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Utilizing a Hybrid Apprach to Link Maternal and Neonatal Records
No full textLinkage of independent datasets allows comprehensive and robust analysis. This study aims to utilize a hybrid strategy to link maternal records with neonatal data with an overarching goal of investigating correlates of adverse birth outcomes.
To link 126,757 records from Nevada Medicaid with 249,181 maternal records from Birth Registry, a hybrid linkage approach was utilized. Data normalization was first performed for the standardization of linkage keys. First, a deterministic approach was used to link these records using a unique identifier followed by a fuzzy or probabilistic algorithm using a set of block variables. These block variables included date of birth, gender, zip code of birth place, and first/last name of the neonates. For this matching, a minimum threshold of 40 out of 50 was deemed appropriate (10 points for each block variable). After the linkage, data were de-identified to adhere with the ethical guidelines. All linkage procedures were performed via PROC SQL functionality (left join) in SAS 9.4 software.
In the first deterministic phase, 63% of the records (n= 80,107 of 126,757 records) were linked (true positives). From remaining 46,650 records, 26,095 were matched through the probabilistic linkage which sum up to 106,202 records in total. Further, 538 records were identified as false positives, which were removed from the dataset. This results in an 83.4% linkage efficiency with a total number of 105,664 linked records.
The hybrid linkage offers a viable strategy to improve the linkage efficiency and numerous benefits to population-based research.https://oasis.library.unlv.edu/durep_posters/1229/thumbnail.jp
Examining the Effects of Food Insecurity and Socioeconomic Status on Breastfeeding Duration Among Latina Mothers in Las Vegas
No full textBackground: This study aims to investigate breastfeeding duration among Latina mothers in Clark County. We hypothesize that Latina mothers who experience significant health disparities, including low food security and limited economic resources, are likely to have shorter breastfeeding durations.
Methods: This study employed a cross-sectional design. The preliminary sample included 54 mothers who met the following inclusion criteria: aged 18 or older, self-identifying as Latina, having at least one child under 5 years old, and residing within Clark County. The survey included questions related to experiencing food insecurity, socioeconomic factors, and breastfeeding duration. Data analysis was performed using STATA 17 and applying Fisher\u27s exact test to studied variables.
Results: This preliminary analysis found no statistically significant correlation between social inequality factors, such as concerns regarding food shortages, enrollment in food assistance programs, and income level, and breastfeeding duration. However, specific trends were observed. Notably, mothers who participated in food assistance programs, experienced food shortages within the last year, or had an annual income under $30,000 demonstrated a higher likelihood of breastfeeding for less than 24 weeks.
Conclusions: Initiative needs to be taken to increase funding and accessibility for food assistance programs. Efforts should be made to integrate culturally sensitive breastfeeding education and accessible lactation support within community clinics, along with offering subsidized breastfeeding supplies.https://oasis.library.unlv.edu/durep_posters/1238/thumbnail.jp
Alteration of Peripheral Cytokines in Alzheimer’s Disease
No full textAlzheimer’s disease (AD) is a progressive neurodegenerative disease with the clinical symptoms of gradual cognitive decline and memory loss. Biologically, abnormal accumulation of Aβ (Aβ) plaque and tau tangles in the brain are the core pathological hallmarks in AD. Although inflammatory response is not specific to AD, emerging evidence suggests that the disrupted innate immune system within the central nervous system, particularly microglial activation, might act as the bridge linking Aβ aggregation to pathological phosphorylation and aggregation of tau. The inflammatory response was suggested to initially have a neuroprotective role of attempting to clear Aβ plaques, and then become neurotoxic in a chronic inflammatory state upon failure to clear Aβ. Cytokines, as a family of small proteins acting as the chemical messengers in the immune system, are the potential biomarker candidates reflecting the changes in the immune system. Many studies have evaluated the concentration difference of cytokines between patients in the AD continuum and controls to examine neuroinflammation in AD, however, substantial discrepancies were observed between studies. Considering the dual role of inflammation in AD and the competing and synergistic effects of numerous cytokines in the body, we analyzed the cytokine data from human participants and APP mice with the hypothesis that 1) cytokine concentrations change in a nonlinear fashion with disease progression and 2) the interaction between cytokines is disrupted in AD. We found that multiple cytokines had discrepant association with brain amyloid burden before and after brain amyloid reaching pathological level, and most of them were closely relevant to hematopoietic function. In addition, the correlations between cytokines were substantially different between amyloid positive participants (A+) and cognitively unimpaired amyloid negative participants (CU-). Pairwise correlation analysis between cytokines showed that the cytokine pairs having strong correlations in CU- were more likely to have weaker correlations in A+ group, such a change was consistently observed in the comparison between APP mice and wild-type mice. A discordance score was defined to characterize the less concordant cytokine levels in the disease population at the individual level. Compared to cytokine concentration, the discordance score had better discriminative power in separating A+ participants from CU- participants. Our findings suggest that the immunotherapy targeting at hematopoietic function might be beneficial for delaying AD progression, although the effect might depend on the disease stage and the signaling pathway at the molecular level remains to be identified. Furthermore, compared to the concentration of each cytokine, the interaction between peripheral cytokines might be a more promising metric to characterize altered immune responses in AD
A Culturally Responsive Approach to Mindfulness and Mental Health Informal Education
No full textThe qualitative study examined the mental health aspects of marginalized elementary school students in addition to constructing and implementing a culturally responsive and sustaining mindfulness program to observe if there were improvements regarding emotional regulation and awareness. To achieve this, I constructed a culturally responsive and sustaining mindfulness program, implemented this program, and studied the responses from students. The research questions that fueled this study include: (1) What types of negative emotions do marginalized elementary students experience? What is the root cause for marginalized students experiencing negative emotions during their elementary school years? (2) How can incorporating mindfulness techniques embedded with culturally responsive and sustaining pedagogies aid marginalized students in overcoming negative emotions that they experience in elementary school? (3) How can culturally responsive mindfulness programs be sustainable and transformative for marginalized students who frequently encounter negative emotions? (4) What challenges and difficulties are there in developing and implementing such a program? How do I search for and implement solutions? The results from this study showed that the majority of marginalized students consistently felt negative emotions at school, including overwhelming stress caused by academic pressure, nervousness due to previous trauma related to bullying, and anger due to disliking school for numerous reasons. Additionally, creating such a program that incorporated mindfulness and culturally responsive and sustaining pedagogies positively impacted students, equipping them with critical reflection skills to discover new techniques to help them overcome negative emotions and build resilience. The main challenge I faced as the researcher when constructing and implementing such a program was ensuring the program incorporated effective and meaningful activities that embraced all student cultures
Real-Time Predictive Analytics for Healthcare Monitoring and Terrain Classification Using Data Streaming and Online Learning
No full textThis thesis develops a scalable, real-time predictive framework aimed at improving outcomes in healthcare monitoring and gait classification. Specifically, it addresses two primary applications: early detection of cardiovascular events, myocardial infarction (MI) and arrhythmia, through continuous analysis of ECG data streams; and adaptive terrain classification from gait data. Utilizing data streaming technologies such as Apache Kafka and Apache Spark, coupled with machine learning models, this framework enables near real-time and precise predictions from high-throughput, real-time data. Furthermore, the integration of online learning frameworks, including the River API and TensorFlow I/O, allows for continuous model adaptation, enhancing the system’s responsiveness and predictive accuracy in dynamic, evolving environments.In the healthcare domain, a heart attack and arrhythmia prediction pipeline is established using logistic regression, multilayer perception (MLP), and LSTM-based models to assess real-time ECG data for early indications of cardiovascular risk. Findings demonstrate that the online learning models incorporated into the system outperformed static models by continuously adapting to new data patterns, maintaining high levels of predictive relevance. In the context of terrain classification, machine learning models such as Random Forest, XGBoost, BiLSTMs, and MLPs are applied to gait data from foot-mounted inertial measurement units (IMUs) across various surfaces. Adaptive real-time classification is achieved through online learning, allowing the system to dynamically adjust as new terrain data is received. A comparative analysis between River API-based and TensorFlow-based models reveals trade-offs between high static accuracy and the flexibility of incremental learning, suggesting that each approach has unique advantages depending on the stability or variability of the data environment. Results from the real-time health monitoring and gait classification applications underscore the efficacy of combining data streaming platforms with adaptive learning frameworks. The study indicates that while deep learning models excel in stable environments requiring static accuracy, online learning frameworks provide superior adaptability, making them well-suited for dynamic, continuously evolving data contexts. Furthermore, the research addresses challenges such as class adaptation, dynamic data scaling, and missing value management in real-time streaming applications, contributing solutions to improve efficiency. This research advances the field of real-time predictive analytics, offering robust, adaptive system architecture that supports proactive healthcare monitoring and terrain classification for enhanced safety and functionality in assistive technologies and autonomous systems
Internationalization Strategies of Asian Hotel Companies – A Knowledge-Integration Perspective
No full textThis study aims to contribute to understanding sustainable internationalization of Asian Hotel Companies (AHCs) by adopting a knowledge-integration approach. The focus is on developing competence models for long-term success, specifically from a knowledge-integration perspective.
A mixed-method approach comprising both qualitative and quantitative studies was implemented. Initially, a series of interviews with 16 top hotel executives (and industry experts) were conducted to gain an in-depth understanding of the issues relating to the internationalization of AHCs. The transcribed interviews were used to develop themes from which critical variables related to knowledge management and integration of AHCs were generated. Hypotheses were then tested based on these variables. In the next stage, a self-administered survey was conducted with 176 respondents. The cleaned dataset, comprising a sample size of 114, was subsequently analyzed to test the direct, mediated, and moderated relationships among variables using R-Studio and SPSS.
The findings of this study have practical implications for the internationalization strategies of AHCs. They reveal that successful strategies significantly hinge on knowledge integration. Entrepreneurial competencies serve as a crucial mediator, enhancing the ability to strategically leverage knowledge from network resources and market opportunities to achieve superior performance following international growth. Absorptive capacity moderates, conditionally optimizing how AHCs can utilize and effectively integrate external knowledge and information. This empirical evidence suggests that AHCs can pursue an asset-light path in their international growth trajectory, provided that knowledge management and integration practices are implemented to promote operational agility and sustainable expansion.
The study provides empirical evidence that supports the potential for AHCs to pursue an asset-light international growth strategy. This approach is feasible if aspects of knowledge management are widely adopted and knowledge integration practices are implemented, promoting operational agility and sustainable international expansion. Given that AHCs are latecomers in the international arena, the knowledge integration perspective is crucial to accelerating their growth plans in more developed regions. This study underscores the importance of knowledge management and integration in achieving competitive advantage and sustainable internationalization for AHCs
Corporate-Led Financialization on the Farmland, Land Crisis, and Farmers’ Experience in the Sugar Industry in Dwangwa, Malawi
No full textThis study explored the experiences of independent sugar cane farmers, families, and communities in the corporate-led sugar industry in Dwangwa, Malawi. I collected data from 50–60-minute semi-structured interviews, observations, and interactions from 30 independent cane growers, families, and communities in Dwangwa, the study findings were also based on textual data about local and national business and political elites and corporate investors in Malawi’s sugar industry. Data collection occurred from May to August 2023 in Malawi. The study found that independent cane growers and families identified job creation and access to the sugar market as their topmost positive experiences due to corporate-led sugar production and processing in Dwangwa. However, study participants lamented the lack of transparency during their market and social transactions with Illovo Sugar Group, Illovo Sugar Malawi Limited (ISML), and their partners like Illovo Accredited Cane Growers Associations (IACGAs). For example, participants reported that IACGAs did not disburse proceeds from participants’ sugar sales and deliver farm services to farmers on time. Also, respondents blamed IACGAs for using poor farmers as loan collateral at the bank, overrating and overvaluing farm inputs they rented to independent cane farmers. The study participants also reported that ISML did not allow farmers to be present at the market physically and that (out of their sugar cane), farmers were paid for sugar only by the ISML. So, the lack of transparency by foreign investors appears to reinforce class and racial inequalities, while maximizing their profits by exploiting the labor of the poor independent cane farmers, families, and communities in Dwangwa. Ultimately, this paper does not view the financialization of farmland as a rural development opportunity nor the neocolonialism of the Global South. But rather as an intensification of capitalist globalization by neoliberal agriculture
Effect of Epistemic Cognition and Self-Regulation on the Evaluation of Online Information
No full textWhile research has shown that epistemic cognition plays an important role in self-regulation, the way in which it does so in online contexts needs further research. The objective of this dissertation was to examine the relationship between Internet-specific epistemic cognition and Internet-specific self-regulated learning, and to use a mixed-methods approach in order to expand upon the way learners undergo the evaluation of information in online spaces beyond the traditional method of only using self-report measures and other common quantitative techniques. Using an explanatory sequential mixed-methods design, Phase 1 (N = 117) used quantitative methods to first look at the relationship between epistemic cognition and self-regulated learning (SRL), using both the Internet-specific epistemological questionnaire (ISEQ) and a self-regulated learning questionnaire. Then a Pearson’s test of correlation was used to examine any indication of a relationship between these self-report measures. Using qualitative methods, Phase 2 (n = 12) used an online text, think-aloud protocols, and semi-structured interviews to better determine how epistemic cognition and self-regulated learning impact information evaluation while on the Internet, particularly when information with discrepancies is present, as well as how these results differed from the self-report data. For their task participants read a text on supplement use for preventing and treating a cold, which had both accurate information as well as discrepancies. During this task they followed think-aloud protocols to record what they were doing and thinking during the task, and then semi-structured interviews were completed afterwards. This data was used to provide a different perspective into how participants use epistemic cognition and self- regulation during online information gathering and evaluation, as compared to the self-report measures in Phase 1
Carbon Dioxide Adsorption Capacities of Unmodified Biochar Derived From the Great Basin Desert Ecosystem
No full textClimate change and wildfires are two interconnected crises that present a great danger to the American southwest. Anthropogenic greenhouse gases including carbon dioxide have warmed the earth, creating droughts and altering weather patterns so that wildfires have increased in severity and intensity within the region. Wildfires in turn release stored carbon from biomass into the atmosphere, creating a dangerous feedback loop that destroys vast swaths of land in areas including the Great Basin Desert of northern Nevada and surrounding states. Fuel breaks offer a method to slow the spread of wildfires but are costly and generate large amounts of waste biomass material. This material can be transformed into biochar (BC), a porous carbonaceous material that sequesters carbon and can adsorb CO2 to assist in stopping climate change. In this thesis, four materials found in the Great Basin Desert (pinyon pine wood and needles, big sagebrush, and cheatgrass) were transformed into biochar at pyrolysis temperatures of 500 C, 600 C, and 700 C and studied for their materials characteristics. These biochars were then tested for their CO2 adsorption abilities via thermogravimetric analysis (TGA) and a column study. Materials characterizations found that cheatgrass biochar had an especially high BET surface area (428.73 m2/g at 700 C), while pinyon pine needle biochar had a high nitrogen content, which is linked to increased material basicity. Additionally, Fourier transform infrared spectroscopy analysis indicated a decrease in the acidic oxygen functional group O-H bend (carboxylic acid) for all materials as pyrolysis temperature increased. TGA testing showed that all materials had similar adsorption properties at the same pyrolysis temperatures with adsorption increasing as temperature increased, while column studies measured lower adsorption values but suggested that cheatgrass BC had a significantly higher adsorption than the other tested materials. These results indicate that physisorption through high surface area and chemisorption through high basicity are both strong influencing factors to CO2 adsorption. Additionally, this study shows that higher pyrolysis temperatures are beneficial to adsorption for these four materials, with cheatgrass pyrolyzed at 700 C having the highest adsorption value of 73.3 mg CO2/g BC via TGA testing. This study can be expanded in the future to include a greater range of pyrolysis temperatures and times, an expanded column study, and adsorption testing under different gas conditions
Electrical Contact to MoS2 for Sensitive Capacitance Measurements
No full textWhen electrons confined to two dimensions are subjected to a low temperature and high magnetic field environment, exact quantization of macroscopic material properties can occur, known as the integer (IQHE) and fractional (FQHE) quantum Hall effects. Important experimental platforms utilized to investigate the IQHE and FQHE are graphene-based van der Waals (vdW) heterostructures due to their high carrier mobility and easy access to low carrier density regimes. These heterostructures are limited in their scope however as graphene does not possess an energy band gap or strong spin-orbit coupling, two properties that lead to unique effects on the IQHE and FQHE. This is in stark contrast with other 2D materials such as the semiconducting transition metal dichalcogenides (TMDs) which contain both necessary ingredients. In this thesis, baseline measurements of penetration field capacitance (Cp) are confirmed on a monolayer graphene (MLG) vdW heterostructure at T = 3 K and B = 2 T, showing the ability to resolve features of electronic incompressibility. Cp and transport measurements are also presented on a few-layer MoS2 heterostructure, allowing a direct comparison between the two measurement techniques to resolve the conduction band edge of MoS2. Due to Schottky barrier formation between few-layer graphene contacts and MoS2, the resulting contact is non-ohmic, limiting measurements of Cp and transport to above 200 K. Concluding, a semimetallic bismuth contact method is investigated on a few-layer MoS2 sample, achieving multiple ohmic contacts with extracted Schottky barrier heights of 30 meV and -15 meV. The ohmic contact results in linear IV characteristics and large on-off ratios of 107 down to T = 3 K at low carrier densities n \u3c 3 10−12 cm−2. This work sets a foundation for sensitive capacitance measurements of the interesting class of TMDs in the low carrier density regime