bluuebunny/crossref_metadata_2025 huggingface dataset:
Strain-enhanced sensitivity of polymeric sensors templated from cholesteric liquid crystals
Authors: Batir Ozge , Bat Erhan , Bukusoglu Emre
Published: June 2020

Strain along the cholesteric axis increases the sensitivity of the polymeric sensors templated from cholesteric liquid crystals.
Enveloping SiOx in N-doped carbon for durable lithium storage via an eco-friendly solvent-free approach
Authors: Hu Guangwu , Zhong Kunzhe , Yu Ruohan , Liu Zhenhui , Zhang Yuanyuan , Wu Jinsong , Zhou Liang , Mai Liqiang
Published: June 2020

A solvent-free, flammable gas-free method is developed for the scalable synthesis of SiOx@N-doped carbon (SiOx@NC). The obtained SiOx@NC manifests high specific capacity (774 mA h g−1) with excellent durability in lithium storage.
Semi-conducting mixed-valent X4TCNQI−/II− (X = H, F) charge-transfer complexes with C6H2(NH2)4
Authors: Sutton Ashley L. , Abrahams Brendan F. , D’Alessandro Deanna M. , Goerigk Lars , Hudson Timothy A. , Robson Richard , Usov Pavel M.
Published: June 2020

A pair of semi-conducting, charge transfer complexes of composition, [C6H2(NH2)4][TCNQ] and [C6H2(NH2)4][F4TCNQ] is described in which the TCNQ and F4TCNQ species each exhibit a -I/-II mixed-valent state.
Chromogenic covalent organic polymer-based microspheres as solid-state gas sensor
Authors: Subodh  , Prakash Kunal , Masram Dhanraj T.
Published: June 2020

A new micro-spherical covalent organic polymer was synthesized, which exhibits reversible chromogenic response towards the sensitive detection of the noxious HCl gas.
Protective effect of anisodamine hydrobromide on lipopolysaccharide-induced acute kidney injury
Authors: Wan Feng , Du Xiaoqiang , Liu Huan , He Xueling , Zeng Ye
Published: June 2020

Anisodamine hydrobromide (AniHBr) is a Chinese medicine used to treat septic shock. However, whether AniHBr could ameliorate septic acute kidney injury and the underlying mechanism were not investigated. In the present study, 18 male Sprague-Dawley rats (200–250 g) were randomly divided into control, lipopolysaccharide (LPS) and LPS+AniHBr groups. Rats were intravenously administrated with LPS or normal saline (for control). After 4 h, the rats were intravenously administrated with AniHBr (LPS+AniHBr) or normal saline at 4 h intervals. Hemodynamic parameters including blood pressure and heart rate were measured. The histopathologic evaluation of kidney tissues was performed. Lactate, creatine kinase, inflammatory cytokines and oxidative stress indicators were determined. Using Seahorse analysis, the metabolic analysis of mitochondrial stress and glycolytic stress in human renal proximal tubular epithelial cells treated with TNF-α in the presence of AniHBr was performed. AniHBr administration significantly reduced serum creatine kinase and lactate following LPS treatment. AniHBr significantly improved hemodynamics in sepsis rats including increase in the mean atrial pressure and reduction in the heart rate. AniHBr significantly attenuated LPS-induced TNF-α, IL-6 and IL-1β in serum, and LPS-induced TNF-α and IL-1β in renal tissues. The LPS-reduced SOD activity and LPS-increased MDA content were reversed by AniHBr. In vitro, TNF-α increased mitochondrial oxygen consumption and glycolysis, but inhibited the ATP generation, which was reversed by AniHBr. Thus, AniHBr protects against the LPS-induced inflammatory cytokines, mitochondrial dysfunction and oxidative stress, and thus attenuates the LPS-induced acute kidney injury, showing AniHBr is a promising therapeutic drug for septic kidney injury.
Granule regulation by phase separation during Drosophila oogenesis
Authors: Sankaranarayanan M. , Weil Timothy T.
Published: June 2020

Drosophila eggs are highly polarised cells that use RNA–protein complexes to regulate storage and translational control of maternal RNAs. Ribonucleoprotein granules are a class of biological condensates that form predominantly by intracellular phase separation. Despite extensive in vitro studies testing the physical principles regulating condensates, how phase separation translates to biological function remains largely unanswered. In this perspective, we discuss granules in Drosophila oogenesis as a model system for investigating the physiological role of phase separation. We review key maternal granules and their properties while highlighting ribonucleoprotein phase separation behaviours observed during development. Finally, we discuss how concepts and models from liquid–liquid phase separation could be used to test mechanisms underlying granule assembly, regulation and function in Drosophila oogenesis.
Misalignment‐tolerant integrated IPT systems for tram logistics robots featuring dual‐purpose coupler
Authors: Wang Junhua , Qu Haoyue , Tao Bingquan , Cai Changsong , Lin Zhongzheng , Xie Lijun , Zhang Fan
Published: June 2020

This study proposes a misalignment‐tolerant integrated inductive power transfer (IPT) system for tram logistics robots and presents an adapted parameter tuning method for the IPT system. A novel dual‐purpose coupler, which could undertake the responsibility of power transmission and self‐compensation is realised by substituted partially with compensation inductors of inductor–capacitor–capacitor networks, resulting in an integrated and cost‐effective system configuration. With the analysis of working principles on the IPT system and considerations of operation conditions on logistics robots, an adapted parameter tuning method is provided to maximise system misalignment tolerance and maintain high efficiency of power transfer. To demonstrate the validity and safety of the proposed system, comparative simulations and security evaluations are conducted by finite element analysis. Besides, the constant‐current output characteristic is simulated and proved. Finally, a 60.20 W experimental prototype is built. Results show that the system can operate stably with 87.31% efficiency at well‐aligned cases and the power fluctuation is confined below 9% within −120 to 120 mm x ‐misalignment, −80 to 80 mm y ‐misalignment, −50 to 12.5 mm z ‐misalignment, and −30° to 30° rotatory misalignment. It is also verified that the system could operate safely without any secondary side.
Multi‐stage risk‐based dispatch considering short‐term reliability of transmission lines
Authors: Lou Xian‐Si , Guo Chuang‐Xin , Ding Yi , Chen Wei
Published: June 2020

The reliability of transmission lines (TLs) has great influences on the safe operation of power systems. Random failures from TLs can be caused by multiple uncertainties such as the high load current. In this study, a multi‐stage risk‐based dispatch model is proposed to minimise the sum of generation cost and risk cost. Impacts of natural ageing, load current, health condition and disaster weather on the short‐term reliability of TLs are studied. For ensuring the operation security of power systems in the post‐contingency stage, the dynamic thermal rating (DTR) technology is implemented to improve capacities of TLs for coping with the potential overload. In order to solve this non‐linear optimiation problem caused by load current‐dependent failure probabilities and thermal rating constraints, a double‐iteration solving strategy is proposed. In exterior iterations, the sequential linear programming is applied to decouple bilinear terms of the risk cost and locally linearise failure probabilities. Meanwhile, in interior iterations, the Benders decomposition is utilised to further divide the model into the main problem and the sub‐problem for coordinating the preventive and corrective control and checking the feasibility of DTR, respectively. Proposed approaches are validated on a modified IEEE 24‐bus test system.
Distributionally robust multi‐period energy management for CCHP‐based microgrids
Authors: Shi Zhichao , Liang Hao , Dinavahi Venkata
Published: June 2020

To improve the overall energy utilisation efficiency, the research of combined cooling, heat, and power (CCHP)‐based microgrids has become prevalent recently. However, the increasing penetration of uncertain renewable generation such as wind power brings new challenges to CCHP‐based microgrids energy management. In this study, the authors propose a two‐stage multi‐period distributionally robust energy management model for CCHP‐based microgrids, and this model considers the non‐anticipativity of uncertainty in dispatch process. A second‐order conic representable ambiguity set is designed to capture the uncertainty of wind power. Based on linear decision rule approximation, the proposed problem is transformed into a tractable mixed‐integer second‐order conic programme problem. Case studies and comparison experiments are conducted in the Matlab environment with real‐world data to validate the performance of the proposed approach. Particularly, the proposed method achieves a less conservative solution and smaller cost compared with a robust optimisation method with the same reliability guarantee. In addition, it is more reliable than the deterministic method which does not consider uncertainty.
Stochastic re-acceleration and magnetic-field damping in Tycho’s supernova remnant
Authors: Wilhelm A. , Telezhinsky I. , Dwarkadas V. V. , Pohl M.
Published: June 2020

Context. Tycho’s supernova remnant (SNR) is associated with the historical supernova (SN) event SN 1572 of Type Ia. The explosion occurred in a relatively clean environment, and was visually observed, providing an age estimate. This SNR therefore represents an ideal astrophysical test-bed for the study of cosmic-ray acceleration and related phenomena. A number of studies suggest that shock acceleration with particle feedback and very efficient magnetic-field amplification combined with Alfvénic drift are needed to explain the rather soft radio spectrum and the narrow rims observed in X-rays.

Aims. We show that the broadband spectrum of Tycho’s SNR can alternatively be well explained when accounting for stochastic acceleration as a secondary process. The re-acceleration of particles in the turbulent region immediately downstream of the shock should be efficient enough to impact particle spectra over several decades in energy. The so-called Alfvénic drift and particle feedback on the shock structure are not required in this scenario. Additionally, we investigate whether synchrotron losses or magnetic-field damping play a more profound role in the formation of the non-thermal filaments.

Methods. We solved the full particle transport equation in test-particle mode using hydrodynamic simulations of the SNR plasma flow. The background magnetic field was either computed from the induction equation or follows analytic profiles, depending on the model considered. Fast-mode waves in the downstream region provide the diffusion of particles in momentum space.

Results. We show that the broadband spectrum of Tycho can be well explained if magnetic-field damping and stochastic re-acceleration of particles are taken into account. Although not as efficient as standard diffusive shock acceleration, stochastic acceleration leaves its imprint on the particle spectra, which is especially notable in the emission at radio wavelengths. We find a lower limit for the post-shock magnetic-field strength ∼330 μG, implying efficient amplification even for the magnetic-field damping scenario. Magnetic-field damping is necessary for the formation of the filaments in the radio range, while the X-ray filaments are shaped by both the synchrotron losses and magnetic-field damping.
Analysis, predictive modelling and multi-response optimization in electrical discharge machining of Al-22%SiC metal matrix composite for minimization of surface roughness and hole overcut
Authors: Naik Subhashree , Das Sudhansu Ranjan , Dhupal Debabrata
Published: June 2020

Due to the widespread engineering applications of metal matrix composites especially in automotive, aerospace, military, and electricity industries; the achievement of desired shape and contour of the machined end product with intricate geometry and dimensions that are very challenging task. This experimental investigation deals with electrical discharge machining of newly engineered metal matrix composite of aluminum reinforced with 22 wt.% of silicon carbide particles (Al-22%SiC MMC) using a brass electrode to analyze the machined part quality concerning surface roughness and overcut. Forty-six sets of experimental trials are conducted by considering five machining parameters (discharge current, gap voltage, pulse-on-time, pulse-off-time and flushing pressure) based on Box-Behnken's design of experiments (BBDOEs). This article demonstrates the methodology for predictive modeling and multi-response optimization of machining accuracy and surface quality to enhance the hole quality in Al-SiC based MMC, employing response surface methodology (RSM) and desirability function approach (DFA). Finally, a novel approach has been proposed for economic analysis which estimated the total machining cost per part of rupees 211.08 during EDM of Al-SiC MMC under optimum machining conditions. Thereafter, under the influence of discharge current several observations are performed on machined surface morphology and hole characteristics by scanning electron microscope to establish the process. The result shows that discharge current has the significant contribution (38.16% for Ra, 37.12% in case of OC) in degradation of surface finish as well as the dimensional deviation of hole diameter, especially overcut. The machining data generated for the Al-SiC MMC will be useful for the industry.
Les recours à l’objet numérique. Du mécanisme de défense à l’espace potentiel
Authors: Pitteri Aleksandra
Published: June 2020

Le recours compulsif à l’espace numérique compris en tant qu’objet externe s’exprime notamment par un surengagement des éléments sensori-moteurs et prend, dans ce contexte, la place d’un mécanisme de défense contre les angoisses débordantes. Cependant, cette répétition peut également être considérée comme une incessante tentative d’actualisation à travers la virtualité numérique des éléments virtuels de la vie psychique, autrement dit des éléments latents en devenir. L’instauration de cette dynamique d’actualisation de la potentialité interne dans le monde pixélisé peut être ensuite réutilisée en séances, nous servant d’un réel accélérateur du travail analytique. Mots clés
Sensations, perceptions, images psychiques et représentations chez l’homme connecté
Authors: Tordo Frédéric
Published: June 2020

L’auteur propose la description d’un modèle qui explicite la refiguration de sensibilités en relation avec une technologie – l’implant magnétique est utilisé ici comme exemple princeps. Dans un premier temps, l’individu connecté éprouve plusieurs sensations. Une connexion primaire se forme alors entre ces sensations, par l’intermédiaire d’une perception de l’éprouvé, c’est-à-dire d’une première interprétation. C’est le point d’appui de la transformation du schéma corporel, à l’endroit même de l’éprouvé provoqué par la technologie. À partir de cet ensemble corporel formé par un groupement de sensations-perceptions, sa représentation advient, sous la forme d’une part de l’image de la chose corporelle et d’autre part, de l’image de mot de l’image de la chose corporelle (connectée). Une connexion secondaire (hybridation psychique) se met alors en place, par appui sur des fantasmes d’intégration, entre l’expérience corporelle et la technologie. Se constitue ainsi une expérience hybride fondée sur la représentation de l’expérience corporelle, d’un côté, de la technologie et de son fonctionnement en relation avec le corps, de l’autre. Le Moi-cyborg (Tordo, 2019) apparaît comme le maître d’œuvre de ces transformations.
Transmission intergénérationnelle de la violence dans les liens filiatifs : héritage de la mémoire traumatique dans le contexte historique à l’île de la Réunion
Authors: Fontaine Émilie , Govindama Yolande , Ève Prosper
Published: June 2020

L’objectif de cet article vise à introduire une nouvelle réflexion sur la violence intergénérationnelle à partir du traumatisme historique de l’esclavage à la Réunion et son impact psychologique sur une partie de la population locale. Dans une perspective psychodynamique et anthropologique, il s’agit de confronter notre hypothèse de travail, à travers l’analyse d’un cas, à savoir : comment l’individu réunionnais se réinterprète cette histoire et se reconstruit une identité individuelle et collective, à travers l’héritage entre générations et les reviviscences présentes dans l’inconscient collectif.

Le cas clinique présenté est tiré d’un travail de thèse. Il s’agit d’une recherche non-intervention-nelle, réalisée au sein de l’association le Réseau VIF (Violence Intra-Familiale), avec pour méthodologie la passation d’entretiens de recherche semi-directifs, étayés par l’utilisation d’un génogramme, suivi d’une analyse thématique. L’idée étant la mise en évidence de l’expression de la violence intergénérationnelle dans les liens filiatifs, dans l’émergence des pathologies qui y seraient associées, pour appréhender le sujet dans sa globalité, en intégrant son historicité. De part l’orientation vers le traumatisme historique, nous serons amenés à effectuer la distinction entre l’« inter » et le « trans » générationnel, à travers la notion de répétition, d’une transmission en négatif vers une transmission de ce qui manque ou fait défaut.
Duchamp et son « coefficient d’art » : variation de l’inadéquation radicale de l’inconscient
Authors: Farriol Cristóbal
Published: June 2020

Y a-t-il une entité de l’art ? Pour Duchamp oui, à condition d’en faire une entité vide, produit d’une non-coïncidence entre l’intention de l’artiste et l’interprétation du spectateur. Plus cet écart est accentué, plus l’objet artistique porte ce qu’il nomme « le coefficient d’art ». Nous proposons l’hypothèse d’une correspondance entre l’inadéquation propre au coefficient d’art duchampien, et l’inadéquation propre à l’inconscient. Pour l’argumenter, nous travaillerons le texte « Le processus créatif », et parcourions les moments chez Freud où quelque chose de l’inadéquation est en jeu dans la structure de l’inconscient. Ensuite, nous verrons chez Lacan l’une de ses formalisations pour une inadéquation fondatrice du sujet : aliénation et séparation. Le résultat de cette analyse nous permettra d’argumenter une certaine équivalence entre l’objet artistique selon Duchamp et l’objet cause du désir chez Lacan.
L’Obsédé, un pamphlet bien pensant. Avec des lettres de Freud et de Janet
Authors: Wacjman Claude
Published: June 2020

Lelivre d’André Gaucher, L’obsédé (1925) est à charge contre Léon Daudet dont le fils Philippe s’est suicidé. C’est une tentative pour introduire les effets de la tare héréditaire (hérédo). Cet ouvrage s’appuie sur les théories de Pierre Janet et de Sigmund Freud. L’auteur fait paraître sa correspondance avec ceux-ci. Peu connue, elle est transcrite ici.
Konservative und operative Behandlung der Rhizarthrose
Authors: Seyhan Harun
Published: June 2020

Treten belastungsabhängige, anhaltende Schmerzen im Daumensattelgelenk auf, könnte eine Rhizarthrose zugrunde liegen. Was beinhaltet die ärztliche Diagnostik? Welche Erkrankungen sollten differenzialdiagnostisch ausgeschlossen werden? Welche konservativen und operativen Behandlungsmöglichkeiten gibt es und nach welchen Kriterien wählt der Arzt sie aus?
Die Hörrehabilitation mittels Cochlea-Implantat – Eine Möglichkeit der Tinnitus-Reduktion im Alter
Authors: Issing Christian , Baumann Uwe , Pantel Johannes , Stöver Timo
Published: June 2020

Hintergrund Tinnitus ist ein häufiges Begleitsymptom einer hochgradigen Hörminderung oder Ertaubung auch bei älteren Menschen. Die Hörrehabilitation dieser Patienten ist in der Regel nur noch mit einem Cochlea-Implantat (CI) möglich. In den letzten Jahren werden immer mehr ältere und sehr alte Patienten mit einem CI versorgt. Ziel dieser Studie war die Untersuchung des Einflusses der Hörrehabilitation mit einem CI auf die Tinnitus-Belastung älterer Menschen.

Material und Methoden In diese prospektive Untersuchung wurden 34 Patienten zwischen dem 65. und 86. Lebensjahr eingeschlossen, die erstmalig unilateral mit einem CI versorgt wurden. 16 Patienten (47,1 %) hatten präoperativ einen Tinnitus. Zu je 3 Zeitpunkten (präoperativ, bei Erstanpassung und 6 Monate postoperativ) erfolgte bei den Patienten mit Tinnitus neben der Erfassung des Sprachverstehens die Erhebung der Tinnitus-Belastung mit dem Mini-Tinnitus-Fragebogen (Mini-TF12).

Ergebnisse Sechs Monate postoperativ fanden wir eine hochsignifikante Verbesserung des Sprachverstehens von präoperativ 11,5 ± 17,4 auf 54,4 ± 28,1 % (p = 0,001), die von einer hochsignifikanten Reduktion der mit dem Mini-TF12-Fragebogen erfassten Tinnitus-Belastung von 6,9 ± 6,5 Punkten präoperativ auf 4,3 ± 3,3 Punkte nach 6 Monaten (p = 0,001) begleitet war.

Schlussfolgerungen Die Hörrehabilitation mittels CI führt beim älteren Menschen zu einer hochsignifikanten Reduktion der subjektiven Belastung durch einen bereits präoperativ bestehenden Tinnitus.
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: June 2020

Im 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.
Diagnostische Güte der transluminalen Biopsie bei unklaren Gallenwegstenosen im Rahmen der primären PTCD-Anlage mit der „Cross and Push“-Technik – eine prospektive monozentrische Pilotstudie
Authors: Lutz Holger H. , Trautwein Christian , Tischendorf Jens J.W.
Published: June 2020

Hintergrund Bei Vorliegen einer Stenose der Gallenwege kann die histologische Charakterisierung für die weiteren Therapiemaßnahmen entscheidend sein. Nicht bei jedem Patienten ist ein Zugang zur Stenose mittels endoskopischer retrograder Cholangiografie (ERC) möglich. In diesen Fällen kann eine perkutane transhepatische Cholangiodrainage (PTCD) hilfreich sein. Die optimale Technik und die diagnostische Wertigkeit einer Biopsie im Rahmen der PTCD sind allerdings nicht hinreichend evaluiert.

Methoden In einem Zeitraum von 24 Monaten wurde nach einer Trainingsphase von 10 Patienten bei insgesamt 30 Patienten mit Stenose der Gallenwege und fehlender adäquater Ableitungsmöglichkeit mittels ERC eine PTCD angelegt. Dabei wurde die Stenose mit einem Draht passiert und anschließend die gezielte Zangenbiopsie der Stenose unter Zuhilfenahme einer drahtgeführten Einführschleuse (7-Fr-Innendurchmesser) in einer „Cross and Push“-Technik (Transluminal Biliary Biopsy Forceps Set, Cook Medical™) durchgeführt. Das Ergebnis der histologischen Begutachtung der Biopsien wurde anschließend mit der definitiven Diagnose korreliert. Die Nachbeobachtungszeit betrug 18 Monate.

Ergebnis Von insgesamt 30 Patienten wiesen 22 (73 %) eine maligne Stenose (10 Gallenwegneoplasien, 12 nichtbiliäre Karzinome/Metastasen/Lymphome) auf. Acht (27 %) der 30 Patienten hatten eine benigne Stenose. Bei allen 30 Patienten erbrachte die Biopsien ausreichendes Material zur histologischen Begutachtung. Die Subgruppenanalyse wurde für Gallenwegtumoren und nichtbiliäre Tumoren durchgeführt. Dabei wurde in 8 von 10 Patienten mit einer Gallenwegneoplasie die Stenose auch histologisch als maligne klassifiziert (Sensitivität 80 %), während dies nur in 8 von 12 nichtbiliären Tumoren gelang (Sensitivität 66,6 %, Unterschied n. s., p = 0,0577). Bei allen Patienten mit benigner Stenose zeigte sich auch in der histologischen Beurteilung der Biopsien ein benigner Befund (Spezifität 100 %). Interventionsbedingte Komplikationen traten nicht auf.

Schlussfolgerung In dieser prospektiven Kohortenstudie weist das perkutane transduktale Biopsieset eine relative hohe diagnostische Genauigkeit zur Abklärung einer unklaren Gallengangsstenose – insbesondere bei biliären Prozessen – auf. Auch aufgrund der teils schwierigen anderweitigen Histologiegewinnung bei malignen Gallenwegprozessen ergänzt die „Cross and Push“-Biopsie das Spektrum der diagnostischen Verfahren.
Positionspapier: Anwendung von Biologika bei chronischer Rhinosinusitis mit Polyposis nasi (CRSwNP) im deutschen Gesundheitssystem – Empfehlungen des Ärzteverbandes Deutscher Allergologen (AeDA) und der AGs Klinische Immunologie, Allergologie und Umweltmedizin und Rhinologie und Rhinochirurgie der Deutschen Gesellschaft für HNO-Heilkunde, Kopf- und Halschirurgie (DGHNOKHC)
Authors: Klimek L. , Förster-Ruhrmann U. , Becker S. , Chaker A. , Strieth S. , Hoffmann T. K. , Dazert S. , Deitmer T. , Olze H. , Glien A. , Plontke S. , Wrede H. , Schlenter W. , Welkoborsky H. J. , Wollenberg B. , Beule A. G. , Rudack C. , Wagenmann M. , Stöver T. , Huppertz T. , Hagemann J. , Bachert C.
Published: June 2020

Hintergrund Die chronische Rhinosinusitis (CRS) betrifft weltweit ca. 5–12 % der Allgemeinbevölkerung und wird traditionell eingeteilt in einen Phänotyp ohne (CRSsNP) und einen mit Ausbildung von Nasenpolypen (CRSwNP). Wurden Nasenpolypen bis vor kurzem eher als mechanisches Hindernis mit der Notwendigkeit einer operativen Beseitigung betrachtet, wird die CRSwNP heute als eine multifaktorielle entzündliche Erkrankung der nasalen und paranasalen Schleimhäute angesehen, der als Endotyp häufig eine T2-Inflammation zugrunde liegt. Biologika, die mit diesen Entzündungsmechanismen interferieren, stellen interessante neue Therapiemöglichkeiten dar.

Methoden Das aktuelle Wissen zur Immunologie der CRSwNP und Wirkung von Biologika wurde mittels einer Literaturanalyse durch Recherchen in Medline, PubMed sowie den nationalen und internationalen Studien- und Leitlinienregistern und der Cochrane Library zusammengestellt.

Ergebnisse Basierend auf der internationalen Literatur und bisherigen Erfahrungen werden von einem Expertengremium Empfehlungen für die Anwendung von Biologika bei CRSwNP im deutschen Gesundheitssystem auf der Grundlage eines Dokumentationsbogens gegeben.

Schlussfolgerung Das Verständnis über die immunologischen Grundlagen der CRSwNP eröffnet neue nichtoperative Therapieansätze mit Biologika für Patienten mit schweren Verlaufsformen.
Balancing the Loudness in Speech Processors and Contralateral Hearing Aids in Users of Unilateral Cochlear Implants
Authors: Magalhães Ana Tereza Matos , Carvalho Amanda , Tsuji Robinson Koji , Bento Ricardo Ferreira , Goffi-Gomez Maria Valéria Schmidt
Published: June 2020

Introduction The use of cochlear implants and hearing aids (bimodal) has been growing with the expansion of the indication for them, and it is important to ensure protocols so that there is a balance of the loudness regarding the two devices.

Objective To evaluate if the limited complex sounds present in the frequency bands of the current devices enable the balance of the loudness in adult users of bimodal stimulation, and to analyze if speech recognition improves after balancing.

Methods A prospective cross-sectional study with convenience sampling. The sample was composed of 25 adults who had used either a cochlear implant for at least 6 months or a contralateral hearing aid, with a mean age of 46 years. The balancing of the loudness was performed in an acoustic room with the computer's sound box (0° azimuth at 70 dB SPL). The instrumental sounds were filtered through eight different frequency bands. The patients used both hearing devices and were asked if the sound was perceived to be louder in one of the ears or centrally. The speech test was evaluated with sentence silence (65 dB SPL) and/or noise signal ratio of 0 dB/+ 10 dB in free field at 0° azimuth, before and after balancing.

Results: Out of the 25 patients, 5 failed to achieve balance at every tested frequency, and 3 achieved balance at almost every frequency, except 8 kHz. There was a significant difference between the speech recognition test only in silence before and after balancing.

Conclusion: Most patients achieved sound equalization at all evaluated frequencies under the complex-sound protocol. Additionally, most patients experienced improved speech recognition after balancing.
Prevalence of Post-Interview Communication in the Ophthalmology Match and Its Impact on Program Directors' Ranking of Applicants
Authors: Cui David , Behunin Nicholas L. , Scott Ingrid U. , Wingert Heidi Luise
Published: June 2020

Objective The aim of this study is to investigate the prevalence of post-interview communication (PIC) during the ophthalmology residency match process and its impact on program directors' (PD's) ranking of applicants.

Design Prospective cross-sectional survey.

Methods An anonymous, online survey was emailed to the PD of each ophthalmology residency program accredited by the Accreditation Council for Graduate Medical Education.

Results Fifty-four percent (63/116) of PDs completed the survey. Eighty-five percent (54/63) of PDs received PIC from applicants or applicants' faculty mentors during the 2018 to 2019 application cycle; 62% (39/63) received PIC regarding >25% of applicants interviewed. Although 41% (26/63) of PDs reported they would likely rank an applicant higher due to PIC endorsement from a faculty mentor known to the PD, only 3% (2/63) believed that applicants who did not have a faculty mentor conduct PIC on their behalf were disadvantaged. Fourteen percent (9/63) of PDs reported they would likely rank an applicant higher due to PIC endorsement from a faculty mentor unknown to the PD, and 3% (2/63) reported they would likely rank an applicant higher as a result of PIC from the applicant.

Conclusion There is a high prevalence of PIC during the ophthalmology residency match process. The potential impact of PIC on PDs' ranking of applicants varies according to whether the PIC is from a faculty member known to the PD, a faculty member unknown to the PD, or the applicant. This may disadvantage applicants without faculty mentors known to PDs.
Sound Generator: Analysis of the Effectiveness of Noise in the Habituation of Tinnitus
Authors: Mondelli Maria Fernanda Capoani Garcia , Cabreira Aline Faure , Matos Izabella Lima de , Ferreira Maria Carolina , Rocha Andressa Vital
Published: June 2020

Introduction Tinnitus is a disorder that affects 10 to 15% of de world's population. Sound therapy performed through hearing aids (HAs) with integrated sound generator (SG) is one of the forms of tinnitus treatment.

Objective To analyze the effectiveness of four masking noises in relieving tinnitus in individuals with mild and moderate bilateral sensorineural hearing loss and their influence in speech perception.

Methods The participants were 35 individuals with tinnitus and mild and moderate bilateral sensorineural hearing loss, divided into four groups. All groups underwent HA and SG adaptation, being regulated in the combined mode (HA and SG). In group 1 (G1), the white noise stimulus was applied, in group 2 (G2), pink noise was applied, in group 3 (G3), speech noise, and in group 4 (G4), the high tone was applied. All patients were subjected to the following procedures: audiological diagnosis, acuphenometry, tinnitus handicap inventory (THI), visual analogue scale (VAS), and hearing in noise test (HINT). The procedures were performed prior to and after hearing intervention, and after 3 months of use of HA and SG.

Results All groups presented a statistically significant difference for the THI, VAS, and HINT pre and postintervention. In the case of the HINT, only pink noise presented a significant difference. However, in the comparation among groups there was no significant difference.

Conclusion The present study made it possible to conclude that the four noises were equally effective in relieving tinnitus, with no statistically significant differences between the analyzed groups.
Small Bowel Angiodysplasia Managed with Novel Motorized Spiral Enteroscope: A Case Report
Authors: Kothakota Sunil Raviraj , Sasidharan Madhu , Kareem Harish , Nair Ajith K.
Published: June 2020

We report a case of 72-year-old woman, who presented with complaints of melena associated with shortness of breath on exertion for more than 2 weeks. On evaluation, she was diagnosed to have severe anemia with evidence of occult blood in stool. After initial management, further workup was done to find out the source of bleeding. Upper and lower gastrointestinal endoscopy were normal. Computerized tomography enteroclysis showed no significant abnormality. Later small bowel enteroscopy was performed with the help of Novel Motorized Spiral Enteroscope in antegrade approach and scope passed through oral cavity up to cecum. Multiple angiodysplasia lesions seen in ileum. All the lesions were managed with argon plasma coagulation (APC). Postprocedure, patient improved well and hemoglobin also remained stable. Small bowel diseases always remain a diagnostic and therapeutic challenge, despite the introduction of various modalities for deep enteroscopy. Spiral enteroscopy is a recent advance which uses an overtube with a raised spiral at the distal end to pleat the small intestine. It consumes less time and suits for both diagnostic and therapeutic needs of small bowel diseases.
Common Bile Duct Polyp—Rare But Not So Rare Cause Of Obstructive Jaundice
Authors: Kabrawala Mayank , Desai Pankaj , Mehta Rajiv , Nandwani Subhash , Arora Priya , Patel Chintan , Bhatt Keyur , Mangukiya Dhaval , Parekh Krishna
Published: June 2020

Polyps are usually found in gastrointestinal tract as their primary site of occurrence. In contrast, polyps in common bile duct (CBD) are uncommon. Biliary polyps can manifest as obstructive jaundice, which is the usually a presentation of common bile duct stone or malignant tumor of bile duct and pancreas. In this case series, we present five patients who had clinical manifestations of obstructive jaundice. However, systematic diagnostic approach in these patients revealed presence of polyps in distal CBD. We have focused on diagnostic challenges encountered during the investigation of CBD polyps.
Biodegradable Pancreatic and Biliary Stents—Still Searching For Disappearing Wonder?
Authors: Daniel Philip , Rana Surinder S.
Published: June 2020

Biodegradable stents hold considerable promise in the treatment of benign biliary or pancreatic diseases with the major advantage being avoidance of repeated interventions for stent removal or stent exchange. They have been confirmed to have good biocompatibility and current evidence shows acceptable rates of clinical efficacy and safety. In the current news and views, we discuss an interesting study that has evaluated a new type of biodegradable biliary and pancreatic stent (the Archimedes stent) in benign biliary and pancreatic diseases.
Endoscopic Ultrasound-Guided Transgastric Fine Needle Aspiration of Splenic Metastasis
Authors: Balekuduru Avinash Bhat , Kapali Aravind Subramani , Kurella Suneetha Parandhamaiah , Subbaraj Satyaprakash Bonthala
Published: June 2020

Splenic metastasis is extremely rare and is part of diffuse carcinomatosis. We present a case of a 60-year-old woman with transitional cell ovarian carcinoma who had hysterectomy with bilateral salpingo-oophorectomy in the past. She now presented with solitary splenic metastasis, confirmed by endoscopic ultrasound-guided transgastric fine needle aspiration biopsy.
Improving CAT bond pricing models via machine learning
Authors: Götze Tobias , Gürtler Marc , Witowski Eileen
Published: June 2020

Enhanced machine learning methods provide an encouraging alternative to forecast asset prices by extending or generalizing the possible model specifications compared to conventional linear regression methods. Even if enhanced methods of machine learning in the literature often lead to better forecasting quality, this is not clear for small asset classes, because in small asset classes enhanced machine learning methods may potentially over-fit the in-sample data. Against this background, we compare the forecasting performance of linear regression models and enhanced machine learning methods in the market for catastrophe (CAT) bonds. We use linear regression with variable selection, penalization methods, random forests and neural networks to forecast CAT bond premia. Among the considered models, random forests exhibit the highest forecasting performance, followed by linear regression models and neural networks.
Dynamic in situ X-ray diffraction reveals unexpected intermediate crystal structures
Authors: Patrick Chris
Published: June 2020

Technique allows researchers to see short-lived metal-organic framework structures during dehydration.
Use of alternating magnetic field enables contact-free cell lysis
Authors: Mandel Savannah
Published: June 2020

Researchers perform high-precision cell lysis using an alternating magnetic field and magnetic polymer surface for downstream molecular detection.
Microfluidic enrichment of bacteria coupled to contact-free lysis on a magnetic polymer surface for downstream molecular detection
Authors: Burklund Alison , Petryk James D. , Hoopes P. Jack , Zhang John X. J.
Published: June 2020

We report on a microsystem that couples high-throughput bacterial immunomagnetic capture to contact-free cell lysis using an alternating current magnetic field (AMF) to enable downstream molecular characterization of bacterial nucleic acids. Traditional methods for cell lysis rely on either dilutive chemical methods, expensive biological reagents, or imprecise physical methods. We present a microchip with a magnetic polymer substrate (Mag-Polymer microchip), which enables highly controlled, on-chip heating of biological targets following exposure to an AMF. First, we present a theoretical framework for the quantitation of power generation for single-domain magnetic nanoparticles embedded in a polymer matrix. Next, we demonstrate successful bacterial DNA recovery by coupling (1) high-throughput, sensitive microfluidic immunomagnetic capture of bacteria to (2) on-chip, contact-free bacterial lysis using an AMF. The bacterial capture efficiency exceeded 76% at 50 ml/h at cell loads as low as ∼10 CFU/ml, and intact DNA was successfully recovered at starting bacterial concentrations as low as ∼1000 CFU/ml. Using the presented methodology, cell lysis becomes non-dilutive, temperature is precisely controlled, and potential contamination risks are eliminated. This workflow and substrate modification could be easily integrated in a range of micro-scale diagnostic systems for infectious disease.
Biochemical properties and ultrastructure of mesophyll and bundle sheath thylakoids from maize (Zea mays) chloroplasts
Authors: Aliyeva Nahida K. , Aliyeva Durna R. , Suleymanov Saftar Y. , Rzayev Fuad H. , Gasimov Eldar K. , Huseynova Irada M.
Published: June 2020

A characteristic feature of C4 plants is the differentiation of the photosynthetic leaf tissues into two distinct cell types: mesophyll (M) and bundle sheath (BS) cells. We have investigated several biochemical parameters, including pigment composition, polypeptide patterns, fluorescence at 77K, the activity of photosystems and ultrastructure of mesophyll and bundle sheath chloroplasts of maize (Zea mays L.) plants. It is shown that the BS chloroplasts have ~2-fold higher chlorophyll a/b ratio than M chloroplasts, 6.15 and 3.12 respectively. The PSI apoprotein (68 kDa) was more abundant in BS than in M thylakoids. Polypeptides belonging to PSII core antenna, are in similar amounts in both types of membranes, but the 45kDa band is more intensive in M thylakoids. Polypeptides in the region of 28–24 kDa of the light-harvesting complex of PSII (LHCII) are also present in both types of chloroplasts, though their amounts are reduced in BS thylakoids. The chlorophyll fluorescence emission spectra in M cells showed the presence of three bands at 686, 695 and 735 nm characteristics of LHCII, PSII core and PSI complexes, respectively. However, in the fluorescence spectrum of agranal plastids, there are almost traces of the band at 695 nm, which belongs to the PSII core complex. The research results revealed that the photochemical activity of PSII in BS chloroplasts is ~5 times less than in the chloroplasts of M cells. The highest PSI activity was found in maize BS chloroplasts.
Glutamate and NMDA affect cell excitability and action potential dynamics of single cell of macrophyte Nitellopsis obtusa
Authors: Lapeikaite Indre , Pupkis Vilmantas , Neniskis Vladas , Ruksenas Osvaldas , Kisnieriene Vilma
Published: June 2020

The effect of glutamate and N-methyl-d-aspartate (NMDA) on electrical signalling – action potentials (AP) and excitation current transients – was studied in intact macrophyte Nitellopsis obtusa (Characeaen) internodal cell. Intracellular glass electrode recordings of single cell in current clamp and two-electrode voltage clamp modes indicate that glutamate (Glu, 0.1–1.0 mM) and NMDA (0.01–1.0 mM) increase electrically induced AP amplitude by hyperpolarising excitation threshold potential (Eth) and prolong AP fast repolarisation phase. Amplitude of Cl– current transient, as well as its activation and inactivation durations were also increased. Both Glu and NMDA act in a dose-dependent manner. The effect of NMDA exceeds that of Glu. Ionotropic glutamate receptor inhibitors AP-5 (NMDA-type receptors) and DNQX (AMPA/Kainate-type) have no effect on Nitellopsis cell electrical signalling per se, yet robustly inhibit excitatory effect of NMDA. This study reinforces NMDA as an active component in glutamatergic signalling at least in some plants and stresses the elaborate fine-tuning of electrical signalling.
Up-regulated cytotrophoblast DOCK4 contributes to over-invasion in placenta accreta spectrum
Authors: McNally Leah , Zhou Yan , Robinson Joshua F. , Zhao Guangfeng , Chen Lee-may , Chen Hao , Kim M. Yvonne , Kapidzic Mirhan , Gormley Matthew , Hannibal Roberta , Fisher Susan J.
Published: June 2020

Significance

The syndrome of cytotrophoblast invasion beyond the normal boundary (in the superficial myometrium) is collectively termed placenta accreta spectrum. The incidence of this condition is rising. However, little is known about the underlying molecular changes. Global transcriptomic profiling of cytotrophoblasts isolated from these cases, as compared to gestational age-matched controls, revealed numerous changes in gene expression involving diverse pathways, including cell signaling, migration, and immune functions.
DOCK4
was the most highly up-regulated mRNA in the cases. Mutations in this gene are mechanistically linked to cancer progression. Overexpression of DOCK4 in primary cytotrophoblasts increased their invasiveness. This study provides molecular insights into the pathways driving placenta accreta spectrum and suggests numerous future directions.
A combined activation mechanism for the glucagon receptor
Authors: Mattedi Giulio , Acosta-Gutiérrez Silvia , Clark Timothy , Gervasio Francesco Luigi
Published: June 2020

Significance

Understanding the mechanisms of activation of G-protein–coupled receptors (GPCRs) is a major issue in biophysics and pharmacology. This is particularly true for peptide-activated class B receptors, which are more flexible and have been studied less than class A. Here, we combine simulations and free-energy landscape calculations to study the activation mechanism of the glucagon receptor, a prototypical class B GPCR. In contrast to previous conformational selection hypotheses, we find that both interactions with the peptide and the G protein are necessary to induce the transition to the active state. The results of this study not only contribute to a better understanding of GPCR activation mechanisms but will also aid in the future development of drugs targeting the glucagon receptor.
Extreme climate after massive eruption of Alaska’s Okmok volcano in 43 BCE and effects on the late Roman Republic and Ptolemaic Kingdom
Authors: McConnell Joseph R. , Sigl Michael , Plunkett Gill , Burke Andrea , Kim Woon Mi , Raible Christoph C. , Wilson Andrew I. , Manning Joseph G. , Ludlow Francis , Chellman Nathan J. , Innes Helen M. , Yang Zhen , Larsen Jessica F. , Schaefer Janet R. , Kipfstuhl Sepp , Mojtabavi Seyedhamidreza , Wilhelms Frank , Opel Thomas , Meyer Hanno , Steffensen Jørgen Peder
Published: June 2020

Significance

The first century BCE fall of the Roman Republic and Ptolemaic Kingdom and subsequent rise of the Roman Empire were among the most important political transitions in the history of Western civilization. Volcanic fallout in well-dated Arctic ice core records, climate proxies, and Earth system modeling show that this transition occurred during an extreme cold period resulting from a massive eruption of Alaska’s Okmok volcano early in 43 BCE. Written sources describe unusual climate, crop failures, famine, disease, and unrest in the Mediterranean immediately following the eruption—suggesting significant vulnerability to hydroclimatic shocks in otherwise sophisticated and powerful ancient states. Such shocks must be seen as having played a role in the historical developments for which the period is famed.