What's the difference between libration and variation?

Libration


Definition:

  • (n.) The act or state of librating.
  • (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.

Variation


Definition:

  • (n.) The act of varying; a partial change in the form, position, state, or qualities of a thing; modification; alternation; mutation; diversity; deviation; as, a variation of color in different lights; a variation in size; variation of language.
  • (n.) Extent to which a thing varies; amount of departure from a position or state; amount or rate of change.
  • (n.) Change of termination of words, as in declension, conjugation, derivation, etc.
  • (n.) Repetition of a theme or melody with fanciful embellishments or modifications, in time, tune, or harmony, or sometimes change of key; the presentation of a musical thought in new and varied aspects, yet so that the essential features of the original shall still preserve their identity.
  • (n.) One of the different arrangements which can be made of any number of quantities taking a certain number of them together.

Example Sentences:

  • (1) The variation in thickness of the LLFL may modulate the species causing damage to the cells below it.
  • (2) There was appreciable variation in toothbrush wear among subjects, some reducing their brush to a poor state in 2 weeks whereas with others the brush was rated as "good" after 10 weeks.
  • (3) Correction for within-person variation in urinary excretion increased this partial correlation coefficient between intake and excretion to 0.59 (95% CI = 0.03 to 0.87).
  • (4) The coefficient of variation in the integrated area of a single peak is 16%.
  • (5) Sequence variation in the gp116 component of cytomegalovirus envelope glycoprotein B was examined in 11 clinical strains and compared with variation in gp55.
  • (6) Effects of habitual variations in napping on psychomotor performance, short-term memory and subjective states were investigated.
  • (7) A small variation in T1 was found between older (greater than 40 years) and younger (less than 40 years) subjects, but no such effect was observed in the case of T2.
  • (8) The variation of the activity of the peptidase with pH in the presence of various inhibitors was investigated in both control and insulted muscle fibres.
  • (9) This study examined both the effect of variations in optical fiber tip and in light wavelength on laser-induced hyperthermia in rat brain.
  • (10) = 19) with a very low, but statistically significant, correlation with the AUC, r = 0.35 (p less than 0.05), thus demonstrating a very great individual variation in sensitivity to cimetidine.
  • (11) Once the normal variations are mastered, appreciation of retinal, choroidal, optic nerve, and vitreal abnormalities is possible.
  • (12) Regression analysis on the 21 clinical or laboratory parameters studied showed that the only variable independently associated with CSF-FN was the total protein concentration in the CSF; this, however, explained only 14% of the observed variation in the CSF-FN concentration and did not show any correlation with CNS involvement.
  • (13) Pharmacokinetic parameters, such as these clearances, had large intersubject variations.
  • (14) Variability (CV = 0.7%) in body volume of a 45-year-old reference man measured by SH method was very similar to variation (CV = 0.6%) in mass volume of the 60-1 prototype.
  • (15) Further analysis of the role of sex steroid hormones is required in view of the sex variations reported.
  • (16) The overall result of this system has been to decrease the coefficients of variation to below 5% for all the milk and serum proteins tested.
  • (17) The variation in age-specific rates with age was similar for all cancers, as demonstrated by large positive correlation coefficients between age-incidence patterns averaged over all populations.
  • (18) Even though there are variations among equipment bearing the same model number it was considered worthwhile to make available relative cavitational and temperature data.
  • (19) Accordingly, LPA proved an extremely stable characteristic which did not show any substantial variations in the course of five years.
  • (20) Variation in patient mix was a major determinant of the large variations in resource use.