Body size
Dotaz
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- MeSH
- finanční podpora výzkumu jako téma MeSH
- lidé MeSH
- lidské tělo MeSH
- osobní uspokojení MeSH
- percepce velikosti MeSH
- představa o vlastním těle MeSH
- průzkumy a dotazníky MeSH
- psychologie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- přehledy MeSH
- srovnávací studie MeSH
We test whether locomotor posture is associated with body mass and lower limb length in humans and explore how body size and posture affect net joint moments during walking. We acquired gait data for 24 females and 25 males using a three-dimensional motion capture system and pressure-measuring insoles. We employed the general linear model and commonality analysis to assess the independent effect of body mass and lower limb length on flexion angles at the hip, knee, and ankle while controlling for sex and velocity. In addition, we used inverse dynamics to model the effect of size and posture on net joint moments. At early stance, body mass has a negative effect on knee flexion (p < 0.01), whereas lower limb length has a negative effect on hip flexion (p < 0.05). Body mass uniquely explains 15.8% of the variance in knee flexion, whereas lower limb length uniquely explains 5.4% of the variance in hip flexion. Both of the detected relationships between body size and posture are consistent with the moment moderating postural adjustments predicted by our model. At late stance, no significant relationship between body size and posture was detected. Humans of greater body size reduce the flexion of the hip and knee at early stance, which results in the moderation of net moments at these joints.
- MeSH
- algoritmy MeSH
- biologické modely MeSH
- biomechanika MeSH
- chůze (způsob) fyziologie MeSH
- chůze fyziologie MeSH
- dolní končetina fyziologie MeSH
- dospělí MeSH
- hlezenní kloub fyziologie MeSH
- index tělesné hmotnosti MeSH
- kolenní kloub fyziologie MeSH
- koleno fyziologie MeSH
- kotník fyziologie MeSH
- kyčelní kloub fyziologie MeSH
- lidé MeSH
- lineární modely MeSH
- mladý dospělý MeSH
- postura těla fyziologie MeSH
- rozsah kloubních pohybů fyziologie MeSH
- velikost těla fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: 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. RESULTS: 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. CONCLUSIONS: 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.
- MeSH
- larva anatomie a histologie fyziologie MeSH
- ocas anatomie a histologie fyziologie MeSH
- plavání MeSH
- potravní řetězec * MeSH
- Salamandridae anatomie a histologie růst a vývoj fyziologie MeSH
- teplota MeSH
- vážky růst a vývoj fyziologie MeSH
- velikost těla MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: The objective of the study was to determine whether exposure of pregnant women to stresses caused by World War II (WWII) negatively affected pregnancy and perinatal outcomes. METHODS: Individual medical documents deposited in the Gynaecology and Obstetrics Clinic of Medical University, Poznań (1934-1943; N = 7058) were evaluated. These were divided into two birth cohorts: before WWII and during it. Frequency tables were constructed for the numbers of pregnancy outcomes: miscarriages, stillbirths, live births, and neonatal deaths, according to the period of birth and sex of a child. The numbers of recorded days were standardized and the numbers of cases per day were computed. Statistical differences in the averages (medians) between periods and years under study were tested. Birth weight, length, and body mass index (BMI) were compared according to the periods related to WWII. RESULTS: Significant differences in proportions of males, females, and subjects with unknown sex were found between the periods: a higher proportion of males and different structure of/within negative outcomes were found during WWII. Children born during WWII were heavier and longer than those born before it. CONCLUSIONS: As an explanation, adverse conditions of WWII, related to the psychological stress and food shortages, could have influenced greater elimination of fetuses and neonates of male sex during pregnancy and shortly after delivery. Higher average body size in newborns recorded during WWI could be explained by a hidden process of increased early prenatal mortality of weaker individuals, differences in average gestation length between the periods, differences in parity, or some undocumented differences in social/ethnic composition of the sample.
- MeSH
- 2. světová válka * MeSH
- index tělesné hmotnosti * MeSH
- lidé MeSH
- novorozenec MeSH
- porod MeSH
- porodní hmotnost * MeSH
- roční období MeSH
- sexuální faktory MeSH
- velikost těla MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Polsko MeSH
The relationship between two measures of excess body weight, body mass index (BMI) and body size score, and risk of pancreatic cancer was examined among 574 pancreatic cancer cases and 596 frequency-matched controls from the Czech Republic and Slovakia enrolled between 2004 and 2009. Analyses using multivariable logistic regression showed an increased risk of pancreatic cancer associated with elevated quartiles of BMI at ages 20 [fourth quartile: odds ratio (OR) = 1.79, 95% confidence interval (CI): 1.23, 2.61] and 40 (fourth quartile: OR = 1.57, 95% CI: 1.09, 2.27) compared to the lowest quartile. Consistent results were observed for body size score at ages 20 (high versus low: OR = 1.66, 95% CI: 1.08, 2.57) and 40 (medium versus low: OR = 1.36, 95% CI: 1.00, 1.86), but no association was found for BMI and body size score at 2 years before the interview. Stronger risk estimates for BMI were observed in males than females, particularly at age 20, but the analysis of body size yielded similar estimates by sex. When considering excess body weight at both ages 20 and 40 jointly, the highest risk estimates were observed among subjects with elevated levels at both time periods in the analysis of BMI (OR = 1.86, 95% CI: 1.32, 2.62) and body size (OR = 1.53, 95% CI: 1.09, 2.13). These findings, based on two different measures, provide strong support for an increased risk of pancreatic cancer associated with excess body weight, possibly strongest during early adulthood. Copyright 2011 UICC.
- MeSH
- dospělí MeSH
- index tělesné hmotnosti * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- nádory slinivky břišní * epidemiologie MeSH
- rizikové faktory MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- studie případů a kontrol MeSH
- tělesná hmotnost MeSH
- velikost těla * MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Česká republika MeSH
- Slovenská republika MeSH
Blood cell morphology and count are not uniform across species. Recently, between-species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa, and this finding was interpreted in the context of the metabolic theory. In the present study, we examined the numbers and the size of blood cells in 2 species of monitor lizards, the mangrove-dwelling monitor (Varanus indicus) and the savannah monitor (V. exanthematicus), and we compared these traits in individuals of different body size. The results revealed that during the course of ontogeny, the size of red blood cells increases with body mass. Because the mass-specific metabolic rate decreases with body size and the cell volume-to-surface ratio decreases with the cell size, changes in the erythrocyte size might be the result of oxygen transport adjustment.
- MeSH
- bazální metabolismus fyziologie MeSH
- druhová specificita MeSH
- erytrocyty cytologie fyziologie MeSH
- ještěři anatomie a histologie klasifikace fyziologie MeSH
- krevní buňky cytologie fyziologie MeSH
- leukocyty cytologie fyziologie MeSH
- spotřeba kyslíku fyziologie MeSH
- velikost buňky * MeSH
- velikost těla * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
Structural body size and adult feeding conditions seem to be important determinants of fitness in income breeding species. However, little is known about the relative importance of structural body size and nutritional state on fecundity and winter survival in carabids. In this study, two separate experiments were performed. The effects of the structural body size of females (expressed as the length of the elytra and the width of the pronotum) and the effect of starvation on the fecundity of the ground beetle Anchomenus dorsalis (Pontoppidan, 1763) were investigated in the "fecundity experiment." The influence of structural body size, feeding conditions (full, partial, or no feeding) before the winter, and behavior during the winter (burrowing into the substrate) on winter survival in A. dorsalis females were studied in the "overwintering experiment." Egg production was positively influenced by both the structural body size of females and adult feeding. The effect of structural body size on the number of eggs laid outweighed the effect of feeding. However, the total fecundity (the number of eggs laid plus the number of mature eggs in ovaries) were more strongly affected by feeding in comparison to the structural body size of females. Interestingly, there was no significant effect of structural body size, feeding before winter, or behavior during winter on the survival of A. dorsalis females during the winter. However, our overwintering results could be affected by extreme weather conditions throughout experimental season and by the experimental design, which is discussed in detail.
- MeSH
- brouci fyziologie MeSH
- chování zvířat MeSH
- fertilita fyziologie MeSH
- fyziologie výživy zvířat * MeSH
- kladení vajíček MeSH
- ovum MeSH
- roční období MeSH
- velikost těla * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
It is supposed that body size serves as an important cue in the recognition of relevant stimuli in nature. As predators of varying body size pose differing levels of threat, their potential prey should be able to discriminate between them. We tested the reaction of great tits (Parus major) to the dummies of their common predator (the European sparrowhawk-Accipiter nisus) in natural and reduced body sizes under laboratory conditions. All of the tested dummies possessed local raptor-specific features (hooked beak, claws with talons, and conspicuous eyes), but differed in global species-specific features: body size (large - the size of a sparrowhawk, small - the size of a great tit) and colouration (sparrowhawk, great tit, robin, and pigeon). The sparrowhawk-coloured dummies evoked fear regardless of their size while both great tit- and pigeon-coloured dummies evoked no fear reaction. The body size was used as the cue only for the discrimination of the robin-coloured dummies. The differences in reactions to the dummies with robin colouration (species unimportant to the great tits) could be explained as that the tits are able to recognize these birds in nature, but not so undoubtedly as the predator or the conspecific.
