scholarly journals THE GILL MOVEMENTS OF NYMPHAL ECDYONURUS VENOSUS (EPHEMEROPTERA) AND THE CURRENTS PRODUCED BY THEM IN WATER

1937 ◽  
Vol 14 (2) ◽  
pp. 219-228 ◽  
Author(s):  
L. E. S. EASTHAM
Keyword(s):  
Environmental Flow ◽  
The Body ◽  
Angle Of Incidence ◽  
Sense Organs ◽  
Anterior Border ◽  
Compression Phase ◽  
Recovery Movement ◽  
Leading Position ◽  
Effective Part ◽  
Set Up

1. The gills of the nymph of Ecdyonurus consist each of a gill plate and a proximal gill tuft. The gill plate of the first gill is reduced in size while the seventh gill possesses no gill tuft. 2. By movements of the gills, currents are set up in the water which are symmetrical with the body axis, and which pass from the sides of the body upwards to the mid-dorsal line and backwards. Members of pairs beat synchronously and in phase with each other. 3. Each gill pivots on its pedicel and moving backwards and upwards, increases its angle of incidence with the water through which it passes. This phase is the effective part of an oscillation and is brought about with the posterior gill surface in the leading position. The recovery beat is effected by the gill turning so as to place the anterior border in a leading position. The direction of flow is largely determined by these gill movements. 4. The gills beat in metachronal rhythm from before backwards, the time phase difference between adjacent gills being so small as to make the gills appear to work together and without rhythm. The rhythm, however, is important in setting up suction and compression phases, the compression phase occurring during backward effective movement, the suction during forward recovery movement. Compression expresses itself as a flow from between the gills upwards and backwards, suction as a flow into the intergill space from the sides and below. 5. The principles of gill movement in relation to water flow in Caenis, Leptophlebia and Ecdyonurus are compared. 6. The currents and gill movements in adaptation to environment are briefly discussed. 7. Campaniform sense organs occur on both surfaces of the gill plates and it is suggested that these are concerned with informing the animal of changes in the environmental flow of water.

scholarly journals Gill Movements of Nymphal Ephemera danica (Ephemeroptera) and the Water Currents caused by them

1939 ◽  
Vol 16 (1) ◽  
pp. 18-33 ◽  
Author(s):  
L. E. S. EASTHAM
Keyword(s):  
Transverse Force ◽  
The Body ◽  
Body Axis ◽  
Angle Of Incidence ◽  
Middle Line ◽  
Water Currents ◽  
The Difference ◽  
Force Components ◽  
Set Up ◽  
Ephemera Danica

1. The six pairs of gills in Ephemera danica causing currents in the water are bilamellate and feather-like. 2. The gills move in metachronal rhythm from before backwards, and set up currents which are symmetrical with the body axis. Members of pairs of gills beat synchronously and in phase with each other. The difference of phase between two adjacent gills of the same side is about one-eighth of a complete oscillation. 3. For a single gill there is little or no difference in the angle presented by the gill to its own path of motion, in the two halves of an oscillation. This factor (angle of incidence) is not of great importance in directing water backwards. Forces of importance in moving water in the direction taken are (i) the resultant of axial and transverse force components for single gills, (ii) the pressure effected on the water over the animal's back by the two members of a pair of gills falling, (iii) the movement backwards of alternating pressure regions over the back, (iv) the undulations of the second screw-like gills which feed the main current from in front and from the sides. 4. The fringing filaments of adjacent gills overlap each other from before backwards (as seen from the middle line of the body), and thus each row of gills forms a "membrane" composed of separate gill units. The latter appear never to lose contact with each other during movement, and since no sideways flow is observed between the gills it is assumed that the overlapping filaments between the gills form a membrane impermeable to flow. 5. The adaptation of Ephemera to its sandy environment is shortly discussed.

Osteopathic support of sportsmen during the annual training process

2020 ◽  
pp. 37-43 ◽  
Author(s):  
R. A. Yakupov ◽  
G. I. Safiullina ◽  
A. A. Safiullina ◽  
E. R. Burganov
Keyword(s):  
Musculoskeletal Diseases ◽  
Muscle Tone ◽  
The Body ◽  
Training Process ◽  
Health Maintenance ◽  
Osteopathic Treatment ◽  
Leading Position ◽  
Myofascial Syndrome ◽  
Sports Activities ◽  
Timely Treatment

Introduction. Modern sports places high demands on the functional systems of the body at all stages of the training and competitive processes. High loads create signifi cant background for the occurrence of musculoskeletal diseases, among which the myofascial syndrome (MFS) holds the leading position. MFS negatively affects the functional readiness of the sportsman′s body and is a risk factor for injuries of the musculoskeletal system. In this regard, timely treatment of MFS is important. It creates the conditions for the improvement of sports achievements, for health maintenance and sports longevity. Treatment of patients with MFS should include methods that normalize trophism and muscle tone. Given the problem of doping, the use of non-drug methods, including osteopathy, is preferable. The goal of research — to develop a system of monitoring and osteopathic correction of myofascial disorders (MFD) and to introduce it into the practice of medical and biological support for sportsmen of different categories and levels during the annual training process.Materials and methods. 93 sportsmen (45 women and 48 men), mean age 22,1±1,1 years, representing diffe rent sports were examined. The essence of the proposed system is regular clinical and electroneurophysiological monitoring of the body condition and preventive correction of myofascial disorders in order to exclude their infl uence on the success of sports activities.Results. It was established that the proposed system of monitoring and osteopathic correction led to a signifi cant reduction in clinical and electroneurophysiological manifestations both in local and in extensive forms of myofascial disorders, which allowed to maintain the optimal functional readiness of sportsmen throughout the entire annual training cycle.Conclusion. The system of monitoring and correction of MFS with the use of osteopathic treatment can be one of the elements of medical and biological support for sportsmen during the annual training process.

Set up and management of a Data Science faculty at Shiga University

Impact ◽  
2019 ◽  
Vol 2019 (10) ◽  
pp. 18-20
Author(s):  
Akimichi Takemura
Keyword(s):  
Data Science ◽  
Science Faculty ◽  
Knowledge And Skills ◽  
International Trends ◽  
Leading Position ◽  
Global Understanding ◽  
Set Up ◽  
The University ◽  
Do So ◽  
Undergraduate Class

Shiga University opened the first data science faculty in Japan in April 2017. Beginning with an undergraduate class of 100 students, the Department has since established a Master's degree programme with 20 students in each annual intake. This is the first data science faculty in Japan and the University intends to retain this leading position, the Department is well-placed to do so. The faculty closely monitors international trends concerning data science and Artificial Intelligence (AI) and adapt its education and research accordingly. The genesis of this department marks a change in Japan's attitudes towards dealing with information and reflects a wider, global understanding of the need for further research in this area. Shiga University's Data Science department seeks to produce well-trained data scientists who demonstrate a good balance of knowledge and skills in each of the three key areas of data science.

Two-dimensional scattering of a plane compressional wave by surface imperfections

1969 ◽  
Vol 59 (3) ◽  
pp. 1349-1364
Author(s):  
Ivor K. McIvor
Keyword(s):  
Order Approximation ◽  
Strong Dependence ◽  
Plane Waves ◽  
Compressional Wave ◽  
Elastic Half Space ◽  
Kernel Functions ◽  
The Body ◽  
Angle Of Incidence ◽  
Small Surface ◽  
Surface Imperfections

abstract A perturbation method for treating the scattering of plane waves by small surface imperfections on an elastic half space is presented. The solution to the first order approximation is given as convolution integrals of the surface imperfection with kernel functions defined by Fourier inversion integrals. The evaluation of these integrals is discussed and their asymptotic representations determined. The far field scattered displacements are explicitly obtained for arbitrary imperfections. The scattered field consists of a Rayleigh surface wave and four body phases which at the free surface travel with the speed of dilational or distortional waves. Numerical examples are given. In particular the error in the apparent angle of emergence due to the scattered waves is obtained. The body phases exhibit the familiar 3/2 geometric attenuation, but still may make a significant contribution at moderately long distances. A strong dependence of the magnitude of the error on the angle of incidence is demonstrated.

External work in level and grade walking on a motor-driven treadmill

1960 ◽  
Vol 15 (5) ◽  
pp. 759-763 ◽  
Author(s):  
J. W. Snellen
Keyword(s):  
Heat Loss ◽  
Heat Production ◽  
Total Energy Expenditure ◽  
The Body ◽  
External Work ◽  
Thermal Exchange ◽  
Level Walking ◽  
The Subject ◽  
Set Up ◽  
Physical Laws

When studying a walking subject's thermal exchange with the environment, it is essential to know whether in level walking any part of the total energy expenditure is converted into external mechanical work and whether in grade walking the amount of the external work is predictable from physical laws. For this purpose an experiment was set up in which a subject walked on a motor-driven treadmill in a climatic room. In each series of measurements a subject walked uphill for 3 hours and on the level for another hour. Metabolism was kept equal in both situations. Air and wall temperatures were adjusted to the observed weighted skin temperature in order to avoid any heat exchange by radiation and convection. Heat loss by evaporation was derived from the weight loss of the subject. All measurements were carried out in a state of thermal equilibrium. In grade walking there was a difference between heat production and heat loss by evaporation. This difference equaled the caloric equivalent of the product of body weight and gained height. In level walking the heat production equaled heat loss. Hence it was concluded that in level walking all the energy is converted into heat inside the body. Submitted on April 26, 1960

On one-dimensional unsteady flow at infinite Mach number

1968 ◽  
Vol 304 (1478) ◽  
pp. 255-273 ◽  
Keyword(s):  
Asymptotic Expansion ◽  
Blast Wave ◽  
Outer Part ◽  
The Body ◽  
Viscous Boundary Layer ◽  
Outer Flow ◽  
Hypersonic Speeds ◽  
Set Up ◽  
Viscous Boundary ◽  
Infinite Set

The use of the blast-wave analogy, as an aid to the interpretation of experimental data on the motion of a fluid past an obstacle at hypersonic speeds, has led to the theoretical study of its role in an asymptotic expansion of the solution to the governing equations at large distances downstream of the body. In all attempts to set up such an expansion it has proved necessary to divide the flow régime into two parts, an outer part dominated by the blast wave and an inner part consisting of streamlines which, originally, pass close by the body. The matching of these two regions is apparently only possible if a certain integral vanishes. In the present paper a numerical integration, in one particular set of circumstances, is carried out to test the validity of the asymptotic expansion proposed. Formally, an unsteady problem is tackled, for ease of computation, but the steady analogue follows immediately and is of exactly the form discussed in the earlier investigations. It is found that the main results are in line with the theory and that the integral in question is indistinguishable from zero. However, a deeper investigation of the asymptotic expansion shows that, for an expansion of the type envisaged, an infinite set of integrals must each vanish. The next integral does not appear to be zero according to our computations but this result is not believed to be conclusive. Assuming that all the integrals do vanish, then it appears that the inner layer, which although inviscid, has many of the characteristics of a viscous boundary layer, has the addi­tional, surprising property that it can exert no direct influence on the outer flow at large distances downstream of the body.

scholarly journals Weavers & Warriors? Gender and Online Identity in 1997 and 2007 V1.0

2008 ◽  
Vol 2 (2) ◽  
Author(s):  
Deirdre Ruane
Keyword(s):  
Preliminary Investigation ◽  
The Body ◽  
Internet Technology ◽  
Online Identity ◽  
Men And Women ◽  
Online Interactions ◽  
And Performance ◽  
And Gender ◽  
Set Up ◽  
Active Exploration

In 1997 the Internet was seen by many as a tool for radical reinterpretation of physicality and gender. Cybertheorists predicted we would leave our bodies behind and interact online as disembodied minds, and that the technology would reshape the way we saw ourselves. However, physicality has proved to be an inextricable part of all our interactions. Changing Internet technology has allowed Net users to find a myriad ways to perform and express their gender online. In this paper I consider attitudes to gender on the Net in 1997, when the main concerns were the imbalance between men and women online and whether it was possible or desirable to bring the body into online interactions. In much of the discourse surrounding gender online, a simple binary was assumed to exist. I go on to consider the extent to which those attitudes have changed today. Through my own experience of setting up a women’s community on Livejournal, and my observations of a men’s community set up in response, I conclude that though traditional attitudes to gender have largely translated to the Net and the binary is still the default view, some shifts have occurred. For example, between 1997 and today there seems to have been a fundamental change in perceptions of women’s attitudes to adversarial debate, and an increase in awareness of genders beyond the binary. In addition, experience and preliminary investigation lead me toward a hypothesis that today’s female-identified Net users are engaged in more conscious and active exploration and performance of their gender online than male-identified users are.

scholarly journals The Latest Progress and Development Trend in the Research of Ballistocardiography (BCG) and Seismocardiogram (SCG) in the Field of Health Care

2021 ◽  
Vol 11 (19) ◽  
pp. 8896
Author(s):  
Xiuping Han ◽  
Xiaofei Wu ◽  
Jiadong Wang ◽  
Hongwen Li ◽  
Kaimin Cao ◽  
...  
Keyword(s):  
Health Care ◽  
Health Assessment ◽  
Development Trend ◽  
Developed Countries ◽  
Current Status ◽  
Research Subjects ◽  
Leading Position ◽  
Important Direction ◽  
Set Up ◽  
The Developed Countries

The current status of the research of Ballistocardiography (BCG) and Seismocardiogram (SCG) in the field of medical treatment, health care and nursing was analyzed systematically, and the important direction in the research was explored, to provide reference for the relevant researches. This study, based on two large databases, CNKI and PubMed, used the bibliometric analysis method to review the existing documents in the past 20 years, and made analyses on the literature of BCG and SCG for their annual changes, main countries/regions, types of research, frequently-used subject words, and important research subjects. The results show that the developed countries have taken a leading position in the researches in this field, and have made breakthroughs in some subjects, but their research results have been mainly gained in the area of research and development of the technologies, and very few have been actually industrialized into commodities. This means that in the future the researchers should focus on the transformation of BCG and SCG technologies into commercialized products, and set up quantitative health assessment models, so as to become the daily tools for people to monitor their health status and manage their own health, and as the main approaches of improving the quality of life and preventing diseases for individuals.

Theorising love in sociological thought: Classical contributions to a sociology of love

2017 ◽  
Vol 18 (1) ◽  
pp. 3-20 ◽  
Author(s):  
Mihai Stelian Rusu
Keyword(s):  
Nuclear Family ◽  
Social World ◽  
The Body ◽  
Talcott Parsons ◽  
Sociological Tradition ◽  
Binding Force ◽  
Social Nature ◽  
External Pressures ◽  
The Social ◽  
Set Up

This article sets out to explore the contributions of classical social thinkers to a sociological understanding of love. It builds on the premise that despite its major relevance and consequential importance in shaping both individual lives and the social world, until recently love was a heavily undertheorised topic in the sociological tradition. Moreover, the body of disparate sociological reflections that have been made on the social nature of love has been largely forgotten in the discipline’s intellectual legacy. The article then proceeds in unearthing the classics’ contributions to a sociology of love. It starts with Max Weber’s view that love promises to be a means of sensual salvation in an increasingly rationalised social world based on impersonal formal relationships. Next, it critically examines Pitirim A. Sorokin’s integral theory of love. It then moves to address Talcott Parsons’ view on love as a binding force whose social function is to integrate the conjugal couple of the modern nuclear family in the absence of the external pressures exerted by the kinship network. The article concludes by showing how these conceptualisations of love were all embedded in wider theoretical constructions set up to account for the modernisation process.

The Activity of Lateral-Line Efferent Neurones in Stationary and Swimming Dogfish

1972 ◽  
Vol 57 (2) ◽  
pp. 435-448 ◽  
Author(s):  
B. L. ROBERTS ◽  
I. J. RUSSELL
Keyword(s):  
Lateral Line ◽  
Body Movement ◽  
Cranial Nerves ◽  
Regulatory System ◽  
The Body ◽  
Muscle Fibres ◽  
Sense Organs ◽  
Efferent System ◽  
Natural Stimulation ◽  
Stimulation Of

1. The activity of efferent neurones innervating lateral-line organs on the body of dogfish was followed by recording from filaments of cranial nerve X in 41 decerebrate preparations. 2. The efferent nerves were not spontaneously active. 3. Tactile stimulation to the head and body, vestibular stimulation and noxious chemical stimulation were followed by activity of the efferent nerves. 4. In contrast, natural stimulation of lateral-line organs (water jets) did not reflexly evoke discharges from the efferent fibres. 5. Reflex efferent responses were still obtained to mechanical stimulation even after the lateral-line organs had been denervated. 6. Electrical stimulation of cranial nerves innervating lateral-lines organs was followed by reflex activity of the efferent fibres. But similar stimuli applied to other cranial nerves were equally effective in exciting the efferent system. 7. Vigorous movements of the fish, involving the white musculature, were preceded and accompanied by activity of the efferent fibres which persisted as long as the white muscle fibres were contracting. 8. Rhythmical swimming movements were accompanied by a few impulses in the efferent fibres grouped in bursts at the same frequency as the swimming movements. 9. It is concluded that the efferent neurones cannot contribute to a feedback regulatory system because they are not excited by natural stimulation of the lateral-line sense organs. The close correlation found between efferent activity and body movement suggests that the efferent system might operate in a protective manner to prevent the sense organs from being over-stimulated when the fish makes vigorous movements.

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