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Apr 2024 • Angewandte Chemie International Edition

Tailoring Zirconia Supported Intermetallic Platinum Alloy via Reactive Metal‐Support Interactions for High‐Performing Fuel Cells

Zijie Lin, Nadaraj Sathishkumar, Yu Xia, Shenzhou Li, Xuan Liu, Jialun Mao, Hao Shi, Gang Lu, Tanyuan Wang, Hsing-Lin Wang, Yunhui Huang, Lior Elbaz, Qing Li

Developing efficient and anti‐corrosive oxygen reduction reaction (ORR) catalysts is of great importance for the applications of proton exchange membrane fuel cells (PEMFCs). Herein, we report a novel approach to prepare metal oxides‐supported intermetallic Pt alloy nanoparticles (NPs) via the reactive metal‐support interaction (RMSI) as ORR catalysts, using Ni‐doped cubic ZrO2 (Ni/ZrO2) supported L10‐PtNi NPs as a proof of concept. Benefiting from the Ni migration during RMSI, the oxygen vacancy concentration in the support is increased, leading to an electron enrichment of Pt. The optimal L10‐PtNi‐Ni/ZrO2‐RMSI catalyst achieves remarkably low mass activity (MA) loss (17.8%) after 400,000 accelerated durability test cycles in a half‐cell and exceptional PEMFC performance (MA = 0.76 A mgPt−1 at 0.9 V, peak power density = 1.52/0.92 W cm−2 in H2‐O2/‐air, and 18.4% MA decay after 30,000 …

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Apr 2024 • arXiv preprint arXiv:2404.16999

Atomistic Modelling and Performance Analysis of High-Entropy Layered Anodes and Electrode Electrolyte Interface Dynamics

Amreen Bano, Dan T Major

Van der Waals (vdW) heterostructures have attracted intense interest worldwide that offers several routes to design materials with novel features which can be served various applications. Unfortunately, at present, this method is restricted to a small number of stackable layers. In this work, we report a bulk vdW material consisting of alternative TiS2 and TiSe2 layers vertically arranged as a potential candidate for anode applications. Moreover, with density functional theory (DFT) calculations and ab-initio molecular dynamics (AIMD) simulations, we explored the effect of high entropy on electrochemical performance of the bulk heterostructure (TSS-HS) by substituting Mo6+ and Al3+ at transition metal site (Ti4+). Solvation shell formation at the electrode-electrolyte interface (EEI) was also studied using AIMD to determine the Li-coordination. Our DFT and AIMD analysis showed considerable improvement in the performance of high entropy TSS-HS (TSS-HE) as compared to TSS-HS. Factors responsible for enhanced performance of TSS-HE were 1) Less structural deformation, 2) Strong bonding (Metal-Chalcogen), 3) Better ionic mobility, 4) Higher theoretical specific capacity, 5) Wider operational voltage window, and 6) Faster Li-ion diffusion. Our observations suggests that 'high entropy' can be an effective strategy to design new anode materials for improving electrochemical performance of Li-ion batteries.

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Apr 2024 • Journal of Energy Storage

Boosting the capacity and stability of Na3V2 (PO4) 2F3-2xO2x microspheres, using atomic layer deposition of artificial CEI

Sankalpita Chakrabarty, Tali Sharabani, Sarah Taragin, Reut Yemini, Ananya Maddegalla, Ilana Perelshtein, Ayan Mukherjee, Malachi Noked

Phosphate-based materials [e.g. Na3V2(PO4)2F3-2xO2x; (NVPFO2x;0 < x < 1)] are regarded as a promising intercalation cathodes for Sodium-ion batteries (SIBs) due to their high reversible specific capacity and stability. However, so far only 2 Na ion were demonstrated to be active in these polyanionic cathodes, which limit their capacity. Herein we provide a strategic approach towards electrochemical activation of a 3rd Na ion, which leads to higher capacity, and preserves structural integrity. We synthesize and study a series of NVPFO2x (0 < x < 1) with well-controlled surface morphology and vanadium oxidation state, and study the dependence of the electrochemical behavior on the various composition and morphology. The optimized NVPFO cathode exhibited highest initial specific discharge capacity (131 mA h g−1) indicating the activation of 3rd Na ion. Nevertheless, the material suffers rapid capacity fading …

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Apr 2024 • Journal of The Electrochemical Society

The Role of Zinc Triflate Additive for Improved Electrochemical Performance of Nickel-Rich Layered Oxide Lithium Battery Cathode via Suppression of Interfacial Parasitic Reactions.

Sri Harsha Akella, Shalev Blanga, Melina Zysler, Gal Radovsky, Malachi Noked

Nickel-rich layered oxide cathode materials with low cobalt content, such as LiNi0.90Mn0.05Co0.05O2 (NMC90), have the potential to enable cost-effective, high-energy-density lithium-metal batteries. However, NMC90 cathode materials are prone to severe parasitic reactions at higher voltages during prolonged cycling. The addition of small percentages of electrolyte additives to the neat commercial electrolyte can significantly enhance the overall electrochemical performance of lithium-metal batteries. This study investigates the effects of zinc triflate (Zn(Otf)2) as an electrolyte additive on the enhancement of the electrochemical performances of lithium-metal batteries comprising nickel-rich layered oxide cathode materials. X-ray photoelectron spectroscopy analysis revealed that Zn(Otf)2 decomposition leads to enhanced fluorination at the interfacial layers, which contributes to improved chemical stability. Utilizing …

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Apr 2024 • Energy Storage Materials

Unleashing the Impact of Nb-doped, Single Crystal, Cobalt-free P2-type Na0. 67Ni0. 33Mn0. 67O2 on Elevating the Cycle Life of Sodium-ion Batteries

Abhinanda Sengupta, Ajit Kumar, Amreen Bano, Aakash Ahuja, Harshita Lohani, Sri Harsha Akella, Pratima Kumari, Malachi Noked, Dan T Major, Sagar Mitra

A synergistic stabilization effect in a Nb-doped P2-type single crystal cobalt-free layered oxide cathode material, offering remarkable cycling stability and high-power performance for Na-ion batteries have unveiled in this study. The introduction of Nb in the transition metal layer not only reduces the electronic band gap but also enhances electronic conductivity and mitigates ionic diffusion energy barriers. The induction of a robust Nb-O bond expedites electron and Na+ transfer, contributing to the stabilization of the host structure is further confirmed through the density functional theory calculations, including electron localization function (ELF) and crystal orbital Hamiltonian population (COHP). To the best of our knowledge, this study is the first to demonstrate a homogeneous distribution of niobium throughout the single crystal, specifically doped at the nickel site within the bulk, without inducing atomic-scale surface …

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Apr 2024 • BMC medicine

Colon impairments and inflammation driven by an altered gut microbiota leads to social behavior deficits rescued by hyaluronic acid and celecoxib

Oryan Agranyoni, Debpali Sur, Sivan Amidror, Nuphar Shidlovsky, Anastasia Bagaev, Nissan Yissachar, Albert Pinhasov, Shiri Navon-Venezia

BackgroundThe exact mechanisms linking the gut microbiota and social behavior are still under investigation. We aimed to explore the role of the gut microbiota in shaping social behavior deficits using selectively bred mice possessing dominant (Dom) or submissive (Sub) behavior features. Sub mice exhibit asocial, depressive- and anxiety-like behaviors, as well as systemic inflammation, all of which are shaped by their impaired gut microbiota composition.MethodsAn age-dependent comparative analysis of the gut microbiota composition of Dom and Sub mice was performed using 16S rRNA sequencing, from early infancy to adulthood. Dom and Sub gastrointestinal (GI) tract anatomy, function, and immune profiling analyses were performed using histology, RT-PCR, flow cytometry, cytokine array, and dextran-FITC permeability assays. Short chain fatty acids (SCFA) levels in the colons of Dom and Sub mice were …

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Apr 2024 • Proceedings

High-Frequency Grating-Based Microelectromechanical Systems Actuator

Inês Pires, Inês S Garcia, João Vieira, Zeev Zalevsky, Carlos Calaza, Filipe S Alves, Rosana A Dias

A silicon mechanical-photonic wavelength converter, not based on absorption, has been recently proposed to address the need for all-silicon photodetectors in the infrared spectrum. Its implementation requires high-frequency modulation, from hundreds of kHz to 1 MHz, of a light beam over an area of a few hundred microns. Since the displacement amplitudes of tens of microns at these frequencies are unfeasible, a moving grate is proposed to locally modulate the light. The MEMS actuator, an array of 1 µm-wide 1 µm-spaced beams (100 × 100 µm2 area), achieved displacements of 70 nm at atmospheric pressure and 350 nm under low vacuum, with 10 Vpp actuation at 290 kHz (FOM displacement × frequency2 above previously reported works).

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Apr 2024 • Optics Express

Enhanced imaging with binary circular Dammann Fresnel zone plate

Stefan R Anton, Nadav Shabairou, Stefan G Stanciu, George A Stanciu, Zeev Zalevsky

We introduce a novel approach in optical engineering by combining Dammann gratings with binary Fresnel zone plates to create a unique hybrid optical element with enhanced energetic efficiency of its focal spots. Traditionally, binary Fresnel zone plates focus light at multiple points with varying intensities, while Dammann gratings are renowned for their efficient and uniform light splitting capabilities. Our innovation lies in merging these two elements and generating a binary circular Dammann (varying along the radial direction) Fresnel zone plate that concentrates most of the incident light into a small and desired number of focused points with equal intensities, rather than distributing light’s energy non-equally across multiple points. This novel design significantly enhances the efficiency and precision of light manipulation. It opens new possibilities in applications requiring high-intensity focal points, such as in …

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Apr 2024 • Biosensors

Using Temporally and Spatially Resolved Measurements to Improve the Sensitivity of Fluorescence-Based Immunoassays

Ran Kremer, Shira Roth, Avital Bross, Amos Danielli, Yair Noam

Detecting low concentrations of biomarkers is essential in clinical laboratories. To improve analytical sensitivity, especially in identifying fluorescently labeled molecules, typical optical detection systems, consisting of a photodetector or camera, utilize time-resolved measurements. Taking a different approach, magnetic modulation biosensing (MMB) is a novel technology that combines fluorescently labeled probes and magnetic particles to create a sandwich assay with the target molecules. By concentrating the target molecules and then using time-resolved measurements, MMB provides the rapid and highly sensitive detection of various biomarkers. Here, we propose a novel signal-processing algorithm that enhances the detection and estimation of target molecules at low concentrations. By incorporating both temporally and spatially resolved measurements using human interleukin-8 as a target molecule, we show that the new algorithm provides a 2–4-fold improvement in the limit of detection and an ~25% gain in quantitative resolution.

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Apr 2024 • ACS Omega

Laser Beam Self-Focusing in Silicon at an Absorbed Wavelength by a Vortex Beam in the Same Wavelength

Nadav Shabairou, Zeev Zalevsky, Moshe Sinvani

In this research, we present a novel approach to achieving super-resolution in silicon using the plasma dispersion effect (PDE) that temporarily controls the complex refractive index of matter. By employing a laser vortex pump beam, which is absorbed in the silicon, we can shape the complex refractive index as a gradient index (GRIN) lens, enabling the focusing of a laser probe beam within the material. Our study introduces a single beam at a wavelength of 775 nm for both the pump and the probe beams, offering tunable focusing capabilities and the potential to attain higher spatial resolution. These findings hold significant promise for applications in nanoelectronics and integrated circuit failure analysis, paving the way for advanced semiconductor imaging and analysis techniques.

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Apr 2024 • Materials Today Chemistry

Engineered thin coatings of cross-linked silane polymers with urea group onto polypropylene fabrics for controlled release of thymol against molds in hay

Elisheva Sasson, Eyal Malka, Ayelet Caspi, Naftali Kanovsky, Shlomo Margel

With world population on the rise, animal food source production has significantly increased. Susceptibility of hay and other sources to molds poses a serious threat to food quality and safety. This study proposes an innovative approach to address this issue – an anti-mold fungicide comprising thymol bound on silica urea thin coating of polypropylene fabrics. The coating enhances the thermal stability of thymol allowing prolonged release. Coating composition and morphology as well as thermal stability and release rates were investigated. The coating provided efficient protection against mold growth with no side effects on hay exposed to thymol fumes. The results underscore the potential of this fungicide as a safe and effective hay preservative.

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Apr 2024 • Cancer Research

Abstract LB007: A systematic evaluation of the therapeutic potential of Endogenous-ADAR base editors in cancer prevention and treatment

Rona Merdler-Rabinowicz, Ariel Dadush, Sumeet Patiyal, Padma Sheila Rajagopal, Gulzar Daya, Alejandro Schäffer, Eli Eisenberg, Eytan Ruppin, Erez Y Levanon

Base editing encompasses techniques that efficiently alter specific nucleotides at the DNA or RNA level. Initially explored for inherited diseases, these techniques hold promise for addressing various genetically driven disorders caused by single nucleotide variants (SNVs). The precise programmability of base editors (BEs) for specific sequences allows customization for rare genetic variants, tailoring them to individual patients within affordability and delivery constraints. Cancer stems from the accumulation of mutations. However, the relevance of BEs in cancer therapy is doubted due to the limited types of mutations they can address within tumors. Yet, their untapped potential in the realm of cancer treatment invites exploration. BEs utilize a modified form of a deaminase enzyme to catalyze the conversion of one nucleotide to another by removing an amino group. A 'classic' BE consists of a deaminase, a Cas …

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Apr 2024 • arXiv preprint arXiv:2404.12381

Wavelength-accurate and wafer-scale process for nonlinear frequency mixers in thin-film lithium niobate

CJ Xin, Shengyuan Lu, Jiayu Yang, Amirhassan Shams-Ansari, Boris Desiatov, Letícia S Magalhães, Soumya S Ghosh, Erin McGee, Dylan Renaud, Nicholas Achuthan, Arseniy Zvyagintsev, David Barton III, Neil Sinclair, Marko Lončar

Recent advancements in thin-film lithium niobate (TFLN) photonics have led to a new generation of high-performance electro-optic devices, including modulators, frequency combs, and microwave-to-optical transducers. However, the broader adoption of TFLN-based devices that rely on all-optical nonlinearities have been limited by the sensitivity of quasi-phase matching (QPM), realized via ferroelectric poling, to fabrication tolerances. Here, we propose a scalable fabrication process aimed at improving the wavelength-accuracy of optical frequency mixers in TFLN. In contrast to the conventional pole-before-etch approach, we first define the waveguide in TFLN and then perform ferroelectric poling. This sequence allows for precise metrology before and after waveguide definition to fully capture the geometry imperfections. Systematic errors can also be calibrated by measuring a subset of devices to fine-tune the QPM design for remaining devices on the wafer. Using this method, we fabricated a large number of second harmonic generation devices aimed at generating 737 nm light, with 73% operating within 5 nm of the target wavelength. Furthermore, we also demonstrate thermo-optic tuning and trimming of the devices via cladding deposition, with the former bringing ~96% of tested devices to the target wavelength. Our technique enables the rapid growth of integrated quantum frequency converters, photon pair sources, and optical parametric amplifiers, thus facilitating the integration of TFLN-based nonlinear frequency mixers into more complex and functional photonic systems.

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Mar 2024 • Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XXI …, 2024

Gold nanoparticles for enhanced delivery of chemotherapy

Idan Katzir, Yoray Sharon, Tamar Sadan, Menachem Motiei, Rachela Popovtzer

Chemotherapy is the gold standard for cancer treatment. However, the specific and safe delivery of chemotherapies to cancer cells remains a great challenge. Gold nanoparticles (GNPs) offer a promising solution as carriers for chemotherapy due to their biocompatibility and distinctive physicochemical properties that facilitate precise drug binding and enhanced tumor penetration through the enhanced permeability and retention effect. Here, we have designed GNPs bound to chemotherapies together with glucose coating and studied their cancer cell killing efficacy in a head and neck squamous cell carcinoma cell line. We found that the GNPs bound to chemotherapy had a higher cancer cell killing efficacy as compared to controls, as well as a bystander effect. This GNP-based platform holds promise, for advancing chemotherapy-based cancer treatments.

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Mar 2024 • Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XXI …, 2024

Synthesis and characterization of antibody-conjugated gold nanoparticles for biological applications

Adi Anaki, Tamar Sadan, Menachem Motiei, Rachela Popovtzer

Gold nanoparticles (GNPs) have garnered significant attention in biomedical applications, particularly as versatile platforms for drug delivery and targeted therapy. The conjugation of GNPs with antibodies offers a promising strategy to enhance their specificity and efficacy in various therapeutic approaches. In this study, we focus on synthesizing different types of GNPs conjugated with antibodies and investigate the influence of various synthesis methods on nanoparticle characterization. The results demonstrated that different synthesis methods lead to different degrees of antibody conjugation on the GNP surface and to varied efficiency on biosystems. This work has the potential to outline design principles that could positively affect the development of targeted nanotherapeutics for various biomedical applications.

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Mar 2024 • Nature Communications

Reshaped three-body interactions and the observation of an Efimov state in the continuum

Yaakov Yudkin, Roy Elbaz, José P D’Incao, Paul S Julienne, Lev Khaykovich

Efimov trimers are exotic three-body quantum states that emerge from the different types of three-body continua in the vicinity of two-atom Feshbach resonances. In particular, as the strength of the interaction is decreased to a critical point, an Efimov state merges into the atom-dimer threshold and eventually dissociates into an unbound atom-dimer pair. Here we explore the Efimov state in the vicinity of this critical point using coherent few-body spectroscopy in 7Li atoms using a narrow two-body Feshbach resonance. Contrary to the expectation, we find that the 7Li Efimov trimer does not immediately dissociate when passing the threshold, and survives as a metastable state embedded in the atom-dimer continuum. We identify this behavior with a universal phenomenon related to the emergence of a repulsive interaction in the atom-dimer channel which reshapes the three-body interactions in any system …

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Mar 2024 • Bioinformatics

Digger: directed annotation of immunoglobulin and T cell receptor V, D, and J gene sequences and assemblies

William D Lees, Swati Saha, Gur Yaari, Corey T Watson

Summary Knowledge of immunoglobulin and T cell receptor encoding genes is derived from high-quality genomic sequencing. High throughput sequencing is delivering large volumes of data, and precise, high-throughput approaches to annotation are needed. Digger is an automated tool that identifies coding and regulatory regions of these genes, with results comparable to those obtained by current expert curational methods. Availability and Implementation Digger is published under open source licence at and is available as a Python package and a Docker container.

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Mar 2024 • ACS Sustainable Chemistry & Engineering

Inhibiting Vertical Zinc Growth Using Low-Cost Composite Membranes

Nophar Tubul, Noam Levi, Gil Bergman, Amey Nimkar, Masato Sonoo, Noa Lulu-Bitton, Shlomo Haroush, Yaniv Gelbstein, Daniel Sharon, Netanel Shpigel, Doron Aurbach

Vertical growth of Zn crystals is widely recognized as a primary factor responsible for the premature failure of aqueous Zn batteries. These vertically aligned sharp-tipped Zn plates can easily pierce the separator, propagating toward the cathode side, and short-circuit the cell. While inhibition of this phenomenon may be achieved by electrolyte engineering or manipulation of the anode’s interface, we propose herein an effective suppression of vertical Zn growth by replacing the conventional separators with highly affordable commercially available printing paper. Based on electrochemical and structural studies followed by small punch measurements, we found that these papers comprise nanometric rigid ceramic particles that act as a physical barrier for the growth of Zn plates, preventing their penetration through the paper-based separator. As a result, the examined cells demonstrate excellent long-term performance …

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Mar 2024 • Journal of The Electrochemical Society

Specific Removal and Recovery of Bromide Ions: The Search for Stable Electrodes and Operation Modes

Izaak Cohen, Barak Shapira, Alexey Shopin, Yuval Elias, Eran Avraham, Doron Aurbach

In previous work, we introduced an elegant approach for bromide recovery from water by the introduction of a hybrid physical adsorption and capacitive deionization processes for selective removal and recovery of boron from water. In this paper, we show that the harsh environment of water contaminated with bromine-moieties adversely affects the longevity of relevant electrodes, with close to 100 consecutive work hours of bromides removal without noticeable degradation. To extend the lifespan of electrodes, we used an asymmetric CDI cell with a 1:5 positive/negative electrodes ratio in which a polarity switch between electrodes is applied every six adsorption-desorption cycles in a way that in each adsorption-desorption cycle, a different electrode of the six electrodes, functions as the positive electrode. We deduce that the polarity switch reduces oxidation and subsequent degradation of the positive electrodes …

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Mar 2024 • High Contrast Metastructures XIII, PC1289711, 2024

Extreme metaphotonics with ultra high-index chalcogenide topological insulators

Tomer Lewi

In nanophotonic, small mode volumes, narrow resonance linewidths and field enhancements, fundamentally scales with refractive index values and are key for many implementations involving light-matter interactions. Topological insulators (TI) are a class of insulating materials that host topologically protected surface states, some of which exhibit very high permittivity values. In this talk, I will present my group’s latest results on chalcogenide metaphotonics. I start by discussing Chalcogenide Bi2Te3 and Bi2Se3 TIs nanostructures. Using polarized far-field and near field Nanospectroscopy we reveal that Bi2Se3 nanobeams exhibit mid-infrared resonant modes with 2π phase shifts across the resonance. We further demonstrate that Bi2Te3 metasurfaces exhibit deep-subwavelength resonant modes utilizing their record high index value peaking at n~11. Finally we discuss how the anomalous thermo-optic effect in …

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Mar 2024 • Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XXI …, 2024

Gold nanoparticles for safe delivery of cisplatin

Yoray Sharon, Menachem Motiei, Chen Tzror-Azankot, Tamar Sadan, Rachela Popovtzer, Eli Rosenbaum

Cisplatin (CP) is the primary standard treatment for bladder cancer. Nevertheless, CP has side effects, particularly nephrotoxicity. This limits the treatment of a notable portion of advanced bladder cancer patients with cisplatin. We have developed gold nanoparticles that conjugate CP (CP-AuNPs) for safer delivery to tumors. Here, we investigated the biodistribution of the CP-AuNP conjugates in a mouse model of bladder cancer, to characterize the distinct role of CPAuNP in delivering and releasing CP in tumor and tissues. Effect of the CP-AuNPs on weight and kidney was also investigated. This study can provide insights into the potential safety of CP-AuNP for bladder cancer treatment.

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