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Jan 2019 • Energies

Design optimization of a permanent-magnet saturated-core fault-current limiter

John Linden, Yasha Nikulshin, Alex Friedman, Yosef Yeshurun, Shuki Wolfus

Designs of saturated-cores fault current limiters (FCLs) usually implement conducting or superconducting DC coils serving to saturate the magnetic cores during nominal grid performance. The use of coils adds significantly to the operational cost of the system, consuming energy, and requiring maintenance. A derivative of the saturated-cores FCL is a design implementing permanent magnets as an alternative to the DC coils, eliminating practically all maintenance due to its entirely passive components. There are, however, various challenges such as the need to reach deep saturation with the currently available permanent magnets as well as the complications involved in the assembly process due to very powerful magnetic forces between the magnets and the cores. This paper presents several concepts, achieved by extensive magnetic simulations and verified experimentally, that help in maximizing the core saturation of the PMFCL (Permanent Magnet FCL), including optimization of the permanent magnet to core surface ratios and asymmetrical placement of the permanent magnets, both creating an increase in the cores’ magnetic flux at crucial points. In addition, we point to the importance of splitting the AC coils to leave the center core point exposed to best utilize their variable inductance parameters. This paper also describes the stages of design and assembly of a laboratory-scale single phase prototype model with the proposed PMFCL design recommendations, as well as an analysis of real-time results obtained while connecting this prototype to a 220 V grid during nominal and fault states. View Full-Text

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Jan 2019 • Cell reports

A chaperone lid ensures efficient and privileged client transfer during tail-anchored protein targeting

Un Seng Chio, SangYoon Chung, Shimon Weiss, Shu-ou Shan

Molecular chaperones play key roles in maintaining cellular proteostasis. In addition to preventing client aggregation, chaperones often relay substrates within a network while preventing off-pathway chaperones from accessing the substrate. Here we show that a conserved lid motif lining the substrate-binding groove of the Get3 ATPase enables these important functions during the targeted delivery of tail-anchored membrane proteins (TAs) to the endoplasmic reticulum. The lid prevents promiscuous TA handoff to off-pathway chaperones, and more importantly, it cooperates with the Get4/5 scaffolding complex to enable rapid and privileged TA transfer from the upstream co-chaperone Sgt2 to Get3. These findings provide a molecular mechanism by which chaperones maintain the pathway specificity of client proteins in the crowded cytosolic environment.

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Jan 2019 • Polyhedron

Preparation and characterization of bis (guanidinium) and bis (aminotetrazolium) dodecahydroborate salts: Green high energy nitrogen and boron rich compounds

Pessia Sharon, Michal Afri, Sergey Mitlin, Levi Gottlieb, Bruria Schmerling, Dan Grinstein, Shmuel Welner, Aryeh A Frimer

This paper describes the syntheses, crystallization, characterization and energetic properties (calorimetry) of closo-dodecahydroborate salts with guanidinium and aminotetrazolium based cations. The salts were readily produced in good yields by metathesis (ion exchange) reactions depending on the water solubility of the dodecahydroborate salts. Water insoluble salts can be synthesized from the potassium or sodium salts by a simple metathesis reaction with the corresponding halide of the desired organic cation. Water soluble salts can be prepared via two consecutive metathesis reactions: the halide is first converted to the corresponding sulfate, which is reacted in turn with barium dodecahydroborate, yielding the water soluble organic closo(B12H12)2− salt and the insoluble BaSO4. The product salt is conveniently isolated by water evaporation. The aminotetrazolium salt 12d gives nice crystals when …

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Jan 2019 • Graefe's Archive for Clinical and Experimental Ophthalmology

Antibacterial and physical properties of a novel sonochemical-assisted Zn-CuO contact lens nanocoating

Yoav Nahum, Reut Israeli, Gabriel Mircus, Ilana Perelshtein, Miriam Ehrenberg, Shay Gutfreund, Aharon Gedanken, Irit Bahar

PurposeThis work examined the antibacterial and physical effects of a novel Zn-CuO nanocoating applied on a silicone hydrogel contact lens.MethodsZn-CuO coating of PureVision balafilcon-A soft contact lenses (Bausch&Lomb, Rochester, NY) was performed by sonochemical deposition using a high-intensity ultrasonic horn. Non-coated PureVision lenses served as a control in all experiments. Adhesion assays for P. aerueginosa and S. epidermidis to the coated lenses were performed to identify the minimal coating concentration which still possessed antibacterial activity. Lens water content, oxygen transfer light transfer, leaching, and electron microscopy studies were performed using this concentration.ResultsCoated lenses showed 3–5 log reductions in adhesion of both species. The lowest tested coating …

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Jan 2019 • Physical review letters

Evidence for collective nonlinear interactions in X ray into ultraviolet parametric down-conversion

D Borodin, A Schori, J-P Rueff, JM Ablett, S Shwartz

Jan 2019 • The Journal of Physical Chemistry C

Surface Phases and Surface Freezing in an Ionic Liquid

Diego Pontoni, Julia Haddad, Bridget M Murphy, Sven Festersen, Oleg Konovalov, Benjamin M Ocko, Moshe Deutsch

Room temperature ionic liquids (RTILs), a novel class of liquid salts, are intensively studied for their basic science and numerous emerging applications. When undercooled, RTILs comprising long alkyl chains often exhibit liquid crystal (LC) bulk phases. However, only one molecular-resolution experimental structure study was published for their LC surface phases. We measured the temperature evolution of another LC surface phase, using surface specific Å-resolution X-ray methods. This phase’s existence range, 90 °C, much exceeds the corresponding bulk phase’s 3 °C. Its thickness, L, confirms the theory-predicted logarithmic temperature dependence, with an amplitude equaling the bulk correlation length. Surprisingly, at L’s divergence temperature, a ∼20 Å thick, hexagonally packed, crystalline monolayer forms at, and fully covers, the sample’s surface. It is identified as a surface-frozen Langmuir–Gibbs film …

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Jan 2019 • Quantum Electronics

Coherent elastographic tomography via speckle time multiplexing

A Schwarz, N Ozana, R Califa, A Shemer, H Genish, Z Zalevsky

A method is suggested for separating photons coming from different depths of tissue while externally stimulating tissue via infra-sonic vibration. The process of tomographic information extraction using the speckle time multiplexing approach is presented. Use is also made of a modulated laser combining a speckle-pattern tracking method for sensing surface tilting changes with an interferometer for sensing surface z-axis changes at the same scan time.

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Jan 2019 • Batteries & Supercaps

Cover Picture: The Electrochemical Sodiation of FeSb2: New Insights from Operando 57Fe Synchrotron Mössbauer and X‐Ray Absorption Spectroscopy (Batteries …

Marcus Fehse, Dimitrios Bessas, Ali Darwiche, Abdelfattah Mahmoud, Guy Rahamim, Camille La Fontaine, Raphael P Hermann, David Zitoun, Laure Monconduit, Lorenzo Stievano, Moulay T Sougrati

The Front Cover shows how synchrotron radiation is important to study battery materials for many different applications. In this work, operando synchrotron-based characterisation techniques, specifically X-ray absorption and Mössbauer spectroscopy, were applied to elucidate the FeSb 2 charge–discharge mechanism. More information can be found in the article by M. Fehse et al.(DOI: 10.1002/batt. 201800075).

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Jan 2019 • Communications biology

A high-throughput integrated microfluidics method enables tyrosine autophosphorylation discovery

Hadas Nevenzal, Meirav Noach-Hirsh, Or Skornik-Bustan, Lev Brio, Efrat Barbiro-Michaely, Yair Glick, Dorit Avrahami, Roxane Lahmi, Amit Tzur, Doron Gerber

Autophosphorylation of receptor and non-receptor tyrosine kinases is a common molecular switch with broad implications for pathogeneses and therapy of cancer and other human diseases. Technologies for large-scale discovery and analysis of autophosphorylation are limited by the inherent difficulty to distinguish between phosphorylation and autophosphorylation in vivo and by the complexity associated with functional assays of receptors kinases in vitro. Here, we report a method for the direct detection and analysis of tyrosine autophosphorylation using integrated microfluidics and freshly synthesized protein arrays. We demonstrate the efficacy of our platform in detecting autophosphorylation activity of soluble and transmembrane tyrosine kinases, and the dependency of in vitro autophosphorylation assays on membranes. Our method, Integrated Microfluidics for Autophosphorylation Discovery (IMAD), is high …

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Jan 2019 • The Journal of Physical Chemistry C

Controlling chemical selectivity in electrocatalysis with chiral CuO-coated electrodes

KB Ghosh, Wenyan Zhang, F Tassinari, Y Mastai, O Lidor-Shalev, R Naaman, P Möllers, D Nürenberg, H Zacharias, J Wei, E Wierzbinski, DH Waldeck

This work demonstrates the chiral-induced spin selectivity effect for inorganic copper oxide films and exploits it to enhance the chemical selectivity in electrocatalytic water splitting. Chiral CuO films are electrodeposited on a polycrystalline Au substrate, and their spin filtering effect on electrons is demonstrated using Mott polarimetry analysis of photoelectrons. CuO is known to act as an electrocatalyst for the oxygen evolution reaction; however, it also generates side products such as H2O2. We show that chiral CuO is selective for O2; H2O2 generation is strongly suppressed on chiral CuO but is present with achiral CuO. The selectivity is rationalized in terms of the electron spin-filtering properties of the chiral CuO and the spin constraints for the generation of triplet oxygen. These findings represent an important step toward the development of all-inorganic chiral materials for electron spin filtering and the creation of …

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Jan 2019 • Batteries & Supercaps

The Electrochemical Sodiation of FeSb2: New Insights from Operando 57Fe Synchrotron Mössbauer and X‐Ray Absorption Spectroscopy

Marcus Fehse, Dimitrios Bessas, Ali Darwiche, Abdelfattah Mahmoud, Guy Rahamim, Camille La Fontaine, Raphael P Hermann, David Zitoun, Laure Monconduit, Lorenzo Stievano, Moulay T Sougrati

Operando Sb K‐edge X‐ray absorption spectroscopy and 57Fe Synchrotron Mössbauer Spectroscopy, used for the first time in the field of operando energy storage materials, assisted by operando magnetic measurements, were combined to clarify the role of iron and antimony in the electrochemical reaction mechanism of FeSb2 as negative electrode material for sodium‐ion batteries (SIB). Both datasets were analyzed using an innovative chemometric approach involving principal component analysis (PCA) and multivariate curve resolution – alternating least square analysis (MCR‐ALS) yielding new insights on the sodiation reaction. Our findings show that the reaction of Na with FeSb2 during discharge leads to the formation of Na3Sb along with superparamagnetic Fe amorphous nanoparticles which contain small amounts of Sb dissolved in their lattice. During the following desodiation, the pristine material …

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Jan 2019 • The Electrochemical Society Interface

Electrolyte solutions for “beyond Li-ion batteries”: Li-S, Li-O2, and Mg batteries

Daniel Sharon, Michael Salama, Ran Attias, Doron Aurbach

This article describes electrolyte solutions aspects of three battery systems considered as" beyond Li-ion batteries." The common denominator of these systems is the importance of the nature of the electrolyte solutions, which determines their reversibility. Li-S batteries are very close to practical importance, offering the highest energy density among rechargeable batteries. Li-oxygen systems are theoretically most promising, but the poor compatibility of most polar-aprotic solvents with the oxygen reduction species is a major obstacle for practical development. Developing rechargeable Mg batteries also involves a challenge in the choice of electrolyte solutions compatible with both reversible Mg anodes and high potential/high capacity Mg ions insertion cathodes.

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Jan 2019 • BioRxiv

Grass silica mineralizer (GSM1) protein precipitates silica in sorghum silica cells

Santosh Kumar, Nurit Adiram-Filiba, Shula Blum, Javier Arturo Sanchez-Lopez, Oren Tzfadia, Ayelet Omid, Hanne Volpin, Yael Heifetz, Gil Goobes, Rivka Elbaum

• Silicon is absorbed by plant roots as silicic acid. In shoot tissues, silicic acid 27 mineralizes as silica by completely unknown mechanisms. Most prominently, leaf 28 epidermal cells called silica cells deposit silica in most of their volume. 29• Using bioinformatics tools, we identified a previously uncharacterized protein in 30 sorghum (Sorghum bicolor), which we named as Grass Silica Mineralizer (GSM1). 31 We characterized the expression profile and demonstrated its activity in vitro and in 32 vivo. 33• GSM1 is a basic protein with seven repeat units rich in proline, lysine and glutamic 34 acid. We found GSM1 expression in immature leaf and inflorescence tissues. In the 35 active silicification zone of sorghum leaf, GSM1 was localized to the cytoplasm or 36 near cell boundaries of silica cells. GSM1 was packed in vesicles and secreted to the 37 paramural space. A short peptide, repeating five times in the protein precipitated silica 38 in vitro at a biologically relevant silicic acid concentration. Raman and NMR 39 spectroscopies showed that the peptide attached the silica through lysine amine 40 groups, forming a mineral-peptide open structure. Transient overexpression of GSM1 41 in sorghum resulted in ectopic silica deposition in all leaf epidermal cell types. 42• Our results show that GSM1 precipitates silica in sorghum silica cells. 43

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Jan 2019 • Nature

Loss of ADAR1 in tumours overcomes resistance to immune checkpoint blockade

Jeffrey J Ishizuka, Robert T Manguso, Collins K Cheruiyot, Kevin Bi, Arpit Panda, Arvin Iracheta-Vellve, Brian C Miller, Peter P Du, Kathleen B Yates, Juan Dubrot, Ilana Buchumenski, Dawn E Comstock, Flavian D Brown, Austin Ayer, Ian C Kohnle, Hans W Pope, Margaret D Zimmer, Debattama R Sen, Sarah K Lane-Reticker, Emily J Robitschek, Gabriel K Griffin, Natalie B Collins, Adrienne H Long, John G Doench, David Kozono, Erez Y Levanon, W Nicholas Haining

Most patients with cancer either do not respond to immune checkpoint blockade or develop resistance to it, often because of acquired mutations that impair antigen presentation. Here we show that loss of function of the RNA-editing enzyme ADAR1 in tumour cells profoundly sensitizes tumours to immunotherapy and overcomes resistance to checkpoint blockade. In the absence of ADAR1, A-to-I editing of interferon-inducible RNA species is reduced, leading to double-stranded RNA ligand sensing by PKR and MDA5; this results in growth inhibition and tumour inflammation, respectively. Loss of ADAR1 overcomes resistance to PD-1 checkpoint blockade caused by inactivation of antigen presentation by tumour cells. Thus, effective anti-tumour immunity is constrained by inhibitory checkpoints such as ADAR1 that limit the sensing of innate ligands. The induction of sufficient inflammation in tumours that are sensitized …

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Jan 2019 • Infrared Physics & Technology

The opportunity of using InGaAsN/AlGaAs quantum wells for extended short-wavelength infrared photodetection

Asaf Albo, Dan Fekete, Gad Bahir

We propose and demonstrate a novel concept to address high-performance, extended short wavelength (e-SWIR) photodetectors. Our approach is based on shifting the well-developed GaAs quantum-well infrared photodetector (QWIP) technology to e-SWIR wavelengths. In order to increase the available conduction band offsets (CBOs), we suggest incorporating nitrogen (N) atoms into the quantum well material. The incorporation of N atoms into III-Vs results in dilute-nitride highly mismatched alloys with lower bandgaps and higher CBOs. In our work, we demonstrate CBO values reaching up to ∼1 eV in InGaAsN/AlGaAs QWIPs. This large CBO makes these structures suitable for e-SWIR detection. The large CBO reduces the dark current dramatically and allows efficient detection at room temperature.In our study, we devised two similar InGaAsN/AlGaAs QWIP devices with twofold, 1% and 2% N composition …

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Jan 2019 • Scientific reports

Remote photoacoustic sensing using speckle-analysis

Benjamin Lengenfelder, Fanuel Mehari, Martin Hohmann, Markus Heinlein, Erika Chelales, Maximilian J Waldner, Florian Klämpfl, Zeev Zalevsky, Michael Schmidt

Laser surgery is a rising surgical technique, which offers several advantages compared to the traditional scalpel. However, laser surgery lacks a contact-free feedback system which offers high imaging contrast to identify the tissue type ablated and also a high penetration depth. Photoacoustic imaging has the potential to fill this gap. Since photoacoustic detection is commonly contact based, a new non-interferometric detection technique based on speckle-analysis for remote detection is presented in this work. Phantom and ex-vivo experiments are carried out in transmission and reflection-mode for proof of concept. In summary, the potential of the remote speckle sensing technique for photoacoustic detection is demonstrated. In future, this technique might be applied for usage as a remote feedback system for laser surgery, which could help to broaden the applications of lasers as smart surgical tools.

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Jan 2019 • Cell death & disease

sPIF promotes myoblast differentiation and utrophin expression while inhibiting fibrosis in Duchenne muscular dystrophy via the H19/miR-675/let-7 and miR-21 pathways

Daria Morgoulis, Peter Berenstein, Simona Cazacu, Gila Kazimirsky, Amir Dori, Eytan R Barnea, Chaya Brodie

Duchenne muscular dystrophy (DMD) is a progressive, lethal, X-linked disease of skeletal and cardiac muscles caused by mutations in the dystrophin gene. Loss of dystrophin leads to muscle fiber damage and impairment of satellite cell asymmetric division, which are essential for muscle regeneration. These processes ultimately result in muscle wasting and the replacement of the degenerating muscles by fibrogenic cells, a process that leads to the generation of fibrotic tissues. Preimplantation factor (PIF) is an evolutionary conserved 15-amino acid peptide secreted by viable mammalian embryos. Synthetic PIF (sPIF) reproduces the protective/regenerative effects of the endogenous peptide in immune disorders and transplantation models. In this study, we demonstrated that sPIF treatment promoted mouse and human myoblast differentiation and inhibited the expression of collagen 1A1, collagen 1A2, and TGF-β …

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Jan 2019 • Nanomedicine

Zn-doped CuO nanocomposites inhibit tumor growth by NF-κB pathway cross-linked autophagy and apoptosis

Huanli Xu, Ru Yuan, Xiaohui Liu, Xiao Li, Gan Qiao, Cong Li, Aharon Gedanken, Xiukun Lin

Aim: To investigate the antitumor effects and action mechanism of Zn-doped CuO nanocomposites (Zn-CuONPs). Materials & methods: Therapeutic effects and mechanisms of Zn-CuONPs were investigated both in vitro and in vivo. Results: Zn-CuONPs could inhibit tumor growth both in vitro and in vivo significantly. Zn-CuONPs treatment resulted in cytotoxicity, reactive oxygen species (ROS) production, DNA damage, apoptosis and autophagy. ROS scavenger N-acetylcysteine attenuated all of the above effects induced by Zn-CuONPs. N-acetylcysteine also restored the effects of Zn-CuONPs on protein expressions related to apoptosis, autophagy and NF-κB pathways. NF-κB pathway inhibitor pyrrolidine dithiocarbamate significantly attenuated Zn-CuONPs induced apoptosis and autophagy. Conclusion: Our data demonstrated that Zn-CuONPs could inhibit tumor growth both in vitro and in vivo by ROS-dependent …

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Elasticity and Depth Measurement using Both Secondary Speckle and Time Multiplexing Interference.

Ariel Schwarz, Nisan Ozana, Amir Shemer, Ran Califa, Hadar Genish, Zeev Zalevsky

In this paper, we describe a technique for elasticity and depth measurement via both secondary speckle and time multiplexing interference approach. Using external stimulation of elastic medium (in example: human tissue) by infra-sonic vibration, photons from different depths of the elastic medium were separated. In addition, this work uses a modulated laser that incorporates at the same scanning time, a speckle pattern tracking method for sensing surface tilting and interferometer method for sensing z-axis movements. In this paper, we present preliminary experiments showing the ability to separate data of light coming from different layers in the elastic medium.

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2019 • Nanoscale

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Yevgeny Rakita, Igor Lubomirsky, David Cahen

2019 • ChemNanoMat

Enantioselective colloidosomes based on chiral silica nanoparticles

Gila Levi, Yitzhak Mastai

Pickering emulsion is one of the principal methods for the formation of colloidosomes, offering a high level of control over their size and permeability. In this article, we describe the synthesis of chiral colloidosomes based on chiral silica nanoparticles produced in a sol‐gel process combining a chiral (S)‐N‐1‐phenylethyl‐N′‐triethoxysilylpropylurea precursor with tetraethyl orthosilicate. Chiral colloidosomes with a typical diameter of 1.7 μm were obtained from Pickering assembly of partially hydrophobized nanoparticles, as confirmed by electron microscopy and FTIR spectroscopy. The enantioselectivity of the silica colloidosomes was confirmed by enantioselective adsorption of racemic dichlorprop herbicide solutions onto the capsules, as proved by circular dichroism spectroscopy. Similar chiral colloidosomes could be synthesized in this facile and low‐cost method, which are expected to be of interest in various …

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