A comparison of vision-related quality of life between Defocus Incorporated Soft Contact (DISC) lenses and single-vision spectacles in Chinese children

ObjectiveThis study aimed to compare the vision-related quality of life (VRQoL) between Defocus Incorporated Soft Contact (DISC) lenses and single-vision spectacles in Chinese children, in order to evaluate their visual performance and subjective acceptance of this bifocal designed contact lenses treatment.MethodsChinese participants aged 7 to 12 years, with myopia of ?4.00 to ?0.75 D, astigmatism < 1.50 D, and monocular best-corrected visual acuity 0.0 or better, were recruited in the study. All participants had been wearing DISC lenses, or single-vision spectacles, for the last 6 to 18 months and were requested to complete the routine ocular examination and Chinese version of the Pediatric Refractive Error Profile (PREP 2) questionnaire. The questionnaire consisted of 7 scales: vision, symptoms, appearance, activities, handling, peer perception, and overall score. According to their habitual correction modalities, fifty-four children were allocated to the DISC group and 56 to the single-vision spectacles group. A generalized linear model was fitted to assess variables associated with the PREP 2 score.ResultsParticipants wearing DISC lenses scored significantly higher than those wearing single-vision spectacles for vision, appearance, activities, peer perception, and overall (all P < 0.05). The improvement of VRQoL in the DISC group was mainly represented in appearance, peer perception, and activities. The quality of life improved more for older participants on scales of vision, symptoms, handling, appearance, and overall score (all P < 0.05). The interaction between treatment and age was statistically significant for the activities scale (P < 0.05).ConclusionDISC lens wear significantly improves VRQoL in Chinese children compared with single-vision spectacles for most of the survey scales, especially in the areas of appearance, peer perception, and activities. The benefits provided by DISC lenses contribute to greater satisfaction than single-vision spectacles for myopic children.     

Numerical modelling of small disc creep test

Abstract

The small disc creep test is described. The disc creep curves observed need to be related to the creep properties of the material obtained by conventional testing. This relationship should include a means of assessing the creep damage which is initially present in the material and therefore to an estimate of remanent life. There are difficulties with such correlations and these are shown to be related to an imperfect understanding of the complex nature of the small punch test. This understanding can be improved by suitable physical modelling of the deformation occurring. The present paper describes a suitable finite element model and verifies the model against experimental observations of disc creep tests. The model uses a realistic creep deformation law which includes strain hardening, thermal softening and damage accumulation for 0·5Cr0·5Mo0·25V steel. It is shown that the results obtained from the test are sensitive not only to the initial condition of the specimen but also to the conditions of the test (e.g. the values of frictional forces at the punch/specimen interface). The paper makes suggestions of how the model may be used to optimise the disc creep test.     

Cigarette Smoke Extract Induces p38 MAPK-Initiated,Fas-Mediated Eryptosis

Eryptosis is a physiological mechanism for the clearance of senescent or damaged erythrocytes by phagocytes. Excessive eryptosis is stimulated under several pathologies and associated with endothelial injury and thrombosis. Cigarette smoke (CS) is an established risk factor for vascular diseases and cigarette smokers have high-levels of eryptotic erythrocytes. This study, for the first time, investigates the mechanism by which CS damages red blood cells (RBCs). CS extract (CSE) from commercial cigarettes was prepared and standardized for nicotine content. Cytofluorimetric analysis demonstrated that treatment of human RBCs with CSE caused dose-dependent, phosphatidylserine externalization and cell shrinkage, hallmarks of apoptotic death. CSE did not affect cellular levels of Ca²⁺, reactive oxygen species (ROS) or glutathione (GSH). Immununoprecipitation and immunoblotting revealed the assembly of the death-inducing signaling complex (DISC) and oligomerization of Fas receptor as well as cleaved caspase-8 and caspase-3 within 6 h from the treatment. At the same time-interval, CSE elicited neutral sphyngomielinase (nSMase) activity-dependent ceramide formation and phosphorylation of p38 MAPK. Through specific inhibitors’ nSMase, caspase-8 or p38 MAPK activities, we demonstrated that p38 MAPK activation is required for caspase-8-mediated eryptosis and that ceramide generation is initiator caspase-dependent. Finally, ex vivo analysis detected phosphorylated p38 MAPK (p-p38) and Fas-associated signaling complex in erythrocytes from cigarette smokers. In conclusion, our study demonstrates that CSE exposure induces in erythrocytes an extrinsic apoptotic pathway involving p38 MAPK-initiated DISC formation followed by activation of caspase-8/caspase-3 via ceramide formation.     

Design and implementation of automatic shading device for diffuse radiation measurement

Considering the problem of too large area the shading disc covered,complex shadow band coefficients and too big diffuse radiation measurement bias,an automatic shading device for diffuse radiometer is designed and realized. Set a shading ball on the automatic sun tracker,drive linkage parallelogram structure with the declination axis arm,the shading ball can rotate synchronously with the motion of the sun and shade beam radiation measured with pyranometer,thus shading beam radiation and measuring diffuse radiation can be realized automatically. The comparison test results show that the automatic shading device can realize diffuse radiation measurement automatically,the accuracy of diffuse radiation readings can get a 18. 7% improvement compared with traditional measure system,greatly improves the reliability and accuracy of the diffuse radiation measurement.     

冷轧压下量及时效温度对内生 复合钢板弱界面结合强度的影响

通过力学性能测试、扫描电镜及透射电镜观察，研究了冷轧压下量及时效温度对内生复合钢板弱界面结合强度的影响。结果表明随着冷轧压下量的增加，弱界面的结合强度明显降低；而随着时效温度的上升，弱界面的结合强度呈现上升的趋势。     

一种内生复合板弱界面结合强度的测试方法

提出了一种利用拉伸法和剪切法测定内生复合板钢板弱界面拉伸强度及剪切强度的测试方法.该方法具有测试简单、数据准确的特点.     

如何保证DISC静电涂装效果

讨论了涂料黏度、空气压力、涂料导电性、工件接地、静电高压及DISC加工精度对DISC静电涂装的影响,并提出了保证涂装效果的控制条件。     

Structural features of caspase-activating complexes

Apoptosis, also called programmed cell death, is an orderly cellular suicide program that is critical for the development, immune regulation and homeostasis of a multi-cellular organism. Failure to control this process can lead to serious human diseases, including many types of cancer, neurodegenerative diseases, and autoimmununity. The process of apoptosis is mediated by the sequential activation of caspases, which are cysteine proteases. Initiator caspases, such as caspase-2, -8, -9, and -10, are activated by formation of caspase-activating complexes, which function as a platform to recruit caspases, providing proximity for self-activation. Well-known initiator caspase-activating complexes include (1) DISC (Death Inducing Signaling Complex), which activates caspases-8 and 10; (2) Apoptosome, which activates caspase-9; and (3) PIDDosome, which activates caspase-2. Because of the fundamental biological importance of capases, many structural and biochemical studies to understand the molecular basis of assembly mechanism of caspase-activating complexes have been performed. In this review, we summarize previous studies that have examined the structural and biochemical features of caspase-activating complexes. By analyzing the structural basis for the assembly mechanism of the caspase-activating complex, we hope to provide a comprehensive understanding of caspase activation by these important oligomeric complexes.     

内生复合钢板中弱界面的测定

采用ＴＥＭ、ＳＥＭ及Ｘ－ｒａｙ研究了内生复合钢板的显微结构并对其弱界面进行了表征。结果表明：内生复合钢反的显微结构是由于低碳马氏体板条沿轧面和轧向近于平行排列构成的,其复合结构为（１００）织构取向带嵌于（１１１）织构基体中形成的层状结构,弱界面为（１００）／（１００）板条晶间界面。     

基于MATLAB/SIMULINK的柴油转子发动机性能模拟研究

在理论分析的基础上选择了数学模型,基于MATLAB/SLMULINK建立了仿真模型.并利用DZ270双缸柴油转子发动机的实验数据进行校准,通过仿真计算比较,三种工况下缸内压力的预测值和试验值的平均误差均在2%以内,满足工程应用要求;本模型易用于其它机型的仿真.