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Effective Wordle Heuristics
Get PDFWhile previous researchers have performed an exhaustive search to determine an optimal Wordle strategy, that computation is very time consuming and produced a strategy using words that are unfamiliar to most people. With Wordle solutions being gradually eliminated (with a new puzzle each day and no reuse), an improved strategy could be generated each day, but the computation time makes a daily exhaustive search impractical. This paper shows that simple heuristics allow for fast generation of effective strategies and that little is lost by guessing only words that are possible solution words rather than more obscure words
Impacts of Stormwater and Land Cover on the Abundance, Transport, and Composition of Anthropogenic Litter in Urban Watersheds
Get PDFAnthropogenic litter (AL; trash) is defined as any manufactured item that ends up in the environment. AL consists of many different materials including glass, metal, and plastic, the latter of which typically represents a dominant constituent and has been a major focus of research. Plastic litter and other AL types are pervasive to all types of ecosystems, are persistent in the environment, and are increasing. Rivers are a major conduit transporting AL to oceans. However, rivers also retain and transform AL. More research is needed to understand AL dynamics within rivers, which will improve global models of AL movement and distribution. This work examined AL and plastic transport dynamics in rivers spanning a gradient of watershed positions and land cover types. In the first study we used cameras to quantify macroplastic movement in rivers before, during, and after floods (N=18 individual flood events at 10 locations in 3 different watersheds). Across all sites, macroplastic count during floods was positively related to both flood speed and magnitude. In our second study, we quantified the relationship between watershed land cover and watershed position on AL abundance and assemblage. We examined these relationships for both mass and number of particles. We found that the best predictors of AL by count were impervious surface and urban area. The relationships with AL mass were less clear. AL in the floating and overhanging zones was significantly different than AL found in the benthic and riparian zones. This is likely due to a difference in transport dynamics between low-density AL and high-density AL. These results will contribute to predictive models of macroplastic transport, which will help inform management and policies aiming to reduce freshwater macroplastic pollution
Investigating the Roles of Sirtuins During CVB3 Infection and Innate Immunity
No full textCoxsackievirus B3 (CVB3) is an enterovirus that chronically infects heart tissue, leading to dilated cardiomyopathy. However, no vaccines or antivirals exist for CVB3 infection or to treat CVB3-induced dilated cardiomyopathy, except for a heart transplant. Sirtuins (SIRTs), class III lysine deacetylases, have diverse and complex roles in cellular functions, contributing to energy production, NF-κB signaling, cell cycle regulation, and inflammation. Previous studies showed that SIRTs are essential for hepatitis B and A viral replication and regulate the IFN response during viral infection. However, the role of SIRT1 and 2 during CVB3 infection is entirely unknown. CVB3-infected SIRT1 and SIRT2 knockout cells saw a significant decrease in viral titers compared to wildtype cells, and preliminary studies indicate SIRT1 and SIRT2 protein levels are stabilized during CVB3 infection, co-localize with CVB3 replication complexes and inhibit interferon-stimulated gene promoter binding and transcription. These data lead us to hypothesize that SIRT1 and 2 play dual roles during CVB3 infection: promoting CVB3 replication directly and inhibiting the immune response
Regulation of Spermatogenesis by the BTB Transcription Factor Ribbon
No full textThe transcription factor Ribbon (Rib) plays an essential role in Drosophila testis development and function. Increased expression of rib throughout development results in significant morphology defects in the adult testis. If overexpression is limited to germ cells and somatic cells in the adult, more mild defects are observed. To better understand how Rib regulates spermatogenesis, we are interested in identifying its transcriptional targets in this context. Through bulk RNA sequencing, differential expression analysis, and subsequent filtering of results, we identified 301 genes with significant changes in expression when rib was overexpressed. Given the previously described role of Rib in the regulation of cell morphogenesis and cell-cell interactions during development, we were particularly interested in genes involved in cell adhesion and regulation of the cytoskeleton. Therefore, of these 301 potential Rib targets, approximately 10 genes of interest were selected for additional analysis due to their implications in cell adhesion or the cytoskeleton. At this time, we have confirmed that shortstop (shot), which encodes a cytoskeletal linker protein, and rhea, which is critical to cell-cell adhesion, are regulated by Rib, revealing that Rib may regulate spermatogenesis through control of the cytoskeleton and adhesion. Current evidence strongly suggests that Rib regulates spermatogenesis by controlling the expression levels of genes involved in the regulation of cell morphology
Testing Strategies To Develop a Mucosal T Cell Inducing Vaccine for HIV-1
No full textDespite numerous efforts, HIV vaccine is still not available. Because HIV Envelop protein varies among subtypes and isolates, it is impossible for one vaccine against HIV Env to induce neutralizing antibodies against all subtypes and isolates. Previous vaccine attempts inducing HIV-specific CD4+ T cells have even been shown to enhance the HIV infection because HIV preferentially infects activated CD4+ T cells. It is known that CD8+ cytotoxic T cells (CTLs) play an important role in controlling HIV infections. We hypothesize that a vaccine inducing only CD8+ CTLs but not CD4+ T cells will be effective in preventing HIV infections. Thus, we plan to design minigenes expressing only 9 amino acid long HIV Gag/Env CTL epitopes but not CD4+ T cell epitopes as the vaccine target antigens. As most of HIV infections occurs mucosally, we will use papillomavirus like particles (PV VLP) as a mucosal vector. We will make papilloma pseudovirus (PV VLPs packaged with plasmid expressing HIV CTL epitopes) as the vaccine
“I Really Like the Idea of Being the Source of Change”: The Perspectives of Black and Latine Youth Experiencing Low Income About How Personal Change Occurs in Out-Of-School Group Programs
Get PDFStructured out-of-school programs (OSPs) can be contexts in which youth can be producers of their own positive change (Eccles & Gootman, 2002). However, despite a considerable body of research documenting the benefits of participating in OSPs, there is a lack of knowledge about how youth of color in low-income communities define positive personal change in OSP settings. As a result, many OSPs and interventions designed for youth of color rely on adult practitioners’ or researchers’ perspectives of the change process, which may weaken program impact and fail to holistically meet youths’ developmental needs. This study uses a critical realist scientific paradigm to carry out an interpretive, phenomenological qualitative examination (Denzin, 1989; Cresswell & Poth, 2018) of youths’ perspectives on the program mechanisms that bring about their personal change. From this realist standpoint, change does occur via youths’ internalization of program experiences. The purpose of this study is to explore youths’ perspectives about how they internalize OSPs (curricula and relationships with instructors, each other, and other participants) and define personal change in an OSP context. This study addresses the following overarching research question: Since program impact occurs via youths\u27 internalization of the program offerings, what do youth perspectives tell us about how they internalize the experience of an out-of-school, high-dosage, strengths-based program? Specifically, this study aims to: (1) understand youths’ perspectives of personal change, including the nature of youths’ internalization processes; and (2) identify program elements that function as mechanisms of change that youth say are helpful and not helpful. Data were gathered based on feedback of 212 youth participants enrolled in OSPs using three different curricula in four neighborhoods in Chicago over a 17-year time span. Data consist of youths’ qualitative peer-to-peer program evaluation interviews with each other at the conclusion of each program. Qualitative peer-to-peer interviews were analyzed with NVivo12 using a causal thematic and content process analysis (Denzin, 1989; Maxwell, 2004). This research design is well suited to answer the present research questions because it can produce grounded, “rich descriptions” and explanations of internalization processes situated within real-life contexts (Miles et al., 2019). The qualitative data were coded initially to generate themes and compile a coding manual. Inter-rater reliability of coding manuals was achieved at 91%, which preceded the analysis of all qualitative data (Miles et al., 2019). Understanding how youth themselves define and experience meaningful personal change is important in mitigating the traumatizing impact of epistemic violence and for optimizing services to improve care and promote healthy, culturally relevant practice models of youth development. The findings of this study represent a realist interpretation of SUHO, LYLL, and LUCM’s efficacy (Pawson & Bellamy, 2006). In other words, the causal power of these programs lies in their underlying mechanisms. Youth identified program mechanisms that they prioritized, which are represented by the themes that emerged from their peer-to-peer interviews. The results of this study indicate that youth strongly value having positive connections with peers and instructors in their program and suggest that the process of relating to others helps develop their own personal identity and sense of self. They also describe program mechanisms that facilitate the developmental need of relating to others. Moreover, there are many youth responses suggesting that the OSPs were impactful in part because they enabled youth to consolidate a positive identity (“I’m a good person”). This did not occur via curricula about self-affirmation or positive thinking (a more cognitive behavioral approach) but was connected by youth with the experience of feeling respected, heard, cared for, and affirmed by instructors and peers (a more humanistic approach). The mechanisms of action described by youth lead to specific guidelines for intervention providers, elucidated in this study. The theories of therapeutic change developed from adult treatment do not fully encompass the unique aspects of clinical work with youth. With a practice knowledge base rooted in this study’s findings about youths’ subjective meanings and experiences of services, social work practitioners can design practice models that are more suitable and relevant to youths’ cultural strengths and existing strategies of healthy development. Approaching out-of-school program design with an emphasis on human rights, humanistic group therapy, participatory approaches and resistance-building processes could provide a theoretical framework that can contrast overly medicalized models and help social workers address the profession’s core values. By doing this, youth may see themselves as less pathologized by the “intervention” and view concepts of personal “change” in the program as defined by themselves, made possible by incorporating participatory elements throughout program design, implementation, and evaluation
Establishment of an In Vitro HBV Infection System and Investigation of a Recently Emerged HBV Genotype
No full textHepatitis B virus (HBV) research has been hampered due to the lack of experimental infection systems to study the virus. With the discovery of NTCP as a cellular receptor for HBV, transgenic HepG2-NTCP cells offered promise as an infection model, but several limitations have hindered their usefulness for studying all aspects of the HBV life cycle, such as viral spread. Further, most research systems are based on HBV genotype D, with little regard to the other genotypes (A-J) even though the other genotypes have different clinical manifestations and response to treatment. The emergence of HBV genotype E (GTE) is particularly alarming due to its rapid spread throughout a large region in Africa suggesting possible antibody escape in vaccinated individuals. In this thesis, we improved the HepG2-NTCP cell-based infection system allowing for more physiologically relevant infection conditions that allow for HBV spread, and hopefully the study of all HBV genotypes, such as the emerging genotype, GTE. By interrogating the impact of different variables on HBV infection and spread in vitro, optimal virus handling to preserve infectivity and avoiding supraphysiological cellular NTCP levels were found to be key factors for achieving robust viral infection and spread. Additionally, antibody-resistant, NTCP-independent HBV spread was observed, suggesting a novel HBV cell-to-cell spread mechanism. Importantly, we show that HBV GTE has increased expression and altered antigenicity of the viral surface proteins which could contribute to vaccine/immune escape. Overall, this optimized, more physiological relevant HBV infection system allows for study of all aspects of the viral life cycle and should facilitate expansion of research to different HBV genotypes, both of which will ultimately aid in antiviral drug discovery
Jesus, the Temple, and Early Christian Memory
Get PDFJewish identity during the Second Temple period (515 BCE – 70 CE) was complex, multifaceted, and variable, but many studies of this period treat Jewish attitudes toward one key feature, the Jerusalem temple, as simple and uniform. I aim to complicate this notion by examining early Christian traditions of Jesus’s relationship with the temple. Early Christian memory constructed, transformed, and transmitted traditions about the past into their present contexts. Examining early Christian memory, as represented by canonical and non-canonical gospel traditions in the first three centuries CE, allows scholars to ask how certain figures, institutions, or beliefs were remembered and represented, as well as posit theories as to why memories were constructed in particular ways and how they relate to their contemporary historical and social frameworks. In this study I explore the realm of memory theory as a means of examining the relationship between the present and the past. I survey the ways in which memory theory has been introduced into New Testament studies and has focused on gospel traditions as a means of remembering Jesus. I chart paradigms of Jewish identity within Second Temple Judaism and give particular focus to attitudes toward the Jerusalem temple. Finally, I examine gospel traditions, particularly the Gospel of Mark, that demonstrate the early Christian reception and remembering of Jesus’s attitude toward the temple in both positive and negative ways, then situate these traditions within the larger context of the social, cultural, and historical frameworks of Jewish attitudes in the Second Temple period. Early Christians remembered Jesus as having a complex relationship with the Jerusalem temple, and these early Christian traditions of Jesus impacted their own contemporary worldviews. However, this complicated relationship with the temple was not a new phenomenon but one that was already familiar to those constructing, experiencing, remembering, and transmitting their Jewish identity throughout the diaspora world in the Second Temple period
Napping, Sleep, and Affect in Adolescents: A Daily Diary and Actigraphy Study
Get PDFAdolescents in the United States do not typically attain enough quality sleep at night due to a combination of biological maturation and academic and social commitments, leading to poor cognitive, mental, and physical health outcomes. Naps may compensate for inadequate sleep; however, little is known about how napping affects nocturnal sleep and mood over time among adolescents who are poor sleepers. The present study used daily diary and actigraphy data collected over 15 days in a sample of evening-chronotype, poor sleeping adolescents (n=99; Mage=15.85 (SD=0.99); 44% Male, 55% Female; 46% White, 30% Black, 12% More than one race, 8% Other, 2% Asian, 1% American Indian or Alaska Native). The majority of participants (n=76) napped at least once during the study period, and almost one fifth of the sample (n=17) demonstrated “habitual” or frequent napping. Nap occurrence was associated with a decrease in total sleep time by 27 minutes as well as later sleep onset time that night. Later nap offset time was associated with later sleep onset time, and longer nap duration was associated with later sleep onset time and lower sleep efficiency. Napping was unrelated to the affect. Finally, late nappers demonstrated shorter total sleep time when they took a nap and when they took a longer nap as compared to early nappers. Findings indicate that napping is common and generally associated with worse nocturnal sleep outcomes among adolescents. Future work on napping is needed to guide recommendations for optimizing these daytime bouts of sleep to support healthy functioning
An Insider\u27s Perspective to Mentoring Novice Math and Science Teachers in a University Mentoring Program: A Self-Study
Get PDFNovice teachers benefit from individualized and cohort mentoring to help them successfully navigate student teaching and the first years of independent teaching. However, schools are experiencing a rise in attrition rates post-pandemic, especially in math and science. Mentoring, goal setting, and community-building are deemed important for retaining novices and providing them with individualized support as they navigate instructional challenges and professional responsibilities. This self-study investigates the experiences of a mentor while leading a new Professional Development & Mentoring Program for math and science novices. Educative mentoring and Hegarty’s Reflective framework helped guide the reflections of the mentor as mentoring strategies and programming were evaluated. The mentor identified areas of strength and growth and understood how mentoring, goal setting, relationship building, and the established learning communities were mutually beneficial for the novices and mentor. The findings and implications presented in this dissertation can prove valuable for universities and schools seeking to improve their mentor\u27s experience as they lead supplemental induction and mentoring programs