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Development of High-Performance Coaches and Burnout
No full textCoach education is imperative, especially as coaching moves towards professionalization (Lara-Bercial, 2022). The literature has shown that high-performance coaches are closest to fitting the criteria of a profession (Lara-Bercial et al., 2022) while also being at risk of experiencing burnout due to the high level of stress faced within their job (Bentzen et al., 2014; Olusoga & Kenttä, 2016). The purpose of this study was twofold. First to have a more comprehensive understanding of Australian Athletics high-performance coaches’ wants and needs regarding coaching education as it pertains to coach wellbeing and burnout; and second, to have an in-depth exploration of select high-performance coaches’ awareness and experiences with burnout. An explanatory mixed-methods sequential research design was employed to gather data across three phases. In phase one, high-performance coaches within the Australian Athletics database (N=172) shared their preferences for coach education as it pertains to burnout, their general knowledge about burnout, and demographic/general information about their coaching. In phase two, 75 high-performance coaches completed the MBI-ES to ascertain current scores on emotional exhaustion, depersonalization and personal accomplishment. In phase three, semi-structured interviews were conducted with 10 high-performance coaches who meet the specific inclusion criteria based on their levels of burnout on the three components. A cognitive-affective theory lens was utilized within this study, while the self-determination theory also appeared throughout the results. Awareness of topics surrounding burnout, intervention strategies and organization intervention/support were reported by coaches as something they want included within their coach education. Insights from this data were that high-performance coaches believe that burnout is a prevalent issue within coaching, and education on burnout and topics related to burnout would be beneficial. Consistent with previous burnout research themes emerged on factors that have been identified as influencing burnout levels including work life balance, work balance, lack of control, lack of recovery, pressure and personality. One additional theme emerged which was the environment. Suggestions for reducing the risk of burnout are presented including organizational support, mentorships, community of practice, a third party individual high-performance coaches could go to, recovery, self-care, and effective communication
Assessment of Asymmetries in Lower Limb Kinetics during a Dynamic Hop Task following ACL Reconstruction
No full textIntroduction: ACL Return to Sport Assessments include tests of single-legged function. These tests may overestimate rehabilitation status. The purpose of this study was to determine if a double-legged double hop will reveal quantitative biomechanical asymmetries that may be present at the time of return to sport in athletes following ACL reconstruction. Specific Aims: Specific Aims 1 and 2 compared hip and knee extension moments between limbs and groups during a double leg double hop. Specific Aim 3 compared the relative joint work contributions of the hip, knee, and ankle between limbs and groups during the double leg double hop Methods: Twenty-one individuals who have undergone a unilateral ACL reconstruction (8 females, 13 males; age = 19.04±3.47 years; height = 68.52±4.11 in; weight = 163.52±27.51 lbs) and twenty-one sex and activity level matched controls (8 females, 13 males; age = 22.85±2.97; height = 69.23±3.88 in; weight = 162.48±26.90 lbs) participated in this study. This study assessed the three-dimensional kinematics and kinetics of the hip, knee, and ankle joints during a dynamic double-legged double-hop task using force plates and a motion capture system. Reflective markers were placed on lower extremity segments, as well as the pelvis and spine. Following anatomical calibration, participants performed the task until at least three good trials were obtained. Five kinetic variables pertaining to the Specific Aims of this study were calculated, including hip extension moments, hip limb symmetry, knee extension moments, knee limb symmetry, and joint work contribution. Statistical analyses were performed using the SPSS statistical software. Two-factor ANOVAs (group, limb) were performed for both hip and knee extension moments. Two one-factor ANOVAs (group) were performed with limb symmetry index with the hip and knee extensor moments as the outcome variable. A three-factor ANOVA (group, limb, joint) was performed to compare the relative joint work contributions of the hip, knee, and ankle. Seven kinetic variables outside of the Specific Aims of this study were also calculated in Excel to provide context for interpreting the results. Results: Statistically significant differences were found for all variables pertaining to the Specific Aims, except the joint work contribution. Statistically significant differences were also present in five of the variables collected outside of the Specific Aims. Conclusion: This study aimed to examine the three-dimensional kinetics of the hip, knee, and ankle joints during a dynamic double legged double hop task in individuals who have undergone ACL reconstruction and healthy controls. Statistical significance was found for the following variables: hip extension moments, hip limb symmetry, knee extension moments, knee limb symmetry, joint work, combined extensor moment at landing, combined extensor moment at take-off, peak knee angles, peak ankle angles, and ankle limb symmetry. These findings highlight the complexity of movement patterns in dynamic bilateral tasks in individuals who have undergone ACL reconstruction and suggest that the current return to play testing battery may overestimate or underestimate the functional capacity of the lower limb during the rehabilitation process
From BOBcat to Bursts: Multi-Messenger Constraints on Supermassive Black Holes and Binaries
Get PDFSupermassive black hole binaries (SMBHBs) are a natural consequence of hierarchical galaxy formation and evolution. When galaxies merge, their central supermassive black holes (SMBHs) are expected to form bound pairs that evolve from kiloparsec to sub-parsec separations under the influence of dynamical friction, stellar scattering, and gas dynamics. Ultimately, these SMBHs reach the regime where gravitational wave emission dominates and drives the final inspiral and coalescence. Understanding the formation, evolution, and observational signatures of SMBHBs is critical to advancing multi-messenger astrophysics, particularly in the era of pulsar timing arrays (PTAs) and the upcoming Laser Interferometer Space Antenna (LISA), which opens new windows into gravitational wave astronomy.
This dissertation explores the diverse range of electromagnetic signatures associated with SMBHBs, particularly in active galactic nuclei (AGN). These signatures include periodic photometric variability due to Doppler boosting or disk perturbations, dual or offset AGN activity, Doppler-shifted broad emission lines indicating orbital motion, precessing jets, and features tied to binary-induced accretion dynamics. These electromagnetic tracers serve as vital tools for identifying SMBHB candidates and correlating them with gravitational wave detections.
A key contribution of this work is the creation of a curated database of published peer-reviewed SMBHB candidate papers, which compiles observational evidence, classification criteria, and binary parameters for each binary system. This database serves as a resource for researchers to assess the robustness of SMBHB claims, identify trends in detection methods, and prioritize targets for multi-wavelength and gravitational wave follow-up. It provides a foundation for future population studies, model validation, and coordinated observational campaigns. This dissertation highlights the use of such a database through the exploration of gravitational waves for a subset of candidates from the database. Furthermore, this dissertation incorporates fast radio burst (FRB) X-ray observations to estimate the black hole mass in a candidate AGN progenitor. These observations underscore the growing importance of transient and high-energy astrophysics in informing studies of SMBHBs.
This work seeks to enhance our ability to detect, interpret, and contextualize SMBHBs using both electromagnetic and gravitational wave observations. Gaining deeper insight into SMBHBs is key to unraveling the mysteries of black hole formation and long-term evolution. This work aims to help lay critical groundwork for the next generation of multi-messenger discoveries
Capillary Electrophoresis Analyses Using Ultraviolet Detection and Novel Mass Spectrometry Interfaces for the Characterization of Small Molecules and Nanoparticles of Pharmaceutical Interest
No full textCapillary electrophoresis (CE) coupled to mass spectrometry (MS) offers a powerful analytical platform that unites high-efficiency separation with molecular-level identification. Despite its potential, limitations in interfacing and usability have constrained the widespread application of CE-MS. This thesis presents methodological advancements to enhance CE-based analysis through innovative interfacing, automation, and application to both small molecules and nanoparticle vaccine formulations. First, a nanoflow sheath CE-VSSI-MS interface is developed to overcome the limitations associated with flow-dependent ionization, enabling the use of narrow-bore capillaries, high separation voltages, and flexible pH conditions. This configuration effectively separated and detected diverse analytes, including β-blockers, amino acids, and nonsteroidal anti-inflammatory drugs across nanomolar to micromolar concentrations using both normal and reversed polarity modes. Building on this, a dual-function CE-VSSI-MS platform is fabricated to integrate ionization and make-up flow into a compact, user-friendly interface that supports the automation of commercial Beckman Coulter P/ACE™ MDQ. The analytical performance of this novel configuration is validated using small molecules under near-neutral and acidic pH. Moreover, this interface is employed to detect biologically relevant peptides, including transferrin digestion products and Huntington’s disease-associated peptides, enabling detection of peptide oligomers that are not observable with conventional CE-UV detection. Recognizing the growing importance of nanoparticle-based biopharmaceuticals, the scope of this work is extended to vaccine analysis using CE with UV detection. A robust capillary zone electrophoresis (CZE) method is developed and validated according to ICH Q2 guidelines for the simultaneous quantification of Human Papillomavirus (HPV) Virus-Like Particles (VLPs) and squalene nano-emulsion (SNE) adjuvants. These are two heterogeneous nanoparticles with similar sizes but distinct physicochemical properties. Utilizing the charge-to-size separation mechanism, the method achieved excellent linearity, accuracy, and precision with minimal sample preparation and demonstrated applicability for broader nanoparticle–adjuvant systems. Together, these studies demonstrate the versatility and analytical power of CE-based platforms, whether coupled with mass spectrometry or UV detection, for analysis of pharmaceutical small molecules and complex vaccine nanoparticle mixtures
Coarse Salary-Setting and Behavioral Teams
Get PDFAmong National Hockey League (NHL) player contracts signed in 2011-24, over 38% are divisible by $100,000. This paper shows that the bunching of NHL contracts at round numbers is partly driven by team coarse wage-setting. I first show that teams with more coarse contracts have worse team performance. Then, my empirical results validate two model predictions derived from a wage-setting model in which optimization costs lead to the adoption of rounded wages. With a novel measure of management quality, I document a negative relationship between management quality and coarse salary-setting. Next, I find that coarse salary-setting is associated with higher pay inequality. Finally, I do not identify spillover effects of changes in minimum salaries on coarse salary-setting as documented in the previous literature
The Rise and Fall of U.S. Support for Operation Condor
Get PDFOperation Condor (Condor) was a transnational terror network set up by six military dictatorships in South America with the support of the United States’ Central Intelligence Agency (CIA) in order to kill and silence dissidents in the nineteen seventies. Research on Condor tends to focus on the individual dictatorships involved; the relationship between those dictatorships and the United States has been comparatively understudied. Unlike in other Cold War battlegrounds, the human rights violations committed by the Condor dictatorships caused Congress to take action, investigate the CIA, and tie human rights requirements to U.S. foreign assistance to the region
Root coverage outcomes in mandibular anterior teeth: A retrospective analysis of GPST vs traditional methods.
No full textAim: The aim of this study was to evaluate and compare, between techniques, recession coverage outcomes after soft tissue grafting procedures using bilaminar techniques around natural teeth in the mandibular anterior region. Materials and Methods: This is a retrospective comparative study. 61 patients with 99 sites were treated using the Gingival Pedicle with Split thickness Tunnel technique-GPST (test group), or using either CAF/Tunnel/Vista techniques (control group). Outcomes were evaluated at 6 weeks duration or longer. Primary outcome was complete root coverage (CRC) percentage. Secondary outcomes were mean root coverage (MRC) percentage. Influence of factors such as the level of clinical training, recession type, single/multiple teeth treatment, presence or absence of frenum were also examined. All information was obtained through patient chart records and the statistical analysis was then performed. Results: Overall, compared to the control group, GPST was associated with higher odds of CRC (Odds ratio: 2.04). Compared to CAF alone, GPST was associated with an Odds ratio of 0.88. However, when compared to tunnel technique, GPST was associated with better CRC chances, with an odds ratio of 2.63. For mean root coverage comparisons, GPST was associated with 1.28% higher mean root coverage when compared to other techniques; 6.08% lower mean root coverage compared to CAF; and 4.79% higher mean root coverage compared to the tunnel technique. Factors such as a higher level of clinical training, a lower RT category of recession, absence of an aberrant frenum, and single tooth recession site, were generally associated with better outcomes. Conclusions: GPST technique consistently performed better than the tunnel technique for treating mandibular anterior teeth recession
Finite Element Modeling and Experimental Characterization of Overmolded Gold-Palladium Composite Leads and their Mechanical Behavior under Cyclic Fatigue for Long-Term Implant Applications
Get PDFAuditory Nerve Interface (ANI) devices, currently in developmental stages, represent an emerging neuroprosthetic approach to restore hearing in severe sensorineural loss patients by directly stimulating the auditory nerve via the Utah Slanted Electrode Array (USEA). Conventional implant leads are comprised of multiple wires made from materials such as platinum-iridium and MP35N stainless steel that are overmolded in an insulative material. These materials are not possible to bond with to electrode array used in the ANI device, necessitating the evaluation of a new material like Au-Pd to ensure its functionality and durability under cyclic stresses. This gap necessitates characterization of alternative leads for ANI durability under cyclic stresses, aligned with standards such as ANSI/AAMI CI86 for cochlear implants. This research evaluates a helical gold-palladium (99% Au,1% Pd) alloy leads encapsulated in NuSil 4211 medical-grade silicone. Uniaxial tensile testing was conducted to examine the silicone\u27s nonlinear elastomeric properties through a Neo-Hookean model, which was imported into ANSYS finite element analysis of the stresses present in a 15˚bend. Finite element analysis revealed peak von mises stresses of 137 MPa in straight wires along the tensile portion, exceeding gold\u27s yield strength, versus 20-24 MPa in helical designs. Comparison with literature predictions of fatigue lifetimes of helical Au-Pd leads estimates 1,000,000 cycles through improved stress distribution. Optical imaging was compared to finite element analysis, with silicone strains aligning with simulated strains. In vitro cyclic fatigue tests in compliance with the CI86 standard issues 100,000 cycles of a 15˚bend at 2 Hz. Measurements of both prototype leads and ANI devices were monitored via electrical impedance below thresholds (120 Ω and 70 kΩ), with the ANI device was quantified via voltage matrices. No channel failures occurred despite pre-existing handling damage, confirming helical geometry\u27s resistance of fatigue and compliance with CI86 requirements. This characterization certifies Au-Pd helical wires as an effective lead for developmental ANI devices, potentially establishing a model for design improvement as well as validating safety toward clinical trials
What Does It All Mean? Differences in Self-Defining Memories Between Community and Adjudicated Youth
Get PDFIdentity development is driven in large part by self-defining memories, or memories though which we base our definition of who we are (Habermas & Bluck, 2000). In adolescence, cognitive skills are gained that allow us to make meaning, or learn lessons and gain insight, from self-defining memories (Bluck & Habermas, 2001; McLean & Thorne, 2003). To determine whether there are differences in their ability to make meaning from their self-defining memories, this study compares narratives of self-defining memories between community youth and adjudicated youth. Additionally, the ability to be specific in self-defining memory recollection may differ between these groups, which is explored in the present study. Male participants were recruited from a juvenile detention center and from the community (N = 63). All participants provided three self-defining memory narratives, which were coded for meaning making, memory specificity, and type of event recalled. Additionally, participants completed a measure of future identity. Between-group differences in meaning making, memory specificity, event type, and future identity were examined. Differences in dependent variables according to demographic variables including age, SES, education level, and race/ethnicity were also examined. Finally, a post hoc examination of the implications of mental health diagnoses (autism, ADHD, depression) on meaning making were explored. Significant and null results are reported and discussed, along with study limitations, future research directions, and implications for interventions supportive to adjudicated youth
