Adaptive and phylogenetic influences on musculoskeletal design in cercopithecine primates

2002 ◽  
Vol 205 (21) ◽  
pp. 3399-3412 ◽  
Author(s):  
J. D. Polk
Keyword(s):  
Body Mass ◽  
Three Dimensional ◽  
Bending Moments ◽  
Joint Moments ◽  
Entire Sample ◽  
Mechanical Advantage ◽  
Similar Body ◽  
Walking Speeds ◽  
Locomotor Adaptations ◽  
Limb Proportions

SUMMARY Broad allometric studies of the musculoskeletal system have frequently sought to explain how locomotor variables have been influenced by body mass. To examine animals that vary widely in body mass, these studies have included taxa that differ in their locomotor adaptations and phylogenetic relatedness. Because these sources of diversity could obscure the effects of body mass,this study was designed to test the effects of adaptive differences in limb proportions and phylogeny, as well as body mass, on locomotor kinematics and extensor muscle mechanical advantage. More specifically, two hypotheses were tested in a sample of closely related animals: (i) that, among animals with similar body mass, those with longer limb segments should adopt more extended limb postures to moderate the joint and midshaft bending moments that they experience, and (ii) that body mass will have similar influences on joint posture and joint moments in closely related and diverse mammalian samples. Three-dimensional kinematic and synchronous force-platform data were collected for six individual cercopithecine monkeys ranging in mass from 4kg to 24kg and at a range of walking speeds. Comparisons among three monkeys with similar body mass but different limb segment lengths reveal a significant effect of limb proportion on posture. That is, animals with longer limbs frequently use more extended limb postures and can have correspondingly lower joint moments. The scaling of locomotor variables across the entire sample of closely related monkeys was generally similar to published results for a diverse sample of mammals, with larger monkeys having more extended limb postures, lower joint moments and greater effective mechanical advantage (EMA) for their limb extensor musculature. Ankle EMA, however, did not increase with body mass in the primate sample, suggesting that clade-specific adaptive differences (e.g. the use of arboreal supports by primates) may constrain the effects of body mass.

scholarly journals Low effective mechanical advantage of giraffes’ limbs during walking reveals trade-off between limb length and locomotor performance

2021 ◽  
Author(s):  
Christopher Basu ◽  
John R. Hutchinson
Keyword(s):  
Body Mass ◽  
Inverse Dynamics ◽  
Limb Length ◽  
Segment Length ◽  
Mechanical Advantage ◽  
Walking Gait ◽  
Moment Arms ◽  
Athletic Ability ◽  
Close Relatives ◽  
Similar Body

AbstractGiraffes (Giraffa camelopardalis) possess specialised locomotor morphology, namely elongate and gracile distal limbs. Whilst this contributes to their overall height (and enhanced feeding behaviour), we propose that the combination of long limb segments and modest muscle lever arms results in low effective mechanical advantage (EMA, the ratio of in-lever to out-lever moment arms), when compared with other cursorial mammals. To test this, we used a combination of experimentally measured kinematics and ground rection forces (GRFs), musculoskeletal modelling, and inverse dynamics to calculate giraffe forelimb EMA during walking. Giraffes walk with an EMA of 0.34 (±0.05 S.D.), with no evident association with speed within their walking gait. Giraffe EMA was markedly below the expectations extrapolated from other mammals ranging from 0.03 – 297 kg, and provides further evidence that EMA plateaus or even diminishes in mammals exceeding horse size. We further tested the idea that limb segment length is a factor which determines EMA, by modelling the GRF and muscle moment arms in the extinct giraffid Sivatherium giganteum and the other extant giraffid Okapia johnstoni. Giraffa and Okapia shared similar EMA, despite a 4-6 fold difference in body mass (Okapia EMA = 0.38). In contrast Sivatherium, sharing a similar body mass to Giraffa, had greater EMA (0.59), which we propose reflects behavioural differences, such athletic performance. Our modelling approach suggests that limb length is a determinant of GRF moment arm magnitude, and that unless muscle moment arms scale isometrically with limb length, tall mammals are prone to low EMA.Significance StatementGiraffes are the tallest living animals - using their height to access food unavailable to their competitors. It is not clear how their specialized anatomy impacts their athletic ability. We made musculoskeletal models of the forelimbs from a giraffe and two close relatives, and used motion-capture and forceplate data to measure how efficient they are when walking in a straight line. A horse for example, uses just 1 unit of muscle force to oppose 1 unit of force on the ground. Giraffe limbs however are comparatively disadvantaged – their muscles must develop 3 units of force to oppose 1 unit of force at the ground. This explains why giraffes walk and run at relatively slow speeds.

Three-Dimensional Joint Moments Analysis in a Vertical Quadrupedal Posture Associated with a Leg Release

1997 ◽  
Vol 105 (2) ◽  
pp. 136-143 ◽  
Author(s):  
F. Quaine ◽  
L. Martin ◽  
M. Leroux ◽  
P. Allard ◽  
J. P. Blanchi
Keyword(s):  
Three Dimensional ◽  
Joint Moments

Stiffened Hangers: an Often Overlooked Tool for Conceptual Design of Tied-Arch Footbridges

2021 ◽  
Author(s):  
Juan José Jorquera-Lucerga ◽  
Juan Manuel GARCÍA-GUERRERO
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Structural Response ◽  
Bending Moments ◽  
Structural Element ◽  
Axial Forces ◽  
Limited Effectiveness ◽  
Out Of Plane ◽  
Arch Bridges ◽  
Fixed End

<p>In tied-arch bridges, the way the arch and the deck are connected may become crucial. The deck is usually suspended from hangers made out of steel pinned cables capable of resisting axial forces only. However, a proper structural response, (both in-plane and out-of-plane) may be ensured by fixing and stiffening the hangers in order to resist, additionally, shear forces and bending moments. This paper studies the effect of different pinned and stiffened hanger arrangements on the structural behavior of the tied-arch footbridges, with the intention of providing designers with useful tools at the early steps of design. As a major conclusion, regarding the in-plane behavior, hangers composed of cables (either with vertical, Nielsen-Löhse or network arrangements) are recommended due to its low cost and ease of erection. Alternatively, longitudinally stiffened hangers, fixed at both ends, can be used. Regarding the out-of-plane behavior, and in addition to three-dimensional arrangements of cables, of limited effectiveness, transversally stiffened hangers fixed at both ends are the most efficient arrangement. A configuration almost as efficient can be achieved by locating a hinge at the end corresponding to the most flexible structural element (normally the arch). Its efficiency is further improved if the cross-section tapers from the fixed end to the pinned end.</p>

scholarly journals A comparative study of different acceleration sensors in measuring energy consumption of human martial arts

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Qixia Jia ◽  
Zengyin Yan ◽  
Yongyong Wang
Keyword(s):  
Body Weight ◽  
Energy Consumption ◽  
Body Mass ◽  
Martial Arts ◽  
Three Dimensional ◽  
Male Adolescents ◽  
Normal Body ◽  
Acceleration Sensors ◽  
Normal Body Weight ◽  
Mass Group

AbstractAt present, there are many acceleration sensors for measuring human martial arts in the market. However, due to the inaccurate measurement of some acceleration sensors, people who love martial arts are deeply troubled and unable to find an excellent acceleration sensor specifically for energy consumption detection of human martial arts. The development of this sensor is imminent, which is of great significance for the comparative study of energy consumption measurement of human martial arts in our country. In this study, 160 students aged 11–14 years were selected, and the subjects were divided into normal body mass group and abnormal body mass group. Of the 96 male adolescents, 32 were obese body mass, which was determined as male abnormal body mass Group; 64 male adolescents were normal body weight and male normal body weight group; female 64 adolescents were normal body weight and set as female normal body mass group. Using a built-in accelerometer and a mobile phone three-dimensional accelerometer, the subjects were subjected to a 3–8 km/h human martial arts exercise load test (each speed is continuously performed for 5 min). The two acceleration sensors collectively assess the accuracy of the prediction of the use of force in human martial arts experiments. The average power consumption of human art exercises uses a frequency of 60 times/min, 90 times/min and 120 times/min compared to two acceleration sensors. Test results show that the data points for the mobile accelerator eraser are scattered, and the distance between the data varies. The data points of the three-dimensional acceleration sensor are more concentrated and present a certain trend. The use of three-dimensional acceleration sensors to measure martial arts can fully reflect the energy consumption of human activities, and achieve an energy consumption measurement accuracy of more than 94%.

scholarly journals A Three-Dimensional Skeletal Reconstruction of the Stem Amniote Orobates pabsti (Diadectidae): Analyses of Body Mass, Centre of Mass Position, and Joint Mobility

PLoS ONE ◽  
2015 ◽  
Vol 10 (9) ◽  
pp. e0137284 ◽  
Author(s):  
John A. Nyakatura ◽  
Vivian R. Allen ◽  
Jonas Lauströer ◽  
Amir Andikfar ◽  
Marek Danczak ◽  
...  
Keyword(s):  
Body Mass ◽  
Three Dimensional ◽  
Joint Mobility ◽  
Centre Of Mass ◽  
Mass Centre ◽  
Mass Position ◽  
Skeletal Reconstruction

scholarly journals Control Reference Parameter for Stance Assistance Using a Passive Controlled Ankle Foot Orthosis—A Preliminary Study

2019 ◽  
Vol 9 (20) ◽  
pp. 4416 ◽  
Author(s):  
Dimas Adiputra ◽  
Mohd Azizi Abdul Rahman ◽  
Ubaidillah ◽  
Saiful Amri Mazlan ◽  
Nurhazimah Nazmi ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Standard Error ◽  
Walking Speed ◽  
Parameters Estimation ◽  
Ankle Foot Orthosis ◽  
Preliminary Study ◽  
Reference Parameters ◽  
Walking Speeds ◽  
Foot Orthosis

This paper aims to present a preliminary study of control reference parameters for stance assistance among different subjects and walking speeds using a passive-controlled ankle foot orthosis. Four young male able-bodied subjects with varying body mass indexes (23.842 ± 4.827) walked in three walking speeds of 1, 3, and 5 km/h. Two control references, average ankle torque (aMa), and ankle angular velocity (aω), which can be implemented using a magnetorheological brake, were measured. Regression analysis was conducted to identify suitable control references in the three different phases of the stance. The results showed that aω has greater correlation (p) with body mass index and walking speed compared to aMa in the whole stance phase (p1(aω) = 0.666 > p1(aMa) = 0.560, p2(aω) = 0.837 > p2(aMa) = 0.277, and p3(aω) = 0.839 > p3(aMa) = 0.369). The estimation standard error (Se) of the aMa was found to be generally higher than of aω (Se1(aMa) = 2.251 > Se1(aω) = 0.786, Se2(aMa) = 1.236 > Se2(aω) = 0.231, Se3(aMa) = 0.696 < Se3(aω) = 0.755). Future studies should perform aω estimation based on body mass index and walking speed, as suggested by the higher correlation and lower standard error as compared to aMa. The number of subjects and walking speed scenarios should also be increased to reduce the standard error of control reference parameters estimation.

Three-dimensional analysis of anchored wall with concrete bearing pads

2020 ◽  
Vol 18 (6) ◽  
pp. 1469-1486
Author(s):  
Hamed Arefizadeh ◽  
Hadi Shahir
Keyword(s):  
Design Methodology ◽  
Three Dimensional ◽  
Bending Moments ◽  
Dimensional Model ◽  
Discrete Elements ◽  
Three Dimensional Model ◽  
Content Type ◽  
Finite Element Software ◽  
Internal Forces ◽  
Soldier Pile

Purpose Anchorage with concrete bearing pad is commonly used in Iran for stabilization of excavations because of the ease of construction, less costs and less time consumption than the soldier pile method. In this method, a wall facing which includes the concrete bearing pads at the location of the anchors and a shotcrete layer between the bearing pads is constructed parallel to the excavation operation similar to the nailing method. Design/methodology/approach In this paper, using the finite element software Abaqus, a three-dimensional model of the above-mentioned type of wall is constructed, and the effect of spacing and size of bearing pads on the wall behavior is discussed. Findings According to the obtained results, the size of the concrete bearing pads has little effect on wall deformations, but the internal forces and bending moments developed in the shotcrete layer between the bearing pads are greatly influenced by the bearing pads dimensions and spacing. Originality/value Owing to the discrete elements of the wall facing, the behavior of this system is completely three-dimensional.

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