282 research outputs found

    Remote Characterization of Physical Surface Characteristics of Mars Using Diurnal Variations in Apparent Thermal Inertia

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    Analysis of the Martian surface today can provide insight into the processes that may have affected it over its history. Information about the physical surface characterization of a region can help determine the degree of sorting it has experienced and/or its geologic maturity. Sub-resolved “checkerboard” mixtures of materials with different horizontal thermal inertia mixtures can lead to differences in the apparent thermal inertia values inferred from night and day radiance observations. Standard methods for deriving thermal inertia from orbit via the THermal EMission Imaging System (THEMIS) can give values for the same location that vary by as much as 20% between images (Fergason et al., 2006b). Such methods assume that each pixel contains material of a single, uniform thermal inertia. Here, it is proposed that if a mixture of low and high apparent thermal inertias is present within a pixel, the inferred thermal inertia will be strongly dominated by the thermal inertia of whichever surface is warmer at the time of the measurement. This effect will result in a change in thermal inertia values inferred from measurements taken at different times of day and night. Therefore, a correlation is hypothesized between the magnitude of diurnal variations in apparent thermal inertia values and the degree of non-uniformity of thermal inertias present in a given pixel location.Preliminary work has shown that the magnitude of such diurnal variation in inferred thermal inertias is sufficient to detect geologically useful differences in surfaces mixtures. Mapping the difference in apparent thermal inertias from day and night THEMIS observations may prove to be a new way of distinguishing surfaces that have relatively uniform thermal inertias from those that have mixed thermal inertias

    The Effectiveness of Prophylactic Ankle Braces in Reducing the Incidence of Acute Ankle Injuries in Adolescent Athletes: A Critically Appraised Topic

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    Clinical Scenario: Ankle injuries constitute a large number of injuries sustained by adolescent athletes participating in high school athletics. Prophylactic ankle bracing may be an effective and efficient method to reduce the incidence of ankle injuries in adolescent athletes in the secondary-school setting. Clinical Question: Do prophylactic ankle braces reduce the incidence of acute ankle injuries in adolescent athletes? Summary of Key Findings: Two of the three included studies reported that prophylactic ankle braces reduced the incidence of ankle injuries compared with no ankle bracing. Clinical Bottom Line: There is moderate evidence to support the use of prophylactic ankle braces in adolescent athletes, particularly those who participate in football and basketball, to reduce the incidence of acute ankle injuries. Strength of Recommendation: Grade B evidence exists that prophylactic ankle braces reduce the incidence of acute ankle injuries in adolescent athletes

    A Medical/Legal Teaching and Assessment Collaboration on Domestic Violence: Assessment Using Standardized Patients/Standardized Clients

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    Assessment of skills is an important, emerging topic in law school education. Two recent and influential books, Educating Lawyers published by the Carnegie Foundation and Best Practices in Legal Education, published by the Clinical Legal Education Association have both suggested dramatic reform of legal education. Among other reforms, these studies urge law schools to use “outcome-based” assessments, i.e., using learning objectives  and assessing knowledge and skills in standardized situations based on specific criteria, rather than simply comparing students’ performances to each other.

    A Medical/Legal Teaching and Assessment Collaboration on Domestic Violence: Assessment Using Standardized Patients/Standardized Clients

    Get PDF
    Assessment of skills is an important, emerging topic in law school education. Two recent and influential books, Educating Lawyers published by the Carnegie Foundation and Best Practices in Legal Education, published by the Clinical Legal Education Association have both suggested dramatic reform of legal education. Among other reforms, these studies urge law schools to use outcome-based\u27 assessments, i.e., using learning objectives and assessing knowledge and skills in standardized situations based on specific criteria, rather than simply comparing students\u27 performances to each other

    The Australian diabetes, obesity and lifestyle study (AusDiab)- methods and response rates

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    The Australian Diabetes, Obesity and Lifestyle Study (AusDiab) addresses the urgent need for data on diabetes prevalence, risk factors and associated conditions in Australia. Here we describe the methods used and the response rates obtained. AusDiab was a population-based cross-sectional survey of national diabetes mellitus prevalence and associated risk factors in people aged ⩾25 years, conducted between May 1999 and December 2000 in the six states and the Northern Territory of Australia. The study involved an initial household interview, followed by a biomedical examination that included an oral glucose tolerance test (OGTT), standard anthropometric tests, blood pressure measurements and the administration of questionnaires. Of the 20 347 eligible people (aged ⩾25 years and resident at the address for ⩾6 months) who completed a household interview, 11 247 (55.3%) attended for the biomedical examination. Of those who completed the biomedical examination 55.1% were female. Comparisons with the 1998 Australian population estimates showed that younger age responders were under-represented at the biomedical examination, while the middle-aged and older age groups were over-represented. Weighting of the AusDiab data for age and gender have corrected for this bias. AusDiab, which is the largest national diabetes prevalence study undertaken in a developed nation to have used an OGTT, provides a valuable national resource for the study of the prevalence and possible causes of diabetes, as well as identifying possible risk factors that may lead to diabetes. Furthermore, it generates the baseline data for a prospective 5-year cohort study. The data will be important for national and regional public health and lifestyle education and health promotion programs

    Novel measures of cardiovascular health and its association with prevalence and progression of age-related macular degeneration: the CHARM study

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    <p>Abstract</p> <p>Background</p> <p>To determine if novel measures of cardiovascular health are associated with prevalence or progression of age-related macular degeneration (AMD).</p> <p>Methods</p> <p>Measures of the cardiovascular system: included intima media thickness (IMT), pulse wave velocity (PWV), systemic arterial compliance (SAC), carotid augmentation index (AI). For the prevalence study, hospital-based AMD cases and population-based age- and gender-matched controls with no signs of AMD in either eye were enrolled. For the progression component, participants with early AMD were recruited from two previous studies; cases were defined as progression in one or both eyes and controls were defined as no progression in either eye.</p> <p>Results</p> <p>160 cases and 160 controls were included in the prevalence component. The upper two quartiles of SAC, implying good cardiovascular health, were significantly associated with increased risk of AMD (OR = 2.54, 95% CL = 1.29, 4.99). High PWV was associated with increased prevalent AMD. Progression was observed in 82 (32.3%) of the 254 subjects recruited for the progression component. Higher AI (worse cardiovascular function) was protective for AMD progression (OR = 0.30, 95%CL = 0.13, 0.69). Higher aortic PWV was associated with increased risk of AMD progression; the highest risk was seen with the second lowest velocity (OR = 6.22, 95% CL = 2.35, 16.46).</p> <p>Conclusion</p> <p>The results were unexpected in that better cardiovascular health was associated with increased risk of prevalent AMD and progression. Inconsistent findings between the prevalence and progression components could be due to truly different disease etiologies or to spurious findings, as can occur with inherent biases in case control studies of prevalence. Further investigation of these non-invasive methods of characterizing the cardiovascular system should be undertaken as they may help to further elucidate the role of the cardiovascular system in the etiology of prevalent AMD and progression.</p

    Search for the neutral Higgs bosons of the minimal supersymmetric standard model in pp collisions at root s=7 TeV with the ATLAS detector

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    A search for neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb-1 to 4.8 fb-1. Higgs boson decays into oppositely-charged muon or τ lepton pairs are considered for final states requiring either the presence or absence of b-jets. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived. The exclusion limits are for the production cross-section of a generic neutral Higgs boson, φ, as a function of the Higgs boson mass and for h/A/H production in the MSSM as a function of the parameters mA and tan β in the mhmax scenario for mA in the range of 90GeV to 500 GeV. Copyright CERN

    Post-traumatic glenohumeral cartilage lesions: a systematic review

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    <p>Abstract</p> <p>Background</p> <p>Any cartilage damage to the glenohumeral joint should be avoided, as these damages may result in osteoarthritis of the shoulder. To understand the pathomechanism leading to shoulder cartilage damage, we conducted a systematic review on the subject of articular cartilage lesions caused by traumas where non impression fracture of the subchondral bone is present.</p> <p>Methods</p> <p>PubMed (MEDLINE), ScienceDirect (EMBASE, BIOBASE, BIOSIS Previews) and the COCHRANE database of systematic reviews were systematically scanned using a defined search strategy to identify relevant articles in this field of research. First selection was done based on abstracts according to specific criteria, where the methodological quality in selected full text articles was assessed by two reviewers. Agreement between raters was investigated using percentage agreement and Cohen's Kappa statistic. The traumatic events were divided into two categories: 1) acute trauma which refers to any single impact situation which directly damages the articular cartilage, and 2) chronic trauma which means cartilage lesions due to overuse or disuse of the shoulder joint.</p> <p>Results</p> <p>The agreement on data quality between the two reviewers was 93% with a Kappa value of 0.79 indicating an agreement considered to be 'substantial'. It was found that acute trauma on the shoulder causes humeral articular cartilage to disrupt from the underlying bone. The pathomechanism is said to be due to compression or shearing, which can be caused by a sudden subluxation or dislocation. However, such impact lesions are rarely reported. In the case of chronic trauma glenohumeral cartilage degeneration is a result of overuse and is associated to other shoulder joint pathologies. In these latter cases it is the rotator cuff which is injured first. This can result in instability and consequent impingement which may progress to glenohumeral cartilage damage.</p> <p>Conclusion</p> <p>The great majority of glenohumeral cartilage lesions without any bony lesions are the results of overuse. Glenohumeral cartilage lesions with an intact subchondral bone and caused by an acute trauma are either rare or overlooked. And at increased risk for such cartilage lesions are active sportsmen with high shoulder demand or athletes prone to shoulder injury.</p
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