodont therapsids (Synapsida) during the end-Permian mass extinction.

    Science.gov (United States)

    Huttenlocker, Adam K

    2014-01-01

    The extent to which mass extinctions influence body size evolution in major tetrapod clades is inadequately understood. For example, the 'Lilliput effect,' a common feature of mass extinctions, describes a temporary decrease in body sizes of survivor taxa in post-extinction faunas. However, its signature on existing patterns of body size evolution in tetrapods and the persistence of its impacts during post-extinction recoveries are virtually unknown, and rarely compared in both geologic and phylogenetic contexts. Here, I evaluate temporal and phylogenetic distributions of body size in Permo-Triassic therocephalian and cynodont therapsids (eutheriodonts) using a museum collections-based approach and time series model fitting on a regional stratigraphic sequence from the Karoo Basin, South Africa. I further employed rank order correlation tests on global age and clade rank data from an expanded phylogenetic dataset, and performed evolutionary model testing using Brownian (passive diffusion) models. Results support significant size reductions in the immediate aftermath of the end-Permian mass extinction (ca. 252.3 Ma) consistent with some definitions of Lilliput effects. However, this temporal succession reflects a pattern that was underscored largely by Brownian processes and constructive selectivity. Results also support two recent contentions about body size evolution and mass extinctions: 1) active, directional evolution in size traits is rare over macroevolutionary time scales and 2) geologically brief size reductions may be accomplished by the ecological removal of large-bodied species without rapid originations of new small-bodied clades or shifts from long-term evolutionary patterns.

  7. Patterns of diversity in soft-bodied meiofauna: dispersal ability and body size matter.

    Science.gov (United States)

    Curini-Galletti, Marco; Artois, Tom; Delogu, Valentina; De Smet, Willem H; Fontaneto, Diego; Jondelius, Ulf; Leasi, Francesca; Martínez, Alejandro; Meyer-Wachsmuth, Inga; Nilsson, Karin Sara; Tongiorgi, Paolo; Worsaae, Katrine; Todaro, M Antonio

    2012-01-01

    Biogeographical and macroecological principles are derived from patterns of distribution in large organisms, whereas microscopic ones have often been considered uninteresting, because of their supposed wide distribution. Here, after reporting the results of an intensive faunistic survey of marine microscopic animals (meiofauna) in Northern Sardinia, we test for the effect of body size, dispersal ability, and habitat features on the patterns of distribution of several groups. As a dataset we use the results of a workshop held at La Maddalena (Sardinia, Italy) in September 2010, aimed at studying selected taxa of soft-bodied meiofauna (Acoela, Annelida, Gastrotricha, Nemertodermatida, Platyhelminthes and Rotifera), in conjunction with data on the same taxa obtained during a previous workshop hosted at Tjärnö (Western Sweden) in September 2007. Using linear mixed effects models and model averaging while accounting for sampling bias and potential pseudoreplication, we found evidence that: (1) meiofaunal groups with more restricted distribution are the ones with low dispersal potential; (2) meiofaunal groups with higher probability of finding new species for science are the ones with low dispersal potential; (3) the proportion of the global species pool of each meiofaunal group present in each area at the regional scale is negatively related to body size, and positively related to their occurrence in the endobenthic habitat. Our macroecological analysis of meiofauna, in the framework of the ubiquity hypothesis for microscopic organisms, indicates that not only body size but mostly dispersal ability and also occurrence in the endobenthic habitat are important correlates of diversity for these understudied animals, with different importance at different spatial scales. Furthermore, since the Western Mediterranean is one of the best-studied areas in the world, the large number of undescribed species (37%) highlights that the census of marine meiofauna is still very far

  8. Factors determining the average body size of geographically separated Arctodiaptomus salinus (Daday, 1885) populations.

    Science.gov (United States)

    Anufriieva, Elena V; Shadrin, Nickolai V

    2014-03-01

    Arctodiaptomus salinus inhabits water bodies across Eurasia and North Africa. Based on our own data and that from the literature, we analyzed the influences of several factors on the intra- and inter-population variability of this species. A strong negative linear correlation between temperature and average body size in the Crimean and African populations was found, in which the parameters might be influenced by salinity. Meanwhile, a significant negative correlation between female body size and the altitude of habitats was found by comparing body size in populations from different regions. Individuals from environments with highly varying abiotic parameters, e.g. temporary reservoirs, had a larger body size than individuals from permanent water bodies. The changes in average body mass in populations were at 11.4 times, whereas, those in individual metabolic activities were at 6.2 times. Moreover, two size groups of A. salinus in the Crimean and the Siberian lakes were observed. The ratio of female length to male length fluctuated between 1.02 and 1.30. The average size of A. salinus in populations and its variations were determined by both genetic and environmental factors. However, the parities of these factors were unequal in either spatial or temporal scales.

  9. A Prospective Investigation of Body Size, Body Fat Composition and Colorectal Cancer Risk in the UK Biobank.

    Science.gov (United States)

    Ortega, Luisa Saldana; Bradbury, Kathryn E; Cross, Amanda J; Morris, Jessica S; Gunter, Marc J; Murphy, Neil

    2017-12-19

    Obesity has been consistently associated with a greater colorectal cancer risk, but this relationship is weaker among women. In the UK Biobank, we investigated the associations between body size (body mass index [BMI], height, waist circumference, and waist-to-hip ratio) and body fat composition (total body fat percentage and trunk fat percentage) measurements with colorectal cancer risk among 472,526 men and women followed for 5.6 years on average. Multivariable hazard ratios (HRs) and 95% confidence intervals (95%CI) for developing colorectal cancer (2,636 incident cases) were estimated using Cox proportional hazards models. Among men, when the highest and lowest fifths were compared, BMI (HR = 1.35, 95%CI: 1.13-1.61; P trend  body fat percentage (HR = 1.27, 95%CI: 1.06-1.53; P trend  = 0.002), and trunk fat percentage (HR = 1.31, 95%CI: 1.09-1.58; P trend  = 0.002) were associated with greater colorectal cancer risk. For women, only waist-to-hip ratio (HR for highest versus lowest fifth = 1.33, 95%CI: 1.08-1.65; P trend  = 0.005) was positively associated with colorectal cancer risk. Greater body size (overall and abdominal adiposity) was positively associated with colorectal cancer development in men. For women, abdominal adiposity, rather than overall body size, was associated with a greater colorectal cancer risk.

  10. Body size, swimming speed, or thermal sensitivity? Predator-imposed selection on amphibian larvae.

    Science.gov (United States)

    Gvoždík, Lumír; Smolinský, Radovan

    2015-11-02

    Many animals rely on their escape performance during predator encounters. Because of its dependence on body size and temperature, escape velocity is fully characterized by three measures, absolute value, size-corrected value, and its response to temperature (thermal sensitivity). The primary target of the selection imposed by predators is poorly understood. We examined predator (dragonfly larva)-imposed selection on prey (newt larvae) body size and characteristics of escape velocity using replicated and controlled predation experiments under seminatural conditions. Specifically, because these species experience a wide range of temperatures throughout their larval phases, we predict that larvae achieving high swimming velocities across temperatures will have a selective advantage over more thermally sensitive individuals. Nonzero selection differentials indicated that predators selected for prey body size and both absolute and size-corrected maximum swimming velocity. Comparison of selection differentials with control confirmed selection only on body size, i.e., dragonfly larvae preferably preyed on small newt larvae. Maximum swimming velocity and its thermal sensitivity showed low group repeatability, which contributed to non-detectable selection on both characteristics of escape performance. In the newt-dragonfly larvae interaction, body size plays a more important role than maximum values and thermal sensitivity of swimming velocity during predator escape. This corroborates the general importance of body size in predator-prey interactions. The absence of an appropriate control in predation experiments may lead to potentially misleading conclusions about the primary target of predator-imposed selection. Insights from predation experiments contribute to our understanding of the link between performance and fitness, and further improve mechanistic models of predator-prey interactions and food web dynamics.

  11. Influence functionals and black body radiation

    OpenAIRE

    Anglin, J. R.

    1993-01-01

    The Feynman-Vernon formalism is used to obtain a microscopic, quantum mechanical derivation of black body radiation, for a massless scalar field in 1+1 dimensions, weakly coupled to an environment of finite size. The model exhibits the absorption, thermal equilibrium, and emission properties of a canonical black body, but shows that the thermal radiation propagates outwards from the body, with the Planckian spectrum applying inside a wavefront region of finite thickness. The black body enviro...

  12. Body size reductions in nonmammalian eutheriodont therapsids (Synapsida during the end-Permian mass extinction.

    Directory of Open Access Journals (Sweden)

    Adam K Huttenlocker

    Full Text Available The extent to which mass extinctions influence body size evolution in major tetrapod clades is inadequately understood. For example, the 'Lilliput effect,' a common feature of mass extinctions, describes a temporary decrease in body sizes of survivor taxa in post-extinction faunas. However, its signature on existing patterns of body size evolution in tetrapods and the persistence of its impacts during post-extinction recoveries are virtually unknown, and rarely compared in both geologic and phylogenetic contexts. Here, I evaluate temporal and phylogenetic distributions of body size in Permo-Triassic therocephalian and cynodont therapsids (eutheriodonts using a museum collections-based approach and time series model fitting on a regional stratigraphic sequence from the Karoo Basin, South Africa. I further employed rank order correlation tests on global age and clade rank data from an expanded phylogenetic dataset, and performed evolutionary model testing using Brownian (passive diffusion models. Results support significant size reductions in the immediate aftermath of the end-Permian mass extinction (ca. 252.3 Ma consistent with some definitions of Lilliput effects. However, this temporal succession reflects a pattern that was underscored largely by Brownian processes and constructive selectivity. Results also support two recent contentions about body size evolution and mass extinctions: 1 active, directional evolution in size traits is rare over macroevolutionary time scales and 2 geologically brief size reductions may be accomplished by the ecological removal of large-bodied species without rapid originations of new small-bodied clades or shifts from long-term evolutionary patterns.

  13. Body Size Reductions in Nonmammalian Eutheriodont Therapsids (Synapsida) during the End-Permian Mass Extinction

    Science.gov (United States)

    Huttenlocker, Adam K.

    2014-01-01

    The extent to which mass extinctions influence body size evolution in major tetrapod clades is inadequately understood. For example, the ‘Lilliput effect,’ a common feature of mass extinctions, describes a temporary decrease in body sizes of survivor taxa in post-extinction faunas. However, its signature on existing patterns of body size evolution in tetrapods and the persistence of its impacts during post-extinction recoveries are virtually unknown, and rarely compared in both geologic and phylogenetic contexts. Here, I evaluate temporal and phylogenetic distributions of body size in Permo-Triassic therocephalian and cynodont therapsids (eutheriodonts) using a museum collections-based approach and time series model fitting on a regional stratigraphic sequence from the Karoo Basin, South Africa. I further employed rank order correlation tests on global age and clade rank data from an expanded phylogenetic dataset, and performed evolutionary model testing using Brownian (passive diffusion) models. Results support significant size reductions in the immediate aftermath of the end-Permian mass extinction (ca. 252.3 Ma) consistent with some definitions of Lilliput effects. However, this temporal succession reflects a pattern that was underscored largely by Brownian processes and constructive selectivity. Results also support two recent contentions about body size evolution and mass extinctions: 1) active, directional evolution in size traits is rare over macroevolutionary time scales and 2) geologically brief size reductions may be accomplished by the ecological removal of large-bodied species without rapid originations of new small-bodied clades or shifts from long-term evolutionary patterns. PMID:24498335

  14. The impact of psychological stress on men's judgements of female body size.

    Science.gov (United States)

    Swami, Viren; Tovée, Martin J

    2012-01-01

    Previous work has suggested that the experience of psychological stress may influence physical attractiveness ideals, but most evidence in favour of this hypothesis remains archival. The objective of this study was to experimentally investigate the impact of stress on men's judgements of female body size. Men were randomly assigned to either an experimental group, in which they took part in a task that heightened stress (experimental group, n = 41) or in which they did not take part in such a task (control group, n = 40). Both groups rated the attractiveness of female bodies varying in size from emaciated to obese, completed a measure of appetite sensation, and had their body mass indices (BMIs) measured. Between-groups analyses showed that the experimental group was matched with the control group in terms of mean age, BMI, and appetite sensation. Further analyses showed that men in the experimental group rated a significantly heavier female body size as maximally attractive than the control group. Men in the experimental group also rated heavier female bodies as more attractive and idealised a wider range of female figures than did the control group. This study found that the experience of stress was associated with a preference among men for heavier female body sizes. These results indicate that human attractiveness judgements are sensitive to variations in local ecologies and reflect adaptive strategies for dealing with changing environmental conditions.

  15. Organ doses as a function of body weight for environmental gamma rays

    International Nuclear Information System (INIS)

    Saito, Kimiaki; Petoussi, N.; Zankl, M.; Veit, R.; Jacob, P.; Drexler, G.

    1991-01-01

    The organ doses for γ rays from typical environmental sources were determined with Monte Carlo calculations using anthropomorphic phantoms having different body sizes. It has been suggested that body weight is the predominant factor influencing organ doses for environmental γ rays, regardless of sex and age. A weight function expressing organ doses for environmental γ rays was introduced. This function fitted well with the organ doses calculated using the different phantoms. The function coefficients were determined mathematically with the least squares method. On the assumption that this function was applicable to organ doses for human bodies with diverse characteristics, the variances in organ doses due to race, sex, age and difference in body weight of adults were investigated. The variations of organ doses due to race and sex were not significant. Differences in body weight were found to alter organ doses by a maximum of 10% for γ rays over 100 keV, and 20% for low-energy γ rays. The doses for organs located deep inside a body, such as ovaries, differed between a newborn baby and an adult by a maximum factor of 2 to 3. For γ rays over 100 keV, the variation was within a factor of 2 for all organs. The organ doses for adolescents more than 12 years agreed within 15% with those of the average adult. (author)

  16. Examining predator-prey body size, trophic level and body mass across marine and terrestrial mammals.

    Science.gov (United States)

    Tucker, Marlee A; Rogers, Tracey L

    2014-12-22

    Predator-prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator-prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator-prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator-prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. Allometric scaling of population variance with mean body size is predicted from Taylor's law and density-mass allometry.

    Science.gov (United States)

    Cohen, Joel E; Xu, Meng; Schuster, William S F

    2012-09-25

    Two widely tested empirical patterns in ecology are combined here to predict how the variation of population density relates to the average body size of organisms. Taylor's law (TL) asserts that the variance of the population density of a set of populations is a power-law function of the mean population density. Density-mass allometry (DMA) asserts that the mean population density of a set of populations is a power-law function of the mean individual body mass. Combined, DMA and TL predict that the variance of the population density is a power-law function of mean individual body mass. We call this relationship "variance-mass allometry" (VMA). We confirmed the theoretically predicted power-law form and the theoretically predicted parameters of VMA, using detailed data on individual oak trees (Quercus spp.) of Black Rock Forest, Cornwall, New York. These results connect the variability of population density to the mean body mass of individuals.

  18. Three-month-old human infants use vocal cues of body size.

    Science.gov (United States)

    Pietraszewski, David; Wertz, Annie E; Bryant, Gregory A; Wynn, Karen

    2017-06-14

    Differences in vocal fundamental ( F 0 ) and average formant ( F n ) frequencies covary with body size in most terrestrial mammals, such that larger organisms tend to produce lower frequency sounds than smaller organisms, both between species and also across different sex and life-stage morphs within species. Here we examined whether three-month-old human infants are sensitive to the relationship between body size and sound frequencies. Using a violation-of-expectation paradigm, we found that infants looked longer at stimuli inconsistent with the relationship-that is, a smaller organism producing lower frequency sounds, and a larger organism producing higher frequency sounds-than at stimuli that were consistent with it. This effect was stronger for fundamental frequency than it was for average formant frequency. These results suggest that by three months of age, human infants are already sensitive to the biologically relevant covariation between vocalization frequencies and visual cues to body size. This ability may be a consequence of developmental adaptations for building a phenotype capable of identifying and representing an organism's size, sex and life-stage. © 2017 The Author(s).

  19. Effects of climate on size structure and functioning of aquatic food webs

    NARCIS (Netherlands)

    Lacerot, G.

    2010-01-01

    In aquatic food webs, the role of body size is notoriously strong. It is also well known that temperature has an effect on body size. For instance, Bergmann’s rule states that body size increases from warm to cold climates. This thesis addresses the question how climate shapes the size structure of

  20. Body size and predatory performance in wolves: is bigger better?

    Science.gov (United States)

    MacNulty, Daniel R; Smith, Douglas W; Mech, L David; Eberly, Lynn E

    2009-05-01

    1. Large body size hinders locomotor performance in ways that may lead to trade-offs in predator foraging ability that limit the net predatory benefit of larger size. For example, size-related improvements in handling prey may come at the expense of pursuing prey and thus negate any enhancement in overall predatory performance due to increasing size. 2. This hypothesis was tested with longitudinal data from repeated observations of 94 individually known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park, USA. Wolf size was estimated from an individually based sex-specific growth model derived from body mass measurements of 304 wolves. 3. Larger size granted individual wolves a net predatory advantage despite substantial variation in its effect on the performance of different predatory tasks; larger size improved performance of a strength-related task (grappling and subduing elk) but failed to improve performance of a locomotor-related task (selecting an elk from a group) for wolves > 39 kg. 4. Sexual dimorphism in wolf size also explained why males outperformed females in each of the three tasks considered (attacking, selecting, and killing). 5. These findings support the generalization that bigger predators are overall better hunters, but they also indicate that increasing size ultimately limits elements of predatory behaviour that require superior locomotor performance. We argue that this could potentially narrow the dietary niche of larger carnivores as well as limit the evolution of larger size if prey are substantially more difficult to pursue than to handle.

  1. Island Rule, quantitative genetics and brain-body size evolution in Homo floresiensis.

    Science.gov (United States)

    Diniz-Filho, José Alexandre Felizola; Raia, Pasquale

    2017-06-28

    Colonization of islands often activate a complex chain of adaptive events that, over a relatively short evolutionary time, may drive strong shifts in body size, a pattern known as the Island Rule. It is arguably difficult to perform a direct analysis of the natural selection forces behind such a change in body size. Here, we used quantitative evolutionary genetic models, coupled with simulations and pattern-oriented modelling, to analyse the evolution of brain and body size in Homo floresiensis , a diminutive hominin species that appeared around 700 kya and survived up to relatively recent times (60-90 kya) on Flores Island, Indonesia. The hypothesis of neutral evolution was rejected in 97% of the simulations, and estimated selection gradients are within the range found in living natural populations. We showed that insularity may have triggered slightly different evolutionary trajectories for body and brain size, which means explaining the exceedingly small cranial volume of H. floresiensis requires additional selective forces acting on brain size alone. Our analyses also support previous conclusions that H. floresiensis may be most likely derived from an early Indonesian H. erectus , which is coherent with currently accepted biogeographical scenario for Homo expansion out of Africa. © 2017 The Author(s).

  2. Mammal extinctions, body size, and paleotemperature.

    Science.gov (United States)

    Bown, T M; Holroyd, P A; Rose, K D

    1994-10-25

    There is a general inverse relationship between the natural logarithm of tooth area (a body size indicator) of some fossil mammals and paleotemperature during approximately 2.9 million years of the early Eocene in the Bighorn Basin of northwest Wyoming. When mean temperatures became warmer, tooth areas tended to become smaller. During colder times, larger species predominated; these generally became larger or remained the same size. Paleotemperature trends also markedly affected patterns of local (and, perhaps, regional) extinction and immigration. New species appeared as immigrants during or near the hottest (smaller forms) and coldest (larger forms) intervals. Paleotemperature trend reversals commonly resulted in the ultimate extinction of both small forms (during cooling intervals) and larger forms (during warming intervals). These immigrations and extinctions mark faunal turnovers that were also modulated by sharp increases in sediment accumulation rate.

  3. Cultural constructions of "obesity": understanding body size, social class and gender in Morocco.

    Science.gov (United States)

    Batnitzky, Adina K

    2011-01-01

    This article presents data from an in-depth qualitative study of overweight and diabetic women in Morocco, a North African country experiencing a rapid increase in obesity according to national statistics. This case study explores the heterogeneous relationship among health, culture and religion in Morocco by highlighting the relationship between the intricacies of women's everyday lives and their body sizes. My findings suggest that although the Body Mass Index (BMI) of adult women has been documented to have increased in Morocco along with other macroeconomic changes (i.e., increases in urbanization, etc.), "obesity" has yet to be universally medicalized in the Moroccan context. As such women do not generally utilize a medicalized concept of obesity in reference to their larger body sizes. Rather, cultural constructions of "obesity" are understood through cultural understandings of a larger body size, religious beliefs about health and illness, and the nature of women's religious participation. This stands in contrast to dominant accounts about the region that promote an overall veneration of a larger body size for women. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Clinical correlation of radiological spinal stenosis after standardization for vertebral body size

    International Nuclear Information System (INIS)

    Athiviraham, A.; Yen, D.; Scott, C.; Soboleski, D.

    2007-01-01

    Aim: To determine the relationship between the degree of radiographic lumbar spinal stenosis, adjusted with an internal control for vertebral body size, and disability from lumbar stenosis. Materials and methods: one hundred and twenty-three consecutive patients with clinical and radiological confirmation of neural impingement secondary to lumbar stenosis were enrolled prospectively. Thecal sac anteroposterior (AP) diameter (TSD) and cross-sectional area (CSA), and vertebral body AP dimension (VBD) were determined. These parameters were then correlated with patients' symptoms using the modified Roland-Morris questionnaire (RMQ) disability score. Results: No statistically significant inverse correlation was found between the TSD and RMQ score (p = 0.433), between the CSA and RMQ score (p = 0.124), or between the TSD:VBD ratio and RMQ score (p = 0.109). There was a significant positive correlation between the CSA:VBD ratio and RMQ score (p = .036), and therefore, there was no statistical support for an inverse relationship between the two. There was a significant difference in mean RMQ scores when the patients were divided into those with CSA greater than or equal to 70 mm 2 and those less than 70 mm 2 , with T = -2.104 and p = 0.038. Conclusion: The degree of radiographic lumbar spinal stenosis, even with the use of an internal control of vertebral body size and standardized disability questionnaires, does not correlate with clinical symptoms. However, patients with more severe stenosis below a CSA critical threshold of 70 mm 2 , have significantly greater functional disability

  5. The Relationship of Body Size and Adiposity to Source of Self-Esteem in College Women

    Science.gov (United States)

    Moncur, Breckann; Bailey, Bruce W.; Lockhart, Barbara D.; LeCheminant, James D.; Perkins, Annette E.

    2013-01-01

    Background: Studies looking at self-esteem and body size or adiposity generally demonstrate a negative relationship. However, the relationship between the source of self-esteem and body size has not been examined in college women. Purpose: The purpose of this study was to evaluate the relationship of body size and adiposity to source of…

  6. Strength, body composition, and functional outcomes in the squat versus leg press exercises.

    Science.gov (United States)

    Rossi, Fabrício E; Schoenfeld, Brad J; Ocetnik, Skyler; Young, Jonathan; Vigotsky, Andrew; Contreras, Bret; Krieger, James W; Miller, Michael G; Cholewa, Jason

    2018-03-01

    The purpose of this study was to compare strength, body composition, and functional outcome measures following performance of the back squat, leg press, or a combination of the two exercises. Subjects were pair-matched based on initial strength levels and then randomly assigned to 1 of 3 groups: a squat-only group (SQ) that solely performed squats for the lower body; a leg press-only group (LP) that solely performed leg presses for the lower body, or a combined squat and leg press group (SQ-LP) that performed both squats and leg presses for the lower body. All other RT variables were held constant. The study period lasted 10 weeks with subjects performing 2 lower body workouts per week comprising 6 sets per session at loads corresponding to 8-12 RM with 90- to 120-second rest intervals. Results showed that SQ had greater transfer to maximal squat strength compared to the leg press. Effect sizes favored SQ and SQ-LP versus LP with respect to countermovement jump while greater effect sizes for dynamic balance were noted for SQ-LP and LP compared to SQ, although no statistical differences were noted between conditions. These findings suggest that both free weights and machines can improve functional outcomes, and that the extent of transfer may be specific to the given task.

  7. High prevalence of homing behaviour among juvenile coral-reef fishes and the role of body size

    Science.gov (United States)

    Streit, Robert P.; Bellwood, David R.

    2017-12-01

    Adult coral-reef fishes display a remarkable ability to return home after being displaced. However, we know very little about homing behaviour in juvenile fishes. Homing behaviour in juvenile fishes is of interest because it will shape subsequent spatial distributions of adult fish communities. Comparing multiple species, families and functional groups allows us to distinguish between species-specific traits and more generalised, species-independent traits that may drive homing behaviour. Using displacement experiments of up to 150 m, we quantified homing behaviour of juvenile, newly recruited reef fishes of seven species in three families, including herbivorous parrotfishes and rabbitfishes, carnivorous wrasse and planktivorous damselfishes. All species showed the ability to home successfully, but success rates differed among species. Juvenile parrotfishes were the most successful (67% returning home), while return rates in the other species ranged from 10.5% ( Siganus doliatus) to 28.9% ( Coris batuensis). However, across all species body size appeared to be the main driver of homing success, rather than species-specific traits. With every cm increase in body size, odds of returning home almost tripled (170% increase) across all species. Interestingly, the probability of getting lost was not related to body size, which suggests that mortality was not a major driver of unsuccessful homing. Homing probability halved beyond displacement distances of 10 m and then remained stable. Higher likelihood of homing over short distances may suggest that different sensory cues are used to navigate. Overall, our results suggest that homing ability is a widespread trait among juvenile reef fishes. A `sense of home' and site attachment appear to develop early during ontogeny, especially above taxon-specific size thresholds. Hence, spatial flexibility exists only in a brief window after settlement, with direct implications for subsequent patterns of connectivity and ecosystem

  8. Obesity Bias in Children: The Role of Actual and Perceived Body Size

    Science.gov (United States)

    Kornilaki, Ekaterina N.

    2015-01-01

    The aim of this study was to examine how children perceive their body size and whether their actual or perceived body size can explain their anti-fat views. Four hundred and fourteen 5-6, 7-8 and 9-10-year-old children were read short vignettes depicting two characters, one possessing a positive and the other a negative quality. Following each…

  9. The impact of psychological stress on men's judgements of female body size.

    Directory of Open Access Journals (Sweden)

    Viren Swami

    Full Text Available BACKGROUND: Previous work has suggested that the experience of psychological stress may influence physical attractiveness ideals, but most evidence in favour of this hypothesis remains archival. The objective of this study was to experimentally investigate the impact of stress on men's judgements of female body size. METHODS: Men were randomly assigned to either an experimental group, in which they took part in a task that heightened stress (experimental group, n = 41 or in which they did not take part in such a task (control group, n = 40. Both groups rated the attractiveness of female bodies varying in size from emaciated to obese, completed a measure of appetite sensation, and had their body mass indices (BMIs measured. RESULTS: Between-groups analyses showed that the experimental group was matched with the control group in terms of mean age, BMI, and appetite sensation. Further analyses showed that men in the experimental group rated a significantly heavier female body size as maximally attractive than the control group. Men in the experimental group also rated heavier female bodies as more attractive and idealised a wider range of female figures than did the control group. CONCLUSION: This study found that the experience of stress was associated with a preference among men for heavier female body sizes. These results indicate that human attractiveness judgements are sensitive to variations in local ecologies and reflect adaptive strategies for dealing with changing environmental conditions.

  10. Waif goodbye! Average-size female models promote positive body image and appeal to consumers.

    Science.gov (United States)

    Diedrichs, Phillippa C; Lee, Christina

    2011-10-01

    Despite consensus that exposure to media images of thin fashion models is associated with poor body image and disordered eating behaviours, few attempts have been made to enact change in the media. This study sought to investigate an effective alternative to current media imagery, by exploring the advertising effectiveness of average-size female fashion models, and their impact on the body image of both women and men. A sample of 171 women and 120 men were assigned to one of three advertisement conditions: no models, thin models and average-size models. Women and men rated average-size models as equally effective in advertisements as thin and no models. For women with average and high levels of internalisation of cultural beauty ideals, exposure to average-size female models was associated with a significantly more positive body image state in comparison to exposure to thin models and no models. For men reporting high levels of internalisation, exposure to average-size models was also associated with a more positive body image state in comparison to viewing thin models. These findings suggest that average-size female models can promote positive body image and appeal to consumers.

  11. Reduced body size and cub recruitment in polar bears associated with sea ice decline

    Science.gov (United States)

    Rode, Karyn D.; Amstrup, Steven C.; Regehr, Eric V.

    2010-01-01

    Rates of reproduction and survival are dependent upon adequate body size and condition of individuals. Declines in size and condition have provided early indicators of population decline in polar bears (Ursus maritimus) near the southern extreme of their range. We tested whether patterns in body size, condition, and cub recruitment of polar bears in the southern Beaufort Sea of Alaska were related to the availability of preferred sea ice habitats and whether these measures and habitat availability exhibited trends over time, between 1982 and 2006. The mean skull size and body length of all polar bears over three years of age declined over time, corresponding with long‐term declines in the spatial and temporal availability of sea ice habitat. Body size of young, growing bears declined over time and was smaller after years when sea ice availability was reduced. Reduced litter mass and numbers of yearlings per female following years with lower availability of optimal sea ice habitat, suggest reduced reproductive output and juvenile survival. These results, based on analysis of a long‐term data set, suggest that declining sea ice is associated with nutritional limitations that reduced body size and reproduction in this population.

  12. ZResponse to selection, heritability and genetic correlations between body weight and body size in Pacific white shrimp, Litopenaeus vannamei

    Science.gov (United States)

    Andriantahina, Farafidy; Liu, Xiaolin; Huang, Hao; Xiang, Jianhai

    2012-03-01

    To quantify the response to selection, heritability and genetic correlations between weight and size of Litopenaeus vannamei, the body weight (BW), total length (TL), body length (BL), first abdominal segment depth (FASD), third abdominal segment depth (TASD), first abdominal segment width (FASW), and partial carapace length (PCL) of 5-month-old parents and of offspnng were measured by calculating seven body measunngs of offspnng produced by a nested mating design. Seventeen half-sib families and 42 full-sib families of L. vannamei were produced using artificial fertilization from 2-4 dams by each sire, and measured at around five months post-metamorphosis. The results show that hentabilities among vanous traits were high: 0.515±0.030 for body weight and 0.394±0.030 for total length. After one generation of selection. the selection response was 10.70% for offspring growth. In the 5th month, the realized heritability for weight was 0.296 for the offspnng generation. Genetic correlations between body weight and body size were highly variable. The results indicate that external morphological parameters can be applied dunng breeder selection for enhancing the growth without sacrificing animals for determining the body size and breed ability; and selective breeding can be improved significantly, simultaneously with increased production.

  13. AN AGENT-BASED APPROACH TO MODELING MAMMALIAN EVOLUTION: HOW RESOURCE DISTRIBUTION AND PREDATION AFFECT BODY SIZE

    OpenAIRE

    ANNE KANDLER; JEROEN B. SMAERS

    2012-01-01

    Macro-evolutionary investigations into cross-scale patterns of body size variation have put many of the pieces of the evolutionary body size puzzle in place. To further tackle micro- and meso-scale process-based reasons underlying changes in body size, researchers compare natural populations across different habitat structures, assessing which habitat structures correspond to which changes in body size variation. The complex multi-scale dynamics underlying the effect of the external environme...

  14. Thermal phenotypic plasticity of body size in Drosophila ...

    Indian Academy of Sciences (India)

    ... body size in Drosophila melanogaster: sexual dimorphism and genetic correlations. Jean R. David, Amir Yassin, Jean-Claude Moreteau, Helene Legout and Brigitte Moreteau. J. Genet. 90, 295–302. Table 1. Correlations between wing and thorax length at the within (n = 420) and between line level (n = 30). Temperature.

  15. Proximate composition of Mystus bleekeri in relation to body size ...

    African Journals Online (AJOL)

    Proximate composition of small catfish, Mystus bleekeri, from Nala Daik, Sialkot, Pakistan was investigated and fluctuation in relation to body size and condition factor was carried out. Mean percentages for water, fat, protein and ash contents in the whole wet body weight of wild M. bleekeri were 77.87, 3.26, 15.01 and ...

  16. Canalization of body size matters for lifetime reproductive success of male predatory mites (Acari: Phytoseiidae).

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2014-04-01

    The adaptive canalization hypothesis predicts that highly fitness-relevant traits are canalized via past selection, resulting in low phenotypic plasticity and high robustness to environmental stress. Accordingly, we hypothesized that the level of phenotypic plasticity of male body size of the predatory mites Phytoseiulus persimilis (low plasticity) and Neoseiulus californicus (high plasticity) reflects the effects of body size variation on fitness, especially male lifetime reproductive success (LRS). We first generated small and standard-sized males of P. persimilis and N. californicus by rearing them to adulthood under limited and ample prey supply, respectively. Then, adult small and standard-sized males were provided with surplus virgin females throughout life to assess their mating and reproductive traits. Small male body size did not affect male longevity or the number of fertilized females but reduced male LRS of P. persimilis but not N. californicus . Proximately, the lower LRS of small than standard-sized P. persimilis males correlated with shorter mating durations, probably decreasing the amount of transferred sperm. Ultimately, we suggest that male body size is more strongly canalized in P. persimilis than N. californicus because deviation from standard body size has larger detrimental fitness effects in P. persimilis than N. californicus .

  17. Body size and predatory performance in wolves: Is bigger better?

    Science.gov (United States)

    MacNulty, D.R.; Smith, D.W.; Mech, L.D.; Eberly, L.E.

    2009-01-01

    Large body size hinders locomotor performance in ways that may lead to trade-offs in predator foraging ability that limit the net predatory benefit of larger size. For example, size-related improvements in handling prey may come at the expense of pursuing prey and thus negate any enhancement in overall predatory performance due to increasing size. 2. This hypothesis was tested with longitudinal data from repeated observations of 94 individually known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park, USA. Wolf size was estimated from an individually based sex-specific growth model derived from body mass measurements of 304 wolves. 3. Larger size granted individual wolves a net predatory advantage despite substantial variation in its effect on the performance of different predatory tasks; larger size improved performance of a strength-related task (grappling and subduing elk) but failed to improve performance of a locomotor-related task (selecting an elk from a group) for wolves > 39 kg. 4. Sexual dimorphism in wolf size also explained why males outperformed females in each of the three tasks considered (attacking, selecting, and killing). 5. These findings support the generalization that bigger predators are overall better hunters, but they also indicate that increasing size ultimately limits elements of predatory behaviour that require superior locomotor performance. We argue that this could potentially narrow the dietary niche of larger carnivores as well as limit the evolution of larger size if prey are substantially more difficult to pursue than to handle. ?? 2009 British Ecological Society.

  18. Body Size Estimation from Early to Middle Childhood: Stability of Underestimation, BMI, and Gender Effects

    Directory of Open Access Journals (Sweden)

    Silje Steinsbekk

    2017-11-01

    Full Text Available Individuals who are overweight are more likely to underestimate their body size than those who are normal weight, and overweight underestimators are less likely to engage in weight loss efforts. Underestimation of body size might represent a barrier to prevention and treatment of overweight; thus insight in how underestimation of body size develops and tracks through the childhood years is needed. The aim of the present study was therefore to examine stability in children’s underestimation of body size, exploring predictors of underestimation over time. The prospective path from underestimation to BMI was also tested. In a Norwegian cohort of 6 year olds, followed up at ages 8 and 10 (analysis sample: n = 793 body size estimation was captured by the Children’s Body Image Scale, height and weight were measured and BMI calculated. Overall, children were more likely to underestimate than overestimate their body size. Individual stability in underestimation was modest, but significant. Higher BMI predicted future underestimation, even when previous underestimation was adjusted for, but there was no evidence for the opposite direction of influence. Boys were more likely than girls to underestimate their body size at ages 8 and 10 (age 8: 38.0% vs. 24.1%; Age 10: 57.9% vs. 30.8% and showed a steeper increase in underestimation with age compared to girls. In conclusion, the majority of 6, 8, and 10-year olds correctly estimate their body size (prevalence ranging from 40 to 70% depending on age and gender, although a substantial portion perceived themselves to be thinner than they actually were. Higher BMI forecasted future underestimation, but underestimation did not increase the risk for excessive weight gain in middle childhood.

  19. Associations among body size across the life course, adult height and endometriosis.

    Science.gov (United States)

    Farland, L V; Missmer, S A; Bijon, A; Gusto, G; Gelot, A; Clavel-Chapelon, F; Mesrine, S; Boutron-Ruault, M C; Kvaskoff, M

    2017-08-01

    Are body size across the life course and adult height associated with endometriosis? Endometriosis is associated with lean body size during childhood, adolescence and adulthood; tall total adult height; and tall sitting height. The literature suggests that both adult body size and height are associated with endometriosis risk, but few studies have investigated the role of body size across the life course. Additionally, no study has investigated the relationships between components of height and endometriosis. We used a nested case-control design within E3N (Etude Epidémiologique auprès de femmes de l'Education Nationale), a prospective cohort of French women. Data were updated every 2-3 years through self-administered questionnaires. Odds ratios (ORs) and 95% CIs were computed using logistic regression models adjusted for a priori confounding factors. A total of 2416 endometriosis cases were reported as surgically ascertained among the 61 208 included women. The odds of endometriosis were lower among women who reported having a large versus lean body size at 8 years (P for trend = 0.003), at menarche (P for trend endometriosis compared to those in the lowest (endometriosis. Endometriosis cases may be prone to misclassification; however, we restricted our case definition to surgically-confirmed cases, which showed a high validation rate. Body size is based on retrospective self-report, which may be subject to recall bias. The results of this study suggest that endometriosis is positively associated with lean body size across the life course and total adult height. They also suggest that components of height are associated with endometriosis, which should be investigated further. The Mutuelle Générale de l'Education Nationale (MGEN); the European Community; the French League against Cancer (LNCC); Gustave Roussy; the French Institute of Health and Medical Research (Inserm). L.V.F. was supported by a T32 grant (#HD060454) in reproductive, perinatal and pediatric

  20. Breaking Haller's rule: brain-body size isometry in a minute parasitic wasp.

    NARCIS (Netherlands)

    Woude, van der E.; Smid, H.M.; Chittka, L.; Huigens, M.E.

    2013-01-01

    Throughout the animal kingdom, Haller's rule holds that smaller individuals have larger brains relative to their body than larger-bodied individuals. Such brain-body size allometry is documented for all animals studied to date, ranging from small ants to the largest mammals. However, through

  1. Body Size as a Driver of Scavenging in Theropod Dinosaurs.

    Science.gov (United States)

    Kane, Adam; Healy, Kevin; Ruxton, Graeme D; Jackson, Andrew L

    2016-06-01

    Theropod dinosaurs dominated Earth's terrestrial ecosystem as a diverse group of predators for more than 160 million years, yet little is known about their foraging ecology. Maintaining a balanced energy budget presented a major challenge for therapods, which ranged from the chicken-sized Microraptor up to the whale-sized Giganotosaurus, in the face of intense competition and the demands of ontogenetic growth. Facultative scavenging, a behavior present in almost all modern predators, may have been important in supplementing energetically expensive lifestyles. By using agent-based models based on the allometric relationship between size and foraging behaviors, we show that theropods between 27 and 1,044 kg would have gained a significant energetic advantage over individuals at both the small and large extremes of theropod body mass through their scavenging efficiency. These results were robust to rate of competition, primary productivity, and detection distance. Our models demonstrate the potential importance of facultative scavenging in theropods and the role of body size in defining its prevalence in Mesozoic terrestrial systems.

  2. Correlation between Leukocyte Numbers and Body Size of Rainbow Trout

    DEFF Research Database (Denmark)

    Mohammad, Rezkar Jaafar; Otani, Maki; Kania, Per Walter

    2016-01-01

    wild and cultured fish and we show that the size of the leukocyte population increases exponentially with body size of rainbow trout. Four groups (5 fish/group) of naive rainbow trout (Oncorhynchus mykiss) with a mean body weight of 2 - 4 g (group I), 4 - 6 g (group II), 25 - 30 g (group III), and 650...... towards an antigen to be initiated even in fry. The number of leukocytes in individual fish at different developmental stages is likely to influence the capacity of the fish to respond simultaneously to several antigens (pathogens and vaccine components). This parameter may therefore be crucial for both...... - 780 g (group IV) were investigated. The number of lymphocytes was generally higher in head kidney compared to blood and spleen but they dominated in all samples (blood, head kidney and spleen) and their numbers increased exponentially with fish size. Percentages of lymphocytes in relation...

  3. Women Build Long Bones With Less Cortical Mass Relative to Body Size and Bone Size Compared With Men.

    Science.gov (United States)

    Jepsen, Karl J; Bigelow, Erin M R; Schlecht, Stephen H

    2015-08-01

    The twofold greater lifetime risk of fracturing a bone for white women compared with white men and black women has been attributed in part to differences in how the skeletal system accumulates bone mass during growth. On average, women build more slender long bones with less cortical area compared with men. Although slender bones are known to have a naturally lower cortical area compared with wider bones, it remains unclear whether the relatively lower cortical area of women is consistent with their increased slenderness or is reduced beyond that expected for the sex-specific differences in bone size and body size. Whether this sexual dimorphism is consistent with ethnic background and is recapitulated in the widely used mouse model also remains unclear. We asked (1) do black women build bones with reduced cortical area compared with black men; (2) do white women build bones with reduced cortical area compared with white men; and (3) do female mice build bones with reduced cortical area compared with male mice? Bone strength and cross-sectional morphology of adult human and mouse bone were calculated from quantitative CT images of the femoral midshaft. The data were tested for normality and regression analyses were used to test for differences in cortical area between men and women after adjusting for body size and bone size by general linear model (GLM). Linear regression analysis showed that the femurs of black women had 11% lower cortical area compared with those of black men after adjusting for body size and bone size (women: mean=357.7 mm2; 95% confidence interval [CI], 347.9-367.5 mm2; men: mean=400.1 mm2; 95% CI, 391.5-408.7 mm2; effect size=1.2; pbone size (women: mean=350.1 mm2; 95% CI, 340.4-359.8 mm2; men: mean=394.3 mm2; 95% CI, 386.5-402.1 mm2; effect size=1.3; pbone size (female: mean=0.73 mm2; 95% CI, 0.71-0.74 mm2; male: mean=0.70 mm2; 95% CI, 0.68-0.71 mm2; effect size=0.74; p=0.04, GLM). Female femurs are not simply a more slender version of male

  4. Body Size Adaptations to Altitudinal Climatic Variation in Neotropical Grasshoppers of the Genus Sphenarium (Orthoptera: Pyrgomorphidae)

    Science.gov (United States)

    2015-01-01

    Altitudinal clines in body size can result from the effects of natural and sexual selection on growth rates and developing times in seasonal environments. Short growing and reproductive seasons constrain the body size that adults can attain and their reproductive success. Little is known about the effects of altitudinal climatic variation on the diversification of Neotropical insects. In central Mexico, in addition to altitude, highly heterogeneous topography generates diverse climates that can occur even at the same latitude. Altitudinal variation and heterogeneous topography open an opportunity to test the relative impact of climatic variation on body size adaptations. In this study, we investigated the relationship between altitudinal climatic variation and body size, and the divergence rates of sexual size dimorphism (SSD) in Neotropical grasshoppers of the genus Sphenarium using a phylogenetic comparative approach. In order to distinguish the relative impact of natural and sexual selection on the diversification of the group, we also tracked the altitudinal distribution of the species and trends of both body size and SSD on the phylogeny of Sphenarium. The correlative evidence suggests no relationship between altitude and body size. However, larger species were associated with places having a warmer winter season in which the temporal window for development and reproduction can be longer. Nonetheless, the largest species were also associated with highly seasonal environments. Moreover, large body size and high levels of SSD have evolved independently several times throughout the history of the group and male body size has experienced a greater evolutionary divergence than females. These lines of evidence suggest that natural selection, associated with seasonality and sexual selection, on maturation time and body size could have enhanced the diversification of this insect group. PMID:26684616

  5. Attention biases in preoccupation with body image: An ERP study of the role of social comparison and automaticity when processing body size.

    Science.gov (United States)

    Uusberg, Helen; Peet, Krista; Uusberg, Andero; Akkermann, Kirsti

    2018-03-17

    Appearance-related attention biases are thought to contribute to body image disturbances. We investigated how preoccupation with body image is associated with attention biases to body size, focusing on the role of social comparison processes and automaticity. Thirty-six women varying on self-reported preoccupation compared their actual body size to size-modified images of either themselves or a figure-matched peer. Amplification of earlier (N170, P2) and later (P3, LPP) ERP components recorded under low vs. high concurrent working memory load were analyzed. Women with high preoccupation exhibited an earlier bias to larger bodies of both self and peer. During later processing stages, they exhibited a stronger bias to enlarged as well as reduced self-images and a lack of sensitivity to size-modifications of the peer-image. Working memory load did not affect these biases systematically. Current findings suggest that preoccupation with body image involves an earlier attention bias to weight increase cues and later over-engagement with own figure. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Dissociating object-based from egocentric transformations in mental body rotation: effect of stimuli size.

    Science.gov (United States)

    Habacha, Hamdi; Moreau, David; Jarraya, Mohamed; Lejeune-Poutrain, Laure; Molinaro, Corinne

    2018-01-01

    The effect of stimuli size on the mental rotation of abstract objects has been extensively investigated, yet its effect on the mental rotation of bodily stimuli remains largely unexplored. Depending on the experimental design, mentally rotating bodily stimuli can elicit object-based transformations, relying mainly on visual processes, or egocentric transformations, which typically involve embodied motor processes. The present study included two mental body rotation tasks requiring either a same-different or a laterality judgment, designed to elicit object-based or egocentric transformations, respectively. Our findings revealed shorter response times for large-sized stimuli than for small-sized stimuli only for greater angular disparities, suggesting that the more unfamiliar the orientations of the bodily stimuli, the more stimuli size affected mental processing. Importantly, when comparing size transformation times, results revealed different patterns of size transformation times as a function of angular disparity between object-based and egocentric transformations. This indicates that mental size transformation and mental rotation proceed differently depending on the mental rotation strategy used. These findings are discussed with respect to the different spatial manipulations involved during object-based and egocentric transformations.

  7. Interactive effects of body-size structure and adaptive foraging on food-web stability.

    Science.gov (United States)

    Heckmann, Lotta; Drossel, Barbara; Brose, Ulrich; Guill, Christian

    2012-03-01

    Body-size structure of food webs and adaptive foraging of consumers are two of the dominant concepts of our understanding how natural ecosystems maintain their stability and diversity. The interplay of these two processes, however, is a critically important yet unresolved issue. To fill this gap in our knowledge of ecosystem stability, we investigate dynamic random and niche model food webs to evaluate the proportion of persistent species. We show that stronger body-size structures and faster adaptation stabilise these food webs. Body-size structures yield stabilising configurations of interaction strength distributions across food webs, and adaptive foraging emphasises links to resources closer to the base. Moreover, both mechanisms combined have a cumulative effect. Most importantly, unstructured random webs evolve via adaptive foraging into stable size-structured food webs. This offers a mechanistic explanation of how size structure adaptively emerges in complex food webs, thus building a novel bridge between these two important stabilising mechanisms. © 2012 Blackwell Publishing Ltd/CNRS.

  8. Vocal tract length and formant frequency dispersion correlate with body size in rhesus macaques.

    Science.gov (United States)

    Fitch, W T

    1997-08-01

    Body weight, length, and vocal tract length were measured for 23 rhesus macaques (Macaca mulatta) of various sizes using radiographs and computer graphic techniques. linear predictive coding analysis of tape-recorded threat vocalizations were used to determine vocal tract resonance frequencies ("formants") for the same animals. A new acoustic variable is proposed, "formant dispersion," which should theoretically depend upon vocal tract length. Formant dispersion is the averaged difference between successive formant frequencies, and was found to be closely tied to both vocal tract length and body size. Despite the common claim that voice fundamental frequency (F0) provides an acoustic indication of body size, repeated investigations have failed to support such a relationship in many vertebrate species including humans. Formant dispersion, unlike voice pitch, is proposed to be a reliable predictor of body size in macaques, and probably many other species.

  9. Relative Importance of Sex, Pre-Starvation Body Mass and Structural Body Size in the Determination of Exceptional Starvation Resistance of Anchomenus dorsalis (Coleoptera: Carabidae.

    Directory of Open Access Journals (Sweden)

    Michal Knapp

    Full Text Available In nature, almost all animals have to cope with periods of food shortage during their lifetimes. Starvation risks are especially high for carnivorous predatory species, which often experience long intervals between stochastic prey capturing events. A laboratory experiment using the common predatory carabid beetle Anchomenus dorsalis revealed an exceptional level of starvation resistance in this species: males survived up to 137 days and females up to 218 days without food at 20°C. Individual starvation resistance was strongly positively affected by pre-starvation body mass but only slightly by beetle structural body size per se. Females outperformed males even when the effect of gender was corrected for the effects of structural body size and pre-starvation body mass. The better performance of females compared to males and of beetles with higher relative pre-starvation body mass could be linked to higher fat content and lean dry mass before starvation, followed by a greater decrease in both during starvation. There was also a difference between the sexes in the extent of body mass changes both during ad libitum feeding and following starvation; the body masses of females fluctuated more compared to males. This study stresses the need to distinguish between body mass and structural body size when investigating the ecological and evolutionary consequences of body size. Investigation of the net effects of body size and sex is necessary to disentangle the causes of differences in individual performances in studies of species with significant sexual size dimorphism.

  10. Body size and growth in 0- to 4-year-old children and the relation to body size in primary school age

    NARCIS (Netherlands)

    Stocks, T.; Renders, C.M.; Bulk-Bunschoten, A.M.W.; Hirasing, R.A.; Buuren, S. van; Seidell, J.C.

    2011-01-01

    Excess weight in early life is believed to increase susceptibility to obesity, and in support of such theory, excess weight and fast weight gain in early childhood have been related to overweight later in life. The aim of this study was to review the literature on body size and growth in 0- to

  11. Body size and growth in 0- to 4-year-old children and the relation to body size in primary school age

    NARCIS (Netherlands)

    Stocks, T; Renders, C M; Bulk-Bunschoten, A.M.W.; HiraSing, R.A.; van Buuren, S.; Seidell, J C

    Excess weight in early life is believed to increase susceptibility to obesity, and in support of such theory, excess weight and fast weight gain in early childhood have been related to overweight later in life. The aim of this study was to review the literature on body size and growth in 0- to

  12. My 'Fat Girl Complex': a preliminary investigation of sexual health and body image in women of size.

    Science.gov (United States)

    Satinsky, Sonya; Dennis, Barbara; Reece, Michael; Sanders, Stephanie; Bardzell, Shaowen

    2013-01-01

    Women of size who inhabit non-normative bodies may have different experiences with body image and sexual health than women of average body size. In this exploratory study, we interviewed four women of size recruited from a larger mixed-methodological study of body image and sexuality. Each woman was interviewed twice on topics of body image, sexuality and sexual health. Reconstructive Horizon Analysis was used to analyse the content of the interviews. Women who expressed that their bodies had inherent personal and social value regardless of size did not articulate connections between body size and their sexual health. However, those women who looked externally for validation of their attractiveness struggled with acceptance of their sexuality and bodies and spoke of ways in which their body size and appearance hindered them from having the sexually healthy lives that they wanted. Findings highlight two important components of women's sexual health as participants related them to body image: the right to pleasure and the right to engage only in wanted sexual activity. Participants described how negative body attitudes affected both of these aspects of their sexual health. Interventions targeting weight-based stigma may offer a means of indirectly promoting sexual health and autonomy in women.

  13. Effects of seed predators of different body size on seed mortality in Bornean logged forest.

    Science.gov (United States)

    Hautier, Yann; Saner, Philippe; Philipson, Christopher; Bagchi, Robert; Ong, Robert C; Hector, Andy

    2010-07-19

    The Janzen-Connell hypothesis proposes that seed and seedling enemies play a major role in maintaining high levels of tree diversity in tropical forests. However, human disturbance may alter guilds of seed predators including their body size distribution. These changes have the potential to affect seedling survival in logged forest and may alter forest composition and diversity. We manipulated seed density in plots beneath con- and heterospecific adult trees within a logged forest and excluded vertebrate predators of different body sizes using cages. We show that small and large-bodied predators differed in their effect on con- and heterospecific seedling mortality. In combination small and large-bodied predators dramatically decreased both con- and heterospecific seedling survival. In contrast, when larger-bodied predators were excluded small-bodied predators reduced conspecific seed survival leaving seeds coming from the distant tree of a different species. Our results suggest that seed survival is affected differently by vertebrate predators according to their body size. Therefore, changes in the body size structure of the seed predator community in logged forests may change patterns of seed mortality and potentially affect recruitment and community composition.

  14. Body Size Perceptions and Weight Status of Adults in a Nigerian ...

    African Journals Online (AJOL)

    Subjects and Methods: A cross‑sectional sample of 183 adults living in a rural community, South‑West Nigeria was randomly recruited into the study. Their verbal and visual body size perceptions were assessed through structured questions and body images. Descriptive and inferential statistics were used to analyze the ...

  15. Understanding mismatches in body size, speed and power among adolescent rugby union players.

    Science.gov (United States)

    Krause, Lyndon M; Naughton, Geraldine A; Denny, Greg; Patton, Declan; Hartwig, Tim; Gabbett, Tim J

    2015-05-01

    With adolescent sport increasingly challenged by mismatches in size, new strategies are important to maximize participation. The objectives were to (1) improve the understanding of mismatches in physical size, speed and power in adolescent rugby union players, (2) explore associations between size and performance with demographic, playing-history, and injury profiles, and (3) explore the applicability of existing criteria for age/body mass-based dispensation (playing-down) strategies. Cross-sectional study. Four hundred and eighty-five male community rugby union players were recruited from three Australian states selected to represent community-based U12, U13, U14 and U15 players. Body mass, stature, speed (10, 30, and 40 m sprints) and lower-leg power (relative peak power and relative peak force) were measured. Independent student t-tests, linear regressions and Chi square analyses were undertaken. Mean values in age groups for size, speed and power masked considerable overlap in the ranges within specific age groups of adolescent rugby players. Only a small proportion of players (approximately 5%) shared the highest and lowest tertiles for speed, relative peak power and body mass. Physical size was not related to injury. The mean body mass of current community rugby union players was above the 75th percentile on normative growth-charts. The notion that bigger, faster, and more powerful characteristics occur simultaneously in adolescent rugby players was not supported in the present study. Current practices in body mass-based criteria for playing down an age group lack a sufficient evidence for decision-making. Dispensation solely based on body mass may not address mismatch in junior rugby union. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  16. Body size and the timing of egg production in parasitoid wasps.

    NARCIS (Netherlands)

    Ellers, J.; Jervis, M.

    2003-01-01

    In insects several key fitness-related variables are positively correlated with intraspecific variation in body size, but little is known about size-related variation in the timing of egg production within species. Female insects are known to vary in the degree to which they concentrate egg

  17. Body size evolution in an old insect order: No evidence for Cope's Rule in spite of fitness benefits of large size.

    Science.gov (United States)

    Waller, John T; Svensson, Erik I

    2017-09-01

    We integrate field data and phylogenetic comparative analyses to investigate causes of body size evolution and stasis in an old insect order: odonates ("dragonflies and damselflies"). Fossil evidence for "Cope's Rule" in odonates is weak or nonexistent since the last major extinction event 65 million years ago, yet selection studies show consistent positive selection for increased body size among adults. In particular, we find that large males in natural populations of the banded demoiselle (Calopteryx splendens) over several generations have consistent fitness benefits both in terms of survival and mating success. Additionally, there was no evidence for stabilizing or conflicting selection between fitness components within the adult life-stage. This lack of stabilizing selection during the adult life-stage was independently supported by a literature survey on different male and female fitness components from several odonate species. We did detect several significant body size shifts among extant taxa using comparative methods and a large new molecular phylogeny for odonates. We suggest that the lack of Cope's rule in odonates results from conflicting selection between fitness advantages of large adult size and costs of long larval development. We also discuss competing explanations for body size stasis in this insect group. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  18. Mammal body size evolution in North America and Europe over 20 Myr: similar trends generated by different processes.

    Science.gov (United States)

    Huang, Shan; Eronen, Jussi T; Janis, Christine M; Saarinen, Juha J; Silvestro, Daniele; Fritz, Susanne A

    2017-02-22

    Because body size interacts with many fundamental biological properties of a species, body size evolution can be an essential component of the generation and maintenance of biodiversity. Here we investigate how body size evolution can be linked to the clade-specific diversification dynamics in different geographical regions. We analyse an extensive body size dataset of Neogene large herbivores (covering approx. 50% of the 970 species in the orders Artiodactyla and Perissodactyla) in Europe and North America in a Bayesian framework. We reconstruct the temporal patterns of body size in each order on each continent independently, and find significant increases of minimum size in three of the continental assemblages (except European perissodactyls), suggesting an active selection for larger bodies. Assessment of trait-correlated birth-death models indicates that the common trend of body size increase is generated by different processes in different clades and regions. Larger-bodied artiodactyl species on both continents tend to have higher origination rates, and both clades in North America show strong links between large bodies and low extinction rate. Collectively, our results suggest a strong role of species selection and perhaps of higher-taxon sorting in driving body size evolution, and highlight the value of investigating evolutionary processes in a biogeographic context. © 2017 The Author(s).

  19. Carotid body size measured by computed tomographic angiography in individuals born prematurely.

    Science.gov (United States)

    Bates, Melissa L; Welch, Brian T; Randall, Jess T; Petersen-Jones, Humphrey G; Limberg, Jacqueline K

    2018-05-24

    We tested the hypothesis that the carotid bodies would be smaller in individuals born prematurely or exposed to perinatal oxygen therapy when compared individuals born full term that did not receive oxygen therapy. A retrospective chart review was conducted on patients who underwent head/neck computed tomography angiography (CTA) at the Mayo Clinic between 10 and 40 years of age (n = 2503). Patients were identified as premature ( body images captured during the CTA were performed. Carotid body visualization was possible in 43% of patients and 52% of age, sex, and body mass index (BMI)-matched controls but only 17% of juvenile preterm subjects (p = 0.07). Of the carotid bodies that could be visualized, widest axial measurements of the carotid bodies in individuals born prematurely (n = 7, 34 ± 4 weeks gestation, birth weight: 2460 ± 454 g; average size: 2.5 ± 0.2 cm) or individuals exposed to perinatal oxygen therapy (n = 3, 38 ± 2 weeks gestation, Average size: 2.2 ± 0.1 cm) were not different when compared to controls (2.3 ± 0.2 cm and 2.3 ± 0.2 cm, respectively, p > 0.05). Carotid body size, as measured using CTA, is not smaller in adults born prematurely or exposed to perinatal oxygen therapy when compared to sex, age, and BMI-matched controls. However, carotid body visualization was lower in juvenile premature patients. The decreased ability to visualize the carotid bodies in these individuals may be a result of their prematurity. Copyright © 2018. Published by Elsevier B.V.

  20. Habitat structure and body size distributions: Cross-ecosystem comparison for taxa with determinate and indeterminate growth

    Science.gov (United States)

    Nash, Kirsty L.; Allen, Craig R.; Barichievy, Chris; Nystrom, Magnus; Sundstrom, Shana M.; Graham, Nicholas A.J.

    2014-01-01

    Habitat structure across multiple spatial and temporal scales has been proposed as a key driver of body size distributions for associated communities. Thus, understanding the relationship between habitat and body size is fundamental to developing predictions regarding the influence of habitat change on animal communities. Much of the work assessing the relationship between habitat structure and body size distributions has focused on terrestrial taxa with determinate growth, and has primarily analysed discontinuities (gaps) in the distribution of species mean sizes (species size relationships or SSRs). The suitability of this approach for taxa with indeterminate growth has yet to be determined. We provide a cross-ecosystem comparison of bird (determinate growth) and fish (indeterminate growth) body mass distributions using four independent data sets. We evaluate three size distribution indices: SSRs, species size–density relationships (SSDRs) and individual size–density relationships (ISDRs), and two types of analysis: looking for either discontinuities or abundance patterns and multi-modality in the distributions. To assess the respective suitability of these three indices and two analytical approaches for understanding habitat–size relationships in different ecosystems, we compare their ability to differentiate bird or fish communities found within contrasting habitat conditions. All three indices of body size distribution are useful for examining the relationship between cross-scale patterns of habitat structure and size for species with determinate growth, such as birds. In contrast, for species with indeterminate growth such as fish, the relationship between habitat structure and body size may be masked when using mean summary metrics, and thus individual-level data (ISDRs) are more useful. Furthermore, ISDRs, which have traditionally been used to study aquatic systems, present a potentially useful common currency for comparing body size distributions

  1. Effect of body size and temperature on respiration of Galaxias maculatus (Pisces: Galaxiidae)

    Science.gov (United States)

    Milano, D.; Vigliano, P.H.; Beauchamp, David A.

    2017-01-01

    Body mass and temperature are primary determinants of metabolic rate in ectothermic animals. Oxygen consumption of post-larval Galaxias maculatus was measured in respirometry trials under different temperatures (5–21°C) and varying body masses (0.1–>1.5 g) spanning a relevant range of thermal conditions and sizes. Specific respiration rates (R in g O2 g−1 d−1) declined as a power function of body mass and increased exponentially with temperature and was expressed as: R = 0.0007 * W −0.31 * e 0.13 * T. The ability of this model to predict specific respiration rate was evaluated by comparing observed values with those predicted by the model. Our findings suggest that the respiration rate of G. maculatus is the result of multiple interactive processes (intrinsic and extrinsic factors) that modulate each other in ‘meta-mechanistic’ ways; this would help to explain the species’ ability to undergo the complex ontogenetic habitat shifts observed in the lakes of the Andean Patagonic range.

  2. Body size and symbiotic status influence gonad development in Aiptasia pallida anemones.

    Science.gov (United States)

    Carlisle, Judith F; Murphy, Grant K; Roark, Alison M

    2017-01-01

    Pale anemones ( Aiptasia pallida ) coexist with dinoflagellates (primarily Symbiodinium minutum ) in a mutualistic relationship. The purpose of this study was to investigate the role of these symbionts in gonad development of anemone hosts. Symbiotic and aposymbiotic anemones were subjected to light cycles that induced gametogenesis. These anemones were then sampled weekly for nine weeks, and gonad development was analyzed histologically. Anemone size was measured as mean body column diameter, and oocytes or sperm follicles were counted for each anemone. Generalized linear models were used to evaluate the influence of body size and symbiotic status on whether gonads were present and on the number of oocytes or sperm follicles produced. Body size predicted whether gonads were present, with larger anemones being more likely than smaller anemones to develop gonads. Both body size and symbiotic status predicted gonad size, such that larger and symbiotic anemones produced more oocytes and sperm follicles than smaller and aposymbiotic anemones. Overall, only 22 % of aposymbiotic females produced oocytes, whereas 63 % of symbiotic females produced oocytes. Similarly, 6 % of aposymbiotic males produced sperm follicles, whereas 60 % of symbiotic males produced sperm follicles. Thus, while gonads were present in 62 % of symbiotic anemones, they were present in only 11 % of aposymbiotic anemones. These results indicate that dinoflagellate symbionts influence gonad development and thus sexual maturation in both female and male Aiptasia pallida anemones. This finding substantiates and expands our current understanding of the importance of symbionts in the development and physiology of cnidarian hosts.

  3. Beauty, body size and wages: Evidence from a unique data set.

    Science.gov (United States)

    Oreffice, Sonia; Quintana-Domeque, Climent

    2016-09-01

    We analyze how attractiveness rated at the start of the interview in the German General Social Survey is related to weight, height, and body mass index (BMI), separately by gender and accounting for interviewers' characteristics or fixed effects. We show that height, weight, and BMI all strongly contribute to male and female attractiveness when attractiveness is rated by opposite-sex interviewers, and that anthropometric characteristics are irrelevant to male interviewers when assessing male attractiveness. We also estimate whether, controlling for beauty, body size measures are related to hourly wages. We find that anthropometric attributes play a significant role in wage regressions in addition to attractiveness, showing that body size cannot be dismissed as a simple component of beauty. Our findings are robust to controlling for health status and accounting for selection into working. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Body size and premolar evolution in the early-middle eocene euprimates of Wyoming.

    Science.gov (United States)

    Jones, Katrina E; Rose, Kenneth D; Perry, Jonathan M G

    2014-01-01

    The earliest euprimates to arrive in North America were larger-bodied notharctids and smaller-bodied omomyids. Through the Eocene, notharctids generally continued to increase in body size, whereas omomyids generally radiated within small- and increasingly mid-sized niches in the middle Eocene. This study examines the influence of changing body size and diet on the evolution of the lower fourth premolar in Eocene euprimates. The P4 displays considerable morphological variability in these taxa. Despite the fact that most studies of primate dental morphology have focused on the molars, P4 can also provide important paleoecological insights. We analyzed the P4 from 177 euprimate specimens, representing 35 species (11 notharctids and 24 omomyids), in three time bins of approximately equal duration: early Wasatchian, late Wasatchian, and Bridgerian. Two-dimensional surface landmarks were collected from lingual photographs, capturing important variation in cusp position and tooth shape. Disparity metrics were calculated and compared for the three time bins. In the early Eocene, notharctids have a more molarized P4 than omomyids. During the Bridgerian, expanding body size range of omomyids was accompanied by a significant increase in P4 disparity and convergent evolution of the semimolariform condition in the largest omomyines. P4 morphology relates to diet in early euprimates, although patterns vary between families. Copyright © 2013 Wiley Periodicals, Inc.

  5. Factors determining the average body size of geographically separated Arctodiaptomus salinus (Daday, 1885) populations

    OpenAIRE

    Anufriieva, Elena V.; Shadrin, Nickolai V.

    2014-01-01

    Arctodiaptomus salinus inhabits water bodies across Eurasia and North Africa. Based on our own data and that from the literature, we analyzed the influences of several factors on the intra- and inter-population variability of this species. A strong negative linear correlation between temperature and average body size in the Crimean and African populations was found, in which the parameters might be influenced by salinity. Meanwhile, asignificant negative correlation between female body size a...

  6. Body Size of Male Youth Soccer Players: 1978-2015.

    Science.gov (United States)

    Malina, Robert M; Figueiredo, António J; Coelho-E-Silva, Manuel J

    2017-10-01

    Studies of the body size and proportions of athletes have a long history. Comparisons of athletes within specific sports across time, though not extensive, indicate both positive and negative trends. To evaluate secular variation in heights and weights of male youth soccer players reported in studies between 1978 and 2015. Reported mean ages, heights, and weights of male soccer players 9-18 years of age were extracted from the literature and grouped into two intervals: 1978-99 and 2000-15. A third-order polynomial was fitted to the mean heights and weights across the age range for each interval, while the Preece-Baines model 1 was fitted to the grand means of mean heights and mean weights within each chronological year to estimate ages at peak height velocity and peak weight velocity for each time interval. Third-order polynomials applied to all data points and estimates based on the Preece-Baines model applied to grand means for each age group provided similar fits. Both indicated secular changes in body size between the two intervals. Secular increases in height and weight between 1978-99 and 2000-15 were especially apparent between 13 and 16 years of age, but estimated ages at peak height velocity (13.01 and 12.91 years) and peak weight velocity (13.86 and 13.77 years) did not differ between the time intervals. Although the body size of youth soccer players increased between 1978-99 and 2000-15, estimated ages at peak height velocity and peak weight velocity did not change. The increase in height and weight likely reflected improved health and nutritional conditions, in addition to the selectivity of soccer reflected in systematic selection and retention of players advanced in maturity status, and exclusion of late maturing players beginning at about 12-13 years of age. Enhanced training programs aimed at the development of strength and power are probably an additional factor contributing to secular increases in body weight.

  7. Are rates of species diversification and body size evolution coupled in the ferns?

    Science.gov (United States)

    Testo, Weston L; Sundue, Michael A

    2018-03-01

    Understanding the relationship between phenotypic evolution and lineage diversification is a central goal of evolutionary biology. To extend our understanding of the role morphological evolution plays in the diversification of plants, we examined the relationship between leaf size evolution and lineage diversification across ferns. We tested for an association between body size evolution and lineage diversification using a comparative phylogenetic approach that combined a time-calibrated phylogeny and leaf size data set for 2654 fern species. Rates of leaf size change and lineage diversification were estimated using BAMM, and rate correlations were performed for rates obtained for all families and individual species. Rates and patterns of rate-rate correlation were also analyzed separately for terrestrial and epiphytic taxa. We find no significant correlation between rates of leaf area change and lineage diversification, nor was there a difference in this pattern when growth habit is considered. Our results are consistent with the findings of an earlier study that reported decoupled rates of body size evolution and diversification in the Polypodiaceae, but conflict with a recent study that reported a positive correlation between body size evolution and lineage diversification rates in the tree fern family Cyatheaceae. Our findings indicate that lineage diversification in ferns is largely decoupled from shifts in body size, in contrast to several other groups of organisms. Speciation in ferns appears to be primarily driven by hybridization and isolation along elevational gradients, rather than adaptive radiations featuring prominent morphological restructuring. The exceptional diversity of leaf morphologies in ferns appears to reflect a combination of ecophysiological constraints and adaptations that are not key innovations. © 2018 Botanical Society of America.

  8. Life course evolution of body size and breast cancer survival in the E3N cohort.

    Science.gov (United States)

    His, Mathilde; Le Guélennec, Marine; Mesrine, Sylvie; Boutron-Ruault, Marie-Christine; Clavel-Chapelon, Françoise; Fagherazzi, Guy; Dossus, Laure

    2018-04-15

    Although adult obesity has been associated with poor breast cancer survival, data on adiposity at different periods in life and its lifelong evolution are scarce. Our aims were to assess the associations between breast cancer survival and body size during childhood, puberty and early adulthood and body size trajectories from childhood to adulthood. Self-assessed body size at age 8, at puberty, at age 20-25 and at age 35-40 and trajectories of body size of 4,662 breast cancer survivors from the prospective E3N cohort were studied in relation to risk of death from any cause, death from breast cancer and second invasive cancer event using multivariate Cox regression models. Four trajectories of body size were identified (T1 "moderate increase," T2 "stable/low increase," T3 "increase at puberty" and T4 "constantly high"). Compared with stable body size, an increase in body size during adult life was associated with an increased risk of death from any cause (HR T1 vs. T2 = 1.27; 95% CI = 1.01-1.60) and an increased risk of second invasive cancer event (HR T1 vs. T2 = 1.25; 95% CI = 1.06-1.47). Silhouettes at various ages were not associated with survival. Our results suggest that the evolution of body size from childhood to adulthood has a long-term influence on breast cancer survival. Although these results need to be confirmed, this work sheds light on the need to combine lifelong approaches to current BMI to better identify breast cancer survivors who are at higher risk of recurrence or second primary cancer, or of death. © 2017 UICC.

  9. Body size and mating success in Drosophila willistoni are ...

    Indian Academy of Sciences (India)

    Mating activity and wing length were investigated in the F1 progeny of Drosophila willistoni females collected in the field to examine any possible relationship between body size and mating success. The flies were observed in a mating chamber under laboratory conditions. No significant differences in wing length were ...

  10. Variation of Body Size in Rice Water Weevil (Coleoptera: Curculionidae) and Its Associations with Population Biology

    OpenAIRE

    Huang, Yunshan; Ao, Yan; Jiang, Mingxing; Way, Michael O

    2018-01-01

    Abstract Life history characteristics help us to determine the ability of invasive species to establish and thrive in an exotic environment. However, so far, there have been very few reports concerning geographic variation in the body size of invasive insects and the associations between body size variation and population biology. In this study, we surveyed the geographic variation in body size of an invasive agricultural pest, the rice water weevil Lissorhoptrus oryzophilus Kuschel (Coleopte...

  11. The role of underestimating body size for self-esteem and self-efficacy among grade five children in Canada.

    Science.gov (United States)

    Maximova, Katerina; Khan, Mohammad K A; Austin, S Bryn; Kirk, Sara F L; Veugelers, Paul J

    2015-10-01

    Underestimating body size hinders healthy behavior modification needed to prevent obesity. However, initiatives to improve body size misperceptions may have detrimental consequences on self-esteem and self-efficacy. Using sex-specific multiple mixed-effect logistic regression models, we examined the association of underestimating versus accurate body size perceptions with self-esteem and self-efficacy in a provincially representative sample of 5075 grade five school children. Body size perceptions were defined as the standardized difference between the body mass index (BMI, from measured height and weight) and self-perceived body size (Stunkard body rating scale). Self-esteem and self-efficacy for physical activity and healthy eating were self-reported. Most of overweight boys and girls (91% and 83%); and most of obese boys and girls (93% and 90%) underestimated body size. Underestimating weight was associated with greater self-efficacy for physical activity and healthy eating among normal-weight children (odds ratio: 1.9 and 1.6 for boys, 1.5 and 1.4 for girls) and greater self-esteem among overweight and obese children (odds ratio: 2.0 and 6.2 for boys, 2.0 and 3.4 for girls). Results highlight the importance of developing optimal intervention strategies as part of targeted obesity prevention efforts that de-emphasize the focus on body weight, while improving body size perceptions. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Microgeographic body size variation in a high elevation Andean anole (Anolis mariarum; Squamata, Polychrotidae

    Directory of Open Access Journals (Sweden)

    Brian C Bock

    2009-12-01

    Full Text Available Intra-specific body size variation is common and often is assumed to be adaptive. Studies of body size variation among sites should include or consider environmental and ecological variables in their designs. Additionally, reciprocal transplant or common garden studies will support which variables are really contributing to the observed body size variation. This study analyzed the microgeographic body size variation in Anolis mariarum, a small lizard endemic to Antioquia, Colombia. Parameters such as body size, shape, and lepidosis variation were quantified in 217 adult A. mariarum, belonging to six populations separated by less than 80km. Results showed that significant body size variation was not related to differences among sites in mean annual temperature, but covaried with mean annual precipitation, with the largest individuals occurring in dryer sites. Mark-recapture data obtained from 115 individuals from both the wettest and dryest sites from October 2004 to April 2005 showed that growth rates were higher at the latter. Eight males from each site were captured at the end of the mark- recapture study and reared for two months under identical conditions in a common garden study. Individuals from both sites grew faster when reared in the laboratory with food provided ad libitum. Although growth rates of males from the two populations did not differ significantly in the laboratory, males from the dryest site still maintained a significantly larger asymptotic body size in their growth trajectories. Multivariate analyses also demonstrated that both males and females from the six populations differed in terms of body shape and lepidosis. However, only female body size was found to covary significantly with an environmental gradient (precipitation. A. mariarum does not conform to Bergmann’s rule, but the relationship found between mean body size and asympotic growth with mean annual precipitation at these sites needs further analysis

  13. Insights into bioassessment of marine pollution using body-size distinctness of planktonic ciliates based on a modified trait hierarchy.

    Science.gov (United States)

    Xu, Henglong; Jiang, Yong; Xu, Guangjian

    2016-06-15

    Based on a modified trait hierarchy of body-size units, the feasibility for bioassessment of water pollution using body-size distinctness of planktonic ciliates was studied in a semi-enclosed bay, northern China. An annual dataset was collected at five sampling stations within a gradient of heavy metal contaminants. Results showed that: (1) in terms of probability density, the body-size spectra of the ciliates represented significant differences among the five stations; (2) bootstrap average analysis demonstrated a spatial variation in body-size rank patterns in response to pollution stress due to heavy metals; and (3) the average body-size distinctness (Δz(+)) and variation in body-size distinctness (Λz(+)), based on the modified trait hierarchy, revealed a clear departure pattern from the expected body-size spectra in areas with pollutants. These results suggest that the body-size diversity measures based on the modified trait hierarchy of the ciliates may be used as a potential indicator of marine pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Diabetes Awareness and Body Size Perceptions of Cree Schoolchildren

    Science.gov (United States)

    Willows, Noreen D.; Marshall, Dru; Raine, Kim; Ridley, Denise C.

    2009-01-01

    Native American Indians and First Nations are predisposed to obesity and diabetes. A study was done to understand Cree schoolchildren's diabetes awareness and body size perceptions in two communities that had diabetes awareness-raising activities in the Province of Quebec, Canada. Children (N = 203) in grades 4-6 were classified into weight…

  15. A longitudinal study of the relationships between the Big Five personality traits and body size perception.

    Science.gov (United States)

    Hartmann, Christina; Siegrist, Michael

    2015-06-01

    The present study investigated the longitudinal development of body size perception in relation to different personality traits. A sample of Swiss adults (N=2905, 47% men), randomly selected from the telephone book, completed a questionnaire on two consecutive years (2012, 2013). Body size perception was assessed with the Contour Drawing Rating Scale and personality traits were assessed with a short version of the Big Five Inventory. Longitudinal analysis of change indicated that men and women scoring higher on conscientiousness perceived themselves as thinner one year later. In contrast, women scoring higher on neuroticism perceived their body size as larger one year later. No significant effect was observed for men scoring higher on neuroticism. These results were independent of weight changes, body mass index, age, and education. Our findings suggest that personality traits contribute to body size perception among adults. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. A macroevolutionary explanation for energy equivalence in the scaling of body size and population density.

    Science.gov (United States)

    Damuth, John

    2007-05-01

    Across a wide array of animal species, mean population densities decline with species body mass such that the rate of energy use of local populations is approximately independent of body size. This "energetic equivalence" is particularly evident when ecological population densities are plotted across several or more orders of magnitude in body mass and is supported by a considerable body of evidence. Nevertheless, interpretation of the data has remained controversial, largely because of the difficulty of explaining the origin and maintenance of such a size-abundance relationship in terms of purely ecological processes. Here I describe results of a simulation model suggesting that an extremely simple mechanism operating over evolutionary time can explain the major features of the empirical data. The model specifies only the size scaling of metabolism and a process where randomly chosen species evolve to take resource energy from other species. This process of energy exchange among particular species is distinct from a random walk of species abundances and creates a situation in which species populations using relatively low amounts of energy at any body size have an elevated extinction risk. Selective extinction of such species rapidly drives size-abundance allometry in faunas toward approximate energetic equivalence and maintains it there.

  17. Tradeoffs in the evolution of caste and body size in the hyperdiverse ant genus Pheidole.

    Directory of Open Access Journals (Sweden)

    Terrence P McGlynn

    Full Text Available The efficient investment of resources is often the route to ecological success, and the adaptability of resource investment may play a critical role in promoting biodiversity. The ants of the "hyperdiverse" genus Pheidole produce two discrete sterile castes, soldiers and minor workers. Within Pheidole, there is tremendous interspecific variation in proportion of soldiers. The causes and correlates of caste ratio variation among species of Pheidole remain enigmatic. Here we test whether a body size threshold model accounts for interspecific variation in caste ratio in Pheidole, such that species with larger body sizes produce relatively fewer soldiers within their colonies. We evaluated the caste ratio of 26 species of Pheidole and found that the body size of workers accounts for interspecific variation in the production of soldiers as we predicted. Twelve species sampled from one forest in Costa Rica yielded the same relationship as found in previously published data from many localities. We conclude that production of soldiers in the most species-rich group of ants is regulated by a body size threshold mechanism, and that the great variation in body size and caste ratio in Pheidole plays a role in niche divergence in this rapidly evolving taxon.

  18. Interdependent effects of male and female body size plasticity on mating behaviour of predatory mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2015-02-01

    The adaptive canalization hypothesis predicts that traits with low phenotypic plasticity are more fitness relevant, because they have been canalized via strong past selection, than traits with high phenotypic plasticity. Based on differing male body size plasticities of the predatory mites Phytoseiulus persimilis (low plasticity) and Neoseiulus californicus (high plasticity), we accordingly hypothesized that small male body size entails higher costs in female choice and male-male competition in P. persimilis than N. californicus . Males of both species are highly polygynous but females differ in the level of polyandry (low level in P. persimilis ; medium level in N. californicus ). We videotaped the mating interactions in triplets of either P. persimilis or N. californicus , consisting of a virgin female (small or standard-sized) and a small and a standard-sized male. Mating by both small and standard-sized P. persimilis females was biased towards standard-sized males, resulting from the interplay between female preference for standard-sized males and the inferiority of small males in male-male competition. In contrast, mating by N. californicus females was equally balanced between small and standard-sized males. Small N. californicus males were more aggressive ('Napoleon complex') in male-male competition, reducing the likelihood of encounter between the standard-sized male and the female, and thus counterbalancing female preference for standard-sized males. Our results support the hypothesis that male body size is more important to fitness in the low-level polyandrous P. persimilis than in the medium-level polyandrous N. californicus and provide a key example of the implications of sexually selected body size plasticity on mating behaviour.

  19. The tempo and mode of evolution: body sizes of island mammals.

    Science.gov (United States)

    Raia, Pasquale; Meiri, Shai

    2011-07-01

    The tempo and mode of body size evolution on islands are believed to be well known. It is thought that body size evolves relatively quickly on islands toward the mammalian modal value, thus generating extreme cases of size evolution and the island rule. Here, we tested both theories in a phylogenetically explicit context, by using two different species-level mammalian phylogenetic hypotheses limited to sister clades dichotomizing into an exclusively insular and an exclusively mainland daughter nodes. Taken as a whole, mammals were found to show a largely punctuational mode of size evolution. We found that, accounting for this, and regardless of the phylogeny used, size evolution on islands is no faster than on the continents. We compared different selection regimes using a set of Ornstein-Uhlenbeck models to examine the effects of insularity of the mode of evolution. The models strongly supported clade-specific selection regimes. Under this regime, however, an evolutionary model allowing insular species to evolve differently from their mainland relatives performs worse than a model that ignores insularity as a factor. Thus, insular taxa do not experience statistically different selection from their mainland relatives. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  20. Role of media and peers on body change strategies among adult men: is body size important?

    Science.gov (United States)

    McCabe, Marita P; McGreevy, Shauna J

    2011-01-01

    There has been limited previous research that has examined the role of sociocultural influences on body change strategies among adult men. The current study investigated the role of specific types of messages (encouragement, teasing and modelling) from peers and the media on the strategies to change weight among adult men. Differences were evaluated between 526 men aged from 18 to 60 years from three groups (normal weight, overweight and obese) on body image, body change strategies and messages about their body received from peers and the media. Men were primarily drawn from United States, Australia and Europe. Results showed that messages received by men regarding losing weight or increasing muscle size differed according to weight. Body image and media messages were the strongest predictors of losing weight, whereas body image importance and messages from peers were the strongest predictors of increasing muscles. These findings highlight the importance of sociocultural influences on body change strategies among adult males. Copyright © 2010 John Wiley & Sons, Ltd and Eating Disorders Association.

  1. Common Noctule Bats Are Sexually Dimorphic in Migratory Behaviour and Body Size but Not Wing Shape.

    Directory of Open Access Journals (Sweden)

    M Teague O'Mara

    Full Text Available Within the large order of bats, sexual size dimorphism measured by forearm length and body mass is often female-biased. Several studies have explained this through the effects on load carrying during pregnancy, intrasexual competition, as well as the fecundity and thermoregulation advantages of increased female body size. We hypothesized that wing shape should differ along with size and be under variable selection pressure in a species where there are large differences in flight behaviour. We tested whether load carrying, sex differential migration, or reproductive advantages of large females affect size and wing shape dimorphism in the common noctule (Nyctalus noctula, in which females are typically larger than males and only females migrate long distances each year. We tested for univariate and multivariate size and shape dimorphism using data sets derived from wing photos and biometric data collected during pre-migratory spring captures in Switzerland. Females had forearms that are on average 1% longer than males and are 1% heavier than males after emerging from hibernation, but we found no sex differences in other size, shape, or other functional characters in any wing parameters during this pre-migratory period. Female-biased size dimorphism without wing shape differences indicates that reproductive advantages of big mothers are most likely responsible for sexual dimorphism in this species, not load compensation or shape differences favouring aerodynamic efficiency during pregnancy or migration. Despite large behavioural and ecological sex differences, morphology associated with a specialized feeding niche may limit potential dimorphism in narrow-winged bats such as common noctules and the dramatic differences in migratory behaviour may then be accomplished through plasticity in wing kinematics.

  2. Adaptive evolution of body size subject to indirect effect in trophic cascade system.

    Science.gov (United States)

    Wang, Xin; Fan, Meng; Hao, Lina

    2017-09-01

    Trophic cascades represent a classic example of indirect effect and are wide-spread in nature. Their ecological impact are well established, but the evolutionary consequences have received even less theoretical attention. We theoretically and numerically investigate the trait (i.e., body size of consumer) evolution in response to indirect effect in a trophic cascade system. By applying the quantitative trait evolutionary theory and the adaptive dynamic theory, we formulate and explore two different types of eco-evolutionary resource-consumer-predator trophic cascade model. First, an eco-evolutionary model incorporating the rapid evolution is formulated to investigate the effect of rapid evolution of the consumer's body size, and to explore the impact of density-mediate indirect effect on the population dynamics and trait dynamics. Next, by employing the adaptive dynamic theory, a long-term evolutionary model of consumer body size is formulated to evaluate the effect of long-term evolution on the population dynamics and the effect of trait-mediate indirect effect. Those models admit rich dynamics that has not been observed yet in empirical studies. It is found that, both in the trait-mediated and density-mediated system, the body size of consumer in predator-consumer-resource interaction (indirect effect) evolves smaller than that in consumer-resource and predator-consumer interaction (direct effect). Moreover, in the density-mediated system, we found that the evolution of consumer body size contributes to avoiding consumer extinction (i.e., evolutionary rescue). The trait-mediate and density-mediate effects may produce opposite evolutionary response. This study suggests that the trophic cascade indirect effect affects consumer evolution, highlights a more comprehensive mechanistic understanding of the intricate interplay between ecological and evolutionary force. The modeling approaches provide avenue for study on indirect effects from an evolutionary perspective

  3. Race differences in accuracy of self-reported childhood body size among white and black women

    NARCIS (Netherlands)

    Field, AE; Franko, DL; Striegel-Moore, RH; Schreiber, GB; Crawford, PB; Daniels, [No Value

    Objective: To assess the relation of self-reported current and recalled preadolescent body size to measured BMI (kilograms per meter squared) and interviewer's assessment of body size. 4Research Methods and Procedures: This was a prospective cohort study of 1890 white and black women who were 9 to

  4. The island rule of body size demonstrated on individual hosts

    NARCIS (Netherlands)

    Molleman, Freerk; Depoilly, Alexandre; Vernon, Philippe; Müller, Jörg; Bailey, Richard; Jarzabek-Müller, Andrea; Prinzing, Andreas

    2016-01-01

    Aim: Under spatial isolation on oceanic islands, species tend to show extreme body sizes. From the point of view of many colonizers, individual hosts surrounded by phylogenetically distant neighbours are phylogenetically isolated. This study addresses for the first time how phylogenetic isolation

  5. Penis size interacts with body shape and height to influence male attractiveness.

    Science.gov (United States)

    Mautz, Brian S; Wong, Bob B M; Peters, Richard A; Jennions, Michael D

    2013-04-23

    Compelling evidence from many animal taxa indicates that male genitalia are often under postcopulatory sexual selection for characteristics that increase a male's relative fertilization success. There could, however, also be direct precopulatory female mate choice based on male genital traits. Before clothing, the nonretractable human penis would have been conspicuous to potential mates. This observation has generated suggestions that human penis size partly evolved because of female choice. Here we show, based upon female assessment of digitally projected life-size, computer-generated images, that penis size interacts with body shape and height to determine male sexual attractiveness. Positive linear selection was detected for penis size, but the marginal increase in attractiveness eventually declined with greater penis size (i.e., quadratic selection). Penis size had a stronger effect on attractiveness in taller men than in shorter men. There was a similar increase in the positive effect of penis size on attractiveness with a more masculine body shape (i.e., greater shoulder-to-hip ratio). Surprisingly, larger penis size and greater height had almost equivalent positive effects on male attractiveness. Our results support the hypothesis that female mate choice could have driven the evolution of larger penises in humans. More broadly, our results show that precopulatory sexual selection can play a role in the evolution of genital traits.

  6. Does the experience of ownership over a rubber hand change body size perception in anorexia nervosa patients?

    NARCIS (Netherlands)

    Keizer, Anouk; Smeets, Monique A M; Postma, Albert; van Elburg, Annemarie; Dijkerman, H. Chris

    Anorexia nervosa (AN) patients show disturbances in body size experience. Here, malleability of body representation was assessed by inducing the Rubber Hand Illusion (RHI). Specifically the impact of the illusion on body size estimation was investigated.Thirty AN patients and thirty healthy females

  7. Scalloped a member of the Hippo tumor suppressor pathway controls mushroom body size in Drosophila brain by non-canonical regulation of neuroblast proliferation.

    Science.gov (United States)

    Rohith, Basavanahalli Nanjundaiah; Shyamala, Baragur Venkatanarayanasetty

    2017-12-15

    Cell proliferation, growth and survival are three different basic processes which converge at determining a fundamental property -the size of an organism. Scalloped (Sd) is the first characterised transcriptional partner to Yorkie (Yki), the downstream effector of the Hippo pathway which is a highly potential and evolutionarily conserved regulator of organ size. Here we have studied the hypomorphic effect of sd on the development of Mushroom Bodies (MBs) in Drosophila brain. We show that, sd non-function results in an increase in the size of MBs. We demonstrate that, sd regulation on MB size operates through multiple routes. Sd expressed in the differentiated MB neurons, imposes non-cell autonomous repression on the proliferation of MB precursor cells, and Sd expression in the MB neuroblasts (NB) cell autonomously represses mushroom body neuroblast (MBNB) proliferation. Further Sd in Kenyon cells (KCs) imparts a cell autonomous restriction on their growth. Our findings are distinctive because, while the classical sd loss of function phenotypes in eye, wing and lymph gland are reported as loss of tissue or reduced organ size, the present study shows that, Sd inactivation in the developing MB, promotes precursor cell proliferation and results in an increase in the organ size. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. The effect of body size evolution and ecology on encephalization in cave bears and extant relatives.

    Science.gov (United States)

    Veitschegger, Kristof

    2017-06-05

    The evolution of larger brain volumes relative to body size in Mammalia is the subject of an extensive amount of research. Early on palaeontologists were interested in the brain of cave bears, Ursus spelaeus, and described its morphology and size. However, until now, it was not possible to compare the absolute or relative brain size in a phylogenetic context due to the lack of an established phylogeny, comparative material, and phylogenetic comparative methods. In recent years, many tools for comparing traits within phylogenies were developed and the phylogenetic position of cave bears was resolved based on nuclear as well as mtDNA. Cave bears exhibit significantly lower encephalization compared to their contemporary relatives and intraspecific brain mass variation remained rather small. Encephalization was correlated with the combined dormancy-diet score. Body size evolution was a main driver in the degree of encephalization in cave bears as it increased in a much higher pace than brain size. In Ursus spelaeus, brain and body size increase over time albeit differently paced. This rate pattern is different in the highest encephalized bear species within the dataset, Ursus malayanus. The brain size in this species increased while body size heavily decreased compared to its ancestral stage. Early on in the evolution of cave bears encephalization decreased making it one of the least encephalized bear species compared to extant and extinct members of Ursidae. The results give reason to suspect that as herbivorous animals, cave bears might have exhibited a physiological buffer strategy to survive the strong seasonality of their environment. Thus, brain size was probably affected by the negative trade-off with adipose tissue as well as diet. The decrease of relative brain size in the herbivorous Ursus spelaeus is the result of a considerable increase in body size possibly in combination with environmental conditions forcing them to rest during winters.

  9. Body size of commom opossum Didelphis aurita Wied-Neuwied 1826 (Didelphimorphia: Didelphidae on southern brazilian islands

    Directory of Open Access Journals (Sweden)

    CH. Salvador

    Full Text Available The body size of vertebrates isolated on islands can undergo changes due to ecological features of these environments. This study aimed to compare the body size of the common opossum, Didelphis aurita, from different insular populations within the same archipelago in southern Brazil. The opossum populations showed corporal variation and different hypotheses were raised to understand the results. This study constitutes the most detailed body size comparison of a marsupial within different insular populations in the Neotropical zone and the data gathered represents an initial contribution for regional fauna biometric knowledge.

  10. Life course variations in the heritability of body size

    DEFF Research Database (Denmark)

    Zhao, J.; Luan, J.A.; Sharp, S.J.

    aim was to use this approach to investigate the life course variations in heritability of body size. Methods: We analysed height, weight and body mass index variables at 11 time-points in 2,452 individuals (1,225 men, 1,227 women) born in 1946 and enrolled in the MRC National Survey of Health...... and Development (NSHD), with genotypes at 147,949 single nucleotide polymorphisms (SNPs) on Metabochips which were subsequently imputed to 506,255 according to the 1000Genomes project. We obtained genome-wide kinship matrices using genotypes at SNPs on Metabochips and genotypes at all SNPs, which were used.......11(0-0.20), 0.10(0-0.22) for height, weight and body mass index, respectively. Variation in estimates was also seen between alternative procedures. Conclusion: This work supports the utility of large-scale genotype data in heritability estimation and highlights the age-related variability in genetic...

  11. 45 CFR 1607.4 - Functions of a governing body.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Functions of a governing body. 1607.4 Section 1607... GOVERNING BODIES § 1607.4 Functions of a governing body. (a) A governing body shall have at least four... accordance with written policies adopted by the recipient's governing body. (b) In addition to other powers...

  12. Variations in otolith patterns, sizes and body morphometrics of jack mackerel Trachurus japonicus juveniles.

    Science.gov (United States)

    Kanaji, Y; Kishida, M; Watanabe, Y; Kawamura, T; Xie, S; Yamashita, Y; Sassa, C; Tsukamoto, Y

    2010-10-01

    Variations in otolith patterns, sizes and body morphometrics of jack mackerel Trachurus japonicus juveniles were investigated. Under transmitted light, translucent (W(t)) and opaque otoliths (W(o)) were detected in juveniles collected from Wakasa Bay between July 2005 and April 2006, whereas only opaque otoliths (G(o)) were detected in Goto-nada Sea individuals between May and June 2006. Three groups of juveniles were distinguished based on differences in hatch season, otolith size and growth history, and body morphometrics. As T. japonicus has different spawning seasons according to spawning grounds, each group was estimated to hatch in different waters. Juveniles with W(t) otoliths were considered to have stayed in coastal habitat longer, as the hatch area was estimated to be near Wakasa Bay. Juveniles with W(o) and G(o) otoliths appear to recruit to coastal waters at larger size, since their hatch areas were estimated to be far from each collection area. Larger otoliths of W(t) were attributed to otolith accretion after the second growth flexion, which was observed only for W(t) . Standard length of W(t) fish at the second otolith growth flexion was estimated to correspond to recruitment size to coastal rocky reefs in Wakasa Bay. Body morphometrics were correlated with otolith size after removing body size effect, suggesting that morphological variations of T. japonicus juveniles were also associated with the timing of recruitment to coastal habitat. © 2010 The Authors. Journal compilation © 2010 The Fisheries Society of the British Isles.

  13. Silk elasticity as a potential constraint on spider body size.

    Science.gov (United States)

    Rodríguez-Gironés, Miguel A; Corcobado, Guadalupe; Moya-Laraño, Jordi

    2010-10-07

    Silk is known for its strength and extensibility and has played a key role in the radiation of spiders. Individual spiders use different glands to produce silk types with unique sets of proteins. Most research has studied the properties of major ampullate and capture spiral silks and their ecological implications, while little is known about minor ampullate silk, the type used by those spider species studied to date for bridging displacements. A biomechanical model parameterised with available data shows that the minimum radius of silk filaments required for efficient bridging grows with the square root of the spider's body mass, faster than the radius of minor ampullate silk filaments actually produced by spiders. Because the morphology of spiders adapted to walking along or under silk threads is ill suited for moving on a solid surface, for these species there is a negative relationship between body mass and displacement ability. As it stands, the model suggests that spiders that use silk for their displacements are prevented from attaining a large body size if they must track their resources in space. In particular, silk elasticity would favour sexual size dimorphism because males that must use bridging lines to search for females cannot grow large. 2010 Elsevier Ltd. All rights reserved.

  14. Ecological and evolutionary influences on body size and shape in the Galápagos marine iguana (Amblyrhynchus cristatus).

    Science.gov (United States)

    Chiari, Ylenia; Glaberman, Scott; Tarroso, Pedro; Caccone, Adalgisa; Claude, Julien

    2016-07-01

    Oceanic islands are often inhabited by endemic species that have undergone substantial morphological evolutionary change due to processes of multiple colonizations from various source populations, dispersal, and local adaptation. Galápagos marine iguanas are an example of an island endemic exhibiting high morphological diversity, including substantial body size variation among populations and sexes, but the causes and magnitude of this variation are not well understood. We obtained morphological measurements from marine iguanas throughout their distribution range. These data were combined with genetic and local environmental data from each population to investigate the effects of evolutionary history and environmental conditions on body size and shape variation and sexual dimorphism. Our results indicate that body size and shape are highly variable among populations. Sea surface temperature and island perimeter, but not evolutionary history as depicted by phylogeographic patterns in this species, explain variation in body size among populations. Conversely, evolutionary history, but not environmental parameters or island size, was found to influence variation in body shape among populations. Finally, in all populations except one, we found strong sexual dimorphism in body size and shape in which males are larger, with higher heads than females, while females have longer heads than males. Differences among populations suggest that plasticity and/or genetic adaptation may shape body size and shape variation in marine iguanas. This study will help target future investigations to address the contribution of plasticity versus genetic adaptation on size and shape variation in marine iguanas.

  15. Effect of host plant on body size of Frankliniella occidentalis and its correlation with reproductive capacity

    NARCIS (Netherlands)

    Kogel, de W.J.; Bosco, D.; Hoek, van der M.; Mollema, C.

    1999-01-01

    The effect of different host plants on Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) body size was investigated. Thrips from three different populations, from the Netherlands, Italy, and USA, achieved greater body sizes when reared on cucumber than on bean. The same thrips grew

  16. Sea urchins in a high-CO2 world: partitioned effects of body size, ocean warming and acidification on metabolic rate.

    Science.gov (United States)

    Carey, Nicholas; Harianto, Januar; Byrne, Maria

    2016-04-15

    Body size and temperature are the major factors explaining metabolic rate, and the additional factor of pH is a major driver at the biochemical level. These three factors have frequently been found to interact, complicating the formulation of broad models predicting metabolic rates and hence ecological functioning. In this first study of the effects of warming and ocean acidification, and their potential interaction, on metabolic rate across a broad range in body size (two to three orders of magnitude difference in body mass), we addressed the impact of climate change on the sea urchin ITALIC! Heliocidaris erythrogrammain context with climate projections for southeast Australia, an ocean warming hotspot. Urchins were gradually introduced to two temperatures (18 and 23°C) and two pH levels (7.5 and 8.0), at which they were maintained for 2 months. Identical experimental trials separated by several weeks validated the fact that a new physiological steady state had been reached, otherwise known as acclimation. The relationship between body size, temperature and acidification on the metabolic rate of ITALIC! H. erythrogrammawas strikingly stable. Both stressors caused increases in metabolic rate: 20% for temperature and 19% for pH. Combined effects were additive: a 44% increase in metabolism. Body size had a highly stable relationship with metabolic rate regardless of temperature or pH. None of these diverse drivers of metabolism interacted or modulated the effects of the others, highlighting the partitioned nature of how each influences metabolic rate, and the importance of achieving a full acclimation state. Despite these increases in energetic demand there was very limited capacity for compensatory modulating of feeding rate; food consumption increased only in the very smallest specimens, and only in response to temperature, and not pH. Our data show that warming, acidification and body size all substantially affect metabolism and are highly consistent and

  17. Body size and longitudinal body weight changes do not increase mortality in incident peritoneal dialysis patients of the Brazilian peritoneal dialysis multicenter study

    Science.gov (United States)

    da Silva Fernandes, Natália Maria; Bastos, Marcus Gomes; Franco, Márcia Regina Gianotti; Chaoubah, Alfredo; da Glória Lima, Maria; Divino-Filho, José Carolino; Qureshi, Abdul Rashid

    2013-01-01

    OBJECTIVES: To determine the roles of body size and longitudinal body weight changes in the survival of incident peritoneal dialysis patients. PATIENTS AND METHODS: Patients (n = 1911) older than 18 years of age recruited from 114 dialysis centers (Dec/2004-Oct/2007) and participating in the Brazilian Peritoneal Dialysis Multicenter Cohort Study were included. Clinical and laboratory data were collected monthly (except if the patient received a transplant, recovered renal function, was transferred to hemodialysis, or died). RESULTS: Survival analyses were performed using Kaplan-Meier survival curves and Cox proportional hazards. Total follow-up was 34 months. The mean age was 59 years (54% female). The weight category percentages were as follows: underweight: 8%; normal: 51%; overweight: 29%; and obese 12%. The multivariate model showed a higher risk of death for a body mass index 30 kg/m2. Patients were divided into five categories according to quintiles of body weight changes during the first year of dialysis: +7.1%. Patients in the lowest quintile had significantly higher mortality, whereas no negative impact was observed in the other quintiles. CONCLUSION: These findings suggest that overweight/obesity and a positive body weight variation during the first year of peritoneal dialysis therapy do not increase mortality in incident dialysis patients in Brazil. PMID:23420157

  18. Body Image Issues In Lithuanian Magazines Aimed For Children And Adolescents In Relation To Body Mass Index And Body Size Perception Of 16-19 Y. Old Girls During The Last 15 Years

    OpenAIRE

    Tutkuviene, Janina

    2017-01-01

    Mass media plays an important role in forming body image and makes the significant impact on body size perception in children and adolescents. The aim of present study was to reveal trends in depiction of body image cues in Lithuanian magazines aimed for children and adolescents in relation to changes of real body mass index (BMI) and body size perception of 16-19 y. old girls in the year 2000 and the 2015. Three popular journals published both in the year 2000 and the 2015, were chosen for i...

  19. Paradoxical reproduction and body size in the rock lizard, Agama ...

    African Journals Online (AJOL)

    1993-07-05

    Jul 5, 1993 ... The rock lizard Agama atra atra from Namaqualand differs in both body size and reproduction from other populations of this species occurring elsewhere in southern Africa. Both sexes from Namaqualand are significantly larger than their counterparts in the south-western Cape. While reproduction in this ...

  20. Freshwater fishes in Greek lakes: Species richness and body size patterns

    Directory of Open Access Journals (Sweden)

    Anthi Oikonomou

    2015-11-01

    Full Text Available Freshwater ecosystems are widely recognised as hotspots of biodiversity and endemism; thus they are of great value for conservation biogeography. Amongst the taxa found in freshwater ecosystems, fish are the ideal biological model for testing biogeographical patterns and have often been used in large-scale ecological and biogeographical analyses. Lakes of Greece provide a unique opportunity to test biogeographical theories, however, biogeographical studies in Greece at broader, regional, scales, based on the distribution of freshwater species, species richness and endemism, are scarce. The aim of the current study is to test the effect of key environmental factors and spatial variables on species richness of lacustrine fishes and to test their effect on species’ size distributions. We assembled datasets of species richness and body size and environmental (predictor factors for 13 Greek lakes. Model selection procedures revealed that fish species richness increased with ecosystem area and decreased with altitude. In addition, our results showed that latitude per se is a good predictor of body size. Indeed, the mean size of lacustrine communities in the northern and southern lake ecosystems differed significantly. These patterns reflect the biogeographical history of these areas and highlight the crucial role connectivity plays in communities’ species composition.

  1. Balancing the dilution and oddity effects: decisions depend on body size.

    Directory of Open Access Journals (Sweden)

    Gwendolen M Rodgers

    Full Text Available Grouping behaviour, common across the animal kingdom, is known to reduce an individual's risk of predation; particularly through dilution of individual risk and predator confusion (predator inability to single out an individual for attack. Theory predicts greater risk of predation to individuals more conspicuous to predators by difference in appearance from the group (the 'oddity' effect. Thus, animals should choose group mates close in appearance to themselves (eg. similar size, whilst also choosing a large group.We used the Trinidadian guppy (Poecilia reticulata, a well known model species of group-living freshwater fish, in a series of binary choice trials investigating the outcome of conflict between preferences for large and phenotypically matched groups along a predation risk gradient. We found body-size dependent differences in the resultant social decisions. Large fish preferred shoaling with size-matched individuals, while small fish demonstrated no preference. There was a trend towards reduced preferences for the matched shoal under increased predation risk. Small fish were more active than large fish, moving between shoals more frequently. Activity levels increased as predation risk decreased. We found no effect of unmatched shoal size on preferences or activity.Our results suggest that predation risk and individual body size act together to influence shoaling decisions. Oddity was more important for large than small fish, reducing in importance at higher predation risks. Dilution was potentially of limited importance at these shoal sizes. Activity levels may relate to how much sampling of each shoal was needed by the test fish during decision making. Predation pressure may select for better decision makers to survive to larger size, or that older, larger fish have learned to make shoaling decisions more efficiently, and this, combined with their size relative to shoal-mates, and attractiveness as prey items influences shoaling

  2. Porters of the eastern hills of Nepal: Body size and load weight.

    Science.gov (United States)

    Malville, Nancy J.

    1999-01-01

    This study documents the activities of 635 porters transporting goods along three traditional trade routes of eastern Nepal. Nearly 95% of the porters were male. They ranged in age from 10-65 years, and most of them had begun to perform long-distance portage at 12-15 years of age. Mean body mass and height of adult males in the combined sample (n = 438) was 49.7 +/- 5.0 kg and 155.5 +/- 6.5 cm, respectively. Adult males age 20-49 years carried loads of 73 +/- 15 kg, equivalent to 146% +/- 30% of body mass. Body size of adult males was not a strong predictor of load weight. The correlation between body mass and load was r = 0.24 (P porters to carry such large loads in spite of their small body size is the ability to pace themselves by making frequent rest stops. Heart rate monitoring of 26 adult male commercial porters demonstrated how porters regulate heart rate and energy expenditure by resting the load every two to three minutes on the T-headed walking stick (tokma) and by setting the load periodically on load-resting platforms (chautaras) for longer recovery periods. Am. J. Hum. Biol. 11:1-11, 1999. Copyright 1999 Wiley-Liss, Inc.

  3. Geographic variation in body size and its relationship with environmental gradients in the Oriental Garden Lizard, Calotes versicolor.

    Science.gov (United States)

    Wei, Xiaomei; Yan, Linmiao; Zhao, Chengjian; Zhang, Yueyun; Xu, Yongli; Cai, Bo; Jiang, Ni; Huang, Yong

    2018-05-01

    Patterns of geographic variation in body size are predicted to evolve as adaptations to local environmental gradients. However, many of these clinal patterns in body size, such as Bergmann's rule, are controversial and require further investigation into ectotherms such as reptiles on a regional scale. To examine the environmental variables (temperature, precipitation, topography and primary productivity) that shaped patterns of geographic variation in body size in the reptile Calotes versicolor , we sampled 180 adult specimens (91 males and 89 females) at 40 locations across the species range in China. The MANOVA results suggest significant sexual size dimorphism in C. versicolor ( F 23,124  = 11.32, p  body size of C. versicolor differed for males and females, but mechanisms related to heat balance and water availability hypotheses were involved in both sexes. Temperature seasonality, precipitation of the driest month, precipitation seasonality, and precipitation of the driest quarter were the most important predictors of variation in body size in males, whereas mean precipitation of the warmest quarter, mean temperature of the wettest quarter, precipitation seasonality, and precipitation of the wettest month were most important for body size variation in females. The discrepancy between patterns of association between the sexes suggested that different selection pressures may be acting in males and females.

  4. Intra- and trans-generational costs of reduced female body size caused by food limitation early in life in mites.

    Directory of Open Access Journals (Sweden)

    Andreas Walzer

    Full Text Available Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs.Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons.Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism - females are the larger sex and thus more strongly affected by maternal stress than the smaller males - and to sexually selected lower plasticity of male body size.

  5. Intra- and trans-generational costs of reduced female body size caused by food limitation early in life in mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2013-01-01

    Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons. Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism - females are the larger sex and thus more strongly affected by maternal stress than the smaller males - and to sexually selected lower plasticity of male body size.

  6. Body Image Issues In Lithuanian Magazines Aimed For Children And Adolescents In Relation To Body Mass Index And Body Size Perception Of 16-19 Y. Old Girls During The Last 15 Years.

    Science.gov (United States)

    Tutkuviene, Janina; Misiute, Agne; Strupaite, Ieva; Paulikaite, Gintare; Pavlovskaja, Erika

    2017-03-01

    Mass media plays an important role in forming body image and makes the significant impact on body size perception in children and adolescents. The aim of present study was to reveal trends in depiction of body image cues in Lithuanian magazines aimed for children and adolescents in relation to changes of real body mass index (BMI) and body size perception of 16-19 y. old girls in the year 2000 and the 2015. Three popular journals published both in the year 2000 and the 2015, were chosen for in-depth analysis of their contents (the periodicity of different topics was counted and compared). Attention given to a healthy body image has increased and the promotion of especially skinny females’ body has decreased during the last 15 years from the dominant type in the year 2000 to depiction of slightly thin or normal body build in the 2015. However, the real BMI of 16-19 y. old Lithuanian girls has significantly increased during the 2000-2015 period (from 20.09 till 21.32 kg/m²; pimage issues in mass media (magazines aimed for adolescent girls) were in parallel with the proper self-esteem of body size in adolescent girls.

  7. Some like it hot... : the evolution and genetics of temperature dependent body size in Drosophila melanogaster

    NARCIS (Netherlands)

    Bochdanovits, Z. (Zoltán)

    2003-01-01

    Body size is one of the most obvious and most important characteristic of any organism. A thorough understanding of how and why a certain individual obtains a specific body size, given its evolutionary history and ecological context, is a fundamental question in biology. One special case of

  8. How Big Is It Really? Assessing the Efficacy of Indirect Estimates of Body Size in Asian Elephants.

    Directory of Open Access Journals (Sweden)

    Simon N Chapman

    Full Text Available Information on an organism's body size is pivotal in understanding its life history and fitness, as well as helping inform conservation measures. However, for many species, particularly large-bodied wild animals, taking accurate body size measurements can be a challenge. Various means to estimate body size have been employed, from more direct methods such as using photogrammetry to obtain height or length measurements, to indirect prediction of weight using other body morphometrics or even the size of dung boli. It is often unclear how accurate these measures are because they cannot be compared to objective measures. Here, we investigate how well existing estimation equations predict the actual body weight of Asian elephants Elephas maximus, using body measurements (height, chest girth, length, foot circumference and neck circumference taken directly from a large population of semi-captive animals in Myanmar (n = 404. We then define new and better fitting formulas to predict body weight in Myanmar elephants from these readily available measures. We also investigate whether the important parameters height and chest girth can be estimated from photographs (n = 151. Our results show considerable variation in the ability of existing estimation equations to predict weight, and that the equations proposed in this paper predict weight better in almost all circumstances. We also find that measurements from standardised photographs reflect body height and chest girth after applying minor adjustments. Our results have implications for size estimation of large wild animals in the field, as well as for management in captive settings.

  9. Depictive and metric body size estimation in anorexia nervosa and bulimia nervosa: A systematic review and meta-analysis.

    Science.gov (United States)

    Mölbert, Simone Claire; Klein, Lukas; Thaler, Anne; Mohler, Betty J; Brozzo, Chiara; Martus, Peter; Karnath, Hans-Otto; Zipfel, Stephan; Giel, Katrin Elisabeth

    2017-11-01

    A distorted representation of one's own body is a diagnostic criterion and core psychopathology of both anorexia nervosa (AN) and bulimia nervosa (BN). Despite recent technical advances in research, it is still unknown whether this body image disturbance is characterized by body dissatisfaction and a low ideal weight and/or includes a distorted perception or processing of body size. In this article, we provide an update and meta-analysis of 42 articles summarizing measures and results for body size estimation (BSE) from 926 individuals with AN, 536 individuals with BN and 1920 controls. We replicate findings that individuals with AN and BN overestimate their body size as compared to controls (ES=0.63). Our meta-regression shows that metric methods (BSE by direct or indirect spatial measures) yield larger effect sizes than depictive methods (BSE by evaluating distorted pictures), and that effect sizes are larger for patients with BN than for patients with AN. To interpret these results, we suggest a revised theoretical framework for BSE that accounts for differences between depictive and metric BSE methods regarding the underlying body representations (conceptual vs. perceptual, implicit vs. explicit). We also discuss clinical implications and argue for the importance of multimethod approaches to investigate body image disturbance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Impact of Base Functional Component Types on Software Functional Size based Effort Estimation

    OpenAIRE

    Gencel, Cigdem; Buglione, Luigi

    2008-01-01

    Software effort estimation is still a significant challenge for software management. Although Functional Size Measurement (FSM) methods have been standardized and have become widely used by the software organizations, the relationship between functional size and development effort still needs further investigation. Most of the studies focus on the project cost drivers and consider total software functional size as the primary input to estimation models. In this study, we investigate whether u...

  11. Body size, skills, and income: evidence from 150,000 teenage siblings.

    Science.gov (United States)

    Lundborg, Petter; Nystedt, Paul; Rooth, Dan-Olof

    2014-10-01

    We provide new evidence on the long-run labor market penalty of teenage overweight and obesity using unique and large-scale data on 150,000 male siblings from the Swedish military enlistment. Our empirical analysis provides four important results. First, we provide the first evidence of a large adult male labor market penalty for being overweight or obese as a teenager. Second, we replicate this result using data from the United States and the United Kingdom. Third, we note a strikingly strong within-family relationship between body size and cognitive skills/noncognitive skills. Fourth, a large part of the estimated body-size penalty reflects lower skill acquisition among overweight and obese teenagers. Taken together, these results reinforce the importance of policy combating early-life obesity in order to reduce healthcare expenditures as well as poverty and inequalities later in life.

  12. Neonatal CPR: room at the top—a mathematical study of optimal chest compression frequency versus body size

    OpenAIRE

    Babbs, Charles F; Meyer, Andrew; Nadkarni, Vinay

    2009-01-01

    Objective: To explore in detail the expected magnitude of systemic perfusion pressure during standard CPR as a function of compression frequency for different sized people from neonate to adult. Method: A 7-compartment mathematical model of the human cardiopulmonary system—upgraded to include inertance of blood columns in the aorta and vena cavae—was exercised with parameters scaled to reflect changes in body weight from 1 to 70 kg. Results: Maximal systemic perfusion pressure occurs at chest...

  13. Effect of directional selection for body size on fluctuating asymmetry ...

    Indian Academy of Sciences (India)

    In this study, we investigated whether stress caused by artificial bidirectional selection for body size has any effect on the levels of FA of different morphological traits in Drosophila ananassae. The realised heritability (h2) was higher in low-line females and high-line males, which suggests an asymmetrical response to ...

  14. Intra- and Trans-Generational Costs of Reduced Female Body Size Caused by Food Limitation Early in Life in Mites

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2013-01-01

    Background Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Methodology/Principal Findings Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons. Conclusions/Significance Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism – females are the larger sex and thus more strongly affected by maternal stress than the smaller males – and to sexually selected lower plasticity of male body size. PMID:24265745

  15. The Effect of Body Size in Mercury Accumulation Biokinetic of Cockle Shell (Anadara Granosa)

    International Nuclear Information System (INIS)

    Wahyu Retno Prihatiningsih

    2007-01-01

    Accumulation of mercury biokinetic in cockle shell (Anadara granosa) through water pathway has been investigated under laboratory condition. The objective of research is to find the effect of body size in mercury biokinetic of Anadara granosa and to find bioindicator based on biokinetic parameter. The research shows that body size of Anadara granosa give an effect to concentration factor and could barrier mercury contaminant. Concentration factor for size 1.9, 2.5 and 3.9 cm of biota moving high and reach steady state condition after 24 days. Concentration factor of Anadara granosa in size 1.9, 2.5 and 3.9 is 0.1476, 0.1645 and 0.2573 day. Based on mechanism of mercury biokinetic process, it was proof that Anadara granosa is an ideal invertebrate for bioindicator. (author)

  16. Body Size of Contemporary Youth in Different Parts of the World

    Science.gov (United States)

    Meredith, Howard V.

    1969-01-01

    Based on body size measurements accumulated between 1950-1960, comparisons were made of 13-year-old girls and 15-year-old boys from North and South America, northern, central, and southwest Asia, Oceania, Australia, Africa, the Near East, and Europe. (DO)

  17. Density, body size, and reproduction of feral house mice on Gough ...

    African Journals Online (AJOL)

    1991-05-02

    May 2, 1991 ... 1992,27(1). Density, body size, and reproduction of feral house mice on Gough Island ... and mean monthly air temperatures (at sea level) range between 9°C ..... Concern about the adverse effect of introduced mice on island.

  18. The Influence of Age and Sex on Genetic Associations with Adult Body Size and Shape

    DEFF Research Database (Denmark)

    Winkler, Thomas W; Justice, Anne E; Graff, Mariaelisa

    2015-01-01

    Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially...... (G x AGE), sex-specific effects (G x SEX) or age-specific effects that differed between men and women (G x AGE x SEX). For BMI, we identified 15 loci (11 previously established for main effects, four novel) that showed significant (FDR... effects on WHRadjBMI. These results may provide further insights into the biology that underlies weight change with age or the sexually dimorphism of body shape....

  19. Body condition, diet and ecosystem function of red deer (Cervus elaphus in a fenced nature reserve

    Directory of Open Access Journals (Sweden)

    Camilla Fløjgaard

    2017-07-01

    Full Text Available Body condition, as a sign of animal welfare, is of management concern in rewilding projects where fenced animals are subject to winter starvation, which may conflict with animal welfare legislation. Investigating the relationship between body condition, age, sex, diet quality and diet composition is therefore relevant to increase understanding of herbivores' ecosystem function and to inform management. In this study, we focused on red deer, Cervus elaphus, in a fenced nature reserve in Denmark, where the deer are managed as ecosystem engineers to contribute to biodiversity conservation. We measured body mass and body size of 91 culled red deer, and determined diet composition using DNA metabarcoding and diet quality using fecal nitrogen on 246 fecal samples. We found that body condition was predicted by age and diet composition, but not diet quality. We also found that individuals of different body condition had different diets, i.e., the fecal samples of red deer in poorer body condition contained significantly more Ericaceae sequences than red deer in good body condition. This may imply that certain functions of red deer in ecosystems, such as regeneration of heather by grazing, may depend on variation in body condition within the population. Our findings call for the need to consider the consequences of management practices, including culling or supplemental feeding, on the outcomes of habitat restoration, and more broadly underline the importance of preserving the overall breath of herbivore ecosystem functions for effective biodiversity conservation.

  20. Size-dependent plastic deformation of twinned nanopillars in body-centered cubic tungsten

    Science.gov (United States)

    Xu, Shuozhi; Startt, Jacob K.; Payne, Thomas G.; Deo, Chaitanya S.; McDowell, David L.

    2017-05-01

    Compared with face-centered cubic metals, twinned nanopillars in body-centered cubic (BCC) systems are much less explored partly due to the more complicated plastic deformation behavior and a lack of reliable interatomic potentials for the latter. In this paper, the fault energies predicted by two semi-empirical interatomic potentials in BCC tungsten (W) are first benchmarked against density functional theory calculations. Then, the more accurate potential is employed in large scale molecular dynamics simulations of tensile and compressive loading of twinned nanopillars in BCC W with different cross sectional shapes and sizes. A single crystal, a twinned crystal, and single crystalline nanopillars are also studied as references. Analyses of the stress-strain response and defect nucleation reveal a strong tension-compression asymmetry and a weak pillar size dependence in the yield strength. Under both tensile and compressive loading, plastic deformation in the twinned nanopillars is dominated by dislocation slip on {110} planes that are nucleated from the intersections between the twin boundary and the pillar surface. It is also found that the cross sectional shape of nanopillars affects the strength and the initial site of defect nucleation but not the overall stress-strain response and plastic deformation behavior.

  1. Functional genomics in the study of mind-body therapies.

    Science.gov (United States)

    Niles, Halsey; Mehta, Darshan H; Corrigan, Alexandra A; Bhasin, Manoj K; Denninger, John W

    2014-01-01

    Mind-body therapies (MBTs) are used throughout the world in treatment, disease prevention, and health promotion. However, the mechanisms by which MBTs exert their positive effects are not well understood. Investigations into MBTs using functional genomics have revolutionized the understanding of MBT mechanisms and their effects on human physiology. We searched the literature for the effects of MBTs on functional genomics determinants using MEDLINE, supplemented by a manual search of additional journals and a reference list review. We reviewed 15 trials that measured global or targeted transcriptomic, epigenomic, or proteomic changes in peripheral blood. Sample sizes ranged from small pilot studies (n=2) to large trials (n=500). While the reliability of individual genes from trial to trial was often inconsistent, genes related to inflammatory response, particularly those involved in the nuclear factor-kappa B (NF-κB) pathway, were consistently downregulated across most studies. In general, existing trials focusing on gene expression changes brought about by MBTs have revealed intriguing connections to the immune system through the NF-κB cascade, to telomere maintenance, and to apoptotic regulation. However, these findings are limited to a small number of trials and relatively small sample sizes. More rigorous randomized controlled trials of healthy subjects and specific disease states are warranted. Future research should investigate functional genomics areas both upstream and downstream of MBT-related gene expression changes-from epigenomics to proteomics and metabolomics.

  2. Scaling of lifting forces in relation to object size in whole body lifting

    NARCIS (Netherlands)

    Kingma, I.; van Dieen, J.H.; Toussaint, H.M.

    2005-01-01

    Subjects prepare for a whole body lifting movement by adjusting their posture and scaling their lifting forces to the expected object weight. The expectancy is based on visual and haptic size cues. This study aimed to find out whether lifting force overshoots related to object size cues disappear or

  3. Comparison of organ doses in human phantoms: variations due to body size and posture

    International Nuclear Information System (INIS)

    Feng, Xu; Xiang-Hong, Jia; Xue-Jun, Yu; Zhan-Chun, Pan; Qian, Liu; Chun-Xin, Yang

    2017-01-01

    Organ dose calculations performed using human phantoms can provide estimates of astronauts' health risks due to cosmic radiation. However, the characteristics of such phantoms strongly affect the estimation precision. To investigate organ dose variations with body size and posture in human phantoms, a non-uniform rational B-spline boundary surfaces model was constructed based on cryo-section images. This model was used to establish four phantoms with different body size and posture parameters, whose organs parameters were changed simultaneously and which were voxelised with 4x4x4 mm"3 resolution. Then, using Monte Carlo transport code, the organ doses caused by ≤500 MeV isotropic incident protons were calculated. The dose variations due to body size differences within a certain range were negligible, and the doses received in crouching and standing-up postures were similar. Therefore, a standard Chinese phantom could be established, and posture changes cannot effectively protect astronauts during solar particle events. (authors)

  4. Body size shifts and early warning signals precede the historic collapse of whale stocks.

    Science.gov (United States)

    Clements, Christopher F; Blanchard, Julia L; Nash, Kirsty L; Hindell, Mark A; Ozgul, Arpat

    2017-06-22

    Predicting population declines is a key challenge in the face of global environmental change. Abundance-based early warning signals have been shown to precede population collapses; however, such signals are sensitive to the low reliability of abundance estimates. Here, using historical data on whales harvested during the 20th century, we demonstrate that early warning signals can be present not only in the abundance data, but also in the more reliable body size data of wild populations. We show that during the period of commercial whaling, the mean body size of caught whales declined dramatically (by up to 4 m over a 70-year period), leading to early warning signals being detectable up to 40 years before the global collapse of whale stocks. Combining abundance and body size data can reduce the length of the time series required to predict collapse, and decrease the chances of false positive early warning signals.

  5. Interrelationships of Hormones, Diet, Body Size and Breast Cancer among Hispanic Women

    National Research Council Canada - National Science Library

    Peltz, Gerson

    2005-01-01

    ...). The training program will focus on breast cancer etiology, specifically the interrelationships between hormones, diet, body size, and breast cancer among Hispanic women in the Lower Rio Grande Valley (LRGV...

  6. Size relationships of different body parts in the three dipteran species Drosophila melanogaster, Ceratitis capitata and Musca domestica.

    Science.gov (United States)

    Siomava, Natalia; Wimmer, Ernst A; Posnien, Nico

    2016-06-01

    Body size is an integral feature of an organism that influences many aspects of life such as fecundity, life span and mating success. Size of individual organs and the entire body size represent quantitative traits with a large reaction norm, which are influenced by various environmental factors. In the model system Drosophila melanogaster, pupal size and adult traits, such as tibia and thorax length or wing size, accurately estimate the overall body size. However, it is unclear whether these traits can be used in other flies. Therefore, we studied changes in size of pupae and adult organs in response to different rearing temperatures and densities for D. melanogaster, Ceratitis capitata and Musca domestica. We confirm a clear sexual size dimorphism (SSD) for Drosophila and show that the SSD is less uniform in the other species. Moreover, the size response to changing growth conditions is sex dependent. Comparison of static and evolutionary allometries of the studied traits revealed that response to the same environmental variable is genotype specific but has similarities between species of the same order. We conclude that the value of adult traits as estimators of the absolute body size may differ among species and the use of a single trait may result in wrong assumptions. Therefore, we suggest using a body size coefficient computed from several individual measurements. Our data is of special importance for monitoring activities of natural populations of the three dipteran flies, since they are harmful species causing economical damage (Drosophila, Ceratitis) or transferring diseases (Musca).

  7. Geographic body size variation in the periodical cicadas Magicicada: implications for life cycle divergence and local adaptation.

    Science.gov (United States)

    Koyama, T; Ito, H; Kakishima, S; Yoshimura, J; Cooley, J R; Simon, C; Sota, T

    2015-06-01

    Seven species in three species groups (Decim, Cassini and Decula) of periodical cicadas (Magicicada) occupy a wide latitudinal range in the eastern United States. To clarify how adult body size, a key trait affecting fitness, varies geographically with climate conditions and life cycle, we analysed the relationships of population mean head width to geographic variables (latitude, longitude, altitude), habitat annual mean temperature (AMT), life cycle and species differences. Within species, body size was larger in females than males and decreased with increasing latitude (and decreasing habitat AMT), following the converse Bergmann's rule. For the pair of recently diverged 13- and 17-year species in each group, 13-year cicadas were equal in size or slightly smaller on average than their 17-year counterparts despite their shorter developmental time. This fact suggests that, under the same climatic conditions, 17-year cicadas have lowered growth rates compared to their 13-years counterparts, allowing 13-year cicadas with faster growth rates to achieve body sizes equivalent to those of their 17-year counterparts at the same locations. However, in the Decim group, which includes two 13-year species, the more southerly, anciently diverged 13-year species (Magicicada tredecim) was characterized by a larger body size than the other, more northerly 13- and 17-year species, suggesting that local adaptation in warmer habitats may ultimately lead to evolution of larger body sizes. Our results demonstrate how geographic clines in body size may be maintained in sister species possessing different life cycles. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  8. Weber's Illusion and Body Shape: Anisotropy of Tactile Size Perception on the Hand

    Science.gov (United States)

    Longo, Matthew R.; Haggard, Patrick

    2011-01-01

    The perceived distance between touches on a single skin surface is larger on regions of high tactile sensitivity than those with lower acuity, an effect known as "Weber's illusion". This illusion suggests that tactile size perception involves a representation of the perceived size of body parts preserving characteristics of the somatosensory…

  9. The bold and the beautiful. Influence of body size of televised media models on body dissatisfaction and actual food intake

    NARCIS (Netherlands)

    Anschutz, Doeschka J; Engels, Rutger C M E; Becker, Eni S; van Strien, Tatjana

    2008-01-01

    The effects of exposure to televised thin and average size models on body dissatisfaction and actual food intake were examined. Normal weight female students (N=104) were exposed to a 30-min movie clip featuring beautiful girls. Half of them viewed the movie clip in normal screen size (4:3) and the

  10. Size Effect of the 2-D Bodies on the Geothermal Gradient and Q-A Plot

    Science.gov (United States)

    Thakur, M.; Blackwell, D. D.

    2009-12-01

    Using numerical models we have investigated some of the criticisms on the Q-A plot of related to the effect of size of the body on the slope and reduced heat flow. The effects of horizontal conduction depend on the relative difference of radioactivity between the body and the country rock (assuming constant thermal conductivity). Horizontal heat transfer due to different 2-D bodies was numerically studied in order to quantify resulting temperature differences at the Moho and errors on the predication of Qr (reduced heat flow). Using the two end member distributions of radioactivity, the step model (thickness 10km) and exponential model, different 2-D models of horizontal scale (width) ranging from 10 -500 km were investigated. Increasing the horizontal size of the body tends to move observations closer towards the 1-D solution. A temperature difference of 50 oC is produced (for the step model) at Moho between models of width 10 km versus 500 km. In other words the 1-D solution effectively provides large scale averaging in terms of heat flow and temperature field in the lithosphere. For bodies’ ≤ 100 km wide the geotherms at shallower levels are affected, but at depth they converge and are 50 oC lower than that of the infinite plate model temperature. In case of 2-D bodies surface heat flow is decreased due to horizontal transfer of heat, which will shift the Q-A point vertically downward on the Q-A plot. The smaller the size of the body, the more will be the deviation from the 1-D solution and the more will be the movement of Q-A point downwards on a Q-A plot. On the Q-A plot, a limited points of bodies of different sizes with different radioactivity contrast (for the step and exponential model), exactly reproduce the reduced heat flow Qr. Thus the size of the body can affect the slope on a Q-A plot but Qr is not changed. Therefore, Qr ~ 32 mWm-2 obtained from the global terrain average Q-A plot represents the best estimate of stable continental mantle heat

  11. The Relationship Between 
Body Mass Index and Sexual Function in Endometrial Cancer
.

    Science.gov (United States)

    Garcia, Rubi M; Hanlon, Alexandra; Small, William; Strauss, Jonathan B; Lin, Lillie; Wells, Jessica; Bruner, Deborah W

    2018-01-01

    To explore the association between pretreatment body mass index (BMI) and post-treatment sexual function in women treated for endometrial cancer. 
. 28 postmenopausal women treated with vaginal brachytherapy (VBT) took part in this multisite exploratory secondary analysis at the University of Pennsylvania and Northwestern University. 
. Secondary data analysis was used to determine if pretreatment BMI is associated with post-VBT sexual function in postmenopausal women treated for endometrial cancer at baseline and at six months post-treatment. Because of small sample size, participants were dichotomized according to enrollment BMI. Both groups had poor sexual function at baseline. Although improved function was observed with time, neither group reached a score indicating healthy sexual function.
. Understanding factors that influence sexual health in patients with gynecologic cancer can improve post-treatment quality of life. 
.

  12. Myonuclear domain size and myosin isoform expression in muscle fibres from mammals representing a 100,000-fold difference in body size.

    Science.gov (United States)

    Liu, Jing-Xia; Höglund, Anna-Stina; Karlsson, Patrick; Lindblad, Joakim; Qaisar, Rizwan; Aare, Sudhakar; Bengtsson, Ewert; Larsson, Lars

    2009-01-01

    This comparative study of myonuclear domain (MND) size in mammalian species representing a 100,000-fold difference in body mass, ranging from 25 g to 2500 kg, was undertaken to improve our understanding of myonuclear organization in skeletal muscle fibres. Myonuclear domain size was calculated from three-dimensional reconstructions in a total of 235 single muscle fibre segments at a fixed sarcomere length. Irrespective of species, the largest MND size was observed in muscle fibres expressing fast myosin heavy chain (MyHC) isoforms, but in the two smallest mammalian species studied (mouse and rat), MND size was not larger in the fast-twitch fibres expressing the IIA MyHC isofom than in the slow-twitch type I fibres. In the larger mammals, the type I fibres always had the smallest average MND size, but contrary to mouse and rat muscles, type IIA fibres had lower mitochondrial enzyme activities than type I fibres. Myonuclear domain size was highly dependent on body mass in the two muscle fibre types expressed in all species, i.e. types I and IIA. Myonuclear domain size increased in muscle fibres expressing both the beta/slow (type I; r = 0.84, P fast IIA MyHC isoform (r = 0.90; P muscle fibre type, independent of species. However, myosin isoform expression is not the sole protein determining MND size, and other protein systems, such as mitochondrial proteins, may be equally or more important determinants of MND size.

  13. Ideal Body Size as a Mediator for the Gender-Specific Association Between Socioeconomic Status and Body Mass Index: Evidence From an Upper-Middle-Income Country in the African Region.

    OpenAIRE

    Yepes Maryam; Maurer Jürgen; Stringhini Silvia; Viswanathan Barathi; Gedeon Jude; Bovet Pascal

    2016-01-01

    While obesity continues to rise globally the associations between body size gender and socioeconomic status (SES) seem to vary in different populations and little is known on the contribution of perceived ideal body size in the social disparity of obesity in African countries. We examined the gender and socioeconomic patterns of body mass index (BMI) and perceived ideal body size in the Seychelles a middle income small island state in the African region. We also assessed the potential role of...

  14. Generating size-controlled embryoid bodies using laser direct-write

    International Nuclear Information System (INIS)

    Dias, A D; Corr, D T; Unser, A M; Xie, Y; Chrisey, D B

    2014-01-01

    Embryonic stem cells (ESCs) have the potential to self-renew and differentiate into any specialized cell type. One common method to differentiate ESCs in vitro is through embryoid bodies (EBs), three-dimensional cellular aggregates that spontaneously self-assemble and generally express markers for the three germ layers, endoderm, ectoderm, and mesoderm. It has been previously shown that both EB size and 2D colony size each influence differentiation. We hypothesized that we could control the size of the EB formed by mouse ESCs (mESCs) by using a cell printing method, laser direct-write (LDW), to control both the size of the initial printed colony and the local cell density in printed colonies. After printing mESCs at various printed colony sizes and printing densities, two-way ANOVAs indicated that the EB diameter was influenced by printing density after three days (p = 0.0002), while there was no effect of the printed colony diameter on the EB diameter at the same timepoint (p = 0.74). There was no significant interaction between these two factors. Tukey's honestly significant difference test showed that high-density colonies formed significantly larger EBs, suggesting that printed mESCs quickly aggregate with nearby cells. Thus, EBs can be engineered to a desired size by controlling printing density, which will influence the design of future differentiation studies. Herein, we highlight the capacity of LDW to control the local cell density and colony size independently, at prescribed spatial locations, potentially leading to better stem cell maintenance and directed differentiation. (paper)

  15. Functional, size and taxonomic diversity of fish along a depth gradient in the deep sea.

    Science.gov (United States)

    Mindel, Beth L; Neat, Francis C; Trueman, Clive N; Webb, Thomas J; Blanchard, Julia L

    2016-01-01

    Biodiversity is well studied in ecology and the concept has been developed to include traits of species, rather than solely taxonomy, to better reflect the functional diversity of a system. The deep sea provides a natural environmental gradient within which to study changes in different diversity metrics, but traits of deep-sea fish are not widely known, hampering the application of functional diversity to this globally important system. We used morphological traits to determine the functional richness and functional divergence of demersal fish assemblages along the continental slope in the Northeast Atlantic, at depths of 300-2,000 m. We compared these metrics to size diversity based on individual body size and species richness. Functional richness and size diversity showed similar patterns, with the highest diversity at intermediate depths; functional divergence showed the opposite pattern, with the highest values at the shallowest and deepest parts of the study site. Species richness increased with depth. The functional implications of these patterns were deduced by examining depth-related changes in morphological traits and the dominance of feeding guilds as illustrated by stable isotope analyses. The patterns in diversity and the variation in certain morphological traits can potentially be explained by changes in the relative dominance of pelagic and benthic feeding guilds. All measures of diversity examined here suggest that the deep areas of the continental slope may be equally or more diverse than assemblages just beyond the continental shelf.

  16. Functional, size and taxonomic diversity of fish along a depth gradient in the deep sea

    Directory of Open Access Journals (Sweden)

    Beth L. Mindel

    2016-09-01

    Full Text Available Biodiversity is well studied in ecology and the concept has been developed to include traits of species, rather than solely taxonomy, to better reflect the functional diversity of a system. The deep sea provides a natural environmental gradient within which to study changes in different diversity metrics, but traits of deep-sea fish are not widely known, hampering the application of functional diversity to this globally important system. We used morphological traits to determine the functional richness and functional divergence of demersal fish assemblages along the continental slope in the Northeast Atlantic, at depths of 300–2,000 m. We compared these metrics to size diversity based on individual body size and species richness. Functional richness and size diversity showed similar patterns, with the highest diversity at intermediate depths; functional divergence showed the opposite pattern, with the highest values at the shallowest and deepest parts of the study site. Species richness increased with depth. The functional implications of these patterns were deduced by examining depth-related changes in morphological traits and the dominance of feeding guilds as illustrated by stable isotope analyses. The patterns in diversity and the variation in certain morphological traits can potentially be explained by changes in the relative dominance of pelagic and benthic feeding guilds. All measures of diversity examined here suggest that the deep areas of the continental slope may be equally or more diverse than assemblages just beyond the continental shelf.

  17. Body Size and the Risk of Primary Hyperparathyroidism in Women: A Cohort Study.

    Science.gov (United States)

    Vaidya, Anand; Curhan, Gary C; Paik, Julie M; Wang, Molin; Taylor, Eric N

    2017-09-01

    Greater body weight and fat mass have been associated with higher serum parathyroid hormone levels and a higher prevalence of primary hyperparathyroidism (P-HPTH) in women. However, prospective studies to evaluate whether greater body size associates with a higher incidence of developing P-HPTH have not been reported. We investigated whether greater body size was independently associated with a higher risk for developing P-HPTH in women. We conducted a prospective cohort study of 85,013 female participants in the Nurses' Health Study I followed for up to 26 years. Body size was measured via multiple metrics: weight, body mass index (BMI), and waist circumference (WC). Weight and BMI were assessed every 2 years from 1986 to 2012, and WC was assessed in 1986, 1996, and 2000. Detailed dietary and demographic exposures were quantified via validated biennial questionnaires. Incident cases of P-HPTH were confirmed by individual medical record review. Cox proportional hazards models were used to evaluate whether WC, weight, and BMI were independent risk factors for developing P-HPTH. Models were adjusted for demographic variables, comorbidities, medications, intakes of calcium and vitamin D, and exposure to ultraviolet light. We confirmed 491 incident cases of P-HPTH during 2,128,068 person-years of follow-up. The multivariable-adjusted relative risks for incident P-HPTH increased across quartiles of WC: Q1, ref; Q2, 1.34 (0.97, 1.86); Q3, 1.70 (1.24, 2.31); Q4, 2.27 (1.63, 3.18); p trend < 0.001. Similarly, the multivariable-adjusted risks for incident P-HPTH increased across quartiles of weight: Q1, ref; Q2, 1.23 (0.92, 1.65); Q3, 1.63 (1.24, 2.14); Q4, 1.65 (1.24, 2.19); p trend < 0.001. A similar but statistically non-significant trend was observed across quartiles of BMI (p trend = 0.07). In summary, body size may be an independent and modifiable risk factor for developing P-HPTH in women. © 2017 American Society for Bone and Mineral Research. © 2017 American

  18. Beyond body size: muscle biochemistry and body shape explain ontogenetic variation of anti-predatory behaviour in the lizard Salvator merianae.

    Science.gov (United States)

    de Barros, Fábio Cury; de Carvalho, José Eduardo; Abe, Augusto Shinya; Kohlsdorf, Tiana

    2016-06-01

    Anti-predatory behaviour evolves under the strong action of natural selection because the success of individuals avoiding predation essentially defines their fitness. Choice of anti-predatory strategies is defined by prey characteristics as well as environmental temperature. An additional dimension often relegated in this multilevel equation is the ontogenetic component. In the tegu Salvator merianae, adults run away from predators at high temperatures but prefer fighting when it is cold, whereas juveniles exhibit the same flight strategy within a wide thermal range. Here, we integrate physiology and morphology to understand ontogenetic variation in the temperature-dependent shift of anti-predatory behaviour in these lizards. We compiled data for body shape and size, and quantified enzyme activity in hindlimb and head muscles, testing the hypothesis that morphophysiological models explain ontogenetic variation in behavioural associations. Our prediction is that juveniles exhibit body shape and muscle biochemistry that enhance flight strategies. We identified biochemical differences between muscles mainly in the LDH:CS ratio, whereby hindlimb muscles were more glycolytic than the jaw musculature. Juveniles, which often use evasive strategies to avoid predation, have more glycolytic hindlimb muscles and are much smaller when compared with adults 1-2 years old. Ontogenetic differences in body shape were identified but marginally contributed to behavioural variation between juvenile and adult tegus, and variation in anti-predatory behaviour in these lizards resides mainly in associations between body size and muscle biochemistry. Our results are discussed in the ecological context of predator avoidance by individuals differing in body size living at temperature-variable environments, where restrictions imposed by the cold could be compensated by specific phenotypes. © 2016. Published by The Company of Biologists Ltd.

  19. Estimation of body-size traits by photogrammetry in large mammals to inform conservation.

    Science.gov (United States)

    Berger, Joel

    2012-10-01

    Photography, including remote imagery and camera traps, has contributed substantially to conservation. However, the potential to use photography to understand demography and inform policy is limited. To have practical value, remote assessments must be reasonably accurate and widely deployable. Prior efforts to develop noninvasive methods of estimating trait size have been motivated by a desire to answer evolutionary questions, measure physiological growth, or, in the case of illegal trade, assess economics of horn sizes; but rarely have such methods been directed at conservation. Here I demonstrate a simple, noninvasive photographic technique and address how knowledge of values of individual-specific metrics bears on conservation policy. I used 10 years of data on juvenile moose (Alces alces) to examine whether body size and probability of survival are positively correlated in cold climates. I investigated whether the presence of mothers improved juvenile survival. The posited latter relation is relevant to policy because harvest of adult females has been permitted in some Canadian and American jurisdictions under the assumption that probability of survival of young is independent of maternal presence. The accuracy of estimates of head sizes made from photographs exceeded 98%. The estimates revealed that overwinter juvenile survival had no relation to the juvenile's estimated mass (p < 0.64) and was more strongly associated with maternal presence (p < 0.02) than winter snow depth (p < 0.18). These findings highlight the effects on survival of a social dynamic (the mother-young association) rather than body size and suggest a change in harvest policy will increase survival. Furthermore, photographic imaging of growth of individual juvenile muskoxen (Ovibos moschatus) over 3 Arctic winters revealed annual variability in size, which supports the idea that noninvasive monitoring may allow one to detect how some environmental conditions ultimately affect body growth.

  20. Copepod community growth rates in relation to body size, temperature, and food availability in the East China Sea: a test of metabolic theory of ecology

    Directory of Open Access Journals (Sweden)

    K. Y. Lin

    2013-03-01

    Full Text Available Zooplankton play an essential role in marine food webs, and understanding how community-level growth rates of zooplankton vary in the field is critical for predicting how marine ecosystem function may vary in the face of environmental changes. Here, we used the artificial cohort method to examine the effects of temperature, body size, and chlorophyll concentration (a proxy for food on weight-specific growth rates for copepod communities in the East China Sea. Specifically, we tested the hypothesis that copepod community growth rates can be described by the metabolic theory of ecology (MTE, linking spatio-temporal variation of copepod growth rate with temperature and their body size. Our results generally agree with predictions made by the MTE and demonstrate that weight-specific growth rates of copepod communities in our study area are positively related with temperature and negatively related to body size. However, the regression coefficients of body size do not approach the theoretical predictions. Furthermore, we find that the deviation from the MTE predictions may be partly attributed to the effect of food availability (which is not explicitly accounted for by the MTE. In addition, significant difference in the coefficients of temperature and body size exists among taxonomic groups. Our results suggest that considering the effects of food limitation and taxonomy is necessary to better understand copepod growth rates under in situ conditions, and such effects on the MTE-based predictions need further investigation.

  1. Intraspecific Variation in Maximum Ingested Food Size and Body Mass in Varecia rubra and Propithecus coquereli

    Directory of Open Access Journals (Sweden)

    Adam Hartstone-Rose

    2011-01-01

    Full Text Available In a recent study, we quantified the scaling of ingested food size (Vb—the maximum size at which an animal consistently ingests food whole—and found that Vb scaled isometrically between species of captive strepsirrhines. The current study examines the relationship between Vb and body size within species with a focus on the frugivorous Varecia rubra and the folivorous Propithecus coquereli. We found no overlap in Vb between the species (all V. rubra ingested larger pieces of food relative to those eaten by P. coquereli, and least-squares regression of Vb and three different measures of body mass showed no scaling relationship within each species. We believe that this lack of relationship results from the relatively narrow intraspecific body size variation and seemingly patternless individual variation in Vb within species and take this study as further evidence that general scaling questions are best examined interspecifically rather than intraspecifically.

  2. Effect of body size on accumulation and distribution of 125I in the green mussel (Perna Viridis)

    International Nuclear Information System (INIS)

    Chen Shunhua; Shi Qiong; Zhao Xiaokui

    1997-10-01

    Effect of body size on accumulation and distribution of 125 I in the green mussel (Perna Viridis), has been studied. The results showed that concentration capacity of every part in smaller mussels was higher than that in larger ones. Concentration factors of 125 I in byssus (about 0.5 x 10 3 ∼1.5 x 10 3 ), the highest in all parts of the mussels, were 30∼200 times as that in soft tissues, 200∼600 times as that in feet, 600∼1000 times as that in shells. Although wet weight of byssus was no more than 1% of whole body's wet weight, the content of 125 I accumulated in it accounted for as high as 75% of total 125 I content. The relationship between concentration factor of 125 I in byssus and whole body's wet weight (or shell length) can be described as a negative power function. (16 refs., 2 figs., 3 tabs.)

  3. Determination of size distribution function

    International Nuclear Information System (INIS)

    Teshome, A.; Spartakove, A.

    1987-05-01

    The theory of a method is outlined which gives the size distribution function (SDF) of a polydispersed system of non-interacting colloidal and microscopic spherical particles, having sizes in the range 0-10 -5 cm., from a gedanken experimental scheme. It is assumed that the SDF is differentiable and the result is obtained for rotational frequency in the order of 10 3 (sec) -1 . The method may be used independently, but is particularly useful in conjunction with an alternate method described in a preceding paper. (author). 8 refs, 2 figs

  4. Childhood Body Size and the Risk of Malignant Melanoma in Adulthood

    DEFF Research Database (Denmark)

    Meyle, Kathrine D; Gamborg, Michael; Sørensen, Thorkild I A

    2017-01-01

    years and age 13 years had a significantly increased MM risk compared with children who grew taller between those ages. Birth weight was positively associated with MM. We conclude that associations between body size and MM originate early in life and are driven largely by height and birth weight...

  5. Rates and modes of body size evolution in early carnivores and herbivores: a case study from Captorhinidae

    Directory of Open Access Journals (Sweden)

    Neil Brocklehurst

    2016-01-01

    Full Text Available Body size is an extremely important characteristic, impacting on a variety of ecological and life-history traits. It is therefore important to understand the factors which may affect its evolution, and diet has attracted much interest in this context. A recent study which examined the evolution of the earliest terrestrial herbivores in the Late Carboniferous and Early Permian concluded that in the four herbivorous clades examined there was a trend towards increased body size, and that this increase was more substantial than that observed in closely related carnivorous clades. However, this hypothesis was not based on quantitative examination, and phylogenetic comparative methods provide a more robust means of testing such hypotheses. Here, the evolution of body size within different dietary regimes is examined in Captorhinidae, the most diverse and longest lived of these earliest high fibre herbivores. Evolutionary models were fit to their phylogeny to test for variation in rate and mode of evolution between the carnivorous and herbivorous members of this clade, and an analysis of rate variation throughout the tree was carried out. Estimates of ancestral body sizes were calculated in order to compare the rates and direction of evolution of lineages with different dietary regimes. Support for the idea that the high fibre herbivores within captorhinids are being drawn to a higher adaptive peak in body size than the carnivorous members of this clade is weak. A shift in rates of body size evolution is identified, but this does not coincide with the evolution of high-fibre herbivory, instead occurring earlier in time and at a more basal node. Herbivorous lineages which show an increase in size are not found to evolve at a faster rate than those which show a decrease; in fact, it is those which experience a size decrease which evolve at higher rates. It is possible the shift in rates of evolution is related to the improved food processing ability of

  6. Nasonia Parasitic Wasps Escape from Haller's Rule by Diphasic, Partially Isometric Brain-Body Size Scaling and Selective Neuropil Adaptations

    NARCIS (Netherlands)

    Groothuis, Jitte; Smid, Hans M.

    2017-01-01

    Haller's rule states that brains scale allometrically with body size in all animals, meaning that relative brain size increases with decreasing body size. This rule applies both on inter- and intraspecific comparisons. Only 1 species, the extremely small parasitic wasp Trichogramma evanescens, is

  7. Spatial and body-size dependent response of marine pelagic communities to projected global climate change.

    Science.gov (United States)

    Lefort, Stelly; Aumont, Olivier; Bopp, Laurent; Arsouze, Thomas; Gehlen, Marion; Maury, Olivier

    2015-01-01

    Temperature, oxygen, and food availability directly affect marine life. Climate models project a global warming of the ocean's surface (~+3 °C), a de-oxygenation of the ocean's interior (~-3%) and a decrease in total marine net primary production (~-8%) under the 'business as usual' climate change scenario (RCP8.5). We estimated the effects of these changes on biological communities using a coupled biogeochemical (PISCES)--ecosystems (APECOSM) model forced by the physical outputs of the last generation of the IPSL-CM Earth System Model. The APECOSM model is a size-structured bio-energetic model that simulates the 3D dynamical distributions of three interactive pelagic communities (epipelagic, mesopelagic, and migratory) under the effects of multiple environmental factors. The PISCES-APECOSM model ran from 1850 to 2100 under historical forcing followed by RCP8.5. Our RCP8.5 simulation highlights significant changes in the spatial distribution, biomass, and maximum body-size of the simulated pelagic communities. Biomass and maximum body-size increase at high latitude over the course of the century, reflecting the capacity of marine organisms to respond to new suitable environment. At low- and midlatitude, biomass and maximum body-size strongly decrease. In those regions, large organisms cannot maintain their high metabolic needs because of limited and declining food availability. This resource reduction enhances the competition and modifies the biomass distribution among and within the three communities: the proportion of small organisms increases in the three communities and the migrant community that initially comprised a higher proportion of small organisms is favored. The greater resilience of small body-size organisms resides in their capacity to fulfill their metabolic needs under reduced energy supply and is further favored by the release of predation pressure due to the decline of large organisms. These results suggest that small body-size organisms might be

  8. Speciation in little: the role of range and body size in the diversification of Malagasy mantellid frogs

    Directory of Open Access Journals (Sweden)

    Vences Miguel

    2011-07-01

    Full Text Available Abstract Background The rate and mode of lineage diversification might be shaped by clade-specific traits. In Madagascar, many groups of organisms are characterized by tiny distribution ranges and small body sizes, and this high degree of microendemism and miniaturization parallels a high species diversity in some of these groups. We here investigate the geographic patterns characterizing the radiation of the frog family Mantellidae that is virtually endemic to Madagascar. We integrate a newly reconstructed near-complete species-level timetree of the Mantellidae with georeferenced distribution records and maximum male body size data to infer the influence of these life-history traits on each other and on mantellid diversification. Results We reconstructed a molecular phylogeny based on nuclear and mitochondrial DNA for 257 species and candidate species of the mantellid frog radiation. Based on this phylogeny we identified 53 well-supported pairs of sister species that we used for phylogenetic comparative analyses, along with whole tree-based phylogenetic comparative methods. Sister species within the Mantellidae diverged at 0.2-14.4 million years ago and more recently diverged sister species had geographical range centroids more proximate to each other, independently of their current sympatric or allopatric occurrence. The largest number of sister species pairs had non-overlapping ranges, but several examples of young microendemic sister species occurring in full sympatry suggest the possibility of non-allopatric speciation. Range sizes of species included in the sister species comparisons increased with evolutionary age, as did range size differences between sister species, which rejects peripatric speciation. For the majority of mantellid sister species and the whole mantellid radiation, range and body sizes were associated with each other and small body sizes were linked to higher mitochondrial nucleotide substitution rates and higher clade

  9. Milk lacking α-casein leads to permanent reduction in body size in mice.

    Directory of Open Access Journals (Sweden)

    Andreas F Kolb

    Full Text Available The major physiological function of milk is the transport of amino acids, carbohydrates, lipids and minerals to mammalian offspring. Caseins, the major milk proteins, are secreted in the form of a micelle consisting of protein and calcium-phosphate.We have analysed the role of the milk protein α-casein by inactivating the corresponding gene in mice. Absence of α-casein protein significantly curtails secretion of other milk proteins and calcium-phosphate, suggesting a role for α-casein in the establishment of casein micelles. In contrast, secretion of albumin, which is not synthesized in the mammary epithelium, into milk is not reduced. The absence of α-casein also significantly inhibits transcription of the other casein genes. α-Casein deficiency severely delays pup growth during lactation and results in a life-long body size reduction compared to control animals, but has only transient effects on physical and behavioural development of the pups. The data support a critical role for α-casein in casein micelle assembly. The results also confirm lactation as a critical window of metabolic programming and suggest milk protein concentration as a decisive factor in determining adult body weight.

  10. Milk Lacking α-Casein Leads to Permanent Reduction in Body Size in Mice

    Science.gov (United States)

    Kolb, Andreas F.; Huber, Reinhard C.; Lillico, Simon G.; Carlisle, Ailsa; Robinson, Claire J.; Neil, Claire; Petrie, Linda; Sorensen, Dorte B.; Olsson, I. Anna S.; Whitelaw, C. Bruce A.

    2011-01-01

    The major physiological function of milk is the transport of amino acids, carbohydrates, lipids and minerals to mammalian offspring. Caseins, the major milk proteins, are secreted in the form of a micelle consisting of protein and calcium-phosphate. We have analysed the role of the milk protein α-casein by inactivating the corresponding gene in mice. Absence of α-casein protein significantly curtails secretion of other milk proteins and calcium-phosphate, suggesting a role for α-casein in the establishment of casein micelles. In contrast, secretion of albumin, which is not synthesized in the mammary epithelium, into milk is not reduced. The absence of α-casein also significantly inhibits transcription of the other casein genes. α-Casein deficiency severely delays pup growth during lactation and results in a life-long body size reduction compared to control animals, but has only transient effects on physical and behavioural development of the pups. The data support a critical role for α-casein in casein micelle assembly. The results also confirm lactation as a critical window of metabolic programming and suggest milk protein concentration as a decisive factor in determining adult body weight. PMID:21789179

  11. Body-size trends of the extinct giant shark Carcharocles megalodon: a deep-time perspective on marine apex predators.

    Science.gov (United States)

    Pimiento, Catalina; Balk, Meghan A

    2015-06-01

    The extinct shark Carcharocles megalodon is one of the largest marine apex predators ever to exist. Nonetheless, little is known about its body-size variations through time and space. Here, we studied the body-size trends of C. megalodon through its temporal and geographic range to better understand its ecology and evolution. Given that this species was the last of the megatooth lineage, a group of species that shows a purported size increase through time, we hypothesized that C. megalodon also displayed this trend, increasing in size over time and reaching its largest size prior to extinction. We found that C. megalodon body-size distribution was left-skewed (suggesting a long-term selective pressure favoring larger individuals), and presented significant geographic variation (possibly as a result of the heterogeneous ecological constraints of this cosmopolitan species) over geologic time. Finally, we found that stasis was the general mode of size evolution of C. megalodon (i.e., no net changes over time), contrasting with the trends of the megatooth lineage and our hypothesis. Given that C. megalodon is a relatively long-lived species with a widely distributed fossil record, we further used this study system to provide a deep-time perspective to the understanding of the body-size trends of marine apex predators. For instance, our results suggest that (1) a selective pressure in predatory sharks for consuming a broader range of prey may favor larger individuals and produce left-skewed distributions on a geologic time scale; (2) body-size variations in cosmopolitan apex marine predators may depend on their interactions with geographically discrete communities; and (3) the inherent characteristics of shark species can produce stable sizes over geologic time, regardless of the size trends of their lineages.

  12. Choosing representative body sizes for reference adults and children

    International Nuclear Information System (INIS)

    Cristy, M.

    1992-01-01

    In 1975 the International Commission on Radiological Protection published a report on Reference Man (ICRP Publication 23), and a task group of the ICRP is now revising that report. Currently 'Reference Man [adult male] is defined as being between 20-30 years of age, weighing 70 kg, is 170 cm in height, is a Caucasian and is a Western European or North American in habitat and custom' (ICRP 23, p. 4). A reference adult female (58 kg, 160 cm) was also defined and data on the fetus and children were given, but with less detail and fewer specific reference values because the focus of the ICRP at that time was on young male radiation workers. The 70-kg Reference Man (earlier called Standard Man) has been used in radiation protection for 40 years, including the dosimetric schema for nuclear medicine, and this 70-kg reference has been used since at least the 1920's in physiological models. As is well known, humans in most parts of the world have increased in size (height and weight) since this standard was first adopted. Taking modern European populations as a reference and expanding the age range to 20-50 years, the author now suggests 176 cm height and 73-75 kg weight for adult males and 163 cm and about 60 kg for adult females would be more appropriate. The change in height is particularly important because many anatomical and physiological parameters - e.g., lean body mass, skeletal weight, total body water, blood volume, respiratory volumes - are correlated more closely with height than with weight. The difference in lean body mass between Asian and Caucasian persons, for example, is largely or wholly due to the difference in body height. Many equations for mean body water and other whole-body measures use body height as the only or the most important parameter, and so it is important that reference body height be chosen well

  13. Genetics of human body size and shape: body proportions and indices.

    Science.gov (United States)

    Livshits, Gregory; Roset, A; Yakovenko, K; Trofimov, S; Kobyliansky, E

    2002-01-01

    The study of the genetic component in morphological variables such as body height and weight, head and chest circumference, etc. has a rather long history. However, only a few studies investigated body proportions and configuration. The major aim of the present study was to evaluate the extent of the possible genetic effects on the inter-individual variation of a number of body configuration indices amenable to clear functional interpretation. Two ethnically different pedigree samples were used in the study: (1) Turkmenians (805 individuals) from Central Asia, and (2) Chuvasha (732 individuals) from the Volga riverside, Russian Federation. To achieve the aim of the present study we proposed three new indices, which were subjected to a statistical-genetic analysis using modified version of "FISHER" software. The proposed indices were: (1) an integral index of torso volume (IND#1), an index reflecting a predisposition of body proportions to maintain a balance in a vertical position (IND#2), and an index of skeletal extremities volume (IND#3). Additionally, the first two principal factors (PF1 and PF2) obtained on 19 measurements of body length and breadth were subjected to genetic analysis. Variance decomposition analysis that simultaneously assess the contribution of gender, age, additive genetic effects and effects of environment shared by the nuclear family members, was applied to fit variation of the above three indices, and PF1 and PF2. The raw familial correlation of all study traits and in both samples showed: (1) all marital correlations did not differ significantly from zero; (2) parent-offspring and sibling correlations were all positive and statistically significant. The parameter estimates obtained in variance analyses showed that from 40% to 75% of inter-individual variation of the studied traits (adjusted for age and sex) were attributable to genetic effects. For PF1 and PF2 in both samples, and for IND#2 (in Chuvasha pedigrees), significant common sib

  14. Tactic changes in dusky frillgoby Bathygobius fuscus sneaker males: effects of body size and nest availability.

    Science.gov (United States)

    Takegaki, T; Kaneko, T; Matsumoto, Y

    2013-02-01

    Field and laboratory studies were conducted to examine the effects of nest availability and body size on changes in male mating tactics from sneaking to nest-holding in the dusky frillgoby Bathygobius fuscus. In the field, the body size of nest-holding males decreased from early to mid-breeding season, suggesting the possibility of a change in the tactics of sneaker males to nest-holding. Many sneaker males did not use vacant spawning nests even when size-matched nests were available, but they continued to reproduce as sneakers. Similarly, in aquarium experiments with available vacant nests, some sneaker males became nest-holders irrespective of their body size, but some did not. These results showed that nest availability is not a limiting factor for changes in tactics by sneaker males in this species. Because tactic-unchanged sneaker males were co-housed with larger nest-holding males in the tanks, the body size of nearby nest-holding males may have affected the decision to change tactics for sneaker males. Moreover, smaller individuals among tactic-changed males tended to spend more time until spawning, probably because they had relatively larger costs and smaller benefits of reproduction as nest-holding males compared to larger males. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  15. Functional integral representation of the nuclear many-body grand partition function

    International Nuclear Information System (INIS)

    Kerman, A.K.; Troudet, T.

    1984-01-01

    A local functional integral formulation of the nuclear many-body problem is proposed which is a generalization of the method previously developed. Its most interesting feature is that it allows an expansion of the many-body evolution operator around any arbitrary mean-field which takes into account the pairing correlations between the nucleons. This is explicitly illustrated for the nuclear many-body grand partition function for which special attention is paid to the static temperature-dependent Hartree-Fock-Bogolyubov (H.F.B.) approximation. Indeed, the temperature-dependent H.F.B. configuration appears to be the optimal choice from a variational point of view among all the possible independent quasi-particle motion approximations. An analytic approximation of the energy level density rho (E,A) is given using explicitly the arbitrariness in the choice of the mean-field and a possible numerical application is proposed. Finally, a new compact formulation of our functional integral that might be useful for future Monte Carlo calculations is proposed

  16. Thermodynamical and Green function many-body Wick theorems

    International Nuclear Information System (INIS)

    Westwanski, B.

    1987-01-01

    The thermodynamical and Green function many-body reduction theorems of Wick type are proved for the arbitrary mixtures of the fermion, boson and spin systems. ''Many-body'' means that the operators used are the products of the arbitrary number of one-body standard basis operators [of the fermion or (and) spin types] with different site (wave vector) indices, but having the same ''time'' (in the interaction representation). The method of proving is based on'' 1) the first-order differential equation of Schwinger type for: 1a) anti T-product of operators; 1b) its average value; 2) KMS boundary conditions for this average. It is shown that the fermion, boson and spin systems can be unified in the many-body formulation (bosonification of the fermion systems). It is impossible in the one-body approach. Both of the many-body versions of the Wick theorem have the recurrent feature: nth order moment diagrams for the free energy or Green functions can be expressed by the (n-1)th order ones. This property corresponds to the automatic realization of: (i) summations over Bose-Einstein or (and) Fermi-Dirac frequencies; (ii) elimination of Bose-Einstein or (and) Fermi-Dirac distributions. The procedures (i) and (ii), being the results of using the Green function one-body reduction theorem, have constituted the significant difficulty up to now in the treatment of quantum systems. (orig.)

  17. Geographic body size and shape variation in a mainland anolis (Squamata: Dactyloidae) from northwestern South America (Colombia)

    International Nuclear Information System (INIS)

    Calderon Espinosa, Martha L; Barragan Contreras, Leidy Alejandra

    2014-01-01

    Anolis auratus is a widely distributed species, from Costa Rica in Central America, through northern South America, including Colombia, Venezuela, northern Brazil, Surinam and the Guyanas. In Colombia, its widespread distribution across different life zones suggests that these lizards occupy different environments and exhibit different microhabitat use in different geographic areas. On the other hand, some observations suggest that this species prefers open areas, selecting grasslands over brushy areas, and thus, an alternative hypothesis is that microhabitat use is similar among different populations. In Anolis, body variables related to locomotion (body size and shape) defines structural microhabitat use, so two distinct patterns could be expected in this species: Conservative or highly variable body size and shape throughout the species distribution. To test these predictions, we characterized geographic variation in morphometric traits of this species in Colombia. Females and males were similar in body size, but exhibited differences in some variables related to body shape. These characteristics also varied among males and females from different regions, suggesting heterogeneous use of structural microhabitat, between sexes and among populations. As an alternative, phylogenetic divergence among populations could also account for the observed differences. Absence of ecological and phylogenetic data limits our ability to identify the underlying causes of this pattern. However, we provide a general framework to explore hypotheses about evolution of body size and shape in this species.

  18. Secular trends of body sizes in Korean children and adolescents: from 1965 to 2010

    Directory of Open Access Journals (Sweden)

    Jin Soo Moon

    2011-11-01

    Full Text Available An anthropometric survey is one of the most important approaches to use when evaluating the health status of children. Secular trends in body sizes, such as height, weight, head circumference, chest circumference, and body mass index showed significant changes over 40 years in Korea. A series of periodic surveys were conducted in 1967, 1975, 1985, 1997, and 2005 by the Korean Pediatric Society and Ministry of Health and Welfare. The quality of data from school health examinations and the Korea National Health and Nutrition Examination Survey has improved, so we can use them now as resources for anthropometric analysis. The final height differences between 1965 and 1997 were 4.5 cm both in boys (168.9 cm in 1965; 173.4 cm in 1997 and girls (155.9 cm in 1965; 160.4 cm in 1997. The differences between 1997 and 2005 were 0.9 cm in boys (174.3cm in 2005 and 0.8 cm in girls (161.2 cm in 2005. There was no difference in final height measurements between 2005 and 2010. An increase in body size at earlier teen ages was pronounced during these decades compared to the previous generation; however, little change has been identified more recently. Body size has been increasing, and obesity has become more prevalent. Systems that gather data should be updated in order to cope with these secular trends. In an upcoming era of secular trends that would be in a slow transition, several surveys that include body measurements should be prepared to meet future needs.

  19. Inter-assemblage facilitation: the functional diversity of cavity-producing beetles drives the size diversity of cavity-nesting bees.

    Science.gov (United States)

    Sydenham, Markus A K; Häusler, Lise D; Moe, Stein R; Eldegard, Katrine

    2016-01-01

    Inter-specific interactions are important drivers and maintainers of biodiversity. Compared to trophic and competitive interactions, the role of non-trophic facilitation among species has received less attention. Cavity-nesting bees nest in old beetle borings in dead wood, with restricted diameters corresponding to the body size of the bee species. The aim of this study was to test the hypothesis that the functional diversity of cavity-producing wood boring beetles - in terms of cavity diameters - drives the size diversity of cavity-nesting bees. The invertebrate communities were sampled in 30 sites, located in forested landscapes along an elevational gradient. We regressed the species richness and abundance of cavity nesting bees against the species richness and abundance of wood boring beetles, non-wood boring beetles and elevation. The proportion of cavity nesting bees in bee species assemblage was regressed against the species richness and abundance of wood boring beetles. We also tested the relationships between the size diversity of cavity nesting bees and wood boring beetles. The species richness and abundance of cavity nesting bees increased with the species richness and abundance of wood boring beetles. No such relationship was found for non-wood boring beetles. The abundance of wood boring beetles was also related to an increased proportion of cavity nesting bee individuals. Moreover, the size diversity of cavity-nesting bees increased with the functional diversity of wood boring beetles. Specifically, the mean and dispersion of bee body sizes increased with the functional dispersion of large wood boring beetles. The positive relationships between cavity producing bees and cavity nesting bees suggest that non-trophic facilitative interactions between species assemblages play important roles in organizing bee species assemblages. Considering a community-wide approach may therefore be required if we are to successfully understand and conserve wild bee

  20. The influence of tested body size upon longitudinal ultrasonic pulse velocity

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2001-01-01

    Low ultrasonic frequencies are used in nondestructive testing of heterogeneous materials,such as concrete,rocks and timber.When frequencies are low enough,size and shape of tested bodies may influence measured longitudinal pulse velocities(geometric dispersion).A simplified mathematical model is developed from known experimental and theoretical results obtained for elastic wave propagation in rods of uniform circular cross section.Wave propagation is described by a spatial averaged dilatational field in an approach which is named quasi fluid.A formula is obtained which relates group velocity with an effective lateral size of the body,with transducers a frequency,with a non-dimensional parameter and with asymptotic P-wave velocity.In principle it can be applied to bars of any uniform cross section.The limitations of this formula are discussed in relation to path length,threshold of detection,patterns of radiation and reception and other variables.A more general formula is proposed.Practical application of this formula is briefly exemplified using some experimental data obtained by the author.The problem of longitudinal pulse propagation in reinforcing steel bars embedded in concrete is briefly considered

  1. The influence of body size on adult skeletal age estimation methods.

    Science.gov (United States)

    Merritt, Catherine E

    2015-01-01

    Accurate age estimations are essential to archaeological and forensic analyses. However, reliability for adult skeletal age estimations is poor, especially for individuals over the age of 40 years. This is the first study to show that body size influences skeletal age estimation. The İşcan et al., Lovejoy et al., Buckberry and Chamberlain, and Suchey-Brooks age methods were tested on 764 adult skeletons from the Hamann-Todd and William Bass Collections. Statures ranged from 1.30 to 1.93 m and body masses ranged from 24.0 to 99.8 kg. Transition analysis was used to evaluate the differences in the age estimations. For all four methods, the smallest individuals have the lowest ages at transition and the largest individuals have the highest ages at transition. Short and light individuals are consistently underaged, while tall and heavy individuals are consistently overaged. When femoral length and femoral head diameter are compared with the log-age model, results show the same trend as the known stature and body mass measurements. The skeletal remains of underweight individuals have fewer age markers while those of obese individuals have increased surface degeneration and osteophytic lipping. Tissue type and mechanical loading have been shown to affect bone turnover rates, and may explain the differing patterns of skeletal aging. From an archaeological perspective, the underaging of light, short individuals suggests the need to revisit the current research consensus on the young mortality rates of past populations. From a forensic perspective, understanding the influence of body size will impact efforts to identify victims of mass disasters, genocides, and homicides. © 2014 Wiley Periodicals, Inc.

  2. INITIAL PLANETESIMAL SIZES AND THE SIZE DISTRIBUTION OF SMALL KUIPER BELT OBJECTS

    International Nuclear Information System (INIS)

    Schlichting, Hilke E.; Fuentes, Cesar I.; Trilling, David E.

    2013-01-01

    The Kuiper Belt is a remnant from the early solar system and its size distribution contains many important constraints that can be used to test models of planet formation and collisional evolution. We show, by comparing observations with theoretical models, that the observed Kuiper Belt size distribution is well matched by coagulation models, which start with an initial planetesimal population with radii of about 1 km, and subsequent collisional evolution. We find that the observed size distribution above R ∼ 30 km is primordial, i.e., it has not been modified by collisional evolution over the age of the solar system, and that the size distribution below R ∼ 30 km has been modified by collisions and that its slope is well matched by collisional evolution models that use published strength laws. We investigate in detail the resulting size distribution of bodies ranging from 0.01 km to 30 km and find that its slope changes several times as a function of radius before approaching the expected value for an equilibrium collisional cascade of material strength dominated bodies for R ∼< 0.1 km. Compared to a single power-law size distribution that would span the whole range from 0.01 km to 30 km, we find in general a strong deficit of bodies around R ∼ 10 km and a strong excess of bodies around 2 km in radius. This deficit and excess of bodies are caused by the planetesimal size distribution left over from the runaway growth phase, which left most of the initial mass in small planetesimals while only a small fraction of the total mass is converted into large protoplanets. This excess mass in small planetesimals leaves a permanent signature in the size distribution of small bodies that is not erased after 4.5 Gyr of collisional evolution. Observations of the small Kuiper Belt Object (KBO) size distribution can therefore test if large KBOs grew as a result of runaway growth and constrained the initial planetesimal sizes. We find that results from recent KBO

  3. Vertebral Adaptations to Large Body Size in Theropod Dinosaurs.

    Directory of Open Access Journals (Sweden)

    John P Wilson

    Full Text Available Rugose projections on the anterior and posterior aspects of vertebral neural spines appear throughout Amniota and result from the mineralization of the supraspinous and interspinous ligaments via metaplasia, the process of permanent tissue-type transformation. In mammals, this metaplasia is generally pathological or stress induced, but is a normal part of development in some clades of birds. Such structures, though phylogenetically sporadic, appear throughout the fossil record of non-avian theropod dinosaurs, yet their physiological and adaptive significance has remained unexamined. Here we show novel histologic and phylogenetic evidence that neural spine projections were a physiological response to biomechanical stress in large-bodied theropod species. Metaplastic projections also appear to vary between immature and mature individuals of the same species, with immature animals either lacking them or exhibiting smaller projections, supporting the hypothesis that these structures develop through ontogeny as a result of increasing bending stress subjected to the spinal column. Metaplastic mineralization of spinal ligaments would likely affect the flexibility of the spinal column, increasing passive support for body weight. A stiff spinal column would also provide biomechanical support for the primary hip flexors and, therefore, may have played a role in locomotor efficiency and mobility in large-bodied species. This new association of interspinal ligament metaplasia in Theropoda with large body size contributes additional insight to our understanding of the diverse biomechanical coping mechanisms developed throughout Dinosauria, and stresses the significance of phylogenetic methods when testing for biological trends, evolutionary or not.

  4. Vertebral Adaptations to Large Body Size in Theropod Dinosaurs.

    Science.gov (United States)

    Wilson, John P; Woodruff, D Cary; Gardner, Jacob D; Flora, Holley M; Horner, John R; Organ, Chris L

    2016-01-01

    Rugose projections on the anterior and posterior aspects of vertebral neural spines appear throughout Amniota and result from the mineralization of the supraspinous and interspinous ligaments via metaplasia, the process of permanent tissue-type transformation. In mammals, this metaplasia is generally pathological or stress induced, but is a normal part of development in some clades of birds. Such structures, though phylogenetically sporadic, appear throughout the fossil record of non-avian theropod dinosaurs, yet their physiological and adaptive significance has remained unexamined. Here we show novel histologic and phylogenetic evidence that neural spine projections were a physiological response to biomechanical stress in large-bodied theropod species. Metaplastic projections also appear to vary between immature and mature individuals of the same species, with immature animals either lacking them or exhibiting smaller projections, supporting the hypothesis that these structures develop through ontogeny as a result of increasing bending stress subjected to the spinal column. Metaplastic mineralization of spinal ligaments would likely affect the flexibility of the spinal column, increasing passive support for body weight. A stiff spinal column would also provide biomechanical support for the primary hip flexors and, therefore, may have played a role in locomotor efficiency and mobility in large-bodied species. This new association of interspinal ligament metaplasia in Theropoda with large body size contributes additional insight to our understanding of the diverse biomechanical coping mechanisms developed throughout Dinosauria, and stresses the significance of phylogenetic methods when testing for biological trends, evolutionary or not.

  5. Ultrasonography assessment of renal size and its correlation with body mass index in adults without known renal disease

    International Nuclear Information System (INIS)

    Raza, M.; Hameed, A.; Khan, M.I.

    2012-01-01

    Many conditions affect renal size. To evaluate abnormalities in renal size, knowledge of standardised values for normal renal dimensions is essential as it shows variability in the values of normal renal size depending on body size, age and ethnicity. Ultrasound, being an easily available, non-invasive, safe and less expensive modality, is widely used for evaluation of renal dimensions and repeated follow-ups. The objectives of this study were to determine renal size by ultrasound in adults without any known renal disease, and to determine the relationship of renal size with body mass index. Methods: Study was conducted in the Department of Diagnostic Radiology, Shifa International Hospital and PIMS Islamabad. Renal size was assessed by ultrasound in 4,035 adult subjects with normal serum creatinine and without any known renal disease, between November 2002 and December 2010. Renal length, width, thickness and volume were obtained and mean renal length and volume were correlated with body mass index and other factors like age, side, gender, weight and height of the subjects. Results: Mean renal length on right side was 101.6+-8.9 mm, renal width 42.7+-7.1 mm, and parenchymal thickness 14.4+-2.9 mm. On left side, mean renal length was 102.7+-9.2 mm, width 47.6+-7.0 mm, and parenchymal thickness 15.1+-3.1 mm. Mean renal volume on right was 99.8+-37.2 cm/sup 3/ and on left was 124.4+-41.3 cm/sup 3/. Left renal size was significantly larger than right in both genders. Relationship of mean renal length was significant when correlated with age, side, gender, height and weight, and body mass index. Renal volumes also showed a similar relationship with side, gender, height and weight, and body mass index; but with age such a relationship was seen only for left kidney. Conclusion: Pakistani population has mean renal size smaller than reference values available in international literature. Renal length and volume have a direct relationship with body mass index. Mean renal

  6. Effect of gender and lean body mass on kidney size in healthy 10-year-old children

    DEFF Research Database (Denmark)

    Schmidt, I. M.; Mølgaard, C.; Main, K. M.

    2001-01-01

    predictor of kidney volume was lean body mass, overruling height, weight, and surface area. When total kidney volume was related to lean body mass as a ratio, the gender difference in kidney size was no longer significant. A strong negative correlation was found between fat body mass and kidney volume...

  7. Patient size and x-ray transmission in body CT.

    Science.gov (United States)

    Ogden, Kent; Huda, Walter; Scalzetti, Ernest M; Roskopf, Marsha L

    2004-04-01

    Physical characteristics were obtained for 196 patients undergoing chest and abdomen computed tomography (CT) examinations. Computed tomography sections for these patients having no evident pathology were analyzed to determine patient dimensions (AP and lateral), together with the average attenuation coefficient. Patient weights ranged from approximately 3 kg to about 120 kg. For chest CT, the mean Hounsfield unit (HU) fell from about -120 HU for newborns to about -300 HU for adults. For abdominal CT, the mean HU for children and normal-sized adults was about 20 HU, but decreased to below -50 HU for adults weighing more than 100 kg. The effective photon energy and percent energy fluence transmitted through a given patient size and composition was calculated for representative x-ray spectra at 80, 100, 120, and 140 kV tube potentials. A 70-kg adult scanned at 120 kVp transmits 2.6% of the energy fluence for chest and 0.7% for abdomen CT examinations. Reducing the patient size to 10 kg increases transmission by an order of magnitude. For 70 kg patients, effective energies in body CT range from approximately 50 keV at 80 kVp to approximately 67 keV at 140 kVp; increasing patient size from 10 to 120 kg resulted in an increase in effective photon energy of approximately 4 keV. The x-ray transmission data and effective photon energy data can be used to determine CT image noise and image contrast, respectively, and information on patient size and composition can be used to determine patient doses.

  8. Change in body size and mortality: results from the Melbourne collaborative cohort study.

    Science.gov (United States)

    Karahalios, Amalia; Simpson, Julie A; Baglietto, Laura; MacInnis, Robert J; Hodge, Allison M; Giles, Graham G; English, Dallas R

    2014-01-01

    The association between change in weight or body mass index, and mortality is widely reported, however, both measures fail to account for fat distribution. Change in waist circumference, a measure of central adiposity, in relation to mortality has not been studied extensively. We investigated the association between mortality and changes in directly measured waist circumference, hips circumference and weight from baseline (1990-1994) to wave 2 (2003-2007) in a prospective cohort study of people aged 40-69 years at baseline. Cox regression, with age as the time metric and follow-up starting at wave 2, adjusted for confounding variables, was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for change in body size in relation to mortality from all causes, cardiovascular disease and cancer. There were 1465 deaths (109 cancer, 242 cardiovascular disease) identified during an average 7.7 years of follow-up from 21 298 participants. Compared to minimal increase in body size, loss of waist circumference (HR: 1.26; 95% CI: 1.09-1.47), weight (1.80; 1.54-2.11), or hips circumference (1.35; 1.15-1.57) were associated with an increased risk of all-cause mortality, particularly for older adults. Weight loss was associated with cardiovascular disease mortality (2.40; 1.57-3.65) but change in body size was not associated with obesity-related cancer mortality. This study confirms the association between weight loss and increased mortality from all-causes for older adults. Based on evidence from observational cohort studies, weight stability may be the recommended option for most adults, especially older adults.

  9. Physical capital and the embodied nature of income inequality: gender differences in the effect of body size on workers' incomes in Canada.

    Science.gov (United States)

    Perks, Thomas

    2012-02-01

    This study assesses the effects of body size--measured using the body mass index--on the income attainment of female and male workers in Canada. Using data from a national representative sample of Canadians, multivariate analyses show that, for female workers, the body size-income relationship is negative. However, for male workers, the body size-income relationship is positive and nonlinear. Using Bourdieu's conceptualization of physical capital, and Shilling's extension of it, it is argued that these results are suggestive of the relative importance of body size to the production and continuation of gender income inequality in Canada.

  10. Ontogenetic and evolutionary effects of predation and competition on nine-spined stickleback (Pungitius pungitius) body size.

    Science.gov (United States)

    Välimäki, Kaisa; Herczeg, Gábor

    2012-07-01

    1. Individual- and population-level variation in body size and growth often correlates with many fitness traits. Predation and food availability are expected to affect body size and growth as important agents of both natural selection and phenotypic plasticity. How differences in predation and food availability affect body size/growth during ontogeny in populations adapted to different predation and competition regimes is rarely studied. 2. Nine-spined stickleback (Pungitius pungitius) populations originating from habitats with varying levels of predation and competition are known to be locally adapted to their respective habitats in terms of body size and growth. Here, we studied how different levels of perceived predation risk and competition during ontogeny affect the reaction norms of body size and growth in (i) marine and pond populations adapted to different levels of predation and competition and (ii) different sexes. We reared nine-spined stickleback in a factorial experiment under two levels of perceived predation risk (present/absent) and competition (high/low food supply). 3. We found divergence in the reaction norms at two levels: (i) predation-adapted marine stickleback had stronger reactions to predatory cues than intraspecific competition-adapted pond stickleback, the latter being more sensitive to available food than the marine fish and (ii) females reacting more strongly to the treatments than males. 4. The repeated, habitat-dependent nature of the differences suggests that natural selection is the agent behind the observed patterns. Our results suggest that genetic adaptation to certain environmental factors also involves an increase in the range of expressible phenotypic plasticity. We found support for this phenomenon at two levels: (i) across populations driven by habitat type and (ii) within populations driven by sex. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

  11. From the Cover: Environmental and biotic controls on the evolutionary history of insect body size

    Science.gov (United States)

    Clapham, Matthew E.; Karr, Jered A.

    2012-07-01

    Giant insects, with wingspans as large as 70 cm, ruled the Carboniferous and Permian skies. Gigantism has been linked to hyperoxic conditions because oxygen concentration is a key physiological control on body size, particularly in groups like flying insects that have high metabolic oxygen demands. Here we show, using a dataset of more than 10,500 fossil insect wing lengths, that size tracked atmospheric oxygen concentrations only for the first 150 Myr of insect evolution. The data are best explained by a model relating maximum size to atmospheric environmental oxygen concentration (pO2) until the end of the Jurassic, and then at constant sizes, independent of oxygen fluctuations, during the Cretaceous and, at a smaller size, the Cenozoic. Maximum insect size decreased even as atmospheric pO2 rose in the Early Cretaceous following the evolution and radiation of early birds, particularly as birds acquired adaptations that allowed more agile flight. A further decrease in maximum size during the Cenozoic may relate to the evolution of bats, the Cretaceous mass extinction, or further specialization of flying birds. The decoupling of insect size and atmospheric pO2 coincident with the radiation of birds suggests that biotic interactions, such as predation and competition, superseded oxygen as the most important constraint on maximum body size of the largest insects.

  12. An Echocardiographic Study of Left Ventricular Size and Cardiac Function in Adolescent Females with Anorexia Nervosa.

    Science.gov (United States)

    Escudero, Carolina A; Potts, James E; Lam, Pei-Yoong; De Souza, Astrid M; Mugford, Gerald J; Sandor, George G S

    2016-01-01

    This retrospective case-control study investigated cardiac dimensions and ventricular function in female adolescents with anorexia nervosa (AN) compared with controls. Echocardiographic measurements of left ventricular (LV) dimensions, LV mass index, left atrial size and cardiac index were made. Detailed measures of systolic and diastolic ventricular function were made including tissue Doppler imaging. Patients were stratified by body mass index ≤10th percentile (AN ≤ 10th) and >10th percentile (AN > 10th). Ninety-five AN patients and 58 controls were included. AN and AN ≤ 10th groups had reduced LV dimensions, LV mass index, left atrial size and cardiac index compared with controls. There were no differences between groups in measures of systolic function. Measures of diastolic tissue Doppler imaging were decreased in AN and AN ≤ 10th. No differences in echocardiographic measurements existed between controls and AN > 10th. Female adolescents with AN have preserved systolic function and abnormalities of diastolic ventricular function. AN ≤ 10th may be a higher risk group. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.

  13. Cryptic lineage diversity, body size divergence, and sympatry in a species complex of Australian lizards (Gehyra).

    Science.gov (United States)

    Moritz, Craig C; Pratt, Renae C; Bank, Sarah; Bourke, Gayleen; Bragg, Jason G; Doughty, Paul; Keogh, J Scott; Laver, Rebecca J; Potter, Sally; Teasdale, Luisa C; Tedeschi, Leonardo G; Oliver, Paul M

    2018-01-01

    Understanding the joint evolutionary and ecological underpinnings of sympatry among close relatives remains a key challenge in biology. This problem can be addressed through joint phylogenomic and phenotypic analysis of complexes of closely related lineages within, and across, species and hence representing the speciation continuum. For a complex of tropical geckos from northern Australia-Gehyra nana and close relatives-we combine mtDNA phylogeography, exon-capture sequencing, and morphological data to resolve independently evolving lineages and infer their divergence history and patterns of morphological evolution. Gehyra nana is found to include nine divergent lineages and is paraphyletic with four other species from the Kimberley region of north-west Australia. Across these 13 taxa, 12 of which are restricted to rocky habitats, several lineages overlap geographically, including on the diverse Kimberley islands. Morphological evolution is dominated by body size shifts, and both body size and shape have evolved gradually across the group. However, larger body size shifts are observed among overlapping taxa than among closely related parapatric lineages of G. nana, and sympatric lineages are more divergent than expected at random. Whether elevated body size differences among sympatric lineages are due to ecological sorting or character displacement remains to be determined. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  14. Body size and hosts of Triatoma infestans populations affect the size of bloodmeal contents and female fecundity in rural northwestern Argentina.

    Science.gov (United States)

    Gürtler, Ricardo E; Fernández, María Del Pilar; Cecere, María Carla; Cohen, Joel E

    2017-12-01

    Human sleeping quarters (domiciles) and chicken coops are key source habitats of Triatoma infestans-the principal vector of the infection that causes Chagas disease-in rural communities in northern Argentina. Here we investigated the links among individual bug bloodmeal contents (BMC, mg), female fecundity, body length (L, mm), host blood sources and habitats. We tested whether L, habitat and host blood conferred relative fitness advantages using generalized linear mixed-effects models and a multimodel inference approach with model averaging. The data analyzed include 769 late-stage triatomines collected in 120 sites from six habitats in 87 houses in Figueroa, Santiago del Estero, during austral spring. L correlated positively with other body-size surrogates and was modified by habitat type, bug stage and recent feeding. Bugs from chicken coops were significantly larger than pig-corral and kitchen bugs. The best-fitting model of log BMC included habitat, a recent feeding, bug stage, log Lc (mean-centered log L) and all two-way interactions including log Lc. Human- and chicken-fed bugs had significantly larger BMC than bugs fed on other hosts whereas goat-fed bugs ranked last, in consistency with average blood-feeding rates. Fecundity was maximal in chicken-fed bugs from chicken coops, submaximal in human- and pig-fed bugs, and minimal in goat-fed bugs. This study is the first to reveal the allometric effects of body-size surrogates on BMC and female fecundity in a large set of triatomine populations occupying multiple habitats, and discloses the links between body size, microsite temperatures and various fitness components that affect the risks of transmission of Trypanosoma cruzi.

  15. Body size and hosts of Triatoma infestans populations affect the size of bloodmeal contents and female fecundity in rural northwestern Argentina.

    Directory of Open Access Journals (Sweden)

    Ricardo E Gürtler

    2017-12-01

    Full Text Available Human sleeping quarters (domiciles and chicken coops are key source habitats of Triatoma infestans-the principal vector of the infection that causes Chagas disease-in rural communities in northern Argentina. Here we investigated the links among individual bug bloodmeal contents (BMC, mg, female fecundity, body length (L, mm, host blood sources and habitats. We tested whether L, habitat and host blood conferred relative fitness advantages using generalized linear mixed-effects models and a multimodel inference approach with model averaging. The data analyzed include 769 late-stage triatomines collected in 120 sites from six habitats in 87 houses in Figueroa, Santiago del Estero, during austral spring. L correlated positively with other body-size surrogates and was modified by habitat type, bug stage and recent feeding. Bugs from chicken coops were significantly larger than pig-corral and kitchen bugs. The best-fitting model of log BMC included habitat, a recent feeding, bug stage, log Lc (mean-centered log L and all two-way interactions including log Lc. Human- and chicken-fed bugs had significantly larger BMC than bugs fed on other hosts whereas goat-fed bugs ranked last, in consistency with average blood-feeding rates. Fecundity was maximal in chicken-fed bugs from chicken coops, submaximal in human- and pig-fed bugs, and minimal in goat-fed bugs. This study is the first to reveal the allometric effects of body-size surrogates on BMC and female fecundity in a large set of triatomine populations occupying multiple habitats, and discloses the links between body size, microsite temperatures and various fitness components that affect the risks of transmission of Trypanosoma cruzi.

  16. Mammalian collection on Noah's Ark: the effects of beauty, brain and body size.

    Directory of Open Access Journals (Sweden)

    Daniel Frynta

    Full Text Available The importance of today's zoological gardens as the so-called "Noah's Ark" grows as the natural habitat of many species quickly diminishes. Their potential to shelter a large amount of individuals from many species gives us the opportunity to reintroduce a species that disappeared in nature. However, the selection of animals to be kept in zoos worldwide is highly selective and depends on human decisions driven by both ecological criteria such as population size or vulnerability and audience-driven criteria such as aesthetic preferences. Thus we focused our study on the most commonly kept and bred animal class, the mammals, and we asked which factors affect various aspects of the mammalian collection of zoos. We analyzed the presence/absence, population size, and frequency per species of each of the 123 mammalian families kept in the worldwide zoo collection. Our aim was to explain these data using the human-perceived attractiveness of mammalian families, their body weight, relative brain size and species richness of the family. In agreement with various previous studies, we found that the body size and the attractiveness of mammals significantly affect all studied components of the mammalian collection of zoos. There is a higher probability of the large and attractive families to be kept. Once kept, these animals are presented in larger numbers in more zoos. On the contrary, the relative mean brain size only affects the primary selection whether to keep the family or not. It does not affect the zoo population size or the number of zoos that keep the family.

  17. Professional hazards? The impact of models' body size on advertising effectiveness and women's body-focused anxiety in professions that do and do not emphasize the cultural ideal of thinness.

    Science.gov (United States)

    Dittmar, Helga; Howard, Sarah

    2004-12-01

    Previous experimental research indicates that the use of average-size women models in advertising prevents the well-documented negative effect of thin models on women's body image, while such adverts are perceived as equally effective (Halliwell & Dittmar, 2004). The current study extends this work by: (a) seeking to replicate the finding of no difference in advertising effectiveness between average-size and thin models (b) examining level of ideal-body internalization as an individual, internal factor that moderates women's vulnerability to thin media models, in the context of (c) comparing women in professions that differ radically in their focus on, and promotion of, the sociocultural ideal of thinness for women--employees in fashion advertising (n = 75) and teachers in secondary schools (n = 75). Adverts showing thin, average-size and no models were perceived as equally effective. High internalizers in both groups of women felt worse about their body image after exposure to thin models compared to other images. Profession affected responses to average-size models. Teachers reported significantly less body-focused anxiety after seeing average-size models compared to no models, while there was no difference for fashion advertisers. This suggests that women in professional environments with less focus on appearance-related ideals can experience increased body-esteem when exposed to average-size models, whereas women in appearance-focused professions report no such relief.

  18. The genetic basis of natural variation in mushroom body size in Drosophila melanogaster.

    Science.gov (United States)

    Zwarts, Liesbeth; Vanden Broeck, Lies; Cappuyns, Elisa; Ayroles, Julien F; Magwire, Michael M; Vulsteke, Veerle; Clements, Jason; Mackay, Trudy F C; Callaerts, Patrick

    2015-12-11

    Genetic variation in brain size may provide the basis for the evolution of the brain and complex behaviours. The genetic substrate and the selective pressures acting on brain size are poorly understood. Here we use the Drosophila Genetic Reference Panel to map polymorphic variants affecting natural variation in mushroom body morphology. We identify 139 genes and 39 transcription factors and confirm effects on development and adult plasticity. We show correlations between morphology and aggression, sleep and lifespan. We propose that natural variation in adult brain size is controlled by interaction of the environment with gene networks controlling development and plasticity.

  19. The extended Price equation quantifies species selection on mammalian body size across the Palaeocene/Eocene Thermal Maximum.

    Science.gov (United States)

    Rankin, Brian D; Fox, Jeremy W; Barrón-Ortiz, Christian R; Chew, Amy E; Holroyd, Patricia A; Ludtke, Joshua A; Yang, Xingkai; Theodor, Jessica M

    2015-08-07

    Species selection, covariation of species' traits with their net diversification rates, is an important component of macroevolution. Most studies have relied on indirect evidence for its operation and have not quantified its strength relative to other macroevolutionary forces. We use an extension of the Price equation to quantify the mechanisms of body size macroevolution in mammals from the latest Palaeocene and earliest Eocene of the Bighorn and Clarks Fork Basins of Wyoming. Dwarfing of mammalian taxa across the Palaeocene/Eocene Thermal Maximum (PETM), an intense, brief warming event that occurred at approximately 56 Ma, has been suggested to reflect anagenetic change and the immigration of small bodied-mammals, but might also be attributable to species selection. Using previously reconstructed ancestor-descendant relationships, we partitioned change in mean mammalian body size into three distinct mechanisms: species selection operating on resident mammals, anagenetic change within resident mammalian lineages and change due to immigrants. The remarkable decrease in mean body size across the warming event occurred through anagenetic change and immigration. Species selection also was strong across the PETM but, intriguingly, favoured larger-bodied species, implying some unknown mechanism(s) by which warming events affect macroevolution. © 2015 The Author(s).

  20. DNA methylation patterns in cord blood DNA and body size in childhood.

    Directory of Open Access Journals (Sweden)

    Caroline L Relton

    Full Text Available Epigenetic markings acquired in early life may have phenotypic consequences later in development through their role in transcriptional regulation with relevance to the developmental origins of diseases including obesity. The goal of this study was to investigate whether DNA methylation levels at birth are associated with body size later in childhood.A study design involving two birth cohorts was used to conduct transcription profiling followed by DNA methylation analysis in peripheral blood. Gene expression analysis was undertaken in 24 individuals whose biological samples and clinical data were collected at a mean ± standard deviation (SD age of 12.35 (0.95 years, the upper and lower tertiles of body mass index (BMI were compared with a mean (SD BMI difference of 9.86 (2.37 kg/m(2. This generated a panel of differentially expressed genes for DNA methylation analysis which was then undertaken in cord blood DNA in 178 individuals with body composition data prospectively collected at a mean (SD age of 9.83 (0.23 years. Twenty-nine differentially expressed genes (>1.2-fold and p<10(-4 were analysed to determine DNA methylation levels at 1-3 sites per gene. Five genes were unmethylated and DNA methylation in the remaining 24 genes was analysed using linear regression with bootstrapping. Methylation in 9 of the 24 (37.5% genes studied was associated with at least one index of body composition (BMI, fat mass, lean mass, height at age 9 years, although only one of these associations remained after correction for multiple testing (ALPL with height, p(Corrected = 0.017.DNA methylation patterns in cord blood show some association with altered gene expression, body size and composition in childhood. The observed relationship is correlative and despite suggestion of a mechanistic epigenetic link between in utero life and later phenotype, further investigation is required to establish causality.

  1. Body size, blood feeding activity, and fecundity of Psorophora howardii, Psorophora ciliata, and Psorophora ferox (Diptera: Culicidae).

    Science.gov (United States)

    Zhu, Lin; Fulcher, Ali; Hossain, Tanjim; Davidson, Claudia; Beier, John C; Xue, Rui-De

    2014-03-01

    Field-collected female Psorophora howardii (Coquillett), Psorophora ciliate (F.), and Psorophora ferox (Humboltd) mosquitoes were tested in laboratory conditions to measure body size, blood engorgement duration, bloodmeal size, fecundity, and egg morphology. Mean bloodmeal size was significantly different among the three species of mosquitoes, whereas there was no difference in blood engorgement duration. Mean body weights and wing lengths of Ps. howardii and Ps. ciliata were significantly greater than Ps.ferox. Seven days after bloodmeals, oviposition rates for Ps. howardii, Ps. ciliata, and Ps.ferox were 18.8, 56.2, and 0%, respectively. The mean number of total eggs produced per female for the three species was 59, 81, and 73, respectively. Mean egg lengths of Ps. howardii and Ps. ciliata were significantly greater than Ps.ferox, and egg diameters for each of the three species were significantly different from one another. Length per diameter ratios of Ps. howardii and Ps. ciliata were significantly smaller than Ps. ferox. Bloodmeal size was positively related to body weight, but not related to blood engorgement duration, and the total egg number was positively related to bloodmeal size.

  2. Whole-body imaging of whole-organ, subresolution, basic functional unit (BFU) perfusion characteristics

    Science.gov (United States)

    Dong, Yue; Ritman, Erik L.

    2008-08-01

    A BFU is an organ's smallest assembly of diverse cells that functions like the organ, such as the liver's hepatic lobules. There are approximately 107 BFUs in a human organ. These 100-200 μm structures are perfused by capillaries fed by a terminal arteriole (15μm diameter). BFU sizes, function and number per organ vary with disease, either by loss of BFUs and/or their decrease in function. The BFU is the upper limit of a spherical assembly of cells, immersed in a suitably nutrient medium, which can survive without its own blood supply. However, each BFU has its own blood supply to support the extra energy and/or solutes needed for providing its physiological function (e.g., contraction or secretion). A BFU function is best evaluated by its micro-perfusion, which can be readily evaluated with whole-body CT. Resolution of individual BFUs within in-situ organs, using clinical imaging devices, would require high radiation doses and/or the intolerably long scan-durations needed for suitable signal-to-noise image-data. However, it is possible to obtain a statistical description of the BFU number, size and function from wholebody CT by way of a model. In this study we demonstrate this capability by using the distribution of myocardial terminal arteriolar perfusion territories by way of a nested, multiple, regions-of-interest analysis of the heart wall imaged during transient opacification of its blood supply.

  3. Seasonal body size reductions with warming covary with major body size gradients in arthropod species

    DEFF Research Database (Denmark)

    Horne, Curtis R.; Hirst, Andrew G.; Atkinson, David

    2017-01-01

    experience different developmental conditions. Yet, unlike other size patterns, these common seasonal temperature–size gradients have never been collectively analysed. We undertake the largest analysis to date of seasonal temperature-size gradients in multivoltine arthropods, including 102 aquatic...... and terrestrial species from 71 global locations. Adult size declines in warmer seasons in 86% of the species examined. Aquatic species show approximately 2.5-fold greater reduction in size per °C of warming than terrestrial species, supporting the hypothesis that greater oxygen limitation in water than in air...

  4. Energetic tradeoffs control the size distribution of aquatic mammals

    Science.gov (United States)

    Gearty, William; McClain, Craig R.; Payne, Jonathan L.

    2018-04-01

    Four extant lineages of mammals have invaded and diversified in the water: Sirenia, Cetacea, Pinnipedia, and Lutrinae. Most of these aquatic clades are larger bodied, on average, than their closest land-dwelling relatives, but the extent to which potential ecological, biomechanical, and physiological controls contributed to this pattern remains untested quantitatively. Here, we use previously published data on the body masses of 3,859 living and 2,999 fossil mammal species to examine the evolutionary trajectories of body size in aquatic mammals through both comparative phylogenetic analysis and examination of the fossil record. Both methods indicate that the evolution of an aquatic lifestyle is driving three of the four extant aquatic mammal clades toward a size attractor at ˜500 kg. The existence of this body size attractor and the relatively rapid selection toward, and limited deviation from, this attractor rule out most hypothesized drivers of size increase. These three independent body size increases and a shared aquatic optimum size are consistent with control by differences in the scaling of energetic intake and cost functions with body size between the terrestrial and aquatic realms. Under this energetic model, thermoregulatory costs constrain minimum size, whereas limitations on feeding efficiency constrain maximum size. The optimum size occurs at an intermediate value where thermoregulatory costs are low but feeding efficiency remains high. Rather than being released from size pressures, water-dwelling mammals are driven and confined to larger body sizes by the strict energetic demands of the aquatic medium.

  5. Ethnic and Gender Differences in Ideal Body Size and Related Attitudes among Asians, Native Hawaiians, and Whites

    Science.gov (United States)

    Takishima-Lacasa, Julie Y; Latner, Janet D; Grandinetti, Andrew; Keawe‘aimoku Kaholokula, Joseph

    2014-01-01

    Often overlooked explanations for the varied obesity rates across ethno-cultural groups include differences in attitudes toward excess weight, with certain populations assumed to have larger ideal body sizes (IBS). Past studies found ethnic and gender difference in IBS across and within different groups. This study examined the effects of ethnicity and gender, and their interaction, in accounting for differences in IBS and attitudes toward those ideals. Multiple regression analyses were used to better understand the effects of ethnicity and gender in accounting for differences in perceived IBS according to ethnic-specific and Western ideals and attitudes in 1,124 people of Native Hawaiian, Filipino, Japanese, and White ancestry. The analyses controlled for socio-demographics, body mass index, health-related behaviors, and psychosocial variables. The results indicated that Native Hawaiians selected larger ethnic IBS, Filipinos selected smaller ethnic IBS, and Native Hawaiians selected slightly smaller Western IBS than other ethnic groups. Overall, males selected larger IBS compared to females. Interaction analyses indicated that the relationship between ethnic IBS and attitude toward that IBS varied as a function of ethnicity, such that Native Hawaiians who selected a larger ethnic IBS held less favorable attitudes toward that IBS. The discrepancy between Native Hawaiians' selection of larger ethnic IBS as ideal and their less positive attitude toward that selection warrants more investigation. However, it does suggest that Native Hawaiians, on a personal level, do not prefer larger body sizes, which contradicts their perceptions of social norms. These findings have important implications for obesity interventions among Native Hawaiians. PMID:25157324

  6. Ethnic and gender differences in ideal body size and related attitudes among Asians, Native Hawaiians, and Whites.

    Science.gov (United States)

    Townsend, Claire; Takishima-Lacasa, Julie Y; Latner, Janet D; Grandinetti, Andrew; Keawe'aimoku Kaholokula, Joseph

    2014-08-01

    Often overlooked explanations for the varied obesity rates across ethno-cultural groups include differences in attitudes toward excess weight, with certain populations assumed to have larger ideal body sizes (IBS). Past studies found ethnic and gender difference in IBS across and within different groups. This study examined the effects of ethnicity and gender, and their interaction, in accounting for differences in IBS and attitudes toward those ideals. Multiple regression analyses were used to better understand the effects of ethnicity and gender in accounting for differences in perceived IBS according to ethnic-specific and Western ideals and attitudes in 1,124 people of Native Hawaiian, Filipino, Japanese, and White ancestry. The analyses controlled for socio-demographics, body mass index, health-related behaviors, and psychosocial variables. The results indicated that Native Hawaiians selected larger ethnic IBS, Filipinos selected smaller ethnic IBS, and Native Hawaiians selected slightly smaller Western IBS than other ethnic groups. Overall, males selected larger IBS compared to females. Interaction analyses indicated that the relationship between ethnic IBS and attitude toward that IBS varied as a function of ethnicity, such that Native Hawaiians who selected a larger ethnic IBS held less favorable attitudes toward that IBS. The discrepancy between Native Hawaiians' selection of larger ethnic IBS as ideal and their less positive attitude toward that selection warrants more investigation. However, it does suggest that Native Hawaiians, on a personal level, do not prefer larger body sizes, which contradicts their perceptions of social norms. These findings have important implications for obesity interventions among Native Hawaiians.

  7. Plutonium fecal and urinary excretion functions: Derivation from a systematic whole-body retention function

    International Nuclear Information System (INIS)

    Sun, C.; Lee, D.

    1999-01-01

    Liver-bile secretion directly influences the content of plutonium in feces. To assess the reliability of plutonium metabolic models and to improve the accuracy of interpreting plutonium fecal data, the authors developed a compartmental model that simulates the metabolism of plutonium in humans. With this model, they can describe the transport of plutonium contaminants in the systemic organs and tissues of the body, including fecal and urine excretions, without using elaborate kinetic information. The parameter values of the models, which describe the translocation rates and recycling of plutonium in the body, can be derived from a multi-term exponential systemic function for whole-body retention. The analytical derivations and algorithms for solving translocation parameter values are established for the model and illustrated by applying them to the biokinetics and bioassay of plutonium. This study describes how to (1) design a physiological model for incorporating liver biliary secretion and for obtaining a fecal-excretion function, (2) develop an analytical solution for identifying the translocation-parameter values incorporating the recycling of plutonium in the body, and (3) derive a set of urinary and fecal excretion-functions from a published systemic whole-body retention function, generally acknowledged to be accurate, as a real and practical example

  8. The thermal environment of the nest affects body and cell size in the solitary red mason bee (Osmia bicornis L.).

    Science.gov (United States)

    Kierat, Justyna; Szentgyörgyi, Hajnalka; Czarnoleski, Marcin; Woyciechowski, Michał

    2017-08-01

    Many ectotherms grow larger at lower temperatures than at higher temperatures. This pattern, known as the temperature-size rule, is often accompanied by plastic changes in cell size, which can mechanistically explain the thermal dependence of body size. However, the theory predicts that thermal plasticity in cell size has adaptive value for ectotherms because there are different optimal cell-membrane-to-cell-volume ratios at different temperatures. At high temperatures, the demand for oxygen is high; therefore, a large membrane surface of small cells is beneficial because it allows high rates of oxygen transport into the cell. The metabolic costs of maintaining membranes become more important at low temperatures than at high temperatures, which favours large cells. In a field experiment, we manipulated the thermal conditions inside nests of the red mason bee, a solitary bee that does not regulate the temperature in its nests and whose larvae develop under ambient conditions. We assessed the effect of temperature on body mass and ommatidia size (our proxy of cell size). The body and cell sizes decreased in response to a higher mean temperature and greater temperature fluctuations. This finding is in accordance with predictions of the temperature-size rule and optimal cell size theory and suggests that both the mean temperature and the magnitude of temperature fluctuations are important for determining body and cell sizes. Additionally, we observed that males of the red mason bee tend to have larger ommatidia in relation to their body mass than females, which might play an important role during mating flight. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Endothermy in African platypleurine cicadas: the influence of body size and habitat (Hemiptera: Cicadidae).

    Science.gov (United States)

    Sanborn, Allen F; Villet, Martin H; Phillips, Polly K

    2004-01-01

    The platypleurine cicadas have a wide distribution across Africa and southern Asia. We investigate endothermy as a thermoregulatory strategy in 11 South African species from five genera, with comparisons to the lone ectothermic platypleurine we found, in an attempt to ascertain any influence that habitat and/or body size have on the expression of endothermy in the platypleurine cicadas. Field measurements of body temperature (T(b)) show that these animals regulate T(b) through endogenous heat production. Heat production in the laboratory elevated T(b) to the same range as in animals active in the field. Maximum T(b) measured during calling activity when there was no access to solar radiation ranged from 13.2 degrees to 22.3 degrees C above ambient temperature in the five species measured. The mean T(b) during activity without access to solar radiation did not differ from the mean T(b) during diurnal activity. All platypleurines exhibit a unique behavior for cicadas while warming endogenously, a temperature-dependent telescoping pulsation of the abdomen that probably functions in ventilation. Platypleurines generally call from trunks and branches within the canopy and appear to rely on endothermy even when the sun is available to elevate T(b), in contrast to the facultative endothermy exhibited by New World endothermic species. The two exceptions to this generalization we found within the platypleurines are Platypleura wahlbergi and Albanycada albigera, which were the smallest species studied. The small size of P. wahlbergi appears to have altered their thermoregulatory strategy to one of facultative endothermy, whereby they use the sun when it is available to facilitate increases in T(b). Albanycada albigera is the only ectothermic platypleurine we found. The habitat and host plant association of A. albigera appear to have influenced the choice of ectothermy as a thermoregulatory strategy, as the species possesses the metabolic machinery to elevate to the T

  10. Effect of size and composition of the body on absolute measurement of calcium in vivo

    International Nuclear Information System (INIS)

    Spinks, T.J.

    1979-01-01

    The effect of size and composition of the body on the measurement of total calcium in absolute units by neutron activation analysis is described. The neutron beam, produced from a cyclotron, was of mean energy 7.5 MeV. Counting of the activities induced in a patient was carried out with a multidetector whole body counter. Calibration of the system was achieved by using two phantoms of different sizes containing known quantities of calcium. The dimensions of various phantom sections were varied to determine the effect on efficiency of activation, an approximately linear relationship with body thickness being found. The influence of body habitus on counting efficiency was assessed by counting different patients who had been given known quantities of 42 K. The effects of (a) the non-uniform distribution of calcium and (b) the variation in density of different tissues on both activation and counting efficiency are discussed. It is estimated that the 68% confidence limits on the measurement of 49 Ca count rate per unit neutron fluence is +- 3.0% and on the measurement of calcium in grams +- 8.2%. (author)

  11. Body size and allometric shape variation in the molly Poecilia vivipara along a gradient of salinity and predation.

    Science.gov (United States)

    Araújo, Márcio S; Perez, S Ivan; Magazoni, Maria Julia C; Petry, Ana C

    2014-12-04

    Phenotypic diversity among populations may result from divergent natural selection acting directly on traits or via correlated responses to changes in other traits. One of the most frequent patterns of correlated response is the proportional change in the dimensions of anatomical traits associated with changes in growth or absolute size, known as allometry. Livebearing fishes subject to predation gradients have been shown to repeatedly evolve larger caudal peduncles and smaller cranial regions under high predation regimes. Poecilia vivipara is a livebearing fish commonly found in coastal lagoons in the north of the state of Rio de Janeiro, Brazil. Similar to what is observed in other predation gradients, lagoons inhabited by P. vivipara vary in the presence of piscivorous fishes; contrary to other poeciliid systems, populations of P. vivipara vary greatly in body size, which opens the possibility of strong allometric effects on shape variation. Here we investigated body shape diversification among six populations of P. vivipara along a predation gradient and its relationship with allometric trajectories within and among populations. We found substantial body size variation and correlated shape changes among populations. Multivariate regression analysis showed that size variation among populations accounted for 66% of shape variation in females and 38% in males, suggesting that size is the most important dimension underlying shape variation among populations of P. vivipara in this system. Changes in the relative sizes of the caudal peduncle and cranial regions were only partly in line with predictions from divergent natural selection associated with predation regime. Our results suggest the possibility that adaptive shape variation among populations has been partly constrained by allometry in P. vivipara. Processes governing body size changes are therefore important in the diversification of this species. We conclude that in species characterized by substantial

  12. Body size distributions of the pale grass blue butterfly in Japan: Size rules and the status of the Fukushima population

    Science.gov (United States)

    Taira, Wataru; Iwasaki, Mayo; Otaki, Joji M.

    2015-01-01

    The body size of the pale grass blue butterfly, Zizeeria maha, has been used as an environmental indicator of radioactive pollution caused by the Fukushima nuclear accident. However, geographical and temporal size distributions in Japan and temperature effects on size have not been established in this species. Here, we examined the geographical, temporal, and temperature-dependent changes of the forewing size of Z. maha argia in Japan. Butterflies collected in 2012 and 2013 from multiple prefectures throughout Japan demonstrated an inverse relationship of latitude and forewing size, which is the reverse of Bergmann’s cline. The Fukushima population was significantly larger than the Aomori and Miyagi populations and exhibited no difference from most of the other prefectural populations. When monitored at a single geographic locality every other month, forewing sizes were the largest in April and the smallest in August. Rearing larvae at a constant temperature demonstrated that forewing size followed the temperature-size rule. Therefore, the converse Bergmann’s rule and the temperature-size rule coexist in this multivoltine species. Our study establishes this species as a useful environmental indicator and supports the idea that the size reduction observed only in Fukushima Prefecture in 2011 was caused by the environmental stress of radioactive pollution. PMID:26197998

  13. Method of hyperspherical functions in a few-body quantum mechanics

    International Nuclear Information System (INIS)

    Dzhibuti, R.I.; Krupennikova, N.B.

    1984-01-01

    A new method for solving a few-body problem in quantum mechanics based on the expansion of the wave function of many-particle system in terms of basis hyperspherical functions is outlined in the monograph. This method gives the possibility to obtain important results in nuclear physics. A materials of general character is presented which can be useful when considering a few-body problem in atomic and molecular physics as well as in elementary particle physics. The paper deals with the theory of hyperspherical functions and the method of expansion in terms of hyperspherical functions basis can be formally considered as a certain generalization of the partial expansion method in the two-body problem. The Raynal-Revai theory is stated for the three-body problem and coe-- fficients of unitary transformations for four-particle hyperspherical function coefficients are introduced. Five-particle hyperspherical functions are introduced and an attempt of generalization of the theory for the systems With any number of particles has been made. The rules of plotting symmetrized hyperspherical functions for three and four identical particles are given. Also described is the method of expansion in terms of hyperspherical functions basis in the coordinate and impulse representations for discrete and continuous spectrum, respectively

  14. The NK1R-/- mouse phenotype suggests that small body size, with a sex- and diet-dependent excess in body mass and fat, are physical biomarkers for a human endophenotype with vulnerability to attention deficit hyperactivity disorder.

    Science.gov (United States)

    Pillidge, Katharine; Heal, David J; Stanford, S Clare

    2016-09-01

    The abnormal behaviour of NK1R-/- mice (locomotor hyperactivity, inattentiveness and impulsivity in the 5-Choice Serial Reaction-Time Test) is arguably analogous to that of patients with attention deficit hyperactivity disorder (ADHD). Evidence suggests that small body size and increased body weight are risk factors for ADHD. Here, we compared the body size, body mass and body composition of male and female NK1R-/- mice and their wildtypes that had been fed either standard laboratory chow or a high-fat (45%: 'Western') diet. Male NK1R-/- mice from both cohorts were approximately 7% shorter than wildtypes. A similar trend was evident in females. Male NK1R-/- mice fed the normal diet weighed less than wildtypes but the 'body mass index' ('mBMI': weight (mg)/length (cm)(2)) of female NK1R-/- mice was higher than wildtypes. When given the high-fat diet, the mBMI of both male and female NK1R-/- mice was higher than wildtypes. There were no consistent genotype or sex differences in protein, ash or water content of mice from the two cohorts. However, the fat content of male NK1R-/- mice on the Western diet was considerably (35%) higher than wildtypes and resembled that of females from both genotypes. We conclude that a lack of functional NK1R is associated with small body size but increases vulnerability to an increase in mBMI and fat content, especially in males. This phenotype could also be evident in ADHD patients with polymorphism(s) of the TACR1 gene (the human equivalent of Nk1r). © The Author(s) 2016.

  15. Survival Times of Meter-Sized Rock Boulders on the Surface of Airless Bodies

    Science.gov (United States)

    Basilevsky, A. T.; Head, J. W.; Horz, F.; Ramsley, K.

    2015-01-01

    This study considers the survival times of meter-sized rock boulders on the surfaces of several airless bodies. As the starting point, we employ estimates of the survival times of such boulders on the surface of the Moon by[1], then discuss the role of destruction due to day-night temperature cycling, consider the meteorite bombardment environment on the considered bodies in terms of projectile flux and velocities and finally estimate the survival times. Survival times of meter-sized rocks on lunar surface: The survival times of hand specimen-sized rocks exposed to the lunar surface environment were estimated based on experiments modeling the destruction of rocks by meteorite impacts, combined with measurements of the lunar surface meteorite flux, (e.g.,[2]). For estimations of the survival times of meter-sized lunar boulders, [1] suggested a different approach based on analysis of the spatial density of boulders on the rims of small lunar craters of known absolute age. It was found that for a few million years, only a small fraction of the boulders ejected by cratering process are destroyed, for several tens of million years approx.50% are destroyed, and for 200-300 Ma, 90 to 99% are destroyed. Following [2] and other works, [1] considered that the rocks are mostly destroyed by meteorite impacts. Destruction of rocks by thermal-stress. However, high diurnal temperature variations on the surface of the Moon and other airless bodies imply that thermal stresses may also be a cause of surface rock destruction. Delbo et al. [3] interpreted the observed presence of fine debris on the surface of small asteroids as due to thermal surface cycling. They stated that because of the very low gravity on the surface of these bodies, ejecta from meteorite impacts should leave the body, so formation there of fine debris has to be due to thermal cycling. Based on experiments on heating-cooling of cm-scale pieces of ordinary and carbonaceous chondrites and theoretical modeling of

  16. Ideal Body Size as a Mediator for the Gender-Specific Association between Socioeconomic Status and Body Mass Index: Evidence from an Upper-Middle-Income Country in the African Region

    Science.gov (United States)

    Yepes, Maryam; Maurer, Jürgen; Stringhini, Silvia; Viswanathan, Barathi; Gedeon, Jude; Bovet, Pascal

    2016-01-01

    Background: While obesity continues to rise globally, the associations between body size, gender, and socioeconomic status (SES) seem to vary in different populations, and little is known on the contribution of perceived ideal body size in the social disparity of obesity in African countries. Purpose: We examined the gender and socioeconomic…

  17. Impact of Glucose Tolerance Status, Sex, and Body Size on Glucose Absorption Patterns During OGTTs

    DEFF Research Database (Denmark)

    Faerch, K.; Pacini, G.; Nolan, J. J.

    2013-01-01

    OBJECTIVEWe studied whether patterns of glucose absorption during oral glucose tolerance tests (OGTTs) were abnormal in individuals with impaired glucose regulation and whether they were related to sex and body size (height and fat-free mass). We also examined how well differences in insulin......, reflected the differences for these parameters between those with normal and impaired glucose regulation as measured by gold-standard tests.CONCLUSIONSGlucose absorption patterns during an OGTT are significantly related to plasma glucose levels and body size, which should be taken into account when.......RESULTSMore rapid glucose absorption (P 0.036) and reduced late glucose absorption (P 0.039) were observed in the i-IFG group relative to NGT and i-IGT groups. Women with i-IGT had a lower early glucose absorption than did men with i-IGT (P = 0.041); however, this difference did not persist when differences in body...

  18. C. elegans serine-threonine kinase KIN-29 modulates TGFβ signaling and regulates body size formation

    Directory of Open Access Journals (Sweden)

    Cohen Stephen

    2005-04-01

    Full Text Available Background In C. elegans there are two well-defined TGFβ-like signaling pathways. The Sma/Mab pathway affects body size morphogenesis, male tail development and spicule formation while the Daf pathway regulates entry into and exit out of the dauer state. To identify additional factors that modulate TGFβ signaling in the Sma/Mab pathway, we have undertaken a genetic screen for small animals and have identified kin-29. Results kin-29 encodes a protein with a cytoplasmic serine-threonine kinase and a novel C-terminal domain. The kinase domain is a distantly related member of the EMK (ELKL motif kinase family, which interacts with microtubules. We show that the serine-threonine kinase domain has in vitro activity. kin-29 mutations result in small animals, but do not affect male tail morphology as do several of the Sma/Mab signal transducers. Adult worms are smaller than the wild-type, but also develop more slowly. Rescue by kin-29 is achieved by expression in neurons or in the hypodermis. Interaction with the dauer pathway is observed in double mutant combinations, which have been seen with Sma/Mab pathway mutants. We show that kin-29 is epistatic to the ligand dbl-1, and lies upstream of the Sma/Mab pathway target gene, lon-1. Conclusion kin-29 is a new modulator of the Sma/Mab pathway. It functions in neurons and in the hypodermis to regulate body size, but does not affect all TGFβ outputs, such as tail morphogenesis.

  19. Body Image and Body Type Preferences in St. Kitts, Caribbean: A Cross-Cultural Comparison with U.S. Samples regarding Attitudes towards Muscularity, Body Fat, and Breast Size

    Directory of Open Access Journals (Sweden)

    Peter B. Gray

    2012-07-01

    Full Text Available We investigated body image in St. Kitts, a Caribbean island where tourism, international media, and relatively high levels of body fat are common. Participants were men and women recruited from St. Kitts (n = 39 and, for comparison, U.S. samples from universities (n = 618 and the Internet (n = 438. Participants were shown computer generated images varying in apparent body fat level and muscularity or breast size and they indicated their body type preferences and attitudes. Overall, there were only modest differences in body type preferences between St. Kitts and the Internet sample, with the St. Kitts participants being somewhat more likely to value heavier women. Notably, however, men and women from St. Kitts were more likely to idealize smaller breasts than participants in the U.S. samples. Attitudes regarding muscularity were generally similar across samples. This study provides one of the few investigations of body preferences in the Caribbean.

  20. Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns

    Science.gov (United States)

    Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E.

    2016-01-01

    Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this ‘ancient’ fern lineage across the tropics. PMID:27412279

  1. Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns.

    Science.gov (United States)

    Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E

    2016-07-13

    Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this 'ancient' fern lineage across the tropics. © 2016 The Author(s).

  2. Body size mediates social and environmental effects on nest building behaviour in a fish with paternal care.

    Science.gov (United States)

    Lehtonen, Topi K; Lindström, Kai; Wong, Bob B M

    2015-07-01

    Body size, social setting, and the physical environment can all influence reproductive behaviours, but their interactions are not well understood. Here, we investigated how male body size, male-male competition, and water turbidity influence nest-building behaviour in the sand goby (Pomatoschistus minutus), a marine fish with exclusive paternal care. We found that environmental and social factors affected the nest characteristics of small and large males differently. In particular, association between male size and the level of nest elaboration (i.e. the amount of sand piled on top of the nest) was positive only under clear water conditions. Similarly, male size and nest entrance size were positively associated only in the absence of competition. Such interactions may, in turn, help to explain the persistence of variation in reproductive behaviours, which-due to their importance in offspring survival-are otherwise expected to be under strong balancing selection.

  3. Experimental Phase Functions of Millimeter-sized Cosmic Dust Grains

    Energy Technology Data Exchange (ETDEWEB)

    Muñoz, O.; Moreno, F.; Guirado, D.; Escobar-Cerezo, J. [Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía s/n, E-18008 Granada (Spain); Vargas-Martín, F. [Department of Electromagnetism and Electronics, University of Murcia, E-30100 Murcia (Spain); Min, M. [SRON Netherlands Institute for Space Research, Sobornnelaan 2, 3584 CA Utrecht (Netherlands); Hovenier, J. W. [Astronomical Institute “Anton Pannekoek,” University of Amsterdam, Science Park 904, 1098 XH, Amsterdam (Netherlands)

    2017-09-01

    We present the experimental phase functions of three types of millimeter-sized dust grains consisting of enstatite, quartz, and volcanic material from Mount Etna, respectively. The three grains present similar sizes but different absorbing properties. The measurements are performed at 527 nm covering the scattering angle range from 3° to 170°. The measured phase functions show two well-defined regions: (i) soft forward peaks and (ii) a continuous increase with the scattering angle at side- and back-scattering regions. This behavior at side- and back-scattering regions is in agreement with the observed phase functions of the Fomalhaut and HR 4796A dust rings. Further computations and measurements (including polarization) for millimeter-sized grains are needed to draw some conclusions about the fluffy or compact structure of the dust grains.

  4. Visual diet versus associative learning as mechanisms of change in body size preferences.

    Directory of Open Access Journals (Sweden)

    Lynda G Boothroyd

    Full Text Available Systematic differences between populations in their preferences for body size may arise as a result of an adaptive 'prepared learning' mechanism, whereby cues to health or status in the local population are internalized and affect body preferences. Alternatively, differences between populations may reflect their 'visual diet' as a cognitive byproduct of mere exposure. Here we test the relative importance of these two explanations for variation in body preferences. Two studies were conducted where female observers were exposed to pictures of high or low BMI women which were either aspirational (healthy, attractive models in high status clothes or non-aspirational (eating disordered patients in grey leotards, or to combinations thereof, in order to manipulate their body-weight preferences which were tested at baseline and at post-test. Overall, results showed good support for visual diet effects (seeing a string of small or large bodies resulted in a change from pre- to post-test whether the bodies were aspirational or not and also some support for the associative learning explanation (exposure to aspirational images of overweight women induced a towards preferring larger bodies, even when accompanied by equal exposure to lower weight bodies in the non-aspirational category. Thus, both influences may act in parallel.

  5. A monequillibrium mary-body systems IV: Respouse function theory

    International Nuclear Information System (INIS)

    Luzzi, R.; Vasconcellos, A.R.; Algarte, A.C.S.

    1987-01-01

    A response function theory for many-body systems arbitrarily away from equilibrium is presented. It is based on the nonequilibrium statistical operator method fully described in a previous article. A formal theory is presented evaluation of transition probabilties and the average values of dynamical quantities in far-from-equilibrium many-body systems under the action of external perturbations. A nonequilibrium thermodynamic Green's function algorithn appropriate for the calculation of response functions and scattering cross sections in terms of a generalized fluctuation-dissipation theorem for far-from-equilibrium systems is also derived. (author) [pt

  6. Body size distribution in ground beetles (Coleoptera: Carabidae) as a possible monitoring method of environmental impacts of transgenic maize

    DEFF Research Database (Denmark)

    Grumo, Davide di; Lövei, Gabor L.

    2015-01-01

    Despite the obligatory post-market environmental monitoring of genetically modified (GM) crops in Europe, there are no available standards on methods. Our aim was to examine the suitability of using changes in carabid body size distribution as a possible monitoring method. The sampling was carried...... informative Lorenz asymmetry coefficients. A total of 6339 carabids belonging to 38 species were captured and indentified. The analysis detected a shift in size distribution between months but no important differences in the assemblages in Bt vs. non-Bt maize plots were found. We concluded that an increasing...... body size trend from spring to autumn was evident, and the use of a multilevel analysis was important to correctly interpret the body size distribution. Therefore, the proposed methods are indeed sensitive to subtle changes in the structure of the carabid assemblages, and they have the potential...

  7. The art of being small : brain-body size scaling in minute parasitic wasps

    NARCIS (Netherlands)

    Woude, van der Emma

    2017-01-01

    Haller’s rule states that small animals have relatively larger brains than large animals. This brain-body size relationship may enable small animals to maintain similar levels of brain performance as large animals. However, it also causes small animals to spend an exceptionally large proportion

  8. An Effect Size Measure for Raju's Differential Functioning for Items and Tests

    Science.gov (United States)

    Wright, Keith D.; Oshima, T. C.

    2015-01-01

    This study established an effect size measure for differential functioning for items and tests' noncompensatory differential item functioning (NCDIF). The Mantel-Haenszel parameter served as the benchmark for developing NCDIF's effect size measure for reporting moderate and large differential item functioning in test items. The effect size of…

  9. Lower limits of ornithischian dinosaur body size inferred from a new Upper Jurassic heterodontosaurid from North America

    Science.gov (United States)

    Butler, Richard J.; Galton, Peter M.; Porro, Laura B.; Chiappe, Luis M.; Henderson, Donald M.; Erickson, Gregory M.

    2010-01-01

    The extremes of dinosaur body size have long fascinated scientists. The smallest (dinosaurs are carnivorous saurischian theropods, and similarly diminutive herbivorous or omnivorous ornithischians (the other major group of dinosaurs) are unknown. We report a new ornithischian dinosaur, Fruitadens haagarorum, from the Late Jurassic of western North America that rivals the smallest theropods in size. The largest specimens of Fruitadens represent young adults in their fifth year of development and are estimated at just 65–75 cm in total body length and 0.5–0.75 kg body mass. They are thus the smallest known ornithischians. Fruitadens is a late-surviving member of the basal dinosaur clade Heterodontosauridae, and is the first member of this clade to be described from North America. The craniodental anatomy and diminutive body size of Fruitadens suggest that this taxon was an ecological generalist with an omnivorous diet, thus providing new insights into morphological and palaeoecological diversity within Dinosauria. Late-surviving (Late Jurassic and Early Cretaceous) heterodontosaurids are smaller and less ecologically specialized than Early (Late Triassic and Early Jurassic) heterodontosaurids, and this ecological generalization may account in part for the remarkable 100-million-year-long longevity of the clade. PMID:19846460

  10. Density-functional errors in ionization potential with increasing system size

    Energy Technology Data Exchange (ETDEWEB)

    Whittleton, Sarah R.; Sosa Vazquez, Xochitl A.; Isborn, Christine M., E-mail: cisborn@ucmerced.edu [Chemistry and Chemical Biology, School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, California 95343 (United States); Johnson, Erin R., E-mail: erin.johnson@dal.ca [Chemistry and Chemical Biology, School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, California 95343 (United States); Department of Chemistry, Dalhousie University, 6274 Coburg Road, Halifax, Nova Scotia B3H 4R2 (Canada)

    2015-05-14

    This work investigates the effects of molecular size on the accuracy of density-functional ionization potentials for a set of 28 hydrocarbons, including series of alkanes, alkenes, and oligoacenes. As the system size increases, delocalization error introduces a systematic underestimation of the ionization potential, which is rationalized by considering the fractional-charge behavior of the electronic energies. The computation of the ionization potential with many density-functional approximations is not size-extensive due to excessive delocalization of the incipient positive charge. While inclusion of exact exchange reduces the observed errors, system-specific tuning of long-range corrected functionals does not generally improve accuracy. These results emphasize that good performance of a functional for small molecules is not necessarily transferable to larger systems.

  11. Birth mass is the key to understanding the negative correlation between lifespan and body size in dogs.

    Science.gov (United States)

    Fan, Rong; Olbricht, Gayla; Baker, Xavior; Hou, Chen

    2016-12-08

    Larger dog breeds live shorter than the smaller ones, opposite of the mass-lifespan relationship observed across mammalian species. Here we use data from 90 dog breeds and a theoretical model based on the first principles of energy conservation and life history tradeoffs to explain the negative correlation between longevity and body size in dogs. We found that the birth/adult mass ratio of dogs scales negatively with adult size, which is different than the weak interspecific scaling in mammals. Using the model, we show that this ratio, as an index of energy required for growth, is the key to understanding why the lifespan of dogs scales negatively with body size. The model also predicts that the difference in mass-specific lifetime metabolic energy usage between dog breeds is proportional to the difference in birth/adult mass ratio. Empirical data on lifespan, body mass, and metabolic scaling law of dogs strongly supports this prediction.

  12. Glenoid version and size: does gender, ethnicity, or body size play a role?

    Science.gov (United States)

    Piponov, Hristo Ivanov; Savin, David; Shah, Neal; Esposito, Domenic; Schwartz, Brian; Moretti, Vincent; Goldberg, Benjamin

    2016-11-01

    Variations in glenoid morphology among patients of different gender, body habitus, and ethnicity have been of interest for surgeons. Understanding these anatomical variations is a critical step in restoring normal glenohumeral structure during shoulder reconstruction surgery. Retrospective review of 108 patient shoulder CT scans was performed and glenoid version, AP diameter and height were measured. Statistical multiple regression models were used to investigate the ability of gender and ethnicity to predict glenoid AP diameter, height, and version independently of patient weight and height. The mean glenoid AP diameter was 24.7 ± 3.5, the mean glenoid height was 31.7 ± 3.7, and the mean glenoid version was 0.05 ± 9.05. According to our regression models, males would be expected to exhibit 8.4° more glenoid retroversion than females (p = 0.003) and have 2.9 mm larger glenoid height compared to females (p = 0.002). The predicted male glenoid AP diameter was 3.4 mm higher than that in females (p variations in glenoid size and version are observed among ethnicities, larger sample size ethnic groups will be necessary to explore the precise relations. Surgeons should consider gender and ethnic variations in the pre-operative planning and surgical restoration of the native glenohumeral relationship. Anatomic Study.

  13. Effects of Abiotic Factors on the Geographic Distribution of Body Size Variation and Chromosomal Polymorphisms in Two Neotropical Grasshopper Species (Dichroplus: Melanoplinae: Acrididae

    Directory of Open Access Journals (Sweden)

    Claudio J. Bidau

    2012-01-01

    Full Text Available We review the effects of abiotic factors on body size in two grasshopper species with large geographical distributions: Dichroplus pratensis and D. vittatus, inhabiting Argentina in diverse natural habitats. Geographical spans for both species provide an opportunity to study the effects of changes in abiotic factors on body size. The analyses of body size distribution in both species revealed a converse Bergmannian pattern: body size is positively correlated with latitude, altitude, and seasonality that influences time available for development and growth. Allen’s rule is also inverted. Morphological variability increases towards the ends of the Bergmannian clines and, in D. pratensis, is related with a central-marginal distribution of chromosomal variants that influence recombination. The converse Bergmannian patterns influence sexual size dimorphism in both species but in different fashions. Body size variation at a microspatial scale in D. pratensis is extremely sensitive to microclimatic clines. We finally compare our results with those for other Orthopteran species.

  14. Body size and the rate of spread of invasive ladybird beetles in North America

    Czech Academy of Sciences Publication Activity Database

    Hemptinne, J. L.; Magro, A.; Evans, E.W.; Dixon, Anthony F. G.

    2012-01-01

    Roč. 14, č. 3 (2012), s. 595-605 ISSN 1387-3547 Institutional support: RVO:67179843 Keywords : Invasiveness * Body size * Reproductive rate * Coccinella septempunctata * Harmonia axyridis Subject RIV: EH - Ecology , Behaviour Impact factor: 2.509, year: 2012

  15. A critical evaluation of the insect body size model and causes of metamorphosis in solitary bees

    Science.gov (United States)

    The insect body size model posits that adult size is determined by growth rate and the duration of growth during the larval stage of development. Within the model, growth rate is regulated by many mechanistic elements that are influenced by both internal and external factors. However, the duration o...

  16. Body composition and pulmonary function in Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    Saba eSheikh

    2014-04-01

    Full Text Available Background: Lower body mass index (BMI is associated with worse pulmonary function in cystic fibrosis (CF. Hypothesis: Lean body mass (LBM is more strongly associated with pulmonary function than BMI is.Methods: Anthropometrics, body composition by dual x-ray absorptiometry, and pulmonary function were determined in pancreatic insufficient CF (PI-CF youth. Sex and age-adjusted Z-scores (BMI-Z, LBMI-Z, FMI-Z were generated for CF and controls. 1 Associations of BMI-Z with LBMI-Z and FMI-Z and 2 age-adjusted associations of BMI-Z, LBMI-Z, and FMI-Z with FEV1%-predicted were tested. Results: 208 PI-CF subjects had lower BMI-Z, LBMI-Z, FMI-Z compared to 390 controls. BMI-Z was associated with lower LBMI-Z (pConclusions: In PI-CF youth, deficits in LBM were apparent. At lower BMI percentiles, BMI may not accurately depict LBM in PI-CF. In under-nourished PI-CF youth this preservation of FM in preference to LBM is relevant since LBMI-Z, but not FMI-Z, is positively associated with FEV1%-predicted. LBMI is more strongly associated with lung function compared to BMI, especially in the undernourished child and adolescent with PI-CF.

  17. A six decades long follow-up on body size in adolescents from Zagreb, Croatia (1951-2010).

    Science.gov (United States)

    Zajc Petranović, Matea; Tomas, Željka; Smolej Narančić, Nina; Škarić-Jurić, Tatjana; Veček, Andrea; Miličić, Jasna

    2014-03-01

    Most studies analysing the influence of socioeconomic deterioration on body size focus on the impact of food shortages and diseases on the growth in early childhood. To evaluate how socioeconomic conditions influence the growth during the adolescence, we tracked the body size of 15-19 year-olds over the last sixty years covering the socialist period (1951-1990), the war (1991-1995) and the transition to capitalistic economy. This study of Zagreb, Croatia, adolescent population provides information on the secular trend in height, weight and Body Mass Index (BMI) and examines their relation with Real Gross Domestic Product. From 1951 to 2010 the girls' height approximately increased by 6.2cm and weight by 6.8kg, while the boys' height increased by 12.2cm and weight by 17.3kg. Prior to 1991 mean BMI in girls was higher than in boys, but from 1991 on, the interrelation between the sexes has been opposite, possibly mirroring the cultural trends that started in mid-1970s and reflecting higher sensitivity of boys to the socioeconomic changes. In conclusion, the secular trend in body size over the investigated period reflects the positive economic trends interrupted by the war. The recent increase in BMI corresponds to the country's economic recovery and indicates the "nutrition transition". Copyright © 2013 Elsevier B.V. All rights reserved.

  18. The Influence of Age and Sex on Genetic Associations with Adult Body Size and Shape: A Large-Scale Genome-Wide Interaction Study

    NARCIS (Netherlands)

    T.W. Winkler (Thomas W.); A.E. Justice (Anne); M.J. Graff (Maud J.L.); Barata, L. (Llilda); M.F. Feitosa (Mary Furlan); Chu, S. (Su); J. Czajkowski (Jacek); T. Esko (Tõnu); M. Fall (Magnus); T.O. Kilpeläinen (Tuomas); Y. Lu (Yingchang); R. Mägi (Reedik); E. Mihailov (Evelin); T.H. Pers (Tune); Rüeger, S. (Sina); A. Teumer (Alexander); G.B. Ehret (Georg); T. Ferreira (Teresa); N.L. Heard-Costa (Nancy); J. Karjalainen (Juha); V. Lagou (Vasiliki); A. Mahajan (Anubha); Neinast, M.D. (Michael D.); I. Prokopenko (Inga); J. Simino (Jeannette); T.M. Teslovich (Tanya M.); R. Jansen; H.J. Westra (Harm-Jan); C.C. White (Charles); D. Absher (Devin); T.S. Ahluwalia (Tarunveer Singh); S. Ahmad (Shafqat); E. Albrecht (Eva); A.C. Alves (Alexessander Couto); Bragg-Gresham, J.L. (Jennifer L.); A.J. de Craen (Anton); J.C. Bis (Joshua); A. Bonnefond (Amélie); G. Boucher (Gabrielle); G. Cadby (Gemma); Y.-C. Cheng (Yu-Ching); Chiang, C.W. (Charleston W K); G. Delgado; A. Demirkan (Ayşe); N. Dueker (Nicole); N. Eklund (Niina); G. Eiriksdottir (Gudny); J. Eriksson (Joel); B. Feenstra (Bjarke); K. Fischer (Krista); F. Frau (Francesca); T.E. Galesloot (Tessel); F. Geller (Frank); A. Goel (Anuj); M. Gorski (Mathias); T.B. Grammer (Tanja); S. Gustafsson (Stefan); Haitjema, S. (Saskia); J.J. Hottenga (Jouke Jan); J.E. Huffman (Jennifer); A.U. Jackson (Anne); K.B. Jacobs (Kevin); A. Johansson (Åsa); M. Kaakinen (Marika); M.E. Kleber (Marcus); J. Lahti (Jari); I.M. Leach (Irene Mateo); Lehne, B. (Benjamin); Liu, Y. (Youfang); K.S. Lo; M. Lorentzon (Mattias); J. Luan (Jian'An); P.A. Madden (Pamela); M. Mangino (Massimo); B. McKnight (Barbara); Medina-Gomez, C. (Carolina); K.L. Monda (Keri); M.E. Montasser (May E.); G. Müller (Gabriele); M. Müller-Nurasyid (Martina); I.M. Nolte (Ilja); Panoutsopoulou, K. (Kalliope); L. Pascoe (Laura); L. Paternoster (Lavinia); N.W. Rayner (Nigel William); F. Renström (Frida); Rizzi, F. (Federica); L.M. Rose (Lynda); Ryan, K.A. (Kathy A.); P. Salo (Perttu); S. Sanna (Serena); H. Scharnagl (Hubert); Shi, J. (Jianxin); A.V. Smith (Albert Vernon); L. Southam (Lorraine); A. Stancáková (Alena); V. Steinthorsdottir (Valgerdur); R.J. Strawbridge (Rona); Sung, Y.J. (Yun Ju); I. Tachmazidou (Ioanna); T. Tanaka (Toshiko); G. Thorleifsson (Gudmar); S. Trompet (Stella); N. Pervjakova (Natalia); J.P. Tyrer (Jonathan); L. Vandenput (Liesbeth); S.W. Van Der Laan (Sander W.); N. van der Velde (Nathalie); J. van Setten (Jessica); J.V. van Vliet-Ostaptchouk (Jana); N. Verweij (Niek); E. Vlachopoulou (Efthymia); L. Waite (Lindsay); S.R. Wang (Sophie); Z. Wang (Zhaoming); S.H. Wild (Sarah); C. Willenborg (Christina); J.F. Wilson (James); A. Wong (Andrew); Yang, J. (Jian); L. Yengo (Loic); L.M. Yerges-Armstrong (Laura); Yu, L. (Lei); W. Zhang (Weihua); Zhao, J.H. (Jing Hua); E.A. Andersson (Ehm Astrid); S.J.L. Bakker (Stephan); D. Baldassarre (Damiano); Banasik, K. (Karina); Barcella, M. (Matteo); Barlassina, C. (Cristina); C. Bellis (Claire); P. Benaglio (Paola); J. Blangero (John); M. Blüher (Matthias); Bonnet, F. (Fabrice); L.L. Bonnycastle (Lori); H.A. Boyd (Heather); M. Bruinenberg (M.); Buchman, A.S. (Aron S.); H. Campbell (Harry); Y.D. Chen (Y.); P.S. Chines (Peter); S. Claudi-Boehm (Simone); J.W. Cole (John W.); F.S. Collins (Francis); E.J.C. de Geus (Eco); L.C.P.G.M. de Groot (Lisette); M. Dimitriou (Maria); J. Duan (Jubao); S. Enroth (Stefan); E. Eury (Elodie); A.-E. Farmaki (Aliki-Eleni); N.G. Forouhi (Nita); N. Friedrich (Nele); P.V. Gejman (Pablo); B. Gigante (Bruna); N. Glorioso (Nicola); A. Go (Attie); R.F. Gottesman (Rebecca); J. Gräßler (Jürgen); H. Grallert (Harald); N. Grarup (Niels); Gu, Y.-M. (Yu-Mei); L. Broer (Linda); A.C. Ham (Annelies); T. Hansen (T.); T.B. Harris (Tamara); C.A. Hartman (Catharina A.); Hassinen, M. (Maija); N. Hastie (Nick); A.T. Hattersley (Andrew); A.C. Heath (Andrew); A.K. Henders (Anjali); D.G. Hernandez (Dena); H.L. Hillege (Hans); O.L. Holmen (Oddgeir); G.K. Hovingh (Kees); J. Hui (Jennie); Husemoen, L.L. (Lise L.); Hutri-Kähönen, N. (Nina); P.G. Hysi (Pirro); T. Illig (Thomas); P.L. de Jager (Philip); S. Jalilzadeh (Shapour); T. Jorgensen (Torben); J.W. Jukema (Jan Wouter); Juonala, M. (Markus); S. Kanoni (Stavroula); M. Karaleftheri (Maria); K.T. Khaw; L. Kinnunen (Leena); T. Kittner (Thomas); W. Koenig (Wolfgang); I. Kolcic (Ivana); P. Kovacs (Peter); Krarup, N.T. (Nikolaj T.); W. Kratzer (Wolfgang); Krüger, J. (Janine); Kuh, D. (Diana); M. Kumari (Meena); T. Kyriakou (Theodosios); C. Langenberg (Claudia); L. Lannfelt (Lars); C. Lanzani (Chiara); V. Lotay (Vaneet); L.J. Launer (Lenore); K. Leander (Karin); J. Lindström (Jaana); A. Linneberg (Allan); Liu, Y.-P. (Yan-Ping); S. Lobbens (Stéphane); R.N. Luben (Robert); V. Lyssenko (Valeriya); S. Männistö (Satu); P.K. Magnusson (Patrik); W.L. McArdle (Wendy); C. Menni (Cristina); S. Merger (Sigrun); L. Milani (Lili); Montgomery, G.W. (Grant W.); A.P. Morris (Andrew); N. Narisu (Narisu); M. Nelis (Mari); K.K. Ong (Ken); A. Palotie (Aarno); L. Perusse (Louis); I. Pichler (Irene); M.G. Pilia (Maria Grazia); A. Pouta (Anneli); Rheinberger, M. (Myriam); Ribel-Madsen, R. (Rasmus); Richards, M. (Marcus); K.M. Rice (Kenneth); T.K. Rice (Treva K.); C. Rivolta (Carlo); V. Salomaa (Veikko); A.R. Sanders (Alan); M.A. Sarzynski (Mark A.); S. Scholtens (Salome); R.A. Scott (Robert); W.R. Scott (William R.); S. Sebert (Sylvain); S. Sengupta (Sebanti); B. Sennblad (Bengt); T. Seufferlein (Thomas); A. Silveira (Angela); P.E. Slagboom (Eline); J.H. Smit (Jan); T. Sparsø (Thomas); K. Stirrups (Kathy); R.P. Stolk (Ronald); H.M. Stringham (Heather); Swertz, M.A. (Morris A.); A.J. Swift (Amy); A.C. Syvänen; S.-T. Tan (Sian-Tsung); B. Thorand (Barbara); A. Tönjes (Anke); Tremblay, A. (Angelo); E. Tsafantakis (Emmanouil); P.J. van der Most (Peter); U. Völker (Uwe); M.-C. Vohl (Marie-Claude); J.M. Vonk (Judith); M. Waldenberger (Melanie); Walker, R.W. (Ryan W.); R. Wennauer (Roman); E. Widen; G.A.H.M. Willemsen (Gonneke); T. Wilsgaard (Tom); A.F. Wright (Alan); M.C. Zillikens (Carola); S. Van Dijk (Suzanne); N.M. van Schoor (Natasja); F.W. Asselbergs (Folkert); P.I.W. de Bakker (Paul); J.S. Beckmann (Jacques); J.P. Beilby (John); D.A. Bennett (David A.); R.N. Bergman (Richard); S.M. Bergmann (Sven); C.A. Böger (Carsten); B.O. Boehm (Bernhard); E.A. Boerwinkle (Eric); D.I. Boomsma (Dorret); S.R. Bornstein (Stefan); E.P. Bottinger (Erwin); C. Bouchard (Claude); J.C. Chambers (John); S.J. Chanock (Stephen); D.I. Chasman (Daniel); F. Cucca (Francesco); D. Cusi (Daniele); G.V. Dedoussis (George); J. Erdmann (Jeanette); K. Hagen (Knut); D. Evans; U. de Faire (Ulf); M. Farrall (Martin); L. Ferrucci (Luigi); I. Ford (Ian); L. Franke (Lude); P.W. Franks (Paul); P. Froguel (Philippe); R.T. Gansevoort (Ron); C. Gieger (Christian); H. Grönberg (Henrik); V. Gudnason (Vilmundur); U. Gyllensten (Ulf); P. Hall (Per); A. Hamsten (Anders); P. van der Harst (Pim); C. Hayward (Caroline); M. Heliovaara (Markku); C. Hengstenberg (Christian); A.A. Hicks (Andrew); A. Hingorani (Aroon); A. Hofman (Albert); Hu, F. (Frank); H.V. Huikuri (Heikki); K. Hveem (Kristian); A. James (Alan); Jordan, J.M. (Joanne M.); A. Jula (Antti); M. Kähönen (Mika); E. Kajantie (Eero); S. Kathiresan (Sekar); L.A.L.M. Kiemeney (Bart); M. Kivimaki (Mika); P. Knekt; H. Koistinen (Heikki); J.S. Kooner (Jaspal S.); S. Koskinen (Seppo); J. Kuusisto (Johanna); W. Maerz (Winfried); N.G. Martin (Nicholas); M. Laakso (Markku); T.A. Lakka (Timo); T. Lehtimäki (Terho); G. Lettre (Guillaume); D.F. Levinson (Douglas); W.H.L. Kao (Wen); M.L. Lokki; Mäntyselkä, P. (Pekka); M. Melbye (Mads); A. Metspalu (Andres); B.D. Mitchell (Braxton); F.L. Moll (Frans); J.C. Murray (Jeffrey); A.W. Musk (Arthur); M.S. Nieminen (Markku); I. Njølstad (Inger); C. Ohlsson (Claes); A.J. Oldehinkel (Albertine); B.A. Oostra (Ben); C. Palmer (Cameron); J.S. Pankow (James); G. Pasterkamp (Gerard); N.L. Pedersen (Nancy); O. Pedersen (Oluf); B.W.J.H. Penninx (Brenda); M. Perola (Markus); A. Peters (Annette); O. Polasek (Ozren); P.P. Pramstaller (Peter Paul); Psaty, B.M. (Bruce M.); Qi, L. (Lu); T. Quertermous (Thomas); Raitakari, O.T. (Olli T.); T. Rankinen (Tuomo); R. Rauramaa (Rainer); P.M. Ridker (Paul); J.D. Rioux (John); F. Rivadeneira Ramirez (Fernando); J.I. Rotter (Jerome I.); I. Rudan (Igor); H.M. den Ruijter (Hester ); J. Saltevo (Juha); N. Sattar (Naveed); Schunkert, H. (Heribert); P.E.H. Schwarz (Peter); A.R. Shuldiner (Alan); J. Sinisalo (Juha); H. Snieder (Harold); T.I.A. Sørensen (Thorkild); T.D. Spector (Timothy); Staessen, J.A. (Jan A.); Stefania, B. (Bandinelli); U. Thorsteinsdottir (Unnur); M. Stumvoll (Michael); J.-C. Tardif (Jean-Claude); E. Tremoli (Elena); J. Tuomilehto (Jaakko); A.G. Uitterlinden (André); M. Uusitupa (Matti); A.L.M. Verbeek; S.H.H.M. Vermeulen (Sita); J. Viikari (Jorma); Vitart, V. (Veronique); H. Völzke (Henry); P. Vollenweider (Peter); G. Waeber (Gérard); M. Walker (Mark); H. Wallaschofski (Henri); N.J. Wareham (Nick); H. Watkins (Hugh); E. Zeggini (Eleftheria); A. Chakravarti (Aravinda); Clegg, D.J. (Deborah J.); L.A. Cupples (Adrienne); P. Gordon-Larsen (Penny); C.E. Jaquish (Cashell); D.C. Rao (Dabeeru C.); Abecasis, G.R. (Goncalo R.); T.L. Assimes (Themistocles); I.E. Barroso (Inês); S.I. Berndt (Sonja); M. Boehnke (Michael); P. Deloukas (Panagiotis); C.S. Fox (Caroline); L. Groop (Leif); D. Hunter (David); E. Ingelsson (Erik); R.C. Kaplan (Robert); McCarthy, M.I. (Mark I.); K.L. Mohlke (Karen); J.R. O´Connell; Schlessinger, D. (David); D.P. Strachan (David); J-A. Zwart (John-Anker); C.M. van Duijn (Cornelia); J.N. Hirschhorn (Joel); C.M. Lindgren (Cecilia M.); I.M. Heid (Iris); K.E. North (Kari); I.B. Borecki (Ingrid); Z. Kutalik (Zoltán); R.J.F. Loos (Ruth)

    2015-01-01

    textabstractGenome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ

  19. Reproductive success in a natural population of male three-spined stickleback Gasterosteus aculeatus: effects of nuptial colour, parasites and body size.

    Science.gov (United States)

    Sparkes, T C; Rush, V; Kopp, D A; Foster, S A

    2013-05-01

    The effects of nuptial colour, parasites and body size on reproductive success were examined in a natural population of three-spined stickleback Gasterosteus aculeatus. Reproductive males were collected, with the contents of their nests, during the embryo-guarding stage from Lynne Lake (Cook Inlet, Alaska, U.S.A.), and nuptial colour, infection status and body size were recorded. Regression analysis revealed that male body size was the only predictor, of those measured, of reproductive success in nature. © 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

  20. BODY SIZE AND HAREM SIZE IN MALE RED-WINGED BLACKBIRDS: MANIPULATING SELECTION WITH SEX-SPECIFIC FEEDERS.

    Science.gov (United States)

    Rohwer, Sievert; Langston, Nancy; Gori, Dave

    1996-10-01

    We experimentally manipulated the strength of selection in the field on red-winged blackbirds (Agelaius phoeniceus) to test hypotheses about contrasting selective forces that favor either large or small males in sexually size dimorphic birds. Selander (1972) argued that sexual selection favors larger males, while survival selection eventually stabilizes male size because larger males do not survive as well as smaller males during harsh winters. Searcy (1979a) proposed instead that sexual selection may be self limiting: male size might be stabilized not by overwinter mortality, but by breeding-season sexual selection that favors smaller males. Under conditions of energetic stress, smaller males should be able to display more and thus achieve higher reproductive success. Using feeders that provisioned males or females but not both, we produced conditions that mimicked the extremes of natural conditions. We found experimental support for the hypothesis that when food is abundant, sexual selection favors larger males. But even under conditions of severe energetic stress, smaller males did not gain larger harems, as the self-limiting hypothesis predicted. Larger males were more energetically stressed than smaller males, but in ways that affected their future reproductive output rather than their current reproductive performance. Stressed males that returned had smaller wings and tails than those that did not return; among returning stressed males, relative harem sizes were inversely related to wing and tail length. Thus, male body size may be stabilized not by survival costs during the non-breeding season, nor by energetic costs during the breeding season, but by costs of future reproduction that larger males pay for their increased breeding-season effort. © 1996 The Society for the Study of Evolution.

  1. Anemia and Iron Status Among Different Body Size Phenotypes in Chinese Adult Population: a Nation-Wide, Health and Nutrition Survey.

    Science.gov (United States)

    Li, Jiang; Xiao, Cheng; Yang, Hui; Zhou, Yun; Wang, Rui; Cao, Yongtong

    2017-12-09

    Previous studies have shown that there is a controversial relationship between iron homeostasis and obesity. This study aims to explore the relationship of anemia and iron status with different body size phenotypes in adult Chinese population. Using information on iron status-related parameters and lifestyle data from 8462 participants of the 2009 wave of China Health and Nutrition Survey (2009 CHNS), we performed multivariable logistic regression analyses to estimate the odds ratios (ORs) for the risk of anemia and iron parameters according to different body size phenotypes. Participants with higher body mass index (BMI) had a lower anemia prevalence with significant trends in both metabolic status groups (P different metabolic status groups and in different body size phenotypes, respectively. The ORs for higher ferritin and transferrin increased across different body size phenotypes in both genders, and for sTfR/log ferritin index decreased (P < 0.01 for trend). This association was still statistically significant after adjustment for multiple confounders. We found an inverse association of BMI levels with the prevalence of anemia and strong association of serum ferritin and transferrin with higher risk of obesity or overweight in both metabolic status groups.

  2. Association between body size and blood pressure in children from different ethnic origins

    NARCIS (Netherlands)

    LA de Hoog, Marieke; van Eijsden, Manon; Stronks, Karien; Gemke, Reinoud J. B. J.; Vrijkotte, Tanja G. M.

    2012-01-01

    Objective: To assess associations between body size and blood pressure in children (5-6 years) from different ethnic origins. Method: Five ethnic groups of the ABCD cohort were examined: Dutch (n=1 923), Turkish (n=99), Moroccan (n=187), Black-African (n=67) and Black-Caribbean (n=121). Data on

  3. High-intensity functional training improves functional movement and body composition among cancer survivors: a pilot study.

    Science.gov (United States)

    Heinrich, K M; Becker, C; Carlisle, T; Gilmore, K; Hauser, J; Frye, J; Harms, C A

    2015-11-01

    This pilot study investigated feasibility and preliminary efficacy of a high-intensity functional training (HIFT) group-exercise programme among adult cancer survivors within 5 years of last cancer treatment. Eight participants were assigned to a 5-week, 3 days/week HIFT intervention with four testing sessions and 12 workouts along with mobility and stretching exercises. Feasibility was assessed by initiation, adherence, and acceptability. Efficacy was determined by changes from baseline to post-test in health-related quality of life, body composition and functional movement. The recruitment rate was 80% and the adherence rate was 75%. Significant improvements were found for emotional functioning (P = 0.042) and body composition (lean mass +3.8 ± 2.1 kg, P = 0.008; fat mass -3.3 ± 1.0 kg, P = 0.001; body fat percentage -4.7 ± 1.2%, P body strength and power (P = 0.009), aerobic capacity and endurance (P = 0.039), and perceived difficulty for flexibility (P = 0.012). Five weeks of HIFT training was well-received and feasible for most cancer survivors, and effective for improving emotional functioning, body composition and functional movement. © 2015 John Wiley & Sons Ltd.

  4. Small body size and extreme cortical bone remodeling indicate phyletic dwarfism in Magyarosaurus dacus (Sauropoda: Titanosauria).

    Science.gov (United States)

    Stein, Koen; Csiki, Zoltan; Rogers, Kristina Curry; Weishampel, David B; Redelstorff, Ragna; Carballido, Jose L; Sander, P Martin

    2010-05-18

    Sauropods were the largest terrestrial tetrapods (>10(5) kg) in Earth's history and grew at rates that rival those of extant mammals. Magyarosaurus dacus, a titanosaurian sauropod from the Upper Cretaceous (Maastrichtian) of Romania, is known exclusively from small individuals (dwarfism (phyletic nanism) in dinosaurs, but a recent study suggested that the small Romanian titanosaurs actually represent juveniles of a larger-bodied taxon. Here we present strong histological evidence that M. dacus was indeed a dwarf (phyletic nanoid). Bone histological analysis of an ontogenetic series of Magyarosaurus limb bones indicates that even the smallest Magyarosaurus specimens exhibit a bone microstructure identical to fully mature or old individuals of other sauropod taxa. Comparison of histologies with large-bodied sauropods suggests that Magyarosaurus had an extremely reduced growth rate, but had retained high basal metabolic rates typical for sauropods. The uniquely decreased growth rate and diminutive body size in Magyarosaurus were adaptations to life on a Cretaceous island and show that sauropod dinosaurs were not exempt from general ecological principles limiting body size.

  5. Influence of detector pixel size, TOF resolution and DOI on image quality in MR-compatible whole-body PET.

    Science.gov (United States)

    Thoen, Hendrik; Keereman, Vincent; Mollet, Pieter; Van Holen, Roel; Vandenberghe, Stefaan

    2013-09-21

    The optimization of a whole-body PET system remains a challenging task, as the imaging performance is influenced by a complex interaction of different design parameters. However, it is not always clear which parameters have the largest impact on image quality and are most eligible for optimization. To determine this, we need to be able to assess their influence on image quality. We performed Monte-Carlo simulations of a whole-body PET scanner to predict the influence on image quality of three detector parameters: the TOF resolution, the transverse pixel size and depth-of-interaction (DOI)-correction. The inner diameter of the PET scanner was 65 cm, small enough to allow physical integration into a simultaneous PET-MR system. Point sources were used to evaluate the influence of transverse pixel size and DOI-correction on spatial resolution as function of radial distance. To evaluate the influence on contrast recovery and pixel noise a cylindrical phantom of 35 cm diameter was used, representing a large patient. The phantom contained multiple hot lesions with 5 mm diameter. These lesions were placed at radial distances of 50, 100 and 150 mm from the center of the field-of-view, to be able to study the effects at different radial positions. The non-prewhitening (NPW) observer was used for objective analysis of the detectability of the hot lesions in the cylindrical phantom. Based on this analysis the NPW-SNR was used to quantify the relative improvements in image quality due to changes of the variable detector parameters. The image quality of a whole-body PET scanner can be improved significantly by reducing the transverse pixel size from 4 to 2.6 mm and improving the TOF resolution from 600 to 400 ps and further from 400 to 200 ps. Compared to pixel size, the TOF resolution has the larger potential to increase image quality for the simulated phantom. The introduction of two layer DOI-correction only leads to a modest improvement for the spheres at radial

  6. Influence of detector pixel size, TOF resolution and DOI on image quality in MR-compatible whole-body PET

    International Nuclear Information System (INIS)

    Thoen, Hendrik; Keereman, Vincent; Mollet, Pieter; Van Holen, Roel; Vandenberghe, Stefaan

    2013-01-01

    The optimization of a whole-body PET system remains a challenging task, as the imaging performance is influenced by a complex interaction of different design parameters. However, it is not always clear which parameters have the largest impact on image quality and are most eligible for optimization. To determine this, we need to be able to assess their influence on image quality. We performed Monte-Carlo simulations of a whole-body PET scanner to predict the influence on image quality of three detector parameters: the TOF resolution, the transverse pixel size and depth-of-interaction (DOI)-correction. The inner diameter of the PET scanner was 65 cm, small enough to allow physical integration into a simultaneous PET-MR system. Point sources were used to evaluate the influence of transverse pixel size and DOI-correction on spatial resolution as function of radial distance. To evaluate the influence on contrast recovery and pixel noise a cylindrical phantom of 35 cm diameter was used, representing a large patient. The phantom contained multiple hot lesions with 5 mm diameter. These lesions were placed at radial distances of 50, 100 and 150 mm from the center of the field-of-view, to be able to study the effects at different radial positions. The non-prewhitening (NPW) observer was used for objective analysis of the detectability of the hot lesions in the cylindrical phantom. Based on this analysis the NPW-SNR was used to quantify the relative improvements in image quality due to changes of the variable detector parameters. The image quality of a whole-body PET scanner can be improved significantly by reducing the transverse pixel size from 4 to 2.6 mm and improving the TOF resolution from 600 to 400 ps and further from 400 to 200 ps. Compared to pixel size, the TOF resolution has the larger potential to increase image quality for the simulated phantom. The introduction of two layer DOI-correction only leads to a modest improvement for the spheres at radial distance of

  7. Mammal Reproductive Strategies Driven by Offspring Mortality-Size Relationships

    DEFF Research Database (Denmark)

    Sibly, Richard M.; Brown, James H.

    2009-01-01

    Trade-offs have long been a major theme in life-history theory, but they have been hard to document. We introduce a new method that reveals patterns of divergent trade-offs after adjusting for the pervasive variation in rate of resource allocation to offspring as a function of body size and lifes......Trade-offs have long been a major theme in life-history theory, but they have been hard to document. We introduce a new method that reveals patterns of divergent trade-offs after adjusting for the pervasive variation in rate of resource allocation to offspring as a function of body size...

  8. Body size, growth and life span: implications for the polewards range shift of Octopus tetricus in south-eastern Australia.

    Science.gov (United States)

    Ramos, Jorge E; Pecl, Gretta T; Moltschaniwskyj, Natalie A; Strugnell, Jan M; León, Rafael I; Semmens, Jayson M

    2014-01-01

    Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters.

  9. Litter size of Danish crossbred sows increased without changes in sow body dimensions over a thirteen year period

    DEFF Research Database (Denmark)

    Nielsen, S. E.; Kristensen, A. R.; Moustsen, V. Aa

    2018-01-01

    dimensions and litter size was also investigated. Depth, width, length and height were measured from 405 Danish crossbred sows in 10 different herds, classified in groups of parity 1, 2, 3, 4, 5, 6 and ≥ 7. By Linear Mixed-Effects Models with depth, width, length and height in turn as response variable......The purpose of this study was to investigate if body dimensions of Danish crossbred sows (Yorkshire x Landrace) had increased compared to a previous Danish study from 2004. In addition, and as an expected potential benefit of increased body dimensions, a potential correlation between body...... and parity and herd as explanatory variables, estimated means, 5th and 95th percentiles, minimum and maximum observation were recorded. Furthermore, a weighted index for litter size (denoted as the “litter size potential”) was used as response variable with depth, width, length, height and parity...

  10. Functional Body Composition and Related Aspects in Research on Obesity and Cachexia

    Science.gov (United States)

    Müller, M.J.; Baracos, V.; Bosy-Westphal, A.; Dulloo, A.; Eckel, J.; Fearon, K.C.H.; Hall, K.D.; Pietrobelli, A.; Sørensen, T.I.A.; Speakman, J.; Trayhurn, P.; Visser, M.; Heymsfield, S.B.

    2014-01-01

    The 12th Stock Conference addressed body composition and related functions in two extreme situations, obesity and cancer cachexia. The concept of “functional body composition” integrates body components into regulatory systems relating the mass of organs and tissues to corresponding in vivo functions and metabolic processes. This concept adds to an understanding of organ/tissue mass and function in the context of metabolic adaptations to weight change and disease. During weight gain and loss there are associated changes in individual body components while the relationships between organ and tissue mass are fixed. Thus, an understanding of weight regulation involves an examination of organ-tissue regulation rather than of individual organ mass. The between organ/tissue mass relationships are associated with and explained by cross-talk between organs and tissues mediated by cytokines, hormones, and metabolites that are coupled with changes in body weight, composition, and function as observed in obesity and cancer cachexia. In addition to established roles in intermediary metabolism, cell function and inflammation, organ-tissue cross-talk mediators are determinants of body composition and its’ change with weight gain and loss. The 12th Stock Conference supported Michael Stocks’ concept of gaining new insights by integrating research ideas from obesity and cancer cachexia. The conference presentations provide an in-depth understanding of body composition and metabolism. PMID:24835453

  11. Age-related effects of body mass on fertility and litter size in roe deer.

    Science.gov (United States)

    Flajšman, Katarina; Jerina, Klemen; Pokorny, Boštjan

    2017-01-01

    We analysed effects of females' body mass and age on reproductive capacity of European roe deer (Capreolus capreolus) in a large sample set of 1312 females (305 yearlings and 1007 adults), hunted throughout Slovenia, central Europe, in the period 2013-2015. Body mass positively affected probability of ovulation and potential litter size (number of corpora lutea), although its effect was more pronounced in yearlings than in adults. Between age groups, we found clear differences in responses of both reproductive parameters to body mass which influences primarily reproductive performance of younger, and in particular, lighter individuals: at the same body mass yearlings would at average have smaller litters than adults, and at lower body mass also young to middle-aged adults would have smaller litters than old ones. In addition, while yearlings have to reach a critical threshold body mass to attain reproductive maturity, adult females are fertile (produce ova) even at low body mass. However, at higher body mass also younger individuals shift their efforts into the reproduction, and after reaching an age-specific threshold the body mass does not have any further effects on the reproductive output of roe deer females. Increased reproductive capacity at more advanced age, combined with declining body mass suggests that old does allocate more of their resources in reproduction than in body condition.

  12. Age-related effects of body mass on fertility and litter size in roe deer.

    Directory of Open Access Journals (Sweden)

    Katarina Flajšman

    Full Text Available We analysed effects of females' body mass and age on reproductive capacity of European roe deer (Capreolus capreolus in a large sample set of 1312 females (305 yearlings and 1007 adults, hunted throughout Slovenia, central Europe, in the period 2013-2015. Body mass positively affected probability of ovulation and potential litter size (number of corpora lutea, although its effect was more pronounced in yearlings than in adults. Between age groups, we found clear differences in responses of both reproductive parameters to body mass which influences primarily reproductive performance of younger, and in particular, lighter individuals: at the same body mass yearlings would at average have smaller litters than adults, and at lower body mass also young to middle-aged adults would have smaller litters than old ones. In addition, while yearlings have to reach a critical threshold body mass to attain reproductive maturity, adult females are fertile (produce ova even at low body mass. However, at higher body mass also younger individuals shift their efforts into the reproduction, and after reaching an age-specific threshold the body mass does not have any further effects on the reproductive output of roe deer females. Increased reproductive capacity at more advanced age, combined with declining body mass suggests that old does allocate more of their resources in reproduction than in body condition.

  13. Selection for growth rate and body size have altered the expression profiles of somatotropic axis genes in chickens

    Science.gov (United States)

    Liu, Yong; Xu, Zhiqiang; Duan, Xiaohua; Li, Qihua; Dou, Tengfei; Gu, Dahai; Rong, Hua; Wang, Kun; Li, Zhengtian; Talpur, Mir Zulqarnain; Huang, Ying; Wang, Shanrong; Yan, Shixiong; Tong, Huiquan; Zhao, Sumei; Zhao, Guiping; Su, Zhengchang; Ge, Changrong

    2018-01-01

    The growth hormone / insulin-like growth factor-1 (GH/IGF-1) pathway of the somatotropic axis is the major controller for growth rate and body size in vertebrates, but the effect of selection on the expression of GH/IGF-1 somatotropic axis genes and their association with body size and growth performance in farm animals is not fully understood. We analyzed a time series of expression profiles of GH/IGF-1 somatotropic axis genes in two chicken breeds, the Daweishan mini chickens and Wuding chickens, and the commercial Avian broilers hybrid exhibiting markedly different body sizes and growth rates. We found that growth rate and feed conversion efficiency in Daweishan mini chickens were significantly lower than those in Wuding chickens and Avian broilers. The Wuding and Daweishan mini chickens showed higher levels of plasma GH, pituitary GH mRNA but lower levels of hepatic growth hormone receptor (GHR) mRNA than in Avian broilers. Daweishan mini chickens showed significantly lower levels of plasma IGF-1, thigh muscle and hepatic IGF-1 mRNA than did Avian broilers and Wuding chickens. These results suggest that the GH part of the somatotropic axis is the main regulator of growth rate, while IGF-1 may regulate both growth rate and body weight. Selection for growth performance and body size have altered the expression profiles of somatotropic axis genes in a breed-, age-, and tissue-specific manner, and manner, and alteration of regulatory mechanisms of these genes might play an important role in the developmental characteristics of chickens. PMID:29630644

  14. GI Joe or Average Joe? The impact of average-size and muscular male fashion models on men's and women's body image and advertisement effectiveness.

    Science.gov (United States)

    Diedrichs, Phillippa C; Lee, Christina

    2010-06-01

    Increasing body size and shape diversity in media imagery may promote positive body image. While research has largely focused on female models and women's body image, men may also be affected by unrealistic images. We examined the impact of average-size and muscular male fashion models on men's and women's body image and perceived advertisement effectiveness. A sample of 330 men and 289 women viewed one of four advertisement conditions: no models, muscular, average-slim or average-large models. Men and women rated average-size models as equally effective in advertisements as muscular models. For men, exposure to average-size models was associated with more positive body image in comparison to viewing no models, but no difference was found in comparison to muscular models. Similar results were found for women. Internalisation of beauty ideals did not moderate these effects. These findings suggest that average-size male models can promote positive body image and appeal to consumers. 2010 Elsevier Ltd. All rights reserved.

  15. Twin study of genetic and environmental influences on adult body size, shape and composition

    DEFF Research Database (Denmark)

    Schousboe, K.; Visscher, P.M.; Erbas, B.

    2004-01-01

    ), we determined zygosity by DNA similarity, and performed anthropometry and bioelectrical impedance analysis of body composition. The contribution to the total phenotypic variance of genetic, common environment, and individual environment was estimated in multivariate analysis using the FISHER program...... effects under the assumptions of no nonadditive effect. The pattern of age trends was inconsistent. However, when significant there was a decrease in heritability with advancing age. DISCUSSION: These findings suggest that adult body size, shape, and composition are highly heritable in both women and men...

  16. The effect of feeding position and body size on the capacity of small ...

    African Journals Online (AJOL)

    The effect of feeding position and body size on the capacity of small ruminants to reach, for food when fed through barriers. ... The barrier allowed the neck to pass through, but not the shoulders. It was hypothesized that goats would have larger reach than sheep and that for each species, horizontal reach forwards, F, ...

  17. Scale effects between body size and limb design in quadrupedal mammals.

    Science.gov (United States)

    Kilbourne, Brandon M; Hoffman, Louwrens C

    2013-01-01

    Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties--limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency--were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass(0.40)); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass(1.0)), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb's potential for angular acceleration scales according to geometric similarity, whereas the hindlimb's potential for angular acceleration scales with positive allometry.

  18. Platelet size and age determine platelet function independently

    International Nuclear Information System (INIS)

    Thompson, C.B.; Jakubowski, J.A.; Quinn, P.G.; Deykin, D.; Valeri, C.R.

    1984-01-01

    A study was undertaken to examine the interaction of platelet size and age in determining in vitro platelet function. Baboon megakaryocytes were labeled in vivo by the injection of 75Se-methionine. Blood was collected when the label was predominantly associated with younger platelets (day 2) and with older platelets (day 9). Size-dependent platelet subpopulations were prepared on both days by counterflow centrifugation. The reactivity of each platelet subpopulation was determined on both days by measuring thrombin-induced aggregation. Platelets were fixed after partial aggregation had occurred by the addition of EDTA/formalin. After removal of the aggregated platelets by differential centrifugation, the supernatant medium was assayed for remaining platelets and 75Se radioactivity. Comparing day 2 and day 9, no significant difference was seen in the rate of aggregation of a given subpopulation. However, aggregation was more rapid in the larger platelet fractions than in the smaller ones on both days. A greater percentage of the 75Se radioactivity appeared in the platelet aggregates on day 2 than on day 9. This effect was independent of platelet size, as it occurred to a similar extent in the unfractionated platelets and in each of the size-dependent platelet subpopulations. The data indicate that young platelets are more active than older platelets. This study demonstrates that size and age are both determinants of platelet function, but by independent mechanisms

  19. Resolving Microzooplankton Functional Groups In A Size-Structured Planktonic Model

    Science.gov (United States)

    Taniguchi, D.; Dutkiewicz, S.; Follows, M. J.; Jahn, O.; Menden-Deuer, S.

    2016-02-01

    Microzooplankton are important marine grazers, often consuming a large fraction of primary productivity. They consist of a great diversity of organisms with different behaviors, characteristics, and rates. This functional diversity, and its consequences, are not currently reflected in large-scale ocean ecological simulations. How should these organisms be represented, and what are the implications for their biogeography? We develop a size-structured, trait-based model to characterize a diversity of microzooplankton functional groups. We compile and examine size-based laboratory data on the traits, revealing some patterns with size and functional group that we interpret with mechanistic theory. Fitting the model to the data provides parameterizations of key rates and properties, which we employ in a numerical ocean model. The diversity of grazing preference, rates, and trophic strategies enables the coexistence of different functional groups of micro-grazers under various environmental conditions, and the model produces testable predictions of the biogeography.

  20. Body size of young Australians aged five to 16 years.

    Science.gov (United States)

    Hitchcock, N E; Maller, R A; Gilmour, A I

    1986-10-20

    In 1983-1984, 4578 Perth primary and secondary schoolchildren were studied. The selected sample was broadly representative of the ethnic groups that make up the Perth population and of the different social ranks within that population. The age, sex, weight, height, country of birth of the child and the parents, and occupation of the father were recorded for each subject. Weight, height and body mass index (BMI) increased with age. Age and sex were the most important determinants of body size. However, children of lower social rank and those with a southern European background were over-represented among the overweight children (greater than the 90th centile for BMI), particularly in adolescence. Children with an Asian background who were 11 years of age and younger were over-represented among the underweight children (less than or equal to the 10th centile for BMI). Results from this study indicate a continuing, though small (1.5 cm to 1.6 cm), secular increase in height over the past 13 to 14 years.

  1. Contest experience and body size affect different types of contest decisions.

    Science.gov (United States)

    Chen, Yu-Ju; Hsu, Yuying

    2016-11-01

    This study examined the relative importance of contest experience and size differences to behavioral decisions over the course of contests. Using a mangrove rivulus fish, Kryptolebias marmoratus, we showed that although contest experience and size differences jointly determined contest outcomes, they affected contestants' interactions at different stages of contests. Contest experience affected behavioral decisions at earlier stages of contests, including the tendency and latency to launch attacks, the tendency to escalate contests into mutual attacks and the outcome of non-escalated contests. Once contests were escalated into mutual attacks, the degree of size difference affected the fish's persistence in escalation and chance of winning, but contest experience did not. These results support the hypothesis that contest experience modifies individuals' estimation of their fighting ability rather than their actual strength. Furthermore, (1) in contests between two naïve contestants, more than 60 % of fish that were 2-3 mm smaller than their opponent escalated the contest to physical fights, even though their larger opponents eventually won 92 % of escalated fights and (2) fish with a losing experience were very likely to retreat in the face of an opponent 2-3 mm smaller than them without escalating. The result that a 2-3 mm size advantage could not offset the influence of a losing experience on the tendency to escalate suggests that, as well as depending on body size, the fish's physical strength is influenced by other factors which require further investigation.

  2. Relationship between Psychosocial Functioning and Body Fat in Preschool Children: A Longitudinal Investigation.

    Science.gov (United States)

    Klesges, Robert C.; And Others

    1992-01-01

    Examined whether 132 preschool children who varied in levels of body fat differed on psychosocial functioning. Children did not differ in self-esteem and family functioning as function of body fat. Prospectively, physical self-esteem weakly but significantly correlated with body fat at one and two years; father's perception of family functioning…

  3. Body Dysmorphic Symptoms, Functional Impairment, and Depression: The Role of Appearance-Based Teasing.

    Science.gov (United States)

    Weingarden, Hilary; Renshaw, Keith D

    2016-01-01

    Body dysmorphic disorder is associated with elevated social and occupational impairment and comorbid depression, but research on risk factors for body dysmorphic symptoms and associated outcomes is limited. Appearance-based teasing may be a potential risk factor. To examine the specificity of this factor, the authors assessed self-reported appearance-based teasing, body dysmorphic, and obsessive-compulsive symptom severity, functional impairment (i.e., social, occupational, family impairment), and depression in a nonclinical sample of undergraduates. As hypothesized, appearance-based teasing was positively correlated with body dysmorphic symptoms. The correlation between teasing and body dysmorphic symptoms was stronger than that between teasing and obsessive-compulsive symptom severity. Last, body dysmorphic symptom severity and appearance-based teasing interacted in predicting functional impairment and depression. Specifically, appearance-based teasing was positively associated with depression and functional impairment only in those with elevated body dysmorphic symptoms. When a similar moderation was tested with obsessive-compulsive, in place of body dysmorphic, symptom severity, the interaction was nonsignificant. Findings support theory that appearance-based teasing is a specific risk factor for body dysmorphic symptoms and associated functional impairment.

  4. Embodiment in a Child-Like Talking Virtual Body Influences Object Size Perception, Self-Identification, and Subsequent Real Speaking.

    Science.gov (United States)

    Tajadura-Jiménez, Ana; Banakou, Domna; Bianchi-Berthouze, Nadia; Slater, Mel

    2017-08-29

    People's mental representations of their own body are malleable and continuously updated through sensory cues. Altering one's body-representation can lead to changes in object perception and implicit attitudes. Virtual reality has been used to embody adults in the body of a 4-year-old child or a scaled-down adult body. Child embodiment was found to cause an overestimation of object sizes, approximately double that during adult embodiment, and identification of the self with child-like attributes. Here we tested the contribution of auditory cues related to one's own voice to these visually-driven effects. In a 2 × 2 factorial design, visual and auditory feedback on one's own body were varied across conditions, which included embodiment in a child or scaled-down adult body, and real (undistorted) or child-like voice feedback. The results replicated, in an older population, previous findings regarding size estimations and implicit attitudes. Further, although auditory cues were not found to enhance these effects, we show that the strength of the embodiment illusion depends on the child-like voice feedback being congruent or incongruent with the age of the virtual body. Results also showed the positive emotional impact of the illusion of owning a child's body, opening up possibilities for health applications.

  5. Firm size diversity, functional richness, and resilience

    Science.gov (United States)

    Garmestani, A.S.; Allen, Craig R.; Mittelstaedt, J.D.; Stow, C.A.; Ward, W.A.

    2006-01-01

    This paper applies recent advances in ecology to our understanding of firm development, sustainability, and economic development. The ecological literature indicates that the greater the functional richness of species in a system, the greater its resilience - that is, its ability to persist in the face of substantial changes in the environment. This paper focuses on the effects of functional richness across firm size on the ability of industries to survive in the face of economic change. Our results indicate that industries with a richness of industrial functions are more resilient to employment volatility. ?? 2006 Cambridge University Press.

  6. Relationship between self-discrepancy and worries about penis size in men with body dysmorphic disorder.

    Science.gov (United States)

    Veale, David; Miles, Sarah; Read, Julie; Bramley, Sally; Troglia, Andrea; Carmona, Lina; Fiorito, Chiara; Wells, Hannah; Wylie, Kevan; Muir, Gordon

    2016-06-01

    We explored self-discrepancy in men with body dysmorphic disorder (BDD) concerned about penis size, men without BDD but anxious about penis size, and controls. Men with BDD (n=26) were compared to those with small penis anxiety (SPA; n=31) and controls (n=33), objectively (by measuring) and investigating self-discrepancy: actual size, ideal size, and size they felt they should be according to self and other. Most men under-estimated their penis size, with the BDD group showing the greatest discrepancy between perceived and ideal size. The SPA group showed a larger discrepancy than controls. This was replicated for the perceptions of others, suggesting the BDD group internalised the belief that they should have a larger penis size. There was a significant correlation between symptoms of BDD and this discrepancy. This self-actual and self-ideal/self-should discrepancy and the role of comparing could be targeted in therapy. Copyright © 2016. Published by Elsevier Ltd.

  7. No support for Heincke's law in hagfish (Myxinidae): lack of an association between body size and the depth of species occurrence.

    Science.gov (United States)

    Schumacher, E L; Owens, B D; Uyeno, T A; Clark, A J; Reece, J S

    2017-08-01

    This study tests for interspecific evidence of Heincke's law among hagfishes and advances the field of research on body size and depth of occurrence in fishes by including a phylogenetic correction and by examining depth in four ways: maximum depth, minimum depth, mean depth of recorded specimens and the average of maximum and minimum depths of occurrence. Results yield no evidence for Heincke's law in hagfishes, no phylogenetic signal for the depth at which species occur, but moderate to weak phylogenetic signal for body size, suggesting that phylogeny may play a role in determining body size in this group. © 2017 The Fisheries Society of the British Isles.

  8. Intra- and Trans-Generational Costs of Reduced Female Body Size Caused by Food Limitation Early in Life in Mites

    OpenAIRE

    Walzer, Andreas; Schausberger, Peter

    2013-01-01

    Background Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Methodology/Principal Findings Here, we evaluated the costs of small female body size induced by food limitation early in life i...

  9. Sizing for ethnicity in multi-cultural societies: development of size ...

    African Journals Online (AJOL)

    ... years, and fell in the size 6/10 to size 14/38 size range. The findings of the study suggest that young South African women of African descent with a triangular body shape may experience loose fit in the upper body of garments sized according to the size specifications currently used in the South African apparel industry.

  10. Many-Body Green Function of Degenerate Systems

    International Nuclear Information System (INIS)

    Brouder, Christian; Panati, Gianluca; Stoltz, Gabriel

    2009-01-01

    A rigorous nonperturbative adiabatic approximation of the evolution operator in the many-body physics of degenerate systems is derived. This approximation is used to solve the long-standing problem of the choice of the initial states of H 0 leading to eigenstates of H 0 +V for degenerate systems. These initial states are eigenstates of P 0 VP 0 , where P 0 is the projection onto a degenerate eigenspace of H 0 . This result is used to give the proper definition of the Green function, the statistical Green function and the nonequilibrium Green function of degenerate systems. The convergence of these Green functions is established.

  11. Distribution and linkage disequilibrium analysis of polymorphisms of GH1 gene in different populations of pigs associated with body size.

    Science.gov (United States)

    Cheng, Yunyun; Liu, Songcai; Su, Dan; Lu, Chao; Zhang, Xin; Wu, Qingyan; Li, Siming; Fu, Haoyu; Yu, Hao; Hao, Linlin

    2016-03-01

    Growth hormone (GH) has been considered as a candidate gene for growth and body size in pigs. In this study, polymorphisms of the GH1 gene were evaluated for associations with body size traits in 190 pig individuals. Seventeen single-nucleotide polymorphisms (SNPs) were identified in GH1 gene of the large pig breeds and miniature pig breeds using direct sequencing and genotyped by allele-specific PCR approach. Notably, six (g.237A>G, g.283T>C, g.309A>G, g.318A>G, g.540A>G and g.544A>G) of them were significantly associated with body size, of which three loci (g.283T>C, g.309A>G, g.318A>G) located in the signal-peptide coding region of GH1 gene compose a CGG haplotype for large pigs and TAA haplotype for miniature pigs (P G and g.544A>G) located in the second intron of GH1 gene compose a GG haplotype for large pigs and AA haplotype for miniature pigs (P body size of pigs providing genetic basis for pig breeding with the improved economic benefits.

  12. Body size and shape misperception and visual adaptation: An overview of an emerging research paradigm.

    Science.gov (United States)

    Challinor, Kirsten L; Mond, Jonathan; Stephen, Ian D; Mitchison, Deborah; Stevenson, Richard J; Hay, Phillipa; Brooks, Kevin R

    2017-12-01

    Although body size and shape misperception (BSSM) is a common feature of anorexia nervosa, bulimia nervosa and muscle dysmorphia, little is known about its underlying neural mechanisms. Recently, a new approach has emerged, based on the long-established non-invasive technique of perceptual adaptation, which allows for inferences about the structure of the neural apparatus responsible for alterations in visual appearance. Here, we describe several recent experimental examples of BSSM, wherein exposure to "extreme" body stimuli causes visual aftereffects of biased perception. The implications of these studies for our understanding of the neural and cognitive representation of human bodies, along with their implications for clinical practice are discussed.

  13. Microclimatic Divergence in a Mediterranean Canyon Affects Richness, Composition, and Body Size in Saproxylic Beetle Assemblages.

    Directory of Open Access Journals (Sweden)

    Jörn Buse

    Full Text Available Large valleys with opposing slopes may act as a model system with which the effects of strong climatic gradients on biodiversity can be evaluated. The advantage of such comparisons is that the impact of a change of climate can be studied on the same species pool without the need to consider regional differences. The aim of this study was to compare the assemblage of saproxylic beetles on such opposing slopes at Lower Nahal Oren, Mt. Carmel, Israel (also known as "Evolution Canyon" with a 200-800% higher solar radiation on the south-facing (SFS compared to the north-facing slope (NFS. We tested specific hypotheses of species richness patterns, assemblage structure, and body size resulting from interslope differences in microclimate. Fifteen flight-interception traps per slope were distributed over three elevation levels ranging from 50 to 100 m a.s.l. Richness of saproxylic beetles was on average 34% higher on the SFS compared with the NFS, with no detected influence of elevation levels. Both assemblage structure and average body size were determined by slope aspect, with more small-bodied beetles found on the SFS. Both the increase in species richness and the higher prevalence of small species on the SFS reflect ecological rules present on larger spatial grain (species-energy hypothesis and community body size shift hypothesis, and both can be explained by the metabolic theory of ecology. This is encouraging for the complementary use of micro- and macroclimatic gradients to study impacts of climate warming on biodiversity.

  14. Associations between adiposity, hormones, and gains in height, whole-body height-adjusted bone size, and size-adjusted bone mineral content in 8- to 11-year-old children

    DEFF Research Database (Denmark)

    Dalskov, Stine-Mathilde; Ritz, Christian; Larnkjær, Anni

    2016-01-01

    We examined fat-independent associations of hormones with height and whole-body bone size and mineral content in 633 school children. IGF-1 and osteocalcin predict growth in height, while fat, osteocalcin, and in girls also, IGF-1 predict growth in bone size. Leptin and ghrelin are inversely asso...

  15. Effects of Isometric Brain-Body Size Scaling on the Complexity of Monoaminergic Neurons in a Minute Parasitic Wasp

    NARCIS (Netherlands)

    Woude, van der Emma; Smid, Hans M.

    2017-01-01

    Trichogramma evanescens parasitic wasps show large phenotypic plasticity in brain and body size, resulting in a 5-fold difference in brain volume among genetically identical sister wasps. Brain volume scales linearly with body volume in these wasps. This isometric brain scaling forms an exception to

  16. A sex-specific trade-off between mating preferences for genetic compatibility and body size in a cichlid fish with mutual mate choice.

    Science.gov (United States)

    Thünken, Timo; Meuthen, Denis; Bakker, Theo C M; Baldauf, Sebastian A

    2012-08-07

    Mating preferences for genetic compatibility strictly depend on the interplay of the genotypes of potential partners and are therein fundamentally different from directional preferences for ornamental secondary sexual traits. Thus, the most compatible partner is on average not the one with most pronounced ornaments and vice versa. Hence, mating preferences may often conflict. Here, we present a solution to this problem while investigating the interplay of mating preferences for relatedness (a compatibility criterion) and large body size (an ornamental or quality trait). In previous experiments, both sexes of Pelvicachromis taeniatus, a cichlid fish with mutual mate choice, showed preferences for kin and large partners when these criteria were tested separately. In the present study, test fish were given a conflicting choice between two potential mating partners differing in relatedness as well as in body size in such a way that preferences for both criteria could not simultaneously be satisfied. We show that a sex-specific trade-off occurs between mating preferences for body size and relatedness. For females, relatedness gained greater importance than body size, whereas the opposite was true for males. We discuss the potential role of the interplay between mating preferences for relatedness and body size for the evolution of inbreeding preference.

  17. Variation in male body size and reproductive allocation in the leafcutter ant Atta colombica

    DEFF Research Database (Denmark)

    Stürup, M.; den Boer, S. P. A.; Nash, David Richard

    2011-01-01

    species. In 2008 and 2009, we revisited a Panamanian population of Atta colombica leafcutter ants to partially repeat and complement a study of more than 15 years ago. We compared within- and between-colony variation in male body size (mass and width of head, mesosoma and gaster) and sperm characteristics...

  18. Ontogenetic functional diversity: size structure of a keystone predator drives functioning of a complex ecosystem.

    Science.gov (United States)

    Rudolf, Volker H W; Rasmussen, Nick L

    2013-05-01

    A central challenge in community ecology is to understand the connection between biodiversity and the functioning of ecosystems. While traditional approaches have largely focused on species-level diversity, increasing evidence indicates that there exists substantial ecological diversity among individuals within species. By far, the largest source of this intraspecific diversity stems from variation among individuals in ontogenetic stage and size. Although such ontogenetic shifts are ubiquitous in natural communities, whether and how they scale up to influence the structure and functioning of complex ecosystems is largely unknown. Here we take an experimental approach to examine the consequences of ontogenetic niche shifts for the structure of communities and ecosystem processes. In particular we experimentally manipulated the stage structure in a keystone predator, larvae of the dragonfly Anax junius, in complex experimental pond communities to test whether changes in the population stage or size structure of a keystone species scale up to alter community structure and ecosystem processes, and how functional differences scale with relative differences in size among stages. We found that the functional role of A. junius was stage-specific. Altering what stages were present in a pond led to concurrent changes in community structure, primary producer biomass (periphyton and phytoplankton), and ultimately altered ecosystem processes (respiration and net primary productivity), indicating a strong, but stage-specific, trophic cascade. Interestingly, the stage-specific effects did not simply scale with size or biomass of the predator, but instead indicated clear ontogenetic niche shifts in ecological interactions. Thus, functional differences among stages within a keystone species scaled up to alter the functioning of entire ecosystems. Therefore, our results indicate that the classical approach of assuming an average functional role of a species can be misleading because

  19. Influence of body size on Cu bioaccumulation in zebra mussels Dreissena polymorpha exposed to different sources of particle-associated Cu

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Huan, E-mail: huanzhong1982@hotmail.com [Environmental and Resource Studies Program, Trent University, Peterborough, Ontario (Canada); Nanjing University, School of Environment, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing, Jiangsu Province (China); Kraemer, Lisa; Evans, Douglas [Environmental and Resource Studies Program, Trent University, Peterborough, Ontario (Canada)

    2013-10-15

    Highlights: • Mussels exposed to algal/sediment-Cu have different size-related Cu accumulation. • Size-related Cu accumulation in mussels could be more dependant on algal-Cu uptake. • Importance of algal/sediment-Cu to Cu bioaccumulation varies with mussel body size. • Cu sources (algae and sediments) should be considered in “mussel watch” programs. • Cu stable isotope offers many advantages in Cu bioaccumulation studies. -- Abstract: Size of organisms is critical in controlling metal bioavailability and bioaccumulation, while mechanisms of size-related metal bioaccumulation are not fully understood. To investigate the influences of different sources of particle-associated Cu on body size-related Cu bioavailability and bioaccumulation, zebra mussels (Dreissena polymorpha) of different sizes were exposed to stable Cu isotope ({sup 65}Cu) spiked algae (Chlorella vulgaris) or sediments in the laboratory and the Cu tissue concentration-size relationships were compared with that in unexposed mussels. Copper tissue concentrations decreased with mussel size (tissue or shell dry weight) in both unexposed and algal-exposed mussels with similar decreasing patterns, but were independent of size in sediment-exposed mussels. Furthermore, the relative contribution of Cu uptake from algae (65–91%) to Cu bioaccumulation is always higher than that from sediments (9–35%), possibly due to the higher bioavailability of algal-Cu. Therefore, the size-related ingestion of algae could be more important in influencing the size-related variations in Cu bioaccumulation. However, the relative contribution of sediment-Cu to Cu bioaccumulation increased with body size and thus sediment ingestion may also affect the size-related Cu variations in larger mussels (tissue weight >7.5 mg). This study highlights the importance of considering exposure pathways in normalization of metal concentration variation when using bivalves as biomonitors.

  20. Modeling response of species to microcontaminants: comparative ecotoxicology by (sub)lethal body burdens as a function of species size and partition ratio of chemicals.

    Science.gov (United States)

    Hendriks, A J

    1995-11-01

    A model was designed and calibrated with accumulation data to calculate the internal concentrations of microcontaminants in organisms as a function of a few constants and variables. The main factors are the exposure time, the external exposure concentration, the partition ratio of the compound, and the size of the taxon concerned. The model was applied to calculate the lethal and sublethal body burdens of several priority compounds and some major taxa. Estimations were generally confirmed at the order of magnitude level by measured residues and applied doses if available. According to the estimations, most priority compounds chosen were critical for most taxa above internal concentrations of 0.1 mmol.kg-1 wet wt. Trichloromethane, 1,2,4-trichlorobenzene, and hexachlorobenzene were lethal above this level only, whereas other organic microcontaminants affected at least some taxa at lower body burdens. The log(Kow) of the organic compounds ranged from 2.0 to 7.0. Keeping in mind that bioconcentration and -magnification ratios for metals may be quite variable, the lowest critical residues estimated were just below the value of 0.1 mmol.kg-1 wet wt. Here, external concentrations encountered in natural habitats seem to be a promising tool for predictive comparative ecotoxicology. The critical body burdens for plants and invertebrates may have been overestimated due to uncertainty about the parameters. Among the different taxa, however, the fish families chosen (Salmonidae and Cyprinidae) seem to be most sensitive to most compounds. Internal response concentrations of the herbicide atrazine were the lowest in micro- and macrophytes, whereas parathion affected invertebrates at low levels. The database that provided the external response concentrations was also consulted to estimate so-called extrapolation or safety factors. On average, long-term no effect concentrations in water are estimated to be about 10-30 times below short-term median lethal levels. In general, short

  1. Size Evolution and Stochastic Models: Explaining Ostracod Size through Probabilistic Distributions

    Science.gov (United States)

    Krawczyk, M.; Decker, S.; Heim, N. A.; Payne, J.

    2014-12-01

    The biovolume of animals has functioned as an important benchmark for measuring evolution throughout geologic time. In our project, we examined the observed average body size of ostracods over time in order to understand the mechanism of size evolution in these marine organisms. The body size of ostracods has varied since the beginning of the Ordovician, where the first true ostracods appeared. We created a stochastic branching model to create possible evolutionary trees of ostracod size. Using stratigraphic ranges for ostracods compiled from over 750 genera in the Treatise on Invertebrate Paleontology, we calculated overall speciation and extinction rates for our model. At each timestep in our model, new lineages can evolve or existing lineages can become extinct. Newly evolved lineages are assigned sizes based on their parent genera. We parameterized our model to generate neutral and directional changes in ostracod size to compare with the observed data. New sizes were chosen via a normal distribution, and the neutral model selected new sizes differentials centered on zero, allowing for an equal chance of larger or smaller ostracods at each speciation. Conversely, the directional model centered the distribution on a negative value, giving a larger chance of smaller ostracods. Our data strongly suggests that the overall direction of ostracod evolution has been following a model that directionally pushes mean ostracod size down, shying away from a neutral model. Our model was able to match the magnitude of size decrease. Our models had a constant linear decrease while the actual data had a much more rapid initial rate followed by a constant size. The nuance of the observed trends ultimately suggests a more complex method of size evolution. In conclusion, probabilistic methods can provide valuable insight into possible evolutionary mechanisms determining size evolution in ostracods.

  2. Supplementing five-point body condition score with body fat percentage increases the sensitivity for assessing overweight status of small to medium sized dogs

    Directory of Open Access Journals (Sweden)

    Arai T

    2012-09-01

    Full Text Available Gebin Li,1 Peter Lee,1 Nobuko Mori,1 Ichiro Yamamoto,1 Koh Kawasumi,1 Hisao Tanabe,2 Toshiro Arai11Department of Veterinary Science, School of Veterinary Medicine, Nippon Veterinary and Life Science University, 2Komazawa Animal Hospital, Tokyo, JapanBackground and methods: Currently, five-point body condition scoring (BCS is widely used by veterinarians and clinicians to assess adiposity in dogs in Japan. However, BCS score assignment is subjective in nature, and most clinicians do not score with half points, instead preferring to round off values, thereby rendering less accurate assessments. Therefore, we sought to determine whether assessing body fat percentage using simple morphometric measurements and supplementing this with five-point BCS can have increased sensitivity for detecting increasing adiposity in overweight small-medium sized dog breeds via plasma metabolite validation.Results: Overall, lean body fat percentage was determined to be 15%–22% for male (non-neutered/neutered dogs and 15%–25% for female (nonspayed/spayed. Dogs categorized as overweight by BCS had significantly higher levels of nonesterified fatty acids (P = 0.005, whereas animals categorized as overweight by BCS + body fat percentage were observed to have significantly higher levels of nonesterified fatty acids (P = 0.006, total cholesterol (P = 0.029, and triglycerides (P = 0.001 than lean animals. The increased sensitivity due to body fat percentage for gauging alterations in plasma metabolite levels may be due to increased correlation strength. Body fat percentage correlated positively with plasma insulin (r = 0.627, P = 0.002, nonesterified fatty acids (r = 0.674, P < 0.001, total cholesterol (r = 0.825, P < 0.0001, triglycerides (r = 0.5823, P < 0.005, blood urea nitrogen (r = 0.429, P < 0.05, creatinine (r = 0.490, P = 0.021, and total protein (r = 0.737, P< 0.0001 levels, which all tend to increase as a result of increasing adiposity

  3. Classical density functional theory and the phase-field crystal method using a rational function to describe the two-body direct correlation function.

    Science.gov (United States)

    Pisutha-Arnond, N; Chan, V W L; Iyer, M; Gavini, V; Thornton, K

    2013-01-01

    We introduce a new approach to represent a two-body direct correlation function (DCF) in order to alleviate the computational demand of classical density functional theory (CDFT) and enhance the predictive capability of the phase-field crystal (PFC) method. The approach utilizes a rational function fit (RFF) to approximate the two-body DCF in Fourier space. We use the RFF to show that short-wavelength contributions of the two-body DCF play an important role in determining the thermodynamic properties of materials. We further show that using the RFF to empirically parametrize the two-body DCF allows us to obtain the thermodynamic properties of solids and liquids that agree with the results of CDFT simulations with the full two-body DCF without incurring significant computational costs. In addition, the RFF can also be used to improve the representation of the two-body DCF in the PFC method. Last, the RFF allows for a real-space reformulation of the CDFT and PFC method, which enables descriptions of nonperiodic systems and the use of nonuniform and adaptive grids.

  4. [Prevalence of depression and body dysmorphic disorder in patients before functional rhinosurgery].

    Science.gov (United States)

    Bender, M; Rustige, L; Lindemann, J

    2014-11-01

    Psychiatric disorders are known to influence the result of many surgical procedures. Body dysmorphic disorder (BDD) is found in many patients undergoing plastic surgery. The prevalence before functional rhinosurgery has not been examined so far. The aim of this study was to determine the prevalence of depression and BDD before functional rhinosurgery. 201 patients were prospectively examined with a questionnaire before functional rhinosurgery. Beck-Depression-Index was used to rate depression, the PISA body dsymorphic symptom scale was used to evaluate the likelihood that a patient suffers from body dysmoprhic disorder. 186 patients returned a complete questionnaire. In 33.9% showed a mild or strong indication for a body dysmorphic disorder. Patients who were planned to undergo septorhinoplasty had a significantly higher scores in the PISA-scale compared to patients before septoplasty. 1.7% patients were depressive without a significant difference between the planned surgical procedure. Many patients before functional septorhinoplasty show signs of body dysmorphic disorder. Whether this influences the subjective clinical outcome needs to be evaluated in further studies. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Despite Buffers, Experimental Forest Clearcuts Impact Amphibian Body Size and Biomass.

    Science.gov (United States)

    Veysey Powell, Jessica S; Babbitt, Kimberly J

    2015-01-01

    Forest buffers are a primary tool used to protect wetland-dependent wildlife. Though implemented widely, buffer efficacy is untested for most amphibian species. Consequently, it remains unclear whether buffers are sufficient for maintaining amphibian populations and if so, how wide buffers should be. We present evidence from a six-year, landscape-scale experiment testing the impacts of clearcutting, buffer width, and hydroperiod on body size and condition and biomass of breeding adults for two amphibian species at 11 vernal pools in the northeastern United States. We randomly assigned treatments (i.e., reference, 100m buffer, 30m buffer) across pools, clearcut to create buffers, and captured all spotted salamanders and wood frogs. Clearcuts strongly and negatively impacted size, condition, and biomass, but wider buffers mitigated effect magnitude and duration. Among recaptured individuals, for example, 30m-treatment salamanders were predicted to be about 9.5 mm shorter than, while 100m-treatment salamanders did not differ in length from, reference-treatment salamanders. Similarly, among recaptured frogs, mean length in the 30m treatment was predicted to decrease by about 1 mm/year, while in the 100m and reference treatments, length was time-invariant. Some, but not all, metrics recovered with time. For example, female new-captured and recaptured salamanders were predicted, respectively and on average, to weigh 4.5 and 7 g less in the 30m versus reference treatment right after the cut. While recaptured-female mass was predicted to recover by 9.5 years post-cut, new-captured-female mass did not recover. Hydroperiod was an important mediator: in the 100m treatment, cutting predominately affected pools that were stressed hydrologically. Overall, salamanders and female frogs were impacted more than male frogs. Our results highlight the importance of individualized metrics like body size, which can reveal sublethal effects and illuminate mechanisms by which habitat

  6. Despite Buffers, Experimental Forest Clearcuts Impact Amphibian Body Size and Biomass.

    Directory of Open Access Journals (Sweden)

    Jessica S Veysey Powell

    Full Text Available Forest buffers are a primary tool used to protect wetland-dependent wildlife. Though implemented widely, buffer efficacy is untested for most amphibian species. Consequently, it remains unclear whether buffers are sufficient for maintaining amphibian populations and if so, how wide buffers should be. We present evidence from a six-year, landscape-scale experiment testing the impacts of clearcutting, buffer width, and hydroperiod on body size and condition and biomass of breeding adults for two amphibian species at 11 vernal pools in the northeastern United States. We randomly assigned treatments (i.e., reference, 100m buffer, 30m buffer across pools, clearcut to create buffers, and captured all spotted salamanders and wood frogs. Clearcuts strongly and negatively impacted size, condition, and biomass, but wider buffers mitigated effect magnitude and duration. Among recaptured individuals, for example, 30m-treatment salamanders were predicted to be about 9.5 mm shorter than, while 100m-treatment salamanders did not differ in length from, reference-treatment salamanders. Similarly, among recaptured frogs, mean length in the 30m treatment was predicted to decrease by about 1 mm/year, while in the 100m and reference treatments, length was time-invariant. Some, but not all, metrics recovered with time. For example, female new-captured and recaptured salamanders were predicted, respectively and on average, to weigh 4.5 and 7 g less in the 30m versus reference treatment right after the cut. While recaptured-female mass was predicted to recover by 9.5 years post-cut, new-captured-female mass did not recover. Hydroperiod was an important mediator: in the 100m treatment, cutting predominately affected pools that were stressed hydrologically. Overall, salamanders and female frogs were impacted more than male frogs. Our results highlight the importance of individualized metrics like body size, which can reveal sublethal effects and illuminate mechanisms by

  7. Size-appropriate radiation doses in pediatric body CT: a study of regional community adoption in the United States

    International Nuclear Information System (INIS)

    Hopkins, Katharine L.; Vajtai, Petra L.; Pettersson, David R.; Spinning, Kristopher; Beckett, Brooke R.; Koudelka, Caroline W.; Bardo, Dianna M.E.

    2013-01-01

    During the last decade, there has been a movement in the United States toward utilizing size-appropriate radiation doses for pediatric body CT, with smaller doses given to smaller patients. This study assesses community adoption of size-appropriate pediatric CT techniques. Size-specific dose estimates (SSDE) in pediatric body scans are compared between community facilities and a university children's hospital that tailors CT protocols to patient size as advocated by Image Gently. We compared 164 pediatric body scans done at community facilities (group X) with 466 children's hospital scans. Children's hospital scans were divided into two groups: A, 250 performed with established pediatric weight-based protocols and filtered back projection; B, 216 performed with addition of iterative reconstruction technique and a 60% reduction in volume CT dose index (CTDI vol ). SSDE was calculated and differences among groups were compared by regression analysis. Mean SSDE was 1.6 and 3.9 times higher in group X than in groups A and B and 2.5 times higher for group A than group B. A model adjusting for confounders confirmed significant differences between group pairs. Regional community hospitals and imaging centers have not universally adopted child-sized pediatric CT practices. More education and accountability may be necessary to achieve widespread implementation. Since even lower radiation doses are possible with iterative reconstruction technique than with filtered back projection alone, further exploration of the former is encouraged. (orig.)

  8. Size-appropriate radiation doses in pediatric body CT: a study of regional community adoption in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, Katharine L.; Vajtai, Petra L. [Oregon Health and Science University, Department of Diagnostic Radiology, DC7R, Portland, OR (United States); Oregon Health and Science University, Department of Pediatrics, Portland, OR (United States); Pettersson, David R.; Spinning, Kristopher; Beckett, Brooke R. [Oregon Health and Science University, Department of Diagnostic Radiology, DC7R, Portland, OR (United States); Koudelka, Caroline W. [Oregon Health and Science University, Division of Biostatistics, Department of Public Health and Preventive Medicine, Portland, OR (United States); Bardo, Dianna M.E. [Oregon Health and Science University, Department of Diagnostic Radiology, DC7R, Portland, OR (United States); Oregon Health and Science University, Department of Cardiovascular Medicine, Portland, OR (United States)

    2013-09-15

    During the last decade, there has been a movement in the United States toward utilizing size-appropriate radiation doses for pediatric body CT, with smaller doses given to smaller patients. This study assesses community adoption of size-appropriate pediatric CT techniques. Size-specific dose estimates (SSDE) in pediatric body scans are compared between community facilities and a university children's hospital that tailors CT protocols to patient size as advocated by Image Gently. We compared 164 pediatric body scans done at community facilities (group X) with 466 children's hospital scans. Children's hospital scans were divided into two groups: A, 250 performed with established pediatric weight-based protocols and filtered back projection; B, 216 performed with addition of iterative reconstruction technique and a 60% reduction in volume CT dose index (CTDI{sub vol}). SSDE was calculated and differences among groups were compared by regression analysis. Mean SSDE was 1.6 and 3.9 times higher in group X than in groups A and B and 2.5 times higher for group A than group B. A model adjusting for confounders confirmed significant differences between group pairs. Regional community hospitals and imaging centers have not universally adopted child-sized pediatric CT practices. More education and accountability may be necessary to achieve widespread implementation. Since even lower radiation doses are possible with iterative reconstruction technique than with filtered back projection alone, further exploration of the former is encouraged. (orig.)

  9. Body size, physical activity and risk of colorectal cancer with or without the CpG island methylator phenotype (CIMP.

    Directory of Open Access Journals (Sweden)

    Laura A E Hughes

    Full Text Available BACKGROUND: We investigated how body size and physical activity influence the risk of the CpG island methylator phenotype (CIMP in colorectal cancer (CRC. METHODS: In the Netherlands Cohort Study (n = 120,852, risk factors were self-reported at baseline in 1986. After 7.3 years of follow-up, 603 cases and 4,631 sub-cohort members were available. CIMP status according to the Weisenberger markers was determined using methylation specific PCR on DNA from paraffin embedded tumor tissue. Hazard rate ratios (HR and 95% confidence intervals for CIMP (27.7% and non-CIMP (72.3% tumors were calculated according to BMI, BMI at age 20, BMI change, trouser/skirt size, height, and physical activity. RESULTS: BMI modeled per 5 kg/m(2 increase was associated with both CIMP and non-CIMP tumors, however, HRs were attenuated when additionally adjusted for trouser/skirt size. Trouser/skirt size, per 2 size increase, was associated with both tumor subtypes, even after adjustment for BMI (CIMP HR: 1.20, 95%CI: 1.01-1.43; non-CIMP HR: 1.14, 95%CI: 1.04-1.28. Height per 5 cm was associated with both tumor sub-types, but HRs were attenuated when adjusted for body weight. BMI at age 20 was positively associated with increased risk of CIMP tumors and the association was significantly less pronounced for non-CIMP tumors (P-heterogeneity = 0.01. Physical activity was inversely associated with both subtypes, but a dose-response association was observed only for non-CIMP tumors (P-trend = 0.02. CONCLUSIONS: Body size, especially central adiposity, may increase the risk of both CIMP and non-CIMP tumors. Body fat at young age may differentially influence risk. Physical activity appears to decrease the risk of CRC regardless of these molecular subtypes.

  10. Body size, physical activity and risk of colorectal cancer with or without the CpG island methylator phenotype (CIMP).

    Science.gov (United States)

    Hughes, Laura A E; Simons, Colinda C J M; van den Brandt, Piet A; Goldbohm, R Alexandra; de Goeij, Anton F; de Bruïne, Adriaan P; van Engeland, Manon; Weijenberg, Matty P

    2011-04-05

    We investigated how body size and physical activity influence the risk of the CpG island methylator phenotype (CIMP) in colorectal cancer (CRC). In the Netherlands Cohort Study (n = 120,852), risk factors were self-reported at baseline in 1986. After 7.3 years of follow-up, 603 cases and 4,631 sub-cohort members were available. CIMP status according to the Weisenberger markers was determined using methylation specific PCR on DNA from paraffin embedded tumor tissue. Hazard rate ratios (HR) and 95% confidence intervals for CIMP (27.7%) and non-CIMP (72.3%) tumors were calculated according to BMI, BMI at age 20, BMI change, trouser/skirt size, height, and physical activity. BMI modeled per 5 kg/m(2) increase was associated with both CIMP and non-CIMP tumors, however, HRs were attenuated when additionally adjusted for trouser/skirt size. Trouser/skirt size, per 2 size increase, was associated with both tumor subtypes, even after adjustment for BMI (CIMP HR: 1.20, 95%CI: 1.01-1.43; non-CIMP HR: 1.14, 95%CI: 1.04-1.28). Height per 5 cm was associated with both tumor sub-types, but HRs were attenuated when adjusted for body weight. BMI at age 20 was positively associated with increased risk of CIMP tumors and the association was significantly less pronounced for non-CIMP tumors (P-heterogeneity = 0.01). Physical activity was inversely associated with both subtypes, but a dose-response association was observed only for non-CIMP tumors (P-trend = 0.02). Body size, especially central adiposity, may increase the risk of both CIMP and non-CIMP tumors. Body fat at young age may differentially influence risk. Physical activity appears to decrease the risk of CRC regardless of these molecular subtypes.

  11. Functional Size Measurement applied to UML-based user requirements

    NARCIS (Netherlands)

    van den Berg, Klaas; Dekkers, Ton; Oudshoorn, Rogier; Dekkers, T.

    There is a growing interest in applying standardized methods for Functional Size Measurement (FSM) to Functional User Requirements (FUR) based on models in the Unified Modelling Language (UML). No consensus exists on this issue. We analyzed the demands that FSM places on FURs. We propose a

  12. Metabolic 'engines' of flight drive genome size reduction in birds.

    Science.gov (United States)

    Wright, Natalie A; Gregory, T Ryan; Witt, Christopher C

    2014-03-22

    The tendency for flying organisms to possess small genomes has been interpreted as evidence of natural selection acting on the physical size of the genome. Nonetheless, the flight-genome link and its mechanistic basis have yet to be well established by comparative studies within a volant clade. Is there a particular functional aspect of flight such as brisk metabolism, lift production or maneuverability that impinges on the physical genome? We measured genome sizes, wing dimensions and heart, flight muscle and body masses from a phylogenetically diverse set of bird species. In phylogenetically controlled analyses, we found that genome size was negatively correlated with relative flight muscle size and heart index (i.e. ratio of heart to body mass), but positively correlated with body mass and wing loading. The proportional masses of the flight muscles and heart were the most important parameters explaining variation in genome size in multivariate models. Hence, the metabolic intensity of powered flight appears to have driven genome size reduction in birds.

  13. Preoperative body size and composition, habitual diet, and post-operative complications in elective colorectal cancer patients in Norway.

    Science.gov (United States)

    Berstad, P; Haugum, B; Helgeland, M; Bukholm, I; Almendingen, K

    2013-08-01

    Both malnutrition and obesity are related to worsened post-operative outcomes after colorectal surgery. Obese cancer patients may be malnourished as a result of short-term weight loss. The present study aimed to evaluate preoperative nutritional status, body composition and dietary intake related to post-operative complications (POC) and post-operative hospital days (POHD) in elective colorectal cancer (CRC) patients. Anthropometry, body composition measured by bioelectric spectroscopy and dietary habits assessed by a validated food-frequency questionnaire were examined in 100 newly-diagnosed CRC patients. Data from 30-day POC and POHD were collected from medical records. Nonparametric and chi-squared tests and logistic regression were used to analyse associations between body and dietary variables and post-operative outcome. Twenty-nine patients had at least one POC. The median POHD was six. Body size and composition measures and short-term weight loss were no different between patients with and without POC, or between patients with POHD body size, body composition and short-term weight loss were not related to 30-day post-operative outcomes in CRC patients. A high content of marine n-3 PUFA in preoperative habitual diets may protect against POC after CRC surgery. © 2012 The Authors Journal of Human Nutrition and Dietetics © 2012 The British Dietetic Association Ltd.

  14. Behavioral and body size correlates of energy intake underreporting by obese and normal-weight women.

    Science.gov (United States)

    Kretsch, M J; Fong, A K; Green, M W

    1999-03-01

    To examine behavioral and body size influences on the underreporting of energy intake by obese and normal-weight women. Seven-day estimated food records were kept by subjects before they participated in a 49-day residential study. Self-reported energy intake was compared with energy intake required to maintain a stable body weight during the residential study (reference standard). Energy intake bias and its relationship to various body size and behavioral measures were examined. Twenty-two, healthy, normal-weight (mean body mass index [BMI] = 21.3) and obese (mean BMI = 34.2) women aged 22 to 42 years were studied. Analysis of variance, paired t test, simple linear regression, and Pearson correlation analyses were conducted. Mean energy intake from self-reported food records was underreported by normal-weight (-9.7%) and obese (-19.4%) women. BMI correlated inversely with the energy intake difference for normal-weight women (r = -.67, P = .02), whereas the Beck Depression Inventory correlated positively with the energy intake difference for obese women (r = .73, P behavioral traits play a role in the ability of women to accurately self-report energy intake. BMI appears to be predictive of underreporting of energy intake by normal-weight women, whereas emotional factors related to depression appear to be more determinant of underreporting for obese women. Understanding causative factors of the underreporting phenomenon will help practicing dietitians to devise appropriate and realistic diet intervention plans that clients can follow to achieve meaningful change.

  15. Evidence for soft bounds in Ubuntu package sizes and mammalian body masses.

    Science.gov (United States)

    Gherardi, Marco; Mandrà, Salvatore; Bassetti, Bruno; Cosentino Lagomarsino, Marco

    2013-12-24

    The development of a complex system depends on the self-coordinated action of a large number of agents, often determining unexpected global behavior. The case of software evolution has great practical importance: knowledge of what is to be considered atypical can guide developers in recognizing and reacting to abnormal behavior. Although the initial framework of a theory of software exists, the current theoretical achievements do not fully capture existing quantitative data or predict future trends. Here we show that two elementary laws describe the evolution of package sizes in a Linux-based operating system: first, relative changes in size follow a random walk with non-Gaussian jumps; second, each size change is bounded by a limit that is dependent on the starting size, an intriguing behavior that we call "soft bound." Our approach is based on data analysis and on a simple theoretical model, which is able to reproduce empirical details without relying on any adjustable parameter and generates definite predictions. The same analysis allows us to formulate and support the hypothesis that a similar mechanism is shaping the distribution of mammalian body sizes, via size-dependent constraints during cladogenesis. Whereas generally accepted approaches struggle to reproduce the large-mass shoulder displayed by the distribution of extant mammalian species, this is a natural consequence of the softly bounded nature of the process. Additionally, the hypothesis that this model is valid has the relevant implication that, contrary to a common assumption, mammalian masses are still evolving, albeit very slowly.

  16. Niche expansion, body size, and survival in Galápagos marine iguanas.

    Science.gov (United States)

    Wikelski, M; Wrege, Peter H

    2000-07-01

    Foraging theory predicts that dietary niche breadth should expand as resource availability decreases. However, Galápagos marine iguanas often die during algae shortages (El Niños) although land plants abound where they rest and reproduce. On Seymour Norte island, a subpopulation of iguanas exhibited unique foraging behavior: they consistently included the succulent beach plant B. maritima in their diet. We investigated the consequences of land-plant feeding for body size and survival. Batis-eaters supplemented their algae diet both before and after intertidal zone foraging, and more Batis was eaten during tides unfavorable for intertidal zone foraging (dawn and dusk). Larger, energy-constrained iguanas fed more on land than did smaller animals. Compared to intertidal zone algae, Batis was 39% lower in caloric content (1.6 vs. 2.6 kcal g -1 dry mass), 56% lower in protein (8.3 vs. 18.9% dry mass) and 57% lower in nitrogen (1.3 vs. 3.0% dry mass). In spite of its lower nutrient value, iguanas that supplemented their diet with this plant were able to attain nearly twice the body size of other iguanas on the island. Age estimates indicate that many Batis-eaters survived repeated El Niño episodes during which animals of their relative size-class experienced high mortality on other islands. The larger animals were, however, completely dependent upon this supplementary source of food to maintain condition, and all perished in the 1997-1998 El Niño when high tides inundated and killed Batis on Seymour Norte Island. We hypothesize that Batis feeding developed as a local foraging tradition, and that dietary conservatism and strong foraging site fidelity explain why the inclusion of land plants in the diet has been observed in only a single population. Ultimately, a unique algae-adapted hindgut morphology and physiology may limit a switch from marine to terrestrial diet.

  17. Body Size Changes Among National Collegiate Athletic Association New England Division III Football Players, 1956-2014: Comparison With Age-Matched Population Controls.

    Science.gov (United States)

    Elliott, Kayla R; Harmatz, Jerold S; Zhao, Yanli; Greenblatt, David J

    2016-05-01

    Collegiate football programs encourage athletes to pursue high body weights. To examine position-dependent trends over time in body size characteristics among football players in the National Collegiate Athletic Association Division III New England Small College Athletic Conference (NESCAC) from 1956 to 2014 and to compare the observed absolute and relative changes with those in age-matched male population controls. Descriptive laboratory study. Medical school affiliated with a NESCAC institution. Football team rosters from the 10-member NESCAC schools, available as public documents, were analyzed along with body size data from general population males aged 20 to 29 years from the National Health and Nutrition Examination Survey (NHANES). Body weight, height, and calculated body mass index were evaluated using analysis of variance, linear regression, and nonlinear regression to determine the distribution features of size variables and changes associated with time (year), school, and position. Among NESCAC linemen, absolute and relative changes over time in body weight and body mass index exceeded corresponding changes in the NHANES population controls. New England Small College Athletic Conference offensive linemen body weights increased by 37.5% from 1956 to 2014 (192 to 264 lb [86.4 to 118.8 kg]), compared with a 12% increase (164 to 184 lb [73.8 to 82.8 kg]) since 1961 in the NHANES population controls. Body mass index changed in parallel with body weight and exceeded 35 kg/m(2) in more than 30% of contemporary NESCAC offensive linemen. Among skill players in the NESCAC group, time-related changes in body size characteristics generally paralleled those in the NHANES controls. High body weight and body mass indices were evident in offensive linemen, even among those in Division III football programs with no athletic scholarships. These characteristics may be associated with adverse cardiovascular and metabolic outcomes. We need approaches to encourage risk

  18. The effect of body coloration and group size on social partner preferences in female fighting fish (Betta splendens).

    Science.gov (United States)

    Blakeslee, C; McRobert, S P; Brown, A C; Clotfelter, E D

    2009-02-01

    Females of the fighting fish Betta splendens have been shown to associate with other B. splendens females in a manner reminiscent of shoaling behavior. Since body coloration varies dramatically in this species, and since body coloration has been shown to affect shoalmate choice in other species of fish, we examined the influence of body coloration on association preferences in female B. splendens. In dichotomous choice tests, B. splendens females spent more time swimming near groups of females (regardless of coloration) than swimming near an empty chamber, and chose to swim near fish of similar coloration to their own when choosing between two distinctly colored groups of females. When examining the interplay between body coloration and group size, focal fish spent more time swimming near larger groups (N=5) of similarly colored fish than swimming near an individual female of similar coloration. However, focal fish showed no preference when presented with an individual female of similar coloration and a larger group of females of dissimilar coloration. These results suggest that association choices in B. splendens females are strongly affected by both body coloration and by group size.

  19. Influences of sex, ontogeny and body size on the thermal ecology of Liolaemus lutzae (Squamata, Liolaemidae) in a restinga remnant in Southeastern Brazil.

    Science.gov (United States)

    Maia-Carneiro, Thiago; Rocha, Carlos Frederico Duarte

    2013-01-01

    Variations in body temperature (Tb) of lizards can be partially explained by intrinsic factors such as sex, ontogeny and body size. Liolaemus lutzae is a lizard species restricted to restingas in the Brazilian coast in the state of Rio de Janeiro. Herein, we studied sexual dimorphism and influences of sex, ontogeny, and body size to the Tb of L. lutzae. Adult males were larger than adult females, probably due to both intersexual selection and intra-sexual selection. There was intersexual difference in lizards' Tb (males hotter than females), but Tb did not differ after factored out for the effects of body size. The mean Tb of juvenile lizards was higher than that of adults after factored out for the effect of body mass. It is possible that adults may have excluded juveniles from microhabitats with better thermal regimes. Also, this might have occurred due to requirements of juveniles to maintain high growth rates. Forage searching for prey by juveniles also exposes them to high environmental temperatures. Juveniles also may have higher Tb than co-specific adults (relative to body mass) to favor prey capture. In absolute values, adult lizards tended to use microhabitats with lower temperatures than that used by juveniles, possibly to avoid risks of overheating and death. Body temperature and snout-vent length were positively related, as well as body temperature and body mass, presumably caused by the thermal inertia of the bodies (trend of a body to resist to changes in its temperature). Intrinsic factors such as sex, ontogeny and body size can affect the thermal ecology of L. lutzae, despite coastal habitat features to which they are exposed also influences the body temperature of active lizards in restinga habitats. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Higher albedos and size distribution of large transneptunian objects

    Science.gov (United States)

    Lykawka, Patryk Sofia; Mukai, Tadashi

    2005-11-01

    Transneptunian objects (TNOs) orbit beyond Neptune and do offer important clues about the formation of our solar system. Although observations have been increasing the number of discovered TNOs and improving their orbital elements, very little is known about elementary physical properties such as sizes, albedos and compositions. Due to TNOs large distances (>40 AU) and observational limitations, reliable physical information can be obtained only from brighter objects (supposedly larger bodies). According to size and albedo measurements available, it is evident the traditionally assumed albedo p=0.04 cannot hold for all TNOs, especially those with approximately absolute magnitudes H⩽5.5. That is, the largest TNOs possess higher albedos (generally >0.04) that strongly appear to increase as a function of size. Using a compilation of published data, we derived empirical relations which can provide estimations of diameters and albedos as a function of absolute magnitude. Calculations result in more accurate size/albedo estimations for TNOs with H⩽5.5 than just assuming p=0.04. Nevertheless, considering low statistics, the value p=0.04 sounds still convenient for H>5.5 non-binary TNOs as a group. We also discuss about physical processes (e.g., collisions, intrinsic activity and the presence of tenuous atmospheres) responsible for the increase of albedo among large bodies. Currently, all big TNOs (>700 km) would be capable to sustain thin atmospheres or icy frosts composed of CH 4, CO or N 2 even for body bulk densities as low as 0.5 g cm -3. A size-dependent albedo has important consequences for the TNOs size distribution, cumulative luminosity function and total mass estimations. According to our analysis, the latter can be reduced up to 50% if higher albedos are common among large bodies. Lastly, by analyzing orbital properties of classical TNOs ( 42AUbodies. For both populations, distinct absolute magnitude distributions are maximized for an inclination threshold

  1. The evolution of body size under environmental gradients in ectotherms: why should Bergmann's rule apply to lizards?

    Directory of Open Access Journals (Sweden)

    Tregenza Tom

    2008-02-01

    Full Text Available Abstract Background The impact of environmental gradients on the evolution of life history traits is a central issue in macroecology and evolutionary biology. A number of hypotheses have been formulated to explain factors shaping patterns of variation in animal mass. One such example is Bergmann's rule, which predicts that body size will be positively correlated with latitude and elevation, and hence, with decreasing environmental temperatures. A generally accepted explanation for this phenotypic response is that as body mass increases, body surface area gets proportionally smaller, which contributes to reduced rates of heat-loss. Phylogenetic and non-phylogenetic evidence reveals that endotherms follow Bergmann's rule. In contrast, while previous non-phylogenetic studies supported this prediction in up to 75% of ectotherms, recent phylogenetic comparative analyses suggest that its validity for these organisms is controversial and less understood. Moreover, little attention has been paid to why some ectotherms conform to this rule, while others do not. Here, we investigate Bergmann's rule in the six main clades forming the Liolaemus genus, one of the largest and most environmentally diverse genera of terrestrial vertebrates. A recent study conducted on some species belonging to four of these six clades concluded that Liolaemus species follow Bergmann's rule, representing the only known phylogenetic support for this model in lizards. However, a later reassessment of this evidence, performed on one of the four analysed clades, produced contrasting conclusions. Results Our results fail to support Bergmann's rule in Liolaemus lizards. Non-phylogenetic and phylogenetic analyses showed that none of the studied clades experience increasing body size with increasing latitude and elevation. Conclusion Most physiological and behavioural processes in ectotherms depend directly upon their body temperature. In cold environments, adaptations to gain heat

  2. Diet, body size, physical activity and risk of prostate cancer: An umbrella review of the evidence.

    Science.gov (United States)

    Markozannes, Georgios; Tzoulaki, Ioanna; Karli, Dimitra; Evangelou, Evangelos; Ntzani, Evangelia; Gunter, Marc J; Norat, Teresa; Ioannidis, John P; Tsilidis, Konstantinos K

    2016-12-01

    The existing literature on the relationship between diet, body size, physical activity and prostate cancer risk was summarised by the World Cancer Research Fund Continuous Update Project (CUP). An evaluation of the robustness of this evidence is required to help inform public health policy. The robustness of this evidence was evaluated using several criteria addressing evidence strength and validity, including the statistical significance of the random effects summary estimate and of the largest study in a meta-analysis, number of prostate cancer cases, between-study heterogeneity, 95% prediction intervals, small-study effects bias, excess significance bias and sensitivity analyses with credibility ceilings. A total of 248 meta-analyses were extracted from the CUP, which studied associations of 23 foods, 31 nutrients, eight indices of body size and three indices of physical activity with risk of total prostate cancer development, mortality or cancer development by stage and grade. Of the 176 meta-analyses using a continuous scale to measure the exposures, no association presented strong evidence by satisfying all the aforementioned criteria. Only the association of height with total prostate cancer incidence and mortality presented highly suggestive evidence with a 4% higher risk per 5 cm greater height (95% confidence interval, 1.03, 1.05). Associations for body mass index, weight, height, dietary calcium and spirits intake were supported by suggestive evidence. Overall, the association of diet, body size, physical activity and prostate cancer has been extensively studied, but no association was graded with strong evidence. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Monte Carlo simulation of a stand-up type whole body counter using different sized BOMAB phantoms

    International Nuclear Information System (INIS)

    Park, Minjung; Yoo, Jaeryong; Park, Seyoung; Ha, Wiho; Lee, Seungsook; Park, Minjung; Yoo, Jaeryong; Kim, Kwangpyo

    2013-01-01

    It is necessary to assess internal contamination level to determine the need for medical intervention. Whole Body Counter (WBC) is used to measure incorporated radioactive materials inside the human body. Also, WBC is standard in vivo method and used for preparedness of response to radiological emergencies. To operate this equipment correctly, proper energy and efficiency calibrations must be performed. WBC is usually calibrated using a Bottle Manikin ABsorber (BOMAB) Phantom, which is the industrial standard. The problem occurs when the subjects to be measured have different physical characteristics (height or weight) from a phantom used in calibration. In radiation emergency situations, this problem is expected to worsen because there are special populations whose physical characteristics are different from reference male, for example children and women. The aim of this study is to resolve this problem by simulating counting efficiency of different sized BOMAB phantoms using Monte Carlo techniques. The counting efficiency response of the WBC has been modeled for different sized four BOMAB phantoms using MCNPX. The stand-up type WBC has different efficiency response on phantom size since this WBC has different geometry from other scanning-type or non-linear geometry WBC. In emergency monitoring situations, it is important to estimate activity of various sized persons. Therefore, it is necessary to apply appropriate counting efficiency according to person size. Further investigations are needed to optimize methodology for measuring small object in the stand-up type WBC

  4. Molecular Characterization of Bovine SMO Gene and Effects of Its Genetic Variations on Body Size Traits in Qinchuan Cattle (Bos taurus)

    Science.gov (United States)

    Zhang, Ya-Ran; Gui, Lin-Sheng; Li, Yao-Kun; Jiang, Bi-Jie; Wang, Hong-Cheng; Zhang, Ying-Ying; Zan, Lin-Sen

    2015-01-01

    Smoothened (Smo)-mediated Hedgehog (Hh) signaling pathway governs the patterning, morphogenesis and growth of many different regions within animal body plans. This study evaluated the effects of genetic variations of the bovine SMO gene on economically important body size traits in Chinese Qinchuan cattle. Altogether, eight single nucleotide polymorphisms (SNPs: 1–8) were identified and genotyped via direct sequencing covering most of the coding region and 3ʹUTR of the bovine SMO gene. Both the p.698Ser.>Ser. synonymous mutation resulted from SNP1 and the p.700Ser.>Pro. non-synonymous mutation caused by SNP2 mapped to the intracellular C-terminal tail of bovine Smo protein; the other six SNPs were non-coding variants located in the 3ʹUTR. The linkage disequilibrium was analyzed, and five haplotypes were discovered in 520 Qinchuan cattle. Association analyses showed that SNP2, SNP3/5, SNP4 and SNP6/7 were significantly associated with some body size traits (p 0.05). Meanwhile, cattle with wild-type combined haplotype Hap1/Hap1 had significantly (p < 0.05) greater body length than those with Hap2/Hap2. Our results indicate that variations in the SMO gene could affect body size traits of Qinchuan cattle, and the wild-type haplotype Hap1 together with the wild-type alleles of these detected SNPs in the SMO gene could be used to breed cattle with superior body size traits. Therefore, our results could be helpful for marker-assisted selection in beef cattle breeding programs. PMID:26225956

  5. Many-body theory and Energy Density Functionals

    Energy Technology Data Exchange (ETDEWEB)

    Baldo, M. [INFN, Catania (Italy)

    2016-07-15

    In this paper a method is first presented to construct an Energy Density Functional on a microscopic basis. The approach is based on the Kohn-Sham method, where one introduces explicitly the Nuclear Matter Equation of State, which can be obtained by an accurate many-body calculation. In this way it connects the functional to the bare nucleon-nucleon interaction. It is shown that the resulting functional can be performing as the best Gogny force functional. In the second part of the paper it is shown how one can go beyond the mean-field level and the difficulty that can appear. The method is based on the particle-vibration coupling scheme and a formalism is presented that can handle the correct use of the vibrational degrees of freedom within a microscopic approach. (orig.)

  6. Physical function and muscle strength in sporadic inclusion body myositis

    DEFF Research Database (Denmark)

    Jørgensen, Anders N; Aagaard, Per; Nielsen, Jakob L

    2017-01-01

    INTRODUCTION: In this study, self-reported physical function, functional capacity, and isolated muscle function were investigated in sporadic inclusion body myositis (sIBM) patients. METHODS: The 36-item Short Form (SF-36) Health Survey and 2-min walk test (2MWT), timed up & go test (TUG), and 30-s...

  7. Three-point correlation functions of giant magnons with finite size

    International Nuclear Information System (INIS)

    Ahn, Changrim; Bozhilov, Plamen

    2011-01-01

    We compute holographic three-point correlation functions or structure constants of a zero-momentum dilaton operator and two (dyonic) giant magnon string states with a finite-size length in the semiclassical approximation. We show that the semiclassical structure constants match exactly with the three-point functions between two su(2) magnon single trace operators with finite size and the Lagrangian in the large 't Hooft coupling constant limit. A special limit J>>√(λ) of our result is compared with the relevant result based on the Luescher corrections.

  8. [The relationship between adolescent body size and health promoting behavior and biochemical indicator factors].

    Science.gov (United States)

    Chen, Hsiu-Chih; Chen, Hsing-Mei; Chen, Min-Li; Chiang, Chih-Ming; Chen, Mei-Yen

    2012-06-01

    Tainan City has the third highest prevalence of junior high school student obesity of all administrative districts in Taiwan. School nurses play an important role in promoting student health. Understanding the factors that significantly impact student weight is critical to designing effective student health promotion programs. This study explored the relationships between health promotion behavior and serum biomarker variables and body size. Researchers used a cross-sectional descriptive study design and stratified cluster random sampling. Subjects were 7th graders who received an in-school health checkup with blood test at 41 public junior high schools in Tainan City between July 2010 and May 2011. Research instruments included the adolescent health promotion (AHP) scale, serum biochemical profile and BMI (body mass index). Obtained data were analyzed using descriptive and inferential statistics. Of the 726 students who participated in this study, 22.2% were underweight and 23.8% were overweight or obese. Higher AHP scores correlated with better biomarkers and body size. Multivariate analysis found factors that increased the risk of being overweight included: being male, having a father with a relatively low level of education, playing video games frequently, and doing little or no exercise (odds ratio = 1.93, 1.75, 1.07, 1.04, respectively). Participants with relatively healthy behaviors had better biomarkers and a lower risk of being overweight. Findings can support the development of evidence-based school programs to promote student health.

  9. The influence of age and sex on genetic associations with adult body size and shape: a large-scale genome-wide interaction study

    OpenAIRE

    Winkler, Thomas W.; Heid, Iris M.; Gorski, Mathias

    2015-01-01

    Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially between men and women. To systematically screen for age-and/or sex-specific effects of genetic variants on BMI and WHRadjBMI, we performed meta-analyses of 114 studies (up to 320,485 individuals of Eur...

  10. The externally corrected coupled cluster approach with four- and five-body clusters from the CASSCF wave function.

    Science.gov (United States)

    Xu, Enhua; Li, Shuhua

    2015-03-07

    An externally corrected CCSDt (coupled cluster with singles, doubles, and active triples) approach employing four- and five-body clusters from the complete active space self-consistent field (CASSCF) wave function (denoted as ecCCSDt-CASSCF) is presented. The quadruple and quintuple excitation amplitudes within the active space are extracted from the CASSCF wave function and then fed into the CCSDt-like equations, which can be solved in an iterative way as the standard CCSDt equations. With a size-extensive CASSCF reference function, the ecCCSDt-CASSCF method is size-extensive. When the CASSCF wave function is readily available, the computational cost of the ecCCSDt-CASSCF method scales as the popular CCSD method (if the number of active orbitals is small compared to the total number of orbitals). The ecCCSDt-CASSCF approach has been applied to investigate the potential energy surface for the simultaneous dissociation of two O-H bonds in H2O, the equilibrium distances and spectroscopic constants of 4 diatomic molecules (F2(+), O2(+), Be2, and NiC), and the reaction barriers for the automerization reaction of cyclobutadiene and the Cl + O3 → ClO + O2 reaction. In most cases, the ecCCSDt-CASSCF approach can provide better results than the CASPT2 (second order perturbation theory with a CASSCF reference function) and CCSDT methods.

  11. Functional-dependent and size-dependent uptake of nanoparticles in PC12

    International Nuclear Information System (INIS)

    Sakai, N; Matsui, Y; Nakayama, A; Yoneda, M; Tsuda, A

    2011-01-01

    It is suggested that the uptake of nanoparticles is changed by the particle size or the surface modification. In this study, we quantified the uptake of nanoparticles in PC12 cells exposed Quantum Dots with different surface modification or fluorescent polystyrene particles with different particle size. The PC12 cells were exposed three types of the Quantum Dots (carboxyl base-functionalized, amino base-functionalized or non-base-functionalized) or three types of the fluorescent particles (22 nm, 100 nm or 1000 nm) for 3 hours. The uptake of the nanoparticles was quantified with a spectrofluorophotometer. The carboxyl base-functionalized Quantum Dots were considerably taken up by the cells than the non-base-functionalized Quantum Dots. Conversely, the amino base-functionalized Quantum Dots were taken up by the cells less frequently than the non-base-functionalized Quantum Dots. The particle number of the 22 nm-nanoparticles taken up by the cells was about 53 times higher than the 100 nm-particles. However, the particle weight of the 100 nm-particles taken up by the cells was higher than that of the 22 nm-nanoparticles. The 1000 nm-particles were adhered to the cell membrane, but they were little taken up by the cells. We concluded that nanoparticles can be taken up nerve cells in functional-dependent and size-dependent manners.

  12. Polydisperse-particle-size-distribution function determined from intensity profile of angularly scattered light

    International Nuclear Information System (INIS)

    Alger, T.W.

    1979-01-01

    A new method for determining the particle-size-distribution function of a polydispersion of spherical particles is presented. The inversion technique for the particle-size-distribution function is based upon matching the measured intensity profile of angularly scattered light with a summation of the intensity contributions of a series of appropriately spaced, narrowband, size-distribution functions. A numerical optimization technique is used to determine the strengths of the individual bands that yield the best agreement with the measured scattered-light-intensity profile. Because Mie theory is used, the method is applicable to spherical particles of all sizes. Several numerical examples demonstrate the application of this inversion method

  13. Linking mean body size of pelagic Cladocera to environmental variables in Precambrian Shield lakes: A paleolimnological approach

    Directory of Open Access Journals (Sweden)

    John P. SMOL

    2008-02-01

    Full Text Available Daphnia and Bosmina fragments were identified and measured in the surface sediments of 42 lakes in the Muskoka-Haliburton region of Ontario, Canada, in an attempt to identify environmental factors that may influence cladoceran body size. Specifically, pecten length on Daphnia post-abdominal claws, antennule length on Bosmina headshields, and carapace and mucro lengths of Bosmina carapaces were measured. These measurements were then compared to limnological variables previously identified as possibly influencing cladoceran size, including dissolved organic carbon (DOC, total phosphorus (TP, pH, calcium (Ca, Chaoborus density, and fish presence/absence. Cladoceran size displayed a linear relationship to TP, with larger Bosmina and Daphnia present in lakes with lower nutrient levels. We suspect that, as larger individuals are more efficient grazers, they may competitively exclude smaller individuals when nutrients are limiting in these lakes. Bosmina mucro length and cladoceran community size structure displayed a step response to DOC, with mean size significantly smaller when DOC concentrations were higher than 5.89 mg L-1. Daphnia pecten length displayed a negative linear relationship to DOC above a concentration of 4.90 mg l-1. Reduced predation pressure from gape-limited macroinvertebrate predators, such as Chaoborus, may have influenced these relationships. DOC was also highly correlated to TP in these lakes, and size trends might be responding to the TP gradient rather than the DOC gradient. Mean cladoceran body size in acidic lakes (pH 6.0. There was no relationship between size structure and Ca concentrations, attributed to a narrow Ca gradient in these lakes. Predation effects were examined using limited Chaoborus density and fish presence/absence data. Although there were no significant relationships between cladoceran size and Chaoborus density, some significant relationships between size variables and fish predation were identified. The

  14. Cues to body size in the formant spacing of male koala (Phascolarctos cinereus) bellows: honesty in an exaggerated trait.

    Science.gov (United States)

    Charlton, Benjamin D; Ellis, William A H; McKinnon, Allan J; Cowin, Gary J; Brumm, Jacqui; Nilsson, Karen; Fitch, W Tecumseh

    2011-10-15

    Determining the information content of vocal signals and understanding morphological modifications of vocal anatomy are key steps towards revealing the selection pressures acting on a given species' vocal communication system. Here, we used a combination of acoustic and anatomical data to investigate whether male koala bellows provide reliable information on the caller's body size, and to confirm whether male koalas have a permanently descended larynx. Our results indicate that the spectral prominences of male koala bellows are formants (vocal tract resonances), and show that larger males have lower formant spacing. In contrast, no relationship between body size and the fundamental frequency was found. Anatomical investigations revealed that male koalas have a permanently descended larynx: the first example of this in a marsupial. Furthermore, we found a deeply anchored sternothyroid muscle that could allow male koalas to retract their larynx into the thorax. While this would explain the low formant spacing of the exhalation and initial inhalation phases of male bellows, further research will be required to reveal the anatomical basis for the formant spacing of the later inhalation phases, which is predictive of vocal tract lengths of around 50 cm (nearly the length of an adult koala's body). Taken together, these findings show that the formant spacing of male koala bellows has the potential to provide receivers with reliable information on the caller's body size, and reveal that vocal adaptations allowing callers to exaggerate (or maximise) the acoustic impression of their size have evolved independently in marsupials and placental mammals.

  15. Two-body correlation functions in dilute nuclear matter

    International Nuclear Information System (INIS)

    Isayev, A A

    2006-01-01

    Finding the distinct features of the crossover from the regime of large overlapping Cooper pairs to the limit of non-overlapping pairs of fermions (Shafroth pairs) in multicomponent Fermi systems remains one of the actual problems in a quantum many-body theory. Here this transition is studied by calculating the two-body density, spin and isospin correlation functions in dilute asymmetric nuclear matter. It is shown that criterion of the crossover (Phys. Rev. Lett. 95, 090402 (2005)), consisting in the change of the sign of the density correlation function at low momentum transfer, fails to describe correctly the density-driven BEC-BCS transition at finite isospin asymmetry or finite temperature. As an unambiguous signature of the BEC-BCS transition, there can be used the presence (BCS regime) or absence (BEC regime) of the singularity in the momentum distribution of the quasiparticle density of states

  16. Body Size Changes Among National Collegiate Athletic Association New England Division III Football Players, 1956−2014: Comparison With Age-Matched Population Controls

    Science.gov (United States)

    Elliott, Kayla R.; Harmatz, Jerold S.; Zhao, Yanli; Greenblatt, David J.

    2016-01-01

    Context:  Collegiate football programs encourage athletes to pursue high body weights. Objective:  To examine position-dependent trends over time in body size characteristics among football players in the National Collegiate Athletic Association Division III New England Small College Athletic Conference (NESCAC) from 1956 to 2014 and to compare the observed absolute and relative changes with those in age-matched male population controls. Design:  Descriptive laboratory study. Setting:  Medical school affiliated with a NESCAC institution. Patients or Other Participants:  Football team rosters from the 10-member NESCAC schools, available as public documents, were analyzed along with body size data from general population males aged 20 to 29 years from the National Health and Nutrition Examination Survey (NHANES). Main Outcome Measure(s):  Body weight, height, and calculated body mass index were evaluated using analysis of variance, linear regression, and nonlinear regression to determine the distribution features of size variables and changes associated with time (year), school, and position. Results:  Among NESCAC linemen, absolute and relative changes over time in body weight and body mass index exceeded corresponding changes in the NHANES population controls. New England Small College Athletic Conference offensive linemen body weights increased by 37.5% from 1956 to 2014 (192 to 264 lb [86.4 to 118.8 kg]), compared with a 12% increase (164 to 184 lb [73.8 to 82.8 kg]) since 1961 in the NHANES population controls. Body mass index changed in parallel with body weight and exceeded 35 kg/m2 in more than 30% of contemporary NESCAC offensive linemen. Among skill players in the NESCAC group, time-related changes in body size characteristics generally paralleled those in the NHANES controls. Conclusions:  High body weight and body mass indices were evident in offensive linemen, even among those in Division III football programs with no athletic

  17. Ovarian cancer and body size

    DEFF Research Database (Denmark)

    Mosgaard, Berit Jul

    2012-01-01

    Only about half the studies that have collected information on the relevance of women's height and body mass index to their risk of developing ovarian cancer have published their results, and findings are inconsistent. Here, we bring together the worldwide evidence, published and unpublished...

  18. Influence of body size on Cu bioaccumulation in zebra mussels Dreissena polymorpha exposed to different sources of particle-associated Cu.

    Science.gov (United States)

    Zhong, Huan; Kraemer, Lisa; Evans, Douglas

    2013-10-15

    Size of organisms is critical in controlling metal bioavailability and bioaccumulation, while mechanisms of size-related metal bioaccumulation are not fully understood. To investigate the influences of different sources of particle-associated Cu on body size-related Cu bioavailability and bioaccumulation, zebra mussels (Dreissena polymorpha) of different sizes were exposed to stable Cu isotope ((65)Cu) spiked algae (Chlorella vulgaris) or sediments in the laboratory and the Cu tissue concentration-size relationships were compared with that in unexposed mussels. Copper tissue concentrations decreased with mussel size (tissue or shell dry weight) in both unexposed and algal-exposed mussels with similar decreasing patterns, but were independent of size in sediment-exposed mussels. Furthermore, the relative contribution of Cu uptake from algae (65-91%) to Cu bioaccumulation is always higher than that from sediments (9-35%), possibly due to the higher bioavailability of algal-Cu. Therefore, the size-related ingestion of algae could be more important in influencing the size-related variations in Cu bioaccumulation. However, the relative contribution of sediment-Cu to Cu bioaccumulation increased with body size and thus sediment ingestion may also affect the size-related Cu variations in larger mussels (tissue weight >7.5mg). This study highlights the importance of considering exposure pathways in normalization of metal concentration variation when using bivalves as biomonitors. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. A functionally relevant tool for the body following spinal cord injury.

    Directory of Open Access Journals (Sweden)

    Mariella Pazzaglia

    Full Text Available A tool such as a prosthetic device that extends or restores movement may become part of the identity of the person to whom it belongs. For example, some individuals with spinal cord injury (SCI adapt their body and action representation to incorporate their wheelchairs. However, it remains unclear whether the bodily assimilation of a relevant external tool develops as a consequence of altered sensory and motor inputs from the body or of prolonged confinement sitting or lying in the wheelchair. To explore such relationships, we used a principal component analysis (PCA on collected structured reports detailing introspective experiences of wheelchair use in 55 wheelchair-bound individuals with SCI. Among all patients, the regular use of a wheelchair induced the perception that the body's edges are not fixed, but are instead plastic and flexible to include the wheelchair. The PCA revealed the presence of three major components. In particular, the functional aspect of the sense of embodiment concerning the wheelchair appeared to be modulated by disconnected body segments. Neither an effect of time since injury nor an effect of exposure to/experience of was detected. Patients with lesions in the lower spinal cord and with loss of movement and sensation in the legs but who retained upper body movement showed a higher degree of functional embodiment than those with lesions in the upper spinal cord and impairment in the entire body. In essence, the tool did not become an extension of the immobile limbs; rather, it became an actual tangible substitution of the functionality of the affected body part. These findings suggest that the brain can incorporate relevant artificial tools into the body schema via the natural process of continuously updating bodily signals. The ability to embody new essential objects extends the potentiality of physically impaired persons and can be used for their rehabilitation.

  20. Body iron is associated with cognitive executive planning function in college women.

    Science.gov (United States)

    Blanton, Cynthia A; Green, Michael W; Kretsch, Mary J

    2013-03-14

    Evidence of the relationship between altered cognitive function and depleted Fe status is accumulating in women of reproductive age but the degree of Fe deficiency associated with negative neuropsychological outcomes needs to be delineated. Data are limited regarding this relationship in university women in whom optimal cognitive function is critical to academic success. The aim of the present study was to examine the relationship between body Fe, in the absence of Fe-deficiency anaemia, and neuropsychological function in young college women. Healthy, non-anaemic undergraduate women (n 42) provided a blood sample and completed a standardised cognitive test battery consisting of one manual (Tower of London (TOL), a measure of central executive function) and five computerised (Bakan vigilance task, mental rotation, simple reaction time, immediate word recall and two-finger tapping) tasks. Women's body Fe ranged from - 4·2 to 8·1 mg/kg. General linear model ANOVA revealed a significant effect of body Fe on TOL planning time (P= 0·002). Spearman's correlation coefficients showed a significant inverse relationship between body Fe and TOL planning time for move categories 4 (r - 0·39, P= 0·01) and 5 (r - 0·47, P= 0·002). Performance on the computerised cognitive tasks was not affected by body Fe level. These findings suggest that Fe status in the absence of anaemia is positively associated with central executive function in otherwise healthy college women.

  1. Wintering ecology of sympatric subspecies of Sandhill Crane: Correlations between body size, site fidelity, and movement patterns

    Science.gov (United States)

    Ivey, Gary L.; Dugger, Bruce D.; Herziger, Caroline P.; Casazza, Michael L.; Fleskes, Joseph P.

    2015-01-01

    Body size is known to correlate with many aspects of life history in birds, and this knowledge can be used to manage and conserve bird species. However, few studies have compared the wintering ecology of sympatric subspecies that vary significantly in body size. We used radiotelemetry to examine the relationship between body size and site fidelity, movements, and home range in 2 subspecies of Sandhill Crane (Grus canadensis) wintering in the Sacramento–San Joaquin Delta of California, USA. Both subspecies showed high interannual return rates to the Delta study area, but Greater Sandhill Cranes (G. c. tabida) showed stronger within-winter fidelity to landscapes in our study region and to roost complexes within landscapes than did Lesser Sandhill Cranes (G. c. canadensis). Foraging flights from roost sites were shorter for G. c. tabida than for G. c. canadensis (1.9 ± 0.01 km vs. 4.5 ± 0.01 km, respectively) and, consequently, the mean size of 95% fixed-kernel winter home ranges was an order of magnitude smaller for G. c. tabida than for G. c. canadensis (1.9 ± 0.4 km2 vs. 21.9 ± 1.9 km2, respectively). Strong site fidelity indicates that conservation planning to manage for adequate food resources around traditional roost sites can be effective for meeting the habitat needs of these cranes, but the scale of conservation efforts should differ by subspecies. Analysis of movement patterns suggests that conservation planners and managers should consider all habitats within 5 km of a known G. c. tabida roost and within 10 km of a G. c. canadensis roost when planning for habitat management, mitigation, acquisition, and easements.

  2. Body Size Regression Formulae, Proximate Composition and Energy Density of Eastern Bering Sea Mesopelagic Fish and Squid.

    Science.gov (United States)

    Sinclair, Elizabeth H; Walker, William A; Thomason, James R

    2015-01-01

    The ecological significance of fish and squid of the mesopelagic zone (200 m-1000 m) is evident by their pervasiveness in the diets of a broad spectrum of upper pelagic predators including other fishes and squids, seabirds and marine mammals. As diel vertical migrators, mesopelagic micronekton are recognized as an important trophic link between the deep scattering layer and upper surface waters, yet fundamental aspects of the life history and energetic contribution to the food web for most are undescribed. Here, we present newly derived regression equations for 32 species of mesopelagic fish and squid based on the relationship between body size and the size of hard parts typically used to identify prey species in predator diet studies. We describe the proximate composition and energy density of 31 species collected in the eastern Bering Sea during May 1999 and 2000. Energy values are categorized by body size as a proxy for relative age and can be cross-referenced with the derived regression equations. Data are tabularized to facilitate direct application to predator diet studies and food web models.

  3. The effect of flexible body armour on pulmonary function.

    Science.gov (United States)

    Armstrong, Nicola C; Gay, Louise A

    2016-05-01

    The additional mass and fit of current military in-service body armour (ISBA) can reduce pulmonary function in a way that is characteristic of a restrictive respiratory impairment. This could ultimately impair exercise capacity and military performance. This study compared pulmonary function (forced vital capacity [FVC] and forced expiratory volume in 1 s [FEV1]) in UK ISBA (15.3 kg) and three flexible body armours (BAs) (FA1: 10 kg; FA2: 7.8 kg; FA3: 10 kg) in eight male soldiers. The design of the ballistic plates differed between the BAs to improve the flexibility. FVC and FEV1 were reduced by 4-6%, without reduction in FEV1/FVC for ISBA, FA2 and FA3, when compared to NoBA (p armour caused a mild restrictive ventilatory impairment. However, the design of the armour can be modified to reduce the degree of this impairment. This may lead to improvements in soldier performance during tasks that require body armour.

  4. Heterogeneous effects of market integration on subadult body size and nutritional status among the Shuar of Amazonian Ecuador

    Science.gov (United States)

    Urlacher, Samuel S.; Liebert, Melissa A.; Snodgrass, J. Josh; Blackwell, Aaron D.; Cepon-Robins, Tara J.; Gildner, Theresa E.; Madimenos, Felicia C.; Amir, Dorsa; Bribiescas, Richard G.; Sugiyama, Lawrence S.

    2016-01-01

    Background Market integration (MI) – increasing production for and consumption from a market-based economy – is drastically altering traditional ways of life and environmental conditions among indigenous Amazonian peoples. The effects of MI on the biology and health of Amazonian children and adolescents, however, remain unclear. Aim This study examines the impact of MI on subadult body size and nutritional status at the population, regional, and household levels among the Shuar of Amazonian Ecuador. Subjects and Methods Anthropometric data were collected between 2005 and 2014 from 2,164 Shuar (age 2-19 years) living in two geographic regions differing in general degree of MI. High-resolution household economic, lifestyle, and dietary data were collected from a subsample of 631 participants. Analyses were performed to investigate relationships between body size and year of data collection, region, and specific aspects of household MI. Results Results from temporal and regional analyses suggest that MI has a significant and overall positive impact on Shuar body size and nutritional status. However, household-level results exhibit nuanced and heterogeneous specific effects of MI underlying these overarching relationships. Conclusion This study provides novel insight into the complex socio-ecological pathways linking MI, physical growth, and health among the Shuar and other indigenous Amazonian populations. PMID:27230632

  5. Monte Carlo simulation of calibration of shadow shield scanning bed whole body monitor using different size BOMAB phantoms

    International Nuclear Information System (INIS)

    Bhati, S.; Patni, H.K.; Singh, I.S.; Garg, S.P.

    2005-01-01

    A shadow shield scanning bed whole body monitor incorporating a (102 mm dia x 76 mm thick) NaI(Tl) detector, is employed for assessment of high-energy photon emitters at BARC. The monitor is calibrated using a Reference BOMAB phantom representative of an average Indian radiation worker. However to account for the size variation in the physique of workers, it is required to calibrate the system with different size BOMAB phantoms which is both difficult and expensive. Therefore, a theoretical approach based on Monte Carlo techniques has been employed to calibrate the system with BOMAB phantoms of different sizes for several radionuclides of interest. A computer program developed for this purpose, simulates the scanning geometry of the whole body monitor and computes detection efficiencies for the BARC Reference phantom (63 kg/168 cm), ICRP Reference phantom (70 kg/170 cm) and several of its scaled versions covering a wide range of body builds. The detection efficiencies computed for different photon energies for BARC Reference phantom were found to be in very good agreement with experimental data, thus validating the Monte Carlo scheme used in the computer code. The results from this study could be used for assessment of internal contamination due to high-energy photon emitters for radiation workers of different physiques. (author)

  6. Metabolic expenditures of lunge feeding rorquals across scale: implications for the evolution of filter feeding and the limits to maximum body size.

    Directory of Open Access Journals (Sweden)

    Jean Potvin

    Full Text Available Bulk-filter feeding is an energetically efficient strategy for resource acquisition and assimilation, and facilitates the maintenance of extreme body size as exemplified by baleen whales (Mysticeti and multiple lineages of bony and cartilaginous fishes. Among mysticetes, rorqual whales (Balaenopteridae exhibit an intermittent ram filter feeding mode, lunge feeding, which requires the abandonment of body-streamlining in favor of a high-drag, mouth-open configuration aimed at engulfing a very large amount of prey-laden water. Particularly while lunge feeding on krill (the most widespread prey preference among rorquals, the effort required during engulfment involve short bouts of high-intensity muscle activity that demand high metabolic output. We used computational modeling together with morphological and kinematic data on humpback (Megaptera noveaangliae, fin (Balaenoptera physalus, blue (Balaenoptera musculus and minke (Balaenoptera acutorostrata whales to estimate engulfment power output in comparison with standard metrics of metabolic rate. The simulations reveal that engulfment metabolism increases across the full body size of the larger rorqual species to nearly 50 times the basal metabolic rate of terrestrial mammals of the same body mass. Moreover, they suggest that the metabolism of the largest body sizes runs with significant oxygen deficits during mouth opening, namely, 20% over maximum VO2 at the size of the largest blue whales, thus requiring significant contributions from anaerobic catabolism during a lunge and significant recovery after a lunge. Our analyses show that engulfment metabolism is also significantly lower for smaller adults, typically one-tenth to one-half VO2|max. These results not only point to a physiological limit on maximum body size in this lineage, but also have major implications for the ontogeny of extant rorquals as well as the evolutionary pathways used by ancestral toothed whales to transition from hunting

  7. Influence of size-corrected bound-electron contribution on nanometric silver dielectric function. Sizing through optical extinction spectroscopy

    International Nuclear Information System (INIS)

    Santillán, J M J; Videla, F A; Scaffardi, L B; Schinca, D C; Fernández van Raap, M B; Muraca, D

    2013-01-01

    The study of metal nanoparticles (NPs) is of great interest due to their ability to enhance optical fields on the nanometric scale, which makes them interesting for various applications in several fields of science and technology. In particular, their optical properties depend on the dielectric function of the metal, its size, shape and surrounding environment. This work analyses the contributions of free and bound electrons to the complex dielectric function of spherical silver NPs and their influence on the optical extinction spectra. The contribution of free electrons is usually corrected for particle size under 10 nm, introducing a modification of the damping constant to account for the extra collisions with the particle's boundary. For the contribution of bound electrons, we considered the interband transitions from the d-band to the conduction band including the size dependence of the electronic density states for radii below 2 nm. Bearing in mind these specific modifications, it was possible to determine optical and band energy parameters by fitting the bulk complex dielectric function. The results obtained from the optimum fit are: K bulk = 2 × 10 24 (coefficient for bound-electron contribution), E g = 1.91 eV (gap energy), E F = 4.12 eV (Fermi energy), and γ b = 1.5 × 10 14 Hz (damping constant for bound electrons). Based on this size-dependent dielectric function, extinction spectra of silver particles in the nanometric–subnanometric radius range can be calculated using Mie's theory, and its size behaviour analysed. These studies are applied to fit experimental extinction spectrum of very small spherical particles fabricated by fs laser ablation of a solid target in water. From the fitting, the structure and size distribution of core radius and shell thickness of the colloidal suspension could be determined. The spectroscopic results suggest that the colloidal suspension is composed by two types of structures: bare core and core–shell. The former

  8. Rictor/TORC2 regulates Caenorhabditis elegans fat storage, body size, and development through sgk-1.

    Directory of Open Access Journals (Sweden)

    Kevin T Jones

    2009-03-01

    Full Text Available The target of rapamycin (TOR kinase coordinately regulates fundamental metabolic and cellular processes to support growth, proliferation, survival, and differentiation, and consequently it has been proposed as a therapeutic target for the treatment of cancer, metabolic disease, and aging. The TOR kinase is found in two biochemically and functionally distinct complexes, termed TORC1 and TORC2. Aided by the compound rapamycin, which specifically inhibits TORC1, the role of TORC1 in regulating translation and cellular growth has been extensively studied. The physiological roles of TORC2 have remained largely elusive due to the lack of pharmacological inhibitors and its genetic lethality in mammals. Among potential targets of TORC2, the pro-survival kinase AKT has garnered much attention. Within the context of intact animals, however, the physiological consequences of phosphorylation of AKT by TORC2 remain poorly understood. Here we describe viable loss-of-function mutants in the Caenorhabditis elegans homolog of the TORC2-specific component, Rictor (CeRictor. These mutants display a mild developmental delay and decreased body size, but have increased lipid storage. These functions of CeRictor are not mediated through the regulation of AKT kinases or their major downstream target, the insulin-regulated FOXO transcription factor DAF-16. We found that loss of sgk-1, a homolog of the serum- and glucocorticoid-induced kinase, mimics the developmental, growth, and metabolic phenotypes of CeRictor mutants, while a novel, gain-of-function mutation in sgk-1 suppresses these phenotypes, indicating that SGK-1 is a mediator of CeRictor activity. These findings identify new physiological roles for TORC2, mediated by SGK, in regulation of C. elegans lipid accumulation and growth, and they challenge the notion that AKT is the primary effector of TORC2 function.

  9. Estimation of Body Weight from Body Size Measurements and Body Condition Scores in Dairy Cows

    DEFF Research Database (Denmark)

    Enevoldsen, Carsten; Kristensen, T.

    1997-01-01

    , and body condition score were consistently associated with BW. The coefficients of multiple determination varied from 80 to 89%. The number of significant terms and the parameter estimates of the models differed markedly among groups of cows. Apparently, these differences were due to breed and feeding...... regimen. Results from this study indicate that a reliable model for estimating BW of very different dairy cows maintained in a wide range of environments can be developed using body condition score, demographic information, and measurements of hip height and hip width. However, for management purposes......The objective of this study was to evaluate the use of hip height and width, body condition score, and relevant demographic information to predict body weight (BW) of dairy cows. Seven regression models were developed from data from 972 observations of 554 cows. Parity, hip height, hip width...

  10. Correlation functions for Hermitian many-body systems: Necessary conditions

    International Nuclear Information System (INIS)

    Brown, E.B.

    1994-01-01

    Lee [Phys. Rev. B 47, 8293 (1993)] has shown that the odd-numbered derivatives of the Kubo autocorrelation function vanish at t=0. We show that this condition is based on a more general property of nondiagonal Kubo correlation functions. This general property provides that certain functional forms (e.g., simple exponential decay) are not admissible for any symmetric or antisymmetric Kubo correlation function in a Hermitian many-body system. Lee's result emerges as a special case of this result. Applications to translationally invariant systems and systems with rotational symmetries are also demonstrated

  11. The role of electrostatic charging of small and intermediate sized bodies in the solar system

    International Nuclear Information System (INIS)

    Mendis, D.A.

    1981-01-01

    The role of electrostatic charging of small and intermediate sized bodies in the solar system is reviewed. These bodies include planetary, interplanetary and cometary dust as well as cometary nuclei (at large heliocentric distances), asteroids and the larger bodies in the Saturnian ring system. While this charging has both physical and dynamical consequences for the small dust grains, it has only physical consequences for the larger bodies. The main physical consequences for the small grains are electrostatic erosion (''chipping'') and disruption, whereas for the larger bodies they include electrostatic levitation and blow-off of fine loose dust from their surfaces. A large variety of solar system phenomena, recently observed by the Pioneer and Voyager deep space probes as well as the HEOS-2 earth satellite, are explained in terms of these processes. Certain peculiar features observed in the dust tails of comets as well as the spatial orientation of the zodiacal dust cloud may also be explained along these lines. The possible electrostatic erosion of the dust mantles of new comets as well as the electrostatic 'polishing' of the smaller asteroids are also discussed. (Auth.)

  12. [Influences of ration level and initial body weight on growth and size hierarchy of hybrid tilapia, Oreochromis mossambicus x O. niloticus].

    Science.gov (United States)

    Wang, Yan

    2003-02-01

    72 hybrid tilapia were distributed into twelve tanks, each stocked in six fish (A, B, C, D, E, F) with different body size. The initial body weight was 62.69 +/- 1.46 g for fish A, 56.48 +/- 1.30 g for B, 50.75 +/- 1.19 g for C, 35.56 +/- 1.18 g for D, 31.05 +/- 0.88 g for E, and 27.35 +/- 0.95 g for F (mean +/- SE). The fish were reared under four ration levels (deprived of feed, fed at 1.5% body weight per day (BW.d-1), fed at 3.0% BW.d-1, or fed excess) throughout four weeks, respectively. The specific growth rate (SGR) and feed efficiency (FE) of the fish increased with increasing ration level up to 3.0% BW.d-1, and then, SGR maintained at a constant level while FE dropped with continuing increase of ration. The variance coefficient of SGR and final body weight was relatively high in the fish that fed at 1.5% BW.d-1. For fish A, SGR was not significantly different, between 1.5% BW.d-1, 3.0% BW.d-1 and fed excess, while in fish F, relatively high variations were found among different ration treatments. This experiment revealed that the growth and size hierarchy of hybrid tilapia were related to their ration level and initial body size. Under ration levels more than 3.0% BW.d-1, SGR was usually high, and size hierarchy was relatively weak.

  13. Heterogeneous effects of market integration on sub-adult body size and nutritional status among the Shuar of Amazonian Ecuador.

    Science.gov (United States)

    Urlacher, Samuel S; Liebert, Melissa A; Josh Snodgrass, J; Blackwell, Aaron D; Cepon-Robins, Tara J; Gildner, Theresa E; Madimenos, Felicia C; Amir, Dorsa; Bribiescas, Richard G; Sugiyama, Lawrence S

    2016-07-01

    Market integration (MI)-increasing production for and consumption from a market-based economy-is drastically altering traditional ways of life and environmental conditions among indigenous Amazonian peoples. The effects of MI on the biology and health of Amazonian children and adolescents, however, remain unclear. This study examines the impact of MI on sub-adult body size and nutritional status at the population, regional and household levels among the Shuar of Amazonian Ecuador. Anthropometric data were collected between 2005-2014 from 2164 Shuar (aged 2-19 years) living in two geographic regions differing in general degree of MI. High-resolution household economic, lifestyle and dietary data were collected from a sub-sample of 631 participants. Analyses were performed to investigate relationships between body size and year of data collection, region and specific aspects of household MI. Results from temporal and regional analyses suggest that MI has a significant and overall positive impact on Shuar body size and nutritional status. However, household-level results exhibit nuanced and heterogeneous specific effects of MI underlying these overarching relationships. This study provides novel insight into the complex socio-ecological pathways linking MI, physical growth and health among the Shuar and other indigenous Amazonian populations.

  14. Body size and geographic range do not explain long term variation in fish populations: a Bayesian phylogenetic approach to testing assembly processes in stream fish assemblages.

    Directory of Open Access Journals (Sweden)

    Stephen J Jacquemin

    Full Text Available We combine evolutionary biology and community ecology to test whether two species traits, body size and geographic range, explain long term variation in local scale freshwater stream fish assemblages. Body size and geographic range are expected to influence several aspects of fish ecology, via relationships with niche breadth, dispersal, and abundance. These traits are expected to scale inversely with niche breadth or current abundance, and to scale directly with dispersal potential. However, their utility to explain long term temporal patterns in local scale abundance is not known. Comparative methods employing an existing molecular phylogeny were used to incorporate evolutionary relatedness in a test for covariation of body size and geographic range with long term (1983 - 2010 local scale population variation of fishes in West Fork White River (Indiana, USA. The Bayesian model incorporating phylogenetic uncertainty and correlated predictors indicated that neither body size nor geographic range explained significant variation in population fluctuations over a 28 year period. Phylogenetic signal data indicated that body size and geographic range were less similar among taxa than expected if trait evolution followed a purely random walk. We interpret this as evidence that local scale population variation may be influenced less by species-level traits such as body size or geographic range, and instead may be influenced more strongly by a taxon's local scale habitat and biotic assemblages.

  15. Intraspecific Allometry of Basal Metabolic Rate : Relations with Body Size, Temperature, Composition, and Circadian Phase in the Kestrel, Falco tinnunculus

    NARCIS (Netherlands)

    Daan, Serge; Masman, Dirkjan; Strijkstra, Arjen; Verhulst, Simon

    1989-01-01

    The relationship between body size and basal metabolic rate (BMR) in homeotherms has been treated in the literature primarily by comparison between species of mammals or birds. This paper focuses on the intraindividual changes in BMR when body mass (W) varies with different maintenance regimens. BMR

  16. Half-body irradiation-experience of size cases

    International Nuclear Information System (INIS)

    Andrade Carvalho, H. de; Aguilar, P.B.; Nadalin, W.; Weissberger, Y.; Scaff, L.A.M.; Lins, J.R.B.

    1990-01-01

    From 1983 to 1989, six patients with disseminated neoplastic disease non-responsive to conventional therapy were treated with palliative antialgic means. Three patients with breast cancer, two with prostate and one with Ewing's sarcoma received a total of eight treatments. The irradiation was first administered to the half-body presenting worst symptomatology. Total single dose of 800 cGy was delivered to the lower half-body and 600 cGy to the upper half-body. Pain relief was observed 24 to 48 hours after the irradiation in all patients. The haematological tolerance was good and deaths of these patients were not related to complications due to the radiation therapy. (author)

  17. Early-stage evolution of particle size distribution with Johnson's SB function due to Brownian coagulation

    International Nuclear Information System (INIS)

    Tang Hong; Lin Jianzhong

    2013-01-01

    The moment method can be used to determine the time evolution of particle size distribution due to Brownian coagulation based on the general dynamic equation (GDE). But the function form of the initial particle size distribution must be determined beforehand for the moment method. If the assumed function type of the initial particle size distribution has an obvious deviation from the true particle population, the evolution of particle size distribution may be different from the real evolution tendency. Thus, a simple and general method is proposed based on the moment method. In this method, the Johnson's S B function is chosen as a general distribution function to fit the initial distributions including the log normal (L-N), Rosin–Rammler (R-R), normal (N-N) and gamma distribution functions, respectively. Meanwhile, using the modified beta function to fit the L-N, R-R, N-N and gamma functions is also conducted as a comparison in order to present the advantage of the Johnson's S B function as the general distribution function. And then, the time evolution of particle size distributions using the Johnson's S B function as the initial distribution can be obtained by several lower order moment equations of the Johnson's S B function in conjunction with the GDE during the Brownian coagulation process. Simulation experiments indicate that fairly reasonable results of the time evolution of particle size distribution can be obtained with this proposed method in the free molecule regime, transition regime and continuum plus near continuum regime, respectively, at the early time stage of evolution. The Johnson's S B function has the ability of describing the early time evolution of different initial particle size distributions. (paper)

  18. Additive genetic variation in the craniofacial skeleton of baboons (genus Papio) and its relationship to body and cranial size.

    Science.gov (United States)

    Joganic, Jessica L; Willmore, Katherine E; Richtsmeier, Joan T; Weiss, Kenneth M; Mahaney, Michael C; Rogers, Jeffrey; Cheverud, James M

    2018-02-01

    Determining the genetic architecture of quantitative traits and genetic correlations among them is important for understanding morphological evolution patterns. We address two questions regarding papionin evolution: (1) what effect do body and cranial size, age, and sex have on phenotypic (V P ) and additive genetic (V A ) variation in baboon crania, and (2) how might additive genetic correlations between craniofacial traits and body mass affect morphological evolution? We use a large captive pedigreed baboon sample to estimate quantitative genetic parameters for craniofacial dimensions (EIDs). Our models include nested combinations of the covariates listed above. We also simulate the correlated response of a given EID due to selection on body mass alone. Covariates account for 1.2-91% of craniofacial V P . EID V A decreases across models as more covariates are included. The median genetic correlation estimate between each EID and body mass is 0.33. Analysis of the multivariate response to selection reveals that observed patterns of craniofacial variation in extant baboons cannot be attributed solely to correlated response to selection on body mass, particularly in males. Because a relatively large proportion of EID V A is shared with body mass variation, different methods of correcting for allometry by statistically controlling for size can alter residual V P patterns. This may conflate direct selection effects on craniofacial variation with those resulting from a correlated response to body mass selection. This shared genetic variation may partially explain how selection for increased body mass in two different papionin lineages produced remarkably similar craniofacial phenotypes. © 2017 Wiley Periodicals, Inc.

  19. Properties of three-body decay functions derived with time-like jet calculus beyond leading order

    International Nuclear Information System (INIS)

    Sugiura, Tetsuya

    2002-01-01

    Three-body decay functions in time-like parton branching are calculated using the jet calculus to the next-to-leading logarithmic (NLL) order in perturbative quantum chromodynamics (QCD). The phase space contributions from each of the ladder diagrams and interference diagrams are presented. We correct part of the results for the three-body decay functions calculated previously by two groups. Employing our new results, the properties of the three-body decay functions in the regions of soft partons are examined numerically. Furthermore, we examine the contribution of the three-body decay functions modified by the restriction resulting from the kinematical boundary of the phase space for two-body decay in the parton shower model. This restriction leads to some problems for the parton shower model. For this reason, we propose a new restriction introduced by the kinematical boundary of the phase space for two-body decay. (author)

  20. Reference man and woman more fully characterized: Variations on the basis of body size, age, sex, and race

    International Nuclear Information System (INIS)

    Ellis, K.J.

    1990-01-01

    Total body neutron activation analysis, prompt-gamma neutron activation analysis, and whole body counting have been used to determine the elemental composition of the human body. The total body elements measured were potassium, nitrogen, calcium, sodium, chlorine, and phosphorus. Total body water was also determined by the dilution principle using tritiated water. Observations were made in an adult US population that totaled 1374 and ranged in age from 20 to 90 yr. The dataset for the white population consisted of 175 males and 1134 females observations; for the black population, it consisted of 30 male and 35 female observations. The variation in the elemental composition of both males and females in any 5-yr age group was large and ranged up to 20% (SD). Age-, race-, sex-, and size-specific differences were evident. When equations were developed that predicted the elemental composition of the adult on the basis of age, weight, and height, the variation in the age groups was reduced approximately in half. Age-specific mean values for the 20- to 29-yr-old white population were also compared with values for the International Commission on Radiological Protection (ICRP)-23 Reference Man. The open-quotes averageclose quotes young adult male was larger than Reference Man; the in vivo data also indicated a larger skeletal mass, more lean tissues and body water, but lower body sodium. When in vivo prediction equations were used to adjust for size differences, good agreement was found between the expected values and those for Reference Man. The ICRP-23 does not contain elemental data for Reference Woman; therefore, the in vivo data in the present study provide the first estimates of body composition for Reference Woman

  1. Rootletin interacts with C-Nap1 and may function as a physical linker between the pair of centrioles/basal bodies in cells.

    Science.gov (United States)

    Yang, Jun; Adamian, Michael; Li, Tiansen

    2006-02-01

    Rootletin, a major structural component of the ciliary rootlet, is located at the basal bodies and centrosomes in ciliated and nonciliated cells, respectively. Here we investigated its potential role in the linkage of basal bodies/centrioles and the mechanism involved in such linkages. We show that rootletin interacts with C-Nap1, a protein restricted at the ends of centrioles and functioning in centrosome cohesion in interphase cells. Their interaction in vivo is supported by their colocalization at the basal bodies/centrioles and coordinated association with the centrioles during the cell cycle. Ultrastructural examinations demonstrate that rootletin fibers connect the basal bodies in ciliated cells and are present both at the ends of and in between the pair of centrioles in nonciliated cells. The latter finding stands in contrast with C-Nap1, which is present only at the ends of the centrioles. Transient expression of C-Nap1 fragments dissociated rootletin fibers from the centrioles, resulting in centrosome separation in interphase. Overexpression of rootletin in cells caused multinucleation, micronucleation, and irregularity of nuclear shape and size, indicative of defects in chromosome separation. These data suggest that rootletin may function as a physical linker between the pair of basal bodies/centrioles by binding to C-Nap1.

  2. Threat-level-dependent manipulation of signaled body size: dog growls' indexical cues depend on the different levels of potential danger.

    Science.gov (United States)

    Bálint, Anna; Faragó, Tamás; Miklósi, Ádám; Pongrácz, Péter

    2016-11-01

    Body size is an important feature that affects fighting ability; however, size-related parameters of agonistic vocalizations are difficult to manipulate because of anatomical constraints within the vocal production system. Rare examples of acoustic size modulation are due to specific features that enable the sender to steadily communicate exaggerated body size. However, one could argue that it would be more adaptive if senders could adjust their signaling behavior to the fighting potential of their actual opponent. So far there has been no experimental evidence for this possibility. We tested this hypothesis by exposing family dogs (Canis familiaris) to humans with potentially different fighting ability. In a within-subject experiment, 64 dogs of various breeds consecutively faced two threateningly approaching humans, either two men or two women of different stature, or a man and a woman of similar or different stature. We found that the dogs' vocal responses were affected by the gender of the threatening stranger and the dog owner's gender. Dogs with a female owner, or those dogs which came from a household where both genders were present, reacted with growls of lower values of the Pitch-Formant component (including deeper fundamental frequency and lower formant dispersion) to threatening men. Our results are the first to show that non-human animals react with dynamic alteration of acoustic parameters related to their individual indexical features (body size), depending on the level of threat in an agonistic encounter.

  3. Digestive enzymes and gut morphometric parameters of threespine stickleback (Gasterosteus aculeatus): Influence of body size and temperature.

    Science.gov (United States)

    Hani, Younes Mohamed Ismail; Marchand, Adrien; Turies, Cyril; Kerambrun, Elodie; Palluel, Olivier; Bado-Nilles, Anne; Beaudouin, Rémy; Porcher, Jean-Marc; Geffard, Alain; Dedourge-Geffard, Odile

    2018-01-01

    Determining digestive enzyme activity is of potential interest to obtain and understand valuable information about fish digestive physiology, since digestion is an elementary process of fish metabolism. We described for the first time (i) three digestive enzymes: amylase, trypsin and intestinal alkaline phosphatase (IAP), and (ii) three gut morphometric parameters: relative gut length (RGL), relative gut mass (RGM) and Zihler's index (ZI) in threespine stickleback (Gasterosteus aculeatus), and we studied the effect of temperature and body size on these parameters. When mimicking seasonal variation in temperature, body size had no effect on digestive enzyme activity. The highest levels of amylase and trypsin activity were observed at 18°C, while the highest IAP activity was recorded at 20°C. When sticklebacks were exposed to three constant temperatures (16, 18 and 21°C), a temporal effect correlated to fish growth was observed with inverse evolution patterns between amylase activity and the activities of trypsin and IAP. Temperature (in both experiments) had no effect on morphometric parameters. However, a temporal variation was recorded for both RGM (in the second experiment) and ZI (in both experiments), and the later was correlated to fish body mass.

  4. Digestive enzymes and gut morphometric parameters of threespine stickleback (Gasterosteus aculeatus): Influence of body size and temperature

    Science.gov (United States)

    Marchand, Adrien; Turies, Cyril; Kerambrun, Elodie; Palluel, Olivier; Bado-Nilles, Anne; Beaudouin, Rémy; Porcher, Jean-Marc; Geffard, Alain; Dedourge-Geffard, Odile

    2018-01-01

    Determining digestive enzyme activity is of potential interest to obtain and understand valuable information about fish digestive physiology, since digestion is an elementary process of fish metabolism. We described for the first time (i) three digestive enzymes: amylase, trypsin and intestinal alkaline phosphatase (IAP), and (ii) three gut morphometric parameters: relative gut length (RGL), relative gut mass (RGM) and Zihler’s index (ZI) in threespine stickleback (Gasterosteus aculeatus), and we studied the effect of temperature and body size on these parameters. When mimicking seasonal variation in temperature, body size had no effect on digestive enzyme activity. The highest levels of amylase and trypsin activity were observed at 18°C, while the highest IAP activity was recorded at 20°C. When sticklebacks were exposed to three constant temperatures (16, 18 and 21°C), a temporal effect correlated to fish growth was observed with inverse evolution patterns between amylase activity and the activities of trypsin and IAP. Temperature (in both experiments) had no effect on morphometric parameters. However, a temporal variation was recorded for both RGM (in the second experiment) and ZI (in both experiments), and the later was correlated to fish body mass. PMID:29614133

  5. Correlates of elemental-isotopic composition of stream fishes: the importance of land-use, species identity and body size.

    Science.gov (United States)

    Montaña, C G; Schalk, C M

    2018-04-01

    The isotopic (δ 13 C and δ 15 N) and stoichiometric (C:N:P) compositions of four fish species (Family Centrarchidae: Lepomis auritus, Lepomis cyanellus; Family Cyprinidae: Nocomis leptocephalus, Semotilus atromaculatus) were examined across four North Carolina Piedmont streams arrayed along an urbanization gradient. Both isotopic and stoichiometric composition of fishes appeared to track changes occurring in basal resource availability. Values of δ 13 C of basal resources and consumers were more enriched at the most urbanized streams. Similarly, basal resources and consumers were δ 15 N-enriched at more urbanized streams. Basal resource stoichiometry varied across streams, with periphyton being the most variable. Primary consumers stoichiometry also differed across streams. Intraspecific variation in fish stoichiometry correlated with the degree of urbanization, as the two cyprinids had higher N content and L. cyanellus had higher P content in more urbanized streams, probably due to enrichment of basal resources. Intrinsic factors, specifically species identity and body size also affected stoichiometric variation. Phosphorus (P) content increased significantly with body size in centrarchids, but not in cyprinids. These results suggest that although species identity and body size are important predictors of elemental stoichiometry, the complex nature of altered urban streams may yield imbalances in the elemental composition of consumers via their food resources. © 2018 The Fisheries Society of the British Isles.

  6. Impact of body size, nutrition and socioeconomic position in early life on the epigenome: a systematic review protocol.

    Science.gov (United States)

    Maddock, Jane; Wulaningsih, Wahyu; Hardy, Rebecca

    2017-07-05

    Body size, nutrition and socioeconomic position (SEP) in early life have been associated with a range of later life health outcomes. Epigenetic regulation is one mechanism through which these early life factors may impact later life health. The aim of this review protocol is to outline procedures to document the influence of body size, nutrition and SEP in early life on the epigenome. MEDLINE, Embase and BIOSIS will be systematically searched using pre-defined keywords. Additional studies will be identified through manual searching of reference lists. Two independent researchers will assess the eligibility and quality of each study, with disagreements being resolved through discussion or a third reviewer. Studies will be included if they have epigenetic markers measured either at the same time as, or after, the early life exposure and, have a measure of body size, nutrition or SEP in early life (up to 12 years), are in the English language and are from a sample of community-dwelling participants. This protocol will be used to collate the evidence for the effect of early life factors on the epigenome. Findings will form a component of a wider research study examining epigenetic responses to exposures in early life and over the life course and its impact on healthy ageing using data from population-based cohort studies. PROSPERO CRD42016050193.

  7. Pore size determination using normalized J-function for different hydraulic flow units

    Directory of Open Access Journals (Sweden)

    Ali Abedini

    2015-06-01

    Full Text Available Pore size determination of hydrocarbon reservoirs is one of the main challenging areas in reservoir studies. Precise estimation of this parameter leads to enhance the reservoir simulation, process evaluation, and further forecasting of reservoir behavior. Hence, it is of great importance to estimate the pore size of reservoir rocks with an appropriate accuracy. In the present study, a modified J-function was developed and applied to determine the pore radius in one of the hydrocarbon reservoir rocks located in the Middle East. The capillary pressure data vs. water saturation (Pc–Sw as well as routine reservoir core analysis include porosity (φ and permeability (k were used to develop the J-function. First, the normalized porosity (φz, the rock quality index (RQI, and the flow zone indicator (FZI concepts were used to categorize all data into discrete hydraulic flow units (HFU containing unique pore geometry and bedding characteristics. Thereafter, the modified J-function was used to normalize all capillary pressure curves corresponding to each of predetermined HFU. The results showed that the reservoir rock was classified into five separate rock types with the definite HFU and reservoir pore geometry. Eventually, the pore radius for each of these HFUs was determined using a developed equation obtained by normalized J-function corresponding to each HFU. The proposed equation is a function of reservoir rock characteristics including φz, FZI, lithology index (J*, and pore size distribution index (ɛ. This methodology used, the reservoir under study was classified into five discrete HFU with unique equations for permeability, normalized J-function and pore size. The proposed technique is able to apply on any reservoir to determine the pore size of the reservoir rock, specially the one with high range of heterogeneity in the reservoir rock properties.

  8. Heuristic method for determining outgoing waves in many-body wave functions

    International Nuclear Information System (INIS)

    Redish, E.F.; Tandy, P.C.; L'Huillier, M.

    1975-12-01

    A new and simple method is proposed for determining the kinds of outgoing waves present in a given many-body wave function. Whether any particular wave function contains ''hidden'' rearrangement components can be determined. 1 figure

  9. A Virtual Reality Full Body Illusion Improves Body Image Disturbance in Anorexia Nervosa.

    Directory of Open Access Journals (Sweden)

    Anouk Keizer

    Full Text Available Patients with anorexia nervosa (AN have a persistent distorted experience of the size of their body. Previously we found that the Rubber Hand Illusion improves hand size estimation in this group. Here we investigated whether a Full Body Illusion (FBI affects body size estimation of body parts more emotionally salient than the hand. In the FBI, analogue to the RHI, participants experience ownership over an entire virtual body in VR after synchronous visuo-tactile stimulation of the actual and virtual body.We asked participants to estimate their body size (shoulders, abdomen, hips before the FBI was induced, directly after induction and at ~2 hour 45 minutes follow-up. The results showed that AN patients (N = 30 decrease the overestimation of their shoulders, abdomen and hips directly after the FBI was induced. This effect was strongest for estimates of circumference, and also observed in the asynchronous control condition of the illusion. Moreover, at follow-up, the improvements in body size estimation could still be observed in the AN group. Notably, the HC group (N = 29 also showed changes in body size estimation after the FBI, but the effect showed a different pattern than that of the AN group.The results lead us to conclude that the disturbed experience of body size in AN is flexible and can be changed, even for highly emotional body parts. As such this study offers novel starting points from which new interventions for body image disturbance in AN can be developed.

  10. Rates of molecular evolution in tree ferns are associated with body size, environmental temperature, and biological productivity.

    Science.gov (United States)

    Barrera-Redondo, Josué; Ramírez-Barahona, Santiago; Eguiarte, Luis E

    2018-05-01

    Variation in rates of molecular evolution (heterotachy) is a common phenomenon among plants. Although multiple theoretical models have been proposed, fundamental questions remain regarding the combined effects of ecological and morphological traits on rate heterogeneity. Here, we used tree ferns to explore the correlation between rates of molecular evolution in chloroplast DNA sequences and several morphological and environmental factors within a Bayesian framework. We revealed direct and indirect effects of body size, biological productivity, and temperature on substitution rates, where smaller tree ferns living in warmer and less productive environments tend to have faster rates of molecular evolution. In addition, we found that variation in the ratio of nonsynonymous to synonymous substitution rates (dN/dS) in the chloroplast rbcL gene was significantly correlated with ecological and morphological variables. Heterotachy in tree ferns may be influenced by effective population size associated with variation in body size and productivity. Macroevolutionary hypotheses should go beyond explaining heterotachy in terms of mutation rates and instead, should integrate population-level factors to better understand the processes affecting the tempo of evolution at the molecular level. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

  11. Wide range of body composition measures are associated with cognitive function in community-dwelling older adults.

    Science.gov (United States)

    Won, Huiloo; Abdul Manaf, Zahara; Mat Ludin, Arimi Fitri; Shahar, Suzana

    2017-04-01

    Studies of the association between body composition, both body fat and body muscle, and cognitive function are rarely reported. The aim of the present study was to determine the association between a wide range of body composition measures with cognitive function in older adults. A total of 2322 Malaysian older adults aged 60 years and older were recruited using multistage random sampling in a population-based cross-sectional study. Out of 2322 older adults recruited, 2309 (48% men) completed assessments on cognitive function and body composition. Cognitive functions were assessed using the Malay version of the Mini-Mental State Examination, the Bahasa Malaysia version of Montreal Cognitive Assessment, Digit Span Test, Digit Symbol Test and Rey Auditory Verbal Learning Test. Body composition included body mass index, mid-upper arm circumference, waist circumference, calf circumference, waist-to-hip ratio, percentage body fat and skeletal muscle mass. The association between body composition and cognitive functions was analyzed using multiple linear regression. After adjustment for age, education years, hypertension, hypercholesterolemia, diabetes mellitus, depression, smoking status and alcohol consumption, we found that calf circumference appeared as a significant predictor for all cognitive tests among both men and women (P cognitive tests among women (P Cognitive Assessment among men (P older adults for optimal cognitive function. Geriatr Gerontol Int 2017; 17: 554-560. © 2016 Japan Geriatrics Society.

  12. The effect of personal grooming on self-perceived body image.

    Science.gov (United States)

    van Paasschen, J; Walker, S C; Phillips, N; Downing, P E; Tipper, S P

    2015-02-01

    Grooming behaviours, including the application of fragranced products, are thought to reflect a means of managing social impressions and self-image. Although application of deodorants has previously been shown to make individuals appear more confident to others, few studies have specifically examined the psychological effects of such rituals on the wearer. Here, we investigated how grooming behaviours affect self-perceived body image, a central component of an individual's self-image. In two separate experiments, using a psychophysical forced choice task, male and female participants with a normal Body Mass Index (BMI) indicated whether projected life-size images of their own body were bigger or smaller than their actual size. In the experimental condition, participants applied a fragranced deodorant before performing the task, whereas in the control condition, no product was applied. Our dependent measures were the point of subjective equality (PSE), the size at which participants report their body is subjectively equal to their actual body size, and the difference limen (DL), the amount of change in body size distortion necessary for it to be reliably detected. These measurements provide an index of attitudinal and perceptual components of body image, respectively. Both male and female participants who, at baseline, overestimated their body size, made significantly more accurate judgments about their body size, as measured by the PSE, following application of a fragranced deodorant or antiperspirant than they did in the control condition. This effect was seen in the absence of differences in perceptual sensitivity to changes in body size (DL) across groups and conditions. People who underestimated their body size did not show this effect. Of note, both male and female overestimators had a significantly larger BMI than underestimators. These results demonstrate that the attitudinal component of body image is malleable and can be influenced by everyday grooming

  13. Many-body localization in disorder-free systems: The importance of finite-size constraints

    Energy Technology Data Exchange (ETDEWEB)

    Papić, Z., E-mail: zpapic@perimeterinstitute.ca [School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT (United Kingdom); Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada); Stoudenmire, E. Miles [Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada); Abanin, Dmitry A. [Department of Theoretical Physics, University of Geneva, 24 quai Ernest-Ansermet, 1211 Geneva (Switzerland); Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada)

    2015-11-15

    Recently it has been suggested that many-body localization (MBL) can occur in translation-invariant systems, and candidate 1D models have been proposed. We find that such models, in contrast to MBL systems with quenched disorder, typically exhibit much more severe finite-size effects due to the presence of two or more vastly different energy scales. In a finite system, this can artificially split the density of states (DOS) into bands separated by large gaps. We argue for such models to faithfully represent the thermodynamic limit behavior, the ratio of relevant coupling must exceed a certain system-size depedent cutoff, chosen such that various bands in the DOS overlap one another. Setting the parameters this way to minimize finite-size effects, we study several translation-invariant MBL candidate models using exact diagonalization. Based on diagnostics including entanglement and local observables, we observe thermal (ergodic), rather than MBL-like behavior. Our results suggest that MBL in translation-invariant systems with two or more very different energy scales is less robust than perturbative arguments suggest, possibly pointing to the importance of non-perturbative effects which induce delocalization in the thermodynamic limit.

  14. A Virtual Reality Full Body Illusion Improves Body Image Disturbance in Anorexia Nervosa

    NARCIS (Netherlands)

    Keizer, Anouk; van Elburg, Annemarie; Helms, Rossa; Dijkerman, H Chris

    2016-01-01

    BACKGROUND: Patients with anorexia nervosa (AN) have a persistent distorted experience of the size of their body. Previously we found that the Rubber Hand Illusion improves hand size estimation in this group. Here we investigated whether a Full Body Illusion (FBI) affects body size estimation of

  15. Body size-dependent Cd accumulation in the zebra mussel Dreissena polymorpha from different routes.

    Science.gov (United States)

    Tang, Wen-Li; Evans, Douglas; Kraemer, Lisa; Zhong, Huan

    2017-02-01

    Understanding body size-dependent metal accumulation in aquatic organisms (i.e., metal allometry) is critical in interpreting biomonitoring data. While growth has received the most attention, little is known about controls of metal exposure routes on metal allometry. Here, size-dependent Cd accumulation in zebra mussels (Dreissena polymorpha) from different routes were investigated by exposing mussels to A.( 111 Cd spiked algae+ 113 Cd spiked river water) or B.( 111 Cd spiked sediments+ 113 Cd spiked river water). After exposure, 111 Cd or 113 Cd levels in mussel tissue were found to be negatively correlated with tissue weight, while Cd allometry coefficients (b values) were dependent on Cd exposure routes: -0.664 for algae, -0.241 for sediments and -0.379 for river water, compared to -0.582 in un-exposed mussels. By comparing different Cd exposure routes, we found that size-dependent Cd bioaccumulation from algae or river water could be more responsible for the overall size-dependent Cd accumulation in mussels, and the relative importance of the two sources was dependent on mussel size ranges: Cadmium obtained from algae (algae-Cd) was more important in size-dependent Cd accumulation in smaller mussels (tissue dry weight  5 mg). In contrast, sediment-Cd contributed only a small amount to Cd accumulation in zebra mussels and may have little effect on size-dependent Cd bioaccumulation. Our results suggest that size-dependent Cd accumulation in mussels could be largely affected by exposure routes, which should be considered when trying to interpret Cd biomonitoring data of zebra mussels. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Body-centred map in parietal eye fields - functional MRI study

    International Nuclear Information System (INIS)

    Brotchie, P.; Chen, D.Y.; Bradley, W.G.

    2002-01-01

    Full text: In order for us to interact with our environment we need to know where objects are around us, relative to our body. In monkeys, a body-centred map of visual space is known to exist within the parietal eye fields. This map is formed by the modulation of neuronal activity by eye and head position (Brotchie et al, Nature 1995; Synder et al, Nature 1998). In humans no map of body centred space has been demonstrated. By using functional MRI we have localised a region along the intraparietal sulcus which has properties similar to the parietal eye fields of monkeys (Brotchie et al, ISMRM, 2000). The aim of this study was to determine if activity in this region is modulated by head position, consistent with a body centered representation of visual space. Functional MRI was performed on 6 subjects performing simple visually guided saccades using a 1.5 Tesla GE Echospeed scanner. 10 scans were performed on the 6 subjects at left and right body orientations. Regions of interest were selected around the intraparietal sulcus proper (IPSP) of both hemispheres and voxels with BOLD signal which correlated with the paradigm (r>0.35) were selected for further analysis. Comparisons of percentage signal change were made between the left and right IPSP using Student t test. Of the 10 MRI examinations, 6 demonstrated statistically significant differences in the amount of signal change between left and right IPSP. In each of these 6 cases, the signal change was greater within the IPSP contralateral to the direction of head position relative to the body. This indicates a modulation of activity within the IPSP related to head position, most likely reflecting modulation of the underlying neuronal activity and suggests the existence of a body-centred encoding of space within the parietal eye fields of humans. Copyright (2002) Blackwell Science Pty Ltd

  17. Craniomandibular form and body size variation of first generation mouse hybrids: A model for hominin hybridization.

    Science.gov (United States)

    Warren, Kerryn A; Ritzman, Terrence B; Humphreys, Robyn A; Percival, Christopher J; Hallgrímsson, Benedikt; Ackermann, Rebecca Rogers

    2018-03-01

    Hybridization occurs in a number of mammalian lineages, including among primate taxa. Analyses of ancient genomes have shown that hybridization between our lineage and other archaic hominins in Eurasia occurred numerous times in the past. However, we still have limited empirical data on what a hybrid skeleton looks like, or how to spot patterns of hybridization among fossils for which there are no genetic data. Here we use experimental mouse models to supplement previous studies of primates. We characterize size and shape variation in the cranium and mandible of three wild-derived inbred mouse strains and their first generation (F 1 ) hybrids. The three parent taxa in our analysis represent lineages that diverged over approximately the same period as the human/Neanderthal/Denisovan lineages and their hybrids are variably successful in the wild. Comparisons of body size, as quantified by long bone measurements, are also presented to determine whether the identified phenotypic effects of hybridization are localized to the cranium or represent overall body size changes. The results indicate that hybrid cranial and mandibular sizes, as well as limb length, exceed that of the parent taxa in all cases. All three F 1 hybrid crosses display similar patterns of size and form variation. These results are generally consistent with earlier studies on primates and other mammals, suggesting that the effects of hybridization may be similar across very different scenarios of hybridization, including different levels of hybrid fitness. This paper serves to supplement previous studies aimed at identifying F 1 hybrids in the fossil record and to introduce further research that will explore hybrid morphologies using mice as a proxy for better understanding hybridization in the hominin fossil record. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Body frame size in school children is related to the amount of adipose tissue in different depots but not to adipose distribution.

    Science.gov (United States)

    Guzmán-de la Garza, Francisco J; González Ayala, Alejandra E; Gómez Nava, Marisol; Martínez Monsiváis, Leislie I; Salinas Martínez, Ana M; Ramírez López, Erik; Mathiew Quirós, Alvaro; Garcia Quintanilla, Francisco

    2017-09-10

    The main aim of this study was to test the hypothesis that body frame size is related to the amount of fat in different adipose tissue depots and to fat distribution in schoolchildren. Children aged between 5 and 10 years were included in this cross-sectional study (n = 565). Body frame size, adiposity markers (anthropometric, skinfolds thickness, and ultrasound measures), and fat distribution indices were analyzed. Correlation coefficients adjusted by reliability were estimated and analyzed by sex; the significance of the difference between two correlation coefficients was assessed using the Fisher z-transformation. The sample included primarily urban children; 58.6% were normal weight, 16.1% overweight, 19.6% obese, and the rest were underweight. Markers of subcutaneous adiposity, fat mass and fat-free mass, and preperitoneal adiposity showed higher and significant correlations with the sum of the biacromial + bitrochanteric diameter than with the elbow diameter, regardless of sex. The fat distribution conicity index presented significant but weak correlations; and visceral adipose tissue, hepatic steatosis, and the waist-for-hip ratio were not significantly correlated with body frame size measures. Body frame size in school children was related to the amount of adipose tissue in different depots, but not adipose distribution. More studies are needed to confirm this relationship and its importance to predict changes in visceral fat deposition during growth. © 2017 Wiley Periodicals, Inc.

  19. Unifying the functional diversity in natural and cultivated soils using the overall body-mass distribution of nematodes.

    Science.gov (United States)

    Mulder, Christian; Maas, Rob

    2017-11-28

    Sustainable use of our soils is a key goal for environmental protection. As many ecosystem services are supported belowground at different trophic levels by nematodes, soil nematodes are expected to provide objective metrics for biological quality to integrate physical and chemical soil variables. Trait measurements of body mass carried out at the individual level can in this way be correlated with environmental properties that influence the performance of soil biota. Soil samples were collected across 200 sites (4 soil types and 5 land-use types resulting in 9 combinations) during a long-term monitoring programme in the Netherlands and the functional diversity of nematode communities was investigated. Using three commonly used functional diversity indices applicable to single traits (Divergence, Evenness and Richness), a unified index of overall body-mass distribution is proposed to better illustrate the application of functional metrics as a descriptor of land use. Effects of land use and soil chemistry on the functional diversity of nematodes were demonstrated and a combination of environmental factors accounts for the low functional value of Scots Pine forest soils in comparison to the high functional value of heathland soils, whereas human factors account for the low functional and chemical values of arable fields. These findings show an unexpected high functional vulnerability of nematodes inhabiting clay-rich soils in comparison to sandy soils and support the notion that soil C:N ratio is a major driver of biodiversity. The higher the C:N ratio, the higher the overall diversity, as soil nematodes cope better with nutrient-poor agroecosystems under less intense fertilization. A trait-based way focusing on size distribution of nematodes is proposed to maintain environmental health by monitoring the overall diversity in soil biota, keeping agriculture and forestry sustainable.

  20. Elucidating mechanisms for insect body size: partial support for the oxygen-dependent induction of moulting hypothesis.

    Science.gov (United States)

    Kivelä, Sami M; Viinamäki, Sonja; Keret, Netta; Gotthard, Karl; Hohtola, Esa; Välimäki, Panu

    2018-01-25

    Body size is a key life history trait, and knowledge of its mechanistic basis is crucial in life history biology. Such knowledge is accumulating for holometabolous insects, whose growth is characterised and body size affected by moulting. According to the oxygen-dependent induction of moulting (ODIM) hypothesis, moult is induced at a critical mass at which oxygen demand of growing tissues overrides the supply from the tracheal respiratory system, which principally grows only at moults. Support for the ODIM hypothesis is controversial, partly because of a lack of proper data to explicitly test the hypothesis. The ODIM hypothesis predicts that the critical mass is positively correlated with oxygen partial pressure ( P O 2 ) and negatively with temperature. To resolve the controversy that surrounds the ODIM hypothesis, we rigorously test these predictions by exposing penultimate-instar Orthosia gothica (Lepidoptera: Noctuidae) larvae to temperature and moderate P O 2  manipulations in a factorial experiment. The relative mass increment in the focal instar increased along with increasing P O 2 , as predicted, but there was only weak suggestive evidence of the temperature effect. Probably owing to a high measurement error in the trait, the effect of P O 2  on the critical mass was sex specific; high P O 2  had a positive effect only in females, whereas low P O 2  had a negative effect only in males. Critical mass was independent of temperature. Support for the ODIM hypothesis is partial because of only suggestive evidence of a temperature effect on moulting, but the role of oxygen in moult induction seems unambiguous. The ODIM mechanism thus seems worth considering in body size analyses. © 2018. Published by The Company of Biologists Ltd.

  1. High diversity, low disparity and small body size in plesiosaurs (Reptilia, Sauropterygia from the Triassic-Jurassic boundary.

    Directory of Open Access Journals (Sweden)

    Roger B J Benson

    Full Text Available Invasion of the open ocean by tetrapods represents a major evolutionary transition that occurred independently in cetaceans, mosasauroids, chelonioids (sea turtles, ichthyosaurs and plesiosaurs. Plesiosaurian reptiles invaded pelagic ocean environments immediately following the Late Triassic extinctions. This diversification is recorded by three intensively-sampled European fossil faunas, spanning 20 million years (Ma. These provide an unparalleled opportunity to document changes in key macroevolutionary parameters associated with secondary adaptation to pelagic life in tetrapods. A comprehensive assessment focuses on the oldest fauna, from the Blue Lias Formation of Street, and nearby localities, in Somerset, UK (Earliest Jurassic: 200 Ma, identifying three new species representing two small-bodied rhomaleosaurids (Stratesaurus taylori gen et sp. nov.; Avalonnectes arturi gen. et sp. nov and the most basal plesiosauroid, Eoplesiosaurus antiquior gen. et sp. nov. The initial radiation of plesiosaurs was characterised by high, but short-lived, diversity of an archaic clade, Rhomaleosauridae. Representatives of this initial radiation were replaced by derived, neoplesiosaurian plesiosaurs at small-medium body sizes during a more gradual accumulation of morphological disparity. This gradualistic modality suggests that adaptive radiations within tetrapod subclades are not always characterised by the initially high levels of disparity observed in the Paleozoic origins of major metazoan body plans, or in the origin of tetrapods. High rhomaleosaurid diversity immediately following the Triassic-Jurassic boundary supports the gradual model of Late Triassic extinctions, mostly predating the boundary itself. Increase in both maximum and minimum body length early in plesiosaurian history suggests a driven evolutionary trend. However, Maximum-likelihood models suggest only passive expansion into higher body size categories.

  2. Unique associations between young adult men's emotional functioning and their body dissatisfaction and disordered eating.

    Science.gov (United States)

    Griffiths, Scott; Angus, Douglas; Murray, Stuart B; Touyz, Stephen

    2014-03-01

    Research on emotional functioning, body dissatisfaction, and disordered eating in males is predominated by studies of negative affect and emotion regulation. Other aspects of emotional functioning, namely emotion recognition and attentional biases toward emotional stimuli, have received little empirical attention. The present study investigated the unique associations between different aspects of men's emotional functioning and their disordered eating attitudes, muscularity dissatisfaction, and body fat dissatisfaction. Results from 132 male undergraduates showed that muscularity dissatisfaction was uniquely associated with both emotion regulation difficulties and an attentional bias toward rejecting faces. Body fat dissatisfaction was not uniquely associated with any aspect of emotional functioning. Disordered eating was uniquely associated with emotion regulation difficulties. Collectively, the results indicate differences in the patterns of associations between men's emotional functioning and their body dissatisfaction and disordered eating. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Obtaining the Varshni potential function using the 2-body Kaxiras–Pandey parameters

    Directory of Open Access Journals (Sweden)

    TEIK-CHENG LIM

    2009-12-01

    Full Text Available A generalized version of the Varshni potential function was adopted by Kaxiras and Pandey for describing the 2-body energy portion of multi-body condensed matter. The former’s simplicity and resemblance to a Morse potential allows faster computation while the latter’s greater number of parameters allows better curve-fitting of spectroscopic data. This paper shows one set of parameter conversion from the Varshni function to the 2-body portion of the Kaxiras–Pandey function, and vice versa two sets of parameter conversion. The latter two sets reveal good correlation between plotted curves, and were verified by the imposition of equal energy curvatures at equilibrium and equal energy integral from equilibrium to dissociation. These parameter conversions can also be attained more easily by equating the product of indices (for short range and the summation of index reciprocals (for long range.

  4. Condition-Dependent Trade-Off Between Weapon Size and Immunity in Males of the European Earwig.

    Science.gov (United States)

    Körner, Maximilian; Vogelweith, Fanny; Foitzik, Susanne; Meunier, Joël

    2017-08-11

    Investigating the expression of trade-offs between key life-history functions is central to our understanding of how these functions evolved and are maintained. However, detecting trade-offs can be challenging due to variation in resource availability, which masks trade-offs at the population level. Here, we investigated in the European earwig Forficula auricularia whether (1) weapon size trades off with three key immune parameters - hemocyte concentration, phenoloxidase and prophenoloxidase activity - and whether (2) expression and strength of these trade-offs depend on male body condition (body size) and/or change after an immune challenge. Our results partially confirmed condition dependent trade-offs between weapon size and immunity in male earwigs. Specifically, we found that after an immune challenge, weapon size trades off with hemocyte concentrations in low-condition, but not in good-condition males. Contrastingly, weapon size was independent of pre-challenge hemocyte concentration. We also found no trade-off between weapon size and phenoloxidase activity, independent of body condition and immune challenge. Overall, our study reveals that trade-offs with sexual traits may weaken or disappear in good-condition individuals. Given the importance of weapon size for male reproductive success, our results highlight how low-condition individuals may employ alternative life-history investment strategies to cope with resource limitation.

  5. Universal relationship connecting various two-body effective residual interactions

    International Nuclear Information System (INIS)

    Knuepfer, W.; Huber, M.G.

    1976-01-01

    Starting from a momentum space analysis of the two-body matrix elements, a relation has been established between the size of the model space actually used in a specific calculation and the relevant properties of the effective residual interaction. It turns out that the two-body transition density acts like a filter function on the Fourier transform of the force; it exhibits a distinct structure which clearly reflects the size and the detailed properties of the configuration space actually used. From an investigation of this filter function an equivalence criterion for different effective residual two-body interactions has been established both for closed and open shell nuclei. This result can be used to construct simple although realistic effective forces. As an example, a model for a separable residual interaction is proposed in which the corresponding parameters are being clearly related to the nuclear radius (i.e., the mass number), to the quantum numbers (i.e., the angular momentum) of the state under consideration and to the size of the configuration space used. For a number of examples this force has been applied successfully for the description of low energy properties of both closed and open shell nuclei

  6. Phylogenetic perspectives on reef fish functional traits.

    Science.gov (United States)

    Floeter, Sergio R; Bender, Mariana G; Siqueira, Alexandre C; Cowman, Peter F

    2018-02-01

    Functional traits have been fundamental to the evolution and diversification of entire fish lineages on coral reefs. Yet their relationship with the processes promoting speciation, extinction and the filtering of local species pools remains unclear. We review the current literature exploring the evolution of diet, body size, water column use and geographic range size in reef-associated fishes. Using published and new data, we mapped functional traits on to published phylogenetic trees to uncover evolutionary patterns that have led to the current functional diversity of fishes on coral reefs. When examining reconstructed patterns for diet and feeding mode, we found examples of independent transitions to planktivory across different reef fish families. Such transitions and associated morphological alterations may represent cases in which ecological opportunity for the exploitation of different resources drives speciation and adaptation. In terms of body size, reconstructions showed that both large and small sizes appear multiple times within clades of mid-sized fishes and that extreme body sizes have arisen mostly in the last 10 million years (Myr). The reconstruction of range size revealed many cases of disparate range sizes among sister species. Such range size disparity highlights potential vicariant processes through isolation in peripheral locations. When accounting for peripheral speciation processes in sister pairs, we found a significant relationship between labrid range size and lineage age. The diversity and evolution of traits within lineages is influenced by trait-environment interactions as well as by species and trait-trait interactions, where the presence of a given trait may trigger the development of related traits or behaviours. Our effort to assess the evolution of functional diversity across reef fish clades adds to the burgeoning research focusing on the evolutionary and ecological roles of functional traits. We argue that the combination of a

  7. Motor unit recruitment by size does not provide functional advantages for motor performance.

    Science.gov (United States)

    Dideriksen, Jakob L; Farina, Dario

    2013-12-15

    It is commonly assumed that the orderly recruitment of motor units by size provides a functional advantage for the performance of movements compared with a random recruitment order. On the other hand, the excitability of a motor neuron depends on its size and this is intrinsically linked to its innervation number. A range of innervation numbers among motor neurons corresponds to a range of sizes and thus to a range of excitabilities ordered by size. Therefore, if the excitation drive is similar among motor neurons, the recruitment by size is inevitably due to the intrinsic properties of motor neurons and may not have arisen to meet functional demands. In this view, we tested the assumption that orderly recruitment is necessarily beneficial by determining if this type of recruitment produces optimal motor output. Using evolutionary algorithms and without any a priori assumptions, the parameters of neuromuscular models were optimized with respect to several criteria for motor performance. Interestingly, the optimized model parameters matched well known neuromuscular properties, but none of the optimization criteria determined a consistent recruitment order by size unless this was imposed by an association between motor neuron size and excitability. Further, when the association between size and excitability was imposed, the resultant model of recruitment did not improve the motor performance with respect to the absence of orderly recruitment. A consistent observation was that optimal solutions for a variety of criteria of motor performance always required a broad range of innervation numbers in the population of motor neurons, skewed towards the small values. These results indicate that orderly recruitment of motor units in itself does not provide substantial functional advantages for motor control. Rather, the reason for its near-universal presence in human movements is that motor functions are optimized by a broad range of innervation numbers.

  8. Nutrient enrichment differentially affects body sizes of primary consumers and predators in a detritus-based stream

    Science.gov (United States)

    John M. Davis; Amy D. Rosemond; Sue L. Eggert; Wyatt F. Cross; J. Bruce. Wallace

    2010-01-01

    We assessed how a 5-yr nutrient enrichment affected the responses of different size classes of primary consumers and predators in a detritus-based headwater stream. We hypothesized that alterations in detritus availability because of enrichment would decrease the abundance and biomass of large-bodied consumers. In contrast, we found that 2 yr of enrichment increased...

  9. Lean body mass as a determinant of thyroid size

    NARCIS (Netherlands)

    Wesche, M. F.; Wiersinga, W. M.; Smits, N. J.

    1998-01-01

    Males have a larger thyroid gland than females, and this has been related to the difference in body weight. In view of the different body composition of men and women, we hypothesized that lean body mass is a better determinant of thyroid volume than body weight. A cross-sectional study in an area

  10. Neurocognitive Functioning in Young Adults with Subclinical Body Dysmorphic Disorder.

    Science.gov (United States)

    Blum, Austin W; Redden, Sarah A; Grant, Jon E

    2018-03-01

    Despite reasonable knowledge of body dysmorphic disorder (BDD), little is known of its cognitive antecedents. In this study, we evaluated executive functioning and decision-making in people at risk of developing BDD using neuropsychological tests. Participants were non-treatment seeking volunteers (18-29 years) recruited from the general community, and split into two groups: those "at risk" of developing BDD (N = 5) and controls (N = 82). Participants undertook the One-Touch Stockings of Cambridge, Cambridge Gamble and Spatial Working Memory tasks and were assessed with the Body Dysmorphic Disorder Questionnaire. Results showed that the at-risk subjects performed significantly worse on a measure of executive function, whereas measures of risk-seeking behavior, quality of decision-making, and spatial working memory were largely intact. The findings suggest that selective cognitive dysfunction may already be present in terms of executive functioning in those at risk of developing BDD, even before psychopathology arises.

  11. Modeling fractal structure of city-size distributions using correlation functions.

    Science.gov (United States)

    Chen, Yanguang

    2011-01-01

    Zipf's law is one the most conspicuous empirical facts for cities, however, there is no convincing explanation for the scaling relation between rank and size and its scaling exponent. Using the idea from general fractals and scaling, I propose a dual competition hypothesis of city development to explain the value intervals and the special value, 1, of the power exponent. Zipf's law and Pareto's law can be mathematically transformed into one another, but represent different processes of urban evolution, respectively. Based on the Pareto distribution, a frequency correlation function can be constructed. By scaling analysis and multifractals spectrum, the parameter interval of Pareto exponent is derived as (0.5, 1]; Based on the Zipf distribution, a size correlation function can be built, and it is opposite to the first one. By the second correlation function and multifractals notion, the Pareto exponent interval is derived as [1, 2). Thus the process of urban evolution falls into two effects: one is the Pareto effect indicating city number increase (external complexity), and the other the Zipf effect indicating city size growth (internal complexity). Because of struggle of the two effects, the scaling exponent varies from 0.5 to 2; but if the two effects reach equilibrium with each other, the scaling exponent approaches 1. A series of mathematical experiments on hierarchical correlation are employed to verify the models and a conclusion can be drawn that if cities in a given region follow Zipf's law, the frequency and size correlations will follow the scaling law. This theory can be generalized to interpret the inverse power-law distributions in various fields of physical and social sciences.

  12. GW-Bodies and P-Bodies Constitute Two Separate Pools of Sequestered Non-Translating RNAs.

    Directory of Open Access Journals (Sweden)

    Prajal H Patel

    Full Text Available Non-translating RNAs that have undergone active translational repression are culled from the cytoplasm into P-bodies for decapping-dependent decay or for sequestration. Organisms that use microRNA-mediated RNA silencing have an additional pathway to remove RNAs from active translation. Consequently, proteins that govern microRNA-mediated silencing, such as GW182/Gw and AGO1, are often associated with the P-bodies of higher eukaryotic organisms. Due to the presence of Gw, these structures have been referred to as GW-bodies. However, several reports have indicated that GW-bodies have different dynamics to P-bodies. Here, we use live imaging to examine GW-body and P-body dynamics in the early Drosophila melanogaster embryo. While P-bodies are present throughout early embryonic development, cytoplasmic GW-bodies only form in significant numbers at the midblastula transition. Unlike P-bodies, which are predominantly cytoplasmic, GW-bodies are present in both nuclei and the cytoplasm. RNA decapping factors such as DCP1, Me31B, and Hpat are not associated with GW-bodies, indicating that P-bodies and GW-bodies are distinct structures. Furthermore, known Gw interactors such as AGO1 and the CCR4-NOT deadenylation complex, which have been shown to be important for Gw function, are also not present in GW-bodies. Use of translational inhibitors puromycin and cycloheximide, which respectively increase or decrease cellular pools of non-translating RNAs, alter GW-body size, underscoring that GW-bodies are composed of non-translating RNAs. Taken together, these data indicate that active translational silencing most likely does not occur in GW-bodies. Instead GW-bodies most likely function as repositories for translationally silenced RNAs. Finally, inhibition of zygotic gene transcription is unable to block the formation of either P-bodies or GW-bodies in the early embryo, suggesting that these structures are composed of maternal RNAs.

  13. What prolongs a butterfly's life?: Trade-offs between dormancy, fecundity and body size.

    Directory of Open Access Journals (Sweden)

    Elena Haeler

    Full Text Available In butterflies, life span often increases only at the expense of fecundity. Prolonged life span, on the other hand, provides more opportunities for oviposition. Here, we studied the association between life span and summer dormancy in two closely related species of Palearctic Meadow Brown butterflies, the endemic Maniola nurag and the widespread M. jurtina, from two climatic provenances, a Mediterranean and a Central European site, and tested the relationships between longevity, body size and fecundity. We experimentally induced summer dormancy and hence prolonged the butterflies' life in order to study the effects of such a prolonged life. We were able to modulate longevity only in Mediterranean females by rearing them under summer photoperiodic conditions (light 16 h : dark 8 h, thereby more than doubling their natural life span, to up to 246 days. Central European individuals kept their natural average live span under all treatments, as did Mediterranean individuals under autumn treatment (light 11: dark 13. Body size only had a significant effect in the smaller species, M. nurag, where it affected the duration of dormancy and lifetime fecundity. In the larger species, M. jurtina, a prolonged adult life span did, surprisingly, not convey any fecundity loss. In M. nurag, which generally deposited fewer eggs, extended life had a fecundity cost. We conclude that Mediterranen M. jurtina butterflies have an extraordinary plasticity in aging which allows them to extend life span in response to adverse environmental conditions and relieve the time limitation on egg-laying while maintaining egg production at equal levels.

  14. Development of a modified cortisol extraction procedure for intermediately sized fish not amenable to whole-body or plasma extraction methods.

    Science.gov (United States)

    Guest, Taylor W; Blaylock, Reginald B; Evans, Andrew N

    2016-02-01

    The corticosteroid hormone cortisol is the central mediator of the teleost stress response. Therefore, the accurate quantification of cortisol in teleost fishes is a vital tool for addressing fundamental questions about an animal's physiological response to environmental stressors. Conventional steroid extraction methods using plasma or whole-body homogenates, however, are inefficient within an intermediate size range of fish that are too small for phlebotomy and too large for whole-body steroid extractions. To assess the potential effects of hatchery-induced stress on survival of fingerling hatchery-reared Spotted Seatrout (Cynoscion nebulosus), we developed a novel extraction procedure for measuring cortisol in intermediately sized fish (50-100 mm in length) that are not amenable to standard cortisol extraction methods. By excising a standardized portion of the caudal peduncle, this tissue extraction procedure allows for a small portion of a larger fish to be sampled for cortisol, while minimizing the potential interference from lipids that may be extracted using whole-body homogenization procedures. Assay precision was comparable to published plasma and whole-body extraction procedures, and cortisol quantification over a wide range of sample dilutions displayed parallelism versus assay standards. Intra-assay %CV was 8.54%, and average recovery of spiked samples was 102%. Also, tissue cortisol levels quantified using this method increase 30 min after handling stress and are significantly correlated with blood values. We conclude that this modified cortisol extraction procedure provides an excellent alternative to plasma and whole-body extraction procedures for intermediately sized fish, and will facilitate the efficient assessment of cortisol in a variety of situations ranging from basic laboratory research to industrial and field-based environmental health applications.

  15. Treadmill Exercise with Increased Body Loading Enhances Post Flight Functional Performance

    Science.gov (United States)

    Bloomberg, J. J.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Laurie, S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Peters, B. T.; hide

    2014-01-01

    The goals of the Functional Task Test (FTT) study were to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. Ultimately this information will be used to assess performance risks and inform the design of countermeasures for exploration class missions. We have previously shown that for Shuttle, ISS and bed rest subjects functional tasks requiring a greater demand for dynamic control of postural equilibrium (i.e. fall recovery, seat egress/obstacle avoidance during walking, object translation, jump down) showed the greatest decrement in performance. Functional tests with reduced requirements for postural stability (i.e. hatch opening, ladder climb, manual manipulation of objects and tool use) showed little reduction in performance. These changes in functional performance were paralleled by similar decrements in sensorimotor tests designed to specifically assess postural equilibrium and dynamic gait control. The bed rest analog allows us to investigate the impact of axial body unloading in isolation on both functional tasks and on the underlying physiological factors that lead to decrements in performance and then compare them with the results obtained in our space flight study. These results indicate that body support unloading experienced during space flight plays a central role in postflight alteration of functional task performance. Given the importance of body-support loading we set out to determine if there is a relationship between the load experienced during inflight treadmill exercise (produced by a harness and bungee system) and postflight functional performance. ISS crewmembers (n=13) were tested using the FTT protocol before and after 6 months in space. Crewmembers were tested three times before flight, and on 1, 6, and 30 days after landing. To determine how differences in body

  16. Soot Particle Size Distribution Functions in a Turbulent Non-Premixed Ethylene-Nitrogen Flame

    KAUST Repository

    Boyette, Wesley

    2017-02-21

    A scanning mobility particle sizer with a nano differential mobility analyzer was used to measure nanoparticle size distribution functions in a turbulent non-premixed flame. The burner utilizes a premixed pilot flame which anchors a C2H4/N2 (35/65) central jet with ReD = 20,000. Nanoparticles in the flame were sampled through a N2-filled tube with a 500- μm orifice. Previous studies have shown that insufficient dilution of the nanoparticles can lead to coagulation in the sampling line and skewed particle size distribution functions. A system of mass flow controllers and valves were used to vary the dilution ratio. Single-stage and two-stage dilution systems were investigated. A parametric study on the effect of the dilution ratio on the observed particle size distribution function indicates that particle coagulation in the sampling line can be eliminated using a two-stage dilution process. Carbonaceous nanoparticle (soot) concentration particle size distribution functions along the flame centerline at multiple heights in the flame are presented. The resulting distributions reveal a pattern of increasing mean particle diameters as the distance from the nozzle along the centerline increases.

  17. Soot Particle Size Distribution Functions in a Turbulent Non-Premixed Ethylene-Nitrogen Flame

    KAUST Repository

    Boyette, Wesley; Chowdhury, Snehaunshu; Roberts, William L.

    2017-01-01

    A scanning mobility particle sizer with a nano differential mobility analyzer was used to measure nanoparticle size distribution functions in a turbulent non-premixed flame. The burner utilizes a premixed pilot flame which anchors a C2H4/N2 (35/65) central jet with ReD = 20,000. Nanoparticles in the flame were sampled through a N2-filled tube with a 500- μm orifice. Previous studies have shown that insufficient dilution of the nanoparticles can lead to coagulation in the sampling line and skewed particle size distribution functions. A system of mass flow controllers and valves were used to vary the dilution ratio. Single-stage and two-stage dilution systems were investigated. A parametric study on the effect of the dilution ratio on the observed particle size distribution function indicates that particle coagulation in the sampling line can be eliminated using a two-stage dilution process. Carbonaceous nanoparticle (soot) concentration particle size distribution functions along the flame centerline at multiple heights in the flame are presented. The resulting distributions reveal a pattern of increasing mean particle diameters as the distance from the nozzle along the centerline increases.

  18. Isointegral analysis of body surface maps for the assessment of location and size of myocardial infarction

    International Nuclear Information System (INIS)

    Tonooka, I.; Kubota, I.; Watanabe, Y.; Tsuiki, K.; Yasui, S.

    1983-01-01

    To estimate the location and size of myocardial infarction (MI), an isointegral mapping technique was adopted from among various body surface electrocardiographic mapping techniques. QRS isointegral and departure maps were made in 35 patients with MI. These patients were separated into 3 groups, based on the location of MI: anterior, inferior, and anterior plus inferior. The severity and location of MI were estimated by thallium-201 myocardial perfusion imaging and the degree of scintigraphic defect was represented by a defect score. The extent of MI was expected to be reflected on the QRS isointegral maps as a distribution of negative QRS complex time-integral values. However, the extent and the location of MI were hardly detectable by the original maps. A departure mapping technique was then devised to observe the distribution of departure index on the body surface. Particular attention was given to the area where the departure index was less than -2, and this area was expected to reflect the location and size of specific abnormality of isointegral map due to MI. There were strong correlations between departure area and defect score in the anterior and inferior MI cases (r . 0.88 and r . 0.79, respectively). However, patients with anterior MI plus inferior MI showed no such correlation. Q-wave mapping was compared with QRS isointegral mapping, and QRS isointegral mapping was found to be more accurate in the estimation of the location and size of MI than Q wave mapping. Thus, QRS isointegral mapping, especially departure mapping, is more useful and convenient for detecting the location and size of MI than methods such as isopotential and Q wave mapping

  19. Chromosomal inversions effect body size and shape in different breeding resources in Drosophila buzzatii.

    Science.gov (United States)

    Fernández Iriarte, P J; Norry, F M; Hasson, E R

    2003-07-01

    The cactophilic Drosophila buzzatii provides an excellent model for the study of reaction norms across discrete environments because it breeds on rotting tissues (rots) of very different cactus species. Here we test the possible effects of second chromosome inversions on body size and shape (wing loading) across suitable natural breeding substrates. Using homokaryotypic stocks derived from several lines homozygous for four naturally occurring chromosomal inversions, we show that arrangements significantly affect size-related traits and wing loading. In addition, karyotypes show differing effects, across natural breeding resources, for wing loading. The 2st and 2jz(3) arrangements decrease and the 2j arrangement increases wing loading. For thorax length and wing loading, karyotypic correlations across host plants are slightly lower in females than in males. These results support the hypothesis that these traits have a genetic basis associated with the inversion polymorphism.

  20. Learning to use a body-powered prosthesis: changes in functionality and kinematics.

    Science.gov (United States)

    Huinink, Laura H B; Bouwsema, Hanneke; Plettenburg, Dick H; van der Sluis, Corry K; Bongers, Raoul M

    2016-10-07

    Little is known about action-perception learning processes underlying prosthetic skills in body-powered prosthesis users. Body-powered prostheses are controlled through a harness connected by a cable that might provide for limited proprioceptive feedback. This study aims to test transfer of training basic tasks to functional tasks and to describe the changes over time in kinematics of basic tasks of novice body-powered prosthesis users. Thirty able-bodied participants and 17 controls participated in the study, using a body-powered prosthetic simulator. Participants in the training group were divided over four groups and practiced during a 2-week-period either direct grasping, indirect grasping, fixation, or a combination of these tasks. Deformable objects with different compliances had to be manipulated while kinematic variables and grip force control were assessed. Functional performance was measured with the Southampton Hand Assessment Procedure (SHAP) prior to and after the training sessions, and after 2 weeks and 3 months retention. The control group only performed the SHAP tests. All four training groups and the control group improved on the SHAP, also after a period of non-use. Type of training had a small but significant influence on the improvements of the SHAP score. On a kinematic level movement times decreased and hook closing velocities increased over time. The indirect grasping group showed significantly shorter plateau times than the other training groups. Grip force control only improved a little over training. Training action-perception couplings of body-powered prosthesis in basic tasks transferred to functional tasks and this lasted after a period of non-use. During training movement times decreased and the indirect grasping group showed advantages. It is advisable to start body-powered training with indirect grasping tasks but also to practice hook-object orientations.