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May 2019 • AAMAS, 2303-2305, 2019

Is Agent Software More Complex than Other Software?

Alon Zanbar, Gal A Kaminka

We empirically investigate agent software repositories using commonly used software metrics, which are used in software engineering literature to quantify meaningful characteristics of software based on its source code. We contrast the measurements with those of software in other categories. Analyzing hundreds of software projects, we nd that agent software may be di erent from other types of software, in terms of software complexity measures.

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May 2019 • Journal of Cell Biology

Active RNA polymerase II curbs chromatin movement

Hodaya Hochberg-Laufer, Yaron Shav-Tal

Chromosomes are not very mobile during interphase. In this issue, Nagashima et al. (2019. J. Cell Biol. propose that the overall stabilization of genome structure is achieved by loose connections between DNA regions brought about by transcriptionally active RNA polymerases.

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May 2019 • Proceedings Sixth International Conference Boulder, Colorado, July 12–16 …, 2019

Collisional Redistribution of Radiation in Intense Laser Fields

Yitzhak Rabin, Shaul Mukamel

The following diagram (Fig. l) illustrates the place of the present problem within the scope of the more general framework of collisions in the presence of strong radiation fields.

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May 2019 • Journal of The Electrochemical Society

Enhancement of Palladium HOR Activity in Alkaline Conditions through Ceria Surface Doping

Valeria Yarmiayev, Maria Alesker, Anya Muzikansky, Melina Zysler, David Zitoun

Hydrogen oxidation reaction (HOR) electrocatalysis suffers from slow kinetics at the anode of alkaline exchange membrane fuel cells (AEMFCs). A series of Pd-CeO 2-x catalyst was synthesized at low temperature by the decomposition of cerium ammonium nitrate (CAN) on Pd. This simple method yields palladium with sub-stoichiometric amorphous CeO 2-x islands which nucleate and grow on the surface of Pd. The vertical growth is preferred: ceria on ceria vs. ceria on palladium as evidenced by the constant values of Pd electrochemical surface areas observed for all ceria contents. The HOR activity is enhanced compared to pristine Pd. At 0.1 V vs. RHE, the specific and mass activities could be increased by a factor of 100 and 50 respectively for the highest content ceria samples. These results show that high ceria doping is requested to activate the HOR activity of palladium in alkaline medium, which can be …

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May 2019 • ECS Meeting Abstracts

The Feasibility of Energy Extraction from Acidic Wastewater By Capacitive Mixing with a Molecular-Sieving Carbon Cathode

Barak Shapira, Eran Avraham, Doron Aurbach

Capacitive mixing is a newly emerging technique for the production of renewable energy from differences in salinity. The method is based on the controlled mixing of two streams with different salt concentrations which are alternatingly brought into contact with pre-charged porous electrodes, taking advantage of the fact that modification of the electrical double layer of the electrodes results in changes in the solution salinity. In most research, the renewable energy resources are seawater and river water. Here, we demonstrate that energy extraction by capacitive mixing can take place with acidic wastewater and seawater as energy resources. This concept is proved by means of the fabrication of a proton-selective carbon cathode (the negatively polarized electrode), achieved by carbonation of cellulose filter paper, followed by mild activation in concentrated nitric acid. Considerable energy extraction was …

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May 2019 • Energy Storage Materials

Atomic surface reduction of interfaces utilizing vapor phase approach: High energy LiNixMnyCoz oxide as a test case

Eliran Evenstein, Shira Haber, Hadar Sclar, Lothar Houben, Kevin Leung, Michal Leskes, Malachi Noked

In the present work, a simple and agile methodology for atomic surface reduction of interfaces is introduced. Using a surface directed vapor phase reaction, at relatively low temperature, we show that a highly reactive and volatile molecule can be used to selectively reduce the interface, without changing the bulk of the treated material, and without the need of alternating sequence of multiple precursors, normally involved in ALD. The model system we use to demonstrate the efficacy, and potential of our approach is trimethyl aluminum, and high energy Li and Mn rich cathode (HE-NCM) as the functional material of interest. We demonstrate that with the proposed method, the particles of HE-NMC were conformally coated with ~ 3 nm amorphous layer of the reduced surface in less than 1 h (including the cooling time),as witnessed using HR-TEM. XPS and solid-state NMR, further confirmed that surface treatment was …

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May 2019 • IEEE

Remote photonic sensing of cerebral hemodynamics via spatial-temporal analysis of back-scattered laser light

N Ozana, JA Noah, X Zhang, Yumie Ono, J Hirsch, Z Zalevsky

The ability to remotely extract cerebral hemodynamics from specific locations on the brain using time varied speckle patterns is innovative. The first step towards remote sensing of brain activity and stroke is presented.

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

Towards Predictive Execution Monitoring in BDI Recipes

Mika Barkan, Gal A Kaminka

Agents do not only generate and choose plans for execution, they also monitor the execution of plans and handle contingencies [1, 5, 6]. The capacity for execution monitoring allows agents to assess the execution of plans, determine the need for re-planning, identify opportunities, and re-evaluate goal selection. In practice, many BDI plan execution systems focus only on the current plan step. They do not project ahead the current knowledge of the agent to determine implications on future steps. Thus a failure of a future plan-step, which may already be predictable with given the current knowledge of the agent, is not detected until the last possible moment.This paper examines the task of predictive execution monitoring in BDI recipes. Such capability is similar in principle to BDI planning [4, 7, 8], in the sense that both tasks require prediction of future states, based on simulation of actions taken. However, monitoring of recipes does not require ordering decisions, this is already defined by the structure of the recipe, and would seem to therefore require lighter computation. Alas, this is not the case. We discuss a base algorithm for predictive execution monitoring, intended for hierarchical recipes. We show that its complexity is super-exponential in the general case. We then discuss several methods for reducing the projected execution space. We evaluated these methods in various combinations in hundreds of experiments.

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May 2019 • ACS omega

Engineering of durable antifog thin coatings on plastic films by UV-curing of proteinoid prepolymers with PEG-diacrylate monomers

Elisheva Sason, Michal Kolitz-Domb, Jordan H Chill, Shlomo Margel

Fog formation on transparent surfaces constitutes a major challenge in several optical applications, such as plastic packaging, lenses, mirrors, and windshields. To overcome this problem, we prepared and characterized durable antifog thin coatings on plastic films such as polyethylene terephthalate (PET). Proteinoids are biocompatible random polymers made of α-amino acids by thermal step-growth polymerization. Proteinoid prepolymers were prepared by adding activated double bonds to proteinoids via the Michael addition reaction. A series of thin antifog cross-linked coatings were prepared by spreading on PET films with a Mayer rod various mixtures of the proteinoid prepolymers, polyethylene glycol diacrylate, and a photoinitiator, followed by UV-curing of the dried coatings. The antifog properties of the coatings were determined by the contact angle, roughness, haze, and gloss measurements, as well as hot …

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May 2019 • Journal of Nanoparticle Research

In situ synthesis and catalytic properties of Cu2O 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 • Cytotherapy

Exosomes loaded with PTEN siRNA leads to functional recovery after complete transection of the spinal cord by specifically targeting the damaged area

D Offen, N Perets, S Guo, O Betzer, R Popovtzer, S Ben-Shaul, A Sheinin, I Michaelevski, S Levenberg

Background & AimComplete spinal cord injury (SCI) is a debilitating disease which usually leads to permanent functional impairments, with various complications and limited spontaneous recovery or effective treatment. Here, we report that in rats with complete SCI, intranasal administrations of mesenchymal stem cells-derived exosomes (MSC-Exo) could penetrate the blood-brain barrier, home selectively to the spinal cord lesion, and show affinity to neurons within the lesion. When these exosomes were loaded with phosphatase and tensin homolog small interfering RNA, termed ExoPTEN, they migrated from the nose and silenced PTEN expression in the lesion. Furthermore, the loaded exosomes promoted robust axonal regeneration and angiogenesis, accompanied by decreased astrogliosis and microgliosis. Moreover, the intranasal ExoPTEN treatment partially restored electrophysiological and structural …

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May 2019 • Materials Chemistry and Physics

Ternary nickelcobaltmanganese spinel oxide nanoparticles as heterogeneous electrocatalysts for oxygen evolution and oxygen reduction reaction

P Sivakumar, Palaniappan Subramanian, Thandavarayan Maiyalagan, Aharon Gedanken, Alex Schechter

Multimetallic nanostructure spinels composed of nickel, cobalt, and manganese ions were synthesized and their bifunctional catalytic activity towards oxygen evolution and oxygen reduction reaction in alkaline pH is reported. Three different compositions, namely, NiCoMnO4, Ni1.5Co0.75Mn0.75O4, and Ni2Co0.5Mn0.5O4 were prepared by a simple template-free hydrothermal route followed by a thermal treatment in air at 600 °C. The ORR/OER activity and the stability of these ternary metal oxides strongly depend on the composition of transition metals. The best performing Ni1.5Co0.75Mn0.75O4 catalyst exhibits modest OER and ORR activity with an overpotential difference (ΔE = EORR-EOER) of 0.79 V vs. RHE between two reactions in alkaline solution, comparable to expensive and supported IrO2, Pt catalysts. Electrochemical studies and extensive physical characterizations indicated that amount of …

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May 2019 • CLEO: Science and Innovations, SF2J. 1, 2019

Ultra-Low Loss Integrated Lithium Niobate Photonics in Visible Wavelengths

Boris Desiatov, Amirhassan Shams-Ansari, Mian Zhang, Cheng Wang, Marko Lončar

We demonstrate a low loss integrated photonic platform in lithium niobate in the visible wavelength range. We show microring resonators with a quality factor of 10 7 and gigahertz intensity modulators.

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May 2019 • 2019 Conference on Lasers and Electro-Optics (CLEO), 1-2, 2019

Integrated Silicon Photodetector in Thin Film Lithium Niobate Platform for Visible Wavelength Band

Boris Desiatov, Marko Lončar

We demonstrate design, fabrication and characterization of amorphous silicon photodetector on lithium niobate photonic platform at visible wavelengths. The device shows the best responsivity of 10mA/W and dark current of less than 0.5nA.

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May 2019 • IEEE Photonics Journal

Thermally reconfigurable meta-optics

Tomer Lewi, Nikita A Butakov, Hayden A Evans, Mark W Knight, Prasad P Iyer, David Higgs, Hamid Chorsi, Juan Trastoy, Javier Del Valle Granda, Ilya Valmianski, Christian Urban, Yoav Kalcheim, Paul Y Wang, Philip WC Hon, Ivan K Schuller, Jon A Schuller

Metasurfaces are two-dimensional nanostructures that allow unprecedented control of light through engineering the amplitude, phase, and polarization across meta-atom resonators. Adding tunability to metasurface components would boost their potential and unlock a vast array of new application possibilities such as dynamic beam steering, tunable metalenses, and reconfigurable meta-holograms, to name a few. We present here high-index meta-atoms, resonators, and metasurfaces reconfigured by thermal effects, across the near to mid-infrared spectral ranges. We study thermal tunability in group IV and group IV-VI semiconductors, as well as in phase-transition materials, and demonstrate large dynamic resonance frequency shifts accompanied by significant amplitude and phase modulation in metasurfaces and resonators. We highlight the importance of high-Q resonances along with peak performance of …

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May 2019 • Physical review letters

Coherent superposition of Feshbach dimers and Efimov trimers

Yaakov Yudkin, Roy Elbaz, Panagiotis Giannakeas, Chris H Greene, Lev Khaykovich

A powerful experimental technique to study Efimov physics at positive scattering lengths is demonstrated. We use the Feshbach dimers as a local reference for Efimov trimers by creating a coherent superposition of both states. Measurement of its coherent evolution provides information on the binding energy of the trimers with unprecedented precision and yields access to previously inaccessible parameters of the system such as the Efimov trimers’ lifetime and the elastic processes between atoms and the constituents of the superposition state. We develop a comprehensive data analysis suitable for noisy experimental data that confirms the trustworthiness of our demonstration.

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May 2019 • Nucleic acids research

Uncoupling of nucleo-cytoplasmic RNA export and localization during stress

Hodaya Hochberg-Laufer, Avital Schwed-Gross, Karla M Neugebauer, Yaron Shav-Tal

Eukaryotic cells contain sub-cellular compartments that are not membrane bound. Some structures are always present, such as nuclear speckles that contain RNA-binding proteins (RBPs) and poly(A)+ RNAs. Others, like cytoplasmic stress granules (SGs) that harbor mRNAs and RBPs, are induced upon stress. When we examined the formation and composition of nuclear speckles during stress induction with tubercidin, an adenosine analogue previously shown to affect nuclear speckle composition, we unexpectedly found that it also led to the formation of SGs and to the inhibition of several crucial steps of RNA metabolism in cells, thereby serving as a potent inhibitor of the gene expression pathway. Although transcription and splicing persisted under this stress, RBPs and mRNAs were mislocalized in the nucleus and cytoplasm. Specifically, lncRNA and RBP localization to nuclear speckles was disrupted …

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May 2019 • Biomedical optics express

Moments reconstruction and local dynamic range compression of high order Superresolution Optical Fluctuation Imaging

Xiyu Yi, Sungho Son, Ryoko Ando, Atsushi Miyawaki, Shimon Weiss

Super-resolution optical fluctuation imaging (SOFI) offers a simple and affordable alternative to other super-resolution (SR) imaging techniques. The theoretical resolution enhancement of SOFI scales linearly with the order of cumulants, while the imaging conditions exhibit less photo-toxicity to the living samples as compared to other SR methods. High order SOFI could, therefore, be a method of choice for dynamic live cell imaging. However, due to the cusp-artifacts and dynamic range expansion of pixel intensities, this promise has not been materialized as of yet. Here we investigated and compared high order moments vs. high order cumulant SOFI reconstructions. We demonstrate that even-order moments reconstructions are intrinsically free of cusp artifacts, allowing for a subsequent deconvolution operation to be performed, hence enhancing the resolution even further. High order moments reconstruction …

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May 2019 • IEEE Photonics Journal

Overlapping time-lens array

Avi Klein, Inbar Sibony, Sara Meir, Shir Shahal, Hamootal Duadi, Moti Fridman

We suggest a time-lens array with a filling factor of 200% and increased resolution of 60% without decreasing the number of lenses in the array. This time-lens array is based on a series of orthogonally polarized time-lenses. We investigate the different nonlinear interactions and show that when the pump waves of two adjacent time-lenses have orthogonal states of polarization, it is possible to overlap by 50% without unwanted nonlinear interactions.

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May 2019 • Physical Review B

Quantum thermal Hall effect of chiral spinons on a kagome strip

Pavel Tikhonov, Efrat Shimshoni

We develop a theory for the thermal Hall coefficient in a spin-1 2 system on a strip of kagome lattice, where a chiral spin-interaction term is present. To this end, we model the kagome strip as a three-leg X X Z spin-ladder, and use bosonization to derive a low-energy theory for the spinons in this system. Introducing further a Dzyaloshinskii-Moriya interaction (D) and a tunable magnetic field (B), we identify three distinct B-dependent quantum phases: a valence-bond crystal (VBC), a “metallic” spin liquid (MSL), and a chiral spin liquid (CSL). In the presence of a temperature difference Δ T between the top and the bottom edges of the strip, we evaluate the net heat current J h along the strip, and consequently the thermal Hall conductivity κ x y. We find that the VBC-MSL-CSL transitions are accompanied by a pronounced qualitative change in the behavior of κ x y as a function of B. In particular, analogously to the quantum …

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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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