The observed bias was shown to be caused by particle bounce following the displacement of Alvocidib in vitro surfactant by the shear force of the airflow diverging above the collection plate of the second impaction stage. A procedure was subsequently developed that eliminated this source of error, as described in the second article of this series (submitted to AAPS PharmSciTech). Measurements obtained with both abbreviated impactors were very similar in precision to the ACI for all measures of in vitro performance evaluated. Such abbreviated impactors can therefore be substituted for the ACI in certain situations,
such as inhaler QC or add-on device testing.”
“The fatigue failure mechanism of rubber bearings under cyclic compression is important in evaluating their fatigue lives and thus is analyzed theoretically and numerically here. At first, the stress distributions in a bonded rubber PF-6463922 mw cylinder derived from three different existing models were utilized to calculate the cracking energy densities within it. Next, the location of
fatigue crack initiation and the direction of subsequent crack propagation in circular rubber bearings were consecutively determined. Furthermore, finite element numerical results were compared to those obtained theoretically from the three models to check their validity in predicting the fatigue crack initiation and propagation in circular rubber bearings. Based on the quasi-statically theoretical and numerical results, it is found that the
fatigue cracks initiate first at the outermost boundary between rubber and steel plates and propagate later inwards to the center of circular rubber bearings. The corresponding fatigue failure mechanism obtained theoretically and numerically is consistent Selleck BTK inhibitor with experimental findings reported previously. (c) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 1747-1756, 2011″
“There are controversial data regarding the impact of coagulation factor XIII A subunit (FXIII-A) Val34Leu polymorphism in the pathogeneric of coronary artery disease (CAD) and myocardial infarction (MI). Assuming this genetic factor is associated with the thrombotic process, we explored the role of FXIII-A Val34Leu in CAD and MI in a Chinese Han population. We recruited 195 consecutive patients with CAD confirmed by coronary angiography as well as a group of 203 controls. Factor XIII A Val34Leu polymorphism was determined through polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis. We did not find the Leu/Leu genotype in patients with CAD or controls. No significant difference in Val34Leu gene polymorphism distribution was found between patients with CAD and the controls (P = .923). Subgroup analysis according to the history of MI showed the heterozygote Val/Leu genotype was associated with a significantly decreased risk of MI (P = .005; adjusted odds ratio [OR] = 1.75; 95% confidence interval [CI] = 1.28-2.25).