(n.) A real or apparent libratory motion, like that of a balance before coming to rest.
Example Sentences:
(1) The simulation reproduces the amplitudes of the fast librational motions of the backbone N-H bonds determined from 15N nuclear magnetic relaxation data, as well as the crystallographic B-factors.
(2) This has provided information on the translational and librational motions of individual groups in the complex.
(3) Above about 52 degrees C cholesterol improves the order by decreasing the amplitude of the librational motions.
(4) In its thermal vibrations, the adenosine molecule behaves as two rigid segments with a torsional libration about the glycosidic bond of 14.4 deg2 at 123 K. The force constant for this libration, as determined from the diffraction data, is 73 (10) J mol-1 deg-2.
(5) In the 1970s, Princeton physicist Gerald K O’Neill envisioned 100,000-person colonies, stationed at what is known as the fifth Lagrangian libration point (L5) in the moon’s orbit – like a gravitational eddy where things stay put by themselves.
(6) The source of the entropic elastomeric force is demonstrated to be the result of internal chain dynamics, and the mechanism is called the librational entropy mechanism of elasticity.
(7) The librational motions are to some extent cooperative.
(8) A translational, librational, and screw analysis of the thermal parameters of endothiapepsin also supports a model in which the two parts can move relative to each other.
(9) Collectively these results suggest that hydrophobic interactions make contributions to elastin entropy at low extensions, but that librational mechanisms make larger contributions to the elastic restoring force at longer extensions.
(10) Many such motions reflect peptide plane librations that result from anticorrelated crankshaft rotations of psi i and phi i+1.
(11) 7 nsec at 40 degrees C) where the band has been assigned to a peptide librational mode.
(12) The amplitude of the base motion, modeled as a fast four-site libration, or diffusion in a cone, increased slightly with higher levels of hydration.
(13) The TLS model has also been applied to the whole protein molecule and shows that the average motion is approximately isotropic with little librational character.
(14) Calculations of the relative statistical weights of these conformations confirm earlier theoretical considerations on the importance of the librational free energy of stable conformations of peptides.
(15) Since the spin-lattice relaxation rate for the active R-state (immobilized) phosphate is similar to that observed in other phosphoenzymes of different size it is suggested that a librational motion on the nanosecond time scale may constitute a common spin-lattice relaxation pathway for phosphates in macromolecules.
(16) The absorption bands of the glycerol ester, phosphoryl, and choline groups were broadened upon hydration, suggesting the activation of the librational or torsional motion.
(17) The similarity of Raman frequencies for B-, A-, C-, and Z-DNA suggests that these modes originate from concerted motions of the bases (librations), which are not strongly dependent upon helix backbone geometry or handedness.
(18) Thus, while the rate of these transitions cannot be quantified, the simulated decay of these correlation functions is completely consistent with the physical picture in which the N-H vectors, in addition to fast librational motion, undergo large amplitude jumps between conformations stabilized by hydrogen bonds.
(19) By analogy this allows for the first assignment of a peptide librational mode in a naturally occurring polypeptide or protein.
(20) The hydrophobic side groups in the protein core show mainly translational motion, with mean-square librations of 20 deg2 which are similar to those found in some close-packed crystals of small organic molecules.
Vibration
Definition:
(n.) The act of vibrating, or the state of being vibrated, or in vibratory motion; quick motion to and fro; oscillation, as of a pendulum or musical string.
(n.) A limited reciprocating motion of a particle of an elastic body or medium in alternately opposite directions from its position of equilibrium, when that equilibrium has been disturbed, as when a stretched cord or other body produces musical notes, or particles of air transmit sounds to the ear. The path of the particle may be in a straight line, in a circular arc, or in any curve whatever.
Example Sentences:
(1) The Cavitron Ultrasonic Surgical Aspirator (CUSA) is a dissecting system that removes tissue by vibration, irrigation and suction; fluid and particulate matter from tumors are aspirated and subsquently deposited in a canister.
(2) In order to control noise- and vibration-caused diseases it was necessary not only to improve machines' quality and service conditions but also to pay special attention to the choice of operators and to the quality of monitoring their adaptation process.
(3) The intensity changes seen for alpha-fucose were found to follow a reversible first-order rate-equation and the rate constants obtained from different vibrational bands were found to be consistent among themselves and in reasonable agreement with those obtained by other techniques.
(4) Amplitude of the musical vibrations decreased by inhalation of amyl nitrite, but increased by infusion of methoxamine.
(5) The response of isolated muscle tissue of white rats to low-frequency vibration has been studied.
(6) The "random coil" conformational problem is examined by comparison of vibrational CD (VCD) spectra of various polypeptide model systems with that of proline oligomers [(Pro)n] and poly(L-proline).
(7) Headache and vertigo were not linked with exposure to vibration in forestry and a significant part of the numbness reported may be due to the carpal tunnel syndrome.
(8) Additionally, by ultrasonic vibration of tissues that had been subjected to prolonged osmium fixation, the epithelium was removed and such microdissected membranes similarly were examined.
(9) The ability of a mathematical model to evaluate the effects of two different pain modulating procedures (partial nerve block and vibration) on acute experimental pulpal pain was studied.
(10) The only likely cause for the pathological vascular findings in our patient was an exposure to vibration due to excessive off-street motorcycle driving.
(11) Time-resolved infrared spectroscopy with 0.5-ps resolution is used to track the evolution of the CO stretching vibration after visible photoexcitation of carboxyhemoglobin in water at room temperature.
(12) Biodynamic stressors such as acceleration, vibration, heat, and cold can affect pilot performance.
(13) There have been shown many changes, which took place in the various anatomic-physiological formations of the brain, and evaluated their significance in organism's responses to the effects of ionizing and nonionizing radiation, hyperoxia, hypoxia, accelerations, vibrations and combined effects of some of those factors.
(14) Tetrapolar rheovasography was used to medically examine 54 riveters, of equal age and duration of work, who were exposed to the complex action of low-intensity vibration and noise.
(15) A vibration-rotation-tunneling band of the perdeuterated cluster has been measured near 89.6 wave numbers by tunable far infrared laser absorption spectroscopy.
(16) Vibratory sensitivity was strongly related to height when measurements were made with either the vibration sensitivity tester (P = .02) or the biothesiometer (P less than .01); however, there was no relation between thermal sensitivity (as measured with the thermal sensitivity tester) and height.
(17) Our experiments with monkeys gave typical resonance curves for the transmission of vibration of the bulbi with maxima between 25 and 31.5 Hz.
(18) Altering the frequency of vibration did not alter the distribution of tremor frequencies.
(19) Superficial cutaneous stimulation of the dorsal side of the forearm during tendon vibration noticeably decreased the P1 peaks in both types of motor units.
(20) A survey is given of the literature on the sensitivity of the vestibular system to audio-frequency sound and vibration in animals.