Pressure induced changes of renal flow resistance in the dog kidney in situ

1971 ◽  
Vol 325 (2) ◽  
pp. 95-102 ◽  
Author(s):  
K. Held ◽  
W. Niedermayer ◽  
J. Schaefer ◽  
H. J. Schwarzkopf ◽  
Ch. Weiss
Keyword(s):  
Flow Resistance ◽  
Dog Kidney ◽  
Renal Flow ◽  
Induced Changes

Rhythm effects on contractility of the beating isovolumic left ventricle

1960 ◽  
Vol 199 (6) ◽  
pp. 1115-1120 ◽  
Author(s):  
B. Lendrum ◽  
H. Feinberg ◽  
E. Boyd ◽  
L. N. Katz
Keyword(s):  
Heart Rate ◽  
Left Ventricle ◽  
Systolic Pressure ◽  
Ventricular Volume ◽  
Contractile Force ◽  
Postextrasystolic Potentiation ◽  
Pressure Development ◽  
Induced Changes ◽  
Electrical Alternans

Variation in contractile force of the isovolumic contracting left ventricle of the dog was studied in open-chested in situ hearts. The electrocardiogram and intraventricular pressures were recorded at various heart volumes. Spontaneous changes in heart rate and rhythm occurred at all volumes. Isovolumic systolic pressure development (contractile force) varied with rate and rhythm. Contractile force increased with heart rate (treppe) regardless of pacemaker origin. When a premature beat was followed by a compensatory pause, the premature beat showed a decrease and the next beat an increase in contractile force (postextrasystolic potentiation). The magnitude of the changes varied directly with the prematurity of the beat. Mechanical alternans was observed with electrical alternans, despite the absence of significant volume change. Rate-induced changes, postextrasystolic potentiation and mechanical alternans were additive when they occurred simultaneously. For practical purposes, ventricular volume (filling), hence muscle fiber length, remained constant during these rate and rhythm change, therefore could not affect the strength of contraction. Contractile force changes directly attributable to rate and rhythm changes do, therefore, occur in the intact mammalian heart.

Kinetics of alkali ion exchange of irradiated glasses

2003 ◽  
Vol 792 ◽  
Author(s):  
Michael I. Ojovan ◽  
William E. Lee
Keyword(s):  
Ion Exchange ◽  
External Irradiation ◽  
Glass Temperature ◽  
Ion Exchange Kinetics ◽  
Radiation Induced ◽  
Exchange Kinetics ◽  
Induced Changes ◽  
Kinetics Of ◽  
Alkali Ion

ABSTRACTThe kinetics of alkali ion exchange of irradiated glasses were investigated using the structural energy barrier model for ion exchange of glasses. Derived rates of alkali ion exchange depend both on irradiation dose D(Gy) and dose rate q(Gy/s) illustrating that some effects cannot be simulated by external irradiation and require in-situ measurements. Higher D and q lead to increased ion exchange rates. Significant changes occur in the activation energies demonstrating a 4 – 6 times decrease depending on glass composition. Radiation-induced changes are higher at relatively low temperatures and are diminished by increased glass temperature. Numerical estimations show that changes in alkali ion exchange kinetics occur at D far below damaging doses.

scholarly journals Effects of tidal volume and respiratory frequency on lung lymph flow

2005 ◽  
Vol 99 (2) ◽  
pp. 556-563 ◽  
Author(s):  
David B. Pearse ◽  
Robert M. Searcy ◽  
Wayne Mitzner ◽  
Solbert Permutt ◽  
J. T. Sylvester
Keyword(s):  
Tidal Volume ◽  
Lymphatic Vessels ◽  
Lymph Flow ◽  
Edema Formation ◽  
Fluid Filtration ◽  
Induced Changes ◽  
Lung Lymph ◽  
Lung Lymph Flow

Ventilation (V̇) increases lung lymph flow (Q̇l), but the separate effects of tidal volume (Vt) and frequency (f) and the role of V̇-induced changes in edema formation are poorly understood. An isolated, in situ sheep lung preparation was used to examine these effects. In eight sheep with f = 10 min−1, results obtained during 30-min periods with Vt = 5 or 20 ml/kg were compared with values obtained during bracketed 30-min control periods (Vt = 12.5 ml/kg). Eight other sheep with constant Vt (12.5 ml/kg) were studied at f = 5 or 20 min−1 and compared with f = 10 min−1. Three additional groups of six sheep were perfused for 100 min with control V̇ (10 ml/kg, 10 min−1). Vt was then kept constant or changed to 20 or 3 ml/kg during a second 100-min period. Increases in Vt or f increased Q̇l and vice versa, without corresponding effects on the rate of edema formation. For the same change in V̇, changing Vt had a greater effect on Q̇l than changing f. The change in Q̇l caused by an increase in Vt was significantly greater after the accumulation of interstitial edema. The change in Q̇l caused by a sustained increase in Vt was transient and did not correlate with the rate of edema formation, suggesting that V̇ altered Q̇l through direct mechanical effects on edema-filled compartments and lymphatic vessels rather than through V̇-induced changes in fluid filtration.

PCB-induced changes of a benthic community and expected ecosystem recovery following in situ sorbent amendment

2011 ◽  
Vol 30 (8) ◽  
pp. 1819-1826 ◽  
Author(s):  
Elisabeth M.-L. Janssen ◽  
Janet K. Thompson ◽  
Samuel N. Luoma ◽  
Richard G. Luthy
Keyword(s):  
Benthic Community ◽  
Ecosystem Recovery ◽  
Induced Changes

Beam-induced Changes of FePt Nanoparticles during STEM In-situ Annealing

2008 ◽  
Vol 14 (S2) ◽  
pp. 348-349 ◽  
Author(s):  
J Wittig ◽  
J Bentley ◽  
LF Allard ◽  
MS Wellons ◽  
C Lukehart
Keyword(s):  
New Mexico ◽  
Fept Nanoparticles ◽  
Induced Changes

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

scholarly journals Klar ensures thermal robustness of oskar localization by restraining RNP motility

2014 ◽  
Vol 206 (2) ◽  
pp. 199-215 ◽  
Author(s):  
Imre Gaspar ◽  
Yanxun V. Yu ◽  
Sean L. Cotton ◽  
Dae-Hwan Kim ◽  
Anne Ephrussi ◽  
...  
Keyword(s):  
Feedback Loop ◽  
Variable Temperature ◽  
Control Process ◽  
Gain Control ◽  
Protein Product ◽  
Posterior Pole ◽  
Dependent Manner ◽  
Messenger Ribonucleic Acid ◽  
Induced Changes

Communication usually applies feedback loop–based filters and amplifiers to ensure undistorted delivery of messages. Such an amplifier acts during Drosophila melanogaster midoogenesis, when oskar messenger ribonucleic acid (mRNA) anchoring depends on its own locally translated protein product. We find that the motor regulator Klar β mediates a gain-control process that prevents saturation-based distortions in this positive feedback loop. We demonstrate that, like oskar mRNA, Klar β localizes to the posterior pole of oocytes in a kinesin-1–dependent manner. By live imaging and semiquantitative fluorescent in situ hybridization, we show that Klar β restrains oskar ribonucleoprotein motility and decreases the posterior-ward translocation of oskar mRNA, thereby adapting the rate of oskar delivery to the output of the anchoring machinery. This negative regulatory effect of Klar is particularly important for overriding temperature-induced changes in motility. We conclude that by preventing defects in oskar anchoring, this mechanism contributes to the developmental robustness of a poikilothermic organism living in a variable temperature environment.

Contemplation of virally induced changes in salivary glands in Sjögren's syndrome: on the use of in situ hybridization in such studies

1989 ◽  
Vol 2 (4) ◽  
pp. 569-578 ◽  
Author(s):  
Riitta Keinänen ◽  
YrjöT. Konttinen ◽  
Margaretha Segerberg-Konttinen ◽  
Pertti Kemppinen ◽  
Markku Kulomaa ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Salivary Glands ◽  
Sjögren’S Syndrome ◽  
Sjögren's Syndrome ◽  
Sjogren’S Syndrome ◽  
Sjogren's Syndrome ◽  
Induced Changes ◽  
Sjögren‘S Syndrome
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