88 research outputs found
How deep is your lab? Understanding the possibilities and limitations of living labs in tourism.
Vibrations of a Columnar Vortex in a Trapped Bose-Einstein Condensate
We derive a governing equation for a Kelvin wave supported on a vortex line
in a Bose-Einstein condensate, in a rotating cylindrically symmetric parabolic
trap. From this solution the Kelvin wave dispersion relation is determined. In
the limit of an oblate trap and in the absence of longitudinal trapping our
results are consistent with previous work. We show that the derived Kelvin wave
dispersion in the general case is in quantitative agreement with numerical
calculations of the Bogoliubov spectrum and offer a significant improvement
upon previous analytical work.Comment: 5 pages with 1 figur
The WARPS Survey. VIII. Evolution of the Galaxy Cluster X-ray Luminosity Function
We present measurements of the galaxy cluster X-ray Luminosity Function (XLF)
from the Wide Angle ROSAT Pointed Survey (WARPS) and quantify its evolution.
WARPS is a serendipitous survey of the central region of ROSAT pointed
observations and was carried out in two phases (WARPS-I and WARPS-II). The
results here are based on a final sample of 124 clusters, complete above a flux
limit of 6.5 10E-15 erg/s/cm2, with members out to redshift z ~ 1.05, and a sky
coverage of 70.9 deg2. We find significant evidence for negative evolution of
the XLF, which complements the majority of X-ray cluster surveys. To quantify
the suggested evolution, we perform a maximum likelihood analysis and conclude
that the evolution is driven by a decreasing number density of high luminosity
clusters with redshift, while the bulk of the cluster population remains nearly
unchanged out to redshift z ~ 1.1, as expected in a low density Universe. The
results are found to be insensitive to a variety of sources of systematic
uncertainty that affect the measurement of the XLF and determination of the
survey selection function. We perform a Bayesian analysis of the XLF to fully
account for uncertainties in the local XLF on the measured evolution, and find
that the detected evolution remains significant at the 95% level. We observe a
significant excess of clusters in the WARPS at 0.1 < z < 0.3 and LX ~ 2 10E42
erg/s compared with the reference low-redshift XLF, or our Bayesian fit to the
WARPS data. We find that the excess cannot be explained by sample variance, or
Eddington bias, and is unlikely to be due to problems with the survey selection
function.Comment: 13 pages, 12 figures, accepted for publication in MNRA
Is small beautiful? Understanding the contribution of small businesses in township tourism to economic development
The increased importance attached by policy-makers to the anticipated developmental effects of tourism in developing countries has been insufficiently examined by academic researchers, particularly in the context of the contribution of small firms in urban areas. This deficiency is addressed by providing a review of existing research followed by an analysis of interviews with 90 tourism business located within and outside the townships of Langa and Imizamo Yethu, Cape Town, South Africa. The findings reveal tensions between the different actors involved in township tourism. While the involvement of small, locally owned, businesses is beneficial, it is limited by conflicts of interest, lack of trust, limited social networks and little attachment to the township locality. The discussion highlights the complexity of tourism's role in economic development, which has significant implications for local policy-makers
Utilization of case presentations in medical microbiology to enhance relevance of basic science for medical students
Background : Small-group case presentation exercises (CPs) were created to increase course relevance for medical students taking Medical Microbiology (MM) and Infectious Diseases (ID) Methods : Each student received a unique paper case and had 10 minutes to review patient history, physical exam data, and laboratory data. Students then had three minutes to orally present their case and defend why they ruled in or out each of the answer choices provided, followed by an additional three minutes to answer questions. Results : Exam scores differed significantly between students who received the traditional lecture-laboratory curriculum (Group I) and students who participated in the CPs (Group II). In MM, median unit exam and final exam scores for Group I students were 84.4% and 77.8%, compared to 86.0% and 82.2% for Group II students (P < 0.018; P < 0.001; Mann-Whitney Rank Sum Test). Median unit and final ID exam scores for Group I students were 84.0% and 80.0%, compared to 88.0% and 86.7% for Group II students (P < 0.001; P < 0.001). Conclusion : Students felt that the CPs improved their critical thinking and presentation skills and helped to prepare them as future physicians
Eye movement disorders and neurological symptoms in late-onset inborn errors of metabolism
Inborn errors of metabolism in adults are still largely unexplored. Despite the fact that adult-onset phenotypes have been known for many years, little attention is given to these disorders in neurological practice. The adult-onset presentation differs from childhood-onset phenotypes, often leading to considerable diagnostic delay. The identification of these patients at the earliest stage of disease is important, given that early treatment may prevent or lessen further brain damage. Neurological and psychiatric symptoms occur more frequently in adult forms. Abnormalities of eye movements are also common and can be the presenting sign. Eye movement disorders can be classified as central or peripheral. Central forms are frequently observed in lysosomal storage disorders, whereas peripheral forms are a key feature of mitochondrial disease. Furthermore, oculogyric crisis is an important feature in disorders affecting dopamine syntheses or transport. Ocular motor disorders are often not reported by the patient, and abnormalities can be easily overlooked in a general examination. In adults with unexplained psychiatric and neurological symptoms, a special focus on examination of eye movements can serve as a relatively simple clinical tool to detect a metabolic disorder. Eye movements can be easily quantified and analyzed with video-oculography, making them a valuable biomarker for following the natural course of disease or the response to therapies. Here, we review, for the first time, eye movement disorders that can occur in inborn errors of metabolism, with a focus on late-onset forms. We provide a step-by-step overview that will help clinicians to examine and interpret eye movement disorders. (c) 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society
A Screening Tool to Quickly Identify Movement Disorders in Patients with Inborn Errors of Metabolism
Background: Movement disorders are frequent in patients with inborn errors of metabolism (IEMs) but poorly recognized, particularly by nonmovement disorder specialists. We propose an easyâtoâuse clinical screening tool to help recognize movement disorders.
Objective: The aim is to develop a userâfriendly rapid screening tool for nonmovement disorder specialists to detect moderate and severe movement disorders in patients aged â„4âyears with IEMs.
Methods: Videos of 55 patients with different IEMs were scored by experienced movement disorder specialists (n = 12). Interârater agreements were determined on the presence and subtype of the movement disorder. Based on ranking and consensus, items were chosen to be incorporated into the screening tool.
Results: A movement disorder was rated as present in 80% of the patients, with a moderate interârater agreement (Îș =0.420, PÂ <â0.001) on the presence of a movement disorder. When considering only moderate and severe movement disorders, the interârater agreement increased to almost perfect (ÎșÂ =Â 0.900, PÂ <â0.001). Dystonia was most frequently scored (27.3%) as the dominant phenotype. Treatment was mainly suggested for patients with moderate or severe movement disorders. Walking, observations of the arms, and drawing a spiral were found to be the most informative tasks and were included in the screening tool.
Conclusions: We designed a screening tool to recognize movement disorders in patients with IEMs. We propose that this screening tool can contribute to select patients who should be referred to a movement disorder specialist for further evaluation and, if necessary, treatment of the movement disorder.
© 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society
Molecular subtype-specific efficacy of anti-EGFR therapy in colorectal cancer is dependent on the chemotherapy backbone
Background
Patient selection for addition of anti-EGFR therapy to chemotherapy for patients with RAS and BRAF wildtype metastatic colorectal cancer can still be optimised. Here we investigate the effect of anti-EGFR therapy on survival in different consensus molecular subtypes (CMSs) and stratified by primary tumour location.
Methods
Retrospective analyses, using the immunohistochemistry-based CMS classifier, were performed in the COIN (first-line oxaliplatin backbone with or without cetuximab) and PICCOLO trial (second-line irinotecan with or without panitumumab). Tumour tissue was available for 323 patients (20%) and 349 (41%), respectively.
Results
When using an irinotecan backbone, anti-EGFR therapy is effective in both CMS2/3 and CMS4 in left-sided primary tumours (progression-free survival (PFS): HR 0.44, 95% CI 0.26â0.75, Pâ=â0.003 and HR 0.12, 95% CI 0.04â0.36, Pâ<â0.001, respectively) and in CMS4 right-sided tumours (PFS HR 0.17, 95% CI 0.04â0.71, Pâ=â0.02). Efficacy using an oxaliplatin backbone was restricted to left-sided CMS2/3 tumours (HR 0.57, 95% CI 0.36â0.96, Pâ=â0.034).
Conclusions
The subtype-specific efficacy of anti-EGFR therapy is dependent on the chemotherapy backbone. This may provide the possibility of subtype-specific treatment strategies for a more optimal use of anti-EGFR therapy
A screening tool to quickly identify movement disorders in patients with inborn errors of metabolism
BackgroundMovement disorders are frequent in patients with inborn errors of metabolism (IEMs) but poorly recognized, particularly by nonmovement disorder specialists. We propose an easy-to-use clinical screening tool to help recognize movement disorders.ObjectiveThe aim is to develop a user-friendly rapid screening tool for nonmovement disorder specialists to detect moderate and severe movement disorders in patients aged â„4âyears with IEMs.MethodsVideos of 55 patients with different IEMs were scored by experienced movement disorder specialists (n = 12). Inter-rater agreements were determined on the presence and subtype of the movement disorder. Based on ranking and consensus, items were chosen to be incorporated into the screening tool.ResultsA movement disorder was rated as present in 80% of the patients, with a moderate inter-rater agreement (Îș =0.420, P P ConclusionsWe designed a screening tool to recognize movement disorders in patients with IEMs. We propose that this screening tool can contribute to select patients who should be referred to a movement disorder specialist for further evaluation and, if necessary, treatment of the movement disorder. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.Neurological Motor Disorder
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