Selected mechanical paremeters of women‘s hair in the Caucasian population

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F46747885%3A24510%2F17%3A00010320" target="_blank" >RIV/46747885:24510/17:00010320 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11510/17:10365399

Výsledek na webu

<a href="https://pubmed.ncbi.nlm.nih.gov/28759188/" target="_blank" >https://pubmed.ncbi.nlm.nih.gov/28759188/</a>

DOI - Digital Object Identifier

—

Jazyk výsledku

angličtina

Název v původním jazyce

Selected mechanical paremeters of women‘s hair in the Caucasian population

Popis výsledku v původním jazyce

OBJECTIVE: More parameters have been used for more detailed description ofmechanical properties of human hair as a fibre than in analogous studies. All mea-sured samples were taken from five different locations on the heads of 60 womenof varied age. METHODS: For each hair, the diameter was determined optically andthen the test in the Deform Type 2 testing machine was carried out. Deformationcurves were obtained by testing 10 mm long samples up to the rupture point atconstant temperature, humidity and constant crossbar speed of 2 mm/min. Thecurves were processed with software for the calculation of mechanical parametersof the hairs. This specialized software has been designed by us for that purpose.Resulting values were arranged into tables and figures. RESULTS: As far as haircross-section is concerned, it has been found that for the European populationit appears to be rather higher – 86 μm – than indicated in formerly publishedtexts. The 56 μm mentioned in the work of other authors has been observed onlyutterly exceptionally, in 0.3 % of the population. All quantities studied (exceptextensibility) display moderate to strong positive skewness in comparison toGauss distribution. The most marked skewness is seen in the resilience. At thesame time, this quantity displays the highest value of non-Gaussian distribution.The elasticity module of 2.3±0.6 GPa is three times lower than the one reportedby other authors, yet according to the fact published in our work – which showsunambiguously that the thinner the hair, the higher elasticity module it displays– the value of 7.2 GPa for the 56 μm thick hairs is comparable and it confirms thehypothesis that the cortex, which is responsible for the mechanical strength of thehair, is contained in a higher ratio in thinner hairs. This similarly applies to theultimate strength; the linearity limit is hard to compare with literature, as it almostdoes not appear there. CONCLUSION: By measuring 886 samples from the headsof 60 adult women of European type, it was possible to ascertain the current normfor a larger number of mechanical parameters of the hairs. Further merit of thiswork is the fact that the hairs were taken systematically from five well-definedplaces of the studied heads in equal count, which is an aspect formerly publishedworks do not respect and they do not present the location of sampling.

Název v anglickém jazyce

Selected mechanical paremeters of women‘s hair in the Caucasian population

Popis výsledku anglicky

OBJECTIVE: More parameters have been used for more detailed description ofmechanical properties of human hair as a fibre than in analogous studies. All mea-sured samples were taken from five different locations on the heads of 60 womenof varied age. METHODS: For each hair, the diameter was determined optically andthen the test in the Deform Type 2 testing machine was carried out. Deformationcurves were obtained by testing 10 mm long samples up to the rupture point atconstant temperature, humidity and constant crossbar speed of 2 mm/min. Thecurves were processed with software for the calculation of mechanical parametersof the hairs. This specialized software has been designed by us for that purpose.Resulting values were arranged into tables and figures. RESULTS: As far as haircross-section is concerned, it has been found that for the European populationit appears to be rather higher – 86 μm – than indicated in formerly publishedtexts. The 56 μm mentioned in the work of other authors has been observed onlyutterly exceptionally, in 0.3 % of the population. All quantities studied (exceptextensibility) display moderate to strong positive skewness in comparison toGauss distribution. The most marked skewness is seen in the resilience. At thesame time, this quantity displays the highest value of non-Gaussian distribution.The elasticity module of 2.3±0.6 GPa is three times lower than the one reportedby other authors, yet according to the fact published in our work – which showsunambiguously that the thinner the hair, the higher elasticity module it displays– the value of 7.2 GPa for the 56 μm thick hairs is comparable and it confirms thehypothesis that the cortex, which is responsible for the mechanical strength of thehair, is contained in a higher ratio in thinner hairs. This similarly applies to theultimate strength; the linearity limit is hard to compare with literature, as it almostdoes not appear there. CONCLUSION: By measuring 886 samples from the headsof 60 adult women of European type, it was possible to ascertain the current normfor a larger number of mechanical parameters of the hairs. Further merit of thiswork is the fact that the hairs were taken systematically from five well-definedplaces of the studied heads in equal count, which is an aspect formerly publishedworks do not respect and they do not present the location of sampling.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

30202 - Endocrinology and metabolism (including diabetes, hormones)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Neuroendocrinology Letters

ISSN

0172-780X

e-ISSN

—

Svazek periodika

38

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

SE - Švédské království

Počet stran výsledku

9

Strana od-do

199-207

Kód UT WoS článku

000406690100011

EID výsledku v databázi Scopus

2-s2.0-85045195589