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Jan 2022 • Laser & Photonics Reviews

Interpolarization Forward Stimulated Brillouin Scattering in Standard Single‐Mode Fibers

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

Forward stimulated Brillouin scattering in standard single‐mode fibers draws increasing interest toward sensing and signal processing applications. The process takes place through two classes of guided acoustic modes: purely radial ones and torsional‐radial modes with twofold azimuthal symmetry. The latter case cannot be described in terms of scalar models alone. In this work, the polarization attributes of forward stimulated Brillouin scattering in single‐mode fibers are investigated in analysis and experiment. Torsional‐radial acoustic modes are stimulated by orthogonally polarized pump tones, a first such report in standard single‐mode fibers. The scattering of optical probe waves by torsional‐radial modes may take up the form of phase modulation, cross‐polarization coupling, or a combination of both, depending on polarization. Lastly, this analysis predicts that circular and orthogonal pump tones may …

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Jan 2022 • ACS Applied Materials & Interfaces

Chemical vapor deposition of spherical amorphous selenium Mie resonators for infrared meta-optics

Danveer Singh, Michal Poplinger, Avraham Twitto, Rafi Snitkoff, Pilkhaz Nanikashvili, Ori Azolay, Adi Levi, Chen Stern, Gili Cohen Taguri, Asaf Albo, Doron Naveh, Tomer Lewi

Jan 2022 • Photonics

Signal-to-Noise Ratio Improvement for Multiple-Pinhole Imaging Using Supervised Encoder–Decoder Convolutional Neural Network Architecture

Eliezer Danan, Nadav Shabairou, Yossef Danan, Zeev Zalevsky

Digital image devices have been widely applied in many fields, such as individual recognition and remote sensing. The captured image is a degraded image from the latent observation, where the degradation processing is affected by some factors, such as lighting and noise corruption. Specifically, noise is generated in the processing of transmission and compression from the unknown latent observation. Thus, it is essential to use image denoising techniques to remove noise and recover the latent observation from the given degraded image. In this research, a supervised encoder–decoder convolution neural network was used to fix image distortion stemming from the limited accuracy of inverse filter methods (Wiener filter, Lucy–Richardson deconvolution, etc.). Particularly, we will correct image degradation that mainly stems from duplications arising from multiple-pinhole array imaging.

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Jan 2022 • Journal of The Electrochemical Society

An Improved Cycling Performance of Different Types of Composite Sulfur-Carbon Cathodes with the Use of Lithium Polysulfides Containing Electrolyte Solutions

E Markevich, G Salitra, H Yoshida, S Sawada, D Aurbach

We report on stabilization of Li–S cells with different types of composite sulfur cathodes using ethereal LiTFSI/LiNO 3/DOL/DME electrolyte solutions containing a-priori 0.1 M Li 2 S 8. These electrolyte solutions enable an improved cycling behavior for Li–S cells compared to Li 2 S 8-free electrolyte solutions, thanks to the presence of LiS x species from the beginning of operation. We show that Li anodes cycled in Li∣ S cells with solutions containing Li 2 S 8 possess flatter and more uniform surface, higher dimensions of the surface structures in average and, as a result, a lower surface area. This surface morphology ensures a low rate of parasitic surface reactions of the electrolyte components on the Li anodes' surface, slower depletion of the electrolyte solution in the cells and stabilization of the cells cycling. Besides, the presence of Li 2 S 8 maintains a better integrity of composite sulfur/carbon/PVdF cathodes …

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Jan 2022 • ACS Applied Nano Materials

Acoustic Green Synthesis of Graphene-Gallium Nanoparticles and PEDOT: PSS Hybrid Coating for Textile To Mitigate Electromagnetic Radiation Pollution

Poushali Das, Sayan Ganguly, Ilana Perelshtein, Shlomo Margel, Aharon Gedanken

Solid matrix-supported liquid metal nanoparticles have been drawing attention as a nanoadditive in the fabrication of electroconductive flexible and soft materials. The present work reports a facile, green, and sonochemical synthesis approach of gallium (Ga) nanoparticles embedded in reduced graphene oxide (RGO) under ambient conditions for the first time. The as-synthesized ultrasonic energy-irradiated RGO/Ga nanocomposite was studied using SEM, TEM, DSC, XRD, XPS, and solid-state NMR. Because of their electrical conductivity, RGO/Ga nanoparticles have been used as a conducting inclusion for a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) matrix and coated on cotton fabrics to develop a smart e-textile for electromagnetic (EM) radiation-shielding application. In the X-band (8.2–12.4 GHz) frequency range, the nanocomposites’ EM interference-shielding efficiency was about …

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Jan 2022 • Scientific Reports

Picosecond pulsed laser illumination: an ultimate solution for photonic versus thermal processes’ contest in SOI photo-activated modulator

David Glukhov, Zeev Zalevsky, Avi Karsenty

The functionality of a nanoscale silicon-based optoelectronic modulator is deeply analyzed while it appears that two competing processes, thermal and photonic, are occurring at the same time, and are preventing the optimization of the electro-optics coupling. While an incident illumination-beam first process is translated into photons, generating pairs of electrons–holes, a second process of thermal generation, creating phonons enables a loss of energy. Complementary studies, combining strong analytical models and numerical simulations, enabled to better understand this competition between photonic and thermal activities, in order to optimize the modulator. Moreover, in order to prevent unnecessary heating effects and to present a proposed solution, a picosecond pulsed laser is suggested and demonstrated as the ultimate solution so no energy will be wasted in heat, and still the photonic energy will be fully …

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Jan 2022 • arXiv preprint arXiv:2201.09386

Impact of Non-Hermiticity and Nonlinear Interactions on Disordered-Induced Localized Modes

Bhupesh Kumar, Patrick Sebbah

If disorder-induced Anderson localized states have been observed experimentally in optics, their study remains challenging leaving a number of open questions unsolved. Among them, the impact on Anderson localization of non-Hermiticity, optical gain and loss, and more generally, nonlinearities has been the subject of numerous theoretical debates, without yet any conclusive experimental demonstration. Indeed, in systems where localized modes have reasonable spatial extension to be observed and investigated, their mutual interaction and coupling to the sample boundaries make it extremely difficult to isolate them spectrally and investigate them alone. Recently, we successfully exhibited localized lasing modes individually in an active disordered medium, using pump-shaping optimization technique. However, a one-to-one identification of the lasing modes with the eigenmodes of the passive system was not possible, as the impact of non-Hermiticity and nonlinear gain on these localized states was unknown. Here, we apply the pump-shaping method to fully control the non-Hermiticity of an active scattering medium. Direct imaging of the light distribution within the random laser allows us to demonstrate unequivocally that the localized lasing modes are indeed the modes of the passive system. This opens the way to investigate the robustness of localized states in the presence of nonlinear gain and nonlinear modal interactions. We show that, surprisingly, gain saturation and mode competition for gain does not affect the spatial distribution of the modes.

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Jan 2022 • The CRISPR Journal

High-throughput imaging of CRISPR-and recombinant adeno-associated virus–induced DNA damage response in human hematopoietic stem and progenitor cells

Daniel Allen, Lucien E Weiss, Alon Saguy, Michael Rosenberg, Ortal Iancu, Omri Matalon, Ciaran Lee, Katia Beider, Arnon Nagler, Yoav Shechtman, Ayal Hendel

CRISPR-Cas technology has revolutionized gene editing, but concerns remain due to its propensity for off-target interactions. This, combined with genotoxicity related to both CRISPR-Cas9-induced double-strand breaks and transgene delivery, poses a significant liability for clinical genome-editing applications. Current best practice is to optimize genome-editing parameters in preclinical studies. However, quantitative tools that measure off-target interactions and genotoxicity are costly and time-consuming, limiting the practicality of screening large numbers of potential genome-editing reagents and conditions. Here, we show that flow-based imaging facilitates DNA damage characterization of hundreds of human hematopoietic stem and progenitor cells per minute after treatment with CRISPR-Cas9 and recombinant adeno-associated virus serotype 6. With our web-based platform that leverages deep learning for …

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Jan 2022 • Optics Express

Single-shot analysis of amplified correlated light

Sara Meir, Avi Klein, Hamootal Duadi, Eliahu Cohen, Moti Fridman

Correlated beams are important in classical and quantum communication as well as other technologies. However, classical amplifiers, which are essential for long transmission of correlated beams, degrade the correlation due to noise and due to the amplifier spectral response. We measure, with a novel high resolution single-shot measurement system, the impact of amplifiers on correlated beams. We develop a new method for analyzing the correlation between the signal and idler beams by choosing peaks in the pulses according to their power levels. We demonstrate how to tailor the correlation after the amplifier to obtain either higher or lower correlation. Our research may influence the future use of amplifiers in non-classical communication systems as well as the transmission of quantum information over long distances.

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Jan 2022 • ACS Catalysis

Recent progress and viability of PGM-free catalysts for hydrogen evolution reaction and hydrogen oxidation reaction

Wenjamin Moschkowitsch, Oran Lori, Lior Elbaz

The global energy demand is expected to rise continuously in the foreseeable future, and this demand cannot be fulfilled with fossil fuels if the ambitious goals for global reduction in greenhouse gas emissions are to be met. 1, 2 Therefore, it is necessary to switch to energy production from sustainable energy sources such as solar and wind. 3, 4 These sources suffer from intermittent production, producing a surplus of energy at certain hours and seasons and little to none at others. Hence, large energy storage solutions are necessary in order to store the excess energy in peak times and compensate at the lowand down-times. 4, 5One of the most promising energy storage solutions today is chemical, in the form of hydrogen, which can be used with fuel cells to generate electricity or burned to generate heat, as well as being used in the chemical industry for various applications. 5 It can be easily produced with various …

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Jan 2022 • ACS sensors

Rapid Biosensing Method for Detecting Protein–DNA Interactions

Shira Roth, Diana Ideses, Tamar Juven-Gershon, Amos Danielli

Identifying and investigating protein–DNA interactions, which play significant roles in many biological processes, is essential for basic and clinical research. Current techniques for identification of protein–DNA interactions are laborious, time-consuming, and suffer from nonspecific binding and limited sensitivity. To overcome these challenges and assess protein–DNA interactions, we use a magnetic modulation biosensing (MMB) system. In MMB, one of the interacting elements (protein or DNA) is immobilized to magnetic beads, and the other is coupled to a fluorescent molecule. Thus, the link between the magnetic bead and the fluorescent molecule is established only when binding occurs, enabling detection of the protein–DNA interaction. Using magnetic forces, the beads are concentrated and manipulated in a periodic motion in and out of a laser beam, producing a detectable oscillating signal. Using MMB, we …

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Jan 2022 • ACS Photonics

Tunable metasurface using thin-film lithium niobate in the telecom regime

Aharon Weiss, Christian Frydendahl, Jonathan Bar-David, Roy Zektzer, Eitan Edrei, Jacob Engelberg, Noa Mazurski, Boris Desiatov, Uriel Levy

Jan 2022 • Optica

Chemical element mapping by x-ray computational ghost fluorescence

Yishay Klein, Or Sefi, Hila Schwartz, Sharon Shwartz

Chemical element mapping is an imaging tool that provides essential information about composite materials, and it is crucial for a broad range of fields ranging from fundamental science to numerous applications. Methods that exploit x-ray fluorescence are very advantageous and are widely used, but require focusing of the input beam and raster scanning of the sample. Thus, the methods are slow and exhibit limited resolution due to focusing challenges. Here, we demonstrate an x-ray fluorescence method based on computational ghost imaging that overcomes those limitations since it does not require focusing and show that when it is combined with compressed sensing the total measurement time can be significantly reduced. Our method opens the possibility to significantly enhance the resolution of chemical element maps and to extend the applicability of x-ray fluorescence inspection to new fields where the …

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Jan 2022 • Handbook of Biofuels, 621-642, 2022

Solar intervention in bioenergy

Indra Neel Pulidindi, Aharon Gedanken

Research interest in the integration of solar energy-harvesting technology with bioenergy production is growing at a remarkable pace. The time of fruition of a completely off-grid solar-powered refinery facility is not too far, at least in the specific instance of bioenergy sources, namely, biodiesel and bioethanol. Electricity generated from solar panels is used for the cultivation of microalgae in outdoor open ponds. The solar thermal energy is converted into electricity by solar panels, and the electricity is stored in lead-acid batteries that are used to power the motors to rotate the agitator blades for stirring the contents of the algal culture. The biomass productivity of outdoor open ponds completely powered by solar energy (5.8 gm2/d of Nannochloropsis oceanica SCS-1981) is on par with the traditional raceway ponds. Such innovation in harvesting microalgae has led to energy savings and cost reduction. A solar energy …

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Jan 2022 • Scientific Reports

Remote photonic detection of human senses using secondary speckle patterns

Zeev Kalyuzhner, Sergey Agdarov, Itai Orr, Yafim Beiderman, Aviya Bennett, Zeev Zalevsky

Neural activity research has recently gained significant attention due to its association with sensory information and behavior control. However, the current methods of brain activity sensing require expensive equipment and physical contact with the tested subject. We propose a novel photonic-based method for remote detection of human senses. Physiological processes associated with hemodynamic activity due to activation of the cerebral cortex affected by different senses have been detected by remote monitoring of nano‐vibrations generated by the transient blood flow to the specific regions of the human brain. We have found that a combination of defocused, self‐interference random speckle patterns with a spatiotemporal analysis, using Deep Neural Network, allows associating between the activated sense and the seemingly random speckle patterns.

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Jan 2022 • bioRxiv

T cell receptor beta germline variability is revealed by inference from repertoire data

Aviv Omer, Ayelet Peres, Oscar L Rodrigues, Corey T Watson, William Lees, Pazit Polak, Andrew M Collins, Gur Yaari

T and B cell repertoires constitute the foundation of adaptive immunity. Adaptive immune receptor repertoire sequencing (AIRR-seq) is a common approach to study immune system dynamics. Understanding the genetic factors influencing the composition and dynamics of these repertoires is of major scientific and clinical importance. The chromosomal loci encoding for the variable regions of T and B cell receptors (TCRs and BCRs, respectively) are challenging to decipher due to repetitive elements and undocumented structural variants. To confront this challenge, AIRR-seq-based methods have been developed recently for B cells, enabling genotype and haplotype inference and discovery of undocumented alleles. Applying these methods to AIRR-seq data reveals a plethora of undocumented genomic variations. However, this approach relies on complete coverage of the receptors9 variable regions, and most T cell studies sequence only a small fraction of the variable region. Here, we adapted BCR inference methods to full and partial TCR sequences, and identified 38 undocumented polymorphisms in TRBV, 15 of them were also observed in genomic data assemblies. Further, we identified 31 undocumented 59 UTR sequences. A subset of these inferences was also observed using independent genomic approaches. We found the two documented TRBD2 alleles to be equally abundant in the population, and show that the single nucleotide that differentiates them is strongly associated with dramatic changes in the expressed repertoire. Our findings expand the knowledge of genomic variation in the TRB (T Cell Receptor Beta) locus and …

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Jan 2022 • The Journal of Chemical Physics

Gas of sub-recoiled laser cooled atoms described by infinite ergodic theory

Eli Barkai, Günter Radons, Takuma Akimoto

It is well known that for sub-recoiled laser cooled atoms L\'evy statistics and deviations from usual ergodic behaviour come into play.Here we show how tools from infinite ergodic theory describe the cool gas.Specifically, we derive the scaling function and the infinite invariant density of a stochastic model for the momentum of the atoms using two approaches.The first is a direct analysis of the master equation and the second following the analysis of Bertin and Bardou using the lifetime dynamics. The two methods are shown to be identical, but yield different insights into the problem. In the main part of the paper we focus on the case where the laser trapping is strong, namely the rate of escape from the velocity trap is for and .We construct a machinery to investigate the time averages of physical observables and their relationt o ensemble averages. The time averages are given in terms of functionals of the …

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Jan 2022 • Advanced Materials Interfaces

Growth of hybrid chiral thin films by molecular layer deposition zinc/cysteine as a case study

Reut Yemini, Shalev Blanga, Hagit Aviv, Ilana Perelshtein, Eti Teblum, Shahar Dery, Elad Gross, Yitzhak Mastai, Malachi Noked, Ortal Lidor‐Shalev

Jan 2022 • bioRxiv

Lytic reactivation of the Kaposi’s sarcoma-associated herpesvirus (KSHV) is accompanied by major nucleolar alterations

Nofar Atari, K Shanmugha Rajan, Vaibhav Chikne, Smadar Cohen-Chalamish, Odelia Orbaum, Avi Jacob, Inna Kalt, Shulamit Michaeli, Ronit Sarid

The nucleolus is a sub-nuclear compartment whose primary function is the biogenesis of ribosomal subunits. Certain viral infections affect the morphology and composition of the nucleolar compartment and influence ribosomal RNA (rRNA) transcription and maturation. However, no description of nucleolar morphology and function during infection with Kaposi’s sarcoma-associated herpesvirus (KSHV) is available to date. Using immunofluorescence microscopy, we documented extensive destruction of the nuclear and nucleolar architecture during lytic reactivation of KSHV. This was manifested by redistribution of key nucleolar proteins, including the rRNA transcription factor, UBF, the essential pre-rRNA processing factor Fibrillarin, and the nucleolar multifunctional phosphoproteins Nucleophosmin (NPM1) and Nucleolin. Distinct delocalization patterns were evident; certain nucleolar proteins remained together whereas others dissociated, implying that nucleolar proteins undergo nonrandom programmed dispersion. Of note, neither Fibrillarin nor UBF colocalized with promyelocytic leukemia (PML) nuclear bodies or with the viral protein LANA-1, and their redistribution was not dependent on viral DNA replication or late viral gene expression. No significant changes in pre-rRNA levels and no accumulation of pre-rRNA intermediates were found by RT-qPCR and Northern blot analysis, respectively. Furthermore, fluorescent in situ hybridization (FISH), combined with immunofluorescence, revealed an overlap between Fibrillarin and internal transcribed spacer 1 (ITS1), which represents the primary product of the pre-rRNA, suggesting that the …

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Jan 2022 • Nanomaterials 12 (6), 898, 2022

Synthesis of Doped/Hybrid Carbon Dots and Their Biomedical Application

Vijay Bhooshan Kumar, Ze’ev Porat, Aharon Gedanken

Carbon dots (CDs) are a novel type of carbon-based nanomaterial that has gained considerable attention for their unique optical properties, including tunable fluorescence, stability against photobleaching and photoblinking, and strong fluorescence, which is attributed to a large number of organic functional groups (amino groups, hydroxyl, ketonic, ester, and carboxyl groups, etc.). In addition, they also demonstrate high stability and electron mobility. This article reviews the topic of doped CDs with organic and inorganic atoms and molecules. Such doping leads to their functionalization to obtain desired physical and chemical properties for biomedical applications. We have mainly highlighted modification techniques, including doping, polymer capping, surface functionalization, nanocomposite and core-shell structures, which are aimed at their applications to the biomedical field, such as bioimaging, bio-sensor applications, neuron tissue engineering, drug delivery and cancer therapy. Finally, we discuss the key challenges to be addressed, the future directions of research, and the possibilities of a complete hybrid format of CD-based materials. View Full-Text

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Jan 2022 • bioRxiv

In vitro and in vivo NIR Fluorescence Lifetime Imaging with a time-gated SPAD camera

Jason T Smith, Alena Rudkouskaya, Shan Gao, Juhi M Gupta, Arin Ulku, Claudio Bruschini, Edoardo Charbon, Shimon Weiss, Margarida Barroso, Xavier Intes, Xavier Michalet

Near-infrared (NIR) fluorescence lifetime imaging (FLI) provides a unique contrast mechanism to monitor biological parameters and molecular events in vivo. Single-photon avalanche photodiode (SPAD) cameras have been recently demonstrated in FLI microscopy (FLIM) applications, but their suitability for in vivo macroscopic FLI (MFLI) in deep tissues remains to be demonstrated. Herein, we report in vivo NIR MFLI measurement with SwissSPAD2, a large time-gated SPAD camera. We first benchmark its performance in well-controlled in vitro experiments, ranging from monitoring environmental effects on fluorescence lifetime, to quantifying Förster Resonant Energy Transfer (FRET) between dyes. Next, we use it for in vivo studies of target-drug engagement in live and intact tumor xenografts using FRET. Information obtained with SwissSPAD2 was successfully compared to that obtained with a gated-ICCD camera, using two different approaches. Our results demonstrate that SPAD cameras offer a powerful technology for in vivo preclinical applications in the NIR window.

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