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Adolescents\u27 Dissociative Responses To Age-Typical Social Stressors: Links With Violence Exposure And Mental Health
No full textTheory and research have identified dissociation as a likely mechanism underlying the risk of mental health problems for violence-exposed youth. Dissociation is characterized by alterations and disruptions to consciousness, memory, self-identity, and perception of the environment. Theory posits that people develop high levels of trait dissociation following childhood interpersonal violence exposure which in turn manifests as state dissociation in response to everyday stressors. However, these associations have not been tested among adolescents.
Social interactions that evoke the dynamics of interpersonal violence—betrayal, stigmatization, and powerlessness (BSP)—may trigger state dissociation. For example, the betrayal of trust from a caregiver may render violence-exposed adolescents especially reactive to an age-typical relationship betrayal (e.g., a close friend spreads rumors about you). Using virtual reality (VR), we examined whether youth dissociate in response to age-typical social stressors that involve BSP dynamics and tested two pathways linking childhood IVE to state dissociation: emotion dysregulation and posttraumatic stress symptoms (PTSS).
Adolescents (N = 239, MAge = 15.87) participated in 12 VR-simulated peer interactions. After each simulation, they rated their state dissociation and negative emotion. Violence exposure was positively associated with state dissociation. PTSS but not emotion dysregulation mediated effects of victimization on state dissociation. Results of multilevel modeling analyses suggested that participants who responded with more negative emotion across VR simulations were also more likely to seek relief by dissociating. These findings provide experimental support to the longstanding theory that adolescents with interpersonal violence exposure dissociate in response to negative emotion elicited from age-typical social challenges
Neutron Star Low-Mass X-Ray Binaries In And Out Of Focus: Nustar Stray Light
No full textNeutron star low-mass X-ray binaries (NS LMXBs) provide crucial insights into the physics of accretion under extreme gravity. In this dissertation, we explore the capabilities of NuSTAR’s stray light (SL) observations to supplement, and in some cases, surpass focused data in spectral studies of bright LMXBs. Utilizing the use of SL datasets, we perform detailed spectral analyses of two Z sources: GX 340+0 and Sco X-1.
For GX 340+0, we compare 7 focused and 25 SL observations across multiple spectral states, demonstrating that SL data significantly expand temporal coverage and allow for the detection of long-term spectral evolution not evident in focused observations alone. Continuum modeling with double thermal components, along with relativistic reflection modeling using the {\sc relxillNS} framework, enables constraints on NS surface and disk temperatures, disk inclination and ionization.
For Sco X-1, we present the first spectral analysis using an intentional SL observation. The dataset captures the source in the flaring branch (FB) and it is modeled with thermal Comptonization. Reflection analysis shows a disk inclination consistent with previous X-ray and radio studies. This work validates the high precision spectra of intentional SL data and underscores its potential in extending exposure time for extremely bright sources limited by telemetry constraints in focused observations.
Together, these studies demonstrate that properly reduced NuSTAR SL observations offer a powerful tool for high-energy astrophysics. This dissertation establishes a framework for SL data analysis and highlights its value for future missions aiming to maximize science return without additional observing time
Essays On The Drivers Of Strategic Alliances
No full textThis dissertation consists of two essays investigating the factors that influence the formation of strategic alliances. The first essay explores how penalties for corporate misconduct affect firms’ propensity to engage in strategic alliances. The findings indicate that firms increase their participation in strategic alliances following the imposition of misconduct penalties. Specifically, the likelihood of firms entering at least one alliance in the subsequent year increases from 5% to nearly 18% after a penalty. The positive correlation holds consistently across different measures of strategic alliances and corporate misconduct, the uses of instrumental variables, two quasi-natural experiments, Heckman selection and Heckman IV models, as well as the inclusion of various internal and external factors and alternative sample-matching methods. Notably, the positive association between corporate misconduct and strategic alliances is more pronounced for firms with high corporate social responsibility (CSR) ratings, suggesting that reputational concerns may drive this behavior. Additionally, while the market tends to react negatively to penalized firms, alliance partners of these firms experience positive market reactions during the announcement period, implying that these partners may secure more favorable terms in such alliances.The second essay examines the impact of climate policy uncertainty (CPU) on the formation of climate-related strategic alliances. This study utilizes data on more than 28,000 strategic alliances formed by publicly traded firms from 1990 to 2023 and employs a large language model (LLM) to classify whether each alliance is related to climate issues. The analysis reveals that CPU is positively associated with firms forming climate-related strategic alliances. This positive association is more pronounced among firms in carbon-intensive industries and those with greater exposure to climate risk. It is also stronger for firms with high CSR scores, especially when the CSR related to environmental responsibility is high. An analysis of cumulative abnormal returns (CAR) around the announcement of climate-related alliances shows that shareholders respond positively, suggesting these alliances create value for shareholders. Overall, this research provides evidence that strategic alliances can act as a tool for hedging risks associated with climate policy uncertainty
Data Sharing-Aware Task Allocation Algorithms In Edge Computing Systems
No full textEdge computing allows end-user devices to offload heavy computation to nearby edge servers for reduced latency, maximized profit, and/or minimized energy consumption. Data dependent tasks that analyze locally acquired sensing data are one of the most common candidates for task offloading in edge computing. Thus, the total latency and network loadare affected by the total amount of data transferred from end-user devices to the selected edge servers. Most existing solutions for task allocation in edge computing do not consider that some user tasks may operate on the same data items. Making the task allocation algorithm aware of the existing data sharing characteristics of tasks can help reduce the network load at a negligible profit loss by allocating more tasks sharing data on the same server.
In this dissertation, we formulate the data sharing-aware task allocation problem that makes decisions on task allocation for maximized profit and minimized network load by considering the data-sharing characteristics of tasks. In addition, because the problem is NP-hard, we design an offline algorithm called DSTA, which finds a close to optimal solution to the problem in polynomial time. We analyze the performance of our algorithm against a state-of-the-art baseline that only maximizes profit. Our analysis shows that DSTA leads to about eight times lower data load on the network while being within 1.03 times of the total profit on average compared to the baseline. In addition, we introduce the Online Data Sharing-aware Task Allocation (ODSTA) problem and design online algorithms for task allocation in edge computing that take into account the sharing of data among the tasks offloaded to the same server. We perform an extensive performance analysis by comparing our proposed data sharing-aware online algorithms with several baseline online sharing-oblivious algorithms. The results show that our algorithms are able to reduce the amount of data transferred in the network by 30.2% to 92.8% and the number of utilized servers by 1% to 82.8% compared to the sharing-oblivious baseline algorithms.
We also augment these online algorithms with a local search phase that iteratively attempts to improve the solutions obtained by our data sharing-aware algorithms by exploring the neighborhood of the current solution and making minor modifications. Our extensive experimental performance analysis shows that the algorithms augmented with local searchreduce the number of utilized servers by 9.1% to 66.7% compared to the data sharing-aware online algorithms at the expense of a small increase in the amount of data transferred in the network and a small increase in execution time. We provide a summary of the findings that can be used as a guideline for choosing a specific algorithm for a given practical scenario characterized by the tasks’ CPU demand and their data sharing characteristics
Examining The Gap In The K-12 Superintendency And African American Women In Michigan
No full textAfrican American women remain underrepresented in K-12 Superintendency roles across the United States, particularly in Michigan. Despite awareness being made on gender and racial disparities in educational leadership, limited research addresses the unique intersection of race, gender, and class affecting African American women’s experiences as K-12 educational leaders. This study addresses the systemic and structural barriers and supports that African American women face while pursuing and or serving in the K-12 Superintendency in Michigan. Grounded in Patricia Hill Collins’ (1990) Black Feminist Thought, this research uses the theory of intersectionality to understand the lived experiences of African American women as central to comprehending how power operates in education. Black Feminist Thought affirms that the lived experiences of African American women are valid forms of knowledge and resistance. Using qualitative, Black feminist methodology, this study centers the voices of African American K-12 Superintendents who have had to navigate many barriers, including the board of education, misconceptions of identity, and navigating complex social dynamics. Supportive sub-theme for these barriers includes negative stereotypes such as being ‘angry’ or ‘a bitch’, navigating predominantly White districts, proving yourself, the role itself, the search firm, White male counterparts with less education, better salaries with better benefits, the ceiling, and doing the work. Despite these barriers, the intersection also revealed a consistent pattern of support and aids, including having a support system with multiple components, mentorship, personal networking, being grounded in faith and prayer. Supportive sub-themes for these supports include recognizing that no one can do this job alone, having a supportive husband, staying connected, remaining relevant, avoiding feelings of stagnation, and expanding your exposure beyond your geographical location. These barriers and supports highlight the complex navigation required by African American women in educational leadership. The findings of this research underscore the deep-rooted structural biases and resistance to systemic change within education. By centering the voices of African American women K-12 Superintendents, this study contributes to the broader discourse on equity in educational leadership and highlights the urgent need for reform that addresses both racial and gender disparities embedded in school district practices across the United States
Under the Influence: New York’s Crisis of Addiction, Exploitation, and Drug Policy within Depression-Era Films
No full textDuring the 1930s, New York City stood at the center of media innovation and cultural influence. It was also the center of the continuing opioid epidemic and a pivotal site for the reception and promotion of addiction films. This article argues that Depression-era films, The Struggle (1931), Narcotic (1933), and Assassin of Youth (1938), reflected economic, political, and moral anxieties surrounding drug abuse. Using National Board of Review records, studio pressbooks, and contemporary periodicals, this study examines how cinematic portrayals of addiction influenced ideologies, criminalized users, and deepened social stigma
Fundamental Understanding And Designing Of Nickel And Cobalt Free Cathodes For Lithium-Ion Batteries
No full textDespite 30 years of active research in the field of Li-ion battery chemistry, the current energy demands attracted materials researchers, engineers, and chemists to develop new battery materials or redox mechanisms with high capacity and high energy density properties. In addition to fundamental issues in chemical design, raw materials scarcity and geopolitical issues are driving the shift away from critical raw materials such as nickel (Ni) and cobalt (Co) elements. Current state-of-the-art Li-ion batteries are reaching their theoretical limit with respect to their capacity, a property largely limited by cathode materials that so far relied solely on cationic-redox of transition-metal ions (e.g., M3+/4+ in LiMO2 where M is Co, Ni, and Mn) for driving electrochemical reactions. Recently, the introduction of new anion-redox (O2-/On-, n\u3c 2) cathode materials can lead to a doubling of capacity by accommodating multielectron (\u3e 1 e- or Li+ transfer per formula unit) redox chemistries that gained research interest. However, current anion-redox cathode materials based on Li-rich layered oxides (represented by the formula Li1+xM1-xO2 where M is Co, Ni, and Mn) suffer from voltage fade, large hysteresis, and sluggish kinetics, which originate mysteriously from the anionic redox activity of oxygen ligand itself. It is proven that the covalent interaction (tightness between metal – ligand bond) between transition metal – oxygen ligand in traditional cathode materials (LiCoO2, LiNixMnyCozO2, LiFePO4) needs to be altered to take advantage of anion redox chemistry. Here, in this dissertation work, an alternative approach of introducing improved metal – ligand covalency is presented by utilizing less electronegative chalcogen ligands (Sulfur (S), Selenium (Se) in the cathode structural framework where the metal d-band penetration into ligand p-band thereby utilizing mixed anionic and cationic redox chemistry. The experimental insights provide a significant design approach that will accelerate the search for prospective Ni and Co free chalcogen based cathodes in the pursuit of next generation energy storage materials. Tuning covalency by Ni and Co free metals and highly reversible chalcogen ligands (S, Se) led to address broader scientific impact: (i) eliminating the reliance on Ni and Co-based cathodes; (ii) high lithium storage capacity in liquid and solid-state systems; (iii) fast charging capability without crystal structure degradation; and (iv) improving thermal safety by eliminating detrimental O2 release. In summary, the dissertation research addresses the technological bottleneck in the field of anion redox cathode materials through fundamental materials chemistry, synchrotron spectroscopy, imaging, and electronic structure calculations. The presented ideas and strategies through this dissertation work will cover a broad spectrum of engineering principles, solid-state materials chemistry, and electronic structure for addressing one of the critical research problems in renewable energy materials space
Communication Interventions for Families with Parental Cancer with Dependents: Findings from a Scoping Review
Full text linkBackground: Since 2019, invasive cancer diagnoses in people younger than 50-years-old have increased by 12.8%, which impacts people of child-bearing age. Currently, interventions in families of parents with cancer are focused primarily on the parent with cancer communicating with their dependents about the initial cancer diagnosis or at end-of-life through in-person interventions. Limited web-based interventions have been developed to increase communication across all family members (e.g., parents with cancer with coparents; children with their parents) about communicating the impact of cancer on the individual’s and family’s well-being cross the cancer trajectory, a key gap to improved outcomes in this population.
Aims: This review provides a comprehensive summary of published literature on the types of family communication interventions when a parent has cancer with dependents and to identify and analyze the knowledge gaps regarding family communication interventions in this population.
Methods: A comprehensive informationist-assisted search was done with seven databases. Two reviewers independently performed title/abstract and full-text reviews within Rayyan software system. Extraction was performed by two reviewers.
Results: The 35 articles included investigated 24 different interventions. Most articles were published by European teams (45%). Fourteen articles (40%) evaluated interventions that included the entire family, with seven (20%) reported family theories and three (9%) delivered via the web. Most articles focused on the parent’s with cancer and the dependent’s outcomes (31%) and most interventions were aimed to increase communication at end-of-life (43%) or at early diagnosis (32%) with dependents in the breast cancer population.
Linking Evidence to Action: In-person communication interventions have been developed to communicate with dependents about an early or terminal cancer diagnosis and the impact of the intervention on parent’s with cancer and children’s outcomes. No web-based interventions have been published that focus on the entire family, include family-level outcomes, or completed dyadic analysis across the family on the family-level outcomes to determine relationships. Web-based interventions are needed to address communication challenges for all family members affected by a cancer diagnosis, while supporting equitable access to such interventions
“Breaking the Fairy Tale”: Narrative Transgression in the Video Game Cinders
No full textThis article explores how the mechanics of game play interact with the narrative expectations of the fairy-tale genre in the 2012 video game Cinders, from indie studio Moa Cube. The narrative of Cinderella retold in the game centers the title character’s agency and transgression as players move through the familiar tale and make choices about how Cinders should act and react. I argue that the game’s focus on agency as a theme is mirrored in its structure as a visual novel that calls on players to make the fairy tale their own and in the game mechanics that give players choices