Does a person's body size and the application type influence healthcare students' perceptions of technologies to promote physical activity? Findings from a cross-sectional study.

BACKGROUND: Recent evidence suggests that weight bias may be pervasive, even among health professionals specialized in obesity, including healthcare students. Technology-based physical activity interventions are promising for people with obesity, specifically when they are theory-driven (e.g., autonomy-supportive as described by self-determination theory). However, perceptions of these technologies have been understudied among healthcare students and professionals. OBJECTIVE: The purpose of this study was to examine the influence of a person's body size based on body mass index and technology type on healthcare students' perceptions. DESIGN: This is a cross-sectional, experimental study. PARTICIPANTS AND METHODS: Five hundred and two healthcare students (360 females, 142 males; mean age = 23.3, SD = 5.0) were randomly exposed to one of four scenarios that manipulated a hypothetical person's body mass index (22 kg/m2 vs. 42 kg/m2) and a technology-based physical activity type based on self-determination theory (autonomy-supportive app vs. controlling app). They then completed measures of their perceptions of the person's app acceptability and self-efficacy and of their intention to recommend the app. Multivariate and univariate analyses of covariance were performed. RESULTS: Students exposed to the larger-bodied people (42 kg/m2) versus the smaller-bodied people (22 kg/m2) perceived a lower level of person's app acceptability (i.e., higher social influence and less enjoyment in using the app), as well as a lower level of self-efficacy to use the technology. Students exposed to the controlling app were more likely to recommend it compared to those exposed to the autonomy-supportive app. CONCLUSIONS: These results suggest that healthcare students' attitudes may be negatively influenced by explicit weight bias. Also, in contrast to self-determination theory precepts, a controlling app may be more frequently recommended. Further study of healthcare students' implicit attitudes toward technology is needed.

Indirect costs of reproduction and the tradeoff between offspring size and number: a framework illustrated by fitness costs and benefits of ovarian fluid.

The theory describing the evolution of offspring size often assumes that the production cost per unit volume is the same for small and large offspring. However, this may not be true if indirect costs of reproduction (e.g., material and energetic costs of supporting offspring development) scale disproportionately with offspring size. Here we show how direct and indirect costs of reproduction can be explicitly modeled within the Smith-Fretwell framework and how observations of size-number relationships can thus be used to evaluate indirect costs. We applied this analysis to measures of egg volume and fecundity for over 300 individuals of a coastal fish species and found that the tradeoff was much stronger than the expected inverse (fecundity scaled with volume-1.843). Larger offspring were thus more expensive to produce. For our study species, an important indirect cost was that larger eggs were accompanied by disproportionately more ovarian fluid. Calorimetry and removal experiments were used to further measure both the energetic costs and fitness benefits of ovarian fluid. In addition, we show that indirect costs of reproduction can intensify size-number tradeoffs in a variety of fishes. Indirect costs of reproduction can be large and may therefore play an important role in the evolution of offspring size.

Variation in body size and weight status among Hindu and Muslim Indian males born in the 1890s through the 1950s.

Hindus and Muslims represent the two largest religions in India, and also differ in nutritional status, health-related habits and standard of living associated with economic disparities. In this context, the present study considered estimated secular changes in body size, proportions, and weight status among Hindu and Muslim Indian men. The data are from anthropological surveys in the 1970s which included measurements of height, weight and sitting height of 43,950 males 18-84 years (birth years 1891-1957). Leg length was estimated; the BMI and sitting height/height ratio were calculated. Heights of men 35 + years were adjusted for estimated height loss with age. Weight status was also classified relative to WHO criteria for the BMI. Anthropometric characteristics of the two groups were compared with MANCOVA with age and geographic region as covariates. Linear regression of height on year of birth was also used to estimate secular change in each group. Heights, weights, and BMIs tended to be, on average, greater among Muslim than Hindu men at most ages, while distributions by weight status between groups were negligible. Sitting height was greater among Muslim men but estimated leg length did not differ between groups; the sitting height/height ratio thus suggested proportionally shorter legs among Muslim men. Results of the regression analyses indicated negligible differences in secular change between groups across the total span of birth years but indicated a decline in adjusted heights of men in both groups born between 1891 through 1930s and little secular change among those born in the 1930s through 1957. The variation in heights, weights and BMIs between Muslim and Hindu men at most ages suggested variation in socio-economic status and dietary habits between the groups, whereas the negligible estimated secular changes in height between groups likely reflected economic, social, and nutritional conditions during the interval of British rule and the transition to independence.

Secular trends in height, weight, and body mass index in the context of economic and political transformations in Russia from 1885 to 2021.

OBJECTIVES: To study and analyze the impact of socio-economic factors on secular changes in height, weight, and body mass index (BMI) among Moscow's youth over the time interval from the late 19th-early 20th century to the present. METHODS: Anthropometric data, including height, weight, and BMI, were collected through surveys conducted on youths aged 17-20 years in Moscow from the 1880s for males and from the 1920s for females to the present. The dataset includes information on 6434 individuals surveyed from 2000 to 2019, as well as previously published mean values. Economic development indicators, such as gross domestic product (GDP) per capita, monthly average income per capita, and the Gini coefficient, were examined to analyze the association between secular trends in body size and socio-economic conditions. RESULTS: A positive secular trend in height and weight has been observed among Moscow's youth from the early 20th century to the present. Substantial increases in height occurred during the second half of the previous century, stabilizing in the 2000s. Over the analyzed period, both average body weight and BMI values showed a consistent rise. The pattern for BMI exhibited a U-shaped trend, with a decline from the 1970s to the mid-1990s, followed by a subsequent increase. Strong correlations were found between the secular changes in body size among Moscow's youth and temporal fluctuations in key socio-economic indicators, including GDP per capita, monthly average income per capita, and the Gini coefficient. CONCLUSION: The study demonstrates the significant influence of socio-economic conditions on intergenerational changes in body size, as evidenced by the positive secular trend in physique indicators (height, weight, and BMI) among Moscow's youth.

Potential biopsychosocial factors mediating/moderating the relationship between depressive symptoms and body size among children and adolescents: A systematic review.

The prevalence of depression and obesity in the pediatric population has increased along with multiple adverse health outcomes in later life. However, the mechanisms underlying the bidirectional relationship between obesity and depression have not yet been clarified. We aim to systematically summarize the literature reporting on mediational or moderational biopsychosocial factors in the relationship between depression and body size among children and adolescents. Four electronic databases (PubMed, Web of Science, PsycINFO, and PsychArticles) were systematically searched from inception until December 23, 2021, and subsequently updated until June 9, 2023. The study protocol was registered with PROSPERO (CRD42022301475). A total of 36 unique records reporting 152,513 children and adolescents meeting the inclusion criteria were identified. The results indicate that disparate psychological variables (e.g., body image, victimization and bullying, eating disorders, and sleep problems) may mediate the bidirectional relationship between depressive symptoms and body size. Moreover, the mediational/moderational effect of biological factors has not been well established. The moderational effect of social factors was inconsistently reported. Future research should aim to identify and characterize factors that may impact the bidirectional relationship between depression and obesity to inform prevention intervention strategies for affected children and adolescents.

The macroevolutionary dynamics of mammalian sexual size dimorphism.

Sexual size dimorphism (SSD) is a common phenomenon across the animal kingdom. Mammals are unusual in primarily displaying male-biased SSD, where males of a species are typically larger than females. The driving factors behind the evolution of this SSD have been much debated, with popular hypotheses invoking the influence of mating system and social organization via sexual selection, dietary niche divergence and broad-scale correlations with body size (Rensch's rule). Here, we investigate the macroevolutionary origins and maintenance of SSD among mammals, using phylogenetic general mixed linear models and a comprehensive global dataset to evaluate correlations of diet, body mass, seasonality, social organization and mating system with SSD type. We find that SSD as a whole is lost at a greater rate than it is gained, with female-biased SSD being particularly unstable. Non-monogamous mating systems, vertebrate prey consumption and temperature seasonality correlate with male-biased SSD, while polyandry correlates with female-biased SSD, and both types of SSD are positively correlated with body mass. This is in partial contrast to the predictions of Rensch's rule, which predicts that female-biased SSD would correlate negatively with body size. Taken together, our results highlight the importance of considering multiple ecological and social drivers when evaluating the macroevolutionary trajectory of sex differences in body size.

Transgenerational plasticity of exploratory behavior and a hidden cost of mismatched risk environments between parental sexes.

We require a better understanding of the relative contribution of different modes of non-genetic inheritance in behavioral trait development. Thus, we investigate variation in exploratory behavior, which is ecologically relevant and a target of selection. The metabolic hypothesis predicts exploratory behavior to be size-dependent across taxa. This size-dependency is cancelled out under high perceived risk, allowing us to determine the transgenerationally integrated estimated level of risk. Using fathead minnows Pimephales promelas, we manipulated perceived risk in mothers, fathers, caring males and offspring through continuous exposure to either conspecific alarm cues or to a control water treatment. In 1000 four-month old offspring, we determined body sizes and exploratory behavior. Perceived high risk in mothers, followed by personal risk, was most effective in eliminating size-dependent behavior whereas effects of paternal risk on offspring behavioral development were substantially weaker. When maternal risk is high, environmental mismatches between parents prevented offspring from responding appropriately to personal high risk. The environment of the caring male also impacted offspring behavior to a greater extent than that of its genetic parents. Our study highlights the high relative importance of maternal, personal and caring male risk environments and showcases potential costs of an environmental mismatch between parental sexes.

Optimizing anidulafungin exposure across a wide adult body size range.

Echinocandins like anidulafungin are first-line therapies for candidemia and invasive candidiasis, but their dosing may be suboptimal in obese patients. Our objective was to quantify anidulafungin exposure in a cohort of adults across a wide body size range to test if body size affects anidulafungin pharmacokinetics (PK). We enrolled 20 adults between the ages of 18 and 80 years, with an equal distribution of patients above and below a body mass index of 30 kg/m2. A single 100-mg dose of anidulafungin was administered, followed by intensive sampling over 72 h. Population PK analysis was used to identify and compare covariates of anidulafungin PK parameters. Monte Carlo simulations were performed to compute the probability of target attainment (PTA) based on alternative dosing regimens. Participants (45% males) had a median (range) age of 45 (21-78) years and a median (range) weight of 82.7 (42.4-208.3) kg. The observed median (range) of AUC0-∞ was 106.4 (51.9, 138.4) mg∙h/L. Lean body weight (LBW) and adjusted body weight (AdjBW) were more influential than weight as covariates of anidulafungin PK parameters. The conventional 100 mg daily maintenance is predicted to have a PTA below 90% in adults with an LBW > 55 kg or an AdjBW > 75 kg. A daily maintenance dose of 150-200 mg is predicted in these heavier adults. Anidulafungin AUC0-∞ declines with increasing body size. A higher maintenance dose will increase the PTA compared to the current approach in obese patients.

Energetic costs of feeding in 12 species of small-bodied primates.

There are no comparative, empirical studies of the energetic costs of feeding in mammals. As a result, we lack physiological data to better understand the selection pressures on the mammalian feeding apparatus and the influence of variables such as food geometric and material properties. This study investigates interspecific scaling of the net energetic costs of feeding in relation to body size, jaw-adductor muscle mass and food properties in a sample of 12 non-human primate species ranging in size from 0.08 to 4.2 kg. Net energetic costs during feeding were measured by indirect calorimetry for a variety of pre-cut and whole raw foods varying in geometric and material properties. Net feeding costs were determined in two ways: by subtracting either the initial metabolic rate prior to feeding or subtracting the postprandial metabolic rate. Interspecific scaling relationships were evaluated using pGLS and OLS regression. Net feeding costs scale negatively relative to both body mass and jaw-adductor mass. Large animals incur relatively lower feeding costs indicating that small and large animals experience and solve mechanical challenges in relation to energetics in different ways. This article is part of the theme issue 'Food processing and nutritional assimilation in animals'.

How Should We Approach Body Size Diversity in Clinical Trials?

Regulatory and ethical considerations mandate that minorities affected by health disparities be included in research. Despite concerns about clinical outcomes for patients with obesity, clinical trials have reported few data about participation of and outcomes for such patients. This article examines the lack of body size diversity in clinical research participants and reviews the evidence and ethical arguments for including larger-bodied patients. Drawing on examples of improved gender diversification of trial participants, this article suggests that similar benefits would be likely from inclusion of body diversity.

Energy expenditure of southern right whales varies with body size, reproductive state and activity level.

Quantifying the energy expenditure of animals is critical to understanding the cost of anthropogenic disturbance relative to their overall energy requirements. We used novel drone focal follows (776 follows, 185 individuals) and aerial photogrammetry (5372 measurements, 791 individuals) to measure the respiration rate and body condition loss of southern right whales (Eubalaena australis) on a breeding ground in Australia. Respiration rates were converted to oxygen consumption rate and field metabolic rate (FMR) using published bioenergetic models. The intra-seasonal loss in body condition of different reproductive classes (calves, juveniles, adults, pregnant and lactating females) was converted to blubber energy loss and total energy expenditure (TEE). Using these two metrics, we tested the effects of body size, reproductive state and activity level on right whale energy expenditure. Respiration rates and mass-specific FMR decreased exponentially with an increase in body size, as expected based on allometric scaling. FMR increased curvilinearly with an increase in swim speed, probably as a result of increased drag and increased locomotion costs. Respiration rates and FMR were 44% higher for pregnant and lactating females compared with those of adults, suggesting significant costs of fetal maintenance and milk production, respectively. The estimated FMR of adults based on their respiration rates corresponded well with the estimated TEE based on body condition loss. The rate of decline in body condition of pregnant and lactating females was considerably higher than expected based on respiration rates, which probably reflects the milk energy transfer from mothers to calves, which is not reflected in their FMR.

An Investigation of Body Size Impact on Organ Doses for Neutron External Exposures Using the MRCP-based Phantom Library.

ABSTRACT: In a recent study, a comprehensive library composed of 212 phantoms with different body sizes was established by deforming the adult male and female mesh-type reference computational phantoms (MRCPs) of ICRP Publication 145 and the next-generation ICRP reference phantoms over the current voxel-type reference phantoms of ICRP Publication 110. In this study, as an application of the MRCP-based phantom library, we investigated dosimetric impacts due to the different body sizes for neutron external exposures. A comprehensive dataset of organ/tissue dose coefficients (DCs) for idealized external neutron beams with four phantoms for each sex representatively selected from the phantom library were produced by performing Monte Carlo simulations using the Geant4 code. The body size-dependent DCs produced in this study were systematically analyzed, observing that the variation of the body weights overall played a more important role in organ/tissue dose calculations than the variation of the body heights. We also observed that the reference body-size DCs based on the MRCPs indeed significantly under- or overestimated the DCs produced using the phantoms, especially for those much heavier (male: 175 cm and 140 kg; female: 165 cm and 140 kg) than the reference body sizes (male: 176 cm and 73 kg; female: 163 cm and 60 kg) by up to 1.6 or 3.3 times, respectively. We believe that the use of the body size-dependent DCs, together with the reference body-size DCs, should be beneficial for more reliable organ/tissue dose estimates of individuals considering their body sizes rather than the most common conventional approach, i.e., the sole use of the reference body size DCs.

TimeFISH: Long-term assessment of reef fish assemblages in a transition zone in the Southwestern Atlantic.

The TimeFISH database provides the first public time-series dataset on reef fish assemblages in the southwestern Atlantic (SWA), comprising 15 years of data (2007-2022) based on standardized Underwater Visual Censuses (UVCs). The rocky reefs covered by our dataset are influenced by pronounced seasonal cycles of ocean temperatures with warm tropical waters from the Brazil Current in the summer (~27°C) and colder waters from the La Plata River Plume discharge and upwelling from the South Atlantic Central Water in the winter (~18°C). These oceanographic conditions characterize this area as the southernmost tropical-subtropical climatic transition zone in the Atlantic Ocean. As a result, reef fish assemblages are comprised of both tropical and subtropical species. All records included in TimeFISH were collected using UVCs, a nondestructive method that allows the estimation of fish species richness, abundance, and body size distributions. UVCs were performed through 40 m2 belt transects by scuba diving in nine locations along the southern Brazilian coast (25-29°S). Four of these locations lie within the boundaries of the no-entry Arvoredo Marine Biological Reserve, where fishing and recreational activities are forbidden, and the remaining locations are unprotected from these activities. During each belt transect, a diver swam at a constant depth above and parallel to the reef, identifying fish species, counting the number of individuals, and estimating the total body length (Lt in cm) of all detected individuals. All fish individuals in the water column (up to 2 m above the substratum) and at the bottom were targeted. In total, 202,965 individuals belonging to 163 reef fish species and 53 families were recorded across 1857 UVCs. All survey campaigns were funded by either public or mixed capital (private-public) sources, including seven grants from the Brazilian federal and Santa Catarina state governments. Part of the data has already been used in multiple MS.c. and Ph.D. theses and scientific articles. TimeFISH represents an important contribution for future studies aiming to examine temporal and spatial variations of reef fish assemblages in transition zones. No copyright restrictions apply to the use of this data set, other than citing this publication.

A body-size-dependent series of Chinese adult standing phantoms for radiation dosimetry.

Phantoms of different sizes, as indicated by several studies, have a significant impact on the accuracy of dose calculations. Therefore, it is necessary to establish a body-size-dependent series of Chinese standing adult phantoms to improve the accuracy of radiation dosimetry. In this study, the Chinese reference polygon-mesh phantomsCRAM_S/CRAF_Shave been refined and a method for automatically constructing lymph nodes in a mesh phantom has been proposed. Then, based on the refined phantoms, this study has developed 42 anthropometric standing adult computational phantoms, 21 models for each gender, with a height range of 145-185 cm and weight as a function of body mass index corresponding to healthy, overweight and obese. The parameters were extracted from the National Occupational Health Standards (GBZ) document of the People's Republic of China, which covers more than 90% of the Chinese population. For a given body height and mass, phantoms are scaled in proportion to a factor reflecting the change of adipose tissue and the internal organs. The remainder is adjusted manually to match the target parameters. In addition, the constructed body-size-specific phantoms have been implemented in the in-house THUDose Monte Carlo code to calculate the dose coefficients (DCs) for external photon exposures in the antero-posterior, postero-anterior and right lateral geometries. The results showed that organ DCs varied significantly with body size at low energies (<2MeV) and high energies (>8MeV) due to the differences in anatomy. Organ DC differences between a phantom of a given size and a reference phantom vary by up to 40% for the same height and up to 400% for the whole phantom. The influence of body size differences on the DCs demonstrates that the body-size-dependent Chinese adult phantoms hold great promise for a wide range of applications in radiation dosimetry.

The effect of different socio-economic and working conditions on body size and proportions: A case study on adults from Samsun, Turkey.

Conditions in the early stages of life shape body size and proportions. This study includes individuals who came from different socio-economic conditions and worked in physically demanding jobs in childhood. By determining the body sizes of these individuals and evaluating the proportional relationships between several groups, the goal was to understand the effect levels of socio-economic levels and working conditions on the body. For this purpose, an anthropometric study was conducted on 623 males and females between the ages of 20 and 45 living in Samsun, Turkey. The study sample consisted of four different groups. It was divided into two main groups of high and low socio-economic level, and the low socio-economic group was divided into two subgroups of heavy-worker and nonheavy-worker. The results demonstrated that socio-economic differences in the size and proportions of the individuals were statistically significant (p<0.05). The high socio-economic group had the highest values in all measures. External factors affected the lower limbs more than the upper limbs. The measurement most affected by these factors was leg length. Longer legs characterized the high socio-economic group, while longer arms characterized both low socio-economic groups. The relative differences observed can be said to derive from the distal limbs. This finding was valid for both sexes. The average values were close to each other in the low socio-economic group, for which the aim was to comprehend the effects of heavy working conditions. However, differences in proportional relationships were more significant. In this context, it was seen that heavy labour also affected growth, in addition to the well-known factors encountered during the growth period, such as nutrition, health, and illness. The observed changes were more significant in males than in females. Thus, it can be said that males were more affected by physiological and physical conditions.

The growth curve determination and economic trait correlation for Qinchuan bull population.

Carcass weight, as a measure of meat yield, and body measurements are directly correlated traits in livestock. However, longitudinally collected phenotype records of local breeds are not comprehensive. The research was performed on Qinchuan bull population to understand their growth and development, and data from Qinchuan bull that was weighed and measured at birth, 6, 12, 18, and 24 months of age was analyzed. Furthermore, Logistic, Brody, Gompertz, and Bertallanffy were used to fit the growth curves for weight and body size traits. The results showed that the four curve models have good fitting degrees for the weight and body size (R2 > 0.99), and the Bertallanffy model exhibited a good fit to the measured data of body weight, and the model estimated the inflection point of body weight as (5.43 months of age, 122.01 kg). Particularly, the limited mature body weight can reach 557.8 kg by the Brody model. Body weight was significantly positively correlated with body height, hip height, body length, chest circumference, abdominal girth, and calf girth (p < 0.0001), and the correlation between body weight and body length was the highest (r = 0.975). The regression equation predicting body weight was Y = -275.691 + 3.28 X3 + 1.311 X4 - 0.397 X5.

Assessment of Body Frame Size by Elbow Breadth and Frame Index and Its Relation to Body Composition Parameters among Tribal Preschool Children in West Bengal, India.

SUMMARY: In children, body frame size estimation is used to interpret body mass and evaluate growth patterns. The present study aims to assess the body frame size by elbow breadth and frame index and its relation to body composition parameters among tribal preschool children (1-5 years of age). In the present study, 848 preschool children (430 boys and 418 girls) were included. The mean elbow breadth showed an increasing trend with increasing age, but inverse results were observed in the case of frame index. Age-wise, statistically significant sex differences were found in mean elbow breadth and frame index (except for 2 years of age). Boys show higher mean elbow breadth and frame index in all age groups, and significant sex differences were found. Elbow breadth and frame index had the strongest significant positive correlations with fat free mass (FFM) (r = 0.590, P < 0.01) and FFM index (r = 0.539, P < 0.01), respectively.

Ecological Drivers and Consequences of Bumble Bee Body Size Variation.

Body size is arguably one of the most important traits influencing the physiology and ecology of animals. Shifts in animal body size have been observed in response to climate change, including in bumble bees (Bombus spp. [Hymenoptera: Apidae]). Bumble bee size shifts have occurred concurrently with the precipitous population declines of several species, which appear to be related, in part, to their size. Body size variation is central to the ecology of bumble bees, from their social organization to the pollination services they provide to plants. If bumble bee size is shifted or constrained, there may be consequences for the pollination services they provide and for our ability to predict their responses to global change. Yet, there are still many aspects of the breadth and role of bumble bee body size variation that require more study. To this end, we review the current evidence of the ecological drivers of size variation in bumble bees and the consequences of that variation on bumble bee fitness, foraging, and species interactions. In total we review: (1) the proximate determinants and physiological consequences of size variation in bumble bees; (2) the environmental drivers and ecological consequences of size variation; and (3) synthesize our understanding of size variation in predicting how bumble bees will respond to future changes in climate and land use. As global change intensifies, a better understanding of the factors influencing the size distributions of bumble bees, and the consequences of those distributions, will allow us to better predict future responses of these pollinators.

Baboon perspectives on the ecology and behavior of early human ancestors.

For more than 70 y researchers have looked to baboons (monkeys of the genus Papio) as a source of hypotheses about the ecology and behavior of early hominins (early human ancestors and their close relatives). This approach has undergone a resurgence in the last decade as a result of rapidly increasing knowledge from experimental and field studies of baboons and from archeological and paleontological studies of hominins. The result is a rich array of analogies, scenarios, and other stimuli to thought about the ecology and behavior of early hominins. The main intent here is to illustrate baboon perspectives on early hominins, with emphasis on recent developments. This begins with a discussion of baboons and hominins as we know them currently and explains the reasons for drawing comparisons between them. These include occupation of diverse environments, combination of arboreal and terrestrial capabilities, relatively large body size, and sexual dimorphism. The remainder of the paper illustrates the main points with a small number of examples drawn from diverse areas of interest: diet (grasses and fish), danger (leopards and crocodiles), social organization (troops and multilevel societies), social relationships (male-male, male-female, female-female), communication (possible foundations of language), cognition (use of social information, comparison of self to others), and bipedalism (a speculative developmental hypothesis about the neurological basis). The conclusion is optimistic about the future of baboon perspectives on early hominins.