PHYSIOLOGICAL, ECOLOGICAL, AND MICROBIAL FACTORS SHAPING THERMAL TOLERANCE AND PERFORMANCE IN ECTOTHERMIC VERTEBRATES

Temperature represents a major driving force in biology as it influences essential functions across multiple levels of biological organization. The role of temperature is especially important for ectothermic animals, whose biotic processes are dependent on both body and environmental temperature. Assessing the relationship between temperature and organismal performance represents an important research direction as temperatures continue to warm under anthropogenic climate change. Chapters two and three are focused on a recently colonized population of the invasive Mediterranean House Geckos at the northern edge of their invasion front. These chapters examine the ecological and physiological factors that enable these lizards to persist in a cooler and more temperate environment than their native range. The thermal breadth of a reptile greatly influences its ability to tolerate a thermally variable environment, particularly when environmental options are limited for behavioral thermoregulation. These chapters explore the thermal performance of this species, and the results show that the eurythermality of these geckos promotes their rapid colonization of novel environments despite experiencing prolonged periods of cool temperatures. Chapters four, five, and six, by contrast, shift focus to larval amphibians to explore the constraints and factors underlying plasticity in acclimation to temperature extremes. As habitats continue to warm with climate change, ectotherms with limited capacity to thermoregulate, such as larval amphibians in shallow ponds, will be under a heightened threat of heat stress and mortality. Resultantly, identifying different factors that can increase organismal heat tolerance would reduce the risk of overheating and promote survival. Chapters four, five, and six explore this topic by measuring the critical thermal maximum (CTmax) of larval wood frogs. Chapter four focuses on the tradeoff between basal CTmax and plasticity of CTmax and its consequences for how a larval anuran responds to an acute heat shock. Chapter five examines the role a viral pathogen, ranavirus, has on larval CTmax. Surprisingly, a lethal dose of ranavirus did not reduce CTmax which goes against the common pattern of pathogenic infections lowering host heat tolerance. Lastly, chapter six explores the relationship between the gut microbiota and host CTmax with a particular focus on cross-species microbiota transplants. In line with our prediction, transplanting the gut microbiota of a heat-tolerant donor species promoted greater CTmax in the heat-sensitive recipient species

A comparison of faculty and administrator perceptions of the merger of Kentucky\u27s community colleges and vocational/technical institutes.

One of the most nationally-recognized, two-year legislative reform initiatives in the U.S. began in Kentucky with the passage of the Kentucky Postsecondary Education Improvement Act of 1997 (HB1). This exploratory, cross-sectional, correlational study was administered at the 10-year anniversary of the HB1-legislated formation of the Kentucky Community and Technical College System (KCTCS), which originally combined 13 community colleges formerly governed by the University of Kentucky and 25 vocational/technical institutes previously governed by the Kentucky Cabinet for Workforce Development. This dissertation examined faculty and administrator perceptions of the merger of Kentucky\u27s community colleges and vocational/technical institutes that resulted from HB1. Two research questions guided the study. The first sought to determine whether significant differences in perceptions of merger were found between Kentucky Community and Technical College System (KCTCS) administrators and faculty. The second research question explored that, if there was a difference between the perceptions of the two groups concerning merger, could that difference be explained through five control variables which were gleaned from the research literature: (a) type of institutional decision-making, (b) depth of merger implementation, (c) level of involvement in merger initiatives, (d) internal versus external motivation for reform initiatives that led to merger, and (e) level of support for state postsecondary education reform initiatives that led to merger. A survey instrument was designed using information gathered from a thorough literature review. A panel of experts validated the instrument. The survey instruments were mailed to a stratified random sample of faculty ( n = 1,497) and all administrators ( N = 195) of the 16 public two-year colleges that form KCTCS. A total of 569 faculty and administrators returned completed, usable surveys and became the sample for the study. The 33.7 percent total return rate for this study was consistent within the acceptable range described in the research literature. The results of the study suggested that administrators maintained a more positive view of the merger than faculty. A one-way analysis of variance (ANOVA) was used to test the null hypothesis for the first question that there was no difference in the perception of merger, with Perception of Merger as the dependent variable and respondent status, faculty or administrator, as the independent variables. Administrators had a significantly higher mean score than faculty; therefore, the null hypothesis was rejected. Administrators maintained significantly more positive perceptions of the merger compared to faculty. For the second research question, a multivariate analysis of variance (MANOVA) was performed with the six indices of perception, type, depth, support, involvement, and motivation as dependent variables. The MANOVA confirmed that the administrators had significantly higher scale mean scores than faculty. A regression analysis was conducted to determine the degree of the relationship between the dependent variable, Perception of Merger, and the five control variables. The control variable with the strongest correlation for the dependent variable, Perception of Merger, was Level of Support for State Postsecondary Education Reform Initiatives That Led to Merger. All five control variables were significantly and positively associated with the dependent variable, Perception of Merger. Approximately 74% of the variance was predicted by the control variables. Two thematic constructs or clusters emerged from the data collected from administrators offering open-ended comments: (a) increased educational access and attainment--viewed as a positive result of merger, and (b) growth of the KCTCS Central Office and bureaucracy--viewed as a negative result of merger. Overall, administrators offered 31 positive comments regarding the merger and 42 negative comments. Two positive thematic constructs or clusters emerged from the data collected from faculty offering open-ended comments: (a) increased educational access and attainment and (b) improved technical training--both viewed as positive results of merger. Additionally, 15 negative themes emerged: (a) growth of the KCTCS Central Office and bureaucracy, (b) too many administrators, (c) negative impact on technical colleges, (d) the KCTCS President\u27s salary and benefits package, (e) lowered academic standards and declining quality of instruction, (f) negative impact on community colleges, (g) top-down management style, (h) differences of cultures/missions, (i) too much emphasis on enrollment numbers, (j) decline of general education transfer program, (k) rising tuition, (l) lack of local college autonomy, (m) loss of faculty authority and influence in college governance, (n) politically-motivated reforms, and (o) the move from a higher education model to a business model. Overall, faculty made 52 positive comments on the merger and 308 negative comments. The findings will potentially benefit community and technical college leaders, stakeholders, strategic planners, and state higher education boards (particularly those considering a similar merger process or implementing institutional changes that impact organizational culture). Understanding faculty and administrator perceptual differences--as well as identifying the conditions under which successful postsecondary education reforms may thrive--is an important element in guiding successful mergers and organizational change

Viscometric behavior of dilute dewaxed base oil-polymer solutions over a wide temperature range.

Four polymers were dissolved in a dewaxed base oil to concentrations of 0.1, 0.2, 0.3, 0.5, and 0.7% by mass to determine their potential as viscosity index improvers (VIIs). The polymers employed in this study included a hydrogenated diene copolymer, a dispersant olefin copolymer, an olefin copolymer, and polymethacrylate. Kinematic viscosities and densities of the base oil and dilute-polymer solutions were measured at $-25,-20,-10$, 0, 10, 20, 40, 60, 80, 100, 120, and 150\sp\circC. Since it was not possible to measure the densities at $-30,-15,-5$, and 5\sp\circC, only the kinematic viscosities were recorded. Relative and specific viscosities of dilute-polymer solutions were plotted against concentration and temperature, respectively to evaluate the polymeric influence on the viscometric properties of each system. Intrinsic viscosity was used to give a measure of the polymer\u27s ability to increase viscosity of the oil at infinite dilution. The hydrogenated diene copolymer, dispersant olefin copolymer, and olefin copolymer exhibited an increasing loss of fluidity below the cloud point. At a similar temperature the polymethacrylate did not show any significant loss of fluidity. This proves that this change in the viscometric properties is a polymer-oil dependent interaction. The olefin copolymer yielded the greatest overall thickening. The polymethacrylate was the only polymer to exhibit an increasing contribution to viscosity with increasing temperature, and also some pour point depression at -25\sp\circC. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1997 .W365. Source: Masters Abstracts International, Volume: 37-01, page: 0333. Adviser: A. A. Asfour. Thesis (M.A.Sc.)--University of Windsor (Canada), 1997

Preliminary Report on the Behavior of U-Pb Zircon and K-Ar Systems in Polymetamorphosed Ophiolitic Rocks and Batholithic Rocks, Southwestern Sierra Nevada Foothills, California

Ophiolitic rocks of the southwest Sierra Nevada foothills form part of the western metamorphic wall of the Sierra Nevada batholith (fig. 1). Geochronological studies were undertaken to determine: (1) The igneous petrogenetic age of the ophiolite; (2) The age of a prebatholith dynamic greenschist to amphibolite facies metamorphic event experienced by the ophiolite; and (3) The emplacement ages of the batholithic rocks. Geochronological work was interfaced with detailed structural and petrologic studies. A summary of the geochronological data is given in figure 2

Methyl rotor dependent vibrational interactions in toluene

The methyl rotor dependence of a three state Fermi resonance in S1 toluene at ∼460 cm−1 has been investigated using two-dimensional laser induced fluorescence. An earlier time-resolved study has shown the Fermi resonance levels to have different energy spacings at the two lowest methyl rotor states, m = 0 and 1. The overlapped m = 0 and 1 spectral features have been separated to provide direct spectral evidence for the m dependence of the resonance. The resonance has been probed at m = 3a″1 for the first time and found to be absent, providing further evidence for a large change in the interaction with m. Deperturbing the resonance at m = 0 and 1 reveals that the m dependence arises through differences in the separations of the “zero-order,” locally coupled states. It is shown that this is the result of the local “zero-order” states being perturbed by long-range torsion-vibration coupling that shifts their energy by small amounts. The m dependence of the shifts arises from the Δm = ±3n (n = 1, 2, …) coupling selection rule associated with torsion-rotation coupling in combination with the m2 scaling of the rotor energies, which changes the ΔE for the interaction for each m. There is also an increase in the number of states that can couple to m = 1 compared with m = 0. Consideration of the magnitude of reported torsion-rotation coupling constants suggests that this effect is likely to be pervasive in molecules with methyl rotors

The toluene-Ar complex: S0 and S1 van der Waals modes, changes to methyl rotation, and torsion-van der Waals vibration coupling

The methyl rotor and van der Waals vibrational levels in the S1 and S0 states of toluene-Ar have been investigated by the technique of two-dimensional laser induced fluorescence (2D-LIF). The S0 van der Waals and methyl rotor levels are reported for the first time, while improved S1 values are presented. The correlations seen in the 2D-LIF images between the S0 and S1 states lead to a reassignment of key features in the S1 ← S0 excitation spectrum. This reassignment reveals that there are significant changes in the methyl rotor levels in the complex compared with those in bare toluene, particularly at low m. The observed rotor energies are explained by the introduction of a three-fold, V3, term in the torsion potential (this term is zero in toluene) and a reduction in the height of the six-fold, V6, barriers in S0 and S1 from their values in bare toluene. The V3 term is larger in magnitude than the V6 term in both S0 and S1. The constants determined are |V3(S1)| = 33.4 ± 1.0 cm−1, |V3(S0)| = 20.0 ± 1.0 cm−1, V6(S1) = −10.7 ± 1.0 cm−1, and V6(S0) = −1.7 ± 1.0 cm−1. The methyl rotor is also found to couple with van der Waals vibration; specifically, the m″ = 2 rotor state couples with the combination level involving one quantum of the long axis bend and m″ = 1. The coupling constant is determined to be 1.9 cm−1, which is small compared with the values typically reported for torsion-vibration coupling involving ring modes

Impact of time to appropriate therapy on mortality in patients with vancomycin-intermediate Staphylococcus aureus infection

Despite the increasing incidence of vancomycin-intermediate Staphylococcus aureus (VISA) infections, few studies have examined the impact of delay in receipt of appropriate antimicrobial therapy on outcomes in VISA patients. We examined the effects of timing of appropriate antimicrobial therapy in a cohort of patients with sterile-site methicillin-resistant S. aureus (MRSA) and VISA infections. In this single-center, retrospective cohort study, we identified all patients with MRSA or VISA sterile-site infections from June 2009 to February 2015. Clinical outcomes were compared according to MRSA/VISA classification, demographics, comorbidities, and antimicrobial treatment. Thirty-day all-cause mortality was modeled with Kaplan-Meier curves. Multivariate logistic regression analysis (MVLRA) was used to determine odds ratios for mortality. We identified 354 patients with MRSA (n = 267) or VISA (n = 87) sterile-site infection. Fifty-five patients (15.5%) were nonsurvivors. Factors associated with mortality in MVLRA included pneumonia, unknown source of infection, acute physiology and chronic health evaluation (APACHE) II score, solid-organ malignancy, and admission from skilled care facilities. Time to appropriate antimicrobial therapy was not significantly associated with outcome. Presence of a VISA infection compared to that of a non-VISA S. aureus infection did not result in excess mortality. Linezolid use was a risk for mortality in patients with APACHE II scores of ≥14. Our results suggest that empirical vancomycin use in patients with VISA infections does not result in excess mortality. Future studies should (i) include larger numbers of patients with VISA infections to confirm the findings presented here and (ii) determine the optimal antibiotic therapy for critically ill patients with MRSA and VISA infections

Improved Way to Affix IV Components to Gurneys from Operating Tables

The current issue in the process of transporting a patient from the operating room (OR) to the intensive care unit (ICU) is the risks involved with the IV stand being top-heavy due to two or three IV pumps weighing approximately 15 pounds each. This can lead to injury to the patient, or other personnel, if an instance occurred where the IV stand were to tip over. Having a single person to manage both the IV stand and gurney during transport can increase this risk. To remedy these problems, the project team established the goals of developing a working prototype, testing and evaluating its feasibility, and demonstrating the use of the design to the sponsor. The constraints addressed in completing the design were safety (ex. maintaining access to patient’s head), a quick attach/release function, manufacturability, practicality, cost, and ease of use. The safety of those involved is of utmost importance during this process. To solve these issues two separate solutions were developed in conjunction with two common approaches to affixing IV poles. One solution uses an IV stand on a set wheels and couples this to a bed, while the other transfers individual components to a stand affixed to a bed.https://scholarscompass.vcu.edu/capstone/1139/thumbnail.jp

Radio Number of Hamming Graphs of Diameter 3

For $G$ a simple, connected graph, a vertex labeling $f:V(G)\to \Z_+$ is called a \emph{radio labeling of $G$} if it satisfies |f(u)-f(v)|\geq\diam(G)+1-d(u,v) for all distinct vertices $u,v\in V(G)$. The \emph{radio number of $G$} is the minimal span over all radio labelings of $G$. If a bijective radio labeling onto $\{1,2,\dots,|V(G)|\}$ exists, $G$ is called a \emph{radio graceful} graph. We determine the radio number of all diameter 3 Hamming graphs and show that an infinite subset of them is radio graceful