551 research outputs found
Performance of seven ECG interpretation programs in identifying arrhythmia and acute cardiovascular syndrome
Background: No direct comparison of current electrocardiogram (ECG) interpretation programs exists. Objective: Assess the accuracy of ECG interpretation programs in detecting abnormal rhythms and flagging for priority review records with alterations secondary to acute coronary syndrome (ACS). Methods: More than 2,000 digital ECGs from hospitals and databases in Europe, USA, and Australia, were obtained from consecutive adult and pediatric patients and converted to 10 s analog samples that were replayed on seven electrocardiographs and classified by the manufacturers' interpretation programs. We assessed ability to distinguish sinus rhythm from non-sinus rhythm, identify atrial fibrillation/flutter and other abnormal rhythms, and accuracy in flagging results for priority review. If all seven programs' interpretation statements did not agree, cases were reviewed by experienced cardiologists. Results: All programs could distinguish well between sinus and non-sinus rhythms and could identify atrial fibrillation/flutter or other abnormal rhythms. However, false-positive rates varied from 2.1% to 5.5% for non-sinus rhythm, from 0.7% to 4.4% for atrial fibrillation/flutter, and from 1.5% to 3.0% for other abnormal rhythms. False-negative rates varied from 12.0% to 7.5%, 9.9% to 2.7%, and 55.9% to 30.5%, respectively. Flagging of ACS varied by a factor of 2.5 between programs. Physicians flagged more ECGs for prompt review, but also showed variance of around a factor of 2. False-negative values differed between programs by a factor of 2 but was high for all (>50%). Agreement between programs and majority reviewer decisions was 46–62%. Conclusions: Automatic interpretations of rhythms and ACS differ between programs. Healthcare institutions should not rely on ECG software “critical result” flags alone to decide the ACS workflow
Performance of seven ECG interpretation programs in identifying arrhythmia and acute cardiovascular syndrome
Abstract Background No direct comparison of current electrocardiogram (ECG) interpretation programs exists. Objective Assess the accuracy of ECG interpretation programs in detecting abnormal rhythms and flagging for priority review records with alterations secondary to acute coronary syndrome (ACS). Methods More than 2,000 digital ECGs from hospitals and databases in Europe, USA, and Australia, were obtained from consecutive adult and pediatric patients and converted to 10 s analog samples that were replayed on seven electrocardiographs and classified by the manufacturers' interpretation programs. We assessed ability to distinguish sinus rhythm from non-sinus rhythm, identify atrial fibrillation/flutter and other abnormal rhythms, and accuracy in flagging results for priority review. If all seven programs' interpretation statements did not agree, cases were reviewed by experienced cardiologists. Results All programs could distinguish well between sinus and non-sinus rhythms and could identify atrial fibrillation/flutter or other abnormal rhythms. However, false-positive rates varied from 2.1% to 5.5% for non-sinus rhythm, from 0.7% to 4.4% for atrial fibrillation/flutter, and from 1.5% to 3.0% for other abnormal rhythms. False-negative rates varied from 12.0% to 7.5%, 9.9% to 2.7%, and 55.9% to 30.5%, respectively. Flagging of ACS varied by a factor of 2.5 between programs. Physicians flagged more ECGs for prompt review, but also showed variance of around a factor of 2. False-negative values differed between programs by a factor of 2 but was high for all (>50%). Agreement between programs and majority reviewer decisions was 46–62%. Conclusions Automatic interpretations of rhythms and ACS differ between programs. Healthcare institutions should not rely on ECG software "critical result" flags alone to decide the ACS workflow
Orthosymplectically invariant functions in superspace
The notion of spherically symmetric superfunctions as functions invariant
under the orthosymplectic group is introduced. This leads to dimensional
reduction theorems for differentiation and integration in superspace. These
spherically symmetric functions can be used to solve orthosymplectically
invariant Schroedinger equations in superspace, such as the (an)harmonic
oscillator or the Kepler problem. Finally the obtained machinery is used to
prove the Funk-Hecke theorem and Bochner's relations in superspace.Comment: J. Math. Phy
De Noordzee: een waardevol archief onder water. Meer dan 100 jaar onderzoek van strandvondsten en vondsten uit zee in België: een overzicht
De Noordzee kan beschouwd worden als een waardevol en speciaal archief, met heel wat interessante informatie over het verleden. De zone beneden de laagwaterlijn behoort tot het domein van de subtidale archeologie of de archeologie van het subgetijdengebied van de Noordzee.
De zone tussen de hoog- en de laagwaterlijn behoort tot de intertidale archeologie of de archeologie van het intergetijdengebied van de Noordzee.
In het eerste deel van deze studie wordt kort de geschiedenis van het onderzoek in deze beide zones geschetst. Daarna wordt in een tweede deel een chronologisch overzicht gegeven van de resultaten van het onderzoek en dit vanaf het ontstaan van de archeologie als wetenschappelijke discipline. In dit tweede deel wordt ook een klein aantal tot nu toe ongepubliceerde vondsten opgenomen van buiten het Belgische deel van de Noordzee. De reden hiervoor is zowel pragmatisch als inhoudelijk. Enerzijds worden deze vondsten geregistreerd samen met de andere vondsten, ze bevinden zich immers samen in de bestudeerde collecties. Anderzijds dragen ze ook inhoudelijk bij tot een beter inzicht in de genese van het hele zuidelijke Noordzeegebied, waarvan de zone onder Belgisch toezicht deel uitmaakt. Verder dienen in dit tweede deel ook een aantal vraagstellingen en onderzoeksstrategieën als basis voor de globale discussie in het derde deel van deze bijdrage. De bijdrage wordt ten slotte afgesloten met een zo volledig mogelijke bibliografie over het onderzoek in het Belgische deel van de Noordzee inclusief de stranden
Introductory clifford analysis
In this chapter an introduction is given to Clifford analysis and the underlying Clifford algebras. The functions under consideration are defined on Euclidean space and take values in the universal real or complex Clifford algebra, the structure and properties of which are also recalled in detail. The function theory is centered around the notion of a monogenic function, which is a null solution of a generalized Cauchy–Riemann operator, which is rotation invariant and factorizes the Laplace operator. In this way, Clifford analysis may be considered as both a generalization to higher dimension of the theory of holomorphic functions in the complex plane and a refinement of classical harmonic analysis. A notion of monogenicity may also be associated with the vectorial part of the Cauchy–Riemann operator, which is called the Dirac operator; some attention is paid to the intimate relation between both notions. Since a product of monogenic functions is, in general, no longer monogenic, it is crucial to possess some tools for generating monogenic functions: such tools are provided by Fueter’s theorem on one hand and the Cauchy–Kovalevskaya extension theorem on the other hand. A corner stone in this function theory is the Cauchy integral formula for representation of a monogenic function in the interior of its domain of monogenicity. Starting from this representation formula and related integral formulae, it is possible to consider integral transforms such as Cauchy, Hilbert, and Radon transforms, which are important both within the theoretical framework and in view of possible applications
Automating Data Science: Prospects and Challenges
Given the complexity of typical data science projects and the associated
demand for human expertise, automation has the potential to transform the data
science process.
Key insights:
* Automation in data science aims to facilitate and transform the work of
data scientists, not to replace them.
* Important parts of data science are already being automated, especially in
the modeling stages, where techniques such as automated machine learning
(AutoML) are gaining traction.
* Other aspects are harder to automate, not only because of technological
challenges, but because open-ended and context-dependent tasks require human
interaction.Comment: 19 pages, 3 figures. v1 accepted for publication (April 2021) in
Communications of the AC
Transnational knowledge in social work programs : challenges and strategies within assisted voluntary return and reintegration support
De consultatie-liaisonpsychiatrie in de Belgische ziekenhuizen van de eenentwintigste eeuw : quo vadis?
In een tijd waarin de geneeskunde zich uitsplitst in een groeiend aantal specialismen, subspecialismen en superspecialismen is er in de algemene en de universitaire ziekenhuizen een toenemende nood aan multidisciplinaire samenwerking. Deze vorm van samenwerking is nodig om hoogstaande holistische zorg te blijven verlenen aan de patiënt als centrale figuur in het zorgproces. De technologische mogelijkheden in de geneeskundige zorg nemen toe, maar er is een belangrijke comorbiditeit tussen de medische aandoeningen. De consultatie-liaisonpsychiatrie (CLP) is een van de disciplines die hierop inspeelt. Deze discipline focust vanuit een multidisciplinaire en integrale zorgvisie op de psychiatrische diagnostiek en behandeling van patiënten met psychiatrische en somatische comorbiditeit die hiervoor behandeld en opgevolgd worden in een algemeen ziekenhuis. Dit artikel wil een overzicht geven van de functies van de CLP zowel binnen als buiten het ziekenhuis en licht het historische en huidige Belgische beleid en de wetgeving ter zake toe. Er worden ook aanbevelingen geformuleerd voor de toekomst en men pleit voor de implementatie van de CLP als een volwaardige en structurele klinische activiteit en opdracht in de algemene ziekenhuizen
Abdominal aortic calcification on a plain X-ray and the relation with significant coronary artery disease in asymptomatic chronic dialysis patients
BACKGROUND: Coronary artery disease (CAD) is common in asymptomatic chronic dialysis patients and plays an important role in their poor survival. Early identification of these high-risk patients could improve treatment and reduce mortality. Abdominal aortic calcification (AAC) has previously been associated with CAD in autopsy studies. Since the AAC can be quantified easily using a lateral lumbar X-ray we hypothesized that the extent of AAC as assessed on a lateral lumbar X-ray might be predictive of the presence of significant CAD in dialysis patients. METHODS: All patients currently enrolled in the ICD2 trial without a history of CABG or a PCI with stent implantation were included in this study. All patients underwent CT-angiography (CTA) and a lateral X-ray of the abdomen. AAC on X-ray was quantified using a previously validated scoring system whereupon the association between AAC and the presence of significant CAD was assessed. RESULTS: A total of 90 patients were included in this study (71% male, 67 ± 7 years old). Forty-six patients were found to have significant CAD. AAC-score was significantly higher in patients with CAD (10.1 ± 4.9 vs 6.3 ± 4.6 (p < 0.05). Multivariate regression analysis revealed that AAC score is an independent predictor for the presence of CAD with a 1,2 fold higher risk per point increase (p < 0.01). The AAC score has a sensitivity of 85% and a specificity of 57% for the presence of significant CAD. CONCLUSION: This study shows that abdominal aortic calcification as assessed on a lateral lumbar X-ray is predictive for the presence of significant coronary artery disease in asymptomatic dialysis patients. This simple, non-invasive and cheap screening method could contribute to early identification of patients eligible for further screening of CAD. TRIAL REGISTRATION: NTR948, registered 10-4-2007 ; ISRCTN20479861, registered 2-5-200
Disease Combinations Associated with Physical Activity Identified: The SMILE Cohort Study
In the search of predictors of inadequate physical activity, an investigation was conducted into the association between multimorbidity and physical activity (PA). So far the sum of diseases used as a measure of multimorbidity reveals an inverse association. How specific combinations of chronic diseases are associated with PA remains unclear. The objective of this study is to identify clusters of multimorbidity that are associated with PA. Cross-sectional data of 3,386 patients from the 2003 wave of the Dutch cohort study SMILE were used. Ward's agglomerative hierarchical clustering was executed to establish multimorbidity clusters. Chi-square statistics were used to assess the association between clusters of chronic diseases and PA, measured in compliance with the Dutch PA guideline. The highest rate of PA guideline compliance was found in patients the majority of whom suffer from liver disease, back problems, rheumatoid arthritis, osteoarthritis, and inflammatory joint disease (62.4%). The lowest rate of PA guideline compliance was reported in patients with heart disease, respiratory disease, and diabetes mellitus (55.8%). Within the group of people with multimorbidity, those suffering from heart disease, respiratory disease, and/or diabetes mellitus may constitute a priority population as PA has proven to be effective in the prevention and cure of all three disorders
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