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May 2019 • Review of Scientific Instruments

Scanning SQUID microscopy in a cryogen-free cooler

Yishai Shperber, Naor Vardi, Eylon Persky, Shai Wissberg, Martin E Huber, Beena Kalisky

Scanning superconducting quantum interference device (SQUID) microscopy is a powerful tool for investigating electronic states at surfaces and interfaces by mapping their magnetic signal. SQUID operation requires cryogenic temperatures, which are typically achieved by immersing the cryostat in liquid helium. Making a transition to cryogen free systems is desirable, but has been challenging, as electric noise and vibrations are increased in such systems. We report on the successful operation of a scanning SQUID microscope in a modified Montana Instruments cryogen-free cooler with a base temperature of 4.3 K. We demonstrate scanning SQUID measurements with flux noise performance comparable to a wet system and correlate the sensor-sample vibrations to the cryocooler operation frequencies. In addition, we demonstrate successful operation in a variety of SQUID operation modes, including mapping …

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May 2019 • Journal of Power Sources

Crossover-tolerant coated platinum catalysts in hydrogen/bromine redox flow battery

Kobby Saadi, Pilkhaz Nanikashvili, Zhanna Tatus-Portnoy, Samuel Hardisty, Victor Shokhen, Melina Zysler, David Zitoun

The hydrogen-bromine redox flow battery's (H2Br2 RFB) advantages of high energy capacity, high round-trip conversion efficiency and low cost, make it an optimal candidate for large-scale energy storage systems. The crossover of bromide species through the membrane degrades the performance of the H2Br2 RFB by poisoning the catalyst responsible for the hydrogen evolution and oxidation reactions. Herein we propose the new concept of a selective catalyst coating layer that mitigates the effect of bromide crossover. The polymerization of dopamine on the catalyst surface yields a nanoscale conformal polydopamine layer which acts as a semi-permeable barrier to block bromide species. The H2Br2 RFB with the coated catalyst shows a low capacity fading of 6% at 300 mA cm−2 after exposure to 4.5 M charged electrolyte for 2 h. Even the beginning of life polarization curves show the benefit of catalyst …

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May 2019 • Optical Society of America

Photoacoustic pulse width measurement using speckle contrast analysis

Matan Benyamin, Hadar Genish, Ran Califa, Nisan Ozana, Ariel Schwartz, Zeev Zalevsky

A previously demonstrated non-expensive setup for remote photoacoustic signal detection, is extended to overcome its bandwidth limitations and obtain time-domain signal properties.

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May 2019 • CLEO: Science and Innovations, SM1N. 2, 2019

Sequence-Coded Coherent Laser Range Finder

Keren Shemer, Gil Bashan, Hagai Diamandi, Yosef London, Arik Bergman, Nadav Levanon, Avi Zadok

A range finder based on an extended sequence of coded pulses is demonstrated. Coherent detection is used to measure the range of weak point reflections, with average energy of only 0.15 photons per code symbol.

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May 2019 • ChemElectroChem

Investigation of Li1.17Ni0.20Mn0.53Co0.10O2 as an Interesting Li‐ and Mn‐Rich Layered Oxide Cathode Material through Electrochemistry, Microscopy, and In …

Prasant Kumar Nayak, Liangtao Yang, Kilian Pollok, Falko Langenhorst, Doron Aurbach, Philipp Adelhelm

Despite their high capacity, Li‐ and Mn‐rich layered oxide cathode materials suffer from capacity fading during prolonged cycling when cycled to potentials higher than 4.5 V vs. Li+/Li. In the work reported herein, we have synthesized the Li‐ and Mn‐rich Li1.17Ni0.20Mn0.53Co0.10O2 cathode material by using a sol‐gel method. The composition and structure are analyzed by ICP, XRD, SEM, and TEM. During testing in half‐cells between 2.5 and 4.6 V vs. Li+/Li at 20 mA g−1, the initial capacity of about 165 mAh g−1 increases during cycling, reaching about 200 mAh g−1 after 30 cycles. The capacity then slowly fades, reaching 188 mAh g−1 after 120 cycles. Also, a high average discharge potential of 3.8 V is obtained, which decreases to 3.6 V after 120 cycles. This study leads to new insights about the effect of Ni concentration on the stability of the Li‐ and Mn‐ rich cathode materials. The in situ …

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May 2019 • Proceedings of the 18th International Conference on Autonomous Agents and …, 2019

Swarms can be rational

Yinon Douchan, Ran Wolf, Gal A Kaminka

Distributed multi-robot systems are comprised of multiple robots, each under its own control. Typically, the robots carry out a tasks towards a global goal. Examples include coverage [1, 6, 14, 22, 35], patrolling [2, 12, 25, 34], foraging [4, 11, 16, 18, 23, 24], order picking [17, 32](made famous by Kiva Systems/Amazon Robotics), and more.A fundamental challenge here is spatial coordination, ie, avoiding and resolving collisions with others. Such coordination necessarily introduces overhead, and therefore both supports and competes with achievement of the goals of the robots. Centralized solutions to managing spatial coordination are computationally intractable [36], and are often not tolerant to mechanical and environment unpredictability (eg, humans in the work area)[32]. Distributed approaches which rely on joint decision-making by the robots (eg,[19, 33] require high communication availability and the capability of robots to assess not just their own state, but those of others. Thus a promising line of research explores swarm

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May 2019 • ACS applied energy materials

Improving Performance of LiNi0.8Co0.1Mn0.1O2 Cathode Materials for Lithium-Ion Batteries by Doping with Molybdenum-Ions: Theoretical and Experimental …

Francis Amalraj Susai, Daniela Kovacheva, Arup Chakraborty, Tatyana Kravchuk, R Ravikumar, Michael Talianker, Judith Grinblat, Larisa Burstein, Yaron Kauffmann, Dan Thomas Major, Boris Markovsky, Doron Aurbach

The work reported herein is an important continuation of our recent experimental and computational studies on Li[NixCoyMnz]O2 (x + y + z = 1) cathode materials for Li-ion batteries, containing minor amounts of multivalent cationic dopants like Al3+, Zr4+, W6+, Mo6+. On the basis of DFT calculations for LiNi0.8Co0.1Mn0.1O2, it was concluded that Mo6+ cations preferably substitute Ni cations in the layered structure due to the lowest substitution energy compared to Li, Co, and Mn. It was established that the electrochemical behavior of LiNi0.8Co0.1Mn0.1O2 as a positive electrode material for Li-ion batteries can be substantially improved by doping with 1–3 mol % of Mo6+, in terms of lowering the irreversible capacity loss during the first cycle, increasing discharge capacity and rate capability, decreasing capacity fade upon prolonged cycling, and lowering the voltage hysteresis and charge-transfer resistance. The …

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May 2019 • Cytotherapy

Targeting damages in the brain: exosomes derived from MSC present migration and homing abilities to different neurodegenerative and neuropsychiatric locations

D Offen, N Perets, O Betzer, R Popovtzer, R Shapira, U Ashery

Background & AimOne of the greatest challenges in both neurology and psychiatry is targeted drug delivery. Most of the molecules do not cross the blood-brain barrier, and those who cross it do not target the damaged area in the brain and causes major side effect and non-specific changes.Mesenchymal stem cells (MSC) are known to have migration abilities to inflammatory regions. They also have the potential of immunomodulation in the damaged tissue and promote regeneration. The therapeutic effects of MSC are known to be mediated mainly via the secretion of factors and vesicles to the tissues. Exosomes are small nano-vesicles containing genetic information and are used as cell-to-cell communication. Here we that exosomes secreted from MSC (MSC-exo) have migration abilities to distinct pathological areas in the brain, also when they are given through intranasal administration …

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May 2019 • Journal of Physics D: Applied Physics

An investigation of the influence of thermal process on the electrical conductivity of LIFT printed Cu structures

O Fogel, G Bernstein Toker, G Cohen-Taguri, P Gergaud, F Gaillard, Z Kotler, Z Zalevsky

The electrical properties of copper tracks printed by laser-induced-forward-transfer (LIFT) are typically inferior to the bulk values. Several limiting factors have been indicated such as oxidation, droplet boundaries and grain boundaries. However, the relative contribution of each of these factors has not been determined. To improve the electrical properties of LIFT printed structures, an analysis of various factors is essential. Here, we concentrate on the effect of post-printing thermal treatment on LIFT printed copper structures. A reduction in electrical resistivity by a factor of~ 3 is obtained resulting in a value lower than 3 times the bulk copper value (1.68 µΩ centerdot cm). Real time resistance measurements indicate that an efficient thermal annealing can be achieved at 200 C–300 C within a couple of minutes. The morphological changes associated with such thermal treatment were analyzed using HR-SEM and XRD …

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May 2019 • CLEO: QELS_Fundamental Science, FM1M. 3, 2019

Integration of quantum emitters with lithium niobate photonics

Shahriar Aghaeimeibodi, Boris Desiatov, Je-Hyung Kim, Chang-Min Lee, Mustafa Atabey Buyukkaya, Aziz Karasahin, Christopher JK Richardson, Richard P Leavitt, Marko Lončar, Edo Waks

We demonstrate integration of telecom quantum dots with lithium niobate photonics using a pick-and-place technique. Second order photon correlation measurement performed with an on-chip beamsplitter confirms the single-photon nature of the emission.

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May 2019 • CLEO: QELS_Fundamental Science, FF1A. 7, 2019

Quantum illumination with x-rays

S Sofer, E Strizhevsky, A Schori, K Tamasaku, S Shwartz

We present the experimental realization of quantum illumination with x-rays. By using entangled photons, we detected the presence of an object in a noisy environment and improved the visibility substantially compared to classical methods.

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May 2019 • IEEE

Improving the Temporal Resolution of Speckle based Remote Phonocardiogram Sensing via Laser Modulation

N Ozana, Z Markman, R Califa, Z Zalevsky

We present a method for remote phonocardiogram sensing which employs temporal modulation of the illumination laser. This method yields a significant enhancement of the temporal bandwidth of the captured speckle image sequence, thus improving performance.

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May 2019 • Journal of Nanoparticle Research

In situ synthesis and catalytic properties of Cu 2 O nanoparticles based on clay materials and polyethylene glycol

Ainur N Imangaliyeva, Yitzhak Mastai, Gulziya A Seilkhanova

A novel protocol for in situ synthesis of Cu2O nanoparticles immobilized on natural bentonite and zeolite and functionalized by polyethylene glycol is reported. The NPs were synthesized during the course of the catalytic reduction of 4-nitrophenol in the presence of NaBH4. The synthesized precursors and the catalysts Cu2O/PEG-BT and Cu2O/PEG-ZT were characterized by X-ray diffraction, high-resolution scanning electron microscopy, energy-dispersive X-ray and atomic absorption spectroscopy, surface area analysis, and UV-visible spectroscopy. The diffraction and microscopy data confirmed that in situ copper oxide (I) NPs were synthesized with a size range of 20 to 40 nm. The reduction rate constants at 25 °C for Cu2O/PEG-BT and Cu2O/PEG-ZT were 1.22 × 10−2 and 1.79 × 10−2 s−1, respectively. The synthesized catalysts were found to be highly effective and inexpensive …

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May 2019 • Journal of The Electrochemical Society

SiO2-Modified Separators: Stability in LiPF6-Containing Electrolyte Solutions and Effect on Cycling Performance of Li Batteries

Elena Markevich, Gregory Salitra, M Afri, Joern Kulisch, Pascal Hartmann, Doron Aurbach

Significant improvement in the performance of cells comprising Li metal anodes and LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM 622) cathodes with practical loading of the electrodes material (3.3 mAh cm− 2) and low amount of the electrolyte solution (22 μl cm− 2) was achieved with the use of SiO 2 filled polyethylene separators. The effects of cycling and storage on the stability of the SiO 2 filled separators in fluoroethylene carbonate (FEC) and LiPF 6-containing electrolyte solutions was studied with the use of Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. We analyzed the composition of the separators and the gas phase after storage and cycling of these cells. Although SiO 2 reacts with LiPF 6 when the separator is in contact with the electrolyte solution, we showed that it is fully stable during cycling in the Li-NCM622 cells. The formation of lithium hexafluorosilicate (Li 2 SiF …

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May 2019 • Polymer

Simultaneous polymerization and patterning: A one step acoustic directed assembly method

Silvia Piperno, Haim Sazan, Hagay Shpaisman

Processing materials to form microstructures in the least possible number of steps is desired in order to reduce cost and processing time. In this work, we propose a new approach where standing surface acoustic waves are used to order materials prepared in-situ rather than preformed materials, providing a new method for one-step (simultaneous polymerization and patterning) directed assembly. We demonstrate this concept on products of an ongoing chemical reaction such as polymerization of polydimethylsiloxane (PDMS). We have found that by directed coalescence of nano-sized intermediate nucleation sites, continuous polymeric microstructures are formed. A systematic study of the parameters that control this directed coalescence (cross-linker ratio, salt concentration and acoustic field strength) was performed. Acoustic forces can influence almost all dispersed systems, require low power densities and can …

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Apr 2019 • PLoS computational biology

Gene set meta-analysis with quantitative set analysis for gene expression (QuSAGE)

Hailong Meng, Gur Yaari, Christopher R Bolen, Stefan Avey, Steven H Kleinstein

Small sample sizes combined with high person-to-person variability can make it difficult to detect significant gene expression changes from transcriptional profiling studies. Subtle, but coordinated, gene expression changes may be detected using gene set analysis approaches. Meta-analysis is another approach to increase the power to detect biologically relevant changes by integrating information from multiple studies. Here, we present a framework that combines both approaches and allows for meta-analysis of gene sets. QuSAGE meta-analysis extends our previously published QuSAGE framework, which offers several advantages for gene set analysis, including fully accounting for gene-gene correlations and quantifying gene set activity as a full probability density function. Application of QuSAGE meta-analysis to influenza vaccination response shows it can detect significant activity that is not apparent in individual studies.

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Apr 2019 • Physical Review E

Infinite ergodic theory for heterogeneous diffusion processes

N Leibovich, E Barkai

We show the relation between processes which are modeled by a Langevin equation with multiplicative noise and infinite ergodic theory. We concentrate on a spatially dependent diffusion coefficient that behaves as D (x)∼| x− x ̃| 2− 2/α in the vicinity of a point x ̃, where α can be either positive or negative. We find that a nonnormalized state, also called an infinite density, describes statistical properties of the system. For processes under investigation, the time averages of a wide class of observables are obtained using an ensemble average with respect to the nonnormalized density. A Langevin equation which involves multiplicative noise may take different interpretation, Itô, Stratonovich, or Hänggi-Klimontovich, so the existence of an infinite density and the density's shape are both related to the considered interpretation and the structure of D (x).

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Apr 2019 • ACS Applied Polymer Materials

Carbon-dot initiated synthesis of polypyrrole and polypyrrole@ CuO micro/nanoparticles with enhanced antibacterial activity

Moorthy Maruthapandi, Anjani P Nagvenkar, Ilana Perelshtein, Aharon Gedanken

The carbon dot initiated polypyrrole (PPY) and CuO composite were synthesized into PPY@CuO using a simple one-step sonochemical approach. The synthesized PPY and the PPY@CuO were characterized using Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, 13C-solid-state nuclear magnetic resonance (NMR) spectroscopy, UV–visible spectroscopy, and scanning electron microscopy. A strong interaction was demonstrated between the PPY chains and CuO. This interaction led to changes in the backbone chain of the PPY@CuO composite when compared to the carbon dot initiated PPY. The antibacterial activity against Escherichia coli and Staphylococcus aureus of the carbon dot initiated synthesis of PPY and the sonochemically prepared PPY@CuO composite materials was revealed. The results indicate the biocidal efficacy of PPY@CuO on both Gram-positive and …

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Apr 2019 • Physical Review A

Multiplicative Bell inequalities

Amit Te'eni, Bar Y Peled, Eliahu Cohen, Avishy Carmi

Bell inequalities are important tools in contrasting classical and quantum behaviors. To date, most Bell inequalities are linear combinations of statistical correlations between remote parties. Nevertheless, finding the classical and quantum mechanical (Tsirelson) bounds for a given Bell inequality in a general scenario is a difficult task which rarely leads to closed-form solutions. Here we introduce a class of Bell inequalities based on products of correlators that alleviate these issues. Each such Bell inequality is associated with a unique coordination game. In the simplest case, Alice and Bob, each having two random variables, attempt to maximize the area of a rectangle and the rectangle's area is represented by a certain parameter. This parameter, which is a function of the correlations between their random variables, is shown to be a Bell parameter, ie, the achievable bound using only classical correlations is strictly …

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Apr 2019 • ACS Applied Bio Materials

AS101-loaded PLGA–PEG nanoparticles for autoimmune regulation and chemosensitization

Rahul Kumar Mishra, Vijay Bhooshan Kumar, Lea Monteran, Benjamin Sredni, Aharon Gedanken

The in vivo delivery of therapeutic nanoparticles (NPs) represents a potentially powerful tool that can significantly alter the biological effects of pharmaceutically active compounds. Here, we report on sensitization of tumors to chemotherapy by ammonium trichloro(dioxoethylene-o,o′)tellurate (AS101) encapsulated in NPs, termed AS101-NPs, developed as a composite with the biocompatible and biodegradable copolymer of poly(d,l-lactic-co-glycolic acid)-block-poly(ethylene glycol) (PLGA-b-PEG). AS101 is a potent immunomodulating agent (both in vitro and in vivo) currently undergoing phase II clinical trials for antitumor activity and sensitization of tumors to chemotherapy. Approaches that can control the pharmacokinetic parameters to regulate its clearance from the administered drug delivery system and minimize side effects are of prodigious importance. A strategy to synthesize AS101-NPs by …

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Apr 2019 • Frontiers in psychiatry

Adenosine-to-inosine RNA editing within corticolimbic brain regions is regulated in response to chronic social defeat stress in mice

Alec LW Dick, Khen Khermesh, Evan Paul, Fabian Stamp, Erez Y Levanon, Alon Chen

Adenosine to inosine (A-to-I) RNA editing is a co/post-transcriptional modification of double stranded RNA, catalysed by the adenosine deaminase acting on RNA (ADAR) family of enzymes, which results in recognition of inosine as guanosine by translational and splicing machinery causing potential recoding events in amino acid sequences. A-to-I editing is prominent within brain-specific transcripts and dysregulation of editing at several well-studied loci (e.g., Gria2, Htr2c) has been implicated in acute and chronic stress in rodents as well as neurological (e.g., Alzheimer’s) and psychopathological disorders such as schizophrenia and major depressive disorder. However, only a small fraction of recoding sites has been investigated within the brain following stress and our understanding of the role of RNA editing in transcriptome regulation following environmental stimuli remains poorly understood. Thus, we aimed to investigate A-to-I editing at hundreds of loci following chronic social defeat stress (CSDS) in mice within cortico-limbic regions responsive to chronic stress regulation. Adult male mice were subjected to CSDS or control conditions for 21 days and dynamic regulation of A-to-I editing was investigated 2 and 8 days following the final defeat within both the medial prefrontal cortex (mPFC) and basolateral amygdala (BLA). Employing a targeted resequencing approach, which utilises microfluidics-based multiplex PCR coupled with next-generation sequencing, we analysed A-to-I editing at ~100 high confidence editing sites within the mouse brain. CSDS resulted in acute regulation of transcripts encoding several ADAR enzymes, which …

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