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May 2021 • CLEO: Science and Innovations, STh4J. 4, 2021

Probing the Limits of Optical Loss in Ion-Sliced Thin-film Lithium Niobate

Amirhassan Shams-Ansari, Guanhao Huang, Lingyan He, Mikhail Churaev, Prashanta Kharel, Zelin Tan, Jeffrey Holzgrafe, Rebecca Cheng, Di Zhu, Junqiu Liu, Boris Desiatov, Mian Zhang, Tobias J Kippenberg, Marko Lončar

We measured the absorption-limited loss at telecommunication wavelengths for thin-film lithium niobate micro-ring resonators using Kerr-calibrated linear response technique. We find the average absorption loss-rate κ abs/2π to be 3.65±0.70 MHz, corresponding to a Q-factor of 55 Million.

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May 2021 • ACS applied materials & interfaces

Novel lignin-capped silver nanoparticles against multidrug-resistant bacteria

Yael N Slavin, Kristina Ivanova, Javier Hoyo, Ilana Perelshtein, Gethin Owen, Anne Haegert, Yen-Yi Lin, Stephane LeBihan, Aharon Gedanken, Urs O Häfeli, Tzanko Tzanov, Horacio Bach

The emergence of bacteria resistant to antibiotics and the resulting infections are increasingly becoming a public health issue. Multidrug-resistant (MDR) bacteria are responsible for infections leading to increased morbidity and mortality in hospitals, prolonged time of hospitalization, and additional burden to financial costs. Therefore, there is an urgent need for novel antibacterial agents that will both treat MDR infections and outsmart the bacterial evolutionary mechanisms, preventing further resistance development. In this study, a green synthesis employing nontoxic lignin as both reducing and capping agents was adopted to formulate stable and biocompatible silver–lignin nanoparticles (NPs) exhibiting antibacterial activity. The resulting silver–lignin NPs were approximately 20 nm in diameter and did not agglomerate after one year of storage at 4 °C. They were able to inhibit the growth of a panel of MDR clinical …

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May 2021 • Science Bulletin

Single-pixel imaging with high-energy electromagnetic radiation and particles

Sharon Shwartz

High-photon-energy electromagnetic radiations in the forms of X-rays and c-rays and particles such as neutrons and electrons are routinely used for various imaging and diffraction modalities with applications ranging from materials science and chemistry to biomedical imaging and industrial imaging. They provide important unique information on the structure and the functionality of the investigated samples that other methods cannot provide. However, despite the extensive efforts, there are several critical challenges that hamper further improvements in the performances of the modalities and thus limit the accessible information. Interestingly, while very different in the way high-photon-energy radiation and particles interact with the sample, imaging modalities that utilize them share similar challenges. Among the major challenges are damage to the sample when it is exposed to the probe beam and the limited resolution of the images (for electrons the resolution can be high but only for small samples). The origin of the damage is the large quanta of energy that is absorbed during the interaction between the probe and the sample. The resolution is limited since magnification and point-to-point imaging are very challenging with high energy photons and particles due to the limited available optics. For some applications, the sensitivity and the slow time response are also obstructive. Traditionally, two approaches for imaging have been utilized. In the first approach, a wide beam irradiates the sample, and a pixelated detector is mounted after the sample to measure the intensity distribution of the transmitted or scattered beam. In the second approach, a …

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May 2021 • Neuro-oncology

Loss of H3K27me3 in meningiomas

Farshad Nassiri, Justin Z Wang, Olivia Singh, Shirin Karimi, Tatyana Dalcourt, Nazanin Ijad, Neda Pirouzmand, Ho-Keung Ng, Andrea Saladino, Bianca Pollo, Francesco Dimeco, Stephen Yip, Andrew Gao, Kenneth Aldape, Gelareh Zadeh

Background There is a critical need for objective and reliable biomarkers of outcome in meningiomas beyond WHO classification. Loss of H3K27me3 has been reported as a prognostically unfavorable alteration in meningiomas. We sought to independently evaluate the reproducibility and prognostic value of H3K27me3 loss by immunohistochemistry (IHC) in a multicenter study. Methods IHC staining for H3K27me3 and analyses of whole slides from 181 meningiomas across three centers was performed. Staining was analyzed by dichotomization into loss and retained immunoreactivity, and using a 3-tiered scoring system in 151 cases with clear staining. Associations of grouping with outcome were performed using Kaplan-Meier survival estimates. Results A total of 21 of 151 tumors (13.9%) demonstrated complete loss of H3K27me3 staining in tumor with …

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May 2021 • Entropy

Uncertainty relation between detection probability and energy fluctuations

Felix Thiel, Itay Mualem, David Kessler, Eli Barkai

A classical random walker starting on a node of a finite graph will always reach any other node since the search is ergodic, namely it fully explores space, hence the arrival probability is unity. For quantum walks, destructive interference may induce effectively non-ergodic features in such search processes. Under repeated projective local measurements, made on a target state, the final detection of the system is not guaranteed since the Hilbert space is split into a bright subspace and an orthogonal dark one. Using this we find an uncertainty relation for the deviations of the detection probability from its classical counterpart, in terms of the energy fluctuations. View Full-Text

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May 2021 • ACS Applied Materials & Interfaces

Toward Efficient Synthesis of Porous All-Carbon-Based Nanocomposites for Enantiospecific Separation

Milena Perovic, Sapir Shekef Aloni, Wuyong Zhang, Yitzhak Mastai, Markus Antonietti, Martin Oschatz

Chiral separation and asymmetric synthesis and catalysis are crucial processes for obtaining enantiopure compounds, which are especially important in the pharmaceutical industry. The efficiency of the separation processes is readily increased by using porous materials as the active material can interact with a larger surface area. Silica, metal–organic frameworks, or chiral polymers are versatile porous materials that are established in chiral applications, but their instability under certain conditions in some cases requires the use of more stable porous materials such as carbons. In addition to their stability, porous carbon materials can be tailored for their ability to adsorb and catalytically activate different chemical compounds from the liquid and the gas phase. The difficulties imposed by the functionalization of carbons with chiral species were tackled in the past by carbonizing chiral ionic liquids (CILs) together with a …

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May 2021 • Journal of chemical information and modeling

Benchmarking the ability of common docking programs to correctly reproduce and score binding modes in SARS-CoV-2 protease mpro

Shani Zev, Keren Raz, Renana Schwartz, Reem Tarabeh, Prashant Kumar Gupta, Dan T Major

The coronavirus SARS-CoV-2 main protease, Mpro, is conserved among coronaviruses with no human homolog and has therefore attracted significant attention as an enzyme drug target for COVID-19. The number of studies targeting Mpro for in silico screening has grown rapidly, and it would be of great interest to know in advance how well docking methods can reproduce the correct ligand binding modes and rank these correctly. Clearly, current attempts at designing drugs targeting Mpro with the aid of computational docking would benefit from a priori knowledge of the ability of docking programs to predict correct binding modes and score these correctly. In the current work, we tested the ability of several leading docking programs, namely, Glide, DOCK, AutoDock, AutoDock Vina, FRED, and EnzyDock, to correctly identify and score the binding mode of Mpro ligands in 193 crystal structures. None of the codes …

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May 2021 • Nature communications

CRISPECTOR provides accurate estimation of genome editing translocation and off-target activity from comparative NGS data

Ido Amit, Ortal Iancu, Alona Levy-Jurgenson, Gavin Kurgan, Matthew S McNeill, Garrett R Rettig, Daniel Allen, Dor Breier, Nimrod Ben Haim, Yu Wang, Leon Anavy, Ayal Hendel, Zohar Yakhini

Controlling off-target editing activity is one of the central challenges in making CRISPR technology accurate and applicable in medical practice. Current algorithms for analyzing off-target activity do not provide statistical quantification, are not sufficiently sensitive in separating signal from noise in experiments with low editing rates, and do not address the detection of translocations. Here we present CRISPECTOR, a software tool that supports the detection and quantification of on-and off-target genome-editing activity from NGS data using paired treatment/control CRISPR experiments. In particular, CRISPECTOR facilitates the statistical analysis of NGS data from multiplex-PCR comparative experiments to detect and quantify adverse translocation events. We validate the observed results and show independent evidence of the occurrence of translocations in human cell lines, after genome editing. Our methodology is …

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Apr 2021 • Journal of Medical Engineering & Technology

Validation of a novel contact-free heart and respiratory rate monitor

Ofer Havakuk, Ben Sadeh, Ilan Merdler, Zeev Zalevsky, Javier Garcia-Monreal, Sagi Polani, Yaron Arbel

There is a growing need for remote monitoring of patients due to a lack of resources and infection control. Current systems use sensors that require constant physical contact with the user, which may result in discomfort or lack of adherence. In the present study, we evaluated the accuracy of a new contact-free system to monitor heart and respiratory rate. Study participants were measured simultaneously using two devices: a contact-free optical system that measures nano-vibrations and movements (investigational device, “Gili Pro BioSensor”) and a standard reference bed-side monitor, inclusive of an electrocardiogram and capnograph modules (Mindray®). Co-primary endpoints included HR and RR accuracy in subjects without active arrhythmias for HR, and for all study populations for RR (i.e., for subjects with and without active arrhythmias). Confirmatory secondary endpoints included HR scored continuously for …

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Apr 2021 • Journal of Laser Micro/Nanoengineering

Influence of Nanosecond Pulse Bursts at High Repetition Rates on Ablation Process.

John Linden, Sharona Cohen, Yuval Berg, Zvi Kotler, Zeev Zalevsky

Nanosecond laser pulsed ablation is a common technique for micromachining of microelectronics. Recent laser technologies use temporal shaping of single pulses to create ‘pulse bursts’ of several short consecutive pulses at several times the laser repetition rate with a reduced peak power, achieving significantly higher average powers. In this study we tested the effects of pulse bursts on ablation of multilayer PCB. We show that by implementing temporal beam shaping, we were able to increase the throughput by a factor of 40%. To gain a deeper insight of the laser mater interactions of ablation with pulse bursts, we studied the plasma emissions and monitor the process with a time resolution of several nanoseconds. These results demonstrate the importance of temporal pulse shapes for laser micromachining in the microelectronics industry.

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Apr 2021 • Nature Photonics

A wavelength-scale black phosphorus spectrometer

Shaofan Yuan, Doron Naveh, Kenji Watanabe, Takashi Taniguchi, Fengnian Xia

On-chip spectrometers with compact footprints are being extensively investigated owing to their promising future in critical applications such as sensing, surveillance and spectral imaging. Most existing miniaturized spectrometers use large arrays of photodetection elements to capture different spectral components of incident light, from which its spectrum is reconstructed. Here, we demonstrate a mid-infrared spectrometer in the 2–9 µm spectral range, utilizing a single tunable black phosphorus photodetector with an active area footprint of only 9× 16 µm 2, along with a unique spectral learning procedure. Such a single-detector spectrometer has a compact size at the scale of the operational wavelength. Leveraging the wavelength and bias-dependent responsivity matrix learned from the spectra of a tunable blackbody source, we reconstruct unknown spectra from their corresponding photoresponse vectors. Enabled …

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Apr 2021 • Nano-Structures & Nano-Objects

Biocompatible N-doped carbon dots for the eradication of methicillin-resistant S. aureus (MRSA) and sensitive analysis for europium (III)

Moorthy Maruthapandi, Poushali Das, Arumugam Saravanan, Michal Natan, Ehud Banin, Sriram Kannan, Shulamit Michaeli, John HT Luong, Aharon Gedanken

Plant leaves have more attracted in the preparation of carbon dots (CDs) owing to natural phytochemicals. Herein, we performed a one-pot hydrothermal process for the synthesis of Nitrogen doped CDs (N@ CDs) from glossy heart-shaped Piper betel leaves (P. betel). The prepared N@ CDs were effectively applied for the eradication of E. coli, S. aureus, and methicillin-resistant S. aureus (MRSA). The N@ CDs were also used as a sensor for lanthanides detection with notable selectivity for Eu 3+. The results revealed that the water-soluble N@ CDs displayed narrow size particle distribution with a mean diameter of 2.6 nm. The bright fluorescence was estimated to be at λ ex: 350 with λ em: 430 nm. The functional groups on N@ CDs were confirmed by FTIR and XPS. The antimicrobial effect of N@ CDs was concentration-dependent and effectively against E. coli and S. aureus at 1000 μ g/mL. The antibacterial …

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Apr 2021 • Batteries & Supercaps

Fluorination of Ni‐Rich Lithium‐Ion Battery Cathode Materials by Fluorine Gas: Chemistry, Characterization, and Electrochemical Performance in Full‐cells

Ulf Breddemann, Johannes Sicklinger, Florian Schipper, Victoria Davis, Anna Fischer, Korbinian Huber, Evan M Erickson, Michael Daub, Anke Hoffmann, Christoph Erk, Boris Markovsky, Doron Aurbach, Hubert A Gasteiger, Ingo Krossing

The mild fluorination of Ni‐rich NCM CAMs (NCM=nickel‐cobalt‐manganese oxide; CAM=cathode active material) with a few hundred mbar of elementary fluorine gas (F2) at room temperature was systematically studied. The resulting fluorinated CAMs were fully analyzed and compared to the pristine ones. Fluorination at room temperature converts part of the soluble basic species on the CAM‐surface into a protecting thin and amorphous LiF film. No formation of a metal fluoride other than LiF was detected. SEM images revealed a smoothened CAM surface upon fluorination, possibly due to the LiF film formation. Apparently due to this protecting, but insulating LiF‐film, the fluorinated material has a reduced electrical conductivity in comparison to the pristine material. Yet, all fluorinated Ni‐rich NCM CAMs showed a considerably higher press density than the pristine material, which in addition increased with higher …

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Apr 2021 • Advanced Functional Materials

Porphyrin aerogel catalysts for oxygen reduction reaction in anion‐exchange membrane fuel cells

Noam Zion, John C Douglin, David A Cullen, Piotr Zelenay, Dario R Dekel, Lior Elbaz

Platinum group metal (PGM)‐free catalysts for oxygen reduction reaction have shown high oxygen reduction reaction activity in alkaline media. In order to further increase the power density of anion‐exchange membrane fuel cells (AEMFCs), PGM‐free catalysts need to have a high site density to reach high current densities. Herein, synthesis, characterization, and utilization of heat‐treated iron porphyrin aerogels are reported as cathode catalysts in AEMFCs. The heat treatment effect is thoroughly studied and characterized using several techniques, and the best performing aerogel is studied in AEMFC, showing excellent performance, reaching a peak power density of 580 mW cm−2 and a limiting current density of as high as 2.0 A cm−2, which can be considered the state‐of‐the‐art for PGM‐free based AEMFCs.

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Apr 2021 • Immunologic Research

Exploring genetic defects in adults who were clinically diagnosed as severe combined immune deficiency during infancy

Ido Somekh, Atar Lev, Ortal Barel, Yu Nee Lee, Ayal Hendel, Amos J Simon, Raz Somech

Genetic diagnostic tools including whole-exome sequencing (WES) have advanced our understanding in human diseases and become common practice in diagnosing patients with suspected primary immune deficiencies. Establishing a genetic diagnosis is of paramount importance for tailoring adequate therapeutic regimens, including identifying the need for hematopoietic stem cell transplantation (HSCT) and genetic-based therapies. Here, we genetically studied two adult patients who were clinically diagnosed during infancy with severe combined immune deficiency (SCID). Two unrelated patients, both of consanguineous kindred, underwent WES in adulthood, 2 decades after their initial clinical manifestations. Upon clinical presentation, immunological workup was performed, which led to a diagnosis of SCID. The patients presented during infancy with failure to thrive, generalized erythematous rash …

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Apr 2021 • Leukemia

RNA editing contributes to epitranscriptome diversity in chronic lymphocytic leukemia

Franz J Gassner, Nadja Zaborsky, Ilana Buchumenski, Erez Y Levanon, Matthias Gatterbauer, Maria Schubert, Stefanie Rauscher, Daniel Hebenstreit, Ferran Nadeu, Elias Campo, Alexander Egle, Richard Greil, Roland Geisberger

RNA editing—primarily conversion of adenosine to inosine (A> I)—is a widespread posttranscriptional mechanism, mediated by Adenosine Deaminases acting on RNA (ADAR) enzymes to alter the RNA sequence of primary transcripts. Hence, in addition to somatic mutations and alternative RNA splicing, RNA editing can be a further source for recoding events. Although RNA editing has been detected in many solid cancers and normal tissue, RNA editing in chronic lymphocytic leukemia (CLL) has not been addressed so far. We determined global RNA editing and recurrent, recoding RNA editing events from matched RNA-sequencing and whole exome sequencing data in CLL samples from 45 untreated patients. RNA editing was verified in a validation cohort of 98 CLL patients and revealed substantially altered RNA editing profiles in CLL compared with normal B cells. We further found that RNA editing patterns …

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Apr 2021 • Microporous and Mesoporous Materials

Physicochemical evaluation of the effect of natural zeolite modification with didodecyldimethylammonium bromide on the adsorption of Bisphenol-A and Propranolol Hydrochloride

Akmaral B Rakhym, Gulziya A Seilkhanova, Yitzhak Mastai

Wastewater pollution by organic anions is of great interest. Surfactant-modified zeolites exhibit high adsorption of both organic and inorganic toxicants. Here, bisphenol-A and propranolol hydrochloride were adsorbed on natural zeolite modified with the cationic surfactant didodecyldimethylammonium bromide with and without pretreatment of the zeolite with NaCl and HCl. Detailed physicochemical analysis shows chemisorption, electrostatic and hydrophobic interactions with the surfactant and bisphenol-A, and in the case of propranolol, also physisorption.

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Apr 2021 • arXiv preprint arXiv:2104.06232

Driving quantum systems with repeated conditional measurements

Quancheng Liu, Klaus Ziegler, David A Kessler, Eli Barkai

We investigate the effect of conditional null measurements on a quantum system and find a rich variety of behaviors. Specifically, quantum dynamics with a time independent in a finite dimensional Hilbert space are considered with repeated strong null measurements of a specified state. We discuss four generic behaviors that emerge in these monitored systems. The first arises in systems without symmetry, along with their associated degeneracies in the energy spectrum, and hence in the absence of dark states as well. In this case, a unique final state can be found which is determined by the largest eigenvalue of the survival operator, the non-unitary operator encoding both the unitary evolution between measurements and the measurement itself. For a three-level system, this is similar to the well known shelving effect. Secondly, for systems with built-in symmetry and correspondingly a degenerate energy spectrum, the null measurements dynamically select the degenerate energy levels, while the non-degenerate levels are effectively wiped out. Thirdly, in the absence of dark states, and for specific choices of parameters, two or more eigenvalues of the survival operator match in magnitude, and this leads to an oscillatory behavior controlled by the measurement rate and not solely by the energy levels. Finally, when the control parameters are tuned, such that the eigenvalues of the survival operator all coalesce to zero, one has exceptional points that corresponds to situations that violate the null measurement condition, making the conditional measurement process impossible.

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Apr 2021 • IEEE Photonics Journal

Comment on “Rapid Image Reconstruction of Structured Illumination Microscopy Directly in the Spatial Domain” and More About Point Spread Function Shaping for Enhanced Imaging …

Dror Fixler, Zeev Zalevsky

During the past several decades, a variety of imaging modalities in fluorescence microscopy have emerged as powerful tools for probing the spatial and temporal dimensions in fixed and living cells and tissues to uncover structural and dynamic information. Recently, our journal accepted a paper in this topic, and we received comments. We found it as opportunity to discuss this important topic for additional angles. We believe that this discussion will be interesting and helpful to the whole community.

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Apr 2021 • Polymers for Advanced Technologies

Layer by layer controlled synthesis at room temperature of tri‐modal (MRI, fluorescence and CT) core/shell superparamagnetic IO/human serum albumin nanoparticles for diagnostic …

Sayan Ganguly, Igor Grinberg, Shlomo Margel

Apr 2021 • OSA Continuum

Ultra-fast remote photoacoustic imaging with a non-scanning speckle-based setup

Matan Benyamin, Hadar Genish, Ran Califa, Nisan Ozana, Benjamin Lengenfelder, Florian Klämpfl, Zeev Zalevsky

A method for fast non-scanning remote photoacoustic imaging is presented and experimentally demonstrated. The approach is based on speckle contrast measurement, proceeding the previously developed method for speckle contrast based photoacoustic detection. This previously developed method is now presented without the need for raster scanning of the sample, an advantage rarely found in optical photoacoustic detection, and offers 50 times faster as well as a simpler remote photoacoustic scheme in respect to interferometric available solutions.

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