Does straight-hair nevus exist?

AbstractRecent studies in Asian populations have identified variants in theEDARandFGFR2genes that arose following the divergence of Asians and Europeans and are associated with thick straight hair. To date no genetic variants have been identified influencing hair texture in Europeans. In the current study we examined the heritability of hair curliness in three unselected samples of predominantly European ancestry (NS1= 2717;NS2= 3904;NS3= 5079). When rated using a three point scale (Straight/Wavy/Curly) males were ~5% more likely to report straight hair than females and there were suggestions in the data that curliness increased slightly with age. Across samples significant additive and dominant genetic influences were detected resulting in a broad sense heritability of 85–95%. Given the magnitude and the specificity of the EDAR effect on hair morphology in Asian populations we are hopeful that future association studies will detect similar genetic influences in European populations.

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Why does curly hair get less tangled than straight hair?

American Journal of Physics ◽

10.1119/1.2733683 ◽

2007 ◽

Vol 75 (8) ◽

pp. 701-706

Author(s):

Jean-Baptiste Masson

Keyword(s):

Curly Hair ◽

Straight Hair

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Straight hair associated with interferon-alfa plus ribavirin in hepatitis C infection

British Journal of Dermatology ◽

10.1046/j.1365-2133.2002.48215.x ◽

2002 ◽

Vol 147 (2) ◽

pp. 392-392 ◽

Cited By ~ 28

Author(s):

D. Bessis ◽

M.S. Luong ◽

P. Blanc ◽

C. Chapoutot ◽

D. Larrey ◽

...

Keyword(s):

Hepatitis C ◽

Interferon Alfa ◽

Hepatitis C Infection ◽

Straight Hair

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Variation in the RPTN gene may facilitate straight hair formation in Europeans and East Asians

Journal of Dermatological Science ◽

10.1016/j.jdermsci.2018.06.003 ◽

2018 ◽

Vol 91 (3) ◽

pp. 331-334 ◽

Cited By ~ 3

Author(s):

Ewelina Pośpiech ◽

Soong Deok Lee ◽

Magdalena Kukla-Bartoszek ◽

Joanna Karłowska-Pik ◽

Anna Woźniak ◽

...

Keyword(s):

East Asians ◽

Straight Hair ◽

Hair Formation

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The adaptive variant EDARV370A is associated with straight hair in East Asians

Human Genetics ◽

10.1007/s00439-013-1324-1 ◽

2013 ◽

Vol 132 (10) ◽

pp. 1187-1191 ◽

Cited By ~ 42

Author(s):

Jingze Tan ◽

Yajun Yang ◽

Kun Tang ◽

Pardis C. Sabeti ◽

Li Jin ◽

...

Keyword(s):

East Asians ◽

Straight Hair

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On elastic growth modelling of straight hair

Mathematics and Mechanics of Solids ◽

10.1177/1081286516680392 ◽

2017 ◽

Vol 23 (2) ◽

pp. 221-232

Author(s):

Kostas P Soldatos

Keyword(s):

Soft Tissue ◽

Hair Follicle ◽

Transversely Isotropic ◽

Small Strain ◽

Growth Conditions ◽

Hair Shaft ◽

Mass Growth ◽

Hair Matrix ◽

Straight Hair ◽

Hair Fibre

Certain macroscopic similarities of the nail and hair elongation mechanisms enable the mass-growth activity that takes place within a straight hair follicle to be modelled through a suitable extension of a relevant small-strain pseudo-elasticity model of human nail growth. Basic differences which are taken into consideration are the facts that straight hair (a) resembles the form of a cylindrical rod, rather than a plate, while (b) its material constitution seems microscopically transversely isotropic, rather than isotropic. A complete analytical solution of the obtained governing differential equations is detailed for the case where incompressible mass-growth conditions prevail within the hair matrix. In addition to estimating displacement and stress distributions that develop within the growing matrix, and the resulting hair elongation, that solution enables prediction of a clinically observed zone of hair-fibre hardening that lies between the matrix soft tissue and the hard keratinous hair shaft. It also predicts that the longitudinal dimension of the hair matrix and that of the hair-fibre hardening zone depend on the material properties of the soft tissue of the follicle. Consideration of more advanced micro- or macro-scopic features of the hair follicle, such as layered structure or curved form, can be handled mathematically in a similar manner at the expense of analytical simplicity.

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A Curly Q: Is Frizz a Matter of Friction?

Perception ◽

10.1177/03010066211024442 ◽

2021 ◽

pp. 030100662110244

Author(s):

Lisa Skedung ◽

Elizabeth S. Collier ◽

Kathryn L. Harris ◽

Mark W. Rutland ◽

Mara Applebaum ◽

...

Keyword(s):

Elevated Temperature ◽

Environmental Influences ◽

Tactile Perception ◽

Temperature And Humidity ◽

Curly Hair ◽

Straight Hair ◽

Tactile Friction

The oft discussed and fretted over environmental influences on hair have led to a popular consensus which suggests that elevated temperature and humidity lead to frizzier, wilder hair. However, few attempts at actually quantifying these effects have been made. Although frizziness is usually perceived visually, here the influence of variations in temperature and humidity on the tactile perception and friction of curly and straight hair were investigated. It is shown that changes in humidity may disproportionately affect perceived frizziness of curly hair by touch due to concurrent changes in the tactile friction.

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Leśmian’s dziwożonas and their Slavic contexts (literary and not only)

Tekstualia ◽

10.5604/01.3001.0013.3112 ◽

2018 ◽

Vol 1 (52) ◽

pp. 89-100

Author(s):

Żaneta Nalewajk–Turecka

Keyword(s):

20Th Century ◽

Frame Of Reference ◽

Literary Texts ◽

Female Characters ◽

Straight Hair

Among the literary female characters to be found in Bolesław Leśmian’s writing, there are dzwiożonas – swamp or forest demons from the Slavic mythology, known as malicious and dangerous creatures that kidnapped babies just after they were born and replaced them with her own children. They were often portrayed as wild women with long, straight hair and breasts so huge that they could use them to wash their clothes. A survey of selected literary texts from the 19th and the beginning of the 20th century by Polish (Seweryn Goszczyński, Michał Bałucki, Miron [Aleksander Michaux], Maria Konopnicka, Kazimierz Przerwa-Tetmajer, Wiktor Gomulicki), Czech (Karel Jaromír Erben) and Russian (Konstantin Balmont) writers, shows how the representation of such female demons evolved and provides a frame of reference for Bolesław Leśmian’s portrayal of analogous characters in his poem Dziwożona and in prose work Podlasiak from the volume entitled Klechdy polskie.

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A Portrait of Ptolemy III Euergetes

The Journal of Hellenic Studies ◽

10.2307/626392 ◽

1933 ◽

Vol 53 (2) ◽

pp. 300-300

Author(s):

R. P. Hinks

Keyword(s):

British Museum ◽

Flat Background ◽

Middlesex Hospital ◽

The Face ◽

Straight Hair ◽

Bright Blue

A small glazed earthenware portrait-head of a man, found accidentally on the site of the Middlesex Hospital, has been acquired by the Department of Greek and Roman Antiquities at the British Museum, as a gift from Mr. C. E. Grunspan. It is 32 millimetres (1 3/16 inches) in height; and is made of buff clay, covered all over with a vitreous glaze which varies in colour from brownish-green to bright blue. The neck is broken off from the nape to the base of the chin. The back of the head is cut off obliquely, but evenly, as though for attachment to a flat background; the oblique cut gives the face a quarter turn to the left. The head is hollowed out behind, and even this cavity is blue-glazed.The man represented has a fleshy jowl, rather projecting lips, prominent eyes, and a somewhat retreating forehead, over which the straight hair is combed forward in a roll, held in position by a plain rounded diadem.

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