scholarly journals Normal fluctuations and the FKG inequalities

1980 ◽  
Vol 74 (2) ◽  
pp. 119-128 ◽  
Author(s):  
C. M. Newman

A continuous record of the ionization current produced by cosmic rays in an ionization chamber shows, if the recording apparatus is sufficiently sensitive, occasional relatively large momentary currents superposed on the normal fluctuations. These large momentary currents are generally called “bursts”. They were first discovered by Hoffmann. It has often been assumed that the bursts are of the same nature as the showers which are observed either in the Wilson chamber or by means of three or more coincidence counters; but so far no conclusive evidence, particularly for the larger bursts, has been reported in support of this assumption.


1998 ◽  
Vol 274 (5) ◽  
pp. E920-E927 ◽  
Author(s):  
Sarah Page ◽  
Michael Salem ◽  
Maren R. Laughlin

13C- and31P-NMR were used in methylene blue-treated human erythrocytes to determine the dependence on intracellular Mg2+concentration ([Mg2+]i) of the pentose phosphate pathway (PPP), the glycolytic pathway, and adenine nucleotide synthesis. The PPP flux had an [Mg2+]iat half-maximal velocity ([Mg2+]i,0.5) of 0.02 mM, well below the physiological range (0.2–0.7 mM). Flux through the PPP was reduced at higher [Mg2+]ias flux through phosphofructokinase was increased ([Mg2+]i,0.5= 0.16 mM). [Mg2+]i,0.5of phosphoglycerate kinase flux, which equals net ADP phosphorylation rate, was 0.27 mM, well within the physiological [Mg2+]irange. The rate of adenine nucleotide synthesis from [2-13C]glucose-derived ribose 5-phosphate and exogenous adenine also exhibited dependence on [Mg2+]ibut was not saturable up to 1.6 mM. Therefore, net flux through the PPP and glycolytic pathways in erythrocytes is not strongly dependent on [Mg2+]iat physiological ion concentrations, but both ADP phosphorylation and adenine nucleotide synthesis are likely to be regulated by normal fluctuations in [Mg2+]i.


1974 ◽  
Vol 15 (7) ◽  
pp. 998-999 ◽  
Author(s):  
James L. Monroe

2002 ◽  
Vol 1 (2) ◽  
pp. 131-137 ◽  
Author(s):  
Debra K. Moser ◽  
Susan K. Frazier ◽  
Mary A. Woo ◽  
Linda K. Daley

Background: One barrier to accurate interpretation of changes in hemodynamic pressures and cardiac output is lack of data about what constitutes a normal fluctuation. Few investigators have examined normal fluctuations in these parameters and none have done so in patients with left ventricular dysfunction. Aims: To describe normal fluctuations in pulmonary artery pressures and cardiac output in patients with left ventricular dysfunction. Methods: Hemodynamically stable advanced heart failure patients ( N=39; 55±6 years old; 62% male) with left ventricular dysfunction (mean ejection fraction 22±5%) were studied. Cardiac output and pulmonary artery pressures were measured every 15 min for 2 h. Results: Mean±standard deviation fluctuations were as follows: pulmonary artery systolic pressure=7±4 mmHg; pulmonary artery diastolic pressure=6±3 mmHg; pulmonary capillary wedge pressure=5±3 mmHg; cardiac output=0.7±0.3 l/min. The coefficient of variation for fluctuations in pulmonary artery systolic pressure was 6.7%, in pulmonary artery diastolic pressure was 9.3%, in pulmonary capillary wedge pressure was 9.2%, and in cardiac output was 7.2%. Conclusions: Values that vary <8% for pulmonary artery systolic pressure, <11% for pulmonary artery diastolic pressure, <12% for pulmonary capillary wedge pressure, and <9% for cardiac output from baseline represent normal fluctuations in these parameters in patients with left ventricular dysfunction.


1997 ◽  
Vol 273 (5) ◽  
pp. H2325-H2332 ◽  
Author(s):  
Dustan A. Barber ◽  
Virginia M. Miller

Experiments were designed to determine whether normal fluctuations in endogenous sex steroid hormones and/or gender affect endothelium-dependent relaxations in coronary arteries, and, if so, to identify endothelium-derived factors contributing to these differences. Coronary arteries from sexually mature, gonadally intact male and female pigs or ovariectomized pigs were prepared either for study of isometric force in organ chambers or for measurement of prostanoids and activity of nitric oxide (NO) synthase. In organ chamber studies, neither the magnitude nor the sensitivity of endothelium-dependent relaxations correlated with endogenous estrogen or progesterone in female pigs. However, relaxations to bradykinin and UK-14304 were significantly greater and/or shifted leftward in arterial rings from female compared with male pigs. Indomethacin (10−5 mol/l) increased endothelium-dependent relaxations only in arteries from male pigs. N G-monomethyl-l-arginine reduced endothelium-dependent relaxations to a similar extent in coronary arteries from either sex. Neither production nor response to thromboxane A2 or prostacyclin differed in coronary arteries from male compared with female pigs. Activity for calcium-dependent or -independent NO synthase was similar in both sexes. These results suggest that normal fluctuations in endogenous sex steroid hormones do not affect endothelium-dependent relaxations in coronary arteries from female pigs. There are, however, gender differences in endothelium-dependent relaxations that are indomethacin sensitive and may be due to cyclooxygenase products other than thromboxane A2 or prostacyclin.


Author(s):  
T. R. Galimzyanov ◽  
M. A. Kalutsky ◽  
O. V. Kondrashov ◽  
K. V. Pinigin ◽  
R. J. Molotkovsky ◽  
...  

2009 ◽  
Vol 09 (01) ◽  
pp. 81-100 ◽  
Author(s):  
HENK BRUIN ◽  
MIKE TODD

We prove that multimodal maps with an absolutely continuous invariant measure have exponential return time statistics around almost every point. We also show a "polynomial Gibbs property" for these systems, and that the convergence to the entropy in the Ornstein–Weiss formula has normal fluctuations. These results are also proved for equilibrium states of some Hölder potentials.


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