(a.) Indistinctly crystalline; -- applied to rocks and minerals, whose state of aggregation is so fine that no distinct particles are visible, even under the microscope.
Example Sentences:
Pinite
Definition:
(n.) A compact granular cryptocrystalline mineral of a dull grayish or greenish white color. It is a hydrous alkaline silicate, and is derived from the alteration of other minerals, as iolite.
(n.) Any fossil wood which exhibits traces of having belonged to the Pine family.
(n.) A sweet white crystalline substance extracted from the gum of a species of pine (Pinus Lambertina). It is isomeric with, and resembles, quercite.
Example Sentences:
(1) Delta Pinit is thought to principally reflect the resistance of the pulmonary airways Raw.
(2) Baltic amber is a fossil resin deposited 36-7 million years ago and one source may be the extinct tree Pinites (Pinus) succinifer.
(3) Delta Pinit has been taken to equal the pressure drop across the pulmonary airways, possibly with a contribution from the tissues of the respiratory system.
(4) Despite the introduction of significant mechanical heterogeneities, delta Pinit still reflected the pressure drop as the result of the resistance of the conducting airways.
(5) Steady-state resistance calculated from the sum of delta Pinit and delta Pdiff was similar to airway resistance calculated from delta Pinit alone.
(6) 65: 408-414, 1988) that in open-chest mongrel dogs, under control conditions, the initial rapid pressure change (delta Pinit) reflects conducting airway resistance and the subsequent gradual pressure change (delta Pdif) reflects stress recovery of the tissues.
(7) The physiological interpretations of delta Pinit and delta Pdif have been somewhat unclear.
(8) The first phase is a very rapid jump, designated delta Pinit, which occurs immediately on interruption of flow.
(9) We found that, in the absence of the chest wall, delta Pinit reflects only the resistance of the airways and that delta Pdif can be ascribed almost entirely to the stress recovery properties of lung tissues.
(10) In all studies, airway pressure rose to equilibrate with alveolar pressure immediately after the interruption (delta Pinit) regardless of increases in airway resistance.
(11) A Moody plot (the Friction coefficient calculated using delta Pinit versus the Reynolds number) had a marked negative slope at Reynolds numbers up to 5 x 10(4), whereas the plot is predicted to have a slope close to zero at Reynolds numbers greater than 4 x 10(3) on the basis of purely fluid dynamic considerations.
(12) The second phase is designated delta Pdif and is a further pressure change in the same direction as delta Pinit but evolving over several seconds.
(13) In the present study we attempted to separate the contributions of airways and tissues to delta Pinit in intact dogs by performing flow interruptions with the lungs full of gas mixtures having different physical properties.
(14) If the flow of gas at the airway opening of a tracheostomized dog is suddenly interrupted during expiration, the airway pressure exhibits a sudden very rapid rise, called delta Pinit, which has been shown previously to equal the resistive pressure drop across the airways in open-chest dogs, and to have a significant additional contribution from the tissues of the chest wall in intact dogs.
(15) Since previously used methods for measuring respiratory system resistance have employed varying combinations of delta Pinit and delta Pdif as the resistive pressure drop, it is clear that measurements of resistance must be made with standard techniques under standard conditions if they are to be compared.
(16) Following airway occlusion one generally sees a rapid change in airway opening pressure, Pinit, which reflects the resistive pressure drop across the system, followed by a secondary, slower pressure change, Pdif, which reflects the tissue visco-elastic properties together with any redistribution of gases occurring between lung units at different pressure at the time of interruption.
(17) delta Pdif became larger than delta Pinit towards the end of expiration.
(18) In general, the pressure signal obtained exhibits an initial rapid change (delta Pinit) accompanied by rapid damped oscillations, followed by a further slow change to a steady-state plateau level.
(19) We used the interrupter technique to measure the resistance Rinit (equal to the initial change delta Pinit in tracheal pressure divided by flow at interruption) during expiration in six normal anaesthetized-paralyzed cats.
(20) Assuming delta Pinit to be the result of a linear dependence of airway resistance on flow and a constant tissue resistance, we were able to account for the negative slope of the Moody plot.