Precompetitive anxiety (PCA) is problematic for young gymnasts and may have an influence on a multitude of factors like self-confidence, perceived level of self-efficacy, and athlete's performance in a competition. The objective of this 2-part study was to discover how earlier competitive experience influences the young gymnasts' level of anxiety, perception of control, and self-efficacy. An additional goal was to explore the potential impact of Guided imagery (GI) and Autogenic training (AGT) in reducing precompetitive anxiety. In the first study, 80 USAG Junior Olympic female gymnasts between the ages of 7 and 16 (40 compulsory level and 40 optional level) participated. The purpose was to test differences in levels of PCA, locus of control, and self-efficacy among optional level and compulsory level gymnasts. An independent samples t test and a Mann-Whitney nonparametric test showed that optional level gymnasts had higher cognitive anxiety, lower confidence level, and higher internal locus of control compared with compulsory level gymnasts, with no significant mean difference in somatic anxiety and self-efficacy. For the second study, 30 participants were divided into 3 treatment groups: (a) AGT group, (b) GI group, and (c) control group. Results of repeated measure ANOVAs revealed that mean anxiety scores decreased over time for the autogenic group as compared to the control and guided imagery group. The internal LOC mean scores were lower for the autogenic group, compared to the other groups, but internal locus of control did increase over time for the autogenic group. The social significance of this study suggests that enhanced performance and enjoyment in sports may allow athletes to remain active in sports while teaching them life-long strategies to reduce anxiety and stress in their lives.

As an exploratory, developmental injury intervention study, this research investigated the efficacy of providing psychological intervention in the form of relaxation and guided imagery to a group of orthopedic patients recovering from major knee surgery. Utilizing a prospective, experimental research design with 30 subjects randomly assigned to either an intervention, placebo, or control group, this study employed physiological as well as psychological outcome measures. Intervention consisted of 10 individual mental practice sessions for intervention group members as an adjunct to physical therapy. Content of these sessions was intentionally designed to facilitate physiotherapy goals. Imagery protocols with which to deliver these standardized sessions were also designed to directly parallel established physical rehabilitation protocols. Placebo group participants were exposed to nonspecific intervention factors of attention and support, while control group members completed their physical therapy as usual. Results of this study revealed that for this sample of anterior cruciate ligament (ACL) orthopedic patients, psychological injury intervention in the form of relaxation and guided imagery contributed to statistically significant better physical and psychological outcomes. Strength and extension improvement, as well as reduction in state, trait, and reinjury anxiety, were superior for the intervention group as compared to placebo and control groups from preintervention (2 weeks postsurgery) to post-intervention (24 weeks postsurgery). Other benefits of the intervention, according to subject self-report, included pain and stress management, empowerment, control of recovery, and overall body wellness . Implications of these research findings are discussed, as well as suggestions offered for subsequent injury intervention research.

Clustered regularly interspaced short palindromic repeats (CRISPR) are derived from a bacterial and archaeal adaptive immune system. The core enzymes of CRISPR are RNA-guided endonucleases that sequence-specifically cleave foreign double-stranded DNA. Improving and controling the properties of the CRISPR system is a crucial step in advancing the therapeutic potential of CRISPR technology. Several classes of these enzymes exist and are being adapted for biotechnology, such as genome engineering. Cas12a (Cpf1) is a Type V CRISPR-associated (Cas) enzyme that naturally uses only one guide RNA, in contrast to Type II CRISPR-Cas9 enzymes. Thus, Cpf1 may represent a simpler, more practical tool for applications such as gene editing and therapeutics. This dissertation comprises four related studies in this area. To better understand the functional requirements for Cpf1-crRNA interaction and develop modified crRNAs suitable for synthetic biology and therapeutic applications, the first study performed nucleotide substitutions in the crRNA. It focused on the protein-interaction motif of the crRNA by incorporating base changes at the 2ʹ position that alter hydrogen-bonding capacity, sugar pucker, and flexibility. DNA substitutions in RNA can probe the importance of A-form structure, 2ʹ-hydroxyl contacts, and conformational constraints within RNA-guided enzymes. In addition, Chemical modifications include 2'-deoxy, 2'-fluoro, 2'- deoxy-arabinonucleic acid, and oxepane. Our study discovered that 2'-fluoro maintains the A-form structure and is compatible with AsCpf1 activity. Biochemical endonuclease activity, gene editing efficiency, Cpf1 binding affinity, and ribonucleoprotein stability were used to assess the tolerance and effects of modification. Characterizing structure-function requirements for Cpf1-crRNA interaction will facilitate better design and tuning of Cpf1 enzymes. The second study established a FRET-based assay in collaboration with a computational collaborator to identify small molecule inhibitors predicted by virtual docking and simulations. This study aims to lay the foundation for efficient, safe implementation of CRISPR-Cpf1. The third study used chemically modified Cas9-guide RNAs to offset known weaknesses of CRISPRi. It takes advantage of the high binding affinity and nuclease resistance of modified guides to potentially reduce the required components for CRISPRi.

The hotspot temperature of disc windings has a close relation with the transformer age. In oil immersed transformers, oil guides are applied generally to enhance the cooling effects for disc windings. In some cases disc windings without oil guides are used. However, the lack of oil guides is expected to result in a more complicated thermal behavior of the windings, making it more difficult to predict the location and strength of the hotspot temperature (i.e. the hottest temperature in the winding). To get an improved understanding of the thermal behavior, a CFD study has been performed.  This article describes the implementation of CFD simulation for 2D axisymmetry models without oil guides, and then analyzes the results of a series of parametric studies to see the sensitive factors influencing the cooling effects. These parameters include radial disc width, inlet mass flow rate, horizontal duct height, vertical duct width and the inlet/outlet configurations. Three main characteristics, the hotspot temperature, the location of the hotspot and the number of oil flow patterns are detected to describe the thermal performance.

Composite materials have increasingly been used as an alternative to metals and other isotropic materials for primary structural components in aerospace industries. Unlike traditional isotropic materials, composite materials are known to have complex internal microstructures. Therefore, it is essential to develop methods for the inspection, evaluation, and monitoring of composite materials. Ultrasonic-guided waves and, more precisely, Lamb waves have proven to be an efficient and accurate technique for the non-destructive testing. Since guided waves are dispersive and multimodal, it is important to develop a practical method to manipulate Lamb waves to achieve better structural health monitoring and non-destructive inspection results. There are minimal studies involving manipulating guided waves for the inspection of composite materials. Moreover, the currently proposed methods to manipulate Lamb waves are complex and costly. The objective of this dissertation research is to offer practical and straightforward methods with a simple design to control Lamb waves using additively manufactured lenses used as superstrates on composite plates. This dissertation is organized in three major parts. Part I focuses on the Lamb wave propagation in composite plates with different lay-up and plate orientations. Finite element simulations were performed to investigate the behavior of Lamb wave propagation in different plates. A semi-finite element approach was used to derive the dispersive curves in each plate. In Part II, a lap-joint study was conducted to investigate the interaction of Lamb waves in the lap joint regions. Two different lap joints were considered, composite-aluminum and composite-plastic. In each lap joint the thickness of the top surface (aluminum or plastic) is continuously increased. In Part III, additively manufactured lenses are designed to modulate the wavefront of Lamb waves in thick composite plates. The first design is a prism-shaped lens proposed to steer Lamb waves to a targeted direction. Multiple prism designs are considered to offer a flexible steering direction by either changing the prism thickness or the wedge angle. The second design is a plano-concave shaped lens designed to focus the Lamb wave at a targeted focal point. This dissertation research will provide a clear understanding of Lamb wave propagation in anisotropic material, anisotropic-isotropic lap joints, and wavefront modulation on anisotropic material using additively manufactured lenses. This approach contributes to the development of better quality SHM for online monitoring systems.

State exploration in directed software model checking is guided using a heuristic function to move states near errors to the front of the search queue. Distance heuristic functions rank states based on the number of transitions needed to move the current program state into an error location. Lack of calling context information causes the heuristic function to underestimate the true distance to the error; however, inlining functions at call sites in the control flow graph to capture calling context leads to exponential growth in the computation. This paper presents a new algorithm that implicitly inlines functions at call sites to compute distance data with unbounded calling context that is polynomial in the number of nodes in the control flow graph. The new algorithm propagates distance data through call sites during a depth-first traversal of the program. We show in a series of benchmark examples that the new heuristic function with unbounded distance data is more efficient than the same heuristic function that inlines functions up to a certain depth.

BACKGROUND: Static and dynamic dental implant guidance systems have established themselves as effective choices that result in predictable and relatively accurate dental implant placement. Generally, studies assess this accuracy using a postoperative CBCT, which has disadvantages such as additional radiation exposure for the patient. This pilot study proposed a scanbody-agnostic method of implant position assessment using intraoral scanning technology and applied it as an accuracy test of robotically assisted dental implant placement using the Neocis Yomi. MATERIALS AND METHODS: All of the robotically assisted dental implant surgery was performed in the Postdoctoral Periodontology clinic at Boston University Henry M. Goldman School of Dental Medicine. Completely edentulous patients were excluded. A total of eleven (11) implants were included in the study, eight (8) of which were fully guided. An optical impression of each implant position was obtained using a CEREC Omnicam (SW 5.1) intraoral scanner. Each sample used either a DESS Lab Scan Body or an Elos Accurate Scan Body as a means to indirectly index the position of the implant. A comparison of planned implant position versus executed surgical implant position was performed for each placement using Geomagic Control X software. Global positional and angular deviations were quantified using a proposed scanbody-agnostic method. Intraoral directionality of deviation was visually qualified by the author (D.K). RESULTS: Mean global positional deviations at the midpoints of the top of each scanbody were 1.7417 mm in the partially guided samples and 1.1300 mm in the fully guided samples. Mean global positional deviations at the midpoints of the restorative platforms of each implant were 1.3142 mm in the partially guided sample and 1.27045 mm in the fully guided samples. Mean global positional deviations at the midpoints of the apex of each implant were 1.455 mm in the partially guided samples and 1.574 mm in the fully guided samples. Mean angular deviations were 3.7492 degrees in the partially guided samples and 2.6432 degrees in the fully guided samples. CONCLUSION: Within the sample size limitations, robotically assisted dental implant surgery offers similar implant placement accuracy compared to published static and dynamic implant placement guidance systems. Intraoral optical assessment of dental implant position used in this study allows comparable analysis to other methods without requiring additional exposure to radiation and should be considered the default method of assessing guidance accuracy.

THIS STUDY INVESTIGATED THE EFFECTS OF THE TEACHER'S USE OF GUIDED INQUIRY IN A FIFTH GRADE SCIENCE CLASSROOM. INQUIRY IS SUPPORTED BY THE NATIONAL RESEARCH COUNCIL(2000), AND INDICATES THAT ALL STUDENTS SHOULD DEVELOP THE ABILITIES NECESSARY TO DO SCIENTIFIC INQUIRY AND DEVELOP UNDERSTANDINGS ABOUT SCIENTIFIC INQUIRY (P.21). THIS STUDY WAS A QUALITATIVE ACTION RESEARCH DESIGN, FOCUSING ON SEVENTEEN STUDENTS AND THEIR RESPONSES TO A GUIDED INQUIRY METHOD OF SCIENCE INSTRUCTION ON MATTER, ENERGY AND MOTION, AND EARTH AND SPACE. AN ANALYSIS OF STUDENTS' PERFORMANCE AND STUDENTS' ATTITUDES ABOUT SCIENCE IN THE CLASSROOM WAS CONDUCTED ABOUT EACH UNIT OF INSTRUCTION. THE 5-E MODEL OF GUIDED INQUIRY WAS USED TO ELICIT MEANINGFUL UNDERSTANDINGS WHILE COMPLETING THE UNITS OF MATTER, ENERGY AND MOTION, AND EARTH AND SPACE. STUDENTS WORKED IN COOPERATIVE GROUPS TO SUPPORT LAB ACTIVITIES, WHICH REQUIRED EACH MEMBER TO PARTICIPATE IN THE INVESTIGATIONS, PROJECTS, AND PRESENTATIONS. STUDENTS KEPT JOURNALS, RECORDED THEIR FINDINGS, AND WROTE RESPONSES ABOUT THEIR FINDINGS AND FEELINGS ON THE ACTIVITIES IN WHICH THEY WERE ENGAGED. STUDENTS' ATTITUDES WERE AFFECTED POSITIVELY BY THE USE OF GUIDED INQUIRY IN LEARNING SCIENCE. STUDENTS' PERFORMANCE FOR LAB ACTIVITIES WAS ALSO POSITIVE AND WAS SUPPORTED BY STUDENTS' RESPONSES IN JOURNALS, TEACHER OBSERVATIONS, AND PERFORMANCE TASKS. THIS STUDY SUPPORTS GUIDED INQUIRY IN THE SCIENCE CLASSROOM FOR IMPROVING STUDENTS' ATTIDUES AND STUDENTS' PERFORMANCE DURING CLASSROOM ACTIVITES.

Guided mode resonant (GMR) structures are optical devices that consist of a planar waveguide with a periodic structure either imbedded in or on the surface of the structure. The resonance anomaly in GMR structures has many applications as dielectric mirrors, tunable devices, sensors,and narrow spectral band reflection filters. A desirable response from a resonant grating filter normally includes a nearly 100% narrowband resonant spectral reflection (transmission), and a broad angular acceptance at either normal incidence or an oblique angle of incidence. This dissertation is a detailed study of the unique nature of the resonance anomaly in GMR structures with two-dimensional (2-D) periodic perturbation. Clear understanding of the resonance phenomenon is developed and novel 2-D GMR structures are proposed to significantly improve the performance of narrow spectral filters. In 2-D grating diffraction, each diffracted order inherently propagates in its distinct diffraction plane. This allows for coupled polarization dependent resonant leaky modes with one in each diffraction plane. The nature of the interaction between these non-collinear guides and its impact on spectral and angular response of GMR devices is investigated and quantified for 2-D structures with rectangular and hexagonal grids. Based on the developed understanding of the underlying phenomenon, novel GMR devices are proposed and analyzed. A novel controllable multi-line guided mode resonant (GMR) filter is proposed. The separation of spectral wavelength resonances supported by a two-dimensional GMR structure can be coarse or fine depending on the physical dimensions of the structure and not the material properties. Multiple resonances are produced by weakly guided modes individually propagating along multiple planes of diffraction. Controllable two-line and three-line narrow-band reflection filter designs with spectral separation from a few up to hundreds of nanometers are exhibited using rectangular-lattice and hexagonal-lattice grating GMR structures, respectively. Broadening of the angular response of narrow band two-dimension guided mode resonant spectral filters, while maintaining a narrow spectral response, is investigated. The angular response is broadened by coupling the diffracted orders into multiple fundamental guided resonant modes. These guided modes have the same propagation constant but propagating in different planes inherent in multiple planes of diffraction of the 2-D gratings. The propagation constants of the guided resonant modes are determined from the physical dimensions of the grating (periodicity and duty cycle) and the incident direction. A five-fold improvement in the angular tolerance is achieved using a grating with strong second Bragg diffraction in order to produce a crossed diffraction. A novel dual grating structure with a second grating located on the substrate side is proposed to further broaden the angular tolerance of the spectral filter without degrading its spectral response. This strong second Bragg backward diffraction from the substrate grating causes two successive resonant bands to merge producing a resonance with symmetric broad angular response.

This work is divided into two main parts. In the first part (chapters 2-7) we consider the nonlinear response of nano-particle colloidal systems. Starting from the Nernst-Planck and Smoluchowski equations, we demonstrate that in these arrangements the underlying nonlinearities as well as the nonlinear Rayleigh losses depend exponentially on optical intensity. Two different nonlinear regimes are identified depending on the refractive index contrast of the nanoparticles involved and the interesting prospect of self-induced transparency is demonstrated. Soliton stability is systematically analyzed for both 1D and 2D configurations and their propagation dynamics in the presence of Rayleigh losses is examined. We also investigate the modulation instability of plane waves and the transverse instabilities of soliton stripe beams propagating in nonlinear nano-suspensions. We show that in these systems, the process of modulational instability depends on the boundary conditions. On the other hand, the transverse instability of soliton stripes can exhibit new features as a result of 1D collapse caused by the exponential nonlinearity. Many-body effects on the systems' nonlinear response are also examined. Mayer cluster expansions are used in order to investigate particle-particle interactions. We show that the optical nonlinearity of these nano-suspensions can range anywhere from exponential to polynomial depending on the initial concentration and the chemistry of the electrolyte solution. The consequence of these inter-particle interactions on the soliton dynamics and their stability properties are also studied. The second part deals with linear and nonlinear properties of optical nano-wires and the coupled mode formalism of parity-time (PT) symmetric waveguides. Dispersion properties of AlGaAs nano-wires are studied and it is shown that the group velocity dispersion in such waveguides can be negative, thus enabling temporal solitons. We have also studied power flow in nano-waveguides and we have shown that under certain conditions, optical pulses propagating in such structures will exhibit power circulations. Finally PT symmetric waveguides were investigated and a suitable coupled mode theory to describe these systems was developed.