rotation

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rotation

 [ro-ta´shun]
1. the process of turning around an axis.
2. in obstetrics, the turning of the fetal head (or presenting part) for proper orientation to the pelvic axis. It should occur naturally, but if it does not it must be accomplished manually or instrumentally by the obstetrician or manually by the nurse-midwife.
3. a clinical assignment for students in a specific clinical area.
4. in dentistry, the turning of a malturned tooth into its proper position.
pelvic rotation movement of the pelvis around an imaginary axis.
site rotation the selection of sequential injection locations for a patient receiving multiple injections. A chart is frequently utilized to guide the nurse in rotating sites so that the same location is not used repeatedly, which would lead to tissue damage and irregular absorption of drugs.

ro·ta·tion

(rō-tā'shŭn),
1. Turning or movement of a body around its axis.
2. A recurrence in regular order of certain events, such as the symptoms of a periodic disease.
3. In medical education, a period of time on a particular service or specialty.
[L. rotatio, fr. roto, pp. rotatus, to revolve, rotate]

rotation

/ro·ta·tion/ (ro-ta´shun) the process of turning around an axis. In obstetrics, the turning of the fetal head (or presenting part) for proper orientation to the pelvic axis.ro´taryro´tatory
optical rotation  the quality of certain optically active substances whereby the plane of polarized light is changed, so that it is rotated in an arc the length of which is characteristic of the substance.
van Ness rotation  fusion of the knee joint and rotation of the ankle to function as the knee; done to correct a congenitally missing femur.

rotation

[rōtā′shən]
Etymology: L, rotare
1 the gyration of a bone around its central axis, one of the four basic movements allowed by the various joints of the skeleton. The central axis may lie in a separate bone, as in the pivot formed by the dens of the axis around which the atlas turns. Some bones, such as the humerus, rotate around their own longitudinal axis. Alternatively, the axis of rotation may not be quite parallel to the long axis of the rotating bone, as in movement of the radius on the ulna during pronation and supination of the hand. Compare angular movement, circumduction, gliding.
2 a turning around an axis.
3 the turning of the fetal head to descend through the pelvis during birth.
enlarge picture
Upward rotation

rotation

Movement around an axis Graduate education A period of time during which a medical student, or a physician in an early period of his training works in a particular service. See Audition rotation, Clinical rotation, Extern, Intern Obstetrics The turning of a fetus around its long axis such that the presenting part changes. See External rotation, Internal rotation, Limb rotation.

ro·ta·tion

(rō-tā'shŭn)
1. Turning or movement around an axis.
2. A recurrence in regular order of certain events, such as the symptoms of a periodic disease.
3. In medical education and other health education progams, a period of time dedicated to a particular service or specialty.
4. Practice of changing hours worked periodically; shift work.
[L. rotatio, fr. roto, pp. rotatus, to revolve, rotate]

rotation

movement of a body or object about an axis. The axis may be external (e.g. gymnastic high bar) or within the body (e.g. at a joint). May be combined with translation to give general motion.

rotation

limb/body part motion about its longitudinal axis

rotation,

n circular movement of a bone around its own axis.
Lateral and
medial rotation are directional referents.
Upward and
downward rotation refer only to the scapulae.

ro·ta·tion

(rō-tā'shŭn)
Turning or movement of a body around its axis.
[L. rotatio, fr. roto, pp. rotatus, to revolve, rotate]

rotation,

n 1. the act of turning about an axis or a center.
n 2. movement of a tooth around its longitudinal axis.
rotation center,

rotation

a state of having been pivoted around an axis. See also torsion, rotational.

rotation flap graft
see pedicle graft.
rotation fork
an obstetrical instrument used in mares and cows. A 3 ft long rod with a crossbar handle and a two-pronged fork at the other end. The prongs have eyelets to which cord or canvas hobbles are attached. Two presenting limbs are threaded through these and the instrument pushed into the uterus to the body. Rotation of the bar handle helps to rotate the calf or foal, or uterus if it is closely applied. See also cammerer rotation fork.
pedal rotation
see pedal bone rotation.
rotation programs
alternation of crops (crop rotation), of grazing of pastures (paddock or field rotation), of bulls or rams running with breeding females (bull rotation), of anticoccidial agents to poultry or anthelmintics to sheep to avoid the development of resistance to the medication by the target organism. Rotational grazing of pastures is beneficial to pasture growth when livestock concentration is high, and aids in the control of helminth parasites by interrupting their life cycles.
References in periodicals archive ?
To test plant response to different soil treatments including preplant crop rotation, researchers established soil microplots by installing 4-foot lengths of 24-inch-diameter concrete pipe vertically into the soil and filling the pipes with soil from a nearby orchard affected with Prunus replant disease.
Total soil C showed significant differences between treatments, with total C contents increasing in the order: continuous wheat = crop rotation < crop-pasture rotation = annual pasture < perennial pasture (Table 3).
Crop rotations appeared to have a greater effect on Po fractions than did tillage, but these were not significant.
This is a unique study of the effects of climate change on three crop rotations.
GM might help with 'no till' farming (sowing the seed directly into the ground without ploughing, so reducing damage to the soil structure), which allows for better crop rotation.
In addition to yield, studies on tong-term residual effects of crop rotations most commonly report soil properties such as aggregate stability, quality, and quantity of soil organic matter and its various fractions, nitrogen balance, and ecological and crop health issues such as weed seed banks, nematode and disease incidence, and herbicide impacts (Granatstein et al.
To date, the experiments have shown that in addition to soil water saved and increases in yields and economics, there are substantial improvements to soil with alternative crop rotations.
Among the techniques that the Institute has demonstrated will control weeds as well or better than chemical herbicides are crop rotations, cover crops like legumes between rows, and properly mechanical methods like mowing and plowing.
TAWC includes 3,954 acres of land farmed various ways--with and without crop rotations, with integration of livestock and crop production, and with various forms of irrigation.
Most common practices are, in order, residue management, crop rotations, grassed waterways, contour farming and terraces.
They're using WholeFarm, a model originally designed by ARS scientists to assess crop rotations, commodity prices, yields, and profits.
Duggar starts a cotton experiment near the Alabama campus to try to prove that sustainable cotton production could be achieved in the state if farmers used crop rotations that included legume cover crops in winter.