Evaluation Of Multiple Parameters Research Articles

Improvement of Tryptophan Analysis by Liquid Chromatography-Single Quadrupole Mass Spectrometry Through the Evaluation of Multiple Parameters.

Tryptophan is a key component in many biological processes and an essential amino acid in food and feed materials. Analysis of the tryptophan content in proteins or protein-containing matrices has always been a challenge. We show here that the preparation of samples prior to tryptophan analysis can be significantly simplified, and the time consumption reduced, by using ascorbic acid as antioxidant to eliminate the problem of tryptophan degradation during alkaline hydrolysis. Combined with separation by HPLC and detection by Single Quadrupole Mass Spectrometry, this allows the analytical run time to be reduced to 10 min. The alkaline hydrolysate obtained in the method presented here may be combined with the oxidized hydrolysate obtained when sulfur-containing amino acids are to be measured, thus essentially providing two analyses for the time of one.

Research and Application on Fault Diagnosis for Steam Turbine Using Multi-Parameter Fusion

For the running situation of supercritical and ultra-supercritical steam turbine unit, a fault diagnosis method of steam turbine based on multiple parameters fusion is proposed. The association of the fault mode with the vibration parameters, the thermodynamic parameters and the operational parameters is built, according to fault development mechanism, equipment operation data and professional experience. The overall state evaluation of mechanical equipment is given, the reliability of fault diagnosis is improved, and the need of the steam turbine fault diagnosis is met, by means of comprehensive evaluation of multiple parameters. Example applications verify this method.

ThermoCool® SmartTouch® Catheter – The Evidence So Far for Contact Force Technology and the Role of VisiTag™ Module

Catheter ablation has become an important modality in the treatment of most cardiac arrhythmias. In recent years there has been significant development of new ablation energies and technologies in an attempt to improve clinical outcomes and decrease disease burden. Ablation failure is often associated with inadequate lesion formation, and catheter-to-myocardial contact force (CF) and catheter stability are two of the parameters required to produce effective lesions during radiofrequency energy application. Recently, CF sensing catheters and tagging modules have been developed to give operators realtime data on catheter force and stability. This review describes the novel ThermoCool® SmartTouch® Catheter (Biosense Webster Inc., CA, US) and VisiTag™ Module (Biosense Webster Inc., CA, US) software, and discusses the results of several studies on CF and catheter stability during mapping and ablation of the left atrium and ventricle from our electrophysiology laboratory. We assess the short- and longer-term outcomes during mapping and ablation with and without CF data, as well as the use of the VisiTag Module™ software, which allows the evaluation of multiple parameters of lesion formation, then integrates and displays this as automatic tags in a relatively objective way.

A part le fibrinogène, les facteurs/marqueurs d’hémostase ont-ils aussi une place pour évaluer le risque d’accident cardiovasculaire ischémique ?

Most cardiovascular events result from a thrombotic complication of atherosclerotic lesions. In arterial vessels such as the coronary bed, an interrelationship of haemostatic, coagulation and fibrinolytic factors is implicated. While it can be demonstrated that fibrinogen is a risk factor/marker, the role of other factors is not well established. Under arterial flow conditions, platelets are predominantly involved in the thrombotic reaction. Yet, apart from a large increase in the platelet count, the involvement of platelet parameters in cardiovascular risk is not clearly evident. The lack of definitive platelet markers is at least partly due to the difficulty of studying platelet function ex vivo. Several polymorphisms of platelet glycoproteins carrying a moderate increase in risk have been reported, but only in younger patients. One potentially important factor for coagulation is the fibrin structure, which is dependent on fibrinogen, the rate of thrombin generation, the activity of factor XIII and the interrelationship of the cells concerned, all of which act on its sensitivity to thrombosis. Coagulation factors largely affect the rate of thrombin generation. The activity of the fibrinolytic system (and principally any deficiency) has a role in the cardiovascular risk. General markers of cardiovascular risk such as D-dimers are potentially useful, but they increase with thrombin generation and are decreased by a deficiency in fibrinolysis. Furthermore, possibly because they are not indicative of the fibrin structure, they are poorly correlated with clinical events. The poor significance of the available haemostatic, coagulation and/or fibrinolytic parameters is probably due to their lack of representativeness, since haemostatic, coagulation and fibrinolytic systems are all involved in the thrombotic response (and some in atherogenesis itself). Atherogenesis is a multifactorial process and numerous moderate risk factors act in association. Better predictability of the haemostatic tests would probably result from both the design of more representative tests and the evaluation of multiple parameters, and would lead to the definition of a risk score. Technological advances will make this possible.