BINA

Enormous potential loss and sluggish kinetics of the oxygen evolution reaction (OER) limit the practical implementation of water electrolyser systems. We attempt to address these technical challenges through the synthesis of cobalt–chromium-layered double hydroxide nanosheets (CoCr LDH) on oxidized-carbon nanotube (O-CNT) backbones as efficient OER electrocatalysts. Microscopic and elemental distribution analysis suggests that interconnected sheets of CoCr LDH masks over O-CNTs. We tested various compositions of the CoCr LDH_O-CNT hybrid (by varying the molar ratios of Co and Cr) along with the weight adjustment between CoCr LDH and O-CNTs to obtain an optimal OER activity. Due to the synergistic effect, the CoCr-LDH(3:1)_O-CNT (2:1) exhibits the lowest overpotential of 290 mV at 10 mA cm–2 with a corresponding smaller Tafel slope of 42 mV dec–1, which outperforms the other tested …

This study aims to investigate the effects of a novel ZnCuO nanoparticle coating for dental implants—versus those of conventional titanium surfaces—on bacteria and host cells. A multispecies biofilm composed of Streptococcus sanguinis, Actinomyces naeslundii, Porphyromonas gingivalis, and Fusobacterium nucleatum was grown for 14 days on various titanium discs: machined, sandblasted, sandblasted and acid-etched (SLA), ZnCuO-coated, and hydroxyapatite discs. Bacterial species were quantified with qPCR, and their viability was examined via confocal microscopy. Osteoblast-like and macrophage-like cells grown on the various discs for 48 h were examined for proliferation using an XTT assay, and for activity using ALP and TNF-α assays. The CSLM revealed more dead bacteria in biofilms grown on titanium than on hydroxyapatite, and less on sandblasted than on machined and ZnCuO-coated surfaces, with the latter showing a significant decrease in all four biofilm species. The osteoblast-like cells showed increased proliferation on all of the titanium surfaces, with higher activity on the ZnCuO-coated and sandblasted discs. The macrophage-like cells showed higher proliferation on the hydroxyapatite and sandblasted discs, and lower activity on the SLA and ZnCuO-coated discs. The ZnCuO-coated titanium has anti-biofilm characteristics with desired effects on host cells, thus representing a promising candidate in the complex battle against peri-implantitis.

We study the polarization dynamics of ultrafast solitons in mode-locked fiber lasers. We found that when a stable soliton is generated, its state-of-polarization shifts toward a stable state, and when the soliton is generated with excess power levels it experiences relaxation oscillations in its intensity and timing. On the other hand, when a soliton is generated in an unstable state-of-polarization, it either decays in intensity until it disappears, or its temporal width decreases until it explodes into several solitons, and then it disappears. All our results are supported by both experimental measurements and calculated results. For numerically modeling the dynamics of ultrafast solitons we resort to a non-Lagrangian approach for simulating coupled complex Ginzburg-Landau equations for the two components of the electric wave vector. Here we present the numerical code and results and explain in details how we obtained them.

We spontaneously generated idler and signal beams with four-wave mixing process. Next, we measured with a time-lens their internal structure and found that the statistics of the different peaks and the separation between the peaks follow stochastic process. This is essential first step before checking the correlation between the beams and the entanglement of the generated photons.

The study of recurrences and revivals in quantum systems has attracted a great deal of interest because of its importance in the control of quantum systems and its potential use in developing new technologies. In this paper, we introduce a protocol to induce full-state revivals in a huge class of quantum walks on a d-dimensional lattice governed by a c-dimensional coin system. The protocol requires two repeated interventions in the coin degree of freedom. We also present a characterization of the walks that admit such a protocol. Moreover, we modify the quantity known as the Pólya number, typically used in the study of recurrences in classical random walks and quantum walks, to create a witness of the first revival of the walk.

Rechargeable Li metal batteries (LMBs) have attracted wide attention as promising candidates for the next generation of energy-storage systems. However, limited Coulombic efficiency and unregulated dendrite growth restrict its application. Here, we report a kind of electrolyte by introducing fluorinated aromatic diluents into high-concentration electrolytes (HCEs). Unlike other localized HCEs, the fluorinated aromatic diluents pairing with anions promote the formation of a homogeneous and robust solid–electrolyte interphase (SEI), which endows Li metal with an ultrahigh Coulombic efficiency of ∼99.8%. The Li||LiNi0.8Co0.1Mn0.1O2 battery holds a capacity retention of >80% over 260 cycles even with a thin Li anode (20 μm) and a high cathode loading (3.5 mAh cm–2). A 1.8 Ah Li||NMC811 pouch cell with a lean electrolyte delivers an energy density of 340 Wh kg–1 and a stable cycling life over 200 cycles. The …

We study the aberrations of four-wave mixing-based time-lenses resulting from the cross-phase modulations of the pump wave. These temporal aberrations have no spatial equivalent and are important when imaging weak signals with strong pump waves.In this work we show that as the pump power increases the cross-phase modulations of the pump are responsible for shifting, defocusing, and imposing temporal coma aberrations on the image.

Optical imaging (OI) has become the most used alternative imaging tool for pre-clinical studies. Among all molecular imaging modalities, fluorescence optical imaging is central thanks to its high sensitivity, the numerous molecular probes available (either endogenous or exogenous) and its ability to simultaneously image multiple biomarkers or biological processes at various spatio-temporal scales. Especially, fluorescence lifetime imaging (FLI) has become an increasingly popular method, as it provides unique insights into the cellular micro-environment by non-invasively examining numerous intracellular parameters such as metabolic status, reactive oxygen species and intracellular pH. Moreover, FLI’s exploitation of native fluorescent signatures has been extensively investigated for enhanced diagnostic of numerous pathologies. However, to perform such measurements in intact, live specimen, it is required to …

Coral reefs are in global decline due to climate change and anthropogenic influences (Hughes et al., 2013). Near coastal cities or other densely populated areas, coral reefs face a range of additional challenges. While considerable progress has been made in understanding coral responses to acute individual stressors (Dominoni et al., 2020), the impacts of chronic exposure to varying combinations of sensory pollutants are largely unknown. To investigate the impacts of urban proximity on corals, we conducted a year‐long in‐natura study ‐ incorporating sampling at diel, monthly, and seasonal time points – in which we compared corals from an Urban area to corals from a proximal Non‐Urban area. Here we reveal that despite appearing relatively healthy, natural biorhythms and environmental sensory systems were extensively disturbed in corals from the Urban environment. Transcriptomic data indicated poor …

Frequency-domain (FD) fluorometry is a widely utilized tool to probe unique features of complex biological structures, which may serve medical diagnostic purposes. The conventional data analysis approaches used today to extract the fluorescence intensity or fluorescence anisotropy (FA) decay data suffer from several drawbacks and are inherently limited by the characteristics and complexity of the decay models. This paper presents the squared distance (D^2) technique, which categorized samples based on the direct frequency response data (FRD) of the FA decay. As such, it improves the classification ability of the FD measurements of the FA decay as it avoids any distortion that results from the challenged translation into time domain data. This paper discusses the potential use of the D^2 approach to classify biological systems. Mathematical formulation of D^2 technique adjusted to the FRD of the FA decay is …

A promising venue for hybrid quantum computation involves the strong coupling between impurity spins and superconducting circuits. This coupling can be controlled and enhanced by preparing superconducting resonators in nonclassical states, such as squeezed states. In this work, we theoretically study the effects of these states on the coherence properties of the spin. We develop an analytic approach based on the Schrieffer-Wolff transformation that allows us to quantitatively predict the dynamics of the spin, and we numerically confirm its validity. We find that squeezing can enhance the coupling between the resonator and the spin. However, at the same time, it amplifies the photon noise and enhances the spin decoherence. Our work demonstrates a major impediment in using squeezing to reach the strong-coupling limit.

Metastatic breast cancer (MBC) remains incurable due to inevitable development of therapeutic resistance. Although tumor cell intrinsic mechanisms of resistance in MBC are beginning to be elucidated by bulk sequencing studies, the roles of the tumor microenvironment and intratumor heterogeneity in therapeutic resistance remain underexplored due to both technological barriers and limited availability of samples. To comprehensively capture these characteristics we have adapted a research biopsy protocol to collect tissue for an array of single-cell and spatio-molecular assays whose performance we have optimized for MBC, including single-cell and single-nucleus RNA sequencing, Slide-Seq, Multiplexed Error-Robust FISH (MERFISH), Expansion Sequencing (ExSEQ), Co-detection by Indexing (CODEX) and Multiplexed Ion Beam Imaging (MIBI). To date, we have successfully performed single-cell or single …

How the splicing machinery defines exons or introns as the spliced unit has remained a puzzle for 30 years. Here, we demonstrate that peripheral and central regions of the nucleus harbor genes with two distinct exon-intron GC content architectures that differ in the splicing outcome. Genes with low GC content exons, flanked by long introns with lower GC content, are localized in the periphery, and the exons are defined as the spliced unit. Alternative splicing of these genes results in exon skipping. In contrast, the nuclear center contains genes with a high GC content in the exons and short flanking introns. Most splicing of these genes occurs via intron definition, and aberrant splicing leads to intron retention. We demonstrate that the nuclear periphery and center generate different environments for the regulation of alternative splicing and that two sets of splicing factors form discrete regulatory subnetworks for the two …

Single molecule Förster resonance energy transfer (smFRET) is a unique biophysical approach for studying conformational dynamics in biomacromolecules. Photon-by-photon hidden Markov modeling (H2MM) is an analysis tool that can quantify FRET dynamics of single biomolecules, even if they occur on the sub-millisecond timescale. However, dye photophysical transitions intertwined with FRET dynamics may cause artifacts. Here, we introduce multi-parameter H2MM (mpH2MM), which assists in identifying FRET dynamics based on simultaneous observation of multiple experimentally-derived parameters. We show the importance of using mpH2MM to decouple FRET dynamics caused by conformational changes from photophysical transitions in confocal-based smFRET measurements of a DNA hairpin, the maltose binding protein, MalE, and the type-III secretion system effector, YopO, from Yersinia species …

Professor Shimon Vega (1943–2021) of the Weizmann Institute of Science passed away on the 16 th of November. Shimon Vega established theoretical frameworks to develop and explain solid-state nuclear magnetic resonance (NMR) and dynamic nuclear polarization (DNP) techniques and methodologies. His departure left a profound mark on his many students, postdocs, and colleagues. Shortly after his passing, we all assembled spontaneously for an international online meeting to share our reflections and memories of our experiences in Shimon’s lab and how they affected us deeply during that period of time and throughout our scientific careers. These thoughts and feelings were put here into writing.

We compare ergodic properties of the kinetic energy for three stochastic models of subrecoil-laser-cooled gases. One model is based on a heterogeneous random walk (HRW), another is an HRW with long-range jumps (the exponential model), and the other is a mean-field-like approximation of the exponential model (the deterministic model). All the models show an accumulation of the momentum at zero in the long-time limit, and a formal steady state cannot be normalized, i.e., there exists an infinite invariant density. We obtain the exact form of the infinite invariant density and the scaling function for the exponential and deterministic models and devise a useful approximation for the momentum distribution in the HRW model. While the models are kinetically non-identical, it is natural to wonder whether their ergodic properties share common traits, given that they are all described by an infinite invariant density. We show that the answer to this question depends on the type of observable under study. If the observable is integrable, the ergodic properties such as the statistical behavior of the time averages are universal as they are described by the Darling-Kac theorem. In contrast, for non-integrable observables, the models in general exhibit non-identical statistical laws. This implies that focusing on non-integrable observables, we discover non-universal features of the cooling process, that hopefully can lead to a better understanding of the particular model most suitable for a statistical description of the process. This result is expected to hold true for many other systems, beyond laser cooling.

A conventional optical cavity supports modes which are confined because they are unable to leak out of the cavity. Bound state in continuum (BIC) cavities are an unconventional alternative, where light can leak out, but is confined by multimodal destructive interference. BICs are a general wave phenomenon, of particular interest to optics, but BICs and multimodal interference have never been demonstrated at the nanoscale. Here, we demonstrate the first nanophotonic cavities based on BIC-like multimodal interference. This novel confinement mechanism for deep sub-wavelength light shows orders of magnitude improvement in several confinement metrics. Specifically, we obtain cavity volumes below 100x100x3nm^ 3 with quality factors about 100, with extreme cases having 23x23x3nm^ 3 volumes or quality factors above 400. Key to our approach, is the use of pristine crystalline hyperbolic dispersion media …

We present an experimental study of local magnetic imaging in order to visualize the current flow in superconducting networks. We track the evolution of the spatial distribution of the current flow as the network is driven from fully superconducting to fully normal phases. Our results highlight the factors that contribute to the disordered flow in superconducting networks during their collapse, and demonstrate that the current is never uniformly distributed in the network. These results can assist the design and development of circuits based on superconductors and Josephson junctions.

Geometric phase is a key player in many areas of quantum science and technology. In this review article, several foundational aspects of quantum geometric phases and their relations to classical geometric phases are outlined. How the Aharonov–Bohm and Sagnac effects fit into this context is then discussed. Moreover, a concise overview of technological applications of the latter, with special emphasis on gravitational sensing, like in gyroscopes and gravitational wave detectors is presented.

Distinguishing between d and l enantiomers is of important scientific interest, especially for the pharmaceutical industry. Enantiomeric differentiation in the solid form is repeatedly presented as a challenge in the research community. Raman spectroscopy is a nondestructive tool, widely used for the characterization of different materials by probing their vibrational modes. The low-frequency region of the Raman spectrum reveals lattice-level interactions and global fluctuations in the molecule. Lower frequencies correspond to vibrations arising from weaker bonds and long-range interactions and hence are very susceptible to polarization changes. This work presents low-frequency Raman (LFR) spectroscopy as a facile technique to identify enantiomers. The optical setup of conventional Raman spectroscopy is engineered such that the excitation and collection geometries use an asymmetrical focal cone. In addition, a …