386 research outputs found
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Deck the Halls
This paper won a second place writing flag award in the creative/reflective category. Madeline Buschang. writing for Matthew Valentine's T C 358 class, "Writing Narratives".Valentine, MatthewUndergraduate Studie
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The Power of Rhetoric: A Case Study of the German Generals of WWII
During World War II, Hitler employed a lot of tactical rhetoric and the use of this rhetoric is often noted as being extraordinarily persuasive, but I wanted to know if there is rhetorical evidence to suggest that this was the case. In order to do this, I looked at five of Hitler’s most prominent rhetorical topoi and examined the end-of-war/post-war rhetoric of German generals in both private and public settings for evidence of the repetition of these topoi in their deliberations.
By looking at this rhetorical evidence more closely it became clear that the answer to whether Hitler was truly persuasive was maybe. The topoi that are found in the rhetoric of both the public and private generals and in Hitler are those with a basis in the German culture, thus while this repetition of topoi may be a result of Hitler’s rhetorical power, it is also possible that this power was overstated and that what looks like persuasion is rather the weaponization of these beliefs by Hitler.Plan II Honors Progra
Orthopedic Correction of Growing Hyperdivergent, Retrognathic Patients With Miniscrew Implants
Traditional orthodontic treatments do not adequately address the skeletal problems of retrognathic, hyperdivergent, Class II adolescents; the few approaches that do require long-term patient compliance. This paper introduces a novel approach using miniscrew implants (MSIa) and growth to treat retrognathic hyperdivergent adolescents. Nine consecutive patients were evaluated at the start of treatment (13.2 ±1.1 years of age) and again at the end of the orthopedic phase (after 1.9 ±0.3 years). Each patient had two MSIs placed in either side of the palate. Coil springs (150 g) extended from the MSIs to a RPE, which served as a rigid segment for intruding the maxillary premolar and molars. Two additional MSIs were placed between the first mandibular molars and second premolars; coil spring (150 g) extended from the MSIs to hold or intrude the mandibular molars. Prior to treatment, the patients exhibited substantial and significant mandibular retrusion (Z-score=−1.0), facial convexity (Z-score=0.7), and hyperdivergence (Z-score=1.6). Treatment produced consistent and substantial orthopedic effects. The chin was advanced an average of 2.4 mm, the SNB angle increased by 2.1°, the mandibular plane angle decreased 3.9°, and facial convexity decreased by approximately 3.2°. Questionnaires showed that this treatment approach was not painful or uncomfortable; the majority of the patients indicated that they were very likely to recommend the treatment to others. Treatment was accomplished by titrating the amount of orthodontic intrusion performed based on the individuals’ growth potential
Progress in operational modeling in support of oil spill response
Following the 2010 Deepwater Horizon accident of a massive blow-out in the Gulf of Mexico, scientists from government, industry, and academia collaborated to advance oil spill modeling and share best practices in model algorithms, parameterizations, and application protocols. This synergy was greatly enhanced by research funded under the Gulf of Mexico Research Initiative (GoMRI), a 10-year enterprise that allowed unprecedented collection of observations and data products, novel experiments, and international collaborations that focused on the Gulf of Mexico, but resulted in the generation of scientific findings and tools of broader value. Operational oil spill modeling greatly benefited from research during the GoMRI decade. This paper provides a comprehensive synthesis of the related scientific advances, remaining challenges, and future outlook. Two main modeling components are discussed: Ocean circulation and oil spill models, to provide details on all attributes that contribute to the success and limitations of the integrated oil spill forecasts. These forecasts are discussed in tandem with uncertainty factors and methods to mitigate them. The paper focuses on operational aspects of oil spill modeling and forecasting, including examples of international operational center practices, observational needs, communication protocols, and promising new methodologies
Skeletal growth in class II malocclusion from childhood to adolescence: does the profile straighten?
BACKGROUND
There is relatively little appreciation of the changes in maxillary-mandibular relationships occurring during adolescence among subjects with normal and increased overjet. The aim of this study was to assess differences in changes in maxillo-mandibular relationships during the adolescent growth period based on the presence of a normal ( 4 mm) overjet in childhood. Our hypothesis was that there is no difference in the change of the A point, nasion, B point (ANB) angle during growth between these two overjet groups. Lateral cephalograms were obtained from 65 subjects taken from the American Association of Orthodontists Foundation (AAOF) Craniofacial Growth Legacy Collections Project. Cephalograms were obtained at ages 7-10 (T0) and 14-17 (T1) with allocation into two groups based on baseline overjet (> 4 mm: group 1, 2-4 mm: group 2). Random effects linear regression was used to account for multiple within -patient measurements with dependent variables including antero-posterior skeletal pattern (based on sella, nasion, A point (SNA); sella, nasion, B point (SNB); and ANB angles).
RESULTS
We included a similar number of males (n = 34; 52.3%) and females (n = 31; 47.7%). The mean ANB was higher at baseline in group 1 (5.42, SD 2.16°) than in group 2 (3.08, SD 1.91°). The hypothesis was rejected as the ANB angle reduced by 1.92° more in the larger overjet group with the association being statistically significant after accounting for age and gender (P  4 mm overjet group compared to the 2-4 mm group (0.857°, P = 0.271; 95% CI - 0.669 to 2.383). The SNB angle increased by 1.15° more in the higher overjet group but there was only weak evidence of an association (P = 0.086; 95% CI - 2.464 to 0.164).
CONCLUSIONS
A slight straightening of the facial profile was observed in both groups with a statistically significant greater reduction in ANB arising in the group with larger baseline overjet. This translated into a marginal reduction in the overjet in this group
Mesh management methods in finite element simulations of orthodontic tooth movement
In finite element simulations of orthodontic tooth movement, one of the challenges is to represent long term tooth movement. Large deformation of the periodontal ligament and large tooth displacement due to bone remodelling lead to large distortions of the finite element mesh when a Lagrangian formalism is used. We propose in this work to use an Arbitrary Lagrangian Eulerian (ALE) formalism to delay remeshing operations. A large tooth displacement is obtained including effect of remodelling without the need of remeshing steps but keeping a good-quality mesh. Very large deformations in soft tissues such as the periodontal ligament is obtained using a combination of the ALE formalism used continuously and a remeshing algorithm used when needed. This work demonstrates that the ALE formalism is a very efficient way to delay remeshing operations
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Effect of mastication on lipid bioaccessibility of almonds in a randomized human study and its implications for digestion kinetics, metabolizable energy, and postprandial lipemia
Background: The particle size and structure of masticated almonds impact significantly on nutrient release (bioaccessibility) and digestion kinetics.
Objectives: To quantify the effects of mastication on the bioaccessibility of intracellular lipid of almond tissue and examine microstructural characteristics of masticated almonds.
Design: In a randomized, subject-blind, crossover trial, 17 healthy subjects chewed natural (NA) or roasted almonds (RA) on 4 separate mastication sessions. Particle size distributions (PSDs) of the expectorated boluses were measured using mechanical sieving and laser diffraction (primary outcome). The microstructure of masticated almonds, including the structural integrity of the cell walls (i.e. dietary fiber), was examined using microscopy. Lipid bioaccessibility was predicted using a theoretical model, based on almond particle size and cell dimensions, and then compared to empirically-derived release data.
Results: Inter-subject variations (n=15, 2 subjects withdrew) in PSDs of both NA and RA samples were small (e.g. laser diffraction, CV = 12% and 9%, respectively). Significant differences in PSDs were found between these two almond forms (P 500 µm) in masticated almonds. Microstructural examination of the almonds indicated that most intracellular lipid remained undisturbed in intact cells post-mastication. No adverse events were recorded.
Conclusions: Following mastication, most of the almond cells remained intact with lipid encapsulated by cell walls. Thus, most of the lipid (>88%) in masticated almonds is not immediately bioaccessible and remains unavailable for digestion and absorption. The lipid encapsulation mechanism provides a convincing explanation for why almonds have a low metabolizable energy content and an attenuated impact on postprandial lipemia. Trial registration number; ISRCTN58438021
The not-so-Dark Ages: Ecology for human growth in medieval and early Twentieth Century Portugal as inferred from skeletal growth profiles
This study attempts to address the issue of relative living standards in Portuguese medieval and early 20th century periods. Since the growth of children provides a good measure of environmental quality for the overall population, the skeletal growth profiles of medieval Leiria and early 20th century Lisbon were compared. Results show that growth in femur length of medieval children did not differ significantly from that of early 20th century children, but after puberty medieval adolescents seem to have recovered, as they have significantly longer femora as adults. This is suggestive of greater potential for catch-up growth in medieval adolescents. We suggest that this results from distinct child labor practices, which impact differentially on the growth of Leiria and Lisbon adolescents. Work for medieval children and adolescents were related to family activities, and care and attention were provided by family members. Conversely, in early 20th century Lisbon children were more often sent to factories at around 12 years of age as an extra source of family income, where they were exploited for their labor. Since medieval and early 20th century children were stunted at an early age, greater potential for catch-up growth in medieval adolescents results from exhausting work being added to modern adolescent's burdens of disease and poor diet, when they entered the labor market. Although early 20th century Lisbon did not differ in overall unfavorable living conditions from medieval Leiria, after puberty different child labor practices may have placed modern adolescents at greater risk of undernutrition and poor growth. Am J Phys Anthropol, 2008. © 2008 Wiley-Liss, Inc
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