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Prospect of making XPS a high-throughput analytical method illustrated for a CuₓNi₁₋ ₓOy 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 state changes, without a large deviation of the [Cu]/([Cu] + [Ni]) ratio. This insight suggests exploiting the fast integration approach for ‘real time’ analysis during XPS data collection, paving the way for an ‘on-the-fly’ selection of points of interest (i.e., areas on the sample where sudden composition changes have been identified) for detailed XPS characterization. Together with the envisioned improvements when going from laboratory to synchrotron-based excitation sources, this will shorten the analysis time sufficiently for XPS to become a realistic characterization option for combinatorial material science.

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2022 • Frontiers in Molecular Biosciences

Disrupting Cu trafficking as a potential therapy for cancer

Zena Qasem, Matic Pavlin, Ida Ritacco, Matan Y Avivi, Shelly Meron, Melanie Hirsch, Yulia Shenberger, Lada Gevorkyan-Airapetov, Alessandra Magistrato, Sharon Ruthstein

Copper is an essential trace element required for vital cell functions and the survival of all organisms, ranging from bacteria to humans (Burkhead et al., 2009; Gaggelli et al., 2009; Lutsenko, 2010). Owing to the ability of copper to cycle between two oxidation states [ie, Cu (I) and Cu (II)], copper ions serve as important catalytic cofactors in proteinlinked redox chemistry. Such proteins carry out fundamental biological functions and are required for proper cellular growth and development. Copper-dependent proteins are involved in a wide variety of biological processes. Therefore, copper deficiency in these enzymes and/or alterations in their functions often trigger disease states or physiopathological conditions. Although critical for proper cell functioning, copper ions can also act as potent cytotoxins (Bertinato and L’Abbe, 2004; Manto, 2014; Harrison and Dameron, 1999). Owing to its special redox chemistry, copper …

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2022 • Polymers for Advanced Technologies

Chirality of proteinoid nanoparticles made of lysine and phenylalanine

Liroy Lugasi, Gil Otis, Matan Oliel, Shlomo Margel, Yitzhak Mastai

Proteinoid nanoparticles composed of l‐lysine and l‐phenylalanine were prepared and showed enantioselective adsorption of l‐amino acids at various pH values, emphasizing the chiral nature of the particles. The adsorption was examined using circular dichroism, isothermal titration calorimetry and ζ‐potential measurements. Positively charged ammonium moieties on the proteinoid surface are most likely responsible for the enantioselective adsorption owing to their chirality which originates from l‐lysine. Accordingly, a higher enantiomeric excess was found for amino acids such as alanine with a more negative charge.

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2022 • Chemical Communications

Photoacoustic measurement of localized optical dichroism in chiral crystals

Gil Otis, Matan Benyamin, Yitzhak Mastai, Zeev Zalevsky

In this communication, we present a novel method to measure local optical dichroism (OD) in opaque crystal powder suspensions using photoacoustic (PA) effect. Our method is based upon the novel laser speckle contrast technique, in combination with a simple statistical approach, we were able to measure the OD of chiral crystals suspensions under completely random orientation.

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2022 • Forward Brillouin Scattering in Standard Optical Fibers: Single-Mode …, 2022

Forward Brillouin Scattering Spectra in Coated Single-Mode Fibers

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

The analysis of forward stimulated Brillouin scattering is extended to standard single-mode fibers with coating layers. The cutoff frequencies, linewidths, and transverse profiles of the guided acoustic modes are modified by the presence of the coating layer and by its mechanical properties. The solutions are generally more complex than those of bare, uncoated fibers. Nevertheless, the boundary conditions can be brought into the form of matrix coefficients and solved to obtain the guided modes of the coated fibers. The forward stimulated Brillouin scattering of coated fibers is highly sensitive of submicron variations in the thickness of the coating layer, due to interference effects. Some modes are more sensitive to such variations than others. In contrast to bare fibers, the forward Brillouin scattering linewidths of coated fibers do not maintain a one-to-one correspondence with the mechanical impedance of media outside …

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

Simultaneous Noninvasive Detection and Therapy of Atherosclerosis Using HDL Coated Gold Nanorods. Diagnostics 2022, 12, 577

R Ankri, D Leshem-Lev, H Duadi, E Harari, M Motiei, E Hochhauser, EI Lev, D Fixler

Cardiovascular disease (CVD) is a major cause of death and disability worldwide. A real need exists in the development of new, improved therapeutic methods for treating CVD, while major advances in nanotechnology have opened new avenues in this field. In this paper, we report the use of gold nanoparticles (GNPs) coated with high-density lipoprotein (HDL)(GNP-HDL) for the simultaneous detection and therapy of unstable plaques. Based on the well-known HDL cardiovascular protection, by promoting the reverse cholesterol transport (RCT), injured rat carotids, as a model for unstable plaques, were injected with the GNP-HDL. Noninvasive detection of the plaques 24 h post the GNP injection was enabled using the diffusion reflection (DR) method, indicating that the GNP-HDL particles had accumulated in the injured site. Pathology and noninvasive CT measurements proved the recovery of the injured artery treated with the GNP-HDL. The DR of the GNP-HDL presented a simple and highly sensitive method at a low cost, resulting in simultaneous specific unstable plaque diagnosis and recovery.

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2022 • Frontiers in Physics

High Spatio-Temporal Resolution Condenser-Free Quantitative Phase Contrast Microscopy

Ying Ma, Lin Ma, Juanjuan Zheng, Min Liu, Zeev Zalevsky, Peng Gao

2022 • Forward Brillouin Scattering in Standard Optical Fibers: Single-Mode …, 2022

Spontaneous Forward Brillouin Scattering in Standard Single-Mode Fibers

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

This chapter studies spontaneous scattering of light in single-mode fibers, due to the photoelastic perturbations associated with the oscillations of guided acoustic modes. The acoustic modes, in this case, are not stimulated by the optical fields being observed. Instead, they may be of thermal origin or driven by other optical field components than those monitored. Scattering is formulated in terms of nonlinear polarization terms and nonlinear wave equations for the evolution of the spectral sidebands of an input optical field. In the case of radial guided acoustic modes, photoelastic scattering of the optical field results in its phase modulation. By contrast, torsional-radial acoustic modes may induce phase modulation, coupling to the orthogonal polarization, or a combination of both, depending on the state of polarization of the input optical field. The strength of modulation is quantified in terms of a nonlinear coefficient …

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2022 • Soft Matter

Network model of active elastic shells swollen by hydrostatic pressure

Ajoy Maji, Yitzhak Rabin

Many organisms have an elastic skeleton that consists of a closed shell of epithelial cells that is filled with fluid, and can actively regulate both elastic forces in the shell and hydrostatic pressure inside it. In this work we introduce a simple network model of such pressure-stabilized active elastic shells in which cross-links are represented by material points connected by non-linear springs of some given equilibrium lengths and spring constants. We mimic active contractile forces in the system by changing the parameters of randomly chosen springs and use computer simulations to study the resulting local and global deformation dynamics of the network. We elucidate the statistical properties of these deformations by computing the corresponding distributions and correlation functions. We show that pressure-induced stretching of the network introduces coupling between its local and global behavior: while the network …

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2022 • Small

Bridging 1D Inorganic and Organic Synthesis to Fabricate Ultrathin Bismuth‐Based Nanotubes with Controllable Size as Anode Materials for Secondary Li Batteries

Kai Zong, Tianzhi Chu, Dongqing Liu, Andleeb Mehmood, Tianju Fan, Waseem Raza, Arshad Hussain, Yonggui Deng, Wei Liu, Ali Saad, Jie Zhao, Ying Li, Doron Aurbach, Xingke Cai

The growth of ultrathin 1D inorganic nanomaterials with controlled diameters remains challenging by current synthetic approaches. A polymer chain templated method is developed to synthesize ultrathin Bi2O2CO3 nanotubes. This formation of nanotubes is a consequence of registry between the electrostatic absorption of functional groups on polymer template and the growth habit of Bi2O2CO3. The bulk bismuth precursor is broken into nanoparticles and anchored onto the polymer chain periodically. These nanoparticles react with the functional groups and gradually evolve into Bi2O2CO3 nanotubes along the chain. 5.0 and 3.0 nm tubes with narrow diameter deviation are synthesized by using branched polyethyleneimine and polyvinylpyrrolidone as the templates, respectively. Such Bi2O2CO3 nanotubes show a decent lithium‐ion storage capacity of around 600 mA h g−1 at 0.1 A g−1 after 500 cycles, higher …

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2022 • Proc. of SPIE Vol

Quantum hard x-ray microscopy with undetected photons

Haim Aknin, Sharon Shwartz

We explore the possibility for implementing nanoscale quantum imaging based on the concept of undetected photons with a pumping beam at x-ray wavelengths. Our proposed scheme exploits the nearly four order of magnitude angular magnification that is a result of the process of the effect of extreme non-degenerate spontaneous down conversion from xrays into optical radiation, which is used for the generation of entangled photon pairs with one x-ray photon and one visible photon. In our scheme the x-ray photons interact with the object and the visible do not interact with the object, but in contrast to other schemes like ghost imaging, only the visible photons are detected. The scheme is sensitive to both the amplitude and the phase variations and can provide resolutions down to a few nanometers, hence can be used as a powerful tool for nanoscale imaging. In the present configuration, the scheme requires very …

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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 inter-mediates 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 aggrega-tion of a cyclic D,L-α-peptide architecture. The unique structural and functional properties of this model system recapitu-late 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 …

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2022 • Chemical Communications

Redox-and metal-directed structural diversification in designed metalloprotein assemblies

Albert Kakkis, Eyal Golub, Tae Su Choi, F Akif Tezcan

Herein we describe a designed protein building block whose self-assembly behaviour is dually gated by the redox state of disulphide bonds and the identity of exogenous metal ions. This protein construct is shown – through extensive structural and biophysical characterization – to access five distinct oligomeric states, exemplifying how the complex interplay between hydrophobic, metal–ligand, and reversible covalent interactions could be harnessed to obtain multiple, responsive protein architectures from a single building block.

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2022 • Magnetochemistry 8 (1), 3, 2022

The Advantages of EPR Spectroscopy in Exploring Diamagnetic Metal Ion Binding and Transfer Mechanisms in Biological Systems

Shelly Meron, Yulia Shenberger, Sharon Ruthstein

Electron paramagnetic resonance (EPR) spectroscopy has emerged as an ideal biophysical tool to study complex biological processes. EPR spectroscopy can follow minor conformational changes in various proteins as a function of ligand or protein binding or interactions with high resolution and sensitivity. Resolving cellular mechanisms, involving small ligand binding or metal ion transfer, is not trivial and cannot be studied using conventional biophysical tools. In recent years, our group has been using EPR spectroscopy to study the mechanism underlying copper ion transfer in eukaryotic and prokaryotic systems. This mini-review focuses on our achievements following copper metal coordination in the diamagnetic oxidation state, Cu(I), between biomolecules. We discuss the conformational changes induced in proteins upon Cu(I) binding, as well as the conformational changes induced in two proteins involved in Cu(I) transfer. We also consider how EPR spectroscopy, together with other biophysical and computational tools, can identify the Cu(I)-binding sites. This work describes the advantages of EPR spectroscopy for studying biological processes that involve small ligand binding and transfer between intracellular proteins.

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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

Atomic and molecular layer deposition (ALD and MLD) are techniques based on surface‐directed self‐limiting reactions that afford deposition of films controlled at the monolayer level and with extreme conformality, even on ultra‐high‐aspect‐ratio and porous substrates. These methodologies are typically used to deposit thin films with desirable physical properties and functionality. Here, the MLD process is harnessed to demonstrate the growth of molecularly thin chiral films that inherit a desirable chemical property directly from the source precursor: using this innovative technique, enantioselective nanosurfaces are managed to be grown. Specifically, the formation of a Zn/Cysteine nanostructure by MLD is demonstrated for both the l‐ and d‐ enantiomers. The reaction and growth mechanism of these chiral hybrid inorganic‐organic nanosurfaces are studied via various experimental procedures; their …

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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

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 indicates 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 • 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 • APS March Meeting Abstracts

Designing chromium (IV) molecular color centers

Daniel Laorenza, Arailym Kairalapova, Samuel Bayliss, Tamar Goldzak, Samuel Greene, Leah Weiss, Pratiti Deb, Peter Mintun, Kelsey Collins, David Awschalom, Timothy Berkelbach, Danna Freedman

Transition metal-based molecular spins are a promising class of chemically tunable quantum bits (qubits), providing precise control over both the physical and electronic structure within a scalable qubit platform. However, molecular systems typically lack an optically addressable ground state spin. To introduce this valuable resource into molecular spins, we recently created a series of chromium (IV) compounds with the desired optical-spin interface through bottom-up design [1]. Here, we illustrate the versatility of this methodology to generate designer molecular color centers by modifying the organic moieties, or ligands, directly bound to the chromium (IV) site. Variation of the surrounding ligands across six unique systems modulates both the optical emission and ground state zero-field splitting (ZFS) energies. Moreover, the small ZFS values allowed for coherent spin manipulation at X-band microwave frequency …

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2022 • Polymers for Advanced Technologies

Electrospinning of polymer nanofibers based on chiral polymeric nanoparticles

Meir Abuaf, Yitzhak Mastai

2022 • Springer, Cham

Regulation of Host Immunity by the Gut Microbiota

Hannah Partney, Nissan Yissachar

Constant exposure to diverse microorganisms has accompanied human evolution and continues to shape immunological development throughout life. In mucosal tissues, both innate and adaptive arms of the immune system are required to support healthy mutualistic interactions with the resident microbiota, while aggressively fighting pathogenic infections. Technological breakthroughs over the past decade facilitated groundbreaking discoveries that transformed our understanding of intestinal immunology and established the gut microbiota as a critical factor that shapes immunological development and function. Indeed, alterations to microbiota composition (dysbiosis) are associated with a wide array of human diseases, including autoimmune diseases, chronic inflammation, the metabolic syndrome, and cancer. In this chapter, we discuss fundamental concepts that underlie microbiota-immune system crosstalks …

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2022 • Proc. of SPIE Vol

Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XIX

Dror Fixler, Ewa M Goldys, Sebastian Wachsmann-Hogiu

Paper Numbering: A unique citation identifier (CID) number is assigned to each article in the Proceedings of SPIE at the time of publication. Utilization of CIDs allows articles to be fully citable as soon as they are published online, and connects the same identifier to all online and print versions of the publication. SPIE uses a seven-digit CID article numbering system structured as follows:▪ The first five digits correspond to the SPIE volume number.▪ The last two digits indicate publication order within the volume using a Base 36 numbering system employing both numerals and letters. These two-number sets start with 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 0A, 0B… 0Z, followed by 10-1Z, 20-2Z, etc. The CID Number appears on each page of the manuscript.

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