Dec 2021 • Cellulose
Lama Jabareen, Moorthy Maruthapandi, Arumugam Saravanan, Aharon Gedanken
Lignocellulose biomass effectively produces chemicals and fuels, which are of importance for the establishment of a sustainable society. The conversion of cellulose, the main component of the biomass, into significant precursors that can be further converted to different chemicals or fuels under gentle conditions is a promising route. Organic acids such as acetic, glycolic and formic acid are significant examples. A novel method to produce important platform chemicals from micro-crystalline cellulose (MCC) was developed. MCC was degraded as a result of oxidation with potassium chlorate by microwave radiation in a one-pot procedure. Efficient reaction conditions such as short reaction time and full conversion of cellulose were identified. The reaction products were analyzed by 1H and 13C NMR, XPS, TGA and XRD.
Show moreDec 2021 • Advanced Functional Materials
Arka Saha, Netanel Shpigel, Nicole Leifer, Sarah Taragin, Tali Sharabani, Hagit Aviv, Ilana Perelshtein, Gilbert Daniel Nessim, Malachi Noked, Yury Gogotsi
MXenes are a large class of 2D materials that consist of few‐atoms‐thick layers of transition metal carbides, nitrides, or carbonitrides. The surface functionalization of MXenes has immense implications for their physical, chemical, and electronic properties. However, solution‐phase surface functionalization often leads to structural degradation of the MXene electrodes. Here, a non‐conventional, single‐step atomic surface reduction (ASR) technique is adopted for the surface functionalization of MXene (Ti3C2Tx) in an atomic layer deposition reactor using trimethyl aluminum as a volatile reducing precursor. The chemical nature of the modified surface is characterized by X‐ray photoelectron spectroscopy and nuclear magnetic resonance techniques. The electrochemical properties of the surface‐modified MXene are evaluated in acidic and neutral aqueous electrolyte solutions, as well as in conventional Li‐ion and …
Show moreDec 2021 • ACS Applied Materials & Interfaces
Samuel S Hardisty, Shira Frank, Melina Zysler, Reut Yemini, Anya Muzikansky, Malachi Noked, David Zitoun
Dec 2021 • Virology journal
Coral Orel Haddad, Inna Kalt, Yehuda Shovman, Lei Xia, Yehuda Schlesinger, Ronit Sarid, Oren Parnas
Kaposi’s sarcoma-associated herpesvirus (KSHV) is a transforming gammaherpesvirus. Like other herpesviruses, KSHV infection is for life long and there is no treatment that can cure patients from the virus. In addition, there is an urgent need to target viral genes to study their role during the infection cycle. The CRISPR-Cas9 technology offers a means to target viral genomes and thus may offer a novel strategy for viral cure as well as for better understanding of the infection process. We evaluated the suitability of this platform for the targeting of KSHV. We have used the recombinat KSHV BAC16 genome, which contains an expression cassette encoding hygromycin-resistance and a GFP marker gene. Three genes were targeted: gfp, which serves as a marker for infection; orf45 encoding a lytic viral protein; and orf73, encoding LANA which is crucial for latent infection. The fraction of cells expressing GFP, viral DNA levels and LANA expression were monitored and viral genomes were sequenced. We found that KSHV episomes can be targeted by CRISPR-Cas9. Interestingly, the quantity of KSHV DNA declined, even when target sites were not functionally important for latency. In addition, we show that antibiotic selection, used to maintain infection, interferes with the outcome of targeting. Our study provides insights into the use of this fundamental approach for the study and manipulation of KSHV. It provides guidelines for the targeting CRISPR-Cas9 to the viral genome and for outcomes interpretation.
Show moreDec 2021 • Small
Tali Sharabani, Sarah Taragin, Ilana Perelshtein, Malachi Noked, Ayan Mukherjee
To mitigate the associated challenges of instability and capacity improvement in Na3V2(PO4)2F3 (NVPF), rationally designed uniformly distributed hollow spherical NVPF and coating the surface of NVPF with ultrathin (≈2 nm) amorphous TiO2 by atomic layer deposition is demonstrated. The coating facilitates higher mobility of the ion through the cathode electrolyte interphase (CEI) and enables higher capacity during cycling. The TiO2@NVPF exhibit discharge capacity of >120 mAhg−1, even at 1C rates, and show lower irreversible capacity in the first cycle. Further, nearly 100% capacity retention after rate performance in high current densities and 99.9% coulombic efficiency after prolonged cycling in high current density is reported. The improved performance in TiO2@NVPF is ascribed to the passivation behavior of TiO2 coating which protects the surface of NVPF from volume expansion, significantly less …
Show moreDec 2021 • Journal of Chemical Theory and Computation
Shani Zev, Prashant Kumar Gupta, Efrat Pahima, Dan Thomas Major
Carbocations play key roles in classical organic reactions and have also been implicated in several enzyme families. A hallmark of carbocation chemistry is multitudes of competing reaction pathways, and to be able to distinguish between pathways with quantum chemical calculations, it is necessary to approach chemical accuracy for relative energies between carbocations. Here, we present an extensive study of the performance of selected density functional theory (DFT) methods in describing the thermochemistry and kinetics of carbocations and their corresponding neutral alkenes both in the gas-phase and within a hybrid quantum mechanics-molecular mechanics (QM/MM) framework. The density functionals are benchmarked against accurate ab initio methods such as CBS-QB3 and DLPNO-CCSD(T). Based on the findings in the gas-phase calculations of carbocations and alkenes, the best functionals are …
Show moreDec 2021 • Materials Science and Engineering: C
Aleksandra Ivanova, Kristina Ivanova, Ilana Perelshtein, Aharon Gedanken, Katerina Todorova, Rositsa Milcheva, Petar Dimitrov, Teodora Popova, Tzanko Tzanov
Catheter-associated urinary tract infections (CAUTIs), caused by biofilms, are the most frequent health-care associated infections. Novel antibiofilm coatings are needed to increase the urinary catheters' life-span, decrease the prevalence of CAUTIs and reduce the development of antimicrobial resistance. Herein, antibacterial zinc oxide nanoparticles (ZnO NPs) were decorated with a biofilm matrix-degrading enzyme amylase (AM) and simultaneously deposited onto silicone urinary catheters in a one-step sonochemical process. The obtained nano-enabled coatings inhibited the biofilm formation of Escherichia coli and Staphylococcus aureus by 80% and 60%, respectively, for up to 7 days in vitro in a model of catheterized bladder with recirculation of artificial urine due to the complementary mode of antibacterial and antibiofilm action provided by the NPs and the enzyme. Over this period, the coatings did not induce …
Show moreDec 2021 • Optics Express
Leon Bello, Yoad Michael, Michael Rosenbluh, Eliahu Cohen, Avi Pe’er
In their seminal paper, Caves and Schumaker presented a new formalism for quantum optics, intended to serve as a building block for describing two-photon processes, in terms of new, generalized qudratures. The important, revolutionary concept in their formalism was that it was fundamentally two-mode, i.e. the related observables could not be attributed to any single one of the comprising modes, but rather to a generalized complex quadrature that could only be attributed to both of them. Here, we propose a subtle, but fundamentally meaningful modification to their important work. Unlike the above proposal, we deliberately choose a frequency-agnostic definition of the two-mode quadrature, that we motivate on physical grounds. This simple modification has far-reaching implications to the formalism – the real and imaginary parts of the quadratures now coincide with the famous EPR variables, and our two-mode …
Show moreDec 2021 • Genome Research
Ilana Buchumenski, Shalom Hillel Roth, Eli Kopel, Efrat Katsman, Ariel Feiglin, Erez Y Levanon, Eli Eisenberg
Base editors are dedicated engineered deaminases that enable directed conversion of specific bases in the genome or transcriptome in a precise and efficient manner, and hold promise for correcting pathogenic mutations. A major concern limiting application of this powerful approach is the issue of off-target edits. Several recent studies have shown substantial off-target RNA activity induced by base editors and demonstrated that off-target mutations may be suppressed by improved deaminases versions or optimized guide RNAs. Here, we describe a new class of off-target events that are invisible to the established methods for detection of genomic variations and were thus far overlooked. We show that nonspecific, seemingly stochastic, off-target events affect a large number of sites throughout the genome or the transcriptome, and account for the majority of off-target activity. We develop and employ a different …
Show moreDec 2021 • Biophysical Reports
Simon Sehayek, Xiyu Yi, Shimon Weiss, Paul W Wiseman
We present a fluorescence fluctuation image correlation analysis method that can rapidly and simultaneously measure the diffusion coefficient, photoblinking rates, and fraction of diffusing particles of fluorescent molecules in cells. Unlike other image correlation techniques, we demonstrated that our method could be applied irrespective of a nonuniformly distributed, immobile blinking fluorophore population. This allows us to measure blinking and transport dynamics in complex cell morphologies, a benefit for a range of super-resolution fluorescence imaging approaches that rely on probe emission blinking. Furthermore, we showed that our technique could be applied without directly accounting for photobleaching. We successfully employed our technique on several simulations with realistic EMCCD noise and photobleaching models, as well as on Dronpa-C12-labeled β-actin in living NIH/3T3 and HeLa cells. We …
Show moreDec 2021 • ACS Applied Materials & Interfaces
Ariel Friedman, Michal Mizrahi, Naomi Levy, Noam Zion, Michael Zachman, Lior Elbaz
The development of precious group metal-free (PGM-free) catalysts for the oxygen reduction reaction is considered as the main thrust for the cost reduction of fuel cell technologies and their mass production. Within the PGM-free category, molecular catalysts offer an advantage over other heat-treated PGM-free catalysts owing to their well-defined structure, which enables further design of more active, selective, and durable catalysts. Even though non-heat-treated molecular catalysts with exceptional performance have been reported in the past, they were rarely tested in a fuel cell. Herein, we report on a molecular catalyst under alkaline conditions: fluorinated iron phthalocyanine (FeFPc) supported on cheap and commercially available high-surface area carbon─BP2000 (FeFPc@BP2000). It exhibits the highest activity ever reported for molecular catalysts under alkaline conditions in half-cells and fuel cells.
Show moreDec 2021 • Desalination 520, 115336, 2021
Xiumei Ma, Wei Alex Wang, Lupeng Zhang, Qinghao Wu, Shanfu Lu, Doron Aurbach, Yan Xiang
Dec 2021 • Energy Technology
Anna Kitayev, Melina Zysler, Samuel Hardisty, Miles Page, Ervin Tal-Gutelmacher, David Zitoun
The oxygen reduction reaction (ORR) is a key process in anion exchange membrane fuel cells. The alkaline conditions should allow silver‐based cost‐efficient catalysts to replace platinum group metal materials. However, Ag electrochemical stability or lack of stability in alkaline medium is still to be demonstrated. Herein, Ag catalyst nanoparticles (NPs) are characterized by identical location transmission electron microscopy and X‐ray photoelectron spectroscopy after electrochemical cycling, revealing the losses of activity and surface. Herein, a facile method for enhancing the chemical stability of Ag catalysts in an alkaline environment by depositing a protective polydopamine (PDA) coating is reported. It is enhanced via crosslinking with polyethyleneimine (PEI), on the surface of Ag NPs. The enhanced electrochemical stability of Ag PDA–PEI nanocatalyst via the analysis of ORR polarization curves during …
Show moreDec 2021 • Desalination 520, 115336, 2021
Xiumei Ma, Wei Alex Wang, Lupeng Zhang, Qinghao Wu, Shanfu Lu, Doron Aurbach, Yan Xiang
Desalination is a critical process to resolve the crisis of insufficient freshwater resources. Among desalination technologies, electrochemical electrode deionization (EEDI) has attracted wide attention because of the advantages in low cost, no secondary pollution, and low energy consumption etc. Electrode materials are the critical factors for determining the performance of EEDI. However, the traditional EEDI with carbon electrode (capacitive deionization, CDI) often showed inefficient desalination capacity, charge efficiency, cycle stability as well as ions selectivity due to the anode oxidation. Therefore, the development of anions-capture materials is crucial for the development of EEDI devices. In this review, the anions-capture materials are classified into four categories according to their capture mechanisms: (i) Electrosorption materials, mainly including conventional and modified carbon materials; (ii) conversion …
Show moreDec 2021 • Optics Express
Leon Bello, Yoad Michael, Michael Rosenbluh, Eliahu Cohen, Avi Pe’er
In their seminal paper, Caves and Schumaker presented a new formalism for quantum optics, intended to serve as a building block for describing two-photon processes, in terms of new, generalized qudratures. The important, revolutionary concept in their formalism was that it was fundamentally two-mode, ie the related observables could not be attributed to any single one of the comprising modes, but rather to a generalized complex quadrature that could only be attributed to both of them. Here, we propose a subtle, but fundamentally meaningful modification to their important work. Unlike the above proposal, we deliberately choose a frequency-agnostic definition of the two-mode quadrature, that we motivate on physical grounds. This simple modification has far-reaching implications to the formalism–the real and imaginary parts of the quadratures now coincide with the famous EPR variables, and our two-mode …
Show moreDec 2021 • Big Data and Cognitive Computing
Oz Pirvandy, Moti Fridman, Gur Yaari
A sports multi-bet is a bet on the results of a set of N games. One type of multi-bet offered by the Israeli government is WINNER 16, where participants guess the results of a set of 16 soccer games. The prizes in WINNER 16 are determined by the accumulated profit in previous rounds, and are split among all winning forms. When the reward increases beyond a certain threshold, a profitable strategy can be devised. Here, we present a machine-learning algorithm scheme to play WINNER 16. Our proposed algorithm is marginally profitable on average in a range of hyper-parameters, indicating inefficiencies in this game. To make a better prize-pricing mechanism we suggest a generalization of the single-bet approach. We studied the expected profit and risk of WINNER 16 after applying our suggestion. Our proposal can make the game more fair and more appealing without reducing the profitability. View Full-Text
Show moreDec 2021 • ACS Applied Materials & Interfaces
Samuel S Hardisty, Shira Frank, Melina Zysler, Reut Yemini, Anya Muzikansky, Malachi Noked, David Zitoun
Catalyst poisoning is a prominent issue, reducing the lifetime of catalysts and increasing the costs of the processes that rely on them. The electrocatalysts that enable green energy conversion and storage, such as proton exchange membrane fuel cells and hydrogen bromine redox flow batteries, also suffer from this issue, hindering their utilization. Current solutions to protect electrocatalysts from harmful species fall short of effective selectivity without inhibiting the required reactions. This article describes the protection of a standard 50% Pt/C catalyst with a V2O5 coating through atomic layer deposition (ALD). The ALD selectively deposited V2O5 on the Pt, which enhanced hydrogen transport to the Pt surface and resulted in a higher mass activity in alkaline electrolytes. Cyclic voltammetry and X-ray photoelectron spectroscopy showed that the Pt was protected by the coating in the HBr/Br2 electrolyte which dissolved …
Show moreDec 2021 • arXiv preprint arXiv:2112.14989
Danveer Singh, Michal Poplinger, Avraham Twitto, Rafi Snitkoff, Pilkhaz Nanikashvili, Ori Azolay, Adi Levi, Chen Stern, Gili Cohen Taguri, Asaf Albo, Doron Naveh, Tomer Lewi
Applying direct growth and deposition of optical surfaces holds great promise for the advancement of future nanophotonic technologies. Here, we report on a chemical vapor deposition (CVD) technique for depositing amorphous selenium (a-Se) spheres by desorption of selenium from Bi2Se3 and re-adsorption on the substrate. We utilize this process to grow scalable, large area Se spheres on several substrates and characterize their Mie-resonant response in the mid-infrared (MIR) spectral range. We demonstrate size-tunable Mie resonances spanning the 2-16 um spectral range, for single isolated resonators and large area ensembles, respectively. We further demonstrate strong absorption dips of up to 90% in ensembles of particles in a broad MIR range. Finally, we show that ultra-high-Q resonances arise in the case where Se Mie-resonators are coupled to low-loss epsilon-near-zero (ENZ) substrates. These findings demonstrate the enabling potential of amorphous Selenium as a versatile and tunable nanophotonic material that may open up avenues for on-chip MIR spectroscopy, chemical sensing, spectral imaging and large area metasurface fabrication.
Show moreDec 2021 • ACS Applied Materials & Interfaces
Ariel Friedman, Michal Mizrahi, Naomi Levy, Noam Zion, Michael Zachman, Lior Elbaz
The development of precious group metal-free (PGM-free) catalysts for the oxygen reduction reaction is considered as the main thrust for the cost reduction of fuel cell technologies and their mass production. Within the PGM-free category, molecular catalysts offer an advantage over other heat-treated PGM-free catalysts owing to their well-defined structure, which enables further design of more active, selective, and durable catalysts. Even though non-heat-treated molecular catalysts with exceptional performance have been reported in the past, they were rarely tested in a fuel cell. Herein, we report on a molecular catalyst under alkaline conditions: fluorinated iron phthalocyanine (FeFPc) supported on cheap and commercially available high-surface area carbon─BP2000 (FeFPc@BP2000). It exhibits the highest activity ever reported for molecular catalysts under alkaline conditions in half-cells and fuel cells.
Show moreDec 2021 • Journal of Chemical Theory and Computation
Shani Zev, Prashant Kumar Gupta, Efrat Pahima, Dan Thomas Major
Carbocations play key roles in classical organic reactions and have also been implicated in several enzyme families. A hallmark of carbocation chemistry is multitudes of competing reaction pathways, and to be able to distinguish between pathways with quantum chemical calculations, it is necessary to approach chemical accuracy for relative energies between carbocations. Here, we present an extensive study of the performance of selected density functional theory (DFT) methods in describing the thermochemistry and kinetics of carbocations and their corresponding neutral alkenes both in the gas-phase and within a hybrid quantum mechanics-molecular mechanics (QM/MM) framework. The density functionals are benchmarked against accurate ab initio methods such as CBS-QB3 and DLPNO-CCSD(T). Based on the findings in the gas-phase calculations of carbocations and alkenes, the best functionals are …
Show moreDec 2021 • Journal of translational medicine
Indrani Datta, Houtan Noushmehr, Chaya Brodie, Laila M Poisson
Clinically relevant glioma subtypes, such as the glioma-CpG island methylator phenotype (G-CIMP), have been defined by epigenetics. In this study, the role of long non-coding RNAs in association with the poor-prognosis G-CMIP-low phenotype and the good-prognosis G-CMIP-high phenotype was investigated. Functional associations of lncRNAs with mRNAs and miRNAs were examined to hypothesize influencing factors of the aggressive phenotype. RNA-seq data on 250 samples from TCGA’s Pan-Glioma study, quantified for lncRNA and mRNAs (GENCODE v28), were analyzed for differential expression between G-CIMP-low and G-CIMP-high phenotypes. Functional interpretation of the differential lncRNAs was performed by Ingenuity Pathway Analysis. Spearman rank order correlation estimates between lncRNA, miRNA, and mRNA nominated differential lncRNA with a likely miRNA sponge function. We identified 4371 differentially expressed features (mRNA = 3705; lncRNA = 666; FDR ≤ 5%). From these, the protein-coding gene TP53 was identified as an upstream regulator of differential lncRNAs PANDAR and PVT1 (p = 0.0237) and enrichment was detected in the “development of carcinoma” (p = 0.0176). Two lncRNAs (HCG11, PART1) were positively correlated with 342 mRNAs, and their correlation estimates diminish after adjusting for either of the target miRNAs: hsa-miR-490-3p, hsa-miR-129-5p. This suggests a likely sponge function for HCG11 and PART1. These findings identify differential lncRNAs with oncogenic features that are associated with G-CIMP phenotypes. Further investigation with controlled experiments …
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