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THE IMPACT OF SERVANT LEADERSHIP ON SOCIAL LOAFING IN THE WORKPLACE: EXAMINING MECHANISMS AND BOUNDARY CONDITIONS.
No full textThis dissertation explores the complex relationship between servant leadership and social loafing within organizational settings. Drawing upon the collective effort model, social exchange theory, and trait activation theory, this research explores how servant leadership impacts social loafing. Employing a two-wave online survey methodology with full-time workers in the USA, this study examines the direct effects of servant leadership on social loafing and investigates the mediating roles of perceived insider status, civility, and psychological empowerment. Furthermore, it assesses how individual differences—such as honesty-humility, psychological entitlement, and exchange ideology—moderate these relationships.Initial findings reveal a complex relationship between servant leadership and social loafing, with certain components of servant leadership directly influencing social loafing in both positive and negative directions. Specifically, emotional healing and ethical behavior factors of servant leadership were found to reduce social loafing, whereas putting subordinates first appears to unexpectedly increase social loafing. In addition, with the inclusion of social desirability, task interdependence, and task visibility as control variables, we see a marked decrease in the direct relationship between servant leadership and social loafing. Importantly, servant leadership does act as an indirect negative influence on social loafing through the mediating mechanisms of psychological empowerment, perceived insider status, and perceived leader civility. However, there were no detectable moderation effects from our interaction variables of psychological entitlement, honesty/humility, and exchange ideology. The research contributes to the broader literature on leadership and motivation by highlighting the conditional effects of servant leadership on individual motivation within groups, offering valuable insights for organizational leaders aiming to foster a culture of high engagement and minimal social loafing. Through a comprehensive analysis, this dissertation provides a deeper understanding of how servant leadership can be effectively leveraged to combat social loafing, emphasizing the importance of aligning leadership approaches with individual employee characteristics and group dynamics
DEEP LEARNING-BASED IMAGE RECONSTRUCTION FROM MULTIMODE FIBER: COMPARATIVE EVALUATION OF VARIOUS APPROACHES
No full textThis thesis presents three distinct methodologies aimed at exploring pivotal aspects within the domain of fiber optics and piezoelectric materials. The first approach offers a comprehensive exploration of three pivotal aspects within the realm of fiber optics and piezoelectric materials. The study delves into the influence of voltage variation on piezoelectric displacement, examines the effects of bending multimode fiber (MMF) on data transmission, and scrutinizes the performance of an Autoencoder in MMF image reconstruction with and without additional noise. To assess the impact of voltage variation on piezoelectric displacement, experiments were conducted by applying varying voltages to a piezoelectric material, meticulously measuring its radial displacement. The results revealed a notable increase in displacement with higher voltage, presenting implications for fiber stability and overall performance. Additionally, the investigation into the effects of bending MMF on data transmission highlighted that the bending process causes the fiber to become leaky and radiate power radially, potentially affecting data transmission. This crucial insight emphasizes the necessity for further research to optimize data transmission in practical fiber systems. Furthermore, the performance of an Autoencoder model was evaluated using a dataset of MMF images, in diverse scenarios. The Autoencoder exhibited impressive accuracy in reconstructing MMF images with high fidelity. The results underscore the significance of ongoing research in these domains, propelling advancements in fiber optic technology.The second approach of this thesis entails a comparative investigation involving three distinct neural network models to assess their efficacy in improving image quality within optical transmissions through multimode fibers, with a specific focus on mitigating speckle patterns. Our proposed methodology integrates multimode fibers with a piezoelectric source, deliberately introducing noise into transmitted images to evaluate their performance using an autoencoder neural network. The autoencoder, trained on a dataset augmented with noise and speckle patterns, adeptly eliminates noise and reconstructs images with enhanced fidelity. Comparative analyses conducted with alternative neural network architectures, namely a single hidden layer (SHL) model and a U-Net architecture, reveal that while U-Net demonstrates superior performance in terms of image reconstruction fidelity, the autoencoder exhibits notable advantages in training efficiency. Notably, the autoencoder achieves saturation SSIM in 450 epochs and 24 minutes, surpassing the training durations of both U-Net (210 epochs, 1 hour) and SHL (160 epochs, 3 hours and 25 minutes) models. Impressively, the autoencoder\u27s training time per epoch is six times faster than U-Net and fourteen times faster than SHL. The experimental setup involves the application of varying voltages via a piezoelectric source to induce noise, facilitating adaptation to real-world conditions. Furthermore, the study not only demonstrates the efficacy of the proposed methodology but also conducts comparative analyses with prior works, revealing significant improvements. Compared to Li et al.\u27s study, our methodology, particularly when utilizing the pre-trained autoencoder, demonstrates an average improvement of 15% for SSIM and 9% for PSNR in the worst-case scenario. Additionally, when compared to Lai et al.\u27s study employing a generative adversarial network for image reconstruction, our methodology achieves slightly superior SSIM outcomes in certain scenarios, reaching 96%. The versatility of the proposed method is underscored by its consistent performance across varying voltage scenarios, showcasing its potential applications in medical procedures and industrial inspections. This research not only presents a comprehensive and innovative approach to addressing challenges in optical image reconstruction but also signifies significant advancements compared to prior works. The final approach of this study entails employing Hermit Gaussian Functions with varying orders as activation functions within a U-Net model architecture, aiming to evaluate its effectiveness in image reconstruction. The performance of the model is rigorously assessed across five distinct voltage scenarios, and a supplementary evaluation is conducted with digit 5 excluded from the training set to gauge its generalization capability. The outcomes offer promising insights into the efficacy of the proposed methodologies, showcasing significant advancements in optical image reconstruction. Particularly noteworthy is the robust accuracy demonstrated by the higher orders of the Hermit Gaussian Function in reconstructing MMF images, even amidst the presence of noise introduced by the voltage source. However, a decline in accuracy is noted in the presence of voltage-induced noise, underscoring the imperative need for further research to bolster the model\u27s resilience in real-world scenarios, especially in comparison to the utilization of the Rectified Linear Unit (ReLU) function
THE EVOLUTION OF HYLOBATID POSITIONAL BEHAVIOR AND POSTCRANIAL OSTEOLOGY
No full textA comparative understanding of the patterns and processes of hominoid evolution is critical for determining the evolutionary trajectories of our own species. Several traits, including the development of relatively large-body size, a torso-orthograde (or upright; TO) -Bauplan, and suspensory adaptations are often considered key adaptations within the Hominoidea. Unfortunately, comparisons of the neontological and paleontological records have resulted in divergent theories regarding the origin of these traits, with one extreme advocating their homologous origins and the other for rampant homoplasy. It is argued here that a key factor that has continued to limit our understanding of hominoid and human evolution is the underutilization of hylobatids within comparative studies. The Hylobatidae are an extremely successful radiation of moderate-sized primates from the superfamily Hominoidea. The extant hylobatid family currently comprises four genera and 20 species spanning 11 countries in East, South, and Southeast Asia, with three known extinct genera from China and potentially one from India. Hylobatids are the smallest of the extant apes yet size-variable and are among the most orthograde/suspensory. Nevertheless, their natural variation is often condensed into a single observation point in comparative studies. As such, the goal of this dissertation is to document the variation in positional behavior and postcranial osteology among hylobatids, utilizing an ecological morphological framework, and to integrate this detailed evaluation with previous neontological and paleontological studies. Several interrelated studies are presented within this dissertation, including a new comparative look at hylobatid postcranial osteology and several new studies of hylobatid positional behavior from the wild. These investigations shed light on the adaptive niche of hylobatids and provide insights into the evolutionary processes that shaped this uniquely successful hominoid family. Moreover, the new results presented here allow for a more critical understanding of hominoid evolution and facilitate the synchronization of the neontological and paleontological records. In doing so, this study provides support to the theory that hylobatids and hominids have developed their body size regimes, TO-Bauplan, suspensory morphological adaptions, and accompanying TO-positional behavioral repertoire independently
GETTING TO THE ROOT OF WHETHER TOOTH EXTRACTION INFLUENCES NEUROANATOMY AND BEHAVIOR: A STUDY OF NAKED MOLE-RAT BEHAVIOR AND THE AFFECTIVE ASPECTS OF DENTITION
No full textHaving an appropriate understanding of the behavioral and physiological impact of a disease requires thoroughly fielded tests and wide-ranging animal models to properly deduce generalized impacts of the disease under investigation. Through novel animal models, we acquire diverse insights into the mechanisms at play so that we may approach the problem at hand with fresh perspective and renewed vigor. Using the naked mole-rat (Heterocephalus glaber), a species becoming increasingly common in the medical sciences, my dissertation aimed to accomplish the aforementioned goals in two parts: 1) take the naked mole-rat through a battery of behavioral tasks to bolster our capabilities of using this animal model in medical research; and 2) introduce the naked mole-rat as an alternative model for the investigation of how loss of dental sensation alters behavior and neuroanatomy. Chapter two describes the many methods with which I tested the naked mole-rat across a variety of typical behavioral tasks for social dominance, learning and memory, anxiety, depression, and sociability. Included herein were tests to determine appropriate motivators for this subterranean species to perform such tasks. Additionally, due to the naked mole-rat’s unique disposition for biting, I measured their biting behaviors and compared them across rodent and other mammalian species. The results show that naked mole-rats exhibit large evolutionary divergence in their sensory capabilities and great consideration needs to be given to the proper behavioral tasks and subsequent evaluations of these behavioral paradigms. In chapter three, I evaluated the impact of tooth extraction on affective behaviors, learning and memory, and sociability. Chapter four sought to uncover underlying neuroplasticity associated with the behavioral tasks performed in chapter three. Additionally, in chapter four, I investigated plasticity of the traditional somatosensory pathway for tooth sensation. Tooth loss decreased neuronal density of contralateral ventral posteromedial nucleus of the thalamus and increased the neuronal density of the contralateral ventral dentate gyrus, indicating that tooth-loss induced neuronal plasticity may be more related to plasticity of pain circuitry or resultant from alterations in the muscles of mastication following tooth loss. Though no significant changes in the hippocampus arose from one year of living with no right incisor, I theorized as to which of the physiological idiosyncrasies exhibited by Heterocephalus glaber may have inhibited any observable plasticity due to tooth loss
STUDY OF RESILIENT MODULUS AND GEOTECHNICAL PROPERTIES OF POLYMER STABILIZED HIGH PLASTICITY CLAY
No full textSoil stabilization is a widely used technique in the field of geotechnical engineering for a wide range of applications. Traditional stabilizers such as cement and lime, although very efficient, are not environmentally friendly as they leave major carbon footprints, therefore the demand for sustainable stabilization methods is escalating. This research investigates the potential of two different polymers e.g., a biopolymer derived from organic source, and an inorganic commercially manufactured polymer, as viable alternatives for soil stabilization. The current study focuses on exploring the efficacy of polymers stabilized soil in improving the engineering or geotechnical properties such as plasticity, compressibility, shear strength, and stiffness behavior.The research methodology involves using locally available high plastic clay for stabilization using two different types of polymers and performing laboratory experiments to analyze the strength parameters of the stabilized soil. Xanthan Gum (XG) is a biopolymer which is being studied is used in the percentages of 0.5%, 1.0% and 1.5% by dry weight of soil mass to understand the mechanism of biopolymer-soil interactions and to conclude optimum percentage suitable for stabilization in terms of technical and economical value. Similarly, Soiltac (ST) a vinyl copolymer inorganic polymer is used in 1.5% of dry mass of soil (optimum dosage as per previous literature) to compare its effectiveness with that of Xanthan Gum. After the determination of Atterberg limits and Optimum Moisture Content (OMC) and Maximum Dry Density (MDD), the samples were subjected to tests such as Unconfined Compressive Strength (UCS), Ultrasonic Pulse Velocity (UPV), Resilient Modulus (RM) test and Consolidation test. The prepared UCS samples were cured for 0, 7, 14, and 28 days in open air condition before performing test on them. Atterberg limits test on untreated Carbondale Soil were conducted to classify the soil as CH (Clay with high compressibility) type as per USCS (Unified Soil Classification System) classification. While tests on treated sample showed significant increasement in Liquid Limit (LL), slight increment in Plastic Limit (PL), thus quite surge in the Plasticity Index (PI) with increase in XG percentage in the soil. UCS value increased with the increase in percentage addition of XG. Also, UCS results from both untreated and polymer treated samples showed increase in compressive strength with increase in curing period. UCS value increased from 417.75 psi to 490.24 psi, 504.05 psi, and 542.91 psi for 0.5%, 1.0%, and 1.5% XG addition, respectively. This increase in UCS value was 17.35%, 20.66%, and 29.96% for the corresponding XG concentrations. The treated samples had a significant increase in the UCS for all the curing period in comparison to their respectively cured untreated sample. The percentages increase in the UCS for 1.5% XG sample in comparison to untreated sample cured for the same period is 6.45%, 59.57%, and 29.96%, respectively for 7, 14 and 28 days of curing. However, for the zero-day test, the UCS of 1.5% XG stabilized sample was found to be less than the zero-day untreated sample. With the addition of ST polymer, the UCS value increased for all the curing period while comparing with the UCS of untreated soil for the same curing period. The UCS of the ST treated soil increased from 58.56 psi to 467.367 psi when cured for 0 and 28 days which is an increase of 698.1 % i.e. 7 times the strength at 0 day. When UPV (Ultrasound Pulse Velocity) tests were compared with the UCS value for the same sample, the result showed that the higher UPV value corresponded to the higher UCS value. This relationship was supported by the high degree of correlation between the two measurements. The consolidation test showed that the Compression Index (Cc) of XG stabilized soil decreased as the percentage of XG added increased. Cc decreased from 0.2795 for pure Carbondale Soil (CS) to 0.2003 for 1.5% XG addition which is a drop of 28.33%. Likewise, Cc decreased by 3.0% and 19.33% for 0.5% and 1.0% XG doses respectively. The primary aim of this study is to simplify the understanding of the Resilient Modulus (RM) test, which yields vital data for pavement design. The efficacy of inclusion of stabilizer was further substantiated by RM testing which confirmed the enhancement of soil resilient qualities compared to the untreated soil. The RM values exhibited a growing trend, indicating an enhancement in the soil\u27s stiffness and capacity to endure repetitive loads. This attribute is extremely important for applications such as the construction of pavements and foundations that are subjected to dynamic loads. The samples containing 1.0% XG showed significant increases in their RM values. Specifically, the RM values increased by 18.5%, 40%, and 39.5% after being cured for 7, 14, and 28 days, respectively, at a confining pressure of 6 psi. Similarly, the RM for the case of ST ranges from 15227.60 psi for 0 days of curing and 2 psi of confining stress to 45375 psi for 28 days of curing and 6 psi of confining pressure. The performance of ST against XG is higher
A JOURNEY TO THE CENTER OF THE ASTHENOSPHERE: A NUMERICAL EXPLORATION OF MAGMA PRODUCTION BENEATH MID OCEAN RIDGE AND SUBDUCTION ZONE SYSTEMS
No full text2-D numerical computer models based on thermodynamic and kinematic principles have become invaluable tools for simulating geodynamic processes at these systems. Numerical models have proven effective for allowing the examination and computation of multiple factors simultaneously, providing scientists with an important resource with which to study complex systems. Previously, for instance, numerical models have been used for examining different factors involved in magma production at subduction zones and mid ocean ridges by modelling the influence and interplay of factors such as the effect of hydration and the influence of the depth of the fault between the two plates on the melting (van Keken, 2003; van Keken 2008). Additional models have explored the thermal structure of subduction zones and its relationship to the processes involved at convergent boundaries, including magma production (van Keken, 2023a). Syracuse et al. (2010) used numerical models for subduction zones, creating thermal models that examined dehydration and melting in subduction zones with a variety of slab geometries, convergence velocities, ages and structures. Still others have shown that thermal structure affects melt production, formation of arc volcanoes, dehydration, and seismicity, modelling the effects of varying slab dip, plate convergence velocity, plate age, etc. (Syracuse et al., 2010; Hayes et al, 2018). However, none have yet utilized models to systematically investigate magma production at either subduction zones or mid-ocean ridges to specifically examine both batch and fractional melting with the combination of multiple controlling factors including slab dip, convergence rate, hydration, minerology, and slab age. This project investigated the processes surrounding magma production at subduction and mid-ocean ridge systems through the creation of a numerical model and utilization of the developed model to explore the effects of a multitude of parameters on fractional and batch melting, as well as investigated the incorporation of incompatible elements, and other processes of interest in subduction and mid ocean ridge systems
EXPLORING PERSPECTIVES, PRACTICES, AND PROFESSIONAL DEVELOPMENT: COLLEGIATE LEVEL ESL/EFL TEACHERS’ UTILIZATION OF TECHNOLOGY IN LANGUAGE EDUCATION
No full textA breadth of research has revealed that English as a Second Language (ESL) and English as a Foreign Language (EFL) teachers are positive towards technology integration in their classrooms (Sun & Mei, 2022) and are willing to develop their knowledge on ways to utilize technology (Nguyen, 2022). Nonetheless, there is limited information in terms of the impact of teachers’ past experiences and learning opportunities on how they implement technology in their teaching practices. Therefore, this research aims to expand on teachers’ perspectives, uses of technology, and their professional development with regard to technology. The research questions that guide this study are: 1) What are the perspectives of ESL/EFL teachers on technology integration in ESL/EFL classrooms? 2) How do ESL/EFL teachers utilize technology? 3) What factors influence ESL/EFL teachers’ past and ongoing development in technology enhanced language teaching? To address these research questions, this mixed-methods study employed online survey and interviews as the data collection instruments. Also, this research utilized thematic analysis to analyze the data from ten collegiate level ESL/EFL teachers. The participants of this study teach in two different countries: Turkey and the United States (U.S.), which increased the context-specific diversity of the data. Findings of this paper suggest that teachers have positive perspectives on technology integration in their classes and their practices of technology implementation vary depending on their teaching context and experiences. The findings also reveal that hands-on experiences and teacher collaboration have positive effects on teacher professional development with respect to technology. Along with the positive perspectives and various uses of technology, this study touches on drawbacks of technology such as student distraction, cheating/plagiarism, and other logistical difficulties. The research concludes with implications and recommendations for future research
SEEING WITH NEW EYES: A COSTUME DESIGN THESIS ON WEDDING BAND: A LOVE/HATE STORY IN BLACK AND WHITE
Get PDFAN ABSTRACT OF THE THESIS OFJennifer N. Helms, for the Master of Fine Arts degree in Theater Design, presented on March 26, 2024, at Southern Illinois University Carbondale. TITLE: SEEING WITH NEW EYES: A COSTUME DESIGN THESIS ON WEDDING BAND: A LOVE/HATE STORY IN BLACK AND WHITEMAJOR PROFESSOR: Wendi R. Zea This thesis document is a presentation and exploration of the process involving the costume design for Wedding Band: A Love/Hate Story in Black and White by Alice Childress. The play was produced in the Christian H. Moe Laboratory Theatre at Southern Illinois University Carbondale and ran from November 30 – December 10, 2023. This dramatic play explores the complexities of racism, prejudice, alienation, love in all forms, and the value of female kinship. It reminds us that fear brings out the very real ugliness of hate; while leading with love gives us strength to stand up with dignity, courage to face the ugly, and motivation to push through the bitterness of heartache to take care of the ones we love. Chapter 1 contains the research, background information, and script analysis that was conducted to prepare and inform the design of the costumes. This chapter also highlights the goals I wanted to achieve within my design and on a personal level. Chapter 2 focuses on the design process and how the costume design evolved through collaboration, continued research, and discussion. Chapter 3 documents the production process of the design and how it progressed to realization, including an examination of the dress rehearsals and the production’s performances. Chapter 4 records an analysis of the entire design and its evolution through outside critiques, commentary, and self-reflection
Through the Lens
No full textThrough The Lens is a multimedia installation and performance that deals with how Black are viewed in society from the perspective of a Black graphic artist. As a Black man myself, it comes from only my perspective, however, it can be used as a gateway for larger conversations to occur for change for the better. Through the Lens is an experience. An experience, in which Black Men are allowed to speak their peace, while allowing those around to hear and see them for who they are versus what society has conditioned us to think. It consists of several different photographic, video installations, and community/live-based accounts of how society portrays Black as negative, through the use of storytelling and real-life accounts. Through the Lens aims to take the negative and turn it into a positive, and using community involvement to do so. The intent is to engage in a useful and intelligible conversation about how to change that language that we have come so fond of knowing and to live cohesively together, while changing the narrative that has held Blacks, especially Black Men, to for so long
UNDERSTANDING THE P53-MDM2 BINDING/UNBINDING MECHANISM AND POTENTIAL MUTATION HOTSPOTS IDENTIFICATION THROUGH IN-SILICO STUDIES
No full textThe interaction between the tumor suppression protein p53 and ubiquitin ligase MDM2 that negatively regulates p53, plays a crucial role in controlling cell growth in cancerous tissues. MDM2 binds p53 through the N-terminal transactivation domain of p53, inhibiting its transcription activity and promoting its degradation. This negative feedback loop maintains low p53 levels in normal cells. Disrupting the p53-MDM2 interaction in cancer cells is a promising approach for therapy. To explore the probable binding/unbinding pathway of p53 during the formation/dissociation of the p53-MDM2 complex, we performed a Molecular Dynamics (MD) investigation of the p53-MDM2 complex (PDB ID :1YCR). We investigated the potential of mean force (PMF) to understand the free energy landscape of the dissociation process. Additionally, we examined p53\u27s stability and structural dynamics as its distance from MDM2 is varied. Furthermore, we mutated the protein p53 and obtained p53 based peptides that mimic p53. We also identified 10 inhibitors computationally and they were docked with MDM2. By using computational analysis, we studied structural stability of these p53 mimics and other inhibitors and carried out MD simulations combined with Umbrella Sampling simulations to study the dissociation energy of the complexes