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Title: Stressors Experienced by Emergency Department Registered Nurses at the Bedside: A Phenomenological Study.
Creator: Heglund, Stephen, Wink, Diane, Andrews, Diane, Leuner, Jean, Malvey, Donna, Chase, Susan, University of Central Florida
Abstract / Description: The Emergency Department (ED) as a workplace for the Registered Nurse (RN) is a stressful environment. Reasons are thought to include interactions with other members of the interdisciplinary team as well as the situations associated with the environment of the ED such as trauma, death, sadness, joy and the general unpredictability of each moment. Studies have documented general health care workplace stress and its influence on staff, but a very limited number of studies have concentrated on...
Show moreThe Emergency Department (ED) as a workplace for the Registered Nurse (RN) is a stressful environment. Reasons are thought to include interactions with other members of the interdisciplinary team as well as the situations associated with the environment of the ED such as trauma, death, sadness, joy and the general unpredictability of each moment. Studies have documented general health care workplace stress and its influence on staff, but a very limited number of studies have concentrated on the ED. No widely published studies have identified stressors from the perspective of the ED RN.This dissertation is an interpretive phenomenological study that seeks to understand the experience of being an ED RN through the exploration of the perceptions of stress as lived by individuals who practice their art and science in this unique setting. Materials for evaluation and thematic identification were obtained through personal interviews of practicing nurses. The stories told by the participants communicated what each individual found to be negatively stressful as well as what each found to be positively stressful.Conclusions based on the findings of this work suggest a need for the ED RN to be able to depend on the presence of several factors in order to be able to function with as little distress as possible. The optimal ED environment for the RN is posited to be supportive of the individual goals of the RN, provide adequate resources and foster a communicative interdisciplinary environment. Recommendations are made to improve resource management and interdisciplinary relations.
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Date Issued: 2012
Identifier: CFE0004384, ucf:49408
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004384

Title: CORRELATION BETWEEN PREPARATION PARAMETERS AND PROPERTIES OF MOLYBDENUM BACK CONTACT LAYER FOR CIGS THIN FILM SOLAR CELLS.
Creator: Takahashi, Eigo, Dhere, Neelkanth, University of Central Florida
Abstract / Description: Molybdenum (Mo) thin film back contact layers for thin film CuIn(1-x)GaxSe2 (CIGS) solar cells were deposited onto soda lime glass substrates using a direct current (DC) planar magnetron sputtering deposition technique. Requirements for the Mo thin film as a back contact layer for CIGS solar cells are various. Sheet resistance, contact resistance to the CIGS absorber, optical reflectance, surface morphology, and adhesion to the glass substrate are the most important properties that the Mo...
Show moreMolybdenum (Mo) thin film back contact layers for thin film CuIn(1-x)GaxSe2 (CIGS) solar cells were deposited onto soda lime glass substrates using a direct current (DC) planar magnetron sputtering deposition technique. Requirements for the Mo thin film as a back contact layer for CIGS solar cells are various. Sheet resistance, contact resistance to the CIGS absorber, optical reflectance, surface morphology, and adhesion to the glass substrate are the most important properties that the Mo thin film back contact layer must satisfy. Experiments were carried out under various combinations of sputtering power and working gas pressure, for it is well known that mechanical, morphological, optical, and electrical property of a sputter-deposited Mo thin film are dependent on these process parameters. Various properties of each Mo film were measured and discussed. Sheet resistances were measured using a four-point probe equipment and minimum value of 0.25 Ω/sq was obtained for the 0.6 Ã‚Âµm-thick Mo film. Average surface roughnesses of each Mo film ranged from 15 to 26 ÃƒÂ… were measured by Dektak profilometer which was also employed to measure film thicknesses. Resistivities were calculated from the sheet resistance and film thickness of each film. Minimum resistivity of 11.9 Ã‚ÂµΩ∙cm was obtained with the Mo thin film deposited at 0.1 mTorr and 250 W. A residual stress analysis was conducted with a bending beam technique with very thin glass strips, and maximum tensile stress of 358 MPa was obtained; however, films did not exhibit a compressive stress. Adhesive strengths were examined for all films with a Ã‚Â"Scotch-tapeÃ‚Â" test, and all films showed a good adhesion to the glass substrate. Sputter-deposited Mo thin films are commonly employed as a back contact layer for CIGS and CuInSe2 (CIS)-based solar cells; however, there are several difficulties in fabricating a qualified back contact layer. Generally, Mo thin films deposited at higher sputtering power and lower working gas pressure tend to exhibit lower resistivity; however, such films have a poor adhesion to the glass substrate. On the other hand, films deposited at lower power and higher gas pressure tend to have a higher resistivity, whereas the films exhibit an excellent adhesion to the glass substrate. Therefore, it has been a practice to employ multi-layered Mo thin film back contact layers to achieve the properties of good adhesion to the glass substrate and low resistivity simultaneously. However, multi layer processes have a lower throughput and higher fabricating cost, and requires more elaborated equipment compared to single layer processes, which are not desirable from the industrial point of view. As can be seen, above mentioned process parameters and the corresponding Mo thin film properties are at the two extreme ends of the spectrum. Hence experiments were conducted to find out the mechanisms which influence the properties of Mo thin films by changing the two process parameters of working gas pressure and sputtering power individually. The relationships between process parameters and above mentioned properties were studied and explained. It was found that by selecting the process parameters properly, less resistive, appropriate-surfaced, and highly adhesive single layer Mo thin films for CIGS solar cells can be achieved.
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Date Issued: 2010
Identifier: CFE0003031, ucf:48353
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003031

Title: The Effect of Traumatic Brain Injury on Exposure Therapy in Veterans with Combat-related Posttraumatic Stress Disorder.
Creator: Ragsdale, Kathleen, Beidel, Deborah, Neer, Sandra, Bowers, Clint, Ni, Liqiang, University of Central Florida
Abstract / Description: Veterans of Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn are presenting for treatment with high rates of combat-related posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI), spurring a need for clinical research on optimal treatment strategies. While exposure therapy has long been supported as an efficacious treatment for combat-related PTSD, some clinicians are hesitant to utilize this treatment for veterans with TBI history due to presumed...
Show moreVeterans of Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn are presenting for treatment with high rates of combat-related posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI), spurring a need for clinical research on optimal treatment strategies. While exposure therapy has long been supported as an efficacious treatment for combat-related PTSD, some clinicians are hesitant to utilize this treatment for veterans with TBI history due to presumed cognitive deficits that may preclude successful engagement. The purpose of this study was to compare exposure therapy process variables in veterans with PTSD only and veterans with PTSD+TBI. Results suggest that individuals with PTSD+TBI engage successfully in exposure therapy, and do so no differently than individuals with PTSD only. Additional analyses indicated that regardless of TBI status, more severe PTSD was related to longer sessions, more sessions, and slower extinction rate during imaginal exposure. Finally, in a subset of participants, self-report of executive dysfunction did not impact exposure therapy process variables. Overall, findings indicate that exposure therapy should be the first-line treatment for combat-related PTSD regardless of presence of TBI history.
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Date Issued: 2015
Identifier: CFE0005868, ucf:50894
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005868

Title: The effect of jyoti meditation on student counselor emotional intelligence, stress, and daily spiritual experiences.
Creator: Gutierrez, Daniel, Young, Mark, Robinson, Edward, Conley, Abigail, Hagedorn, William, Ritz, Louis, University of Central Florida
Abstract / Description: Previous research has found meditation to be effective in reducing practitioner stress, improving emotional functioning, and increasing pro-social emotions, such as empathy and compassion. In addition, research examining the effects of meditation on student counselors has shown that it increases counselor self-efficacy, reduces distress, and increases cognitive empathy. Therefore, it behooves counselor educators to discover methods of integrating meditation into counselor training. The...
Show morePrevious research has found meditation to be effective in reducing practitioner stress, improving emotional functioning, and increasing pro-social emotions, such as empathy and compassion. In addition, research examining the effects of meditation on student counselors has shown that it increases counselor self-efficacy, reduces distress, and increases cognitive empathy. Therefore, it behooves counselor educators to discover methods of integrating meditation into counselor training. The meditation practice investigated in the current study is new to the counseling and psychology literature. The majority of the current research has examined transcendental and mindfulness-based practices. However, recent research has shown that spirituality has the ability to potentiate meditation. Jyoti mediation (JM), the practice used in this study, is a spiritually based practice used for spiritual and personal growth for over 500 years. This study examined whether student counselors, after participating in a JM group, would have a significantly different level of emotional intelligence, stress and daily spiritual experiences than a comparison group who received a psycho-educational curriculum. Moreover, I investigated if the frequency of meditation related to the treatment outcomes. I conducted a six week randomized controlled trial where participants (n = 60) completed self-report assessments on the first, third and sixth week of the intervention. In addition, the participants in the meditation condition were asked to complete a daily journal reporting their experiences with the meditation treatment and their frequency of practice. Participants were required to meditate once a week in the group, and requested to meditate at least ten additional minutes each day. In order to analyze the data, I conducted a repeated measures multivariate analysis of variance (RM-MANOVA). The RM-MANOVA revealed no significant difference between the two groups. However, because the range of time spent meditating was so wide, I conducted a second RM-MANOVA using only participants that meditated in group and an additional 60 minutes over the six weeks. The second RM-MANOVA approached significance in the main effects (p = .06); and revealed a significant univariate between group effect for stress. Likewise, I conducted two Pearson moment correlations to investigate the relationship between the study outcomes and meditation frequency. The first correlation revealed no significant relationship between meditation frequency and any of the independent. However, the second correlational analysis revealed a significant relationship between stress and meditation frequency. Also, both correlational analyses revealed a significant relationship between stress and emotional intelligence. In order to gain a better understanding of how the independent variables effected stress over time, I conducted a growth curve analysis (GCA). I used PROC Mixed in SAS and nested the measurement points into each individual. The GCA revealed significant non-trivial variance between individuals at initial status. In addition, the GCA revealed that emotional intelligence accounted for 27% of that variance, and when controlling for emotional intelligence there is a significant interaction between time and group. The implications and limitations of these findings are discussed.
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Date Issued: 2014
Identifier: CFE0005177, ucf:50666
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005177

Title: Role of Sleep in Exposure Therapy for Posttraumatic Stress Disorder in OIF/OEF Combat Veterans.
Creator: Mesa, Franklin, Beidel, Deborah, Neer, Sandra, Bowers, Clint, Ni, Liqiang, University of Central Florida
Abstract / Description: Exposure therapy is theorized to reduce posttraumatic stress disorder (PTSD) symptomatology by promoting habituation/extinction of fear responses to trauma-related cues. Empirical evidence indicates that emotional memory, including habituation/extinction learning, is enhanced by sleep. However, service members with combat-related PTSD often report disturbed sleep. In this study, quality of sleep and indicators of extinction learning were examined in veterans of recent wars who had completed...
Show moreExposure therapy is theorized to reduce posttraumatic stress disorder (PTSD) symptomatology by promoting habituation/extinction of fear responses to trauma-related cues. Empirical evidence indicates that emotional memory, including habituation/extinction learning, is enhanced by sleep. However, service members with combat-related PTSD often report disturbed sleep. In this study, quality of sleep and indicators of extinction learning were examined in veterans of recent wars who had completed an exposure-based PTSD intervention. Fifty-five participants were categorized into two groups based on self-reported quality of sleep: low sleep disruption severity (LSDS; N = 29) and high sleep disruption severity (HSDS; N = 26). Participants in the LSDS group exhibited faster habituation to their traumatic memories and reported less PTSD symptomatology during and following treatment relative to participants in the HSDS group. These findings indicate that individuals with combat-related PTSD reporting less disturbed sleep experience greater extinction learning during exposure therapy. Thus, incorporating interventions that target PTSD-related sleep disturbances may be one way to maximize exposure therapy outcomes in service members with PTSD.
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Date Issued: 2016
Identifier: CFE0006355, ucf:51520
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006355

Title: Cardiac Autonomic Control in Patients with Metabolic Syndrome.
Creator: Mitchell, Jonathan, Cassisi, Jeffrey, Bedwell, Jeffrey, Beidel, Deborah, University of Central Florida
Abstract / Description: Metabolic syndrome (MetS) encompasses metabolic abnormalities that substantially increase risk for chronic illnesses. MetS and stress are closely related; the pathophysiology of MetS involves dysregulated stress response in both the physiological and psychological domains. In an effort to further clarify the relationship between metabolic abnormalities and autonomic dysregulation, we used ambulatory impedance cardiography to examine indicators of cardiac autonomic control (CAC) in a sample of...
Show moreMetabolic syndrome (MetS) encompasses metabolic abnormalities that substantially increase risk for chronic illnesses. MetS and stress are closely related; the pathophysiology of MetS involves dysregulated stress response in both the physiological and psychological domains. In an effort to further clarify the relationship between metabolic abnormalities and autonomic dysregulation, we used ambulatory impedance cardiography to examine indicators of cardiac autonomic control (CAC) in a sample of 50 adult primary care patients with and without MetS. Indices of sympathetic and parasympathetic influences on cardiovascular functioning were assessed in the context of psychological stressors and compared across experimental groups and examined in relation to self-reported health measures. Primary results suggest that while our experimental groups did not differ significantly on baseline measures, patterns of responses to experimentally induced stressors were largely consistent with our predictions, and demonstrate that individuals with MetS responded to stress cues with more maladaptive CAC scores. Moreover, in line with previous work, we found that elements of CAC in our sample were predictive of both cardiovascular disease and self-reported environmental quality of life. Overall, our results suggest that maladaptive physiological manifestations of the stress response are evident among individuals with MetS and may also be related to long-term health outcomes. The present study carries implications for both evaluation and assessment as well as treatment delivery and monitoring. In addition, the ambulatory nature of data collection demonstrated here supports trends toward mHealth and related initiatives in emerging modes of healthcare delivery.
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Date Issued: 2016
Identifier: CFE0006359, ucf:51519
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006359

Title: The Impact of Automation and Stress on Human Performance in UAV Operation.
Creator: Lin, Jinchao, Matthews, Gerald, Reinerman, Lauren, Szalma, James, Funke, Gregory, University of Central Florida
Abstract / Description: The United States Air Force (USAF) has increasing needs for unmanned aerial vehicle (UAV) operators. Automation may enable a single operator to manage multiple UAVs at the same time. Multi-UAV operation may require a unique set of skills and the need for new operators calls for targeting new populations for recruitment. The objective of this research is to develop a simulation environment for studying the role of individual differences in UAV operation under different task configurations and...
Show moreThe United States Air Force (USAF) has increasing needs for unmanned aerial vehicle (UAV) operators. Automation may enable a single operator to manage multiple UAVs at the same time. Multi-UAV operation may require a unique set of skills and the need for new operators calls for targeting new populations for recruitment. The objective of this research is to develop a simulation environment for studying the role of individual differences in UAV operation under different task configurations and investigate predictors of performance and stress. Primarily, the study examined the impact of levels of automation (LOAs), as well as task demands, on task performance, stress and operator reliance on automation. Two intermediate LOAs were employed for two surveillance tasks included in the simulation of UAV operation. Task demand was manipulated via the high and low frequency of events associated with additional tasks included in the simulation. The task demand and LOA manipulations influenced task performance generally as expected. The task demand manipulations elicited higher subjective distress and workload. LOAs did not affect operator workload but affected reliance behavior. Also, this study examined the role of individual differences in simulated UAV operation. A variety of individual difference factors were associated with task performance and with subjective stress response. Video gaming experience was linked to lower distress and better performance, suggesting possible transfer of skills. Some gender differences were revealed in stress response, task performance, but all the gender effects became insignificant with gaming experience controlled. Generally, the effects of personality were consistent with previous studies, except some novel findings with the performance metrics. Additionally, task demand was found to moderate the influence of personality factors on stress response and performance metrics. Specifically, conscientiousness was associated with higher subjective engagement and performance when demands were higher. This study supports future research which aims to improve the dynamic interfaces in UAV operation, optimize operator reliance on automation, and identify individuals with the highest aptitude for multi-UAV control.
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Date Issued: 2017
Identifier: CFE0006951, ucf:51630
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006951

Title: Temperament and Child Maltreatment: A Closer Look at the Interactions Among Mother and Child Temperament, Stress and Coping, Emotional and Behavioral Regulation, and Child Maltreatment Potential.
Creator: Lowell, Amanda, Renk, Kimberly, Paulson, Daniel, Sims, Valerie, University of Central Florida
Abstract / Description: Several theoretical risk models were proposed previously regarding the prediction of child maltreatment. Although child maltreatment was predicted individually in these models by such variables as parent temperament, emotional and behavioral regulation, stress, coping, and child temperament, these variables were not yet examined collectively. As such, a new transactional theory was proposed for the current study. As part of this study, a national community sample of 158 culturally diverse...
Show moreSeveral theoretical risk models were proposed previously regarding the prediction of child maltreatment. Although child maltreatment was predicted individually in these models by such variables as parent temperament, emotional and behavioral regulation, stress, coping, and child temperament, these variables were not yet examined collectively. As such, a new transactional theory was proposed for the current study. As part of this study, a national community sample of 158 culturally diverse mothers of young children who were between the ages of 1(&)#189;- to 5-years rated their own temperament, emotional and behavioral regulation abilities, parenting stress, daily hassles, and coping behaviors as well as their young children's temperament. Correlational analyses demonstrated many significant relationships among the variables of interest. In addition, hierarchical regression analyses suggested that several parent (i.e., mother mood quality, mother flexibility/rigidity, emotion dysregulation, parenting stress, cumulated severity of stress, and emotion-focused coping) and child characteristics (i.e., young child mood quality) added unique incremental variance to the prediction of child maltreatment potential. Finally, mediation analyses indicated that mothers' emotion dysregulation mediated the relationship between mothers' flexibility/rigidity and child maltreatment potential. Overall, this study contributed information regarding the importance of emotion dysregulation as a mechanism through which difficult mother temperament may be related to increased child maltreatment potential. Accordingly, these findings suggested that emotion regulation skills may serve as a potential point of intervention for mothers who are at increased risk for child maltreatment due to difficult temperament characteristics.
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Date Issued: 2015
Identifier: CFE0005652, ucf:50172
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005652

Title: Interpreting Diet and Nutritional Stress in Napoleon's Grand Army using Stable Carbon and Nitrogen Isotope Analysis.
Creator: Holder, Sammantha, Dupras, Tosha, Schultz, John, Williams, Lana, Toyne, Jennifer, University of Central Florida
Abstract / Description: A mass grave containing the remains of at least 3269 Napoleonic soldiers from 1812 was discovered in Vilnius, Lithuania in 2001. Stable carbon and nitrogen isotopic analyses were performed on collagen from 78 femoral samples to explore dietary variation within the sample. Starvation and nutritional distress were also evaluated through the examination of nitrogen enrichment in bone collagen. Clinical studies have demonstrated that enriched nitrogen isotope values can indicate periods of...
Show moreA mass grave containing the remains of at least 3269 Napoleonic soldiers from 1812 was discovered in Vilnius, Lithuania in 2001. Stable carbon and nitrogen isotopic analyses were performed on collagen from 78 femoral samples to explore dietary variation within the sample. Starvation and nutritional distress were also evaluated through the examination of nitrogen enrichment in bone collagen. Clinical studies have demonstrated that enriched nitrogen isotope values can indicate periods of nutritional stress and starvation; however, this is the first study to examine its use as a diagnostic indicator of starvation in a historical population using bone tissue. According to the carbon isotope data, a vast majority of the soldiers in this sample consumed predominantly C3 plants with only five individuals consuming more than 50% of their plant dietary protein in the form of C4 plants, with ?13C ratios for this sample ranging from -19.22‰ to -11.76‰ and a mean of -17.18‰. This conforms to expectations given that a majority of human plant consumption in Europe is C3 pathway plants. Twenty-nine individuals exhibit enriched ?15N values, with ?15N values for this sample ranging from 7.14‰ to 13.63‰ and a mean of 10.49‰. The combination of historical and isotopic evidence suggests prolonged nutritional stress may be the cause of enrichment in this sample. The results of this study demonstrate the applicability of this method on archaeological samples as a line of evidence in the investigation of starvation and famine.
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Date Issued: 2013
Identifier: CFE0005004, ucf:49982
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005004

Title: Probing the Influence of Cx43 and Glucose on Endothelial Biomechanics.
Creator: Islam, Md Mydul, Steward, Robert, Kassab, Alain, Mansy, Hansen, Willenberg, Bradley, University of Central Florida
Abstract / Description: Endothelial cells (ECs) form the innermost layer of all vasculature and constantly receive both biochemical and biomechanical signals, yielding a plethora of biomechanical responses. In response to various biochemical or biomechanical cues, ECs have been documented to generate biomechanical responses such as tractions and intercellular stresses between the cell and substrate and between adjacent cells in a confluent monolayer, respectively. Thus far, the ability of endothelial tight junctions...
Show moreEndothelial cells (ECs) form the innermost layer of all vasculature and constantly receive both biochemical and biomechanical signals, yielding a plethora of biomechanical responses. In response to various biochemical or biomechanical cues, ECs have been documented to generate biomechanical responses such as tractions and intercellular stresses between the cell and substrate and between adjacent cells in a confluent monolayer, respectively. Thus far, the ability of endothelial tight junctions and adherens junctions to transmit intercellular stresses has been actively investigated, but the role of gap junctions is currently unknown. In addition, there is no report of the independent influence of hyperglycemia on endothelial biomechanics present in the literature. To fill these gaps, we conducted a two-fold study where we investigated the influence of endothelial gap junction Cx43 and hyperglycemia in endothelial tractions and intercellular stress generation. In the first study, we selectively disrupted and enhanced EC gap junction Cx43 by using 2',5'-dihydroxychalcone and retinoic acid, respectively and in the second study, we cultured ECs in both normal glucose and hyperglycemic condition for 10 days. In both studies, tractions and intercellular stresses were calculated using traction force microscopy (TFM) and monolayer stress microscopy (MSM), respectively. Our results reveal that Cx43 downregulation increased as well as decreased endothelial avg. normal intercellular stresses in response to a low (0.83 (&)#181;M) and a high dose (8.3 (&)#181;M) chalcone treatment, respectively, while Cx43 upregulation decreases avg. normal intercellular stresses in both treatment conditions (2.5 (&)#181;M and 25 (&)#181;M) compared to control. In addition, we observed a decrease in intercellular stresses with hyperglycemic condition compared to control. The results we present here represent, for the first time, detailed and comprehensive biomechanical analysis of endothelial cells under the influence of glucose and the gap junction Cx43. We believe our results will provide valuable insights into endothelial permeability, barrier strength as well as leading to a greater understanding of overall endothelial mechanics.
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Date Issued: 2019
Identifier: CFE0007819, ucf:52805
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007819

Title: CONSIDERING STRESS IN A NURSING STUDENT CONTEXT: PRE-ADMISSION TO PRE-GRADUATION.
Creator: Regner, Daniel M, Andrews, Diane, University of Central Florida
Abstract / Description: In moderation, stress is a normal response to a perceived challenge which can motivate an individual to perform at their best. Nursing students consistently report a significant amount of stress which has been found to be greater than their non-nursing peers. The purpose of this study is to assess the level of stress reported by second-semester freshman and sophomore students who have declared nursing as a major, compared with the level of stress experienced by junior and senior students who...
Show moreIn moderation, stress is a normal response to a perceived challenge which can motivate an individual to perform at their best. Nursing students consistently report a significant amount of stress which has been found to be greater than their non-nursing peers. The purpose of this study is to assess the level of stress reported by second-semester freshman and sophomore students who have declared nursing as a major, compared with the level of stress experienced by junior and senior students who are enrolled in the university's nursing program. Through this comparison, a conclusion can be drawn as to the level of stress experienced while enrolled in a nursing program, with the level of stress prior to being exposed to the challenges presented by the program. It is intended that the outcomes from this study can be utilized to address stress as it relates to a nursing student from pre-admission through graduation.
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Date Issued: 2018
Identifier: CFH2000300, ucf:45876
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000300

Title: THE MEDIATING ROLES OF COPING AND SOCIAL SUPPORT ON ADOLESCENT LESBIAN HOMELESSNESS.
Creator: Craft, Katelynn, Jacinto, George, University of Central Florida
Abstract / Description: This paper analyzes the stress and coping mechanisms of lesbian homeless adolescents to identify potential buffers against homelessness. The Minority Stress Model and identity theories are used as a framework to interpret the findings in the literature. Based on the findings in the literature, it is possible to conclude that lesbian homeless youth are more susceptible to minority stress due to a lack of adaptive coping resources and social support. Increased levels of minority stress may lead...
Show moreThis paper analyzes the stress and coping mechanisms of lesbian homeless adolescents to identify potential buffers against homelessness. The Minority Stress Model and identity theories are used as a framework to interpret the findings in the literature. Based on the findings in the literature, it is possible to conclude that lesbian homeless youth are more susceptible to minority stress due to a lack of adaptive coping resources and social support. Increased levels of minority stress may lead to internalizing and externalizing symptoms that cause runaway and throwaway episodes in homeless youth. This paper proposes a new model to understand the internal and environmental factors that contribute to homelessness in lesbian adolescents.
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Date Issued: 2015
Identifier: CFH0004748, ucf:45368
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004748

Title: EFFECTS OF BOND COAT SURFACE PREPARATION ON THERMAL CYCLING LIFETIME AND FAILURE CHARACTERISTICS OF THERMAL BARRIER COATINGS.
Creator: Liu, Jing, Sohn, Yong-ho, University of Central Florida
Abstract / Description: Thermal barrier coatings (TBCs) have been widely used in gas turbine engines to protect the underlying metal from high operating temperature so as to improve the durability of the components and enhance the engine efficiency. However, since the TBCs always operate in a demanding high-temperature environment of aircraft and industrial gas-turbine engines, a better understanding of this complex system is required to improve the durability and reliability.The objective of this study is to...
Show moreThermal barrier coatings (TBCs) have been widely used in gas turbine engines to protect the underlying metal from high operating temperature so as to improve the durability of the components and enhance the engine efficiency. However, since the TBCs always operate in a demanding high-temperature environment of aircraft and industrial gas-turbine engines, a better understanding of this complex system is required to improve the durability and reliability.The objective of this study is to investigate the effects of surface modification for the NiCoCrAlY bond coats on the thermal cycling lifetime and failure characteristics of TBCs. Parameters of modification for the bond coats included as-sprayed, barrel-finished, hand-polished and pre-oxidation heat treatment at 1100 C in =10-8 atm up to 4 hours, carried out prior to the electron beam physical vapor deposition (EB-PVD) of ZrO2-7wt% Y2O3 (7YSZ) ceramic topcoat. The resulting characteristics of the bond coat and the thermally grown oxide (TGO) scale were initially documented by surface roughness, phase constituents of the TGO scale, and residual stress of the TGO scale. The thermal cycling test consisted of 10-minute heat-up to 1121 C, 40-minute hold at 1121 C, and 10-minute forced air-quench. As-coated and thermally-cycled TBCs were characterized by optical profilometry (OPM), photo-stimulated luminescence spectroscopy (PSLS), optical microscopy, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), and scanning/transmission electron microscopy (TEM/STEM) equipped with high angle annular dark field (HAADF) and X-ray energy dispersive spectroscopy (XEDS). TBC specimens for TEM/STEM analysis were prepared by focused ion beam (FIB) in-situ lift-out (INLO) technique.Superior thermal cycling lifetime was observed for TBCs with as-sprayed bond coats regardless of pre-oxidation heat treatment, and TBCs with hand-polished bond coats only after pre-oxidation heat treatment. With pre-oxidation heat treatment, relative photostimulated luminescence intensity of the equilibrium ¦Á-Al2O3 increased. Thus, the improvement in TBC lifetime can be correlated with an increase in the amount of ¦Á-Al2O3 in the TGO scale, given a specific surface modification/roughness. The lifetime improvement due to pre-oxidation was particularly significant to TBCs with smooth hand-polished bond coats and negligible for TBCs with rough as-sprayed bond coats.Spallation-fracture paths depended on the lifetime of TBCs. Premature spallation of TBCs occurred at the interface between the YSZ and TGO. Longer durability can be achieved by restricting the fracture paths to the TGO/bond coat interface. Small particulate phase observed through the TGO scale was identified as Y2O3 (cubic) by diffraction analysis on TEM. While small addition of Y in the NiCoCrAlY bond coat helps the adhesion of the TGO scale, excessive alloying can lead to deleterious effects.
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Date Issued: 2004
Identifier: CFE0000097, ucf:46083
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000097

Title: MECHANISMS OF LIFETIME IMPROVEMENT IN THERMAL BARRIER COATINGS WITH HF AND/OR Y MODIFICATION OF CMSX-4 SUPERALLOY SUBSTRATES.
Creator: Liu, Jing, Sohn, Yong ho, University of Central Florida
Abstract / Description: In modern turbine engines for propulsion and energy generation, thermal barrier coating (TBCs) protect hot-section blades and vanes, and play a critical role in enhancing reliability, durability and operation efficiency. In this study, thermal cyclic lifetime and microstructural degradation of electron beam physical vapor deposited (EB-PVD) Yttria Stabilized Zirconia (YSZ) with (Ni,Pt)Al bond coat and Hf- and/or Y- modified CMSX-4 superalloy substrates were examined. Thermal cyclic lifetime...
Show moreIn modern turbine engines for propulsion and energy generation, thermal barrier coating (TBCs) protect hot-section blades and vanes, and play a critical role in enhancing reliability, durability and operation efficiency. In this study, thermal cyclic lifetime and microstructural degradation of electron beam physical vapor deposited (EB-PVD) Yttria Stabilized Zirconia (YSZ) with (Ni,Pt)Al bond coat and Hf- and/or Y- modified CMSX-4 superalloy substrates were examined. Thermal cyclic lifetime of TBCs was measured using a furnace thermal cycle test that consisted of 10-minute heat-up, 50-minute dwell at 1135C, and 10-minute forced-air-quench. TBC lifetime was observed to improve from 600 cycles to over 3200 cycles with appropriated Hf- and/or Y alloying of CMSX-4 superalloys. This significant improvement in TBC lifetime is the highest reported lifetime in literature with similar testing parameters. Beneficial role of reactive element (RE) on the durability of TBCS were systematically investigated in this study. Photostimulated luminescence spectroscopy (PL) was employed to non-destructively measure the residual stress within the TGO scale as a function of thermal cycling. Extensive microstructural analysis with emphasis on the YSZ/TGO interface, TGO scale, TGO/bond coat interface was carried out by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and scanning electron microscopy (STEM) as a funcion of thermal cycling including after the spallation failure. Focused ion beam in-situ lift-out (FIB-INLO) technique was employed to prepare site-specific TEM specimens. X-ray diffraction (XRD) and secondary ion mass spectroscopy (SIMS) were also employed for phase identification and interfacial chemical analysis. While undulation of TGO/bond coat interface (e.g., rumpling and ratcheting) was observed to be the main mechanism of degradation for the TBCs on baseline CMSX-4, the same interface remained relatively flat (e.g., suppressed rumpling and ratcheting) for durable TBCs on Hf- and/or Y-modified CMSX-4. The fracture paths changed from the YSZ/TGO interface to the TGO/bond coat interface when rumpling was suppressed. The geometrical incompatibility between the undulated TGO and EB-PVD YSZ lead to the failure at the YSZ/TGO interface for TBCs with baseline CMSX-4. The magnitude of copressive residual stress within the TGO scale measured by PL gradually decreased as a function of thermal cycling for TBCs with baseline CMSX-4 superalloy substrates. This gradual decrease corrsponds well to the undulation of the TGO scale that may lead to relaxation of the compressive residual stress within the TGO scale. For TBCs with Hf- and/or Y-modified CMSX-4 superalloy substrates, the magnitude of compressive residual stress within the TGO scale remained relatively constant throughout the thermal cycling, although PL corresponding to the stress-relief caused by localized cracks at the TGO/bond coat interface and within the TGO scale was observed frequently starting 50% of lifetime. A slightly smaller parabolic growth constant and grain size of the TGO scale was observed for TBCs with Hf- and/or Y- modified CMSX-4. Small monoclinic HfO2 precipitates were observed to decorate grain boundaries and the triple pointes within the alpha-Al2O3 scale for TBCs with Hf- and/or Y-modified CMSX-4 substrates. Segregation of Hf/Hf4+ at the TGO/bond coat interfaces was also observed for TBCs with Hf- and/or Y-modified CMSX-4 superalloys substrates. Adherent and pore-free YSZ/TGO interface was observed for TBCs with Hf- and/or Y-modified CMSX-4, while a significant amount of decohesion at the YSZ/TGO interface was observed for TBCs with baseline CMSX-4. The beta-NiAl(B2) phase in the (Ni,Pt)Al bond coat was observed to partially transform into gama prime-Ni3Al (L12) phase due to depletion of Al in the bond coat during oxidation. More importantly, the remaining beta-NiAl phase transformed into L10 martensitic phase upon cooling even though there was no significant difference in these phase transformations for all TBCs. Results from these microstructural observations are documented to elucidate mechanisms that suppress the rumpling of the TGO/bond coat interface, which is responsible for superior performance of EB-PVD TBCs with (Ni,Pt)Al bond coat and Hf- and/or Y-modified CMXS-4 superalloy.
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Date Issued: 2007
Identifier: CFE0001872, ucf:47382
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001872

Title: LOCUS OF CONTROL AND SELF-EFFICACY: POTENTIAL MEDIATORS OF STRESS, ILLNESS, AND UTILIZATION OF HEALTH SERVICES IN COLLEGE STUDENTS.
Creator: Roddenberry, Angela, Renk, Kimberly, University of Central Florida
Abstract / Description: Stress has been linked to increased illness in several biologically based studies. In contrast, only a limited number of studies have assessed psychological variables related to stress, with self-efficacy and locus of control serving as potentially important variables. Thus, the current study investigated the mediating effects of self-efficacy and locus of control in the relationship between stress, psychological and physical symptoms, and the utilization of health services in college...
Show moreStress has been linked to increased illness in several biologically based studies. In contrast, only a limited number of studies have assessed psychological variables related to stress, with self-efficacy and locus of control serving as potentially important variables. Thus, the current study investigated the mediating effects of self-efficacy and locus of control in the relationship between stress, psychological and physical symptoms, and the utilization of health services in college students. Results suggested that stress was correlated positively with symptoms. External locus of control was correlated positively with stress and symptoms, and self-efficacy was correlated negatively with stress and symptoms. Further, structural equation modeling was used to test two separate models. The first model examined the relationships between stress and symptoms and between symptoms and utilization of health services. Although the path coefficients suggested that there were direct relationships, the data did not adequately fit this model. The second model examined the potential mediational effects of locus of control and self-efficacy on the relationship between stress and symptoms. The path coefficients for the second model were consistent with a mediation effect for locus of control in the relationship between stress and symptoms; however, when this model was tested for full mediation, the data did not fit the model. These results highlight the importance of having future studies examine and identify potential mediators of the stress and illness link. Implications for reducing health care costs and promoting better mental and physical health are discussed.
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Date Issued: 2007
Identifier: CFE0001831, ucf:47337
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001831

Title: TESTING OF WRIST-WORN-FITNESS-TRACKING DEVICES DURING COGNITIVE STRESS: A VALIDATION STUDY.
Creator: Chudy, Nicole S, McConnell, Daniel, University of Central Florida
Abstract / Description: The intent of this thesis was to test if one of the many fitness-tracking devices, Microsoft's Band 2 (MSB2), is accurate and reliable in detecting changes in Heart Rate (HR) and R-R intervals, during the repeated trial of two conditions of a working-memory test known as the N-Back. A 2 (devices: ECG, MSB2) x 4 (epochs: baseline 1, 1-back task, baseline 2, 3-back task) repeated measures factorial design was conducted. The participants were simultaneously equipped to the MSB2 and an...
Show moreThe intent of this thesis was to test if one of the many fitness-tracking devices, Microsoft's Band 2 (MSB2), is accurate and reliable in detecting changes in Heart Rate (HR) and R-R intervals, during the repeated trial of two conditions of a working-memory test known as the N-Back. A 2 (devices: ECG, MSB2) x 4 (epochs: baseline 1, 1-back task, baseline 2, 3-back task) repeated measures factorial design was conducted. The participants were simultaneously equipped to the MSB2 and an electrocardiogram (ECG). The results of this study validated the MSB2 for the use in a cognitive task. The study suggests that fitness-tracking devices with similar sampling rates and features are candidates for further exploration as alternatives to ECG, in hope of making the inclusion of physiological data in psychological research more available and accessible.
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Date Issued: 2017
Identifier: CFH2000193, ucf:45980
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000193

Title: THE ROLE OF STRESS IN THE DIFFERENTIAL DIAGNOSIS OF APRAXIA OF SPEECH AND APHASIA.
Creator: Ferranti, Jennifer G, Troche, Joshua, Bislick-Wilson, Lauren, University of Central Florida
Abstract / Description: The intent of this thesis is to explore and develop the quantification of AOS features, particularly the deficits of prosodic elements, lexical stress and duration. This study investigated whether PVI can be used as a sensitive tool for the differential diagnosis of AOS. Specifically, we sought to determine whether analysis of vowel length of stressed and unstressed syllables is helpful in differentiating between individuals with AOS and aphasia versus aphasia alone. Significant differences...
Show moreThe intent of this thesis is to explore and develop the quantification of AOS features, particularly the deficits of prosodic elements, lexical stress and duration. This study investigated whether PVI can be used as a sensitive tool for the differential diagnosis of AOS. Specifically, we sought to determine whether analysis of vowel length of stressed and unstressed syllables is helpful in differentiating between individuals with AOS and aphasia versus aphasia alone. Significant differences support the hypothesis that PVI, analyzed from vowel length, is uniquely affected in AOS. This yields reason for further research in prosodic deficits in differential diagnosis, as well as application of this theory for a speech-language pathologist.
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Date Issued: 2018
Identifier: CFH2000388, ucf:45746
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000388

Title: FACTORS CONTRIBUTING TO THE NEGATIVE AND UNHEALTHY PSYCHOLOGICAL CONDITIONS IN THE ED RN.
Creator: Nieves, Ariana M, Heglund, Stephen, Dever, Kimberly, University of Central Florida
Abstract / Description: The emergency department is a stressful environment. Emergency department registered nurses (ED RNs) are at an increased risk of development of negative and unhealthy psychological conditions due to their frequent exposure to stress and traumatic events. These conditions include post-traumatic stress disorder, compassion fatigue, and burnout syndrome, which are already known to be common in the emergency department registered nurse population. It is important to understand the factors that...
Show moreThe emergency department is a stressful environment. Emergency department registered nurses (ED RNs) are at an increased risk of development of negative and unhealthy psychological conditions due to their frequent exposure to stress and traumatic events. These conditions include post-traumatic stress disorder, compassion fatigue, and burnout syndrome, which are already known to be common in the emergency department registered nurse population. It is important to understand the factors that influence the development of these psychological conditions in order to provide better education to nurses regarding prevention of the development of these psychological conditions. This literature review aimed to identify articles that examined the factors associated with post-traumatic stress disorder, compassion fatigue, and burnout syndrome. Databases searched included but were not limited to CINAHL, MEDLINE, and PsycINFO. The determinants discussed in this paper include personality traits, social support, coping style, workplace violence, work environment, internal perceptions held by the nurse, and external perceptions held by the patient. Limited research exists regarding the factors influencing the development of compassion fatigue in the ED RN.
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Date Issued: 2019
Identifier: CFH2000462, ucf:45745
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000462

Title: EFFECTS OF CAFFEINATED ENERGY DRINK AND ALCOHOL USAGE ON PERCEIVED STRESS AND BURNOUT IN UNDERGRADUATE STUDENTS.
Creator: Patel, Arjun, Webster, Danielle, University of Central Florida
Abstract / Description: Caffeinated energy beverages (CEDs) are a growing supplement being consumed by a large number of young adults aged 18 to 24 years of age. As these CEDs contain nutritional supplements, they are not classified the same way other beverages such as sodas are and they can thus bypass regulation by the Food and Drug Administration. Without regulation by this governing body, it is important to understand how these supplements may be affecting their target population. In this study, students from a...
Show moreCaffeinated energy beverages (CEDs) are a growing supplement being consumed by a large number of young adults aged 18 to 24 years of age. As these CEDs contain nutritional supplements, they are not classified the same way other beverages such as sodas are and they can thus bypass regulation by the Food and Drug Administration. Without regulation by this governing body, it is important to understand how these supplements may be affecting their target population. In this study, students from a large university were recruited in order to determine patterns of CED usage as well as how CED usage may affect perceived stress and burnout. Alcohol usage, another type of beverage commonly consumed in this population, was also assayed in this group in order to determine how perceived stress and burnout are affected. The study was case-control in nature, as regular users of CEDs were compared against students who were not regular consumers. From the data, no major relationships could be identified in regards to perceived stress, burnout, and CED usage. However, extracurricular activity was found to be somewhat predictive of CED usage while alcohol usage was found to be negatively correlated with perceived stress.
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Date Issued: 2015
Identifier: CFH0004787, ucf:45333
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004787

Title: METHOD TO DISCRETIZE CONTINUOUS GRADIENT STRUCTURES AND CALCULATE THERMAL RESIDUAL STRESSES WITHIN LAYERED FUNCTIONALLY GRADED CERAMICS.
Creator: Neale, Ryan E, Orlovskaya, Nina, University of Central Florida
Abstract / Description: Functionally graded materials (FGMs) are an advanced class of material which seeks to leverage the strengths of one material to mitigate the weaknesses of another. This allows for operation in extreme environments or conditions where materials properties must change at various locations within a structure. Fabrication of this advanced class of material is limited due to geometric, economic, and material constraints inherent in the various methods. For this reason, a model was developed to...
Show moreFunctionally graded materials (FGMs) are an advanced class of material which seeks to leverage the strengths of one material to mitigate the weaknesses of another. This allows for operation in extreme environments or conditions where materials properties must change at various locations within a structure. Fabrication of this advanced class of material is limited due to geometric, economic, and material constraints inherent in the various methods. For this reason, a model was developed to discretize continuous gradient curves to allow for the use of a step-wise approximations to such gradients. These alternative step-wise gradients would allow for the use of numerous manufacturing techniques which have improved composition control, cost of processing, cost of equipment, and equipment availability. One such technique, tape casting, was explored due to its robustness and ability to create layered ceramics. Since ceramics are inherently brittle materials, they serve to be strengthened by the thermal residual stresses that form in the creation of these step-wise graded composites. With models to calculate these residual stresses and determine step-wise approximations of various compositional gradients, the process of designing these layered ceramics can be significantly improved.
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Date Issued: 2019
Identifier: CFH2000530, ucf:45633
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000530

stress (37)	+ -
Stress (17)	+ -
PTSD (6)	+ -
anxiety (5)	+ -
coping (5)	+ -

burnout (4)	+ -
exposure therapy (4)	+ -
health (4)	+ -
residual stress (4)	+ -
College Students (3)	+ -
Coping (3)	+ -
Nurse (3)	+ -
acculturative stress (3)	+ -
compassion fatigue (3)	+ -
posttraumatic stress disorder (3)	+ -
secondary traumatic stress (3)	+ -
synchrotron (3)	+ -
Anxiety (2)	+ -
Ceramics (2)	+ -
Compassion Fatigue (2)	+ -
Cortisol (2)	+ -
ER stress (2)	+ -
Emergency Department (2)	+ -
FEA (2)	+ -
Finite Element Analysis (2)	+ -
Hill Yield Criterion (2)	+ -
Inconel 718 (2)	+ -
Latinos (2)	+ -
Lode angle (2)	+ -
Mechanical Testing (2)	+ -

ETD Collection (101)	+ -
Honors Collection (31)	+ -

University of Central Florida (132)	+ -
Bowers, Clint (10)	+ -
Beidel, Deborah (9)	+ -
Orlovskaya, Nina (8)	+ -
Raghavan, Seetha (8)	+ -

Gou, Jihua (7)	+ -
Bai, Yuanli (6)	+ -
Gordon, Ali (6)	+ -
Hancock, Peter (6)	+ -
Renk, Kimberly (5)	+ -
Sohn, Yongho (5)	+ -
Andrews, Diane (4)	+ -
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Neer, Sandra (4)	+ -
Self, William (4)	+ -
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Vaidyanathan, Raj (3)	+ -
Young, Mark (3)	+ -
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