A survey of undergraduate orthodontic teaching and factors affecting pursuit of postgraduate training

Background: Undergraduate orthodontic teaching has been focused on developing an understanding of occlusal development in an effort to equip practitioners to make appropriate referrals for specialist-delivered care. However, there is a growing interest among general dentists in delivering more specialised treatments, including short-term orthodontic alignment. This study aimed to assess the levels of knowledge of occlusal problems among final year undergraduate dental students, as well as their interest in various orthodontics techniques and training.Methods: A 36-item electronic questionnaire was sent to all final year undergraduate students in four dental institutes in the UK (Barts and the London, Kings College London, Cardiff and Dundee). The questionnaire explored satisfaction with undergraduate orthodontic teaching; students’ perception of knowledge, based on General Dental Council learning outcomes; perceptions of the need for specialist involvement in the management of dental problems; interest in further training in orthodontics; and potential barriers to undertaking specialist training.Results: The overall response rate was 66% (239/362). The majority of students (84.1%) were aware of GDC guidance in terms of undergraduate teaching. Students reported a preference for case-based and practical teaching sessions in orthodontics, with less interest in lectures or problem-based learning approaches. A high percentage were interested in further teaching in interceptive orthodontics (60.3%) and fixed appliance therapy (55.7%). Further training including specialist orthodontic training (36.4%), Invisalign (59%) and Six Month Smiles (41%) courses appealed to undergraduates. Levels of student debt, course fees and geographical issues were seen as potential barriers to formal, specialist training pathways.Conclusions: Satisfaction with undergraduate orthodontic teaching is high and interest in further training, including specialist training pathways, continues to be high. While short-term orthodontics is not taught at undergraduate level, there appears to be an appetite to undertake alternatives to conventional orthodontics among dental students

Search for sterile neutrino mixing in the MINOS long-baseline experiment

A search for depletion of the combined flux of active neutrino species over a 735 km baseline is reported using neutral-current interaction data recorded by the MINOS detectors in the NuMI neutrino beam. Such a depletion is not expected according to conventional interpretations of neutrino oscillation data involving the three known neutrino flavors. A depletion would be a signature of oscillations or decay to postulated noninteracting sterile neutrinos, scenarios not ruled out by existing data. From an exposure of 3.18×1020 protons on target in which neutrinos of energies between ~500¿¿MeV and 120 GeV are produced predominantly as ¿µ, the visible energy spectrum of candidate neutral-current reactions in the MINOS far detector is reconstructed. Comparison of this spectrum to that inferred from a similarly selected near-detector sample shows that of the portion of the ¿µ flux observed to disappear in charged-current interaction data, the fraction that could be converting to a sterile state is less than 52% at 90% confidence level (C.L.). The hypothesis that active neutrinos mix with a single sterile neutrino via oscillations is tested by fitting the data to various models. In the particular four-neutrino models considered, the mixing angles ¿24 and ¿34 are constrained to be less than 11° and 56° at 90% C.L., respectively. The possibility that active neutrinos may decay to sterile neutrinos is also investigated. Pure neutrino decay without oscillations is ruled out at 5.4 standard deviations. For the scenario in which active neutrinos decay into sterile states concurrently with neutrino oscillations, a lower limit is established for the neutrino decay lifetime t3/m3>2.1×10-12¿¿s/eV at 90% C.L

Systems and technologies for objective evaluation of technical skills in laparoscopic surgery

Minimally invasive surgery is a highly demanding surgical approach regarding technical requirements for the surgeon, who must be trained in order to perform a safe surgical intervention. Traditional surgical education in minimally invasive surgery is commonly based on subjective criteria to quantify and evaluate surgical abilities, which could be potentially unsafe for the patient. Authors, surgeons and associations are increasingly demanding the development of more objective assessment tools that can accredit surgeons as technically competent. This paper describes the state of the art in objective assessment methods of surgical skills. It gives an overview on assessment systems based on structured checklists and rating scales, surgical simulators, and instrument motion analysis. As a future work, an objective and automatic assessment method of surgical skills should be standardized as a means towards proficiency-based curricula for training in laparoscopic surgery and its certification

Measuring and Comparing Party Ideology and Heterogeneity

Estimates of party ideological positions in Western Democracies yield useful party-level information, but lack the ability to provide insight into intraparty politics. In this paper, we generate comparable measures of latent individual policy positions from elite survey data which enable analysis of elite-level party ideology and heterogeneity. This approach has advantages over both expert surveys and approaches based on behavioral data, such as roll call voting and is directly relevant to the study of party cohesion. We generate a measure of elite positions for several European countries using a common space scaling approach and demonstrate its validity as a measure of party ideology. We then apply these data to determine the sources of party heterogeneity, focusing on the role of intraparty competition in electoral systems, nomination rules, and party goals. We find that policy-seeking parties and centralized party nomination rules reduce party heterogeneity. While intraparty competition has no effect, the presence of these electoral rules conditions the effect of district magnitude

Probabilistic downscaling of remote sensing data with applications for multi-scale biogeochemical flux modeling

Upscaling ecological information to larger scales in space and downscaling remote sensing observations or model simulations to finer scales remain grand challenges in Earth system science. Downscaling often involves inferring subgrid information from coarse-scale data, and such ill-posed problems are classically addressed using regularization. Here, we apply two-dimensional Tikhonov Regularization (2DTR) to simulate subgrid surface patterns for ecological applications. Specifically, we test the ability of 2DTR to simulate the spatial statistics of high-resolution (4 m) remote sensing observations of the normalized difference vegetation index (NDVI) in a tundra landscape. We find that the 2DTR approach as applied here can capture the major mode of spatial variability of the high-resolution information, but not multiple modes of spatial variability, and that the Lagrange multiplier (γ) used to impose the condition of smoothness across space is related to the range of the experimental semivariogram. We used observed and 2DTR-simulated maps of NDVI to estimate landscape-level leaf area index (LAI) and gross primary productivity (GPP). NDVI maps simulated using a γ value that approximates the range of observed NDVI result in a landscape-level GPP estimate that differs by ca 2% from those created using observed NDVI. Following findings that GPP per unit LAI is lower near vegetation patch edges, we simulated vegetation patch edges using multiple approaches and found that simulated GPP declined by up to 12% as a result. 2DTR can generate random landscapes rapidly and can be applied to disaggregate ecological information and compare of spatial observations against simulated landscapes

Measurement of single π0 production by coherent neutral-current ν Fe interactions in the MINOS Near Detector

Forward single π0 production by coherent neutral-current interactions, νA→νAπ0, is investigated using a 2.8×1020 protons-on-target exposure of the MINOS Near Detector. For single-shower topologies, the event distribution in production angle exhibits a clear excess above the estimated background at very forward angles for visible energy in the range 1-8 GeV. Cross sections are obtained for the detector medium comprised of 80% iron and 20% carbon nuclei with =48, the highest- target used to date in the study of this coherent reaction. The total cross section for coherent neutral-current single π0 production initiated by the νμ flux of the NuMI low-energy beam with mean (mode) Eν of 4.9 GeV (3.0 GeV), is 77.6±5.0(stat)-16.8+15.0(syst)×10-40 cm2 pernucleus. The results are in good agreement with predictions of the Berger-Sehgal model

Allergic conditions and risk of hematological malignancies in adults: a cohort study

BACKGROUND: Two contradictory hypotheses have been proposed to explain the relationship between allergic conditions and malignancies, the immune surveillance hypothesis and the antigenic stimulation hypothesis. The former advocates that allergic conditions may be protective against development of cancer, whereas the latter proposes an increased risk. This relationship has been studied in several case-control studies, but only in a few cohort studies. METHODS: The association between allergic conditions and risk of developing leukemia, Hodgkin's disease, non-Hodgkin's lymphoma and myeloma was investigated in a cohort of 16,539 Swedish twins born 1886–1925. Prospectively collected, self-reported information about allergic conditions such as asthma, hay fever or eczema was obtained through questionnaires administered in 1967. The cohort was followed 1969–99 and cancer incidence was ascertained from the Swedish Cancer Registry. RESULTS: Hives and asthma tended to increase the risk of leukemia (relative risk [RR] = 2.1, 95% Confidence Interval [CI] 1.0–4.5 and RR = 1.6, 95% CI 0.8–3.5, respectively). There was also an indication of an increased risk of non-Hodgkin's lymphoma associated with eczema during childhood (RR = 2.3, 95% CI 1.0–5.3). CONCLUSION: In contrast to most previous studies, our results do not indicate a protective effect of allergic conditions on the risk of developing hematological malignancies. Rather, they suggest that allergic conditions might increase the risk of some hematological malignancies

Cross-Platform Comparison of Microarray-Based Multiple-Class Prediction

High-throughput microarray technology has been widely applied in biological and medical decision-making research during the past decade. However, the diversity of platforms has made it a challenge to re-use and/or integrate datasets generated in different experiments or labs for constructing array-based diagnostic models. Using large toxicogenomics datasets generated using both Affymetrix and Agilent microarray platforms, we carried out a benchmark evaluation of cross-platform consistency in multiple-class prediction using three widely-used machine learning algorithms. After an initial assessment of model performance on different platforms, we evaluated whether predictive signature features selected in one platform could be directly used to train a model in the other platform and whether predictive models trained using data from one platform could predict datasets profiled using the other platform with comparable performance. Our results established that it is possible to successfully apply multiple-class prediction models across different commercial microarray platforms, offering a number of important benefits such as accelerating the possible translation of biomarkers identified with microarrays to clinically-validated assays. However, this investigation focuses on a technical platform comparison and is actually only the beginning of exploring cross-platform consistency. Further studies are needed to confirm the feasibility of microarray-based cross-platform prediction, especially using independent datasets

Evaluating Psychometric Properties of an Instrument Addressing Comprehensiveness of Care Among Dentists

Universidade Federal de Minas Gerais. Departamento de Odontologia Comunitária e Preventiva. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Instituto René Rachou. Belo Horizonte, MG, Brazil.Division of Population and Patient Health. King’s College London Dental Institute at Guy’s. King’s College and St Thomas’ Hospitals. London, UK.Universidade Federal de Minas Gerais. Departamento de Ortodontia e Odontopediatria Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Departamento de Odontologia Comunitária e Preventiva. Belo Horizonte, MG, Brazil.Objetivou-se avaliar as propriedades psicométricas de um instrumento para avaliar a integralidade do cuidado por dentistas, usando uma combinação da teoria clássica e teoria da resposta ao item. Um instrumento com 46 itens foi desenvolvido e testado por um painel de experts, seguido por um teste piloto e aplicação em 187 dentistas da atenção primária de uma grande cidade brasileira. Os seguintes critérios foram utilizados para avaliar os 46 itens: aceitabilidade, consistência interna, estabilidade temporal, correlação inter-item e correlação tetracórica. Essa avaliação resultou em uma versão reduzida de 11 itens que preencheram todos os critérios descritos acima. A estabilidade temporal foi medida utilizando o Cohen Kappa. Os 11 itens apresentaram valores maiores que 0,5. O alfa de Cronbach foi de 0,72. Nenhum dos 11 itens apresentou perda na distribuição das respostas, e o modelo que considera a discriminação como variante se adequa melhor aos dados do que o modelo que considera a discriminação como um parâmetro constante (p <0,001). Curvas características mostraram que 54,5% dos itens pode ser considerado difícil, ou seja, apenas os dentistas com uma boa compreensão da integralidade respondeu favoravelmente. O instrumento de 11 itens para avaliar a integralidade do cuidado por dentistas é considerado como tendo boas propriedades psicométricas.This study aimed to evaluate the psychometric properties of an instrument to assess comprehensiveness of care from dentists using a combination of classical test theory and item response theory. A 46-item instrument was developed and tested by a panel of experts, followed by a pilot test and administration to 187 primary care dentists in a large Brazilian city. The 46 items were evaluated using the following criteria: acceptability, internal consistency, temporal stability, inter-item correlation, and tetrachoric correlation. This evaluation led to a shortened version consisting of 11 items that met all the criteria previously described. The temporal stability was measured using Cohen’s kappa, and all 11 items presented values greater than 0.5. The Cronbach’s alpha value was 0.72. None of the 11 items had missing data on the distribution of responses, and the model considering the discrimination as varying fit the data better than the model considering discrimination as a constant parameter (p<0.001). Item characteristic curves showed that 54.5% of items could be considered difficult, i.e., only dentists with a good understanding of comprehensiveness responded favorably. The 11-item instrument to assess comprehensiveness of care by dentists is considered to have good psychometric properties