Metals in female scalp hair globally and its impact on perceived hair health

Globally, billions of individuals wash their hair in water, which acts as an exogenous metal source. Many studies which measure the metal levels found on human hair specifically aim to remove exogenous materials prior to analysis. Although this is needed when using hair analysis to probe the impact of the local environment on endogenous metal levels, it is not relevant for understanding exactly what is on hair as a result of contact with its daily environment. Understanding these levels are important, as the presence of redox active metals, such as copper and iron, can impact fibre health, either as a result of UV irradiation, or during the hair colouring process. A global hair sampling study of over 300 individuals from nine countries has been performed, and the combined endogenous and exogenous metals analysed. The levels measured vary widely, even within the narrow geography of each hair sampling location. The levels of calcium, magnesium, copper and iron were not correlated, and within each location, there are expected to be individuals with high metal levels. Levels increased from hair root to tip for calcium, magnesium and copper, attributed to hair contact with the environment showing the impact of exogenous metals in the overall levels on hair. Levels of redox metals were comparable between individuals who coloured or did not colour their hair, although water hardness ions were statistically significantly higher for hair colouring individuals. Individuals who perceived their hair health as poor had higher metal levels on their hair. Controlling metals on hair, either by preventing their binding during environmental contact, or through controlling their ability to cause hair damage, should lead to improved consumer perceived hair health.     

Equilibrium moisture content and sorption isosteric heats of five wheat varieties in China

The moisture sorption isotherm data of five Chinese wheat varieties were investigated via the gravimetric static method at five different temperatures (10, 20, 25, 30, and 35 °C) and relative humidity ranging from 11.3 to 96.0%. The sorption data of wheat decreased with an increase in temperature at a constant relative humidity (r.h.). The hysteresis effect was observed between adsorption and desorption isotherms. The width and span of the hysteresis loop decreased with increased temperature, but was not influenced by the hardness of wheat varieties. Six models, namely the Chen-Clayton (CCE), Modified BET (BET), Modified-Chung-Pfost (MCPE), Modified-Henderson (MHE), Modified-Oswin (MOE) and Strohman-Yoerger (SYE), were employed to describe the experimental data. The BET, MCPE and MOE models were selected to best describe the sorption isotherms of wheat in the ranges of 11.3-49.9, 11.3-96.0 and 11.3-96.0% r.h., respectively. The hygroscopic property difference between hard wheat (cv. ‘Longyuan’ and ‘Nanduan’) and soft wheat (cv. ‘Zhaozhuang’ and ‘Lumai’) was very small. The sorption isosteric heat of wheat decreased with an increase in moisture content until the dry bulb moisture content (m.c.) of 20% was reached, and then decreased smoothly with increasing moisture content. A big difference was found between adsorption and desorption isosteric heats of wheat below 20% m.c., but the sorption isosteric heat difference between hard and soft wheat isotherms was small.     

多孔纤维织物热湿传递数值模拟的研究进展

热湿传递数值模拟的研究可为多孔纤维织物的制备和热湿性能评估提供理论基础。在阐述了织物热湿传递机制的基础上,从织物热湿传递数值模型、数值模拟计算方法以及织物热湿传递性能测试方法 3个方面,综述了近年来关于织物热湿传递方面的新进展,分析了现有织物传热传湿数值模拟研究中存在的问题,提出在创建织物三维方向上的热湿耦合模型时,要综合考虑织物本身的交织结构特征和纱线的物理性能;在数值分析过程中要充分考虑实际应用条件下织物材料物理性能的变化,进一步优化织物传热传湿数值模型,提高模拟计算的准确度。     

Evaluation of moisture management properties on knitted fabrics

In order to determine the effect of raw material, weave type and tightness on liquid absorption and transmission which is an important factor in the perception of people’s clothing comfort, knitted fabrics made of cotton, viscose and polyester yarns, which had single jersey, 1?×?1 rib and single pique weave type, had three different tightness as tight, medium and loose, were produced. Moisture management tester (MMT) was used for multi-dimensional liquid transport of the fabrics produced. As a result of the study, it is observed that polyester fabrics had higher OMMC values than those of cellulosic-based fabrics. Regarding the effect of tightness, liquid transport has decreased with increasing tightness in general. Weave types examined in this study, were not as strong as raw materials and tightness and did not have such a significant effect.     

Effects of a new mild shampoo for preventing hair loss in Asian by a simple hand-held phototrichogram technique

This study was conducted to evaluate the effects of a commercially available shampoo in Korean subjects with alopecia using a simple hand‐held phototrichogram technique. Forty‐four subjects with alopecia were enrolled and forty subjects continued for 16 weeks. In the test group, total hair counts increased significantly at weeks 8 and 16, and the number of shedding hair significantly decreased at week 16. Terminal hair counts significantly increased at week 8. In the control group, hair thickness and the number of vellus hairs significantly decreased at week 16. The number of total hairs significantly increased in the test group than in the control group at weeks 8 and 16. The number of shedding hairs significantly decreased in the test group than in the control group at week 16. Visual assessment using clinical digital images showed that the number of total hairs appeared to increase although there was no statistical significance. In this study, it was found that the test shampoo could prevent hair loss.     

仓储粮堆内热湿耦合传递的数值模拟

本文通过理论分析与数值模拟相结合的方法,以典型吸湿性多孔介质—小麦为研究对象,根据小麦吸湿和解吸湿曲线,建立了吸湿性多孔介质内部热湿耦合传递的数学模型,通过与相关实验数据比较验证了数学模型的合理性。基于有限元的方法模拟分析了外界气温和小麦分别为273K(0℃)和293K(20℃),小麦初始水分为14%和18%时直径为10m高度为10m的充满小麦的圆柱仓内部热湿迁移过程,重点探究了近似冬季和夏季仓储粮堆内部温度和水分的动态变化规律。研究结果表明,冬季工况下水分从粮堆内部向顶部和右侧壁面迁移,聚集在相对狭窄的壁面边界附近,形成低温高水分区域,最大水分值出现在右上部侧壁面附近。夏季工况下水分从顶部和侧面向内迁移,而内部又朝右上部区域扩散,形成较宽的高温高水分区域(r <4.5m, 8.0m 相似文献   

Changes in glutathione content in human hair follicle keratinocytes as a function of age of donor: relation with glutathione dependent enzymes

Glutathione (GSH) plays an important role in cellular protection during ageing. The hair plucking technique is a non-invasive method for the direct biochemical study of keratinocytes. Hair was taken from the suboccipital area of 63 volunteers (men and women whose ages ranged from 13 to 103 years). The results show a diminution in the glutathione content as a function of age. We compare two groups of population: group A (less than 80) and group B (more than 80). A remarkable fact is observed: group B displays a weak dispersion of the values as compared to A. The glutathione content (nmol 10⁻³ mg DNA) is 5.42 ± 0.60 for A and 1.86 ± 0.35 for B. A reduction of 88% was observed in glutathione reductase activity and of 78% in the activity of glutathione-S-transferase from group A to group B. The glutathione peroxidase activity remains relatively constant. The decrease in the GSH concentration and the constancy of the glutathione peroxidase suggest that the capacity of the cell to protect itself from peroxides remains unchanged but that the GSH concentration may become the limiting factor.     

稻谷自然储藏多尺度热湿耦合传递研究

该文采用计算流体力学(Computational Fluid Dynamics,简称CFD)的方法,以稻谷为研究对象,建立粮堆内部和粮粒热湿传递的数学模型,从粮堆和粮粒两种尺度,探究自然储藏过程中外界气象参数变化时粮堆内部的热湿变化以及稻谷颗粒内部热湿传递与周围空气的温湿度关系。研究发现自然储藏时粮堆内温度变化和水分迁移主要受外界环境与粮堆内自然对流的影响,且自然对流也会影响到粮堆和粮粒内部的温度和水分变化。但是粮粒内部温度变化不同于粮堆内部的温度的变化,因此,粮情检测系统的传感器测得的温度无法真实反应粮粒内部的情况。该文研究结果可为储藏过程中粮堆局部发热和霉变的控制与防护提供理论依据。     

The role of wheat flour constituents, sugar, and fat in low moisture cereal based products: a review on sugar-snap cookies

Much research has been done to understand the contribution of different flour constituents to the cookie quality. Most authors agree on the role of starch in cookies, which, although it is the main flour constituent, has a relatively small influence on cookie quality. Flour proteins, which are quantitatively less important than starch, seem to have a more pronounced role in cookie baking. However, in literature, there is no consensus about their role and influence on the product quality. As for starch, there is much more agreement about the role of non-starch polysaccharides and flour lipids. Not only flour, but also other ingredients of the cookie (dough) formula, such as shortening (fat), sugar, and water are important for the quality of the end product. We here provide the different points of view in this area and speculate on the functionality and quality determining properties of flour constituents, sugar, fat, and water and their role and influence during the different stages of cookie baking and on the end quality of sugar-snap cookies.     

染发剂中对苯二胺等32种染料检测结果分析

目的了解染发剂中染料使用情况和染发剂类化妆品安全风险点,为监管提供技术支撑。方法根据《化妆品安全技术规范》(2015年版),采用高效液相色谱法和超高效液相色谱-串联质谱法对湖南地区14个市、州地区抽样的50批染发剂类化妆品进行检测,分析其中染料种类、含量及使用情况。结果 50批染发剂共检出对苯二胺、对氨基苯酚等14种染料成分,其中对苯二胺、间氨基苯酚、间苯二酚3种染料的使用频率最高,均超过了60%。有2批染料的苯基甲基吡唑啉酮超出规定限量,其余均未超标。19批染发剂产品批件标识成分与实际检出结果不一致,不合格率为38%。结论染发剂使用情况及批件标识有待规范,应加强对染发剂类产品的监管。     

Mathematical modeling and numerical simulation of heat and moisture transfer in a porous textile medium

The moisture accumulation within clothing is a serious problem for sportswear and clothing in cold climate. There are several experimental methods available to measure moisture build up in insulate materials. However, information on parameters such as temperature, relative humidity and vapor pressure can be obtained through simulation using a predictive mathematical model. The focus of this study is the development of a mathematical model to simulate heat and moisture transfer in a sample of fabric, coated to provide insulation, which is in contact with human skin on one side and with the external environment on the other. To numerically simulate the mathematical model, the finite volume method is used and a computational procedure for the solution of the model is designed. The simulation results are analyzed to verify whether they are consistent with the physical reality.     

基于Luikov理论的烟丝贮丝过程热湿特性研究

通过对烟草热湿传递机理的分析,基于Luikov理论,建立了烟丝贮丝过程热湿传递方程,并利用量纲分析和Laplace转换对方程求解,得到烟丝堆积床温度场和湿含量分布的解析解,其结论为深入研究贮丝过程热湿迁移规律提供了理论依据.     

MPR1 as a novel selection marker in Saccharomyces cerevisiae

L ‐Azetidine‐2‐carboxylic acid (AZC) is a toxic four‐membered ring analogue of L ‐proline that is transported into cells by proline transporters. AZC and L ‐proline in the cells are competitively incorporated into nascent proteins. When AZC is present in a minimum medium, misfolded proteins are synthesized in the cells, thereby inhibiting cell growth. The MPR1 gene has been isolated from the budding yeast Saccharomyces cerevisiae Σ1278b as a multicopy suppressor of AZC‐induced growth inhibition. MPR1 encodes a novel acetyltransferase that detoxifies AZC via N‐acetylation. Since MPR1 is absent in the laboratory strain of S. cerevisiae S288C, it could be a positive selection marker that confers AZC resistance in the S288C background strains. To examine the usefulness of MPR1, we constructed some plasmid vectors that harboured MPR1 under the control of various promoters and introduced them into the S288C‐derived strains. The expression of MPR1 conferred AZC resistance that was largely dependent on the expression level of MPR1. In an additional experiment, the galactose‐inducible MPR1 and ppr1⁺, the fission yeast Schizosaccharomyces pombe homologue of MPR1, were used for gene disruption by homologous recombination, and here AZC‐resistant colonies were also successfully selected. We concluded that our MPR1–AZC system provides a powerful tool for yeast transformation. Copyright © 2009 John Wiley & Sons, Ltd.     

织物结构改变对吸湿排汗性能的影响

从纤维类别、织物紧密度、织物组织等因素的改变来改善织物的吸湿透汽性。主要选用天然纤维中的棉和化纤中的二维中空涤纶、普通圆截面涤纶、纳米竹碳涤纶,采用纯纺或混纺方式,以不同紧度和平纹、2/2斜纹、透孔、六枚变则缎纹4种组织织成织物。采用正交试验和极差分析方法,对16种不同织物的吸水高度和透湿量进行检测,找出最主要影响因素。结果表明,织物的原料成分是影响吸湿排汗性的最主要因素,中空涤纶与棉混纺织物比普通涤棉混纺织物的吸水度高276.5%,透湿量高75%。     

Understanding the role of natural cheese calcium and phosphorous content,residual lactose and salt‐in‐moisture content on block‐type processed cheese functional properties: Cheese hardness and flowability/meltability

Four treatments of natural Cheddar cheese with two levels (high and low) of calcium (Ca) and phosphorus (P), and two levels (high and low) of residual lactose were manufactured. Each treatment was subsequently split prior to the salting step of cheese manufacturing processed and salted at two levels (high and low) for a total of eight treatments. The eight treatments included: high Ca and P, high lactose, high salt‐in‐moisture (S/M) content (HHH); high Ca and P, high lactose, low S/M (HHL); high Ca and P, low lactose, high S/M (HLH); high Ca and P, low lactose, low S/M (HLL); low Ca and P, high lactose, high S/M (LHH); low Ca and P, high lactose, low S/M (LHL); low Ca and P, low lactose, high S/M (LLH); and low Ca and P, low lactose, low S/M (LLL). After 2 months of ripening, each treatment of natural Cheddar cheese was used to manufacture processed cheese using a twin‐screw Blentech processed cheese cooker. All of the processed cheese food formulations were balanced for moisture, fat and salt. Texture and melt‐flow characteristics of the processed cheese were evaluated with different techniques, including texture profile analysis (TPA) for hardness and melt profile analysis. There was a considerable increase in cheese hardness for the processed cheeses prepared from high Ca and P content, and high S/M natural cheeses compared with low Ca and P content and low S/M natural cheeses. Moreover, definite decrease in flow rate and extent of flow was observed for processed cheeses manufactured from high Ca and P content, and high S/M natural cheeses than that of low Ca and P content and low S/M natural cheeses. No considerable trend was observed in hardness and melt‐flow characteristics for the processed cheeses manufactured from high and low residual lactose content natural Cheddar cheeses. This study strongly demonstrates that the characteristics of natural cheese (calcium and phosphorus content, lactose content and salt‐in‐moisture content) used in processed cheese manufacture have a significant impact on processed cheese functionality.     

食用木薯的加工现状及发展前景

为探究不同干燥方法对木薯酸淀粉性能的影响,本研究以木薯淀粉为原料,经乳酸菌发酵后,采用热风干燥、热泵干燥、真空冷冻干燥、喷雾干燥和太阳光晒干5种干燥方法制备木薯酸淀粉,对其性能进行测定分析,并采用变异系数法对性能进行综合评分。结果表明,热风干燥的木薯酸淀粉粒径跨度最大,为2.36,透明度、碘蓝值和持油性最小,分别为21.57%、8.96和1.74 g/g;热泵干燥的木薯酸淀粉比表面积最小,为351.83 m²/kg,堆积密度、析水率和凝沉性最高,分别为0.87 g/mL、33.02%和74.89%;真空冷冻干燥的木薯酸淀粉堆积密度、休止角和析水率最低,分别为0.73 g/mL、37.49°和4.64%,透明度、碘蓝值和持水性最高,分别为27.03%、19.64和1.43 g/g,溶解性最高;喷雾干燥的木薯酸淀粉比表面积、休止角和持油性最高,分别为407.43 m²/kg、54.11°和2.33 g/g,凝沉性最低,为67.00%;晒干的木薯酸淀粉跨度和持水性最低,分别为1.73和1.08 g/g。综合评分结果显示,真空冷冻、喷雾、晒干、热风和热泵干燥的木薯酸淀粉性能综合评分分别为0.60、0.38、0.18、−0.50和−0.64。综合分析,真空冷冻干燥制备的木薯酸淀粉性能最好,其次为喷雾干燥,晒干次之,热风和热泵干燥的最差。

     

梨果实后熟衰老过程中温度对活性氧清除的影响

本文以河北水晶梨为试材,研究了贮藏前期和在不同温度下贮藏的梨果实果肉的超氧自由基(O2)产生速率、超氧化物岐化酶(SOD)活性、过氧化氢(H2O2)含量和过氧化氢酶(CAT)活性的变化及温度对它们的影响。结果表明:贮藏前期SOD活性和CAT活性均要低于在20和5条件下贮藏七天的样品,而贮藏前期O2产生速率和H2O2含量则较大,并且在5条件下贮藏七天的样品其果肉SOD活性要高于在20条件下贮藏七天的样品,其果肉的CAT活性也要高于后者;相反地在5条件下贮藏七天的样品其O2产生速率则低于在20条件下贮藏七天的样品的O2产生速率,其H2O2含量也低于后者。