Academic literature on the topic 'New methods of tooth movement'

Recent years have seen a rapid growth in movement research owing to new technologies contributing to the miniaturization and reduced costs of tracking devices. Similar trends have occurred in how environmental data are being collected (e.g., through satellites, unmanned aerial vehicles, and sensor networks). However, the development of analytical techniques for movement research has failed to keep pace with the data collection advances. There is a need for new methods capable of integrating increasingly detailed movement data with a myriad of contextual data - termed context aware movement analysis (CAMA). CAMA investigates more than movement geometry, by including biological and environmental conditions that may influence movement. However, there is a shortage of methods relating movement patterns to contextual factors, which is still limiting our ability to extract meaningful information from movement data. This thesis contributes to this methodological research gap by assessing the state-of-the art for CAMA within movement ecology and human mobility research, developing innovative methods to consider the spatio-temporal differences between movement data and contextual data and exploring computational methods that allow identification of patterns in contextualized movement data. We developed new methods and demonstrated how they facilitated and improved the integration between high frequency tracking data and temporally dynamic environmental variables. One of the methods, multi-channel sequence analysis, is then used to discover varying human behaviour relative to weather conditions in a large human GPS tracking dataset from Scotland. The second method is developed for combing multi-sensor satellite imagery (i.e., image fusion) of differing spatial and temporal resolutions. This method is applied to a GPS tracking data on maned wolves in Brazil to understand fine-scale movement behaviours related to vegetation changes across seasons. In summary, this thesis provides a significant development in terms of new ideas and techniques for performing CAMA for human and wildlife movement studies.

Freshwater turtles are among the most threatened groups of taxa globally, and the bog turtle, Glyptemys muhlenbergii is among the most imperiled in North America. In Virginia, USA, bog turtles are restricted to occupying Appalachian Mountain fens. Fens are naturally small and fragmented wetlands characterized by elevated water tables and an open canopy. Although there is a strong need to document and monitor populations of bog turtles, efforts to do so are often limited by the low detection of the species. The first objective of this thesis was to assess proposed methodologies for locating populations of turtles on the landscape. My first chapter assessed a previously-developed habitat distribution model for bog turtles using an occupancy modeling approach. I conducted 216 surveys of 49 discretely predicted patches of habitat, recording conditions such as weather, size of wetland and time of year, hypothesized to affect detection during each survey. In addition, I assessed factors including stream entrenchment, grazing presence and surrounding impervious surfaces for each surveyed patch to identify data sources that could improve future models or better assess sites. I found that sites with larger total wetland area had higher detection per survey, possibly due to larger sites having higher densities of turtles (among other explanations), and that sites with higher amounts of impervious surfaces within their drainage were less likely to be occupied. In addition to the bog turtle, several plant species also occur in mountain fens. These species usually have a locally rare distribution or are disjuncts from a more northern latitude. Because of these traits, a high diversity of specialist plants may be indicative of a fen with a robust hydrology that has historically been less disturbed. Past site quality analyses have proposed using indicator diversity to assess sites, but no study has found if these species to tend to co-occur. My second chapter examines this hypothesis. I first chose a list of plant species that would most likely have habitat requirements similar to those of turtles. Then, at 12 sites, 6 with turtles and 6 without, I conducted a complete floral inventory. I first tested community-wide differences between the floral communities of these sites and found no difference, but when I narrowed my analysis to examining occurrence patterns of plant species determined a priori to be fen specialists and Glyptemys muhlenbergii, a pattern of co-occurrence was found. This lends support to the idea that indicator plants could be used as a tool to better evaluate sites that may have bog turtles. My last chapter investigated movement of bog turtles in a landscape impacted by anthropogenic development. Movement of turtles between adjacent sites is critical to maintaining genetic diversity and maintaining metapopulation integrity. Despite this importance, records of long distances movements among wetlands are scarce in the literature, likely due to the lack of long-term studies for areas with multiple adjacent sites. In Virginia, mark recapture monitoring has been done intermittently in a cluster of sites for over 32 years. To determine the prevalence of movement among sites for bog turtles, I examined the dataset for all instances of turtles found at sites different from their last capture. I calculated the straight-line distance for each recorded movement. I also examined the sex of the turtle to test whether sex influences movement the frequency and distance of movements. For a subset of movements, I calculated least-cost pathways to identify possible barriers to movement using a previously published resistance model. I found 21 instances where a turtle was caught at a different site than its last capture over 32 years of monitoring. Neither sex was more likely to move farther than the other. Although the study's observed rate of movement may appear low, it is likely an underestimate when detection and asymmetric sampling are taken into account. The least cost pathways analysis suggested that roads or driveways were likely crossed for a significant portion of movement events. Finally, to examine how movement may be affecting the current distribution of bog turtles, I described a method to test whether adjacency to known populations influences the probability of a new site being occupied by turtles. I prove the utility of the method by applying it to a map of bog turtle occurrences collected over this study and show that it can account for habitat differences and barriers to movement between sites as well. In spite of plausibility of the method, limitations in how occurrence data are currently collected prevent its immediate application. Together, this thesis will help managers not only find and assess wetlands on the landscape, it will also provide information about the network of connected patches on the landscape. Knowing where bog turtles are and what wetlands or sub-populations are potentially connected will allowed for a more directed and informed regional management strategy.<br>Master of Science<br>Freshwater turtles are facing population declines worldwide, and the bog turtle Glyptemys muhlenbergii is among the most imperiled in North America. Bog turtles occupy naturally small, specialized wetlands called Appalachian Mountain fens. The prevalence of fens on the landscape has declined over recent decades due to agricultural practices. Although there is a strong need to document and monitor bog turtle populations due to their threatened status, bog turtles are difficult to find due to their small size and ability to burrow completely into substrate. Thus, considerable effort must be expended to find populations and track their status. The first overall objective of this thesis was to assess methods for locating populations of bog turtles. My first chapter tests a habitat distribution model that uses publicly available landscape data such as topopgraphy and land cover to predict areas likely to contain turtles. To do this, I systematically surveyed 49 predicted sites multiple times each over 2 years. Simultaneously, I recorded variables such as the time of year, size of the wetland and the weather to determine whether any factor significantly explained the ability to find turtles on any given survey. In addition, I was able to record several variables relating to wetland quality and isolation that were not in the initial model. I found that larger wetlands were easier to search than smaller wetlands, possibly due to larger sites having more turtles, and that wetlands near more impermeable surfaces (such as roads and buildings) were less likely to have bog turtles. As another potential method to find bog turtles and assess sites, we tested the use of 'pristine indicator' plants as a metric for potential wetlands. Mountain fens have specific attributes, such as high groundwater influence and exposure to a large amount of sunlight. Several species, including the bog turtle, are specialized to these factors and are rarely found in the surrounding landscape. Because a distinct community exists for mountain fens in this region, sites with a higher diversity of fen specialist plants may be indicative of a higher quality site which can support more specialists, including the bog turtle. My second chapter tests this hypothesis. I first chose a list of species that would most likely have habitat requirements similar to those of bog turtles. Then, at 12 sites I documented every plant species I encountered within the wetland. I compared the plant community as a whole between bog turtle-occupied and unoccupied sites and found no significant difference between the two. When I narrowed my analysis to focus on plants I previously identified as sharing habitat requirements with the bog turtle, I found a strong pattern of their co-occurrence with bog turtles. This lends support to the idea that these 'pristine indicator' plants could be used as a tool to better evaluate sites that may have bog turtles. My last chapter investigates movement of bog turtles in a landscape impacted by human development. Movement of turtles between adjacent wetlands is critical to maintaining long term regional viability of the species, as it lets turtles colonize new sites and exchange genes. Despite the importance of these movements, records of turtles moving long distances between two wetlands is scarce in the literature, likely due to the lack of long-term studies for areas with multiple adjacent wetlands. One method of recording movements is by marking turtles with a unique ID and recording where it was encountered as wetlands are surveyed on the landscape. In Virginia, this procedure has been conducted at multiple sites over 32 years. To understand the prevalence of movement between sites for this species, I examined this dataset and examined all instances of a turtle being found at a site different from its last capture. I recorded the straight-line distance moved for each recorded movement as well as the sex of the turtle, to test if either sex was more or less likely to undertake these movements. Then, for a subset of movements, I calculated least-cost pathways, a metric that accounts for landscape features and plots the easiest route for turtles to move. This way, I could evaluate the prevalence of barriers to movement, such as roads or development, on the landscape. I found 21 documented movements among sites over 32 years of monitoring. Neither sex was more likely to move further than the other. Compared to studies looking at other freshwater turtles, the observed rate of movement appeared low, but this was likely an underestimate due to the difficulty of capturing specific individuals. I also found evidence of significant barriers to movement in 13 out of 17 evaluated least-costs paths, usually roads or driveways. Finally, to examine how movement affects bog turtle distribution, I describe a methodology of testing if adjacency to known populations influences the probability of a new site being occupied by turtles. I demonstrate the plausibility of the method by applying it to a map of occurrences collected over this study and show that it can account for habitat differences and barriers to movement between sites as well. However, limitations in my sampling scheme limit conclusions from my dataset. Together, these findings will help future managers find where turtles are and which sites may be connected. These results will help managers make more informed decisions for managing bog turtles at a statewide level.

The aim of this thesis is to extend the understanding of early communication development through the design and implementation of methods, which enable close examination of developmental change as it happens. I pose that meaningful distinctions of infant’s attentional abilities, and preferences, in the early period of infancy are necessary and valuable for understanding the ontogeny of communication. Chapter 2 describes the First Steps longitudinal study, where the work of this thesis took place. Chapter 3 describes an adaptation to a coding scheme that allows for new advances in understanding of early infant’s attention abilities and preferences for social and non-social stimuli. Results show that by 2-months infants demonstrate group levels of engagement, as well as notable individual differences in time spent attending to mother’s faces and hand actions. Chapter 4 further demonstrates the value of the methodological adaptation described in Chapter 3, by assessing the predictive power individual differences shown in attention at 2-months hold for the emergence of social attention at 5-months. Results show that individual differences in infant attention to the social stimuli of faces and hands, demonstrated at 2 months with the adapted engagement coding scheme, differentially predict the social attention skills of attention following. Chapter 5 further extends the relations found in Chapter 4, by examining the relation between point following at the end of the first year and the proclivity to attend to hands, during interactions, at 18- months. Results show infants’ point following performance at 12-months predicts later durations of attention to hands, while playing with mothers at 18- months. In this thesis I argue that infant communication development cannot be understood from examining one domain, as infant’s employ multiple domains in the journey to communication. Secondly I argue that detailed observations following a multi-domain approach, offer significant potential for understanding communicative development. Chapter 6 details the design, application and assessment of the continuous unified electronic (CUE) diary method. Results show that the CUE diary method is reliable and valid method for the study of infant development. Chapter 7 utilizes the CUE diary method to examine whether the emergence of independent walking predicts later productive vocabulary. Results show that walking is a unique gross motor predictor of later vocabulary. Further, when entered into a predictive model for language, walking and pointing deliver independent predictive power, with walking demonstrating as strong an association as pointing. Taken together, these observational, experimental, parent-report and electronic diary methods demonstrate the advances in understanding communicative development that can be made when sensitive methods are applied across periods and domains of developmental change.

Education reform is shifting the landscape of New Orleans public schools, where alternative certification programs are thriving and changing the demographics of core teachers. This study follows a Teach for America (TFA) Corps Member from 2007 (just after the historic flooding from Hurricane Katrina) who brought a promise of innovation through idealism and green wisdom. The teacher’s preparation and motivations are shown to be problematic. Examining the assumptions and privileges that underlie the import of inexperienced talent to urban education systems, this study considers the ways that community voices have been lost or undervalued in New Orleans schools. The thesis tracks five unique student experiences in two schools over nine years, with accounts of the daily life of students and educators, some of whom are effective and make marked contributions to the community. The study concludes that care should be taken as reform continues to make schools better for kids.

Public health and social policies are often debated, designed, and adopted without implementation, sustainability, or equity in mind, which can generate profound uncertainty about how to equitably deliver them initially and over time. Although sustainability and equity considerations are sometimes considered in post-hoc policy analysis and evaluation, little is known about how to plan for and track planned and unplanned adaptations to policy implementation, as well as the ways that key sustainability factors and strategies can relate to the equitable delivery or relative effectiveness of policies on the ground and in community settings. The purpose of this dissertation was to explore the long-term sustainability and equity of tobacco control policies and programs in New York City to understand and contextualize their limited reach and impact on persistent smoking and tobacco-related health disparities in underserved Asian American communities. The specific aims were to: 1) conceptually specify an operational definition of policy sustainability and its key dimensions, including health equity, and to refine this using a mixed methods single case study of tobacco policies in New York City; 2) use the case study approach to describe the extent to which tobacco policies have been sustained and adapted in New York City; and 3) to use the case study to identify key multi-level factors that influence the long-term sustainability and equity of tobacco policies in New York City. Using a single, in-depth, convergent-parallel mixed methods case study design, data were collected, analyzed, and integrated across five key primary and secondary sources: 1) Policymaking documents – text of key tobacco bills and statutes, as well as transcripts from when they were first proposed, amended, debated, and adopted; 2) Local newspaper coverage – articles from a database of 29 major newspapers in New York State on the policies and their impacts on communities and businesses over time; 3) Key informant interviews – conducted with community members and community leaders at local health and advocacy organizations in New York City that primarily serve Asian American and immigrant communities (n = 21); 4) Direct observation periods – conducted within and around the health and advocacy organizations, as well as in majority Asian neighborhoods and Asian ethnic enclaves (n = 15); and 5) the New York City Community Health Survey (2012-2017) – conducted annually by the New York City Department of Health and Mental Hygiene. The integrated study findings point to the importance of understanding policy sustainability not as a static end goal, but rather as a dynamic set of processes and outcomes that impact health and health equity. Findings from this case study clustered across three key themes: 1) since the initial adoption of comprehensive local tobacco control measures in New York City in 2002, broad “one-size-fits-all” approaches to policy implementation and monitoring have been sustained, which have had and continue to have limited reach and impact within underserved Asian American and immigrant communities; 2) two delayed adaptation efforts were made by policymakers during the sustainability phase, one in 2012 and another in 2018, were intended to improve on prior uneven implementation to better reach Chinese-speaking communities, with the 2018 adaptation demonstrating significant improvements from the 2012 effort; and 3) community-based organizations have played a direct role in functioning not just as key stakeholders but also as key implementers to ensure that tobacco and other health policies are reaching communities that the designated or official implementers cannot reach. This suggests the need for further study of unofficial implementers in implementation science – those who have not been formally designated as the ones responsible for ensuring that implementation takes place, but are still delivering implementation strategies to ensure adoption, integration, and sustainment. Overall, this case study points to the potential for policy sustainability research to advance health equity by identifying factors and mechanisms that can be improved to maximize and sustain the equitable reach and impact of social and public health policies. By focusing on dynamic contextual factors and sustainability as a set of processes and outcomes, the findings from this case study raise critical questions about the criteria typically used to evaluate whether policy interventions are deemed evidence-based and effective by asking: 1) effective for whom?; 2) based on what evidence?; and 3) what happens as dynamic populations and contexts change over time? These questions highlight how the tobacco control success story was largely constructed around broad population-wide implementation and benefits, while overlooking underserved Asian American communities who continue to disproportionately bear the brunt of smoking and tobacco-related health disparities in New York City.

Indiana University-Purdue University Indianapolis (IUPUI)<br>The first part of the study describes the development of a microCT based engineering model to study orthodontic responses. The second part investigated the relationship between orthodontic stimulus, root resorption and bone modeling. It was hypothesized that stress magnitudes are insufficient to portray the mechanical environment and explain the clinical response; directions also play a role. An idealized tooth model was constructed for finite element analysis. The principal stress magnitudes and directions were calculated in tipping and translation. It was concluded that within the same region of root, PDL and bone, there can be compression in one structure, tension in another. At a given point in a structure, compression and tension can coexist in different directions. Magnitudes of compression or tension are typically different in different directions. Previously published data presenting only stress magnitude plots can be confusing, perhaps impossible to understand and/or correlate with biological responses. To avoid ambiguities, a reference to a principal stress should include its predominant direction. Combined stress magnitude/direction results suggest that the PDL is the initiator of mechanotransduction. The third part of this project tested the role of the P2X7 receptor in the dentoalveolar morphology of C57B/6 mice. P2X7R KO (knockout) mice were compared to C57B/6 WT to identify differences in a maxillary molar and bone. Tooth dimensions were measured and 3D bone morphometry was conducted. No statistically significant differences were found between the two mouse types. P2X7R does not have a major effect on alveolar bone or tooth morphology. The final part examines the role of the P2X7 receptor in a controlled biomechanical model. Orthodontic mechanotransduction was compared in wild-type (WT) and P2X7R knock-out (KO) mice. Using Finite Element Analysis, mouse mechanics were scaled to produce typical human stress levels. Relationships between the biological responses and the calculated stresses were statistically tested and compared. There were direct relationships between certain stress magnitudes and root resorption and bone formation. Hyalinization and root and bone resorption were different in WT and KO. Orthodontic responses are related to the principal stress patterns in the PDL and the P2X7 receptor plays a significant role in their mechanotransduction.