Physical characterization of the hair of Mexican women.

Hairs collected from 257 Mexican women, residing in Mexico City, were characterized by instrumental measurements for comparison to more-commonly reported Caucasian, Asian and African hairs. Subjects were subdivided into five age groups and their hairs were characterized by fibre dimension, shape and tensile strength. Results show that Mexican hair appears to be intermediate of Asian and Caucasian hair in diameter and cross-sectional ellipticity. Such findings seem in line with the early and late ethnic origins of Mexican people. Results also illustrate and confirm the large intra- and inter-individual variability within any single hair property. Unexpectedly high levels of hair tensile damage were sometimes encountered.

Des cheveux prélevés sur 257 mexicaines, résidant dans la ville de Mexico, ont été mesurés et comparés avec des cheveux caucasiens, asiatiques et africains, généralement mieux connus. Les sujets ont été répartis en 5 catégories d'âge et leurs cheveux caractérisés selon la dimension de la fibre, leur forme et leur résistance mécanique. Les résultats montrent que les cheveux mexicains se situent, en termes de diamètre et d'ellipticité, entre les asiatiques et les caucasiens. Cela semble en cohérence avec les origines ethniques récentes et anciennes du peuple mexicain. Les résultats illustrent aussi et confirment la grande diversité intra et inter individu pour toutes les propriétés du cheveu. Des cheveux anormalement fragiles lorsque soumis à un test de tension ont parfois été rencontrés.

Morphological criteria of feminine upper eyelashes, quantified by a new semi-automatized image analysis: Application to the objective assessment of mascaras.

BACKGROUND: The wide diversity of feminine eyelashes in shape, length, and curvature makes it a complex domain that remains to be quantified in vivo, together with their changes brought by application of mascaras that are visually assessed by women themselves or make-up experts. METHODS: A dedicated software was developed to semi-automatically extract and quantify, from digital images (frontal and lateral pictures), the major parameters of feminine eyelashes of Mexican and Caucasian women and to record the changes brought by the applications of various mascaras and their brushes, being self or professionally applied. RESULTS: The diversity of feminine eyelashes appears as a major influencing factor in the application of mascaras and their related results. Eight marketed mascaras and their respective brushes were tested and their quantitative profiles, in terms of coverage, morphology, or curvature were assessed. Standard applications by trained aestheticians led to higher and more homogeneous deposits of mascara, as compared to those resulting from self-applications. CONCLUSION: The developed software appears a precious tool for both quantifying the major characteristics of eyelashes and assessing the making-up results brought by mascaras and their associated brushes.

In vivo evaluation of some biophysical parameters of the facial skin of Indian subjects living in Mumbai. Part II: Variability with age and gender.

BACKGROUND: A previously published work explored the diversity of some biophysical parameters (colour, elasticity, sebum production, skin microrelief, etc.) of the skin of 1204 Indian women, differently aged, living in four Indian cities (Chennai, Delhi, Kolkata and Mumbai). The present work aimed at completing such research by focusing on possible gender-related differences in the same skin parameters, between Indian men and women living in the same Indian city (Mumbai). METHODS: A total of 297 Indian men, differently aged (18-70y), were recruited in Mumbai, completing the panel of 303 women who were previously recruited in this same city. The same instrumental measurements of facial skin colour and its homogeneity, its mechanical properties, the sebum production, skin pores size, skin relief, etc. as in the previous work, were conducted. RESULTS: Overall, the facial skin colour shows a darker complexion in men as compared to women, on forehead, ocular region, lips, chin and cheek. The skin colour unevenness, which increases with age, was found higher in men, as compared to women. At comparable age, women and men present a same density of skin pores, whereas those of men appear larger, up to 55y. The deepness of Crow's feet wrinkles does not significantly differ between genders. A lesser extensibility was found on the cheeks of men. In men, the sebum production was found significantly higher than that of women at ages above 40y. CONCLUSIONS: This work indicates some commonly shared age-related skin features between women and men from Mumbai, despite slight different characteristics such as skin pigmentation, forehead/cheek colour contrast, mechanical properties and sebum production.