The hilltop archaeological site, Bosutswe in Botswana had a nearly a thousand years of continuous occupation. Nearly every single strata in both precincts produced shell beads of various materials and origin. By using travelogue sources as well as more recent enthnographical sources, I focus on the possible uses and importance of beads to the people of Bosutswe and the wider southern African region. Using the excavated beads as evidence, I show how certain varieties of beads made their way to the site by way of trade routes with distant riverine areas. Also, I compare my findings with arguments claiming that different groups preferred different sizes beads; therefore, one can determine a site’s ethnic makeup by this measurement alone. / text

Controlled release formulations deliver an active ingredient over an extended period of time. It is an ideal dosage form for an active ingredient with a short elimination half-life. An active ingredient with a short elimination half-life would be released in small portions over an extended period of time and thus less frequent administration is necessary and this improve patient compliance. Other advantages of these formulations include: decreased side effects, constant drug levels in the blood, improvement in treatment efficiency and reduction in cost of administration. Controlled release beads are formulated in such a way that the active ingredient is embedded in a matrix of insoluble substance like chitosan; the dissolving drug then has to find its way through the pores of the matrix into the surrounding medium. The chitosan matrix swells to form a gel, the drug then has to first dissolve in the matrix and diffuse through the outer surface into the surrounding medium. Chitosan is a biocompatible, biodegradable polymer of natural origin. It has mucoadhesive properties as well as the ability to manipulate the tight junctions in the epithelium membrane and these properties have qualified chitosan as an effective drug carrier in controlled release dosage forms. The effect of a modern controlled release polymer namely Kollidon® SR in combination with chitosan on drug release was investigated. Ketoprofen was chosen as model drug. Ketoprofen is an anti-inflammatory drug that causes gastrointestinal side effects in conventional dosage forms. Ketoprofen has a short elimination half-life of 2.05 ± 0.58 h and this characteristic makes it an ideal candidate for use in a controlled release formulation. The aim of this study was to achieve controlled release and minimize gastrointestinal effects of ketoprofen with chitosan particles. Kollidon® SR was used as polymer because it exhibits pH independent release characteristics and previous studies have shown potential for this combination. Chitosan beads and chitosan-Kollidon® SR beads, as well as chitosan granules and chitosan-Kollidon® SR granules, were prepared and investigated as potential controlled release formulations. Chitosan beads were prepared through the inotropic gelation method using tripolyphosphate as a cross linking agent. Granules were prepared through wet granulation using 2% v/v acetic acid as the granulating fluid or by dissolving ketoprofen in ethanol and Kollidon® SR in 2-pyrrolidinone and using the solution as granulating fluid. Kollidon® SR was added in concentrations of 0.25, 0.5 and 1% (w/v) in the bead formulations and concentrations of 1, 5 and 10% (w/w) in the granule formulations. The beads and granules were characterised by evaluating the following properties: morphology, drug loading and drug release. Additionally swelling and friability tests were also conducted on the bead formulations. The cross linking times of the bead formulations were varied to investigate the effect of cross linking time on the characteristics of the beads. Chitosan-Kollidon® SR beads showed promising results for controlled release formulations and ketoprofen were released over an extended period of time. Drug loading of the plain chitosan beads was 74.65 ± 0.71% and it was noted that the inclusion of Kollidon® SR in the beads resulted in an increase in drug loading and the formulation containing 1% (w/v) Kollidon® SR, cross linked for 30 minutes had a drug loading of 77.38 ± 0.01%. Drug loading of the beads that were cross linked for a longer time were slightly lower which is an indication that some of the drug might have leached out during cross linking. The degree of swelling was promising with some beads swelling to a degree of 2.5 in phosphate buffer solution pH 5.6. Granules had a drug loading between 81.73 ± 1.53% and 93.30 ± 0.50%. Ketoprofen release from the beads and the granules in PBS pH 7.40 at 37 °C over a period of 6 hours were investigated. The bead formulations were more effective in achieving controlled release and it was noted that the bead formulations that was cross linked for a longer period was more efficient in achieving controlled release. The granules did not form a matrix and were not effective in achieving controlled release. Controlled release of ketoprofen were achieved and the results show potential for chitosan-Kollidon® SR formulations in the future. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.

Bovine reproductive performance is one of the most important factors influencing dairy farm profitability. Present-day techniques for oestrus- and pregnancy-detection are unreliable and labour-intensive. Although measuring milk-progesterone at regular intervals allows the fertility status of a cow to be determined reliably, the labour cost of collecting and analysing samples is prohibitive. This project aimed to develop a progesterone sensing system that could be automated and integrated with the milking unit, thus minimising labour costs. The proposed system involved mixing the milk sample with an enzyme-antibody conjugate and then passing the sample through a column containing immobilised progesterone. Any progesterone in the milk would inhibit conjugate binding to the column. An enzyme substrate would then flow through the column and bound conjugate would be detected as a colour change at the column's outlet. Periodate-coupling was used to attach horseradish peroxidase enzyme to anti-progesterone antibody, and progesterone-3-carboxymethyloxime was immobilised on the polystyrene bead surface using amine-coupling. Both techniques are widely used. Initial experiments attempted to verify the success of these two reactions simultaneously, whereas later experiments focused on the bead-coating. Beads were suspended in a specially-constructed syringe and the antibody activity of the eluted solution was measured by SPR. However, a combination of non-specific binding and antibody stability and activity issues meant neither reaction was conclusively verified. Many trials were done to investigate how to overcome the problems encountered but a suitable, workable procedure was not developed. Despite poor progress, the problems encountered did not undermine the project's potential. There remains optimism of developing an on-line method if research were to continue.

Imagine if you could combine the power and capabilities ofan entire laboratory in the palm of your hand. Advances inmicrofluidic chip technology promise to integrate andminiaturize multiple lab processes into a single palm-sizeddevice. The advantages of these lab-on-a-chip devices,sometimes also referred to as micro total analysis systems(µTAS), compared with conventional bench-scale systems arenumerous and wide ranging and include: less reagentconsumption, low manufacturing costs, increased performance,faster analysis, high sample throughput, integration andautomation possibilities, and disposability. However,microfluidic devices also present challenges such as theinterfacing to the macro world and detection limits. In this thesis the focus has been to develop novel discretemicrofluidic components for biotechnology and organic chemicalapplications with the goal to integrate them to formlab-on-chips. A flow-through filter-chamber device has beendesigned, manufactured and evaluated for chemical analysis onbeads. Passive liquid handling has been integrated on the chipin the form of hydrophobic valves at the inlet channels. Anarray format has also been developed to allow parallel analysisof multiple samples. The filter-chamber functions well forsingle nucleotide analysis using pyrosequencing. Initialevaluations on catalyst screening in the filter-chamber devicehas been performed. The suitability of valve-less micropumps for biochemicalapplications is presented. Fluids encountered in variousbiochemical methods, including living cells, that areproblematic for other micropumps have been pumped with goodperformance. This thesis also introduces expandablemicrospheres as a novel component in microfluidics includingapplications such as one-shot valves, micropositioning andsurface enlargement. A novel technique for bead immobilization in microfluidicdevices based on surface chemistry is presented in this thesis.Beads for both biochemical assays and organic chemistry havebeen self-sorted and self-assembled in line patterns as narrowas 5 µm on both structured and unstructured substrates.This method will greatly facilitate the generation of screeningplatforms, for example. To develop a microfluidic device for catalysis-on-chip,ligands for asymmetric catalysis have successfully beenimmobilized in silicon channels by consecutive microcontactprinting, which is a novel technique presented in thisthesis. <b>Keywords:</b>microfluidics, beads, microspheres, silicon,filter-chamber, flow-through, bead trapping, DRIE, passivevalves, fluorocarbon, microfluidic array, adhesive bonding,valve-less micropump, microcontact printing, PDMS,self-assembly, self-sorting, DNA, SNP, pyrosequencing,allele-specific extension, expandable microspheres, catalysis,chiral ligand, monolayer, miniaturization, lab-on-a-chip,µTAS.

<p>Imagine if you could combine the power and capabilities ofan entire laboratory in the palm of your hand. Advances inmicrofluidic chip technology promise to integrate andminiaturize multiple lab processes into a single palm-sizeddevice. The advantages of these lab-on-a-chip devices,sometimes also referred to as micro total analysis systems(µTAS), compared with conventional bench-scale systems arenumerous and wide ranging and include: less reagentconsumption, low manufacturing costs, increased performance,faster analysis, high sample throughput, integration andautomation possibilities, and disposability. However,microfluidic devices also present challenges such as theinterfacing to the macro world and detection limits.</p><p>In this thesis the focus has been to develop novel discretemicrofluidic components for biotechnology and organic chemicalapplications with the goal to integrate them to formlab-on-chips. A flow-through filter-chamber device has beendesigned, manufactured and evaluated for chemical analysis onbeads. Passive liquid handling has been integrated on the chipin the form of hydrophobic valves at the inlet channels. Anarray format has also been developed to allow parallel analysisof multiple samples. The filter-chamber functions well forsingle nucleotide analysis using pyrosequencing. Initialevaluations on catalyst screening in the filter-chamber devicehas been performed.</p><p>The suitability of valve-less micropumps for biochemicalapplications is presented. Fluids encountered in variousbiochemical methods, including living cells, that areproblematic for other micropumps have been pumped with goodperformance. This thesis also introduces expandablemicrospheres as a novel component in microfluidics includingapplications such as one-shot valves, micropositioning andsurface enlargement.</p><p>A novel technique for bead immobilization in microfluidicdevices based on surface chemistry is presented in this thesis.Beads for both biochemical assays and organic chemistry havebeen self-sorted and self-assembled in line patterns as narrowas 5 µm on both structured and unstructured substrates.This method will greatly facilitate the generation of screeningplatforms, for example.</p><p>To develop a microfluidic device for catalysis-on-chip,ligands for asymmetric catalysis have successfully beenimmobilized in silicon channels by consecutive microcontactprinting, which is a novel technique presented in thisthesis.</p><p><b>Keywords:</b>microfluidics, beads, microspheres, silicon,filter-chamber, flow-through, bead trapping, DRIE, passivevalves, fluorocarbon, microfluidic array, adhesive bonding,valve-less micropump, microcontact printing, PDMS,self-assembly, self-sorting, DNA, SNP, pyrosequencing,allele-specific extension, expandable microspheres, catalysis,chiral ligand, monolayer, miniaturization, lab-on-a-chip,µTAS.</p>

Thesis (M.A.)--University of West Florida, 2009. / Submitted to the Dept. of Anthropology. Title from title page of source document. Document formatted into pages; contains 250 pages. Includes bibliographical references.

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The amber spacers from Bronze Age Britain and Europe are one of the most well known artefact groups from this time period. Yet despite the frequency with which these artefacts are cited, the details of these finds both individually and within their original excavation contexts appear to be poorly understood. Recent new finds of ‘sets’ of spacers prompted this review and updating of the amber spacer corpus, which now extends to 375 individual spacers from 141 findspots. Once thought to constitute an artefact horizon which could provide a chronological bridge between the regions of Northwest Europe and Britain / the Central European Únĕtice/Tumulus Cultures and Late Helladic I and II Mycenaean Greece, new radiocarbon dating programs have extended their date range from (potentially) c. 2000 cal B.C. to c.1360 cal. B.C., although the regional chronologies remain essentially unresolved. To give a clear survey of how the spacers have been viewed historically, the catalogue entry for each findspot/spacer includes, as well as information about the findspots themselves, x-rays, photographs and drawings produced for this research, alongside all the previously published quotes and illustrations. Microscopic analyses provide evidence for some spacer-sets having been fragmented and deposited separately. Maps showing illustrations of the spacers where they were recovered allow comparison of regional similarities and differences. Loose colour plates show the x-rays of groups of spacers which have been correlated in past interpretations at 1:1 scale for easy comparison. Some earlier interpretations, including the Crescentic/Pendant regional division, the jet spacer/amber spacer/lunulae discrete distribution pattern and the close relationship of the Basic Pattern spacers, are challenged and found to no longer be sustainable. The craft and production aspects of spacer manufacture, particularly the procurement of suitable raw material, are addressed and a new narrative is presented, which is partly informed by the experimental replica research.

Controlled release formulations deliver an active ingredient over an extended period of time. It is an ideal dosage form for an active ingredient with a short elimination half-life. An active ingredient with a short elimination half-life would be released in small portions over an extended period of time and thus less frequent administration is necessary and this improve patient compliance. Other advantages of these formulations include: decreased side effects, constant drug levels in the blood, improvement in treatment efficiency and reduction in cost of administration. Controlled release beads are formulated in such a way that the active ingredient is embedded in a matrix of insoluble substance like chitosan; the dissolving drug then has to find its way through the pores of the matrix into the surrounding medium. The chitosan matrix swells to form a gel, the drug then has to first dissolve in the matrix and diffuse through the outer surface into the surrounding medium. Chitosan is a biocompatible, biodegradable polymer of natural origin. It has mucoadhesive properties as well as the ability to manipulate the tight junctions in the epithelium membrane and these properties have qualified chitosan as an effective drug carrier in controlled release dosage forms. The effect of a modern controlled release polymer namely Kollidon® SR in combination with chitosan on drug release was investigated. Ketoprofen was chosen as model drug. Ketoprofen is an anti-inflammatory drug that causes gastrointestinal side effects in conventional dosage forms. Ketoprofen has a short elimination half-life of 2.05 ± 0.58 h and this characteristic makes it an ideal candidate for use in a controlled release formulation. The aim of this study was to achieve controlled release and minimize gastrointestinal effects of ketoprofen with chitosan particles. Kollidon® SR was used as polymer because it exhibits pH independent release characteristics and previous studies have shown potential for this combination. Chitosan beads and chitosan-Kollidon® SR beads, as well as chitosan granules and chitosan-Kollidon® SR granules, were prepared and investigated as potential controlled release formulations. Chitosan beads were prepared through the inotropic gelation method using tripolyphosphate as a cross linking agent. Granules were prepared through wet granulation using 2% v/v acetic acid as the granulating fluid or by dissolving ketoprofen in ethanol and Kollidon® SR in 2-pyrrolidinone and using the solution as granulating fluid. Kollidon® SR was added in concentrations of 0.25, 0.5 and 1% (w/v) in the bead formulations and concentrations of 1, 5 and 10% (w/w) in the granule formulations. The beads and granules were characterised by evaluating the following properties: morphology, drug loading and drug release. Additionally swelling and friability tests were also conducted on the bead formulations. The cross linking times of the bead formulations were varied to investigate the effect of cross linking time on the characteristics of the beads. Chitosan-Kollidon® SR beads showed promising results for controlled release formulations and ketoprofen were released over an extended period of time. Drug loading of the plain chitosan beads was 74.65 ± 0.71% and it was noted that the inclusion of Kollidon® SR in the beads resulted in an increase in drug loading and the formulation containing 1% (w/v) Kollidon® SR, cross linked for 30 minutes had a drug loading of 77.38 ± 0.01%. Drug loading of the beads that were cross linked for a longer time were slightly lower which is an indication that some of the drug might have leached out during cross linking. The degree of swelling was promising with some beads swelling to a degree of 2.5 in phosphate buffer solution pH 5.6. Granules had a drug loading between 81.73 ± 1.53% and 93.30 ± 0.50%. Ketoprofen release from the beads and the granules in PBS pH 7.40 at 37 °C over a period of 6 hours were investigated. The bead formulations were more effective in achieving controlled release and it was noted that the bead formulations that was cross linked for a longer period was more efficient in achieving controlled release. The granules did not form a matrix and were not effective in achieving controlled release. Controlled release of ketoprofen were achieved and the results show potential for chitosan-Kollidon® SR formulations in the future. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.

This study is aimed to compare the fluidized bed and microwave drying with microwave assisted fluidized bed drying. For this purpose, macaroni beads (2.4&plusmn / 0.08 mm diameter) were dried from about 20% to 12% moisture content in a fluidized bed of 7.6 cm diameter, in a domestic microwave oven with a power of 609 W and in the fluidized bed placed in the microwave oven conditions. In the experiments with the fluidized bed three air temperatures / 50, 60 and 70&deg / C at an air velocity of 2.3 m/s and in those with the microwave oven two power levels / 50% and 100% were used. The drying curves indicated that the drying rate increased with the air temperature and microwave power in each drying method. Microwave assisted fluidized bed drying reduced the drying time by about 50% and 11% on the average compared with the fluidized bed and microwave drying, respectively. Therefore, it was concluded that the drying time was reduced more by the effect of microwave energy than the fluidization. The effective diffusivities in the fluidized bed and microwave assisted fluidized bed drying were found to be in the order of 4.125x10-11 and 8.772x10-11 m2/s on the average, respectively. The effective diffusivities for the fluidized bed drying were fitted to an Arrhenius type of equation and the magnitude of the activation energy was found to be in the order of 12595 kJ/kg mol.