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Dónde Está Mi Gente? Latinx/a/os in Rural Hispanic-Serving Institutions
No full textGiven the significant growth in the Latinx/a/o population in the United States, particularly in rural areas, there is a need for research that examines the experiences of Latinx/a/os currently enrolled in rural higher education. Existing scholarship on Latinx/a/os in higher education has primarily focused on their experiences within urban institutions, including current research on servingness. While most recent research on rural students has centered on white students, this qualitative study seeks to add to empirical research by exploring the experiences of Latinx/a/os attending rural higher education. Using community cultural wealth as a guiding framework, I explore rural Latinx/a/o students\u27 postsecondary experiences in the Pacific Northwest. My Chicana feminist and immigrant-scholar epistemological techniques guided the pl ticas, a culturally inclusive research methodology. Accordingly, the following research questions guide this study: How do Latinx/a/o students experience and navigate rural higher education? How do Latinx/a/os describe culturally validating experiences within rural HSIs and eHSIs? Study findings indicate two main themes. First, familial capital is cornerstone for rural Latina/os experiences and how they navigate rural higher education institutions. Second, federally funded college success programs, notably the College Assistance Migrant Program, TRIO Student Support Services, and National Science Foundation-funded STEM programs, are key programs that support rural Latina/os as they transition to and navigate rural higher education through culturally validating experiences. Study findings have the potential to expand our understanding of servingness within rural Hispanic-serving institutions from the lived experiences of currently enrolled students. Furthermore, it expands the collective understanding of the experiences of Latinx/a/os in rural higher education and rural HSIs by exploring students\u27 lived experiences from an asset-based perspective and bringing forth culturally validating experiences through empirical research
Dynamic Model of an Overhead Crane
No full textIn this thesis a novel spatial model of an overhead crane was developed. The model includes: bridge, trolley, driving and follower wheels for the bridge and trolley, drum, cable, and the payload. The model accounts for the winding/unwinding of the cable around the drum as the payload is raised/lowered. The cable and the payload were considered as rigid bodies with uniformly distributed mass. First, the kinematic equations of the model were developed by using constraint equations. Second, the dynamic equations were derived through use of Newton’s Laws. Developing the rotational dynamic equations required the determination of the angular momentum vectors of the rigid bodies as expressed with respect to an inertial frame. However, the orientations of the rigid bodies were described using Euler angles, which are neither absolute angular coordinates nor described with respect to an inertial frame. Hence, a novel derivation of the angular momentum vector with respect to an inertial frame in terms of Euler angles and local parameters was developed. In addition, a new approach for deriving the dynamic equilibrium torque of the drum was developed; this method used the constraints forces instead of the positions, velocities, and accelerations of the bodies. The motion of the system was simulated with bang-bang inputs and the results prove that the model is stable
Formation Potential of Disinfection Byproducts from Quaternary Ammonium Surfactants During Ozonation with Subsequent Chlor(am)ination
No full textQuaternary ammonium-based surfactants (QAS) are ubiquitous in daily life, found in products ranging from disinfectants and fabric softeners to food preservatives and personal care products. Their widespread use, especially during the COVID-19 pandemic due to their antimicrobial properties, has made them indispensable in modern hygiene and public health practices. However, their prevalence is not without concerns. When these compounds enter wastewater treatment plants, they are not fully degraded by the conventional treatment methods used, due to variations in their structural properties. As a result, QAS residues persist and accumulate in treated wastewater effluents, ultimately affecting water sources. These residues end up in water treatment plants where they are transformed into potentially harmful disinfection byproducts (DBPs) through methods such as ozonation and subsequent chlorination/chloramination.This necessitated a comprehensive investigation into the reaction of these compounds with common water treatment disinfectants including chlorine, monochloramine, and ozone. This study examined the formation potential of disinfection byproducts (DBPs) namely haloacetic acids (HAAs), haloacetonitriles (HANs), N-nitrosamines (NOAs), and trihalomethanes (THMs) from ten distinct quaternary ammonium-based surfactants (QAS) including allyltrimethyl ammonium chloride (ATMAC), benzalkonium chloride (BAC), benzethonium chloride (BTC), cetylpyridinium chloride monohydrate (CPC), Cetyltrimethylammonium chloride (CTMAC), diallyldimethyl ammonium chloride (DDAC), dodecyltrimethylammonium chloride (DTMA), didecyldimethylammonium chloride (DDEC), polydiallyldimethylammonium chloride solution (polyDADMAC), tetramethylammonium chloride (TMAC). These compounds were selected based on their prevalent use in commonly available consumer products and structural variations such as the presence or absence of a benzene ring, chain length, and saturation level of the carbon chains. They were prepared to a target concentration of 0.1 mM and subjected to simulated water treatment processes, including chlorination/chloramination, and ozonation followed by chlor(am)ination. Controlled formation potential tests were meticulously conducted at a controlled pH of 7, with precisely targeted residual chlorine concentrations maintained at 1.0±0.4 mg/L as free Cl2 over a three-day period and 2.5±0.5 mg/L as total free Cl2 over five days. The results demonstrated significant increases in the formation of DBPs, particularly HANs, HAAs, and THMs. Notably, DCAN molar yields peaked at 45.6 μmol/mol during chloramination alone and later increased to 479 μmol/mol following ozonation and subsequent chloramination. Similarly, DCAA molar yields ranged from 197 μmol/mol to 750 μmol/mol post-chlorination and from 193 to 1980 μmol/mol after ozonation with subsequent chlorination. Total trihalomethanes (TTHM) displayed a substantial variation, with molar yields ranging from 124 to 6910 μmol/mol post-chlorination, and from 187 μmol/mol to 39000 μmol/mol post-chloramination. A critical observation was the significant enhancement of N-nitrosodimethylamine (NDMA) formation, where molar yields increased to a peak of 5330 μmol/mol during ozonation with subsequent chloramination in compounds containing aromatic ring structures such as BAC, BTC, CPC, and polyDADMAC, compared to a peak of 510 μmol/mol during chloramination alone. This marked increase highlights the catalytic role of ozonation in elevating NDMA formation. Pre-ozonation effectively transformed QAS precursors, reducing their potential to form HAAs and HANs during subsequent chlorination. However, it also increased the reactivity of certain compounds, such as BTC, CPC, and BAC, leading to elevated levels of TCAA, DCAA, and DCAN. These observations highlight the dual role of ozonation in water treatment, demonstrating its capacity to both mitigate and enhance DBP formation under specific conditions. These findings highlight the need for careful management of these compounds prior to their discharge via treated wastewater into the environment to mitigate potential DBP formation during drinking water treatment. The study identifies significant gaps in our understanding of the specific pathways through which QAS transform to form intermediate products that act as DBP precursors, emphasizing the necessity for continuous monitoring and adaptive management in water treatment practices to minimize risks associated with DBP formation from QAS precursors
Understanding the Role of Discrimination in the Experience of Traumatic Stress in Latine
No full textIntroduction. Research has found that low provider culture knowledge leads to poor mental health outcomes for Latine clients (Duke et al., 2011). Further, the 2017 APA Multicultural Guidelines emphasize the need for clinicians and researchers to conceptualize clinical and empirical data from a culturally competent lens, especially considering clinician and researcher bias while understanding a psychological phenomenon. Despite this, limited research exists categorizing the unique factors that affect mental health symptoms among Latine living in the United States (U.S.) especially as it pertains to trauma stress and discrimination (Marmot, 2005; Nadal, 2018). As such, the current study used meditational statistical analysis to improve understanding of the unique relationship between microaggression experience, trauma symptoms, and psychological stress in Latine.Method. Data were collected during the spring of 2024 (January to February) through an online platform Qualtrics® where participants were monetarily compensated for their time. The research team recruited 434 participants who self-identified as Latine US residents. Result. The findings demonstrate a significant total effect linking microaggressions to psychological distress. These results suggest the presence of a meditational relationship. The significant mediation effect of trauma suggests that past experiences of trauma may exacerbate the negative impact of microaggressions on psychological well-being in Latine. Conclusion. This study sheds light on the significant impact of racial microaggressions on the mental health of Latine, highlighting the interconnectedness of experiences of microaggressions, trauma stress, and psychosocial distress. The findings underscore the need for culturally sensitive interventions aimed at addressing the unique challenges faced by Latine individuals
Characterizing GSK3β Interaction and Kinetics via Isothermal Titration Calorimetry
No full textGlycogen synthase kinase 3β (GSK3β) is a multifunctional serine/threonine kinase involved in several key signaling pathways, including glycogen metabolism, WNT/β-catenin, and Hedgehog signaling. Hyperactivity of GSK3β has been linked to Alzheimer’s disease, bipolar disorder, type II diabetes, and some cancers. Therefore, GSK3β is of interest as a target for therapeutics. Lithium ion (Li+) is a classical inhibitor of GSK3β. Structurally similar beryllium ion (Be2+) is ~1000-fold more potent. Lithium and beryllium have demonstrated pathway-specific and cell type-specific inhibition of GSK3β, prompting an investigation into the inhibitory mechanisms and thermodynamic characteristics of the metal-enzyme interaction.Isothermal titration calorimetry (ITC) is a label-free technique that measures the heat absorbed or released during binding interactions. Be2+ is hypothesized to inhibit GSK3β by competing with magnesium ions (Mg2+) for binding sites rich in acidic residues like aspartic acid. ITC binding studies utilizing model chelators and peptides featuring carboxylate groups revealed that Be2+ has a higher binding affinity than Mg2+ for carboxylate-rich binding sites. ITC can be extended to studying enzyme kinetics by measuring the heat released or absorbed during enzymatic reactions. This allows for real-time observation of reaction kinetics. This study reports the first use of an ITC enzyme assay for the kinetic analysis of a protein kinase. The ITC enzyme assay facilitates continuous monitoring of the enzyme reaction and provides mechanistic insights into the enzymatic process that may remain uncovered in conventional kinase assays. An ITC assay was developed using the single-injection method for the kinetic characterization of human GSK3β kinase activity. The assay was utilized to study the phosphorylation of a primed GSK3β substrate, the GSM phosphopeptide. The GSM phosphopeptide contains three tandem phosphorylation sites. Mutated forms of GSM, where specific phosphorylation sites were altered to alanine, were created to produce mono-site and zero-site GSM substrates. Phosphorylation of the mono-site GSM by GSK3β was an exothermic reaction and followed Michaelis-Menten kinetics, with a KM of 59 μM and kcat of 6.3 s-1. The intrinsic enthalpy of the reaction was -16 kJ/mol. The kinetic analysis for triple-site GSM phosphorylation did not conform to classical Michaelis-Menten kinetics and instead displayed a biphasic behavior. GSK3β sequentially phosphorylates substrates with multiple phosphorylation sites in tandem. A comparative analysis of reaction enthalpies and the shapes of the raw ITC thermograms for mono-site and triple-site GSM demonstrated that tandem multi-site phosphorylation by GSK3β follows a processive mechanism. The processive phosphorylation by GSK3β displays two modes: fast kinetics for ES complex formation and phosphorylation of the first site and slow kinetics for the phosphorylation of secondary and subsequent sites. This observation shows that once GSK3β initiates phosphorylation, it remains associated with the substrate to ensure complete modification of all tandem phosphorylation sites, following a mechanism designed to ensure reliability rather than speed. This provides insight into how the need for complete sequential phosphorylation by GSK3β plays a role in tightly controlled signaling pathways
Implicit Bias: Principal Leadership and Social Justice
No full textBenson & Ellison (2017) contend that among the first steps toward addressing a more diverse school and student body is an augmentation of cultural competency leadership, which begins with principals knowing how to address their own implicit biases as leaders in their schools. The purpose of this qualitative research study was to explore different ways principals address implicit biases within their schools and what is needed to help them address implicit bias with teachers and staff. The study addressed two research questions: “What do school principals perceive as biases among teachers and staff?” and “What do principals perceive is needed to help them address implicit biases in their schools?
The Effects of First Responder Stress & Trauma on Spouses and Romantic Partners
No full textFirst responder jobs pose unique difficulties due to the sheer number of traumatic events that they witness and personally experience. Research has demonstrated some effects of stress and trauma on family relationships, but the literature lacks an understanding of the ways that first responder trauma and stress affects their marriages and romantic relationships. The current study’s purpose was to investigate the experiences of first responder spouses and partners within the Las Vegas area in regards to stress, trauma, and relationship dynamics as influenced by the first responder role. In this study, 11 participants who were in a marriage or romantic relationship with a first responder were interviewed within a 60-minute time frame through the use of a virtual platform. Findings from the interviews showed that the impact of first responder job stress, the effects of repeated exposure to trauma, and first responder cultural attitudes were important aspects of the first responder relationships. These findings were developed from the following ten emergent themes: acceptance of career demands, manifestations of stress, communication patterns, work-life balance, hypervigilance, effects of trauma, mental health, support systems, personal identity, and first responder culture
Preparing Anti-Racist Teachers: A Case Study of Preservice Teachers’ Perceptions of Racism and Program Coherence in Equity-Centered Teacher Preparation
No full textThis case study explored the perceptions preservice teachers had regarding racism in educational contexts, how those perceptions were shaped by their teacher education program, and to what extent their teacher education program had coherence in preparing anti-racist teachers. Within the context of a large, minority serving institution in the Southwest preparing teachers for one of the most racially, linguistically, and socioeconomically diverse districts in the country, the need to prepare anti-racist teachers who are able to recognize and remedy opportunity gaps for multi-marginalized students is evident. Because little research has focused on the perceptions and lived experiences preservice teachers have regarding coherence of their programs in preparing future teachers for equity-centered and opportunity-oriented teaching, teacher preparation programs cannot be sure that what is espoused in the mission and vision statements is being implemented throughout the programs and what is learned by their students. Using frameworks of Critical Race Theory and Opportunity Centered Teaching, this case study sought to understand how preservice teachers perceived the coherence of their program related to equity and how teacher educators modeled and prepared their preservice teachers to enact Opportunity Centered Teaching for the benefit of the diverse students in their future classrooms. Data collection methods included document analysis, semi-structured interviews, and observations of preservice teachers in coursework with teacher educators. Preservice teachers (n = 6) and teacher educators (n = 5) were interviewed. The findings indicate participants who engaged in different contexts (less diverse and more diverse school settings) had a burgeoning awareness of racism even though all spoke in race evasive ways. The findings also indicate that a lack of coherence centered on equity produced preservice teachers who had minimal understandings of how white supremacy culture functions in education and how or why they should enact anti-racist pedagogies. Consequently, elementary preservice teachers were unable to articulate strategies beyond relationship cultivation to increase opportunities for diverse students in their future classrooms
Temporal Variations In and Predictive Values of ABG Results Prior to In-Hospital Cardiac Arrest
No full textIn-hospital cardiac arrest (IHCA) has been understudied relative to out-of-hospital cardiac arrest. Further, studies of IHCA have mainly focused on a limited number of pre-arrest patient characteristics (e.g., demographics, number and types of comorbidities). Arterial blood gas (ABG) analysis, one of the most common diagnostic tests for assessing and managing critically or acutely ill hospitalized patients, reflects pathophysiological changes associated with adverse events or complications, including IHCA. Yet the predictive and prognostic values of patterns of pre-arrest ABG parameters for IHCA have not been fully studied. The purpose of this retrospective pilot cohort study was to investigate temporal variations in and predictive values of pre-IHCA ABG values among patients with a history of cardiopulmonary diseases. Eligible patients had a history of structural heart disease, heart failure, or pulmonary diseases. Patients were excluded if their IHCA was due to trauma, drug overdose, hypothermia, drowning, chronic terminal illness such as cancer or human immunodeficiency virus, or bleeding not caused by hemorrhage in the brain or heart. Also collected were dates, times, and causes of mechanical intubation prior to IHCA and causes of mortality. Co-primary outcomes were initial rhythms of IHCA and return of spontaneous circulation (ROSC). We conducted a pilot study and the ABG results (pH, partial pressure of carbon dioxide [PaCO2], partial pressure of oxygen [PaO2], bicarbonate [HCO3-] , and lactate) from each of the 3 days prior to IHCA were extracted from the electronic health records (EHRs) of patients (N = 44) who had experienced IHCA at a single medical center. To characterize differences in ABG parameters among study days, coefficients of variation (CVs) were compared using the modified likelihood ratio test (MLRT) using the worst ABG values. Linear regression models were run for the continuous ABG parameters and logistic regression models for the dichotomous ABG variables. Overall model effect and least squares means, SDs, mean differences within and between days (with 95 % confidence intervals), p-values and effect sizes were reported for continuous variables. For categorical variables, estimates and standard errors, 95 % confidence intervals, Wald X2 variables and p-values were presented. The CVs for pH, PaCO2 , and HCO3- differed significant between study days (p \u3c .05). The least squares means with 95 % confidence intervals for pH and lactate differed significantly in days (p \u3c .01). Moderate to large effect sizes were obtained for all ABG parameters. Arterial lactate predicted initial rhythm (shockable versus non-shockable) and ROSC, while pH and HCO3- predicted ROSC. Results demonstrate, for the first time, the presence of significant variability in ABG parameters across 72 h prior to IHCA and the predictive potential of these parameters for initial rhythms of IHCA and ROSC. While validation in a larger sample is necessary, this study confirms the feasibility and potential value of exploring temporal patterns of pre-arrest ABG values from the EHRs. Findings of future larger studies on pre-arrest patterns of ABG parameters and other laboratory values may be used to design models that better predict risk for IHCA and guide patient care in the pre- and intra-arrest periods
Association Between Depressive Symptoms and Dynamic Balance Among Young Adults in the Community
No full textBackground: Detecting and addressing depression symptoms at their outset can reduce the burden on individuals and society; however, it has a limitation in that such evaluations mainly rely on self-reports. Several studies have demonstrated a strong association between motor symptoms and early depression. We aimed to associate body balance measured by the Lower Quarter Y Balance Test (YBT-LQ) with depressive symptoms among young adults in the community, to confirm the current evidence that depression negatively influences body balance. Research question: Is the YBT-LQ an objective tool for measuring and evaluating young adults’ depression risks, as well as assessing whether depression negatively influences body balance? Methods: Our participants comprised 36 young adults. We assessed their depressive symptoms using the Center for Epidemiological Studies Depression Scale (CES-D) via a Google survey, measured their body balance with the YBT-LQ, and analyzed data with Spearman’s rank-order correlation coefficient test, using SPSS version 27.0. Results: We found that the right leg’s anterior, posteromedial, and posterolateral scores— Z = − 2.129, p = .033; Z = − 2.181, p = .029; and Z = − 2.250, p = .024, respectively—and composite scores—Z = 73.00, p = .027 —were significantly lower in the group with risk for clinical depression compared to the normal group. The CES-D total score had a negative association with all YBT-LQ scores, except for the anterior score of the left leg. Among the CES-D sub-factors, somatic and retarded activity showed negative correlations with all the YBT-LQ scores. Significance: Our findings revealed that depressive symptoms have a negative association with balance, and that the YBT-LQ can be a reliable tool for measuring motor symptoms of depression, specifically among young adults