Development of a three-dimensional body shape model of young children for child restraint design

Abstract

The design of child restraints is guided in part by anthropometric data describing the distributions of body dimensions of children. However, three-dimensional body shape data have not been available for children younger than three years of age. This study presents body shape models for children weighing 9–23?kg in a seated posture relevant to child restraint design. A laboratory study collected surface geometry data of 67 children, ages 12–58 months. Novel template fitting methods were employed to obtain homologous meshes and to standardize the posture. Principal component analysis and regression were used to develop a statistical body shape model (SBSM). The SBSM was exercised to create 18 manikins representing children aged 1–3 years, with varying size and shape. These manikins will be useful for assessing child accommodation in restraints. The SBSM can also provide guidance for the development of anthropomorphic test devices and computational models of child occupants.     

Head proportion and shape of the head of children between 2 and 7 years--results of a longitudinal study

Based upon a longitudinal anthropometric study with integrated picture documentation, the head proportion and head shape of two to seven years old children will be analysed. The study was initiated in April 2002 in the administrative districts of Potsdam and Potsdam-Mittelmark (Germany). 351 boys and girls have been measured and photographed. The children shall be examined up to four years until September 2006 with a half year investigation distance. Twenty-three anthropometric dimensions have been measured including six dimensions of the head. These dimensions of the head are the head length, head breadth, auricular height, interpupillary distance, facial height and lower face height. Furthermore, digital pictures have been taken of each child. So the head of each child can be examined in a frontal view (Norma frontalis) and in a lateral view (Norma lateralis) and will be analysed relating to changing proportions of the head. The results demonstrated and discussed here are based on a longitudinal succession of photos and point out a method to make individual patterns of the changing head proportions and head shape visual on pictures.     

Parents’ education and child body weight in France: The trajectory of the gradient in the early years

This paper explores the relationship between parental education and offspring body weight in France. Using two large datasets spanning the 1991–2010 period, we examine the existence of inequalities in maternal and paternal education and reported child body weight measures, as well as their evolution across childhood. Our empirical specification is flexible and allows this evolution to be non-monotonic. Significant inequalities are observed for both parents’ education – maternal (respectively paternal) high education is associated with a 7.20 (resp. 7.10) percentage points decrease in the probability that the child is reported to be overweight or obese, on average for children of all ages. The gradient with respect to parents’ education follows an inverted U-shape across childhood, meaning that the association between parental education and child body weight widens from birth to age 8, and narrows afterward. Specifically, maternal high education is correlated with a 5.30 percentage points decrease in the probability that the child is reported to be overweight or obese at age 2, but a 9.62 percentage points decrease at age 8, and a 1.25 percentage point decrease at age 17. The figures for paternal high education are respectively 5.87, 9.11, and 4.52. This pattern seems robust, since it is found in the two datasets, when alternative variables for parental education and reported child body weight are employed, and when controls for potential confounding factors are included. The findings for the trajectory of the income gradient corroborate those of the education gradient. The results may be explained by an equalization in actual body weight across socioeconomic groups during youth, or by changes in reporting styles of height and weight.     

Morphometric analysis of variation in the sternum with sex and age

Age and sex‐related variations in sternum morphology may affect the thoracic injury tolerance. Male and female sternum size and shape variation was characterized for ages 0–100 from landmarks collected from 330 computed tomography scans. Homologous landmarks were analyzed using Procrustes superimposition to produce age and sex‐specific functions of 3D‐sternum morphology representing the combined size and shape variation and the isolated shape variation. Significant changes in the combined size and shape variation and isolated shape variation of the sternum were found to occur with age in both sexes. Sternal size increased from birth through age 30 and retained a similar size for ages 30–100. The manubrium expanded laterally from birth through age 30, becoming wider in relation to the sternal body. In infancy, the manubrium was 1.1–1.2 times the width of the sternal body and this width ratio increased to 1.6–1.8 for adults. The manubrium transformed from a circular shape in infancy to an oval shape in early childhood. The distal sternal body became wider in relation to the proximal sternal body from birth through age 30 and retained this characteristic throughout adulthood. The most dramatic changes in sternum morphology occur in childhood and young adulthood when the sternum is undergoing ossification. The lesser degree of ossification in the pediatric sternum may be partly responsible for the prevalence of thoracic organ injuries as opposed to thoracic skeletal injuries in pediatrics. Sternum fractures make up a larger portion of thoracic injury patterns in adults with fully ossified sternums. The lack of substantial size or shape changes in the sternum from age 30–100 suggests that the increased incidence of sternal fracture seen in the elderly may be due to cortical thickness or bone mineral density changes in the sternum as opposed to morphological changes. J. Morphol. 275:1284–1299, 2014. © 2014 Wiley Periodicals, Inc.     

Sexual maturity and shape development in cranial appendages of extant ruminants

Morphological disparity arises through changes in the ontogeny of structures; however, a major challenge of studying the effect of development on shape is the difficulty of collecting time series of data for large numbers of taxa. A proxy for developmental series proposed here is the age at sexual maturity, a developmental milestone potentially tied to the development of structures with documented use in intrasexual competition, such as cranial appendages in Artiodactyla. This study tested the hypothesis that ruminant cranial appendage shape and size correlate with onset of sexual maturity, predicting that late sexual maturity would correlate with larger, more complicated cranial appendages. Published data for cranial appendage shape and size in extant taxa were tested for correlations with sexual maturity using linear mixed‐effect models and phylogenetic generalized least‐squares analyses. Ancestral state reconstructions were used to assess correlated variables for developmental shifts indicative of heterochrony. These tests showed that phylogeny and body mass were the most common predictors of cranial appendage shape and sexual maturity was only significant as an interaction with body mass. Nevertheless, using developmental milestones as proxies for ontogeny may still be valuable in targeting future research to better understand the role of development in the evolution of disparate morphology when correlations exist between the milestone and shape.     

Age-variability in body shape associated with excess weight: the UK National Sizing Survey

Background: The health risks of obesity are disproportionately due to central abdominal adiposity; however, the extent to which age is associated with the body shape of obese adults is not known. Objective: Three‐dimensional (3D) data on body shape from the UK National Sizing Survey were analyzed to investigate age‐associated changes in body shape within the BMI bands <20, 20–24.99, 25–29.99 and ≥30 kg/m². Methods: Measurements of anthropometry (weight and height) and a 3D body scan were obtained in 4,344 men and 5,266 women recruited from eight British cities. Results: The body shape of men showed high consistency within BMI bands between early adulthood and old age. In contrast, the body shape of women altered within each BMI band with increasing age. In obese, overweight, and normal weight women, age was associated with decreased thigh girth, increased waist, and bust girth. Whereas young obese women maintained an hourglass shape, in old age the body shape of obese women converged on that of obese men. Discussion: The association of age with body shape is markedly different between the sexes, with the impact of obesity on shape strongly age‐dependent in women but not in men. The age delay in the association between obesity and high waist girth in women may contribute to the sex‐difference in life expectancy. The relationship between body shape change and cardiovascular risk merits longitudinal investigation within individuals.     

A multivariate study of three body measurements of different states of India

Considerable attempts have been made to study the changes in three important body measurements (viz. body height, body weight and chest circumference) in young healthy males between different states of India using univariate statistical analysis in which body measurements are assumed to be independent of each other. Actually these body measurements are correlated with each other and thus the assumption of independence is violated in univariate statistical analysis. Hence the results obtained by univariate statistical analysis may be misleading. An attempt has, therefore, been made in the present study to apply multivariate statistical analysis in order to have an idea about the simultaneous changes in these three correlated measurements between different states of India in healthy Indian males of age ranging from 16-21 years. It has been concluded that significant changes take place in these three body measurements simultaneously of young healthy males of 16-21 years of age between different states of India.     

Seasonal and developmental changes of reproductive organs of male ringed seals (Phoca hispida) in the Svalbard area

The weights of testes, prostate gland and baculum of ringed seal males were related to age, season and differences in body size. There was a significant seasonal variation in testes and prostate gland size of sexually mature males, with a maximum occurring in early April. There were no seasonal changes in prostate weight of immature males, but some of the older immatures had elevated testes weights in April. Testes weight was significantly correlated with lean body mass. The increase in testes size with increasing body weight was greater for seals six years of age or older than for younger males. We suggest that some testicular growth and a seasonal cycle in testes growth occur before the testes become functional endocrinologically. We also believe that the primary event leading to puberty in ringed seals is an age-dependent shift in metabolic processes, directing a larger percentage of available energy towards the reproductive organs.     

Ability of Young Women to Recall Past Body Size and Age at Menarche

Objective: The ability of young women (n = 132, average age 17 years) to recall body size and age at menarche was examined. The use of body silhouettes to assist women in recalling their body size at menarche and to represent their current body size was also evaluated. Research Methods and Procedures: Subjects, who previously participated in a cohort study, were asked to recall height and weight at the time of menarche, to select body silhouettes that best reflected their body shape at the time of menarche and their current body shape, and to recall age at menarche. Two sets of body silhouettes were developed, one representative of an adult body shape and another representative of an adolescent body shape. Results: Pearson correlation coefficients between the adult and adolescent body figures and actual body mass index (BMI; kg/m²) at the time of menarche were not significantly different (r = 0.82 for adult figures vs. r = 0.72 for adolescent figures, p > 0.05). The correlation between actual BMI at the time of menarche and body silhouette (r = 0.77, all subjects) was similar to the correlation between actual and recalled BMI at the time of menarche (r = 0.83) as well as the correlation between current BMI and current body silhouette (r = 0.75). Recalled and actual ages at menarche were highly correlated (r = 0.83). Discussion: The recall of body shape was considered to be a less precise measure of body size than asking about height and weight, but use of body silhouettes may offer advantages in certain situations.     

Phenotypic plasticity and contemporary evolution in introduced populations: evidence from translocated populations of white sands pupfish (<Emphasis Type="Italic">Cyrpinodon tularosa</Emphasis>)

Contemporary evolution has been shown in a few studies to be an important component of colonization ability, but seldom have researchers considered whether phenotypic plasticity facilitates directional evolution from the invasion event. In the current study, we evaluated body shape divergence of the New Mexico State-threatened White Sands pupfish (Cyprinodon tularosa) that were introduced to brackish, lacustrine habitats at two different time in the recent past (approximately 30 years and 1 year previously) from the same source population (saline river environment). Pupfish body shape is correlated with environmental salinity: fish from saline habitats are characterized by slender body shapes, whereas fish from fresher, yet brackish springs are deep-bodied. In this study, lacustrine populations consisted of an approximately 30-year old population and several 1-year old populations, all introduced from the same source. The body shape divergence of the 30-year old population was significant and greater than any of the divergences of the 1-year old populations (which were for the most part not significant). Nonetheless, all body shape changes exhibited body deepening in less saline environments. We conclude that phenotypic plasticity potentially facilitates directional evolution of body deepening for introduced pupfish populations.     

The interaction between predation risk and food ration on behavior and morphology of Eurasian perch

The risk of both predation and food level has been shown to affect phenotypic development of organisms. However, these two factors also influence animal behavior that in turn may influence phenotypic development. Hence, it might be difficult to disentangle the behavioral effect from the predator or resource‐level effects. This is because the presence of predators and high resource levels usually results in a lower activity, which in turn affects energy expenditure that is used for development and growth. It is therefore necessary to study how behavior interacts with changes in body shape with regard to resource density and predators. Here, we use the classic predator‐induced morphological defense in fish to study the interaction between predator cues, resource availability, and behavioral activity with the aim to determine their relative contribution to changes in body shape. We show that all three variables, the presence of a predator, food level, and activity, both additively and interactively, affected the body shape of perch. In general, the presence of predators, lower swimming activity, and higher food levels induced a deep body shape, with predation and behavior having similar effect and food treatment the smallest effect. The shape changes seemed to be mediated by changes in growth rate as body condition showed a similar effect as shape with regard to food‐level and predator treatments. Our results suggests that shape changes in animals to one environmental factor, for example, predation risk, can be context dependent, and depend on food levels or behavioral responses. Theoretical and empirical studies should further explore how this context dependence affects fitness components such as resource gain and mortality and their implications for population dynamics.     

Shape recognition and image orientation in young children]

A comparison was made of recognition of images in the direct and inverse "top-bottom" orientation. A child two and a half years old was to find the test image on the response card or to give a verbal reply. The verbal responses have shown that the child identifies well both the shape and orientation of the images. In experiments with the response card, the presentation of images in inverse orientation did not result in any mistakes in recognizing the shape nor did it prolong the latency of the reaction, and no correlation was found between the orientation of the presented and the response figures. A child trained to find images of both similar shape and orientation is incapable of indicating properly the orientation of an image presented for a limited time period. These facts are interpreted in terms of the hypothesis of multichannel transfer of information about the pattern in the visual system.     

Normal N-acetylglutamate concentration measured in liver from a new patient with N-acetylglutamate synthetase deficiency: physiologic and biochemical implications.

N-Acetyl-L-glutamate synthetase (NAG synthetase) is a mitochondrial matrix enzyme which catalyzes the synthesis of N-acetyl-Lglutamate (NAG), a physiologic activator of the urea cycle enzyme carbamylphosphate synthetase I. Deficiency of NAG synthetase in humans has been reported only three times previously. Two cases presented with uncontrolable neonatal hyperammonemia leading to death, while a third child presented with hyperammonemia and a neurodegenerative picture at 15 months of age after previously being healthy. We report here a new case of NAG synthetase deficiency who presented at 4 years, 10 months of age with an episode of hyperammonemia. Diagnosis was made at age 5 years, 6 months when a liver biopsy showed 9.7% of normal activity. Urine orotic acid was low, and total NAG content in liver was normal. Liver pathology revealed micro- and macrovesicular fat and mitochondria of irregular size and shape with intracristae crystallizations. NAG content in liver in patients with NAG synthetase deficiency has not previously been reported. Its normal value in the face of NAG synthetase deficiency suggests an abnormal localization of NAG to the cytoplasm and the likelihood of aberrant cytoplasmic synthesis of this compound. Additional physiologic implications of this speculative abnormal compartmentalization are discussed.     

The origins of allometry: size and shape polymorphism in the common waterstrider, Gerris remigis Say (Heteroptera, Gerridae)

Changes in size, whether ontogenetic or phylogenetic, tend to be associated with changes in shape. This allometry can arise through two different evolutionary mechanisms: (1) selection acting primarily on overall size may be associated with changes in shape because of physiological and mechanical constraints or differential responses of different body components; or (2) selection acting primarily on shape (on the size of specific body components) may be associated with changes in overall size because of genetic correlations, and thus correlated responses, of other body components. To assess the relative importance of these two mechanisms, shape polymorphism is examined along two axes of size dimorphism (sex and wing morphology) in the common waterstrider, Gerris remigis Say. Eight measurements were made of body and appendage components of 234 adults, from three independent populations. Univariate and multivariate analyses reveal that both sexes and wing morphs differ significantly in size and shape. Shape differentiation along the two axes of size dimorphism is found to be dissimilar, partially independent of size, and strongly correlated with the ecological specialization of the various morphs. These observations suggest that selection is acting directly on shape, and thus that allometry in this species primarily reflects shape-mediated changes in size (mechanism 2), rather than size-mediated changes in shape. The role of developmental processes in facilitating this shape differentiation is discussed.     

Fat body involvement in vitellogenin fate in the green frog, Rana esculenta

1. Since, in Rana esculenta, fat bodies contain vitellogenin, the present study was performed in order to determine whether or not fat bodies are involved in the fate of vitellogenin. 2. The experiment of November shows that fat body excision provokes plasma vitellogenin increase even in animals treated with estradion-17 beta + pituitary crude homogenate (as compared with relative control). The same picture has been shown in the April experiment. 3. The result on protein-bound phosphate in ovaries from the April experiment has shown that fat body extirpation causes a decrease of protein-bound phosphate in the ovary. 4. This results indicates that fat bodies play an important role in sequestrating circulating vitellogenin by the ovary.     

Plasticity of fish body shape. The effects of diet, development, family and age in two species of Geophagus (Pisces: Gichlidae)

Fish body shape is affected by the genetic makeup of an individual as well as environmental influences, such as diet, development, growth rate and nutrition. Fishes in the family Cichlidae exhibit tremendous morphological diversity in body shape and morphology related to feeding. Certain aspects of cichlid feeding morphology have been shown to be plastic in response to different diets but plasticity in body shape has not been examined previously. Plasticity affects ecological interactions, the direction and rate of evolution, and has ramifications for characters used in systematic studies. I examined the effect of different diets: chironomid larvae (bloodworms) and brine shrimp nauplii, on body shape in two species of the Neotropical cichlid genus Geophagus which differ in the size at which young begin feeding on external food sources. The fry of G. brasiliensis , a substrate spawner, begin to feed on external food sources earlier than the fry of G. steindachneri , a mouthbrooder. I hypothesized that the difference in size at first feeding could lead to a difference in the amount of plasticity inducible in the two species. The magnitudes of changes were mostly similar, although G. brasiliensis responded to the different diets with slightly greater changes in some of the head measurements. The pattern of changes in the two species were also similar, with fish fed ferine shrimp nauplii developing longer and shallower heads and shallower bodies and tails than fish fed chironomid larvae. I also examined the consequences of considering family and age as additional factors besides diet in G. steindachneri. Considering family or age as additional factors in the analyses did not change the conclusion that different diets induce differences, albeit small ones, in body shape. I argue that morphological plasticity is dependent on behavioural flexibility and that it may enhance evolutionary morphological diversification.     

中国蒙古族体型特征

采用Heath-Carter体型法研究了中国蒙古族14个族群4810例（男性2117例,女性2693例）的体型。蒙古族内因子、中因子与年龄呈显著正相关,外因子与年龄呈显著负相关,即随年龄增长,身体线性度变小,体型趋于圆粗。蒙古族男性、女性体型都集中于偏内胚层的中胚层体型、内胚层-中胚层均衡体型、偏中胚层的内胚层体型。随着年龄增长,这3种体型的出现率均与年龄呈显著正相关,即蒙古族体型有向这3种体型集中的趋势。和汉族人相比,蒙古族身体更粗壮。主成分分析结果显示,东北三省蒙古族身体线性度小,体脂发达,骨骼和肌肉量较少。在体型图上北方蒙古族的点分布密集,说明北方蒙古族彼此体型比较接近,而南方的云南蒙古族由于内因子值小、外因子大,位点与北方蒙古族相距较远。在已经开展Heath-Carter体型法研究的中国族群中,蒙古族是体脂最为发达、身体线性度很小的民族。     

Life-history strategies of Acrossocheilus fasciatus (Barbinae, Cyprinidae) in the Huishui Stream of the Qingyi watershed, China

Life-history traits of Acrossocheilus fasciatus were examined using 384 specimens collected monthly during May 2009 and April 2010 in the Huishui Stream of the Qingyi watershed, China. Using scales for age determination, female and male fish comprised five and four age groups, respectively. The monthly changes in marginal increment ratio suggested that annuli on scales were formed during March through May. Total lengths back-calculated significantly increased with age for both sexes and varied significantly between the two sexes at each age. The fact that females had larger body size and grew faster than males indicated the sexual size dimorphism for this species. Both sexes got their 50% maturity at age 3, when females and males were 105.3 and 112.1?mm total length, respectively. Based on the monthly changes in the gonado-somatic index and egg-development process, fish spawned from April through August. Absolute fecundity ranged from 295 to 3,573 eggs per fish and increased significantly with age. But relative fecundity, ranging from 11.77 to 69.96?eggs/g, was not significantly different among age groups. Compared with the life-history traits of an upstream population in the Puxi Stream (a headwater stream within this study watershed), the downstream population of A. fasciatus in the Huishui Stream (a 4th-order stream) exhibits larger body size, faster somatic growth, later sexual maturity, and lower reproductive investment. These variations in life-history strategies between the two populations could perhaps be explained by the spatial heterogeneity in habitat environment along the upstream–downstream gradient in this watershed.     

Evolution of the immune system in humans from infancy to old age

This article reviews the development of the immune response through neonatal, infant and adult life, including pregnancy, ending with the decline in old age. A picture emerges of a child born with an immature, innate and adaptive immune system, which matures and acquires memory as he or she grows. It then goes into decline in old age. These changes are considered alongside the risks of different types of infection, autoimmune disease and malignancy.     

The relationship between median nerve somatosensory evoked potential latencies and age and growth parameters in young children

Median nerve somatosensory evoked potentials (SEPs) were recorded in a group of 35 normal children aged 6–36 months and related to body length, body weight and head circumference. Recordings were made while the child was awake using the following derivations: ipsilateral clavicle - Fpz; seventh cervical vertebra (CV7) - Fpz; contralateral C′ - Fpz. the clavicular-Fpz response was bilobed in 77% of the recordings, the initial being designated CL1 and the following negativity, CL2. Early negativities, coincident in latency with CL1 and CL2, were often present inin CV7-Fpz recordings, however, a negativity longer in latency than CL2 was always present, was designated CVN, and preceded a prominent positivity. A scalp-recorded early negativity (N1) and a following positivity (P1) were well defined in all recordings.The latency of CL1, CL2 and CVN increased with an increase in age and stature. In contrast, significant negative correlations were found between the latency of N1, P1, age and statur. The CL1-CVN interpeak latency did not correlate significantly with age, while the central conduction time (CVN-N1) declined with an increase in age and stature. These findings confirmed the complexity of SEP absolute and interpeak latency changes with an increase in age and stature in young children.