21794 research outputs found
Sort by
Leveraging Convolution And Self-Attention Mechanisms For Enhanced Feature Extraction In Medical Image Segmentation
No full textDeep learning has transformed the landscape of various scientific fields, including computer vision, natural language processing, and medical image analysis, with both convolutional neural networks (CNNs) and transformers emerging as a cornerstone in healthcare informatics and biomedical imaging for tasks such as image classification and segmentation. Particularly, U-shaped networks have shown remarkable efficacy in medical image segmentation, crucial for enhancing the precision of medical diagnostics and treatments by extracting significant details from intricate image data.
In this thesis, we introduced a novel architecture termed SwinAttUNet, which integrates convolutional and transformer-based networks. The thesis focuses on the automatic 3D segmentation of multiple organs in CT images, enhancing accuracy and efficiency in medical diagnostics and treatment planning. The SwinAttUNet architecture benefits from a dual-branch encoder combining convolutional and Swin Transformer elements, and an attention-enhanced decoder, ensuring precise and detailed organ segmentation. This hybrid approach leverages both local and global image features, significantly outperforming existing segmentation methods. The study validates the model\u27s effectiveness through extensive testing on diverse datasets, showcasing its potential to transform clinical workflows and improve patient outcomes
Developing Peptoid-Based Inhibitors For Uchl5 Deubiquitinase
No full textThe ubiquitin-proteasome system (UPS) plays an important role in degrading unwanted and damaged intracellular proteins. The 26S proteasome is composed of two domains, named 20S proteolytic core particle (CP), and 19S regulatory particle (RP). Proteasome identifies its targets once ubiquitin (Ub) molecules are conjugated to the substrates. The enzymes known as deubiquitinases (DUBs) are involved in the cleavage of the isopeptide bond between Ub and target proteins, which is named deubiquitination. The 19S RP of the proteasome is associated with three DUBs named regulatory particle subunit number 11 (RPN11), ubiquitin-specific protease 14 (USP14), and ubiquitin C-terminal hydrolase L5 (UCHL5). UCHL5 has two main domains. The catalytic domain is composed of a catalytic triad which acts as a cysteine protease. The C-terminal domain is involved in binding with RPN13 in the 19S RP of the proteasome. UCHL5 is known to be overexpressed in many cancers such as ovarian, and esophageal squamous cell carcinoma. It also promotes tumor cell survival, migration, and invasion in various cancers such as hepatocellular carcinoma by deubiquitinating and stabilizing proteins associated with cancer progression such as TGF-β-1. Therefore, it has emerged as a promising drug target. UCHL5 possesses protein-protein interactions (PPIs) with Ub and RPN13. We hypothesized that PPI disruption between Ub and UCHL5 might decrease UCHL5 activity. Peptoids have been used to disrupt PPIs and identified as highly proteolytic-resistant peptidomimetics. Therefore, we sought to develop a one-bead one-compound linear peptoid library using submonomer solid phase synthesis and the split-pool method. The library was used for on-bead screening with UCHL5, along with in-silico screening, to identify potential hits. Hits LP16, LP7, LP15, LP11, and LP2 were identified as hits to conduct in-vitro evaluation. LP16, LP7, LP11, and LP2 did not show inhibition of UCHL5 activity. However, LP15 showed an inhibition of UCHL5 enzyme activity. We also developed a one-bead two-compounds cyclic peptoid library to identify cyclic peptoid-based inhibitors for UCHL5. CP3 and CP6 hits were identified as candidates for in-vitro evaluation, from on-bead and in-silico screening of the library with UCHL5. However, neither compound showed inhibition of UCHL5 activity. Therefore, further optimization of the library such as peptoid chain length and primary amine building block diversity would be needed to identify the effective UCHL5 inhibitors
“i’ll Do It Myself” Exploring The Medical Experiences Of Black Women During The Perinatal Period Using Sister Circles: A Case Study
No full textThis study aimed to explore Black women\u27s narrative during the perinatal period using a culturally relevant conversation strategy called Sista Circles. Sista circles were used to gain knowledge from the perspective of Black mothers about their experiences with medical professionals during the perinatal period. The research questions focused on (1) how Black women navigate medical spaces during pregnancy and postpartum and (2) the impact a clinician-led group has on the mental health and perinatal experiences of Black mothers. The Sista Circle groups were conducted virtually, with two separate groups running simultaneously, with six members in each group. Participants were between 21 weeks pregnant and 12 weeks postpartum. Each session yielded a different topic to help participants engage in meaningful dialogue. The weekly groups were recorded, transcribed, and analyzed for emergent themes. The Sista Circle groups yielded two overarching themes when considering how Black mothers navigate their medical experiences during the perinatal period: (1) Illuminating the Power of Black Providers and (2) Unpacking Strong Black Woman Schema (during Pregnancy and the Postpartum Period). Within the latter theme, four sub-themes emerged: (1) Displaying of Strength, (2) Black Mothers\u27 Concerted Help Seeking Behaviors, (3) Suppression of Emotions, and (4) Desire for Knowledge. When exploring the impact of a clinician-led group on Black mothers, findings revealed that participants inherently felt comfortable in the group space and the importance of support groups for Black women, not only during the perinatal period but in all facets of life. The study highlights the impact of gendered racism in the medical field on Black women. This project emphasizes how Black women have identified nontraditional coping mechanisms to maintain their safety and the safety of their babies while dealing with the high Black maternal mortality rate in America
Beyond A Will: Shakespeare And The Reconception Of Inheritance
No full textWhen the term inheritance is mentioned, often it is thought of as only the passing on or receiving of tangible goods such as money, titles, or land. Early modern England in particular looked to define inheritance through laws built around a system of primogeniture. These laws were meant to create a straightforward understanding of how one’s legacy would be passed down to heirs, yet in practice it can be seen how open to interpretation such laws and ideas around inheritance were. This project moves beyond seeing inheritance as simply a legal topic and looks at the ways in which inheritance is instead a process by which individuals create their sense of self and their relation to their culture and community. This dissertation seeks to show the more abstract ways in which inheritance was understood in early modern culture through Shakespeare’s plays. The chapters in this dissertation look at Shakespeare’s utilization of the different play genres of history, comedy, and tragedy to present inheritance as it was understood both personally and communally. This project hopes to show how vital the topic of inheritance was in early modern conceptions of self and their relation to the culture in which they lived
Broadening Participation In Open Source Software Communities With Newcomers\u27 Onboarding And Retention
No full textOpen Source Software (OSS) projects depend on the contribution of new and existing developers. However, a significant number of newcomers fail to become long-term contributors because they face many barriers on their road to becoming long-term contributors. Because of receiving low-quality and delayed feedback, many newcomers do not return to contribute to the project. Prior studies found that timely and useful review feedback and proper mentoring from experienced developers can increase the retention of newcomers. Therefore, this dissertation aims to foster OSS communities with tools and guidelines to assist newcomers’ onboarding and retention. On this goal, I plan to empirically investigate: (i) What are the characteristics of useful review comments, and which contextual and participant factors influence the usefulness of review comments, (ii) how to facilitate automatic classification of code review comments and (iii) which task-related recommendations are practically influencing the newcomer onboarding process
Asexuality in Science Fiction: A Study of Non-Sexual Queer Intimacy in Short Stories by Ursula K. Le Guin, Samuel Delany, and Theodore Sturgeon
Get PDFThe study of asexuality is still a relatively new concept in queer studies, and the rarity of asexual literature poses questions about how media can help further develop this study. This question takes unique shape in the genre of science fiction, one deeply and intrinsically tied to queer storytelling but very often hypersexualized. This essay evaluates the asexual themes of four sci-fi short stories which predate modern vocabularies and frameworks of asexuality: “The Widget, The Wadget, and Boff” by Theodore Sturgeon, “Unchosen Love” and “Mountain Ways” by Ursula K. Le Guin, and “Aye, and Gomorrah” by Samuel Delany. Referencing queer theory which suggests that asexuality can help expand understandings of queerness as a whole, this essay focuses not directly on modern ideas of asexuality, but rather how non-sexual intimacy interacts with overarching queer themes in each narrative. This also reveals a healthy assortment of asexual tropes in particular, as well as how these interact with other forms of narrative, including disability narratives, culture narratives, and gender narratives. Using this, in addition to genre and form analysis of science fiction and short fiction, this essay comes to a conclusion on the fundamental utility of short form science fiction in telling asexual stories. Ultimately, it seems that the strengths of both form and genre create a noteworthy and relatively unexplored opportunity to use the science fiction short story to further explore asexuality in literature and bolster queer studies
A Review of Strategies for Describing Offensive Archival Materials
Get PDFAs archivists concede that neutrality is impossible and non-action itself constitutes action, it follows that to treat reasonably offensive records as any other record is to apply an interpretation that they are innocuous, unremarkable, and uncontroversial. Archivists may perceive the stakes of describing these materials as particularly high, but they lack a comprehensive set of descriptive strategies to apply to these records. As a result, existing practices are likely to be local or ad hoc. This research aims to identify and explore descriptive strategies archivists use which serve to construct (or concede) the meaning that certain historical materials are potentially offensive using a combination of literature review, evaluation of finding aids and descriptive metadata, and exploratory interviews with archivists and other memory institution professionals
The Impact Of Education, Economic Downturns And The Removal Of The One-Child Policy On China’s Marriage Market And Birth Rate
No full textThis dissertation aims to identify factors contributing to the declining marriage market in China, beyond traditional explanations. We developed two theoretical models to supplement conventional studies, proposing social norms, education, financial and policy change play crucial roles in this decline. In Chapter 2, we introduced a two-stage expected utility model to demonstrate the impact of social norms on the marriage market before individuals seek marriage or divorce. We created social norm variables as proxies for age and divorce discrimination, we also use illiterate rate and college graduate rate to verify their impact on marriage and divorce rates. Our found individuals exhibiting risk-hedging behaviors. The remarriage ratio, the GDP per capita, negatively correlates with both marriage and divorce rates, and lower education levels negatively correlate with marriage rates, while higher education levels show no significant impact. Chapter 3 develops a theoretical model based on the marriage bargain model, illustrating how the removal of the One-Child Policy could negatively impact the marriage market. The model shows that under the new policy, women experience reduced gains of marriage, leading them to choose to stay single. Empirical data revealed inconsistencies in the correlation between variables and marriage outcomes, suggesting that some inconsistencies are due to policy changes while others indicate marriage as a risk-hedging measure. Chapter 4 focus on birth rates, conducting three empirical studies: one on the actual birth rates and two on the willingness to have children. The first study found that higher education levels negatively correlate with birth rates, alongside economic indicators like CPI. The second study revealed education levels negatively affect the willingness to have children, and women are less likely than men to want more children. The third study\u27s marginal analysis found that individuals with an ideal number of children of 1 or 2 showed decreased willingness to have children post-policy change, while those with an ideal number of children of 3 or 4 showed increased willingness. These results suggest that the removal of the One-Child Policy may not have had the intended effect, as financial constraints play a crucial role in birth rate outcomes
Hydrogen Detonation Diffraction
No full textWhen a detonation wave exits a confined tube into a less confined volume, it transforms from a planar wave into a spherical wave, which can result in either failure of the propagation mechanism or successful transmission. The balance of shock propagation and energy release in the detonation diffraction represents one of the most complex and unresolved phenomena relevant to gaseous detonations. Herein, a comprehensive exploration of diffraction phenomena is undertaken. The different diffraction regimes are characterized and the effect of inert diluent on the diffraction behavior of hydrogen-oxygen-diluent mixtures is investigated. Four distinct diffraction regimes: the subcritical outcome, reinitiation from shockwave reflection, the critical regime, and the super critical outcome, are identified and discussed. With simultaneous direct photography and Schlieren imaging techniques, previously unseen details of the detonation and diffraction processes are recorded and explained. The results of experiments indicate that the detonation Damköhler number, defined as the ratio of the characteristic flow timescale to chemical timescale, is an accurate diffraction outcome predictor
