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Did California\u27s Mental Health Services Act Improve Mental Health? Evidence from Self-Reported Data
Get PDFThis analysis evaluates the impact of California’s Mental Health Services Act (MHSA), which was implemented in 2006 to increase access and improve quality of mental health care for Californians. Difference-in-differences analyses were applied to evaluate the impact of the MHSA on the number of poor mental health days in the past month (PMHDs) that survey respondents had self-reported, relative to a control group with similar pre-policy trends. Using survey data from the Behavioral Risk Factor Surveillance System (BRFSS), this study found that the MHSA’s full implementation is associated with California respondents reporting 0.118 fewer poor mental health days in the past month, on average, than respondents from the control group. An additional difference-in-differences model uses a binary indicator as the dependent variable – marking respondents with a 1 if they reported 7 or more PMHDs, and a 0 if they reported less than 7 PMHDs. This additional model finds that the MHSA’s full implementation is associated with a 1.2 percentage point lower probability of the average California respondent reporting 7 or more poor mental health days in the last month, on average, than similar respondents from the control group. These results suggest that the MHSA’s implementation is associated with improvements in day-to-day mental health for both the general population and those with established mental health struggles. Further research could clarify potential confounding effects regarding those with established poor mental health
Effect of Cigarette Smoke Extract and Nutrient Deficiency on Energy Metabolism and Biosynthesis: An in Vitro Intervertebral Disc Explant Culture Study
No full textLow back pain consistently ranks among the leading causes of disability worldwide, with degenerative changes in spinal intervertebral discs (IVDs) recognized as a key contributor. Degeneration arises from the disruption of mechanical and biological cues within the disc’s cartilaginous tissue, often exacerbated by aging or injury. In recent decades, cigarette smoking has also been identified as a significant risk factor, as IVD degeneration is more prevalent among individuals with a history of smoking. Smoke inhalation is thought to promote degeneration both directly, by exposing cells to water-soluble toxic chemicals in smoke; and indirectly, through nutrient deficiency resulting from vasoconstriction and carboxyhemoglobin saturation. Both effects may alter disc cellular energy metabolism, which is crucial for cell survival and proliferation, thereby impacting the biosynthesis of IVD extracellular matrix (ECM) components. However, no studies have delineated the direct and indirect effects of smoking through quantitative comparison or examined the regionally heterogeneous impacts on IVD tissue. The objective of this work was to establish an in vitro IVD explant culture model using Sprague Dawley rats to investigate the effects of cigarette smoke extract (CSE) and nutrient deprivation on cellular energy metabolism and ECM biosynthesis in different disc regions. It was hypothesized that both the direct and indirect effects of cigarette smoking impair IVD cellular energy metabolism and ECM biosynthesis, with heterogeneous responses across nucleus pulposus (NP), annulus fibrosus (AF), and cartilage endplate (CEP) regions. To test this hypothesis, two aims were pursued: (1) cellular metabolic activity assessment, using a biochemical analyzer to quantify rates of glucose consumption, lactate production, and their ratio under physiological, CSE-treated, and nutrient-deficient culture conditions in each IVD region; and (2) biosynthetic activity assessment, using metabolic labeling via copper-free click chemistry to measure glycosaminoglycan (GAG) and collagen content in whole-disc samples cultured under the same conditions. In addition, a finite element model incorporating a reaction-diffusion framework was preliminarily developed to investigate the effects of CSE exposure and nutrient deprivation on three-dimensional nutrient gradients and ATP production within the IVD. Cellular metabolic assessment revealed that, in both CSE-treated and nutrient-deprived discs, energy metabolism was primarily driven by glycolysis, indicating a disrupted metabolic profile. Regionally, CEP explants demonstrated greater resistance to metabolic disruption than either NP or AF. Quantitative fluorescence intensity measurements using a plate reader revealed declines in newly synthesized GAG and collagen, which was further supported by fluorescence imaging of the explants. Computational modeling supported these findings by illustrating disruptions in nutrient gradients and ATP production within the disc under both CSE treatment and nutrient deprivation, with the most pronounced reduction observed in the CEP region. Together, these results indicate that both CSE treatment and nutrient deficiency have a cumulative impact on IVD cellular metabolic activity. This study provides new insight into the mechanisms by which cigarette smoking contributes to IVD degeneration and lays groundwork for developing targeted therapies aimed at mitigating its onset and progression
Advancing Multi-Physics Modeling for Microwave Heating: Application in Micro-Reactor Design and Optimization
No full textMicroreactors are a type of small-scale chemical reactors for achieving reduced volume, improved product selectivity and higher reaction rate. It allows precise temperature control, which is crucial for sensitive chemical processes. Microreactors can be employed as key components of conducting small-scale reactions with improved reactor configuration and process efficiency. It is important to identify a localized and precise heating mechanism to trigger and control the corresponding chemical reactions.
In fact, microwave heating has gathered significant attention in recent years due to its ability to deliver efficient, rapid, and localized heating, which can accelerate reaction rates and enhances the reaction selectivity. This ability makes microwave heated micro-reactors a promising product for industrial applications with fine control of temperature field, reaction rate, and precise chemical synthesis.
Over the years, multi-physics simulations have been adopted to understand the complexities of microwave heating, optimize the microreactor design, and predict the temperature distributions and reaction rates. However, in most of the established multi-physics models, energy exchange due to chemical reactions have not been considered. Meanwhile, the reactants’ material properties such as permittivity and thermal conductivity varies as the reaction progresses. Such material property variation may directly influence the efficiency of microwave heating and are worth investigating.
To address these shortcomings, an extension to the current multi-physics model is proposed through COMSOL by incorporating energy dynamics during chemical reactions and the variation of material properties as a function of temperature and mass content. The extended model accounts for the heat exchange during the chemical reaction, the temperature sensitive material properties, and the variation of the reactant mass ratio during the reaction progresses. A solid phase reaction of limestone decomposition is adopted for model validation purposes. The roles of energy dynamics, material properties variation, microwave characteristics and microreactor geometry characteristics to the temperature distribution of the microreactor and the efficiency of the microwave heating are investigated.
Even though future systematic studies needs to be conduct and the results need to be validated, this work established a framework for future developments in microreactor design under microwave heating
Secure Control and Trust Evaluation Framework for Autonomous Transportation Systems
No full textThis dissertation advances the cybersecurity of hybrid tracked vehicles (HTVs) and ship power systems (SPSs) by developing innovative cyber-attack models and corresponding defence frameworks. First, we formulate stealthy false-data-injection attacks (FDIAs) on HTV energy-management systems as a partially observable Markov decision process (POMDP) solved via deep reinforcement learning. A novel sniffing-based reward function guides the attacker to covertly degrade battery capacity and energy efficiency, which we evaluate using custom stealth–impact metrics and a sliding-window anomaly detector (Isolation Forest with Dynamic Time Warping). Additionally, we model sophisticated control-layer attacks in HTVs, including reinforcement-learning-optimised replay attacks and denial-of-service (DoS) attacks targeting generator-speed sensors to disrupt the energy supply. These scenarios, implemented in MATLAB/Simulink, establish challenging benchmarks for developing resilient countermeasures.
To detect and mitigate such threats, we propose a dynamic trust-evaluation scheme grounded in Zero Trust Architecture principles. This framework fuses current and historical sensor behaviour in a multi-attribute model to identify anomalies under stealthy replay and DoS attack vectors in real time. Experimental validation on HTV systems demonstrates a detection accuracy of 96.35% with only 3.2ms latency. We further introduce hard- and soft-trust modes to quantify the trade-off between detection precision and responsiveness.
Finally, we extend our cybersecurity approach to medium-voltage DC ship power systems by designing a federated-learning-based anomaly-detection framework. Leveraging distributed controller data and real-time digital twins, this method detects and localises compromised agents via reconstruction-error analysis. Simulation results using OPAL-RT hardware-in-the-loop test data confirm its effectiveness in detecting the investigated cyberattacks. Collectively, these contributions provide a comprehensive security blueprint for mission-critical land and naval cyber-physical systems, significantly enhancing the resilience of defence and autonomous-vehicle platforms against advanced cyber threats
The Shame of (Be)Longing in Jamaica Kincaid\u27s Lucy
Get PDFThis thesis examines the role of shame in Kincaid\u27s Lucy. Separated into four separate sections, the thesis moves through Lucy’s relationship with her boss, Mariah, her Antiguan mother, and the shame that is identified at the end of the novel. In the introduction, I identify the passage that frames the novel around shame. I then identify my thesis, which centers around Lucy’s shame and her inability and refusal to situate herself with neither Mariah nor her mother’s expectations. The second section of the thesis revolves around Mariah and the form of feminism that skews her perception and expectations of Lucy. Critics such as Suzanne Roszak and Jennnifer Nichols are incorporated in this section. The third section discusses Lucy’s mother in Antigua and the colonial history that Lucy attaches to her. Her mother expects her to return to Antigua and engage with the colonial influences that Lucy aims to escape by leaving for the United States. Postcolonial scholar Leela Gandhi’s book, Postcolonial Theory: A Critical Introduction, is referenced within this section. Finally, the fourth section connects both Mariah and Lucy’s mother to the overarching shame and longing that Lucy expresses at the conclusion of the novel. This section highlights Lucy’s inability to coexist between expectations of Mariah’s feminism and her mother’s colonial culture. The shame at the end of the novel expresses Lucy’s knowledge that she cannot exist within these expectations without a form of personal sacrifice, but she longs to love and belong despite this. Lucy’s shame is defined primarily within the novel, but is partially informed by Tomkins’ Affect Imagery Consciousness: The Complete Edition. His definition includes the shame found within enjoyment, which manifests in the love Lucy possesses for both Mariah and her mother. Within the novel the development of Lucy’s shame is identified in passages of guilt, nostalgia, and anger after moments and reflections of love
Sensory Elements and Perceived Value in Cosmetics Packaging
Get PDFThis research looked at how different sensory features of packaging can affect the way Generation Z consumers feel about a product\u27s value. Focusing on a high-end sunscreen brand called Oasis Sunscreen Co., four packages were created with a unique sensory element. 53 college students were surveyed to see which package they preferred. The results showed that the visual aspects of the packaging were the most important, with over half of the participants choosing the visually appealing package as their favorite. Scented packaging also caught people\u27s attention, while features that involved touch were appreciated but not as influential. The study suggested that combining strong visuals with another sensory element could create the best impact. Overall, these findings indicated that engaging consumers\u27 senses is an effective way for brands to connect with Gen Z. By using sensory elements in their packaging, cosmetic companies could create memorable experiences that attract this generation, potentially leading to stronger brand loyalty and increased profits. This research encourages further investigation into the benefits of sensory packaging and highlights the importance for brands to adapt to the changing preferences of consumers
After Midnight: Analyzing Legacy Business Programs\u27 Potential to Capture Patron Perspectives Through a Case Study of Four Charleston, SC Nightlife Spaces
Get PDFWithin historic preservation, Legacy Business Programs (LBPs) are increasingly popular initiatives to support and celebrate businesses that have contributed to the history and culture of their communities and reached a certain operational age. LBPs are important to their communities and are part of a growing trend towards vernacular study and democratization within the preservation field. In particular, LBP application processes have the potential to document significant aspects of these important community businesses. Different LBP application questions can capture different types of business information from a range of perspectives. Within the movement towards greater inclusivity in historic preservation, understanding and documenting the aspects that patrons notice, interact with, and highlight about well-loved community businesses are important components of acknowledging and preserving the significance of these spaces. This research seeks to understand if the questions used in LBP applications are capable of capturing business attributes that patrons identify as important when publicly sharing their experiences. To achieve this goal, this thesis uses case studies of four Legacy Nightlife Businesses in Charleston, SC. Using common themes pulled from online reviews of the four businesses, this thesis compares these themes to the application questions used by LBPs across the country to establish a business’s legacy status. This comparison provides insight into the degree to which LBPs can capture the specific aspects of a business that are important to patrons. This research finds that one-third of the LBP questions analyzed do not capture any patron themes. Rather, many LBP application questions solicit information from a business owner perspective. This thesis provides insight into the LBPs and application questions that are effective at capturing patron perspectives, as well as the types of patron-identified business characteristics that are most captured by LBPs today. This thesis also makes recommendations for crafting LBP application questions that are more able to capture patron-identified business characteristics with the goal of centering community perspectives and supporting the movement towards a more democratic and inclusive preservation field
The Shift of Western Power in the Anglo-American Relationship as Examined through the Military Events of World War II
Get PDFHow did the authority within the Anglo-American Alliance begin to shift toward the American domination that ruled the second half of the twentieth century? By examining the events of World War II, this thesis restructures the typical timeline with which historians have approached the dynamic of authority in the Anglo-American Relationship. Many historians claim that America was the perceived senior partner by 1941; however, this thesis demonstrates that by examining things from a military lens, that date must change. The British continued to operate under the intention of maintaining their global authority through 1945 and even into 1946. The thesis utilizes the events of the Dieppe Raid, Operation Overlord, and Operation Market Garden, while also briefly discussing other military movements, such as Operation Torch and Operation Anvil, to illustrate the shift in three key vectors of authority: broader strategy, operational command, and force structure