bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential evolution algorithm for performance optimization of the micro plasma actuator as a microelectromechanical system
Authors: Omidi Javad , Mazaheri Karim 
Published: November 2020

AbstractDielectric Discharge Barrier (DBD) plasma actuators are considered as one of the best active electro-hydrodynamic control devices, and are considered by many contemporary researchers. Here a simple electrostatic model, which is improved by authors, and uses the Maxwell’s and the Navier–Stokes equations, is proposed for massive optimization computations. This model is used to find the optimum solution for application of a dielectric discharge barrier on a curved surface of a DU25 wind turbine blade airfoil, in a range of 5–18 kV applied voltages, and 0.5 to 13 kHz frequency range. Design variables are selected as the dielectric thickness and material, and thickness and length of the electrodes, and the applied voltage and frequency. The aerodynamic performance, i.e. the lift to drag ratio of the wind turbine blade section is considered as the cost function. A differential evolution optimization algorithm is applied and we have simultaneously found the optimized value of both geometrical and operational parameters. Finally the optimized value at each voltage and frequency are sought, and the optimum aerodynamic performance is derived. The physical effect of each design variable on the aerodynamic performance is discussed. A design relation is proposed to recommend an optimum design for wind turbine applications.
Spatial transcriptomics inferred from pathology whole-slide images links tumor heterogeneity to survival in breast and lung cancer
Authors: Levy-Jurgenson Alona , Tekpli Xavier , Kristensen Vessela N. , Yakhini Zohar 
Published: November 2020

AbstractDigital analysis of pathology whole-slide images is fast becoming a game changer in cancer diagnosis and treatment. Specifically, deep learning methods have shown great potential to support pathology analysis, with recent studies identifying molecular traits that were not previously recognized in pathology H&E whole-slide images. Simultaneous to these developments, it is becoming increasingly evident that tumor heterogeneity is an important determinant of cancer prognosis and susceptibility to treatment, and should therefore play a role in the evolving practices of matching treatment protocols to patients. State of the art diagnostic procedures, however, do not provide automated methods for characterizing and/or quantifying tumor heterogeneity, certainly not in a spatial context. Further, existing methods for analyzing pathology whole-slide images from bulk measurements require many training samples and complex pipelines. Our work addresses these two challenges. First, we train deep learning models to spatially resolve bulk mRNA and miRNA expression levels on pathology whole-slide images (WSIs). Our models reach up to 0.95 AUC on held-out test sets from two cancer cohorts using a simple training pipeline and a small number of training samples. Using the inferred gene expression levels, we further develop a method to spatially characterize tumor heterogeneity. Specifically, we produce tumor molecular cartographies and heterogeneity maps of WSIs and formulate a heterogeneity index (HTI) that quantifies the level of heterogeneity within these maps. Applying our methods to breast and lung cancer slides, we show a significant statistical link between heterogeneity and survival. Our methods potentially open a new and accessible approach to investigating tumor heterogeneity and other spatial molecular properties and their link to clinical characteristics, including treatment susceptibility and survival.
Establish pre-clinical diagnostic efficacy for parathyroid hormone as a point-of-surgery-testing-device (POST)
Authors: Tanak Ambalika S. , Muthukumar Sriram , Hashim Ibrahim A. , Prasad Shalini 
Published: November 2020

AbstractMeasuring the Parathyroid hormone (PTH) levels assists in the investigation and management of patients with parathyroid disorders. Rapid PTH monitoring is a valid tool for accurate assessment intraoperatively. Rapid Electro-Analytical Device (READ) is a point-of-care device that uses impedance change between target and capture probe to assess the PTH concentration in undiluted patient plasma samples. The aim of this work focuses on evaluating the analytical performance of READ platform to Roche analyzer as a prospective clinical validation method. The coefficient of variation (CV) for intra-assay imprecision was < 5% and inter-assay imprecision CV was < 10% for high (942 pg/mL) and low (38.2 pg/mL) PTH concentration. Functional sensitivity defined at 15% CV was 1.9 pg/mL. Results obtained from READ platform correlated well (r = 0.99) with commercially available clinical laboratory method (Roche Diagnostics) to measure PTH concentrations with a turn-around time of less than 15 min. Furthermore, the mean bias of 7.6 pg/mL determined by Bland–Altman analysis, showed good agreement between the two methods. We envision such a sensing system would allow medical practitioners to facilitate targeted interventions, thereby, offering an immediate prognostic approach as the cornerstone to delivering successful treatment for patients suffering from primary hyperparathyroidism.
The RAdial Velocity Experiment (RAVE): Parameterisation of RAVE spectra based on convolutional neural networks
Authors: Guiglion G. , Matijevič G. , Queiroz A. B. A. , Valentini M. , Steinmetz M. , Chiappini C. , Grebel E. K. , McMillan P. J. , Kordopatis G. , Kunder A. , Zwitter T. , Khalatyan A. , Anders F. , Enke H. , Minchev I. , Monari G. , Wyse R. F. G. , Bienaymé O. , Bland-Hawthorn J. , Gibson B. K. , Navarro J. F. , Parker Q. , Reid W. , Seabroke G. M. , Siebert A. 
Published: November 2020

Context. Data-driven methods play an increasingly important role in the field of astrophysics. In the context of large spectroscopic surveys of stars, data-driven methods are key in deducing physical parameters for millions of spectra in a short time. Convolutional neural networks (CNNs) enable us to connect observables (e.g. spectra, stellar magnitudes) to physical properties (atmospheric parameters, chemical abundances, or labels in general).
Aims. We test whether it is possible to transfer the labels derived from a high-resolution stellar survey to intermediate-resolution spectra of another survey by using a CNN.
Methods. We trained a CNN, adopting stellar atmospheric parameters and chemical abundances from APOGEE DR16 (resolution R = 22 500) data as training set labels. As input, we used parts of the intermediate-resolution RAVE DR6 spectra (R ∼ 7500) overlapping with the APOGEE DR16 data as well as broad-band ALL_WISE and 2MASS photometry, together with Gaia DR2 photometry and parallaxes.
Results. We derived precise atmospheric parameters Teff, log(g), and [M/H], along with the chemical abundances of [Fe/H], [α/M], [Mg/Fe], [Si/Fe], [Al/Fe], and [Ni/Fe] for 420 165 RAVE spectra. The precision typically amounts to 60 K in Teff, 0.06 in log(g) and 0.02−0.04 dex for individual chemical abundances. Incorporating photometry and astrometry as additional constraints substantially improves the results in terms of the accuracy and precision of the derived labels, as long as we operate in those parts of the parameter space that are well-covered by the training sample. Scientific validation confirms the robustness of the CNN results. We provide a catalogue of CNN-trained atmospheric parameters and abundances along with their uncertainties for 420 165 stars in the RAVE survey.
Conclusions. CNN-based methods provide a powerful way to combine spectroscopic, photometric, and astrometric data without the need to apply any priors in the form of stellar evolutionary models. The developed procedure can extend the scientific output of RAVE spectra beyond DR6 to ongoing and planned surveys such as Gaia RVS, 4MOST, and WEAVE. We call on the community to place a particular collective emphasis and on efforts to create unbiased training samples for such future spectroscopic surveys.
Preliminary assessment of two novel mechanical colonoscopic polypectomy simulators: Description, evaluation and validation
Authors: Frimberger Eckart , Klare Peter , Haller Bernhard , Elnegouly Mayada , Bajbouj Monther , Schmid Roland M. , von Delius Stefan , Abdelhafez Mohamed 
Published: November 2020

Abstract
Background and study aims Colonoscopic polypectomy is an essential endoscopic skill. The simulators available for training are limited and based on raw porcine colons. Animal intestines are inconvenient and offer limited advantages for polypectomy training. These limitations are avoided by two novel mechanical simulators — the magnetic system based simulator (MSPS) and the simulator for polypectomy with high frequency current (HFPS) — described here. They are equipped to demonstrate self-repair of polyps after making a cut and hybrid polyps. The aim of this study was to describe and establish face, content, and construct validity of the two simulators and to assess their perceived utility as training and assessment tools.
Methods Ten novice, seven intermediate, and 10 advanced endoscopists participated in this study. Each one performed two polypectomies in MSPS and then one polypectomy and polyp retrieval in HFPS. The median times were compared among the three groups to preliminarily assess construct validity as a primary outcome. To establish face validity, the novices and intermediates completed a questionnaire about the credibility of each simulator after finishing the tasks. For content validity, the experts completed a questionnaire grading different aspects of the simulators’ realism and their usefulness for training.
Results All 27 participants completed the modules. Median times needed to complete the tasks in both simulators differed significantly between the participants with different levels of experience (P < 0.05). Both MSPS and HFPS received favorable scores regarding face and content validity. No technical problems were encountered.
Conclusion This study provides preliminary validation for MSPS and HFPS as useful training tools in a preclinical setting as well as during colonoscopy training. Moreover, we demonstrated the construct validity of both simulators, which confirms their use as a skill assessment tool during a colonoscopy training program.
Polyarthrose der Hand
Authors: Biehl C. , Heinrich M. , Biehl L. , Heiß C. , Szalay G. 
Published: November 2020

ZUSAMMENFASSUNGDie Polyarthrose der Hand und der Finger ist keine exklusive Erkrankung des fortgeschrittenen Lebensalters. Verletzungen und Unfälle führen zu sekundären Veränderungen an der Handwurzel und den Fingergelenken. Die Therapie umfasst konservative, interventionelle und operative Ansätze. Das primäre Ziel der konservativen Therapie ist der Erhalt der Beweglichkeit und der funktionellen Kapazität. Neben dem motorisch-funktionellen Training umfasst die Ergotherapie neben Gelenkschutz und Selbsthilfetraining die gezielte Unterstützung der individualisierten Therapie durch erforderliche Orthesen. Bei persistierenden Einschränkungen und Schmerzen, die durch konservative und interventionelle Maßnahmen nicht ausreichend therapierbar sind, kann eine operative Versorgung in Erwägung gezogen werden. Diese kann dann zu einer Verbesserung der Gesamtsituation der Hand beitragen, soweit alle anderen Therapieoptionen ausgeschöpft sind und der Leidensdruck des Patienten das Ausmaß des Eingriffes rechtfertigt.
Die Endoprothetik des Handgelenkes
Authors: Arnold Ingo 
Published: November 2020

ZUSAMMENFASSUNGIn der Vergangenheit wurde der endoprothetische Ersatz des Handgelenkes nahezu ausschließlich bei älteren, „low-demand“ Patienten und bestehender rheumatoider Arthritis durchgeführt. Ein jüngeres Lebensalter, insbesondere im Zusammenhang mit einer posttraumatischen Arthrose gilt z. T. immer noch als Kontraindikation. Dieses Dogma hat sich inzwischen mit den guten mittelfristigen Erfahrungen im Umgang mit der 4. Prothesengeneration deutlich geändert. Für die derzeit verfügbaren Implantate werden Standzeiten von 86 % nach 10 Jahren (Motec) 1, 78 % über 15 Jahre (Universal 2) 2, oder 94 % für 8 Jahre (ReMotion) berichtet 3. Hierbei ließen sich auch für die vermeintlich schwierigere Klientel der Jüngeren ein zuverlässiger Erhalt eines für die täglichen Dinge ausreichenden Bewegungsumfanges, eine zuverlässige Schmerzbefreiung und ein Zugewinn für die Griffstärke darstellen. Alternativ garantiert auch die Arthrodese des Handgelenkes keineswegs immer eine hohe Patientenzufriedenheit und niedrige Komplikationsrate. Dennoch reichen die bisherigen Publikationen, insbesondere aufgrund ihrer geringen Fallstärke, weiterhin nicht aus, um den künstlichen Handgelenkersatz über die Anwendung in wenigen Spezialzentren hinaus generell empfehlen zu können. Weiterhin lässt sich nicht beantworten, warum diesbezüglich die OP-Frequenz im Widerspruch zu den deutlich verbesserten Ergebnissen eher wieder abzunehmen scheint 4.
Entfernung der PEG-Sonde bei „Buried-Bumper“-Syndrom
Authors: Stahlberg Urte , Bojarski Christian 
Published: November 2020

ZusammenfassungDie Anlage einer „perkutanen endoskopischen Gastrostomie“ (PEG) gehört auch heute noch – neben der ERCP – zu denjenigen Interventionen in der Endoskopie mit der höchsten Komplikationsrate. Das „Buried-Bumper“-Syndrom (BBS; „begrabene Halteplatte“) als seltene aber schwere Komplikation mit einer Häufigkeit von 1–3 % bezeichnet ein Einwachsen der inneren Halteplatte einer PEG und ist in fast allen Fällen zurückzuführen auf einen Bedienungs- bzw. Pflegefehler. Eine unzureichende oder fehlende Mobilisierung der PEG kann über Wochen zu einem teilweisen oder vollständigen BBS führen. Ungünstige Begleiterkrankungen des Patienten können das Risiko eines BBS erhöhen. In aller Regel erfolgt die Vorstellung der Patienten sobald die Sonde nicht mehr bedient werden kann oder sich nicht mehr anspülen lässt. Während früher nicht selten ein chirurgischer Eingriff zur Entfernung der PEG notwendig war, kann heutzutage durch verschiedene endoskopische Techniken und Instrumente in den meisten Fällen eine Operation vermieden werden. Im folgenden Artikel werden diese Techniken vorgestellt und Tipps und Tricks für die endoskopische Mobilisierung der PEG bei BBS gegeben. Neue Anlagetechniken der PEG, wie beispielsweise die Gastropexie mit Einlage eines geblockten Gastrotubes oder die Hybrid-PEG als Kombination der Gastropexie mit der klassischen Fadendurchzugstechnik führen möglicherweise zu einem deutlich verminderten Auftreten eines BBS.
Vorsorgegastroskopie in Deutschland – erste Ergebnisse der Pilotphase der Prä-GIT-Studie
Authors: Ebigbo Alanna , Römmele Christoph , Meisinger Christa , Probst Andreas , Beyer Albert , Arnold Jochen , Beer Franz , Endlicher Esther , Schiffelholz Willibold , Linseisen Jakob , Messmann Helmut 
Published: November 2020

ZusammenfassungIm Rahmen der Prä-GIT-Studie sollen Informationen zur Prävalenz und zum Verlauf von präkanzerösen und frühmalignen Läsionen im oberen Gastrointestinaltrakt (OGIT) gewonnen sowie Hochrisikogruppen identifiziert werden. Studienteilnehmer erhalten im Rahmen einer regulären Vorsorgekoloskopie nach vorangegangener Einverständniserklärung in derselben Sitzung eine standardisierte hochauflösende Gastroskopie. Für die Hauptphase der Studie ist geplant, 5000 Teilnehmer in 30 gastroenterologischen Praxen in Bayern einzuschließen. Zur Vorbereitung wurde diese Pilotstudie durchgeführt, um die Machbarkeit des Studienprotokolls, die Akzeptanz der Untersuchung sowie die Durchführung in der „Praxis“-Realität zu prüfen.
Methodik Drei gastroenterologische Praxen in Bayern nahmen an der dreimonatigen Pilotphase von 10/2018 bis 12/2018 teil. Nach entsprechender Aufklärung wurde Patienten, die sich zur Vorsorgekoloskopie in diesen Praxen vorstellten, zusätzlich eine diagnostische Gastroskopie angeboten. Die Gastroskopien erfolgten nach einer vorgegebenen Arbeitsanweisung (Standard Operating Procedure, SOP). Zusätzlich erfolgten eine Datenerhebung zu Ernährung und Lebensstil anhand eines Selbstausfüllfragebogens sowie die Sammlung von Bioproben.
Ergebnisse Innerhalb von 3 Monaten wurden 52 Probanden in drei Praxen in Bayern in die Studie eingeschlossen. Das durchschnittliche Alter lag bei 63,4 Jahren. Die durchschnittliche Untersuchungszeit lag bei 11 Minuten, Komplikationen traten keine auf. Ein Teilnehmer zeigte einen Polyp im Bereich des Recessus piriformis, 21 Teilnehmer zeigten eine Refluxösophagitis, vier Teilnehmer einen Barrett-Ösophagus, davon einer histologisch einen Barrett-Ösophagus mit LGIEN, ein Teilnehmer wies einen Ösophaguspolyp mit leichtgradiger Plattenepitheldysplasie auf, 12 Teilnehmer eine mit Helicobacter pylori assoziierte Gastritis. Eine korpusdominante Atrophie wurde in einem Fall und ein Duodenal-Adenom mit LGIEN in zwei Fällen beschrieben. 100 % bzw. 89 % der Teilnehmer stellten eine Blut- bzw. eine Stuhlprobe für weitere Untersuchungen zur Verfügung. Alle Teilnehmer füllten zudem den Patientenfragebogen aus.
Zusammenfassung Durch die Prä-GIT-Studie soll erstmals für Deutschland eine solide Datenbasis generiert werden, um die Häufigkeiten verschiedener prämaligner und frühkanzeröser Veränderungen im oberen Gastrointestinaltrakt valide schätzen zu können. Die jetzige Pilotphase liefert wichtige Erkenntnisse zur Machbarkeit sowie zur Verbesserung der Prozesse im Rahmen der Hauptphase der Studie. Erfreulicherweise zeigte sich eine sehr große Akzeptanz der Teilnahme an der Studie.
Inter- and Intramolecular Cycloaddition Reactions of Ethenetricarboxylates with Styrenes and Halostyrenes
Authors: Yamazaki Shoko , Wang Zhichao , Iwata Kentaro , Katayama Khotaro , Sugiura Hirotaka , Mikata Yuji , Morimoto Tsumoru , Ogawa Akiya 
Published: November 2020

AbstractInter- and intramolecular cycloaddition reactions of ethenetricarboxylates with styrenes and α-halostyrenes have been investigated. The reactions of ethenetricarboxylates with styrenes or α-bromostyrenes in the presence of SnCl4 or SnBr4 stereoselectively gave 2,4-cis-substituted cyclobutanes. The intramolecular cycloaddition reactions of a series of styrene-functionalized ethenetricarboxylate amides, including in situ generated derivatives, showed high diversity of reaction modes depending on the structures and substituents of the substrates. The regioselectivity and stereoselectivity of the reactions as well as reaction mechanisms were discussed based on the DFT calculations.
DBU-Promoted Formal [4+2] Annulation Reactions of o-Chloromethyl Anilines with Azlactones
Authors: Xu Jianfeng , Ji Haojie , He Chonglong , Gao Hongjie , Fu Weijun 
Published: November 2020

AbstractAn efficient 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-mediated formal [4+2] annulation reaction of aza-ortho-quinone methides (aza-oQMs) (generated from o-chloromethyl anilines) with enolates (formed from azlactones) is disclosed, delivering biologically significant 3,4-dihydroquinolin-2(1H)-one derivatives in moderate to good yields. The salient features of this reaction include readily accessible starting materials, broad substrate scope, mild reaction conditions, removable protecting groups, and a scalable synthetic approach.
The sound of silence in association football: Home advantage and referee bias decrease in matches played without spectators
Authors: Sors Fabrizio , Grassi Michele , Agostini Tiziano , Murgia Mauro 
Published: November 2020

AbstractThe home advantage and unconscious referee bias are two well‐documented phenomena in professional sports, especially in association football. Among the various factors determining them, the crowd noise is considered as one of the most relevant; yet, the majority of previous studies could not isolate its contribution. The possibility to study the effects of crowd noise – or, better, of its absence – in an ecological context was given by the matches played behind closed doors due to the COVID‐19 pandemic. The aim of the present study was to investigate whether home advantage and referee bias still occur (and to what extent) during matches played in absence of spectators. In particular, the focus was on the first and second divisions of the top four countries in the UEFA ranking, for a total of 841 matches behind closed doors. The hypothesis was that, if these phenomena are largely due to the effect of crowd noise, the absence of spectators should reduce their occurrence. Various parameters for each of the two phenomena were considered, and the analyses revealed a reduction of home advantage and the absence of referee bias. The results bring further support to the claim that, among all the factors contributing to home advantage and referee bias, crowd noise has a relevant role. Thus, spectators can significantly contribute to determine the dynamics and the outcomes of professional football matches.
On the classical and quantum Geroch group
Authors: Peraza Javier , Paternain Miguel , Reisenberger Michael 
Published: November 2020

Abstract
The Geroch group is an infinite dimensional transitive group of symmetries of classical cylindrically symmetric gravitational waves which acts by non-canonical transformations on the phase space of these waves. Here this symmetry is re derived and the unique Poisson bracket on the Geroch group which makes its action on the gravitational phase space Lie–Poisson is obtained. Two possible notions of asymptotic flatness are proposed that are compatible with the Poisson bracket on the phase space, and corresponding asymptotic flatness preserving subgroups of the Geroch group are defined which turn out to be compatible with the Poisson bracket on the group. A quantization of the Geroch group is proposed that is similar to, but distinct from, the

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Yangian, and a certain action of this quantum Geroch group on gravitational observables is shown to preserve the commutation relations of Korotkin and Samtleben’s quantization of asymptotically flat cylindrically symmetric gravitational waves. The action also preserves three of the additional conditions that define their quantization. It is conjectured that the action preserves the remaining two conditions (asymptotic flatness and a unit determinant condition on a certain basic field) as well and is, in fact, a symmetry of their model. Our results on the quantum theory are formal, but a fairly detailed outline of how these results might be formulated rigorously within the framework of algebraic quantum theory is provided.
Non-oscillating power spectra in loop quantum cosmology
Authors: Navascués Beatriz Elizaga , Mena Marugán Guillermo A , Prado Santiago 
Published: November 2020

Abstract
We characterize in an analytical way the general conditions that a choice of vacuum state for the cosmological perturbations must satisfy to lead to a power spectrum with no scale-dependent oscillations over time. In particular, we pay special attention to the case of cosmological backgrounds governed by effective loop quantum cosmology and in which the Einsteinian branch after the bounce suffers a pre-inflationary period of decelerated expansion. This is the case more often studied in the literature because of the physical interest of the resulting predictions. In this context, we argue that non-oscillating power spectra are optimal to gain observational access to those regimes near the bounce where loop quantum cosmology effects are non-negligible. In addition, we show that non-oscillatory spectra can indeed be consistently obtained when the evolution of the perturbations is ruled by the hyperbolic equations derived in the hybrid loop quantization approach. Moreover, in the ultraviolet regime of short wavelength scales we prove that there exists a unique asymptotic expansion of the power spectrum that displays no scale-dependent oscillations over time. This expansion would pick out the natural Poincaré and Bunch–Davies vacua in Minkowski and de Sitter spacetimes, respectively, and provides an appealing candidate for the choice of a vacuum for the perturbations in loop quantum cosmology based on physical motivations.