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The Influence of Psychological Safety on Leadership Attitudes and Beliefs in College Students
No full textThe goal of the present study is to examine whether there is a link between experiences of psychological safety and certain beliefs and attitudes college students have about organizational leadership. While the locus of most of the research on psychological safety is the workplace, this study examines the effects of psychological safety in three environments: home, school, and work. One-hundred and ninety-nine psychology students reported their experiences and attitudes by completing an online survey. The results showed no significant relationship between psychological safety and systemic and hierarchical beliefs about leadership. The findings, as well as recommendations for future research, are discussed
The Role of Actin Associated SPTBN1 Host Factor in HIV-1 Infection in Microglial Cells
No full textHuman immunodeficiency virus (HIV) is a chronic illness affecting more than 32.7 million individuals worldwide. The virus infects immune cells, weakening the immune system overtime eventually leading to acquired immunodeficiency syndrome (AIDS) if left untreated. Infection starts with a fusion step, followed by uncoating of the HIV capsid once in the cytoplasm of the cell. HIV uses host cell proteins to complete the infection process, like the actin associated factor, SPTBN1. The Hulme lab has previously shown that SPTBN1 knockdown by siRNA in microglial cells decreased HIV infection and delayed uncoating of HIV. Because fusion is prior to uncoating, it is important to verify that fusion delay was not the reason uncoating was delayed. The goal of this thesis research was to further determine the role of SPTBN1 in HIV infection of microglial cells that are a natural host for HIV. The siRNA knockdown of SPTBN1 was optimized, achieving knockdown between 67-94%. A knockdown of SPTBN1 was done to confirm that it decreases infection, and the fusion kinetics were observed by a fusion assay. The fusion step of HIV infection was determined to not be affected by SPTBN1 knockdown with fusion kinetics being similar to control conditions. These results support the labs previous conclusion that SPTBN1 is involved in the uncoating step of HIV infection that follows fusion. Researching hosts factors such as SPTBN1 provide important insights to how HIV infects cells and identifies areas of interest that can be targeted by medications
Emotion Validating Language Regarding Negative Emotions in the Classroom Differing by Gender and Emotion Type
No full textThis study examined teachers’ emotion validating language regarding negative emotion in early childhood classrooms. By analyzing teachers’ emotion language differing by gender, the research highlights the gendered socialization of emotional expression, especially regarding negative emotions, in early childhood contexts. In toddler and preschool classrooms, 28 teachers were video recorded during 4 thirty-minute sessions of free play time. Videos were coded for teachers’ emotion language regarding negative emotions with attention to the gender of the child to whom the language was spoken. Results indicate that teachers validate negative emotions more to girls than to boys. This aligns with previous research that suggests that girls’ expression of emotion is more encouraged and acceptable than boys. Additionally, exploratory analyses of the type of emotion discussed suggest that teachers validate sadness less to boys than to girls and validate anger more to boys than to girls. This work highlights potential gender differences in emotion socialization and points to missed opportunities to validate boys’ negative emotions and thus develop their emotion language and regulation skills. Implications for teacher professional development are discussed
On the Synthesis and Characterization of Bimagnetic CoO/NiFe2O4 Heterostructured Nanoparticles
No full textBimagnetic nanoparticles show promise for applications in energy efficient magnetic storage media and magnetic device applications. The magnetic properties, including the exchange bias of nanostructured materials can be tuned by variation of the size, composition, and morphology of the core vs overlayer of the nanoparticles (NPs). The purpose of this study is to investigate the optimal synthesis routes, structure and magnetic properties of novel CoO/NiFe2O4 heterostructured nanocrystals (HNCs). In this work, I aim to examine how the size impacts the exchange bias, coercivity and other magnetic properties of the CoO/NiFe2O4 HNCs. The nanoparticles with sizes ranging from 10 nm to 24 nm were formed by synthesis of an antiferromagnetic (AFM) CoO core and deposition of a ferrimagnetic (FiM) NiFe2O4 overlayer. A highly crystalline magnetic phase is more likely to occur when the morphology of the core-overgrowth is present, which enhances the coupling at the AFM-FiM interface. The CoO core NPs are prepared using thermal decomposition of Co(OH)2 at 600 °C for 2 hours in a pure argon atmosphere, whereas the HNCs are obtained first using thermal evaporation followed by hydrothermal synthesis. The structural and morphological characterization made using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques verifies that the HNCs are comprised of a CoO core and a NiFe2O4 overgrowth phase. Rietveld refinement of the XRD data shows that the CoO core has the rocksalt (Fd3̅m) crystal structure and the NiFe2O4 overgrowth has the spinel (C12/m1) crystal structure. SEM-EDS data indicates the presence and uniform distribution of Co, Ni and Fe in the HNCs. The results from PPMS magnetization measurements and high-resolution transmission electron microscopy (HR-TEM) of the CoO/NiFe2O4 HNCs are discussed herein
Equine-Assisted Therapy and Learning Interventions With Youth: A Meta-Analysis and Quasi-Experimental Study.
No full textEquine-assisted psychotherapy interventions have become increasingly used and tested as an alternative or complementary approach with youth. This project presents two studies. The first study consists of an overview of existing reviews and a meta-analysis of controlled and comparison studies on the effectiveness of equine interventions with youth. A comprehensive search and selection procedure produced 3,525 records, from which 56 quantitative studies were identified, and ultimately 16 controlled or comparison studies were selected for inclusion in the meta-analysis. Results showed a statistically significant, medium, and homogenous effect size for the overall effectiveness of equine interventions for youth psycho-social outcomes (n = 16, d = .535, 95% CI [.345, .726], p \u3c .001, I2 = 0.39). Included studies showed several limitations in design, as determined by the Joanna Briggs Institute (JBI) Checklist for Quasi-Experimental Studies, most frequently concerning the lack of complete, analyzable follow-ups, inappropriate or inadequate statistical analyses or reporting, and a lack of a clear control and experimental group. The second study is a pre-post quasi-experiment, which first, examined the reliability and validity of the Horses Assisting Youth Parent (HAY-P) and Staff (HAY-S) scales. Study 2 also examined differences in psycho-social outcomes after the implementation of equine-assisted learning interventions with youth referred for emotional and behavioral problems and if there were differences in the changes between genders. This study consisted of 560 participants (ages five to 17), who were deemed “at-risk” and presented with social/emotional challenges. De-identified data was analyzed for this study. Prior to the main analyses, the HAY-P and the HAY-S scales were examined for its reliability and validity of scores. Results showed statistically significant (p \u3c .001) improvements for youth on the HAY-P and HAY-S Total, Contentment and Communication, as well as Compliance and Focus scores with large to very large effect sizes (d = 1.081 to 2.717) across all six outcome measures. Though the meta-analysis found equine-assisted therapies/activities to be an effective intervention for youth with psycho-social challenges compared with comparison treatments and the quasi-experiment showed significant improvements from pre to post treatment, more research is needed utilizing larger samples, randomized control designs, and concerning specific outcomes and groups
Optimizing the Fluorescent Quantum Yield of Carbon Dots
No full textCarbon dots (CDs) are a subclass of carbon nanomaterials that exhibit unique properties of fluorescence, photostability, low toxicity, and biocompatibility. These unique properties have enabled numerous applications including biosensing, heavy-metal detection, and pH-sensing, among others. Their optical properties can be modified via doping to produce increasingly fluorescent CDs after appropriate purification. Herein, doped CDs were synthesized in four bottom-up methods for comparison using sucrose or citric acid as carbon precursors. Varying hetero-atom dopants (N, S, B) were used in differing molar ratios. The pH-dependent fluorescence and fluorescent quantum yield (QY) were measured for each sample. Characterization was conducted using Fourier-Transform Infrared Spectroscopy (FT-IR) for functional group identification, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) for sizing, and Ultraviolet-visible Spectroscopy (UV-vis) and fluorescence spectroscopy for optical properties. The digestive microwave method was determined to be the best performing, with nitrogen as the hetero-atom dopant which produced the highest fluorescing CDs. All nitrogen-doped carbon dots (NCDs) demonstrated pH-dependent fluorescence with increased fluorescence from pH 7-13. Overall, citric acid-based nitrogen-doped carbon dots (NCD-ca) with a carbon-to-dopant molar ratio of 1:6 demonstrated the highest QY of 19% in pH 11. Therefore, NCDs, as prepared, may serve as cost-effective fluorescent pH sensors
The Synthesis and Characterization of Pb(II) Cyanoximates
No full textA new series of Pb(II) cyanoximates were synthesized and characterized by elemental analysis (C, H, N, S), IR spectroscopy, thermal analysis, and X-ray crystallography. The goal was to synthesize compounds with a PbL2 (L= selected known chelating cyanoximes) composition for use as potential new non-linear optical (NLO) materials, specifically second harmonic generators (SHG), which must belong to non-centrosymmetric space groups. A desktop procedure using Pb2+ is chosen due to its typically active 6s2 lone pair of electrons, which are known to distort central polyhedra. A 1:2 ratio of Pb(II) to ligand were used to synthesize bulk products and grow crystals for structural determination. Bulk product resulted with 3 compounds with the desired PbL2 structure but unable to confirm non-centrosymmetric space group due to lack of single crystals for XRD analysis. Thus, crystal growth using a variety of methods became the main objective, although this proved difficult due to hydrolysis occurring on both the lead and ligand sides. Lead hydrolysis appears to dominate, as those fragments are present in most crystal structures. Overall, 30 promising crystals were analyzed resulting with six different lead/ ligand determined structures. The H(2PCO) ligand was the most successful system with three different structures. Crystal data revealed dimeric structure of Pb{(H2PCO)(2PCO)2 · H2O} with one 2PCO- anion in cis-syn orientation, which has never been seen before with this ligand, forming 6-member ring in chelation while acting as a μ-2 bridge. The only structure determined exclusively containing lead/ligand was Pb{(H2PCO)2(2PCO)2}and the only compound without active lone pair of electrons. Other structures determined were Pb3(2PCO)4(NO3)2, Pb3(OH)(NO3)(DCO)4, Pb4(OH)3(NO3)2(PiPCO)3(H2O), and one hydrolysis product from H(ECO) reaction, K2[Pb3(AACO)4(H2O)]2. The Pb(II) lead centers in crystal growth had high coordination with multiple lead centers, ligands acting as bridges, and invasion of spectator ions resulting in much more complex structures than desired, all belonging to centrosymmetric space groups. Unexpected results showed three products have properties of high-energy compounds, which violently decompose with release of significant heat and kinetic energy. Compared to known high-energy compounds these have high potential for use as heat-triggered actuators
England\u27s Fairest Creatures
No full textSet in 1616 Jacobean England, surrounding a tragic chamber pot incident, the place setting of the small fishing town of Lechlade, England, begins our story. From generations of fisherman, Elias Eaton, is the first Eaton not to bear a son. Instead, his fierce daughter in her mid-twenties, Julia, our protagonist, helps her father at the docks daily. Although Julia is a champion for women of her time, she dreams of there being something more out there for her than the town that has shackled Eatons for centuries. Julia’s mother, Sybil, is the daughter to the town baker. Her literate father taught her to write, so she taught Julia in secrecy. Sybil runs the business of Elias’s fishery along with trying and writing new recipes which she sells weekly at the market with her husband’s catch. Since the Eatons are fairly stable middle class English citizens, Sybil can not only maintain the nurturing of her own family, but she also offers nightly meals to the poor for trade. A button can get you a mutton at the Eatons’. Julia resents her parents for, what she believes, are seemingly passionless self-establishings in the world. Their love was like a poem, and they were content with their trades. The same could not be said for Julia. Instead, she desires to write, like Shakespeare. She pours over her own poetry, attempts at prose, and faulty Shakespeare quartos in an attempt to procure copies worth studying. The way Shakespeare explores the depths of his characters’ minds—their inner turmoil—resonates with Julia in a way she cannot escape. After dropping a full chamber pot on a famous actor’s head, later to be revealed as Shakespeare’s closest friend, rendering him fatally wounded, Julia is thrust into the start of a journey that could potentially be the key to helping her understand the Eaton melancholy that binds her. Perhaps what feels like an all-consuming curse is otherwise our protagonist’s greatest gift
High performing ensemble of convolutional neural networks for insect pest image detection
No full textPest infestation is a major cause of crop damage and lost revenues worldwide. Automatic identification of invasive insects would significantly speed up the recognition of pests and expedite their removal. In this paper, we generated ensembles of CNNs based on different topologies (EfficientNetB0, ResNet50, GoogleNet, ShuffleNet, MobileNetv2, and DenseNet201) optimized with different Adam variants for pest identification. Two new Adam algorithms for deep network optimization based on DGrad are proposed that introduce a scaling factor in the learning rate. Six CNN architectures that vary in their optimization function were trained on the Deng (SMALL), large IP102, and Xie2 (D0) pest data sets. Ensembles were compared and evaluated using several performance indicators. The best performing ensemble, which combined the CNNs using the different Adam variants, including the new ones proposed here, competed with human expert classifications on the Deng data set and achieved state of the art on all three insect data sets: 95.52% on Deng, 74.11% on IP102, and 99.81% on Xie2. Additional tests were performed on data sets for medical imagery classification that further validated the robustness and power of the proposed Adam optimization variants. All MATLAB source code is available at https://github.com/LorisNanni/
Optimal stochastic Bernstein polynomials in Ditzian–Totik type modulus of smoothness
No full textWe introduce a family of symmetric stochastic Bernstein polynomials based on order statistics, and establish the order of convergence in probability in terms of the second order Ditzian–Totik type modulus of smoothness on the interval [0,1], which epitomizes an optimal pointwise error estimate for the classical Bernstein polynomial approximation. Monte Carlo simulation results (presented at the end of the article) show that this new approximation scheme is efficient and robust