bluuebunny/crossref_metadata_2025 huggingface dataset:
The PI3K/Akt and NF-κB signaling pathways are involved in the protective effects ofLithocarpus polystachyus(sweet tea) on APAP-induced oxidative stress injury in mice
Authors: Yang Jia-yu , Zhong Yu-te , Hao Wei-nan , Liu Xiang-xiang , Shen Qiong , Li Yan-fei , Ren Shen , Wang Zi , Li Wei , Zhao Li-Chun
Published: May 2020

Acetaminophen (APAP)-induced acute liver injury (ALI) is a health issue that has gradually attracted attention, and is often regarded as a model of drug-induced hepatotoxicity.
An ultra-sensitive T2-weighted MR contrast agent based on Gd3+ ion chelated Fe3O4 nanoparticles
Authors: Chen Jing , Xiang Hui-Hui , Zhao Zu-Zhi , Wu Yun-Kai , Fei Meng-Yu , Song Meng-Meng
Published: May 2020

An ultra-sensitive T2-weighted MR imaging contrast agent was prepared based on Fe3O4 nanoparticles and Gd3+ ions (Fe3O4@Gd).
Synergistic effect of the anti-solvent bath method and improved annealing conditions for high-quality triple cation perovskite thin films
Authors: Adams Geoffrey Ryan , Eze Vincent Obiozo , Carani Lucas Braga , Pino Aaron , Jolowsky Claire , Okoli Okenwa I.
Published: May 2020

High quality triple cation perovskite thin films realized through the combination of the anti-solvent bath method and low temperature annealing.
The effect of continuous tubular reactor technologies on the pretreatment of lignocellulosic biomass at pilot-scale for bioethanol production
Authors: Pérez-Pimienta José A. , Papa Gabriela , Gladden John M. , Simmons Blake A. , Sanchez Arturo
Published: May 2020

A pilot-scale continuous tubular reactor increases enzymatic digestibility of four different feedstocks by removing xylan and effectively achieving economically viable ethanol concentrations.
Potassium phosphate monobasic induced decoration from the surface into the bulk lattice for Ni-rich cathode materials with enhanced cell performance
Authors: Zhang Dianwei , Li Yunjiao , Xi Xiaoming , Chang Shenghong , Wang Shan , Yang Jiachao , Zheng Junchao , Li Wei
Published: May 2020

The interfacial instability and intrinsic structural degradation of cathodes, which cause performance loss and even a safety hazard, are a critical challenge in Ni-rich cathodes during long-term cycling.
Microfluidic rheology of methylcellulose solutions in hyperbolic contractions and the effect of salt in shear and extensional flows
Authors: Micklavzina Benjamin L. , Metaxas Athena E. , Dutcher Cari S.
Published: May 2020

The addition of NaCl to methylcellulose solutions increases the extensional viscosity, which can be measured quantitatively using hyperbolic microfluidic contractions. Fluid stresses during flow can be visualizedviabirefringence.
Self-assembly of linear diblock copolymers in selective solvents: from single micelles to particles with tri-continuous inner structures
Authors: Ye Xianggui , Khomami Bamin
Published: May 2020

Large-scale dissipative particle dynamics (DPD) simulations have been performed to investigate the self-assembly of over 20 000 linear diblock copolymer chains in a selective solvent.
Kinetically-arrested single-polymer nanostructures from amphiphilic mikto-grafted bottlebrushes in solution: a simulation study
Authors: Gumus Bahar , Herrera-Alonso Margarita , Ramírez-Hernández Abelardo
Published: May 2020

Molecular bottlebrushes under a rapid quench into a selective solvent can self-assemble into kinetically-arrested nanostructures.
The challenge of forming a fuzzy core in Jupiter
Authors: Müller Simon , Helled Ravit , Cumming Andrew
Published: May 2020

Recent structure models of Jupiter that match Juno gravity data suggest that the planet harbours an extended region in its deep interior that is enriched with heavy elements: a so-called dilute or fuzzy core. This finding raises the question of what possible formation pathways could have lead to such a structure. We modelled Jupiter’s formation and long-term evolution, starting at late-stage formation before runaway gas accretion. The formation scenarios we considered include both primordial composition gradients, as well as gradients that are built as proto-Jupiter rapidly acquires its gaseous envelope. We then followed Jupiter’s evolution as it cools down and contracts, with a particular focus on the energy and material transport in the interior. We find that none of the scenarios we consider lead to a fuzzy core that is compatible with interior structure models. In all the cases, most of Jupiter’s envelope becomes convective and fully mixed after a few million years at most. This is true even when we considered a case where the gas accretion leads to a cold planet, and large amounts of heavy elements are accreted. We therefore conclude that it is very challenging to explain Jupiter’s dilute core from standard formation models. We suggest that future works should consider more complex formation pathways as well as the modelling of additional physical processes that could lead to Jupiter’s current-state internal structure.
Photoevaporation of the Jovian circumplanetary disk
Authors: Oberg N. , Kamp I. , Cazaux S. , Rab Ch.
Published: May 2020

Context.The Galilean satellites are thought to have formed from a circumplanetary disk (CPD) surrounding Jupiter. When it reached a critical mass, Jupiter opened an annular gap in the solar protoplanetary disk that might have exposed the CPD to radiation from the young Sun or from the stellar cluster in which the Solar System formed.

Aims.We investigate the radiation field to which the Jovian CPD was exposed during the process of satellite formation. The resulting photoevaporation of the CPD is studied in this context to constrain possible formation scenarios for the Galilean satellites and explain architectural features of the Galilean system.

Methods.We constructed a model for the stellar birth cluster to determine the intracluster far-ultraviolet (FUV) radiation field. We employed analytical annular gap profiles informed by hydrodynamical simulations to investigate a range of plausible geometries for the Jovian gap. We used the radiation thermochemical code PRODIMOto evaluate the incident radiation field in the Jovian gap and the photoevaporation of an embedded 2D axisymmetric CPD.

Results.We derive the time-dependent intracluster FUV radiation field for the solar birth cluster over 10 Myr. We find that intracluster photoevaporation can cause significant truncation of the Jovian CPD. We determine steady-state truncation radii for possible CPDs, finding that the outer radius is proportional to the accretion rateṀ0.4. For CPD accretion ratesṀ< 10−12M⊙yr−1, photoevaporative truncation explains the lack of additional satellites outside the orbit of Callisto. For CPDs of massMCPD< 10−6.2M⊙, photoevaporation can disperse the disk before Callisto is able to migrate into the Laplace resonance. This explains why Callisto is the only massive satellite that is excluded from the resonance.
Unveiling pure-metal ejecta X-ray emission in supernova remnants through their radiative recombination continuum
Authors: Greco Emanuele , Vink Jacco , Miceli Marco , Orlando Salvatore , Domček Vladimir , Zhou Ping , Bocchino Fabrizio , Peres Giovanni
Published: May 2020

Context. Spectral analysis of X-ray emission from ejecta in supernova remnants (SNRs) is hampered by the low spectral resolution of CCD detectors, which typically creates a degeneracy between the best-fit values of chemical abundances and the plasma emission measure. The combined contribution of shocked ambient medium and ejecta to the emerging X-ray emission further complicates the determination of the ejecta mass and chemical composition. This degeneracy leads to big uncertainties in mass estimates and can introduce a bias in the comparison between the ejecta chemical composition derived from the observations and the yields predicted by explosive nucleosynthesis models.

Aims. We explore the capabilities of present and future spectral instruments with the aim of identifying a spectral feature that may allow us to discriminate between metal-rich and pure-metal plasmas in X-ray spectra of SNRs.

Methods. We studied the behavior of the most common X-ray emission processes of an optically thin plasma in the high-abundance regime. We investigated spectral features of bremsstrahlung, radiative recombination continua (RRC), and line emission, by exploring a wide range of chemical abundances, plasma temperatures, and ionization parameters. We then synthesized X-ray spectra from a state-of-the-art 3D hydrodynamic simulation of Cas A, by using the response matrix from the Chandra ACIS-S charged-coupled device detector and that of the XRISM/Resolve X-ray calorimeter spectrometer.

Results. We found that a bright RRC shows up when the plasma is made of pure-metal ejecta, and a high spectral resolution is needed to actually identify this ejecta signature. We tested and verified the applicability of our novel diagnostic tool and we propose a promising target for the future detection of such spectral feature: the southeastern Fe-rich clump of Cas A.

Conclusions. While there is no way to unambiguously reveal pure-metal ejecta emission with CCD detectors, X-ray calorimeters will be able to pinpoint the presence of pure-metal RRC and to recover correctly absolute mass and the chemical composition of the ejecta, opening a new window on the link between progenitor star, supernova and SNRs.
Transverse coronal loop oscillations excited by homologous circular-ribbon flares
Authors: Zhang Q. M. , Dai J. , Xu Z. , Li D. , Lu L. , Tam K. V. , Xu A. A.
Published: May 2020

Aims. We report our multiwavelength observations of two homologous circular-ribbon flares in active region 11991 on 2014 March 5, focusing on the transverse oscillations of an extreme-ultraviolet (EUV) loop excited by the flares.

Methods. The flares were observed in ultraviolet and EUV wavelengths by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory spacecraft. These flares were also observed in Hα line center by the 1 m New Vacuum Solar Telescope. Soft X-ray fluxes of the flares in 0.5–4 and 1–8 Å were recorded by the GOES spacecraft.

Results. The transverse oscillations are of fast standing kink mode. The first-stage oscillation triggered by the C2.8 flare is decayless with lower amplitudes (310–510 km). The periods (115–118 s) in different wavelengths are nearly the same, indicating coherent oscillations. The magnetic field of the loop is estimated to be 65–78 G. The second-stage oscillation triggered by the M1.0 flare is decaying with larger amplitudes (1250–1280 km). The periods decrease from 117 s in 211 Å to 70 s in 171 Å, implying a decrease of loop length or an implosion after a gradual expansion. The damping time, which is 147–315 s, increases with the period, so that the values of τ/P are close to each other in different wavelengths. The thickness of the inhomogeneous layer is estimated to be ∼0″​​​.45 under the assumption of resonant absorption.

Conclusions. This is the first observation of the excitation of two kink-mode loop oscillations by two sympathetic flares. The results are important to understand the excitation of kink oscillations of coronal loops and hence the energy balance in the solar corona. Our findings also validate the prevalence of significantly amplified amplitudes of oscillations by successive drivers.
Transfer matrix of a truncated cone with viscothermal losses: application of the WKB method
Authors: Ernoult Augustin , Kergomard Jean
Published: May 2020

The propagation in tubes with varying cross section and wall visco-thermal effects is a classical problem in musical acoustics. To treat this aspect, the first method is the division in a large number of short cylinders. The division in short conical frustums with uniform averaged wall effects is better, but remains time consuming for narrow tubes and low frequencies. The use of the WKB method for the transfer matrix of a truncated cone without any division is investigated. In the frequency domain, the equations due to Zwikker and Kosten are used to define a reference result for a simplified bassoon by considering a division in small conical frustums. Then expressions of the transfer matrix at the WKB zeroth and the second orders are derived. The WKB second order is good at higher frequencies. At low frequencies, the errors are not negligible, and the WKB zeroth order seems to be better. This is due to a slow convergence of the WKB expansion for the particular case: the zeroth order can be kept if the length of the missing cone is large compared to the wavelength. Finally, a simplified version seems to be a satisfactory compromise.
Optimal control for controllable stochastic linear systems
Authors: Bi Xiuchun , Sun Jingrui , Xiong Jie
Published: May 2020

This paper is concerned with a constrained stochastic linear-quadratic optimal control problem, in which the terminal state is fixed and the initial state is constrained to lie in a stochastic linear manifold. The controllability of stochastic linear systems is studied. Then the optimal control is explicitly obtained by considering a parameterized unconstrained backward LQ problem and an optimal parameter selection problem. A notable feature of our results is that, instead of solving an equation involving derivatives with respect to the parameter, the optimal parameter is characterized by a matrix equation.
Zero-sum risk-sensitive stochastic differential games with reflecting diffusions in the orthant
Authors: Ghosh Mrinal Kanti , Pradhan Somnath
Published: May 2020

We study zero-sum games with risk-sensitive cost criterion on the infinite horizon where the state is a controlled reflecting diffusion in the nonnegative orthant. We consider two cost evaluation criteria: discounted cost and ergodic cost. Under certain assumptions, we establish the existence of saddle point equilibria. We obtain our results by studying the corresponding Hamilton–Jacobi–Isaacs equations. For the ergodic cost criterion, exploiting the stochastic representation of the principal eigenfunction, we have completely characterized saddle point equilibrium in the space of stationary Markov strategies.
A study of line-plane configuration in the Corona discharge theory
Authors: Wardaya Asep Yoyo , Muhlisin Zaenul , Hudi Alam , Suseno Jatmiko Endro , Nur Muhammad , Kinandana Andi Wibowo , Windarta Jaka
Published: May 2020

Research on corona discharges from plasma generators has been studied using the line-plane configurations (L-PC). The purpose of this study is to calculate the comparison of the level of conformity of the voltage current characteristic curve (I–V) from the simulation results of numerical calculations of the electrode geometry function and the results of experimental data. There is an electrode (electrode 1) in the form of a rectangular plate with a very thin thickness which has a length and width of a and b respectively in an upright position (line configuration). Electrode 1 has a distance of c to electrode 2 which is in a lying position (plane configuration) below the electrode 1. Furthermore, by using variation of c of 2.5 cm, 2.8 cm, 3.1 cm and 3.4 cm, the two electrodes are connected to the plasma generating equipment, thus producing a plasma discharge that comes out of the tip of the electrode 1 towards electrode 2. Research results from all variations of c prove that there is a high degree of suitability between numerical calculations with experimental data by taking the value of the fitting for the sharpness shape factor of k in the area with the largest plasma discharge.
Attitude Calculation Based on Sequential Correction of Gravity Field and Geomagnetic Field
Authors: Liu Mingyong , Guo Jiaojiao , Wang Mengfan , Niu Yun , Wang Lu
Published: May 2020

Aiming at the problems of gyroscope error divergence and magnetometer susceptibility to soft magnetic environment in attitude calculation of unmanned system, a method of attitude calculation based on gravity field and geomagnetic field sequential correction is proposed. In this method, gyroscope output is used to construct the state equation of attitude quaternion, and then the quaternion is sequentially corrected twice by using accelerometer and magnetometer data in order to obtain accurate attitude output. The experimental results show that, compared with the three traditional attitude calculation algorithms, this algorithm can effectively suppress the gyroscope drift error and improve the attitude output accuracy under the environment of magnetic interference. The static accuracy of the attitude angle is not greater than that of the dynamic accuracy, which meets the application requirements of the unmanned system.
MIMO Sonar DOA Estimation with Joint Matched-Filtering Based on Transmission Diversity Smoothing
Authors: Fan Kuan , Sun Chao , Liu Xionghou , Jiang Guangyu
Published: May 2020

There is a class of methods based on transmission diversity smoothing by multiple-input multiple-output(MIMO) sonar called MIMO-TDS which is considered as one of the most effective methods for estimation of direction-of-arrival(DOA) using MIMO sonar systems. MIMO-TDS produced by orthogonal signal transmission for active sonar can be immediately implemented with high resolution algorithms such as MVDR to estimate the direction of received signals. However, the orthogonal transmission mode of MIMO-TDS is doomed to a loss of transmission array gain indirectly leading to the problem that the echoes are not equipped with as high SNR as enough for an accurate target localization, especially in scenarios in which the targets are far away from array. In order to solving the "low SNR" problem, a solution using all transmitted signals simultaneously to design a joint matched-filter intended for received signal is proposed to improve the performance of MIMO-TDS, which is inspired by the match-filtering concept of "MIMO sonar virtual array method" simplified as MIMO-VA. And accordingly, the unit impulse response function of proposed joint matched-filter is the equivalent of linear sum of all orthogonal transmitted signals and the modified MIMO-TDS is named as "joint matched-filtering MIMO sonar transmission diversity smoothing DOA estimation method", which could be simplified as MIMO-TDS-MF. The characteristic of proposed method is analyzed theoretically and compared to MIMO-TDS and MIMO-VA in this paper:Compared with MIMO-TDS, the proposed method not only retains the advantage of transmission diversity smoothing but also improves the SNR by joint match-filtering; What's more, compared with MIMO-VA, MIMO-TDS-MF is equipped with substantially less computation than the former due to an employment of much fewer matched-filters and is in possession of a superior robustness to that of MIMO-VA. Numerical experiments demonstrate the efficiency of proposed MIMO-TDS-MF.
Iterative Sparse Covariance Matrix Fitting Direction of Arrival Estimation Method Based on Vector Hydrophone Array
Authors: Wand Weidong , Zhang Qunfei , Shi Wentao , SHI Juan , Tan Weijie , Wang Xuhu
Published: May 2020

Aiming at the direction of arrival (DOA) estimation of coherent signals in vector hydrophone array, an iterative sparse covariance matrix fitting algorithm is proposed. Based on the fitting criterion of weighted covariance matrix, the objective function of sparse signal power is constructed, and the recursive formula of sparse signal power iteration updating is deduced by using the properties of Frobenius norm. The present algorithm uses the idea of iterative reconstruction to calculate the power of signals on discrete grids, so that the estimated power is more accurate, and thus more accurate DOA estimation can be obtained. The theoretical analysis shows that the power of the signal at the grid point solved by the present algorithm is preprocessed by a filter, which allows signals in specified directions to pass through and attenuate signals in other directions, and has low sensitivity to the correlation of signals. The simulation results show that the average error estimated by the present method is 39.4% of the multi-signal classification high resolution method and 73.7% of the iterative adaptive sparse signal representation method when the signal-to-noise ratio is 15 dB and the non-coherent signal. Moreover, the average error estimated by the present method is 12.9% of the iterative adaptive sparse signal representation method in the case of coherent signal. Therefore, the present algorithm effectively improves the accuracy of target DOA estimation when applying to DOA estimation with highly correlated targets.
Study on Safety Analysis Method to Task Process of Civil Aircraft Weather Radar System
Authors: Niu Haotian , Ma Cunbao , Han Pei , Sun Xiaoyan
Published: May 2020

To solve the task-process-safety problem of airborne weather radar system, a set of case-inspired safety analysis method is proposed based on the STAMP(Systems-Theoretic Accident Model and Process). Taking weather radar system's task process in approaching stage as an example, a hierarchical control structure is constructed to identify unsafe control actions during the task process, and analyze the potential hazard causes associating with unsafe control actions. Then a safe flight control structure model is constructed and the accident case of Delta Airlines is analyzed to optimize the model. The safety of system task process is improved through putting forward the safe constraints which can control the propagation mechanism of accident. It is indicated through the above analysis that the method can comprehensively identify the potential hazard causes of system, and provide technical support for the safety design of airborne weather radar system.
Numerical Study on the Effect of Thermocouple Mounting Coating on Temperature Measurement of Nozzle Guide Vane
Authors: Guan Peng , Ai Yanting , Xu Yi , Zhao Ming , Tian Jing
Published: May 2020

To analyze the measurement error of thermocouple covered by mounting coating, which is mainly used in air-engine nozzle guide vane temperature test, a mathematical model of the temperature measurement structure was established referring to Mark Ⅱ nozzle guide vane. Based on the heat-flow coupling theory and conjugate heat transfer analysis, the Navier-Stokes equations and heat transfer problem were solved by using SST γ-θ turbulence model. The effects of coating position, coating thickness and coating edge fillet on the temperature of test positions were investigated, respectively. From this study, we find that the temperature predicted by SST γ-θ turbulence model well caters for the test data. The maximum error between calculation and test result is less than 10%. When the leading edge coating is near to the transition point of the suction side, the temperature error will increase. Comparing with that on the middle surface of the pressure side and the leading surface of the suction side, the thermocouple coating has slight effect on the temperature measurement accuracy of the middle surface and the trailing surface of the suction side. If the coating thickness is less than the total temperature boundary layer thickness, the measurement accuracy is almost unaffected. To apply a fillet to the leading edge of thermocouple coating is an effective method to improve the measurement accuracy.
A Balanced Task-Personnel Matching Method for Aircraft Assembly Coordination Planning
Authors: Wei Ming , Tian Xitian , Geng Junhao , Zhang Min
Published: May 2020

To solve the problem of unbalanced matching between planning task and personnel in aircraft assembly coordination process planning under collaborative planning mode, a balanced matching method based on comprehensive consideration of task granularity, task equilibrium degree was proposed. By analyzing the characteristics of aircraft digital assembly coordination process planning and personnel capability attributes, the evaluation matrix of planning task and personnel was builded based on fuzzy linguistic variables. Finally, the evaluation matrix was solved to achieve the balanced matching between planning task and personnel. The feasibility and effectiveness of proposed method were verified by an aircraft tail of assembly coordination process planning task and personnel example-matching.
Dataflow Feature Analysis for Industrial Networks Communication Security
Authors: Zhang Dinghua , Hu Yibo , Cao Guoyan , Liu Yong , Shi Yuanbing , Huang Minghao , Pan Quan
Published: May 2020

The autonomous security situation awareness on industrial networks communication has been a critical subject for industrial networks security analysis. In this paper, a CNN-based feature mining method for networks communication dataflow was proposed to intrusion detect industrial networks to extract security situation awareness. Specifically, a normalization technique uniforming different sorts of networks dataflow features was designed for dataflow features fusion in the proposed feature mining method. The proposed methods were used to detect the security situation of traditional IT networks and industrial control networks. Experiment results showed that the proposed feature analysis method had good transferability in the two network data, and the accuracy rate of network anomaly detection was ideal and had higher stability.
A Strategy of Data Synchronization in Distributed System with Read Separating from Write
Authors: Gao Jintao , Liu Wenjie , Li Zhanhuai
Published: May 2020

Read separating from write is a strategy that NewSQL adopts to incorporate the advantages of traditional relation database and NoSQL database. Under this architecture, baseline data is split into multiple partitions stored at distributed physical nodes, while delta data is stored at single transaction node. For reducing the pressure of transaction node and improving the query performance, delta data needs to be synchronized into storage nodes. The current strategies trigger the procedure of data synchronization per partition, meaning that unchanged partitions will also participate in data synchronization, which consumes extra network cost, local IO and space resources. For improving the efficiency of data synchronization meanwhile mitigating space utilization, the fine-grained data synchronization strategy is proposed, whose main idea includes that fine-grained logical partitions upon original coarse-grained partitions is established, providing more correct synchronized unit; the delta data sensing strategy is introduced, which records the mapping between changed partitions and its delta data; instead of partition driven, the data synchronization through the delta-broadcasting mechanism is driven, constraining that only changed partitions can participate in data synchronization. The fine-grained data synchronization strategy on Oceanbase is implemented, which is a distributed database with read separating from write, and the results show that our strategy is better than other strategies in efficiency of data synchronizing and space utilization.
First cases of Angiostrongylus cantonensis infection reported in Martinique, 2002–2017
Authors: Dard Céline , Tessier Eve , Nguyen Duc , Epelboin Loïc , Harrois Dorothée , Swale Christopher , Cabié André , de Meuron Katia , Miossec Charline , Desbois-Nogard Nicole
Published: May 2020

Neuroangiostrongyliasis is a parasitic disease caused by the accidental ingestion of the nematode Angiostrongylus cantonensis in its larval form. Human infection can lead to eosinophilic meningitis, sometimes complicated by life-threatening radiculomyelitis or encephalitis. Although some cases have been reported from other Caribbean Islands, no cases have been diagnosed in Martinique so far. Here, we report the first eight laboratory-confirmed cases of neuroangiostrongyliasis on the island of Martinique, French West Indies, between 1 January 2002 and 31 December 2017. One case was fatal and five resulted in neurological sequelae. The medical community should consider the risk of A. cantonensis infection in patients living in or returning from Martinique.
Interkulturelles Personalmanagement im ärztlichen Bereich
Authors: Klüter Harald , Bachner Ingeborg
Published: May 2020

Der Anteil in Deutschland tätiger ausländischer Ärzte steigt an. In 2018 betrug der Zuwachs 3500 und insgesamt waren annähernd 55 000 Ärztinnen und Ärzte aus dem Ausland in deutschen Kliniken beschäftigt 1. Berücksichtigt man den demografischen Wandel und die zunehmende Zahl an altersbedingten Austritten in den Ruhestand wird zukünftig etwa jeder 4. bis 5. im Krankenhaus tätige Arzt aus dem Ausland stammen. In die ausländischen Ärzte muss zu Beginn ihrer Tätigkeit am neuen Arbeitsort in Deutschland auf vielfältige Weise zur beruflichen Qualifizierung investiert werden. Ein interkulturell ausgerichtetes Personalmanagement im Krankenhaus ist nötig, um die rekrutierten Kräfte in ihrer ärztlichen Rolle weiterzuentwickeln und zu binden.
Nierenersatztherapie auf der Intensivstation
Authors: Kielstein Jan T. , Eden Gabriele
Published: May 2020

Die akute Nierenschädigung tritt heute vor allem bei Intensivpatienten nach großen operativen Eingriffen, mit Sepsis oder im Rahmen des Versagens eines oder mehrerer anderer Organe auf. Intensivpatienten, die einer Nierenersatztherapie bedürfen, haben eine Krankenhausmortalität von ca. 60 %. Der Zeitpunkt des Beginns der Nierenersatztherapie ist Gegenstand zahlreicher Studien gewesen. Zu den hartnäckigsten Legenden in der Medizin zählt jene zum Harnstoff-Schwellenwert, der die Notwendigkeit einer Nierenersatztherapie anzeigen soll. Zwei rezente Arbeiten zeigen, dass allein ein durch den Laborwert getriggerter Dialysebeginn, z. B. Erfüllung der AKIN-3-Kriterien, dazu führt, dass knapp die Hälfte der Patienten eine Dialysetherapie bekommen, die sie nicht benötigt. Bezüglich der Dosis der Nierenersatztherapie konnte eine Meta-Analyse belegen, dass neben einem fehlenden Vorteil einer hohen Intensität der Nierenersatztherapie auf die Mortalität sogar die Wiederaufnahme der Nierenfunktion verzögert wird. Unter der hohen Dosis der heutzutage eingesetzten Nierenersatzverfahren kommt es auch zur vermehrten Elimination von Elektrolyten, Nährstoffen und Antibiotika, denn die Anpassung von Antibiotika an die Intensität der Nierenersatztherapie ist schwierig. Für die Behandlung der akuten Nierenschädigung stehen mehrere Nierenersatzverfahren zur Verfügung: die klassische intermittierende Hämodialyse, die kontinuierliche Nierenersatztherapie (CVVH), die verlängerte tägliche Dialyse (PIRRT/SLED/GENIUS-Dialyse) und die Peritonealdialyse. Trotz intensiver Forschungsbemühungen in diesem Gebiet gibt es bisher keine Studie, die die Überlegenheit eines dieser Verfahren in Bezug auf die Mortalität oder renale Endpunkte wie z. B. die Wiederaufnahme der Nierenfunktion belegen. Gegenwärtig gibt es auch keinen Konsens bezüglich der Kriterien für die Beendigung der Nierenersatztherapie. Die Menge des Urins scheint jedoch ein guter Parameter zu sein, auch die Höhe des Kreatininanstieges in der RRT-Pause (RRT: renal replacement therapy) oder die 6-h-Kreatininclearance eignen sich als Prädiktor für den erfolgreichen Auslass der Nierenersatztherapie.
The Effects of Agility Ladders on Performance: A Systematic
Review
Authors: Afonso José , da Costa Israel Teoldo , Camões Miguel , Silva Ana , Lima Ricardo Franco , Milheiro André , Martins Alexandre , Laporta Lorenzo , Nakamura Fábio Yuzo , Clemente Filipe Manuel
Published: May 2020

The goal of this systematic review was to evaluate the effects of exercise programs using
agility ladders and to assess the quality of available evidence. Search was conducted in
October of 2019 using the following databases: Cochrane Library, PEDro, PubMed, Scopus and Web
of Science. Study eligibility criteria included randomized trials or randomized controlled
trials using agility ladders drills. Participants were healthy humans of any health status. The
study appraisal and synthesis methods followed the revised Cochrane risk-of-bias tool for
randomized trials (RoB 2) and a qualitative synthesis of the main results of each study were
applied. Only five studies met our criteria, lasting between 4 and 8 weeks. Only two studies
evaluated the effects of ladder drills on more than one dimension. Lack of description of the
specific exercises that were used limits reproducibility of current studies. With one
exception, the articles had low risk of bias for most domains. Despite the widespread
popularity of agility ladder drills, research is scarce and problematic, with poorly described
protocols and mostly unidimensional performance measures. Claims that agility ladders improve
agility and other physical skills is premature, given the nature and quality of existing
research.
Creation of 4-Quinolone Thioether and Selenoether Derivatives via Pd-NHC Catalysed Cross-Coupling Reaction
Authors: Das Sajal , Ghosh Prasanjit
Published: May 2020

Pd-NHC catalysed direct sulfenylation and selenylation of 3-iodo-4-quinolones has been developed. This protocol provides an alternative route for the construction of ipso-C–S and C–Se bond formation in 4-quinolones under aerobic conditions.
Ruthenium-Catalyzed Synthesis of Pyrrolo[1,2-a]quinoxaline Derivatives from 1-(2-Aminophenyl)pyrroles and Sulfoxonium Ylides
Authors: Huang Guo-Sheng , Cui Xin-Feng , Hu Fang-Peng , Zhou Xiao-Qiang , Zhan Zhen-Zhen
Published: May 2020

A ruthenium-catalyzed [5+1] annulation of 1-(2-aminophenyl)pyrroles with α-carbonyl sulfoxonium ylides is reported. This reaction provides a one-step method for synthesizing pyrrolo[1,2-a]quinoxaline derivatives under ambient conditions. The system proceeds with a short reaction time and a high functional-group tolerance. Notably, this divergent protocol tolerates β-keto sulfoxonium ylides and can be applied to α-ester sulfoxonium ylides. A preliminary study was made of the mechanism of the reaction, and a reaction pathway is proposed.
Anti-Inflammatory Effect of Musa acuminata Stem
Authors: Apriasari Maharani Laillyza , Pramitha Selviana Rizky , Puspitasari Dewi , Ernawati Diah Savitri
Published: May 2020

Objective This study was designed to assess the anti-inflammatory effect of Musa acuminata through the expression of tumor necrosis factor-α (TNF-α) and nuclear factor kappa β (NF-κB) after 3 days of application of Musa acuminata stem extract (MASE) gel on oral mucosal wound.

Materials and Methods An experimental study with post-test only control group design was conducted. Twenty male Rattus norvegicus (Wistar) were injured on their left buccal mucosa and treated three times a day with MASE gel of varying concentrations: 0% (as control), MASE 25%, MASE 37.5%, and MASE 50%. On day 3, a biopsy was performed on each mucosal wound for later immunohistochemical analysis for the expressions of TNF-α and NF-κB.

Results The highest expression of TNF-α was observed in the control group (13.20 ± 1.79), while the lowest was in the treatment group using 50% MASE (6.40 ± 1.14). Meanwhile the comparison between treatment groups did not highlight any significant difference (p > 0.05). The highest expression of NF-κB was observed in the control group (13.20 ± 1.30), whereas the lowest was in the treatment group using MASE 50% (6.40 ± 1.14). NF-κB was significantly lower in the treatment group using MASE 50% when compared with other treatment groups (p < 0.05).

Conclusion Application of MASE on mucosal wound reduces the expression of TNF-α and NF-κB at all concentrations. The anti-inflammatory effect of MASE 50% was the strongest one.
Severe Bilateral Cervical Lymphadenomegaly Associated with Ethosuximide
Authors: Montenegro Maria Augusta , Cardinalli Izilda A. , Daiggi Camila Maia Martin
Published: May 2020

Lymphadenomegaly associated with antiepileptic drugs is well documented; however, severe lymphadenopathy mimicking a neoplasm is a rare adverse event associated with antiepileptic drugs. It is usually characterized by a large cervical mass associated with fever, weight loss, skin rash, and abnormal complete blood count (atypical lymphocytes, eosinophilia, and abnormal neutrophil count). In this case report, we described a child with severe bilateral cervical lymphadenomegaly associated with ethosuximide, in which excisional biopsy of the enlarged nodes was needed to establish the final diagnosis. Prognosis was excellent after drug discontinuation.
Telehealth for High-Risk Pregnancies in the Setting of the COVID-19 Pandemic
Authors: Aziz Aleha , Zork Noelia , Aubey Janice J. , Baptiste Caitlin D. , D'Alton Mary E. , Emeruwa Ukachi N. , Fuchs Karin M. , Goffman Dena , Gyamfi-Bannerman Cynthia , Haythe Jennifer H. , LaSala Anita P. , Madden Nigel , Miller Eliza C. , Miller Russell S. , Monk Catherine , Moroz Leslie , Ona Samsiya , Ring Laurence E. , Sheen Jean-Ju , Spiegel Erica S. , Simpson Lynn L. , Yates Hope S. , Friedman Alexander M.
Published: May 2020

As New York City became an international epicenter of the novel coronavirus disease 2019 (COVID-19) pandemic, telehealth was rapidly integrated into prenatal care at Columbia University Irving Medical Center, an academic hospital system in Manhattan. Goals of implementation were to consolidate in-person prenatal screening, surveillance, and examinations into fewer in-person visits while maintaining patient access to ongoing antenatal care and subspecialty consultations via telehealth virtual visits. The rationale for this change was to minimize patient travel and thus risk for COVID-19 exposure. Because a large portion of obstetric patients had underlying medical or fetal conditions placing them at increased risk for adverse outcomes, prenatal care telehealth regimens were tailored for increased surveillance and/or counseling. Based on the incorporation of telehealth into prenatal care for high-risk patients, specific recommendations are made for the following conditions, clinical scenarios, and services: (1) hypertensive disorders of pregnancy including preeclampsia, gestational hypertension, and chronic hypertension; (2) pregestational and gestational diabetes mellitus; (3) maternal cardiovascular disease; (4) maternal neurologic conditions; (5) history of preterm birth and poor obstetrical history including prior stillbirth; (6) fetal conditions such as intrauterine growth restriction, congenital anomalies, and multiple gestations including monochorionic placentation; (7) genetic counseling; (8) mental health services; (9) obstetric anesthesia consultations; and (10) postpartum care. While telehealth virtual visits do not fully replace in-person encounters during prenatal care, they do offer a means of reducing potential patient and provider exposure to COVID-19 while providing consolidated in-person testing and services.

Key Points
An apparatus to synthesize ceramic nanoparticles with a precisely adjusted temperature history and a significant mass output
Authors: Rasche David B. , Tigges Lena , Schmid Hans-Joachim
Published: May 2020

For gas phase nanoparticle production, hot wall reactors are widely used. In this article, we will describe the fundamental design considerations for a hot wall reactor system able to produce oxide nanoparticles. The system is outstanding in its ability to produce mostly spherical nanoparticles at particle sizes of up to 100 nm and even larger at mass outputs in the order of grams per hour by being able to rapidly quench the aerosol. While high production rates or larger particle sizes are already easily obtained with hot wall reactors, it is very challenging to produce these spherical particles at high mass rates. We will show in this research that the temperature and the particle number concentration are the major aspects influencing the particle morphology at the end of the process. Investigation on the performance of the setup shows good control over the temperature and the particle production stability. A representative particle characterization using SEM and scanning mobility particle sizer showed that particles are mostly spherical, while the particle size distribution had a geometric standard deviation close to 1.5. In addition to the aspects mentioned above, a possibility to manipulate the aggregation downstream of the reactor is to be presented as well. We found that applying electrical charges to the aerosol particles (in opposite polarity) can significantly foster aggregation.
Results from a new flowing liquid Li limiter with TZM substrate during high confinement plasmas in the EAST device
Authors: Zuo G. Z. , Li C. L. , Maingi R. , Meng X. C. , Sun Z. , Xu W. , Qian Y. Z. , Huang M. , Tang Z. L. , Zhang D. H. , Zhang L. , Chen Y. J. , Mao S. T. , Wang Y. M. , Zhao H. L. , Andruczyk D. , Tritz K. , Gong X. Z. , Hu J. S. ,   EAST Team
Published: May 2020

A third generation flowing liquid lithium (FLiLi) limiter with a substrate made of TZM, an alloy with >99% Mo, was fabricated by conventional manufacturing techniques. TZM has a high corrosion resistance, a high sputtering threshold, and a good wettability to Li, as compared to stainless steel (SS), which had been used as an FLiLi substrate surface in 2014 and 2016. The third generation FLiLi was inserted into the edge in EAST H-mode plasmas in an upper single-null configuration with an ion grad-B drift toward the upper divertor with a limiter temperature of 330–380 °C and an auxiliary heating power of about 2–8 MW. Analysis has shown that by using TZM FLiLi, fuel particle recycling continuously decreased and near-complete edge localized mode elimination was achieved in H-mode plasmas with RF-only heating. The main impurities during the initial FLiLi discharges were Mo, Fe, and W resulting from strong plasma interaction at the Mo plate side, the SS collector, and the upper W divertor. Plasma stored energy increased by about 10 kJ in subsequent FLiLi discharges due to decreased impurity radiation. Engineering analysis shows a uniform lithium flow with an ∼80% Li coverage ratio on the limiter surface, similar to the second FLiLi, even though only one of two J × B pumps was functioning. Despite technical difficulties, the FLiLi gen.3 improved the overall plasma performance, providing support for flowing liquid Li plasma facing component applications in present and future devices.
An induction voltage adder with MHz repetition rates and nanosecond duration based on printed circuit board stacked Blumlein lines
Authors: Shen Yi , Ye Mao , Wang Wei , Liu Yi , Huang Ziping , Zhang Huang , Xia Liansheng , Long Jidong
Published: May 2020

By utilizing the radio-frequency metal-oxide-semiconductor field-effect transistor switch, the multi-stage stacked printed circuit board Blumlein lines, and the induction voltage adder, a voltage generator with MHz repetition rates and nanosecond duration was designed and fabricated. The shunting current of the multi-stage stacked Blumlein lines, which consists of the coupling current at the load ends and the leakage current at the switch ends, is clarified. The circuit simulation and experiment of the three-stage stacked Blumlein lines are carried out; the result shows that the experiment and simulation agree well. The five-stage IVA prototype is designed for generating voltage pulses of ∼10 kV in amplitude and 8–11 ns in duration with MHz burst repetition rates. The voltage generator with MHz repetition rates and nanosecond duration demonstrated an important application prospect to reduce the electron beam initial emittance of the high energy accelerator.
Fluorescence strategies for mapping cell membrane dynamics and structures
Authors: Sankaran Jagadish , Wohland Thorsten
Published: May 2020

Fluorescence spectroscopy has been a cornerstone of research in membrane dynamics and organization. Technological advances in fluorescence spectroscopy went hand in hand with discovery of various physicochemical properties of membranes at nanometric spatial and microsecond timescales. In this perspective, we discuss the various challenges associated with quantification of physicochemical properties of membranes and how various modes of fluorescence spectroscopy have overcome these challenges to shed light on the structure and organization of membranes. Finally, we discuss newer measurement strategies and data analysis tools to investigate the structure, dynamics, and organization of membranes.
Eulerian CFD model of direct absorption solar collector with nanofluid
Authors: Bårdsgård R. , Kuzmenkov D. M. , Kosinski P. , Balakin B. V.
Published: May 2020

Solar energy is the most promising source of renewable energy. However, the solar energy harvesting process has relatively low efficiency, while the practical use of solar energy is challenging. Direct absorption solar collectors (DASC) have been proved to be effective for a variety of applications. In this article, a numerical study of a nanofluid direct absorption solar collector was performed using computational fluid dynamics (CFD). A rectangular DASC with incident light on the top surface was simulated using an Eulerian–Eulerian two-phase model. The model was validated against experiments. A number of parameters such as collector height, particle concentration, and bottom surface properties were optimized. Considering particle concentration, we observed that the optimum volume fraction of particles for enhancing efficiency was obtained for 0.3 wt. %, and a decrease in efficiency was observed for ≥0.5 wt. %. Design recommendations based on the numerical analysis were provided. The optimum configuration of the considered collector reaches the best efficiency of 68% for 300 μm thickness of the receiver and the highest total efficiency is 87% at a velocity of 3 cm/s. The thermal destabilization of the nanofluid was studied. It was found that over 10% of the nanoparticles are captured in the collector.
Dynamics of seeded blobs under the influence of inelastic neutral interactions
Authors: Thrysøe A. S. , Naulin V. , Nielsen A. H. , Juul Rasmussen J.
Published: May 2020

Field-aligned filaments, the so-called blobs, born at the edge of the magnetically confined region of tokamaks propagate radially outward into the scrape-off layer (SOL) region that allows for a substantial population of neutral particles compared to the region of confinement. The electrons and ions constituting the blob undergo both elastic and inelastic collisions with the neutral particles, and the latter leads to sources and sinks of the blob density, momentum, and heat. The influence of the inelastic collisions with neutrals on the evolution of seeded blobs is investigated numerically by the nHESEL drift-fluid model through a series of discrete scans in interactions, active source terms, and blob plasma parameters. In light of the results, the potential influence of local inelastic collisions on the SOL density shoulder formation is discussed. It is found that density sources increase the blob compactness, which delays the blob dispersion and decreases the dispersion rate. Density sources or momentum sinks also influence the blob dynamics by increasing the vorticity layer around the perturbation, whereas the pressure sources/sinks only affect the blob dynamics marginally. The change to the vorticity structure leads, in most cases, to a decrease in the radial velocity of the blob center of mass, although, at high source rates, a radial acceleration of the blob center of mass is also observed. Density sources may, thus, contribute to shoulder formation not only by increasing the density locally but also by changing the filament dynamics.