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Dec 2021 • The Journal of Molecular Diagnostics

A magnetic modulation biosensing-based molecular assay for rapid and highly sensitive clinical diagnosis of Coronavirus disease 2019 (COVID-19)

Michael Margulis, Oran Erster, Shira Roth, Michal Mandelboim, Amos Danielli

Rapid and sensitive detection of human pathogens, such as the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is an urgent and challenging task for clinical laboratories. Currently, the gold standard for SARS-CoV-2–specific RNA is based on quantitative RT-PCR (RT-qPCR), which relies on target amplification by Taq polymerase and uses a fluorescent resonance energy transfer–based hydrolysis probe. Although this method is accurate and specific, it is also time consuming. Here, a new molecular assay is described that combines a highly sensitive magnetic modulation biosensing (MMB) system, rapid thermal cycling, and a modified double-quenched hydrolysis probe. In vitro transcribed SARS-CoV-2 RNA targets spiked in PCR-grade water, were used to show that the calculated limit of detection of the MMB-based molecular assay was 1.6 copies per reaction. Testing 309 RNA extracts from …

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Nov 2021 • Journal of the American Chemical Society

High energy density rechargeable batteries based on Li metal anodes. The role of unique surface chemistry developed in solutions containing fluorinated organic co-solvents

Doron Aurbach, Elena Markevich, Gregory Salitra

To date, lithium ion batteries are considered as a leading energy storage and conversion technology, ensuring a combination of high energy and power densities and prolonged cycle life. A critical point for elaboration of high energy density secondary Li batteries is the use of high specific capacity positive and negative electrodes. Among anode materials, Li metal anodes are considerably superior due to having the highest theoretical specific capacity (3860 mAh g–1) and lowest negative redox potential (−3.040 V vs a standard hydrogen electrode). Combination of Li metal anodes with Li[NiCoM]O2-layered cathodes with a high stable specific capacity of about 200 up to 250 mAh g–1 is particularly attractive. The development of advanced electrolyte solutions which ensure effective passivation of the electrodes’ surfaces is of critical importance. Considerable efforts have been focused on fluorinated organic co …

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Nov 2021 • The Journal of Physical Chemistry C

Asymmetric Spin Transport in Colloidal Quantum Dot Junctions

John P Philbin, Amikam Levy, Prineha Narang, Wenjie Dou

The study of charge and spin transport through semiconductor quantum dots is experiencing a renaissance due to recent advances in nanofabrication and the realization of quantum dots as candidates for quantum computing. In this work, we combine atomistic electronic structure calculations with quantum master equation methods to study the transport of electrons and holes through strongly confined quantum dots coupled to two leads with a voltage bias. We find that a competition between the energy spacing between the two lowest quasi-particle energy levels and the strength of the exchange interaction determines the spin states of the lowest two quasi-particle energy levels. Specifically, the low density of electron states results in a spin singlet being the lowest-energy two-electron state, whereas, in contrast, the high density of states and significant exchange interaction result in a spin triplet being the lowest …

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Nov 2021 • European Polymer Journal 142, 110145, 2021

Microspheres of biomolecules/macromolecules for enantioseparation applications

Amruta Mutalikdesai, Sudhakar Pagidi, Alfred Hassner, Aharon Gedanken

This review summarizes the recent advances in the enantioselective separation of small molecules using biomolecules/macromolecules built up by natural inherent chiral moieties. Although different kinds of chiral selectors are known to date, the microspheres based on biomolecules have received paramount importance in view of their green synthesis, selective and sensitive separation of enantiomers from the racemic mixture. Direct separation of enantiomers devoid of using high-performance liquid chromatography adds to the elegance of this approach. We have covered the preparation of various biomolecules spheres by different methods. The enantiomeric separation of amino acids, drugs and other racemates and the underlying plausible mechanism is discussed.

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Nov 2021 • Nature Physics

Imaging phonon-mediated hydrodynamic flow in WTe2

Uri Vool, Assaf Hamo, Georgios Varnavides, Yaxian Wang, Tony X Zhou, Nitesh Kumar, Yuliya Dovzhenko, Ziwei Qiu, Christina AC Garcia, Andrew T Pierce, Johannes Gooth, Polina Anikeeva, Claudia Felser, Prineha Narang, Amir Yacoby

In the presence of interactions, electrons in condensed-matter systems can behave hydrodynamically, exhibiting phenomena associated with classical fluids, such as vortices and Poiseuille flow–. In most conductors, electron–electron interactions are minimized by screening effects, hindering the search for hydrodynamic materials; however, recently, a class of semimetals has been reported to exhibit prominent interactions,. Here we study the current flow in the layered semimetal tungsten ditelluride by imaging the local magnetic field using a nitrogen-vacancy defect in a diamond. We image the spatial current profile within three-dimensional tungsten ditelluride and find that it exhibits non-uniform current density, indicating hydrodynamic flow. Our temperature-resolved current profile measurements reveal a non-monotonic temperature dependence, with the strongest hydrodynamic effects at approximately 20 K. We …

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Nov 2021 • International Journal of Molecular Sciences

Latently KSHV-infected cells promote further establishment of latency upon superinfection with KSHV

Chen Gam ze Letova, Inna Kalt, Meir Shamay, Ronit Sarid

Kaposi’s sarcoma-associated herpesvirus (KSHV) is a cancer-related virus which engages in two forms of infection: latent and lytic. Latent infection allows the virus to establish long-term persistent infection, whereas the lytic cycle is needed for the maintenance of the viral reservoir and for virus spread. By using recombinant KSHV viruses encoding mNeonGreen and mCherry fluorescent proteins, we show that various cell types that are latently-infected with KSHV can be superinfected, and that the new incoming viruses establish latent infection. Moreover, we show that latency establishment is enhanced in superinfected cells compared to primary infected ones. Further analysis revealed that cells that ectopically express the major latency protein of KSHV, LANA-1, prior to and during infection exhibit enhanced establishment of latency, but not cells expressing LANA-1 fragments. This observation supports the notion that the expression level of LANA-1 following infection determines the efficiency of latency establishment and avoids loss of viral genomes. These findings imply that a host can be infected with more than a single viral genome and that superinfection may support the maintenance of long-term latency.

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Nov 2021 • ACS Sustainable Chemistry & Engineering

Phase-dependent photocatalytic activity of bulk and exfoliated defect-controlled flakes of layered copper sulfides under simulated solar light

Madina Telkhozhayeva, Rajashree Konar, Ronit Lavi, Eti Teblum, Bibhudatta Malik, Sharon Ruthstein, Elisa Moretti, Gilbert Daniel Nessim

Sunlight-driven photocatalysis is an environmentally friendly approach to solve ecological issues. The development of simple yet sufficiently stable photocatalytic materials capable of responding to the full-spectrum light remains challenging. Here, we demonstrate the phase transformations of bulk copper sulfides from digenite (Cu9S5) to djurleite (Cu1.97S) and low chalcocite (Cu2S) by the reactive thermal annealing during ambient pressure chemical vapor deposition, followed by their top-down exfoliation. Using multiple techniques, we confirm that monoclinic Cu2S is primarily formed at higher temperatures or greater reaction times and using a reducing atmosphere. We measured the average thickness to be approximately 4 nm for the exfoliated flakes with relatively large lateral sizes of up to 10 μm. We tested the three phases of bulk copper sulfides and their exfoliated forms as photocatalysts for dye degradation …

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Nov 2021 • ACS Applied Nano Materials

Polydopamine Nanoparticles Containing a Cisplatin Analog for Anticancer Treatment and Diagnostics

Gil Yeroslavsky, Michal Richman, Asaf Gertler, Haim Y Cohen, Menachem Motiei, Rachela Popovtzer, Hugo E Gottlieb, Shai Rahimipour

Cancer is a leading cause of death with rates expected to grow with life expectancy. Among leading treatments, cisplatin, widely used to combat cancer, suffers from low stability and selectivity. Here, we covalently conjugated an analog of cisplatin to biocompatible polydopamine nanoparticles (PDA-NPs) to increase both properties. Dynamic light scattering and electron microscopy studies suggest that the platinum-conjugated PDA particles (Pt–PDA-NPs) are monodispersed and spherical with a diameter of about 200 nm with platinum atoms mostly in the shell. Particles were also characterized with inductively coupled plasma mass atomic emission spectroscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy to determine the localization and amount of Pt atoms. The chelated metal did not leach from the conjugated particles under normal physiological conditions, while it was released …

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Nov 2021 • Photochemical & Photobiological Sciences

Fluorophore spectroscopy in aqueous glycerol solution: the interactions of glycerol with the fluorophore

Haim Feldman, Mark A Iron, Dror Fixler, Sergei Moshkov, Naomi Zurgil, Elena Afrimzon, Mordechai Deutsch

A common perception exists that glycerol provides an inert-like environment modifying viscosity and index of refraction by its various concentrations in aqueous solution. Said perception is herein challenged by investigating the effects of the glycerol environment on the spectroscopic properties of fluorescein, as a representative fluorophore, using steady-state and time-resolved techniques and computational chemistry. Results strongly suggest that the fluorescence quantum yield, measured fluorescence lifetime (FLT), natural lifetime and calculated fluorescence lifetime are all highly sensitive to the presence of glycerol. Glycerol was found to impact both the ground and first excited states of fluorescein, quenching and modifying both absorption and emission spectra, affecting the fundamental electrical dipoles of the ground and first excited singlet states, and lowering FLT and quantum yield. Furthermore, the …

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Nov 2021 • ACS Applied Materials & Interfaces

Evaluation of Mg[B(HFIP)4]2-Based Electrolyte Solutions for Rechargeable Mg Batteries

Ben Dlugatch, Meera Mohankumar, Ran Attias, Balasubramoniam Murali Krishna, Yuval Elias, Yosef Gofer, David Zitoun, Doron Aurbach

Nov 2021 • Mbio

The Spliced Leader RNA Silencing (SLS) Pathway in Trypanosoma brucei Is Induced by Perturbations of Endoplasmic Reticulum, Golgi Complex, or Mitochondrial Protein Factors …

Uthman Okalang, Bar Mualem Bar-Ner, K Shanmugha Rajan, Nehemya Friedman, Saurav Aryal, Katarina Egarmina, Ronen Hope, Netaly Khazanov, Hanoch Senderowitz, Assaf Alon, Deborah Fass, Shulamit Michaeli

In the parasite Trypanosoma brucei, the causative agent of human African sleeping sickness, all mRNAs are trans-spliced to generate a common 5′ exon derived from the spliced leader (SL) RNA. Perturbations of protein translocation across the endoplasmic reticulum (ER) induce the spliced leader RNA silencing (SLS) pathway. SLS activation is mediated by a serine-threonine kinase, PK3, which translocates from the cytosolic face of the ER to the nucleus, where it phosphorylates the TATA-binding protein TRF4, leading to the shutoff of SL RNA transcription, followed by induction of programmed cell death. Here, we demonstrate that SLS is also induced by depletion of the essential ER-resident chaperones BiP and calreticulin, ER oxidoreductin 1 (ERO1), and the Golgi complex-localized quiescin sulfhydryl oxidase (QSOX). Most strikingly, silencing of Rhomboid-like 1 (TIMRHOM1), involved in mitochondrial …

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Nov 2021 • arXiv preprint arXiv:2111.12078

Spatial symmetry breaking by non-local Kerr-lensing in mode-locked lasers

Idan Parshani, Leon Bello, Mallachi-Elia Meller, Avi Pe'er

Kerr-lens mode-locking (KLM) is the work-horse mechanism for generation of ultrashort pulses, where a non-linear lens forms an effective ultrafast saturable absorber within the laser cavity. According to standard theory, the pulse in the cavity is a soliton, with a temporal profile and power determined by the non-linearity to exactly counteract diffraction and dispersion, resulting in pulses, whose power and shape are fixed across a wide range of pump powers. We show numerically and demonstrate experimentally that the non-local effect of the Kerr lens in a linear cavity allows the laser to deviate from the soliton model by breaking the spatial symmetry in the cavity between the forward and backward halves of the round-trip, and hence to extract more power in a single pulse, while maintaining stable cavity propagation. We confirm this prediction experimentally in a mode-locked Ti:Sapphire laser with a quantitative agreement to the simulation results. Our numerical tool opens new avenues to optimization and enhancement of the mode-locking performance based on direct examination of the Kerr medium and the spatio-temporal dynamics within it, which is difficult (or even impossible) to observe experimentally.

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Nov 2021 • ChemSusChem

Cover feature: AZ31 magnesium alloy foils as thin anodes for rechargeable magnesium batteries (ChemSusChem 21/2021)

Ananya Maddegalla, Ayan Mukherjee, J Alberto Blázquez, Eneko Azaceta, Olatz Leonet, Aroa R Mainar, Aleksey Kovalevsky, Daniel Sharon, Jean‐Frédéric Martin, Dane Sotta, Yair Ein‐Eli, Doron Aurbach, Malachi Noked

The Cover Feature shows the electrochemical performance of 25 μm AZ31 alloy as anode, in a full magnesium cell with Chevrel phase as cathode, in 0.25 m APC as electrolyte. The use of low concentration of foreign elements in magnesium AZ31 alloy (Al 3%, Zn 1%), increases the mechanical strength and ductility along with resistance to corrosion and weldability, giving similar electrochemical performance compared to 100 μm pure Magnesium metal foil. More information can be found in the Full Paper by A. Maddegalla et al.

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Nov 2021 • Journal of The Electrochemical Society

Toward high performance all solid-state Na batteries: investigation of electrolytes comprising NaPF6, poly (ethylene oxide) and TiO2

Gayathri Peta, Shaul Bublil, Hadas Alon-Yehezkel, Ortal Breuer, Yuval Elias, Nethanel Shpigel, Miryam Fayena-Greenstein, Diana Golodnitsky, Doron Aurbach

Solid electrolytes based on polyethylene oxide (PEO) have been studied for decades, owing to their facile and low-cost processing, good electrochemical stability, and excellent complexation with alkali metal salts. Complexes of PEO with appropriate sodium salts are well known for ionic conduction. Here, pristine NaPF 6: P (EO) 16 and a composite solid electrolyte containing TiO 2 nanowires were investigated as candidates for rechargeable solid-state sodium batteries. Comprehensive electrochemical characterizations were carried out, including ionic conductivity, transference number, and structural stability. At elevated temperatures, the specific capacity of an all-solid-state Na 3 Ti 2 (PO 4) 3 (Na/NTP) sodium battery was 110 mAh g− 1, higher than room-temperature cells with liquid electrolyte solutions. We attribute this behavior to increased conductivity of the polymer electrolyte, induced by the ceramic …

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Nov 2021 • Energy Storage Materials

Boron doped Ni-rich LiNi0. 85Co0. 10Mn0. 05O2 cathode materials studied by structural analysis, solid state NMR, computational modeling, and electrochemical performance

Susai Francis Amalraj, Ravikumar Raman, Arup Chakraborty, Nicole Leifer, Raju Nanda, Sooraj Kunnikuruvan, Tatyana Kravchuk, Judith Grinblat, Vladimir Ezersky, Rong Sun, Francis Leonard Deepak, Christoph Erk, Xiaohan Wu, Sandipan Maiti, Hadar Sclar, Gil Goobes, Dan Thomas Major, Michael Talianker, Boris Markovsky, Doron Aurbach

This work is part of ongoing and systematic investigations by our groups on the synthesis, electrochemical behavior, structural investigations, and computational modeling of the Ni-rich materials Li[NixCoyMnz]O2 (x+y+z=1; x≥0.8) for advanced lithium-ion batteries. This study focuses on the LiNi0.85Co0.10Mn0.05O2 (NCM85) material and its improvement upon doping with B3+ cations. The data demonstrate the substantial improvement of the doped electrodes in terms of cycling performance, lower voltage hysteresis and reduced self-discharge upon high temperature storage. The electronic structure of the undoped and B-doped material was modelled using density functional theory (DFT), which identified interstitial positions as the preferential location of the dopant. DFT models were also used to shed light on the influence of boron on surface segregation, surface stability, and oxygen binding energy in NCM85 …

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Nov 2021 • Journal of the American Chemical Society

Tunable Cr4+ Molecular Color Centers

Daniel W Laorenza, Arailym Kairalapova, Sam L Bayliss, Tamar Goldzak, Samuel M Greene, Leah R Weiss, Pratiti Deb, Peter J Mintun, Kelsey A Collins, David D Awschalom, Timothy C Berkelbach, Danna E Freedman

The inherent atomistic precision of synthetic chemistry enables bottom-up structural control over quantum bits, or qubits, for quantum technologies. Tuning paramagnetic molecular qubits that feature optical-spin initialization and readout is a crucial step toward designing bespoke qubits for applications in quantum sensing, networking, and computing. Here, we demonstrate that the electronic structure that enables optical-spin initialization and readout for S = 1, Cr(aryl)4, where aryl = 2,4-dimethylphenyl (1), o-tolyl (2), and 2,3-dimethylphenyl (3), is readily translated into Cr(alkyl)4 compounds, where alkyl = 2,2,2-triphenylethyl (4), (trimethylsilyl)methyl (5), and cyclohexyl (6). The small ground state zero field splitting values (<5 GHz) for 1–6 allowed for coherent spin manipulation at X-band microwave frequency, enabling temperature-, concentration-, and orientation-dependent investigations of the spin dynamics …

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Nov 2021 • Materials Today

Combinatorial growth of multinary nanostructured thin functional films

Hannah-Noa Barad, Mariana Alarcón-Correa, Gerardo Salinas, Eran Oren, Florian Peter, Alexander Kuhn, Peer Fischer

The rapid generation of material libraries with multidimensional gradients is important for the discovery of new functional materials. Here we report an integrated fabrication scheme, based on glancing angle physical vapor deposition, to form a thin-film materials library with controlled variations in nanoshape, multinary composition, and oxidation state on a single large area substrate. We demonstrate the versatility of the method by growing an octonary materials system, which we characterize with high-throughput methods, and reveal variations in several physico-chemical properties. Among others, we examine the materials library in the frame of the oxygen evolution reaction and show that nanostructuring leads to NiO clusters that are active towards such a reaction. Our scheme can be readily extended to include more starting elements, and can be transferred to other deposition methods, making this an adaptable …

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Nov 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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Nov 2021 • JOSA B

Light detection and ranging (lidar): introduction

Zeev Zalevsky, Gerald S Buller, Tao Chen, Moshik Cohen, Rory Barton-Grimley

In this introduction we provide an overview of the papers that were accepted for publication in the special issue on light detection and ranging (lidar). Four of the papers were published in JOSA A, and four were published in JOSA B. They represent different aspects of this important and fast-growing field while showing the relevant state-of-the-art achievements currently existing in the field of lidars in the world of science and engineering.

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Nov 2021 • Journal of The Electrochemical Society

In situ stress measurements on thin film Au positive electrode during the first discharge of Li-O2 batteries

Hannah Dykes, Daniel Sharon, Malachi Noked, Özgür Çapraz

The formation and growth of the Li 2 O 2 discharge product impacts the reversibility of the oxygen evolution and reduction reactions in Li-O 2 batteries which may lead to a shorter cycle life. A clear understanding of the surface reactions and the growth mechanism of Li 2 O 2 requires probing dynamic changes on the surface of the positive electrodes in situ during the discharge of a Li-O 2 battery. To investigate this, we establish an experimental system by adopting a multi-beam optical sensor (MOS) and developing a custom-made battery cell. First, the accuracy and reliability of the system was demonstrated by analyzing the stress accumulation on the Au negative electrode during Li plating/stripping, and the results were consistent with an earlier single-beam scanning deflectometry report. Then, the Li-O 2 battery was discharged in LiNO 3 in diglyme electrolyte by applying either linear sweep voltammetry or by …

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Nov 2021 • Microscopy Research and Technique

A simple, inexpensive and multi‐scale 3‐D fluorescent test sample for optical sectioning microscopies

Ilya Olevsko, Kaitlin Szederkenyi, Jennifer Corridon, Aaron Au, Brigitte Delhomme, Thierry Bastien, Julien Fernandes, Christopher Yip, Martin Oheim, Adi Salomon

Fluorescence standards allow for quality control and for the comparison of data sets across instruments and laboratories in applications of quantitative fluorescence. For example, users of microscopy core facilities can expect a homogenous and time‐invariant illumination and an uniform detection sensitivity, which are prerequisites for imaging analysis, tracking or fluorimetric pH or Ca2+‐concentration measurements. Similarly, confirming the three‐dimensional (3‐D) resolution of optical sectioning microscopes calls for a regular calibration with a standardized point source. The test samples required for such measurements are typically different ones, they are often expensive and they depend much on the very microscope technique used. Similarly, the ever‐increasing choice among microscope techniques and geometries increases the demand for comparison across instruments. Here, we advocate and …

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