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A Comprehensive Study Of Bills Of Materials For Software Systems
Get PDFSoftware Bills of Materials (SBOMs) have emerged as tools to facilitate the management of software dependencies, vulnerabilities, licenses, and the supply chain. Significant effort has been devoted to increasing SBOM awareness and developing SBOM formats and tools. Despite this effort, recent studies have shown that SBOMs are still an early technology not adequately adopted in practice yet, mainly due to limited SBOM tooling and lack of industry consensus on SBOM content, tool usage, and practical benefits. Expanding on previous research, this paper reports a comprehensive study that first investigates the current challenges stakeholders encounter when creating and using SBOMs. The study surveyed 138 practitioners belonging to five groups of stakeholders (practitioners familiar with SBOMs, members of critical open source projects, AI/ML practitioners, experts of cyber-physical systems, and legal professionals), using differentiated questionnaires. We interviewed eight survey respondents to gather further insights about their experience. We identified fourteen major challenges facing the creation and use of SBOMs, including those related to the material included in SBOMs, deficiencies in SBOM tools, SBOM maintenance and verification, and domain-specific challenges. We propose and discuss six actionable solutions to the identified challenges and present the major avenues for future research and development. We hope these solutions can be adopted by the community to improve SBOM formats, tools, and adoption, and thus, enable the full potential of SBOMs.Computer ScienceMaster of Science (M.Sc.
Analysis Of Calcium Activity During Early Neural Development
No full textCells typically maintain very low levels of cytosolic Ca2+ ([Ca2+]i), but transient changes in [Ca2+]i due to influxes of Ca2+ from the extracellular milieu or intracellular stores form the basis of calcium activity. The occurrence of diverse patterns of activity attributes, such as frequency and amplitude, has been considered a potential mechanism by which this simple ion can transmit signals to downstream effector molecules. These molecules in turn regulate a wide array of biological processes, including many aspects of early neural development. However, it remains unclear exactly which attributes of these calcium activity events (CAEs) are translated by the effectors. Therefore, understanding the correlation between CAE patterns and gene expression during early neural development can provide critical insight into the underlying mechanisms of nervous system development and patterning. To this end, we performed both in vitro and in vivo Ca2+ imaging and image analysis during early neural development in Xenopus. First, we compared calcium activity and presynaptic neural phenotype in vitro. We found that a high frequency of low-amplitude spiking activity correlates with neural progenitors and glutamatergic phenotype. In contrast, high-amplitude spiking correlates with GABAergic phenotype and neuronal cells that are committed to differentiation (tubb2b positive cells). Further analysis using entropy measure and Hurst exponent suggested that both tubb2b and GABAergic neurons display relatively predictable and persistent calcium activity. The results of our in vitro analysis necessitated an in vivo imaging to confirm that these characteristic calcium activity patterns in vitro match those present in vivo. More importantly, because of this dramatic impact of data analysis techniques on the conclusions drawn from a given dataset, we then critically examined in vivo Ca2+ imaging literature that focuses on early neural development. We found that techniques that are used to define what constitutes a calcium activity event vary widely across studies. In light of instances in which studies with seemingly similar experimental designs have reported dramatically different conclusions, we have outlined the potential impact of techniques that were used to determine what constituted the background signal, baseline activity, and a CAE. Finally, for our in vivo analysis, we first identified Ca2+ peak detection techniques (PDTs) that were commonly used in the recent in vivo imaging literature, generated a combinatorial range of PDTs, and then assessed how application of different PDTs impact the interpretation of spatial patterns of CAEs using simulated data. Further, we constructed a composite neural plate (CNP) by integrating images from disparate tissue regions of embryos. By using this CNP, we examined spatial patterns of CAEs using all the PDTs mentioned above. As in our in vitro study, tissue-specific clusters of CAEs can be detected in PDT-dependent manner in the placodal primordium and near the blastopore and chordoneural hinge. More importantly, unlike previous reports, we found spiking is not restricted to specific tissue precursors in the developing neural plate. This study not only resolves some of the discrepancies in the literature but also highlights the value of systematic application of multiple methods of data analysis to provide a complete picture of the often irregular, complex patterns of calcium activity during early neural development.Applied ScienceDoctor of Philosophy (Ph.D.
Where Land Meets the Sea
No full textGrade Level: High School Earth Science and Oceanography Students will use graphs of sediment cores to determine how coast lines change
Popular Culture, Politics, and the Papacy: The Alignment of Anglo-American Popular Music and the Modernizing Catholicism of John Paul II, 1979-1989
No full textThis thesis examines the alignment of popular political rock and teachings professed by Pope John Paul II surrounding three conflicts: The Troubles, The Falklands War, and the Cold War. Thematic topics include class struggle, the role of the Vatican as a global institution promoting peace and stability during the 1980s, and the trasatlanticism of the British popular rock.HistoryBachelors of Arts (BA
Cereal Killer: Diagnosing Oyster Diseases Using PCR
No full textGrade Level: High School Biology Understand the basis of the polymerase chain reaction (PCR) by constructing a model of the technique using cereal and pipe cleaner
Assessing the Orthogonality of Synthetic Genetic Circuits
No full textOrthogonality - or a lack of interactions between two biomolecules - is a key tenet of synthetic biology. It is crucial to optimal and predictable synthetic genetic circuit functioning. While orthogonality often is not assessed in the literature, many researchers are starting to focus on the importance of host-circuit orthogonality assessment. This project is the first step towards the design of a low-cost orthogonality measurement tool. In order to design this tool, there needs to be a comprehensive understanding of how the host cell is impacted when a genetic circuit is introduced. The goal of this project is to identify genes that are commonly differentially expressed in response to a genetic circuit. These genes serve as “markers” of a lack of orthogonality and thus could be used to measure and evaluate circuit orthogonality levels. In order to find these differentially expressed genes, our group conducted our own RNA-seq experiments and performed a comprehensive analysis of similar experiments in the literature to determine which genes are commonly differentially expressed when a genetic circuit is added to a host cell.BiologyBachelors of Science (BS
Racing For Rights And Peace / Defeating Massive Resistance And The Color Of Memory
No full textRacing for Rights and Peace: Mary Church Terrell and the Origins of Transnational Black Feminism This paper explores the transnational human rights and peacebuilding contributions of Black feminist transnational activists in the late nineteenth and early twentieth centuries, using the case study of Mary Church Terrell. Focusing on Terrell’s work within transnational women’s peace organizations, this work discusses how these trailblazing activists created a pathway for intersectional race-conscious human rights activism that unfolded throughout the twentieth century and continues today. This paper also examines how race informed different understandings of peace within women’s transnational peace organizations. Defeating Massive Resistance and the Color of Memory: Black and White Histories of Public-School Desegregation in Norfolk, Virginia This paper investigates white parent’s and white children’s experiences with Massive Resistance and school closures during the late 1950-1960 period in Norfolk, Virginia. This work explores the economic and social factors that led to the fall of Massive Resistance and opened schools for integration in Norfolk and explains why Norfolk is a unique site for analysis of Massive Resistance and school integration. This paper also explores white women’s memories of this period and includes oral history interviews of several former white students. By comparing the actions of white parents and memories of white students to the violent realities of segregation and Massive Resistance and to Black student memories, this work seeks to demonstrate the ways race shapes memory.HistoryMaster of Arts (M.A.