bluuebunny/crossref_metadata_2025 huggingface dataset:
Bilateral Cochlear Implants Allow Listeners to Benefit from Visual Information When Talker Location is Varied
Authors: Dorman Michael F. , Natale Sarah , Knickerbocker Alissa
Published: April 2020

Background Previous research has found that when the location of a talker was varied and an auditory prompt indicated the location of the talker, the addition of visual information produced a significant and large improvement in speech understanding for listeners with bilateral cochlear implants (CIs) but not with a unilateral CI. Presumably, the sound-source localization ability of the bilateral CI listeners allowed them to orient to the auditory prompt and benefit from visual information for the subsequent target sentence.

Purpose The goal of this project was to assess the robustness of previous research by using a different test environment, a different CI, different test material, and a different response measure.

Research Design Nine listeners fit with bilateral CIs were tested in a simulation of a crowded restaurant. Auditory–visual (AV) sentence material was presented from loudspeakers and video monitors at 0, +90, and −90 degrees. Each trial started with the presentation of an auditory alerting phrase from one of the three target loudspeakers followed by an AV target sentence from that loudspeaker/monitor. On each trial, the two nontarget monitors showed the speaker mouthing a different sentence. Sentences were presented in noise in four test conditions: one CI, one CI plus vision, bilateral CIs, and bilateral CIs plus vision.

Results Mean percent words correct for the four test conditions were: one CI, 43%; bilateral CI, 60%; one CI plus vision, 52%; and bilateral CI plus vision, 84%. Visual information did not significantly improve performance in the single CI conditions but did improve performance in the bilateral CI conditions. The magnitude of improvement for two CIs versus one CI in the AV condition was approximately twice that for two CIs versus one CI in the auditory condition.

Conclusions Our results are consistent with previous data showing the large value of bilateral implants in a complex AV listening environment. The results indicate that the value of bilateral CIs for speech understanding is significantly underestimated in standard, auditory-only, single-speaker, test environments.
Speech Perception and Sound-Quality Rating with an Adaptive Nonlinear Frequency Compression Algorithm in Mandarin-Speaking Hearing Aid Users
Authors: Xu Li , Voss Solveig C. , Yang Jing , Wang Xianhui , Lu Qian , Rehmann Julia , Kuehnel Volker , Qian Jinyu
Published: April 2020

Abstract Background Mandarin Chinese has a rich repertoire of high-frequency speech sounds. This may pose a remarkable challenge to hearing-impaired listeners who speak Mandarin Chinese because of their high-frequency sloping hearing loss. An adaptive nonlinear
frequency compression (adaptive NLFC) algorithm has been implemented in contemporary hearing aids to alleviate the problem. Purpose The present study examined the performance of speech perception and sound-quality rating in Mandarin-speaking hearing-impaired listeners using
hearing aids fitted with adaptive NLFC (i.e., SoundRecover2 or SR2) at different parameter settings. Research Design Hearing-impaired listeners' phoneme detection thresholds, speech reception thresholds, and sound-quality ratings were collected with various SR2 settings.
Study Sample The participants included 15 Mandarin-speaking adults aged 32 to 84 years old who had symmetric sloping severe-to-profound sensorineural hearing loss. Intervention The participants were fitted bilaterally with Phonak Naida V90-SP hearing aids. Data
Collection and Analysis The outcome measures included phoneme detection threshold using the Mandarin Phonak Phoneme Perception test, speech reception threshold using the Mandarin hearing in noise test (M-HINT), and sound-quality ratings on human speech in quiet and noise, bird chirps,
and music in quiet. For each test, five experimental settings were applied and compared: SR2-off, SR2-weak, SR2-default, SR2-strong 1, and SR2-strong 2. Results The results showed that listeners performed significantly better with SR2-strong 1 and SR2-strong 2 settings than
with SR2-off or SR2-weak settings for speech reception threshold and phoneme detection threshold. However, no significant improvement was observed in sound-quality ratings among different settings. Conclusions These preliminary findings suggested that the adaptive NLFC algorithm
provides perceptual benefit to Mandarin-speaking people with severe-to-profound hearing loss.
Die neue Rolle des Einkäufers: „Einkäufer müssen mit dem Spagat zwischen Möglichem und Finanzierbarem umgehen können“
Authors: Rößing Sabine
Published: April 2020

Der Einkauf wandelt sich vom effizienten Dienstleister zum strategischen Projektplaner. Dabei arbeiten sich die reinen Beschaffungsexperten von einst in neue Geschäftsfelder vor.
Sicht des Industriepartners: Außendienstmitarbeiter der Industrie und Klinikeinkäufer müssen vermehrt interdisziplinär auftreten
Authors: Rößing Sabine
Published: April 2020

Björn Fuchs, Strategischer Key Account Manager Deutschland bei Edwards Life Sciences Deutschland, bringt die Sichtweise der Industrie auf den Klinikeinkauf ein. Denn Win-Win-Situationen entstehen nur durch eine gute Zusammenarbeit.
Schulungen von Einkäufern: Wirksamkeit von Verhandlungstrainings – Wunschvorstellung oder Wirklichkeit?
Authors: Schlüchtermann Jörg , Rolf Philipp
Published: April 2020

Das breite Angebot an Verhandlungstrainings zeugt indirekt von einer großen Nachfrage – und viele Arbeitgeber werben für sich mit entsprechenden Fortbildungsangeboten. Nicht unumstritten ist allerdings, ob derartige Trainings auch das einhalten können, was sie versprechen. Zur Beantwortung dieser Frage beschreibt der vorliegende Beitrag einen nachvollziehbaren Analyserahmen für Trainingswirksamkeit und würdigt darauf aufbauend den aktuellen Forschungsstand zur Wirksamkeit von Verhandlungstrainings kritisch.
Beschaffung medizinischer Geräte und Verbrauchsmaterialien: Neue Gestaltungsspielräume des Ver gaberechts in Zeiten der Corona-Krise
Authors: Langenbach Isabel
Published: April 2020

Das Corona-Virus stellt für Kliniken nicht nur eine medizinische Herausforderung dar. Hinzu kommen Engpässe bei der Lieferung medizinischen Verbrauchmaterials (z. B. Schutzkleidung und Hygienemittel) oder medizinischer Geräte. Bei der Deckung des alltäglichen Bedarfs im Klinikbetrieb kommt auf (öffentliche) Kliniken, die an das Vergaberecht gebunden sind, eine Welle vergabe- und vertragsrechtlicher Fragen zu.
Neue zentrale Kommunikationsplattform: femak-Forum geht online!
Authors: Merkel Martin
Published: April 2020

Sehr geehrte Damen und Herren, liebe Kolleginnen und Kollegen,
Near-zero temperature coefficient of resistivity in LaFe9.45Al3.55 compound over 5–300 K
Authors: Wang Hao , Huang Rongjin , Huang Chuanjun , Guo Shibin , Song Yuzhu , Chen Jun , Li Laifeng
Published: April 2020

The temperature coefficient of resistivity (TCR) was systematically investigated in La (Fe, Al)13 compounds with an Al atomic content from 3.40 to 3.70. We find that the local extremum of the TCR is obtained in LaFe9.45Al3.55, which is −20.914 ppm/K over 5–300 K. It is rare for TCR to stay at such a low level over such a wide temperature range below 300 K. Our work revealed that all compounds remain the same structure of cubic NaZn13-type (space group: Fm3¯c) based on synchrotron radiation X-ray diffraction (SR-XRD) and X-ray powder diffraction (XRD) tests. The magnetization–temperature curves indicate that all samples are ferromagnet. We analyzed the effect of structure on the performance from the perspective of the Fe–Fe atomic distance. These peculiar behaviors are possibly due to the competitive effect by magnetic scattering and e–p scattering.
Anisotropic magnetic response of Weyl semimetals in a topological insulator multilayer
Authors: Aftab Tayyaba , Sabeeh Kashif
Published: April 2020

Magnetic susceptibility of Weyl semimetals, placed in a tilted magnetic field, is studied. Weyl semimetals have three contributions: spin, orbital, and spin–orbital; all three contributions are investigated for a tilted magnetic field. We find that spin susceptibility at a low temperature varies linearly with the Fermi energy and is oscillatory function of tilt angle; the orbital part shows diamagnetic divergence at the zero Fermi energy like graphene, and spin–orbital contribution is an even function of the Fermi energy and the tilt angle. Due to the anisotropic nature of the magnetic response, we propose that spin, orbital, and spin–orbital magnetic response can be distinguished by changing the orientation of the applied magnetic field.
A perpendicular graphene/ferromagnet electrode for spintronics
Authors: Naganuma H. , Zatko V. , Galbiati M. , Godel F. , Sander A. , Carrétéro C. , Bezencenet O. , Reyren N. , Martin M.-B. , Dlubak B. , Seneor P.
Published: April 2020

We report on the large-scale integration of graphene layers over a FePd perpendicular magnetic anisotropy (PMA) platform, targeting further downscaling of spin circuits. An L10 FePd ordered alloy showing both high magneto-crystalline anisotropy and a low magnetic damping constant, is deposited by magnetron sputtering. The graphene layer is then grown on top of it by large-scale chemical vapor deposition. A step-by-step study, including structural and magnetic analyses by x-ray diffraction and Kerr microscopy, shows that the measured FePd properties are preserved after the graphene deposition process. This scheme provides a graphene protected perpendicular spin electrode showing resistance to oxidation, atomic flatness, stable crystallinity, and perpendicular magnetic properties. This, in turn, opens the way to the generalization of hybrid 2D-materials on optimized PMA platforms, sustaining the development of spintronics circuits based on perpendicular spin-sources as required, for instance, for perpendicular-magnetic random-access memory schemes.
Shallow Si donor in ion-implanted homoepitaxial AlN
Authors: Hayden Breckenridge M. , Guo Qiang , Klump Andrew , Sarkar Biplab , Guan Yan , Tweedie James , Kirste Ronny , Mita Seiji , Reddy Pramod , Collazo Ramón , Sitar Zlatko
Published: April 2020

We demonstrate Si as a shallow donor in aluminum nitride (AlN) with an ionization energy of ∼70 meV. The shallow state was achieved by ion implantation of Si into homoepitaxial AlN and a low thermal budget damage recovery and activation process. These results demonstrate that the DX formation may be a kinetically limited process, though being a non-equilibrium process, preventing the Si donor from relaxing to the deep donor state. The room temperature conductivity was measured to be ∼0.05 Ω−1 cm−1, which is one order of magnitude higher than what has been reported for the epitaxially doped or implanted AlN.
Electrostatic interactions and stability of dusty plasmas and the multicomponent Ornstein–Zernike equation
Authors: Filippov Anatoly V. , Fortov Vladimir E. , Reshetniak Victor V. , Starostin Andrey N. , Tkachenko Igor M.
Published: April 2020

Using the Ornstein–Zernike integral fluid equation for multi-component plasma, the dielectric properties and thermodynamical stability of dusty plasmas are studied. For the most non-ideal dust plasma subsystem, a transition to the one-component approximation is carried out. It is shown that the effective pseudopotential for determining the correlation functions in the selected subsystem should not include the contribution of this subsystem to the screening constant but also take into account the condition of total plasma quasineutrality. It is demonstrated that when the coupling parameter of the dust subsystem is smaller than unity, Γ00 < 1, the interaction potential between the charged plasma particles is fairly well described by the Debye potential with a full screening constant. For Γ00 > 1, the static dielectric function in the long wavelength domain becomes negative, and this domain expands when Γ00 increases. This leads to the appearance of attraction of particles with charges of the same sign and repulsion of particles with charges of the opposite sign. In this case, both the total pressure and the isothermal compressibility in the entire studied range of the coupling parameter Γ00 < 250 remain positive, but the isothermal compressibility of the dust subsystem becomes negative at Γ00 ≈ 2 within the studied range of variation of the plasma parameters. The sign of the derivative of the chemical potential with respect to the total number of dust particles, the positiveness of which is the third condition for the thermodynamic stability, is shown to coincide with the sign of the isothermal compressibility of the dust subsystem. Therefore, it is concluded that the equilibrium dusty plasma at Γ00 > 2 is thermodynamically unstable.
Non-local edge enhanced imaging with incoherent thermal light
Authors: Song Hanquan , Zhang Yingwen , Ren Yuhang , Yuan Zhidan , Zhao Dayu , Zheng Zhiyuan , Gao Lu
Published: April 2020

Spiral phase contrast imaging is an effective technique for the edge enhancement of a phase object. The spiral phase filter is the core component of the system and it provides sensitivity to the phase and amplitude gradients of the object. General spiral phase contrast imaging depends on the 4f imaging system in a single light beam with the coherent light source of visible or infrared wavelengths. Here, we constructed a non-local edge enhanced imaging system using an incoherent thermal light source. The detected object and the adopted spiral phase filter were non-locally placed in two separated light beams. The edge enhanced ghost image of the phase object can then be achieved through second-order intensity correlation measurements. The classical nature of the spatial degree of freedom of our proposed edge enhanced ghost imaging system was also demonstrated through the measurement of Bell-type inequality.
Particle trajectories in pipe flow considering particle–wall collisions
Authors: Wang Jingyu , Huang Wenshi , Zhang Yang , Wu Yuxin , Zhang Hai , Yue Guangxi
Published: April 2020

Particle–wall collision behaviors have strong effects on confined particle-laden pipe flows, which are important in pneumatic conveying and pulverized coal combustion. In this paper, a numerical simulation of a pipe flow was conducted to analyze the effects of different initial conditions and particle–wall collision model parameters. The results show that a realistic collision model with coefficients provided by experiments can predict accurate particle exit velocity distributions. The effects of the initial motion of the particles diminish at the exit as long as the pipe length and the number of wall collisions are sufficient, and larger particles require the length to be longer. A simplified collision model with an arbitrary constant restitution coefficient e and a friction coefficient f leads to inaccurate results of the particle exit velocity probability density function, and using constant coefficients from data of a single collision angle will make the model ineffective. It is better to apply a normal distribution for e and a constant f if available collision data are limited, which gets reasonably accurate statistical results despite small distribution deviations.
Microscopic origin of breakdown of Stokes–Einstein relation in binary mixtures: Inherent structure analysis
Authors: Kumar Shubham , Sarkar Sarmistha , Bagchi Biman
Published: April 2020

Aqueous binary mixtures often exhibit dramatic departure from the predicted hydrodynamic behavior when transport properties are plotted against composition. We show by inherent structure (IS) analysis that this sharp composition dependent breakdown of the Stokes–Einstein relation can be attributed to the non-monotonic variation in the average inherent structure energy of these mixtures. Further IS analysis reveals the existence of a unique ground state, stabilized by both the formation of an optimum number of H-bonds and a favorable hydrophobic interaction at this composition. The surprisingly sharp turnaround behavior observed in the effective hydrodynamic radius also owes its origin to the same combination of these two factors. Interestingly, the temperature dependence of isothermal compressibility shows a minimum at the particular composition. Extensive studies on water–dimethyl sulfoxide and water–ethanol mixtures using two different force-fields of water reveal many features that are nearly universal. A justification of this quasi-universal behavior is provided in terms of a mode-coupling theory (MCT) of viscosity, which can serve as the starting point of a remarkable correlation observed with the nearest neighbor structure, as captured by the first peaks of the radial distribution function, and the slowdown in the intermediate scattering function at intermediate wavenumbers. Therefore, the formation of the local structure captured through IS analysis can be correlated with the MCT.
A simple method to measure the temperature and levitation height of devices rotating at cryogenic temperatures
Authors: de Bernardis Paolo , Columbro Fabio , Masi Silvia , Paiella Alessandro , Romeo Giovanni
Published: April 2020

We describe a simple system to measure the temperature and levitation height of levitating cryogenic devices in rotation. Devices of this kind are the half-wave-plates rotating on superconducting magnetic bearings used in several cryogenic polarimeters for the cosmic microwave background. The temperature measurement is important to monitor the radiative background and potential systematic effects in the polarimeter. In our implementation, the temperature sensor is a thermistor, physically mounted on the rotating device. The sensor is biased with an AC current, which is transferred from the stationary electronics to the rotating device via capacitive coupling. The levitation height sensor is a network of capacitors, similar to the one used for the capacitive coupling of the thermistor. We describe the optimization of the readout system and its performance, which has been tested on a room-temperature prototype. We show that this system reaches an accuracy better than 3% for the measurement of the thermistor resistance and an accuracy of ∼10 μm for the measurement of its levitation height.
Engineering the spin–orbit interaction in surface conducting diamond with a solid-state gate dielectric
Authors: Xing Kaijian , Tsai Alexander , Creedon Daniel L. , Yianni Steve A. , McCallum Jeffrey C. , Ley Lothar , Qi Dong-Chen , Pakes Christopher I.
Published: April 2020

Hydrogen-terminated (H-terminated) diamond, when surface transfer doped, can support a sub-surface two-dimensional (2D) hole band that possesses a strong Rashba-type spin–orbit interaction. By incorporating a V2O5/Al2O3 bilayer gate dielectric in a diamond-based metal–oxide–semiconductor architecture, metallic surface conductivity can be maintained at low temperature, avoiding the carrier freeze out exhibited by devices with an Al2O3 gate dielectric alone. Hole densities of up to 2.5 × 1013 cm−2 are achieved by the electrostatic gating of the device, and the spin–orbit interaction strength can be tuned from 3.5 ± 0.5 meV to 8.4 ± 0.5 meV, with a concurrent reduction in the spin coherence length from 40 ± 1 nm to 27 ± 1 nm. The demonstration of a gated device architecture on the H-terminated that avoids the need to cycle the temperature, as is required for ionic liquid gating protocols, opens a pathway to engineering practical devices for the study and application of spin transport in diamond.
Generation, electric detection, and orbital-angular momentum tunneling of twisted magnons
Authors: Chen Min , Schäffer Alexander F. , Berakdar Jamal , Jia Chenglong
Published: April 2020

A scheme for generating twisted magnons that carry orbital angular momentum in ferromagnetic nanodisks is presented. The topological signature of these eigenmode excitations entails particular features in the associated spin pumping currents. The latter is electrically detectable and can be used to identify these magnons. Considering two disks coupled via the dipole interaction, angular momentum tunneling is demonstrated. The predictions are based on a transparent analytical model and are confirmed by full numerical simulations. As the orbital angular momentum of the magnon is robust to damping, the current findings endorse the potential of twisted magnons for two-dimensional planar integrated spin-wave circuits.
Spatio-temporal coherence in vertically emitting GaAs-based electrically driven polariton lasers
Authors: Suchomel H. , Klaas M. , Betzold S. , Gagel P. , Beierlein J. , Klembt S. , Schneider C. , Höfling S.
Published: April 2020

We report on the implementation of a GaAs-based, vertically emitting electrically pumped polariton laser operated at cryogenic temperatures. The structure consists of a high quality factor AlGaAs/AlAs microcavity (Q=15 000) with two stacks of four GaAs quantum wells and features a Rabi splitting of 11 meV. Polariton lasing manifests by a clear threshold in the input–output characteristics of our device with a sharp drop in the emission linewidth and a continuous blueshift of 0.7 meV above threshold with increasing injection current. We measure spatial and temporal coherence of our device in the condensed phase by utilizing interference spectroscopy. Our results clearly demonstrate that electrically driven polariton lasers have promise as monolithic polaritonic sources of coherent light.
Scientific Writing = Thinking in Words
Authors: Lindsay David
Published: April 2020

Telling people about research is just as important as doing it. But many competent researchers are wary of scientific writing, despite its importance for sharpening scientific thinking, advancing their career, obtaining funding for their work and growing the prestige of their institution.
This second edition of David Lindsay’s popular book Scientific Writing = Thinking in Words presents a way of thinking about writing that builds on the way good scientists think about research. The simple principles in this book will help you to clarify the objectives of your work and present your results with impact. Fully updated throughout, with practical examples of good and bad writing, an expanded chapter on writing for non-scientists and a new chapter on writing grant applications, this book makes communicating research easier and encourages researchers to write confidently.
It is an ideal reference for researchers preparing journal articles, posters, conference presentations, reviews and popular articles; for students preparing theses; and for researchers whose first language is not English.
Reflections on the ‘Zimbabwean crisis 2000–2008’ and the survival strategies: the sustainable livelihoods framework (SLF) analysis
Authors: Kabonga Itai
Published: April 2020

In this paper, the author applies the Sustainable Livelihood Framework (SLF) to unravel the complexities inherent in the ‘Zimbabwean Crisis’. When unravelled from the SLF, the ‘Zimbabwean Crisis 2000-2008’ portrays a decimation of various forms of capital–financial, social, human, physical and natural–and forced Zimbabweans to innovate, show resourcefulness and ingenuity in generating various forms of capital to survive the scathing crisis. Broadly, thekukiya kiyastrategy has received little scholarly study and despite various survival strategies inherent in the kukiya kiya strategy. Thekukiya kiyalivelihood strategy prominence is seen in its adoption across the broad spectrum of society–educated, uneducated, employed, and unemployed, women, and men, young and old. The study ofkukiya kiyalivelihood strategy is important because it sustained thousands of households as the Zimbabwean formal sector collapsed. This reality is largely unappreciated in literature.
The role of urbanization of place of living in the relation between individual features and happiness (El papel del desarrollo urbanístico del lugar de residencia en la relación entre las características individuales y la felicidad)
Authors: Maricchiolo Fridanna , Mosca Oriana , Lauriola Marco , Krys Kuba
Published: April 2020

Happiness research tradition is focused on an independent form of happiness (Satisfaction with life, SWL), which in part neglects the social context and group well-being. We considered interdependent happiness (IH) to evaluate a collectivist conceptualization of happiness, which is based on harmony with others. We also considered the role of the perceived urbanization level of the place of living in the independent and interdependent happiness of people since in the literature there is no consensus about the impact of rural vs urban characterization of the living context on happiness. We hypothesized that place of living – rural vs urban – differently impacts on factors influencing independent or interdependent personal or familiar happiness. 290 university students of the Lazio Region in Italy participated to an online survey aimed to investigate the relation among self-construal, familism, personal and familiar independent and interdependent happiness. Results show that for people living in urban places, self-oriented individual factors concerned with self-realization, predicted satisfaction with life and interdependent happiness. For people living in rural places, other-oriented factors, more anchored to the group and community dimension, affected happiness for self and the family. Implications, limitations, and future directions are discussed.
Development of gateless quantum Hall checkerboard p–n junction devices
Authors: Patel Dinesh K , Marzano Martina , Liu Chieh-I , Kruskopf Mattias , Elmquist Randolph E , Liang Chi-Te , Rigosi Albert F
Published: April 2020

Measurements of fractional multiples of the

ν
=
2

plateau quantized Hall resistance (

R

H

≈ 12 906 Ω) were enabled by the utilization of multiple current terminals on millimetre-scale graphene p–n junction (pnJ) devices fabricated with interfaces along both lateral directions. These quantum Hall resistance checkerboard devices have been demonstrated to match quantized resistance outputs numerically calculated with the LTspice circuit simulator. From the devices’ functionality, more complex embodiments of the quantum Hall resistance checkerboard were simulated to highlight the parameter space within which these devices could operate. Moreover, these measurements suggest that the scalability of pnJ fabrication on millimetre or centimetre scales is feasible with regards to graphene device manufacturing by using the far more efficient process of standard ultraviolet lithography.
Model nuclear energy density functionals derived from ab initio calculations
Authors: Salvioni G , Dobaczewski J , Barbieri C , Carlsson G , Idini A , Pastore A
Published: April 2020

We present the first application of a new approach, proposed in (2016 J. Phys. G: Nucl. Part. Phys. 43 04LT01) to derive coupling constants of the Skyrme energy density functional (EDF) from ab initio Hamiltonian. By perturbing the ab initio Hamiltonian with several functional generators defining the Skyrme EDF, we create a set of metadata that is then used to constrain the coupling constants of the functional. We use statistical analysis to obtain such an ab initio-equivalent Skyrme EDF. We find that the resulting functional describes properties of atomic nuclei and infinite nuclear matter quite poorly. This may point to the necessity of building up the ab initio-equivalent functionals from more sophisticated generators. However, we also indicate that the current precision of the ab initio calculations may be insufficient for deriving meaningful nuclear EDFs.
Quantitative imaging of coronary flows using 3D ultrafast Doppler coronary angiography
Authors: Correia M , Maresca D , Goudot G , Villemain O , Bizé A , Sambin L , Tanter M , Ghaleh B , Pernot M
Published: April 2020

Coronary flow rate remains complex to assess in clinical practice using non-invasive, non-ionizing imaging tools. In this study, we introduce 3D ultrafast Doppler coronary angiography (3D UDCA), an ultrasound-based method to assess coronary blood flows in three-dimensions at high volume-rate and in one single heartbeat. We demonstrate that 3D UDCA can visualize the coronary vasculature with high temporal and spatial resolution and quantify the absolute flow. The feasibility of the technique was demonstrated in an open-chest swine model. The flow rate of the left-anterior descending artery (LAD) assessed by 3D UDCA was reconstructed successfully at the early diastolic and late diastolic phases and was in good agreement with an invasive gold-standard flowmeter during baseline, reactive hyperemia and coronary stenosis (r2 = 0.84). Finally, we demonstrate that a coronary stenosis on the LAD can be visualized as well as its associated flow acceleration.
Cellulose acetate-gelatin-coated boron-bioactive glass biocomposite scaffolds for bone tissue engineering
Authors: Moonesi Rad Reza , Alshemary Ammar Z , Evis Zafer , Keskin Dilek , Tezcaner Ayşen
Published: April 2020

In this study, we aimed to prepare and characterize porous scaffolds composed of pure and boron oxide (B2O3)-doped bioactive glass (BG) that were infiltrated by cellulose acetate-gelatin (CA-GE) polymer solution for bone tissue engineering applications. Composite scaffolds were cross-linked with glutaraldehyde after polymer coating to protect the structural integrity of the polymeric-coated scaffolds. The impact of B2O3 incorporation into BG-polymer porous scaffolds on the cross-sectional morphology, porosity, mechanical properties, degradation and bioactivity of the scaffolds was investigated. Human dental pulp stem cells (hDPSCs) were enzymatically isolated and used for cell culture studies. According to scanning electron microscope analysis, the porous structure of the scaffolds was preserved after polymer coating. After polymer infiltration, the porosity of the scaffolds decreased from 64.2% to 59.35% for pure BG scaffolds and from 67.3% to 58.9% for B2O3-doped scaffolds. Meanwhile, their compressive strengths increased from 0.13 to 0.57 MPa and from 0.20 to 0.82 MPa, respectively. After polymer infiltration, 7% B2O3-incorporated BG scaffolds had higher weight loss and Ca–P layer deposition than pure BG scaffolds, after 14 d of incubation in simulated body fluid at 37 °C. Higher attachment and proliferation of hDPSCs were observed on 7% B2O3-BG-CA/GE scaffolds. In addition, the alkaline phosphatase activity of the cells was about 1.25-fold higher in this group than that observed on BG-CA/GE scaffolds after 14 d of incubation in osteogenic medium, while their intracellular calcium amounts were 1.7-fold higher than observed on BG-CA/GE after 7 d of incubation in osteogenic medium. Our results suggested that porous cellulose acetate-gelatin-coated boron-BG scaffolds hold promise for bone tissue engineering applications.
Comparative study on structural, electronic, optical and mechanical properties of normal and high pressure phases titanium dioxide using DFT
Authors: Dharmale Neerja , Chaudhury Saurabh , Mahamune Rupesh , Dash Debashish
Published: April 2020

In this paper, a Self-consistent Orthogonalized linear combination of atomic orbitals (OLCAO) technique with a generalized gradient approximation such as Perdew–Burke–Ernzerhof Solid (GGA-PBE SOL) has been used to scrutinize the structural, optical, electronic and mechanical properties of normal pressure phase (Anatase and Rutile) and high pressure phase i.e., cubic (Fluorite and Pyrite) TiO2. Electronic and optical properties of normal pressure phases of TiO2 are also investigated using (Meta) MGGA-Tran and Blaha (TB09) and obtained results are a close approximation of experimental data. It is seen that the virtually synthesized structural parameter for cubic and tetragonal phases of TiO2 are consistent with experimental and theoretical data. From the effective mass of charge carriers (m*), it can be observed that pyrite TiO2 is having lower effective mass than the fluorite and hence shows higher photocatalytic activity than fluorite. Furthermore, it is seen that fluorite is more dense than anatase, rutile and pyrite TiO2. From the theoretical calculations on the optical properties, it can be concluded that optical absorption occursin the near UV region for high and normal pressue phases of TiO2. Again from the reflectivity characteristics R(ω), it can be concluded that TiO2 can be used as a coating material. Elastic constants, elastic compliance constants, mechanical properties are obtained for anatase, rutile, fluorite and pyrite TiO2. A comparison of the results with previously reported theoretical and experimental data shows that the calculated properties are in better agreement with the previously reported experimental and theoretical results.
Research for microstructure and mechanical properties of AZ91 magnesium alloy welded joint with magnetic field and activated flux
Authors: Guiqing Zhang , Yinglei Ren , Yunhai Su
Published: April 2020

Although many experimental researches have been carried out on the effect of different fluxes and the mechanism responsible for the higher penetration in activated TIG welding of magnesium alloy, few works as reported in literatures are available concering the grain refinement and the improvement of mechanical properties of welding joints. This is because the activated flux has very limited or even negative effects on improving the mechanical properties of welded joints. In order to find a method that can improve welding efficiency and mechanical properties of welded joints, the longitudinal alternating magnetic field and NiCl2 activated flux were used during TIG welding of AZ91 magnesium alloy. The formation, mechanical properties, phase composition and crystal growth pattern of the weld seam were tested and analyzed to study the mechanism. The experimental results reveal that with proper parameter matching (magnetic field and activated flux), larger weld penetration and smaller form factor can be obtained, welding efficiency is improved accordingly, but the form factor with the magnetic field is bigger than that without magnetic field. When the activated flux amount is 3 mg cm−2 with the magnetic field, the optimal value of mechanical properties of welded joint is obtained, tensile strength is 385 MPa, elongation is 13.3%, micohardness is 67 HV, respectively. All of these are better than those without the magnetic field, the optimal activated flux amount is 2 mg cm−2. The application of magnetic field and activated flux has no noticeable effect on the phase composition of weld seam. Under the combined action of magnetic field and activated flux, the crystallization nucleation condition of molten pool was changed, the grain size was refined, the formation of twins was promoted, and the crystals selectively grew within the basal (0001) plane.
Tailoring biomineralization and biodegradation of Mg–Ca alloy by acetic acid pickling
Authors: Rahim Shebeer A , Joseph M A , T Hanas
Published: April 2020

Magnesium and its alloys are suitable candidates for developing biodegradable metallic implants. However, the rapid degradation of these alloys in the physiological environment is a major limitation for such applications. In this work, Mg–Ca alloy was chemically treated with acetic acid and its effects on degradation behaviour were studied using simulated body fluid (SBF). The surface morphology and composition of the acid pickled samples were investigated using a scanning electron microscope (SEM) and infrared spectroscopy (IR). The degradation rate was analysed by conducting potentiodynamic polarization (PDP) and immersion tests. The results show that optimum acetic acid treatment improved the corrosion resistance by acid etching and formation of magnesium acetate layer. The treated samples also exhibited enhanced biomineralization and developed calcium phosphate layer on the surfaces during immersion tests. It is proposed that acetic acid pickling can be used as a reliable technique for surface modification as well as for pre-treatment of magnesium alloys to make them suitable for degradable metallic implant applications.
Effect of temperature gradient on microstructure and properties of GaSb crystals grown with Bridgman method
Authors: He Guofang , Gao Xiao , Han Yinfeng , Li Jikun , Liu Juncheng
Published: April 2020

GaSb crystal ingots were grown with vertical Bridgman method. The effects of temperature gradient on the structure and properties of GaSb crystals were investigated. When the temperature gradient increased from 5 to 7 °C cm−1, the crystallinity of the ingot improved, the dislocation density decreased by 55%, from 3928 to 1785 cm−2; the carrier mobility increased by 29.6%, from 868 to 1125 cm2 V−1 · s−1; the resistivity decreased 50.6%, from 12.45 to 6.332 × 10–3 Ω · cm; the infrared transmission increased from 27% to 32%. When the temperature gradient increased from to 7 to 9 °C cm−1, the crystallinity of the ingot deteriorated obviously, the dislocation density increased 4.38 times, from 3928 to 9609 cm−2; the carrier mobility decreased by 52.4%, from 1125 to 738 cm2 V−1 · s−1; the resistivity increased 6.2 times, from 6.332 to 23.94 × 10–3 Ω · cm; the infrared transmission decreased from 32% to 25%.
Magnetic vortex and unsaturated magnetization components in highly oriented pyrolytic graphite
Authors: Taallah Ayoub , Xia JiaChen , Guo Jian , Shuai Gao , Odunmbaku Omololu , Gong Min , Shang Hongyan , Corrias Anna , Boi Filippo S
Published: April 2020

Observation of ferromagnetic and granular superconductive features in highly-oriented-pyrolytic-graphite (HOPG) has recently attracted an important attention. We report a novel temperature dependent XRD and SQUID investigation of HOPG in the temperature range from 300.15 to 77.15 K. Unusual hysteresis features indicate the possible presence of vortex states in conditions of magnetic field approximately perpendicular to the HOPG layers. This interpretation is further supported by additional measurements performed on intermediate lamellae extracted by exfoliation. Evidence of a possible structural-transition in the c-axis of HOPG in the temperature range between 77 K and 100K is also provided by using the Rietveld refinement method. ZFC and FC measurements performed at high field values of 5000–10000 Oe, together with mFC-mZFC subtraction, highlight absence of a sharp depletion of the difference between magnetization signals towards zero. These observations may indicate the possible presence of additional unsaturated weak features, which are ascribed to superconductive signals as previously predicted by Scheike et al (Scheike et al 2013 Carbon; 59:140).
Witnessing entanglement in experiments with correlated noise
Authors: Dirkse Bas , Pompili Matteo , Hanson Ronald , Walter Michael , Wehner Stephanie
Published: April 2020

The purpose of an entanglement witness experiment is to certify the creation of an entangled state from a finite number of trials. The statistical confidence of such an experiment is typically expressed as the number of observed standard deviations of witness violations. This method implicitly assumes that the noise is well-behaved so that the central limit theorem applies. In this work, we propose two methods to analyze witness experiments where the states can be subject to arbitrarily correlated noise. Our first method is a rejection experiment, in which we certify the creation of entanglement by rejecting the hypothesis that the experiment can only produce separable states. We quantify the statistical confidence by a p-value, which can be interpreted as the likelihood that the observed data is consistent with the hypothesis that only separable states can be produced. Hence a small p-value implies large confidence in the witnessed entanglement. The method applies to general witness experiments and can also be used to witness genuine multipartite entanglement. Our second method is an estimation experiment, in which we estimate and construct confidence intervals for the average witness value. This confidence interval is statistically rigorous in the presence of correlated noise. The method applies to general estimation problems, including fidelity estimation. To account for systematic measurement and random setting generation errors, our model takes into account device imperfections and we show how this affects both methods of statistical analysis. Finally, we illustrate the use of our methods with detailed examples based on a simulation of NV centers.
Performance of bicontinuous structural electrolytes
Authors: Tu Vinh , Asp Leif E , Shirshova Natasha , Larsson Fredrik , Runesson Kenneth , Jänicke Ralf
Published: April 2020

Structural power composites are multifunctional materials with simultaneous load bearing and energy storing functionality. This is made possible due to carbon fibers’ ability to act not only as structural reinforcement materials, but also as electrode components. A crucial component of structural power composites is the structural electrolyte that is required to have both high stiffness and high ionic conductivity. To explore microstructure properties that bear optimal bifunctional performance a procedure is presented to generate various classes of synthetic microstructures with a wide span of properties for computer simulation. The effective properties of the generated artificial structural electrolytes are obtained via virtual material testing and compared with experimentally obtained data. Ultimately, a microstructure class with very good bifunctional properties is identified.
Complicated Alcohol Withdrawal—An Unintended Consequence of COVID-19 Lockdown
Authors: Narasimha Venkata Lakshmi , Shukla Lekhansh , Mukherjee Diptadhi , Menon Jayakrishnan , Huddar Sudheendra , Panda Udit Kumar , Mahadevan Jayant , Kandasamy Arun , Chand Prabhat K , Benegal Vivek , Murthy Pratima
Published: April 2020

Aim

To assess the impact of COVID-19-related lockdown in India on alcohol-dependent persons.

Method

We examined the change in the incidence of severe alcohol withdrawal syndrome presenting to hospitals in the city of Bangalore.

Results

A changepoint analysis of the time series data (between 01.01.20 to 11.04.20) showed an increase in the average number of cases from 4 to 8 per day (likelihood ratio test: χ2 = 72, df = 2, P < 0.001).

Conclusion

An unintended consequence of the lockdown was serious illness in some patients with alcohol use disorders.
Ecophysiology with barley eceriferum (cer) mutants: the effects of humidity and wax crystal structure on yield and vegetative parameters
Authors: von Wettstein-Knowles Penny
Published: April 2020

Background and Aims

In addition to preventing water loss, plant cuticles must also regulate nutrient loss via leaching. The eceriferum mutants in Hordeum vulgare (barley) potentially influence these functions by altering epicuticular wax structure and composition.

Methods

Cultivar ‘Bonus’ and five of its cer mutants were grown under optimal conditions for vegetative growth and maturation, and nine traits were measured. Nutrient and water amounts going through the soil and the amount of simulated rain as deionized water, affecting phyllosphere humidity, delivered during either the vegetative or maturation phase, were varied. Cer leaf genes and three wilty (wlt) mutations were characterized for reaction to toluidine blue and the rate of non-stomatal water loss.

Key Results

Vegetative phase rain on ‘Bonus’ significantly decreased kernel weight and numbers by 15–30 %, while in cer.j59 and .c36 decreases of up to 42 % occurred. Maturation phase findings corroborated those from the vegetative phase. Significant pleiotropic effects were identified: cer.j59 decreased culm and spike length and 1000-kernel weight, .c36 decreased kernel number and weight, .i16 decreased spike length and .e8 increased culm height. Excepting Cer.zv and .ym mutations, none of the other 27 Cer leaf genes or wlt mutations played significant roles, if any, in preventing water loss. Cer.zv and .ym mutants lost non-stomatal water 13.5 times faster than those of Cer.j, .yi, .ys and .zp and 18.3 times faster than those of four cultivars and the mutants tested here.

Conclusions

Using yield to measure the net effect of phyllosphere humidity and wax crystal structure revealed that the former is far more important than the latter. The amenable experimental setup described here can be used to delve deeper. Significant pleiotropic effects were identified for mutations in four Cer genes, of which one is known to participate in wax biosynthesis. Twenty-seven Cer leaf genes and three wlt mutations have little if any effect on water loss.
grünifai: interactive multiparameter optimization of molecules in a continuous vector space
Authors: Winter Robin , Retel Joren , Noé Frank , Clevert Djork-Arné , Steffen Andreas
Published: April 2020

Optimizing small molecules in a drug discovery project is a notoriously difficult task as multiple molecular properties have to be considered and balanced at the same time. In this work, we present our novel interactive in silico compound optimization platform termed grünifai to support the ideation of the next generation of compounds under the constraints of a multiparameter objective. grünifai integrates adjustable in silico models, a continuous representation of the chemical space, a scalable particle swarm optimization algorithm and the possibility to actively steer the compound optimization through providing feedback on generated intermediate structures.

Availability and implementation

Source code and documentation are freely available under an MIT license and are openly available on GitHub (https://github.com/jrwnter/gruenifai). The backend, including the optimization method and distribution on multiple GPU nodes is written in Python 3. The frontend is written in ReactJS.
HiC-Hiker: a probabilistic model to determine contig orientation in chromosome-length scaffolds with Hi-C
Authors: Nakabayashi Ryo , Morishita Shinichi
Published: April 2020

Motivation

De novo assembly of reference-quality genomes used to require enormously laborious tasks. In particular, it is extremely time-consuming to build genome markers for ordering assembled contigs along chromosomes; thus, they are only available for well-established model organisms. To resolve this issue, recent studies demonstrated that Hi-C could be a powerful and cost-effective means to output chromosome-length scaffolds for non-model species with no genome marker resources, because the Hi-C contact frequency between a pair of two loci can be a good estimator of their genomic distance, even if there is a large gap between them. Indeed, state-of-the-art methods such as 3D-DNA are now widely used for locating contigs in chromosomes. However, it remains challenging to reduce errors in contig orientation because shorter contigs have fewer contacts with their neighboring contigs. These orientation errors lower the accuracy of gene prediction, read alignment, and synteny block estimation in comparative genomics.

Results

To reduce these contig orientation errors, we propose a new algorithm, named HiC-Hiker, which has a firm grounding in probabilistic theory, rigorously models Hi-C contacts across contigs, and effectively infers the most probable orientations via the Viterbi algorithm. We compared HiC-Hiker and 3D-DNA using human and worm genome contigs generated from short reads, evaluated their performances, and observed a remarkable reduction in the contig orientation error rate from 4.3% (3D-DNA) to 1.7% (HiC-Hiker). Our algorithm can consider long-range information between distal contigs and precisely estimates Hi-C read contact probabilities among contigs, which may also be useful for determining the ordering of contigs.

Availability and implementation

HiC-Hiker is freely available at: https://github.com/ryought/hic_hiker.