scholarly journals Lower rotational inertia and larger leg muscles indicate more rapid turns in tyrannosaurids than in other large theropods

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6432 ◽  
Author(s):  
Eric Snively ◽  
Haley O’Brien ◽  
Donald M. Henderson ◽  
Heinrich Mallison ◽  
Lara A. Surring ◽  
...  

Synopsis Tyrannosaurid dinosaurs had large preserved leg muscle attachments and low rotational inertia relative to their body mass, indicating that they could turn more quickly than other large theropods. Methods To compare turning capability in theropods, we regressed agility estimates against body mass, incorporating superellipse-based modeled mass, centers of mass, and rotational inertia (mass moment of inertia). Muscle force relative to body mass is a direct correlate of agility in humans, and torque gives potential angular acceleration. Agility scores therefore include rotational inertia values divided by proxies for (1) muscle force (ilium area and estimates of m. caudofemoralis longus cross-section), and (2) musculoskeletal torque. Phylogenetic ANCOVA (phylANCOVA) allow assessment of differences in agility between tyrannosaurids and non-tyrannosaurid theropods (accounting for both ontogeny and phylogeny). We applied conditional error probabilities a(p) to stringently test the null hypothesis of equal agility. Results Tyrannosaurids consistently have agility index magnitudes twice those of allosauroids and some other theropods of equivalent mass, turning the body with both legs planted or pivoting over a stance leg. PhylANCOVA demonstrates definitively greater agilities in tyrannosaurids, and phylogeny explains nearly all covariance. Mass property results are consistent with those of other studies based on skeletal mounts, and between different figure-based methods (our main mathematical slicing procedures, lofted 3D computer models, and simplified graphical double integration). Implications The capacity for relatively rapid turns in tyrannosaurids is ecologically intriguing in light of their monopolization of large (>400 kg), toothed dinosaurian predator niches in their habitats.

Author(s):  
Eric Snively ◽  
Haley O'Brien ◽  
Donald M Henderson ◽  
Heinrich Mallison ◽  
Lara A Surring ◽  
...  

Synopsis: Tyrannosaurid dinosaurs had larger than predicted preserved leg muscle attachments and low rotational inertia relative to their body mass, indicating that they could turn more quickly than other large theropods. Methods: To compare turning capability in theropods, we regressed agility estimates against body mass, incorporating superellipse-based modeled mass, centers of mass, and rotational inertia (mass moment of inertia). Muscle force relative to body mass is a direct correlate of agility in humans, and torque gives potential angular acceleration. Agility scores therefore include rotational inertia values divided by proxies for (1) muscle force (ilium area and estimates of m. caudofemoralis longus cross-section), and (2) musculoskeletal torque. Phylogenetic ANCOVA (phylANCOVA) allow assessment of differences in agility between tyrannosaurids and non-tyrannosaurid theropods (accounting for both ontogeny and phylogeny). We applied conditional error probabilities a(p) to stringently test the null hypothesis of equal agility. Results: Tyrannosaurids consistently have agility index magnitudes twice those of allosauroids and some other theropods of equivalent mass, turning the body with both legs planted or pivoting over a stance leg. PhylANCOVA demonstrates definitively greater agilities in tyrannosaurids, and phylogeny explains nearly all covariance. Mass property results are consistent with those of other studies based on skeletal mounts, and between different figure-based methods (our main mathematical slicing procedures, lofted 3D computer models, and simplified graphical double integration). Implications: The capacity for relatively rapid turns in tyrannosaurids is ecologically intriguing in light of their monopolization of large (>400 kg), toothed dinosaurian predator niches in their habitats.


2018 ◽  
Author(s):  
Eric Snively ◽  
Haley O'Brien ◽  
Donald M Henderson ◽  
Heinrich Mallison ◽  
Lara A Surring ◽  
...  

Synopsis: Tyrannosaurid dinosaurs had larger than predicted preserved leg muscle attachments and low rotational inertia relative to their body mass, indicating that they could turn more quickly than other large theropods. Methods: To compare turning capability in theropods, we regressed agility estimates against body mass, incorporating superellipse-based modeled mass, centers of mass, and rotational inertia (mass moment of inertia). Muscle force relative to body mass is a direct correlate of agility in humans, and torque gives potential angular acceleration. Agility scores therefore include rotational inertia values divided by proxies for (1) muscle force (ilium area and estimates of m. caudofemoralis longus cross-section), and (2) musculoskeletal torque. Phylogenetic ANCOVA (phylANCOVA) allow assessment of differences in agility between tyrannosaurids and non-tyrannosaurid theropods (accounting for both ontogeny and phylogeny). We applied conditional error probabilities a(p) to stringently test the null hypothesis of equal agility. Results: Tyrannosaurids consistently have agility index magnitudes twice those of allosauroids and some other theropods of equivalent mass, turning the body with both legs planted or pivoting over a stance leg. PhylANCOVA demonstrates definitively greater agilities in tyrannosaurids, and phylogeny explains nearly all covariance. Mass property results are consistent with those of other studies based on skeletal mounts, and between different figure-based methods (our main mathematical slicing procedures, lofted 3D computer models, and simplified graphical double integration). Implications: The capacity for relatively rapid turns in tyrannosaurids is ecologically intriguing in light of their monopolization of large (>400 kg), toothed dinosaurian predator niches in their habitats.


2007 ◽  
Vol 177 (4S) ◽  
pp. 64-64
Author(s):  
Murugesan Manoharan ◽  
Martha A. Reyes ◽  
Alan M. Nieder ◽  
Bruce R. Kava ◽  
MarkS Soloway

Author(s):  
K. Subramanyam ◽  
Dr. P. Subhash Babu

Obesity has become one of the major health issues in India. WHO defines obesity as “A condition with excessive fat accumulation in the body to the extent that the health and wellbeing are adversely affected”. Obesity results from a complex interaction of genetic, behavioral, environmental and socioeconomic factors causing an imbalance in energy production and expenditure. Peak expiratory flow rate is the maximum rate of airflow that can be generated during forced expiratory manoeuvre starting from total lung capacity. The simplicity of the method is its main advantage. It is measured by using a standard Wright Peak Flow Meter or mini Wright Meter. The aim of the study is to see the effect of body mass index on Peak Expiratory Flow Rate values in young adults. The place of a study was done tertiary health care centre, in India for the period of 6 months. Study was performed on 80 subjects age group 20 -30 years, categorised as normal weight BMI =18.5 -24.99 kg/m2 and overweight BMI =25-29.99 kg/m2. There were 40 normal weight BMI (Group A) and 40 over weight BMI (Group B). BMI affects PEFR. Increase in BMI decreases PEFR. Early identification of risk individuals prior to the onset of disease is imperative in our developing country. Keywords: BMI, PEFR.


Physiotherapy ◽  
2013 ◽  
Vol 21 (3) ◽  
Author(s):  
Marzena Ślężyńska ◽  
Grzegorz Mięsok ◽  
Kamila Mięsok

AbstractIntroduction: The aim of the physical activity of the intellectually disabled is the strengthening of health, creating movement habits, promoting active recreation, and maintaining exercise capacity. Skillfully applied physical activity allows to mitigate the effects of pathology and create the compensations to enable the intellectually disabled people to live relatively independently. Physical activity and sport also increase their chances to integrate with their families, peers, and social environment.Materials and methods: The research targeted a group of 134 people with moderate or considerable intellectual disability (65 women and 69 men), aged 20-53 years, who participated in occupational therapy workshops in Jastrzębie Zdrój, Rybnik, and Żory. Physical fitness was assessed using the “Eurofit Special” test and balance tests. Measurements of body height and mass were also taken and then used to calculate the body mass index (BMI).Results: A salient somatic trait was the greater body mass relative to height among the persons with considerable disability, clearly illustrated by the BMI. This explained their greater heaviness in performing physical exercises. An even greater difference between participants with moderate and considerable intellectual disability was visible in physical fitness. Obviously, older persons did not achieve as good results in fitness tests as the younger ones, yet the participants were more differentiated by the level of disability than age. Most symptomatic differences to the disadvantage of the considerably disabled were observed in explosive strength, speed, abdominal muscle strength, and flexibility.Conclusions: Significant differences in fitness between the compared groups make it necessary to take into account the level of intellectual disability in the course of physical education and sport, at work, and in household duties.


2020 ◽  
Author(s):  
Valentina Cazzato ◽  
Elizabeth Walters ◽  
Cosimo Urgesi

We examined whether visual processing mechanisms of the body of conspecifics are different in women and men and whether these rely on westernised socio-cultural ideals and body image concerns. Twenty-four women and 24 men performed a visual discrimination task of upright or inverted images of female or male bodies and faces (Experiment 1) and objects (Experiment 2). In Experiment 1, both groups of women and men showed comparable abilities in the discrimination of upright and inverted bodies and faces. However, the genders of the human stimuli yielded different effects on participants’ performance, so that male bodies and female faces appeared to be processed less configurally than female bodies and male faces, respectively. Interestingly, altered configural processing for male bodies was significantly predicted by participants’ Body Mass Index (BMI) and their level of internalization of muscularity. Our findings suggest that configural visual processing of bodies and faces in women and men may be linked to a selective attention to detail needed for discriminating salient physical (perhaps sexual) cues of conspecifics. Importantly, BMI and muscularity internalization of beauty ideals may also play a crucial role in this mechanism.


2020 ◽  
Vol 66 (1) ◽  
pp. 71-78
Author(s):  
Lev Bershteyn ◽  
Aleksandr Ivantsov ◽  
Aglaya Ievleva ◽  
A. Venina ◽  
I. Berlev

The aim of this study was to evaluate steroid receptors’ status of tumor tissue in different molecular biological types of endometrial cancer (EC), subdivided according to the current classification, and their colonization by lymphocytic and macrophage cells, taking into account body mass index of the patients. Materials and methods: Material from treatment-naive patients with EC (total n = 229) was included; the number of sick persons varied depending on the method used. The average age of patients was close to 60 years, and about 90% of them were postmenopausal. It was possible to divide the results of the work into two main subgroups: a) depending on the molecular biological type of the tumor (determined on the basis of genetic and immunohistochemical analysis), and b) depending on the value of the body mass index (BMI). The latter approach was used in patients with EC type demonstrating a defective mismatch repair of the incorrectly paired nucleotides (MMR-D) and with a type without characteristic molecular profile signs (WCMP), but was not applied (due to the smaller number of patients) in EC types with a POLE gene mutation or with expression of the oncoprotein p53. According to the data obtained, when comparing various types of EC, the lowest values of Allred ER and PR scores were revealed for POLE-mutant and p53 types, while the “triple-negative” variant of the tumor (ER-, PR-, HER2/neu-) was most common in POLE-mutant (45.5% of cases) and WCMP (19.4%) types of EC. The p53+ type of EC is characterized by inclination to the higher expression of the macrophage marker CD68 and lymphocytic Foxp3, as well as mRNA of PD-1 and SALL4. In addition to the said above, for WCMP type of EC is peculiar, on the contrary, a decrease in the expression of lymphocytic markers CD8 (protein) and PD-L1 (mRNA). When assessing the role of BMI, its value of >30.0 (characteristic for obesity) was combined with an inclination to the increase of HER-2/neu expression in the case of MMR-D EC type and to the decrease of HER-2 /neu, FOXp3 and ER expression in WCMP type. Conclusions: The accumulated information (mainly describing here hormonal sensitivity of the tumor tissue and its lymphocytic-macrophage infiltration) additionally confirms our earlier expressed opinion that the differences between women with EC are determined by both the affiliation of the neoplasm to one or another molecular biological type (subdivided according to the contemporary classification), as well as by body mass value and (very likely) the associated hormonal and metabolic attributes.


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