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Jul 2021 • arXiv preprint arXiv:2107.10904

Anomalous Transport in High-Mobility Superconducting SrTiO Thin Films

Jin Yue, Yilikal Ayino, Tristan K Truttmann, Maria N Gastiasoro, Eylon Persky, Alex Khanukov, Dooyong Lee, Laxman R Thoutam, Beena Kalisky, Rafael M Fernandes, Vlad S Pribiag, Bharat Jalan

The study of subtle effects on transport in semiconductors requires high-quality epitaxial structures with low defect density. Using hybrid molecular beam epitaxy (MBE), SrTiO films with low-temperature mobility exceeding 42,000 cmVs at low carrier density of 3 x 10 cm were achieved. A sudden and sharp decrease in residual resistivity accompanied by an enhancement in the superconducting transition temperature were observed across the second Lifshitz transition (LT) where the third band becomes occupied, revealing dominant intra-band scattering. These films further revealed an anomalous behavior in the Hall carrier density as a consequence of the antiferrodistortive (AFD) transition and the temperature-dependence of the Hall scattering factor. Using hybrid MBE growth, phenomenological modeling, temperature-dependent transport measurements, and scanning superconducting quantum interference device imaging, we provide critical insights into the important role of inter- vs intra-band scattering and of AFD domain walls on normal-state and superconducting properties of SrTiO.

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Jul 2021 • Membranes

Antibacterial and In Vivo Studies of a Green, One-Pot Preparation of Copper/Zinc Oxide Nanoparticle-Coated Bandages

Archana R Deokar, Ilana Perelshtein, Melissa Saibene, Nina Perkas, Paride Mantecca, Yeshayahu Nitzan, Aharon Gedanken

Simultaneous water and ethanol-based synthesis and coating of copper and zinc oxide (CuO/ZnO) nanoparticles (NPs) on bandages was carried out by ultrasound irradiation. High resolution-transmission electron microscopy demonstrated the effects of the solvent on the particle size and shape of metal oxide NPs. An antibacterial activity study of metal-oxide-coated bandages was carried out against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative). CuO NP-coated bandages made from both water and ethanol demonstrated complete killing of S. aureus and E. coli bacteria within 30 min., whereas ZnO NP-coated bandages demonstrated five-log reductions in viability for both kinds of bacteria after 60 min of interaction. Further, the antibacterial mechanism of CuO/ZnO NP-coated bandages is proposed here based on electron spin resonance studies. Nanotoxicology investigations were conducted via in vivo examinations of the effect of the metal-oxide bandages on frog embryos (teratogenesis assay—Xenopus). The results show that water-based coatings resulted in lesser impacts on embryo development than the ethanol-based ones. These bandages should therefore be considered safer than the ethanol-based ones. The comparison between the toxicity of the metal oxide NPs prepared in water and ethanol is of great importance, because water will replace ethanol for bulk scale synthesis of metal oxide NPs in commercial companies to avoid further ignition problems. The novelty and importance of this manuscript is avoiding the ethanol in the typical water: ethanol mixture as the solvent for the preparation of metal …

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Jul 2021 • Journal of Visualized Experiments: Jove

Fabrication of Magnetic Platforms for Micron-Scale Organization of Interconnected Neurons

Ganit Indech, Reut Plen, Dafna Levenberg, Naor Vardi, Michal Marcus, Alejandra Smith, Shlomo Margel, Orit Shefi, Amos Sharoni

The ability to direct neurons into organized neural networks has great implications for regenerative medicine, tissue engineering, and bio-interfacing. Many studies have aimed at directing neurons using chemical and topographical cues. However, reports of organizational control on a micron-scale over large areas are scarce. Here, an effective method has been described for placing neurons in preset sites and guiding neuronal outgrowth with micron-scale resolution, using magnetic platforms embedded with micro-patterned, magnetic elements. It has been demonstrated that loading neurons with magnetic nanoparticles (MNPs) converts them into sensitive magnetic units that can be influenced by magnetic gradients. Following this approach, a unique magnetic platform has been fabricated on which PC12 cells, a common neuron-like model, were plated and loaded with superparamagnetic nanoparticles. Thin films of ferromagnetic (FM) multilayers with stable perpendicular magnetization were deposited to provide effective attraction forces toward the magnetic patterns. These MNP-loaded PC12 cells, plated and differentiated atop the magnetic platforms, were preferentially attached to the magnetic patterns, and the neurite outgrowth was well aligned with the pattern shape, forming oriented networks. Quantitative characterization methods of the magnetic properties, cellular MNP uptake, cell viability, and statistical analysis of the results are presented. This approach enables the control of neural network formation and improves neuron-to-electrode interface through the manipulation of magnetic forces, which can be an effective tool for in vitro …

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Jul 2021 • Pharmaceuticals

Tumor-targeted fluorescent proteinoid nanocapsules encapsulating synergistic drugs for personalized cancer therapy

Ella Itzhaki, Elad Hadad, Neta Moskovits, Salomon M Stemmer, Shlomo Margel

Personalized cancer treatment based on specific mutations offers targeted therapy and is preferred over “standard” chemotherapy. Proteinoid polymers produced by thermal step-growth polymerization of amino acids may form nanocapsules (NCs) that encapsulate drugs overcoming miscibility problems and allowing passive targeted delivery with reduced side effects. The arginine-glycine-glutamic acid (RGD) sequence is known for its preferential attraction to αvβ3 integrin, which is highly expressed on neovascular endothelial cells that support tumor growth. Here, tumor-targeted RGD-based proteinoid NCs entrapping a synergistic combination of Palbociclib (Pal) and Alpelisib (Alp) were synthesized by self-assembly to induce the reduction of tumor cell growth in different types of cancers. The diameters of the hollow and drug encapsulating poly(RGD) NCs were 34 ± 5 and 22 ± 3 nm, respectively; thereby, their drug targeted efficiency is due to both passive and active targeting. The encapsulation yield of Pal and Alp was 70 and 90%, respectively. In vitro experiments with A549, MCF7 and HCT116 human cancer cells demonstrate a synergistic effect of Pal and Alp, controlled release and dose dependence. Preliminary results in a 3D tumor spheroid model with cells derived from patient-derived xenografts of colon cancer illustrate disassembly of spheroids, indicating that the NCs have therapeutic potential.

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Jul 2021 • Optics Letters

Cross-phase modulation aberrations in time lenses

Hamootal Duadi, Avi Klein, Inbar Sibony, Sara Meir, Moti Fridman

We study the aberrations of four-wave mixing based time lenses resulting from the cross-phase modulations of the pump wave. These temporal aberrations have no spatial equivalent and are important when imaging weak signals with strong pump waves. We show that as the pump power increases, the cross-phase modulations of the pump are responsible for shifting, defocusing, and imposing temporal coma aberrations on the image. We present experimental results of these aberrations with high agreement to analytical and numerical calculations.

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Jul 2021 • Nature Protocols 16 (7), 3264-3297, 2021

Design of metal-mediated protein assemblies via hydroxamic acid functionalities

Rohit H Subramanian, Jie Zhu, Jake B Bailey, Jerika A Chiong, Yiying Li, Eyal Golub, F Akif Tezcan

The self-assembly of proteins into sophisticated multicomponent assemblies is a hallmark of all living systems and has spawned extensive efforts in the construction of novel synthetic protein architectures with emergent functional properties. Protein assemblies in nature are formed via selective association of multiple protein surfaces through intricate noncovalent protein–protein interactions, a challenging task to accurately replicate in the de novo design of multiprotein systems. In this protocol, we describe the application of metal-coordinating hydroxamate (HA) motifs to direct the metal-mediated assembly of polyhedral protein architectures and 3D crystalline protein–metal–organic frameworks (protein-MOFs). This strategy has been implemented using an asymmetric cytochrome cb562 monomer through selective, concurrent association of Fe3+ and Zn2+ ions to form polyhedral cages. Furthermore, the use of …

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Jul 2021

Use of cell doublets for studying cytokinesis regulation reveals a new form of cytokinesis regression

E Panet, SHO Shalom, O Kraus, I Shoval, R Lahmi, H Shapiro, A Tzur

Cytokinesis mediates separation of daughter cells at the end of cell division. We have developed a high-throughput approach for monitoring cell-autonomous cytokinesis in non-adherent cells. Focusing on cytokinesis termination, we show that chemical inhibition of protein phosphatase 1 (PP1) and PP2A specifically in late cytokinesis activates cytokinesis regression, which is distinct from any known cytokinesis failure, and is not a by-product of abnormal furrow ingression or chromatin bridges. This process is characterized by the formation of cortical blebs primarily at the intercellular bridge, reopening of the cleavage furrow and reassembly of an interphase-like microtubule network, but not by chromatin recondensation and mitotic spindle formation. Finally, cytokinesis regression is suppressed by chemical inhibition of aurora kinases but not Cdk1 or PLK1. Altogether, our results highlight a hitherto uncharacterized facet of the counter-activity of PP1/PP2A and aurora kinases in the final step of cell division, which ultimately secure the conclusion of cytokinesis, thereby preventing polyploidy and genomic instability.

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Jul 2021

Use of cell doublets for studying cytokinesis regulation reveals a new form of cytokinesis regression

Nofar Levi-Dadon, Einat Panet, Shira Huri Ohev Shalom, Ohad Kraus, Irit Shoval, Roxane Lahmi, Howard Shapiro, Amit Tzur

Page 1. Use of cell doublets for studying cytokinesis regulation reveals a new form of cytokinesis regression Nofar Levi-Dadon1 Bar-Ilan University Einat Panet Bar-Ilan University Shira Huri Ohev Shalom Bar-Ilan University Ohad Kraus Bar-Ilan University Irit Shoval Bar-Ilan University Roxane Lahmi Bar-Ilan University Howard Shapiro The Center for Microbial Cytometry, West Newton, MA, USA Amit Tzur (  ) Bar-Ilan University Article Keywords: Cytokinesis regression, Cytokinesis index, Flow cytometry, Doublet discrimination cell- autonomous regulation, lymphocytic leukemia cells L1210 DOI: License:   This work is licensed under a Creative Commons Attribution 4.0 International License …

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Jul 2021 • 2021 IEEE 21st International Conference on Nanotechnology (NANO), 389-392, 2021

Electronic Transport Through Organophosphonate-Grafted Bacteriorhodopsin Films on Titanium Nitride

Domenikos Chryssikos, Julian M Dlugosch, Jerry A Fereiro, Takuya Kamiyama, Mordechai Sheves, David Cahen, Marc Tornow

Understanding the charge transport properties of proteins at the molecular scale is crucial for the development of novel bioelectronic devices. In this contribution, we report on the preparation and electrical characterization of thin films of bacteriorhodopsin grafted on the surface of titanium nitride via aminophosphonate linkers. Thickness analysis using atomic force microscopy revealed a protein film thickness of 8.2±1.5 nm, indicating the formation of a protein bilayer. Electrical measurements were carried out in the dry state, in a vertical arrangement with a eutectic gallium-indium (EGaIn) or an evaporated Ti/Au top contact. DC current-voltage measurements yielded comparable effective tunneling decay constants for the EGaIn top contact and for the Ti/Au top contact. The results presented herein may establish a novel platform for studying charge transport via protein molecules in a solid-state …

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Jul 2021 • Journal of experimental botany

Corrigendum to: Siliplant1 protein precipitates silica in sorghum silica cells

Santosh Kumar, Nurit Adiram-Filiba, Shula Blum, Javier Arturo Sanchez-Lopez, Oren Tzfadia, Ayelet Omid, Hanne Volpin, Yael Heifetz, Gil Goobes, Rivka Elbaum

J Exp Bot. 2021 Jul 31;erab333. doi: 10.1093/jxb/erab333. Online ahead of print … 1 Robert H Smith Institute of Plant Sciences and Genetics in Agriculture, Robert H Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, Israel … 2 Electron Microscopy Facility, Centre for Cellular and Molecular Platforms (C-CAMP), National Centre for Biological Sciences (NCBS-TIFR), Bangalore, India … 3 Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel … 4 Department of Entomology, Robert H Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, Israel … 5 Bioinformatics and Systems Biology, VIB/Ghent University, Gent, Belgium … 6 Danziger Innovations Limited, Mishmar Hashiva, Israel.

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Jul 2021 • Optics Express

Effect of optical magnification on the detection of the reduced scattering coefficient in the blue regime: theory and experiments

Channa Shapira, Inbar Yariv, Rinat Ankri, Hamootal Duadi, Dror Fixler

Imaging turbid media is range limited. In contrast, sensing the medium’s optical properties is possible in larger depths using the iterative multi-plane optical properties extraction technique. It analyzes the reconstructed reemitted light phase image. The root mean square of the phase image yields two graphs with opposite behaviors that intersect at µ’s,cp. These graphs enable the extraction of a certain range of the reduced scattering coefficient, µ’s. Here, we aim to extend the range of µ’s detection by optical magnification. We use a modified diffusion theory and show how µ’s,cp shifts with the varying magnification. The theoretical results were tested experimentally, showing that the technique can be adapted to different ranges of µ’s by changing the magnification.

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Jul 2021 • Physical Review D

Experimental observation of acceleration-induced thermality

and Ido Kaminer Morgan H. Lynch, Eliahu Cohen, Yaron Hadad

Jul 2021 • Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology


S Sudri, I Allon, I Abu El-Naaj, D Fixler, A Hirshberg

BackgroundNanoparticle-based contrast agents have been used as an imaging tool for selectively detecting cancerous processes. Epidermal growth factor receptor (EGFR) has been found to be dysregulated in malignant salivary gland tumors (MSGTs) and can serve as an ideal target for nanoparticle-based contrast agents using gold nanoparticles (GNPs) bio-conjugated to anti-EGFR monoclonal antibodies.ObjectiveTo evaluate the detection sensitivity of reflection measurements of anti-EGFR conjugated gold nanoparticles (C-GNPs) in discriminating benign tumors from MSGT.MethodsTissue sections of 37 cases were investigate. Nineteen cases of MSGT and 9 cases of benign tumors and 9 normal salivary glands were incubated with C-GNPs and the reflectance spectrum was measured using hyperspectral microscopy.ResultsA significant trend was found to correlate the severity of the lesions (Cuzick's test for …

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Jul 2021 • ACS Catalysis

Site-Independent Hydrogenation Reactions on Oxide-Supported Au Nanoparticles Facilitated by Intraparticle Hydrogen Atom Diffusion

Shahar Dery, Hillel Mehlman, Lillian Hale, Mazal Carmiel-Kostan, Reut Yemini, Tzipora Ben-Tzvi, Malachi Noked, F Dean Toste, Elad Gross

Metal–support interactions have been widely utilized for optimizing the catalytic reactivity of oxide-supported Au nanoparticles. Optimized reactivity was mainly detected with small (1–5 nm) oxide-supported Au nanoparticles and correlated to highly reactive sites at the oxide–metal interface. However, catalytically active sites are not necessarily restricted to the interface but reside as well on the Au surface. Uncovering the interconnection between reactive sites located at the interface and those situated at the metal surface is of crucial importance for understanding the reaction mechanism on Au nanoparticles. Herein, high-spatial-resolution IR nanospectroscopy measurements were conducted to map the localized reactivity in hydrogenation reactions on oxide-supported Au particles while using nitro-functionalized ligands as probes molecules. Comparative analysis of the reactivity pattern on single particles supported …

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Jul 2021 • Biology

A Gut-Ex-Vivo System to Study Gut Inflammation Associated to Inflammatory Bowel Disease (IBD)

Mara Gagliardi, Romina Monzani, Nausicaa Clemente, Luca Fusaro, Valentina Saverio, Giovanna Grieco, Elżbieta Pańczyszyn, Nissan Yissachar, Francesca Boccafoschi, Marco Corazzari

Inflammatory bowel disease (IBD) is a complex, chronic, and dysregulated inflammatory condition which etiology is still largely unknown. Its prognosis and disease progression are highly variable and unpredictable. IBD comprises several heterogeneous inflammatory conditions ranging from Ulcerative Colitis (UC) to Crohn’s Disease (CD). Importantly, a definite, well-established, and effective clinical treatment for these pathologies is still lacking. The urgent need for treatment is further supported by the notion that patients affected by UC or CD are also at risk of developing cancer. Therefore, a deeper understanding of the molecular mechanisms at the basis of IBD development and progression is strictly required to design new and efficient therapeutic regimens. Although the development of animal models has undoubtedly facilitated the study of IBD, such in vivo approaches are often expensive and time-consuming. Here we propose an organ ex vivo culture (Gut-Ex-Vivo system, GEVS) based on colon from Balb/c mice cultivated in a dynamic condition, able to model the biochemical and morphological features of the mouse models exposed to DNBS (5–12 days), in 5 h. Indeed, upon DNBS exposure, we observed a dose-dependent:(i) up-regulation of the stress-related protein transglutaminase 2 (TG2);(ii) increased intestinal permeability associated with deregulated tight junction protein expression;(iii) increased expression of pro-inflammatory cytokines, such as

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Jul 2021 • IEEE Photonics Journal

Effect of Spatial Modulated Light on Position of Self-Calibration Point

Idit Feder, Hamootal Duadi, Dror Fixler

In optical sensing, the differentiation between absorption and scattering poses a challenge when dealing with a physiological medium. We have shown that for extracting absorption-based parameters it is optimal to measure at the iso-path length (IPL) point. The IPL position is dependent on the diameter of the medium. In this paper, we will demonstrate how beam shaping can help match the light pattern, so the IPL point remains in the same position and distance from the light source. Hence, the location of the detector will remain constant for different mediums, such as different fingers. A spatial frequency of 0.4 mm −1 , in the case of a 15mm diameter cylindrical phantoms, shifts the IPL point's position by 40 degrees on the phantom's surface. Moreover, the spatial modulation yields an optical signature from different depths, which could improve the extraction of optical properties from tissue depth using our method.

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Jul 2021 • Biomedical Optics Express

Iterative optical technique for detecting anti-leishmania nanoparticles in mouse lesions

Inbar Yariv, Sriram Kannan, Yifat Harel, Esthy Levy, Hamootal Duadi, Jean-Paul Lellouche, Shulamit Michaeli, Dror Fixler

Nanoparticles (NPs) based drugs for topical administration are gaining interest in the biomedical world. However, a study tool of their penetration depth to the different tissue layers without additional markers or contrast agents is required in order to relieve safety concerns. While common diagnostic tools, e.g. X-ray, computed tomography or magnetic resonance imaging, can provide in vivo detection of the metallic NPs, their resolution cannot determine the exact penetration depth to the thin skin layers. In this work, we propose the noninvasive nanophotonics iterative multi-plane optical property extraction (IMOPE) technique for the novel iron-based NPs detection in leishmaniasis lesions. The optical properties of the different tissue layers: epidermis, dermis, subcutaneous fat and muscle, were examined before and after topical drug administration. The potential topical drug was detected in the epidermis (∼13µm) and …

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Jul 2021 • Physical Review A

Three approaches for analyzing the counterfactuality of counterfactual protocols

Alon Wander, Eliahu Cohen, Lev Vaidman

Counterfactual communication protocols are analyzed using three approaches: a classical argument, the weak trace criterion, and the Fisher information criterion. It is argued that the classical analysis leads to contradiction and should therefore be abandoned. The weak trace and Fisher information criteria are shown to agree about the degree of counterfactuality of communication protocols involving postselection. It is argued that postselection is a necessary ingredient of counterfactual communication protocols. Coherent interaction experiments, as well as a recently introduced modification of counterfactual communication setups which eliminates the weak trace, are discussed.

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Jul 2021 • ACS applied materials & interfaces

Laser Printing of Multilayered Alternately Conducting and Insulating Microstructures

Eitan Edri, Nina Armon, Ehud Greenberg, Shlomit Moshe-Tsurel, Danielle Lubotzky, Tommaso Salzillo, Ilana Perelshtein, Maria Tkachev, Olga Girshevitz, Hagay Shpaisman

Production of multilayered microstructures composed of conducting and insulating materials is of great interest as they can be utilized as microelectronic components. Current proposed fabrication methods of these microstructures include top-down and bottom-up methods, each having their own set of drawbacks. Laser-based methods were shown to pattern various materials with micron/sub-micron resolution; however, multilayered structures demonstrating conducting/insulating/conducting properties were not yet realized. Here, we demonstrate laser printing of multilayered microstructures consisting of conducting platinum and insulating silicon oxide layers by a combination of thermally driven reactions with microbubble-assisted printing. PtCl2 dissolved in N-methyl-2-pyrrolidone (NMP) was used as a precursor to form conducting Pt layers, while tetraethyl orthosilicate dissolved in NMP formed insulating silicon …

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Jul 2021 • FEBS OPEN BIO 11, 16-16, 2021

Matrix remodeling as early pathophysiological biomarker

I Sagi, E Shimshoni, I Adir, I Solomonov

Jun 2021 • Chemical Communications (Cambridge, England)

Combining polarized low-frequency Raman with XRD to identify directional structural motifs in a pyrolysis precursor.

Ben Uliel, Eliyahu M Farber, Hagit Aviv, Wowa Stroek, Marilena Farbinteanu, Yaakov R Tischler, David Eisenberg


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