scholarly journals How predation shaped fish: the impact of fin spines on body form evolution across teleosts

2015 ◽  
Vol 282 (1819) ◽  
pp. 20151428 ◽  
Author(s):  
S. A. Price ◽  
S. T. Friedman ◽  
P. C. Wainwright

It is well known that predators can induce morphological changes in some fish: individuals exposed to predation cues increase body depth and the length of spines. We hypothesize that these structures may evolve synergistically, as together, these traits will further enlarge the body dimensions of the fish that gape-limited predators must overcome. We therefore expect that the orientation of the spines will predict which body dimension increases in the presence of predators. Using phylogenetic comparative methods, we tested this prediction on the macroevolutionary scale across 347 teleost families, which display considerable variation in fin spines, body depth and width. Consistent with our predictions, we demonstrate that fin spines on the vertical plane (dorsal and anal fins) are associated with a deeper-bodied optimum. Lineages with spines on the horizontal plane (pectoral fins) are associated with a wider-bodied optimum. Optimal body dimensions across lineages without spines paralleling the body dimension match the allometric expectation. Additionally, lineages with longer spines have deeper and wider body dimensions. This evolutionary relationship between fin spines and body dimensions across teleosts reveals functional synergy between these two traits and a potential macroevolutionary signature of predation on the evolutionary dynamics of body shape.

Author(s):  
M. S. Bugaeva ◽  
O. I. Bondarev ◽  
N. N. Mikhailova ◽  
L. G. Gorokhova

Introduction. The impact on the body of such factors of the production environment as coal-rock dust and fluorine compounds leads to certain shift s in strict indicators of homeostasis at the system level. Maintaining the relative constancy of the internal environment of the body is provided by the functional consistency of all organs and systems, the leading of which is the liver. Organ repair plays a crucial role in restoring the structure of genetic material and maintaining normal cell viability. When this mechanism is damaged, the compensatory capabilities of the organ are disrupted, homeostasis is disrupted at the cellular and organizational levels, and the development of the main pathological processes is noted.The aim of the study is to compare the morphological mechanisms of maintaining structural homeostasis of the liver in the dynamics of the impact on the body of coal-rock dust and sodium fluoride.Materials and methods. Experimental studies were conducted on adult white male laboratory rats. Features of morphological mechanisms for maintaining structural homeostasis of the liver in the dynamics of exposure to coal-rock dust and sodium fluoride were studied on experimental models of pneumoconiosis and fluoride intoxication. For histological examination in experimental animals, liver sampling was performed after 1, 3, 6, 9, 12 weeks of the experiment.Results. The specificity of morphological changes in the liver depending on the harmful production factor was revealed. It is shown that chronic exposure to coal-rock dust and sodium fluoride is characterized by the development of similar morphological changes in the liver and its vessels from the predominance of the initial compensatory-adaptive to pronounced violations of the stromal and parenchymal components. Long-term inhalation of coal-rock dust at 1–3 weeks of seeding triggers adaptive mechanisms in the liver in the form of increased functional activity of cells, formation of double-core hepatocytes, activation of immunocompetent cells and endotheliocytes, ensuring the preservation of the parenchyma and the general morphostructure of the organ until the 12th week of the experiment. Exposure to sodium fluoride leads to early disruption of liver compensatory mechanisms and the development of dystrophic changes in the parenchyma with the formation of necrosis foci as early as the 6th week of the experiment.Conclusions. The study of mechanisms for compensating the liver structure in conditions of long-term exposure to coal-rock dust and sodium fluoride, as well as processes that indicate their failure, and the timing of their occurrence, is of theoretical and practical importance for developing recommendations for the timely prevention and correction of pathological conditions developing in employees of the aluminum and coal industry.The authors declare no conflict of interests.


2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Wanyan Li ◽  
Xuelian Xiang ◽  
Bingxin Li ◽  
Yifei Wang ◽  
Long Qian ◽  
...  

Polysaccharide of Atractylodes macrocephala Koidz (PAMK) is a biologically active component of Atractylodes macrocephala, which has the effect of maintaining the immune homeostasis of the body. Therefore, this study constructed a model of PAMK to relieve LPS-induced gosling enteritis and observed the morphological changes of the small intestine after HE staining. ELISA was used to detect serum CRP, IL-1β, IL-6, and TNF-α levels; immunohistochemistry was used to detect the positive rate of IgA in the small intestine; TLR4, occludin, ZO-1, cytokines, and immunoglobulin mRNA expression in the small intestine were detected by qPCR; and intestinal flora of gosling excrement was analyzed by 16S rDNA sequencing to analyze the protective effect of PAMK on goslings enteritis and the impact on intestinal flora. The results showed that PAMK relieves LPS-induced gosling enteritis by maintaining the small intestine morphology, cytokine, tight junctions, and immunoglobulin relatively stable and improving the disorder of intestinal flora.


Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 5046 ◽  
Author(s):  
Lvwen Huang ◽  
Han Guo ◽  
Qinqin Rao ◽  
Zixia Hou ◽  
Shuqin Li ◽  
...  

For the time-consuming and stressful body measuring task of Qinchuan cattle and farmers, the demand for the automatic measurement of body dimensions has become more and more urgent. It is necessary to explore automatic measurements with deep learning to improve breeding efficiency and promote the development of industry. In this paper, a novel approach to measuring the body dimensions of live Qinchuan cattle with on transfer learning is proposed. Deep learning of the Kd-network was trained with classical three-dimensional (3D) point cloud datasets (PCD) of the ShapeNet datasets. After a series of processes of PCD sensed by the light detection and ranging (LiDAR) sensor, the cattle silhouettes could be extracted, which after augmentation could be applied as an input layer to the Kd-network. With the output of a convolutional layer of the trained deep model, the output layer of the deep model could be applied to pre-train the full connection network. The TrAdaBoost algorithm was employed to transfer the pre-trained convolutional layer and full connection of the deep model. To classify and recognize the PCD of the cattle silhouette, the average accuracy rate after training with transfer learning could reach up to 93.6%. On the basis of silhouette extraction, the candidate region of the feature surface shape could be extracted with mean curvature and Gaussian curvature. After the computation of the FPFH (fast point feature histogram) of the surface shape, the center of the feature surface could be recognized and the body dimensions of the cattle could finally be calculated. The experimental results showed that the comprehensive error of body dimensions was close to 2%, which could provide a feasible approach to the non-contact observations of the bodies of large physique livestock without any human intervention.


2021 ◽  
Vol 26 (2(49)) ◽  
pp. 89-97
Author(s):  
R. V. Yanko

Introduction: Despite the well-studied effect of alimentary deprivation on the body, the literature data on its effect on functional activity and, in particular, on morphological changes in the thyroid gland are single and often contradictory, which does not allow unambiguous conclusions. All this requires a more detailed study of the role and mechanisms of the impact of restricted nutrition on the thyroid gland. Aim: To investigate the effect of alimentary deprivation on morphological changes in the thyroid gland of young rats. Methods: The study was conducted on 24 male Wistar rats aged 3 months. Rats of all groups were in uniform conditions, on a standard diet. Animals of the experimental group, for 28 days, received a diet reduced by 30 %. Work with rats was carried out in accordance with the principles of the Declaration of Helsinki. Histological preparations were made from the central areas of the thyroid tissue according to the standard method. Using a digital camera, the micropreparations were photographed under a Nikon Eclipse E 100 microscope (Japan). Morphometry was performed using a computer program "Image J". Results: Histological analysis of the rat's thyroid gland affected by alimentary deprivation revealed that it had an unchanged physiological structure. The follicles were mostly of oval shape and of various sizes. Colloid in the follicles of experimental animals is of moderate density and contains numerous resorption vacuoles. Thyroid cells are of prismatic and cubic shape. It was found that in the thyroid gland of experimental rats the area of ​​follicles, colloid, their inner diameter decreases, the height of thyrocytes increases, the stereological resorption index increases and the colloid accumulation index decreases, the number of interfollicular islands increases. Also in experimental animals there was a decrease in the width of the interlobar and interfollicular connective tissue. Conclusion: In rats fed on a reduced diet, morphological signs of increased functional activity of the thyroid gland were found.


Author(s):  
Joshua Hooper ◽  
Martin Garcia ◽  
Paul Pena ◽  
Ayse Tekes

Abstract This study presents the design and development of a compliant multi-link hopping mechanism actuated by a single DC motor. Two main design goals are to have a single piece designed main body for the jumping robot and a passive stabilizer to allow consecutive jumps. Mechanism consists of monolithically designed large deflecting main body incorporating the gears and initially curved flexure hinge. Due to the limitations of the design goal, revolute motion between top and bottom legs on the main body are realized by a compliant link which replaces the need of ball bearings. Also, continuous energy store and release during jumping is ensured by the same flexure hinges. Passive self-righting cage is attached to the bottom of the main body to maintain upright position both in landing and takeoff. The cage allows the center of mass to stay in the vertical plane to prevent tilting. During landing, cage absorbs the impact and allows the main body to roll to its initial configuration so that the robot can complete jumping. Mechanism parts including the cage are 3D printed using PETG. Design optimization of the body parts including the rigid legs and flexure hinges are analyzed both experimentally and analytically. Finite element analysis is performed to calculate the equivalent stiffness and natural frequency of the jumping robot and simplified mathematical model is derived using rigid body dynamics.


2019 ◽  
Vol 31 (3) ◽  
pp. 415-430 ◽  
Author(s):  
Hyunsook Han

Purpose The purpose of this paper is to investigate the chest girth and height related to men’s upper body dimensions to develop men’s grading system for semi-customized clothing. Design/methodology/approach A data set of the 3,012 men between the age group of 18 and 59 years from 6th Size Korea was used in this study. The men’s upper body dimensions were tested in terms of five horizontal lengths, seven circumferences and seven vertical lengths. Experiment and data analysis were carried out with two methods: one is multiple linear regression with chest girth and height as each independent variable and the other is calculating variation among chest girth size groups and height size groups, respectively. Findings Regression analysis showed that some horizontal lengths are affected not only by chest girth, but also by height, and some vertical lengths are affected not only by height, but also by chest girth. In variation analysis it was found that the variation value for each part of the body is different and it was observed that with an increase in chest girth vertical length also increases. In variation analysis of height, it is found that some horizontal body dimensions and hip girth increase with an increase in height. In the comparison of upper body dimension variation among height groups with the size based on the chest girth, we found that a tall person who already has long vertical length is less affected by the increase in dimensions by increases in their horizontal girth than a short person. Originality/value The findings showed detailed numerical body shape changes according to chest girth and height, and it may be used as the basis for determining pattern grading values by chest girth or height.


2014 ◽  
Vol 606 ◽  
pp. 247-251
Author(s):  
Yanti Sri Rejeki ◽  
Nur Rahman As'ad ◽  
Eri Achiraeniwati

Cibaduyut is the center of the shoe industry in the city of Bandung, West Java Indonesia. Shoes that are produced here are mostly produced by small-scale industries scattered in Cibaduyut area. The process of making shoes that are made by small industries, still uses simple facilities and techniques, with no attention to the aspect of comfort, safety and occupational health. The work facilities used today causes inconvenience to employees in their work. The results of the survey (by distributing Discomfort Questionnairre), we obtained information stating that the workers complained on several problems concerning the body dimension during the work progress. From this illustration we can say that it is necessary to evaluate the working posture to minimize the risks arising from the work by methods RULA (Rapid Upper Limb Assessment). The results obtained from Rula shows some works that are done are at the level 4, which means that this work belongs to high risk and needs to be improved immediately. Therefore we should provide the design facilities such as desk to work in pattern, sole, and finishing work station which are needed to improve posture. The size of product design tailored to the size of the body dimensions of workers with anthropometric methods. The design of the facility will improve the posture of workers in their work.


2020 ◽  
Author(s):  
Zeus Gracia-Tabuenca ◽  
Martha Beatriz Moreno ◽  
Fernando Barrios ◽  
Sarael Alcauter

AbstractAdolescence is a developmental period that dramatically impacts body and behavior, with pubertal hormones playing an important role not only in the morphological changes in the body but also in brain structure and function. Understanding brain development during adolescence has become a priority in neuroscience because it coincides with the onset of many psychiatric and behavioral disorders. However, little is known about how puberty influences the brain functional connectome. In this study, taking a longitudinal human sample of typically developing children and adolescents (of both sexes), we demonstrate that the development of the brain functional connectome better fits pubertal status than chronological age. In particular, centrality, segregation, efficiency, and integration of the brain functional connectome increase after the onset of the pubertal markers. We found that these effects are stronger in attention and task control networks. Lastly, after controlling for this effect, we showed that functional connectivity between these networks is related to better performance in cognitive flexibility. This study points out the importance of considering longitudinal nonlinear trends when exploring developmental trajectories, and emphasizes the impact of puberty on the functional organization of the brain in adolescence.Significance StatementUnderstanding the brain organization along development is a crucial challenge for Neuroscience. In particular, during adolescence there is a great impact in body and cognitive functions as well as substantial incidence of mental health disruptions. Here, we tested how brain organization changes along this period based on the properties of the functional connectome in a longitudinal pediatric sample. We found a nonlinear increase in the connectivity and the brain network efficiency, particularly after the onset of puberty. These effects were more prominent in association networks. In addition, higher connectivity in those areas was associated with better performance in cognitive flexibility. These results demonstrate the importance of considering pubertal assessment as well as nonlinear trends in developmental studies.


2019 ◽  
Vol 98 (11) ◽  
pp. 1245-1250 ◽  
Author(s):  
Vera A. Vokina ◽  
M. A. Novikov ◽  
T. A. Elfimova ◽  
E. S. Bogomolova ◽  
A. N. Alekseenko ◽  
...  

Introduction. The study of the mechanisms of action of combustion products released during natural fires on the body and the development of appropriate preventive measures is an actual hygienic problem at the present stage. Material and methods. Experimental modeling of landscape fire was carried out for 7 days, 4 hours per day. Forest fuel, which is a living ground cover and plant residues, was used as a combustible substrate. The concentration of carbon monoxide, formaldehyde, furfural, and acetaldehyde was determined in the exposure chamber, the general qualitative composition of air and the target qualitative analysis for volatile aldehydes and ketones were carried out. After exposure rat behavior was observed through an open field test and Morris water maze, histological studies of brain tissue were done. Results. During the experiment changes in the structure of the behavior of white rats exposed to smoke were established to be characterized by a decrease in motor and exploratory activity, and an increase in the level of anxiety in females was also observed. When testing in the water maze of Morris revealed violations of spatial memory and the ability to navigational learning. Histological examination of the cerebral cortex in animals of the experimental groups revealed multiple foci of neuronophagy, expansion of perivascular spaces, and the development of glial cell replacement hyperplasia was noted. Conclusion. The results indicate the presence of a neurotoxic effect of combustion products, characterized by a decrease in the motor activity of animals, increased anxiety and impaired memory processes, as well as morphological changes in the brain tissue of white rats. However, in order to reveal the role of the impact of a complex of substances released during forest fires, their contribution to morphological and functional disorders, furthermore in-depth studies are required.


2018 ◽  
Vol 15 (2) ◽  
pp. 1-20
Author(s):  
Sabri Embi ◽  
Zurina Shafii

The purpose of this study is to examine the impact of Shariah governance and corporate governance (CG) on the risk management practices (RMPs) of local Islamic banks and foreign Islamic banks operating in Malaysia. The Shariah governance comprises the Shariah review (SR) and Shariah audit (SA) variables. The study also evaluates the level of RMPs, CG, SR, and SA between these two type of banks. With the aid of SPSS version 20, the items for RMPs, CG, SR, and SA were subjected to principal component analysis (PCA). From the PCA, one component or factor was extracted each for the CG, SR, and RMPs while another two factors were extracted for the SA. Primary data was collected using a self-administered survey questionnaire. The questionnaire covers four aspects ; CG, SR, SA, and RMPs. The data received from the 300 usable questionnaires were subjected to correlation and regression analyses as well as an independent t-test. The result of correlation analysis shows that all the four variables have large positive correlations with each other indicating a strong and significant relationship between them. From the regression analysis undertaken, CG, SR, and SA together explained 52.3 percent of the RMPs and CG emerged as the most influential variable that impacts the RMPs. The independent t-test carried out shows that there were significant differences in the CG and SA between the local and foreign Islamic banks. However, there were no significant differences between the two types of the bank in relation to SR and RMPs. The study has contributed to the body of knowledge and is beneficial to academicians, industry players, regulators, and other stakeholders.


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