bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimising zero-order suppression in ion-exchanged phase gratings
Authors: Montero-Orille Carlos , González-Núñez Héctor , Prieto-Blanco Xesús , Moreno Vicente , Mouriz Dolores , Nistal María C. , Liñares Jesús
Published: August 2020

Ion-exchange in glass is a well-known technique to fabricate phase optical elements. For elements with reduced dimensions, the side diffusion, intrinsic to ion-exchange processes, can affect the performance of these elements if it is not taken into account. Here we present a procedure to optimise the zero-order suppression of ion-exchanged phase gratings.
Scientific-technical investigations for development of optical multifunctional components for deflection, splitting and shaping of light beams
Authors: Henkel Sebastian , Barz Andrea , Bliedtner Jens , Kleinen Kurt
Published: August 2020

Many optical applications require splitting or deflection of light beams. This usually is achieved by usage of standard plane optical elements such as mirror systems or prismatic elements. However, these components are usually limited to one certain function and the manufacturing process for achieving precise functionality is very demanding. The presented research topic shows the development of new optical multifunctional components that introduce certain advantages compared to existing plane optical components. The basic roof-element configuration is based on glass cuboids joined together under a certain angle that can be fine adjusted during the manufacturing process. The components are therefore rather simply built and robust, and can fulfil different optical functions simultaneously by modifications of the glass cuboids. A process chain was developed for efficient and flexible manufacturing of such plane optical elements. Technical investigations were made on novel manufacturing processes such as ultrasonic assisted grinding and ultrafine grinding for fabrication of the cuboid parts, as well as diffusion joining being one possibility to create the basic roof-element shape.
Rotation-free industrial alignment of high performance optics
Authors: Leenman Dennis , Berndt Frederic , Beyer Stefan
Published: August 2020

Conventional production methods for high precision lens alignment typically rely on lens rotation. In the case of rotationally non-symmetric optics and mounts, this is problematic. Here, we report a new concept for alignment bonding without lens rotation, based on a high precision linear bearing as position reference and a hexapod actuator for lens manipulation. For the optical axis of two test lenses after bonding, <1 arcmin element tilt and <10 μm decentre was achieved. This is confirmed by an independent measurement. Our alignment device and process can be applied for any lens and mount geometry. This will be especially useful for high-end products with small size and for rotationally non-symmetric systems.
Polishing characteristics of sensitive glasses - experimental investigation
Authors: Vogt Christian , Rascher Rolf
Published: August 2020

Polishing is according to the current state of the art, one of the key processes in precision optics. Many specialists deal with the most diverse applications of these technologies and develop stable, reproducible techniques. In this article we present results for the investigation of different effects in the initial polishing phase in combination with different materials.
Polarization-sensitive optical coherence tomography as a tool to visualize the fiber direction of retinal nerves and peripapillary sclera
Authors: Willemse Joy , Verbraak Frank , de Boer Johannes
Published: August 2020

Polarization sensitive optical coherence tomography (PS-OCT) has been used to visualize the orientation of the nerves in the retinal nerve fiber layer (RNFL) and to visualize the orientation of the collagen fibers in peripapillary sclera in retinas of healthy volunteers. Optic axis orientation images clearly visualize the nerve fibers leaving the optic nerve head (ONH) in all radial directions. Sclera orientation images show that the sclera consist of two layers, an inner layer with an orientation parallel to the RNFL orientation, and a deeper layer where the collagen is circularly oriented.
Combined Brillouin and Raman system for biomedical applications
Authors: Rix Jan , Koch Edmund , Kirsch Matthias , Schackert Gabriele , Uckermann Ortrud , Galli Roberta
Published: August 2020

A VIPA based Brillouin spectrometer consisting of commercially available components has been combined with a standard Raman spectrometer and a confocal microscope allowing simultaneous and co-localized measurements of biological samples and tissues.
Strong light-matter coupling in dielectric metasurfaces
Authors: Castellanos Gabriel W. , Murai Shunsuke , Raziman T.V. , Wang Shaojun , Ramezani Mohammad , Curto Alberto G. , Gómez Rivas Jaime
Published: August 2020

We demonstrate the strong coupling between excitons in organic molecules and all-dielectric metasurfaces formed by arrays of silicon nanoparticles supporting Mie surface lattice resonances (MSLRs). Compared to Mie resonances in individual nanoparticles, MSLRs have extended mode volumes and much larger quality factors, which enables to achieve collective strong coupling with very large coupling strengths and Rabi energies. Moreover, due to the electric and magnetic character of the MSLR given by the Mie resonance, we show that the hybridization of the exciton with the MSLR results in exciton-polaritons that inherit this character as well. Our results demonstrate the potential of all-dielectric metasurfaces as novel platform to investigate and manipulate exciton-polaritons in low-loss polaritonic devices.
Quasi-normal mode expansion as a tool for the design of nanophotonic devices
Authors: Colom Rémi , Binkowski Felix , Betz Fridtjof , Hammerschmidt Martin , Zschiedrich Lin , Burger Sven
Published: August 2020

Many nanophotonic devices rely on the excitation of photonic resonances to enhance light-matter interaction. The understanding of the resonances is therefore of a key importance to facilitate the design of such devices. These resonances may be analyzed by use of the quasi-normal mode (QNM) theory. Here, we illustrate how QNM analysis may help study and design resonant nanophotonic devices. We will in particular use the QNM expansion of far-field quantities based on Riesz projection to design optical antennas.
Non-destructive testing of a rotating glass-fibre-reinforced polymer disc by swept source optical coherence tomography
Authors: Golde Jonas , Schnabel Christian , Filippatos Angelos , Wollmann Tino , Gude Maik , Koch Edmund
Published: August 2020

Composite materials are used for high-performance rotating blades, e.g. in turbines and wind power plants. Here, optical coherence tomography was used to visualize large areas of fibre-reinforcedpolymer discs at rotation speeds of up to 1200 rpm. These measurements allowed to visualize the fibre structure over large areas of the disc. By recording the front and back reflex, the wobble of the disc was measured precisely. Additionally, the recorded structure was used to detect even small deviations from a uniform rotation.
Absolute distance interferometry for subaperture stitching of large freeform optics
Authors: Spichtinger Jan , Schulz Michael , Ehret Gerd
Published: August 2020

We are developing a form measurement system for the surfaces of freeform optics and large conventional optics. The specifications of the optics are diameters up to 1.5 m and radii of curvature down to 10 m. This includes optics like telescope mirror segments and synchrotron optics. Using a Fizeau interferometer, we propose a subaperture stitching method that involves vertically aligning the interferometer’s optical axis to the local surface gradient and measuring the absolute distance from the interferometer’s reference flat to the specimen. Experimental results for the absolute distance measurement are shown.
Thinking Camera – Powered by the CAOS Camera Platform
Authors: Riza Nabeel A.
Published: August 2020

Introduced is the system level design of a Thinking Camera powered by the CAOS camera platform. The proposed camera provides features such as extreme linear dynamic range and full spectrum operations with selectable space-time-frequency CAOS pixel modes using active and passive light. The imager has triple output ports design and is controlled via application-specific classical image processing, machine learning techniques, and human/user feedback. Imaging capabilities cover multi-dimensional mappings allowing diverse full spectrum (350 nm to 2700 nm) applications from industrial metrology to quantitative medical imaging to artefact preserving colour photography.
White light intensity stabilization for long term photometric calibrations
Authors: Cachatra João , Alves David , Abreu Manuel
Published: August 2020

This paper presents an overview of the design of a voice coil based white light intensity stabilization tool. A system is created capable of mechanically stabilizing the fluctuations in a beam of light. This is achieved with a use of a voice coil and simple PID based feedback loop, controlled using a LabVIEW interface. Stability results are shown using Allan deviations curves.
Two wavelength frequency transfer over an optical fiber link
Authors: Pires Carlos , Abreu Manuel , Godinho Isabel , Agostinho Rui
Published: August 2020

In this paper we present the theory and the experimental setup used to transfer a standard frequency, to synchronize two clocks linked by an optical fiber. In order to verify the accuracy on frequency transfer over fiber link, we prepared an experiment that allows testing the performance of the setup for a variable set of environmental conditions, namely associated to temperature and vibration variations. The experimental setup shows the fiber optic link between one laboratory, where the standard frequency is generated, and another laboratory, where the equipment for simulating temperatures and vibrations are installed. The standard frequency, traceable to UTC(IPQ), is used to modulate two lasers with different wavelength,, injected in the optical fiber. At the end of the optical fiber the signals will be out of phase due to the inherent chromatic dispersion, which is also dependent on the temperature of the propagation media. Measuring the phase variations, caused by temperature gradients in the fiber, we can compensate the frequency transfer and synchronize the clocks. Evaluating all uncertainty components in this model, allows the metrological characterization of the synchronization and obtain the associated uncertainty of this quantity.
Membrane Environment Enables Ultrafast Isomerization of Amphiphilic Azobenzene -INVITED
Authors: Paternò G. M. , Colombo E. , Vurro V. , Lodola F. , Sesti V. , Benfenati F. , Bertarelli C. , Lanzani G.
Published: August 2020

We report on the isomerization dynamics of an amphiphilic azobenzene that dwells within the plasma membrane. We found that in aggregates formed in water, the isomerization reaction is hindered, while radiative deactivation is favoured. However, once in the membrane, the molecule reacquires its isomerisation capacity. These data fully account for the recently reported experiments in neurons, showing that the amphiphilic azobenzenes are effective light actuators for the modification of the electrical state of the membrane.
Evanescent Kerr effect using an optical nanofiber in acetone
Authors: Fanjoux Gil , Chrétien Jacques , Godet Adrien , Phan-Huy Kien , Beugnot Jean-Charles , Sylvestre Thibaut
Published: August 2020

We report on a theoretical and experimental investigation of the optical Kerr effect in the evanescent field of silica nanofibers immersed in several highly nonlinear liquids such as ethanol, acetone and water and we further compare them with air cladding. We provide formula of the effective nonlinear coefficients including the contribution of the nanofiber silica core and of the evanescent field for varying nanofiber diameter and for different surrounding media.
Long-time optical transmittance measurements of silica nanofibers
Authors: Bouhadida Maha , Lebrun Sylvie
Published: August 2020

We perform long-time measurements of the optical silica transmittance during several months in different environments and with different nanofiber lengths. These measurements are repeatable and give guidelines to control and to improve the lifetime and the performances of the nanofiber. The dust particles on the nanofiber surface is the fundamental reason behind its degradation. Enhancing the cleanness conditions of the nanofiber environment makes its lifetime increases significantly (from some hours to some months) and enables to avoid the dramatic decrease of its transmittance even after months. The nanofiber length does not contribute to the nanofiber transmittance degradation. Stabilizing the nanofiber transmittance after its decrease is possible by putting in in a dust free box.
Temperature wave-like oscillations on ultra-short and ultra-fast time scales -INVITED
Authors: Marco Gandolfi , Giulio Benetti , Christ Glorieux , Claudio Giannetti , Francesco Banfi
Published: August 2020

Recent findings in the frame of temperature wave-like oscillations on the ultra-short, ultra-fast time scales in solid states devices are here reviewed. The possibility for wave-like temperature oscillations are investigated at the light of the pass-band characteristic in w-k space for the temperature scalar field. The bandpass filter characteristics are accessed in terms of the heat carriers scattering times. The concepts here reviewed are of interest for perspective design of novel thermal nano-devices.
Nondestructive Characterization at Nanoscopic Scale by Photoacoustic and Photothermal Techniques -INVITED
Authors: Li Voti Roberto
Published: August 2020

Photoacoustic and Photothermal Spectroscopy are excellent techniques for studying the optical absorption spectra of opaque and highly light-scattering substances such as nanomaterials. In this paper we review recent advances in the methodology and its novel applications at the nanoscopic scale.
Autocompensating high-dimensional quantum cryptography by phase conjugation in optical fibers
Authors: Liñares-Beiras Jesús , Prieto-Blanco Xesús , Balado Daniel , Carral Gabriel M.
Published: August 2020

We present a system based on phase conjugation in optical fibers for autocompensating highdimensional quantum cryptohraphy. Phase changes and coupling effects are auto-compensated by a single loop between Alice and Bob. Bob uses a source of coherent states and next Alice attenuate them up to a single photon level and thus 1-qudit states are generated for implementing a particular QKD protocol, for instance the BB84 one, together with decoy states to detect eavesdropping attacks.
Nonlinear temporal Fresnel diffraction induced by phase jumps in fiber optics
Authors: Sheveleva Anastasiia , Finot Christophe
Published: August 2020

We numerically study the temporal patterns that emerge upon the propagation of one or two π phase jumps in a nonlinear optical fiber. Both normal and anomalous regimes of dispersion are considered. The analytical derivation of linear patterns based on Fresnel’s integrals provides some clues to better understand the properties of the resulting coherent structures.
Phase-coherent THz-wave demodulation with a photomixer
Authors: Constantin Florin Lucian
Published: August 2020

The nonlinear electrical response from a low temperature grown GaAs photomixer driven with the optical beat of two continuous-wave lasers allows frequency mixing between radiofrequency and THz-waves. Phase-sensitive demodulation of the signal from a modulated THz-wave is theoretically and experimentally demonstrated using a photomixer electrically driven with an alternative voltage at the modulation frequency.
An investigation of cutting parameters effect on sound level, surface roughness, and power consumption during machining of hardened AISI 4140
Authors: Şahinoğlu Abidin , Ulas Efehan
Published: August 2020

In recent years, the necessity for energy in the manufacturing industry has become an important problem because fossil fuel reserves are decreasing in order to produce energy. Therefore, the efficient use of energy has become an important research topic. In this study, energy efficiency is investigated in detail for sustainable life and manufacturing. AISI 4140 material with high hardness of 50 HRC hardness has been applied cryogenic process to improve mechanical and machinability properties. In this experiment study, the effects of feed rate (0.04, 0.08, 0.12 mm/rev), cutting speed (140, 160, 180 m/min), depth of cut (0.05, 0.10, 0.15 mm) and tool radius (0.4, 0.8) on energy consumption, surface roughness and sound intensity were investigated. Then, a new mathematical model with high accuracy was developed. Total power consumption was calculated by considering the instantaneous current value and machining time. As a result, it is found that good surface quality obtained when the feed rate is low, and the tool radius is high and the machining time is shortened, the energy consumption is reduced due to the increase in cutting speed, depth of cut and feed rate. Also, it is found that the tool radius has a limited effect on energy consumption, but low feed value increases energy consumption.
Three case reports on the cometary plasma tail in the historical documents
Authors: Hayakawa Hisashi , Fujii Yuri I. , Murata Koji , Mitsuma Yasuyuki , Cheng Yongchao , Nogami Nagatoshi , Ichikawa Kohei , Sano Hidetoshi , Tsumura Kohji , Kawamoto Yukiko , Nishino Masaki N.
Published: August 2020

Cometary tails visually manifest the solar wind and became an initial hint for its discovery. While the solar wind is being directly monitored with satellites, its time series before the space age has been controversially reconstructed with multiple proxies. Recently, archival reports of cometary plasma tails have been subjected to consideration to indirectly measure the solar wind but brought conclusion that no plasma tails had been reported prior to 1769 probably due to their brightness. However, historical records have occasionally reported comets with two tails even before 1769. These cases have been tentatively associated with visual reports of cometary plasma and dust tails. Therefore, we examined three such cases (C/1577 V1, 1P/837, and 1P/760), and compared the descriptions in historical records with calculated direction of their plasma tails. Our comparisons show that the records and calculations agree in these cases and plasma tails were visually recorded corresponding to these three great comets. These cases certify the capability of plasma tail observations with the unaided eye even before 1769, qualitatively imply their extreme brightness, proximities with the Sun and the Earth, relative enhancements of UV radiations, and interaction of cometary neutral atmosphere with solar wind plasma and magnetic field, while the lack of their detailed length or kink hinders us from their quantitative measuring. Further investigations will likely lead to the re-discovery of even more visual evidence of cometary plasma tails and, hence, improve our understanding on past space climate.
Leserbrief
Authors: Schuster Volker
Published: August 2020

Folgende Anmerkungen/Fragen schickte uns Herr Dr. Röhnelt als Leserbrief zum Impfheft der Zeitschrift Kinder- und Jugendmedizin, Ausgabe 2/2020:
Etablierung des Schwerpunktes Psoriasis an der Universitätshautklinik Rostock und eine praxisbezogene Übersicht über die Biologikatherapie der Psoriasis
Authors: Grünwald P. , Krebs S. , Troitzsch P. , Roewer J. , Emmert S. , Thiem A.
Published: August 2020

Die Diagnostik und Behandlung der Psoriasis stellt einen Schwerpunkt an der Universitätshautklinik Rostock dar. Aufgrund des breiten Spektrums verfügbarer Biologikatherapien für die Behandlung der Psoriasis werden in diesem Artikel praxisbezogene Ratschläge für diese Therapieform gegeben. Dabei wird aufgezeigt, wie das optimale Biologikum für einen individuellen Patienten unter Berücksichtigung möglicher Kontraindikationen, krankheitsspezifischer Aspekte und unerwünschter Wirkungen ausgewählt werden kann. Außerdem wird ein mögliches Vorgehen bei Unterbrechung, Wiederaufnahme oder Umstellung von Biologika erwähnt.
Synkopen
Authors: Gierthmühlen Janne , Baron Ralf
Published: August 2020

Die Synkope ist eine plötzlich eintretende, kurzzeitige Bewusstseinsstörung mit Tonusverlust, die ohne weitere Intervention vollständig reversibel ist. Eine Abgrenzung von anderen kurzzeitigen Veränderungen des Bewusstseins wie bei Epilepsien, Durchblutungsstörungen des Hirnstamms, metabolischen Störungen, Intoxikationen, psychogenen Anfällen und traumatischen Bewusstseinsstörungen ist wichtig, da sie die weitere Diagnostik leitet und die Therapie bedingt.
Einflussfaktoren für die Teilnahme an Sporttherapie in der psychiatrischen Versorgung
Authors: Friedrich Katrin , Krieger Julia , Rößner-Ruff Vanessa , Wendt Marcel , Ziegenbein Marc
Published: August 2020

Eine Vielzahl von Forschungsvorhaben weist auf die positive Wirkung von Sport und Bewegung bei der Behandlung von Menschen mit psychischen Erkrankungen hin. In der teil- und vollstationären psychiatrischen Versorgung werden in sporttherapeutischen Maßnahmen funktionelle, psychosoziale und pädagogische Ziele verfolgt. Die Studienlage deutet auf eine positive Wirkung von körperlicher Aktivität auf die psychische und physische Gesundheit hin. Neben Wirksamkeitsuntersuchungen fehlt es dennoch an praxisorientierten Fragestellungen, die sich mit der Umsetzung sporttherapeutischer Maßnahmen und deren Inanspruchnahme im klinischen Alltag befassen. Die vorliegende Studie untersucht mit qualitativen Methoden Einflussfaktoren für die Teilnahme an der Sporttherapie in einem psychiatrisch-psychosomatischen Fachkrankenhaus in Niedersachsen. Dabei wurden sowohl Mitarbeiter als auch Patienten in teil- und vollstationären Settings befragt. Es wurden intrapersonelle, organisatorische, interpersonelle und umweltbedingte Einflussfaktoren unterschieden, die für die Beteiligung an der Sporttherapie von Bedeutung sind. Die erarbeiteten Aspekte können Anhaltspunkte für die Praxis und für weitere Forschungsvorhaben bieten.
Internetbezogene Störungen bei Jugendlichen
Authors: Montag Christian , Wernicke Jennifer
Published: August 2020

Das Internet spielt im täglichen Leben von Jugendlichen eine entscheidende Rolle. Sie nutzen es, um mit Freunden zu kommunizieren, Musik, Bilder und Videos zu konsumieren oder Online-Spiele zu spielen. Das bringt allerdings die Gefahr mit sich, dass Jugendliche eine internetbezogene Störung (IBS; früher Internetsucht oder Internetabhängigkeit) entwickeln. Eine IBS wird mit verschiedenen negativen Konsequenzen in Zusammenhang gebracht, wie einem schlechteren psychischen Gesundheitszustand, Schlafstörungen, einem gestörten Essverhalten und schlechteren akademischen Leistungen. Die Risikofaktoren für die Entwicklung einer IBS sind dabei vielfältig und reichen von Depressivität, Ängstlichkeit und einer geringen Lebenszufriedenheit bis hin zu familiären Schwierigkeiten oder Problemen mit Gleichaltrigen. Allerdings gibt es protektive Schutzfaktoren, wie soziale Fähigkeiten, der eigene Selbstwert oder positive familiäre Beziehungen, die einer IBS entgegenwirken können.

Die vorliegende Übersichtsarbeit thematisiert den aktuellen Forschungsstand zur IBS, deren Risikofaktoren sowie präventive Maßnahmen, um der IBS bei Jugendlichen entgegenzuwirken.
Moderne Therapie der diabetischen sensomotorischen Polyneuropathie
Authors: Alin Stirban Ovidiu
Published: August 2020

Die Therapie der diabetischen sensomotorischen Polyneuropathie (DSPN) ist komplex und sollte auf die Behandlung von Defiziten und Symptomen sowie auf die Vermeidung von Komplikationen wie z. B. das diabetische Fußsyndrom zielen. Zu den wichtigsten Säulen der Therapie zählen eine optimale Stoffwechseleinstellung (vorrangig bei Typ-1-Diabetes) und eine neuroprotektive Lebensweise (vorrangig bei Typ-2-Diabetes) sowie eine pathogenetisch orientierte bzw. eine symptomatisch orientierte Therapie. Welche Therapie als Monotherapie oder Kombinationstherapie eingesetzt wird, hängt unter anderem vom individuellen klinischen Bild, den Komorbiditäten, der Verträglichkeit, aber auch den Präferenzen der Patienten ab. Dieser Beitrag erläutert die unterschiedlichen Therapien und schlägt einen möglichen Algorithmus vor.
Prolonged recovery of 3D printed, photo-cured polylactide shape memory polymer networks
Authors: Di Bartolo Alberto , Melchels Ferry P. W.
Published: August 2020

Shape memory polymers are materials that are able to retain a deformed state until an external stimulus, most typically heat, triggers recovery to the original geometry. Whereas typically, shape memory polymers are required to recover fast (seconds to minutes), many applications, particularly in the medical field, would benefit from a slow recovery (days to weeks). In this work, we exploit the broad glass transition range of photo-cured poly(D,L-lactide) dimethacrylate networks to obtain recovery times of up to 2 weeks, at 11 °C below the peak glass transition temperature of 58 °C. Recovery times decreased considerably for higher recovery temperatures, down to ∼10 min at 55 °C. A large spread in glass transition values (53.3–61.0 °C) was observed between samples, indicating poor reproducibility in sample preparation and, hence, in predicting shape recovery kinetics for individual samples. Furthermore, a staged recovery was observed with different parts of the samples recovering at different times. The ability to prepare complex structures using digital light processing stereolithography 3D printing from these polymers was confirmed. To the best of our knowledge, this work provides the first experimental evidence of prolonged recovery of shape memory polymers.
Comparative studies on ferroelectric switching kinetics of sputtered Hf0.5Zr0.5O2 thin films with variations in film thickness and crystallinity
Authors: Ryu Tae-Hyun , Min Dae-Hong , Yoon Sung-Min
Published: August 2020

Ferroelectric Hf0.5Zr0.5O2 (HZO) thin film capacitors with Pt/HZO/TiN structures were characterized to investigate the effects of oxygen partial pressure (PO2) and film thickness on the ferroelectric properties and switching dynamics of sputter-deposited HZO thin films. The PO2 during deposition and the film thickness varied from 0% to 1.5% and from 20 to 30 nm, respectively. The ferroelectric remnant polarization (2Pr) was 24.8 μC/cm2 for the 20-nm-thick HZO thin film deposited at a PO2 of 0% and decreased with increasing PO2 and film thickness due to variation in the amount of ferroelectric orthorhombic phase. The 2Pr of the 30-nm-thick HZO film deposited at a PO2 of 1% was 9.60 μC/cm2. The switching times and related parameters of the HZO films were estimated and analyzed by Kolmogorov–Avrami–Ishibashi and nucleation-limited switching (NLS) models. The NLS model provided better fitting results over the full range of polarization switching. The switching times could be modulated with variations in PO2 and film thickness from 0.46 to 1.58 μs. The activation field for polarization reversal increased with increasing PO2, and the degree of PO2 dependence was higher for a thinner film.
Machine learning Frenkel Hamiltonian parameters to accelerate simulations of exciton dynamics
Authors: Farahvash Ardavan , Lee Chee-Kong , Sun Qiming , Shi Liang , Willard Adam P.
Published: August 2020

In this manuscript, we develop multiple machine learning (ML) models to accelerate a scheme for parameterizing site-based models of exciton dynamics from all-atom configurations of condensed phase sexithiophene systems. This scheme encodes the details of a system’s specific molecular morphology in the correlated distributions of model parameters through the analysis of many single-molecule excited-state electronic-structure calculations. These calculations yield excitation energies for each molecule in the system and the network of pair-wise intermolecular electronic couplings. Here, we demonstrate that the excitation energies can be accurately predicted using a kernel ridge regression (KRR) model with Coulomb matrix featurization. We present two ML models for predicting intermolecular couplings. The first one utilizes a deep neural network and bi-molecular featurization to predict the coupling directly, which we find to perform poorly. The second one utilizes a KRR model to predict unimolecular transition densities, which can subsequently be analyzed to compute the coupling. We find that the latter approach performs excellently, indicating that an effective, generalizable strategy for predicting simple bimolecular properties is through the indirect application of ML to predict higher-order unimolecular properties. Such an approach necessitates a much smaller feature space and can incorporate the insight of well-established molecular physics.
Enhancement of fluorescence from nitrogen-vacancy center ensemble in bulk diamond with broadband antireflection coatings
Authors: Xu Lixia , Zhang Jixing , Bian Guodong , Fan Pengcheng , Li Mingxin , Liu Yuchen , Zhang Ning , Yuan Heng
Published: August 2020

The negatively charged nitrogen-vacancy (NV−) center in diamond is a promising platform for quantum sensing. However, fluorescence from the NV− centers suffers large energy loss at the diamond–air interface. Here, we propose a broadband antireflection coating to enhance the fluorescence intensity by simultaneously reducing the energy loss of the excitation laser and the fluorescence. The reflectance for normal-incidence light decreases from nearly 17% for bared diamond to below 0.33% for coated diamond in the wavelength range 500 nm–800 nm. The reflectance averaged over the fluorescence bandwidth is below 3% for angles of incidence less than 20°. The measured emitted fluorescence for the coated diamond is 1.44 times that of uncoated diamond, corresponding to nearly 20% improvement in the measurement sensitivity. The proposed method is significant for enhancing the signal-to-noise ratio of NV−-based sensors.
C2v and D3h symmetric InAs quantum dots on GaAs (001) substrate: Exciton emission and a defect field influence
Authors: Shang Xiangjun , Ma Ben , Ni Haiqiao , Chen Zesheng , Li Shulun , Chen Yao , He Xiaowu , Su Xingliang , Shi Yujun , Niu Zhichuan
Published: August 2020

InAs/GaAs quantum dots (QDs) grown on a GaAs (001) substrate were studied by photoluminescence spectroscopy. Both C2v and D3h QDs with featured XX11, X11+, and XX21+ spectra have been found. A local defect field tunes the dominant exciton from X+ to X or X−, enhances the population on XX, XXX, and XXX−, and induces tunneling and spectral diffusion. In D3h QDs, it also induces a prior e1–h2 transition and a structural polarization of XX21+ and XX11 to build a direct cascade XX21+ − X+. Both XX21+ − X+ and XX − X have no fine structure splitting, promising for entangled photon pair emission. A dominant X+ with slow electron capture (due to background holes) proves a pure single-photon emission.
The glass transition during liquid metal solidification exemplified by a Zr-based glass-forming alloy: Experiments and numerical simulations
Authors: Zhang Wei , Xiang Qingchun , Ma Chunyan , Ren Yinglei , Qiu Keqiang
Published: August 2020

By using Zr41.2Ti13.8Ni10Cu12.5Be22.5 (Vit1) bulk metallic glass with a defined cooling history, the heat capacity (Cp) of liquid and glass, and the calorimetric glass transition in differential scanning calorimetry experiments were investigated. Then, a thermal equilibrium model related to the melting and solidifying process was established to extrapolate the solidification glass transition (SGT) temperature range during liquid to glassy solid phase transformation. By using the extrapolated SGT temperature range, the thermodynamic parameters, including the Cp and thermal conductivity (λ), were adjusted, which can make the simulated cooling temperature curves accurately reflect the recorded ones. The coincidence of experimental and simulation results indicates the rationality of the thermal equilibrium model established in the present work. Furthermore, it is proposed that the SGT is resulted from the falling out-of-equilibrium of the undercooled liquid metal that acts as an endothermic trap to suppress the occurrence of recalescence.
Particle modeling of the spreading of coronavirus disease (COVID-19)
Authors: De-Leon Hilla , Pederiva Francesco
Published: August 2020

By the end of July 2020, the COVID-19 pandemic had infected more than 17 × 106 people and had spread to almost all countries worldwide. In response, many countries all over the world have used different methods to reduce the infection rate, such as case isolation, closure of schools and universities, banning public events, and forcing social distancing, including local and national lockdowns. In our work, we use a Monte Carlo based algorithm to predict the virus infection rate for different population densities using the most recent epidemic data. We test the spread of the coronavirus using three different lockdown models and eight various combinations of constraints, which allow us to examine the efficiency of each model and constraint. In this paper, we have tested three different time-cyclic patterns of no-restriction/lockdown patterns. This model’s main prediction is that a cyclic schedule of no-restrictions/lockdowns that contains at least ten days of lockdown for each time cycle can help control the virus infection. In particular, this model reduces the infection rate when accompanied by social distancing and complete isolation of symptomatic patients.
The effect of big-city news on rural America during the COVID-19 pandemic
Authors: Kim Eunji , Shepherd Michael E. , Clinton Joshua D.
Published: August 2020

Significance

The COVID-19 pandemic reminds us of the importance of local news for keeping the public informed about their community. However, because of how media markets are defined geographically, “local” television news is not equally local. For some rural residents, their local news often focuses on urban communities with issues quite different from their own. We show that rural residents are more likely to engage in social distancing behavior than otherwise similar rural residents if their local news is produced in a city that is more impacted by COVID-19. Despite the urban-rural differences, coverage of the pandemic’s impact in the more urban counties is able to slightly, but significantly, impact the willingness of rural residents to engage in social distancing.
Temporal and spatial variation in the environmental impacts of China’s resource extraction at the provincial scale
Authors: Wang He-Ming , Wei Yao , Zhao Shen , Liu Guang-Xin , Ma Fengmei , Wang Guo-Qiang , Wang Yao , Wang Xin-Zhe , Yang Dong , Liu Jing-Ru , Wang Hong-Tao , Shi Feng , Chen Wei-Qiang
Published: August 2020

Introduction:
Over the past two decades, China has experienced rapid economic development, which has not only led to a rapid increase in the use of raw materials but has also created environmental problems. This research analyzes the environmental impacts of resource extraction in China at the provincial level, and fully considers the environmental impact of various resources extraction. In addition, it is the first time to quantitatively study the spatial pattern and evolution characteristics of the environmental impacts of China’s resource extraction from multiple perspectives by means of spatial visualization.

Outcomes:
The results showed that the center of gravity of abiotic depletion potential (ADP) moved northwest, respiratory inorganics (RI) moved southwest and global warming potential (GWP) moved west. The results of the standard deviation ellipse showed that RI and GWP varied over time and space, while ADP showed a discrete trend. In addition, the distribution of the four in the northeast-southwest direction became more prominent.

Conclusion:
To mitigate the environmental impacts of resource extraction, we recommend that regional governments implement measures to control environmental impacts in the provinces within the distributed ellipse and design targeted policies based on actual conditions.
Affinity maturation is required for pathogenic monovalent IgG4 autoantibody development in myasthenia gravis
Authors: Fichtner Miriam L. , Vieni Casey , Redler Rachel L. , Kolich Ljuvica , Jiang Ruoyi , Takata Kazushiro , Stathopoulos Panos , Suarez Pablo A. , Nowak Richard J. , Burden Steven J. , Ekiert Damian C. , O’Connor Kevin C.
Published: August 2020

Pathogenic muscle-specific tyrosine kinase (MuSK)–specific IgG4 autoantibodies in autoimmune myasthenia gravis (MG) are functionally monovalent as a result of Fab-arm exchange. The development of these unique autoantibodies is not well understood. We examined MG patient–derived monoclonal autoantibodies (mAbs), their corresponding germline-encoded unmutated common ancestors (UCAs), and monovalent antigen-binding fragments (Fabs) to investigate how affinity maturation contributes to binding and immunopathology. Mature mAbs, UCA mAbs, and mature monovalent Fabs bound to MuSK and demonstrated pathogenic capacity. However, monovalent UCA Fabs bound to MuSK but did not have measurable pathogenic capacity. Affinity of the UCA Fabs for MuSK was 100-fold lower than the subnanomolar affinity of the mature Fabs. Crystal structures of two Fabs revealed how mutations acquired during affinity maturation may contribute to increased MuSK-binding affinity. These findings indicate that the autoantigen drives autoimmunity in MuSK MG through the accumulation of somatic mutations such that monovalent IgG4 Fab-arm–exchanged autoantibodies reach a high-affinity threshold required for pathogenic capacity.
How calcium helps α7 nicotinic acetylcholine receptors fulfill their potential
Authors: Short Ben
Published: August 2020

Study reveals that, at low acetylcholine concentrations, calcium enhances channel opening by binding to a novel motif near the ligand binding site.
Calibration of a compact absolute atomic gravimeter*
Authors: Xie Hong-Tai , Chen Bin , Long Jin-Bao , Xue Chun , Chen Luo-Kan , Chen Shuai
Published: August 2020

Compact atomic gravimeters are the potential next generation precision instruments for gravity survey from fundamental research to broad field applications. We report the calibration results of our home build compact absolute atomic gravimeter USTC-AG02 at Changping Campus, the National Institute of Metrology (NIM), China in January 2019. The sensitivity of the atomic gravimeter reaches

35.5

μ
Gal
/

Hz

(1 μGal = 1 × 10−8 m/s2) and its long-term stability reaches 0.8 μGal for averaging over 4000 seconds. Considering the statistical uncertainty, the dominant instrumental systematic errors and environmental effects are evaluated and corrected within a total uncertainty (2σ) of 15.3 μGal. After compared with the reference g value given by the corner cube gravimeter NIM-3A, the atomic gravimeter USTC-AG02 reaches the degree of equivalence of 3.7 μGal.
When to include ECoG electrode properties in volume conduction models
Authors: Vermaas M , Piastra M C , Oostendorp T F , Ramsey N F , Tiesinga P H E
Published: August 2020

Objective. Implantable electrodes, such as electrocorticography (ECoG) grids, are used to record brain activity in applications like brain computer interfaces. To improve the spatial sensitivity of ECoG grid recordings, electrode properties need to be better understood. Therefore, the goal of this study is to analyze the importance of including electrodes explicitly in volume conduction calculations. Approach. We investigated the influence of ECoG electrode properties on potentials in three geometries with three different electrode models. We performed our simulations with FEMfuns, a volume conduction modeling software toolbox based on the finite element method. Main results. The presence of the electrode alters the potential distribution by an amount that depends on its surface impedance, its distance from the source and the strength of the source. Our modeling results show that when ECoG electrodes are near the sources the potentials in the underlying tissue are more uniform than without electrodes. We show that the recorded potential can change up to a factor of 3, if no extended electrode model is used. In conclusion, when the distance between an electrode and the source is equal to or smaller than the size of the electrode, electrode effects cannot be disregarded. Furthermore, the potential distribution of the tissue under the electrode is affected up to depths equal to the radius of the electrode. Significance. This paper shows the importance of explicitly including electrode properties in volume conduction models for accurately interpreting ECoG measurements.
Developing a novel indicator to estimate years of life lost attributable to temperature variability between neighboring days
Authors: Chen Siqi , Hu Jianxiong , Gong Weiwei , Zhou Maigeng , Yu Min , Zhou Chunliang , Xiao Yize , Huang Biao , Xu Yanjun , Liu Tao , Xu Xiaojun , Lin Lifeng , Hu Ruying , Hou Zhulin , Li Junhua , Jin Donghui , Qin Mingfang , Zhao Qinglong , Yin Peng , Xu Yiqing , Xiao Jianpeng , Zeng Weilin , Li Xing , He Guanhao , Guo Lingchuan , Zhang Yonghui , Huang Cunrui , Ma Wenjun
Published: August 2020

The evidence is limited for the mortality burden of temperature variability between neighboring days. This study developed a novel indicator to measure temperature variability between neighboring days and quantify its mortality burden. Daily mortality and meteorological data during 2006–2017 from 364 locations across China were collected. We first employed a distributed lag non-linear model and multivariable meta-analysis to investigate the association between the diurnal temperature range (DTR) with the years of life lost (YLL) rate and the association between the nocturnal temperature range (NTR) with the YLL rate. Then, we calculated the weight temperature variability between neighboring days (weight-TVN) based on the attributable YLL rate of the DTR and NTR. The relationship between the weight-TVN and YLL rate was analyzed, and the attributable fraction (AF) of the YLL and weight-TVN related life loss per death was calculated to quantify the mortality burden. Stratified analyses were conducted by region, season, gender, age group and cause of death. The DTR-YLL rate curve and NTR-YLL rate curve were both J-shaped and a higher YLL rate attributable to DTR was observed than NTR. There was a significant association between the weight-TVN and YLL rate. An estimated AF of the weight-TVN was 6.02% (95%CI: 3.71%–8.33%). The average life loss per death due to weight-TVN was 0.93 year (95%CI: 0.57–1.29). Stratification analyses showed that the AFs of weight-TVN were relatively larger in southern China, in the cold season, in the elderly, females and patients with respiratory illnesses. Although the AF of weight-TVN among the young group (AF = 4.74%, 95%CI: 1.79%–7.69%) was lower than for the elderly (AF = 6.06%, 95%CI: 3.72%–8.41%), weight-TVN related life loss per death among the young population (1.51, 95%CI: 0.57–2.45) was much higher than in the elderly (0.59, 95%CI: 0.36–0.82). A novel indicator to measure temperature variability between neighboring days was developed, and temperature fluctuation between adjacent days significantly increased the mortality burden. Our results indicate that more attention should be paid to short-term temperature fluctuation.
Global offshore wind energy resources using the new ERA-5 reanalysis
Authors: Soares Pedro M M , Lima Daniela C A , Nogueira Miguel
Published: August 2020

A global quantitative characterization of offshore wind power density is presented over the economic exclusive zones (EEZs), at annual and seasonal scales, based on the recently released ECMWF ERA-5 reanalysis. Compared to its predecessors, ERA-5 features increased spatial and temporal resolutions, along with improved model parameterizations and data assimilation methodologies. Consequently, the present study represents an updated benchmark of wind resources over the global oceans. Further robustness to this argument is provided by our results showing that of the EEZs with large wind energy potential are characterized by regional-scale circulation features (coastal jets and breezes, land-sea and topographic circulations), known require high model resolution to be accurately simulated. Additionally, it is demonstrated that larger errors (up to 50%) can result from estimating wind power density from logarithmically extrapolated near-surface wind speed when compared to using high-resolution model level information. Coarser (daily) temporal resolution is also found to cause widespread increases in offshore wind power density errors between 10% and 30% compared to higher (hourly) resolution data. Further leveraging on the high vertical resolution of ERA-5, we show the large benefit of future increases in hub-heights from 100 m to 250 m for global offshore wind resources. Such technological advance results in widespread gains (ranging between +5% and +50%) throughout the global EEZs and no losses for all seasons. Moreover, the gains are >+10% for all regions with large wind energy potential at 100 m and >+40% over the Arctic Pacific sector and in regions characterized by the presence of coastal low-level jets.
Pulse laser thermography as a non-destructive method of latent surface defects of materials
Authors: Abramov Pavel I. , Kuznetsov Eugene V. , Lobanov Peter Y. , Sidoryuk Oleg E. , Skvortsov Leonid A.
Published: August 2020

The time dependences of the surface temperature increment of painted metal objects were studied depending on the thickness of the layer subjected to corrosion, as well as putty, restoring erosion defects on it. Hidden under a layer of paint, they cannot be detected remotely during normal visual observation. At the same time they are well detected by pulsed laser thermography. The experimental data in the work are compared with the results of mathematical modeling. Particular attention is paid to eliminating possible distortions caused by external contamination of the tested objects.
Development of the solar roof tile with internal cooling
Authors: Raz Karel , Chval Zdenek
Published: August 2020

This paper deals with the development of the roof tile with the integrated solar panel. This panel is cooled down with respect to maximizing of the efficiency. Dimensions of the tile are according generally used roof tile. Plastic solar tile can replace the regular one. The design of the tile was validated by usage of thermal simulations and flow simulations in NX Nastran software. These FEM solutions were validated by the measurement on the prototype. The output of this research is prototype from plastic material. This material was selected because of the fast and cheap production.
Fabrication of smart supramolecular systems based on polyelectrolytes and surfactants in microfluidic environment
Authors: Bezrukov Artem , Galyametdinov Yury
Published: August 2020

This work represents a process of fabrication of smart materials in a microfluidic confinement. Compared with macroscopic solutions, microfluidic convection-diffusion conditions create multiple additional factors that affect complexation in reacting polymer and surfactant flows. The system of convection-diffusion-reaction equations was solved to develop a polyelectrolyte-surfactant interaction model in a microchannel with laminar flows of reactants; phase formation and precipitation conditions in a microchannel were considered. The recommendations for control of phase behaviour in a microchannel were proposed by the design and operation mode of microfluidic devices used for synthesis of polymer-surfactant complexes and characterization of polymer-surfactant association process.