Short time delays change pattern induced flicker colors (PIFCs)

Subjects decided on whether the colors of the rings on a modified Benham's top were the same or different. The cause of color differences was a variable time delay. Δt, of the black and white stimulus pattern on the disc. Time delays of Δt = 50 μsec and less caused detectable changes in color and brightness.     

How to Tailor Structural Colors for Extended Visibility and White Light Generation Employing Direct Laser Interference Patterning

The appearance of a surface can be controlled by creating periodic microstructures designed to diffract light and produce structural colors. Nevertheless, since structural coloration is based on diffraction, the produced colors have a strong dependence on the viewing angle and absence of coloration takes place while tilting the samples. In this work direct laser interference patterning is used to firstly provide transparent polymer sheets a structural coloration with a high‐range observation angle, and secondly to demonstrate the combination of structural colors, producing a white coloring effect. The employed approaches are based on the fabrication of micro‐gratings with multiple periods in the same structured area and on the engineering of the diffraction orders of the diffraction spectrum. The patterned surfaces are characterized by confocal microscopy and angular spectrometry in reflection mode. The morphological characterization shows homogeneous surface patterns, while the spectral results demonstrate that combining four spatial periods on a single patterned surface, a white appearance is obtained over an angular observation range higher than 30°. The experimental results are supported by theoretical predictions by means of generalized formulas based on the diffraction of light.     

不同色彩背景对选择反应和运算能力的影响研究

目的: 对不同色彩背景下认知操作的任务完成绩效进行比较研究. 方法: 95名青年男性,完成不同色彩背景下的连续相加和字母选择认知测验. 结果: 认知任务均受到了色彩背景的影响,并且不同的色彩背景之间统计学上存在差异. ①在操作时限为2 min的简单选择任务中,彩色背景下测试成绩之间无统计学差异,而非彩色之间以及非彩色与彩色背景之间有统计学差异(F=2.257,P＜0.05);②在连续相加任务中,操作时限为9 min,非彩色与彩色背景之间均有统计学差异(F=2.115, P＜0.05). 结论: 在视屏操作过程中,不同的背景色会影响到操作功能的反应速度和准确性,并且与任务难度及操作时间有关.     

偏最小二乘法-分光光度法同时测定多种食用合成色素

目的:探讨偏最小二乘法(PLS)分光光度法同时测定多种食用合成色素中的应用.方法:柠檬黄、日落黄、胭脂红、苋菜红的λmax分别是428±2nm、482±2nm、508±2nm、520±2nm,表明它们的吸收光谱严重重叠,用PLS法辅助分光光度法,不经分离,同时测定上述四组分混合体系中各组分的含量.结果:四组分混合体系中各组分的平均回收率和RSD分别为100.6%、100.5%、99.5%、101.1%和1.28%、1.11%、1.01%、1.96%.实测两种样品,均获得较好结果.结论:PLS法为不经分离直接测定的多组分体系分光光度分析提供了一种新的途径.     

Effect of an experimental desensitizing agent on reduction of bleaching-induced tooth sensitivity: A triple-blind randomized clinical trial

Background

In this randomized study, split-mouth, triple-blind clinical trial, the authors evaluated the efficacy of a desensitizing gel that contained 5% potassium nitrate and 5% glutaraldehyde applied before in-office bleaching with 35% hydrogen peroxide (HP).

Synthetic food colors and neurobehavioral hazards: the view from environmental health research

Background: The proposition that synthetic food colors can induce adverse behavioral effects in children was first enunciated in 1975 by Feingold [Why Your Child Is Hyperactive. New York:Random House (1975)], who asserted that elevated sensitivity to food additives underlies the signs of hyperactivity observed in some children. Although the evidence suggested that some unknown proportion of children did respond to synthetic food colors, the U.S. Food and Drug Administration (FDA) interpreted the evidence as inconclusive. A study published in 2007 [McCann et al. Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. Lancet 370:1560–1567 (2007)] drew renewed attention to the hypothesis because of the study’s size and scope. It led the FDA to review the evidence, hold a public hearing, and seek the advice of its Food Advisory Committee. In preparation for the hearing, the FDA reviewed the available evidence and concluded that it did not warrant further agency action.Objectives: In this commentary I examine the basis of the FDA’s position, the elements of the review that led to its decision and that of the Food Advisory Committee, and the reasons that this is an environmental health issue.Discussion: The FDA review confined itself, in essence, to the clinical diagnosis of hyperactivity, as did the charge to the committee, rather than asking the broader environmental question of behavioral effects in the general population; it failed to recognize the significance of vulnerable subpopulations; and it misinterpreted the meaning of effect size as a criterion of risk. The FDA’s response would have benefited from adopting the viewpoints and perspectives common to environmental health research. At the same time, the food color debate offers a lesson to environmental health researchers; namely, too narrow a focus on a single outcome or criterion can be misleading.     

Methodology and Application for Health Risk Classification of Chemicals in Foods Based on Risk Matrix

The method has been developed to accurately identify the magnitude of health risks and provide scientific evidence for implementation of risk management in food safety.It combines two parameters including consequence and likelihood of adverse effects based on risk matrix.Score definitions and classification for the consequence and the likelihood of adverse effects are proposed.The risk score identifies the intersection of consequence and likelihood in risk matrix represents its health risk level with different colors:‘low',‘medium',‘high'.Its use in an actual case is shown.     

空间及颜色对交通灯判断速度影响的研究

目的 研究交通灯空间因素和颜色意义对信息加工处理速度的影响.方法 20名健康成年男性(年龄:18～30岁),模拟交通灯作为图片刺激.分别在正常条件、位置相反、颜色意义相反、位置及颜色意义均相反四种条件下各进行一次Go/NoGo任务测试,实验顺序随机,电脑自动记录正确率和反应时.结果 ①受试者四种条件的平均正确率高达99.13%,各组内及组间均无明显差异.②正常条件下受试者对红绿灯的反应时分别为[红灯(491.59±71.74)ms;绿灯(487.55±58.11)ms],差异无显著性(P=0.522).③位置相反条件为[红灯(606.29.±107.59)ms;绿灯(593.13±102.45)ms]、颜色意义相反条件为[红灯(572.08 ±78.75)ms;绿灯(592.43±87.58)ms].与正常条件相比,位置相反条件红绿灯反应时均延长(F(1,19)=59.77,P<0.01);颜色意义相反条件红绿灯反应时均延长(F(1,19)=52.55,P<0.01).④位置及颜色意义均相反条件为[红灯(502.92±65.27)ms;绿灯(508.97±63.40)ms],与正常条件相比,反应时差异接近显著性(P=0.065).结论 违背常态的交通灯位置及颜色意义等冲突信息能延迟大脑信息加工处理速度,提示长时记忆中存在一种"概念的恒常性".     

数字舌图的色彩校正方法研究

在舌诊客观化的研究中，舌色的真实还原是一个关键的技术环节。本文运用ICC色彩特性文件对数字图像进行了色彩校正，实验结果表明，此方法能够有效的校正数字图像的色偏，是一种行之有效的色彩还原方法。