scholarly journals LIGHT AND THE MUSCLE TONUS OF INSECTS THE HELIOTROPIC MECHANISM

1918 ◽  
Vol 1 (1) ◽  
pp. 101-125 ◽  
Author(s):  
Walter E. Garrey
Keyword(s):  
Photochemical Reaction ◽  
Muscle Tension ◽  
The Body ◽  
Muscle Tonus ◽  
Complete Proof ◽  
Muscle Groups ◽  
The Relationship

The tonus of the muscles of heliotropic insects is due chiefly to the action of light; it is markedly decreased in the dark. Each eye controls the tonus of a different group of muscles on both sides of the body. Different areas of each eye likewise are related to the tonus of different muscle groups, and the relationship is entirely analogous to that of the otic labyrinth of vertebrates. Asymmetrical conditions of muscle tension are produced by any procedure which establishes an unequal photochemical reaction in the two eyes, by difference in illumination, by partial or complete blackening of one eye, or establishing unequal sensitiveness in the two eyes. The unbalanced condition of muscle tonus expresses itself in unusual postures of the resting insects, and in movements in forced paths—circus motions when one eye has been blackened. These reactions vary directly with the intensity of the illumination, as shown not only by the variation in diameters of the circles, but also by the reactions of the insects on vertical surfaces and on the turntable. The relation of the results of these experiments to the problem of heliotropic orientation is too obvious to require detailed discussion, which could only lead to a repetition of the description of the mechanism f heliotropism which Loeb has so clearly expounded. The experiments are so completely in accordance with Loeb's muscle tension theory of heliotropism, that they are tantamount to a complete proof of it.

Developmental biodynamics: the development of coordination in children

2013 ◽  
Author(s):  
James Watkins
Keyword(s):  
External Environment ◽  
Human Movement ◽  
The Body ◽  
Physical Contact ◽  
Developmental Biomechanics ◽  
Internal Forces ◽  
Muscle Groups ◽  
The Individual ◽  
External Forces ◽  
The Relationship

Human movement is brought about by the musculoskeletal system under the control of the nervous system. By coordinated activity between the various muscle groups, forces generated by the muscles are transmitted by the bones and joints to enable the individual to maintain an upright or partially upright posture and bring about voluntary controlled movements. Biomechanics of human movement is the study of the relationship between the external forces (due to body weight and physical contact with the external environment) and internal forces (active forces generated by muscles and passive forces exerted on other structures) that act on the body and the eff ect of these forces on the movement of the body. This chapter specifically addresses developmental biomechanics as it relates to the development of coordination in children.

Effects of body position on the ventilatory response following an impulse exercise in humans

2002 ◽  
Vol 92 (4) ◽  
pp. 1423-1433 ◽  
Author(s):  
Philippe Haouzi ◽  
Bruno Chenuel ◽  
Bernard Chalon
Keyword(s):  
Ventilatory Response ◽  
Body Position ◽  
Work Rate ◽  
The Body ◽  
Cardiac Transplant ◽  
Transplant Patients ◽  
Leg Exercise ◽  
Muscle Groups ◽  
Response To Exercise ◽  
The Relationship

The aim of this study was to identify some of the mechanisms that could be involved in blunted ventilatory response (V˙e) to exercise in the supine (S) position. The contribution of the recruitment of different muscle groups, the activity of the cardiac mechanoreceptors, the level of arterial baroreceptor stimulation, and the hemodynamic effects of gravity on the exercising muscles was analyzed during upright (U) and S exercise. Delayed rise in V˙e and pulmonary gas exchange following an impulselike change in work rate (supramaximal leg cycling at 240 W for 12 s) was measured in seven healthy subjects and six heart transplant patients both in U and S positions. This approach allows study of the relationship between the rise inV˙e and O2 uptake (V˙o 2) without the confounding effects of contractions of different muscle groups. These responses were compared with those triggered by an impulselike change in work rate produced by the arms, which were positioned at the same level as the heart in S and U positions to separate effects of gravity on postexercising muscles from those on the rest of the body. Despite superimposableV˙o 2 and CO2 output responses, the delayed V˙e response after leg exercise was significantly lower in the S posture than in the U position for each control subject and cardiac-transplant patient (−2.58 ± 0.44 l and −3.52 ± 1.11 l/min, respectively). In contrast, when impulse exercise was performed with the arms, reduction of ventilatory response in the S posture reached, at best, one-third of the deficit after leg exercise and was always associated with a reduction inV˙o 2 of a similar magnitude. We concluded that reduction in V˙e response to exercise in the S position is independent of the types (groups) of muscles recruited and is not critically dependent on afferent signals originating from the heart but seems to rely on some of the effects of gravity on postexercising muscles.

scholarly journals Modern approaches to the development of motor function in younger schoolchildren with postural disorders

2020 ◽  
pp. 47-50
Author(s):  
V. Lukiianchuk
Keyword(s):  
Primary School ◽  
Motor Function ◽  
Motor Skills ◽  
Muscle Tension ◽  
The Body ◽  
Necessary Condition ◽  
School Age ◽  
Muscle Groups ◽  
Primary School Age ◽  
Postural Disorders

The article identifies the causes of deviations in the development of posture in children of primary school age and characterizes the influence of this pathology on the health and physical development of schoolchildren. The necessity of development of coordination of movements in children of 6-10 years old, as well as its role in the formation of posture, prevention and correction of its defects has been substantiated. The modern approaches to the development of the motor function of schoolchildren with postural disorders are disclosed. The specificity of the action of physical exercises for the formation of the correct motor stereotype of the posture of students is highlighted, the features of the influence of dosed muscle tensions for the prevention and correction of the posture of younger students are characterized. During primary school age it is important to form the correct posture, prevent and prevent various deformities of the spine, as well as the use of dosed muscle tension and skills to maintain physiologically correct torso position in the sagittal plane and symmetrical spine position in the front to eliminate deviations in posture development at the initial stages of the ir appearance. The degree of development and opportunities for improvement of the motor sphere of children is limited by the presence of disorders of the functional activity of sensory and physiological systems of the body, including disorders of the musculoskeletal system, which include deviations in posture development. Lag in the development of motor skills of children increases the risk of forming an incorrect motor stereotype of posture and vice versa, in children with deviations in posture development there is a complication of motor skills, insufficient development of certain muscle groups, impaired balance, coordination. There are no medical contraindications to exercise in children of primary school age with postural disorders. Formation of motor function of junior schoolchildren with posture disorders involves the use of dosed exercise for the development of musculoskeletal sensitivity, development of rational flexibility of the spine, strengthening muscle groups of the muscular corset, normalization of torso muscle tone, taking into account the type of posture disorder. The development of coordination of movements of junior schoolchildren is a necessary condition for consolidating physiologically correct tors o positions while maintaining a stable posture and movement.

Relationship between Emotions and Muscle Tension in Oro-Alimentary Behavior

1985 ◽  
Vol 60 (1) ◽  
pp. 75-79 ◽  
Author(s):  
Vezio Ruggieri ◽  
Nicoletta Sabatini ◽  
Geltrude Muglia
Keyword(s):  
Muscle Tension ◽  
The Body ◽  
Direct Relation ◽  
Aggressive Behaviors ◽  
Left Half ◽  
Muscular Tension ◽  
Alimentary Behavior ◽  
The Right ◽  
The Relationship ◽  
Female Subjects

The relationship between muscular tension in the right and left masseter and orbicularis oris and different forms of hostility measured through the Gottschalk test was examined for 24 female subjects. For the muscles of the right half of the body a direct relation was noted with overt outward hostility, while on the left half of the body only the tension of the masseter was related directly to ambivalent hostility. Our hypothesis about a link between modulation of aggressive behaviors and muscles involved in functions such as chewing and biting was confirmed.

Myoelectric Activity Differences in Three Learning Sessions

2002 ◽  
Vol 16 (2) ◽  
pp. 92-96
Author(s):  
Tiina Ritvanen ◽  
Reijo Koskelo ◽  
Osmo H„nninen
Keyword(s):  
High School Students ◽  
Muscle Activity ◽  
Muscle Tension ◽  
Emg Activity ◽  
Traditional Learning ◽  
Myoelectric Activity ◽  
School Students ◽  
Language Laboratory ◽  
Upper Trapezius ◽  
Muscle Groups

Abstract This study follows muscle activity in three different learning sessions (computer, language laboratory, and normal classroom) while students were studying foreign languages. Myoelectric activity was measured in 21 high school students (10 girls, 11 boys, age range 17-20 years) by surface electromyography (sEMG) from the upper trapezius and frontalis muscles during three 45-min sessions. Root mean square (RMS) average from both investigated muscles was calculated. The EMG activity was highest in both muscle groups in the computer-aided session and lowest in the language laboratory. The girls had higher EMG activity in both investigated muscle groups in all three learning situations. The measured blood pressure was highest at the beginning of the sessions, decreased within 10 min, but increased again toward the end of the sessions. Our results indicate that the use of a computer as a teaching-aid evokes more constant muscle activity than the traditional learning situations. Since muscle tension can have adverse health consequences, more research is needed to determine optimal classroom conditions, especially when technical aids are used in teaching.

The use of Body Surface Index as a Better Clinical Health indicators Compare to Body Mass Index and Body Surface Area for Clinical Application

2018 ◽  
pp. 131-136
Author(s):  
Shirazu I. ◽  
Theophilus. A. Sackey ◽  
Elvis K. Tiburu ◽  
Mensah Y. B. ◽  
Forson A.
Keyword(s):  
Surface Area ◽  
Body Surface Area ◽  
Clinical Application ◽  
Body Surface ◽  
Body Height ◽  
Health Indicators ◽  
The Body ◽  
Body Parameters ◽  
The Relationship ◽  
Individual Body

The relationship between body height and body weight has been described by using various terms. Notable among them is the body mass index, body surface area, body shape index and body surface index. In clinical setting the first descriptive parameter is the BMI scale, which provides information about whether an individual body weight is proportionate to the body height. Since the development of BMI, two other body parameters have been developed in an attempt to determine the relationship between body height and weight. These are the body surface area (BSA) and body surface index (BSI). Generally, these body parameters are described as clinical health indicators that described how healthy an individual body response to the other internal organs. The aim of the study is to discuss the use of BSI as a better clinical health indicator for preclinical assessment of body-organ/tissue relationship. Hence organ health condition as against other body composition. In addition the study is `also to determine the best body parameter the best predict other parameters for clinical application. The model parameters are presented as; modeled height and weight; modelled BSI and BSA, BSI and BMI and modeled BSA and BMI. The models are presented as clinical application software for comfortable working process and designed as GUI and CAD for use in clinical application.

CONCEPTUALISING RISK CULTURE ON ERM IMPLEMENTATION IN CONSTRUCTION COMPANIES

2020 ◽  
Vol 17 (1) ◽  
pp. 59
Author(s):  
Ching Ching Wong
Keyword(s):  
Risk Management ◽  
Risk Identification ◽  
The Body ◽  
Risk Indicators ◽  
Construction Companies ◽  
Risk Appetite ◽  
Risk Culture ◽  
Risk Treatment ◽  
Managing Risk ◽  
The Relationship

Enterprise Risk Management (ERM) is an effective technique in managing risk within an organization strategically and holistically. Risk culture relates to the general awareness, attitudes and behaviours towards risk management in an organisation. This paper presents a conceptual model that shows the relationship between risk culture and ERM implementation. The dependent variable is ERM implementation, which is measured by the four processes namely risk identification and risk assessment; risk treatment; monitor and consult; communicate and consult. The independent variables under risk culture are risk policy and risk appetite; key risk indicators; accountability; incentives; risk language and internal relationships. This study aims to empirically test the relationship between risk culture and ERM implementation among Malaysian construction public listed companies. Risk culture is expected to have direct effects and significantly influence ERM. This study contributes to enhance the body of knowledge in ERM especially in understanding significant of risk culture that influence its’ implementation from Malaysian perspective.

Structural Mediation Model of Information System and Sustainable Performance of UAE Manufacturing Sector

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Mohamed Ahmed Darwish Abdulla Larii ◽  
◽  
Fatma Ahmed Lari ◽  
Mohamed Ahmed Darwish Abdulla Lari ◽  
◽  
...  
Keyword(s):  
Information System ◽  
Manufacturing Sector ◽  
Organisational Culture ◽  
The Body ◽  
Mediating Effect ◽  
Operational Performance ◽  
Manufacturing Companies ◽  
Mediation Model ◽  
Sustainable Performance ◽  
The Relationship

This study intends to find out the mediating effect of organisational culture on the relationship between information system and sustainable performance of manufacturing sector in UAE. This study used AMOS-SEM software to develop mediation model that linking the mediating relationships between Information System, Organisational Culture and Sustainable operation Performance. Data was collected through questionnaire survey among the operation staff of Abu Dhabi manufacturing companies. A total 250 questionnaires were distributed however 205 were returned and only 200 are valid which indicates a response rate of 80%. The analysis found that TPS has positive but not significant effect to SP; OIS has positive but not significant effect to SP; FMW has a positive and significant effect on SP; SDS has a negative and not significant effect to SP and SP has positive but not significant effect OC. For the path relationship between the four exogenous variables (TPS, OIS, SDS, and FMW) and the mediator variable (OC), the results are TPS has positive and significant effect to OC; OIS has positive but not significant effect to OC; FMW has positive and significant effect to OC and SDS has positive and not significant effect to OC. Collectively, the five exogenous constructs (TPS, OIS, SDS, FMW and OC) explained 89% variation in operational performance and 86% of the variation in organisational culture. However, for a mediator, it was found that OC has no significant mediating effect on the relationship between TPS and SP; OC has no significant mediating effect on the relationship between OIS and SP; OC has no significant mediating effect on the relationship between SDS and SP and OC has no significant mediating effect on the relationship between FMW and SP. it can be concluded that there is a positive relationship between information system dimensions and operational performance. However organizational culture has no contributing any mediating effect to the relationship. These findings have contributed to the body of knowledge and could be shared among the UAE manufacturing practitioners.

Study of the infl uence of information and communication tools on the psychophysiological state of schoolchildren on the basis of subjective evaluation

2020 ◽  
pp. 47-55
Author(s):  
Aleksandra Rakhmanova ◽  
Georgiy Loginov ◽  
Vladimir Dolich ◽  
Nataliya Komleva ◽  
Galina Rakhmanova
Keyword(s):  
High School ◽  
Emotional State ◽  
Statistical Significance ◽  
Subjective Evaluation ◽  
Educational Process ◽  
The Body ◽  
Leningrad Region ◽  
Communication Tools ◽  
Information And Communication ◽  
The Relationship

The relevance of the article is determined by the existence of contradictions between the need to introduce innovative technologies into the educational process at school, as an integral attribute of modern education, and the negative influence of factors on the physical and psycho-emotional state of health of students related to the use of information and communication tools (computers, phones, headphones). The goal of the study was to assess the relationship between the timing of the use of information and communication tools and the frequency of functional and psycho-emotional complaints in groups of middle and high school schoolchildren. 400 schoolchildren of the Saratov Region, the Moscow Region, Leningrad Region and the Republic of Dagestan were surveyed, who made up two groups of research: middle-school schoolchildren (grades 5–6) and high-school schoolchildren (grades 10–11 The survey was carried out by means of the standardized formalized cards which included the questions considering usage time of computers and mobile phones, complaints to a headache, hands pain, other pain and/or feeling of discomfort from visual organ and the organs of hearing, as well as a psycho-emotional state. Statistical analysis of the data was performed using the STATISTICA application software program by StatSoft Inc (USA). To compare the frequencies of a binary feature, a fourfold table of absolute frequencies was constructed and the level of statistical significance for the exact Fisher’s two-tailed test criterion was determined. The study was conducted according to the requirements of bioethics, after signing informed consent statement by teenagers and their parents. The study examined the relationship between the timing of the use of information and communication tools and the frequency of complaints in groups of schoolchildren. The results of the study should be taken into account when developing and implementing preventive measures to prevent negative effects of computers and mobile devices on the body of students.

EXPERIMENTAL ASSESSMENT OF THE NANOPARTICLES TOXICITY OF NICKEL OXIDE IN TWO SIZES IN THE SUBCHRONIC EXPERIMENT

2018 ◽  
pp. 30-35
Author(s):  
M.P. Sutunkova ◽  
B.A. Katsnelson ◽  
L.I. Privalova ◽  
S.N. Solovjeva ◽  
V.B. Gurvich ◽  
...  
Keyword(s):  
Nickel Oxide ◽  
Nervous Activity ◽  
Equal Mass ◽  
The Body ◽  
Subchronic Toxicity ◽  
Physiological Mechanisms ◽  
Nickel Oxide Nanoparticles ◽  
The Relationship ◽  
The Brain ◽  
Nanoparticles Toxicity

We conducted a comparative assessment of the nickel oxide nanoparticles toxicity (NiO) of two sizes (11 and 25 nm) according to a number of indicators of the body state after repeated intraperitoneal injections of these particles suspensions. At equal mass doses, NiO nanoparticles have been found to cause various manifestations of systemic subchronic toxicity with a particularly pronounced effect on liver, kidney function, the body’s antioxidant system, lipid metabolism, white and red blood, redox metabolism, spleen damage, and some disorders of nervous activity allegedly related to the possibility of nickel penetration into the brain from the blood. The relationship between the diameter and toxicity of particles is ambiguous, which may be due to differences in toxicokinetics, which is controlled by both physiological mechanisms and direct penetration of nanoparticles through biological barriers and, finally, unequal solubility.

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