The Internet is often touted as a panacea for perceived deficiencies in economic development. Its space-transcending abilities, which can instantly connect producers with consumers, have the potential to cut out intermediaries and to redistribute economic surplus in a more equitable manner. This dissertation asks whether the promises of the Internet are being realized in the Thai silk industry. The project explores the following questions: (a) At which nodes in the commodity chain is the Internet being used?; (b) How has the introduction of the Internet altered production chains and the flows of capital in the Thai silk industry?; (c) How are these changes altering the socio-economic conditions of actors who are involved in reconfigured production chains?; (d) What are the relationships between contemporary discourses about the economic benefits of disintermediated commodity chains and the actual effects of disintermediated commodity chains?; and (e) Are older local silk making traditions being replaced as producers interact with distant consumers through the Internet? This project uses a textual analysis of websites selling Thai silk to examine discourses being put forth about the effects of the Internet. Surveys and interviews with producers and merchants provide data on changes that the Internet is having on the production chains of Thai silk. Results suggest that in very few cases is the Internet allowing a disintermediation of commodity chains to occur. Internet users are actually more likely to position themselves as cybermediaries: buying from, and selling to other intermediaries. Although disintermediation is rarely occurring in the commodity chains of silk, the Internet is allowing firms to sell to a geographically diverse range of customers. These findings indicate that instead of placing buyers and sellers into copresence in a virtual marketplace, the Internet is rather being used as a tool to open up virtual conduits between those already occupying privileged economic positions in the commodity chains of Thai silk.

The silk fibres spun by insects and spiders have intrigued scientists for many years. Their mechanical performance is remarkable when one considers that the fibres are spun under ambient conditions from aqueous protein solutions without requiring many of the harsh processing conditions used in the production of man-made fibres. Yet, despite this interest, very little is known about the initial structure of the precursor proteins prior to spinning. One reason for this lies in the difficulty of handling the native proteins without accidental aggregation. Therefore in this thesis a novel sample preparation protocol for native silk is developed and small angle scattering (SAS) techniques are combined with circular dichroism (CD) and atomic force microscopy (AFM) to examine the structure and morphology of the proteins with different mechanical properties and thus biological function in nature. This work highlights the importance of studying native, functional proteins, at close to in vivo conditions, since clear differences in the structure and interaction of native and reconstituted silks can be attributed to the additional processing which reconstituted silks have undergone in order to be solubilised. Indeed native silk proteins are found to be more inherently non-interacting at quite high protein concentrations than reconstituted silk. Upon dilution, inter-chain interactions can be observed by SAS and CD as the protein is driven from its equilibrium conformation. This interaction and the shear-induced assembly of these proteins are also followed by AFM. Interestingly, native silk proteins from spider and silkworms retain a semiflexible conformation in solution. Indeed by comparing the silks from the major and minor ampullate, flagelliform and cylindriform glands of Nephila edulis with the cocoon silk of Bombyx mori silkworms, important insights are gained into how their flexibility suggests similarities in the local environment of the protein chains thereby dictating the hierarchical structure of silk fibres.

SiLK Tools is a suite of network ?ow tools that network analysts use to detect intru- sions, viruses, worms, and botnets, and to analyze network performance. One tool in SiLK is tuple ?ltering, where ?ows are ?ltered based on inclusion in a “multi-key” set (MKset) whose unique members are composite keys whose values are from multiple ?elds in a SiLK ?ow record. We propose and evaluate a more e?cient method of im- plementing MKset ?ltering that uses cuckoo hashes, which underlie McHugh et al.’s cuckoo bag (cubag) suite of MKset SiLK tools. Our solution improves execution time for ?ltering with an MKset of size k by a factor of O(logk), and decreases memory footprints for MKset ?ltering by 50%. The solution also saves 90% of disk space for MKset ?le storage, and adds functionality for transformations such as subnet masking on ?ow records during MKset ?ltering.

Cotton and wool have long dominated studies of the English textile industries, relegating silk manufacture to no more than a minor role in the British economy. Regional studies have likewise tended to concentrate upon areas dominated by a single feature or single industry. This thesis aims to address the economic and social impact of a silk industry established in the predominantly rural area of South West Hertfordshire. Here the indigenous population had other opportunities for employment, agricultural labour of various kinds forming the greatest occupational group. The straw plait absorbed female and child labour in the districts of Berkhamsted and St Albans, in direct competition to the silk mills, while the rag factories supplying the paper industry offered competition to the silk mills of Watford and Rickmansworth. Any industry dependent upon imports is especially vulnerable to external pressure, and an overview of the national situation regarding the silk industry in England, and of the particular problems besetting manufacturers during the late eighteenth and nineteenth centuries, is therefore essential to an understanding of the situation in the rural semi-industrial districts. The chapters of this thesis therefore follow the story of silk production from the wider context of the national industry to the specific mills of Hertfordshire, asking first, why the establishment of an English silk industry was so important. Themes explored in later chapters are already discernible in the early history of the silk industry: the high involvement of women; the apprenticeshipo f children; the interventionist role of government; and the problem of the poor. The extent to which these factors impinged upon the relationship between master, worker, and the local district, and ultimately upon the viability of the Hertfordshire mills, form the central core of this study.

Thesis (Ph. D.)--Columbia University, 1931. / Vita. Bibliography: p. 139-145.

京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13266号 / 論医博第2180号 / 新制||医||1038(附属図書館) / (主査)教授 妻木 範行, 教授 戸口田 淳也, 教授 椛島 健治 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

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Silk is a natural protein produced by members of the class Arachnida (over 30,000 species of spiders) and by several worms. Silk-based materials have been investigated for medical and biotechnological applications for many years. Although silkworm silk has been studied extensively because of ready availability of the protein, lately the advancements in recombinant technology has made production of spider silk proteins increasingly available. Due to the characteristics like biocompatibility, biodegradability and mechanical strength, silk is highly desirable as a biomaterial for medical purpose. Along with this, techniques for functionalization, has further aided in the development of silk into highly sophisticated material for advanced applications. The main objective of this thesis has been to investigate novel strategies for functionalization of the recombinant spider silk protein Masp2. Two distinct approaches were used, chemical modification and genetic fusion. In the first modification, we created an infection responsive silk nanospheres by chemically grafting a thrombin sensitive peptide to the silk protein encapsulating antibiotic. These particles were then evaluated for in vitro infection responsive drug release and antimicrobial activity. From these assessments, we found that these particles can release the drug effectively in the presence of infection providing the evidence that these particles are enzyme responsive and can be used to formulate targeted drug release. In the second modification, spider silk was genetically modified with a heparin binding peptide to create a fusion protein which can prevent both thrombosis and infection simultaneously. This fusion protein was evaluated for its heparin binding ability and anticoagulant properties in its solution form. Furthermore, due to the similarity in structure of HBP with antimicrobial peptides, it is predicted that the fusion protein will also show antimicrobial property. After establishing these properties, next this fusion protein was utilized as a coating for hemodialysis catheter. Deposition of coating was evaluated after which anticoagulant and anti-infective properties of the protein as a coating material was investigated. This thesis provides evidence of successful production of a recombinant silk-based biopolymer that can be chemically and genetically embedded with a various functional motif to create a hybrid product for different applications.

The ambient temperature of an environment has potential to influence many aspects of the behavior and physiology of small-bodied ectotherms, including brush-legged Wolf spiders Schizocosa ocreata (Hentz, 1844) (Araneae: Lycosidae). Temperature varies significantly, and often unpredictably, in their habitat throughout the spring breeding season, and is known to influence male Schizocosa courtship behavior. Currently unknown is what effect fluctuations in ambient temperature alone might have on critical, non-behavioral sexual signals such as female silk and chemical cues. We collected cues from mature, virgin females and subjected each sample to one of three thermal treatments (40°C, 20°C, or -12°C), at constant humidity. We presented treated female cues to mature males and recorded male response across treatment types as a behavioral indicator of signal degradation. There were no significant differences across treatments in the frequency or duration of male behaviors, including critical courtship and exploratory behaviors. Our results suggest that thermally induced degradation of female sexual signals is negligible for this species and likely has little or no influence on male behavior.

Spider silk has the potential to be a useful biomaterial due to its high tensile strength and elasticity. It is also biocompatible and biodegradable, making it useful for wound dressings and sutures, tissue and bone scaffolds, vessels for drug delivery, and ligament and tendon replacements. In some studies where spider silk has been used to grow cells, the silk has promoted more cell growth than the control. However, it is difficult to obtain the high volume of silk needed for these undertakings on a large scale. Spiders are territorial and cannibalistic, so they cannot be easily farmed. Therefore, spider silk proteins are frequently produced in other organisms. E. coli is often used for spider silk production due to the relative ease of gene manipulation and the cost effectiveness of large-scale fermentation. However, due to the large protein size of the spider silk and the repeating amino acid motifs, there are some challenges with production in E. coli. Metabolic modeling is a way to model the metabolism of an organism and can help overcome some of the difficulties of spider silk production in E. coli by predicting metabolic engineering strategies. In this study, a metabolic modeling tool known as dynamic FBA predicted that ammonium is depleted during cell growth. Laboratory results confirmed that by adding additional ammonium to the medium, the E. coli cells experienced more cell growth and were able to produce more spider silk protein