Quantitative Formation Permeability Evaluation from Stoneley Waves

Author(s):  
A. Brie ◽  
T. Endo ◽  
D.L. Johnson ◽  
F. Pampuri
2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1067.1-1067
Author(s):  
S. Hecquet ◽  
P. Totoson ◽  
H. Martin ◽  
C. Prati ◽  
D. Wendling ◽  
...  

Background:Growing evidence argue for a role of the gut in the pathophysiology of various chronic rheumatic diseases such as spondyloarthritis (SpA). This so-called “gut-joint axis” involves dysbiosis, bacterial translocation, intestinal inflammation and increase in intestinal permeability. Recent data from clinical and basic research suggested that the integrity of the intestinal barrier might be a key determinant in translating autoimmunity to inflammation, making intestinal permeability a potential marker or a target for future therapies.Objectives:To analyse the available data on intestinal permeability in SpA patients and the effects of drugs such as non-steroidal anti-inflammatory drugs (NSAIDs) on intestinal permeability.Methods:A systematic review was conducted. Without date restriction, the following databases were searched through September 1, 2020: Medline, Embase and Cochrane. Studies with patients with SpA assessing the intestinal permeability were selected. Some of the included studies have assessed the effect of NSAIDs on intestinal permeability.Results:A total of 12 studies were included in the final analysis. The 12 studies involved a total of 268 SpA patients, including 240 ankylosing spondylitis (AS). Among the studies included, four studies used the lactulose/mannitol test, four studies used the 51Cr-ethylenediaminetetraacetic test and two studies used the polyethylene glycols test. Nine of the 12 studies reported increased intestinal permeability regardless on the method used for intestinal permeability evaluation. Four studies evaluated the link between disease activity, assessed by CRP and ESR levels, and intestinal permeability and showed no correlation between increased intestinal permeability and markers of disease activity in AS patients. As regards the effects of NSAIDs on intestinal permeability, data are controversial. Two studies, including one evaluating indomethacin, did not show any influence of NSAIDs in AS patients, one study showed an increase in intestinal permeability under NSAIDs in only 60% of the patients, another study reported increased intestinal permeability. When comparing the effect of NSAIDs in patients with AS to healthy subjects, one study reported a comparable NSAIDs-induced increase in intestinal permeability in both groups.Conclusion:The results of our review suggest that increased intestinal permeability is present in SpA patients even in the absence of NSAIDs use and regardless of the method used to assess intestinal permeability. The effects of NSAIDs on intestinal permeability in SpA patients is more controversial and further studies are needed to clarify them.Disclosure of Interests:None declared


1990 ◽  
pp. 261-269
Author(s):  
Shigeo KAND ◽  
Akira TAMADA ◽  
Shinjirou URAYAMA ◽  
Kazuo KERA

1984 ◽  
Vol 32 (3) ◽  
pp. 349-356 ◽  
Author(s):  
A.R. Thölén

1963 ◽  
Vol 53 (3) ◽  
pp. 483-501 ◽  
Author(s):  
Leonard E. Alsop

Abstract Periods of free vibrations of the spheroidal type have been calculated numerically on an IBM 7090 for the fundamental and first two shear modes for periods greater than about two hundred seconds. Calculations were made for four different earth models. Phase and group velocities were also computed and are tabulated herein for the first two shear modes. The behavior of particle motions for different modes is discussed. In particular, particle motions for the two shear modes indicate that they behave in some period ranges like Stoneley waves tied to the core-mantle interface. Calculations have been made also for a model which presumes a solid inner core and will be discussed in Part II. The two computer programs which were made for these calculations are described briefly.


2013 ◽  
Vol 59 ◽  
pp. 255-262 ◽  
Author(s):  
Tânia Viana ◽  
Sara Biscaia ◽  
Henrique A. Almeida ◽  
Paulo J. Bártolo

2015 ◽  
Vol 104 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Silvia Pescina ◽  
Paolo Govoni ◽  
Arianna Potenza ◽  
Cristina Padula ◽  
Patrizia Santi ◽  
...  

2011 ◽  
Vol 130 (1) ◽  
pp. EL44-EL49 ◽  
Author(s):  
Hanyin Cui ◽  
Jon Trevelyan ◽  
Sherri Johnstone

1964 ◽  
Vol 54 (5A) ◽  
pp. 1417-1427
Author(s):  
M. L. Ghosh

Abstract As an explanation for PF phase, the author has considered propagation of Stoneley waves along the inclined continental margin which constitutes the interface of liquid and solid media. An iterative process has been applied to find the displacement on the level surface. The results agree with observations of PF phase and it has been suggested that PF are probably Stoneley waves.


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