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As a technique to improve the ability of optical films to resist laser-induced damage (ARLID), laser preconditioning has been investigated broadly. In this paper, the laser preconditioning effect has been analyzed based on the defect-initialized damage mechanism that the author had put forward previously. Theoretical results show that an energy density scope (PEDS) exists in which the preconditioning laser can effectively improve the ARLID of optical films. In addition, when the energy density of the testing laser pulse is altered, the boundary of PEDS will change accordingly. Experimental results have verified these theoretical assumptions. PEDS will also become wider if the critical energy density of the preconditioning laser that can induce films' micro-damage increases, or the critical energy density of the preconditioning laser that can cause laser annealing decreases. In these cases, it is relatively easy to improve the ARLID of optical films. Results of the current work show great significance in enhancing the ARLID of optical films through the laser preconditioning technique. (C) 2008 Elsevier B.V. All rights reserved.

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中国科学院基金;国家自然科学基金

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研究采用PCR-SSCP技术研究番鸭不同就巢群体(就巢1月群、就巢2月群、就巢3月群)、番鸭非就巢群和白改鸭5个群体250个个体PRL基因第4外显子多态性与就巢性状之间的相关性.结果表明,在外显子4编码区内发现2个SNP位点,分别位于该基因的3 777 bp(T/C)和3 785 bp(MG)处.基因型与就巢性状指标相关分析的结果表明,番鸭非就巢群体与各就巢群体间差异极显著(P<0.01),同时番鸭与白改鸭差异显著(P<0.05),推测PRL基因与就巢性有一定的相关.

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光照能明显改变正常人和动物瞳孔的大小,而精神疾病及药物滥用则影响人和动物瞳孔对光的反应性。因此,瞳孔对光反应异常可以用作检测精神疾病和药物滥用的指标。有关药物滥用是如何影响瞳孔对光的反应性的研究还很少。为定量地测量成瘾性药物对瞳孔光反应变化的影响,该文采用猕猴为实验对象,通过在黑暗环境中测量猕猴在吗啡给予前和吗啡给予后的不同时间段,其瞳孔直径大小以及其对光反应能力的变化情况,来系统研究吗啡是如何影响这种非自主性反射系统的。研究发现,吗啡给予降低了猕猴在黑暗环境中的扩瞳反应,并且降低了瞳孔对光反应的收缩率。该文为将瞳孔对光反应特征用作鉴定吸毒者的检测手段提供了实验依据。