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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.
21

The roles of Sox2 and Sox18 in hair type specification and pigmentation

Chan, N. S., Michelle., 陳雁璇. January 2007 (has links)
published_or_final_version / abstract / Biochemistry / Master / Master of Philosophy
22

Chemical and morphological properties of scalp hair in normal and abnormal states

Rushton, D. H. January 1988 (has links)
No description available.
23

Circadian rhythms in hair follicle cells

Dawn, Gary T. 03 June 2011 (has links)
Circadian mitotic rhythms in epithelial cells of human epidermis (Schevirg, 1959), rat cornea (Scheving,1967) and intestinal epithelium of the mouse (Sidgestad,1972) have been reported in the literature. It is the attempt of this investigation to determine the presence of a circadian rhythm governing the mitotic activity of hair follicle cells in neonatal white mice. The animals used were reared under closely controlled conditions of temperature, humidity, lighting and food. A total of forty-eight, three to four day old mice were used, with eight animals being sampled every four hours over a twenty-four hour period. Skin sections were removed and fixed in Bouins fluid. The tissues were dehydrated in alcohols, cleared in xylol and infiltrated and embedded in paraffin. The sectioned tissues were placed on glass slides, rehydrated and stained with hematoxylin and eosin. To assess the mitotic activity over the twenty-four hour period, cell counts within the follicles were made from the slides. For each animal, 1000 hair follicle cells were counted. Cells undergoing mitosis were identified and specific stages were tallied. These stages were 1) prophase, 2) metaphase, 3) anaphase-telophase and 4) unidentifiable cells. Photomicrographs were made to record the histology and demonstrate the mitotic activity.When the data was statistically analyzed, an analysis of variance test failed to show a significant difference among the mean values of dividing cells from animals sampled during the different time periods. However, the F value for metaphase favorably approaches the table F value for the conditions of this study.By far, the strongest data to support the existence of a circadian rhythm within the hair follicle cells of mice is demonstrated when the mean values for each of the mitotic cell categories are plotted against time for the twenty-four hour period. Metaphase shows peaks in activity at 6:00 a.m. and 10:00 p.m. A similar pattern is also seen for the unidentifiable cells. The peak mitotic activities for prophase, and anaphase-telophase was seen to occur at 10:00 p.m.
24

Purification and analysis of the trichohyalin gene : an examination of the role of tricohyalin in the inner root sheath / Michael James Fietz.

Fietz, Michael J. January 1991 (has links)
Includes bibliographical references. / 1 v. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Biochemistry, 1991
25

Molecular and functional characterisation of a system ASC-like neutral amino acid transporter expressed in the wool follicle / Gregory Scott Nattrass.

Nattrass, Gregory Scott January 2000 (has links)
Bibliography : leaves 153-162. / xi, 162 leaves : ill. (chiefly col.) ; 30cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The objective of this project was to isolate follicle-derived cDNA clone(s) encoding putative L-cysteine transport proteins, and to determine their amino acid transport function in virto. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 2000
26

A new method for the analysis of human hair : a morphological case study of five sample populations

Weitzel, Misty A. 09 June 1998 (has links)
Hair is an important piece of evidence in forensic and archaeological investigations. Analysis of the morphological features of hair has been reported since at least the early 1800's. However, many questions still remain unanswered such as, how can human groups (or local populations) be analyzed and possibly distinguished from each other based on the morphology of their hair? This investigation successfully established a set of procedures for analysis of human hair morphology and explored the possibility of separating populations by examining a case study of 40 hairs from five sample populations (Mongolian, English, Vietnamese, Native American Sioux and Oneida). The methodology leads the investigator from the point of receiving a single hair to acquiring a list of specific, discernible traits characterizing that hair. These methods included a variety laboratory procedures (cleaning, casting, mounting and microtome sectioning of the hair) and examination procedures (microscope and computer imaging and developing a key and database). Statistical analysis was then utilized in order to determine the variability and/or relationships between the populations. Although the results were not statistically significant, they weakly support a division of three groups: English, Mongolian and Vietnamese, and Sioux and Oneida. The small sample size and overlap between the five populations is a limiting factor in attempting to discriminate between populations and should be taken into consideration in future investigations. / Graduation date: 1999
27

Hair today, gone tomorrow: the degradation and conservation of archaeological hair fibers

Sager, Rebecca M. 15 May 2009 (has links)
The research of this work describes the degradation and conservation of archaeological hair fibers. Chapter I will be a brief overview, with Chapter II following with a literary review and definition of terms. Chapter III focuses on research centered on the structure of hair fibers and their physical and chemical attributes. It will also focus on the archaeological and historical evidence of hair fiber use by humans. This research will help form the backbone of the paper and experiments performed. The next chapter focuses on the degradation of hair fibers in different environments. Hair fibers left in underwater, open air, burial, and arid environments are monitored for degree of degradation and brittleness. The hair fiber types used are four commonly found hair fibers types: coarse wool, fine wool, mohair, and human hair. After deposition, conservation using silicone oil treatment is tested on the degraded hair fibers. When silicone oil treatment proves to be a viable conservation method, the technique is then be applied to two artifacts. The two artifacts used are a Victorian era watch fob made from human hair and hair fibers mixed with tar from the excavation of Kittern in Bulgaria. Chapter VII deals with the conclusions of the experiments as a whole. The degradation of the fibers in different environmental conditions show that burial in acidic sandy clay is the most detrimental to hair fibers, while hair fibers from arid, dry environments are brittle, but well preserved aesthetically. The silicone oil treatments are shown to be viable treatment methods with positive results for all of the fibers tested, including two artifacts, a Victorian watch fob made from human hair fibers and hair fibers mixed with a tar-like substance from the shipwreck Kittern in Bulgaria.
28

A Study On Hair Regulations Systems For Junior High School Students

Huang, Shu- Ling 07 September 2006 (has links)
In regard to regulations restricting junior high school students on their attirement, hair style and appearances, the Ministry of Education (MOE) had announced in a letter dated January 20, 1987 with reference no. 02889 to abolish the ¡§Students¡¦ Hair length Standard¡¨. In addition, to operate in coordination with relevant rules and regulations that had continuouslly been amended and published, MOE had held numerous meetings to review reports from Bureaus of Education. MOE reiterated via news media and issued letters to Educational Administrative Agencies nation-wide that in accordance to Teachers¡¦ Act, schools should adopt and synthesize opinions from school administrators, teachers, parents, student representatives, and etc., to establish their own policy with regard to students¡¦ attirement, hair style and appearances. Starting from the academic year 2005, rights of students should be respected and stipulated in school disciplines. Schools that cite the abolished MOE regulations in current school disciplines and student handbooks should speed up in reviewing and amending the rules. In view of democracy and human rights concept, and to repect individual conscious of students, schools are requested not to restrict students to a certain type of hairstyle and punish students according to any standard. Instead, schools should respect individual choices, allow different opinions, and embrace diverse concepts toward beauty based on natural, neat and tidy premises. Furthermore, schools should focus their education on development of students¡¦ character and to enhance life and esthetics education, so as to strengthen and promote students¡¦ ability to self discipline and be independent. This research collects data from various surveys as well as coments and suggestions from scholars and experts before and after the hair regulation being abolished. The analysis is done vertically and horizontally from historical point of view and functional angle, assited with comparison among countries using similar hair regulation systems. It probes into Taiwan¡¦s hair regulation system to seek out and propose an ideal direction to fit in today¡¦s society of diverse value and to train up students with moral integrity and independent personality.
29

How insects stay clean

Amador, Guillermo Javier 08 June 2015 (has links)
This thesis considers a physical perspective to an insect's maintenance of a clean body surface.  Flying insects are faced with a barrage of particles in their environment, including dust, pollen, pollutants, and parasitic mites, the last of which are responsible for the modern decline of honey bees, of critical importance to agriculture around the world.  In this combined experimental, theoretical, and numerical study, we elucidate the mechanisms by which insects stay clean.  These mechanisms all rely on the insect’s coverage by a dense array of hairs.  We show that these bristles divert incoming flow, reducing deposition of particles, especially onto the eyes.  We replicate this mechanism with microfabricated pillar arrays, demonstrating the feasibility by which they may be incorporated into self-cleaning sensors. During grooming, the bristles on the limbs interact with those on the body and particle removal is achieved through combing and catapulting, driving particles at over 1000 gravities. We show that the three million hairs covering the body of a honey bee are crucial for the efficient removal of accumulated pollen.
30

Hair, art, and identity

Coleman, Christina Blair 22 August 2012 (has links)
The purpose of this report is to discuss the artwork I have produced over the past three years while in attendance at The University of Texas at Austin. My artwork consists of sculptures, drawings, and installations that investigate certain aspects of the politics of black hair as they relate to my identity as an African American woman. These aspects are intimacy, beauty standards, and empowerment. I use hair and hair care products as my materials with which to create. I specifically focus on hair care products which I used when I was a young girl including Blue Magic hair grease and barrettes, products which for many black women are associated with childhood. My aim is to create artwork that changes hair and hair care products from mundane grooming tools into valuable cultural artifacts. / text

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