About Photo-damage Of Human Hair

This paper reviews the current knowledge about human hair photodamage and the photodegradation mechanisms proposed in the literature. It is shown that there are still a number of questions without answer regarding this issue. For example, a better understanding of the hair structural changes caused by different radiation wavelengths is still lacking. We also find controversies about the effects of sun exposure on different hair types. Explanations to these questions are frequently sustained on the amount and type of melanin of each hair, but factors such as the absence of knowledge of melanin structure and of established methodologies to use in human hair studies make it difficult to reach a general agreement on these issues. © The Royal Society of Chemistry and Owner Societies 2006.52165169Hoting, E., Zimmermann, M., Hocker, H., Photochemical alterations on human hair. Part II. Analysis of melanin (1995) J. Soc. Cosmet. Chem., 46, pp. 181-190Pande, C.M., Jachowicz, J., Hair photodamage: Measurement and prevention (1998) J. Soc. Cosmet. Chem., 49, pp. 309-320Ultraviolet Radiation (1994) Environmental Health Criteria 160, , World Health OrganizationOzeki, Ito, S., Wakamatsu, K., Chemical Characterization of melanins in sheep wool and human hair (1996) Pigm. Cell Res., 9 (2), pp. 51-57Borges, C.R., Roberts, J.C., Wilkins, D.G., Rollins, D.E., Relationship of melanin degradation products to actual melanin content. Application to human hair (2001) Anal. Biochem., 290, pp. 116-125Borovansky, J., Elleder, M., Melanosome Degradation: Fact or Fiction (2003) Pigm. Cell Res., 16, pp. 280-286Pfau, A., Hössel, P., Vogt, S., Sander, R., Schrepp, W., The interaction of cationic polymers with human hair (1997) Macromol. Symp., 126, pp. 241-252Smith, G.J., New trends in photobiology: Photodegradation of keratin and other structural proteins (1995) J. Photochem. Photobiol., B, 27, pp. 187-198Robbins, C.R., (2002) Chemical and Physical Behavior of Human Hair, , Springer-Verlag, New York, 4th ednZuidema, P., Govaert, L.E., Baaijens, F.P.T., Ackermans, P.A.J., Asvadi, S., The influence of humidity on the viscoelastic bahaviour of human hair (2003) Biorheology, 40, pp. 431-439Barnicot, N.A., Birbeck, M.S.C., The electron microscopy of human melanocytes and melanin granules (1958) The Biology of Hair Growth, pp. 239-252. , ed. W. Montagna and R. A. Ellis, Academic Press, New YorkVan Der Mei, I.A.F., Blizzard, L., Stankovich, J., Ponsonby, A.-L., Dwyer, T., Misclassification due to body hair a seasonal variation on melanin density estimates for skin type using spectrophotometry (2002) J. Photochem. Photobiol., B, 68, pp. 45-52Draelos, Z.D., The biology of hair care (2000) Dermatol. Clin., 18, pp. 651-658Wolfram, L.J., Human hair: A unique physicochemical composite (2003) J. Am. Acad. Dermatol., 48, pp. S106-S114Sarna, T., Sealy, R.C., Photoinduced oxygen consumption in melanin systems. Action spectra and quantum yields for eumelanin and synthetic melanin (1984) Photochem. Photobiol., 39, pp. 69-74Nogueira, A.C.S., Joekes, I., Hair color changes and protein damage caused by ultraviolet radiation (2004) J. Photochem. Photobiol., B, 74 (2-3), pp. 109-117Bruls, W.A.G., Slaper, H., Van Der Leun, J.C., Berrens, L., Transmission of human epidermis and stratum corneum as a function of thickness in the ultraviolet and visible regions (1984) Photochem. Photobiol., 40 (4), pp. 485-494Braida, D., Dubief, C., Lang, G., Photoageing of hair fiber and photoprotection (1994) Skin Pharmacol., 7 (1-2), pp. 73-77Signori, V., Review of the current understanding of the effect of ultraviolet and visible radiation on hair structure and options for photoprotection (2004) J. Cosmet. Sci., 55, pp. 95-113Ratnapandian, S., Warner, S.B., Kamath, Y.K., Photodegradation of human hair (1998) J. Cosmet. Sci., 49, pp. 309-320Ruetsch, S.B., Kamath, Y., Weigmann, H., Photodegradation of human hair: A microscopy study (2001) Sun Protection in Man, pp. 175-205. , ed. P. U. Giacomoni, Elsevier, AmsterdamCheun, W.L., The chemical structure of melanin (2004) Pigm. Cell Res., 17, pp. 422-424Prota, G., (1992) Melanins and Melanogenesis, , Academic Press Inc, LondonMargalith, P.Z., (1992) Pigment Microbiology, , Chapman and Hall, LondonTolgyesi, E., Weathering of hair (1983) Cosmet. Toiletries, 98, pp. 29-33Agache, P.G., Quencez, E., The mechanism of solar erythema (1988) J. Appl. Cosmetol., 6, pp. 69-78Draelos, Z.D., The biology of hair care (2000) Dermatol. Clin., 18, pp. 651-658Andrady, A.L., Hamid, S.H., Hu, X., Torikai, A., Effects of increased solar ultraviolet radiation on materials (1998) J. Photochem. Photobiol., B, 46, pp. 96-103Müller, U., Rätzsch, M., Schwanninger, M., Steiner, M., Zöbl, H., Yellowing and IR-changes of spruce wood as result of UV-irradiation (2003) J. Photochem. Photobiol., B, 69, pp. 97-105O'Connell, R.A., Walden, M.K., Influence of ionizing radiation on wool fiber properties (1957) Text. Res. J., 27, pp. 516-518Jones, D.C., Carr, C.M., Cooke, W.D., Lewis, D.M., Investigating the photo-oxidation of wool using FT-Raman and FT-IR spectroscopies (1998) Text. Res. J., 68, pp. 739-748Dunlop, J.I., Nicholls, C.H., Electron spin resonance studies of ultraviolet irradiated keratin and related proteins (1965) Photochem. Photobiol., 4, pp. 881-890Davidson, R.S., The photodegradation of some naturally occurring polymers (1996) J. Photochem. Photobiol., B, 33, pp. 3-25Smith, G.J., The effect of light at different wavelengths on electron spin resonance in wool (1976) Text. Res. J., 46, pp. 510-513Smith, G.J., Claridge, R.F.C., Smith, C.J., The action spectra of free radicals produced by the irradiation of keratin containing bound iron(III) ions (1979) Photochem. Photobiol., 29, pp. 777-779Millington, K.R., Church, J.S., The photodegradation of wool keratin II. Proposed mechanisms involving cystine (1997) J. Photochem. Photobiol., B, 39, pp. 204-212Bertazzo, A., Biasiolo, M., Costa, C.V.L., Stefani, E.C., Allegri, G., Tryptophan in human hair: Correlation with pigmentation (2000) Farmaco, 55, pp. 521-525Vincensi, M.R., D'Ischia, M., Napolitano, A., Procaccini, E.M., Riccio, G., Monfrecola, G., Santoianni, P., Prota, G., Phaomelanin versus eumelanin as a chemical indicator of ultraviolet sensitivity in fair-skinned subjects at high risk for melanoma: A pilot study (1998) Melanoma Res., 8, pp. 53-58Liu, Y., Simon, J.D., Isolation and biophysical studies of natural eumelanins: Applications of imaging technologies and ultrafast spectroscopy (2003) Pigm. Cell Res., 16, pp. 606-618Keis, K., Ramaprasad, K.R., Kamath, Y.K., Effect of hair color on luster (2004) J. Cosmet. Sci., 55, pp. 423-436Peterson, L.G., A simplification of the protein assay method of Lowry et al., which is more generally applicable (1977) Anal. Biochem., 83, pp. 346-356Lowry, O.H., Rosebrough, N.J., Farr, A.L., Randall, R.J., Protein measurement with the folin phenol reagent (1951) J. Biol. Chem., 193, pp. 265-275Hearle, J.W.S., A critical review of the structural mechanics of wool and hair fibers (2000) Int. J. Biol. Macromol., 27, p. 123Scanavez, C., Zoega, M., Barbosa, A., Joekes, I., Measurement of hair luster by diffuse reflectance spectrophotometry (2000) J. Cosmet. Sci., 51, pp. 289-302Reich, C., Robbins, C.R., Light scattering and shine measurements of human hair: A sensitive probe of the hair surface (1993) J. Soc. Cosmet. Chem., 44, pp. 221-234Tango, Y., Schimmoto, K., Development of a device to measure human hair luster (2001) J. Cosmet. Sci., 52, pp. 237-25

Tire Rubber-cement Composites: Effect Of Slag On Properties [compósites De Cimento - Borracha De Pneus: Efeito Da Escória Nas Propriedades]

Tire rubber-cement composites prepared with type I and three slag-modified cements were studied. Flexural strength, water sorption and resistance to acid attack of specimens were investigated. A decrease in modulus of rupture (MOR) is observed for all specimens containing rubber, when compared with specimens without rubber (controls). The MOR increases with the increase of the hydraulic activity of the slag upon undistinguishable from specimens prepared with type I cement. This behavior is observed for all slag-cements pastes and for mortars control specimens. For mortar specimens with rubber the MOR is independent of the cement type used. A reduction in water sorption is observed for control and with-rubber mortar specimens prepared with all slag-cements, when compared to type I cement. For mortar specimens with rubber, the lower the basicity of the slag, the lesser the water sorption of the composites. These results denote lower porosity and consequently better rubber-matrix adhesion for these specimens. Also, a smaller rate of water sorption is observed for specimens with rubber, particularly for specimens prepared with the less basic slag cements, when comparing with the controls. Results of acid attack to the slag modified mortars indicate that specimen susceptibility is governed not only by microstructural aspects, like porosity and permeability, but also by chemical aspects as the difference in alkali content or the amount of unreacted slag in the specimens.52324283292Lee, B.I., Burnett, L., Miller, T., Postage, P., Cuneo, J., (1993) J. Mater. Sci. Lett, 12, p. 967I. B. Topçu, Gem. Conor. Res. 25 (1995) 304Raghavan, D., Huynh, H., Ferraris, C.F., (1998) J. Mater. Sci, 33, p. 1745Bignozzi, M.C., Saccani, A., Sandrolini, F., (2000) Composites A, 31, p. 97Raghavan, D., (2000) J. Appl. Polym. Sci, 77, p. 934M. Nehdi, A. Khan, Cem. Concr. Aggregates 23 (2001) 3Hernandez-Olivares, F., Barluenga, G., Bollati, M., Witoszek, B., (2002) Cem. Concr. Res, 32, p. 1587N. Segre, I. Joekes, Gem. Concr. Res. 30 (2000) 1421(2001) Lea's Chemistry of Cement and Concrete, , P. C. Hewlett Ed, 4 th Ed, Butterworth Heinemann, OxfordMyers, D., (1999) Surfaces, Interfaces, and Colloids-Principles and Applications, , 2nd Ed, John Wiley & Sons, New YorkBikerman, J.J., (1961) The Science of Adhesive Joints, , Academic Press, New YorkMindess, S., Interfaces in concrete (1989) Materials Science of Concrete I, p. 163. , J.P. Skalny Ed, The Am. Ceram. Soc, Westerville, OHLuke, K., Glasser, F.P., (1987) Cem. Concr. Res, 17, p. 273M. A. Cincotto, A. F. Battagin, V. Agopyan, Bulletin 65, Ed.: Institute for Technological Research, IPT, S. Paulo, Brazil (1992)ASTM C150 - Standard specification for Portland cement, American Society for Testing and Materials (1995)- Standard specification for blended hydraulic cements (1994), ASTM C595, American Society for Testing and MaterialsMindess, S., Young, J.F., (1981) Concrete, , Prentice-Hall, Englewood Cliffs, New JerseyMehta, P.K., Monteiro, P.J.M., (1993) Concrete: Structure, Properties and Materials, , 2nd Ed, Prentice-Hall, Englewood Cliffs, New JerseyGriffith, A.A., (1920) Phil. Trans. R. Soc. Lond. A, 221, p. 163Birchall, J.D., Howard, A.J., Kendall, K., (1981) Nature, 289, p. 388Martins, M.A., Mattoso, L.H.C., (2004) J. Appl. Polym. Sci, 91, p. 670Lumley, J.S., Gollop, R.S., Moir, G.K., Taylor, H.F.W., (1996) Cem. Concr. Res, 26, p. 139Glasser, F.P., Chemical, mineralogical, and microstructural changes occurring in hydrates slag-cement blends (1991) Materials Science of Concrete II, p. 41. , J. P. Skalny, S. Mindess Eds, The Am. Ceram. Soc, Westerville, OHSegre, N., Monteiro, P.J.M., Sposito, G., (2002) J. Colloid Interface Sci, 248, p. 521Falcon, P., Adenot, F., Jacquinot, J.F., Petit, J.C., Cabrillac, R., Jordas, M., (1998) Cem. Conor. Res, 28, p. 847Israel, D., Macphee, D.E., Lachowski, E.E., (1997) J. Mater. Sci, 32, p. 4109Chandra, S., (1988) Cem. Conor. Res, 18, p. 193Zivica, V., Bajza, A., (2001) Constr. Build. Mater, 15, p. 331Pavlik, V., (1994) Cem. Conor. Res, 24, pp. 551-562Debelie, N., Verselder, H.J., Deblaere, B., Vannieuwenburg, D., Verschoore, R., (1996) Cem. Conor. Res, 26, p. 1717Shi, C., Stegemann, J.A., (2000) Cem. Conor. Res, 30, p. 803Zivica, V., Bajza, A., (2002) Constr. Build. Mater, 16, p. 215Deceukelaire, L., (1992) Cem. Conor. Res, 22, p. 903A. Macias, S. Goni, J. Madrid, Cem. Conor. Res. 29 (1999) 2005J. Hill, E. A. Byars, J. H. Sharp, C. J. Lynsdale, J. C. Cripps, Q. Zhou, Cem. Conor. Compos. 25 (2003) 997Hobbs, D.W., (2001) Int. Mater. Rev, 46, p. 11

A critical analysis of user satisfaction surveys in addiction services: Opioid maintenance treatment as a representative case study

Background: Satisfaction with services represents a key component of the user's perspective, and user satisfaction surveys are the most commonly used approach to evaluate the aforementioned perspective. The aim of this discursive paper is to provide a critical overview of user satisfaction surveys in addiction treatment and harm reduction services, with a particular focus on opioid maintenance treatment as a representative case. Methods: We carried out a selective critical review and analysis of the literature on user satisfaction surveys in addiction treatment and harm reduction services. Results: Most studies that have reported results of satisfaction surveys have found that the great majority of users (virtually all, in many cases) are highly satisfied with the services received. However, when these results are compared to the findings of studies that use different methodologies to explore the patient's perspective, the results are not as consistent as might be expected. It is not uncommon to find that "highly satisfied" patients report significant problems when mixed-methods studies are conducted. To understand this apparent contradiction, we explored two distinct (though not mutually exclusive) lines of reasoning, one of which concerns conceptual aspects and the other, methodological questions. Conclusion: User satisfaction surveys, as currently designed and carried out in addiction treatment and harm reduction services, do not significantly help to improve service quality. Therefore, most of the enthusiasm and naiveté with which satisfaction surveys are currently performed and interpreted - and rarely acted on in the case of nonoptimal results - should be avoided. A truly participatory approach to program evaluation is urgently needed to reshape and transform patient satisfaction surveys. Keywords: patient satisfaction, substance abuse treatment services, harm reduction services, patient-centered evaluation, service user perspective, user involvemen

Youth as Actors of Change? The Cases of Morocco and Tunisia

In the last decades, ‘youth’ has increasingly become a fashionable category in academic and development literature and a key development (or security) priority. However, beyond its biological attributes, youth is a socially constructed category and also one that tends to be featured in times of drastic social change. As the history of the category shows in both Morocco and Tunisia, youth can represent the wished-for model of future citizenry and a symbol of renovation, or its ‘not-yet-adult’ status which still requires guidance and protection can be used as a justification for increased social control and repression of broader social mobilisation. Furthermore, when used as a homogeneous and undifferentiated category, the reference to youth can divert attention away from other social divides such as class in highly unequal societies

Use of chrysotile fibres in the degradation of cationic and nonionic surfactants in aqueous solutions

It was previously observed that sodium dodecylbenzenesulfonate (SDBS) is degraded in the presence of chrysotile fibres. A higher catalytic efficiency was obtained than the reported values for TiO2 under the same conditions. Chrysotile, a clay mineral fibre of low cost and relatively abundant, probably acts as a catalyst through an Advanced Oxidative Process (AOP) involving free radical formation. In this work, experiments with non-ionic - Triton X-45 (octil-phenoxy polyethoxy ethanol) - and cationic - Herquat 3500 (alkyl dimethyl benzyl ammonium chloride) - surfactants were carried out. Diluted aqueous solutions (50 ppm) of these surfactants were kept in contact with chrysotile (4.0 g) in the dark at room temperature. The aromatic ring disappearance was followed through the absorbance peaks at 224 nin (Triton X-45) and 208 nin (Herquat 3500) in the UV spectra. After 4 h, reductions in the surfactant solution concentration of 65.0% and 35.0% were observed for the Triton X-45 and the Herquat 3500 surfactants, respectively. In both cases, reactions carried out without aeration showed a lower reduction of the aromatic ring concentration (30.0% less) when compared to the values obtained for the systems with airflow. The system containing the non-ionic surfactant seems to achieve equilibrium after 2 It, what is not observed for the cationic surfactant system.o TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE AGOSTO DE 2015.35110010

Tire rubber-sisal composites: Effect of mercerization and acetylation on reinforcement

Tire rubber particles were mixed randomly with short sisal fibers and hot pressed. Sisal fibers were used as received, mercerized, and mercerized/acetylated. The fibers were characterized by scanning electron microscopy (SEM), thermal gravimetry analysis (TGA), infrared spectroscopy (FTIR), water sorption, and mechanical properties. Thermal stability of the mercerized/acetylated fibers improves (from 200 to 300degreesC) with respect to the raw fibers, and water sorption is similar to20% smaller than for the raw and the mercerized fibers. Tensile strength is unchanged after the chemical treatments. Water sorption, mechanical properties, and SEM evaluated the performance of the tire rubber composites. All composites showed enhanced elastic modulus; increase is dependent on fiber load. Smallest water sorption was obtained in composites with the mercerized/acetylated fibers. With these fibers at 10% load, the best results were obtained with the smaller tire rubber particles (320 mum) and at 5% load with the bigger (740 mum) tire rubber particles. Both composites showed similar to50% increase in tensile strength when compared to similar composites with raw fibers. SEM of the surface of fracture showed that the adhesion between fiber and rubber was enhanced after both chemical treatments. (C) 2003 Wiley Periodicals, Inc.8992507251

OSMOSEDIMENTATION EQUILIBRIUM UNDER GRAVITY - AVERAGE MOLECULAR-WEIGHTS AND 2ND VIRIAL-COEFFICIENT OF AQUEOUS SILVER SOLS

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Rhodamine B diffusion in hair as a probe for structural integrity

The aim of this work was to investigate the diffusion of Rhodamine B into bleached, photo bleached and abraded hair, treated or not with an emulsion of ceramide using two different techniques: spectrophotometry and fluorescence optical microscopy with image analysis. This comparison, combined with the Einstein-Smoluchowski equation, allowed validating a methodology that uses the apparent diffusion coefficient of a dye as an index for hair damage. Distinct behaviors of the dye were observed in the cuticle and in the cortex. For a bleached hair sample the apparent diffusion coefficient in the cuticle ranges from 8.2 x 10(-11) cm(2) s(-1) to 10 x 10(-11) cm(2) s(-1), while for the cones this value drops to 4.0 x 10(-11) cm(2) s(-1) to 4.2 x 10(-11) cm(2) s(-1). The diffusion is always faster in the cuticle than in the cortex and the apparent diffusion coefficient shows up to a seven-fold decrease when the dye penetrates the cortex. The chemical, photochemical and physical treatments applied to hair significantly change the values of the apparent diffusion coefficients in the cuticle. The data also proved eh at the penetration of Rhodamine B into hair occurs via an intercellular path. (C) 2004 Elsevier B.V. All rights reserved.401192