Release test with electromagnetic seismograph

1979 ◽  
Vol 23 (4) ◽  
pp. 322-332
Author(s):  
Vladimír Tobyáš ◽  
J. Buben
Keyword(s):  
Release Test ◽  
Electromagnetic Seismograph

The Clinical Usefulness of the Platelet Aggregation Test for the Diagnosis of Heparin-Induced Thrombocytopenia

1993 ◽  
Vol 69 (04) ◽  
pp. 344-350 ◽  
Author(s):  
B H Chong ◽  
J Burgess ◽  
F Ismail
Keyword(s):  
Platelet Aggregation ◽  
Heparin Therapy ◽  
Serotonin Release ◽  
Point System ◽  
Control Groups ◽  
Heparin Induced Thrombocytopenia ◽  
Heparin Concentration ◽  
Release Test ◽  
The Mean ◽  
Normal Controls

SummaryThe platelet aggregation test is widely used for the diagnosis of heparin-induced thrombocytopenia (HIT), a potentially serious complication of heparin therapy. We have evaluated its sensitivity and specificity in comparison with those of the 14C-serotonin release test. The sensitivity of the platelet aggregation test was found to vary with the heparin concentration and the donor of the platelets used in the test. The optimal heparin concentrations were between 0.1 and 1.0 U/ml. Using these heparin concentrations, the mean sensitivity varied from 39% (with the least reactive platelets) to 81% (with the most reactive platelets). In comparison, the sensitivity of the release test ranged from 65% to 94%. The specificities of the platelet aggregation test were 82%, 90% and 100% for the following control groups: (1) non-thrombocytopenic patients given heparin, (2) patients with thrombocytopenia due to other causes, and (3) normal controls not given heparin, respectively. The corresponding specificities for the release test was 94%, 90% and 100%. The specificities can be further increased to 100% for all controls with the adoption of a two-point system which defines a positive result as one in which platelet aggregation occurs with a low heparin concentration (0.5 U/ml) but not with 100 U heparin/ml. For optimal results, a two-point platelet aggregation test should be performed with heparin concentrations of 0.5 and 100 U/ml and using platelets of more reactive donors.

scholarly journals Automated image analysis method for oil-release test of lipid-based materials

MethodsX ◽  
2021 ◽  
pp. 101447
Author(s):  
Fabio Valoppi ◽  
Petri Lassila ◽  
Ari Salmi ◽  
Edward Haeggström
Keyword(s):  
Image Analysis ◽  
Automated Image Analysis ◽  
Analysis Method ◽  
Image Analysis Method ◽  
Release Test

Application of communication network theory to the electromagnetic seismograph

1964 ◽  
Vol 54 (5A) ◽  
pp. 1479-1489
Author(s):  
S. Dopp
Keyword(s):  
Communication Network ◽  
Transfer Function ◽  
Equivalent Circuit ◽  
Network Theory ◽  
Band Pass Filter ◽  
Pass Filter ◽  
Electromagnetic Seismograph ◽  
Band Pass

Abstract Communication network theory is applied to the equivalent circuit of the electromagnetic seismograph. The seismograph's transfer function is derived in the general case of an arbitrary linear passive coupling network between pendulum and galvanometer. Examples are given, one of which refers to the construction of a band-pass filter in the form of a lattice of filter galvanometers.

Magnification curves of electromagnetic seismographs

1964 ◽  
Vol 54 (5A) ◽  
pp. 1459-1471
Author(s):  
S. K. Chakrabarty ◽  
G. C. Choudhury ◽  
S. N. Roy Choudhury
Keyword(s):  
General Solution ◽  
Frequency Response ◽  
Experimental Method ◽  
Phase Shifts ◽  
Response Curves ◽  
Operating Condition ◽  
Coil Inductance ◽  
The World ◽  
Electromagnetic Seismograph ◽  
Proper Design

Abstract The general solution of the equations connecting the motion of the two coupled components in an electromagnetic seismograph has been obtained in another paper and it shows that the magnification of a seismograph depend on seven instrumental constants. Using these results, equations and curves have been derived in the present paper from which the Magnification as well as Phase shifts in the response of a seismograph and their variations with damping and coil inductance can be easily obtained. Based on these curves a number of magnification curves for different combinations, which are in operation at the different seismological stations of the world, have been derived. Suitable equations and curves have also been obtained which can be used for estimating the absolute Magnification of a Seismograph. An experimental method of obtaining the frequency response curves of seismographs in their operating condition has been described and the results obtained by this method has been given. It has been indicated how the results incorporated in the present paper can be used in the proper design of seismographs required for the different purposes.

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