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Talking Machines: Philosophical Essays on Language Models
No full textThis dissertation is a collection of three independent but thematically connected papers on language models. The first assesses a currently popular account of the nature of the linguistic competence ostensibly manifested by LMs. According to this account LMs are “stochastic parrots”, whose linguistic outputs, though they look outwardly meaningful, are actually only cleverly stitched together bits and pieces of language which have no meaning at all except accidentally. This claim depends on what I call the Communicative Intention argument. In this chapter I demonstrate that the argument is largely driven by strong Gricean assumptions about the nature of linguistic competence that I argue are now known to be empirically untenable. Moreover, I show that once we give up these assumptions and fairly assess the architecture of both LLM and human cognitive architectures, we will find no good reasons to suppose large language models lack communicative intentions. The second paper addresses the larger debate in the context of which the Communicative Intention argument is made: the debate about meaning in LMs. I argue here that there are two senses of “meaning” in the debate, which I term semantic meaning and content meaning. A failure to distinguish between these two varieties of meaning has led to many of the characteristic confusions in the debate. The final paper deals with metalinguistic capacities in LMs. This paper introduces a novel way of accounting for any ostensible differences in the competences manifested by humans and LMs. The account has to do with what I call metalinguistic agency — roughly, the claim is that the agential structure of the linguistic competences in LMs and humans differ; any ostensible differences between them can be accounted for in terms of this difference in agential structure
Nanoscale Hydrophobic Interactions of Neurotoxic Dipeptide Repeats with the Nuclear Pore Complex as Revealed by Transient Scanning Electrochemical Microscopy
No full textThe goal of this thesis is to understand the role of the nuclear pore complex (NPC) as the sole gateway for nucleocytoplasmic transport of eukaryotic cells. Specifically, I will discuss how neurotoxic dipeptide repeats (DPRs) block the proteinous nanopore to potentially cause neurological diseases, e.g., amyotrophic lateral sclerosis and frontotemporal dementia. I will measure and quantitatively analyze the thermodynamic and kinetic interactions between NPC transport barriers and DPRs to understand how the NPC engages in selective and efficient molecular transport, which is biologically and biomedically important.
To achieve these goals, transient scanning electrochemical microscopy (SECM) is developed, using a micrometer-sized electrode with an interface between two immiscible electrolyte solutions (ITIES) to probe DPR transfer across the liquid/liquid interface to determine the strength and kinetics of NPC–DPR interactions and concentration of interaction sites in the NPC. Chapter 1 is an overview of this thesis. Chapter 2 reviews recent developments and applications of nanoscale ITIES electrochemistry, including previous studies on monovalent ion diffusion through porous membranes and the NPC to establish the structure–permeability relationship, used in later chapters. In Chapter 3, the theory behind the transient method is modeled by the finite element method to determine the three parameters separately, instead of determining the overall permeability as the three combined using steady-state measurements.
In Chapters 4 and 5, interactions of authentic NPCs with arginine-containing DPRs are quantified for the first time to reveal both cation-π and hydrophobic interactions. DPRs associate with the NPC as strongly as nuclear transport receptors but dissociate much more slowly to have longer dwell times, proposed as a potential cause of neurotoxicity. The length of DPRs is also varied to be used as molecular probes to engage in hydrophobic interactions with the transport barriers, revealing that larger DPRs associate more strongly with and remain longer to clog NPCs, supporting the hypothesis of NPC transport utilizing hydrophobic interactions. Similar free energy changes determined for transfer into the NPC and nitrobenzene suggest their similar hydrophobicity. This demonstrates the potential for liquid/liquid interface to model other hydrophobic proteinous environments beyond bilayer lipid membranes, as exemplified by NPC transport barriers
Growth in parent-child relationship during early childhood in predicting school-age functioning in a racially diverse sample
No full textThe importance of the parent-child relationship during early childhood (i.e., 0-5 years) on children’s socioemotional functioning has been extensively documented in the literature. However, limited work has examined the degree to which affective features of the parent-child relationship change over the course of early childhood and whether growth in these features relate to children’s early school-age functioning. The present study aimed to address this limitation by examining trajectories of maternal positive regard, maternal negative regard, and dyadic affective mutuality in very early childhood and whether these trajectories were associated with child socioemotional functioning at age six. The initial sample was comprised of 403 low-income, infant-mother dyads recruited for an efficacy trial of a tiered parenting program designed to promote school readiness. Positive regard, negative regard, and affective mutuality were assessed via coding of observational interaction tasks between mothers and their children at 6, 18, 24, and, in one case, 48 months. Mothers reported on children’s problem behavior, inhibitory control, and positive social behavior at 75 months (i.e., age 6). Results from latent growth curve analysis revealed that maternal positive regard quadratically changed from 6-48 months, maternal negative regard linearly decreased from 6-24 months, and dyads’ affective mutuality linearly increased from 6-24 months. Positive regard and affective mutuality at 6 months did not relate to child outcomes at 75 months. However, linear growth in affective mutuality from 6 to 24 months positively related to 75-month child inhibitory control. Maternal race and ethnicity did not moderate any of the relationships explored in the present study. Pending replication, these findings could emphasize the importance of conducting work that centers the dyad as the unit of study and explores how early changes in the parent-child relationship may be important indicators of children’s future self-regulation
Educational Screen Time and Young Children: A Quantitative and Qualitative Analysis
No full textThe ubiquity of screen time (ST) for young children has prompted extensive investigation of its impacts on child development. Extant experimental work has demonstrated that educational ST and interactive educational ST have positive impacts on children’s academic skills, but very limited work has examined these associations in naturalistic settings. Even less work has examined whether self-regulatory skills support children’s learning through educational ST. Additionally, much of the existing qualitative work investigating parents’ attitudes have focused on ST more generally, with little focus on attitudes towards educational ST specifically. The current project places an emphasis on the role of educational ST and parent attitudes about educational ST by drawing on quantitative and qualitative data from a longitudinal study of 4-year-old children. In study 1, I deployed time diary data to measure children’s educational ST and interactive educational ST as well as direct assessments of children’s math, spatial, and literacy skills. I found that children’s educational ST at age 4 was significantly predictive of literacy skills measured at age 5, but there were no significant findings related to interactive educational ST or interactions with self-regulation skills. In study 2, I used qualitative data to explore parents’ attitudes associated with educational ST and whether there were qualitative differences between parents’ attitudes as a function of their children’s use of educational ST. I found generally that parents held mostly positive attitudes about educational ST, but several barriers to encouraging its use were identified. Few qualitative differences in how parents described their educational ST attitudes surfaced. Together, these results suggest that educational ST used at home may promote children’s literacy skills, and parents’ positive attitudes about educational ST may not necessarily translate into behavior
Experimenter Demand Effects
No full textExperimenter demand effects arise when participants in an experiment or survey distort their behavior in a misguided attempt to please the experimenter by confirming their research hypothesis. Experimental economists have taken the threat of demand effects seriously and have developed an array of best practices to mitigate their influence, as well as bounding techniques to assess their potential impact on inference. We provide an overview of these techniques and summarize recent empirical assessments of the potential threat of experimenter demand. Our main message is that good design is normally sufficient to address demand concerns, and that bounding approaches work well when concerns remain. Existing empirical evidence suggests that the potential impact of experimenter demand is limited
Development of Small Molecule and Antibody Adaptors for Programming of Universal CAR T Cells
No full textThe field of immunotherapy has grown drastically since the introduction of CAR T cell therapy, which is introduced in Chapter 1.0. Methods of conditional control to reduce off-target toxicities associated with CAR T cell therapy are discussed in Chapter 2.0. Additionally, the SNAP-CAR system, developed by the Deiters and Lohmueller labs, is introduced and further explored in Chapter 3.0. In Chapter 3.2, site-specific antibody conjugation is utilized and compared directly to previous adaptors made via heterogeneous modification. Additional advantages of these site-specific adaptors are discussed in the context of ADEPT as a therapeutic in Chapter 5.0. As an alternative to using antibodies to target antigens on cancer cells, small molecule adaptors are explored as targeting ligands in Chapter 4.0
Zed Beats: A Historical Ethnography of Musical Production and Musical Labor in Zambian Popular Music
No full textDrawing on participant-observation, interviews, musical analysis and published literature on Zambia’s socio-economic history, I analyze shifts in musical labor and musical production of Zambian popular music between 1986 and 2024. I define musical labor as any activity that contributes to the production of music in recording studios and other creative spaces for financial gain or otherwise. Zed Beats, a blend of indigenous Zambian musical elements with musical influences drawn from R&B, reggae, rap, Jamaican dancehall, hip-hop, and other music genres, exposes these shifts.
Socio-economic conditions prevalent in the late-1980s and 1990s, including the decline of Zambia’s economy, the rise in the number of disk jockeys (DJs) and their mobile discos, the dominance of foreign music on Zambia’s radio and television, the demise of many musicians due to HIV/AIDS, and the economic liberalization of Zambia’s economy, facilitated shifts in musical labor and musical production in recording studios.
This dissertation consists of five chapters. In Chapter 1, I present the history of Zambian popular music and examine the socio-economic conditions that led to the emergence of Zed Beats and its subgenres in home studios. In the second chapter, I analyze musical labor and musical production in semi-professional studios between 1986 and 2000 before the emergence of Zed Beats. In chapters three and four, I examine shifts in musical labor and musical production based on ethnographic research I conducted in Zambia between 2021 and 2024. In Chapter 5, I analyze the seeming omnipotence of producers in home studios as they transformed their Digital Audio Workstations (DAWs) into musical instruments. The producer’s omnipotence in the production of Zed Beats has significantly influenced its sound and blurred the roles of the musician, engineer, composer, arranger, songwriter, and producer in home studios. In this chapter, I further explore “liveness” as an aesthetic choice by producers who have reincorporated live instrumentation in the production of Zed Beats. I demonstrate how producers’ access to more affordable audio recording equipment, music software, computers and other related accessories has given them a new kind of influence and power over the production of popular music in Zambia
Liver Cancer Disparities in the United States and Pennsylvania: A Surveillance Review
No full textLiver cancer is a major global health issue, with approximately 905,677 new cases and 830,180 deaths annually. The incidence of liver cancer varies by demographic factors such as sex, race, and ethnicity, underscoring the need for prevention and treatment strategies. This surveillance review examines liver cancer trends in the United States, with a focus on Pennsylvania, from 2010 to 2021. United States data was obtained from SEER-reported values and Pennsylvania was obtained from Pennsylvania Department of Health cancer and population datasets. There have been significant racial and ethnic disparities observed in liver cancer rates. In Pennsylvania, the highest incidence was among Black populations, followed by White, Asian and Pacific Islander, and Hispanic people. While Hispanics have the highest liver cancer rates nationwide, Pennsylvania shows lower rates in this group compared to others. Males consistently had higher rates than females, with Asian and Pacific Islander males aged 65 and older showing particularly high rates. Age-specific trends revealed that liver cancer rates increase significantly in the 50-64 and 65+ age groups. These findings highlight the need for further research into the factors contributing to these disparities, including differences in healthcare access, socioeconomic status, and chronic liver disease burden. Targeted interventions and screening procedures are needed for high-risk groups. Public health strategies should focus on enhancing liver cancer screening and ensuring equitable healthcare delivery. Addressing these disparities is critical for public health significance in reducing liver cancer incidence and mortality and improving outcomes for all populations
Hepatitis C and HIV outbreak preparedness planning in Allegheny County: a health services assessment survey
No full textBackground: The United States is experiencing a syndemic of hepatitis C, HIV, and opioid overdose. As a result, incidences of hepatitis C and HIV are rising among people who inject drugs (PWID). In response to the rapid transmission of hepatitis C and HIV among PWID, the Allegheny County Health Department (ACHD) conducts an annual survey of facilities that work with clients at high risk of experiencing these outcomes to inform outbreak preparedness planning.
Methods: The ACHD contacted 73 facilities that provide services to county residents for the 2023 survey. The sample included substance use treatment clinics, HIV programs, homeless service providers, Federally Qualified Health Centers (FQHC), correctional facilities, and syringe service providers. Forty-eight (66%) facilities responded to the survey that assessed the availability of prevention, testing, and treatment services.
Results: The 2023 survey found that many facilities provide linkage to hepatitis C and HIV testing and treatment. Of the responding facilities, 79% (n=38) provided access to hepatitis C antibody testing, 71% (n=34) to hepatitis C RNA testing, and 85% (n=41) to HIV testing. Of the 42 facilities that provided information on hepatitis C treatment services, 81% (n=34) provided clients access to treatment. Many facilities worked with partner agencies that visit periodically to provide services. Partner agencies most commonly visit monthly, indicating that clients have limited access to testing and treatment services. Facilities most frequently cited “lack of staff training," “lack of supplies," and “concerns about cost/billing” as barriers to providing onsite services.
Conclusion and Public Health Significance: The 2023 facility survey provides insight into hepatitis C and HIV services available in Allegheny County. Additionally, the survey identified barriers to providing services that can help guide future interventions. Hepatitis C and HIV remain major public health concerns in Allegheny County, and the survey informs the department’s planning effort to detect and mitigate infectious disease outbreaks among populations at high risk of infection
Development of a Post Overdose Support Team (POST) for City of Pittsburgh Public Safety
No full textThe opioid crisis continues to pose significant challenges for urban communities, including Pittsburgh, where overdose rates remain high. This paper proposes the establishment of a Post Overdose Support Team (POST) in collaboration with the City of Pittsburgh Emergency Medical Services (EMS) and City of Pittsburgh Office of Community Health and Safety (OCHS) to provide immediate and ongoing support for individuals who have experienced an overdose. The POST will focus on a holistic approach, integrating emergency response with long-term recovery resources, including medical treatment, counseling, and community support services. By leveraging the existing infrastructure of Pittsburgh EMS, the team aims to ensure that overdose survivors receive critical follow-up care, thereby reducing the likelihood of repeat overdoses and promoting recovery. This initiative seeks to enhance public health outcomes, improve community safety, and foster a supportive environment for individuals battling substance use disorders. Through a combination of data-driven strategies and community engagement, the POST will serve as a model for effective intervention and support, ultimately contributing to a comprehensive response to the opioid epidemic in Pittsburgh