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Constructing Optimism as Anticipatory Resilience: Enacting Resilience Processes Over Time Following Pandemic-Related Job Loss Predicts Optimism of Lessons Learned
No full textThe communication theory of resilience (CTR) conceptualizes resilience as both reactive (i.e., processes enacted in response to current disruption) and anticipatory (i.e., mindsets and resources cultivated proactively over time). To test CTR’s assumption that enacting resilience processes helps cultivate anticipatory resilience, U.S. adults who involuntarily lost their jobs during the COVID-19 pandemic were surveyed about their engagement in resilience processes in spring 2021 (wave 1), as well as two and four months later (waves 2 and 3). In the third wave, participants reported lessons they learned from experiencing job loss during a pandemic, and responses were rated for the degree to which their lessons expressed optimism. Self-reported enactment of CTR processes 2 and 4 months earlier predicted optimism in lessons learned at the final survey after controlling for social and material well-being. Findings extend CTR and have implications for supporting individuals and families experiencing disruption
Digging through the Galactic Graveyard: Chemistry and Ages of Dead Milky Way Satellite Galaxies
No full textCharacterizing Galactic sub-structures is crucial to understanding the assembly history and evolution of the Milky Way. To accomplish this, we need to identify and analyze the accreted sub-structures. With ESA Gaia and SDSS-IV/APOGEE, studies have been done to analyze the kinematics and chemical abundances, respectively. However, one challenge that still remains is deriving reliable ages for these sub-structures. We utilize the new [C/N]-Age relationship derived by the OCCAM team, which has recently been extended to the metal-poor regime, to probe stars within the sub-structures in the metallicity range -1.2 ≤ [Fe/H] ≤ +0.3 dex. This allows us to determine the ages of a greater number of stars within these sub-structures which paints a more coherent picture of the original galaxies that have been disrupted to form the Milky Way’s halo. Using the sample of halo sub-structures in Horta et al. (2023), we apply the newly extended calibration to determine ages of stars within these sub-structures and compare them to previous age estimates
As for me and my house
No full textAs for me and my house explores a domestic realm where a variety of materials and objects narrate the pictorial and spatial possibilities of this obscure world. Materials such as paper pulp, glazed ceramics, oil paint, and other sculptural materials are used to create a Tiffany lamp, a mischievous 6-pack of Lone Star Beer, a fountain of mysterious yellow liquid, and a lavender claw-foot tub who bleeds out of her own faucet. These anthropomorphized forms aid in examining the intersection of queerness, femininity, and the grotesque. Through this exhibition, Walker embarks on the journey of unpacking a more expansive vision of her identity, reflecting on her studio practice, material investigations, and personal research
A Comprehensive Study of Open Cluster Chemical Homogeneity Using APOGEE and Milky Way Mapper Abundances
No full textStars in an open cluster are assumed to have formed from a broadly homogeneous distribution of gas, implying that they should be chemically homogeneous. Quantifying the level to which open clusters are chemically homogeneous can therefore tell us about interstellar medium pollution and gas mixing in progenitor molecular clouds. Using Sloan Digital Sky Survey (SDSS)-V Milky Way Mapper and SDSS-IV Apache Point Observatory Galaxy Evolution Experiment DR17 abundances, we test this assumption by quantifying intrinsic chemical scatter in up to 20 different chemical abundances across 26 Milky Way open clusters. We find that we can place 3σ upper limits on open cluster homogeneity within 0.02 dex or less in the majority of elements, while for neutron capture elements, as well as those elements having weak lines, we place limits on their homogeneity within 0.2 dex. Finally, we find that giant stars in open clusters are ∼0.01 dex more homogeneous than a matched sample of field stars
Spiders as sentinels of mercury contamination in high arctic lentic systems and potential risk to arachnivorous birds
No full textDue to global atmospheric circulation of mercury, polar food webs are contaminated with detectable levels of mercury despite their remoteness. In aquatic systems, inorganic forms of mercury are methylated into the bioavailable and toxic form, methylmercury. The Arctic has an estimated 1.4x106 km2 of freshwater lakes and ponds, making monitoring efforts of where wildlife may be at risk of mercury exposure difficult. Common sentinels of aquatic Hg contamination in monitoring studies include dragonflies, fish, and spiders. However, only spiders are found consistently and at high abundance in Arctic ecosystems. Spiders are also consumed by nestling songbirds and therefore can also provide insight into the potential health risk mercury poses to arachnivorous birds. The objectives of the present study were to 1) determine if spiders are sentinels of freshwater Hg contamination in six Arctic lentic systems located in northwest Greenland and 2) to determine if Hg-contaminated spiders pose a health risk to arachnivorous birds. The average (± 1 SE) concentration of MeHg of P. glacialis from all lentic systems was 424.0 (± 28.4) ng/g (range: 212.9 to 897.9) dry weight (dw). We detected a significant main effect of leg length on spider tissue MeHg concentration (p = ≤ 0.001); spider tissue MeHg concentration was positively correlated with leg length at each site. We detected a significant leg length × site interaction effect (GLM, F5,21 = 4.4, p = 0.007) and we observed a significant positive relationship between riparian spider and aquatic insect tissue MeHg (linear regression, R2 = 0.75, p = 0.04). The results of this study suggest that shoreline spiders are sentinels of aquatic mercury contamination, providing evidence for their future use as sentinels of other aquatic systems in the Arctic. We also suggest that arachnivorous birds are at varying levels of risk from MeHg toxicity at six lentic systems in Northwest Greenland
A Tale of Winds and Tides: Characterizing the Properties of the Magellanic Stream
No full textGaseous debris expelled from the disk of a galaxy can form galactic winds. These winds can be pulled between galaxies due to gravitational interactions. One of the most prominent examples is the Magellanic Stream (MS): a trail of gaseous material flowing behind the Large Magellanic Cloud (LMC) likely extracted from the LMC’s galactic winds. To characterize the MS’s chemical properties, we probe along four O stellar sightlines using a combination of UV absorption-line spectroscopy from the Hubble Space Telescope’s Ultraviolet Legacy Library of Young Stars as Essential Standards (ULLYSES) program and H I emission-line data from the Galactic Australian Square Kilometre Array Pathfinder (GASKAP). We kinematically separated the LMC’s disk from the MS using two methods: calculating column density-weighted velocity centers and widths from position-velocity maps and performing Gaussian decomposition on the H I emission. We conclude part of the MS is kinematically between +238 ≤ vlsr ≤ +312 km/s by comparing the H I emission data with the UV absorption-line spectra. We selected low and intermediate-ionization species (e.g., Fe II, Fe III, S II, Ni II, Al II, and Al III) to explore column densities, doppler parameters, and central velocities. Our goal is to better understand the kinematics and ionization properties along the MS while helping to constrain its origin
Brown erasure: Mexican Americans and the teaching of history in cold war Texas
No full textThis dissertation explores the white architects of curriculum and instruction in Texas, the Mexican experience and resistance to that curriculum, and the effect on identity and community formation that schooling played on Mexican-origin students throughout the twentieth century. Through theorizing curriculum as the whole experience a child has at school from their relationships with their teachers to the school's relationship with the community, I posit that schooling has served as a mechanism to maintain white supremacist social hierarchies. I argue that local and state governments in the US have always used curriculum as a political tool; it is not neutral. Whether unilaterally deciding what knowledge is worth learning, sorting children by assumed future abilities, devaluing non-white cultures, and implementing assimilationist strategies into the classroom, educators and politicians have delivered curricula that reinforce America’s social order and silenced those deemed unworthy of inclusion. Altering and erasing the memory of historical events and people in textbooks and classrooms is a powerful tool in the creation and maintenance of white supremacy
Degree and Duration of Alkaline Phosphatase and Total Bilirubin Elevation Below Treatment Thresholds Predict Clinical Outcomes in Primary Biliary Cholangitis
No full textResearch Question: Among individuals diagnosed with PBC, do chronic elevations in ALP and TB below presently accepted guidelines correlate with an increased risk of adverse clinical outcomes (including time to the first occurrence of hospitalization, hospitalization for hepatic decompensation, liver transplant, or death) compared to PBC patients whose ALP and TB values align with or exceed accepted guidelines?Background and Significance: Primary biliary cholangitis (PBC) is an uncommon liver condition that mainly impacts women aged 50 and above. Existing models that evaluate the risk of disease advancement using biomarker values typically rely on individual baseline measurements. This study aimed to assess the influence of persistent elevations in alkaline phosphatase (ALP) and total bilirubin (TB) on clinical outcomes, even at levels lower than those indicated in current treatment guidelines.Materials and Methods: The population was patients diagnosed with PBC in the Komodo Health claims linked to two national laboratory databases. The primary analysis was a Cox regression treating proportion of time ALP exceeded specific thresholds of Upper Limit of Normal (ULN 1×; 1.2×; 1.5×; 1.67×; 2.0×) and TB thresholds below and above ULN (0.6×; 0.8×; 1.0×; 2.0×) on time to first occurrence of death, liver transplant or hospitalization for hepatic compensation.Results: 2,379 patients met all inclusion/exclusion criteria. Patients were predominantly female (85.3%) with a mean age of 63.3 years (SD=13.1). Median follow-up time was 2.2yrs (IQR: 1.1 – 3.9 years) with a mean of 7.2 ALP measures and 8.4 TB measures. For both ALP and TB, greater proportion of time spent above each threshold, and greater divergence from ULN for ALP and 0.6x ULN for TB, were associated with increased risk of a composite outcome event. A 10% increase in proportion of time ALP>ULN was associated with a statistically significant increased risk of event (HR=1.06; 95% CI=1.03, 1.09; p0.06xULN (HR=1.09; 95% CI=1.06, 1.12: pULN and TB>0.06xULN 100% of the time.Conclusion: These findings propose a shift in the management of PBC, moving away from a binary endpoint approach (e.g., 1.67×ULN) to a more nuanced understanding of the continuous relationship between biomarkers and outcomes. Physicians should evaluate both the absolute level of a biomarker and the duration it remains at that level when assessing the risk of disease progression and determining treatment strategies. Further research is essential to explore persistent elevations in alternative biomarkers, as well as in measures of fibrosis and inflammation
Neural and musculoskeletal adaptations to acute and chronic training in athletic populations
No full textIntroduction: Athletic populations are underrepresented in literature, with a majority of studies examining the effect of acute and chronic training in untrained individuals. The training adaptations gained following resistance or endurance training may alter performance, specifically, the inherent fatigue resistance observed in females. However, limited data exists examining sex differences in fatigue during dynamic muscle actions commonly performed during resistance training. Therefore, this dissertation examines neuromuscular responses between sexes during acute resistance exercise in resistance- and endurance-trained athletic populations. Additionally, this work identifies the musculoskeletal adaptations that occur across a year of training in Collegiate Division 1 football players.
Methods: Three studies were completed in highly trained, athletic populations, examining neuromuscular differences in males and females during acute training in the upper body and lower body, and musculoskeletal adaptations to chronic training in Collegiate Division I football players. The first study utilizes electromyography (EMG) to examine neuromuscular responses during acute resistance exercise and subsequent isometric force production of the elbow flexors in a resistance-trained population. The second study uses EMG and ultrasonography of the knee extensors and examines neuromuscular responses during acute resistance exercise and subsequent isometric force production in an endurance-trained population. The third study identifies musculoskeletal adaptations in Collegiate Division 1 football players across the 2023 year.
Results: At the same relative intensity (50% 1RM), resistance-trained females demonstrate statistically significant greater fatigue resistance in the elbow flexors, quantified by a greater number of repetitions performed (M: 48.3 ± 6.1; F: 64.9 ± 12.3), greater subsequent isometric strength maintenance (M: 69.8%; F: 76.1%), and greater relative biceps brachii EMG amplitude (M: 98.6 ± 31.1%; F: 125.8 ± 36.9%) compared to males. However, endurance-trained males and females demonstrate no difference in the number of repetitions performed (M: 69.3 ± 17.1; F: 72.6 ± 26.5) or subsequent isometric force produced (M: 86.6%; F: 88.1%) during knee extension. Despite the lack of performance differences, females demonstrate greater maintenance of relative rectus femoris EMG amplitude (M: 73.38 ± 6.39%; F: 93.23 ± 5.61%) compared to males during the knee extension task. Lastly, Division 1 Collegiate football players demonstrate significant changes in lean mass and fat-free mass index (FFMI), observing increases (177.0 ± 24.5 lbs; 24.1±2.1 kg/m2) and decreases (172.6 ± 25.3 lbs; 23.5 ± 2.3 kg/m2) that corresponds with increased or decreased training volume, respectively. This occurred without a significant change in body fat percentage (16.5 ± 7.4% to 17.2 ± 7.6%) or body weight (226.5 ± 48.5 lbs to 223.2 ± 49.3 lbs). However, bone mineral composition significantly increased (9.2 ± 1.2 lbs to 9.4 ± 1.3 lbs) and Achilles tendon echo intensity decreased (123.8 ± 15.7 a.u. to 99.64 ± 17.3 a.u.), while Achilles tendon thickness generally maintained size (0.47 ± 0.08 cm to 0.50 ± 0.06 cm) regardless of changes in training volume.
Conclusions: Sex differences in acute resistance training fatigue are more pronounced for the upper limbs compared to the lower limbs. Additionally, similar neuromuscular responses are observed between males and females for the knee extensors, unlike that shown for the elbow flexors. Collegiate Division 1 football players present significant lean mass changes due to alterations in training, demonstrating modifications in lean mass despite chronic training experience. This dissertation presents novel information regarding prior training experience on acute resistance training fatigue between males and females. Additionally, novel insights are shown for the effect of training over a year of collegiate football on musculoskeletal variables and emphasize the use of FFMI and Achilles tendon ultrasonography in collegiate football players. This data shows the neuromuscular and musculoskeletal responses to acute and chronic exercise training in athletic populations
Is a Pre-Operative UTI a Risk Factor for Post-Operative Wound Infection After Spinal Fusion?
No full textResearch Question: Is a pre-operative Urinary Tract Infection (UTI) a risk factor for post-operative wound infection after spinal fusion?Background and Significance: Spine surgery is a prevalent elective operation in the United States with the possibility of wound infection complications, and preoperatively, UTIs are common healthcare infections. Based on our review of current literature, very little evidence exists on the relationship between a positive pre-operative urinary tract infection and post-operative surgical site infections in patients undergoing spinal fusions. The purpose of this study is to evaluate the association between pre-operative urinary tract infections and post-operative surgical site infections within 30 days post operation.Materials and Methods: Following institutional review board (IRB) approval, this retrospective study examined 1,061 adult patients undergoing spinal fusions at a single high-volume center between 2019 and 2020. Patient clinical data such as principal diagnosis, presence of preoperative UTI, length of stay, readmission within thirty days, and the presence of wound infections was collected. Available data from patients’ electronic medical record was reviewed. Statistical Package for Social Sciences (SPSS) was used to perform independent sample t-tests to analyze numeric data and to perform Chi square tests of independence to analyze categorical data.Results: The incidence of pre-operative urinary tract infections was 7.5%, and the incidence of post-operative surgical site infections was 1.9%. Patients with a pre-operative urinary tract infection did not have a statistically significant increase in their risk of a developing surgical site infections after undergoing spinal fusion (p = 0.674).Conclusion: Our findings suggest that individuals with pre-operative urinary tract infections in the absence of bacteremia or sepsis may not benefit from postponing their spinal surgeries. However, prompt treatment with appropriate antibiotics is warranted