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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

Metasurfaces have seen a great evolution over the last few years, demonstrating a high degree of control over the amplitude, phase, polarization, and spectral properties of reflected or transmitted electromagnetic waves. Nevertheless, the inherent limitation of static metasurface realizations, which cannot be controlled after their fabrication, engages an ongoing pursuit for reconfigurable metasurfaces with profound tunability. In this paper, we mitigate this grand challenge by demonstrating a new method for free-space rapid optical tunability and modulation, utilizing a planar aluminum nanodisk metasurface coated with indium tin oxide (ITO) on a thin film of lithium niobate (LiNbO) with a chromium/gold (Cr/Au) substrate. Resonance coupling gives rise to an enhanced, confined electromagnetic field residing in the thin film, leading to a narrow and high contrast dip in reflectance of around 1.55 μm. The precise spectral …

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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 • 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

An engineered nanocomplex with Photodynamic and Photothermal synergistic properties for cancer treatment

Eli Varon, Gaddi Blumrosen, Moshe Sinvani, Elina Haimov, Shlomi Polani, Michal Natan, Irit Shoval, Ayelet Atkins, David Zitoun, Orit Shefi

Photodynamic therapy (PDT) and photothermal therapy (PTT) are promising therapeutic methods for cancer treatment; however, as single modality therapies, either PDT or PTT are still limited in their success rate. A dual application of both PDT and PTT, in a combined protocol, has gained immense interest. In this study, gold nanoparticles (AuNPs) are conjugated with a PDT agent, meso-tetrahydroxyphenylchlorin (mTHPC) photosensitizer, designed as nanotherapeutic agents that can activate a dual photodynamic/photothermal therapy. The AuNP-mTHPC complex is biocompatible, soluable, and photostable. PDT efficiency is high because of immediate reactive oxygen species (ROS) production upon mTHPC activation by the 650 nm laser which decreased mitochondrial membrane potential (∆ψm). Likewise, the AuNP-mTHPC complex is used as a photoabsorbing (PTA) agent for PTT, due to efficient plasmon absorption and excellent photothermal conversion characteristics of AuNPs under laser irradiation at 532 nm. Under the laser irradiation of a PDT/PTT combination, a twofold phototoxicity outcome follows, compared to PDT-only or PTT-only treatment. This indicates that PDT and PTT have synergistic effects together as a combined therapeutic method. Hence, applying our AuNP-mTHPC may be a potential treatment of cancer in the biomedical field.

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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 • 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 • BMJ Open

External validation and recalibration of an incidental meningioma prognostic model - IMPACT: protocol for an international multicentre retrospective cohort study.

International Consortium on Meningioma (ICOM) and British Neurosurgical Trainee Research Collaborative (BNTRC) IMPACT Study Investigators

IntroductionDue to the increased use of CT and MRI, the prevalence of incidental findings on brain scans is increasing. Meningioma, the most common primary brain tumour, is a frequently encountered incidental finding, with an estimated prevalence of 3/1000. The management of incidental meningioma varies widely with active clinical-radiological monitoring being the most accepted method by clinicians. Duration of monitoring and time intervals for assessment, however, are not well defined. To this end, we have recently developed a statistical model of progression risk based on single-centre retrospective data. The model Incidental Meningioma: Prognostic Analysis Using Patient Comorbidity and MRI Tests (IMPACT) employs baseline clinical and imaging features to categorise the patient with an incidental meningioma into one of three risk groups: low, medium and high risk with a proposed active monitoring …

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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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2022 • Frontiers in Immunology

A BALB/c IGHV reference set, defined by haplotype analysis of long-read VDJ-c sequences from F1 (BALB/cx C57BL/6) mice

Katherine JL Jackson, Justin T Kos, William Lees, William S Gibson, Melissa Laird Smith, Ayelet Peres, Gur Yaari, Martin Corcoran, Christian E Busse, Mats Ohlin, Corey T Watson, Andrew M Collins

The immunoglobulin genes of inbred mouse strains that are commonly used in models of antibody-mediated human diseases are poorly characterized. This compromises data analysis. To infer the immunoglobulin genes of BALB/c mice, we used long-read SMRT sequencing to amplify VDJ-C sequences from F1 (BALB/cx C57BL/6) hybrid animals. Strain variations were identified in the Ighm and Ighg2b genes, and analysis of VDJ rearrangements led to the inference of 278 germline IGHV alleles. 169 alleles are not present in the C57BL/6 genome reference sequence. To establish a set of expressed BALB/c IGHV germline gene sequences, we computationally retrieved IGHV haplotypes from the IgM dataset. Haplotyping led to the confirmation of 162 BALB/c IGHV gene sequences. A musIGHV398 pseudogene variant also appears to be present in the BALB/cByJ substrain, while a functional musIGHV398 gene is …

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2022 • Nanoscale

NiFe-mixed metal porphyrin aerogels as oxygen evolution reaction catalysts in alkaline electrolysers

Wenjamin Moschkowitsch, Bipasa Samanta, Noam Zion, Hilah C Honig, David A Cullen, Maytal Caspary Toroker, Lior Elbaz

Aerogels are a very interesting group of materials owing to their unique physical and chemical properties. In the context of electrocatalysis, the focus has been on their physical properties, and they have been used primarily as catalyst supports so far. In this work, we synthesized porphyrin aerogels containing Ni and NiFe mixed metal materials and studied them as catalysts for the oxygen evolution reaction (OER). Different Ni : Fe ratios were synthesized and studied in electrochemical cells, and DFT calculations were conducted in order to gain insight into their behavior. The activity trends were dependent on the metal ratios and differ from known NiFeOOH materials due to the change in the oxidation states of the metals to higher numbers. Herein, we show that Ni and Fe have a synergistic effect on the OER, despite being structurally separated. They are connected electronically, though, through a large organic …

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2022 • QRB Discovery

The conformational plasticity of the selectivity filter methionines controls the in-cell Cu (I) uptake through the CTR1 transporter

Pavel Janoš, Jana Aupič, Sharon Ruthstein, Alessandra Magistrato

Copper is a trace element vital to many cellular functions. Yet its abnormal levels are toxic to cells, provoking a variety of severe diseases. The high affinity copper transporter 1 (CTR1), being the main in-cell copper [Cu(I)] entry route, tightly regulates its cellular uptake via a still elusive mechanism. Here, all-atoms simulations unlock the molecular terms of Cu(I) transport in eukaryotes disclosing that the two methionine (Met) triads, forming the selectivity filter, play an unprecedented dual role both enabling selective Cu(I) transport and regulating its uptake rate thanks to an intimate coupling between the conformational plasticity of their bulky side chains and the number of bound Cu(I) ions. Namely, the Met residues act as a gate reducing the Cu(I) import rate when two ions simultaneously bind to CTR1. This may represent an elegant autoregulatory mechanism through which CTR1 protects the cells from excessively …

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2022 • Micro-and Nano-containers for Smart Applications, 127-153, 2022

Containers for drug delivery

Sayan Ganguly, Poushali Das, Shlomo Margel

Precise delivery of therapeutic cargos to the destined location is a medical demand for desirable physiological responses. In this discussion the synthetic approaches to prepare cargos and their mode of delivery have been addressed. The versatile synthesis and materialistic approaches have revealed by various scientists that besides carrying drugs/biomolecules the protection is also needed. The merits and demerits of those various architectural units also have been discussed in brief to assess their acceptability and mode of usages.

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2022 • Advanced Functional Materials

Bioengineering 3D Neural Networks Using Magnetic Manipulations

Reut Plen, Alejandra Smith, Ofir Blum, Or Aloni, Uri Locker, Zehavit Shapira, Shlomo Margel, Orit Shefi

Controlling nerve cells to form pre‐designed 3D neural networks that recapitulate the intricate neural interconnectivity in the brain is essential for developing neuronal interfaces and new regeneration approaches. Here, nerve cells within 3D biomaterials are dynamically localized using nano‐based magnetic manipulations. Nerve cells are transformed into magnetic units and their organizational layout is manipulated using external magnetic field gradients. Iron oxide nanoparticles are incorporated into both Pheochromocytoma cell‐line 12 (PC12) cells and primary mice cortical neurons and the magnetized cells are subjected to multiple magnetic fields using pre‐designed magnetic arrays. Their movement is controlled inside multi‐layered 3D collagen scaffolds, which simulate the innate properties of in‐vivo tissue structures. Via these magnetic manipulations, functional 3D microarchitectures of neural networks are …

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2022 • Chemical science

Cu (II)-based DNA labeling identifies the structural link between transcriptional activation and termination in a metalloregulator

Joshua Casto, Alysia Mandato, Lukas Hofmann, Idan Yakobov, Shreya Ghosh, Sharon Ruthstein, Sunil Saxena

Understanding the structural and mechanistic details of protein-DNA interactions that lead to cellular defence against toxic metal ions in pathogenic bacteria can lead to new ways of combating their virulence. Herein, we examine the Copper Efflux Regulator (CueR) protein, a transcription factor which interacts with DNA to generate proteins that ameliorate excess free Cu(I). We exploit site directed Cu(II) labeling to measure the conformational changes in DNA as a function of protein and Cu(I) concentration. Unexpectedly, the EPR data indicate that the protein can bend the DNA at high protein concentrations even in the Cu(I)-free state. On the other hand, the bent state of the DNA is accessed at a low protein concentration in the presence of Cu(I). Such bending enables the coordination of the DNA with RNA polymerase. Taken together, the results lead to a structural understanding of how transcription is activated in …

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2022 • Physical Chemistry Chemical Physics

The effects of thermal treatment and irradiation on the chemical properties of natural diamonds

Ira Litvak, Avner Cahana, Yaakov Anker, Sharon Ruthstein, Haim Cohen

The modification of nitrogen-contaminated diamonds into color-enhanced diamonds is usually achieved by irradiation and thermal treatment (annealing). These treatments affect nitrogen contamination chemical bonding, vacancy concentration, and atom orientation centers in the diamond lattice. In this study, natural diamonds were subjected to irradiation and thermal annealing color enhancement treatments to produce green, blue, and yellow fancy diamonds. The study followed the changes that occur during treatment relying on visual assessment, fluorescence, UV-vis, FTIR, and EPR spectroscopy to characterize paramagnetic centers. The results indicated that diamonds containing high levels of nitrogen contamination presented a relatively high carbon-centered radical concentration. Two paramagnetic groups with different g-values were found, namely, low g-value centers of 2.0017–2.0027 and high g-value …

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2022 • RSC advances

Prospect of making XPS a high-throughput analytical method illustrated for a Cu x Ni 1− x O y combinatorial material library

Lucas CW Bodenstein-Dresler, Adi Kama, Johannes Frisch, Claudia Hartmann, Anat Itzhak, Regan G Wilks, David Cahen, Marcus Bär

Combinatorial material science crucially depends on robust, high-throughput characterization methods. While X-ray photoelectron spectroscopy (XPS) may provide detailed information about chemical and electronic properties, it is a time-consuming technique and, therefore, is not viewed as a high-throughput method. Here we present preliminary XPS data of 169 measurement spots on a combinatorial 72 × 72 cm2 CuxNi1−xOy compositional library to explore how characterization and evaluation routines can be optimized to improve throughput in XPS for combinatorial studies. In particular, two quantification approaches are compared. We find that a simple integration (of XPS peak regions) approach is suited for fast evaluation of, in the example system, the [Cu]/([Cu] + [Ni]) ratio. Complementary to that, the time-consuming (XPS peak-) fit approach provides additional insights into chemical speciation and oxidation …

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2022 • Chemical Science

Cu (II)-based DNA Labeling Identifies the Structural Link Between Activation and Termination in a Metalloregulator

Joshua Casto, Alysia Mandato, Lukas Hofmann, Idan Yakobov, Shreya Ghosh, Sharon Ruthstein, Sunil Saxena

2022 • Optics and Lasers in Engineering

Loss minimized data reduction in single-cell tomographic phase microscopy using 3D zernike descriptors

P Memmolo, D Pirone, DG Sirico, L Miccio, V Bianco, AB Ayoub, D Psaltis, P Ferraro, AM Caravaca-Aguirre, F Poisson, D Bouchet, N Stasio, P Moreau, I Wang, E Zhang, P Beard, C Prada, C Moser, O Katz, E Bossy, NU Dinc, A Saba, J Madrid-Wolff, C Gigli, A Boniface, Ab Ayoub, J Lim, F Merola, M Mugnano, F Cimmino, NU Dinç, S Gigan, HB de Aguiar, E Andresen, B Rahmani, I Oguz, U Tegin, J Hsieh, A Roy, G Panusa, Z Liu, K Shi, EE Antoine, X Laporte, J Moughames, C Juliano, M Kadic, D Brunner, M Yildirim, U Teğin, P Hadikhani, SMH Hashemi, SA Schenk, K Skarsoulis, E Kakkava, E Antoine, G Wetzstein, A Ozcan, S Fan, D Englund, M Soljacic, C Denz, DAB Miller, Y Pu, J Wang, T Thomsen, HA Klok, P Hadikhani, S Mohammad H Hashemi, D Loterie, N Borhani, G Konstantinou, L Hagelüken, PVW Sasikumar, MG Makowska, G Blugan, N Nianias, F Marone, H Van Swygenhoven, J Brügger, P Vallachira Warriam Sasikumar, E Müller, P Clement, J Jang, K Maniura-Weber, M Rottmar, J Bruegger, K Goda, G Popescu, KK Tsia, M Hashemi, U Babic, T Pham, E Soubies, A Ayoub, M Unser, ME Edri, H Shpaisman, Z Zalevsky, M Romito

Publications ‒ LO ‐ EPFL Skip to content Logo EPFL, École polytechnique fédérale de Lausanne About Education Research Innovation Schools Campus Search on the site Validate Show / hide the search form Search on the site Hide the search form EN Menu Browse 2.STI IEM Advanced manufacturing Energy systems Future of computing Imaging and vision Learning and decision systems Neural engineering and prosthetics Optics and photonics Soft matter and flexible structures 3.Laboratories 4.Publications Publications For further details of the Psaltis’ Group publications visit Google Scholar @ 2023 Toward the specificity in QPI 3D tomographic cell flow cytometry holography: recent achievements and perspectives in biomedical sciences D Pirone, J Lim, F Merola, L Miccio, M Mugnano, V Bianco, M Valentino, G Giugliano, F Cimmino, F Visconte, A Montella, M Capasso, A Lolascon, P Memmolo, D Psaltis, P …

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2022 • s Note: MDPI stays neutral with regard to jurisdictional claims in published …, 2022

Magnetite nanoparticles: Synthesis and applications in optics and nanophotonics. Materials 2022, 15, 2601

N Dudchenko, S Pawar, I Perelshtein, D Fixler

Magnetite nanoparticles with different surface coverages are of great interest for many applications due to their intrinsic magnetic properties, nanometer size, and definite surface morphology. Magnetite nanoparticles are widely used for different medical-biological applications while their usage in optics is not as widespread. In recent years, nanomagnetite suspensions, so-called magnetic ferrofluids, are applied in optics due to their magneto-optical properties. This review gives an overview of nanomagnetite synthesis and its properties. In addition, the preparation and application of magnetic nanofluids in optics, nanophotonics, and magnetic imaging are described.

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2022 • Physical Chemistry Chemical Physics

Cu 2+-Induced self-assembly and amyloid formation of a cyclic d, l-α-peptide: structure and function

Daniel Klose, Sahithya Phani Babu Vemulapalli, Michal Richman, Safra Rudnick, Vered Aisha, Meital Abayev, Marina Chemerovski, Meital Shviro, David Zitoun, Katharina Majer, Nino Wili, Gil Goobes, Christian Griesinger, Gunnar Jeschke, Shai Rahimipour

In a wide spectrum of neurodegenerative diseases, self-assembly of pathogenic proteins to cytotoxic intermediates is accelerated by the presence of metal ions such as Cu2+. Only low concentrations of these early transient oligomeric intermediates are present in a mixture of species during fibril formation, and hence information on the extent of structuring of these oligomers is still largely unknown. Here, we investigate dimers as the first intermediates in the Cu2+-driven aggregation of a cyclic D,L-α-peptide architecture. The unique structural and functional properties of this model system recapitulate the self-assembling properties of amyloidogenic proteins including β-sheet conformation and cross-interaction with pathogenic amyloids. We show that a histidine-rich cyclic D,L-α-octapeptide binds Cu2+ with high affinity and selectivity to generate amyloid-like cross-β-sheet structures. By taking advantage of backbone …

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2022 • Physical Chemistry Chemical Physics

Electron transport via tyrosine-doped oligo-alanine peptide junctions: role of charges and hydrogen bonding

Cunlan Guo, Yulian Gavrilov, Satyajit Gupta, Tatyana Bendikov, Yaakov Levy, Ayelet Vilan, Israel Pecht, Mordechai Sheves, David Cahen

A way of modulating the solid-state electron transport (ETp) properties of oligopeptide junctions is presented by charges and internal hydrogen bonding, which affect this process markedly. The ETp properties of a series of tyrosine (Tyr)-containing hexa-alanine peptides, self-assembled in monolayers and sandwiched between gold electrodes, are investigated in response to their protonation state. Inserting a Tyr residue into these peptides enhances the ETp carried via their junctions. Deprotonation of the Tyr-containing peptides causes a further increase of ETp efficiency that depends on this residue's position. Combined results of molecular dynamics simulations and spectroscopic experiments suggest that the increased conductance upon deprotonation is mainly a result of enhanced coupling between the charged C-terminus carboxylate group and the adjacent Au electrode. Moreover, intra-peptide hydrogen …

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