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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.
1

Faience and glass beads from the late Bronze Age shipwreck at Uluburun

Ingram, Rebecca Suzanne 29 August 2005 (has links)
Beads are one of the earliest forms of ornamentation created by humans; prized during the Bronze Age for both their aesthetic as well as amuletic value, beads also served to signify the social status of the wearer. Beads functioned as an important trade commodity during the Late Bronze Age, as demonstrated by their abundance aboard the Uluburun shipwreck. This Late Bronze Age shipwreck, discovered off the Turkish coast at Uluburun in 1982, dates to approximately 1300 B.C. Thousands of beads of vitreous material were found on the shipwreck, including approximately 75,000 faience beads and 9,500 glass beads. Bead form and style represented in the faience and glass beads at Uluburun are relatively simple and are quite common at archaeological sites throughout the Late Bronze Age Levant. Faience beads found at Uluburun vary widely in form and comprise eight distinct categories. While the surface glaze remains in rare patches only, most faience beads exhibit a blue undertone. Other colors, while less common, include red, yellow, white and turquoise. The glass beads found at Uluburun may be loosely grouped into two categories, small and large. Many of the large glass beads exhibit yellow and white spot or crumb decoration, or a combination of both, and there is a distinctpossibility that all the large glass beads were decorated in this way, but surface deterioration masks the decoration. Many of the faience and glass bead categories represent items of cargo, as evidenced by a concreted lump of small glass beads transported inside a Canaanite jar. Other, less prolific, bead categories probably represent the personal belongings of the crew or passengers aboard the ship. Beads found in archaeological contexts are notoriously difficult to date due to their extended use throughout generations; for this reason, the Uluburun beads represent an important contribution to the archaeological record and bead studies in particular, for the mere fact that they may be dated by provenance alone to the late 14th century B.C.
2

19th century glass trade beads : from two Zulu royal residences

Saitowitz, Sharma Jeanette 07 March 2017 (has links)
No description available.
3

Beadwork: its cultural and linguistic significance among the South African Ndebele people

Mashiyane, Zwelabo Jacob January 2006 (has links)
Submitted in fulfilment of the requirements for the Doctor of Philosophy in the Department of Isizulu naMagugu at the University of Zululand, 2006. / This study is an attempt at making a classiflcatory scrutiny of the art performed by the Ndebele people of South Africa. It sets out to identify and define Ndebele beadwork by looking very closely to its origin, how it survived the dark days of waging wars and made its way into the modern times. In its classification a clear distinction is drawn between the various periods of development and the characteristics of each period are described well. Several attempts have already been made by a number of scholars on the classification and analyses of Ndebele beadwork. In most analyses we find that very brought and general descriptions have been given. One hardly finds any definite patterns and methods used by a Ndebele bead worker. This study has attempted to describe Ndebele beadwork from the moment of planning to the next step when the first grain of bead is worked through the needle and cotton up to where a real shape is formed. It attempts to explain how the intricate Ndebele shapes are formed and coordinated. The use of the various colours is explained in detail. The wrong impression conceived by a big bulk of people that the Ndebele people use colours indiscriminately is corrected. An explanation is given on how some of the popular colours are linked to speech and how these colours are generally interpreted when used on a piece of beadwork article. It further rounds up the typical shapes popular with the Ndebele bead worker. It describes how each shape is formed and used. It also discusses the cultural beliefs and stereotypes attached to the usage of beads and the restrictions accompanying them. The future of Ndebele beadwork is looked into. Recommendations on how the beadwork trade can be turned into a giant industry are made. Postulatxons are made on what route can be followed that can lead small beadwork handlers into some of the world's greatest.
4

Die Spur der Glasperlen Akteure, Strukturen und Wandel im europäisch-ostafrikanischen Handel mit Glasperlen /

Vierke, Ulf. January 1900 (has links) (PDF)
Thesis (doctoral)--Universität Bayreuth, 2004. / Title from title screen (viewed June 10, 2009). Includes bibliographical references (p. 529-541).
5

Evaluation of in vitro serial antibiotic elution from meropenem-impregnated polymethylmethacrylate beads after ethylene oxide gas and autoclave sterilization

Baez, Leonardo Alfredo 07 August 2010 (has links)
The objective of this study was to determine elution properties of meropenem and compare the elutions of meropenem impregnated PMMA beads without sterilization (PMMA-Cont) to those sterilized with steam (PMMA-Auto) and ethylene oxide gas (PMMA-EO). Four groups of beads were produced: one group without antibiotic and three groups of meropenem impregnated beads: PMMA-Cont, PMMA-Auto, and PMMA-EO. Antibiotic concentrations in eluent samples were determined using a microbiological assay at different time intervals. The microbiological assay resulted in no zone of inhibition at all time periods for the PMMA-Auto samples and the samples of PMMA without antimicrobial. The meropenem concentration on the eluent remained above 4 mcg/ml for 15 days in the PMMA-Cont group and until day 18 for PMMA-EO group. The meropenem incorporated in the PMMA beads elutes effectively and gradually decreases after the 24 hour peak. Ethylene oxide does not adversely affect meropenem’s elution.
6

GLASS BEADS AND PRE-EUROPEAN TRADE IN THE SHASHE-LIMPOPO REGION

Wood, Marilee Hopkins 23 March 2006 (has links)
Master of Arts - Arts / During the Islamic period (8th to 15th centuries) glass beads are the most abundant evidence of international trade in southern Africa. Archaeologists, however, have underutilized them because they are small, monochrome and difficult to categorize. I show they can be divided into identifiable series that have temporal parameters. Once identified, the beads can help interpret site chronology as well as regional and international interaction. Glass beads are also useful in reconstructing trade patterns in the Indian Ocean. Present perceptions concerning Islamic period trade to eastern and southern Africa are based largely on Islamic ceramics and Arab documents. Thus, it is generally believed that trade to southern Africa was an extension of the East Coast monsoon-driven trade that was conducted mainly by local mariners familiar with the difficult conditions in the Mozambique Channel. Comparison of glass bead assemblages from eastern and southern Africa, however, shows that it is unlikely the beads reaching the south were traded through ports to the north. Based on distribution patterns and recent chemical analyses, I propose they were arriving directly from South and/or Southeast Asia.
7

Filmes e beads à base de quitosana: incorporação de compostos luminescentes e estudos de interações hospedeiro-hóspede

ANJOS, Fernanda Santos Carvalho dos January 2005 (has links)
Made available in DSpace on 2014-06-12T23:02:01Z (GMT). No. of bitstreams: 2 arquivo9212_1.pdf: 9706142 bytes, checksum: 8eabcae0dc12dd2c5311a17d02a7a025 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2005 / A quitosana é um polissacarídeo obtido, geralmente, a partir da hidrólise da quitina, em meio alcalino, por meio de reação de desacetilação em temperaturas elevadas sob condições heterogêneas. As propriedades da quitosana e, conseqüentemente, suas aplicações dependem do seu grau de desacetilação e da sua massa molar média. Assim a primeira parte deste trabalho consistiu na caracterização de três quitosanas utilizadas nesse trabalho, por espectroscopia no infravermelho, RMN 1H, RMN 13C e medidas viscosimétricas. O grau de desacetilação das quitosanas ficou entre 68% e 78% e a massa molar entre 2,75 x 105 e 3,34 x 105 g.mol-1. As análises de difração de raios-X mostraram que os índices de cristalinidade de todas as quitosanas purificadas foram maiores do que as quitosanas não purificadas devido à reorganização das cadeias durante o processo de aquecimento. Na segunda parte do trabalho, foram preparados filmes e beads de quitosana. Os filmes foram obtidos a partir de soluções de quitosana, que foram depositados em uma superfície plana de poliestireno para a evaporação do solvente. Após secagem os filmes formados foram removidos por destacamento. Os beads foram obtidos a partir do gotejamento de soluções de quitosana em solução de trifosfato de sódio. Estes são imediatamente formados, resultando de interações de caráter eletrostático entre o policátion de quitosana e o ânion trifosfato, P3O10 5-, conservando a forma e tamanho da gota. Os filmes e beads foram caracterizados por difração de raios-X e microscopia eletrônica de varredura. O índice de cristalinidade dos filmes diminuiu em relação à quitosana indicando uma baixa organização das cadeias na formação dos mesmos. Em seguida, foram incorporados compostos orgânicos luminescentes (harmana, fluoresceína e rodamina B) nos filmes e beads à base de quitosana e, então, caracterizados por espectroscopia de absorção na região do UV-visível e espectroscopia de emissão. Todos os espectros de absorção e emissão dos luminóforos mudaram com a incorporação aos filmes de quitosana. Os espectros de absorção mostraram um deslocamento do equilíbrio das espécies neutras e catiônicas da harmana para sua forma neutra com a formação dos filmes, indicando que o filme de quitosana tem caráter básico, o que foi confirmado pelo espectro de emissão. Nos filmes com fluoresceína foi observado que houve um deslocamento das bandas de absorção, indicando a formação de espécies dianiônicas, o que sugere a sua adsorção à quitosana. Já no filme com rodamina B foi observado um aumento na concentração de dímeros após a formação dos filmes A cinética de liberação da rodamina B dos filmes e beads em PBS e água foi também estudada. A rodamina liberada foi medida por espectroscopia. Foram utilizados dois modelos: Higuchi e Koorsmeyer Peppas. Observou-se que a liberação a partir de filmes e beads em água ocorre por difusão Fickiana e que somente a liberação a partir de beads em PBS ocorre por difusão não-Fickiana. Em todas as amostras estudadas, exceto a liberação do corante dos beads de quitosana em PBS, foi observado a difusão Fickiana
8

Elution of Metronidazole and Gentamicin from Polymethylmethacrylate Beads

Ramos, Jose Rafaelix 16 June 2003 (has links)
Ten polymethylmethacrylate (PMMA) beads containing metronidazole (3 concentrations); gentamicin sulfate; or metronidazole and gentamicin sulfate were immersed in 5 ml of phosphate buffered saline in triplicate. Eluent was replaced at specified time intervals for 1 day (1, 3, 6, 12 and 24 hours), daily, or weekly for 21 days. Antibiotic concentrations were measured by high performance liquid chromatography. Changes in antibiotic bioactivity attributable to polymerization or co-polymerization of the antibiotics with PMMA, ethylene oxide sterilization, and storage of antibiotic-impregnated PMMA (AIPMMA) beads containing metronidazole were evaluated. Antibiotic elution patterns were similar for all groups. Day-1 elution for groups containing either metronidazole (3 concentrations) or gentamicin represented a mean 63% to 66% and 79% respectively of the 21-day total elution. Approximately 50% of the day-1 elution occurred during the first hour. The elution of metronidazole was dose-dependent. There was no significant difference in the total amount of antibiotic eluted from groups that had the saline changed daily versus weekly. The elution of metronidazole (day 3-21) and gentamicin (all days) was significantly greater when metronidazole and gentamicin were combined (p<0.05). Polymerization of PMMA was delayed in groups containing metronidazole. Neither polymerization nor co-polymerization of metronidazole and gentamicin with PMMA, gas-sterilization, or 2-month storage of beads containing metronidazole significantly affected antimicrobial bioactivity. Metronidazole elutes from PMMA. The frequency at which the saline was changed did not affect the rate of antibiotic elution. Co-polymerization of metronidazole and gentamicin sulfate in PMMA resulted in increased rates of elution. Intra-operative preparation of metronidazole-impregnated PMMA beads is not practical. However, prefabrication of metronidazole or metronidazole-gentamicin beads, gas-sterilization and storage for up to 2 months should not affect the efficacy of either antibiotic. The local delivery of biologically active metronidazole and gentamicin by elution from PMMA is feasible. / Master of Science
9

DEVELOPMENT OF IMMUNOMAGNETIC BEAD ASSAY WITH ELECTROCHEMICAL DETECTION FOR USE IN A MINIATURIZED SENSOR

Purushothama, Shobha 11 October 2001 (has links)
No description available.
10

Expanze velkoobchodu bižuterií a korálků na pozadí hospodářské krize / Expansion of wholesale costume jewelry and beads under the economic crisis

Odvárka, Jan January 2010 (has links)
The aim of this work is to answer the question, whether it is possible to run a successful business with czech costume jewelry and beads under the current economic crisis situation and under changes that business with costume jewelry and beads in general is facing. The paper analyzes international trade with costume jewelry and beads. It also analyzes current position of the Czech Republic on the market and finds reasons, which cause current unfavourable situation of the jewelry industry in the Czech Republic. Based on the findings, it proposes business strategy, which should be used by businesses with Czech costume jewelry and beads in order to achieve business growth. This strategy is then tested under real market conditions.

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