In this critical review of the literature, I interrogate the assumptions underlying STEM workforce studies as it pertains to gender, race, class, and citizenship. First, I provide a brief overview of the pipeline model’s history and critiques. Next, I look at the contemporary use of the model in STEM workforce studies, focusing on the ways in which recruitment and retention, scientific work, and identity are represented, measured, and understood. I argue throughout that the pipeline model has a limited view of retention that is based upon socially constructed ideas about what constitutes “valid” scientific and engineering work and who counts as “real” scientists and engineers.

The purpose of this dissertation was to assess the impact of the COVID-19 pandemic on the occurrence and identification of child abuse and neglect. The first study concurrently examined changes in identification and medical evaluations of maltreatment allegations from before to during COVID-19. Reports to social services and child maltreatment evaluation center medical evaluations were collected from two counties and compared across the months of March-December 2019 and 2020. Findings showed divergent trends in reporting and evaluation of suspected maltreatment cases from before to during COVID-19. Specifically, while reports of suspected maltreatment were lower in 2020 than in 2019, the proportion of children reported to the county that received medical evaluations was higher in 2020 compared to 2019. Studies 2A and 2B took a different approach, assessing the impact of COVID-19 on laypersons’ ability to identify the most common form of maltreatment, child neglect. To do so, adults read vignettes about a mother’s care of her daughter and responded to questions about the mother’s neglectfulness, their reporting likelihood, and their attributions of blame for the situation. Though most adults were able to distinguish situations with versus without neglect, some conflated poverty and neglect when making identification and reporting decisions. COVID-19 had an indirect, rather than direct, impact on these decisions. Moreover, attributions of blame partially explained laypersons’ perceptions and reporting decisions. Together these studies can help the developing public education efforts or alternative methods of identifying vulnerable children and intervening in situations of harm.

Magnetic resonance imaging (MRI) provides many ways to study human brain anatomy as well as advance our understanding of brain structure, function, and processes that occur with disease. This dissertation project investigated the clinical utility of new and existing MRI techniques to the study of changes that occur in the brains of patients with multiple sclerosis (MS). The new MRI techniques were developed and tested with the goal of attaining more sensitive methods for disease detection than those that are currently available to clinician scientists. These new bioengineering developments included both novel MR acquisition and data analysis techniques for improved non-invasive, quantitative assessments of multiple sclerosis disease processes.

There are many quantitative MRI methods that can be used to detect tissue differences in patient populations when compared to controls. This dissertation research probed the utility of volumetric measurements, T1-relaxation times, and diffusion tensor imaging (DTI) metrics to detection of tissue damage and disease in early stage MS. New DTI methods were developed and new ultra high-field MR hardware and techniques were investigated to examine their potential in identifying previously undetectable brain changes in patients. This bioengineering project included acquiring patient and healthy control data, MRI technique development and optimization, developing and implementing appropriate image-processing methods for parameter measurement, cross-sectional and longitudinal investigations, and determining appropriate statistical approaches for comparative studies.

It was determined that T1-relaxation and DTI measures of mean diffusivity (Dav), fractional anisotropy (FA), and transverse diffusion (EvT) were sensitive enough to detect brain tissue changes at the earliest presentation of disease. Although volume measurements were not different as a group at presentation, atrophy was detectable via volumetry at one-year post baseline. Additionally, DTI measures were able to predict this change, an indication of a causal relationship between microscopic damage and overall tissue loss. The diffusion technique development and high field MRI methods demonstrated the feasibility to collect images with advantages in image quality, signal to noise (SNR), resolution, and ability to detect disease over what was previously available. These developments provide the platform for future work in MRI and its application in MS to better characterize disease.

Glia are the protectors of the nervous system, providing neurons with support and protection from cytotoxic insults. We previously discovered that four astrocyte-like glia can regulate organismal proteostasis and longevity in C. elegans. Expression of the UPRER transcription factor, XBP-1s, in these glia increases stress resistance, longevity, and activates the UPRER in intestinal cells via neuropeptides. Autophagy, a key regulator of metabolism and aging, has been described as a cell autonomous process. Surprisingly, we find that glial XBP-1s enhances proteostasis and longevity by cell non-autonomously reprogramming organismal lipid metabolism and activating autophagy. Glial XBP-1s regulates the activation of another transcription factor, HLH-30/TFEB, in the intestine. HLH-30 activates intestinal autophagy, increases intestinal lipid catabolism, and upregulates a robust transcriptional program. Our study reveals a novel role for glia in regulating peripheral lipid metabolism, autophagy, and organellar health through peripheral activation of HLH-30 and autophagy.

Cell non-autonomous signaling of organellar stress response pathways requires the detection of stress, release of a signal, detection of that signal in a separate tissue, and activation of the same stress response pathway in peripheral tissue. Here, I investigate the role of another signaling pathway, TGF-ꞵ, in the cell autonomous and cell non-autonomous signaling pathways of the UPRER, UPRmt, and HSR. Interestingly, I find that knockdown of components in the TGF-ꞵ pathway, specifically the DBL-1/SMA pathway, leads to a myriad of effects on the activation of transcriptional reporters of the UPRER, UPRmt, and HSR.

This dissertation uses tools and models from labor economics to study two information problems in healthcare markets: the uncertainty of patients regarding the quality of medical care and the asymmetry of information between physicians and patients. These problems may lead to market failure and impact patient care, but our current understanding of the consequences of each is imperfect.

I first consider patients' difficulty in determining the quality of medical services, focusing on technical skill of cardiac specialists. While it is difficult for patients to judge the skill of cardiac specialists due to information problems, referring doctors may have access to quality information unavailable to patients. This chapter considers whether the referral relationship between primary care physicians and specialists mitigates problems arising from patients' lack of information in this context. In particular, I measure the extent to which referring doctors learn about specialist quality by observing patient outcomes and use this information to select specialists on patients' behalf.

This chapter presents a model of the referral relationship with public learning by PCPs about specialist quality. The model makes predictions for specialists' careers. In general terms, the model predicts that careers of specialists should diverge by quality over time. I test predictions of the model using the universe of Medicare claims filed by cardiac specialists in the U.S. from 1996-2005. Specifically, I compare careers of higher and lower quality specialists using a new measure of specialist quality that is robust to nonrandom patient sorting. The evidence suggests some degree of learning by PCPs: lower quality specialists are significantly more likely to drop out of the labor market and to change geographic markets over time. For young cohorts, learning also results in improved sorting of patients to providers based on risk characteristics over time.

The next chapter, which is joint work with M. Marit Rehavi, addresses the asymmetry of information between physicians and patients. Specifically, it measures the extent of agency problems arising from this inequality, focusing on the decision to perform C-sections. We do this by comparing the probability of receiving a C-section for physician-patients with the probability for non-physician professionals. The research design exploits the fact that physicians are better informed regarding the appropriateness of recommendations and treatments than the average professional. As such, treatments for this group provide a near-fully-informed baseline that allows us to isolate the effects of information and agency problems.

We carry out this analysis using vital statistics data from the state of Texas, including every registered birth from 1995-2008. We find evidence consistent with agency problems in the physician-patient relationship. Physician-patients are approximately 5% less likely to have a C-section than other highly educated patients, controlling for relevant medical factors. This difference is even larger when the mother is the physician, and it comes almost entirely from non-emergecy C-sections. Findings are consistent with significant agency problems, and these appear to have increased in importance over the sample period.

Callous-unemotional (CU) traits have consistently been linked to severe and persistent patterns of antisocial and aggressive behavior in adolescents. Though a lack of empathy has often defined CU traits, placing these constructs at opposing ends of the same continuum, there is reason to suspect that CU traits and empathy are not only unique constructs, but also relate to different outcomes. The present study sought to unpack CU traits and empathy in a more systematic manner, examining their unique contributions to externalizing behaviors, internalizing symptoms, and prosocial tendencies in a group of high-risk adolescents. We asked maltreated (n=92) and community-matched (n=75) 12 to 17 year-olds about their emotional and behavioral functioning. Maltreated youth reported higher levels of CU traits but did not differ from community youth on cognitive or affective empathy. Additionally, CU traits and empathy were related to unique forms of functioning – CU traits with externalizing behaviors, affective empathy with internalizing symptoms, and both with prosocial tendencies. Findings offer unique insight into the relations among CU traits, empathy, and adolescents’ functioning. Implications for interventions and potential directions for future work are discussed.