Master of Science

thesisThe objective of this study was to examine how emotional processing (i.e., understanding, acknowledging, and accepting emotions) moderated self-control (i.e., regulation of thoughts, emotion, and behavior) in explaining diabetes-specific self-regulation and metabolic control in adolescents with type 1 diabetes. Strong emotional processing was expected to confer regulatory benefit and promote adaptive outcomes, especially so for adolescents with poor self-control. General self-control capacity, and particularly self-control combined with emotional processing, may also underlie the relation of diabetes-specific management self-competence, negative affect, and adherence, and metabolic control. Self-report measures of self-control, emotional processing, diabetes management self-competence, diabetes-specific negative affect, adherence, and measured HbA1c were obtained from 137 adolescents with type 1 diabetes (M age = 13.48 years). Emotional processing significantly moderated the relation of self-control and metabolic control. Adolescents with high emotional processing were buffered from the effects of poor self-control. Adolescents with low self-control and low emotional processing had the poorest metabolic control. This interaction predicted metabolic control better than diabetes-specific self-regulatory constructs, and mediated the relations between those constructs and metabolic control. These findings suggest the importance of considering strength of emotional processing and self-control in the study of diabetes-specific self-regulation and health outcomes in adolescents with type 1 diabetes

Single-cell western blotting.

To measure cell-to-cell variation in protein-mediated functions, we developed an approach to conduct ∼10(3) concurrent single-cell western blots (scWesterns) in ∼4 h. A microscope slide supporting a 30-μm-thick photoactive polyacrylamide gel enables western blotting: settling of single cells into microwells, lysis in situ, gel electrophoresis, photoinitiated blotting to immobilize proteins and antibody probing. We applied this scWestern method to monitor single-cell differentiation of rat neural stem cells and responses to mitogen stimulation. The scWestern quantified target proteins even with off-target antibody binding, multiplexed to 11 protein targets per single cell with detection thresholds of <30,000 molecules, and supported analyses of low starting cell numbers (∼200) when integrated with FACS. The scWestern overcomes limitations of antibody fidelity and sensitivity in other single-cell protein analysis methods and constitutes a versatile tool for the study of complex cell populations at single-cell resolution

Exposures at Day Labor Corners: Using Existing Georeferenced Data to Describe Features of Urban Environments

PURPOSE: Latino day laborers are male immigrants from mainly Mexico and Central America who congregate at corners, that is, informal hiring sites, to solicit short-term employment. Studies describing the occupational environment of Latino day laborers traditionally measure jobsite exposures, not corner exposures. We sought to elucidate exposures at corners by describing their demographic, socioeconomic, occupational, business, built, and physical environmental characteristics and by comparing corner characteristics with other locations in a large urban county in Texas. METHODS: We used multiple publicly available data sets from the U.S. Census, local tax authority, Google\u27s Nearby Places Application Programming Interface, and Environmental Protection Agency at fine spatial scale to measure 34 characteristics of corners with matched comparison locations. RESULTS: Corners were located close to highways, high-traffic intersections, hardware and moving stores, and gas stations. Corners were in neighborhoods with large foreign-born and Latino populations, high rates of limited English proficiency, and high construction-sector employment. CONCLUSIONS: Publicly available data sources describe demographic, socioeconomic, occupational, business, built, and physical environment characteristics of urban environments at fine spatial scale. Using these data, we identified unique corner-based exposures experienced by day laborers. Future research is needed to understand how corner environments may influence health for this uniquely vulnerable population

‘I am free in my wheelchair but pain does have a say in it though’: The meaning and experience of quality of life when living with paraplegia and chronic pain

This study investigated how wheelchair-using individuals with paraplegia and chronic pain make sense of the factors associated with quality of life based on interviews using photo-elicitation and interpretative phenomenological analysis. Three superordinate themes emerged in the analysis: experiencing quality of life through the perception of self and identity, interpersonal relationships as facilitators and barriers to quality of life and life in a wheelchair: pain experience and management. Quality of life for those living with paraplegia and chronic pain is experienced as a complex interaction across several life domains. The use of photographs may improve the communication of pain-related experiences and understanding by healthcare staff

Shear localisation, strain partitioning and frictional melting in a debris avalanche generated by volcanic flank collapse

The Arequipa volcanic landslide deposit to the east of Arequipa (Peru) originated from the Pichu Pichu volcanic complex, covering an area ~200 km2. The debris avalanche deposit exhibits internal flow structures and basal pseudotachylytes. We present field, microstructural and chemical observations from slip surfaces below and within the deposit which show varying degrees of strain localisation. At one locality the basal shear zone is localised to a 1–2 cm thick, extremely sheared layer of mixed ultracataclasite and pseudotachylyte containing fragments of earlier frictional melts. Rheological modelling indicates brittle fragmentation of the melt may have occurred due to high strain rates, at velocities of >31 m s−1 and that frictional melting is unlikely to provide a mechanism for basal lubrication. Elsewhere, we observe a ~40 cm thick basal shear zone, overprinted by sub-parallel faults that truncate topological asperities to localise strain. We also observe shear zones within the avalanche deposit, suggesting that strain was partitioned. In conclusion, we find that deformation mechanisms fluctuated between cataclasis and frictional melting during emplacement of the volcanic debris avalanche; exhibiting strain partitioning and variable shear localisation, which, along with underlying topography, changed the resistance to flow and impacted runout distance

Frictional Behaviour, Wear and Comminution of Synthetic Porous Geomaterials

During shearing in geological environments, frictional processes, including the wear of sliding rock surfaces, control the nature of the slip events. Multiple studies focusing on natural samples have investigated the frictional behaviour of a large suite of geological materials. However, due to the varied and heterogeneous nature of geomaterials, the individual controls of material properties on friction and wear remain unconstrained. Here, we use variably porous synthetic glass samples (8, 19 and 30% porosity) to explore the frictional behaviour and development of wear in geomaterials at low normal stresses ( 641\ua0MPa). We propose that porosity provides an inherent roughness to material which wear and abrasion cannot smooth, allowing material at the pore margins to interact with the slip surface. This results in an increase in measured friction coefficient from <0.4 for 8% porosity, to <0.55 for 19% porosity and 0.6\u20130.8 for 30% porosity for the slip rates evaluated. For a given porosity, wear rate reduces with slip rate due to less asperity interaction time. At higher slip rates, samples also exhibit slip weakening behaviour, either due to evolution of the slipping zone or by the activation of temperature-dependent microphysical processes. However, heating rate and peak temperature may be reduced by rapid wear rates as frictional heating and wear compete. The higher wear rates and reduced heating rates of porous rocks during slip may delay the onset of thermally triggered dynamic weakening mechanisms such as flash heating, frictional melting and thermal pressurisation. Hence porosity, and the resultant friction coefficient, work, heating rate and wear rate, of materials can influence the dynamics of slip during such events as shallow crustal faulting or mass movements

Comparison of model-predicted and measured moment arms for the rotator cuff muscles

The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.clinbiomech.2007.02.001. © 2007. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Background The ability of mathematical models of the shoulder to accurately replicate physiological muscle moment arms is unknown. The purpose of this study was to compare model-predicted and experimentally measured moment arms for the rotator cuff muscles during arm elevation. Methods Moment arms obtained from six mathematical models and seven experimental studies were compared for the supraspinatus, infraspinatus, teres minor, and subscapularis for elevation in the scapular plane. Results All of the included models generated moment arms that generally fell within the range of experimentally measured data. Interpretation The quantitative agreement between model-predicted and experimentally measured moment arms supports the use of the included models for biomechanical shoulder analyses.National Institute of Healt

Ethnic Disparities in Early-Onset Gastric Cancer: a Population-Based Study in Texas and California

BACKGROUND: Incidence rates of gastric cancer are increasing in young adults (age \u3c50 \u3eyears), particularly among Hispanic persons. We estimated incidence rates of early-onset gastric cancer (EOGC) among Hispanic and non-Hispanic White persons by census tract poverty level and county-level metro/nonmetro residence. METHODS: We used population-based data from the California and Texas Cancer Registries from 1995 to 2016 to estimate age-adjusted incidence rates of EOGC among Hispanic and non-Hispanic White persons by year, sex, tumor stage, census tract poverty level, metro versus nonmetro county, and state. We used logistic regression models to identify factors associated with distant stage diagnosis. RESULTS: Of 3,047 persons diagnosed with EOGC, 73.2% were Hispanic White. Incidence rates were 1.29 [95% confidence interval (CI), 1.24-1.35] and 0.31 (95% CI, 0.29-0.33) per 100,000 Hispanic White and non-Hispanic White persons, respectively, with consistently higher incidence rates among Hispanic persons at all levels of poverty. There were no statistically significant associations between ethnicity and distant stage diagnosis in adjusted analysis. CONCLUSIONS: There are ethnic disparities in EOGC incidence rates that persist across poverty levels. IMPACT: EOGC incidence rates vary by ethnicity and poverty; these factors should be considered when assessing disease risk and targeting prevention efforts