bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructure of injection moulding machine mould clamping mechanism: design and motion simulation
Authors: Jin Zhiming , Zhang Yajun , Wang Xinliang , Williams Jacob , Liu Zhen , Huang Zhongyuan , Falkner D'Lauren , Zhou Gang , Dong Liqun , Zhuang Jian , Wang Zhe
Published: March 2019

With the advent of intelligence technologies, more and more machines and devices are involved in the creation of complex structures. In the intelligent manufacturing industries, mouldings including injection moulding, blow moulding, compression moulding, and others play critical roles in manufacturing highly precise parts required for building intelligent machines (such as computers, cell phones, robots etc.). The performance of the clamping mechanism directly affects the quality of the microstructure of injection products. The design of the injection moulding mould clamping mechanism is based on the microstructure characteristics of the trip of the toggle lever mechanism ratio, speed ratio, and force amplification ratio. These are used to study the main performance parameters, such as analysis, as well as for the establishment of the physical model of the clamping mechanism. The model is based on the microstructure of injection of hyperbolic elbow clamping mechanism kinematics simulation. Simulation results and theoretical calculation contrast analysis show that the maximum dynamic template speed is 215.34 mm/s. The dynamic templates and cross‐head speed ratio is 2.15; therefore, the design of the injection moulding mould clamping mechanism for the microstructure provides favourable technical support. The method described here is important to build complicated moulds required to build highly precise parts to build intelligent machineries.
Fuzzification of attribute information granules and its formal reasoning model
Authors: Zhou Ruqi , Feng Jiali , Chang Huiyou , Zhou Yuepeng
Published: March 2019

The model of attribute information granule based on the method of attribute theory and the problem of fuzzification of attribute information granules are discussed. The concept of information granule given by Zadeh can be explained with an attribute and its qualitative mapping operator. Finally, this study also discusses the reasoning of granulation form of attribute fuzzification information which is based on the fuzzy Petri net, with the good formalisation structure of fuzzy Petri net, as well as its asynchronous, concurrency, uncertainty, and other characteristics which is similar to those of human cognitive activities, enabling the fuzzy Petri net to express the basic characteristics of a cognitive system in the form of computing attribute granules. The results of this study can provide a reference for the establishment of the granular logic model in the uncertain problems and a new interpretation framework for revealing the inherent laws of knowledge uncertainty's change with knowledge granularity, and also provides another new possible approach to the establishment of the machine learning model of fuzzy Petri net.
Technology and application of intelligent driving based on visual perception
Authors: Zhang Xinyu , Gao Hongbo , Xie Guotao , Gao Buyun , Li Deyi
Published: March 2019

The camera is one of the important sensors to realise the intelligent driving environment. It can realise lane detection and tracking, obstacle detection, traffic sign detection, identification and discrimination and visual simultaneous localisation and mapping. The visual sensor model, quantity and installation location are different on different intelligent driving hardware experimental platform as well as the visual sensor information processing module, thus a number of intelligent driving system software modules and interfaces are different. In this study, the software architecture of the autonomous vehicle based on the driving brain is used to adapt to different types of visual sensors. The target segment is extracted by the image segmentation algorithm, and then the segmentation of the region of interest is carried out. According to the input feature calculation results, the obstacle search is done in the second segmentation region, the output of the accessible road area. As driving information is complete, the authors will increase or reduce one or more visual sensors, change the visual sensor model or installation location, which will no longer directly affect the intelligent driving decision, they make the multi‐vision sensors adapted to the requirements of different intelligent driving hardware test platforms.
Enriching basic features via multilayer bag‐of‐words binding for Chinese question classification
Authors: Yang Sichun , Gao Chao
Published: March 2019

Question classification helps to generate more accurate answers in question answering system. For an efficient question classifier, one of the most important tasks is to fully mine useful features. Aiming at solving the problem of lacking of rich syntax and semantic features in Chinese question classification, an operator called MBWB (multilayer bag‐of‐words binding) is proposed to extract potential features by binding part‐of‐speech, word sense, named entity and other basic features to bag‐of‐words, respectively. Through performing MBWB operator on two kinds of bag‐of‐words, i.e. A_BOW and T_BOW, the corresponding A_MBWB and T_MBWB features are generated automatically. The MBWB operator can explore potential information contained in basic features, and enrich syntactic and semantic representation of questions. Experimental results on the Chinese question set show that the classification accuracy gets significantly improved when combining two kinds of MBWB features with basic features.
Proposal of initiative service model for service robot
Authors: Hao Man , Cao Weihua , Wu Min , Liu Zhentao , She Jinhua , Chen Luefeng , Zhang Ri
Published: March 2019

Service robots are becoming a part of today's life. To realise friendly human–robot interaction, an initiative service model for service robot is proposed, which is composed of three layers, i.e. information acquisition layer, in which communication information and environmental information are collected by sensors; decision layer, in which personal intention and emotional states are obtained by multi‐modal emotion recognition and intention understanding, and users' demands are obtained by demand analysis model; initiative service execution layer, in which the task execution and emotion adaption of robot are carried out. Initiative service can sense motive of people, by which a humanised and real‐time service could be realised. Drinking service experiments are performed, including passive service and initiative service of robots. Experimental results show that the drinking time of passive service lags behind the initiative service 30 min on average, and the initiative service renders drinking service 2 times more than passive service on average, besides, the water quantity provided by initiative service is more reasonable, which demonstrates the feasibility of the proposal. In prospect, initiative service model could be applied to many occasions in people's daily life, e.g. family service, caring for the elderly, and medical rehabilitation.
Lane detection algorithm based on temporal–spatial information matching and fusion
Authors: Wang Jun , Kong Bin , Mei Tao , Wei Hu
Published: March 2019

Given the problems of less single‐image information and poor anti‐interference ability, a lane detection algorithm based on temporal‐spatial information matching and fusion by reverse perspective transformation is proposed in this study. Using this algorithm, the images captured by a camera are first segmented with the binary features extracted from the effective ranges. Next, the feature images are transformed into their reverse perspectives in the top‐view space and are combined with the inertial navigation system (INS) information of the unmanned vehicle. The continuous multi‐frame feature image data undergo temporal‐spatial information matching and fusion in the top‐view space, thereby obtaining the lane feature images with abundant data within a wider range. Cluster analysis is then conducted on the feature image information after matching to achieve single‐lane feature data clustering and to filter out interference. Using the least‐squares curve‐fitting algorithm, the lane feature data are fitted to a parametric curve after clustering. Finally, a model of the prediction is established between two adjacent frame images to achieve lane tracking prediction and to further improve the accuracy of the lane detection. Experimental results show that the superior advantages of the algorithm include strong anti‐interference, high detection efficiency, and excellent algorithm stability and timelines.
Mobile robot indoor dual Kalman filter localisation based on inertial measurement and stereo vision
Authors: Cheng Lei , Song Biao , Dai Yating , Wu Huaiyu , Chen Yang
Published: March 2019

This study presents a novel navigation method designed to support a real‐time, efficient, accurate indoor localisation for mobile robot system. It is applicable for inertial measurement units (IMU) consisting of gyroscopes, accelerometers, and magnetic besides stereo vision (SV). The current indoor mobile robot localisation technology adopts traditional active sensing devices such as laser, and ultrasonic method which belongs to the signal of localisation and navigation method which has low efficiency complex structure, and poor anti‐interference ability. Through dual Kalman filter (DKF) algorithm, the accumulated error of gyroscope can be reduced, while combining with SV, mobile robot binocular SV orientation of inertial location can be realised under the DKF mechanism, which is introduced. First, high precision posture information of mobile robot can be obtained using fusing Kalman filter algorithm of accelerometer, gyroscope and magnetometer data. Second, inertial measurement precision can be optimised using Kalman filtering algorithm combined with machine vision localisation algorithm. The results indicate that the method achieves the levels of accuracy location comparable with that of the IMU/SV fusion algorithm; <0.0066 static RMS error, <0.0056 dynamic RMS error. The mobile robot using DKF algorithm of inertial navigation and SV indoor localisation is feasible.
Comparative analysis of solar radio bursts before and during CME propagation
Authors: Dididze G. , Shergelashvili B. M. , Melnik V. N. , Dorovskyy V. V. , Brazhenko A. I. , Poedts S. , Zaqarashvili T. V. , Khodachenko M.
Published: March 2019

Context. As is well known, coronal mass ejection (CME) propagation often results in the fragmentation of the solar atmosphere on smaller regions of density (magnetic field) enhancement (depletion). It is expected that this type of fragmentation may have radio signatures.

Aims. The general aim of the present paper is to perform a comparative analysis of type III solar and narrow-band type-III-like radio burst properties before and during CME events, respectively. The main goal is to analyze radio observational signatures of the dynamical processes in solar corona. In particular, we aim to perform a comparison of local plasma parameters without and with CME propagation, based on the analysis of decameter radio emission data.

Methods. In order to examine this intuitive expectation, we performed a comparison of usual type III bursts before the CME with narrow-band type-III-like bursts, which are observationally detectable on top of the background type IV radio bursts associated with CME propagation. We focused on the analysis of in total 429 type III and 129 narrow-band type-III-like bursts. We studied their main characteristic parameters such as frequency drift rate, duration, and instantaneous frequency bandwidth using standard statistical methods. Furthermore, we inferred local plasma parameters (e.g., density scale height, emission source radial sizes) using known definitions of frequency drift, duration, and instantaneous frequency bandwidth.

Results. The analysis reveals that the physical parameters of coronal plasma before CMEs considerably differ from those during the propagation of CMEs (the observational periods 2 and 4 with type IV radio bursts associated with CMEs). Local density radial profiles and the characteristic spatial scales of radio emission sources vary with radial distance more drastically during the CME propagation compared to the cases of quasistatic solar atmosphere without CME(s) (observational periods 1 and 3).

Conclusions. The results of the work enable us to distinguish different regimes of plasma state in the solar corona. Our results create a solid perspective from which to develop novel tools for coronal plasma studies using radio dynamic spectra.
Physical Bayesian modelling of the non-linear matter distribution: New insights into the nearby universe
Authors: Jasche J. , Lavaux G.
Published: March 2019

Accurate analyses of present and next-generation cosmological galaxy surveys require new ways to handle effects of non-linear gravitational structure formation processes in data. To address these needs we present an extension of our previously developed algorithm for Bayesian Origin Reconstruction from Galaxies (BORG) to analyse matter clustering at non-linear scales in observations. This is achieved by incorporating a numerical particle mesh model of gravitational structure formation into our Bayesian inference framework. The algorithm simultaneously infers the three-dimensional primordial matter fluctuations from which present non-linear observations formed and provides reconstructions of velocity fields and structure formation histories. The physical forward modelling approach automatically accounts for the non-Gaussian features in gravitationally evolved matter density fields and addresses the redshift space distortion problem associated with peculiar motions of observed galaxies. Our algorithm employs a hierarchical Bayes approach to jointly account for various observational effects, such as unknown galaxy biases, selection effects, and observational noise. Corresponding parameters of the data model are marginalized out via a sophisticated Markov chain Monte Carlo approach relying on a combination of a multiple block sampling framework and an efficient implementation of a Hamiltonian Monte Carlo sampler. We demonstrate the performance of the method by applying it to the 2M++ galaxy compilation, tracing the matter distribution of the nearby universe. We show accurate and detailed inferences of the three-dimensional non-linear dark matter distribution of the nearby universe. As exemplified in the case of the Coma cluster, our method provides complementary mass estimates that are compatible with those obtained from weak lensing and X-ray observations. For the first time, we also present a reconstruction of the vorticity of the non-linear velocity field from observations. In summary, our method provides plausible and very detailed inferences of the dark matter and velocity fields of our cosmic neighbourhood.
A novel fourth-order WENO interpolation technique
Authors: Janett Gioele , Steiner Oskar , Alsina Ballester Ernest , Belluzzi Luca , Mishra Siddhartha
Published: March 2019

Context. Several numerical problems require the interpolation of discrete data that present at the same time (i) complex smooth structures and (ii) various types of discontinuities. The radiative transfer in solar and stellar atmospheres is a typical example of such a problem. This calls for high-order well-behaved techniques that are able to interpolate both smooth and discontinuous data.

Aims. This article expands on different nonlinear interpolation techniques capable of guaranteeing high-order accuracy and handling discontinuities in an accurate and non-oscillatory fashion. The final aim is to propose new techniques which could be suitable for applications in the context of numerical radiative transfer.

Methods. We have proposed and tested two different techniques. Essentially non-oscillatory (ENO) techniques generate several candidate interpolations based on different substencils. The smoothest candidate interpolation is determined from a measure for the local smoothness, thereby enabling the essentially non-oscillatory property. Weighted ENO (WENO) techniques use a convex combination of all candidate substencils to obtain high-order accuracy in smooth regions while keeping the essentially non-oscillatory property. In particular, we have outlined and tested a novel well-performing fourth-order WENO interpolation technique for both uniform and nonuniform grids.

Results. Numerical tests prove that the fourth-order WENO interpolation guarantees fourth-order accuracy in smooth regions of the interpolated functions. In the presence of discontinuities, the fourth-order WENO interpolation enables the non-oscillatory property, avoiding oscillations. Unlike Bézier and monotonic high-order Hermite interpolations, it does not degenerate to a linear interpolation near smooth extrema of the interpolated function.

Conclusion. The novel fourth-order WENO interpolation guarantees high accuracy in smooth regions, while effectively handling discontinuities. This interpolation technique might be particularly suitable for several problems, including a number of radiative transfer applications such as multidimensional problems, multigrid methods, and formal solutions.
H/C elemental ratio of the refractory organic matter in cometary particles of 67P/Churyumov-Gerasimenko
Authors: Isnard R. , Bardyn A. , Fray N. , Briois C. , Cottin H. , Paquette J. , Stenzel O. , Alexander C. , Baklouti D. , Engrand C. , Orthous-Daunay F.-R. , Siljeström S. , Varmuza K. , Hilchenbach M.
Published: March 2019

Context. Because comets are part of the most primitive bodies of our solar system, establishing their chemical composition and comparing them to other astrophysical bodies gives new constraints on the formation and evolution of organic matter throughout the solar system. For two years, the time-of-flight secondary ion mass spectrometer COmetary Secondary Ion Mass Analyzer (COSIMA) on board the Rosetta orbiter performed in situ analyses of the dust particles ejected from comet 67P/Churyumov-Gerasimenko (67P).

Aims. The aim is to determine the H/C elemental ratio of the refractory organic component contained in cometary particles of 67P.

Methods. We analyzed terrestrial and extraterrestrial calibration samples using the COSIMA ground-reference model. Exploiting these calibration samples, we provide calibration lines in both positive and negative ion registration modes. Thus, we are now able to measure the cometary H/C elemental ratio.

Results. The mean H/C value is 1.04 ± 0.16 based on 33 different cometary particles. Consequently, the H/C atomic ratio is on average higher in cometary particles of 67P than in even the most primitive insoluble organic matter extracted from meteorites.

Conclusions. These results imply that the refractory organic matter detected in dust particles of 67P is less unsaturated than the material in meteorites.
Six new supermassive black hole mass determinations from adaptive-optics assisted SINFONI observations
Authors: Thater Sabine , Krajnović Davor , Cappellari Michele , Davis Timothy A. , de Zeeuw P. Tim , McDermid Richard M. , Sarzi Marc
Published: March 2019

Different massive black hole mass – host galaxy scaling relations suggest that the growth of massive black holes is entangled with the evolution of their host galaxies. The number of measured black hole masses is still limited and additional measurements are necessary to understand the underlying physics of this apparent coevolution. We add six new black hole mass (MBH) measurements of nearby fast rotating early-type galaxies to the known black hole mass sample, namely NGC 584, NGC 2784, NGC 3640, NGC 4570, NGC 4281, and NGC 7049. Our target galaxies have effective velocity dispersions (σe) between 170 and 245 km s−1, and thus this work provides additional insight into the black hole properties of intermediate-mass early-type galaxies. We combined high-resolution adaptive-optics SINFONI data with large-scale MUSE, VIMOS and SAURON data from ATLAS3D to derive two-dimensional stellar kinematics maps. We then built both Jeans Anisotropic Models and axisymmetric Schwarzschild models to measure the central black hole masses. Our Schwarzschild models provide black hole masses of (1.3 ± 0.5) × 108 M⊙ for NGC 584, (1.0 ± 0.6) × 108 M⊙ for NGC 2784, (7.7 ± 5) × 107 M⊙ for NGC 3640, (5.4 ± 0.8) × 108 M⊙ for NGC 4281, (6.8 ± 2.0) × 107 M⊙ for NGC 4570, and (3.2 ± 0.8) × 108 M⊙ for NGC 7049 at 3σ confidence level, which are consistent with recent MBH−σe scaling relations. NGC 3640 has a velocity dispersion dip and NGC 7049 a constant velocity dispersion in the center, but we can clearly constrain their lower black hole mass limit. We conclude our analysis with a test on NGC 4570 taking into account a variable mass-to-light ratio (M/L) when constructing dynamical models. When considering M/L variations linked mostly to radial changes in the stellar metallicity, we find that the dynamically determined black hole mass from NGC 4570 decreases by 30%. Further investigations are needed in the future to account for the impact of radial M/L gradients on dynamical modeling.
Long uninterrupted photometric observations of the Wolf-Rayet star EZ CMa by the Toronto BRITE satellite reveal a very fast apsidal motion
Authors: Schmutz W. , Koenigsberger G.
Published: March 2019

Context. The variability of the Wolf-Rayet star EZ CMa has been documented for close to half a century, and a clear periodicity of ∼3.7 days is established. However, all attempts to prove that it is a binary have failed because the photometric, spectroscopic, and polarimetric variations are not coherent over more than a few orbital cycles.

Aims. In this Letter we show that the lack of coherence in the variability can be explained with a very rapid apsidal motion in a binary orbit.

Methods. We measured the times of minima in a recently published exceptionally long photometric light curve obtained by the Toronto BRITE satellite. The apsidal motion and the system eccentricity are determined from the length of the time intervals between these minima, which alternate in their duration, following a pattern that is clearly associated with apsidal motion. These minima are superposed on brightness enhancements of the emission from a shock zone, which occur at about the times of periastron phases.

Results. We determine the orbital periodicity, Pa = 3.63 d, and the period of the apsidal motion, U ≃ 100 d, which together yield an average sidereal period of Ps = 3.77 d. The eccentricity is found to be close to 0.1. The rate of periapsis retreat changes significantly over the period of observation and is determined to be −16° P−1a at the beginning of the observing period and −10° P−1a at the end.

Conclusions. We demonstrate that by introducing a fast apsidal motion, the basic photometric variability is very well explained. The binary nature of EZ CMa is now established. This might imply that other apparently single Wolf-Rayet stars that emit hard X-rays, similar to EZ CMa, are also binaries.
Old and young stellar populations in DustPedia galaxies and their role in dust heating
Authors: Nersesian A. , Xilouris E. M. , Bianchi S. , Galliano F. , Jones A. P. , Baes M. , Casasola V. , Cassarà L. P. , Clark C. J. R. , Davies J. I. , Decleir M. , Dobbels W. , De Looze I. , De Vis P. , Fritz J. , Galametz M. , Madden S. C. , Mosenkov A. V. , Trčka A. , Verstocken S. , Viaene S. , Lianou S.
Published: March 2019

Aims. Within the framework of the DustPedia project we investigate the properties of cosmic dust and its interaction with stellar radiation (originating from different stellar populations) for 814 galaxies in the nearby Universe, all observed by the Herschel Space Observatory.

Methods. We take advantage of the widely used fitting code CIGALE, properly adapted to include the state-of-the-art dust model THEMIS. For comparison purposes, an estimation of the dust properties is provided by approximating the emission at far-infrared and sub-millimeter wavelengths with a modified blackbody. Using the DustPedia photometry we determine the physical properties of the galaxies, such as the dust and stellar mass, the star-formation rate, the bolometric luminosity, the unattenuated and the absorbed by dust stellar light, for both the old (> 200 Myr) and young (≤200 Myr) stellar populations.

Results. We show how the mass of stars, dust, and atomic gas, as well as the star-formation rate and the dust temperature vary between galaxies of different morphologies and provide recipes to estimate these parameters given their Hubble stage (T). We find a mild correlation between the mass fraction of the small a-C(:H) grains with the specific star-formation rate. On average, young stars are very efficient in heating the dust, with absorption fractions reaching as high as ∼77% of the total unattenuated luminosity of this population. On the other hand, the maximum absorption fraction of old stars is ∼24%. Dust heating in early-type galaxies is mainly due to old stars, up to a level of ∼90%. Young stars progressively contribute more for “typical” spiral galaxies and they become the dominant source of dust heating for Sm-type and irregular galaxies, with ∼60% of their luminosity contributing to that purpose. Finally, we find a strong correlation of the dust heating fraction by young stars with morphology and the specific star-formation rate.
Rendements et pratiques des cultures maraîchères en agriculture biologique au Sénégal
Authors: de Bon Hubert , Brun-Diallo Laure , Sène Jean-Michel , Simon Serge , Sow Mamadou Abdoulaye
Published: March 2019

Les rendements en agriculture biologique font l’objet de controverses et sont considérés comme plus faibles qu’en agriculture conventionnelle. En Afrique, l’agriculture biologique recouvre une grande diversité de pratiques et les rendements présentent de fortes incertitudes. Les analyses des rendements et des itinéraires techniques en agriculture biologique sont présentées pour trois cultures maraîchères au Sénégal. Les résultats sont ensuite comparés aux rendements usuels de l’agriculture conventionnelle. Deux types de données sont utilisés, provenant de parcelles d’agriculteurs : i) suivi de champs conduits selon des itinéraires techniques d’agriculture biologique vs. itinéraires techniques conventionnels ; ii) résultats issus des actions de l’organisation non gouvernementale ENDA-PRONAT, suivant un cahier des charges copié sur celui de l’agriculture biologique. Les suivis comparatifs de parcelles de chou pommé et de tomate en saison des pluies mettent en évidence des ratios de rendement agriculture biologique/conventionnelle de 74 et 40 % respectivement. Ces valeurs confirment la tendance générale des résultats de la littérature. Elles sont expliquées par une fertilisation azotée plus faible et l’absence de mesures de protection efficace contre les maladies et ravageurs des cultures. Les rendements en oignon des parcelles d’agriculture biologique chez les producteurs sont très variables : en moyenne de 19,4 t/ha à 11,0 t/ha suivant les années dans la zone des Niayes, 21,0 t/ha dans le Bassin arachidier et seulement 8,6 t/ha dans la vallée du fleuve Sénégal. Les rendements de la culture d’oignon au Sénégal observés dans la littérature varient aussi dans de grandes proportions, de 10,7 à 32 t/ha. Dans certains cas, les rendements en agriculture biologique sont supérieurs à ceux des itinéraires techniques de l’agriculture conventionnelle. Ce constat, déjà observé dans la littérature scientifique, montre que l’agriculture biologique est une voie de développement de l’agriculture à ne pas écarter en Afrique.
Powder-bed additive manufacturing for aerospace application: Techniques, metallic and metal/ceramic composite materials and trends
Authors: Katz-Demyanetz Alexander , Popov Vladimir V. , Kovalevsky Aleksey , Safranchik Daniel , Koptyug Andrey
Published: March 2019

The current paper is devoted to classification of powder-bed additive manufacturing (PB-AM) techniques and description of specific features, advantages and limitation of different PB-AM techniques in aerospace applications. The common principle of “powder-bed” means that the used feedstock material is a powder, which forms “bed-like” platform of homogeneous layer that is fused according to cross-section of the manufactured object. After that, a new powder layer is distributed with the same thickness and the “printing” process continues. This approach is used in selective laser sintering/melting process, electron beam melting, and binder jetting printing. Additionally, relevant issues related to powder raw materials (metals, ceramics, multi-material composites, etc.) and their impact on the properties of as-manufactured components are discussed. Special attention is paid to discussion on additive manufacturing (AM) of aerospace critical parts made of Titanium alloys, Nickel-based superalloys, metal matrix composites (MMCs), ceramic matrix composites (CMCs) and high entropy alloys. Additional discussion is related to the quality control of the PB-AM materials, and to the prospects of new approaches in material development for PB-AM aiming at aerospace applications.
Coenzyme Q2is a universal substrate for the measurement of respiratory chain enzyme activities in trypanosomatids
Authors: Čermáková Petra , Kovalinka Tomáš , Ferenczyová Kristína , Horváth Anton
Published: March 2019

The measurement of respiratory chain enzyme activities is an integral part of basic research as well as for specialized examinations in clinical biochemistry. Most of the enzymes use ubiquinone as one of their substrates. For currentin vitromeasurements, several hydrophilic analogues of native ubiquinone are used depending on the enzyme and the workplace. We tested five readily available commercial analogues and we showed that Coenzyme Q2is the most suitable for the measurement of all tested enzyme activities. Use of a single substrate in all laboratories for several respiratory chain enzymes will improve our ability to compare data, in addition to simplifying the stock of chemicals required for this type of research.
Penismetastase eines Speicheldrüsenkarzinoms der Zungenbasis: Ein Fallbeispiel
Authors: Tischler Tamara , Trenti Emanuela , Basciu Maria , Hanspeter Esther , Pycha Armin , Kafka Mona , Comploj Evi
Published: March 2019

Wir berichten über einen 64-jährigen Patienten mit einer Penismetastase zehn Jahre nach Erstdiagnose eines polymorphen Adenokarzinoms der kleinen Speicheldrüsen der Zungenbasis. Unserer Kenntnis gibt es bis dato nur zwei in der Literatur beschriebene Fälle.
Trends in der Prävalenz von Demenz und Parkinson – Eine Analyse auf Basis aller gesetzlich versicherten Personen im Alter 65+in Deutschland zwischen 2009 und 2012
Authors: Nerius Michael , Ziegler Uta , Doblhammer Gabriele , Fink Anne
Published: March 2019

Ziel Durch die Bevölkerungsalterung wird es einen Anstieg von Personen mit Demenz (DEM) und der Parkinson-Krankheit (PD) geben. Für eine verlässliche Public-Health-Planung ist es Ziel dieser Studie, Prävalenzen und Trends von Prävalenzen von DEM und PD für Deutschland zu ermitteln.

Methodik Für die Jahre 2009 bis 2012 wurden auf Basis einer Vollerhebung der Daten der gesetzlichen Krankenversicherungen (GKVs) geschlechtsspezifische Periodenprävalenzen für fünfjährige Altersgruppen von DEM und PD berechnet. Zeittrends wurden mittels einer negativen Binomialregression geschätzt.

Ergebnisse Im Jahr 2012 und Alter 65+lag die rohe Prävalenz für DEM bei 7,9% und für PD bei 2,2%. Zwischen 2009 und 2012 war ein durchschnittlicher Rückgang der DEM-Prävalenz für über 65-jährige Frauen und Männer um 1,2% pro Jahr zu verzeichnen. Für PD finden wir gleichbleibende Raten zwischen 2009 und 2012 für Männer und einen Rückgang von 0,5% pro Jahr bei den Frauen.

Schlussfolgerung Eine Reduzierung der DEM-Prävalenz von 1,2% pro Jahr kann dem Anstieg der Personen mit DEM aufgrund der Bevölkerungsalterung in den kommenden Jahren zumindest teilweise entgegenwirken. Bei PD hingegen zeichnet sich derzeit nur bei den Frauen eine Reduktion der Prävalenz ab.
On-site comparison of an enzymatic detergent and a non-enzymatic detergent-disinfectant for routine manual cleaning of flexible endoscopes
Authors: Gonzalez Jonathan , Vanzieleghem Thomas , Dumazy Axelle , Meuris Christelle , Mutsers Jacques , Christiaens Genevieve , Leclercq Philippe , Loly Jean-Philippe , Louis Edouard , Gast Pierrette
Published: March 2019

Background and study aims Flexible endoscopes are potential vectors of pathogen transmission to patients that are subjected to cleaning and high-level disinfection after each procedure. Efficient manual cleaning is a prerequisite for effective high-level disinfection. The goal of this study was to demonstrate the impact of the cleaning chemistry in the outcome of the manual cleaning of endoscopes.

Materials and methods Twelve endoscopes were included in this study: four colonoscopes, four gastroscopes, two duodenoscopes and two bronchoscopes. This study was designed with two phases; in each of them, the manual cleaning procedure remained identical, but a different detergent was used: a non-enzymatic detergent-disinfectant (NEDD) and an enzymatic detergent (ED). Biopsy and suction channels of endoscopes were sampled using 10 mL of physiological saline at two points: before and after manual cleaning, and adenosine triphosphate (ATP) was measured on each sample. In total, 208 procedures were analyzed for the NEDD phase and 253 for the ED phase.

Results For each endoscope type, cleaning endoscopes with ED resulted in larger median decrease in ATP than with NEDD: respectively 99.43 % and 95.95 % for bronchoscopes (P = 0.0007), 99.28 % and 96.93 % for colonoscopes (P < 0.0001) and 98.36 % and 95.36 % for gastroscopes (P < 0.0001). In addition, acceptability rates of endoscopes based on defined post-manual cleaning ATP thresholds (200, 150, 100 or 50 relative light units) for all endoscope types were significantly higher with ED compared to NEDD.

Conclusions With all other parameters of manual cleaning remaining unchanged, the enzymatic chemistry of ED provided more consistent and improved cleaning of endoscopes compared to NEDD. Therefore, choice of the detergent for endoscope cleaning has an impact on the outcome of this process.
Preoperative endoscopic predictors of severe submucosal fibrosis in colorectal tumors undergoing endoscopic submucosal dissection
Authors: Kaosombatwattana Uayporn , Yamamura Takeshi , Limsrivilai Julajak , Nakamura Masanao , Leelakusolvong Somchai , Hirooka Yoshiki , Goto Hidemi
Published: March 2019

Background and study aims Endoscopic submucosal dissection (ESD) enables en bloc removal of colorectal neoplasms regardless of size. Submucosal fibrosis is a significant factor for technical difficulty and poor outcomes. We assessed the predictive factors for severe submucosal fibrosis and the ESD outcomes.

Patients and methods Patients undergoing ESD from January 2006 to September 2017 were retrospectively reviewed. The degree of submucosal fibrosis was classified into three types: no fibrosis (F0), mild fibrosis (F1), and severe fibrosis (F2). F0 and F1 cases were grouped as non-severe fibrosis for comparison with the severe fibrosis group. Predictors of severe submucosal fibrosis and ESD outcomes were evaluated.

Results ESD was performed in 524 lesions (60 % male; mean age, 67.8 years). Eighty lesions with severe fibrosis (15.3 %) were observed. The overall en bloc resection rate and curative resection rate were 94.3 % and 77.7 %, respectively. Rates of en bloc resection (91.2 % vs. 94.8 %, P = 0.2) and perforation (7.5 % vs. 5.6 %, P = 0.45) were no different between severe fibrosis and non-severe fibrosis groups. However, incidences of non-curative resection and low resection speed were significantly higher in the severe fibrosis group. Among protruding lesions, tumor height and volume were significantly greater in the severe counterparts. A diameter ≥ 40 mm, endoscopic finding of the tumor beyond fold, and fold convergence were independent risk factors for severe fibrosis.

Conclusions Severe submucosal fibrosis is a significant risk factor for non-curative resection and a long procedural time. Tumor size and morphology might help to predict the severity of fibrosis.
Arztgesundheit: Was macht uns krank – Was hält uns gesund?
Authors: Braun Jörg , Jocham Dieter
Published: March 2019

Der Arztberuf ist besonders gesundheitsgefährdend. Innere Gründe hierfür sind verbreitete Selbstdiagnostik und Selbsttherapie, der Präsentismus (Arbeiten trotz Krankheit), erhöhte Risiken für Suchterkrankungen und Suizid. Äußere Gründe sind Infektionskrankheiten, Gewalt gegen Heilberufler, die u. a. aufgrund der Ökonomisierung zunehmend schwierigen Arbeitsbedingungen und das Posttraumatische Belastungssyndrom. Es wird daher zunehmend nötig, sich proaktiv um die eigene Gesundheit zu kümmern. Die wissenschaftliche Auseinandersetzung mit der Problematik Arztgesundheit belegt als typische zugrunde liegende Mechanismen den häufig hohen Selbstanspruch und die mangelnde Selbstfürsorge von Ärzten und Ärztinnen. U.a. diese Ansatzpunkte und verfügbare Programme (kognitiv-emotionale Reflektion, Stressmanagement, Entspannungs-Praktiken, Konfliktlösung, Achtsamkeit, Priming, Framing, Meditation, Embodiment u. a.) zur Stärkung der Resilienz Betroffener eröffnen Möglichkeiten für die Optimierung der Salutogenese der im Gesundheitswesen Beschäftigten. Der Übersichtsartikel stellt die Zusammenhänge und Konzepte für die Stärkung der Resilienz bei Heilberuflern dar.
Association between endoscopic findings of eosinophilic esophagitis and responsiveness to proton pump inhibitors
Authors: Sawada Akinari , Hashimoto Atsushi , Uemura Risa , Otani Koji , Tanaka Fumio , Nagami Yasuaki , Yamagami Hirokazu , Tanigawa Tetsuya , Watanabe Toshio , Fujiwara Yasuhiro
Published: March 2019

Background and study aims Endoscopic findings of esophageal eosinophilia sometimes localize to small areas of the esophagus. A previous study suggested that pathogenesis of localized-type eosinophilic esophagitis (LEoE) was associated with acid reflux. However, LEoE treatment outcomes have not been studied. We aimed to analyze the clinical and histologic significance of LEoE in comparison with diffuse-type eosinophilic esophagitis (DEoE).

Patients and methods This study included 106 patients with esophageal eosinophilia. Esophageal eosinophilia was defined as a condition where the maximum number of intraepithelial eosinophils was ≥ 15 per high-power field. LEoE was defined as an endoscopic lesion confined to one-third of the esophagus: upper, middle, or lower. Esophageal eosinophilia encompassing more than two-thirds of the esophagus was defined as DEoE. We retrospectively compared LEoE and DEoE in terms of clinical characteristics, histologic findings, and proportion of proton pump inhibitor (PPI) responders.

Results Of 106 patients, 12 were classified as having LEoE and 94 were classified as having DEoE. The proportion of asymptomatic patients was significantly higher in the LEoE group than the DEoE group (42 % vs 7 %, P < 0.01). In the LEoE group, 10 patients (84 %) had endoscopic lesions in the lower esophagus. The maximum number of eosinophils did not differ between the groups (54 [24 – 71] for LEoE, 40 [20 – 75] for DEoE, P = 0.65). The prevalence of PPI responders was significantly higher in the LEoE group than the DEoE group (100 % vs 63 %, P = 0.01).

Conclusion LEoE can be a sign of good responsiveness to PPI therapy.
Hemodynamic Comparison of Sutureless and Rapid-Deployment Valves with Conventional Bioprostheses
Authors: Gotzmann Max , Wilbring Manuel , Charitos Efstratios , Treede Hendrik , Silaschi Miriam
Published: March 2019

Background Sutureless and rapid-deployment bioprostheses (RPDs) are advantageous due to shorter aortic cross-clamp times (ACCs); however, few studies have investigated hemodynamic outcomes in comparison to conventional bioprostheses (CBs).

Methods All patients receiving the Perceval (LivaNova, London, United Kingdom) and Intuity (Edwards Lifesciences, Irvine, California, United States) valves from February 2016 to December 2017 were included (n = 61). For controls, patients who underwent aortic valve replacement using CB from 2015 to 2018 (n = 743) were propensity-matched (n = 108). Primary end points were mean gradient at discharge, true internal diameter (ID) after implantation, and paravalvular leakage. Secondary end points were ACCs, cardiopulmonary bypass times (CPBTs), mortality, and pacemaker implantation.

Results Age was 73.2 years (standard deviation [SD]: 7.6) in the RPD group and 72.9 years (SD: 7.3) in the CB group (p = 0.827). Median logistic EuroSCORE II was 3.4% (Q1: 2; IQ3: 5.3) and 3% (Q1: 1.9; IQ3: 5.6; p = 0.599). While ACCs and CPBT were shorter in RPDs (97 [SD: 31.4] vs. 125.4 minutes [SD: 62.1], p = 0.003; and 76.1 [SD: 25.7] vs. 89.7 minutes [SD: 34.3], p = 0.022), procedural times were similar (p = 0.257). True ID was 21.97 mm (SD: 1.79) in RPDs and 20.15 mm (SD: 1.70) in CB (p < 0.001).

RPDs and CB resulted in comparable mean gradients (12.8 mm Hg [SD: 6.4] vs. 13.8 mm Hg [SD: 5.6]; p = 0.387) and rate of paravalvular regurgitation. There were no differences in the rates of pacemaker implantation and mortality.

In a subanalysis of RPDs, mean gradient was 15.48 mm Hg (SD: 7.51) in Perceval (n = 21) and 10.79 mm Hg (SD: 4.78) in Intuity (n = 33; p = 0.010).

Conclusions RPDs provided comparable hemodynamic performance, although implanted valves were larger in true ID. Whether this provides superior hemodynamic performance during exercise and longer durability needs further investigation. Among RPDs, the Intuity valve provided lower mean gradients at rest than Perceval valve.
Incident Co-Morbidities in Patients with Atrial Fibrillation Initially with a CHA2DS2-VASc Score of 0 (Males) or 1 (Females): Implications for Reassessment of Stroke Risk in Initially ‘Low-Risk’ Patients
Authors: Chao Tze-Fan , Liao Jo-Nan , Tuan Ta-Chuan , Lin Yenn-Jiang , Chang Shih-Lin , Lo Li-Wei , Hu Yu-Feng , Chung Fa-Po , Chen Tzeng-Ji , Lip Gregory Y. H. , Chen Shih-Ann
Published: March 2019

Background Oral anticoagulants (OACs) are not recommended for ‘low-risk’ patients with atrial fibrillation (AF). We investigated the incidences of new risk factors developing, and the temporal trends in the CHA2DS2-VASc score in initially ‘low-risk’ AF patients. Second, we propose a reasonable timing interval at which stroke risk should be reassessed for such AF patients.

Methods We studied 14,606 AF patients who did not receive anti-platelet agents or OACs with a baseline CHA2DS2-VASc score of 0 (males) or 1 (females). The CHA2DS2-VASc scores of patients were followed up and updated until the occurrence of ischaemic stroke or mortality or 31 December 2011. The associations between the prescription of warfarin and risk of adverse events once patients' scores changed were analysed. Decile values of durations to incident co-morbidities and from the acquirement of new co-morbidities to ischaemic stroke were studied.

Results During a mean follow-up of 4 years, 7,079 (48.5%) patients acquired at least one new stroke risk factor component(s) with annual risks of 6.35% for hypertension, 3.68% for age ≥ 65 years, 2.77% for heart failure, 1.99% for diabetes mellitus and 0.33% for vascular diseases. The incidence for CHA2DS2-VASc score increments was 12.1%/year. Initiation of warfarin was associated with a lower risk of adverse events (adjusted hazard ratio, 0.530; 95% confidence interval, 0.371–0.755). Among 6,188 patients who acquired new risk factors, 80% would acquire these co-morbidities after 4.2 months of AF diagnosis. The duration from the acquirement of incident co-morbidities to the occurrence of ischaemic stroke was longer than 4.4 months for 90% of the patients.

Conclusion The CHA2DS2-VASc score increases in approximately 12% of initially ‘low-risk’ AF patients each year, and the initiation of warfarin once the score changed was associated with a better prognosis. Three to four months may be a reasonable timing interval at which stroke risk should be reassessed so that OACs could be prescribed in a timely manner for stroke prevention.
Improving agricultural microinsurance by applying universal kriging and generalised additive models for interpolation of mean daily temperature
Authors: Roznik Mitchell , Brock Porth C. , Porth Lysa , Boyd Milton , Roznik Katerina
Published: March 2019

Agricultural microinsurance has the potential to protect farmers against crop loss caused by extreme adverse weather conditions. Microinsurance policies for smallholder farmers are often designed on the basis of weather indices, whereby weather insurance variables are measured at ground weather stations and then interpolated to the location of the farm. However, a low density of weather stations causes interpolation error, which contributes to basis risk. The objective of this paper is to investigate whether agricultural microinsurance can be improved by reducing interpolation error through advanced interpolation methods, including universal kriging (UK) and generalised additive models (GAM) used with land surface temperature, elevation, and other covariates. Results indicate that for areas with a lower density of weather stations, UK with elevation substantially improves air temperature interpolation accuracy. The approach developed in this paper may help to improve interpolation and could therefore reduce basis risk for agricultural microinsurance in regions with a low density of weather stations, such as in developing countries.
Temporal evolution of photoinduced optical chirality in nanostructured light-sensitive waveguide thin films: Simultaneous excitation of TE and TE1 modes
Authors: Nahal Arashmid , Asaakareh Bentolhoda , Miri MirFaez
Published: March 2019

Optical properties of the self-organized gratings in thin photosensitive waveguide AgCl films on a glass substrate, doped by Ag nanoparticles, in the case of simultaneous excitation of TE0 and TE1 modes are investigated. These gratings are a result of interference of the incident linear polarized He-Ne laser beam with the excited TEn-modes of the AgCl layer. The interference field patterns the re-distribution of the nanoparticles. Each excited mode generates its own grating. The self-organized gratings associated with the TE0 mode appear earlier than that of the TE1 mode. There is a competition between TE0-gratings and TE1-gratings for absorbing the nanoparticles, because their available amount is limited in the interaction area. The competition is due to the positive feedback of the light mechanism. Thus, the TE1-grating removes some Ag nanoparticles from the already generated TE0-grating, which forms some chiral complex building blocks of the gratings. The induced chirality leads to the induction and enhancement of optical activities in the samples. Longer exposure of the samples leads to the variation of induced optical chirality. Generation of the gratings increases anisotropy of the sample, which in turn enhances the chiroptical properties of the Ag/AgCl/Glass system. Changes in absorption spectra, induced dichroism, and induced optical gyrotropy of the samples are measured. Diffraction patterns of the exposed samples confirm the coexistence of TE0- and TE1-associated gratings and their competition. AFM images support the above-mentioned process. It is observed that longer exposure and perfect formation of the induced gratings accompany with the reduction of chiroptical property, due to the destruction of chiral complex silver nanoclusters.