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3D soft tissue effects of rapid palatal expansionTorres, Diana M. 30 June 2019 (has links)
This retrospective cohort study investigated the effects of rapid maxillary expansion on the soft tissues using CBCTs. The sample consisted of 60 subjects: experimental group (n=30, treated with rapid maxillary expansion (RME), age:10.93 ± 2.20) and control group (n=30, age 11.43 ± 2.8). Soft tissue measurements were made using soft tissue landmarks. Paired t-test was used to compare the changes after expansion, and student t-test was used to compare the experimental and the control group. Intraclass correlation coefficient was used to evaluate intra-examiner reliability.
Statistically significant differences were noted when comparing the experimental to the control group in transverse and anterior posterior dimensions. Increase was noted at the bialar distance (0.90mm, p=0.0363), nostril medium left to midsagittal plane (0.75mm, p=0.0423), the angle of pronasale to nostril base right and left (1.640, p<.001), columella width (0.56mm, p=0.0272), nostril base left to midsagittal plane, (1.03mm, p=0.0207), chelion right to endocanthus right (1.57mm, p=0.0086), chelion left to endocanthus left (1.96mm, p=0.0015). Anteroposteriorly, the tip of the nose moved forward (pronasale to coronal plane (1.97mm, p=0.0018), nostril medium right to coronal plane (1.07mm, p=0.0486), alare right to coronal plane (1.67mm, p=0.0117), pronasale to nostril base left (2.24mm, p<0.001) and right (2.12mm, p<0.001).
Finally comparing genders, all the measurements were significantly greater in males compared to females except for columella width.
In conclusion, RME influences soft tissue changes of the face, specifically in the nasal area. The base of the nose, bialar distance and columella widened while the tip of the nose moved forward.
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Effects of PYK2-Deficiency on Midpalatal Suture Expansion in MiceSun, Jun 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Background: Suture expansion is a very important clinical approach to correct maxillary width deficiency, but it has a high potential for treatment relapse. Accelerating bone formation and mineralization in the midpalatal suture during suture expansion is beneficial in preventing relapse of the arch width and reducing the retention period. Pyk2 is tyrosine kinase which has been shown to mediate signaling pathways that are involved in the process of bone remodeling. Pyk2 knock-out (KO) mice have augmented bone formation and increased bone mass, suggesting that therapeutic strategies that inhibit Pyk2 may be useful to enhance bone remodeling and prevent suture relapse during suture expansion.
Objectives: To determine if Pyk2-deficiency affects midpalatal suture bone mass and bone remodeling with or without suture expansion in mice.
Methods: Thirty-six Pyk2-KO and thirty-six wild type (WT) 6 week-old male mice were randomly assigned into three groups: receiving no expansion force (0 g), 10 g or 20 g force of rapid maxillary expansion for 14 days. Half of the mice in each group were used for histology analysis; the other half was assigned for fluorescence analysis. Suture width, maxilla width and bone volume/tissue volume around suture bone edges were measured using micro-CT. Histological analyses of osteoclasts (tartrate resistant acid phosphatase, TRAP), osteoblasts (alkaline phosphatase, ALP) and chondrocytes (alcian blue) were performed.
Results: The BV/TV ratio was significantly higher in Pyk2-KO control mice compared to WT control mice. Suture expansion in WT and Pyk2-KO mice led to an increase in bone marrow spaces around the suture edge and significantly reduced BV/TV. Expansion also led to a significant increase in suture width, suture fibrous area, osteoclast number, cartilage area and hypertrophic chondrocyte number. However, BV/TV in Pyk2-KO mice was significantly higher than in WT mice at both the 10 g and 20 g force levels. In addition, Pyk2-KO exhibited reduced suture width, maxilla width, fibrous area and osteoclast number per bone surface (OC.S/BS) compared to WT mice under expansion forces. Cartilage area and hypertrophic chondrocyte number were increased by force but were independent of mouse genotypes.
Conclusion: Pyk2-KO mice have higher BV/TV and narrower suture width compared to WT mice, which may be due to decreased osteoclast activity. The higher BV/TV of the midpalatal sutures of Pyk2-KO mice following suture expansion may suggest the presence of a more stable suture that has a reduced potential for relapse. Therapeutic strategies to inhibit Pyk2 during RME may be beneficial in increasing bone mass and preventing relapse of the suture.
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Effects of vibration forces on maxillary expansion and orthodontic tooth movementAldosari, Mohammad Abdullah M. January 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Vibration forces (VF) have been shown to alter the formative and resorptive activities of bone. Studies have investigated the use of VF in applications such as the treatment of osteoporosis, bone fracture healing and implant osteointegration with favorable results. In dentistry, orthodontic tooth movement and maxillary suture expansion are common procedures typically requiring prolonged treatment durations with high relapse rates. We hypothesized that local, intermittent VF applications can enhance bone formation during rapid maxillary expansion and accelerate orthodontic tooth movement. Moreover, we also investigated expression of periostin/OSF-2, an adhesion molecule implicated in the formation of bone during maxillary suture expansion. Our results showed that intermittent VF significantly increased bone volume density of the expended palatal bone but limited the amount of palatal expansion and mineral apposition rate at the suture margins. Also, intermittent VF forces did not show statistically significant acceleration of orthodontic tooth movement but significantly enhanced bone volume density of the interradicular bone after tooth movement. Maxillary expansion was also shown to induce the expression of periostin which was proportional to the magnitude of the expansion force with increased bone mineral deposition.
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Development, application, and expansion of VADER, a platform for directed evolution in mammalian cells:Jewel, Delilah January 2023 (has links)
Thesis advisor: Abhishek Chatterjee / Thesis advisor: Eranthie Weerapana / In nature, just twenty canonical amino acids are responsible for the creation of nearly all proteins. Genetic code expansion (GCE), or the incorporation of noncanonical amino acids (ncAAs) into living cells, is a powerful tool that expands the studies we are capable of performing using proteins. This technology relies on engineered aminoacyl-tRNA synthetase (aaRS)/tRNA pairs that are orthogonal to the host cells’ endogenous aaRS/tRNA pairs, and one of the main limitations of GCE arises from the inefficiency of these suppressor tRNAs when expressed in a foreign host cell. To address this limitation, we have previously reported a strategy for the virus-assisted directed evolution of tRNAs (VADER) which is uniquely capable of addressing the specific needs of tRNA evolution. In order to advance the capabilities of VADER, we made a number of modifications to the VADER selection scheme. First, we designed and executed a modified VADER selection that enabled the evolution of a new class of tRNAs, and with this VADER selection, we were able to generate a first-generation E. coli tyrosyl tRNA (tRNATyr) variant that was three times as active as its wild-type equivalent. Next, we introduced a number of refinements to the VADER strategy to generate VADER 2.0, an improved workflow capable of screening larger libraries and libraries encoding more active variants. Using VADER 2.0, we created second-generation tRNAPyl and tRNATyr mutants that achieved incorporation efficiencies that were greater than five-fold higher than their wild-type equivalents across a wide variety of substrates, enabling exciting GCE experiments that would not be possible otherwise. / Thesis (PhD) — Boston College, 2023. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
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An Overview of the Current Alternative Dispute Resolution (ADR) System: Projections for Future Expansion of ADR within Florida's Civil Court SystemPatterson, Alysia Rose 01 January 2023 (has links) (PDF)
Currently, mediation in Florida is a pre-suit requirement only for condo associations, homeowner disputes, and medical malpractice suits, as discussed in Florida Statute Chapter 720.311, 718.1255, 766.108, as well as those ordered by a judge. The American Bar Association (ABA) also reported that only 23 of the 204 law schools (11%) approved by the ABA require some form of Alternative Dispute Resolution (ADR) coursework to graduate. Changes need to be made for the ADR program to thrive and reach its full potential within our judicial system. This thesis will highlight that by calling for the government to make mediation a pre-suit requirement for other suitable areas in the civil court system. This thesis will also address the need for more law schools to require ADR training within their curriculum to create a new generation who understands and has the skills to implement ADR into their future law practices. By examining successful trends in ADR, statutes, and programs that have encouraged or forced the use of ADR, this thesis will provide ways ADR can reach its full potential within our court system. This thesis will contribute to the field of law, specifically in terms of contributing to the lack of data on ADR programs that reflect their positive impacts and where they might be most beneficial.
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Increasing the computational efficiency of ab initio methods with generalized many-body expansionsRichard, Ryan January 2013 (has links)
No description available.
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Simulating Future Land Use Change in the East Fork Little Miami River (EFLMR) Watershed in OhioSun, Yu 20 April 2009 (has links)
No description available.
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Asymptotic expansion for the <i>L</i><sup>1</sup> Norm of N-Fold convolutionsStey, George C. 27 March 2007 (has links)
No description available.
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Evaluating shrub expansion in a subarctic mountain basin using multi-temporal LiDAR dataLeipe, Sean January 2020 (has links)
High-latitude ecosystems have experienced substantial warming over the past 40 years, which is expected to continue into the foreseeable future. Consequently, an increase in vegetation growth has occurred throughout the circumpolar North as documented through remote sensing and plot-level studies. A major component of this change is shrub expansion (shrubbing) in arctic and subarctic ecotones. However, these changes are highly variable depending on plant species, topographic position, hydrology, soils and other ecosystem properties. Changes in shrub and other vegetation properties are critical to document due to their first-order control on water, energy and carbon balances. This study uses a combination of multi-temporal LiDAR (Light Detection and Ranging) and field surveys to measure temporal changes in shrub vegetation cover over the Wolf Creek Research Basin (WCRB), a 180 km2 long-term watershed research facility located ~15 km south of Whitehorse, Yukon Territory. This work focuses on the smaller Granger Basin, a 7.6 km2 subarctic headwater catchment that straddles WCRB’s subalpine and alpine tundra ecozones with a wide range of elevation, landscape topography, and vegetation. Airborne LiDAR surveys of WCRB were conducted in August 2007 and 2018, providing an ideal opportunity to explore vegetation changes between survey years. Vegetation surveys were conducted throughout Granger Basin in summer 2019 to evaluate shrub properties for comparisons to the LiDAR. Machine learning classification algorithms were used to predict shrub presence/absence in 2018 based on rasterized LiDAR metrics with up to 97% overall independent accuracy compared to field validation points, with the best-performing model applied to the 2007 LiDAR to create binary shrub cover layers to compare between survey years. Results show a 63.3% total increase in detectable shrub cover > 0.45 m in height throughout Granger Basin between 2007 and 2018, with an average yearly expansion of 5.8%. These changes in detectable shrub cover were compared across terrain derivatives created using the LiDAR to quantify the influence of topography on shrub expansion. The terrain comparison results show that shrubs in the study area are located in and are preferentially expanding into lower and flatter areas near stream networks, at lower slope positions and with a higher potential for topographic wetness. The greatest differences in terrain derivative value distributions across the shrub and non-shrub change categories were found in terms of stream distance, elevation, and relative slope position. This expansion of shrubs into higher-resource areas is consistent with previous studies and is supported by established physical processes. As vegetation responses to warming have far-reaching influences on surface energy exchange, nutrient cycling, and the overall water balance, this increase in detectable shrub cover has a wide range of impacts on the future of northern watersheds. Overall, the findings from this research reinforce the documented increase in pan-Arctic shrub vegetation in recent years, quantify the variation in shrub expansion over terrain derivatives at the landscape scale, and demonstrate the feasibility of using LiDAR to compare changes in shrub properties over time. / Thesis / Master of Science (MSc)
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Stabilité de l'expansion palatine assistée chirurgicalement comparée à une ostéotomie Le Fort 1 multisegmentéeChamberland, Sylvain 13 April 2018 (has links)
Ce projet visait à comparer deux traitements chirurgicaux d'expansion palatine pour la correction des déficits transverses des maxillaires. Dans une étude prospective, les données de 22 sujets ayant terminé leur traitement orthodontique et ayant eu une expansion palatine assistée chirurgicalement (EPRAC) sont comparées à un groupe contrôle historique traité avec une ostéotomie Le Fort 1. L'expansion et la récidive dentaire et squelettique obtenue avec l'EPRAC ainsi que la récidive ont été mesurées sur des modèles d'étude et des radiographies céphalométriques postéro-antérieures standardisées à cinq moments durant le traitement. Dans le groupe EPRAC, l'expansion dentaire moyenne est 7,48 ± 1,39 mm. La récidive est 2,22 ± 1,69 mm (30%). À la fin de la distraction osseuse, 3,49 ± 1,37 mm d'expansion squelettique ont été obtenus. Lors d'une EPRAC, il faut anticiper la perte du tiers de l'expansion dentaire alors que l'expansion squelettique est stable. La récidive postchirurgicale de l'EPRAC semble similaire aux changements de l'arcade dentaire après une expansion à l'aide d'une ostéotomie maxillaire segmentée (3,06 ±1,31 mm)
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