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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

Male Centered Universe: A Critical Analysis of the Role of an Action Heroine

Stump, Olivia January 2022 (has links)
Thesis advisor: Celeste Wells / This paper analyzes the rights and privileges Black Widow and Captain Marvel are afforded in their respective films coupled with audience perception to understand how that might inform the future of the action heroine genre. There is a stark contrast between the reception of Black Widow and Captain Marvel that is best understood through the release timing of the films along with the character’s plotline within the Marvel Cinematic Universe. Regardless, the rights and privileges each character is afforded in both films demonstrate a dimension of the female experience that had not been fully realized in the MCU prior to their release. Captain Marvel and Black Widow indicate a progression of female representation within the action heroine genre– both in frequency and quality. / Thesis (BA) — Boston College, 2022. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Communication.
22

Quantitative Shotgun Proteomic Analysis of Bacteria After Overexpression of Recombinant Spider Miniature Spidrion, MaSp1

Randene, Kathryn P. 01 January 2024 (has links) (PDF)
Spider silk has extraordinary mechanical properties, displaying high tensile strength, elasticity, and toughness. Given the high performance of natural fibers, one of the long-term goals of the silk community is to manufacture large-scale synthetic spider silk. This process requires vast quantities of recombinant proteins for wet-spinning applications. Attempts to synthesize large amounts of native size recombinant spidroins in diverse cell types have been unsuccessful. In these studies, we design and express recombinant miniature black widow (Latrodectus hesperus) MaSp1 spidroins in bacteria that incorporate the NTD and CTD, along with varying numbers of codon-optimized internal block repeats. Following spidroin overexpression, we perform quantitative analysis of the bacterial proteome to identify proteins associated with spidroin synthesis. Nano-liquid chromatography with tandem mass spectrometry (nLC-MS/MS) reveals a list of molecular targets that are differentially expressed after enforced mini-spidroin production. This list included proteins involved in energy management, proteostasis, translation, cell wall biosynthesis and oxidative stress. Collectively, this study unveils new bacterial genes to target by genetic engineering to overcome bottlenecks that throttle spidroin overexpression in microorganisms.
23

A Comparative Analysis of Open Source Dynamic Application Security Testing Tools / En jämförelseanalys av dynamiska testverktyg för applikationssäkerhet med öppen källkod

Chorell, Isak, Ekberg, Christoffer January 2024 (has links)
In today’s digital era, the increase of internet usage presents a growing challenge in cyber security. An increase in cyber attacks underscore the need for robust software systems to protect them. One way of detecting vulnerabilities is by using Dynamic Application Security Testing (DAST) tools, which simulate cyber attacks without knowledge of the internal structure of its target. This thesis investigates the four open source DAST tools Black Widow, Nuclei, Wapiti and ZAP in their ability to identify security vulnerabilities in web applications. A comparative analysis was performed, focusing on the tools vulnerability detection capabilities, how different web applications affect their results as well as their practical applicability. Each DAST tool was run against web applications, both with and without intentional vulnerabilities, where measures such as scan time and reported vulnerabilities were collected. The tools were also run against a benchmark to be able to calculate the metrics accuracy, precision, recall and F-measure. The results show that ZAP reported the most vulnerabilities, where Cross Site Scripting and SQL injection are the most common types, but also had the largest number of false positives. However, on the benchmark, none of the DAST tools had any false positives. It was also found that the architecture of the web application highly influenced the tools' attack capabilities. Conclusively, DAST tools can help to improve the security of web applications but come with some drawbacks and limitations. To achieve a more comprehensive scan, one can use more than one DAST tool, but it comes with a cost of longer scan times and an increase in manual effort to review the reported vulnerabilities.
24

Production of Synthetic Spider Silk

Hekman, Ryan Matthew 01 January 2018 (has links)
Spider silk is a material that both has impressive mechanical properties and is also environmentally friendly. Though there are limitless potential engineering applications for such materials, industrial production of spider silk has proven to be challenging. Farming silk from spiders, as is done with silkworms, is not a viable option for large-scale production of spider silk due to the venomous and predatory nature of spiders. Here, an attempt is made to express synthetic spider silk minifibroins heterologously in Escherichia coli, to purify the recombinant spidroins from cell lysate, and to spin them into artificial fibers through a biomimetic process. Silk minifibroins were designed to be similar to Major Ampullate Spidroin 1 from Latrodectus hesperus. Synthetic fibers were examined by scanning electron and light microscopy, and their mechanical properties were tested by a tensometer. Properties of synthetic silk were compared to those of native dragline silk from the same species from which their design was inspired, revealing synthetic silk fibers with lower breaking stress and breaking strain.
25

Generation of cDNA chips from the black widow spider, latrodectus hesperus, for gene discovery and expression profiling using microarray technology, and molecular characterization of a novel silk glue protein

Vasanthavada, Keshav 01 January 2005 (has links)
eDNA microarray technology has generated a tremendous amount of interest among biologists because of its promise to monitor the entire genome on a single chip, thus enabling researchers to have a better picture of the interaction among thousands of genes simultaneously. In the current study, this technology was used to print over 3,000 unknown genes from various silk glands of the black widow spider to profile their expression patterns and to identify novel candidates. Spiders are remarkable creatures because of their ability to make different silks, each with a specific function. Some of these silks have amazing mechanical properties, comparable to those of the finest synthetic materials. Several silk genes have been cloned from various spiders over the last few years, and the contribution of each of those genes in silk production has been identified. However, the majority of cellular and biochemical processes involved in silk manufacture remain a mystery. In our research, we attempt to identify genes that might be involved in silk assembly, on a global scale and investigate more about those genes and their interplay with other key biological molecules involved in silk manufacture. Our study showed that silking spiders for a certain period of time resulted in down-regulation of two important silk genes, ECP-1 and ECP-2. Both these genes are key molecules implicated for their role in maintaining the egg case architecture in the black widow spider.,-and we believe that these genes are also directly or indirectly involved in the manufacture of dragline silk. Microarray analyses also enable the discovery of several other interesting molecules, two of which could be accessory proteins involved in silk formation. Furthermore, in a separate study we also characterized a novel silk glue protein with unique ensemble repeats. In conclusion, we believe that the findings of this study will indeed be significant to silk researchers and material scientists alike and it will enhance our knowledge in understanding the mystery behind silk production.
26

Characterization of the large diameter fibers in egg case silk : identification of a core fibroin, TuSp1, and localization of fibroin-like molecules, ECPs, from the black widow spider, latrodectus hesperus

McMullen, Erin 01 January 2008 (has links)
Araneoid spiders use specialized sets of abdominal silk glands to produce up to seven different types of silks, each with diverse functional properties. At the time of these studies, fibroin eDNA sequences that encode egg case silk had not been reported in the literature. This study used conventional nucleic acid-nucleic acid screening of a eDNA library to isolate a novel gene, named tubuliform spidroin 1 , from the black widow spider Latrodectus hesperus. TuSp 1 was demonstrated to be selectively expressed in the tubuliform gland (the gland suspected for egg case silk production), and examination of the amino acid sequence revealed highly homogeneous repeats (184 amino acid ensemble repeats), a characteristic feature of fibroin sequences. Analyses of the ensemble repeats within the amino acid sequence of TuSp 1 revealed the lack of long stretches of polyalanine and glycine-alanine sub-repeats, which are commonly found in minor ampullate and major ampullate silks. Polyserine blocks and short polyalanine stretches were highly represented in the TuSp 1 amino acid sequence. Our data support the assertion that TuSp 1 represents the main constituent within egg case silk. This supposition is supported by the observation that the amino acid composition of raw egg case silk was strikingly similar to the amino acid composition predicted from the translated TuSp1 eDNA. Two additional constituents identified in black widow egg case, egg case protein 1 (ECP-1) and egg case protein 2 (ECP-2), were also partially characterized in this study. Using immunohistochemical approaches, we demonstrate that ECPs predominantly localize to the exterior of the large diameter fibers of egg cases. Additionally, these studies revealed smaller amounts of ECPs localized to the interior portion of the fibers. Collectively, these results support TuSp1 as the predominant fibroin within egg sacs as well as reveal a structural role for the ECPs, providing clues regarding the supramolecular structure of egg case fibers.
27

Evidence that aciniform silk and minor ampullate silk are major constituents of wrapping silk from the black widow

Reza, Ryan C. 01 January 2008 (has links)
Spider silk is one of the most remarkable materials produced in the natural world and its strength and extensibility are legendary. To date, the majority of studies have been performed on the following silks: dragline, capture spiral, and eggcase silk. The primary goal of this study was to characterize a lesser known silk type, called wrapping (swathing) silk, from Latrodectus hesperus. My research focused on elucidating the fibroins that make up the swathing silk. Perfonning MS/MS analyses on solubilized wrapping silk fibroins digested with trypsin, we demonstrate that a novel fibroin named AcSp !-like is present within wrapping silk. Consistent with this finding, SEM analyses reveal that wrapping silk is a composite material, containing at least three different diameter silk fibers. By using scanning electron micrographs, along with amino acid composition analyses and MS/MS analyses, we demonstrate wrapping material contains the fibroins AcSp1-like, MiSp1-like, MaSp1 and MaSp2. These are the first studies to reveal that minor, major and acinifonn silks are constituents of wrapping material.
28

Characterization of a family of cysteine rich proteins and development of a MaSp1 derived miniature fibroin

Chuang, Tyler Casey 01 January 2014 (has links)
Spider silk displays a unique balance of high tensile strength and extensibility, making it one of the toughest materials on the planet. Dragline silk, also known as the lifeline of the spider, represents one of the best studied fiber types and many labs are attempting to produce synthetic dragline silk fibers for commercial applications. In these studies, we develop a minifibroin for expression studies in bacteria. Using recombinant DNA methodology and protein expression studies, we develop a natural minifibroin that contains the highly conserved N- and C-terminal domains, along with several internal block repeats of MaSp1. We also characterize a family of small cysteine-rich proteins (CRPs) and demonstrate that these factors are present within the spinning dope of the major ampullate gland using MS analysis. Biochemical studies and characterization of one of the family members, CRP1, demonstrate that this factor can self-polymerize into higher molecular weight complexes under oxidizing conditions, but can be converted into a monomeric species under reducing conditions. Self-polymerization of CRP1 is also shown to be independent of pH and salt concentration, two important chemical cues that help fibroin aggregation. Overall, our data demonstrate that the polymerization state of CRP1 is dependent upon redox state, suggesting that the redox environment during fiber extrusion may help regulate the oligomerization of CRP molecules during dragline silk production.

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