Contributions to the chemistry of human hair: III. Protein chemical aspects of permanent waving treatments

The influence of permanent waving on hair proteins was studied in order to obtain additional information about the chemistry of this cosmetic treatment. It was shown by amino acid analysis that with increasing reduction time during treatment fewer disulphide bonds were reformed in hair during subsequent reoxidation. Simultaneously, an increasing amount of sulphur-containing material is liberated from the hair, as demonstrated by the sulphur balance calculated from the sulphur-containing amino acids. The amount liberated is increased when an extensive soaking of the samples in water between the reduction and reoxidation step is performed. Comparing treatments with the use of reducing solutions of pH values between 7.5 and 10.0, it was found that the largest amount of cystine cleavage occurs at pH 9.0. All hair samples reduced at pH values above pH 8.5 showed incomplete reformation of the disulphide bonds during subsequent reoxidation. This was indicated by the content of free SH-groups and cysteic acid, as quantified by amino acid analysis. The damage to the hair proteins due to permanent waving was further confirmed by the determination of the pronase solubility. The reductive treatment of hair at pH 7.5 led to a relatively low degree of reduction, however all sulphur bonds were reformed during subsequent reoxidation.     

Textile solar light collectors based on models for polar bear hair

Concepts of technical fibers following models for the polar bear hair to be used for textile solar collectors are discussed. The approach to coat fibers with a thin layer into which fluorescent dyestuff was dispersed was studied experimentally. Modified fibers made of different polymers were characterized with respect to optical properties relevant for the bionic model. In the case of poly(methylmethacrylate) fibers, the envisaged effect could be achieved to high efficiency. The optical performance could be enhanced by ultrasonic dispersion of the dyestuff in the coating matrix. The effect is less significant in semi-crystalline fibers such as poly(ethylene terephthalate), which is attributed to diffuse scattering.     

The role of primary alkanolamines in cosmetic formulation

Alkaline products are commonly used in cosmetic preparations as neutralizing agents for acid-functional raw materials. Primary alkanolamines can provide positive attributes in such cases. The properties of nitroparaffin-derived primary alkanolamines are compared here with the general requirements for cosmetic-type acid-neutralizing materials.
Acid-functional copolymers, used as hair fixatives in both aerosol and non-aerosol products, are efficiently solubilized by neutralization with 2-amino-2-methyl-1-propanol (amino-methylpropanol) in a variety of aqueous and non-aqueous systems. The effects of such neutralization on resultant film properties which influence product performance are discussed in detail.
Upon neutralization, crosslinked acrylic-acid polymers of varying molecular weights (carbomers) provide significant benefits when used as thickeners, gellants or emulsifiers in cosmetic products. New data are added to previous knowledge on the use of tris(hydroxymethyl)aminomethane (tromethamine) as a neutralizing agent for three resins, especially in gelled formulations. Alcohol compatibility, pH behaviour, and viscosity characteristics of such formulations are described. In addition, toxicological considerations of primary alkanolamines are addressed.
Further to the above applications, nitroparaffin-derived primary alkanolamines can be effectively used as cosmetic emulsifiers (in the form of their fatty-acid soaps), dispersants or co-dispersants for particulate-containing products, and pH buffers/stabilizers.     

基于指标适度标准化的界面风格美综合评价模型

为了客观、定量地评价界面布局的美度,从设计风格的角度,提出非线性审美综合评价模型. 以“活泼美”为例,基于已提出的美度指标体系,针对各美度指标的形式特征设计各组实验样本,计算各样本美度指标值,运用李克特量表法对“活泼美”进行调查评分;运用最小二乘法将各美度指标值与“活泼美”调查值进行曲线拟合,得出关系表达式,实现美度指标适度标准化;运用逼近理想解排序法和相关性定权法,建立界面布局“活泼美”的综合评价模型. 对10个界面样本进行实例研究,运用心理物理学中的两极递进式排序法对模型进行验证分析。结果表明,模型具有良好的精度,可以作为界面智能设计系统的适应度评价函数,为界面智能设计的发展提供可靠的技术支撑.     

Alteration of Skin Properties with Autologous Dermal Fibroblasts

Dermal fibroblasts are mesenchymal cells found between the skin epidermis and subcutaneous tissue. They are primarily responsible for synthesizing collagen and glycosaminoglycans; components of extracellular matrix supporting the structural integrity of the skin. Dermal fibroblasts play a pivotal role in cutaneous wound healing and skin repair. Preclinical studies suggest wider applications of dermal fibroblasts ranging from skin based indications to non-skin tissue regeneration in tendon repair. One clinical application for autologous dermal fibroblasts has been approved by the Food and Drug Administration (FDA) while others are in preclinical development or various stages of regulatory approval. In this context, we outline the role of fibroblasts in wound healing and discuss recent advances and the current development pipeline for cellular therapies using autologous dermal fibroblasts. The microanatomic and phenotypic differences of fibroblasts occupying particular locations within the skin are reviewed, emphasizing the therapeutic relevance of attributes exhibited by subpopulations of fibroblasts. Special focus is provided to fibroblast characteristics that define regional differences in skin, including the thick and hairless skin of the palms and soles as compared to hair-bearing skin. This regional specificity and functional identity of fibroblasts provides another platform for developing regional skin applications such as the induction of hair follicles in bald scalp or alteration of the phenotype of stump skin in amputees to better support their prosthetic devices.     

室内装潢中的木制品之美

以木制品为研究主体,分析了木制品在室内装潢中具有的自然美、结构美及技术美,指出木材给人以文静、柔和、素雅的感受,将点、线、面结合为不同的结构形式,体现了装潢设计的艺术与智慧,在室内装潢中产生了很高的价值。     

激光直写法制备仿刚毛微纳阵列的研究

提出一种采用激光直写技术制备微纳阵列的新方法来制备仿壁虎刚毛二级结构微阵列。该制备过程由计算机控制完成。实验制备出具有不同几何尺寸的一级结构阵列,并在此基础上探索制备二级结构微阵列的三种方案,其中,“自上而下”的方案通过对曝光时间和显影时间的控制使第二级结构扎根于第一级结构中,有效提高了两级结构间的连接强度。制备实验的同时,分析了曝光时间、显影时间等参数对阵列制备的影响。激光直写制备微纳阵列的方法具有高效率、低成本的优点。     

头发角蛋白质子导电材料的制备和理化特性表征

将头发氧化后用模压法制备了氧化角蛋白膜,考察了氧化角蛋白膜的电导率及其影响因素,并对其进行了表征。考察了角蛋白膜的微观结构、氧化前后头发角蛋白的官能团变化以及氧化时间、模压压强、颗粒粒径对电导率的影响。实验结果表明,角蛋白膜的电导率达3.6×10-3S/cm,且随氧化时间延长,电导率先上升后下降,随模压压强的增大,电导...     

分形图形在包装设计中的应用研究

从构图独特、神奇美丽又变幻莫测的分形图形出发,首先介绍了分形的概念,然后分析了分形图形对称与均衡、节奏与韵律等的艺术美特征。在此基础上,从包装的促销功能出发,研究了分形图形用于包装设计的可行性。最后通过几款包装设计作品,用实例展示了分形图形用于包装的独特性和促销性。