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Mar 2021 • Advanced Healthcare Materials 10 (5), 2001167, 2021

Construction of enzyme nanoreactors to enable tumor microenvironment modulation and enhanced cancer treatment

Xiaowen Liu, Yu Hao, Rachela Popovtzer, Liangzhu Feng, Zhuang Liu

Enzymes play pivotal roles in regulating and maintaining the normal functions of all living systems, and some of them are extensively employed for diagnosis and treatment of diverse diseases. More recently, several kinds of enzymes with unique catalytic activities have been found to be promising options to directly suppress tumor growth and/or augment the therapeutic efficacy of other treatments by modulating the hostile tumor microenvironment (TME), which is reported to negatively impair the therapeutic efficacy of different cancer treatments. In this review, first a summary is presented on the chemical approaches utilized for the construction of distinct enzyme nanoreactors with well‐retained catalytic performance and reduced immunogenicity. Then, the utilization of such enzyme nanoreactors in attenuating tumor hypoxia, modulating extracellular matrix, and amplifying tumor oxidative stress is discussed in depth …

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Mar 2021 • Journal of the American Chemical Society

Structure and Functionality of an Alkylated LixSiyOz Interphase for High-Energy Cathodes from DNP-ssNMR Spectroscopy

Shira Haber, Rosy, Arka Saha, Olga Brontvein, Raanan Carmieli, Arava Zohar, Malachi Noked, Michal Leskes

Degradation processes at the cathode–electrolyte interface are a major limitation in the development of high-energy lithium-ion rechargeable batteries. Deposition of protective thin coating layers on the surface of high-energy cathodes is a promising approach to control interfacial reactions. However, rational design of effective protection layers is limited by the scarcity of analytical tools that can probe thin, disordered, and heterogeneous phases. Here we propose a new structural approach based on solid-state nuclear magnetic resonance spectroscopy coupled with dynamic nuclear polarization (DNP) for characterizing thin coating layers. We demonstrate the approach on an efficient alkylated LixSiyOz coating layer. By utilizing different sources for DNP, exogenous from nitroxide biradicals and endogenous from paramagnetic metal ion dopants, we reveal the outer and inner surface layers of the deposited artificial …

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Mar 2021 • Journal of Neural Engineering

Cortical responses to prosthetic retinal stimulation are significantly affected by the light-adaptive state of the surrounding normal retina

Tamar Arens-Arad, Rivkah Lender, Nairouz Farah, Yossi Mandel

Objective. Restoration of central vision loss in patients with age-related macular degeneration (AMD) by implanting a retinal prosthesis is associated with an intriguing situation wherein the central prosthetic vision co-exists with natural normal vision. Of major interest are the interactions between the prosthetic and natural vision. Here we studied the effect of the light-adaptive state of the normal retina on the electrical visual evoked potentials (VEPs) arising from the retinal prosthesis. Approach. We recorded electrical VEP elicited by prosthetic retinal stimulation in wild-type rats implanted with a 1 mm photovoltaic subretinal array. Cortical responses were recorded following overnight dark adaption and compared to those recorded following bleaching of the retina by light (520 nm) at various intensities and durations. Main results. Compared to dark-adapted responses, bleaching induced a 2-fold decrease in the …

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Mar 2021 • Journal of Lightwave Technology

Forward stimulated Brillouin scattering analysis of optical fibers coatings

Hilel Hagai Diamandi, Yosef London, Gil Bashan, Keren Shemer, Avi Zadok

The proper function of protective coating layers is essential for the handling and application of brittle optical fibers. The elastic parameters of polymer coatings can be studied through off-line analysis of test samples. However, the monitoring of these properties on a working fiber during service is challenging. In this work, we use forward stimulated Brillouin scattering processes in standard single mode fibers to measure the acoustic velocity in several types of coating layers. Pump light launches short acoustic pulses outward from the core of the fiber. Multiple reflections at the boundaries between cladding and coating, and between coating and air, form a series of delayed acoustic echoes across the core. These echoes are monitored, in turn, by photo-elastic phase modulation of probe light. Data are collected at temperatures between 25–120?°C. The thermal dependence of the acoustic velocities in several coatings …

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Mar 2021 • Nature communications 12 (1), 1-9, 2021

Aging power spectrum of membrane protein transport and other subordinated random walks

Zachary Fox, Eli Barkai, Diego Krapf

Single-particle tracking offers detailed information about the motion of molecules in complex environments such as those encountered in live cells, but the interpretation of experimental data is challenging. One of the most powerful tools in the characterization of random processes is the power spectral density. However, because anomalous diffusion processes in complex systems are usually not stationary, the traditional Wiener-Khinchin theorem for the analysis of power spectral densities is invalid. Here, we employ a recently developed tool named aging Wiener-Khinchin theorem to derive the power spectral density of fractional Brownian motion coexisting with a scalefree continuous time random walk, the two most typical anomalous diffusion processes. Using this analysis, we characterize the motion of voltage-gated sodium channels on the surface of hippocampal neurons. Our results show aging where the power spectral density can either increase or decrease with observation time depending on the specific parameters of both underlying processes.

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Mar 2021 • Physical Review Research

Experimental tests of multiplicative Bell inequalities and the fundamental role of local correlations

Dilip Paneru, Amit Te'eni, Bar Y Peled, James Hubble, Yingwen Zhang, Avishy Carmi, Eliahu Cohen, Ebrahim Karimi

Bell inequalities are mathematical constructs that demarcate the boundary between quantum and classical physics. A new class of multiplicative Bell inequalities originating from a volume maximization game (based on products of correlators within bipartite systems) has been recently proposed. For these new Bell parameters, it is relatively easy to find the classical and quantum, ie, Tsirelson, limits. Here, we experimentally test the Tsirelson bounds of these inequalities using polarization-entangled photons for a different number of measurements (n), each party can perform. For n= 2, 3, 4, we report the experimental violation of local hidden variable theories. In addition, we experimentally compare the results with the parameters obtained from a fully deterministic strategy, and observe the conjectured nature of the ratio. Finally, utilizing the principle of “relativistic independence” encapsulating the locality of uncertainty …

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Mar 2021 • Crystals

Improving compactness of 3d metallic microstructures printed by laser-induced forward transfer

Niv Gorodesky, Sharona Sedghani-Cohen, Ofer Fogel, Amir Silber, Maria Tkachev, Zvi Kotler, Zeev Zalevsky

Laser-induced forward transfer (LIFT) has been shown to be a useful technique for the manufacturing of micron-scale metal structures. LIFT is a high-resolution, non-contact digital printing method that can support the fabrication of complex shapes and multi-material structures in a single step under ambient conditions. However, LIFT printed metal structures often suffer from inferior mechanical, electrical, and thermal properties when compared to their bulk metal counterparts, and often are prone to enhanced chemical corrosion. This is due mostly to their non-compact structures, which have voids and inter-droplet delamination. In this paper, a theoretical framework together with experimental results of achievable compactness limits is presented for a variety of metals. It is demonstrated that compactness limits depend on material properties and jetting conditions. It is also shown how a specific choice of materials can yield compact structures, for example, when special alloys are chosen along with a suitable donor construct. The example of printed amorphous ZrPd is detailed. This study contributes to a better understanding of the limits of implementing LIFT for the fabrication of metal structures, and how to possibly overcome some of these limitations. View Full-Text

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Mar 2021 • Frontiers in behavioral neuroscience

Transcriptome analysis of NPFR neurons reveals a connection between proteome diversity and social behavior

Julia Ryvkin, Assa Bentzur, Anat Shmueli, Miriam Tannenbaum, Omri Shallom, Shiran Dokarker, Jennifer IC Benichou, Mali Levi, Galit Shohat-Ophir

Social behaviors are mediated by the activity of highly complex neuronal networks, the function of which is shaped by their transcriptomic and proteomic content. Contemporary advances in neurogenetics, genomics, and tools for automated behavior analysis make it possible to functionally connect the transcriptome profile of candidate neurons to their role in regulating behavior. In this study we used Drosophila melanogaster to explore the molecular signature of neurons expressing receptor for neuropeptide F (NPF), the fly homologue of neuropeptide Y (NPY). By comparing the transcription profile of NPFR neurons to those of nine other populations of neurons, we discovered that NPFR neurons exhibit a unique transcriptome, enriched with receptors for various neuropeptides and neuromodulators, as well as with genes known to regulate behavioral processes, such as learning and memory. By manipulating RNA editing and protein ubiquitination programs specifically in NPFR neurons, we demonstrate that the proper expression of their unique transcriptome and proteome is required to suppress male courtship and certain features of social group interaction. Our results highlight the importance of transcriptome and proteome diversity in the regulation of complex behaviors and pave the path for future dissection of the spatiotemporal regulation of genes within highly complex tissues, such as the brain.

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Mar 2021 • Electrochemistry Communications

Changes in the interfacial charge-transfer resistance of Mg metal electrodes, measured by dynamic electrochemical impedance spectroscopy

Ran Attias, Ben Dlugatch, Munseok S Chae, Yosef Goffer, Doron Aurbach

The interfacial electrochemical characteristics of unpassivated Mg metal electrodes have been studied using Staircase Galvano Electrochemical Impedance Spectroscopy (SGEIS) in THF/C6H5MgCl/AlCl3 solutions over a wide range of applied dc currents. The results shed light on the mechanism of electrochemical deposition and dissolution of Mg. We found that at the stationary condition (at the OCV, when no current flows) there is a very high interfacial charge-transfer resistance of around 40,000 Ωcm2. The impedance decreases to several hundred Ωcm2 when dynamic, though steady, processes of Mg deposition or dissolution take place. The alternating process through which impedance spectroscopy is measured is superimposed on this system. We show that the high impedance measured at the OCV with a low direct current is due to interfacial adsorption phenomena. However, the adsorption phenomena …

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Mar 2021 • Journal of Experimental Medicine

Inherited SLP76 deficiency in humans causes severe combined immunodeficiency, neutrophil and platelet defects

Atar Lev, Yu Nee Lee, Guangping Sun, Enas Hallumi, Amos J Simon, Keren S Zrihen, Shiran Levy, Tal Beit Halevi, Maria Papazian, Neta Shwartz, Ido Somekh, Sarina Levy-Mendelovich, Baruch Wolach, Ronit Gavrieli, Helly Vernitsky, Ortal Barel, Elisheva Javasky, Tali Stauber, Chi A Ma, Yuan Zhang, Ninette Amariglio, Gideon Rechavi, Ayal Hendel, Deborah Yablonski, Joshua D Milner, Raz Somech

The T cell receptor (TCR) signaling pathway is an ensemble of numerous proteins that are crucial for an adequate immune response. Disruption of any protein involved in this pathway leads to severe immunodeficiency and unfavorable clinical outcomes. Here, we describe an infant with severe immunodeficiency who was found to have novel biallelic mutations in SLP76. SLP76 is a key protein involved in TCR signaling and in other hematopoietic pathways. Previous studies of this protein were performed using Jurkat-derived human leukemic T cell lines and SLP76-deficient mice. Our current study links this gene, for the first time, to a human immunodeficiency characterized by early-onset life-threatening infections, combined T and B cell immunodeficiency, severe neutrophil defects, and impaired platelet aggregation. Hereby, we characterized aspects of the patient's immune phenotype, modeled them with an …

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Mar 2021 • ChemElectroChem 8 (5), 798-811, 2021

Tunnel‐Type Sodium Manganese Oxide Cathodes for Sodium‐Ion Batteries

Munseok S Chae, Yuval Elias, Doron Aurbach

Tunnel‐type sodium manganese oxide is attracting attention as a cheap and earth‐abundant cathode material for sodium‐ion batteries, offering more stable cycling performance than other layered materials due to its special structural ordering. Developments and applications in aqueous and nonaqueous electrolyte solutions are reviewed, and problems and possible solutions are discussed in detail.

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Mar 2021 • Advanced Energy and Sustainability Research

Electrochemical and Thermal Behavior of Modified Li and Mn‐Rich Cathode Materials in Battery Prototypes: Impact of Pentasodium Aluminate Coating and Comprehensive Understanding …

Hadar Sclar, Sandipan Maiti, Nicole Leifer, Noam Vishkin, Miryam Fayena‐Greenstein, Meital Hen, Judith Grinblat, Michael Talianker, Nickolay Solomatin, Ortal Tiurin, Maria Tkachev, Yair Ein‐Eli, Gil Goobes, Boris Markovsky, Doron Aurbach

Mar 2021 • Langmuir

Immobilization of heteroatom-doped carbon dots onto nonpolar plastics for antifogging, antioxidant, and food monitoring applications

P Das, S Ganguly, S Margel, A Gedanken

This work presents the facile synthesis of heteroatom-doped fluorescent carbon quantum dots (C-dots), which could serve as an antioxidant. Herein, nitrogen, phosphorous, and sulfur codoped carbon dots (NPSC-dots) have been synthesized by a single-step hydrothermal strategy. Owing to the radical scavenging activity of the NPSC-dots, they were tested against several methods as well as in practical applications. The antioxidant ability of the NPSC-dots was efficiently utilized on plastic films by coating with these NPSC-dots. For the very first time, NPSC-dots were immobilized onto nonpolar plastic films (polypropylene) via photochemical covalent grafting to extend the shelf life of food items or storage without affecting the quality of plastic films. The NPSC-dot-coated PP film with negligible deterioration of transparency was extensively studied using scanning electron microscopy (SEM), atomic force microscopy …

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Mar 2021 • Langmuir

Higher Ultrasonic Frequency Liquid Phase Exfoliation Leads to Larger and Monolayer to Few-Layer Flakes of 2D Layered Materials

M Telkhozhayeva, E Teblum, R Konar, O Girshevitz, I Perelshtein, H Aviv, ...

Among the most reliable techniques for exfoliation of two-dimensional (2D) layered materials, sonication-assisted liquid-phase exfoliation (LPE) is considered as a cost-effective and straightforward method for preparing graphene and its 2D inorganic counterparts at reasonable sizes and acceptable levels of defects. Although there were rapid advances in this field, the effect and outcome of the sonication frequency are poorly understood and often ignored, resulting in a low exfoliation efficiency. Here, we demonstrate that simple mild bath sonication at a higher frequency and low power positively contributes to the thickness, size, and quality of the final exfoliated products. We show that monolayer graphene flakes can be directly exfoliated from graphite using ethanol as a solvent by increasing the frequency of the bath sonication from 37 to 80 kHz. The statistical analysis shows that ∼77% of the measured graphene …

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Mar 2021 • The Journal of Physical Chemistry C

Direct Probing of Gap States and Their Passivation in Halide Perovskites by High-Sensitivity, Variable Energy Ultraviolet Photoelectron Spectroscopy

Igal Levine, Kohei Shimizu, Alberto Lomuscio, Michael Kulbak, Carolin Rehermann, Arava Zohar, Mojtaba Abdi-Jalebi, Baodan Zhao, Susanne Siebentritt, Fengshuo Zu, Norbert Koch, Antoine Kahn, Gary Hodes, Richard H Friend, Hisao Ishii, David Cahen

Direct detection of intrinsic defects in halide perovskites (HaPs) by standard methods utilizing optical excitation is quite challenging, due to the low density of defects in most samples of this family of materials (≤1015 cm–3 in polycrystalline thin films and ≤1011 cm–3 in single crystals, except melt-grown ones). While several electrical methods can detect defect densities <1015 cm–3, such as deep level transient spectroscopy (DLTS) or thermally stimulated current (TSC), they require preparation of ohmic and/or rectifying electrical contacts to the sample, which not only poses a challenge by itself in the case of HaPs but also may create defects at the contact–HaP interface and introduce extrinsic defects into the HaP. Here, we show that low-energy photoelectron spectroscopy measurements can be used to obtain directly the energy position of gap states in Br-based wide-bandgap (Eg > 2 eV) HaPs. By measuring …

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Mar 2021 • Neuromolecular medicine

Specific susceptibility to COVID-19 in adults with down syndrome

Tomer Illouz, Arya Biragyn, Milana Frenkel-Morgenstern, Orly Weissberg, Alessandro Gorohovski, Eugene Merzon, Ilan Green, Florencia Iulita, Lisi Flores-Aguilar, Mara Dierssen, Ilario De Toma, Hefziba Lifshitz, Stylianos E Antonarakis, Eugene Yu, Yann Herault, Marie-Claude Potier, Alexandra Botté, Randall Roper, Benjamin Sredni, Ronit Sarid, Jacqueline London, William Mobley, Andre Strydom, Eitan Okun

The current SARS-CoV-2 outbreak, which causes COVID-19, is particularly devastating for individuals with chronic medical conditions, in particular those with Down Syndrome (DS) who often exhibit a higher prevalence of respiratory tract infections, immune dysregulation and potential complications. The incidence of Alzheimer’s disease (AD) is much higher in DS than in the general population, possibly increasing further the risk of COVID-19 infection and its complications. Here we provide a biological overview with regard to specific susceptibility of individuals with DS to SARS-CoV-2 infection as well as data from a recent survey on the prevalence of COVID-19 among them. We see an urgent need to protect people with DS, especially those with AD, from COVID-19 and future pandemics and focus on developing protective measures, which also include interventions by health systems worldwide for reducing …

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Mar 2021 • Bulletin of the American Physical Society

Mutually Reinforced Polymer-Graphene Bilayer Membrane for Energy-Efficient Acoustic Transduction

Guoliang Liu, Gabriel Zeltzer, Doron Naveh, Gavriel Speyer, Assad Ullah Khan, Zacary Croft

We present a lightweight, flexible, transparent, and conductive bilayer composite of polyimide and single-layer graphene suspended on the centimeter scale with an unprecedentedly high aspect-ratio of 1e5. The coupling of the two components leads to mutual reinforcement and creates an ultra-strong membrane that supports 30,000 times its own weight. Upon electromechanical actuation, the membrane pushes a massive amount of air and generates high-quality acoustic sound. The energy efficiency is~ 10-100 times better than state-of-the-art electrodynamic speakers. The bilayer membrane’s combined properties of electrical conductivity, mechanical strength, optical transparency, thermal stability, and chemical resistance will promote applications in electronics, mechanics, and optics.

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Mar 2021 • Journal of Applied Physics

Measurements of nanomagnetic bead relaxation dynamics using planar Hall effect magnetometer

Proloy T Das, H Nhalil, M Schultz, A Grosz, L Klein

We study the magnetization dynamics of nanomagnetic beads with a diameter ranging from 80 to 250 nm in frequency and time domains using a high-resolution elliptical planar Hall effect (EPHE) sensor integrated with a fluidic channel. We find that the dynamics are well described with Cole–Cole and exponential decay models for frequency and time domains, respectively. We discuss the potential use of EPHE sensors in lab-on-a-chip applications.

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Mar 2021 • Journal of Neural Engineering

Cortical responses to prosthetic retinal stimulation are significantly affected by the light-adaptive state of the surrounding normal retina

Tamar Arens-Arad, Rivkah Lender, Nairouz Farah, Yossi Mandel

Objective. Restoration of central vision loss in patients with age-related macular degeneration (AMD) by implanting a retinal prosthesis is associated with an intriguing situation wherein the central prosthetic vision co-exists with natural normal vision. Of major interest are the interactions between the prosthetic and natural vision. Here we studied the effect of the light-adaptive state of the normal retina on the electrical visual evoked potentials (VEPs) arising from the retinal prosthesis. Approach. We recorded electrical VEP elicited by prosthetic retinal stimulation in wild-type rats implanted with a 1 mm photovoltaic subretinal array. Cortical responses were recorded following overnight dark adaption and compared to those recorded following bleaching of the retina by light (520 nm) at various intensities and durations. Main results. Compared to dark-adapted responses, bleaching induced a 2-fold decrease in the …

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Mar 2021 • Journal of Colloid and Interface Science

Electrically conductive cotton fabric coatings developed by silica sol-gel precursors doped with surfactant-aided dispersion of vertically aligned carbon nanotubes fillers in …

Valentina Trovato, Eti Teblum, Yulia Kostikov, Andrea Pedrana, Valerio Re, Gilbert Daniel Nessim, Giuseppe Rosace

HypothesisFrom the end of the twentieth century, the growing interest in a new generation of wearable electronics with attractive application for military, medical and smart textiles fields has led to a wide investigation of chemical finishes for the production of electronic textiles (e-textiles).ExperimentsHerein, a novel method to turn insulating cotton fabrics in electrically conductive by the deposition of three-dimensional hierarchical vertically aligned carbon nanotubes (VACNT) is proposed. Two VACNT samples with different length were synthesized and then dispersed in 4-dodecylbenzenesulfonic acid combined with silica-based sol-gel precursors. The dispersed VACNT were separately compounded with a polyurethane thickener to obtain homogeneous spreadable pastes, finally coated onto cotton surfaces by the “knife-over-roll” technique.FindingsShorter VACNT-based composite showed the best electrical …

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Mar 2021 • Applied Nano

Extending the shelf life of strawberries by the sonochemical coating of their surface with nanoparticles of an edible anti-bacterial compound

Belal Abu Salha, Aharon Gedanken

The current paper presents the coating of harvested strawberries with edible nanoparticles of Chitosan. The NPs were formed by the application of ultrasonic waves on an acidic solution of chitosan. In a one-step process the nanoparticles were created and subsequent to their formation they were deposited on the strawberries surface. The shelf life of the NPs coated was compared with the deposition of the same amount of non-sonicated chitosan, ie, coating of individual chitosan molecules on the fruit. The characterization of the coated fruits was carried out by monitoring the weight loss. TSS (total soluble solids), pH, TA (titratable acidity), and Vitamin C. Finally, the freshness of the strawberries was determined by eye observation. In addition, the characterization of the chitosan NPs was also conducted in this study by (DLS) dynamic light scattering and (SEM) scanning electron microscopy. View Full-Text

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