Jointly Optimized Deep Neural Networks to Synthesize Monoenergetic Images from Single-Energy CT Angiography for Improving Classification of Pulmonary Embolism

Detector-based spectral CT offers the possibility of obtaining spectral information from which discrete acquisitions at different energy levels can be derived, yielding so-called virtual monoenergetic images (VMI). In this study, we aimed to develop a jointly optimized deep-learning framework based on dual-energy CT pulmonary angiography (DE-CTPA) data to generate synthetic monoenergetic images (SMI) for improving automatic pulmonary embolism (PE) detection in single-energy CTPA scans. For this purpose, we used two datasets: our institutional DE-CTPA dataset D1, comprising polyenergetic arterial series and the corresponding VMI at low-energy levels (40 keV) with 7892 image pairs, and a 10% subset of the 2020 RSNA Pulmonary Embolism CT Dataset D2, which consisted of 161,253 polyenergetic images with dichotomous slice-wise annotations (PE/no PE). We trained a fully convolutional encoder-decoder on D1 to generate SMI from single-energy CTPA scans of D2, which were then fed into a ResNet50 network for training of the downstream PE classification task. The quantitative results on the reconstruction ability of our framework revealed high-quality visual SMI predictions with reconstruction results of 0.984 ± 0.002 (structural similarity) and 41.706 ± 0.547 dB (peak signal-to-noise ratio). PE classification resulted in an AUC of 0.84 for our model, which achieved improved performance compared to other naïve approaches with AUCs up to 0.81. Our study stresses the role of using joint optimization strategies for deep-learning algorithms to improve automatic PE detection. The proposed pipeline may prove to be beneficial for

Prediction of low-keV monochromatic images from polyenergetic CT scans for improved automatic detection of pulmonary embolism

Detector-based spectral computed tomography is a recent dual-energy CT (DECT) technology that offers the possibility of obtaining spectral information. From this spectral data, different types of images can be derived, amongst others virtual monoenergetic (monoE) images. MonoE images potentially exhibit decreased artifacts, improve contrast, and overall contain lower noise values, making them ideal candidates for better delineation and thus improved diagnostic accuracy of vascular abnormalities. In this paper, we are training convolutional neural networks~(CNN) that can emulate the generation of monoE images from conventional single energy CT acquisitions. For this task, we investigate several commonly used image-translation methods. We demonstrate that these methods while creating visually similar outputs, lead to a poorer performance when used for automatic classification of pulmonary embolism (PE). We expand on these methods through the use of a multi-task optimization approach, under which the networks achieve improved classification as well as generation results, as reflected by PSNR and SSIM scores. Further, evaluating our proposed framework on a subset of the RSNA-PE challenge data set shows that we are able to improve the Area under the Receiver Operating Characteristic curve (AuROC) in comparison to a na\"ive classification approach from 0.8142 to 0.8420.Comment: 4 pages, ISBI 202

Nagetier-übertragene Zoonosen: Beispiele aus Untersuchungen in Süd- und Westdeutschland

Zusammenfassung Nagetiere und andere Kleinsäuger können eine Vielzahl von Krankheitserregern, RNA- und DNA-Viren, Bakterien und Parasiten, auf den Menschen übertragen, die teilweise lebensbedrohliche Erkrankungen hervorrufen. In der folgenden Übersicht soll erstmals ein Überblick über Ergebnisse aus drei Untersuchungen in Deutschland gegeben werden: eine Studie in drei Landkreisen Bayerns von 2001-2004, Untersuchungen in einem Freilandgehege im Rahmen eines Tularämieausbruchs in Niedersachsen im Jahr 2005, und schließlich im Jahr 2007 eine Untersuchung an einem Truppenübungsplatz in Baden-Württemberg. Es wurde dabei exemplarisch die Verbreitung von Zoonoseerregern in Nagetieren und anderen Kleinsäugern näher untersucht, von drei Viren (Hantaviren, Kuhpockenvirus, Frühsommer- Meningo-Enzephalitis-Virus) und vier Bakterien (Leptospiren, Francisellen, Borrelien und Rickettsien). Die hier zusammengefassten Erkenntnisse sind ein erster wichtiger Schritt auf dem Weg zur Erstellung von Verbreitungskarten für die genannten humanpathogenen Zoonoseerreger in ihren Reservoirwirten und der Definition von entsprechenden Risikogebieten. Diese Arbeit soll zudem einen Beitrag leisten, einen Anstoß zu verstärkter Zusammenarbeit von Zoologen, Ökologen, Virologen, Human- und Veterinärmedizinern, Mikrobiologen, Parasitologen, Genetikern, Epidemiologen, Forstwissenschaftlern und Klimaforschern zu geben

Twenty-two points to consider for clinical trials in systemic sclerosis, based on EULAR standards

Objective. SSc is clinically and aetiopathogenically heterogeneous. Consensus standards for more uniform trial design and selection of outcome measures are needed. The objective of this study was to develop evidence-based points to consider (PTCs) for future clinical trials in SSc. Methods. Thirteen international SSc experts experienced in SSc clinical trial design were invited to participate. One researcher with experience in systematic literature review and three trainees were also included. A systematic review using PubMed and the Cochrane Central Register of Controlled Trials was conducted and PTCs when designing clinical trials in SSc were developed. As part of that development we conducted an Internet-based Delphi exercise regarding the main points to be made in the consensus statement. Consensus was defined as achieving a median score of ≥7 of 9. Results. By consensus, the experts decided to develop PTCs for each individual organ system. The current document provides a unifying outline on PTCs regarding general trial design, inclusion/exclusion criteria and analysis. Consensus was achieved regarding all the main points of the PTCs. Conclusion. Using European League Against Rheumatism suggestions for PTCs, a general outline for PTCs for controlled clinical trials in SSc was developed. Specific outlines for individual organ systems are to be published separately. This general outline should lead to more uniform and higher-quality trials and clearly delineate areas where further research is neede

Evaluation at the Federal University of Applied Adminstrative Sciences

Dulisch, Linssen und Reiter (2001) legten ein umfassendes Evaluationskonzept für die FH Bund vor. In den zehn Fachbereichen und im Zentralbereich der FH Bund erfolgt/e eine Diskussion, Modifikation und konkrete Anpassung an die Belange vor Ort. Dieser Prozess wurde in einer Evaluationtagung an der FH Bund im Juni 2003 gebündelt. Die Tagung zeigte, dass alle Fachbereiche und der Zentralbereich Fortschritte machen, wenn auch in unterschiedlichem Tempo. Dieser Band dokumentiert den Status Quo der Evaluation in den Fachbereichen und dem Zentralbereich und folgt damit § 6 Hochschulrahmengesetz (HRG), wonach die Arbeit der Hochschulen bewertet und das Ergebnis der Bewertung veröffentlicht werden soll. Inhaltsübersicht: - Evaluation an Fachhochschulen - Überblick - Empfehlungen des Benchmarking Clubs - Evaluationstagung der FH Bund 2003 - Zentralbereich - Allgemeine und Innere Verwaltung - Arbeitsverwaltung - Auswärtige Angelegenheiten - Bundesgrenzschutz - Bundeswehrverwaltung - Finanzen - Landwirtschaftliche Sozialversicherung - Öffentliche Sicherheit - Gesamtkonzept - Öffentliche Sicherheit - Abteilung Kriminalpolizei - Sozialversicherung - Wetterdiens

Arthropod communities in fungal fruitbodies are weakly structured by climate and biogeography across European beech forests

Aim The tinder fungus Fomes fomentarius is a pivotal wood decomposer in European beech Fagus sylvatica forests. The fungus, however, has regionally declined due to centuries of logging. To unravel biogeographical drivers of arthropod communities associated with this fungus, we investigated how space, climate and habitat amount structure alpha and beta diversity of arthropod communities in fruitbodies of F. fomentarius. Location Temperate zone of Europe. Taxon Arthropods. Methods We reared arthropods from fruitbodies sampled from 61 sites throughout the range of European beech and identified 13 orders taxonomically or by metabarcoding. We estimated the total number of species occurring in fruitbodies of F. fomentarius in European beech forests using the Chao2 estimator and determined the relative importance of space, climate and habitat amount by hierarchical partitioning for alpha diversity and generalized dissimilarity models for beta diversity. A subset of fungi samples was sequenced for identification of the fungus’ genetic structure. Results The total number of arthropod species occurring in fruitbodies of F. fomentarius across European beech forests was estimated to be 600. Alpha diversity increased with increasing fruitbody biomass; it decreased with increasing longitude, temperature and latitude. Beta diversity was mainly composed by turnover. Patterns of beta diversity were only weakly linked to space and the overall explanatory power was low. We could distinguish two genotypes of F. fomentarius, which showed no spatial structuring. Main conclusion Fomes fomentarius hosts a large number of arthropods in European beech forests. The low biogeographical and climatic structure of the communities suggests that fruitbodies represent a habitat that offers similar conditions across large gradients of climate and space, but are characterized by high local variability in community composition and colonized by species with high dispersal ability. For European beech forests, retention of trees with F. fomentarius and promoting its recolonization where it had declined seems a promising conservation strategy