Mechanical loading can modulate tissue plasticity and has potential applications in rehabilitation science and regenerative medicine. To safely and effectively introduce mechanical loads to human cells, tissues, and the entire body, we need to understand the optimal loading environment to promote growth and health. The purpose of this research was 1) to validate a limb vibration and compression system; 2) to determine the effect of limb vibration on neural excitability measured by sub-threshold TMS-conditioned H-reflexes and supra-threshold TMS; 3) to determine changes in center of pressure, muscle activity, and kinematics during a postural task following limb vibration; 4) to determine the effect of vibration on accuracy and long latency responses during a weight bearing visuomotor task. The major findings of this research are 1) the mechanical system presented in the manuscript can deliver limb vibration and compression reliably, accurate, and safely to human tissue; 2) sub-threshold cortical stimulation reduces the vibration-induced presynaptic inhibition of the H-reflex. This reduction cannot be attributed to an increase in cortical excitability during limb vibration because the MEP remains unchanged with limb vibration; 3) limb vibration altered the soleus and tibialis EMG activity during a postural control task. The vibration-induced increase in muscle activity was associated with unchanged center of pressure variability and reduced center of pressure complexity; 4) healthy individuals were able to accommodate extraneous afferent information due to the vibration interventions They maintained similar levels of accuracy of a visuomotor tracking task and unchanged long latency responses during an unexpected perturbation.

Previous research into the communication of people with amnesia found that they, and their familiar communication partners, used verbal play less frequently than pairs without amnesia (Duff et al., 2009). This study attempts to analyze an additional dimension of playful language use: partner response to verbal play. A rubric was developed to rate verbal play response on a 0-5 scale. The rubric was used to rate partner response in four communication pairs containing one partner with amnesia and one familiar communication partner; and four healthy pairs for comparison. The responses of the experimenter participating in the conversations were also rated. While the study found no differences between the two groups in terms of the familiar communication partners or the experimenter, the participants with amnesia received significantly lower overall scores than participants without amnesia. The participants with amnesia also produced a significantly lower proportion of responses with multiple turns than did healthy participants. This result adds to the body of evidence that memory disorders can affect social interaction. The rubric developed for this study suggests a possible direction for including partner response in analyses of conversational discourse.

Objectives: Evaluate and assess the effect of an innovative double layer, single application desensitizing/whitening technique on Nitrate penetration and total color change. Methods: Specimens were prepared from extracted caries free human molars (n=160). Teeth were randomly assigned into four groups: 100μl 25% hydrogen peroxide “Philips Zoom chairside” as control group (CTRL), double layer treatment of 20μl 5% potassium nitrate “Relief ACP, Philips oral care” and 100μl 25% hydrogen peroxide (DL20), double layer treatment of 40μl 5% potassium nitrate and 100μl 25% hydrogen peroxide (DL40), and one layer treatment of 40 μl 5% potassium nitrate (PN40). Spectrophotometric color measurements (Vita EasyShade) were done at base line (T0), one day (T1), and one month (T2) following the treatment. Nitrate penetration was measured using a nitrate/nitrite assay kit. Group comparisons of tooth color difference measurements, and nitrate penetration readings were made using the Kruskal-Wallis test. Adjustment was made for pairwise treatment comparisons using the Tukey method in conjunction with an overall 0.05 level of significance. Results: 160 teeth were used. Color difference (ΔE) results at (T1) and (T2) showed no significant difference among the CTRL, DL20, DL40 groups. But there was a statistical significant difference between those groups and the single layer (PN40) group (p

Location information is of extreme importance in every walk of life ranging from commercial applications such as location based advertising and location aware next generation communication networks such as the 5G networks to security based applications like threat localization and E-911 calling. In indoor and dense urban environments plagued by multipath effects there is usually a Non Line of Sight (NLOS) scenario preventing GPS based localization. Wireless localization using sensor networks provides a cost effective and accurate solution to the wireless source localization problem. Certain sensor geometries show significantly poor performance even in low noise scenarios when triangulation based localization methods are used. This brings the need for the design of an optimum sensor placement scheme for better performance in the source localization process. The optimum sensor placement is the one that optimizes the underlying Fisher Information Matrix(FIM) . This thesis will present a class of canonical optimum sensor placements that produce the optimum FIM for N-dimensional source localization N greater than or equal to 2 for a case where the source location has a radially symmetric probability density function within a N-dimensional sphere and the sensors are all on or outside the surface of a concentric outer N-dimensional sphere. While the canonical solution that we designed for the 2D problem represents optimum spherical codes, the study of 3 or higher dimensional design provides great insights into the design of measurement matrices with equal norm columns that have the smallest possible condition number. Such matrices are of importance in compressed sensing based applications. This thesis also presents an optimum sensing matrix design for energy efficient source localization in 2D. Specifically, the results relate to the worst case scenario when the minimum number of sensors are active in the sensor network. We also propose a distributed control law that guides the motion of the sensors on the circumference of the outer circle so that achieve the optimum sensor placement with minimum communication overhead. The design of equal norm column sensing matrices has a variety of other applications apart from the optimum sensor placement for N-dimensional source localization. One such application is fourier analysis in Magnetic Resonance Imaging (MRI). Depending on the method used to acquire the MR image, one can choose an appropriate transform domain that transforms the MR image into a sparse image that is compressible. Some such transform domains include Wavelet Transform and Fourier Transform. The inherent sparsity of the MR images in an appropriately chosen transform domain, motivates one of the objectives of this thesis which is to provide a method for designing a compressive sensing measurement matrix by choosing a subset of rows from the Discrete Fourier Transform (DFT) matrix. This thesis uses the spark of the matrix as the design criterion. The spark of a matrix is defined as the smallest number of linearly dependent columns of the matrix. The objective is to select a subset of rows from the DFT matrix in order to achieve maximum spark. The design procedure leads us to an interest study of coprime conditions on the row indices chosen with the size of the DFT matrix.

The purpose of this study was to examine secondary mathematics teachers' questioning, responses, and perceived influences upon their instructional decisions regarding questioning and response to students' ideas. This study also compared the questioning practices, responses, and influences of beginning teachers to more experienced teachers. Previous studies on teacher quality in mathematics education have focused on general characteristics of mathematics teachers' instructional practice including a broad range of instructional strategies. Little is known about mathematics teachers' questioning practices and responses to students' ideas that research has repeatedly reported are critical to student mathematics learning in secondary classrooms. Furthermore, it is not clear how different novice teachers are in questioning and responding to students from experienced teachers. This understanding can provide significant insights into teacher education programs for mathematics teachers. With those issues in mind, this study was designed to answer the following questions: (1) What similarities and differences exist in questioning patterns between novice and experienced teachers when guiding a classroom mathematical discussion? (2) What similarities and differences exist in responses to students during pivotal teaching moments between novice and experienced teachers when guiding a classroom mathematical discussion? (3) What perceived factors impact the responses teachers give to students' ideas, and how are these factors of influence different among novice and experienced teachers? This study employed a multiple case study research design to compare the questioning practices and responses of three beginning teachers and three experienced teachers. Multiple sources of data were collected, including two interviews (i.e., initial interview and follow-up interview) for each teacher, five days of classroom video footage for each teacher, and field notes by the researcher for each interview and observation. The researcher conducted initial interviews with each teacher to gain a general sense of the teacher's philosophy and use of questions in guiding classroom discussion. Five instructional days of observation followed the initial interview, and then the researcher conducted a follow-up interview by use of video-stimulated response. All interviews were transcribed verbatim for analysis. The data was analyzed mainly using the constant comparative method to identify regularities and patterns emerging from the data. Results showed differences between beginning and experienced teachers in the frequency and variety of questions asked. Although all teachers showed the largest number of questions in the Socratic questioning category, differences were prominent in the semantic tapestry and framing categories. Results regarding teacher responses to pivotal teaching moments showed that four teachers favored a procedural emphasis in their responses to students, and two teachers used responses to direct students to make clear connections within or outside of mathematics. Perceived influences identified include: (1) reflection on experience and mathematical knowledge for teaching, (2) time, and (3) relationship with students, teachers, and parents, and knowledge of student background. Practicing teachers can expand the types of questions they use in the classroom, making particular efforts to include those areas that this study showed to be most lacking: semantic tapestry questions that help students build a coherent mental framework related to a mathematical concept, and framing questions that help frame a problem and structure the discussion that follows. The comparison between beginning and experienced teachers also shed light on important practices for teacher education. The beginning teacher participants from this study had no trouble noticing pivotal teaching moments in their lessons but were less developed in their responses to them. Recommendations for mathematics teacher education programs are to provide opportunities to develop content, pedagogical knowledge including specific instruction on questioning strategies, and also to provide parallel field experiences where pre-service teachers can apply the knowledge and skill they are learning.

Service-learning is the combination of traditional teaching methods with field-based learning and critical reflection (Hurd, 2008) and is popular in first-year composition (Deans, 2001). However, academic research on service-learning in first-year composition is relatively scarce and the most frequently-cited scholarship is at least a decade old (Adler-Kassner, Crooks & Watters, 1997; Deans, 2001; Haussamen, 1997). This study seeks to contribute to the scholarship on service-learning in first-year composition by exploring how stakeholders, including the instructor, the students, and the community partner, perceive the project's purposes and outcomes. To complete the service-learning requirement for the course in this study, students conduct a bystander intervention workshop for a small group of their peers that focuses on cultural humility and sexual assault prevention. In preparation for the service-learning project, students attend a bystander intervention training conducted by the [Women's Advocacy Program], a center on campus that specializes in violence prevention, LGBTQA rights advocacy, and promoting cultural humility on campus and in the surrounding community. In order to explore participants' experiences with the project, data was gathered through participant observation, semi-structured interviews, and relevant artifacts, such as student work and course materials. In total, the study includes twenty-one participants, including the instructor, the community partner, and 19 students. Of the 19 students enrolled in the course, this research focuses on the experiences of five key informants (Bogdan & Bilken, 1997), who are referred to as “focal students” throughout the study. The findings of this study have implications for first-year composition instructors who engage in service-learning. Echoing previous research, this study finds that the relationship between the community partner and the instructor is an important factor in service-learning. Specifically, in this study, the instructor and the community partner design, implement, and assess the service-learning project collaboratively and have adapted the project over five semesters to ensure that it meets both their needs. The instructor and the community partner cite their collaboration as one of the reasons the project is successful. This study also reflects previous findings that indicate service-learning is more successful when it is integrated into the course curriculum. Students in this study feel that the project seems somewhat “separate” from the course, and perceive this lack of integration between the project and the course as one of the project's biggest weakness. A key finding of this study is that stakeholders in a service-learning project may not need to recognize or understand one another's perspectives about the project's purposes or outcomes in order for the the project to be successful. Previous research has suggested that service-learning projects are more likely to be successful if stakeholders understand one another's expectations for the project (Bringle, Clayton, & Hatcher, 2012; Deans, 2001), but this study suggests that this understanding might not be as essential to a service-learning project's success as previously thought. This study finds that participants perceive the project's purposes differently and have varying expectations about its outcomes. They make different and occasionally contradicting claims about which aspects of the project are effective or ineffective and they often indicate that they don't fully understand one another's perspectives on the project. Participants perceptions of the project are consistently divergent with one exception: they believe the instructor should continue teaching the project in future courses because they believe that the project is beneficial to their community, which suggests that participants don't need to understand one another's perspectives in order for the project to be successful.

Background & Purpose Approximately 50β of children born with cleft lip and/or palate (CL/P) will need speech and language intervention (Lockhart, 2003). Speech difficulties are related to poorer academic performance, higher risk of retention in younger grades, and greater risk of being bullied or having a low self-esteem (Byrd, 1994; Lockhart, 2003). Since parents are the primary decision makers when it comes to treatment for their child, how closely do parents' perceptions of speech, appearance, and emotional consequences match the perception of their child? This study assessed differences in perceptions between parents and children with CL/P regarding speech, the emotional impact of having a cleft, and quality of life. Methods & Description Twenty parent-child dyads were recruited at a University based cleft palate clinic. The children were between 7 and 17 years of age, with a diagnosis of cleft palate, cleft lip and alveolus, submucous cleft only, or cleft lip and palate. During a routine clinic appointment, the child and a parent/legal guardian completed the VPI Effects of Life Outcome (VELO) Survey. Parents and children completed the VELO Survey separately to facilitate open, unbiased responses, especially regarding sensitive issues such as facial appearance and emotional health. Results Overall, parents and their affected children did not view the child's speech significantly differently. A Wilcoxon signed rank test found that the differences between parent and child responses were not significant (p=0.3979). Gender, age, and cleft type were not found to have statistically significant impact on differences between parent and child scores. The VELO Survey is divided into five main sections. This study identified the subsection relating to speaking in various situations as having a significantly greater parental concern when compared across all VELO subsections. After applying a Bonferroni multiple comparison adjustment to control the type error rate at 0.05 for all five subsections, a statistically significant relationship was found indicating higher parent ratings than their child in this subsection (p=0. 0.0184). Speech-language pathologist ratings showed a statistically significant linear relationship with the child total VELO scores (p=0.0116), and with parent total VELO scores (p=0.0009). This means that a higher score on the VELO by the parent or the child, and a lower SLP rating, both indicate lower severity of impact of the cleft disorder on the child's life. Conclusion While parents, children, and the speech-language pathologist often agreed with each other in their rating how having a cleft affected the child's life, significant differences did exist between some parent-child dyads. These differences have important clinical implications, primarily the importance of including both parents and children in discussions of the impact of the cleft condition and treatment options.

Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants that have been associated with a myriad of negative human health effects. These man-made compounds were used throughout most of the 20th century and although their intentional production has since been banned and their use limited to closed systems, their prevalence in the environment remains a factor in disease states for exposed populations. The worldwide levels of PCBs has been declining, however, there is evidence for renewed sources of these compounds. The presence of PCBs with lower numbers of chlorine atoms (LC-PCBs) have been verified as unintentional byproducts in paints and pigments, the decomposition of PCB waste, or the recycling or disposal attempts of PCB-laden materials. While exposure to the higher chlorinated congeners (HC-PCBs) is often attributed to the consumption of contaminated water or fatty animal meat, a significant route of exposure to the airborne LC-PCBs is through inhalation. These semi-volatile compounds have been detected in high quantities in both indoor and outdoor air in urban and rural communities, and their presence is pronounced in older buildings (e.g., homes and schools). When compared to HC-PCBs, LC-PCBs are more highly susceptible to metabolic transformations, and recently their sulfated metabolites have gained much interest. Although the sulfation of xenobiotics often is considered a route for their removal from the body, a previous study of Sprague-Dawley rats treated with 4-chlorobiphenyl (PCB 3) resulted in the substantial formation of sulfated metabolites (i.e., hydroxylation followed by sulfation of the LC-PCB). This metabolic route accounted for more than half of the treatment dose. Furthermore, LC-PCB sulfates have been shown to bind to the human serum protein, transthyretin, in vitro. Of the health effects associated with PCB exposure, neurotoxicity has been well established through various laboratory and epidemiological studies. It is proposed that the dopaminergic system lies at the core of the observed cognitive, motor, and intellectual dysfunction observed in exposed populations, especially in children exposed perinatally. Interestingly, PCB exposure has been linked to Parkinson's disease (PD) etiology, which is marked by a substantial loss of dopaminergic neurons. This thesis describes studies on the binding of selected LC-PCBs and their hydroxylated and sulfated metabolites to human serum albumin (HSA), the most abundant protein in human serum. The displacement of fluorescent probes, selective for the two major drug binding sites of HSA, indicates that LC-PCB sulfates generally bind to HSA with such affinity that is equal to or greater than that for the LC-PCBs or OH-LC-PCBs This work also included a study of the selective toxicity of these compounds to dopaminergic neuronal cells. The selective toxicity of these compounds was studied in a series of immortalized cell lines (i.e., two neuronal cell lines: the rat midbrain-derived N27 cell line, the human neuroblastoma-derived SH-SY5Y cell line, and the human liver-derived HepG2 cell line). The assessment of toxicity by MTT reduction and LDH release in these cellular models indicated that hydroxylated and sulfated metabolites of LC-PCBs exhibited toxicity that was selective to neuronal cells and, in most cases, selective for the dopaminergic neuronal cells. Furthermore, HPLC analysis of the distribution of the compounds from the extracellular medium into the cellular milieu indicated that the observed toxicity may be due in some cases to selective transport and further metabolism. This work contributes to understanding the neurotoxicity of LC-PCB hydroxylated and sulfated metabolites and the role that binding to serum proteins may play in it. Furthermore, it emphasizes the need for future studies on the effects that metabolism, particularly sulfation, may play in the disposition of LC-PCB congeners as it pertains to their metabolism, retention, and toxic effects.

Currently, there exists a great deal of uncertainty regarding atmospheric aerosols and the role that they play within the Earth’s atmosphere. It is known that atmospheric aerosols can play a role in the Earth’s climate by scattering and absorbing solar radiation or acting as a cloud condensation nuclei. The purpose of this work is to obtain an improved understanding of the chemistry of atmospheric aerosols to better determine their impacts the environment, air quality, and climate. This work revolves around one specific type of atmospheric aerosol, i.e. sea spray aerosol. Sea spray aerosol is generated via breaking waves, through wind-driven mechanisms. Ocean water covers roughly 71% of the Earth’s surface, and from this over 1300 Tg of sea spray aerosols is emitted into the atmosphere every year. However, until recently, the study of sea spray was very challenging and often inconclusive due to the inability to filter background particles out. In this work, the understanding of sea spray aerosol is progressed by taking a two-pronged approach. First, this work focuses on the study of model systems of simple ocean surfactants and NaCl and the change in chemistry that occurs when the two are in the presence of each other. Second, sea spray samples generated during a biological bloom are isolated and analyzed. Using this two pronged approach, it is shown that model systems can provide supporting evidence for hypotheses created from trends discovered in more complex samples. Finally, common aerosol generation, storage, and analysis techniques are studied in order to improve our understanding of their effects on aerosol particles.

Clear evidence shows a relationship between working in swine facilities and developing respiratory illnesses. Health effects have been associated with exposures to the combination of dust, ammonia, and carbon dioxide (CO2). This study examined whether room concentrations of combustion gases could be improved by changing the in-room vented heaters common to animal production operations to heaters that vent combustion gases outside. Concentrations of CO2 and carbon monoxide (CO) were monitored during two winter seasons, with the 2013-14 season using the traditional gas-fired heater (Guardian 60, L.B.White Co.) and the 2014-15 winter using new vented heaters (Effinity93, Modine Manufacturing Co.) Direct-reading CO (VRAE, Rae Systems) and CO2 (ToxieRAE Pro, Rae Systems) monitors were deployed at fixed stations throughout the farrowing barn to measure gas concentrations. Differences in mean gas concentrations between heater types, as well as the relationship between CO2 and temperature, sow, and piglet count, were evaluated using linear regression. Carbon dioxide concentrations exceeded industry recommended limits (1540 ppm) on all sample days (N=18) with the standard in-room vented heaters in operation: concentrations averaged half of the TLV (2500 ppm). With the new vented heaters, 24-hour averaged CO2 concentrations exceeded industry recommended limits on only three out of 20 sample days: concentrations averaged 1400 ppm. The new heater significantly reduced CO2 by 44% and CO by 60% from 2.0 to 0.8 ppm (p2=0.75) between CO2 and production factors (temperature, sow and piglet count) for the new heater: CO2 (ppm) = 482 - 22.4(Temp °C) + 43(# sow) + 5.6(# piglet). Similar analysis for the old heater identified similar trends but substantially different intercept (1700 ppm) and temperature factor (-36.9). While CO2 is still generated from swine respiration, we found significant reductions in room concentrations with the simple replacement of commonly used equipment. Future work will include an assessment of the longevity of these heaters in the swine barn environment