bluuebunny/crossref_metadata_2025 huggingface dataset:
CT images with expert manual contours of thoracic cancer for benchmarking auto‐segmentation accuracy
Authors: Yang Jinzhong , Veeraraghavan Harini , van Elmpt Wouter , Dekker Andre , Gooding Mark , Sharp Greg
Published: March 2020

Purpose

Automatic segmentation offers many benefits for radiotherapy treatment planning; however, the lack of publicly available benchmark datasets limits the clinical use of automatic segmentation. In this work, we present a well‐curated computed tomography (CT) dataset of high‐quality manually drawn contours from patients with thoracic cancer that can be used to evaluate the accuracy of thoracic normal tissue auto‐segmentation systems.

Acquisition and validation methods

Computed tomography scans of 60 patients undergoing treatment simulation for thoracic radiotherapy were acquired from three institutions: MD Anderson Cancer Center, Memorial Sloan Kettering Cancer Center, and the MAASTRO clinic. Each institution provided CT scans from 20 patients, including mean intensity projection four‐dimensional CT (4D CT), exhale phase (4D CT), or free‐breathing CT scans depending on their clinical practice. All CT scans covered the entire thoracic region with a 50‐cm field of view and slice spacing of 1, 2.5, or 3 mm. Manual contours of left/right lungs, esophagus, heart, and spinal cord were retrieved from the clinical treatment plans. These contours were checked for quality and edited if necessary to ensure adherence to RTOG 1106 contouring guidelines.

Data format and usage notes

The CT images and RTSTRUCT files are available in DICOM format. The regions of interest were named according to the nomenclature recommended by American Association of Physicists in Medicine Task Group 263 as Lung_L, Lung_R, Esophagus, Heart, and SpinalCord. This dataset is available on The Cancer Imaging Archive (funded by the National Cancer Institute) under Lung CT Segmentation Challenge 2017 (http://doi.org/10.7937/K9/TCIA.2017.3r3fvz08).

Potential applications

This dataset provides CT scans with well‐delineated manually drawn contours from patients with thoracic cancer that can be used to evaluate auto‐segmentation systems. Additional anatomies could be supplied in the future to enhance the existing library of contours.
Evaluation of admittance control as an alternative to passive arm supports to increase upper extremity function for individuals with Duchenne muscular dystrophy
Authors: Corrigan Madeline C. , Foulds Richard A.
Published: March 2020

The degree of upper extremity active range of motion provided by an admittance control robot compared with a commercially available passive arm support for individuals with DMD who have limited arm function was investigated in this study. The reachable workspace evaluation was used to assess active range of motion provided by both devices. A visual analog scale was also used to secure participant‐reported outcome measures. The admittance control robot significantly increased reachable surface area scores compared with the passive arm support for the dominant arm (Wilcoxon T = 5, P = .022, r2 = 0.263) and for the nondominant arm (paired‐samples t test, t(9) = 4.66, P = .001, r2 = 0.71). The admittance control robot also significantly decreased participant‐reported exertion compared with the passive arm support. Results of this study substantiated the benefits of admittance control for individuals with DMD compared with a commercially available passive arm support.
EF hand‐like motif mutations of Nav1.4 C‐terminus cause myotonic syndrome by impairing fast inactivation
Authors: Horie Riho , Kubota Tomoya , Koh Jinsoo , Tanaka Rieko , Nakamura Yuichiro , Sasaki Ryogen , Ito Hidefumi , Takahashi Masanori P.
Published: March 2020

Introduction

Mutations of the voltage‐gated sodium channel gene (SCN4A), which encodes Nav1.4, cause nondystrophic myotonia that occasionally is associated with severe apnea and laryngospasm. There are case reports of nondystrophic myotonia due to mutations in the C‐terminal tail (CTerm) of Nav1.4, but the functional analysis is scarce.

Methods

We present two families with nondystrophic myotonia harboring a novel heterozygous mutation (E1702del) and a known heterozygous mutation (E1702K).

Results

The proband with E1702K exhibited repeated rhabdomyolysis, and the daughter showed laryngospasm and cyanosis. Functional analysis of the two mutations as well as another known heterozygous mutation (T1700_E1703del), all located on EF hand‐like motif in CTerm, was conducted with whole‐cell recording of heterologously expressed channel. All mutations displayed impaired fast inactivation.

Discussion

The CTerm of Nav1.4 is vital for regulating fast inactivation. The study highlights the importance of accumulating pathological mutations of Nav1.4 and their functional analysis data.
India and the US as enduring global partners: An assessment
Authors: Ahmad Riaz , Gul Azeem , Khan Muhammad Mussa
Published: March 2020

This paper examines the nature of India and the US relations. The relations between two the states have improved in the post−/11 era. The willingness of the US to provide India political support at the regional and global level is one aspect that resulted in changing the nature of that relationship. Second, growing defense ties both in conventional and nonconventional sectors fundamentally galvanized the nature of that relationship. This paper further analyzes the geopolitical compulsion of both states to counter various state and non‐state actors' threats such as China's increasing maritime presence in the Indian Ocean region and terrorism. Moreover, this discussion argues about the political, strategic, commercial aspects of the strategic partnership till date. Much part of this paper analyzes what is the nature of this relationship and how it developed?
Synthesis of millimeter‐sized hydrogel beads by inverse Pickering polymerization using starch‐based nanoparticles as emulsifier
Authors: Zhai Kankan , Zhang Fan , Wang Chao , Pei Xiaopeng , Tan Ying , Bai Yungang , Zhang Baichao , Wang Yinchuan , Xu Kun , Wang Pixin
Published: March 2020

The preparation of millimeter‐sized poly(acrylamide‐co‐acrylic acid) hydrogel beads via inverse Pickering emulsion polymerization using starch‐based nanoparticles (SNPs) as stabilizers is reported. Amphiphilic starch is fabricated by the introduction of butyl glycidyl ether groups and palmitate groups, and the hydrophobically modified SNPs are fabricated by a nanoprecipitation process. The obtained SNPs could adsorb at oil‐water interfaces to stabilize an inverse Pickering emulsion, and the effects of oil/water volume fraction ratio and SNP concentration on emulsions are comprehensively studied. Poly(acrylamide‐co‐acrylic acid) hydrogel beads with a size of approximately 1 mm are obtained by inverse Pickering emulsion polymerization stabilized by SNPs. The morphology and structure of hydrogel beads are extensively investigated, which confirms that SNPs locate on the surface of hydrogel beads and act as emulsifiers and network structures present inside the beads. Polymerization is also detected to investigate the potential formation mechanism of hydrogel beads. The pH‐responsive property of hydrogel beads and its potential application for drug delivery are also explored.
An integrated strategy for holistic quality identification of Chinese patent medicine: Liuwei Dihuang Pills as a case study
Authors: Wang Xia , Wu Wenyong , Zhang Jianqing , Gao Lei , Zhang Linlin , Long Huali , Hou Jinjun , Wu Wanying , Guo Dean
Published: March 2020

Introduction

Liuwei Dihuang Pills (concentrated pills, simplified as LWDHP), one of the most famous classic Chinese Patent Medicine (CPM), is produced by hundreds of pharmaceutical manufacturers with billions of Chinese yuan (CNY) in annual sales. However, current quality identification of LWDHP mainly relies on a thin‐layer chromatography (TLC) method that is complicated and deficient.

Objective

The goal of this study is to simplify the identification process and provide a more comprehensive quality assessment method of LWDHP by developing an integrated strategy based on liquid chromatography coupled with mass spectrometry (LC‐MS) and multivariate statistical analysis.

Method

Ultra‐high‐performance liquid chromatography coupled with quadrupole‐time of flight mass spectrometry (UHPLC/QTOF‐MS) was employed to perform qualitative analyses of a home‐made LWDHP and to establish a stably characteristic compound library by analysis of batches of its component herbs. Then selective ion monitoring (SIM) of single MS was utilised to develop a rapid identification method based on the UHPLC/QTOF‐MS analysis result. Multivariate statistical analysis was subsequently used for the quality assessment of different commercial samples.

Results

Seventy‐eight characteristic compounds were characterised, and 68 of them were recorded to establish a stably characteristic compound library. Thirty‐one compounds were selected from the library for the establishment of SIM identification method. Good specificity, capability, and feasibility had been respectively verified by the analysis of blank sample, negative control (NC) preparation samples, home‐made LWDHP sample, and commercial sample. Multivariate statistical analysis of 20 batches of commercial LWDHP samples revealed the quality consistency of the same vendor's product and quality difference between diverse vendors' products.

Conclusion

The SIM identification method by a single analysis could significantly simplify the identification process of LWDHP, and it was performed in a holistic mode for no less than two compounds of each component herb monitored. Moreover, it could also be combined with multivariate statistical analysis to conduct quality assessments of batches of samples. The integrated strategy used in the study of LWDHP could be applied for the identification of other CPM as well.
Descriptive analysis of postmarket surveillance data for hip implants
Authors: Pane Josep , Verhamme Katia M. C. , Rebollo Irene , Sturkenboom Miriam C. J. M.
Published: March 2020

Purpose

Recent safety issues involving medical devices have highlighted the need for better postmarket surveillance (PMS) evaluation. This article aims to describe and to assess the quality of the PMS data for a medical device and, finally, to provide recommendations to improve the data gathering process.

Methods

A descriptive analysis of medical device reports (MDRs) on the use of MRA, a specific type of hip implant replacement submitted to the Food and Drug Administration Manufacturer and User Facility Device Experience database from 1 January 2008 to 31 December 2017. The number of reports was described as the number of MDRs per unique MDR number and stratified by different variables. The quality was assessed by the level of completeness of the collected PMS data.

Results

The total number of reports related to MRA was 2377, and the number of MDRs per year ranged between 84 in 2009 and 452 in 2017. Most of the reports were reported by manufacturer Depuy Johnson & Johnson and were reported by a physician. In 44.9% of the reports, the device problem was reported as “Unknown.” When the device problem was known, in the majority of cases, it was related to an implant fracture. The quality of the collected data was assessed as low due to missing information.

Conclusion

The underlying data should meet high quality standards to generate more evidence and to ensure a timely signal generation. This case study shows that the completeness and quality of the MDRs can be improved. The authors propose the development of tools to ensure a more dynamic complaint data collection to contribute to this enhancement.
Taliks, cryopegs, and permafrost dynamics related to channel migration, Colville River Delta, Alaska
Authors: Stephani Eva , Drage Jeremiah , Miller Duane , Jones Benjamin M. , Kanevskiy Mikhail
Published: March 2020

Talik and cryopeg development related to channel migration has been observed in arctic deltas, but our knowledge on the configuration, properties, and rate of freezeback has remained limited. Along a main channel of the Colville River Delta (Alaska), we integrated subsurface data from 79 boreholes with a remote sensing analysis to measure channel changes in 1948–2013. We found that closed taliks occurred under the active channel and extended into intrapermafrost cryopeg layers under the riverbed/riverbar and active floodplain. Cryopegs as isolated small pockets were also identified at depths in older terrain units. In the study corridor, we estimated that the likelihood of talik and cryopeg occurrence was predominantly (42.2% of area) low, yet a high likelihood was also identified (27.0% of area). Permafrost growth occurred at a rapid rate in the land exposed following channel migration, likely due to the low and delayed release of latent heat as the freezing front progresses downward in the coarse‐grained soils of increasing salinity but decreasing temperatures. As the deposits keep cooling, ground ice will continue forming therefore increasing furthermore the salinity of the remaining unfrozen soil pore‐water and likely prevent the complete freezeback of the cryopegs developed in relation to channel migration.
Proteomic and Transcriptomic Approaches for Studying Bone Regeneration in Health and Systemically Compromised Conditions
Authors: Calciolari Elena , Donos Nikolaos
Published: March 2020

Bone regeneration is a complex biological process, where the molecular mechanisms are only partially understood. In an ageing population, where the prevalence of chronic diseases with an impact on bone metabolism is increasing, it becomes crucial to identify new strategies that would improve regenerative outcomes also in medically compromised patients. In this context, omics are demonstrating a great potential, as they offer new insights on the molecular mechanisms regulating physiologic/pathologic bone healing and, at the same time, allow the identification of new diagnostic and therapeutic targets. This review provides an overview on the current evidence on the use of transcriptomic and proteomic approaches in bone regeneration research, particularly in relation to type 1 diabetes and osteoporosis, and discusses future scenarios and potential benefits and limitations on the integration of multi‐omics. It is suggested that future research will leverage the synergy of omics with statistical modeling and bioinformatics to prompt the understanding of the biology underpinning bone formation in health and medically compromised conditions. With an eye toward personalized medicine, new strategies combining the mining of large datasets and bioinformatic data with a detailed characterization of relevant phenotypes will need to be pursued to further the understanding of disease mechanisms.
Quantification of pesticide residues in the topsoil of Belgian fruit orchards: terrestrial environmental risk assessment
Authors: Claus Gregor , Spanoghe Pieter
Published: March 2020

BACKGROUND

Pesticides are widely used in fruit orchards. In the context of integrated pest management (IPM) Flemish farmers are advised to restrict the use of pesticides. However, pesticide residues could still pose a threat to beneficial organisms. To date, it is not well known which residues are present in IPM orchards. This study focuses on the pesticide concentration in the topsoil and the implications for soil‐dwelling organisms.

RESULTS

Topsoil was sampled in ten sweet cherry (Prunus avium (L.) L.) and eight apple (Malus domestica Borkh.) orchards in Flanders (Belgium), to quantify the concentration of pesticide residues. Topsoil was selected because it is a major exposure route for beneficials. Both pesticides from both current spraying schedules and those used previously were found. In addition, an environmental risk assessment was performed using species sensitivity distribution (SSD) and toxicity/exposure ratio (TER) approaches. The SSD approach led to a more conservative outcome. None of the pesticides in the spraying schedule revealed a risk, although some of the persistent and banned pesticides may continue to do so.

CONCLUSION

Spraying schedules are good predictors of environmental contamination. Monitoring of residues remains essential to determine the real residue concentration in the topsoil. SSDs proved valuable. It was inferred that in addition to the standard test with the earthworm Eisenia fetida (Savigny, 1826), an arthropod test organism such as Folsomia candida (Willem, 1902) should be used in future risk assessments because it displays higher sensitivity towards insecticides.
Nodal Semimetals: A Survey on Optical Conductivity
Authors: Pronin Artem V. , Dressel Martin
Published: March 2020

Among different topological and related phases of condensed matter, nodal semimetals occupy a special place—the electronic band topology in these materials is related to 3D bulk, rather than to surface, states. A great variety of different realizations of electronic band crossings (the nodes) leads to a plethora of different electronic properties, ranging from chiral anomaly to solid‐state realizations of a black‐hole horizon. The different nodal phases have similar low‐energy band structure and quasiparticle dynamics, which both can be accessed experimentally by a number of methods. Optical measurements with their large penetration depth and high energy resolution are ideally suited as such a bulk probe, especially at low energies where other spectroscopic methods often lack the required resolution. Herein, recent optical conductivity studies of different nodal semimetals are reviewed, possible limitations of such measurements are discussed, and a comparison between the experimental results, simple theoretical models, and band‐structure‐based calculations is provided.
A family of virtual contraction based controllers for tracking of flexible‐joints port‐Hamiltonian robots: Theory and experiments
Authors: Reyes‐Báez Rodolfo , van der Schaft Arjan , Jayawardhana Bayu , Pan Le
Published: March 2020

In this work, we present a constructive method to design a family of virtual contraction based controllers that solve the standard trajectory tracking problem of flexible‐joint robots in the port‐Hamiltonian framework. The proposed design method, called virtual contraction based control, combines the concepts of virtual control systems and contraction analysis. It is shown that under potential energy matching conditions, the closed‐loop virtual system is contractive and exponential convergence to a predefined trajectory is guaranteed. Moreover, the closed‐loop virtual system exhibits properties such as structure preservation, differential passivity, and the existence of (incrementally) passive maps. The method is later applied to a planar RR robot, and two nonlinear tracking control schemes in the developed controllers family are designed using different contraction analysis approaches. Experiments confirm the theoretical results for each controller.
Synthesis of Fused Indolo‐Pyrazoles and Their Antimicrobial and Insecticidal Activities against Anopheles arabiensis Mosquito
Authors: Makhanya Talent R. , Gengan Robert M. , Kasumbwe Kabange
Published: March 2020

A new approach was used for the synthesis of novel fused indolo‐pyrazoles (FIPs). Indole, arylhydrazine and benzaldehyde derivatives were used for the [3+2] annulation reaction in one‐pot system. The compounds were characterised by 1H NMR, 13C NMR, 2D NMR, MS and elemental analysis. The in vitro antifungal activity of the FIPs were evaluated against Candida albicans, Candida utilis, Saccharomyces cerevisiae, Aspergillus flavus and Aspergillus niger. Two FIPs, viz. N‐methyl‐3‐phenyl‐2, 3‐dihydropyrazolo [3, 4‐b] indole‐1(4H)‐carbothioamide (8 r) and 3‐(4‐methoxyphenyl)‐N‐methyl‐2,3‐dihydropyrazolo[3,4‐b]indole‐1(4H)‐carbothioamide (8 x) displayed good antifungal activity against Saccharomyces cerevisiae with a zone of inhibition diameter of 23 and 20 mm, respectively. They also displayed substantial potency against Saccharomyces cerevisiae with the MIC of 0.18 μM. All FIPs were screened for larvicidal and insecticidal properties against Anopheles arabiensis of which 12 FIPs produced more than 80 % larvae mortality at a 4 μg/mL dose in 24 hours whilst 8 FIPs showed a knock‐down of mosquitoes within the first 60 minutes of exposure, which was comparable to the positive control Temephos.
A Technical Introduction to Transmission Electron Microscopy for Soft‐Matter: Imaging, Possibilities, Choices, and Technical Developments
Authors: Franken Linda E. , Grünewald Kay , Boekema Egbert J. , Stuart Marc C. A.
Published: March 2020

With a significant role in material sciences, physics, (soft matter) chemistry, and biology, the transmission electron microscope is one of the most widely applied structural analysis tool to date. It has the power to visualize almost everything from the micrometer to the angstrom scale. Technical developments keep opening doors to new fields of research by improving aspects such as sample preservation, detector performance, computational power, and workflow automation. For more than half a century, and continuing into the future, electron microscopy has been, and is, a cornerstone methodology in science. Herein, the technical considerations of imaging with electrons in terms of optics, technology, samples and processing, and targeted soft materials are summarized. Furthermore, recent advances and their potential for application to soft matter chemistry are highlighted.
Cu/ZnO Catalysts Derived from Bimetallic Metal–Organic Framework for Dimethyl Ether Synthesis from Syngas with Enhanced Selectivity and Stability
Authors: Li Fuping , Ao Min , Pham Gia Hung , Sunarso Jaka , Chen Yanping , Liu Jian , Wang Kai , Liu Shaomin
Published: March 2020

Direct conversion of syngas to dimethyl ether (DME) through the intermediate of methanol allows more efficient DME production in a simpler reactor design relative to the conventional indirect route. Although Cu/ZnO‐based multicomponent catalysts are highly active for methanol synthesis in this process, the sintering issue of Cu during the prolonged reaction generally deteriorates their performance. In this work, Cu/ZnO catalysts in a novel octahedron structure are prepared by a two‐step pyrolysis of Zn‐doped Cu‐BTC metal–organic framework (MOF) in N2 and air. The catalyst CZ‐350/A, hybrid of MOF‐derived Cu/ZnO sample CZ‐350 and γ‐Al2O3 for methanol dehydration, displays the best activity for DME formation (7.74% CO conversion and 70.05% DME selectivity) with the lowest deterioration rate over 40 h continuous reaction. Such performance is superior to its counterpart CZ‐CP/A made via the conventional coprecipitation method. This is mainly due to the confinement of Cu nanoparticles within the octahedron matrix hindering their migration and aggregation. Besides, partial reduction of ZnO in the activated CZ‐350 prompts the formation of Cu+‐O‐Zn, further facilitating the DME production with the highest selectivity compared to literature results. The results clearly indicate that Cu and ZnO distribution in the catalyst architecture plays an important role in DME formation.
Preparation of novel and durable concrete skin
Authors: Shi Yong , Shi ZhiMing
Published: March 2020

The performance of the conventional concrete skin was promoted by ultrasonic surface treatment (UST) in this study, and the newly formed dense and hard concrete skin was termed as ultrasonic hardening layer (UHL). The microstructure of UHL was scanned and analyzed, several durability‐related indicators, such as water vapor penetration rate, surface, and interface hardness, were measured, and it was found that UHL could effectively improve the durability of concretes. The light reflectance of the UHL concrete surface was measured in the spectrum range of UV (200 nm) to NIR (2,500 nm), and it manifested 24.17% less mean reflectance than the conventional concrete skin. Therefore, UHL could serve as a promising road material due to its better melting capacity in cold‐temperate zones.
Joint behavior and design procedure of a through plate connection for steel beam to hollow or concrete‐filled tubular columns
Authors: Ahmadi Mohammad Mehdi , Mirghaderi Seyed Rasoul
Published: March 2020

The through plate connection has a practical reliable configuration for fully restrained connections for a steel I‐beam to hollow or concrete‐filled tubular columns in seismic areas. Based on experimental programs of authors on interior planar moment connections via through plate technique, this paper presents the outcome of the studies focusing on the joint behavior and the shear transfer in the panel zone of through plate connection. Based on the conducted approved three full‐scale tests, the behavior of connection components and panel zone shear force were investigated accurately in order to provide useful information and key parameters to facilitate design calculations and proportioning the connection. The contribution of each component in the total shear capacity of the panel zone region was determined. Load transfer mechanisms were explained and by quantifying the portion of load transfer paths, the calculation approach was described for design purpose. The proposed design procedure was validated for a wide range of beam to column connections using finite element models. Verified numerical models were used to conduct parametric studies. The numerical results revealed that the proposed analysis method can predict well the induced demand in the connection components and also the design procedure is suitable and secure for all cases.
Testing use of a potential cognitive enrichment device by an Indo‐Pacific bottlenose dolphin (Tursiops aduncus)
Authors: Matrai Eszter , Ng Angela K. W. , Chan Michelle M. H. , Gendron Suzanne M. , Dudzinski Kathleen M.
Published: March 2020

Cognitive enrichment aims to provide animals with opportunities to use their cognitive skills and to promote behaviors associated with positive wellbeing. Cooperation in mammals has been recorded during various behavioral contexts such as hunting, mating, playing, and parental care. Coordinated activity, often with some level of problem‐solving action included, is required during cooperation. To investigate dolphins’ ability for collaborative problem‐solving, an enrichment device was introduced to two adult male Indo‐Pacific bottlenose dolphins (Tursiops aduncus). The device contained fish and ice and was designed to be opened by simultaneously pulling on both ends. After repeated presentation, it became apparent that only one dolphin had active interest in the device. To facilitate opportunities for problem‐solving by this individual, an alternative collaborator, a human partner, was provided. Still, both dolphins had access to the device throughout the entire experiment. After the first opening, the same dolphin was highly successful in collaborating with the human in both joined (93%) and delayed (100%) partner conditions. The device provided a novel opportunity for the dolphin to use his cognitive skills. Even though only one dolphin participated actively, both dolphins showed varying degrees of interest to the device throughout the study. Both dolphins spent an average of 48% and 16% of their time, respectively, with the device, which resulted in a significant decrease in their other two most frequently observed behaviors: swimming and poolside observation. As a novel cognitive challenge, the device may be considered as a type of cognitive enrichment.
Special holonomy manifolds, domain walls, intersecting branes and T-folds
Authors: Chaemjumrus N. , Hull C.M.
Published: March 2020

Abstract

We discuss the special holonomy metrics of Gibbons, Lu, Pope and Stelle, which were constructed as nilmanifold bundles over a line by uplifting supersymmetric domain wall solutions of supergravity to 11 dimensions. We show that these are dual to intersecting brane solutions, and considering these leads us to a more general class of special holonomy metrics. Further dualities relate these to non-geometric backgrounds involving intersections of branes and exotic branes. We discuss the possibility of resolving these spaces to give smooth special holonomy manifolds.
Tradition vs. Moderne: Möglichkeiten und Limitationen eines neuen Vorlesungskonzepts in der curricularen HNO-Lehre
Authors: Daubenfeld T. , Kromeier J. , Heermann S. , Hildenbrand T. , Giesler M. , Offergeld C.
Published: March 2020

Hintergrund

Wegen stetig schwindender Präsenz Studierender wurde an der Univ.-HNO-Klinik Freiburg im Wintersemester (WS) 2017/18 ein neuartiges Blended-Learning-Vorlesungsformat gestartet: die HNO-3-D-Reihe. Um komplexe HNO-Themen (z. B. Mittelohr) verständlicher, ansprechender und klinisch relevanter zu präsentieren, kooperierten die klinischen Fachgebiete HNO-Heilkunde und Radiologie mit dem vorklinischen Fachgebiet Anatomie. Ziel der Studie war es, dieses Lehrformat zu evaluieren und Präferenzen zu ermitteln, welche Studierende zum Vorlesungsbesuch animieren könnten.

Methoden

Teilnehmende des HNO-Blockpraktikums im WS 2017/18 wurden in allen Vorlesungen mithilfe einer Evaluationskarte zur Qualität der Vorlesung befragt. Zudem wurde in jeder der neukonzipierten Vorlesungen der Wissenszuwachs überprüft. Mit einem Abschlussfragebogen wurden Präferenzen bei den Lehrmethoden erfragt.

Ergebnisse

Insgesamt wurden die neuen Lehrangebote nicht besser benotet als die regulären, aber das neue Konzept grundsätzlich als positiv bewertet. Es gelang nicht, mehr Vorlesungsteilnehmende zu gewinnen. Das traditionelle Lehrformat „Vorlesung“ wird von einer umschriebenen Gruppe von Studierenden weiterhin als zeitgemäß angesehen.

Schlussfolgerungen

Bei prinzipiell positiver studentischer Bewertung eines neuen Vorlesungsformats erreichten die 3‑D-Vorlesungen in keiner der Kategorien Bestwerte. Dies erklärt sich aus der Häufung unerwarteter studentischer Kritikpunkte (Quantität des Lehrinhalts). Somit konnten die als Gradmesser vorgesehenen Parameter (E-Learning, Qualität der Lehrveranstaltung, Einsatz moderner Lehrmethoden) ihre Aufgabe nicht erfüllen. Das Evaluationsergebnis erfordert eine kritische Reflexion und ggf. partielle Umorganisation der Lehrveranstaltung (inhaltliche Verschlankung).
Die Weiterbildungssituation in der HNO-Heilkunde in Deutschland
Authors: Linke J. , Eichhorn T. , Kemper M. , Zahnert T. , Neudert M.
Published: March 2020

Hintergrund

Als Ansatzpunkt zur Entwicklung konkreter Optimierungsvorschläge für das HNO-ärztliche Weiterbildungssystem wurde zunächst die Ausbildungssituation an deutschen HNO-Kliniken analysiert, um existierende Schwachstellen der Weiterbildung identifizieren zu können.

Methodik

HNO-Weiterbildungsassistenten an deutschen HNO-Kliniken wurden eingeladen, an einer Online-Befragung teilzunehmen. Der Fragebogen bestand dabei aus 78 Einzelfragen.

Ergebnisse

An der Umfrage nahmen 223 Weiterbildungsassistenten der HNO-Heilkunde teil. Defizite der Ausbildung wie ein fehlendes regelmäßiges Feedback zwischen Weiterbildungsberechtigten und Weiterbildungsassistenten/-innen, eine nur mittelmäßig bewertete Vermittlung von Fachkompetenz sowie eine in den Freitextkommentaren genannte „Willkür“ der Weiterbildungsbeauftragten hinsichtlich der Gestaltung des Weiterbildungsverlaufs sowie Zeit- und Personalmangel treten in den Fokus unserer Auswertung. Einige der verbindlich aufgeführten Empfehlungen der Weiterbildungsordnung wie die Festlegung von konkreten Weiterbildungszielen im Rahmen eines regelmäßigen Gesprächs oder der Einsatz eines Log-Buchs werden bislang nur vereinzelt umgesetzt. Forderungen zum Ausbau von externen Fortbildungsmöglichkeiten (Hospitation/Rotation) und einer externen objektiven Überprüfung der klinikinternen Durchführung der Weiterbildung im Sinne einer Qualitätssicherung beispielsweise durch Fachvertreter der Deutschen Gesellschaft für HNO-Heilkunde, Kopf- und Halschirurgie (DGHNOKHC) werden diskutiert.

Schlussfolgerung

Die Umsetzung einer strukturierten und standardisierten Weiterbildung in Deutschland, welche im Sinne einer freiwilligen Eigeninitiative auch durch die DGHNOKHC in ihrer Umsetzung überprüft wird, kann eine Basis für eine effektivere verbindliche Weiterbildung schaffen.
The influence of rhythm on detection of auditory and vibrotactile asynchrony
Authors: Lauzon Andrew P. , Russo Frank A. , Harris Laurence R.
Published: March 2020

The perception of an event is strongly influenced by the context in which it occurs. Here, we examined the effect of a rhythmic context on detection of asynchrony in both the auditory and vibrotactile modalities. Using the method of constant stimuli and a two-alternative forced choice (2AFC), participants were presented with pairs of pure tones played either simultaneously or with various levels of stimulus onset asynchrony (SOA). Target stimuli in both modalities were nested within either: (i) a regularly occurring, predictable rhythm (ii) an irregular, unpredictable rhythm, or (iii) no rhythm at all. Vibrotactile asynchrony detection had higher thresholds and showed greater variability than auditory asynchrony detection in general. Asynchrony detection thresholds for auditory targets but not vibrotactile targets were significantly reduced when the target stimulus was embedded in a regular rhythm as compared to no rhythm. Embedding within an irregular rhythm produced no such improvement. The observed modality asymmetries are interpreted with regard to the superior temporal resolution of the auditory system and specialized brain circuitry supporting auditory–motor coupling.
Diltiazem Prophylaxis for the Prevention of Atrial Fibrillation in Patients Undergoing Thoracoabdominal Esophagectomy: A Retrospective Cohort Study
Authors: Hochreiter Marcel , Schmidt Thomas , Siegler Benedikt H. , Sisic Leila , Schmidt Karsten , Bruckner Thomas , Müller‐Stich Beat P. , Diener Markus K. , Weigand Markus A. , Büchler Markus W. , Busch Cornelius J.
Published: March 2020

Background

Atrial fibrillation (AF) represents the most frequent arrhythmic disorder after thoracoabdominal esophageal resection and is associated with a significant increase in perioperative morbidity and mortality.

Methods

In this retrospective cohort study, 167 patients who underwent thoracoabdominal esophagectomy at a large university hospital were assessed. We compared patients who received a 14‐day postoperative course of diltiazem with a control group of patients who did not undergo diltiazem prophylaxis. Diltiazem therapy started immediately upon admission to the intensive care unit (ICU) with a loading dose of 0.25 mg/kg bodyweight (i.v.) followed by continuous infusion (0.1 mg/kg bodyweight/h) for 40–48 h. Oral administration (Dilzem® 180 mg uno retard, once a day) was started on postoperative day 3.

Results

A total of 117 patients were assessed. Twelve (10.3%) of all patients developed postoperative new‐onset atrial fibrillation in the first 30 days after surgical intervention. Prevalence of new‐onset AF showed no significant differences between the diltiazem group and control group (p = 0.74). The prevalence of bradycardia (14.7% vs. 3.6%; p = 0.03) and dose of norepinephrine required (0.09 vs. 0.04 µg/kg bodyweight/min; p = 0.04) were higher in the diltiazem group. There were no significant differences between the groups for the median postoperative duration of hospital/ICU stay or mortality.

Conclusions

A prophylactic 14‐day postoperative course of diltiazem was not associated with a reduction in new‐onset AF or 30‐day mortality following thoracoabdominal esophagectomy. Prophylactic diltiazem therapy was associated with drug‐related adverse effects such as bradycardia and increased requirement of norepinephrine.

German Clinical Trial Registration Number: DKRS00016631.
Surgeon Experience with Parental Leave Policies Varies Based on Practice Setting
Authors: Bingmer Katherine , Walsh Danielle S. , Gantt Nancy L. , Sanfey Hilary A. , Stein Sharon L.
Published: March 2020

Background

The increase in female surgeons has resulted in scrutiny of widely variable parental leave policies. We hypothesized that academic and private practice surgeons have different experiences based on difference in workplace expectations.

Methods

A 25‐question survey was disseminated via social media and through the Association of Women Surgeons social media platforms from June 1 to September 15, 2017. An analysis of attending surgeons working in the USA in an academic or private practice setting was performed.

Results

Of 1115 total respondents, 477 were attending surgeons practicing in the USA. Practice distribution was 34% private and 47% academic. There was no difference in marital status, work status, or the number who report having been pregnant between the groups. Compared to academic surgeons, private practice surgeons were statistically less likely to have paid leave (p < 0.001) and were more likely to continue to pay benefits while on leave (p < 0.001). Private practitioners were more likely to return to work sooner than desired due to financial (p = 0.022) and supervisor (p = 0.004) pressures and were more likely to leave a job (p = 0.01). Academic surgeons were more likely to experience a delay in job advancement (p = 0.031). On multivariate analysis, more than two pregnancies were associated with an increased risk of perception of a bias and discrimination against pregnancy in the workplace.

Conclusions

Parental leave policies and attitudes vary between academic and private practice, creating unique challenges for female surgeons and different issues for family planning depending on employment model.
XUV laser mass spectrometry for nano-scale 3D elemental profiling of functional thin films
Authors: Bleiner D. , Trottmann M. , Cabas-Vidani A. , Wichser A. , Romanyuk Y. E. , Tiwari A. N.
Published: March 2020

Direct nano-scale microanalysis is important for photovoltaic functional thin films to characterize their homogeneity and purity. This demands combining spatial resolution in the micro/nano-scale and sensitivity in the trace-level range, which is at the moment beyond state-of-the-art. As dictated by counting statistics, the reduction of the spot size degrades the detection limit. The utilization of a tabletop XUV laser at λ = 46.9 nm has shown to dramatically improve the ablation efficiency with respect to that of visible lasers, such that ablation spot of 1 μm limits. Li-doped Cu2ZnSn(S,Se)4 (so-called kesterite) thin films were irradiated across 3D ablation arrays for hyperspectral mapping by means of time-of-flight mass spectrometry. The nominal 3D data node lattices were the initialisation perceptron, filled with measured values, and for a detailed supervised learning postprocessing, the node-to-node links were analysed by means of a 2D-kernel covariance algorithm. The latter permitted to obtain robust 3D elemental distribution functions well below the measurement spacing, giving insights into the inhomogeneity and impurities.
Characteristics of stratospheric polar vortex fluctuations associated with sea ice variability in the Arctic winter
Authors: Kim Jinju , Kim Kwang-Yul
Published: March 2020

The leading two modes of winter (November–February) Arctic sea ice cover variability and their linkage to stratospheric polar vortex variations are analyzed based on the cyclostationary EOF techniques. The first mode represents an accelerating trend of Arctic sea ice decline associated with Arctic amplification, particularly in the Barents and Kara Seas. The second mode is associated with decadal-scale phase shifts of dipole sea ice anomalies in the North Atlantic caused by NAO circulation. The first two modes of sea ice variability represent respectively a forced climate change and internal variability, and result in temporally and spatially distinct stratospheric polar vortex weakening. Sea ice reduction in the Barents and Kara Seas for the first mode is linked to a stratospheric vortex weakening during mid January–late February. The second mode with the dipole structure of positive sea ice anomalies in the Barents and Greenland Seas and negative anomalies in the Hudson Bay and Labrador Sea is related to a stratospheric vortex weakening during December–early February. The spatial evolutionary structure of anomalous polar vortex also exhibits differences between the two modes. When stratospheric anomalies are fully developed, stratospheric vortex is shifted to Eurasia in the first mode and to Europe in the second mode.
Dipping and rotating: two maneuvers to achieve maximum magnification during indirect transnasal laryngoscopy
Authors: Fleischer Susanne , Pflug Christina , Hess Markus
Published: March 2020

Background

Since many years, office-based flexible transnasal laryngoscopy is a common routine procedure. The development of new technical equipment such as high-definition cameras and flexible tip-chip endoscopes nowadays allows for much more precise examination than a few years ago. In contrast to rigid laryngoscopy, it is possible to move the tip of the endoscope close to the vocal folds and to other structures of interest. Nevertheless, without professional handling of the equipment, one cannot benefit from the potential of the newest technology.

Method

Two easily performed and very helpful maneuvers in flexible endoscopy are described. The “dipping maneuver” enables a maximum magnification of the mucosal surfaces of the endolarynx as well as the examination of the subglottal region and the trachea by positioning the tip of the endoscope very close to the vocal folds or even in the upper trachea during long transnasal inspiration. During the “rotation laryngoscopy”, the tip of the endoscope is positioned in the posterior interarytenoid region by rotating the flexible endoscope by 180° and advancing it close to the glottis. This allows a close-up examination of the anterior commissure, the inferior aspect of the vocal folds and the inside of the Morgagni’s ventricle. Before performing transnasal flexible endoscopy, we routinely apply topical anesthesia sprayed intranasally.

Conclusion

The described techniques of flexible endoscopy are easily performed and allow a maximum magnification of the mucosal surfaces and otherwise not visible regions of the endolarynx.
Post-extubation stridor after prolonged intubation in the pediatric intensive care unit (PICU): a prospective observational cohort study
Authors: Veder L. L. , Joosten K. F. M. , Schlink K. , Timmerman M. K. , Hoeve L. J. , van der Schroeff M. P. , Pullens B.
Published: March 2020

Purpose

Prolonged endotracheal intubation may lead to laryngeal damage, with stridor being the most relevant clinical symptom. Our objective was to determine the incidence of post-extubation stridor and their clinical consequences in children within a tertiary referral center and to identify contributing factors.

Methods

150 children, aged 0–16 years, intubated for more than 24 h were prospectively enrolled until discharge of the hospital. Potential relevant factors, thought to mediate the risk of laryngeal damage, were recorded and analyzed.

Results

The median duration of intubation was 4 days, ranging from 1 to 31 days. Stridor following extubation occurred in 28 patients (18.7%); 3 of them required reintubation due to respiratory distress and in 1 child stridor persisted for which a surgical intervention was necessary. In multivariate analyses, we found the following independent predictors of stridor: intubation on the scene, the use of cuffed tubes and lower age.

Conclusion

Despite a high incidence for post-extubation stridor, only few children need reintubation or surgical intervention as a result of post-extubation lesions. Intubation on the scene, the use of cuffed tubes and young age are associated with a significant increased risk of post-extubation stridor. Awareness of these factors gives the possibility to anticipate on the situation and to minimize laryngeal injury and its possible future consequences.
Neurological update: dizziness
Authors: Kaski Diego
Published: March 2020

The diagnosis and management of vertigo remains a challenge for clinicians, including general neurology. In recent years there have been advances in the understanding of established vestibular syndromes, and the development of treatments for existing vestibular diagnoses. In this ‘update’ I will review how our understanding of previously “unexplained” dizziness in the elderly is changing, explore novel insights into the pathophysiology of vestibular migraine, and its relationship to the newly coined term ‘persistent postural perceptual dizziness’, and finally discuss how a simple bedside oculomotor assessment may help identify vestibular presentations of stroke.
Impact of anti-epileptic drug choice on discharge in acute traumatic brain injury patients
Authors: Harris Lauren , Hateley Sofie , Tsang K. T. , Wilson M. , Seemungal B. M.
Published: March 2020

Background

Anti-epileptic drug (AED) prophylaxis in the first-seven days post-traumatic brain injury (TBI) is known to reduce seizure frequency acutely. AED efficacy is equivalent; therefore, choice of AED may rest with their side-effects. We hypothesise that AEDs that impair balance will prolong recovery, shown by a longer hospital stay. We compared length of hospital stay (and reported dizziness) in TBI patients receiving the commonest AEDs used in our TBI patients, Phenytoin (which may cause imbalance), and Levetiracetam (which does not affect balance).

Method

A retrospective observational study was performed on TBI patients admitted to a Major Trauma Unit between October 2013 and June 2018. 100 of 278 patients treated with phenytoin or levetiracetam monotherapy for seizure prophylaxis were included. The inclusion criteria of admission Glasgow Coma Score of 14 or more and length of stay less than 3 weeks minimised confounding variables such as non-ambulant patients. Length of hospital stay and incidence of dizziness were assessed.

Results

The length of hospital stay was longer for patients on Phenytoin versus Levetiracetam, i.e., 10.74 vs. 7.58 days (p = 0.015; unpaired, two-sided t test). Dizziness reported by patients on phenytoin was 24% and levetiracetam was 8% (p = 0.018; Chi-squared test).

Conclusion

In this cohort, using Phenytoin for acute TBI, seizure prophylaxis was associated with longer length of stay and more dizziness compared to Levetiracetam. Given their equivalent AED efficacy in acute TBI seizure prophylaxis, our data suggest that Levetiracetam is preferable to Phenytoin for early seizure prophylaxis in TBI. This requires evaluation in larger, prospective studies.
One more look on visualization of operation of a root-finding algorithm
Authors: Gościniak Ireneusz , Gdawiec Krzysztof
Published: March 2020

Many algorithms that iteratively find solution of an equation require tuning. Due to the complex dependence of many algorithm’s elements, it is difficult to know their impact on the work of the algorithm. The article presents a simple root-finding algorithm with self-adaptation that requires tuning, similarly to evolutionary algorithms. Moreover, the use of various iteration processes instead of the standard Picard iteration is presented. In the algorithm’s analysis, visualizations of the dynamics were used. The conducted experiments and the discussion regarding their results allow to understand the influence of tuning on the proposed algorithm. The understanding of the tuning mechanisms can be helpful in using other evolutionary algorithms. Moreover, the presented visualizations show intriguing patterns of potential artistic applications.
Indecomposable sets of finite perimeter in doubling metric measure spaces
Authors: Bonicatto Paolo , Pasqualetto Enrico , Rajala Tapio
Published: March 2020

We study a measure-theoretic notion of connectedness for sets of finite perimeter in the setting of doubling metric measure spaces supporting a weak$$(1,1)$$(1,1)-Poincaré inequality. The two main results we obtain are a decomposition theorem into indecomposable sets and a characterisation of extreme points in the space of BV functions. In both cases, the proof we propose requires an additional assumption on the space, which is called isotropicity and concerns the Hausdorff-type representation of the perimeter measure.