scholarly journals Stock identification of Kawakawa Euthynnus affinis (Cantor, 1849) from Peninsular Malaysia using discriminant analysis

2022 ◽  
Vol 956 (1) ◽  
pp. 012002
Author(s):  
Kh Binashikhbubkr ◽  
D Naim

Abstract Small epipelagic and migratory, Eutynnus affinis (kawakawa) is one of the commercially significant tunas of Indo-Pacific’s tropical and subtropical waters. Consequently, successful management must ensure its sustainability. Unfortunately, the management and stock structure of certain migratory species in the area are not clear. The current study aimed to discriminate the E. affinis through body shape variations and to evaluate the variations among seven populations of E. affinis. A total of 114 individuals of E. affinis collected from two main geographic area, Straits of Malacca and South China Sea. Multivariate analyses, such as discriminant function analyses (DFA) of 12 morphometric characters was carried out to discriminate seven populations of E. affinis. The results revealed there is a significant variation among the body shape and seven populations of E. affinis. The average shapes of populations from Terengganu, Kelantan, and Johor were approximately similar to each other. In contrast, the average shapes of populations from Selangor were separated. This present study is the first report using morphometric method conducted on E. affinis from Peninsular Malaysian waters.

2019 ◽  
Vol 53 (4) ◽  
pp. 325-334
Author(s):  
V. N. Peskov ◽  
N. A. Petrenko ◽  
V. Yu. Reminnyi

Abstract We study size-at-age and sexual variability of morphometric characteristics of the marsh frog. According to the size of the body, males were divided into three size-age groups (juvenis, subadultus, adultus), females — into four groups (juvenis, subadultus, adultus, adultus-I). We found that the chronological age of frogs (skeletochronology) does not always correspond to their biological age (size and proportions of the body). We noted that the semi-adult males are reliably larger than females by mean values of 26 studied morphometric characters. Males and females of “adultus” group do not differ by linear body size, significant differences were found in body proportions (7 characters). For the females of “adultus-I” group, the mean values of 26 characters are significantly larger than for “adultus” males. The results of our study showed that with the age of the marsh frog, the level of exhibition, directionality and structure of morphometric sex differences changes.


2020 ◽  
Author(s):  
Jaimie Krems ◽  
Steven L. Neuberg

Heavier bodies—particularly female bodies—are stigmatized. Such fat stigma is pervasive, painful to experience, and may even facilitate weight gain, thereby perpetuating the obesity-stigma cycle. Leveraging research on functionally distinct forms of fat (deposited on different parts of the body), we propose that body shape plays an important but largely underappreciated role in fat stigma, above and beyond fat amount. Across three samples varying in participant ethnicity (White and Black Americans) and nation (U.S., India), patterns of fat stigma reveal that, as hypothesized, participants differently stigmatized equally-overweight or -obese female targets as a function of target shape, sometimes even more strongly stigmatizing targets with less rather than more body mass. Such findings suggest value in updating our understanding of fat stigma to include body shape and in querying a predominating, but often implicit, theoretical assumption that people simply view all fat as bad (and more fat as worse).


Author(s):  
Johan Roenby ◽  
Hassan Aref

The model of body–vortex interactions, where the fluid flow is planar, ideal and unbounded, and the vortex is a point vortex, is studied. The body may have a constant circulation around it. The governing equations for the general case of a freely moving body of arbitrary shape and mass density and an arbitrary number of point vortices are presented. The case of a body and a single vortex is then investigated numerically in detail. In this paper, the body is a homogeneous, elliptical cylinder. For large body–vortex separations, the system behaves much like a vortex pair regardless of body shape. The case of a circle is integrable. As the body is made slightly elliptic, a chaotic region grows from an unstable relative equilibrium of the circle-vortex case. The case of a cylindrical body of any shape moving in fluid otherwise at rest is also integrable. A second transition to chaos arises from the limit between rocking and tumbling motion of the body known in this case. In both instances, the chaos may be detected both in the body motion and in the vortex motion. The effect of increasing body mass at a fixed body shape is to damp the chaos.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mark Hermes ◽  
Mitul Luhar

AbstractIntertidal sea stars often function in environments with extreme hydrodynamic loads that can compromise their ability to remain attached to surfaces. While behavioral responses such as burrowing into sand or sheltering in rock crevices can help minimize hydrodynamic loads, previous work shows that sea stars also alter body shape in response to flow conditions. This morphological plasticity suggests that sea star body shape may play an important hydrodynamic role. In this study, we measured the fluid forces acting on surface-mounted sea star and spherical dome models in water channel tests. All sea star models created downforce, i.e., the fluid pushed the body towards the surface. In contrast, the spherical dome generated lift. We also used Particle Image Velocimetry (PIV) to measure the midplane flow field around the models. Control volume analyses based on the PIV data show that downforce arises because the sea star bodies serve as ramps that divert fluid away from the surface. These observations are further rationalized using force predictions and flow visualizations from numerical simulations. The discovery of downforce generation could explain why sea stars are shaped as they are: the pentaradial geometry aids attachment to surfaces in the presence of high hydrodynamic loads.


Author(s):  
Peter J. Cooper ◽  
Melanie J. Taylor ◽  
Zafra Cooper ◽  
Christopher G. Fairbum

1988 ◽  
Vol 24 (4) ◽  
pp. 528-528
Author(s):  
W J M Gerver ◽  
N M Drayer ◽  
W Schaafsma ◽  
N M Drayer
Keyword(s):  

2009 ◽  
Vol 9 (3) ◽  
pp. 331-338 ◽  
Author(s):  
Maria Aparecida Conti ◽  
Táki Athanássios Cordás ◽  
Maria do Rosário Dias de Oliveira Latorre

OBJECTIVES: to produce evidence of the validity and reliability of the Body Shape Questionnaire (BSQ) - a tool for measuring an individual's attitude towards his or her body image. METHODS: the study covered 386 young people of both sexes aged between 10 and 18 from a private school and used self-applied questionnaires and anthropometric evaluation. It evaluated the internal consistency, the discriminant validity for differences from the means, according to nutritional status (underweight, eutrophic, overweight and obese), the concurrent validity by way of Spearman's correlation coefficient between the scale and the Body Mass Index (BMI), the waist-hip circumference ratio (WHR) and the waist circumference (WC). Reliability was tested using Wilcoxon's Test, the intraclass correlation coefficient and the Bland-Altman figures. RESULTS: the BSQ displayed good internal consistency (±=0.96) and was capable of discriminating among the total population, boys and girls, according to nutritional status (p<0.001). It correlated with the BMI (r=0.41; p<0.001), WHR (r=-0.10; p=0.043) and WC (r=0.24; p<0.001) and its reliability was confirmed by intraclass correlation (r=0.91; p<0.001) for the total population. The questionnaire was easy to understand and could be completed quickly. CONCLUSIONS: the BSQ presented good results, thereby providing evidence of its validity and reliability. It is therefore recommended for evaluation of body image attitudes among adolescents.


Author(s):  
Karen S. Young ◽  
K. Han Kim ◽  
Sudhakar Rajulu

Objective This study aims to identify the change in anthropometric measurements during spaceflight due to microgravity exposure. Background Comprehensive and accurate anthropometric measurements are crucial to assess body shape and size changes in microgravity. However, only limited anthropometric data have been available from the astronauts in spaceflight. Methods A new photogrammetry-based technique in combination with a tape-measure method was used for anthropometric measurements from nine crewmembers on the International Space Station. Measurements included circumference and height for body segments (chest, waist, bicep, thigh, calf). The time-dependent variations were also assessed across pre-, in-, and postflight conditions. Results Stature showed a biphasic change with up to 3% increase at the early flight phase, followed by a steady phase during the remaining flight. Postflight measurements returned to a similar level of the preflight. Other linear measurements, including acromion height, showed similar trends. The chest, hip, thigh, and calf circumferences show overall decrease during the flight up to 11%, then returned close to the preflight measurement at postflight. Conclusion The measurements from this study provide critical information for the spacesuit and hardware design. The ground-based assessments for spacesuit fit needs to be revalidated and adjusted for in-flight extravehicular activities from this data. Application These data can be useful for space suit design as well as habitat, vehicle, and additional microgravity activities such as exercise, where the body shape changes can affect fit, performance, and human factors of the overall design.


2010 ◽  
Vol 8 (2) ◽  
pp. 299-310 ◽  
Author(s):  
Fernando Zaniolo Gibran

Based on a fish survey and preliminary underwater observations, 17 "morphotypes" were identified that characterize the morphological diversity found within 27 nektonic fish species sampled at São Sebastião Channel. Such "morphotypes" were studied using an ecomorphological approach, with the intention to investigate similarities and differences in shape and habits. Underwater field observations were also performed, to verify if the lifestyle of these species, such as vertical occupation of the water column and the habitat use, are in accordance with their distribution in the morphospace. The results, complemented with data from scientific literature on the taxonomy and phylogenies of these species, allowed discussing some of the typical cases of convergent and divergent evolution. Some of the ecomorphological clusters had no phylogenetic support although this is probably due to the environmental conditions in which theirs members have evolved. The body shape and fins positions of a fish clearly influence its ecological performance and habitat use, corroborating the ecomorphological hypothesis on the intimate link between phenotype and ecology.


Author(s):  
Julián F. Calderón-García ◽  
Raúl Roncero-Martín ◽  
Sergio Rico-Martín ◽  
Jorge M. De Nicolás-Jiménez ◽  
Fidel López-Espuela ◽  
...  

Introduction: The body roundness index (BRI) and a body shape index (ABSI) are novel anthropometric indices established to determine both the amount visceral adipose tissue and body fat. Objective: to investigate whether BRI and ABSI are better predictors of hypertension than body mass index (BMI), waist circumference (WC) or waist-to-height ratio (WHtR). Methods: A systematic search was conducted in the Scopus, PubMed and Web of Science databases up until 31 December 2020. Results: The estimated pooled area under curve [AUC (95% CI)] for BRI [0.67 (0.65–0.70)] for the prediction of hypertension were superior to that of ABSI (0.58 (0.56–0.60)), similar to that of BMI [0.67 (0.64–0.69)], and lower than those WC [0.68 (0.66–0.70)] and WHtR [0.68 (0.66–0.71)]. Nevertheless, the difference of BRI compared to WC and WHtR in the context of predicting hypertension was non-significant. ABSI was significantly lower (p < 0.05) than BRI, BMI, WC and WHtR. Similar findings were observed with the summary receiver operating characteristic curve (AUC-SROC). There were no significant differences between subgroups according to type of population or diagnostic criteria of hypertension. The diagnostic odds ratio (dORs) proved that increased BRI and ABSI were related with an elevated hypertension risk. Conclusions: BRI and ABSI have discriminatory power for hypertension in adult women and men from different populations. Although, WHtR and WC provided the best performance when assessing hypertension, no significant differences were found for BRI. Finally, BRI was significantly better predictor of hypertension than ABSI.


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