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Aug 2021 • Batteries & Supercaps

Molecular Layer Deposition of Alucone Thin Film on LiCoO2 to Enable High Voltage Operation

Ortal Lidor-Shalev, Nicole Leifer, Michal Ejgenberg, Hagit Aviv, Ilana Perelshtein, Gil Goobes, Malachi Noked

Extracting the theoretically high capacity of LiCoO2 (LCO) is desirable for enhancing the energy density of currently used lithium‐ion batteries (LIBs) for portable devices. The bottleneck for exhibiting the high capacity is associated with the limited cut‐off positive voltages beyond which degradation of electrode/electrolyte takes place. In this work, we apply hybrid organic‐inorganic alucone thin film grown directly on LCO by a molecular layer deposition (MLD) method, using sequential exposure to Al‐based and organic‐based precursors. The alucone thin films enabled the high voltage operation of the LCO cathode (> 4.5 V), acting as a protection layer. Electrochemical studies proved that alucone coated LCO show enhanced electrochemical performances with improved cycling stability and enhanced specific capacity, relative to uncoated LCO. Amongst the studied films, 10 nm ethylene glycol/Al coated LCO have …

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Aug 2021 • Nonlinear Optics, NW2B. 4, 2021

Vector Properties of Forward Stimulated Brillouin Scattering in Standard Single-Mode Fibers

Hilel Hagai Diamandi, Gil Bashan, Yosef London, Keren Shemer, Kavita Sharma, Elad Zehavi, Avi Zadok

Torsional-radial guided acoustic modes in standard single-mode fibers are stimulated by pump tones of linear and orthogonal polarizations. The same acoustic modes induce photo-elastic birefringence. Circularly polarized pump waves can generate acoustic vortex beams.

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Aug 2021 • Elife

Expanding the MECP2 network using comparative genomics reveals potential therapeutic targets for Rett syndrome

Irene Unterman, Idit Bloch, Simona Cazacu, Gila Kazimirsky, Bruria Ben-Zeev, Benjamin P Berman, Chaya Brodie, Yuval Tabach

Inactivating mutations in the Methyl-CpG Binding Protein 2 (MECP2) gene are the main cause of Rett syndrome (RTT). Despite extensive research into MECP2 function, no treatments for RTT are currently available. Here, we used an evolutionary genomics approach to construct an unbiased MECP2 gene network, using 1028 eukaryotic genomes to prioritize proteins with strong co-evolutionary signatures with MECP2. Focusing on proteins targeted by FDA-approved drugs led to three promising targets, two of which were previously linked to MECP2 function (IRAK, KEAP1) and one that was not (EPOR). The drugs targeting these three proteins (Pacritinib, DMF, and EPO) were able to rescue different phenotypes of MECP2 inactivation in cultured human neural cell types, and appeared to converge on Nuclear Factor Kappa B (NF-kB) signaling in inflammation. This study highlights the potential of comparative genomics to accelerate drug discovery, and yields potential new avenues for the treatment of RTT.

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Aug 2021 • The Journal of Physical Chemistry B

Molecular Dynamics Simulations of the Apo and Holo States of the Copper Binding Protein CueR Reveal Principal Bending and Twisting Motions

Renana Schwartz, Sharon Ruthstein, Dan Thomas Major

Copper is essential for proper functioning of cells but is dangerous in unregulated concentrations. One of the members in the bacterial system responsible for facilitating copper homeostasis is the copper efflux regulator (CueR) protein. Upon copper binding, CueR induces transcription of additional copper homeostasis proteins via a cascade of events. There are some available crystal structures of CueR, in the holo (copper-bound), active (copper- and DNA-bound), and repressed (only DNA-bound) states, and these structures suggest that transcription initiation involves a distortion in the promoter DNA strand. In this work, we study the dynamic behavior of the protein, using molecular dynamics simulations, and compare with available electron paramagnetic resonance measurements for validation. We develop simple force-field parameters to describe the copper-binding motif, thus enabling the use of simplified …

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Aug 2021 • arXiv preprint arXiv:2108.13047

Measurement induced quantum walks

A Didi, E Barkai

We investigate a tight binding quantum walk on a graph. Repeated stroboscopic measurements of the position of the particle yield a measured "trajectory", and a combination of classical and quantum mechanical properties for the walk are observed. We explore the effects of the measurements on the spreading of the packet on a one dimensional line, showing that except for the Zeno limit, the system converges to Gaussian statistics similarly to a classical random walk. A large deviation analysis and an Edgeworth expansion yield quantum corrections to this normal behavior. We then explore the first passage time to a target state using a generating function method, yielding properties like the quantization of the mean first return time. In particular, we study the effects of certain sampling rates which cause remarkable change in the behavior in the system, like divergence of the mean detection time in finite systems and a decomposition of the phase space into mutually exclusive regions, an effect that mimics ergodicity breaking, whose origin here is the destructive interference in quantum mechanics. For a quantum walk on a line we show that in our system the first detection probability decays classically like , this is dramatically different compared to local measurements which yield a decay rate of , indicating that the exponents of the first passage time depends on the type of measurements used.

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Aug 2021 • Nanomaterials

Graphene oxide and reduced graphene oxide nanoflakes coated with glycol chitosan, propylene glycol alginate, and polydopamine: Characterization and cytotoxicity in human …

Lorenzo Vannozzi, Enrico Catalano, Madina Telkhozhayeva, Eti Teblum, Alina Yarmolenko, Efrat Shawat Avraham, Rajashree Konar, Gilbert Daniel Nessim, Leonardo Ricotti

Recently, graphene and its derivatives have been extensively investigated for their interesting properties in many biomedical fields, including tissue engineering and regenerative medicine. Nonetheless, graphene oxide (GO) and reduced GO (rGO) are still under investigation for improving their dispersibility in aqueous solutions and their safety in different cell types. This work explores the interaction of GO and rGO with different polymeric dispersants, such as glycol chitosan (GC), propylene glycol alginate (PGA), and polydopamine (PDA), and their effects on human chondrocytes. GO was synthesized using Hummer’s method, followed by a sonication-assisted liquid-phase exfoliation (LPE) process, drying, and thermal reduction to obtain rGO. The flakes of GO and rGO exhibited an average lateral size of 8.8 ± 4.6 and 18.3 ± 8.5 µm, respectively. Their dispersibility and colloidal stability were investigated in the presence of the polymeric surfactants, resulting in an improvement in the suspension stability in terms of average size and polydispersity index over 1 h, in particular for PDA. Furthermore, cytotoxic effects induced by coated and uncoated GO and rGO on human chondrocytes at different concentrations (12.5, 25, 50 and 100 µg/mL) were assessed through LDH assay. Results showed a concentration-dependent response, and the presence of PGA contributed to statistically decreasing the difference in the LDH activity with respect to the control. These results open the way to a potentially safer use of these nanomaterials in the fields of cartilage tissue engineering and regenerative medicine.

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Aug 2021 • ACS Applied Materials & Interfaces

Fluorine-Free Superhydrophobic Coating with Antibiofilm Properties Based on Pickering Emulsion Templating

Mor Maayan, Karthik Ananth Mani, Noga Yaakov, Michal Natan, Gila Jacobi, Ayelet Atkins, Einat Zelinger, Elazar Fallik, Ehud Banin, Guy Mechrez

This study presents antibiofilm coating formulations based on Pickering emulsion templating. The coating contains no bioactive material because its antibiofilm properties stem from passive mechanisms that derive solely from the superhydrophobic nature of the coating. Moreover, unlike most of the superhydrophobic formulations, our system is fluorine-free, thus making the method eminently suitable for food and medical applications. The coating formulation is based on water in toluene or xylene emulsions that are stabilized using commercial hydrophobic silica, with polydimethylsiloxane (PDMS) dissolved in toluene or xylene. The structure of the emulsions and their stability was characterized by confocal microscopy and cryogenic-scanning electron microscopy (cryo-SEM). The most stable emulsions are applied on polypropylene (PP) surfaces and dried in an oven to form PDMS/silica coatings in a process called …

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Aug 2021 • Physical Review B

Measurements of polarization dependencies in parametric down-conversion of x rays into ultraviolet radiation

S Sofer, O Sefi, AGA Nisbet, S Shwartz

We present measurements of the polarization dependencies of the x-ray signal photons generated by the effect of parametric down-conversion of x rays into ultraviolet radiation. The results exhibit pronounced discrepancies with the classical model for the nonlinearity but qualitatively agree with a recently developed quantum mechanical theory for the nonlinear interaction. Our work shows that the reconstruction of the atomic scale charge distribution of valence electrons in crystals by using nonlinear interaction between x rays and longer wavelength radiation, as was suggested in previous works, requires the knowledge of polarization of the generated x-ray signal beam. The results presented in this work indicate a methodology for the study of properties of the Wannier functions in crystals.

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Aug 2021 • arXiv preprint arXiv:2108.06778

Discrete sampling of correlated random variables modifies the long-time behavior of their extreme value statistics

Lior Zarfaty, Eli Barkai, David A Kessler

We consider the extreme value statistics of correlated random variables that arise from a Langevin equation. Recently, it was shown that the extreme values of the Ornstein-Uhlenbeck process follow a different distribution than those originating from its equilibrium measure, composed of independent and identically distributed Gaussian random variables. Here, we first focus on the discretely sampled Ornstein-Uhlenbeck process, which interpolates between these two limits. We show that in the limit of large times, its extreme values converge to those of the equilibrium distribution, instead of those of the continuously sampled process. This finding folds for any positive sampling interval, with an abrupt transition at zero. We then analyze the Langevin equation for any force that gives rise to a stable equilibrium distribution. For forces which asymptotically grow with the distance from the equilibrium point, the above conclusion continues to hold, and the extreme values for large times correspond to those of independent variables drawn from the equilibrium distribution. However, for forces which asymptotically decay to zero with the distance, the discretely sampled extreme value statistics at large times approach those of the continuously sampled process.

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Aug 2021 • arXiv preprint arXiv:2108.02726

Quantum logical entropy: fundamentals and general properties

Boaz Tamir, Ismael L Paiva, Zohar Schwartzman-Nowik, Eliahu Cohen

Logical entropy gives a measure, in the sense of measure theory, of the distinctions of a given partition of a set, an idea that can be naturally generalized to classical probability distributions. Here, we analyze how fundamental concepts of this entropy and other related definitions can be applied to the study of quantum systems, leading to the introduction of the quantum logical entropy. Moreover, we prove several properties of this entropy for generic density matrices that may be relevant to various areas of quantum mechanics and quantum information. Furthermore, we extend the notion of quantum logical entropy to post-selected systems.

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Aug 2021 • Available at SSRN 3737807

Decomposition of Individual SNP Patterns From Mixed DNA Samples

Gabriel Azhari, Shamam Waldman, Netanel Ofer, Yosi Keller, Shai Carmi, Gur Yaari

Single Nucleotide Polymorphism markers (SNPs) have great potential to identify individuals, family relations, biogeographical ancestry, and phenotypic traits. In many forensic situations DNA mixtures of a victim and an unknown suspect exist. Extracting from such samples the suspect's SNP profile can be used to assist investigation and gather intelligence. Computational tools to determine inclusion/exclusion of a known individual from a mixture exist, but no algorithm to extract an unknown SNP profile without a list of suspects is available. We present here AH-HA, a novel computational approach for extracting an unknown SNP profile from a whole genome sequencing (WGS) of a two person mixture. It utilizes techniques similar to the ones used in haplotype phasing. It constructs the inferred genotype as an imperfect mosaic of haplotypes from a reference panel of the target population. It is shown to outperform more simplistic approaches, maintaining high performance through a wide range of sequencing depths (500x-5x). AH-HA can be applied in cases of victim-suspect mixtures and improve the capabilities of the investigating forces. This approach can be extended to more complex mixtures, with more donors and less prior information, further motivating the development of SNP based forensics technologies.

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Aug 2021 • Materials Today Chemistry

Engineering of superhydrophobic silica microparticles and thin coatings on polymeric films by ultrasound irradiation

T Iline-Vul, S Bretler, S Cohen, I Perelshtein, N Perkas, A Gedanken, S Margel

Superhydrophobic coatings are one of the recent hot topics in industrial applications as well as academic studies. The mimicking lotus leaves' superhydrophobic properties have been successfully transferred to real-life applications. However, the current preparation methods used to obtain superhydrophobic coatings are still complex, commonly are not transparent and/or not durable. In the present study, a new relatively simple way to prepare superhydrophobic coatings on polymeric films is described. First, superhydrophobic silica microparticles (MPs) were synthesized by fluorination of SiO2 MPs produced by a modified Stöber method. Briefly, tetraethyl orthosilicate was polymerized in an ethanol/water continuous phase under basic conditions, and the resultant SiO2 MPs were dispersed in heptane as a continuous phase and reacted with 1H,1H,2H,2H-perfluorododecyltrichlorosilane (FTS) to yield FTS-SiO2 MPs, which were dried and dispersed in decane. Superhydrophobic thin coatings were then produced by a ‘throwing stones’ sonication technique and deposited onto polycarbonate, polypropylene, polyethylene, and polyurethane films. The coatings are durable, may be transparent, and exhibit self-cleaning properties for the specific practical applications. The MPs and coated polymeric films were characterized by dynamic light scattering, high-resolution scanning electron microscopy, water contact and sliding angle measurements, and infrared and x-ray photoelectron spectroscopy. This ultrasound-assisted coating process may be upscaled and applied to many polymeric films, for instance polymethyl methacrylate, polystyrene, and polyvinyl chloride. Various applications are envisaged, including but not limited to self-cleaning windows, anti-sticking of snow to antennas and windows, solar panels, roof tiles, agricultural applications, corrosion resistance, and anti-biofouling.

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Aug 2021 • Journal of the American Chemical Society

Can Anions Be Inserted into MXene?

Netanel Shpigel, Arup Chakraborty, Fyodor Malchik, Gil Bergman, Amey Nimkar, Bar Gavriel, Meital Turgeman, Chulgi Nathan Hong, Maria R Lukatskaya, Mikhael D Levi, Yury Gogotsi, Dan T Major, Doron Aurbach

Despite the continuous progress in the research and development of Ti3C2Tx (MXene) electrodes for high-power batteries and supercapacitor applications, the role of the anions in the electrochemical energy storage and their ability to intercalate between the MXene sheets upon application of positive voltage have not been clarified. A decade after the discovery of MXenes, the information about the possibility of anion insertion into the restacked MXene electrode is still being questioned. Since the positive potential stability range in diluted aqueous electrolytes is severely limited by anodic oxidation of the Ti, the possibility of anion insertion was evaluated in concentrated aqueous electrolyte solutions and aprotic electrolytes as well. To address this issue, we have conducted in situ gravimetric electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D) measurements in highly concentrated LiCl …

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Aug 2021 • Metamaterials, Metadevices, and Metasystems 2021 11795, 1179511, 2021

Static and active chalcogenide based meta-optics

Tomer Lewi

Chalcogenide based materials are excellent candidates for implementing static and dynamic meta-optics as they possess very high permittivities and support large modulation of optical constants through various mechanisms such as, phase-change, photon-darkening, laser writing and anomalous thermo-optic effects. We present a study of various chalcogenide compositions used for static and active metasurfaces. We start with large area CVD grown amorphous Selenium nanoparticles on various substrates and show that their Mie-resonant response spans the entire mid-infrared range. By coupling Se Mie-resonators to ENZ substrates we demonstrate an order of magnitude increase in quality factor. Next, we investigate topological insulators Bi2Te3 metasurfaces and demonstrate that these high permittivity metasurfaces can yield very large absorption resonances that are tunable in the infrared range. Finally, we …

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Aug 2021 • Physical Review B

Probing the metallic energy spectrum beyond the Thouless energy scale using singular value decomposition

Richard Berkovits

Disordered quantum systems feature an energy scale known as the Thouless energy. For energy ranges below this scale, the properties of the energy spectrum can be described by random matrix theory. Above this scale a different behavior sets in. For a metallic system it was shown long ago by Altshuler and Shklovskii [Sov. Phys. JETP 64, 127 (1986)] that the number variance should increase as a power law with power dependent on only the dimensionality of the system. Although tantalizing hints at this behavior were seen in previous numerical studies, it is quite difficult to verify this prediction using the standard local unfolding methods. Here we use a different unfolding method, ie, singular value decomposition, and establish a connection between the power law behavior of the scree plot (the singular values ranked by their amplitude) and the power law behavior of the number variance. Thus, we are able to …

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Aug 2021 • ACS applied materials & interfaces, 2021

In Operando, Photovoltaic, and Microscopic Evaluation of Recombination Centers in Halide Perovskite-Based Solar Cells

Arava Zohar, Michael Kulbak, Silver H Turren-Cruz, Pabitra K Nayak, Adi Kama, Anders Hagfeldt, Henry J Snaith, Gary Hodes, David Cahen

The origin of the low densities of electrically active defects in Pb halide perovskite (HaP), a crucial factor for their use in photovoltaics, light emission, and radiation detection, remains a matter of discussion, in part because of the difficulty in determining these densities. Here, we present a powerful approach to assess the defect densities, based on electric field mapping in working HaP-based solar cells. The minority carrier diffusion lengths were deduced from the electric field profile, measured by electron beam-induced current (EBIC). The EBIC method was used earlier to get the first direct evidence for the n-i-p junction structure, at the heart of efficient HaP-based PV cells, and later by us and others for further HaP studies. This manuscript includes EBIC results on illuminated cell cross sections (in operando) at several light intensities to compare optoelectronic characteristics of different cells made by different groups …

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Aug 2021 • Physical Review B

Probing the metallic energy spectrum beyond the Thouless energy scale using singular value decomposition

Richard Berkovits

Disordered quantum systems feature an energy scale known as the Thouless energy. For energy ranges below this scale, the properties of the energy spectrum can be described by random matrix theory. Above this scale a different behavior sets in. For a metallic system it was shown long ago by Altshuler and Shklovskii [Sov. Phys. JETP 64, 127 (1986)] that the number variance should increase as a power law with power dependent on only the dimensionality of the system. Although tantalizing hints at this behavior were seen in previous numerical studies, it is quite difficult to verify this prediction using the standard local unfolding methods. Here we use a different unfolding method, ie, singular value decomposition, and establish a connection between the power law behavior of the scree plot (the singular values ranked by their amplitude) and the power law behavior of the number variance. Thus, we are able to …

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Aug 2021 • Advanced Functional Materials 31 (46), 2104887, 2021

Graphene‐Based Nanomaterials for Neuroengineering: Recent Advances and Future Prospective

Raj Kumar, Rossana Rauti, Denis Scaini, Merav Antman‐Passig, Ohad Meshulam, Doron Naveh, Laura Ballerini, Orit Shefi

Graphene unique physicochemical properties made it prominent among other allotropic forms of carbon, in many areas of research and technological applications. Interestingly, in recent years, many studies exploited the use of graphene family nanomaterials (GNMs) for biomedical applications such as drug delivery, diagnostics, bioimaging, and tissue engineering research. GNMs are successfully used for the design of scaffolds for controlled induction of cell differentiation and tissue regeneration. Critically, it is important to identify the more appropriate nano/bio material interface sustaining cells differentiation and tissue regeneration enhancement. Specifically, this review is focussed on graphene‐based scaffolds that endow physiochemical and biological properties suitable for a specific tissue, the nervous system, that links tightly morphological and electrical properties. Different strategies are reviewed to exploit …

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Aug 2021 • WILEY

The role of DYRK1A in B cell immune responses

Liat Stoler Barak, Amalie Grenov, Hadas Hezroni Bravyi, Ayelet Peres, Gur Yaari, Ziv Shulman

Aug 2021 • Journal of The Electrochemical Society

Stability of Current Collectors Against Corrosion in APC Electrolyte for Rechargeable Mg Battery

Sankalpita Chakrabarty, J Alberto Blázquez, Tali Sharabani, Ananya Maddegalla, Olatz Leonet, Idoia Urdampilleta, Daniel Sharon, Malachi Noked, Ayan Mukherjee

Rechargeable magnesium batteries (RMBs) are highly attractive due to their high volumetric capacity, relatively low cost, and enhanced safety. Significant progress in the development of RMBs was the introduction of nonaqueous electrolyte solutions that enable reversible electrodeposition of Mg metal. These solutions contain a unique mixture of organo− aluminum and chloro− aluminum species. While these solutions are shown to be stable during cathodic polarization, the presence of chlorine anions in the solution can promote the corrosion process during the anodic polarization. Among all the cell components, the cathode current collector is most prone to corrosive processes. In this study, we characterize the corrosion behavior of different metallic current collectors in standard APC (All-Phenyl Complex) electrolyte solutions by following their electrochemical response and surface morphology changes during …

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Aug 2021 • Nature Communications

A dynamical quantum Cheshire Cat effect and implications for counterfactual communication

Yakir Aharonov, Eliahu Cohen, Sandu Popescu

Here we report a type of dynamic effect that is at the core of the so called “counterfactual computation” and especially “counterfactual communication” quantum effects that have generated a lot of interest recently. The basic feature of these counterfactual setups is the fact that particles seem to be affected by actions that take place in locations where they never (more precisely, only with infinitesimally small probability) enter. Specifically, the communication/computation takes place without the quantum particles that are supposed to be the information carriers travelling through the communication channel or entering the logic gates of the computer. Here we show that something far more subtle is taking place: It is not necessary for the particle to enter the region where the controlling action takes place; it is enough for the controlled property of the particle,(ie, the property that is being controlled by actions in the control …

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