BINA

Biosensors are analytical devices with a wide range of uses in various fields such as food, military, environmental monitoring, and clinical diagnostics. Similarly, polymers and their composites have sparked a lot of interest in biosensing because of their properties, including compatibility with biological molecules, efficient electron transfer during biochemical reactions, bioreagent loading, and biomolecule immobilization. Different nanoparticles such as carbon nanotubes, graphenes, gold nanoparticles, etc., have been efficiently integrated into the polymer matrix to improve performance features such as rapid response, high selectivity, improved sensitivity, long-term stability, and lower detection limit. Polymers in combination with nanomaterials provide a three-dimensional matrix that preserves biomolecule activity and provides an excellent platform for immobilization due to their good durability, porosity, selectivity …

The short time (large energy) behavior of the Sachdev-Ye-Kitaev model (SYK) is one of the main reasons for the growing interest garnered by this model. True chaotic behavior sets in at the Thouless time, which can be extracted from the energy spectrum. In order to do so, it is necessary to unfold the spectrum, ie, to filter out global tendencies. Using a simple ensemble average for unfolding results in a parametically low estimation of the Thouless energy. By examining the behavior of the spectrum as the distribution of the matrix elements is changed into a log-normal distribution, it is shown that the sample-to-sample level spacing variance determines this estimation of the Thouless energy. Using the singular value decomposition method, which filters out these global sample-to-sample fluctuations, the Thouless energy becomes parametrically much larger, essentially of the order of the band width. It is shown that the …

Integration of information over the central nervous system is an important neural process that affects our ability to perceive and react to the environment. The visual system is required to continuously integrate information arriving from two different sources (the eyes) to create a coherent percept with high spatiotemporal precision. Although this neural integration of information is assumed to be critical for visual performance, it can be impaired under some pathological or developmental conditions. Here we took advantage of a unique developmental condition, amblyopia (“lazy eye”), which is characterized by an impaired temporal synchronization between the two eyes, to meticulously study the effect of synchronization on the integration of binocular visual information. We measured the eyes’ asynchrony and compensated for it (with millisecond temporal resolution) by providing time-shifted stimuli to the eyes. We found …

Physical interpretations of the time-symmetric formulation of quantum mechanics, due to Aharonov, Bergmann, and Lebowitz are discussed in terms of weak values. The most direct, yet somewhat naive, interpretation uses the time-symmetric formulation to assign eigenvalues to unmeasured observables of a system, which results in logical paradoxes, and no clear physical picture. A top-down ontological model is introduced that treats the weak values of observables as physically real during the time between pre- and post-selection (PPS), which avoids these paradoxes. The generally delocalized rank-1 projectors of a quantum system describe its fundamental ontological elements, and the highest-rank projectors corresponding to individual localized objects describe an emergent particle model, with unusual particles whose masses and energies may be negative or imaginary. This retrocausal top-down model leads to an intuitive particle-based ontological picture, wherein weak measurements directly probe the properties of these exotic particles, which exist whether or not they are actually measured

At both conceptual and applied levels, quantum physics provides new opportunities as well as fundamental limitations. We hypothetically ask whether quantum games inspired by population dynamics can benefit from unique features of quantum mechanics such as entanglement and nonlocality. For doing so, we extend quantum game theory and demonstrate that in certain models inspired by ecological systems where several predators feed on the same prey, the strength of quantum entanglement between the various species has a profound effect on the asymptotic behavior of the system. For example, if there are sufficiently many predator species who are all equally correlated with their prey, they are all driven to extinction. Our results are derived in two ways: by analyzing the asymptotic dynamics of the system, and also by modeling the system as a quantum correlation network. The latter approach enables us to apply various tools from classical network theory in the above quantum scenarios. Several generalizations and applications are discussed.

Biosensors are analytical devices with a wide range of uses in various fields such as food, military, environmental monitoring, and clinical diagnostics. Similarly, polymers and their composites have sparked a lot of interest in biosensing because of their properties, including compatibility with biological molecules, efficient electron transfer during biochemical reactions, bioreagent loading, and biomolecule immobilization. Different nanoparticles such as carbon nanotubes, graphenes, gold nanoparticles, etc., have been efficiently integrated into the polymer matrix to improve performance features such as rapid response, high selectivity, improved sensitivity, long-term stability, and lower detection limit. Polymers in combination with nanomaterials provide a three-dimensional matrix that preserves biomolecule activity and provides an excellent platform for immobilization due to their good durability, porosity, selectivity …

The electrocatalytic CO2 reduction in aqueous solution mainly involves bond cleavage and formation between C, H and O, and it is highly desirable to expand the bond formation reaction of C with other atoms to obtain novel and valuable chemicals. The electrochemical synthesis of N-containing organic chemicals in electrocatalytic CO2 reduction via introducing N sources is an effective strategy to expand the product scope, since chemicals containing C–N bonds (e.g. amides and amines) are important reactants/products for medicine, agriculture and industry. This article focuses on the research progress of C–N coupling from CO2 and inorganic nitrogenous species in aqueous solution. Firstly, the reaction pathways related to the reaction intermediates for urea, formamide, acetamide, methylamine and ethylamine are highlighted. Then, the electrocatalytic performance of different catalysts for these several N …

A distinguishing feature of ultracold collisions of bosonic lithium atoms is the presence of two near-degenerate two-body continua. The influence of such a near-degeneracy on the few-body physics in the vicinity of a narrow Feshbach resonance is investigated within the framework of a minimal model with two atomic continua and one closed molecular channel. The model allows analysis of the spin composition of loosely bound dimers and trimers. In the two-body sector the well-established coupled-channels calculations phenomenology of lithium is qualitatively reproduced, and its particularities are emphasized and clarified. In the three-body sector we find that the Efimov trimer energy levels follow a different functional form as compared to a single continuum scenario while the thresholds remain untouched. This three-channel model with two atomic continua complements our earlier developed three-channel model with two molecular channels [Y. Yudkin and L. Khaykovich, Phys. Rev. A 103, 063303 (2021)] and suggests that the experimentally observed exotic behavior of the first excited Efimov energy level [Y. Yudkin, R. Elbaz and L. Khaykovich, arXiv:2004.02723] is most probably caused by the short-range details of the interaction potential.

Metal transcription factors regulate metal concentrations in eukaryotic and prokaryotic cells. Copper is a metal ion that is being tightly regulated, owing to its dual nature. Whereas copper is an essential nutrient for bacteria, it is also toxic at high concentrations. CopY is a metal-sensitive transcription factor belonging to the copper-responsive repressor family found in Gram-positive bacteria. CopY represses transcription in the presence of Zn(II) ions and initiates transcription in the presence of Cu(I) ions. The complete crystal structure of CopY has not been reported yet, therefore most of the structural information on this protein is based on its similarity to the well-studied MecI protein. In this study, electron paramagnetic resonance (EPR) spectroscopy was used to characterize structural and local dynamical changes in Streptococcus pneumoniae CopY as a function of Zn(II), Cu(I), and DNA binding. We detected different …

Fermi liquids respond differently to perturbations depending on whether their frequency is larger (collisionless regime) or smaller (hydrodynamic regime) than the inter-particle collision rate. This results in a different phase velocity between the collisionless zero sound and hydrodynamic first sound. We performed terahertz photocurrent nanoscopy measurements on graphene devices, with a metallic gate in close proximity to the sample, to probe the dispersion of propagating acoustic plasmons, the counterpart of sound modes in electronic Fermi liquids. We report the observation of a change in the plasmon phase velocity when the excitation frequency approaches the electron-electron collision rate. This first observation of the first sound mode in an electronic Fermi liquid is of fundamental interest and can enable novel terahertz emitter and detection implementations.

Copper chalcogenides are materials characterized by intrinsic doping properties, allowing them to display high carrier concentrations due to their defect‐heavy structures, independent of the preparation method. Such high doping enables these materials to display plasmonic resonances, tunable by varying their stoichiometry. Here, plasmonic dynamics is studied in drop‐cast Cu9S5 (digenite) nanocrystals (NCs) film using ultrafast pump–probe spectroscopy. The NCs are synthesized by thermal annealing of copper foil using chemical vapor deposition (CVD), followed by sonication and drop‐casting of the isolated few‐layered flakes on different substrates. The samples display a broad localized surface plasmon resonance (LSPR) in the near‐infrared (NIR), peaking at 2100 nm. The free carrier response is further confirmed by fitting the linear absorption with a Drude–Lorentz effective medium approximation model …

Under ultrasonication, cuprous oxide (Cu2O) microparticles (<5 µm) were fragmented into nanoparticles (NPs, ranging from 10 to 30 nm in diameter), and interacted strongly with alkali lignin (Mw = 10 kDa) to form a nanocomposite. The ultrasonic wave generates strong binding interaction between lignin and Cu2O. The L-Cu nanocomposite exhibited synergistic effects with enhanced antibiofilm activities against E. coli, multidrug-resistant (MDR) E. coli, S. aureus (SA), methicillin-resistant SA, and P. aeruginosa (PA). The lignin-Cu2O (L-Cu) nanocomposite also imparted notable eradication of such bacterial biofilms. Experimental evidence unraveled the destruction of bacterial cell walls by L-Cu, which interacted strongly with the bacterial membrane. After exposure to L-Cu, the bacterial cells lost the integrated structural morphology. The estimated MIC for biofilm inhibition for the five tested pathogens was 1 mg …

This review describes the use of Electron Paramagnetic Resonance (EPR) to measure residue specific dynamics in proteins with a specific focus on Cu(II)‐based spin labels. First, we outline approaches used to measure protein motion by nitroxide‐based spin labels. Here, we describe conceptual details and outline challenges that limit the use of nitroxide spin labels to solvent‐exposed α‐helical sites. The bulk of this review showcases the use of newly developed Cu(II)‐based protein labels. In this approach, the strategic mutation of native residues on a protein to generate two neighboring Histidine residues (i.e., the dHis motif) is exploited to enable a rigid site‐selective binding of a Cu(II) complex. The chelation of the Cu(II) complex to dHis directly anchors the Cu(II) spin label to the protein backbone. The improvement in rigidity expands both the spin‐labeling toolkit as well as the resolution of many EPR …

Single-molecule FRET (smFRET) has become an established tool to study biomolecular structure and dynamics in vitro and in live cells. We performed a worldwide blind study involving 19 labs to assess the uncertainty of FRET experiments for proteins with respect to the measured FRET efficiency histograms, determination of distances, and the detection and quantification of structural dynamics. Using two protein systems that undergo distinct conformational changes, we obtained an uncertainty of the FRET efficiency of less than 0.06, corresponding to an interdye distance precision of less than 0.2 nm and accuracy of less than 0.5 nm. We further discuss the limits for detecting distance fluctuations with sensitivity down to less than 10% of the Foerster distance and provide guidelines on how to detect potential dye perturbations. The ability of smFRET experiments to simultaneously measure distances and avoid averaging of conformational dynamics slower than the fluorescence lifetime is unique for dynamic structural biology.

A hydrothermal method was conducted to synthesize Ni(1−α)Co(α)MoO4 (α = 0, 0.1, 0.3, and 0.5 M) nanorods, which were proven as excellent electrode materials in a hybrid supercapacitor. Their electrochemical properties were also dependent on the Ni/Co ratio as demonstrated by different electrochemical techniques. Ni0.5Co0.5MoO4 (α = 0.5 M) offered specific capacity (Qg) = 354 Cg–1@1 Ag–1, a remarkable specific capacity with a notable retention capacity of 92% after 8000 repeated cycles at 10 Ag–1. Ni0.5Co0.5MoO4 with a high surface area outperformed the mono-metallic (NiMoO4) and bimetallic (Ni0.9Co0.1MoO4 and Ni0.7Co0.3MoO4) nanostructures. The hybrid supercapacitor (Ni0.5Co0.5MoO4//activated carbon) delivered a maximum Qcell of 53 Cg–1 at 1 Ag–1 with an energy density of 16.2 Wh kg–1 and power density of 725 W kg–1.

A major challenge in radiation oncology is predicting and optimizing a clinical response on a personalized manner. Recently, nanotechnology-based cancer treatments are being combined with photodynamic therapy (PDT) and photothermal therapy (PTT). Machine learning predictive models can be used to optimize the clinical setup configuration, such as: laser radiation intensity, treatment duration, and nanoparticles features. In this work we demonstrate a methodology to find the optimized treatment parameters for PDT and PTT by collecting data of in vitro cytotoxicity assay of PDT/PTT-induced cell death using a single nanocomplex. We examine three machine learning prediction models of regression, interpolation, and low degree analytical function to predict the laser radiation intensity and duration that maximize the treatment efficiency. To examine these prediction models accuracy, we built a dedicated dataset for PDT, PTT, and a combined treatment that is based on cell death measurements after light radiation treatment, divided to training and test sets. The preliminary results show that all models offer sufficient performance with death rate error of 0.09, 0.15, and 0.12 for the regression, interpolation, and analytical function fitting. Nevertheless, the analytical function due to its simple form has a clinical application advantage that can be used for further sensitivity analysis of the treatment parameters on the performance. In all, the results of this work form a baseline for a future machine learning base personal prediction model in combined nanotechnology-based phototherapy cancer treatment.

Hierarchical organic structures have gained vast attention in the past decade owing to their great potential in chemical and medical applications in industries such as the food and pharmaceutical industries. In this paper, the crystallization of L-glu hierarchical spheres using inorganic ions, namely calcium, barium and strontium cations, is described. The anti-solvent precipitation method is used for the spherical crystallization. The L-glu microspheres are characterized using various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photo-electron microscopy (XPS) and polarized microscopy (POM). It is shown that without additives, L-glu crystallizes as flower-like structures, very different from the hierarchical spheres crystallized with the charged additives. Based on our results, we suggest a mechanism for the hierarchical sphere formation based on the crystallization and self-assembly of L-glu in emulsion droplets using charged additives.

Sonochemistry in now well recognized as a technique for the fabrication of nanomaterials. This is reflected in the many review articles on sonochemistry and nanoparticles that have been published over the last few years. It is so happened that Suslick, one of the forefathers of this field, has lately written a very comprehensive review on this topic (Bang, 2010). In his review, Suslick has summarized the work published on sonochemistry and nanomaterials until 2010. The current review will try to scan the work done in this area until the end of 2012. The current review will concentrate first on explaining why nano? Namely, when, why, and what kind of nanomaterials are produced upon the collapse of the acoustic bubble?

Background & AimsHepatocellular carcinoma (HCC) is a model of a diverse spectrum of cancers because it is induced by well-known etiologies, mainly hepatitis C virus (HCV) and hepatitis B virus. Here, we aimed to identify HCV-specific mutational signatures and explored the link between the HCV-related regional variation in mutations rates and HCV-induced alterations in genome-wide chromatin organization.MethodsTo identify an HCV-specific mutational signature in HCC, we performed high-resolution targeted sequencing to detect passenger mutations on 64 HCC samples from 3 etiology groups: hepatitis B virus, HCV, or other. To explore the link between the genomic signature and genome-wide chromatin organization we performed chromatin immunoprecipitation sequencing for the transcriptionally permissive H3K4Me3, H3K9Ac, and suppressive H3K9Me3 modifications after HCV infection.Results …

Superhydrophobic surface preparation is developed by inspiration from nature. As it is a natural fact that lotus leaves are water repellant, thus researchers tried their best to develop superhydrophobic coatings by using several materials. The materials are categorized by inorganic, organic, and their synergistic hybrids. Polymeric coatings are more usable by scientists because of its tunable chemical features and their internal morphologies. This chapter will discuss in brief the coating materials and how polymer systems influenced the superhydrophobicity.

We demonstrate an improved YBa 2 Cu 3 O 7-δ-based microwave kinetic inductance detector with a quality factor and noise equivalent power, $\sim {10^{-12}}{\mkern 1mu}{\text {W}}{\mkern 1mu}{\sqrt {{\text {Hz}}}^{-1}} $ at 10 K. Zero field cooled (ZFC) and field cooled (FC) measurements of the magnetic field dependence of the resonance characteristics, show substantially different behavior, indicating that both the screening currents and vortices play a role. The ZFC measurements exhibit a sharp decrease of the resonance frequency, , and at low fields, up to the full penetration field, revealing the dominant role of the screening currents. In contrast, the FC measurements exhibit a moderate decrease of and with field, revealing the role of vortices and reflecting the field dependence of the penetration depth in a d-wave superconductor.