Three-dimensional instrument polarization analysis and optimization of liquid-crystal-based Stokes polarimeter.

The Stokes polarimeter based on liquid crystal variable retarders (LCVRs) is a space polarization measurement technology widely used. However, due to the tilt of the optic axis of the LCVR with the driving voltage in the direction of light propagation and the interference in LCVR, the LCVRs-based Stokes polarimeter produces a large instrument polarization, which affects the accurate polarization measurement. In this paper, we combine polarization ray tracing with multi-beam interference, and establish a general three-dimensional polarization analysis model of the LCVRs-based Stokes polarimeter. The simulation results of adjusting the LCVR voltage to reduce the instrument polarization are analyzed, and the variation of polarization measurement accuracy with the field of view before and after optimization of the LCVRs-based Stokes polarimeter is simulated and analyzed. A LCVR structure with additional films for matching the refractive index is proposed. According to the simulation results, this structure can significantly reduce the interference effects and reduce the impact of variations in liquid crystal layer thickness on the interference effects.

Sperm DNA damage and unexplained recurrent spontaneous abortion / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the relationship of sperm DNA damage with unexplained recurrent spontaneous abortion (URSA).</p><p><b>METHODS</b>Sperm DNA fragmentation was evaluated by sperm chromatin dispersion (SCD), and the results were expressed in terms of DNA fragmentation index (DFI). DFIs were measured in the male partners of 56 women with URSA (the experiment group) and of 31 without URSA (the control group).</p><p><b>RESULTS</b>The DFI was shown to be (11.0% - 56.9%) in the experiment group, 21 (37.5%) of the subjects over 30%, as compared with (10.0% -36.8%) in the control group, only 8 (25.8%) of the subjects over 30%, significantly higher in the former than in the latter (29.4% vs 25.5%, P < 0.05).</p><p><b>CONCLUSION</b>There is a relationship between sperm DNA damage and URSA.</p>

Effect of adenosine on electrophysiological changes of ventricular myocardium in rats with experimental diabetes / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the electrophysiological changes of ventricular myocardium of rats with experimental diabetes and the effect of adenosine on its electrophysiology.</p><p><b>METHODS</b>Diabetes was induced in male SD rats, using a single injection of alloxan into tail vein. Untreated animals were used as controls. The electrocardiograms (ECG) were recorded 6 weeks after diabetes was induced. Effects of adenosine on ventricular myocardium in diabetic rats and controls were observed by measuring the transmembrane potentials with conventional glass microelectrodes.</p><p><b>RESULTS</b>QT interval in ECG and action potential duration (APD) at all levels (APD30, APD50, APD70 and APD90) were significantly prolonged in right ventricular papillary muscle 6 week after diabetes was induced. No differences were observed in the resting membrane potential (RP), action potential amplitude (APA) and overshoot (OS) as well as the maximum rate of depolarization (Vmax) between the diabetic rats and control rats. At concentration of 10 approximately 400 micromol/L, ADO had little influence on all transmembrane potential parameters of right ventricular papillary muscle in diabetic rats and controls. At 500 micromol/L, ADO shortened APD30, APD50, APD70 and APD90 of control group, while having no effect on diabetic rats.</p><p><b>CONCLUSION</b>QT interval in ECG and APD at all levels are significantly prolonged in right ventricular papillary muscle of experimentally induced-diabetic rats.</p>