The Research and Analysis of the Body Structure Based on the Experiment of Bending Stiffness

2013 ◽  
Vol 631-632 ◽  
pp. 947-950
Author(s):  
Sheng Hui Peng ◽  
Qing Zhang Liu

According to the mechanical characteristics of the body structure, the experimental model and the bending test of the body is constructed to understand the static characteristics of the body structure, laying the foundation for the sensitivity analysis and the modification of structural dynamics .

2020 ◽  
Vol 15 (3) ◽  
pp. 117-125
Author(s):  
Jung-soo Park ◽  
Hyo Sung Kwak ◽  
Jin-Woo Kim

Purpose: Four key bench-top tests, including trackability, conformability, wall-apposition, and bending stiffness, were performed to understand the mechanical characteristics in 3 different types of stents applicable for treatment of intracranial atherosclerotic stenosis: Balloon-expandable D<sup>+</sup>Storm, Pro-Kinetic Energy, and self-expandable Wingspan stents.Materials and Methods: Trackability was assessed by measuring the tracking forces of each stent with its delivery systems. Conformability and wall apposition were quantified and analyzed using curved vessel models. A 3-point bending test was employed to evaluate bending stiffness.Results: D<sup>+</sup>Storm showed the lowest tracking forces while the conformability of the Wingspan stent was superior to that of the tested stents. Pro-Kinetic Energy and D<sup>+</sup>Storm had better wall apposition in curved vessels than the Wingspan stent. Bending stiffness of the Wingspan stent was notably lower, whereas no significant differences were found between D<sup>+</sup>Storm and Energy. Pro-Kinetic Energy and D<sup>+</sup>Storm not only indicated lower gap ratios between the struts and the vessel wall but also maintained good wall apposition even in the curved model.Conclusion: These bench-top measurements may provide clinicians with useful information in regard to selecting suitable stents for treatment of intracranial atherosclerotic stenosis.


2021 ◽  
Vol 80 (2) ◽  
pp. 76-85
Author(s):  
A. N. Skachkov ◽  
S. L. Samoshkin ◽  
S. D. Korshunov ◽  
D. A. Nikiforov ◽  
D. A. Romashov

Investigations of the frequency of bending vibrations of the car bodies of 61-4440 model range, which includes compartment cars, staff cars, non-compartment cars, coach cars, restaurant cars and others, are described. The bodies of all cars of this model range have the same overall dimensions and are made of corrosionresistant steels (stainless) with flat corrugated sheathing of the lower (under the window) belt.To assess the influence of the design features of stainless steel bodies on its bending stiffness and the parameters of bending vibrations in the vertical plane, a computational and experimental complex of works was carried out.After analyzing the calculation results and experimental data, proposals were developed and implemented to increase the bending stiffness of the metal body structure with stainless steel skin. To check the implemented proposals, complex tests were carried out to determine the parameters of bending vibrations of the metal structure of the experimental body. The tests were carried out according to the combined method developed by the authors. For this, a vibrator, installed in the console parts of the body, and impulse excitation were used.The results of testing the metal structure of the experimental body in comparison with the results of testing the car bodies of 61-4440 model range showed the effectiveness of the implemented proposals, namely: increasing the frequency of the first tone of bending vibrations by 18 %; decrease in the amplitude of vertical vibrations of the body structure at the frequency of the first tone from 12 to 50 %; decrease in the amplitude of the vertical accelerations of the metal structure of the body during oscillations at the frequency of the first tone approximately by 2 times; significant reduction in horizontal acceleration in the area of the middle section walls. The effectiveness of the implemented proposals for increasing the bending stiffness of the metal structure of the experimental body allows recommending them for the entire model range of 61-4440 cars.


2017 ◽  
Vol 1 (1) ◽  
pp. 115
Author(s):  
Sudar Kajin

Growth and development of the child have the nature of a thorough and intertwined relationships between components (health, nutrition, and environment). In general, child development can be grouped into three areas, namely cognitive, affective, and psychomotor, whereas biological growth which includes a change in the body structure. Body structure regarding the changes in bone structure, especially the long bones that have an impact on changes in body size, whereas changes in bodily functions is a result of hormonal changes that affect the physiological function .. The purpose of this development are: 1) Describe the product feasibility study التربية الجسمية for grade XI IPA at MAN I Mojokerto 2) Describe the development of learning tools using process skills can improve learning outcomes subjects التربية الجسمية class XI IPA at MAN I Mojokerto From the results of this development can be concluded: 1) results of expert validation and testing, the model approach process skills is fit for use for subjects of Physical Education, Sport and Health, because the products developed are not revised by experts but from the results of questionnaire of students stated that require revision are: (a) Improve the look model or change the learning strategy, and (b) improve the use of resources in implementing the model. 2) Product development learning tools using process skills can improve learning outcomes subjects التربية الجسمية class XI IPA at MAN I Mojokerto. From the class of the test increased learning completeness of Pre and Post Tests Tests are respectively 77.78% increase to 91.67%.


2020 ◽  
Vol 20 (2) ◽  
pp. 38-40
Author(s):  
A. Levitsky ◽  
A. Lapinska ◽  
I. Selivanskaya

The article analyzes the role of essential polyunsaturated fatty acids (PUFA), especially omega-3 series in humans and animals. The biosynthesis of essential PUFA in humans and animals is very limited, so they must be consumed with food (feed). Тhe ratio of omega-3 and omega-6 PUFA is very important. Biomembranes of animal cells contain about 30% PUFA with a ratio of ω-6/ ω-3 1-2. As this ratio increases, the physicochemical properties of biomembranes and the functional activity of their receptors change. The regulatory function of essential PUFA is that in the body under the action of oxygenase enzymes (cyclooxygenase, lipoxygenase) are formed extremely active hormone-like substances (eicosanoids and docosanoids), which affect a number of physiological processes: inflammation, immunity, metabolism. Moreover, ω-6 PUFA form eicosanoids, which have pro-inflammatory, immunosuppressive properties, and ω-3 PUFAs form eicosanoids and docosanoids, which have anti-inflammatory and immunostimulatory properties. Deficiency of essential PUFA, and especially ω-3 PUFA, leads to impaired development of the body and its state of health, which are manifestations of avitaminosis F. Prevention and treatment of avitaminosis F is carried out with drugs that contain PUFA. To create new, more effective vitamin F preparations, it is necessary to reproduce the model of vitamin F deficiency. An experimental model of vitamin F deficiency in white rats kept on a fat –free diet with the addition of coconut oil, which is almost completely free of unsaturated fatty acids, and saturated fatty acids make up almost 99 % of all fatty acids was developed. The total content of ω-6 PUFA (sum of linoleic and arachidonic acids), the content of ω-3 PUFA (α-linolenic, eicosapentaenoic and docosahexaenoic acids) in neutral lipids (triglycerides and cholesterol esters) defined. Тhe content of ω-6 PUFA under the influence of coconut oil decreased by 3.3 times, and the content of ω-3 PUFA - by 7.5 times. Тhe influence of coconut oil, the content of ω-6 PUFA decreased by 2.1 times, and the content of ω-3 PUFA - by 2.8 times. The most strongly reduces the content of ω-3 PUFA, namely eicosapentaenoic, coconut oil, starting from 5 %. Consumption of FFD with a content of 15 % coconut oil reduces the content of eicosapentaenoic acid to zero, ie we have an absolute deficiency of one of the most important essential PUFAs, which determined the presence of vitamin F deficiency.


2017 ◽  
Vol 54 ◽  
pp. 112-119
Author(s):  
L. M. Khmelnychy

The estimation of the first-born cows of Ukrainian Black-and-White dairy breed by the exterior type in the leading breeding herds of Cherkassy region by the method of linear classification (n = 566) has been carried out. The results of the evaluated animals by the 100-score system indicate that within the group of traits, the average level of assessment is "good with the plus". The animals have been differed by the good development of group features characterizing the dairy type (82.4 score), body condition (83.5 score), limbs (82.8 score), udder (82.7 score) and overall score (82.8 score). The degree of development 18 descriptive traits of the exterior of cows, has been predicted by the method of linear classification, indicates their significant intraherd variability. Animals have the moderate height, deep body and angularity. The rump angle, the angle of hock joint and the teats length, according to the variability of scores in the range of 17.8–22.4%, have an average optimal development. The level of scores for the rear width (5.9 score), attachment of the fore (6.3 score) and the rear parts (6.0 score) of the udder testifies to their good development. The body structure of the cows-firstborn has a sufficient description of the type traits that determine their milk yield. At the present stage of selection and breeding work due to the use of bull-sires different origins and breeding value on the local population livestock with significant genotype diversity, the degree of influence each of the hereditary factors in the overall variability of linear features has a scientific and practical significance. In our studies, the force of influence conditional bloodiness of the Holstein mother's breed in the overall fraction of variability of linear type traits within the exterior complexes and the overall assessment takes a significant percentage - from 24.9 to 31.5 with a high degree of reliability according to Fischer's criterion. Among the descriptive traits, the proportion of influence the conditional bloodiness of mother, which is confirmed by high statistical confidence, ranges from 14.4 to 19.8%, and refers to the traits important for breeding. The level of coefficients of influence the father's breeding value in the total phenotypic variability for some of the linear traits is high and reliable. First of all it concerns group traits of the exterior, the development of which is determined by the pedigree value of father by 37.1–41.8%, and the overall assessment of type – by 46.6%. The coefficients of influence father's breeding value in most of the descriptive traits have high reliability (P < 0,001). The coefficients of the force of influence father, depending on the heredity of Holstein for the linear traits of almost the same level as his pedigree value. Since in this case the organized factor is purebreed Holstein and crossbreed bulls-sires of domestic selection, the positive role of Holstein heredity in improving the exterior type of cows has been traced realistically. The necessity of linear breeding, as an effective method in the system of dairy cattle breeding, has been substantiated by reliable values of the coefficients of the force of influence of father's line on the linear traits of offspring (3.4–29.5%). Despite the significant variability of coefficients of the force of influence on the linear traits, most of them have a high level of reliability within the evaluated body parts important for selection. The effect of cows belonging to the maternal line on the development of features of the body structure is insignificant and unreliable (5.3–9.2%). In the process of breeding aimed at improving cows of dairy herd by the exterior type, the pedigree value of parents has been assessed according to the method of linear classification of their daughters and their belonging to perspective genealogical formations.


Author(s):  
Natalya L. Yakimova ◽  
Vladimir A. Pankov ◽  
Aleksandr V. Lizarev ◽  
Viktor S. Rukavishnikov ◽  
Marina V. Kuleshova ◽  
...  

Introduction. Vibration disease continues to occupy one of the leading places in the structure of professional pathology. In workers after the termination of contact with vibration generalization and progression of violations in an organism is noted. The pathogenetic mechanisms of the progredient course of disturbances in the nervous system in the post-contact period of vibration exposure remain insufficiently studied.The aim of the study was to test an experimental model of vibration exposure to assess the neurophysiological and morphological effects of vibration in rats in the dynamics of the post-contact period.Materials and methods. The work was performed on 168 white male outbred rats aged 3 months weighing 180–260 g. The vibration effect was carried out on a 40 Hz vibrating table for 60 days 5 times a week for 4 hours a day. Examination of animals was performed after the end of the physical factor, on the 30th, 60th and 120th day of the post-contact period. To assess the long-term neurophysiological and morphofunctional effects of vibration in rats, we used indicators of behavioral reactions, bioelectric activity of the somatosensory zone of the cerebral cortex, somatosensory and visual evoked potentials, parameters of muscle response, morphological parameters of nervous tissue.Results. In the dynamics of the post-contact period observed the preservation of violations of tentatively research, motor and emotional components of behavior. In the Central nervous system instability of activity of rhythms of an electroencephalogram, decrease in amplitude of visual evoked potentials, lengthening of latency of somatosensory evoked potentials, decrease in total number of normal neurons and astroglia is established. In the peripheral nervous system remained changes in indicators: increasing duration and latency, reducing the amplitude of the neuromuscular response.Conclusions: The experimental model allows us to study the long-term neurophysiological and morphological effects of vibration on the body. The formation and preservation of changes in behavioral activity, neurophysiological and morphological effects of vibration from the 30th to the 120th day of the post-contact period were confirmed.


2020 ◽  
Vol 20 (3) ◽  
pp. 446-452
Author(s):  
Seyed S. Mortazavi-Jahromi ◽  
Shahab Alizadeh ◽  
Mohammad H. Javanbakht ◽  
Abbas Mirshafiey

Background: This study aimed to investigate the effects of guluronic acid (G2013) on blood sugar, insulin, and gene expression profile of oxLDL receptors (SR-A, CD36, LOX-1, and CD68) in the experimental model of diabetes. Methods: 18 Sprague Dawley rats were randomly assigned to three groups of healthy control, diabetic control, and G2013 group. Diabetes was induced through intraperitoneal (IP) injection of 60 mg/kg streptozotocin. The subjects were IP treated with 25 mg/kg of G2013 per day for 28 days. The body weight, food intake, fasting blood glucose and insulin were measured. In addition, the expression of mentioned genes was investigated through quantitative real-time PCR. Results: The data showed that the final weight increased significantly in the G2013-treated subjects compared to the diabetic control (p < 0.05). The results indicated that final food intake significantly reduced in the G2013-treated subjects compared to the diabetic control (p < 0.05). The study findings also suggested that the final fasting blood glucose significantly reduced in the G2013-treated group, whereas the final fasting serum insulin level significantly increased in this group compared to the diabetic control (p < 0.05). Moreover, the gene expression levels of SR-A, CD36, LOX-1, and CD68 in the G2013 group significantly reduced compared to the diabetic control (p < 0.05). Conclusion: This study showed that G2013, could reduce blood glucose and increase insulin levels and reduce the gene expression level of oxLDL receptors. In addition, it may probably play an important role in reducing the severity of diabetes-induced inflammatory symptoms.


Author(s):  
Anatoliy Kulik ◽  
Konstantin Dergachov ◽  
Sergey Pasichnik ◽  
Sergey Yashyn

The subject of study is the physical processes of translational and angular motion of a two-wheeled experimental sample. The goal is to develop physical, mathematical, and graphic models of the translational and angular motions of a two-wheeled experimental sample as an object of automatic control. The objectives: to form physical models of a two-wheeled experimental sample; to develop a nonlinear mathematical description of the processes of translational and angular sample`s motions using the Lagrange approach; to obtain a linearized mathematical sample`s description as an object of automatic control in the state space and frequency domain; to generate graphic models in the form of structural diagrams in the time and frequency domains; to analyze the functional properties of an object of automatic control: stability, controllability, observability, structural and signal diagnosability concerning violations of the functional properties of electric drives and sensors of the angular position of the body and wheels. The methods of the study: the Lagrange method, Taylor series, state-space method, Laplace transformations, Lyapunov, Kalman criteria, and diagnosability criterion. The results: physical models of a two-wheeled experimental sample have been obtained in the form of a kinematic diagram of the mechanical part and the electric circuit of an electric drive; mathematical descriptions of translational and angular motions have been developed in nonlinear and linearized forms; structural diagrams have been developed; functional characteristics of a two-wheeled experimental model as an object of automatic control have been analyzed to solve problems of control algorithms synthesis. Conclusions. The scientific novelty lies in obtaining new models that describe the translational and angular motion of a two-wheeled experimental model as an object of automatic control. The obtained models differ from the known ones by considering the dynamic properties of sensors and electric drives, as well as the relationship of movements.


2013 ◽  
Vol 3 (12) ◽  
pp. 462 ◽  
Author(s):  
Alvaro L. Ronco ◽  
Eduardo De Stéfani

Since its discovery in the beginning of the XXth century, squalene has been recognized as an important link in metabolic pathways. More recently, it has been further recognized as an intermediate step in the biosynthesis of cholesterol. Its well known antioxidant capability, together with its ability to protect skin, improve the immune system, and modulate the lipid profile, confer a high potential to this natural substance, which is spread all across the body structure, though mainly in the epithelial tissues, and in particular the skin sebum. This review will focus mainly on its major properties, which are related to anticancer properties, the maintenance of the oxidation/antioxidation balance, and its antiaging capabilities. Although the substance was originally obtained from shark liver oil, it is currently possible to obtain useful amounts from vegetable sources like extra virgin olive oil, therefore avoiding the dependence on capturing the aforementioned animal species. Recognized as one of the key components of the Mediterranean dietary style, squalene is necessary to adequately manage oxygen and its derivatives in every cell of the body. Key words: aging, antioxidants, cancer, cholesterol, diet, olive oil, squalene


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