Bioculture Journal
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Tidal migration patterns moderate thermal risk in the intertidal snail Nucella ostrina
No full textThesis (Ph.D.)--University of Washington, 2016-03Physical environmental characteristics place limits on when and where organisms can survive, thereby shaping distributions and abundances of species. A thermal performance curve is often used to describe the organism’s performance along a thermal environmental gradient. Behavior can moderate temperatures experienced by an organism, increasing the time spent at optimal temperatures that confer high performance. Much of what is known about behavioral thermoregulation in ectotherms is based upon fast-moving animals, but organisms with relatively slow mobility, such as snails, may navigate their thermal environments on fundamentally different temporal or spatial scales. The intertidal zone has characteristics of both marine and terrestrial habitats, alternating between these two extremes multiple times per day. The timing of low tides has important consequences for the thermal environment; extreme temperatures depend on both aspect of the shoreline and the time during the day or night when the substrate is exposed. The predictability of these tidal influences can be exploited by mobile animals living in the intertidal zone to access food resources during times of reduced thermal risk. I examined foraging and migration behavior of the intertidal snail Nucella ostrina in controlled field experiments and surveys of natural habitats, and estimated snail body temperatures from physical thermal mimics deployed in the field. I assayed snail performance across a range of temperatures and modeled the effect that behavior would have upon the temperatures snails experienced, performance under current conditions, and performance in a simulated future climate with 2°C increase. I found that snails migrate into high shore foraging areas for only 2-4 d per two-week tidal cycle, then retreat to locations lower on shore and in thermal refuges such as cracks. This periodic cycle of behavior, foraging on days with nighttime low tides that are reliably cool, is seen under both manipulated conditions and in natural populations. Furthermore, when given the choice between different substrate aspects, this species selects the cooler microhabitat. These temporal and spatial patterns of behavior lead to a reduction in the time spent at high temperatures (30°C and above). Snail performance begins to decline above 30°C, taking several hours to recover from a 2 h duration of exposure to aerial temperature of 34°C and resulting in death for 75% of individuals at 35°C. Using a generalized model derived from observed snail behavior as a filter for temperatures experienced, I found that migratory behavior drastically decreases the exposure of N. ostrina to temperatures that cause reduced performance or death. Simulated climate change increases the frequency of high temperature events, but the benefit of migratory behavior is maintained. Selection of foraging time and location confers a thermal benefit to N. ostrina, reducing this snail’s risk of exposure to detrimental temperatures that frequently occur in its habitat. Climate change is unlikely to directly affect this species as it simply is not present at times and in places where high temperatures occur, however, several indirect effects should be considered. Slow animals may be thermoregulating on a different temporal or spatial scale than we are accustomed to examining for faster moving species
Latent and Lytic KSHV Infection Require Host Cell Metabolism
No full textThesis (Ph.D.)--University of Washington, 2016-06Viruses are obligate intracellular parasites that depend on host cell machinery for their production and spread. Host metabolism is dramatically altered by several viruses to provide metabolic intermediates for biosynthetic as well as bioenergetic precursors. Understanding how a virus establishes and depends on a specific metabolic signature is critical to revealing possible therapeutic targets of infected cells. In this thesis, I further examined metabolic alterations during infection with the oncogenic virus, Kaposi’s Sarcoma Associated Herpesvirus (KSHV). Like all herpesviruses, KSHV has both a latent and lytic viral life stage. Both latent and lytic cells are found in the KS tumor, therefore, I identified the metabolic alterations in both latent and lytic cells. Previous research indicated that glycolysis and fatty acid synthesis (FAS) were required during latent KSHV infection for the survival of latently infected endothelial cells. In Chapter 1, I confirmed the requirement for FAS during latent infection. After presenting the background (Chapter 1) and Methods (Chapter 2), in Chapter 3, I defined the critical role glutamine metabolism plays in endothelial cells infected with KSHV. I also identify the cellular mechanism by which glutamine addiction is established during latency. Finally, in Chapter 4, I demonstrated that glycolysis, glutamine metabolism, and FAS are all required for maximal infectious KSHV virion production in lytically replicating cells. We show that each of these metabolic pathways contribute to virus production at a different step in lytic replication. Therefore, this body of work provides evidence that both latent and lytic KSHV infection depend on central carbon metabolism. These data may support the development or improvement of clinical therapies that target these carbon utilization pathways, thereby treating all infected cells of the KS tumor
Conditioned Pain Modulation (CPM) Test: Reliability, Feasibility, and Normal Values
No full textThesis (Ph.D.)--University of Washington, 2016-09Pain is the common characteristic associated with conditions such as chronic headache, arthritis, herpes zoster, diabetic neuropathy, and temporomandibular joint disorders (TMD). Typically, nerve impulses produced peripherally by a stimulus travel centrally to the spinal cord and the brain stem where they are elaborated before they reach various regions in the cortex, resulting in pain perception. Impulses may go through a modulation process -through the endogenous pain inhibitory pathways in humans- where alterations of the pain signals lead to either their inhibition or enhancement before they reach the higher centers of the brain. Currently, the best way to assess the efficiency of endogenous pain inhibition in humans is by performing a test that assesses pain modulation. Pain modulation can occur by several mechanisms and previous work has shown that the application of a noxious stimulus in one part of the body can inhibit pain in another part of the body, presumably by activating the descending inhibitory pain system. This phenomenon was previously termed ‘Diffuse Noxious Inhibitory Control’ (DNIC), but recently the term Conditioned Pain Modulation (CPM) is recommended for humans. The laboratory assessment of CPM involves a subject rating the pain intensity of a “test stimulus” (TS), during and after the application of a second painful “conditioning stimulus” (CS) to a distant region of the body. However, the reliability of this test has been investigated only by a few studies, and questions remain unanswered about its reproducibility, as well as its feasibility. Different types of conditioning and test stimuli have been employed. Our systematic review has shown that using cold pressor test (CPT) as a CS is one of most efficient methods to induce CPM when combined with pressure pain threshold (PPT) test stimulus. Previous studies have shown that chronic pain is associated with decreased endogenous analgesia which is indicated by less efficient CPM. Only a few studies have explored the reliability of the CPM test to assess the alterations in pain modulation in chronic pain patients. As a diagnostic test, it is essential that any CPM assessment yields consistent and reliable results. Therefore, in this dissertation we aimed to: 1-Dedicate the 1st chapter to provide a background about suggested pain modulation mechanisms including CPM, and factors that may affect this phenomenon. 2-Report the reliability of the CPM assessment paradigm by performing a systematic review of published studies on this topic. One assessor searched multiple electronic databases including: PubMed, EMbase and Web of Science, from inception to December 2015 inclusive. Inclusion criteria were comprised of original research, human subjects, and CPM tested identically at least twice with at least a 60 minutes interval between testing sessions. The main outcome was reliability. Reliability of CPM was reported as the Intra-class Correlation Coefficient (ICC), Coefficient of Variation (CV), and Coefficient of Repeatability (CR). 3-Assess the reliability of CPM through intra-session reliability and inter-session reliability. Healthy volunteers were tested three times (three visits) within a two-week period; each visit included two test sessions. In each session, PPT was performed identically on the test sites of the dominant side of the body in a non-overlapping fashion: the masseter muscle (side of the face), hand (thenar eminence), and foot (dorsum of the foot) three times. The PPT (the TS) was applied during and before the CPT (the CS) to calculate the CPM value. The CPM test stability was assessed by assessing the change in CPM scores from the baseline visit to the end of the follow-up visit. 4- The development of CPM normal values and its relationship at three body sites by age/gender. The difference between PPT values before and during the CPT is the magnitude of CPM. We aimed to determine the relationships between CPM at three body sites and age/gender in a healthy population, and second, to begin the development of a normative database for CPM. Specifically, the mean, median, lowest and highest pain inhibition scores were described separately for males, females, younger, middle and older age individuals, and by the anatomical sites of the pain stimulus – foot, hand and face. 5-Measure feasibility of clinical CPM testing: patient experience, and any adverse events. Although subjects were tested multiple times during each testing session, the proposed actual test procedure in the clinic is the PPT at one of the three tested sites during and before the CPT. Subjects answered a brief post-testing questionnaire that included questions on their tolerance for the test, the perceived safety of the test, as well as any experienced side effects. From the totality of our findings, our final recommendation for a reliable and feasible clinical CPM testing protocol includes performing the test on the hand, employing PPT using a manual algometer as a TS applied to the dominant hand, and CPT as a CS applied to the non- dominant hand. We recommend performing the test in the form of three rounds of PPT with 20s in between before CPT on the dominant hand, followed by immersion of non-dominant hand in cold water (CPT) at temperature of 5-7oC. When pain from CPT reaches 7 out of 10 according to numerical pain scale- where 0 is no pain and 10 is severe pain, the PPT should be applied simultaneously during the CS at this point while the non-dominant hand remaining in the cold water. At the beginning of the visit, we recommend performing a training session of the pain tests (CPT and PPT) on the volunteer’s hand 5 minutes before starting the testing session
A Survey Study Examining Teachers’ Perceptions in Teaching Refugee and Immigrant Students
No full textThesis (Ph.D.)--University of Washington, 2016-06There is limited research around best practices in working with refugee and immigrant students. Since teachers spend the majority of the school day with students, their insights about how best to serve these populations of children and adolescents is critical. This dissertation study conducted an online survey study with 139 elementary school general education teachers in a large urban school district to examine teacher beliefs and attitudes about the following factors in meeting the needs of refugee and immigrant children: teachers’ perceived self-efficacy, attitudes toward implementing new and innovative practices, cultural competency, prior preparation and overall competency, and perceptions about the needs of refugee and immigrant students. Results indicate that overall, teachers feel confident, culturally competent, and are open to implementing practices to serve refugee and immigrant students; the majority of teachers reported that they didn’t think that refugee and immigrant students have unique needs, which conflicts with current research; only minority status was found to be a unique predictor of beliefs around student needs. Implications and future research are discussed
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No full textA journal of commercial voyages and domestic life on the Tigris River -- Title page for diary series.Newbook Digital Text
We Can’t Breathe: Affective and Psychophysiological Reactivity of Vicarious Discrimination
No full textThesis (Master's)--University of Washington, 2016-12Many high-profile incidents of police brutality against African Americans have catalyzed racial tension in police-community relations. While these current events are undoubtedly harmful for the individuals directly affected, how might they shape the health and well-being of Americans at large, who experience perceived acts of discrimination vicariously through news and social media? While connected to cardiovascular recording equipment, 84 White and 67 African American participants were randomly assigned to read and give a speech about either police brutality or car accidents that harmed African Americans. Participants also completed several positive and negative affect assessments throughout the study. Participants in the police brutality condition experienced increased reactivity in heart rate, pre-ejection period, systolic blood pressure, and respiratory sinus arrhythmia compared to participants in the car accidents condition. For systolic blood pressure, this condition effect was stronger among African Americans than Whites. Additionally, participants in the police brutality condition reported greater affective reactivity, both positive and negative, compared to participants in the control condition, and these effects were stronger among African Americans than Whites. The findings shed light on how vicarious discrimination impacts stress pathways of both White and African Americans who are not directly targeted by these incidents and have implications for physical and mental health
Understanding near Fermi-level electronic structure through x-ray emission spectroscopy
No full textThesis (Ph.D.)--University of Washington, 2016-08Atomic and molecular chemical properties are largely determined by the electronic structure of near Fermi-level states. Determining this structure is therefore one of the central tasks in materials characterization and development. In the work of this dissertation I explore the capabilities and limitations of non-resonant x-ray emission spectroscopy (NXES) as an analytical technique aimed at addressing these issues. To this end, I report the development of novel laboratory- and synchrotron-based instrumentation for the study of transition metal and lanthanide compounds. One of the primary results of this research thrust is increased accessibility and throughput, making NXES measurements a more viable option in routine and research-grade materials study. Using experimental data obtained from these spectrometers, I evaluate current state-of-the-art theory in terms of modeling valence structure in ambient transition-metal complexes. Additionally, I use NXES to elucidate the evolving 4f-electronic structure in the early light lanthanides under pressure. In particular these results show a persistent 4f-moment across certain volume collapse transitions in Cerium and Praseodymium, thus helping settle a long-standing debate about the nature of volume collapse
Safer Conception Among HIV-1 Sero-Discordant Couples in East Africa: Understanding Knowledge, Attitudes, and Experiences
No full textThesis (Master's)--University of Washington, 2016-06Context: Supporting people affected by HIV-1 in achieving their reproductive goals while minimizing the risk of HIV-1 transmission is a public health imperative. Background: For HIV-1 serodiscordant couples, HIV-1 exposure and risk of transmission to the uninfected partner and unborn children is heightened during pregnancy attempts but safer conception strategies can mitigate risk. Understanding couples’ choices and experiences with safer conception can be useful for programmatic recommendations as safer conception programs are scaled up. Methods: 1013 high-risk, heterosexual HIV-1 serodiscordant couples from Kenya and Uganda were followed for two years in an open-label delivery study of integrated pre-exposure prophylaxis (PrEP) and antiretroviral therapy (ART), the Partners Demonstration Project. Annually, we assessed participant experience with safer conception strategies. Multivariate logistic regression was used to characterize women who reported ever having used a safer conception strategy during their first annual visit. Results: 859 couples were included in analysis. 66% of couples had HIV-infected women and 86% desired future children. The median age for women was 27 (interquartile range: 23-32). At the first annual visit, 32% of women reported use of a safer conception strategy ever in their life: 14% reported using ART, 16% PrEP, 3% self-insemination, and 2% STI treatment. Women who reported discussing their fertility desires with their male partners (adjusted odds ratio (aOR) = 1.91, 95% confidence interval (CI) 1.26-2.589), had no living children at the time of study enrollment (aOR = 1.71, 95% CI 1.14-2.57), and were HIV-uninfected (aOR = 1.56, 95% CI 1.11-2.20) were more likely to report having used at least one safer conception strategy. Conclusions: HIV-1 prevention counseling for serodiscordant couples should integrate opportunities for couples to share their fertility desires and discuss preferences for safer conception strategies
Evaluation of a Quality Improvement (QI) Intervention for Maternal, Newborn, and Child Health (MNCH) in Colombia: The Mil Días Intervention of SINERGIAS in the Department of Bolívar
No full textThesis (Master's)--University of Washington, 2016-06Initiated in 2012, the Mejoramiento de la calidad de la atención a gestantes, niñas y niños en sus primeros mil días (Mil Días) intervention is a strategy for quality improvement (QI) of maternal, child, and newborn health (MNCH) across 6 departments of Colombia. In the department of Bolívar, Mil Días is implemented in 25 health facilities across 12 municipalities. A time series analysis was conducted to determine whether or not contextual factors affect the rate of QI of antenatal care (ANC) among health facilities in Bolívar targeted by the Mil Días intervention. Multivariate linear regression analysis was used to examine relationships between predictors of interest and ANC performance over time. Important covariates included type of health facility (private or public), municipality level percentage of households with unsatisfied basic needs, number of health facilities per 100,000 municipal inhabitants, and MNCH patient volume per health facility. Findings were that quality of ANC, as measured by mean ANC performance scores or average rates of ANC indicators, increased over the implementation of Mil Días. Multivariate linear regression modeling demonstrated that health facility type was a significant predictor of the rate of QI of ANC, with public facilities showing an increased rate of QI as compared to private health facilities. This evaluation of Mil Días provides evidence of the importance of contextual influence on QI intervention results. Future studies examining program context ought to be conducted to inform QI strategies for the implementation of MNCH and related health services
Wavering into Capitalism: The Politics of Sustenance in North Korea
No full textIn the 1990s, a catastrophic famine engrossed North Korea. The famine not only claimed thousands of innocent lives but also the social, economic and political principles which had governed the nation since its founding. This paper contends that the famine engendered the rise of a rights-consciousness among North Korean working class citizens. In particular, the famine compelled the rise of bottom-up markets among common North Koreans, as the state failed to uphold its end of caloric compact, which then radically shifted the moral frameworks of the people. The nature in which these frameworks shifted is the focus of my paper. Chronicling the market protests which transpired during the late 2000s, this paper unveils the emergence of a novel constellation of power between the private citizen and the state in consequence of the markets engendering a rights-consciousness