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The employee experience: exploring the relationship between employee experience engagement strategies and employee appraisals of the company
Get PDFThis study explored Morgan’s (2017) employee experience, an engagement strategy with multiple variables in the cultural environment, physical environment, and technological environment. Research was conducted through quantitative content analysis by examining employee experience variables that companies have currently implemented and an analysis of employee sentiments and external communication behaviors towards the organization as a reflection of impacts of the engagement strategies. Internal employee engagement initiatives reflected in the CSR reports and websites of the 2022 top Fortune 100 companies (Forbes, 2022) and the companies’ corresponding Glassdoor reviews were analyzed. Employee engagement is fundamental to organizational success as it promotes motivation, productivity, and efficiency (Maslach & Leiter, 2008; Meskelis, 2017; Kahn, 1990; Kahn, 1992; Gruman & Saks, 2014). However, many companies still lack successful engagement efforts in spite of the empirical research of organizational benefits of having an engaged workforce. The findings of this study indicated that a majority of the companies actively participate in many of the employee experience engagement initiatives as reflected in their CSR reporting and corporate website. However, employee communication behavior revealed that employees are not successfully experiencing a majority of their company’s CSR employee engagement efforts. Therefore, the companies are externally sharing their employee engagement efforts, but the development and implementation of these engagement initiatives are often subpar internally
Locally Finite Tree Actions for Groups of Dimension Two
Get PDFWe investigate finitely generated groups of cohomological dimension 2 and certain actions on locally finite trees. Our setting includes examples of Daniel Wise, which possess two canonical splittings. We show that under suitable hypotheses such a group cannot admit more than two finite-index splittings, up to deformation
Pictographic Motifs: Memory and Mobility on the Upper Missouri
No full textIn “Pictographic Motifs: Memory and Mobility on the Upper Missouri” I investigate a small surviving body of Indigenous painted robes, shirts, and drawings that represent mediated images of intratribal conflict. Indigenous men’s lived experiences shaped their visual expressions, influencing them to grapple visually with the threat of violence that unsettled their communities in the late eighteenth century and early nineteenth century. I analyze the self-portraits of Nueta (Mandan) artists and leaders Mató-Tópe (Four Bears) and Síh-Xídä (Yellow Feather) to understand their martial ambitions: capturing enemies, stealing material goods to count coup, and celebrating victories. While my dissertation focuses on historic Nueta (Mandan) and Nuxbáagas (Hidatsa) territories, my final chapter migrates to Like-a-Fishhook village and the nearby Fort Berthold Indian Reservation. In 1906, Nueta artist Little Owl was commissioned by Orin G. Libby, director of the State Historical Society of North Dakota, to interpret sections of the Missouri River based on his geographic knowledge of the area. His map visually reflects critical links to his ancestral past and challenges settler narratives that continue to reverberate along the shores of the Upper Missouri
Intervalley Scattering in III-V Heterostructures and its Application to Valley Photovoltaic Hot Carrier Solar Cells
Get PDFThe efficiency limit of 33% for a single gap solar cell is not fundamental. Mitigation of thermalization losses which occur when high energy ‘hot’ carriers are only extracted at the same energy as low energy carriers is a viable route towards a solar power conversion efficiency as high as 66%. Previous efforts to develop such a hot carrier solar cell have focused on slowing thermalization through restricting electron-phonon interactions in quantum well structures. This bottleneck effect enables hot phonons to reheat the carrier distribution under high illumination powers. Despite recent success in demonstrating hot carrier effects, maintaining a population of carriers at enhanced energy under more practical conditions (room temperature and weak illumination) remains a challenge.
Here, after observing that hot carrier behavior is affected by scattering to high energy valleys of the conduction band in InAs/AlAsSb multi-quantum well structures, a more robust means of hot carrier maintenance is examined in proof-of-principle InGaAs based heterostructure devices. In these systems, photogenerated hot carriers are preferentially transferred to high energy valleys in the band structure via intervalley phonon scattering rather than thermalizing to the conduction band edge via LO phonon emission. And through inclusion of a doping profile to generate an electric field across the absorber during operation, low energy carriers can also transfer to the high energy upper valleys: the Gunn Effect.
These two mechanisms of intervalley scattering, via intervalley phonons and via the Gunn Effect, result in a simple device structure that demonstrates detectable hot carrier behavior at room temperature and at low incident illumination power. These mechanisms are investigated comprehensively through a series of structures that enable control of the electric field strength (via altered absorber thickness) to better understand how to leverage the benefits of intervalley transfer for hot carrier maintenance, and to the extraction pathway (via altered top n+ layer) to reveal how to overcome the complexities of extracting from an upper valley. While operational photovoltaic devices are yet to be realized, this work provides strong evidence for their practicality and routes toward the realization of such valley photovoltaic hot carrier solar cells
Evaluating the performance of methods for dual-function radar communications
Get PDFDual-Function Radar Communications (DFRC), where a radar and communications function is performed by the same antenna or array, has recently begun to be investigated as a means of alleviating or coping with spectrum congestion. O'Connor and O'Donoughue investigated continuous wave DFRC and this thesis focuses on extending O'Connor and O'Donoughue's treatment to pulsed radar operations.
Timesharing, aperture partitioning, and simultaneous dual-beam (SDB) are compared by spectral efficiency across the amount of power allocated to the communications function, distance, and pulse repetition frequency (PRF). Each DFRC method is also evaluated on its performance on parameter estimators, beamwidth, and detection effects
Detecting upland glaciation in Earth’s pre-Pleistocene record
Get PDFEarth has sustained continental glaciation several times in its past. Because continental glaciers ground to low elevations, sedimentary records of ice contact can be preserved from regions that were below base level, or subject to subsidence. In such regions, glaciated pavements, ice-contact deposits such as glacial till with striated clasts, and glaciolacustrine or glaciomarine strata with dropstones reveal clear signs of former glaciation. But assessing upland (mountain) glaciation poses particular challenges because elevated regions typically erode, and thus have extraordinarily poor preservation potential. Here we propose approaches for detecting the former presence of glaciation in the absence or near-absence of ice-contact indicators; we apply this specifically to the problem of detecting upland glaciation, and consider the implications for Earth’s climate system. Where even piedmont regions are eroded, pro- and periglacial phenomena will constitute the primary record of upland glaciation. Striations on large (pebble and larger) clasts survive only a few km of fluvial transport, but microtextures developed on quartz sand survive longer distances of transport, and record high-stress fractures consistent with glaciation. Proglacial fluvial systems can be difficult to distinguish from non-glacial systems, but a preponderance of facies signaling abundant water and sediment, such as hyperconcentrated flood flows, non-cohesive fine-grained debris flows, and/or large-scale and coarse-grained cross-stratification are consistent with proglacial conditions, especially in combination with evidence for cold temperatures, such as rip-up clasts composed of noncohesive sediment, indicating frozen conditions, and/or evidence for a predominance of physical over chemical weathering. Other indicators of freezing (periglacial) conditions include frozen-ground phenomena such as fossil ice wedges and ice crystals. Voluminous loess deposits and eolian-marine silt/mudstone characterized by silt modes, a significant proportion of primary silicate minerals, and a provenance from non-silt precursors can indicate the operation of glacial grinding, even though such deposits may be far removed from the site(s) of glaciation. Ultimately, in the absence of unambiguous ice-contact indicators, inferences of glaciation must be grounded on an array of observations that together record abundant meltwater, temperatures capable of sustaining glaciation, and glacial weathering (e.g., glacial grinding). If such arguments are viable, they can bolster the accuracy of past climate models, and guide climate modelers in assessing the types of forcings that could enable glaciation at elevation, as well as the extent to which (extensive) upland glaciation might have influenced global climate.Ye
Temperature Swing Solvent Extraction for Selenate and Selenite Removal from Industrial Wastewater
Get PDFCoal-fired power plants provide more than one fifth of the electricity generated in the United States. Flue gas desulfurization (FGD) of the products of coal combustion is necessary to prevent emissions of SO2, which is typically accomplished with wet scrubbing systems. The wastewater from these systems contains high levels of gypsum, chloride, and trace heavy elements including selenium. Effective treatment of FGD wastewater remains a challenge. In this thesis, temperature swing solvent extraction was investigated for its ability to produce freshwater from saline and selenium-containing wastewater. Solute rejection for extractions with diisopropylamine (DPA) was dependent on the ionic strength the feed. DPA showed no selectivity for feeds containing 500 ppm selenate and 500 ppm selenite. NaCl rejection of 81% was achieved for a 3.5 w/w% NaCl feed, and the rejection rose to 93% for the 4.0 NaCl feed. For extractions with synthetic FGD wastewater, DPA rejected 86% of feed selenate and 74% of feed NaCl, indicating DPA can treat dilute contaminants in high TDS feeds. Due to the diminishing solute rejection with more dilute feeds, it was concluded that standalone extraction with DPA is not suitable for FGD wastewater treatment. Extraction with decanoic acid displayed over 98% solute rejection for 3.5 w/w%, 1.0 M, and 4.0 M NaCl feeds. Decanoic acid maintained this rejection for feeds containing 500 ppm selenate and 500 ppm selenite, showing stable rejection of ions independent of feed concentrations. The rejection of each species was slightly lower for synthetic FGD wastewater at 96% for selenate and 95% for NaCl. It was concluded that extraction with DA was feasible as a standalone FGD wastewater treatment. Rejections of selenite were higher than selenate, which were higher than chloride. Selenite has the largest hydrated radius and chloride the smallest, suggesting this property influences ion rejection in multicomponent feeds. Finally, higher DA solute rejection but lower water recovery compared to DPA suggests a tradeoff
Factors Influencing Vaccine-Hesitancy in First-Time Expectant Mothers: A Qualitative Study
No full textObjective. To identify and better understand factors of vaccine-hesitancy in first-time expectant mothers, pertaining to childhood vaccines and compliance with the Advisory Committee of Immunization Practices (ACIP) schedule. Methods. Semi-structured interviews were conducted in the fall of 2018 and spring of 2019 with fifty vaccine-hesitant first-time expectant mothers living in the United States. The Parents Attitude About Childhood Vaccines-modified (PACV-m) survey identified vaccine-hesitancy. The interview question path was developed using the Theory of Planned Behavior and select constructs from the Health Belief Model, feedback from pilot study, and related literature. Interviews were transcribed and analyzed for themes. Conclusion. Most factors of vaccine-hesitancy are driven by a fear of injury to their child. Feeling informed was a factor that built confidence, but there were obstacles to getting reliable and comprehensive vaccine-information. Healthcare providers have an important role by providing vaccine-information during pregnancy, listening without judgment, and engaging in vaccine-related conversations. Most intended to use an alternative or delayed schedule but did not have a definite plan yet. There is parallel between reasons to not accept COVID-19 vaccine and childhood vaccine refusal. Recommendations are made to provide education and training to prenatal healthcare providers and to understand the social norms around the mothers’ decision to vaccinate
Measuring Online Student Engagement in Higher Education: Scale Development, Validation, and Psychometric Properties
Get PDFStudent engagement in online learning environments is of particular importance to successful learning experiences due to the unique features of online learning environments (e.g., physical distance, sense of isolation from peers and instructors). Reliable and valid assessment of student engagement is vitally important for making evidence-based decisions for online learning environments. Addressing this need and the limitations of the existing measures, this study presents a tool to assess student engagement in online learning environments, the Online Engagement in Higher Education (OEHE), which has been validated through a series of confirmatory factor analyses, as well as additional validity analyses, and internal consistency reliability analysis. Using data from 235 undergraduate and graduate students, who took at least one online course during the time of data collection in Fall 2021, a hypothesized three-factor model of online student engagement based on Fredricks et al.’s (2004) engagement framework focusing on three core dimensions of behavioral, emotional, and cognitive engagement was adequately confirmed in the context of CFA. The OEHE was also shown to have reasonable evidence of convergent validity and criterion validity, and strong evidence of discriminant validity through Pearson correlations. The OEHE subscales and the final validated instrument with 20 items also were found to have adequate or very high internal consistency reliability. Implications for the OEHE instrument development and validation and recommendations for future studies are discussed to provide insights for online engagement researchers, practitioners, and other stakeholders in online education
Label-Free, Live Cell Nanoparticle Imaging for Real-Time Uptake Pathway Analysis
Get PDFNanoparticles are biomedical devices capable of a wide range of applications ranging from drug delivery to molecular sensing and bioimaging agents. Within bioimaging, nanoparticles face numerous obstacles in both in vitro and in vivo applications. Upconversion nanoparticles, capable of absorbing photons and emitting photons at a shorter wavelength, provide a promising modality for addressing many of these in vitro and in vivo obstacles, including low background, comprehensive surface coating options, and applications in multimodal imaging. When considering specific applications however, such as monitoring of nanoparticle endocytosis, simpler, more environmentally friendly, and more cost-effective techniques could improve the rate at which research is conducted by reducing the overhead cost and laboratory expertise required to run such an experiment. To those aims, this thesis serves two primary purposes: first to introduce, evaluate, and direct the current research aimed at developing upconversion nanoparticles as a widely used bioimaging modality, and then to develop a simple technique capable of monitoring living cell nanoparticle uptake rates in a model macrophage system