bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon network evolution from dimers to sheets in superconducting ytrrium dicarbide under pressure
Authors: Feng Xiaolei , Lu Siyu , Pickard Chris J. , Liu Hanyu , Redfern Simon A. T. , Ma Yanming
Published: November 2018

Carbon-bearing compounds display intriguing structural diversity, due to variations in hybrid bonding of carbon. Here, first-principles calculations and unbiased structure searches on yttrium dicarbide at pressure reveal four new structures with varying carbon polymerisation, in addition to the experimentally observed high-temperature low-pressure I4/mmm dimer phase. At low pressures, a metallic C2/m phase (four-member single-chain carbide) is stable, which transforms into a Pnma phase (single-chain carbide) upon increasing pressure, with further transformation to an Immm structure (double-chain carbide) at 54 GPa and then to a P6/mmm phase (sheet carbide) at 267 GPa. Yttrium dicarbide is structurally diverse, with carbon bonded as dimers (at lowest pressure), four-member single chains, infinite single chains, double chains and eventually sheet structures on compression. Electron–phonon coupling calculations indicate that the high-pressure phases are superconducting. Our results aid the understanding and design of new superconductors and illuminate pressure-induced carbon polymerisation in carbides.
On-cell catalysis by surface engineering of live cells with an artificial metalloenzyme
Authors: Szponarski Mathieu , Schwizer Fabian , Ward Thomas R. , Gademann Karl
Published: November 2018

Metal-catalyzed chemical transformations performed at the cellular level bear great potential for the manipulation of biological processes. The complexity of the cell renders the use of transition metal chemistry difficult in cellular systems. The delivery of the reactive catalyst and the control of its spatial localization remain challenging. Here we report the surface functionalization of the unicellular eukaryote Chlamydomonas reinhardtii with a tailor-made artificial metalloenzyme for on-cell catalysis. The functionalized cells remain viable and are able to uncage a fluorogenic substrate on their surface. This work leverages cell surface engineering to provide live cells with new-to-nature reactivity. In addition, this operationally simple approach is not genetically encoded and thereby transient, which offers advantages with regard to temporal control, cell viability, and safety. Therefore, and as a feature, the movement of the functionalized cells can be directed by light (via phototaxis), allowing for the three-dimensional localization of catalysts by outside stimuli.
Fluctuations in anthropogenic nighttime lights from satellite imagery for five cities in Niger and Nigeria
Authors: Bharti Nita , Tatem Andrew J.
Published: November 2018

Dynamic measures of human populations are critical for global health management but are often overlooked, largely because they are difficult to quantify. Measuring human population dynamics can be prohibitively expensive in under-resourced communities. Satellite imagery can provide measurements of human populations, past and present, to complement public health analyses and interventions. We used anthropogenic illumination from publicly accessible, serial satellite nighttime images as a quantifiable proxy for seasonal population variation in five urban areas in Niger and Nigeria. We identified population fluxes as the mechanistic driver of regional seasonal measles outbreaks. Our data showed 1) urban illumination fluctuated seasonally, 2) corresponding population fluctuations were sufficient to drive seasonal measles outbreaks, and 3) overlooking these fluctuations during vaccination activities resulted in below-target coverage levels, incapable of halting transmission of the virus. We designed immunization solutions capable of achieving above-target coverage of both resident and mobile populations. Here, we provide detailed data on brightness from 2000–2005 for 5 cities in Niger and Nigeria and detailed methodology for application to other populations.
Compositional effect of two-dimensional monodisperse AuPd bimetallic nanoparticle arrays fabricated by block copolymer nanopatterning on catalytic activity of CO oxidation
Authors: Kim Sun Mi , Mun Jeong Ho , Lee Si Woo , An Hyesung , Kim Hyun You , Kim Sang Ouk , Park Jeong Young
Published: November 2018

The activity increased with increasing Pd content and the resultant synergistic activity is can be precisely tuned by varying the chemical composition.
Tracking mitochondrial 1O2-ROS production through a differential mitochondria-nucleoli fluorescent probe
Authors: Flores-Cruz Ricardo , Jiménez-Sánchez Arturo
Published: November 2018

A dual-emissive fluorescent probe enabled unique tracking of 1O2-ROS species through a differential mitochondrial–nucleoli localization dynamic.
A dual signal amplification-assisted DNAzyme biosensor for ultrasensitive detection of Argonaute 2 activity
Authors: Zhang Dandan , Ma Fei , Leng Junhong , Zhang Chun-yang
Published: November 2018

We develop a new dual-signal amplification-assisted DNAzyme biosensor for sensitive detection of Argonaute 2 (Ago2) activity.
Rational molecular design: functional quinoline derivatives for PA detection, gaseous acid/base switching and anion-controlled fluorescence
Authors: Ma Yuqing , Zhang Yuyang , Kong Lin , Yang Jiaxiang
Published: November 2018

D-π-A quinoline derivatives were applied in PA detection, gaseous acid/base switching and anions-controlled fluorescence.
Electron-poor hemilabile dicationic palladium NHC complexes – synthesis, structure and catalytic activity
Authors: Schroeter Felix , Císařová Ivana , Soellner Johannes , Herdtweck Eberhardt , Strassner Thomas
Published: November 2018

Palladium complexes with an aryl-substituted hemilabile NHC ligand show a fluxional behavior and catalytic activity in the alkyne hydroarylation.
Fluxional motion in a dinuclear copper(i) complex with a propeller-type ligand: metal hopping on both sides
Authors: Kwon Hyunchul , Lee Eunsung
Published: November 2018

Fluxional motion of a dicopper(i) complex of hexa(2-pyridyl)benzene that accompanies metal hopping processes and ring rotation was studied.
The effect of 3d-electron configuration entropy on the temperature coefficient of redox potential in Co1−zMnz Prussian blue analogues
Authors: Iwaizumi Hiroki , Fujiwara Yusuke , Fukuzumi Yuya , Moritomo Yutaka
Published: November 2018

Recently, it was reported that a thermocell can convert temperature into electrical energy by using the difference in the thermal coefficient (α ≡ dV/dT) of the redox potential (V) between the cathode and anode materials.
High-yield paper-based quantitative blood separation system
Authors: Lu Zhengda , Rey Elizabeth , Vemulapati Sasank , Srinivasan Balaji , Mehta Saurabh , Erickson David
Published: November 2018

HYPER platform: affordable whole blood separation with unique cross-flow filtration that makes rapid diagnostics at point-of-care available.
Salt permeation mechanisms in charge-patterned mosaic membranes
Authors: Summe Mark J. , Sahoo Sushree Jagriti , Whitmer Jonathan K. , Phillip William A.
Published: November 2018

Charge-patterned mosaic membranes exhibit salt permeabilities that increase with decreasing concentration, which is opposite of the trend observed for single charge membranes.
Characterization of the metal status of natively purified alpha-synuclein from human blood, brain tissue, or recombinant sources using size exclusion ICP-MS reveals no significant binding of Cu, Fe or Zn
Authors: Lothian Amber , Lago Larissa , Mukherjee Soumya , Connor Andrea R. , Fowler Chris , McLean Catriona A. , Horne Malcolm , Masters Colin L. , Cappai Roberto , Roberts Blaine R.
Published: November 2018

The binding of Cu, Fe or Zn to alpha-synuclein has been implicated in neurodegenerative disease, such as Parkinson's.
Metal-free difunctionalization of alkynes leading to alkenyl dithiocyanates and alkenyl diselenocyanates at room temperature
Authors: Lu Ling-Hui , Zhou Si-Jia , He Wei-Bao , Xia Wen , Chen Ping , Yu Xianyong , Xu Xinhua , He Wei-Min
Published: November 2018

A facile and efficient protocol for the construction of alkenyl dithiocyanates and alkenyl diselenocyanates has been developed via stereoselective difunctionalization of alkynes with NaSCN or KSeCN at room temperature.
A new synthetic route to 5,6,11,12-tetraarylethynyltetracenes
Authors: Kitamura Kei , Asahina Kenta , Nagai Yusaku , Zhang Keshu , Nomura Shogo , Tanaka Katsunori , Hamura Toshiyuki
Published: November 2018

A new synthetic route to 5,6,11,12-tetrakis(arylethynyl)tetracenes, π-extended rubrenes, was developed via [4 + 2] cycloadditions of dialkynylisobenzofuran and 1,4-naphthoquinone.
Chiral isoxazolidine-mediated stereoselective umpolung α-phenylation of methyl ketones
Authors: Takeda Norihiko , Furuishi Mizuki , Nishijima Yuri , Futaki Erika , Ueda Masafumi , Shinada Tetsuro , Miyata Okiko
Published: November 2018

Asymmetric nucleophilic phenylation of N-alkoxyenamine with triphenylaluminium is achieved for the formation of enantioenriched α-phenyl ketones through a one-pot process.
Direct enantio- and diastereoselective Mannich reactions of isatin-derived ketimines with oxo-indanecarboxylates catalyzed by chiral thiourea derived from hydroquinidine
Authors: Liu Yuxin , Wang Jingdong , Wei Zhonglin , Cao Jungang , Liang Dapeng , Lin Yingjie , Duan Haifeng
Published: November 2018

A series of 3-substituted 3-amino-oxindoles were constructed by this protocol in excellent yields (92–99%) with high enantioselectivities (85–99% ee) and diastereoselectivities (up to >99 : 1 dr).
Heating-induced abnormal increase in Yb3+ excited state lifetime and its potential application in lifetime luminescence nanothermometry
Authors: Ji Zeliang , Cheng Yao , Cui Xiangshui , Lin Hang , Xu Ju , Wang Yuansheng
Published: November 2018

Heating-induced abnormal increase in Yb3+ excited state lifetime is demonstrated with potential application in lifetime luminescence nanothermometry.
Macro/microbehavior of shale rock under the dynamic impingement of a high-pressure supercritical carbon dioxide jet
Authors: Huang Fei , Hu Bin
Published: November 2018

This paper focuses on the damage of shale rock impacted by a high-pressure supercritical carbon dioxide (SC-CO2) jet.
Antenna array synthesis based on pre‐process coding neural network
Authors: Zhao Zhonghui , Zhao Huiling , Zheng Mingxuan
Published: November 2018

Antenna array synthesis based on the back propagation neural network is proposed in this Letter. The synthesis process is divided into three steps: pre‐processing, training, and post‐processing. In the pre‐processing, the interference directions and desired signal direction are coded so as to synthesise an arbitrary number of interferences. The back propagation neural network is unified to emulate the convex array synthesis model. To verify the performance of the network, the nine‐element and 11‐element linear array synthesis based on the neural network is realised and tested. Synthesis results show that the proposed method gives accurate approximation and have the good generalisation ability.
Adaptive shunt filtering control of UPQC for increased nonlinear loads
Authors: Choudhury Saurav Roy , Das Anubrata , Anand Sandeep , Tungare Sanjay , Sonawane Yogesh
Published: November 2018

In a distribution system, to compensate for the effect of voltage sag/swell and mitigate harmonic currents, a unified power quality conditioner (UPQC) is used. Conventionally, the power rating of UPQC is determined based on the expected sag/swell, linear and nonlinear loads. However, with the shift towards usage of electronic loads and electrical drives, the composition of nonlinear loads is increasing. Hence, the UPQC deployed earlier may not be capable of handling increased harmonic currents due to its limited current rating. While trying to compensate for both harmonic currents and voltage sag/swell, the shunt converter (of UPQC) may reach its current limit and would result in undesirable behaviour. To address this issue, a technique to prioritise sag/swell compensation over active filtering is proposed in this study. The remaining power capacity of UPQC (after sag/swell compensation) is utilised for harmonic filtering. Adaptive determination of harmonic compensation current also allows prioritising the various harmonics to be compensated. This helps in case passive tuned filters are installed for some harmonic frequencies for which UPQC need not respond. Detailed simulation studies are performed on MATLAB/SIMULINK platform and results are included in this study. A laboratory prototype of single phase UPQC is developed to validate the performance of the proposed scheme.
Comprehensive comparison of models for spectral energy distributions from 0.1μm to 1 mm of nearby star-forming galaxies
Authors: Hunt L. K. , De Looze I. , Boquien M. , Nikutta R. , Rossi A. , Bianchi S. , Dale D. A. , Granato G. L. , Kennicutt R. C. , Silva L. , Ciesla L. , Relaño M. , Viaene S. , Brandl B. , Calzetti D. , Croxall K. V. , Draine B. T. , Galametz M. , Gordon K. D. , Groves B. A. , Helou G. , Herrera-Camus R. , Hinz J. L. , Koda J. , Salim S. , Sandstrom K. M. , Smith J. D. , Wilson C. D. , Zibetti S.
Published: November 2018

We have fit the far-ultraviolet (FUV) to sub-millimeter (850μm) spectral energy distributions (SEDs) of the 61 galaxies from the Key Insights on Nearby Galaxies: A Far-Infrared Survey withHerschel(KINGFISH). The fitting has been performed using three models: the Code for Investigating GALaxy Evolution (CIGALE), the GRAphite-SILicate approach (GRASIL), and the Multiwavelength Analysis of Galaxy PHYSical properties (MAGPHYS). We have analyzed the results of the three codes in terms of the SED shapes, and by comparing the derived quantities with simple “recipes” for stellar mass (Mstar), star-formation rate (SFR), dust mass (Mdust), and monochromatic luminosities. Although the algorithms rely on different assumptions for star-formation history, dust attenuation and dust reprocessing, they all well approximate the observed SEDs and are in generally good agreement for the associated quantities. However, the three codes show very different behavior in the mid-infrared regime: in the 5–10μm region dominated by PAH emission, and also between 25 and 70μm where there are no observational constraints for the KINGFISH sample. We find that different algorithms give discordant SFR estimates for galaxies with low specific SFR, and that the standard recipes for calculating FUV absorption overestimate the extinction compared to the SED-fitting results. Results also suggest that assuming a “standard” constant stellar mass-to-light ratio overestimatesMstarrelative to the SED fitting, and we provide new SED-based formulations for estimatingMstarfrom WISE W1 (3.4μm) luminosities and colors. From a principal component analysis ofMstar, SFR,Mdust, and O/H, we reproduce previous scaling relations amongMstar, SFR, and O/H, and find thatMdustcan be predicted to within ∼0.3 dex using onlyMstarand SFR.
Das SAPHO-Syndrom – ein Überblick
Authors: Schreiber Judith , Kaufmann Bernd , Rauschmann Michael , de Groot Kirsten
Published: November 2018

Das SAPHO-Syndrom ist eine seltene entzündliche Autoimmunerkrankung mit Befall von Haut, Gelenken und Knochen.

Klassische Charakteristika der Erkrankung sind Gelenkentzündungen und Enthesitiden am axialen Skelett, an der ventralen Thoraxwand mit Enthesitis der Ligamenta costoclaviculares und Arthritiden der Sternocostalgelenke, Entzündungen von Wirbelkörpern und -gelenken, auch Bandscheiben und Iliosakralgelenken zusammen mit neutrophilen Dermatosen in Form von Acne conglobata, palmoplantarer Pustulose, Pyoderma gangraenosum u. a. Dazu können auch eine Osteitis und Osteomyelitis der Röhrenknochen (meist Femur oder Tibia) und Mono- oder Oligoarthritiden der unteren Extremitäten auftreten. Differenzialdiagnostisch sind Spondarthritiden und die chronisch rekurrierende multifokale Osteomyelitis nicht immer abzugrenzen.

Radiologisch sind nach längerem Krankheitsverlauf Hyperostosen an betroffenen Gelenken, Wirbelkörpern und Röhrenknochen nachweisbar. Wie auch bei HLA-B27-assoziierten Spondylarthritiden kann es zu ankylosierenden Veränderungen der Iliosakralgelenke oder Wirbelsäule kommen.

Für die Krankheitsentstehung spielen offenbar infektiöse Triggerfaktoren wie z. B. das Propionibacterium acnes eine Rolle, die zu einer überschießenden Immunantwort mit erhöhten Konzentrationen von IL-8, IL-18 und TNF-alpha i. S. führen. Die Entzündungen manifestieren sich dann in Form von sterilen Pseudoabszessen mit Infiltraten neutrophiler Granulozyten hauptsächlich im Bereich der Haut, am axialen Bewegungsapparat und z. T. an den unteren Extremitäten.

Zur Diagnostik können im Frühstadium (Krankheitsbeginn < 3 Monate) MRT, Skelettszintigrafie und Gelenksonografie eingesetzt werden. In späteren Stadien finden sich typische Hyperostosen und Sklerosierungen in konventionellen Röntgenaufnahmen.

Therapeutisch werden in erster Linie NSAR, bei längerfristig aktiven Arthritiden auch Colchicin oder klassische synthetische DMARDS wie Methotrexat, Sulfasalazin und Leflunomid eingesetzt. In der Behandlung der Osteitis sind gute Erfolge mit Bisphosphonaten erzielt worden. Des Weiteren haben sich TNF-alpha-Inhibitoren als längerfristig gut wirksam auf Haut- und Gelenkmanifestationen erwiesen.
Metabolische Azidose unter Paracetamol – eine ungewöhnliche Nebenwirkung
Authors: Hitzing Sandra , Böttcher Andrea , Laube Marcus
Published: November 2018

Die metabolische Azidose ist bei hospitalisierten Patienten keine Rarität. Doch nur selten ist eine metabolische Azidose mit erweiterter Anionenlücke unter chronischer Paracetamol-Therapie und konsekutiver transienter 5-Oxoprolin-Akkumulation (Pyroglutaminsäure) bei Erwachsenen beschrieben 1, 2, 3, 4. Dieser Beitrag stellt einen solchen Fall dar und erläutert die wenig bekannte Pathogenese.
Geburtshilfliche Anästhesie und postoperative Überwachung
Authors: Gude Philipp , Weber Thomas
Published: November 2018

Die von ASA (American Society of Anesthesiologists) und SOAP (Society for Obstetric Anesthesia and Perinatology) für das Jahr 2016 aktualisierten Leitlinien sind eine Handlungsempfehlung in erster Linie für Anästhesisten, die auf das anästhesiologische Management Gebärender, nicht operative und operative Entbindung sowie auf die postpartale Versorgung und Analgesie fokussiert.
Neuromonitoring und Therapieentscheidungen auf der Intensivstation
Authors: Reithmeier Thomas , Isaak Rimmon , Sanchez-Porres Renan
Published: November 2018

Bei Patienten mit einer akuten Hirnschädigung besteht das Risiko einer weiteren neurologischen Verschlechterung aufgrund der Entwicklung eines sekundären Hirnschadens. Ziel des Neuromonitorings ist es frühzeitig pathophysiologische Veränderung des Gehirns zu erkennen um adäquate diagnostische und therapeutische Maßnahmen einzuleiten, um die Entstehung eines sekundären Hirnschadens zu vermeiden. Neben der klassischen Methode des klinischen Neuromonitorings bei wachen Patienten werden invasive Methoden mit Implantation von Messsonden zur Bestimmung des Hirndruckes, des zerebralen Sauerstoffpartialdruckes sowie des Hirnmetabolismus bei komatösen Patienten angewendet. Ein elektrophysiologisches Monitoring mittels Elektrokortikografie oder evozierter Potenziale sowie die Messung des zerebralen Blutflusses liefert ergänzende Informationen. Die Indikationen und die klinische Relevanz der verschiedenen Monitoring-Techniken werden im Hinblick auf eine Optimierung der Behandlung von Patienten mit akuten zerebralen Schädigungen besprochen.
A high-order mode extended interaction oscillator operating in the Y band
Authors: Li Shuang , Wang Jianguo , Wang Dongyang , Xi Hongzhu , Teng Yan , Wang Bingbing , Wang Guangqiang
Published: November 2018

In this paper, we propose an extended interaction oscillator (EIO) operating with a high-order mode in the Y band. Compared to the conventional EIO operating with the fundamental mode, it operates with the TM31 mode. Since it operates with a high-order mode, the inner surface of the EIO is much larger, which increases the power capacity of the device. The difficulty in manufacturing such an enlarged cavity is thereby mitigated. By optimizing the multi-gap structure, designing the magnet subsystem, and preparing the e-gun subsystem, the configuration of EIO is confirmed. Finally, through particle-in-cell simulations, the performance of this device is studied. Under the conditions of 15 kV and 150 mA for the beam, the output power was around 85 W with a frequency of 338.4 GHz. The output signal was stable, showing the high reliability of this device.
30 GHz-voltage controlled oscillator operating at 4 K
Authors: Hollmann Arne , Jirovec Daniel , Kucharski Maciej , Kissinger Dietmar , Fischer Gunter , Schreiber Lars R.
Published: November 2018

Solid-state qubit manipulation and read-out fidelities are reaching fault-tolerance, but quantum error correction requires millions of physical qubits and therefore a scalable quantum computer architecture. To solve signal-line bandwidth and fan-out problems, microwave sources required for qubit manipulation might be embedded close to the qubit chip, typically operating at temperatures below 4 K. Here, we perform the first low temperature measurements of a 130 nm BiCMOS based SiGe voltage controlled oscillator at cryogenic temperature. We determined the frequency and output power dependence on temperature and magnetic field up to 5 T and measured the temperature influence on its noise performance. The device maintains its full functionality from 300 K to 4 K. The carrier frequency at 4 K increases by 3% with respect to the carrier frequency at 300 K, and the output power at 4 K increases by 10 dB relative to the output power at 300 K. The frequency tuning range of approximately 20% remains unchanged between 300 K and 4 K. In an in-plane magnetic field of 5 T, the carrier frequency shifts by only 0.02% compared to the frequency at zero magnetic field.
Laser-induced fluorescence measurements of acceleration zone scaling in the 12.5 kW HERMeS Hall thruster
Authors: Chaplin Vernon H. , Jorns Benjamin A. , Lopez Ortega Alejandro , Mikellides Ioannis G. , Conversano Ryan W. , Lobbia Robert B. , Hofer Richard R.
Published: November 2018

We present laser-induced fluorescence measurements of acceleration zone scaling with discharge voltage (Vd), magnetic field strength (B), and facility background pressure (PBG) in NASA’s 12.5 kW Hall Effect Rocket with Magnetic Shielding. At fixed discharge current, the plasma potential profiles at discharge voltages from 300 to 600 V approximately overlapped in the region with plasma potential less than 300 V; ion acceleration began further upstream at higher Vd because the region with a steep potential gradient was broader. The radial divergence of mean ion velocity vectors in the outer half of the channel and near plume increased with decreasing Vd. At fixed Vd, the acceleration zone was located further upstream at higher B and at higher PBG. Bimodal ion velocity distribution functions (IVDFs) were measured along the channel centerline in the acceleration zone at high discharge voltages; this effect was attributed to time-averaging over movement of the acceleration zone during large-amplitude discharge current oscillations. At lower discharge voltages, the broadening of the IVDFs in the near plume could not be fully explained by ionization within the acceleration region. These results have implications for understanding front pole erosion, which can be an important wear mechanism over the long lifetimes of magnetically shielded thrusters, and they provide baseline data for validating first principles models of cross-field electron transport.
Reduced scaling Hilbert space variational Monte Carlo
Authors: Wei Haochuan , Neuscamman Eric
Published: November 2018

We show that for both single-Slater-Jastrow and Jastrow geminal power wave functions the formal cost scaling of Hilbert space variational Monte Carlo can be reduced from fifth to fourth order in the system size, thus bringing it in line with the long-standing scaling of its real space counterpart. While traditional quantum chemistry methods can reduce costs related to the two-electron integral tensor through various tensor decomposition methods, we show that such approaches are ineffective in the presence of Hilbert space Jastrow factors. Instead, we develop a simple semi-stochastic approach that can take similar advantage of the near-sparsity of this four-index tensor. Through demonstrations on alkanes of increasing length, we show that accuracy and overall statistical uncertainty are not meaningfully affected and that a total cost crossover is reached as early as 50 electrons when using a minimal basis. Further study will be needed to assess where the crossover occurs in more compact molecular geometries and larger basis sets and to explore how in that context the crossover can be accelerated.
Wavelength-selective thermal extraction for higher efficiency and power density thermophotovoltaics
Authors: Jurado Zoila , Kou Junlong , Kamali Seyedeh Mahsa , Faraon Andrei , Minnich Austin J.
Published: November 2018

Thermophotovoltaics have long been of interest as an energy conversion technology but suffer from low power density and low efficiency. Structured emitters designed to alter the emission spectrum and increase the efficiency are not stable at the necessary high emitter temperatures and also reduce the power density. Here, we propose a wavelength-selective thermal extraction device that mitigates these challenges and demonstrate a transfer-printing process needed to fabricate the device. The device consists of a ZnS solid hemisphere with a patterned thin film optical filter that passively increases the far-field radiated flux from an emitter within a wavelength band near the bandgap of a photovoltaic cell. Crucially, the device does not need to be in physical contact with the emitter and thus can be maintained at a lower temperature, circumventing the thermal stability challenge. Our work helps one to address long-standing issues with applications of thermophotovoltaics.
Asynchronous optical sampling data-acquisition trigger-signal derived from pulse coherence coincidence
Authors: Zhang Hongfei , Su Bo , Yang Xue , Wu Yaxiong , He Jingsuo , Zhang Cunlin , Jones David R.
Published: November 2018

We propose a data acquisition trigger signal, suitable for free-space, asynchronous optical sampling (ASOPS) systems, based on Laser Pulse Coherence (LPC). At 1 GHz laser pulse repetition frequencies and higher, this method becomes an attractive alternative to established techniques, as it lacks the necessity of high peak pulse intensity, maximising the total laser power available for measurements. Additional advantages are the large unamplified signal generated, ease of initial alignment, and greatly reduced beam pointing stability errors. Employing a LPC trigger source, we realise a sub 30 fs trigger timing error for our ASOPS system.
Transient carrier transport and rearrangement of Schottky barrier layers under the action of a bias applied to the M/PZT/M structure
Authors: Delimova L. A. , Yuferev V. S.
Published: November 2018

A drift-diffusion model of unsteady carrier transport in an M/lead zirconate titanate (PZT)/M structure is proposed. It is assumed that the PZT film has electronic conductivity. Electrons are generated by oxygen vacancies and trapped by Ti+3 deep centers. It is assumed that electrons move in the electric field by hopping between titanium atoms, with an effective mobility that is considered constant. To account for the polarization, it is believed that, near the contacts, there are thin defective layers in which the polarization is zero, while outside these layers, the polarization does not vary across the film thickness and depends on the applied bias. The model was used to account for the formation of the current peak in the current–voltage curves, which is not caused by the domain switching and observed in epitaxial films only when the bias and polarization directions coincide. It is shown that a pronounced current peak is formed when (а) an accumulated space-charge layer appears near one of the contacts under the action of polarization and (b) this contact is cathode, which is only possible when the polarization and bias directions coincide. As a result, electrons flow between space-charge layers, and the film resistance first decreases and then starts to increase again, and this gives rise to a current peak. It is shown that this effect is purely nonstationary. The model also made it possible to estimate the basic parameters of the structure: electron mobility, density of oxygen vacancies, dielectric constant, defect layer thickness, and barrier height.
Order of chemical reaction and convective boundary condition effects on micropolar fluid flow over a stretching sheet
Authors: Matta Anjanna , Gajjela Nagaraju
Published: November 2018

The study of chemical reaction and convective boundary conditions on thermosolutal behavior of magneto hydrodynamic (MHD) fluid flow above a stretching sheet has been investigated in the current investigation. A mathematical model is established and the governing partial differential system is modified into a set of nonlinear coupled ordinary differential system and it is evaluated by using the numerical scheme of RK method. The physical importance of different flow variables such as the magnetic parameter, vortex viscosity parameter, order of chemical reaction, Prandtl, skin friction coefficient and Eckert numbers are discussed in detailed through graphical representation.
Thermal characterization of gallium oxide Schottky barrier diodes
Authors: Chatterjee Bikramjit , Jayawardena Asanka , Heller Eric , Snyder David W. , Dhar Sarit , Choi Sukwon
Published: November 2018

The higher critical electric field of β-gallium oxide (Ga2O3) gives promise to the development of next generation power electronic devices with improved size, weight, power, and efficiency over current state-of-the-art wide bandgap devices based on 4H-silicon carbide (SiC) and gallium nitride (GaN). However, it is expected that Ga2O3 devices will encounter serious thermal issues due to the poor thermal conductivity of the material. In this work, self-heating in Ga2O3 Schottky barrier diodes under different regimes of the diode operation was investigated using diverse optical thermography techniques including thermoreflectance thermal imaging, micro-Raman thermography, and infrared thermal microscopy. 3D coupled electro-thermal modeling was used to validate experimental results and to understand the mechanism of heat generation for the diode structures. Measured top-side and cross-sectional temperature fields suggest that device and circuit engineers should account for the concentrated heat generation that occurs near the anode/Ga2O3 interface and/or the lightly doped drift layer under both forward and high voltage reverse bias conditions. Results of this study suggest that electro-thermal co-design techniques and top-side thermal management solutions are necessary to exploit the full potential of the Ga2O3 material system.
Influence of Hall current and wall conductivity on hydromagnetic mixed convective flow in a rotating Darcian channel
Authors: Singh J. K. , Begum S. G. , Seth G. S.
Published: November 2018

In the present study, an analysis for steady hydromagnetic mixed convective generalised Couette flow between two infinite parallel plates of arbitrary electrical conductivities and finite thicknesses filled with a porous medium in the presence of a uniform transverse magnetic field in a rotating system with the Hall effect is presented. The heat transfer characteristics of the fluid flows are also investigated, taking viscous and Joule dissipations into account. Exact solutions of the resulting simultaneous ordinary differential equations governing the fluid flows are obtained in a closed form. The closed form analytical solutions for shear stress and mass flow rate are also obtained. To examine the physical consequences and flow characteristics, the numerical results for velocity, induced magnetic field, temperature field, shear stress, mass flow rate, and rate of heat transfer are computed for different values of various system parameters and are displayed in graphical and tabular forms. An interesting observation recorded that there arises flow reversal in the secondary flow direction when the permeability parameter is very small, i.e., when Darcian drag force is very large.
Massive stabilization of gravity-driven film flows with corrugated side walls
Authors: Kögel Armin , Aksel Nuri
Published: November 2018

In this paper, we study the stabilizing effect of corrugated side walls on gravity-driven film flows over a flat substrate in an open channel. For this purpose, we use both flat side walls and corrugated side walls with attached sharp tips to measure both the steady state flow and the primary instability. Furthermore, we vary the channel width as well as the stream wise distance between the tips. We report on two different stabilizing effects: (1) A stabilization against free surface perturbations due to the reduction of the channel width that appears for flat side walls as well as for corrugated side walls. (2) A distinct maximum in the stabilization for corrugated side walls when varying the tip distance. A stabilization up to five times the value for the classical two dimensional Nusselt flow was possible. All measurements are consistent with the limiting cases. For the limit of very broad channels, the effect of the side walls vanishes. For the limits of very small and very large tip distances, the side walls correspond to flat side walls. Finally, we bring together the basic flow with the measured shifts in the instability. To our knowledge, this is the first work which reports the effect of corrugated side walls on gravity-driven film flows. Since stable, uniform thin films are of major interest for many technical applications and side walls are often unavoidable, we expand the knowledge of film flows with side walls and present a method to significantly improve their stability.
The oblique firehose instability in a bi-kappa magnetized plasma
Authors: Meneses A. R. , Gaelzer R. , Ziebell L. F.
Published: November 2018

In this work, we derive a dispersion equation that describes the excitation of the oblique (or Alfvén) firehose instability in a plasma that contains both electron and ion species modelled by bi-kappa velocity distribution functions. The equation is obtained with the assumptions of low-frequency waves and moderate to large values of the parallel (respective to the ambient magnetic field) plasma beta parameter, but it is valid for any direction of propagation and for any value of the particle gyroradius (or Larmor radius). Considering values for the physical parameters typical to those found in the solar wind, some solutions of the dispersion equation, corresponding to the unstable mode, are presented. In order to implement the dispersion solver, several new mathematical properties of the special functions occurring in a kappa plasma are derived and included. The results presented here suggest that the superthermal characteristic of the distribution functions leads to reductions to both the maximum growth rate of the instability and of the spectral range of its occurrence.
Microfluidic generation of self-contained multicomponent microcapsules for self-healing materials
Authors: Zhang Chengbin , Gao Wei , Zhao Yuanjin , Chen Yongping
Published: November 2018

Bioinspired self-healing carriers can cost-effectively repair crack damage in functional materials without detection, analysis, or any type of human intervention. In this study, an effective structured self-healing microcarrier is prepared through a single-step microfluidic method. These microcarriers are self-contained core-shell microcapsules with the healant and the curing agent encapsulated in separate chambers of a single capsule. Because microfluidics are versatile, our fabrication method generates unique structures in which the ratio of the agents can be precisely adjusted, and thus, the reaction kinetics and the cost can be well controlled. Such carriers can be embedded into various material matrices, including bulk pellets and film materials, which maintain satisfactory mechanical properties after being damaged and repaired. These attractive features may establish an approach for microfluidic preparation of self-healing materials and may open up avenues for the development of intelligent self-healing materials for military equipment, electronic products, architectural materials, etc.
Working memory capacity and strategy use in second language learning
Authors: Najjari Rahim , Mohammadi Mohammad
Published: November 2018

This study investigated the relationship between working memory capacity (WMC) and second language learning strategies. To this
end, 151 participants took three working memory tasks: one simple span task and two complex span tasks. They then completed the
Strategy Inventory for Language Learning (SILL). Finally, they were put into three groups of individuals with high, mid, and low
WMC. The results of descriptive and inferential statistics (one-way ANOVA tests) revealed that individuals with high WMC
reportedly used compensatory and cognitive strategies more than the other two groups. Then, two-way factorial designs of WMC with
the variables of age, sex, and language proficiency were conducted on reported frequency of compensatory and cognitive strategy
use. The findings demonstrated that the main and interaction effects of the variables were not statistically significant except
for WMC. This study has implications for language learning strategies and working memory studies in second language learning
settings.
Endothelial cells act as gatekeepers for LTβR-dependent thymocyte emigration
Authors: James Kieran D. , Cosway Emilie J. , Lucas Beth , White Andrea J. , Parnell Sonia M. , Carvalho-Gaspar Manuela , Tumanov Alexei V. , Anderson Graham , Jenkinson William E.
Published: November 2018

The emigration of mature thymocytes from the thymus is critical for establishing peripheral T cell compartments. However, the pathways controlling this process and the timing of egress in relation to postselection developmental stages are poorly defined. Here, we reexamine thymocyte egress and test current and opposing models in relation to the requirement for LTβR, a regulator of thymic microenvironments and thymocyte emigration. Using cell-specific gene targeting, we show that the requirement for LTβR in thymocyte egress is distinct from its control of thymic epithelium and instead maps to expression by endothelial cells. By separating emigration into sequential phases of perivascular space (PVS) entry and transendothelial migration, we reveal a developmentally ordered program of egress where LTβR operates to rate limit access to the PVS. Collectively, we show the process of thymic emigration ensures only the most mature thymocytes leave the thymus and demonstrate a role for LTβR in the initiation of thymus emigration that segregates from its control of medulla organization.
The hERG potassium channel intrinsic ligand regulates N- and C-terminal interactions and channel closure
Authors: Codding Sara J. , Trudeau Matthew C.
Published: November 2018

Human ether-à-go-go–related gene (hERG, KCNH2) voltage-activated potassium channels are critical for cardiac excitability. hERG channels have characteristic slow closing (deactivation), which is auto-regulated by a direct interaction between the N-terminal Per-Arnt-Sim (PAS) domain and the C-terminal cyclic nucleotide binding homology domain (CNBHD). hERG channels are not activated by the binding of extrinsic cyclic nucleotide ligands, but rather bind an “intrinsic ligand” that is composed of residues 860–862 within the CNBHD and mimics a cyclic nucleotide. The intrinsic ligand is located at the PAS–CNBHD interface, but its mechanism of action in hERG is not well understood. Here we use whole-cell patch-clamp electrophysiology and FRET spectroscopy to examine how the intrinsic ligand regulates gating. To carry out this work, we coexpress PAS (a PAS domain fused to cyan fluorescent protein) in trans with hERG “core” channels (channels with a deletion of the PAS domain fused to citrine fluorescent protein). The PAS domain in trans with hERG core channels has slow (regulated) deactivation, like that of WT hERG channels, as well as robust FRET, which indicates there is a direct functional and structural interaction of the PAS domain with the channel core. In contrast, PAS in trans with hERG F860A core channels has intermediate deactivation and intermediate FRET, indicating perturbation of the PAS domain interaction with the CNBHD. Furthermore, PAS in trans with hERG L862A core channels, or PAS in trans with hERG F860G,L862G core channels, has fast (nonregulated) deactivation and no measurable FRET, indicating abolition of the PAS and CNBHD interaction. These results indicate that the intrinsic ligand is necessary for the functional and structural interaction between the PAS domain and the CNBHD, which regulates the characteristic slow deactivation gating in hERG channels.
Status competition in Africa: Explaining the Rwandan–Ugandan clashes in the Democratic Republic of Congo
Authors: Tamm Henning
Published: November 2018

Yoweri Museveni’s rebels seized power in Uganda in 1986, with Rwandan refugees making up roughly a quarter of his troops. These refugees then took power in Rwanda in 1994 with support from Museveni’s regime. Subsequently, between 1999 and 2000, the Rwandan and Ugandan comrades-in-arms turned on each other in a series of deadly clashes in the Democratic Republic of Congo, a country they had invaded together only one year earlier. What explains these fratricidal clashes? This article contends that a social–psychological perspective focused on status competition between the Rwandan and Ugandan ruling elites provides the most compelling answer. Long treated as ‘boys’, the new Rwandan rulers strove to enhance their social status vis-à-vis the Ugandans, seeking first equality and then regional superiority. Economic disputes over Congo’s natural resources at times complemented this struggle for status but cannot explain all of its phases. The article draws on interviews with senior Rwandan, Ugandan, and former Congolese rebel officials, and triangulates them with statements given to national and regional newspapers at the time of the clashes. More broadly, it builds on the recently revitalized study of status competition in world politics and makes a case for integrating research on inter-African relations.
A.R. Luria’s Approach to Neuropsychological Assessment and Rehabilitation
Authors: Mikadze Yuri V , Ardila Alfredo , Akhutina Tatiana V
Published: November 2018

Luria is one of the most influential authors in cognitive neuroscience, and in particular neuropsychology. New scientific achievements and clinical observations have significantly supported many of his suggestions and hypotheses. The article describes the basic concepts of neuropsychological evaluation and rehabilitation, associated with the method of syndrome analysis developed by Luria for diagnosis mental function and focus in the qualitative interpretation of the results neuropsychological diagnosis. Luria is regarded as a pioneer in cognitive rehabilitation. His ideas have maintained relevance and have continued to be developed and analyzed. Luria is presented as one of the major founders of contemporary neuropsychology from the fundamental point of view and the clinical perspective. His influence has continued significantly during the 21st century.
A 5-microRNA signature identified from serum microRNA profiling predicts survival in patients with advanced stage non-small cell lung cancer
Authors: Zhang Yajie , Roth Jack A , Yu Hao , Ye Yuanqing , Xie Kunlin , Zhao Hua , Chang David W , Huang Maosheng , Li Hecheng , Qu Jieming , Wu Xifeng
Published: November 2018

Circulating microRNAs (miRNAs) are potential biomarkers for cancer diagnosis, screening and prognosis. This study aimed to identify serum miRNAs as predictors of survival in patients with advanced non-small cell lung cancer (NSCLC). We profiled serum miRNAs in a pilot set of four patients with good survival (>24 months) and four patients with poor survival (<6 months). We selected 140 stably detectable miRNAs and 42 miRNAs reported in literature for further analysis. Expression of these 182 miRNAs was measured using high-throughput polymerase chain reaction assay, and their association with 3-year survival in the discovery (n = 345) and validation (n = 177) cohorts was assessed. Five serum miRNAs (miR-191, miR-28-3p, miR-145, miR-328 and miR-18a) were significantly associated with 3-year overall survival in both cohorts. A combined 5-miRNA risk score was created to assess the cumulative impact of these miRNAs on risk of death. Quartile analysis of the risk score showed significant association with 3-year death risk, with a 4.6-, 6.8- and 9.3-month reduction in median survival time for the second, third and fourth quartiles, respectively. Survival tree analysis also identified distinct risk groups with different 3-year survival durations. Data from The Cancer Genome Atlas revealed all five miRNAs were differentially expressed (P < 0.0001) in paired tumor and normal tissues. Pathway analysis indicated that target genes of these five miRNAs were mainly enriched in inflammatory/immune response pathways and pathways implicated in resistance to chemoradiotherapy and/or targeted therapy. Our results suggested that the 5-miRNA signature could serve as a prognostic predictor in patients with advanced NSCLC.
Invasive fungal infections in the immunocompromised host: Mechanistic insights in an era of changing immunotherapeutics
Authors: Eades Christopher P , Armstrong-James Darius P H
Published: November 2018

The use of cytotoxic chemotherapy in the treatment of malignant and inflammatory disorders is beset by considerable adverse effects related to nonspecific cytotoxicity. Accordingly, a mechanistic approach to therapeutics has evolved in recent times with small molecular inhibitors of intracellular signaling pathways involved in disease pathogenesis being developed for clinical use, some with unparalleled efficacy and tolerability. Nevertheless, there are emerging concerns regarding an association with certain small molecular inhibitors and opportunistic infections, including invasive fungal diseases. This is perhaps unsurprising, given that the molecular targets of such agents play fundamental and multifaceted roles in orchestrating innate and adaptive immune responses. Nevertheless, some small molecular inhibitors appear to possess intrinsic antifungal activity and may therefore represent novel therapeutic options in future. This is particularly important given that antifungal resistance is a significant, emerging concern. This paper is a comprehensive review of the state-of-the-art in the molecular immunology to fungal pathogens as applied to existing and emerging small molecular inhibitors.