Negation in English : an essay in game-theoretical semantics : Hand, Michael Robert

Hand, Michael Robert 1985 국내박사

Job satisfaction and intent to leave of nursing assistants in the hospital setting

Hand, Mark C East Carolina University 2015 해외박사(DDOD)

Nursing assistants are an important part of the healthcare team in hospitals. However, there has been little research about the antecedents of job satisfaction and intent to leave of nursing assistants in hospitals. The limited amount of research related to job satisfaction of nursing assistants has been done with nursing assistants in nursing homes. The purpose of this study was to examine the relationship between job satisfaction and intent to leave in hospital based nursing assistant in North Carolina. In addition, the influence of personal characteristics, role related characteristics and job characteristics were examined. The study used a descriptive correlational survey design using the Hospital Nursing Assistant Job Satisfaction Questionnaire. Participants in this study were most satisfied with the work content, coworkers, workplace support, and work schedule. Data revealed a significant relationship between intent to leave, education level and hospital tenure. The strongest predictors for job satisfaction were work schedule, coworkers, chances for more training, and on the job training. The strongest predictors for intent to leave were workplace support, work schedule, and recommend the hospital to a friend. This study represents a beginning understanding of the factors that are associated with job satisfaction and intent to leave of nursing assistants in the hospital setting. Job satisfaction and intent to leave variables have been identified and need further examination to insure that nursing assistants are retained and productive members of the healthcare team.

Theoretical and Computational Tools for Analyzing the Large-Scale Structure of the Universe

Hand, Nicholas A University of California, Berkeley ProQuest Disser 2017 해외박사(DDOD)

The analysis of the large-scale structure (LSS) of the Universe can yield insights into some of the most important questions in contemporary cosmology, and in recent years, has become a data-driven endeavor. With ever-growing data sets, optimal analysis techniques have become essential, not only to extract statistics from data, but also to effectively use computing resources to produce accurate theoretical predictions for those statistics. Future LSS experiments will help answer fundamental questions about our Universe, including the physical nature of dark energy, the mass scale of neutrinos, and the physics of inflation. To do so, improvements must be made to theoretical models as well as the computational tools used to perform such analyses. This thesis examines multiple aspects of LSS data analysis, presenting novel modeling techniques as well as a software toolkit suitable for analyzing data from the next generation of LSS surveys. First, we present nbodykit , an open-source, massively parallel Python toolkit for analyzing LSS data. nbodykit is both an interactive and scalable piece of scientific software, providing parallel implementations of many commonly used algorithms in LSS. Its modular design allows researchers to integrate nbodykit with their own software to build complex applications to solve specific problems in LSS. Next, we derive an optimal means of using fast Fourier transforms to estimate the multipoles of the line-of-sight dependent power spectrum, eliminating redundancy present in previous estimators in the literature. We also discuss potential advantages of our estimator for future data sets. We then present a novel theoretical model for the redshift-space galaxy power spectrum and demonstrate its accuracy in describing the clustering of galaxies down to scales of k = 0.4 hMpc-1 . Finally, we analyze the large-scale clustering of quasars from the extended Baryon Oscillation Spectroscopic Survey to constrain the deviation from Gaussian random field initial conditions in the early Universe, known as primordial non-Gaussianity.

System structure, natural history, dynamic modeling and adaptive management of the Mekong watershed's Tonle Sap-Great Lake, Cambodia

Hand, Richmond Taber University of Maryland, College Park 2003 해외박사(DDOD)

Cambodian food security has been analyzed from a systems perspective in terms of hydrological, ecological, economic, demographic and nutritional processes. Fish in Tonle Sap Lake and its seasonally inundated floodplain---possibly the world's most productive inland fishery (up to 270 kg/ha/yr harvested)---provides up to 70--90% of all animal protein and fat consumed by over 6 million Cambodians all of whom depend on a rice/fish-balanced diet. Two key factors in this biological production are a flood-pulse-and-expansion process originating from the monsoon-swollen Mekong River and the extent of inundated habitat, including the quantity and quality of vegetation. Water development plans and intensive harvest of the lake's fish and floodplain vegetation endanger protein and fat food security in the Lower Mekong River basin. The Tonle Sap Lake's significance for food security is increasing due to a substantial population momentum phase. Food shortages are likely without an overall framework to understand and manage the interdependencies of this complex ecological and socioeconomic system. A field assessment of fish and rice food security in the floodplain was made. A system thinking and group model building course prepared Cambodian faculty for their future role in adaptive management of the fishery stocks. The Tonle Area Management Simulation model (TAMS) was developed to simulate primary ecological economic system dynamics. TAMS represents the interdependent behavior of six sectors: hydraulics; vegetative inundation; gross fish production; macro-economic activity; population dynamics and protein nutrition requirements. As an educational tool, TAMS' user-interface allows creation of scenarios based on conceptual trade-offs among the above sectors. As an initial phase of mediated modeling, TAMS provides a format to promote dialogue and group consensus on system behavior among people with interdependent but competing interests that affect fish production, nutritional and economic welfare. Simulations provide insight relating protein deficit to population growth and a smaller flood pulse to fishery economics. Institutional population projections do not account for protein as a limiting factor; the model clearly demonstrates the mortality effect and the fisheries sensitivity to specific natural and human changes. Awareness of and consensus about such issues fosters wiser, better informed decision-making.

On the physics and chemistry of the ice shell and sub-surface ocean of Europa

Hand, Kevin Peter Stanford University 2007 해외박사(DDOD)

Results from the Galileo spacecraft magnetometer were used to investigate the sub-surface ocean chemistry of Europa and to derive relationships for salinity and ice-layer thickness as a function of induced amplitude response. The best fit to the data is a 4 km ice shell and near saturation salt concentrations. This is the first empirical constraint provided for the ice shell thickness independent of surface geology and thermal models. Results for salt concentration imply that contemporary Europa could be suitable for halophilic organisms, but it may be too salty for the origin of life as we know it. The effect of the jovian magnetic field on the surface of Europa was investigated experimentally. A cryostat-coupled vacuum chamber with an electron gun was used to irradiate thin ice films at temperatures and pressures appropriate to Europa. Hydrogen peroxide production was measured for a range of temperatures, beam currents, and electron energies. Coupled experimental results and numerical models indicate that sub-surface H2O2 concentrations could be significantly larger than the observed surface abundance. Ice mixtures of H2O, CO2, hydrocarbons, and ammonia were irradiated to examine organic chemistry and prebiotic chemistry on Europa. Clathrate hydrates were considered as a mechanism for trapping volatile species. Calculations for oxidant delivery to the sub-surface ocean show that Europa's ocean is not likely to be oxidant limited. Finally, the issue of chemical and molecular biomarkers on the surface of Europa was investigated by irradiating bacterial spores. Implications for future robotic missions are addressed.

The Use of Military Astrology in Late Medieval Italy: The Textual Evidence

Hand, Robert S The Catholic University of America 2014 해외박사(DDOD)

This study examines the thirteenth-century astrologer Guido Bonatti's Liber Astronomicus as a case study to investigate one aspect of the many practical applications of astrology in the later Middle Ages. Specifically, it looks at the application of military astrology to analyze Bonatti's use of his source material in relation to his own practice. The dissertation develops a methodology to discern the astrologer's practice from his textual inheritance. Bonatti was possibly the most important astrologer of the high middle ages. His work was an encyclopedic, yet detailed survey of the entire field of astrological study in the Europe of his day. He acknowledged his Arab sources but was not merely a compiler of their material. Like many of his European contemporaries in other fields such as Thomas Aquinas, Albertus Magnus and Roger Bacon, Bonatti put his own stamp on the field of astrology. Staying within the basic traditions as he inherited them, he systematized and expanded often terse material, and frequently innovated in certain applications of astrology. By close and detailed examinations of Bonatti's text and comparison with his sources, we can see the changes that reflect his personal experience which in turn caused him to alter and emend the tradition. From this we can distinguish the practitioner from the compiler of astrological materials. This study argues that such close internal textual analysis of the astrological treatises themselves reveals the medieval uses of astrology far better than external narrative sources. Ultimately over the course of this study it also becomes clear that in the area of astrology Bonatti carried out the same kinds of intellectual synthesis and systematization that we see in the works of notable contemporaries in other fields.

The regulation of cortical development by Neurogenin2

Hand, Randal A The University of North Carolina at Chapel Hill 2009 해외박사(DDOD)

The mammalian nervous system consists of complex neuronal networks formed by extremely diverse sub-groups of neurons located throughout the body. Neurons of the cerebral cortex form neural circuits with the brain and spinal cord allowing for mammals to sense and interact with their environment. The majority of neurons within the cerebral cortex are classified into two groups: inhibitory GABAergic interneurons and excitatory glutamatergic pyramidal neurons. Pyramidal neurons are the largest population of neurons accounting for approximately eighty percent of all neurons within the cerebral cortex. Pyramidal neurons have several defining features including the use of glutamate as an excitatory neurotransmitter, the mode in which they migrate along radial glia to reach their final location, a unipolar dendritic morphology, and a long projecting axon. Within the cerebral cortex, the basic helix loop helix transcription factor, Neurogenin2 regulates the acquisition of many of the cardinal features of pyramidal neurons. Initially, Neurogenin2 was identified based on its ability to promote neuronal differentiation (proneural function) within the peripheral and central nervous systems. Elegant genetic studies demonstrated that Neurogenin2 also specifies the expression of glutamate as the neurotransmitter for pyramidal neurons. My research identified novel roles for Neurogenin2 including the regulation of radial glia guided migration, their pyramidal dendritic morphology and the axon projection of pyramidal neurons. In addition, I found that a C-terminal tyrosine phosphorylation site in Neurogenin2 was necessary to promote migration and the acquisition of the appropriate dendritic morphology. Loss of function assays revealed that Neurogenin2 regulates the guidance of callosal axons and formation of the corpus callosum. Here, I propose that Neurogenin2 is a master regulator of glutamatergic pyramidal neurons phenotype. Neurogenin2 regulates many aspects required for proper circuit formation including the physical location of neurons, the ability of a neuron to receive afferent signals through proper dendritic morphogenesis, and the ability of a neuron to innervate the proper tissue through the guidance of its long projecting axon. Since Neurogenin2 regulates these aspects of neural circuit formation, it is of no surprise that Neurogenin2 and many of the genes regulated by Neurogenin2 are implicated in mental retardation, epilepsy, and autism spectrum disorders.

Homogenization in cardiac electrophysiology and blow-up in bacterial chemotaxis

Hand, Paul Earl New York University 2009 해외박사(DDOD)

In the first part of this dissertation, we investigate three different issues involving homogenization in cardiac electrophysiology. We present a modification for how heart tissue is typically modeled in order to derive values for intracellular and extracellular conductivities needed for bidomain simulations. In our model, cardiac myocytes are rectangular prisms and gap junctions appear in a distributed manner as flux boundary conditions for Laplace's equation. In other models, gap junctions tend to be explicit geometrical entities. Using directly measurable microproperties such as cellular dimensions and end-to-end and side-to-side gap junction coupling strengths, we inexpensively obtain effective conductivities close to those given by simulations with a detailed cyto-architecture. This model provides a convenient framework for studying the effect on conductivities of aligned vs. brick-like arrangements of cells and the effect of different distributions of gap junctions between the sides and ends of myocytes. We further illustrate this framework by investigating the effect on conductivity of non-uniform distributions of gap junctions within the ends of cells. We show that uniform distributions are local maximizers of conductivity through analytical perturbation arguments. We also derive a homogenized description of an ephaptic communication mechanism along a single strand of cells. We perform numerical simulations of the full model and its homogenization. We observe that the two descriptions agree when gap junctional coupling is at physiologically normal levels. When gap junctional coupling is low, the homogenized description does not capture the behavior that the ephaptic mechanism can speed up action potential propagation. In the second part of this dissertation, we investigate finite-time blow-up and stability of the Keller-Segel model for bacterial chemotaxis. We use a second moment calculation to establish finite-time blow-up for the Keller-Segel system on a disk with Dirichlet boundary conditions and a supercritical mass. We numerically investigate the evolution and stability of the Keller-Segel system in order to provide a conjecture about the generality of boundary blow-up for supercritical mass under the Jager-Luckhaus boundary conditions. Finally, we use the free energy of solutions to Keller-Segel equations to derive a functional inequality that may be helpful for analyzing the stability of steady states.

Inquiry teams: Bridging data informed decision-making and teacher inquiry

Hand, Debbie J University of Pennsylvania 2009 해외박사(DDOD)

In the past eight years, the No Child Left Behind Act of 2001 has led to increased levels of school accountability with a targeted focus on using data as a tool to inform educational decisions and to improve teaching and learning. There is a growing body of research on how data from various assessments can be used to make informed school and classroom-based decisions. The findings presented in the literature illustrate an ongoing struggle between the use of data and its ultimate impact on instructional practices (Wayman, 2005). Specifically, research has highlighted a need to create a culture of collaborative inquiry where teachers have meaningful and purposeful conversations about data that lead to improved teaching and learning (Wayman, 2005; Schmoker, 2004; Copland, 2003). After careful examination of all data available, teachers are expected to test hypotheses and conceptualize a theory of action to help all students learn. Other research suggests that in order to build a community of inquiry, the professional learning of teachers must be grounded in collaboration, reflection and experimentation to affect change in practice (Darling-Hammond & McLaughlin, 1995). In the 2007--2008 school year, the Office of Accountability of the New York City Department of Education mandated the creation and implementation of Inquiry Teams in every NYC public school (K--12). This current study investigates the bridge between data informed decision making and teacher inquiry by implementing a mixed method, cross-case study within the local context of my work environment, which is one of the four Learning Support Organizations (LSOs), affiliated with the New York City DOE. This research was specifically designed to study the impact of the first-year of mandated Inquiry Teams on a purposive sample of schools. The intent was to determine the impact of these teams in developing teachers' abilities in using data to inform instructional practices, supporting a school-wide culture of professional learning and reflective practices, and improving student outcomes for target populations of students. Qualitative analysis will be based on data collected from interviews and observations while quantitative analysis will be performed on teacher survey data and student achievement data.

Cytokines and memory T cell homeostasis

Hand, Timothy Wesley Yale University 2009 해외박사(DDOD)

Memory CD8 T cells can provide long-lived immunity against pathogenic reinfection. As such, knowledge of the factors that contribute to the development, function and maintenance of memory CD8 T cells could be critical in the design of new vaccines. Signals derived from the cytokines IL-2, IL-7 and IL-15 have been shown to be critical for the development of an effective memory CD8 T cell response. In particular, the expression of the receptor for IL-7 (IL-7Ralpha) marks those cells with an increased proclivity to become memory cells from those more likely to initiate apoptosis. To determine whether IL-7Ralpha and IL-7 signals were sufficient for the production of memory CD8 cells we transgenically over-expressed IL-7Ralpha (IL-7Ralphatg) on CD8 T cells. We found that IL-7Ralpha expression was wholly insufficient for memory CD8 T cell production as it neither increased the total number of cells able to survive from the effector phase nor did it allow the survival of more terminally-differentiated effectors at the expense of genuine memory precursors. To investigate the reason for the why IL-7Ralpha did not affect the CD8 response, we treated mice carrying IL-7RalphatgT cells with IL-7 and found that despite equal expression of the receptor, those cells that were more terminally differentiated were unable to respond with increased survival and proliferation. We have since been able to show that only memory precursors are able to maintain the capability to activate the PI3K/AKT pathway in response to IL-2, IL-7 and IL-15. Furthermore we have shown that by inducing constitutive signaling through the PI3K pathway we are able to significantly reduce the death of effector cells following contraction. Finally, memory CD8 T cell function seems to "mature" with time, after the infection has subsided. We tested whether IL-2 and IL-7 induce this "functional maturation". We found that neither IL-7 nor IL-2 induce functional maturation and that IL-2 actually reduces the proliferative potential of developing CD8 memory T cells.