RELATION BETWEEN THE AMOUNT OF CATALASE IN THE DIFFERENT MUSCLES OF THE BODY AND THE AMOUNT OF WORK DONE BY THESE MUSCLES

1916 ◽  
Vol 41 (2) ◽  
pp. 153-161 ◽  
Author(s):  
W. E. Burge
Keyword(s):  
The Body ◽  
Work Done

Quantum superposition of massive bodies

2020 ◽  
Vol 29 (11) ◽  
pp. 2041003
Author(s):  
Robert M. Wald
Keyword(s):  
Gravitational Field ◽  
Gravitational Radiation ◽  
The Body ◽  
Vacuum Fluctuations ◽  
Quantum Superposition ◽  
Gedanken Experiment ◽  
Work Done

I describe the work done in collaboration with A. Belenchia, F. Giacomini, E. Castro-Ruiz, C. Bruckner and M. Aspelmeyer that analyzes a gedanken experiment involving a massive body that is put into a quantum superposition. Remarkably, even for a nonrelativistic body, both vacuum fluctuations of the gravitational field and the quantization of gravitational radiation are essential in order to avoid inconsistencies. In addition, it is essential that the quantum body be viewed as entangled with its own Newtonian-like gravitational field in order to understand how the body may become entangled with other massive bodies via gravitational interactions.

External work in walking

1963 ◽  
Vol 18 (1) ◽  
pp. 1-9 ◽  
Author(s):  
G. A. Cavagna ◽  
F. P. Saibene ◽  
R. Margaria
Keyword(s):  
Inertial Force ◽  
Center Of Gravity ◽  
The Body ◽  
External Work ◽  
High Speeds ◽  
Moving Body ◽  
Vertical Displacements ◽  
Lateral Displacements ◽  
Work Done ◽  
Static Contractions

From records obtained from a triple accelerometer applied to the trunk of a subject the displacements of the trunk in vertical, forward, and lateral directions have been calculated. With motion pictures taken simultaneously, displacements of the center of gravity within the body were measured. From these data the external mechanical work of walking was calculated. The sum of work for vertical and for forward displacements of the center of gravity of the body gives the total external work; energy for the lateral displacements was negligible. Total external work appears to be lower than that calculated from the vertical displacements alone, because work done in lifting is partly sustained by the inertial force of the forward-moving body. Total external work reaches a highest value (0.1 kcal/km kg) at the most economical speed of walking, 4 km/hr, which corresponds to an energy consumption of 0.48 kcal/km kg. At this speed the internal work appears negligible; it amounts to appreciable entities at very low speeds because of the static contractions of the muscles, and at high speeds because of considerable stiffening of the limbs and movements not involving a displacement of the center of gravity. Submitted on May 25, 1962

The energy distribution resulting from an impact on a floating body

2000 ◽  
Vol 417 ◽  
pp. 157-181 ◽  
Author(s):  
A. A. KOROBKIN ◽  
D. H. PEREGRINE
Keyword(s):  
Kinetic Energy ◽  
Energy Distribution ◽  
Water Flow ◽  
Compression Wave ◽  
The Body ◽  
The Other ◽  
Body Motion ◽  
Floating Body ◽  
Pressure Impulse ◽  
Work Done

The initial stage of the water flow caused by an impact on a floating body is considered. The vertical velocity of the body is prescribed and kept constant after a short acceleration stage. The present study demonstrates that impact on a floating and non-flared body gives acoustic effects that are localized in time behind the front of the compression wave generated at the moment of impact and are of major significance for explaining the energy distribution throughout the water, but their contribution to the flow pattern near the body decays with time. We analyse the dependence on the body acceleration of both the water flow and the energy distribution – temporal and spatial. Calculations are performed for a half-submerged sphere within the framework of the acoustic approximation. It is shown that the pressure impulse and the total impulse of the flow are independent of the history of the body motion and are readily found from pressure-impulse theory. On the other hand, the work done to oppose the pressure force, the internal energy of the water and its kinetic energy are essentially dependent on details of the body motion during the acceleration stage. The main parameter is the ratio of the time scale for the acoustic effects and the duration of the acceleration stage. When this parameter is small the work done to accelerate the body is minimal and is spent mostly on the kinetic energy of the flow. When the sphere is impulsively started to a constant velocity (the parameter is infinitely large), the work takes its maximum value: Longhorn (1952) discovered that half of this work goes to the kinetic energy of the flow near the body and the other half is taken away with the compression wave. However, the work required to accelerate the body decreases rapidly as the duration of the acceleration stage increases. The optimal acceleration of the sphere, which minimizes the acoustic energy, is determined for a given duration of the acceleration stage. Roughly speaking, the optimal acceleration is a combination of both sudden changes of the sphere velocity and uniform acceleration.If only the initial velocity of the body is prescribed and it then moves freely under the influence of the pressure, the fraction of the energy lost in acoustic waves depends only on the ratio of the body's mass to the mass of water displaced by the hemisphere.

scholarly journals Desain dan Pengujian Alat Tanam Benih Jagung

2017 ◽  
Vol 2 (1) ◽  
pp. 314-319
Author(s):  
Muhammad Iskandar ◽  
Mustaqimah Mustaqimah ◽  
Syafriandi Syafriandi
Keyword(s):  
Ground Surface ◽  
Soil Surface ◽  
Data Retrieval ◽  
The Body ◽  
Original Position ◽  
Working Capacity ◽  
Planting Depth ◽  
Testing Tools ◽  
Long Time ◽  
Work Done

Abstrak. Alat tanam merupakan suatu alat yang digunakan untuk menempatkan benih tanaman yaitu biji-bijian, bibit, batang atau sebagian tubuh tanaman lain diatas atau dibawah permukaan tanah. Alat tanam didesain memiliki fungsi untuk mempercepat proses penanaman pada lahan jagung dan mempermudah serta tidak memakan waktu yang lama. Tugal ini diharapkan mampu mengatasi permasalahan perkebunan yaitu keterbatasan waktu. Cara kerja tugal penanam jagung semi  mekanis menggunakan pegas pada saat  mata tugal  masuk ke dalam tanah. Pengatur pengeluaran benih tertekan  keatas oleh permukaan tanah. Kemudian mendorong tangkai pegas,  sehingga  lubang  benih  terbuka  dan  benih  pun  terjatuh  ke  bawah yang dibuat oleh mata tugal. Selanjutnya pada saat tugal diangkat dari permukaan tanah, tugal kembali pada posisi semula karena kerja dari pegas.Pengujian kapasitas kerja tugal semi mekanis ditentukan dengan kecepatan penanaman. Pada pengujian ini untuk jarak benih perbaris menggunakan jarak yang umum digunakan yaitu 50 cm. Pengambilan data kecepatan kerja alat dilakukan sebanyak 3 kali pengulangan pada jarak 17 meter. Dengan asumsi sepanjang 17 meter bila jarak antar benih tiap baris 50 cm maka sebanyak 36 lubang tanam. Dari hasil perhitungan kapasitas kerja tugal penanam ini yaitu 0.02 ha/jam. Hasil kedalaman tanam pada pengulangan ke 1 kedalaman tanam benih rata-rata jatuh pada lubang tanam adalah 4,08 cm. Pada pengulangan ke 2 kedalaman tanam benih rata-rata jatuh pada lubang tanam adalah 3,94 cm. Sedangkan pada pengulangan ke 3 kedalaman tanam benih rata-rata jatuh pada lubang tanam adalah 4,05 cm. Design and Testing Tools Planting Corn SeedsAbstract. A planting tool is a tool that is used to place the seed crop is grain, seed, stem or any part of the body other plants above or below the ground surface. A planting tool designed to have a function to accelerate the process of planting the corn field and enables easy and does not take a long time. A planting tool is expected to overcome the problems of plantation that time constraints workings drill corn planter mechanically using spring when the eyes drill into the ground. Regulatory seed depressed spending upwards by the soil surface. Then push the stalk of the spring, so that the holes open seeds and seeds also fell down created by the drill eye. Furthermore, when the drill is lifted from the ground, drill back to its original position due to the work of the working capacity spring. Examination semi mechanical drill is determined by the speed of planting. In this test for distance using a distance line seeds commonly used is 50 cm. Speed data retrieval tool work done 3 times a repetition at a distance of 17 meters. Assuming a 17-meter when the distance between seeds in each row 50 cm by 36 planting holes. From the calculation of working capacity drill this planter is 0.02 ha / hour. Planting depth results on repeatability to 1 seed planting depth average on hole fall planting is 4.08 cm. on repetition to 2 seed planting depth average on hole fall planting is 3.94 cm. while at repetition to 3 seed planting depth average on hole fall planting is 4.05 cm.

Mechanical power and work of cat soleus, gastrocnemius and plantaris muscles during locomotion: possible functional significance of muscle design and force patterns.

1996 ◽  
Vol 199 (4) ◽  
pp. 801-814 ◽  
Author(s):  
B I Prilutsky ◽  
W Herzog ◽  
T L Allinger
Keyword(s):  
Electrical Activity ◽  
Mechanical Energy ◽  
Fibre Length ◽  
Rate Of Change ◽  
The Body ◽  
Mechanical Power ◽  
Step Cycle ◽  
Extensor Muscles ◽  
Work Done ◽  
Positive Work

Electrical activity, forces, power and work of the soleus (SO), the gastrocnemius (GA) and the plantaris (PL) muscles were measured during locomotion in the cat in order to study the functional role of these ankle extensor muscles. Forces and electrical activity (EMG) of the three muscles were measured using home-made force transducers and bipolar, indwelling wire electrodes, respectively, for walking and trotting at speeds of 0.4 to 1.8 m s-1 on a motor-driven treadmill. Video records and a geometrical model of the cat hindlimb were used for calculating the rates of change in lengths of the SO, GA and PL muscles. The instantaneous maximum possible force that can be produced by a muscle at a given fibre length and the rate of change in fibre length (termed contractile abilities) were estimated for each muscle throughout the step cycle. Fibre lengths of the SO, GA and PL were calculated using a planar, geometrical muscle model, measured muscle forces and kinematics, and morphological measurements from the animal after it had been killed. Mechanical power and work of SO, GA and PL were calculated for 144 step cycles. The contribution of the positive work done by the ankle extensor muscles of one hindlimb to the increase of the total mechanical energy of the body (estimated from values in the literature) increased from 4-11% at speeds of locomotion of 0.4 and 0.8 m s-1 to 7-16% at speeds of 1.2 m s-1 and above. The relative contributions of the negative and positive work to the total negative and positive work done by the three ankle extensor muscles increased for GA, decreased for SO and remained about the same for PL, with increasing speeds of locomotion. At speeds of 0.4-0.8 m s-1, the positive work normalized to muscle mass was 7.5-11.0 J kg-1, 1.9-3.0 J kg-1 and 5.3-8.4 J kg-1 for SO, GA and PL, respectively. At speeds of 1.2-1.8 m s-1, the corresponding values were 9.8-16.7 J kg-1, 6.0-10.7 J kg-1 and 13.4-25.0 J kg-1. Peak forces of GA and PL increased and peak forces of SO did not change substantially with increasing speeds of locomotion. The time of decrease of force and the time of decrease of power after peak values had been achieved were much shorter for SO than the corresponding times for GA and PL at fast speeds of locomotion. The faster decrease in the force and power of SO compared with GA and PL was caused by the fast decrease of the contractile abilities and the activation of SO. The results of this study suggest that the ankle extensor muscles play a significant role in the generation of mechanical energy for locomotion.

Plural Bodies, Pluriversal Humans: Questioning the Ontology of ‘Body’ in Design

Somatechnics ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 286-305
Author(s):  
Ahmed Ansari
Keyword(s):  
Design Research ◽  
The Body ◽  
Human Biology ◽  
Ontological Turn ◽  
Work Done ◽  
Multiple Ontologies

All designing, as well as everything designed, is ontological: things shape and form humans, just as humans shape and give form to them (Willis, 2006, Fry, 2013). However, there is no ontology of the human in the singular sense, but plural, multiple ontologies, and therefore, no human, but only humans. This paper proposes the introduction of a provocation to disturb notions of the ontologically designed body, and in fact, of how we think of what a ‘body’ is, by turning to the insights offered up by a body of literature hitherto relatively unexamined in design research: the ontological turn in anthropology. By turning to a survey of the work done by cultural anthropologists on different cosmologies and cultures, I intend to demonstrate that the Anglo-Eurocentric conception of the ontologically singular body, signified in terms of the “universality” of human biology, is in fact, only one of many ways of bodily being and relating to the body; that matters of the body are locally situated and specific to communities and environments; and therefore, what we mean by ‘the body’ is in fact also plural, multistable, and wrought with incommensurabilities between human communities and cultures. The essay will end with a re-evaluation of ontological designing and speculations on what design could do, through an engagement with examples of ‘other’ ontologies and definitions of body.

XXI. The direct influence of gradual variations of temperature upon the rate of beat of the dog’s heart

1883 ◽  
Vol 174 ◽  
pp. 663-688 ◽  
Keyword(s):  
Arterial Pressure ◽  
Pulse Rate ◽  
Venous Pressure ◽  
Practical Importance ◽  
The Body ◽  
Full Account ◽  
Heart Beating ◽  
External Conditions ◽  
Work Done ◽  
Made In

In the year 1881 I briefly described (1) a method of experimenting by which the heart and lungs of a Dog or Cat could be completely isolated physiologically from the remainder of the body of the animal, and kept alive some hours for study in an apparently normal condition, the heart beating regularly and maintaining a good arterial pressure. Since then I have been at work investigating the influence of various conditions upon the pulse-rate of Dogs’ hearts so isolated; while under my supervision several of my pupils have been engaged in studying the work done in a unit of time by such hearts under different external conditions. As regards the effects of variations of arterial pressure upon the pulse-rate of the isolated Dog’s heart, my results have already been published (2); and detailed observations as to the influence of variations in venous pressure will shortly be printed. But in so far as the influence of temperature variations upon the cardiac rhythm is concerned, only a brief preliminary announcement (3) has been made. In the present paper I propose to give a full account of my experiments upon this subject, which is one that, apart from and in addition to its purely physiological interest, has considerable practical importance in connexion with inquiries as to the immediate cause of the quick pulse so constantly found in warm-blooded animals suffering from fever.

The effect of armored skin on the swimming of longnose gar, Lepisosteus osseus

1992 ◽  
Vol 70 (6) ◽  
pp. 1173-1179 ◽  
Author(s):  
Paul W. Webb ◽  
Doug H. Hardy ◽  
Vicki L. Mehl
Keyword(s):  
Muscle Mass ◽  
Swimming Speed ◽  
The Body ◽  
Critical Swimming Speed ◽  
Elapsed Time ◽  
Fast Start ◽  
Longnose Gar ◽  
The Difference ◽  
Early Radiation ◽  
Work Done

Fast-starts and steady swimming were compared for two piscivorous fishes, the longnose gar (Lepisosteus osseus), which has an integument armored with ganoid scales, and the unarmored tiger musky (Esox sp.). The body was similarly flexed by both species during fast-starts and steady swimming. Therefore, the heavy integument of the gar did not affect flexibility during swimming. Distance traveled in a given elapsed time during fast-starts was lower for the gar, which averaged 65% of the work done by the musky. On the basis of differences in muscle mass, gars would be expected to perform 72% of the work of muskies during a fast-start. The heavier integument of the gar was estimated to contribute about 90% to the reduced fast-start performance. In steady swimming, mechanical power requirements at a given speed were similar for both gar and musky. Therefore, steady swimming costs do not appear to be affected by armor. The critical swimming speed of gars was 1.9 body lengths/s compared with 3.4 body lengths/s for muskies, but the difference could not be attributed to differences in armoring. The slip speed at which gars first began to swim was 1.21 body lengths/s compared with 0.75 body lengths/s for muskies. Higher station-holding performance is probably not important to modern gars and esocids, but may have been advantageous during the early radiation of fishes.

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