Utility of the Causal Inference Approach to Mediation Analysis With Binary Outcomes

This dissertation is methodological research to inform educational researchers that the causal inference approach will produce a more accurate estimate of a mediation effect. The effect will help researchers make important and accurate decisions such as changing teaching curricula or implementing interventions

STRUCTURE, ELECTRICAL PROPERTIES, AND APPLICATION POSIBILITY AS SOLID OXIDE FUEL CELLS CATHODE MATERIALS OF (La2NiO4±δ)1-x(BaTiO3)x(x=0.0-0.5) COMPOSITES

(La2NiO4±δ)1-x(BaTiO3)x (LNO/BTO), x=0.0, 0.05, 0.2, 0.3, 0.5 composites were prepared and investigated in structure and electrical properties. Single phase La2NiO4±δ component was obtained by sintering at 1000 oC during 12 h in air. Electrical conductivity was measured by 4-point probe method in wide temperature region above room temperature. Experiment showed that the highest conductivity was obtained in x=0.3 composite sample. Glass shell-nanocrystallite core structure of grains plays important role for this conducting enhancement. Conducting behavior of composites change from metal to semiconductor in the temperature interval of 400 to 700 oC. The LNO/BTO systems with acceptable electrical conductivity in such temperature interval are suitable for making cathode materials in solid oxide fuel cells

The Role of Type A Behavior Pattern on the Stressor-Strain Relationship in Nurses

Three models (direct effects, moderated effects, and mediated effects) were used to test the role of Type A Behavior Pattern (TABP) in the stressor-strain relationship. The longitudinal study measured stressors (role ambiguity, role overload, and role conflict), strains (anxiety, tedium, affective commitment, intent to leave, and general well-being), and TABP in hospital nurses across two survey administrations. Stressors at Time 1 and strains at Time 2 were utilized for the analyses. TABP was found to have direct effects on anxiety and general well-being. In addition, TABP partially moderated the relationship between role conflict and anxiety and tedium, as well as the relationship between role overload and anxiety, tedium, and general well-being. No support was found for the mediator relationship. These findings suggest that Type A nurses experience greater anxiety, tedium, and lower general well-being in response to high role conflict and role overload than Type B nurses

Muon Transfer from Muonic Hydrogen to Atomic Oxygen and Nitrogen

The results of diabatic hyperspherical close-coupling calculations are presented for the charge exchange of a negative muon from muonic hydrogen to oxygen and nitrogen for collision energies from 10-3 to 103 eV. It is shown that converged results can be obtained using a much smaller number of channels than in the traditional adiabatic approach. For the energy range below 10 eV our results for nitrogen are in good agreements with the available experimental data and the recent calculations within hyperspherical elliptic coordinates. However, discrepancies were found in the case of oxygen, where a p -wave shape resonance is shown to contribute significantly to the cross sections. We show that for oxygen the p -wave resonance extends to a large volume and is sensitive to the many-body effect. Calculations including outer screening of the oxygen atom have been performed to illustrate the importance of this effect

Factorization of high-harmonic generation yields in impurity-doped materials

We present a theoretical investigation of high-harmonic generation (HHG) from impurity-doped materials using the time-dependent Schr\"odinger equation (TDSE) approach. We demonstrate the factorization of HHG yields as a product of an electron wave packet and the recombination cross section, in analogy to HHG from atoms and molecules in the gas phase. Furthermore, we show that the quantitative rescattering model based on this factorization accurately reproduces the TDSE results. This opens up new possibilities to study impurities in materials using the available techniques from strong-field physics

Polarization and ellipticity of high-order harmonics from aligned molecules generated by linearly polarized intense laser pulses

We present theoretical calculations for polarization and ellipticity of high-order harmonics from aligned N$_2$, CO$_2$, and O$_2$ molecules generated by linearly polarized lasers. Within the rescattering model, the two polarization amplitudes of the harmonics are determined by the photo-recombination amplitudes for photons emitted parallel and perpendicular to the direction of the {\em same} returning electron wave packet. Our results show clear species-dependent polarization states, in excellent agreement with experiments. We further note that the measured polarization ellipse of the harmonic furnishes the needed parameters for a "complete" experiment in molecules.Comment: 4 pages, 4 figure

Quality Expectations of Social Networking Sites: A Comparative Study Between New Zealand and Vietnam

Online Social Networking (OSN) websites have been growing fast and their success is decided by customers’ satisfaction. User satisfaction can be measured using a number of popular frameworks such as SERVQUAL, SERVPERF, SiteQual, and WebQual. These frameworks are often used as guidelines when designing, implementing, and assessing quality of websites in general and can also be used to measure the quality of online social networking websites. Besides, there are additional factors that should be taken into consideration when assessing user satisfaction such as demographic differences and cultural differences. The present research project aims to investigate and test the linkage between culture and user satisfaction on the online social networking websites. This is achieved by conducting an analysis on the basis of a survey in two different countries – New Zealand and Vietnam. The research project’s principal component analysis follows Hofstede’s six cultural dimensions and the modified framework of assessing online social networking sites quality conducted by Rizavi, Ali, and Rizavi in 2011. The results suggest that users’ quality expectation of Social Networking Sites (SNS) in New Zealand and in Vietnam may be influenced by cultural differences