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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Determinação eletroanalítica de corantes de cabelos temporários em água, tintura comercial e fio de cabelo usando eletrodo compósito e partículas magnéticas modificadas com carbolixatos /

Corrêa, Gláucia Tinoco. January 2017 (has links)
Orientador: Maria Valnice Boldrin Zanoni / Resumo: Corantes de cabelo, provenientes principalmente da tintura comercial de cabelo em salões de beleza, quando não convenientemente descartados, podem gerar efluentes de difícil tratamento. Além disso, a análise de corante de cabelo em fios de cabelo tingidos, poderia favorecer informações úteis para análise forense. Em virtude de alto consumo de corantes de cabelo, que podem ser encontrados na forma de tinturas permanente, semipermantes e temporárias, com diferentes estruturas e comportamento físico-químico, a demanda por métodos analíticos sensíveis e robustos para sua quantificação é altamente pertinente. Diante disso, o presente trabalho descreve a construção de sensores eletroquímicos para quantificação de corantes de cabelo do tipo temporário, pois são classe de corantes facilmente removidos do cabelo e, consequentemente, podem ser liberados para o meio ambiente. O sensor eletroquímico consiste no desenvolvimento de um eletrodo compósito com partículas magnéticas modificadas como grupos carboxílicos (CFMP) para determinação dos corantes basic brown 16 (BB16), basic red 51 (BR51) e basic yellow 57 (BY57) em amostras de extratos de fios de cabelos, amostras comercias de tintura temporária, água de lavagem, amostras de água de rio e de torneira. Os três corantes apresentam grupos azos como cromóforos. No presente trabalho, investigou-se a oxidação de aminas e hidroxilas presentes como grupos auxocromos nos corantes. Os resultados mostraram que a oxidação do grupo funcional nos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Hair dyes, mainly coming from commercial hair colorants in beauty salons, when not properly discarded, can generate effluents that are difficult to treat. In addition, hair dye analysis in dyed hair strands could be used as useful information for forensic analysis. Due to the high consumption of hair dyes, which can be found in the form of permanent, semipermanent and temporary dye, with different structures and physicochemical behavior, the demand for sensitive and robust analytical methods for their quantification is highly relevant. Therefore, the present work describes the construction of electrochemical sensors for the quantification of hair dyes of the temporary type, because they are class of dyes easily removed from the hair and, consequently, are released in great quantity for the environment. The electrochemical sensor consists of the development of a composite electrode using modified magnetic particles with carboxylic groups (CFMP) to determine the dyes basic brown 16 (BB16), basic red 51 (BR51), and basic yellow 57 (BY57) in samples of yarn extracts Hair samples, commercial samples of temporary tincture, wash water, samples of river water and tap water. The three dyes analyzed have azide groups as chromophores. In the present work, the oxidation of amines and hydroxyls present as auxochromic groups in the dyes was investigated. The results showed that the oxidation of the functional group in the dyes on the composite electrode modified by carboxylic groups can occur in Ea = 0.44 V, Ea = 0.86 V and Ea = 0.65, respectively for the dyes BB16, BR51, and BY57 and the peak current increases significantly with respect to the electrode without modification. The interaction between dye + CFMP was confirmed by UV/Vis and FTIR spectroscopy. Analytical curves for the BB16, BR51, and BY57 dyes were constructed using the optimized conditions in the square wave voltammetry (SWV) technique: pulse frequency... / Doutor
152

Get Out of My Hair

Stratton, Sabra 01 January 2017 (has links)
The documentary, "Get Out of My Hair, " engages in the dialogue of hair removal and its relationship to femininity, specifically looking at how the media has taught young women to fear the affects of puberty. The piece features ten women between the ages of eleven and twenty-two with ranging demographics who are all brought together by their experiences with their body hair. Applying media effects theory and psychoanalytic theory, this project examines how advertising portrayals of female body depilation contribute to the increase in hair removal and further align the concept of femininity with hairlessness.
153

Down to the Roots: A Qualitative Analysis of the Psychological Impacts of Messages Black Women Receive Regarding their Hair

Gillespie, Christian Hope 01 May 2013 (has links)
AN ABSTRACT OF THE DISSERTATION OF CHRISTIAN H. GILLESPIE, for the Doctor of Philosophy degree in PSYCHOLOGY, presented on April 08, 2013, at Southern Illinois University, Carbondale. TITLE: DOWN TO THE ROOTS: A QUALITATIVE ANAYSIS OF THE PSYCHOLOGICAL IMPACTS OF MESSAGES BLACK WOMEN RECIEVE REGARDING THEIR HAIR MAJOR PROFESSOR: Kathleen Chwalisz, Ph.D. Typical Black features such as thick lips, dark skin, and kinky hair have historically been the subject of scrutiny, exploitation, and devaluation in America. Hair is an important aspect of the discourse about the pressure on all women to accommodate to mainstream beauty ideals. However, there are unique pressures that complicate this narrative for Black women, who have to combat both the pressures of racism and sexism. Many African American women have a naturally kinky hair texture that is distinctly different from their Euro-American counterparts, serving as a widely recognized racial identifier (Chapman, 2007). Although there is a growing body of anthologies, essays, documentaries and case studies exploring Black women's unique experiences regarding their hair, there is a dearth of empirical literature, particularly in the field of psychology, exploring the nuances of Black women's hair experiences and subsequent impacts of negative kinky-hair messages on their hair choices, esteem, personal and emotional functioning. Therefore, a Grounded Theory approach using semi-structured individual interviews was used in this qualitative investigation, designed to answer the following research questions: 1. What messages have Black women received about their naturally kinky hair? 2. What emotions or reactions are elicited for Black women regarding their hair? 3. How do Black women respond to and cope with the messages they've received and experiences they've had regarding their natural hair? Nine self-identified African American/Black women were interviewed for this study. During the interview process, participants described the various hair-related experiences they've had in diverse contexts, their emotional responses and reaction to their experiences, and subsequent means of responding and coping with the emotions elicited. A grounded theory approach was used to analyze the data. The grounded theory model that emerged from this study can be characterized as Defining and Being Defined: Black Women's Identity in a Colorist Society. This storyline is reflective of participants' strive toward self-definition (Caldwell, 2000; Tate, 2007), and simultaneous negotiation of the abuse they experienced and anti-Black aesthetic messages they were exposed to regarding their hair. Defining specifically refers to participants strive toward self-definition (i.e., development of a positive image and self concept), and Being Defined refers to their efforts to manage how others in society perceived them (e.g., their attractiveness, competence, femininity etc.) in relation to their hair. The participants' narratives reflected the marginalization, trauma, abuse, and rejection they experienced in relation to their hair and in their personal lives. The Black women also expressed an unyielding sense of optimism, resilience and hope regarding their future experiences.
154

Axillary hair developmental ultrastructure and mucilage composition in the moss Physcomitrella patens: Microscopic and bioinformatic analyses

Piatkowski, Bryan 01 December 2015 (has links)
Physcomitrella patens, a haploid-dominant land plant, has increasingly become useful in molecular genetic studies and is a model for early land plant evolution. This thesis work explores the mucilage secretory hair ontology, development, and ultrastructure with microscopic methods. Axillary hair development parallels that of secretory tissues found in other mosses and ultrastructure shares important similarities with liverwort mucilage papillae. These mucilage secretory structures cover the developing apex and young leaves with mucilage for protection. Changes in the hair cell wall and mucilage secretion are mediated by pectin and wall modification. Using bioinformatic methods, this thesis also investigates protein-protein interactions in Physcomitrella to understand the molecular mechanisms governing pectin biosynthesis and modification.
155

Significado da alopecia para mulheres submetidas à quimioterapia para o câncer ginecológico ou mamário / Meaning of hair loss in women undergoing chemotherapy for breast or gynecological cancer

Barbara Alexandre Lespinassi Sampaio 02 August 2013 (has links)
Estudo qualitativo, cujo objetivo foi compreender o significado da alopecia, decorrente de quimioterapia, para mulheres submetidas a esse tipo de tratamento para o câncer ginecológico ou mamário, e teve como referencial teórico o Interacionismo Simbólico. Os dados foram obtidos por meio de entrevistas e prontuários de 15 mulheres que apresentaram alopecia como evento adverso ao tratamento quimioterápico, e frequentavam um serviço especializado em reabilitação pós-mastectomia ou um ambulatório ou enfermaria de oncologia de um hospital universitário do interior de São Paulo. Foram identificadas duas unidades temáticas pela Análise de Conteúdo: 1) o significado da alopecia para as mulheres que a apresentam, na relação consigo próprias; e 2) na relação com os outros e com o mundo. Na relação consigo próprias, a alopecia significou necessidade de lidar com alterações emocionais e da autoestima, necessidade de disfarce, dificuldade de lidar com a alopecia, de se olhar no espelho e de falar sobre o assunto, sendo que a mulher descobriu formas de lidar com os problemas ocasionados pela queda de cabelo, embora este tenha sido um problema que muitas vezes trouxe sofrimento maior do que o câncer em si. Já na relação com os outros e com o mundo, a alopecia foi tida como um estigma relacionado ao câncer e seus tratamentos, trouxe mudanças nos hábitos e rotinas, além de interferir na sexualidade. Assim, puderam ser identificadas instituições que ofereceram apoio às mulheres. Compreender o significado pleno da experiência de alopecia na vida cotidiana dessas mulheres é fundamental para poder proporcionar-lhes apoio durante o curso da doença, e para auxiliá-las no desenvolvimento de estratégias para lidar com as mudanças que ocorrem durante o tratamento do câncer. / Qualitative study aimed to understand the meaning of hair loss because chemotherapy for women undergoing this type of treatment for breast or gynecological cancer, and had the theoretical Symbolic Interaction. Data were collected through interviews and medical records of15 women who had hair loss as an adverse event to chemotherapy, and attended a specialized rehabilitation postmastectomy or a clinic or oncology ward of a university hospital in São Paulo. Two thematic units were identified by Content Analysis: 1) the meaning of hair loss for women, in relation to themselves, and 2) the relationship with others and with the world. In relation to themselves, hair loss meant the necessity to deal with emotional and self-esteem, the necessity to disguise, difficulty to deal with alopecia, to look in the mirror and talk about it, although the woman discovered ways of dealing with the problems caused by hair loss, this has been a problem that often caused more suffering than the cancer. In the relation with others and with the world, the hair loss was seen as a stigma related to cancer and its treatments, caused changes in habits and routines, as well as interfere with sexuality. Therefore could be identified institutions which offered support for women. Understand the full meaning of the experience of hair loss in women\'s daily life is crucial to be able to provide them support during the course of the disease, and to assist them in developing strategies to deal with the changes that occur during cancer treatment
156

Estudo comparativo da sorção de lipidios em cabelos caucasiano e negroide / Comparative study of the lipid sorption in caucasian and afro hair

Lisboa, Chrislane Pires 28 August 2007 (has links)
Orientador: Ines Joekes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-09T12:53:56Z (GMT). No. of bitstreams: 1 Lisboa_ChrislanePires_M.pdf: 651626 bytes, checksum: 6c05fd4eeebc333924c7e8623de7c98b (MD5) Previous issue date: 2007 / Resumo: Os lipídios são compostos naturalmente presentes no cabelo e possuem importante papel nas suas propriedades. Apesar de serem vastamente utilizados em formulações cosméticas, especialmente naquelas destinadas a cabelos negróides, pouco se estudou sobre a interação desses compostos com a fibra capilar. Neste trabalho foi estudada a interação dos lipídios ácido oléico e colesterol e do composto colato de sódio com cabelo negróide e cabelo caucasiano através da sorção. As mechas de cabelo caucasiano e negróide foram tratadas com soluções de ácido oléico nas concentrações de 0,03 e 0,3 % m/V, nas temperaturas de 25, 40 e 50 °C. A sorção foi calculada pela diferença entre as concentrações inicial e final das soluções por titrimetria. O colesterol foi utilizado nas concentrações de 0,18 e 0,25 % m/V a 25 e 40 °C e sua concentração foi determinada pela absorção em l = 450 nm. A sorção do colato de sódio foi avaliada semi-quantitativamente pela presença do colato na superfície das fibras através da absorção na região do infravermelho utilizando acessório de ATR. A sorção de ácido oléico em cabelo negróide foi duas vezes maior (40 mg/g) do que em cabelo caucasiano (23 mg/g). O colesterol não foi sorvido pelo cabelo negróide e nem pelo cabelo caucasiano. A sorção do colato de sódio foi maior em cabelo negróide do que no cabelo caucasiano em concordância com o tratamento com ácido oléico. O processo de sorção foi favorecido em maiores concentrações dos lipídios e em temperatura de 25 °C. O tamanho e a polaridade da molécula e o solvente onde ela se encontra foram fatores determinantes para a sorção em cabelo. A maior sorção do ácido oléico e do colato de sódio em cabelo negróide do que em cabelo caucasiano evidenciam as diferenças físico-químicas desses dois tipos de cabelo e deve estar relacionada a menor concentração lipídica do cabelo negróide / Abstract: Lipids are compounds naturally present in human hair and play an important role in its properties. Despite of being vastly used in cosmetic formulations, especially in those destined to Afro hair, little attention has been dedicated to the study of the interaction of lipids with the hair fiber. In this work it was studied the interaction of oleic acid and cholesterol and the compound sodium cholate with Afro and Caucasian hair through the sorption process. Caucasian and Afro hair tresses were treated with 0,03 and 0,3 % m/V solutions of oleic acid at 25, 40 and 50 °C. The sorption was calculated by the difference between the final and initial concentrations determined by titrimetry. The cholesterol was used in 0,18 and 0,25 % m/V concentrations at 25 and 40 °C and its bulk concentration was determined by the absorption at l = 450 nm. The sorption of sodium cholate was evaluated by its presence on the surface of the fibers through the absorption in the infrared region using the ATR accessory. The oleic acid sorption was relatively high in both types of hair (S> 20 mg/g) and the sorption was twice larger in Afro hair than (S~ 40 mg/g) in Caucasian hair (S~23 mg/g). The cholesterol was not sorbed by Afro hair and nor in Caucasian hair. The sorption of the sodium cholate was larger in Afro hair than in Caucasian hair in agreement with the oleic acid treatment. The results indicated that the sorption process was favored in higher lipids concentrations and at T = 25 °C. The size and the polarity of the lipid molecule and its solvent were determinant in the sorption process in hair. The differences among the sorption of the oleic acid and the sodium cholate in Afro and in Caucasian hair highlight the physical-chemistry distinction of these types of hair / Mestrado / Físico-Química / Mestre em Química
157

Propagação espacial de epidemias: Threshold e ondas viajantes

ROSA, Wallisom da Silva January 2005 (has links)
Made available in DSpace on 2014-06-12T18:32:22Z (GMT). No. of bitstreams: 2 arquivo8543_1.pdf: 1297134 bytes, checksum: 7faa5a0659773d4b7963a19daf8ad9ac (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2005 / Uma equação integral não linear do tipo mista Volterra - Fredholm descrevendo a propagação espacial de uma epidemia é desenvolvida e analisada. Uma atenção especial é dada ao efeito hair-trigger, onde demonstramos o Teorema do Threshold Pandêmico de Kendall. Outro enfoque importante é o problema das ondas viajantes, onde analisamos como as soluções da equação integral se aproximam da distribuição final. A referência principal do trabalho é o artigo [1] Thresholds and travelling waves for the geographical spread of infection", de O. Diekmann
158

Super-Helices for Hair Modeling and Dynamics

Bergbom, Mattias January 2007 (has links)
We present core components of a hair modeling and dynamics solution for the feature film industry. Recent research results in hair simulation are exploited as a dynamics model based on solving the Euler-Lagrange equations of motion for a discretized Cosserat curve is implemented in its entirety. Solutions to the dynamics equations are derived and a framework for symbolic integration is outlined. The resulting system is not unconditionally positive definite but requires balanced physical parameters in order to be solvable using a regular linear solver. Several implementation examples are presented, as well as a novel modeling technique based on non-linear optimization.
159

Population patterns of hair zinc, dietary and socio-demographic determinants

Vaghri, Ziba 05 1900 (has links)
Marginal zinc deficiency (MZD) exists in children of industrialized societies and can impair growth and development. Presently there are no data available on its global prevalence. It is believed that MZD is one of the most common hidden deficiencies throughout the world. This is partly because of the lack of sensitivity and specificity of serum zinc, the most commonly used biomarker of zinc status, to detect MZD . This deficiency in children is always accompanied by a decrease in hair zinc . Although in research settings hair zinc is a recognized biomarker of MZD in children, health practitioners do not presently use it. These cross-sectional studies were designed to examine the hair zinc status of preschoolers in Vancouver . They also aimed at exploring some dietary and non-dietary factors associated with hair zinc status in an attempt to construct and validate a screening tool for detection of MZD. Our first study indicated a mean hair zinc of 75±30 μg/g, with 46% below the cutoff (<70μg/g) for a group (n=87) of low-income preschoolers (Chapter II). Among these children we observed negative associations between the hair zinc and consumption of dairy (R² =0.09, P=0 .01) and milk (R² =0.08, P=0.01), being described as "often sick" (R² =0.55, P=0 .00) and "eating unhealthy" (R² =0.16 P=0.00), and prolonged breastfeeding (R² =0.11, P=0.01). Our citywide survey (n=719) indicated a mean hair zinc of 116±43 μg/g with 17% below the cutoff (Chapter III). Logistic regression analysis indicated sex, age, maternal education, the number of adults at home, consumption frequency of milk, "scores of activity level", "being described as frequently sick" and "taking supplements containing iron" as the significant predictors of hair zinc status . However, the final model had 16% sensitivity while having 98 .3% specificity, indicating its lack of usefulness as a screening tool. Our study provides important information on the hair zinc status of Vancouver preschoolers. Although we did not accomplish our primary goal of constructing and validating a screening tool, we did identify some factors in children and their environment associated with hair zinc, which may help in better understanding of hair zinc as a biomarker of MZD . / Land and Food Systems, Faculty of / Graduate
160

Quantitatively Assessing the Genetics of Hair Color in Addition to Identifying Regulatory Elements Impacting Body-Mass Index in the FTO Gene

Hopkins, Racquel 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Obesity is a medical condition whose rates have seen a rise in both the United States and worldwide in recent decades. Numerous studies have been done to understand obesity, and through the use of GWAS researchers have been able to find multiple genetic factors that can contribute to obesity in mammals. One proposed cause of obesity are genetic impacts on cilia formation in the CNS, which causes downstream effects on food intake and energy expenditure, causing obesity via overeating and decreased activity. In the first half of this thesis, I describe a study, in collaboration with the Berbari Lab at IUPUI, that explored the human chromosome 16:53801550-53808600 (GRCh37/hg19), an intron of the FTO alpha-ketoglutarate Dependent Dioxygenase (FTO) gene for transcriptional regulators that impact BMI and obesity. First, using control DNA, PCR, and gel-electrophoresis, we created an assay for 44 primer sets (forward and reverse) covering the genomic region. After optimizing the assay, we then selected 111 human DNA samples across three weight groups (underweight, normal weight, and obese) to sequence using the assay. The samples were selected from subjects enrolled in the Walsh Lab FDP study. Sequencing was completed using the Illumina MiSeq System, and sequenced results were viewed using the Integrative Genomics Viewer (IGV) program. Variants that showed in the results were analyzed across and within the weight groups, and their locations were researched for previously known BMI or enhancer activity using online genome browsers Ensembl and UCSC Genome Browser. The results of this study revealed two SNPs, rs8055197 and rs11642015, that provided the best correlation with the weight categories among the samples. These results were consistent with literature that previously linked these single-nucleotide polymorphisms (SNPs) to obesity, particularly in relation to genes that are regulated by FTO (CUX1, POMC, and IRX3/5). Both SNPs lie within areas that show high enhancer activity in neural crest cells, important cells for cilia formation. Although there were SNPs in high LD within both regions, these two SNPs were chosen due to their homologous variant locations within the mouse genome (rs8055197 - GRCm38/mm10 8:91376305; rs11642015 - GRCm38/mm10 8:91375651), which provides a means of testing this obesity correlation, with a proposed enhancer relationship through FTO, in mouse models. In the second half of this thesis, I explored new methods for quantitatively defining natural hair color categories, and attempted to find novel SNPs impacting hair color in a GWAS using the quantitative values as phenotypes. In previous publications, the development and validation of the HIrisPlex-S Prediction Tool for hair prediction was made using categorical hair colors, which were defined and classified by individual researchers or lab personnel. Using spectrophotometer measurements and HSV color values, we used a machine-learning tool to objectively classify sample hair photos into natural hair color classes. We then used this quantitative data as the input phenotype for a GWAS, using both linear regression and linear mixed model regression, to search for new genetic associations with these objectively defined hair color classes. Lastly, we also measured correlations between these hair color phenotypes and a SNP array consisting of all currently known pigment SNPs cited in recent literature. The results of this study showed that quantitative values can be used as a means of classifying human hair colors. Both models used in the GWAS highlighted previously known SNPs that contributed to quantitative hair color. By utilizing the linear mixed model approach which has the ability to generate more power due to the normalization of hidden population structure, there was one near genome-wide significant SNP found that is currently not linked with hair color, rs2037697 (IQUB), which showed strong associations with light brown hair (p-value = 1.83192E-07), however this would need to be confirmed with increased numbers to validate its association. The results of the correlation analysis showed that SNPs cited as having impacts on pigmentation (eye, skin, and hair) also show strong associations with these objectively defined quantitative hair color classes and these rankings may prove very useful as the field moves towards quantitative hair color prediction.

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