How to use Contraction in a sentence
The active contraction of muscular tissue has no counterpart in the plant.
A slight degree of contraction of muscle seems the substratum of all attention.
It is a brief extension of the limb at the knee-joint, due to a simple contraction of the extensor muscle, elicited by a tap or other short mechanical stimulus applied to the muscle fibres through the tendon of the muscle.
Apparently there is an influence on the afferent nerves of the part which causes a reflex contraction - some authors say dilatation - of the vessels in the internal organs that are under the control of the same segment of the nervous system as that supplying the area of skin from which the exciting impulse comes.
In the Gymnolaemata protrusion is effected by the contraction of the parietal muscles, which pass freely across the body-cavity from one part of the body-wall to another.Advertisement
Coincidently with the persistence of the tonic contraction, the higher and volitional centres seem to lie under a spell of inhibition; their action, which would complete or cut short the posture-spasm, rests in abeyance.
But whilst the characteristic action of atropine is to dilate the blood-vessels, its first action is to stimulate the vaso-motor centre - thereby causing temporary contraction of the vessels - and to increase the rapidity of the heart's action, so that the blood-pressure rapidly rises.
The later explanation that Summanus is a contraction from Summus Manium (the greatest of the Manes), and that he is to be identified with Dis Pater, is now generally rejected.
The great fluidity of bronze when melted, the slightness of its contraction on solidifying, together with its density and hardness, make it especially suitable for casting, and allow of its taking the impress of the mould with extreme sharpness and delicacy.
But this cannot continue indefinitely; when the density is too great the matter ceases to behave as a true gas, and the contraction is insufficient to maintain the heat.Advertisement
It has been found that in many cases of this disease the pressure of blood within the arteries becomes increased, probably from spasmodic contraction of the arteries themselves.
The muscular system of the Scyphomedusae is developed on the subumbral surface as a system of circularly disposed fibres which by their contraction make the umbrella more concave and diminish its FIG.
The reason probably is that the application of cold causes contraction of the arteries leading to the inflamed part, while heat by dilating the vessels around forms a side channel through which the blood passes, the tension in the seat of inflammation being thus lessened in both cases.
Blisters applied at some distance from inflamed parts are also sometimes useful; and probably they produce this good effect by causing a reflex contraction of the arteries in the inflamed part, and thus acting like a cold application.
Irritation of sensory nerves tends to cause contraction of the vessels, and to raise the blood pressure, and where pain is ffi, present opium or morphine is the most efficient sedative.Advertisement
The tangential pressures which are known to be set up in the earth's crust - either by the contraction of the interior or in some other way - caused the deposits of this sea to be crushed up against the rigid granites and other old rocks of the peninsula and finally led to the whole mass being pushed forward over the edge of the part which did not crumple.
The present constitution (as revised in 1908) forbids the contraction of a state debt exceeding $250,000 except for repelling an invasion or suppressing an insurrection, and the borrowing power of the minor civil divisions is restricted by a general law.
By their contraction the muscles of the taeniolae drag the hypostome down and so produce the appearances which have been interpreted as a stomodaeal invagination.
In consequence of the radiation of heat the whole body will be more condensed than before, but whether it is hotter or colder than before will depend on whether the contraction set up is more or less than enough to restore an exact balance.
It is equally clear that there is a point beyond which contraction cannot go, and thereafter, if not before, the body will begin to grow colder.Advertisement
The movement towards contraction and consequent rise of temperature which radiation sets up, like other motions, overruns the equilibriumpoint, only however by a minute amount; the accumulated excesses from all past time now stored in the sun would maintain its radiations at their present rate for nX3000 years, that is, for a few thousand years only.
Such a rate of change would be quite insensible, and we can affirm that for recent times there is no reason to look for any other factor than contraction; but if we consider the remote past it is a different matter.
The fall of meteoric matter into the sun must be a certain source of energy; if considerable, this external supply would retard the sun's contraction and so increase its estimated age, but to bring about a reconciliation with geological theory, very nearly the whole amount must be thus supplied.
A second objection is that it fails in its purpose, because 20,000,000 years ago it would give a sun quite as much changed as the contraction theory gave.
By means of circularly disposed muscular fibrils formed from the endoderm the tentacles can be protracted or thrust out after contraction.Advertisement
Much the same tendency exists with respect to all drops between B and E, but at F the wind has begun to accommodate itself to the new regime and to assume more regular forward motion, and as J is approached, where vertical contraction of the passage through which the wind must pass takes place, there is an increasing tendency to lift the raindrops beyond their proper limits.
It is essential that this contraction shall not proceed to such an extent as may possibly produce cracking.
Drying is retarded, and the contraction due to a given degree of drying is greatly reduced, by the presence of sand and small stones among the clay.
As erosion proceeds, the contraction of the space from which the clay is washed continues, chiefly by the sinking down of the clay above the sand.
But like every pure theory the principles of conjugate pressures in earth may lead to danger if not applied with due consideration for the angle of repose of the material, the modifications brought about by the limited width of artificial embankments, the possible contraction away from the masonry, of clayey materials during dry weather for some feet in depth and the tendency of surface waters to produce scour between the wall and the embankment.
The faces of the work may be of squared masonry, thoroughly tied into the hearting; but, in view of the expansion and contraction mentioned below, it is better that the face masonry should not be coursed.
Serious movement from expansion and contraction does not usually extend to levels which are kept moderately damp, or to the greater mass of the dam, many feet below high-water level.
By reason of the constantly changing temperatures and the frequent filling and emptying of the reservoir, expansion and contraction, which are always at work tending to produce relative movements wherever one portion of a structure is weaker than another, must have assisted the water-pressure in the extension of the horizontal cracks, which, growing slowly during the fifteen years, provided at last the area required to enable the intrusive water to overbalance the little remaining stability of the dam.
Pulleys are usually cast in one piece, and the proportions of the various parts are designed to resist the unknown stresses due to contraction of the casting in cooling, in addition to the stresses to which pulleys are subjected in use.
The number of the arms is arbitrary, and they may be curved to diminish the liability to fracture from contraction in the cooling of the cast iron, but in other respects are preferably straight, since they are then lighter and stronger.
The drug greatly raises the blood-pressure by causing extreme contraction of the arteries.
Of great practical importance is the fact that the cornutine causes rhythmic contractions such as naturally occur, whilst the sphacelinic acid produces a tonic contraction of the uterus, which is unnatural and highly inimical to the life of the foetus.
In external nature there are expansion and contraction History which correspond to spontaneity and reflection.
Epsom (a contraction of Ebbisham, still the name of the manor) first came into notice when mineral springs were discovered there about 1618.
The circulation is maintained by the rhythmical contraction of the afferent vessel and by less regular contractions of some of the other vessels.
After pollination the female flower becomes drawn below the surface by the spiral contraction of the long stalk, and the fruit ripens near the bottom.
The lower Nile valley, however, forms an exception; flint implements of a palaeolithic type have been found near Thebes, not only on the surface of the ground, which for several thousand years has been desert owing to the contraction of the river-bed, but also in stratified gravel of an older date.
Then with an uniaxal plate perpendicular to the optic axis, the black cross is replaced by two lines, on crossing which the rings are discontinuous, expansion or contraction occurring in the quadrants that contain the axis of the quarter-wave plate, according as the crystal is positive or negative.
In it we must distinguish (1) Portuguese (Portuguez, perhaps a contraction from the old Porlugalez = Portugalensis), the language of the kingdom of Portugal and its colonies in Africa, Asia and America (Brazil); (2) Galician (Gallego), or the language of the old kingdom of Galicia (the modern provinces of Pontevedra, La Coruna, Orense, and Lugo) and of a portion of the old kingdom of Leon (the territory of Vierzo in the province of Leon).
The withers may be moderately high and thin; the chest well developed, but not too wide or deep; the shoulder should lie well on the chest, and be oblique and well covered with muscle, so as to reduce concussion in galloping; the upper and lower arms should be long and muscular; the knees broad and strong; legs short, flat and broad; fetlock joints large; pasterns strong and of moderate length; the feet should be moderately large, with the heels open and frogs sound - with no signs of contraction.
When irritated they eject with considerable force the contents of their slime reservoirs by means of the sudden contraction of the muscular body-wall.
In many varieties of the Greek alphabet this symbol was used, as it always was in Latin, for the long as well as the short o-sound and also for the long vowel (in the Ionic alphabet written ov) which arose from contraction of two vowels or the loss of a consonant (57jXoUTE=677XOere, o'lxovs = oircovs).
In addition to diffuse pigment (mostly in the epidermis), the skin contains granular pigment stored up r' in cells, the chromatophores, restricted to the cutis, which are highly mobile and send out r2 branches which, by contraction and expansion, may rapidly alter the coloration, most batrachians being in this respect quite comparable to the famous chameleons.
As the doe strained, one tiny hoof emerged, and then disappeared as the contraction subsided.
The doe lurched to her feet and immediately went into another contraction.
She tugged the gloves on and waited until the contraction passed.
With eccentric contraction, the muscle fibers lengthen to lower the weight.
Many types of smooth muscle also contain gap junctions and muscarinic acetylcholine receptors, but here acetylcholine normally leads to contraction.
The two BTO breeding bird Atlases indicated that a 29% contraction in range occurred in Britain between the late 1960s and early 1990s.
Rigor Explaining the development of rigor is a serious undertaking, because first you must understand the biochemistry of muscle contraction.
I too managed to use the yoga breathing for the first 12 hours of contraction.
During activation of contraction in skeletal muscle, sarcoplasmic reticulum calcium -release channels open.
Last, but not least, we've added magnesium chelate for optimum muscle contraction.
Oxytocin A hormone, produced by the pituitary gland, which stimulates contraction of the uterus.
In the case of a muscle cell, depolarisation triggers muscle contraction.
Between 1983 and 2001 the UK, France and Belgium underwent a contraction in their manufacturing bases.
As fatigue sets in, the muscle tissue is no longer capable of meeting the metabolic requirements needed to sustain the contraction.
Minor shocks may also cause injury following involuntary muscle contraction.
In an eccentric contraction, the muscle fibers lengthen to lower the weight.
With this form of contraction, the muscle is allowed to shorten during an isotonic contraction.
Clean intermittent catheterisation will temporarily relieve the symptoms and signs of obstruction or decreased detrusor contraction (Moore, 1995 ).
Lessons cover topics ranging from muscle contraction to cardiac activity to reaction time.
As one economy after another sinks into contraction, output subsides nearly everywhere -- more layoffs and closed factories, more unsold goods.
Ideally, both contraction and integration with host myocardium should have occurred in order for the therapy to be effective.
The only downside was that I was feeling slightly nauseous in the middle of each contraction.
Sensory nerve cells carry information about muscle tension and body position to motor nerve cells in the spinal cord to control muscle contraction.
These molecules induce smooth muscle contraction and enhance vascular permeability.
An ideal prokinetic drug should either enhance the contraction of a damaged muscle or normalize the coordination of a damaged myenteric plexus.
As your muscles get stronger, the contraction can be held for longer and more pull-ups achieved.
More show came away with each contraction and at about 7.30am I started to feel a bit pushy with each contraction.
They are in a state of extreme contraction, far exceeding the usual rigor mortis.
If the stress gets too severe, the body suffers overload and locks the stress into itself in lines of tension and contraction.
Muscle Types Muscle tissue consists of fibers (cells) that are highly specialized for the active generation of force for contraction.
The phase transition is accompanied by a 9.8% volume contraction.
Calcium entry during the plateau is essential for contraction; blockers of L-type Ca 2+ channels (e.g. verapamil) reduce force of contraction.
This shivering would then turn into a really vicious contraction.
This enormous capacity for expansion and contraction is astonishing if we believe matter to be continuous, but if we imagine air to be made up of little particles separated by relatively large empty spaces the changes in volume are more easily conceivable.
We know nothing quantitatively of the radiations from a nebulous body; and it is quite possible that the loss of radiant energy in this early stage was very small; but it is at least as certain as any other physical inference that 17,000,000 years ago the earth itself was of its present dimensions, a comparatively old body with sea and living creatures upon it, and it is impossible to believe that the sun's radiations were wholly different; but, if they were not, they have been maintained from some other source than contraction.
If, therefore, with such materials the work is well done, and is not subsequently liableto be wasted or disintegrated by expansion or contraction or other actions which in the process of time affect all exposed surfaces, it is clear that 15 to 20 tons per sq.
In portions of the structure liable to important changes of pressure from the rise, and fall of the water and subject to the additional stresses which expansion and contraction by changes of temperature and of moisture induce, and in view of the great difficulty of securing that the average modulus of elasticity in all parts of the structure shall be approximately the same, it is probably desirable to limit the calculated load upon any external work, even of the best kind, to 15 or 20 tons per sq.
Schrader, de St Sand and Wallon, that, taken as a whole, the range must be regarded, not as formed on the analogy of a fern-frond or fish-bone, with the lateral ridges running down to the two opposite plains, but rather as a swelling of the earth's crust, the culminating portion of which is composed of a series of primitive chains, which do not coincide with the watershed, but cross it obliquely, as if the ground had experienced a sidewise thrust at the time when the earth's crust was ridged up into the long chain under the influence of contraction.
The head is violently displaced followed by reflex contraction in the opposite direction.
Regarding the vagal reflexes, the most significant results arose from the heart rate changes immediately after isometric muscle contraction.
There is the rare occasion when a kitten may become stuck and need a gentle tug from you in order to free it when mom has the next contraction.
When you measure for cutting be sure to leave one quarter inch space on the top and bottom to allow for expansion and contraction.
Doctors may recommend a prescription muscle relaxant if a severe muscle contraction accompanies the headache.
Always allow for the expansion and contraction of the siding by allowing a space between the nail head and the panel.
The two most important things to remember are to allow enough room for expansion and contraction of the panels and to keep checking to make sure everything stays level as you move from panel to panel.
A muscle cramp is an involuntary contraction that cannot be controlled.
The duration of the contraction varies, lasting anywhere from a few seconds to 10 minutes.
You should avoid clenching the muscle because that can cause pain that may stimulate an even tighter contraction.
Diastolic murmurs occur during relaxation of the heart between beats, and systolic murmurs occur during contraction of the heart muscle.
Continuous murmurs occur during both the relaxation and contraction of the heart.
During a contraction, the infant experiences pressure that pushes it against the cervix to assist with the dilatation.
Generally, there is a rise in the uterus due to a contraction and a gush of blood as the placenta is expelled.
When both forceps are in place, the doctor pulls on them to help the baby through the birth canal during a uterine contraction.
A very strong contraction cannot be indented and will feel as hard as the forehead.
A moderate contraction will palpate like the feel of the chin and an easy contraction feels like the end of the nose.
The correct balance of electrolytes is crucial to many body functions, including muscle contraction and nerve impulse transmission.
Convulsions-Also termed seizures; a sudden violent contraction of a group of muscles.
Electrolytes control the fluid balance of the body and are important in muscle contraction, energy generation, and almost all major biochemical reactions in the body.
Datrolene sodium (Dantrium) acts on the muscles to directly interfere with the chemistry of the muscle contraction.
Muscle spasm-Localized muscle contraction that occurs when the brain signals the muscle to contract.
There is no voluntary muscular contraction by the individual who is being passively moved.
Repeated infections eventually lead to contraction and turning-in of the eyelids.
Low-toned muscles contract very slowly in response to a stimulus and cannot maintain a contraction for as long as a normal muscle.
A child with low muscle tone has muscles that are slow to start a muscle contraction.
Muscles contract very slowly in response to a stimulus and cannot maintain a contraction for as long as a normal muscle.
Because low-toned muscles do not fully contract before they again relax, they remain loose and very stretchy, never achieving their full potential of sustaining a muscle contraction over time.
The most common problem is internal rotation contracture (permanent muscle contraction) of the shoulder.
Other medications include Digoxin, which strengthens the contraction of the heart, slows the heartbeat, and removes fluid from tissues, and antihypertensive medications that treat high blood pressure.
Tension headaches-muscular contraction headaches that occur periodically or daily (chronic daily headache).
Traditional theories about headaches link tension-type headaches to muscle contraction, and migraine and cluster headaches to blood vessel dilation (swelling).
If the practitioner feels that a baby may be at risk for problems during pregnancy, non-stress tests, biophysical profiles, or even contraction stress tests are performed twice a week to monitor fetal well-being.
In a concentric contraction, the muscle will rise to meet the resistance of the specific exercise.
Carmen stood and backed away as the doe lurched to her feet and went into another contraction.
The truth appears to be that a hardened steel rod generally behaves like one of iron or soft steel in first undergoing extension under increasing magnetizing force, and recovering its original length when the force has reached a certain critical value, beyond which there is contraction.
With few exceptions tapeworms select the small intestine for their station, and in this situation execute active movements of extension and contraction.
Thus in the Phylactolaemata the contraction of the muscular body-wall exerts a pressure on the fluid of the body-cavity and is the cause of the protrusion of the polypide.
In the branching Ctenostomes the entire body-wall is flexible, so that the contraction of a parietal muscle acts equally on the two points with which it is connected.
It is joined to the rigid body-wall by numerous muscle-fibres, the contraction of which must exert a pressure on the fluid of the body-cavity, thereby protruding the polypide.
Natural arrest of haemorrhage arises from (I) the coagulation of the blood itself, (2) the diminution of the heart's action as in fainting, (3) changes taking place in the cut vessel causing its retraction and contraction.
The name is pronounced Boosheer, and not Bew-shire, or Bus-hire; modern Persians write it Bushehr and, yet more incorrectly, Abushehr, and translate it as "father of the city," but it is most probably a contraction of Bokht-ardashir, the name given to the place by the first Sassanian monarch in the 3rd century.
It mixes with water in all proportions, the mixing being attended by a contraction in volume and a rise in temperature; the maximum contraction corresponds to a mixture of 3 molecules of alcohol and I of water.
It could be explained as a contraction of Malachiah, messenger of Yahweh "; but the Septuagint is probably right in not regarding it as a proper name (" by the hand of His messenger ").
The alloys of tin and gold are hard and brittle, and the combination of the metals is attended with contraction; thus the alloy SnAu has a density 14.243, instead of 14.828 indicated by calculation.
The crop is followed by a proventriculus which, in the higher Hymenoptera, forms the so-called " honey stomach," by the contraction of whose walls the solid and liquid food can be separated, passed on into the digestive stomach, or held in the crop ready for regurgitation into the mouth.
A correction has, of course, to be made for the expansion or contraction of the mercury thread if the temperature of reading differs much from that of reversing.
The longitudinal extension is dy/dx, and therefore the radial contraction is n/r= udy/dx.
Expansion and contraction broke the high arch and the connexions between the arches.
At the same time a piece was cut off the park to prevent the undue contraction of the Place by the necessary bringing forward of the palace, and the pits which played a certain part in the revolution of 1830 when the Dutch defended the park for a few days against the Belgians were filled up. The Palais de la Nation was constructed between 1779 and 1783, also during the Austrian period.
The Babylonian deity Nabu (in Old Testament Nebo) is a contraction from Na-bi-u, which thus corresponds closely with the Hebrew nablti a and originally signified the speaker or proclaimer of destiny.
Then by contraction of the tentacles the prey is drawn into the mouth.
By the contraction of the subumbral circular muscles the concavity of the subumbrella is increased, and as water is thereby forced out of the subumbral cavity the animal is jerked upwards.
Bodywall usually traversed by a network of canals serving by their contraction to expand the disk.
It dissolves in water in all proportions with at first a contraction and afterwards an increase in volume.
The first blow towards its gradual contraction was struck when Napoleon ordered 22,000 oaks to be cut down in it to build the celebrated Boulogne flotilla for the invasion of England.
Later the new fibrous tissue undergoes contraction and the liver becomes smaller than natural.
The distress is due to spasmodic muscular contraction, and it comes on at intervals, each attack increasing the patient's misery.
The adductor muscles placed in the concavity of the shells act upon the long arms of the lever at a mechanical advantage; their contraction keeps the shells shut, and stretches the ligament or spring h.
At the side of each of the four scales on the stem of the hydrometer is en r ' graved a set of small numbers indicating the contraction in volume which would be experienced if the requisite amount of water (or spirit) were added to bring the sample tested to the proof strength The hydrometer constructed by Dicas of Liverpool is provided with a sliding scale which FIG.
It is also necessary, he inferred, for all muscular movements, and he thought there was reason to believe that the sudden contraction of muscle is produced by its combination with other combustible (salino-sulphureous) particles in the body; hence the heart, being a muscle, ceases to beat when respiration is stopped.
The final arrest is due to paralysis of the respiratory centre in the medulla oblongata, hastened by a quasi-asthmatic contraction of the non-striped muscular tissue in the bronchial tubes, and by a "water-logging" of the lungs due to an increase in the amount of bronchial secretion.
Whether administered in the form of the official lamella or by subcutaneous injection, physostigmine causes a contraction of the pupil more marked than in the case of any other known drug.
This action, at first sight somewhat obscure, is due to the extreme pupillary contraction which removes the mass of the iris from pressing upon the spaces of Fontana, through which the intraocular fluids normally make a very slow escape from the eye into its efferent lymphatics.
The card nearly floats in a bowl filled with distilled water, to which 35% of alcohol is added to prevent freezing; the bowl is hermetically sealed with pure india-rubber, and a corrugated expansion chamber is attached to the bottom to allow for the expansion and contraction of the liquid.
Some thought they slid like solids; others that they flowed like liquids; others that they crawled by alternate expansion and contraction, or by alternate freezing and melting; others, again, that they broke and mended.
When the yellow line of nitrogen has disappeared, and no further contraction seems to be in progress, the oxygen maybe removed by cautious introduction of hydrogen.
Berthelot that under the influence of the silent electric discharge, a mixture of benzene vapour and argon underwent contraction, with formation of a gummy product from which the argon could be recovered.
Not only is the respiratory centre stimulated but the cardiac centre is acted upon both directly by the drug and indirectly for a time by the enormous rise in blood pressure due to the contraction of the arterioles all over the body.
On mixing nitric acid with water there is a rise of temperature and a contraction in volume.
When the larvae are disturbed the similarity is produced with startling suddenness by the telescopic contraction of the anterior segments in such a manner as to suggest a triangular, pointed head with two large dorsal eyes.
Within the crust of the earth, whether by the contraction of the interior or in any other way, tangential pressures were set up. Since the crust is not of uniform strength throughout, only the weaker portions yielded to the pressure; and these were crumpled up against the more resisting portions and sometimes were pushed over them.
But this excess of their contraction is resisted by the almost incompressible inner layers so that the outer layers are prevented from contracting as much as they naturally would if unopposed, and they are thereby virtually stretched.
Later on the cooling of the inner layers becomes more rapid than that of the outer ones, and on this account their contraction tends to become .greater than that of the outer ones.
Because the outer and inner layers are integrally united, this excess of contraction of the inner layers makes them draw outward towards and against the outer layers, and because of their thus drawing outward the molten lake within no longer suffices to fill completely the central space, so that its upper surface begins to sink.
Because this pipe is due to the difference in the rates of contraction of interior and exterior, it may be lessened by retarding the cooling of the mass as a whole, and it may be prevented from stretching down deep by retarding the solidification of the upper part of the ingot, as, for instance, by preheating the top of the mould, or by covering the ingot with a mass of burning fuel or of molten slag.
Because the volume of the pipe represents the excess of the contraction of the inner walls and the molten lake jointly over that of the outer walls, between the time when the lake begins to ebb and the time when even the axial metal is too firm to be drawn further open by this contraction, the space occupied by blowholes must, by compensating for part of this excess, lessen the size of the pipe, so that the more FIG.
Aeolotachic contraction further leads to the " pipes " or contraction cavities already described in § 121, and the procedure must be carefully planned first so as to reduce these to a minimum, and second so as to induce them to form either in those parts of the casting which are going to be cut off and re-melted, or where they will do little harm.
Its first action on any of the body-tissues is upon unstriped muscle, so that the first consequence of its absorption is a contraction of the arteries and arterioles.
Added to the greater force of cardiac contraction is a permanent tonic contraction of the organ, so that its internal capacity is reduced.
The contraction corresponding to the melting of i gramme of ice was assumed to be.
Polygordius and Protodrilus live in sand, but while the former moves by means of the contraction of its body-wall muscles, Protodrilus can progress by the action of the bands of cilia surrounding its segments, and of the longitudinal ciliated ventral groove.
Loans were needed for military and other purposes, and paragraph 14 itself declares that it cannot be employed for the contraction of any lasting burden upon the exchequer, nor for any sale of state patrimony.
The contraction of this heart, which is not rhythmic, brings about the expansion of the tentacles and lophophore.
Beads were made by winding thin threads of glass on copper wires, and the greater contraction of the copper freed the bead when cold.
This shortening is called contraction.
By tonic contraction is meant a prolonged and equable state of tension which yields under analysis no element of intermittent character.
The muscular wall of the blood-vessels also exhibits tonic contraction, which, however, seems to be mainly traceable to a continual excitation of the muscle cells by nervous influence conveyed to them along their nerves, and originating in the great vaso motor centre in the bulb.
Another mode of manifestation of contractility by muscles is the rhythmic. A tendency to rhythmic contraction seems discoverable in almost all muscles.
Rhythmic contraction is also characteristic of certain groups of skeletal muscles, e.g.
A form of contraction intermediate in character between the tonic and the rhythmic is met in the auricle of the heart of the toad.
In the heart muscle during a brief period after each beat, that is, after each single contraction of the rhythmic series, the muscle becomes inexcitable.
But in the skeletal, voluntary or striped muscles a second stimulus succeeding a previous so quickly as to fall even during the continuance of the contraction excited by a first, elicits a second contraction.
This second contraction starts from whatever phase of previous contraction the muscle may have reached at the time.
A third stimulus excites a third additional contraction, a fourth a fourth, and so on.
The increments of contraction become, however, less and less, until the succeeding stimuli serve merely to maintain, not to augment, the existing degree of contraction.
But in the ordinary skeletal muscles the amount of the muscular contraction is for a short range of quantities of stimulus (of above threshold value) proportioned to the intensity of the stimulus and increases with it.
A value of stimulus, however, is soon reached which evokes a maximal contraction.
Further increase of contraction does not follow further increase of the intensity of the stimulus above that point.
Just as in a nerve fibre, when excited by a localized stimulus, the excited state spreads from the excited point to the adjacent unexcited ones, so in muscle the "contraction," when excited at a point, spreads to the adjacent uncontracted parts.
The tenth contraction usually exhibits the culmination of this so-called "staircase effect."
The effect of the fatigue substances upon the contraction of the tissue is manifest especially in the relaxation process.
The inference is that the "fatigue substances" generated in the muscle fibres in the course of their prolonged contraction injure and paralyse the motor end plates, which are places of synapsis between nerve cell and muscle cell, even earlier than they harm the contractility of the muscle fibres themselves.
These muscles exhibit a certain constant condition of slight contraction, which disappears on severance of the nerve that innervates the muscle.
It is a muscular tonus of central source consequent on the continual glow of excitement in the spinal motor neuron, whose outgoing end plays upon the muscle cells, whose ingoing Yet when the muscular contraction is taken as index ology.
The brevity of the interval between the tap on the knee and the beginning of the resultant contraction of the muscle seems such as to exclude the possibility of reflex development.
In the dog it has been proved that after removal from the animal of every vestige of its cortex cerebri, it still executes habitual acts of great motor complexity requiring extraordinarily delicate adjustment of muscular contraction.
At the best, however, it is not generally suited for the finest work, as the great contraction of iron in passing from the fluid to the solid state renders the cast somewhat blunt and spiritless.
The presence of the iron core has been made visible by the splitting of the figure, owing to the unequal contraction of the two metals.
Other pulses, lentils, &c., are extensively grown, but the area under these crops is liable to great contraction in years of drought, as it consists for the most part of unirrigated lands.
This can be determined by a direct calibration, by inserting a known quantity of water at a known temperature and observing the contraction, or weighing the mercury drawn into the apparatus.
It was shown by Homer Lane that a mass of gas held in equilibrium by the mutual gravitation of its parts actually grows hotter through radiating heat; the heat gained by the resulting contraction more than counterbalances that lost by radiation.
Eriu was itself almost certainly a contraction from a still more primitive form Iberiu or Iveriu; for when the name of the island was written in ancient Greek it appeared as Iovcpvia (Ivernia), and in Latin as Iberio, Hiberio or Hibernia, the first syllable of the word Eriu being thus represented in the classical languages by two distinct vowel sounds separated by b or v.
These myotomes enable it to swim rapidly with characteristic serpentine undulations of the body, the movements being effected by the alternate contraction and relaxation of the longitudinal muscles on both sides.
As meaning some form of feudal service rendered by tenants to their superiors, it survived for a long time in the Scottish phrase "arriage and carriage," this form of the word being due to a contraction into "arage."
Galvani had made in 1790 his historic observations on the muscular contraction produced in the bodies of recently killed frogs when an electrical machine was being worked in the same room, and described them in 1791 (De viribus electricitatis in motu musculari commentarius, Bologna, 1791).
He studied the nature of muscular contraction, causing a muscle to record its movements on a smoked glass plate, and he worked out the problem of the velocity of the nervous impulse both in the motor nerves of the frog and in the sensory nerves of man.
Some anomalies, both of metre and of sense, may be removed by judicious emendation; and many lines become smooth enough, if we assume a crasis of open vowels of the same class, or a diphthongal pronunciation of others, or contraction or silence of certain suffixes as in Syriac. The oldest elegiac utterances are not couched in this metre; e.g.
But if such a remedy were given alone it might, and probably would, act on the arteries as well as the heart, and by causing the contraction of the vessels do more harm than good.
During the early period of their sojourn in the pouch, the blind, naked, helpless young creatures (which in the great kangaroo scarcely exceed an inch in length) are attached by their mouths to the nipple of the mother, and are fed by milk injected into their stomach by the contraction of the muscle covering the mammary gland.
Verworn to depend upon stimulation to contraction or the reverse.
There is a superior limit to the quantity of energy which can be derived from contraction.
The constitution forbids the contraction of a state debt exceeding $1,000,000.
West Virginia's share of the Virginia debt which existed when West Virginia was set off from Virginia has not yet been determined (see below, § History), but other than this the state has no debt, and the contraction of a state debt other than " to meet casual deficits in the revenue, to redeem a previous liability of the state, to suppress insurrection, repel invasion or defend the state in time of war " is forbidden by the constitution.
Ordinarily the alternate expansion and contraction of the atmosphere which takes place under such circumstances would draw in a supply of moisture from the ocean, but the heated interior, covering some 900,000 sq.
But partly from lack of firm financial administration, partly through the increase of military and naval expenditure (which in 1887 amounted to 9,000,000 for the army, while special efforts were made to strengthen the navy), and principally through the constant drain of railway construction and public works, the demands upon the exchequer grew largely to exceed the normal increase of revenue, and necessitated the contraction of new debts.
If then by the contraction of the earth's interior the outer crust were forced to accommodate itself to a smaller nucleus, the central softer belt would yield by crumpling; the more rigid masses to the north and south, if they gave way at all, would yield by faulting.
The inversion of the proboscis is effected directly by the contraction of these a, Siphon.
Others he treated very superficially, and in none of his experiments apparently did he attend to the diminution of efflux arising from the contraction of the liquid vein, when the orifice is merely a perforation in a thin plate; but he appears to have been the first who attempted to ascribe the discrepancy between theory and experiment to the retardation of the water's velocity through friction.
Their function is to retract the introvert, which is protruded again by the contraction of the circular muscles of the skin; these, compressing the fluid of the body-cavity, force forward the anterior edge of the introvert.
The eyes are closed, the maintenance of posture by active contraction is replaced by the recumbent pose which can be maintained by static action and the mere mechanical consistence of the body, the ears are screened from noise in the quiet chamber, the skin from localized pressure by a soft, yielding couch.
Therefore, headaches may result from contraction of the muscles of the scalp, face or neck; dilation of the blood vessels in the head; or brain swelling that stretches the brain's coverings.
Failure to progress, however, can only be diagnosed with documentation of adequate contraction strength.
The rapid, uncontrolled muscle contraction, or spasm, happens unexpectedly, with either no stimulation or some trivially small one.
The terms cramp and spasm can be somewhat vague, and they are sometimes used to include types of abnormal muscle activity other than sudden painful contraction.
Fasciculation is a type of painless muscle spasm, marked by rapid, uncoordinated contraction of many small muscle fibers.
Normal voluntary muscle contraction begins when electrical signals are sent from the brain through the spinal cord along nerve cells called motor neurons.
Abnormal contraction may be caused by unusual activity at any stage in this process.
Certain mechanisms within the brain and the rest of the central nervous system help regulate contraction.
The muscle membrane itself may be overly sensitive, causing contraction without stimulation.
Calcium ions may not be recaptured quickly enough, causing prolonged contraction.
These conditions cause stiffness due to delayed relaxation of the muscle but do not cause the spontaneous contraction usually associated with cramps.
Fasciculation may occur at rest or after muscle contraction and may last several minutes.
Platelets, tiny colorless cells in the blood, initiate contraction of damaged blood vessels so that less blood is lost.
During contractions, the normal pattern is for the FHR to slow somewhat, picking up again as the contraction ends.
Certain variations in this pattern, such as precipitous drops in the FHR at the end of a contraction can constitute a true life or death situation requiring emergency delivery of the baby.
Maternal uterine activity is noted and recorded when the pressure of a contraction pushes on a sensor, which is on the underside of a tocodynanometer.
An internal monitor may also be used to determine the actual strength of the contraction as well as the resting tone of the uterus.
A good labor pattern that facilitates cervical dilation can be calculated by taking the difference in pressure between the peak of the contraction and the resting tone and adding them up over a ten-minute period.
During a contraction, the flow of oxygen (from the mother) through the placenta (to the baby) is temporarily blocked.
The first sign that a baby is not getting enough oxygen between contractions is often a drop in the baby's heart rate after a contraction, called a late deceleration.
The baby's heart rate recovers to a normal level between contractions, only to drop again after the next contraction.
Myotonic dystrophy is a progressive disease in which the muscles are weak and slow to relax after contraction.
As of 2004 the theory was that by linking these two networks, the complex acts as a "shock absorber," redistributing and evening out the forces generated by contraction of the muscle, thereby preventing rupture of the muscle membrane.
It is characterized by delay in the ability to relax muscles after forceful contraction (myotonia) and wasting of muscles, as well as other abnormalities.
Exercise-induced bronchospasm-A sudden contraction in the lower airway that causes breathing problems and is brought about by heavy exercise.
Phosphorus-helps form bones and teeth, supports cell growth, and regulates heart muscle contraction and kidney function.
To compensate for this, the person may be asked to perform some muscle contraction, such as clenching teeth or grasping and pulling the two hands apart.
The contraction stress test (CST) is similar to the NST except the FHR is evaluated for accelerations, 15 beats higher than baseline lasting 15 seconds, and in response to contractions as well.
During a contraction, the blood flow to the baby is temporarily restricted, which provides a form of "stress" to the baby.
When oxytocin is administered IV, it is called an oxytocin contraction stress test (OCT).
It is coated with mucus and surrounded by muscles, and pushes food to the stomach by sequential waves of contraction.
Electrical stimulation of the muscles causes contraction, and the force of contraction pulling on the skeleton causes movement of the arm, hand, and fingers.
Contraction of the biceps muscle, located on the top of the upper arm, pulls on the forearm to flex the elbow and bend the arm.
Contraction of the triceps, located on the opposite side, extends the elbow and straightens the arm.
Within the spine, these muscles are normally wired so that willed (voluntary) contraction of one is automatically accompanied by blocking of the other.
In other words, the command to contract the biceps provokes another command within the spine to prevent contraction of the triceps.
Spinal cord or brain injury can damage this control system and cause involuntary simultaneous contraction and spasticity, an increase in resistance to movement during motion.
Some diseases that cause sustained muscle contraction limited to a particular muscle group (focal dystonia) are inherited, but others are caused by trauma.
Dantrolene sodium (Dantrium) acts on the muscles to directly interfere with the chemistry of the muscle contraction.
For example, in the first video, the Slide Pop, after showing the basic moves at speed, he points out how the final contraction includes a bit of a crouch.
It's also important to offer to give a two-week notice even though you are an independent contraction.
The external contraction monitor does not monitor the strength of your contractions, only how far apart they are and how long they last.
Cleansing breaths can be used at the beginning and end of each contraction.
If you start having contractions, take a few minutes as a break after each contraction before stimulating the spot again.
Once you have found it, press deeply and rub in a circular manner until a contraction comes on, then stop.
At the end of the contraction, begin stimulating again.
When there is a deficiency of this mineral, cramping in the muscles and problems related to muscle contraction can occur.
Calcium is absolutely essential for muscle contraction.
Calcium is an essential mineral for bone health, proper function of the nervous systems and muscle contraction.
Calcium also plays a key role in contraction and expansion of blood vessels, muscle contraction, and nerve transmission.
Christa Lehnert-Schroth, physical therapist and author of The Schroth Method, which outlines her own scoliosis treatment program, warns against poses that encourage lordosis, or contraction of the lumbar spine.
This is when the business cycle starts to turn from contraction into an expansion.
For example, if the contraction portion of the business cycle is severe enough, there would be a label for a recession occurring.
On the other hand, in times when the business is struggling, it can be in a period of contraction or even trough.
If the company owes money, it is in a contraction period.
Sodium also regulates blood volume and blood pressure, transmits impulses for muscle contraction and nerve function, and regulates the acid balance in the blood and body fluids.
The effects are an increase in stroke volume or the amount of blood flow caused by a single contraction of the left ventricle.
Slowly curl your torso up, lifting your hips off the pad and hold in the max contraction position for as long as possible.
Grab the bar and roll it from the tips of your fingers (almost open hands) to full contraction (closed fist).
Place a dumbbell in that hand give it a good stretch at the bottom, followed by a full contraction.
When someone says that they are performing isotonic exercise, it means that they are performing an exercise that involves muscle contraction against a constant load.
In contrast, a muscle that begins to lengthen as it contracts is called an eccentric contraction.
This is not so much a power movement as one using full contraction.
The concentric phase of a muscular contraction occurs when a muscle is shortening.
Since a muscle is lengthening as it contracts during eccentric contraction, this type of training gives the muscles that long lean look.
Curl the weight up to full contraction while twisting the hand so the knuckles face the floor at the top.
Yet another intensity-boosting trick is to do burns, i.e. partial reps for the 30% or so toughest part in the middle, where you do four to five extra reps without going to full extension or contraction.
It also makes them more "springy" in that they get more efficient at rapid contraction, as in the case of jumping or tossing something, for example.
Hold the contraction for about 20 seconds.
This causes a deeper abdominal contraction.
Since most sport and exercise injuries occur during the muscle's normal range of contraction, increasing the joint's range of motion will not decrease the risk of injury.
The process of warming up prepares your muscles for peak performance in contraction and extension.
This type of exercise allows you to maintain a fixed position for maximum contraction.
Inhale to prepare, and as you exhale, draw your navel to your spine, and hold an abdominal contraction for 10 seconds.
Using your abdominal muscles, lift through the chest until you feel a contraction in your abs, and then lower yourself back down.
When you move the muscles in your body, you perform some type of a muscle contraction.
When you actively hold a muscle contraction at a fixed length, it is known as an isometric contraction.
This is a type of isometric contraction.
If you are sitting in a chair and you squeeze your gluteal muscles together and hold them, you have also performed an isometric contraction.
The word "tonic" means characterized by continuous contraction of muscle, while the prefix "iso" means fixed.
Therefore, an isotonic contraction means fixed continuous contraction.
The act of lifting weights causes muscle contraction through flexion (shortening or pulling) and extension (lengthening and pushing).
When you perform a plank to work your abs, you're pressing against the ground with your forearms and toes to hold your full-body contraction in place.
Tu is shortened to t' because in French, when two words come together with the first ending in a vowel and the second beginning with a vowel, a contraction is used.
It takes only a little bit more effort to figure out the negative contraction, "n'est" which means "is not"--the negation is double in French.
The drug can also help with dystonia, a severe contraction of muscles in the shoulder and neck.
But that lasted no more than a few minutes before the doe dropped to the ground and strained with another contraction.
In addition, the communes have a right to levy a, surtax not exceeding 50% of the quota levied by the state upon lands and buildings; a family tax, or fuocatico, upon the total incomes of families, which, for fiscal purposes, are divided into various categories; a tax based upon the rent-value of houses, and other taxes upon cattle, horses, dogs, carriages and servants; also on licences for shopkeepers, hotel and restaurant keepers, &c.; on the slaughter of animals, stamp duties, one-half of the tax on bicycles, &c. Occasional sources of interest are found in the sale of communal property, the realization of communal credits, and the contraction of debt.
Further, although iron lengthens in fields of moderate strength, it contracts in strong ones; and if the wire is stretched, contraction occurs with smaller magnetizing forces than if it is unstretched.
The contraction of the diffraction pattern with increase of aperture is of fundamental importance in connexion with the resolving power of optical instruments.
With these latter glasses there is, of course, considerable risk that the partial fusion and consequent contraction of the fireclay of the crucible may result in its destruction and the entire loss of the glass.
The end wall is usually very thin, and the protoplasm on artificial contraction commonly sticks to it just as in a sieve-tube, though no perforation of the wall has been found.
A second contraction may take place later, immediately preceding the segmentation of the thread.
The blood is probably circulated by the general contraction of the whole animal, since it is very doubtful if there are any intrinsic muscles in the vessel-walls.
By the waves of contraction executed by the proboscis accompanied by inflation of the collar, progression is effected, sometimes with marvellous rapidity.
Minute cracks are sometimes produced by the contraction; they are often more or less straight, but in other cases a very perfect system of rounded fissures arises.
It appears that the contraction which followed the initial extension of the iron reached a limit in fields of i 000 or 1100.
Hence the changes of volume undergone by a given sample of wrought iron under increasing magnetization must depend largely upon the state of the metal as regards hardness; there may be always contraction, or always expansion, or first one and then the other.
Taylor Jones showed in 1897 that only a small proportion of the contraction exhibited by a nickel wire when magnetized could be accounted for on Kirchhoff's theory from the observed effects of pulling stress upon magnetization; and in a more extended series of observations Nagaoka and Honda found wide quantitative divergences between the results of experiment and calculation, though in nearly all cases there was agreement as to quality.
The whole of the rod will therefore be subject to a compressive longitudinal stress P, the associated contraction R, expressed as a fraction of the original length, being R = P/M = (B 2 -H2)/87-M, where M is Young's modulus.
The wire is subject to two superposed magnetizations, the one longitudinal, the other circular, due to the current traversing the wire; the resultant magnetization is consequently in the direction of a screw or spiral round the wire, which will be right-handed or left-handed according as the relation between the two magnetizations is right-handed or left-handed; the magnetic expansion or contraction of the metal along the spiral lines of magnetization produces the Wiedemann twist.
With n=1, the re-entrant walls are given of Borda's mouthpiece, and the coefficient of contraction becomes 2.
But Wellhausen 1 is probably right in taking the word as a contraction for Hagariah ("Yahweh hath girded"), just as Zaccai (Zacchaeus) is known to be a contraction of Zechariah.
This regulation of turgor is as characteristic of vegetable protoplasm as contraction is of muscle.
The rotation of the planets on their axes is also explained as a consequence of the nebular theory, for at the time of the first formation of the planet it must have participated in the rotation of the whole nebula, and by the subsequent contraction of the planet the speed with which the rotation was performed must have been accelerated.
The sun is thus slowly contracting; but as it contracts it gains heat by the operation of the law just referred to, and thus the further cooling and further contraction of the sun is protracted until the additional heat obtained is radiated away.
This is an inappreciable distance when compared with the diameter of the sun, which is nearly a million of miles, but the significance for our present purpose depends upon the fact that this contraction is always taking place.
Burra is a contraction of Bo?gar-oy, meaning "Broch island."
In weak fields the magnetic contraction is always diminished by pulling stress; in strong fields the contraction increases under a small load and diminishes under a heavy one.
Of these there were three possible forms - (1) relaxation, (2) contraction of the minute passages or ropoc, and (3) a mixed state, partly lax, partly constricted.
He had discovered a contraction in the vein of fluid (vena contracta) which issued from the orifice, and found that, at the distance of about a diameter of the aperture, the section of the vein was contracted in the subduplicate ratio of two to one.
Many observers hold the view that the chromosomes are pulled apart by the contraction of the fibres to which they are attached.
They assist in the extremely rapid and vigorous ventilation of the lungs, the latter being capable of but very limited expansion and contraction in birds.
This soil is spongy, and, undergoing alternate contraction and expansion from being alternately comparatively dry and saturated with moisture, allows the heavy blocks to slip down by their own weight into the valley, where they become piled up, the valley stream afterwards removing the soil from among and over them.
The effect of such contraction would be to draw the materials of the ring into a single mass, and thus we would have a planet formed, while the satellites of that planet would be developed from the still nascent planet in the same way as the planet itself originated from the sun.
As the sun loses heat it contracts, and every pair of particles in the sun are nearer to each other after the contraction than they were before.
An important distinction separates true mixed crystals and crystallized double salts, for in the latter the properties are not linear functions of the properties of the components; generally there is a contraction in /10.591 volume, while the re fractive indices and other physical properties do not, in general, obey the additive law.
By the contraction of the valves the small smooth seeds, which form FIG.