BINA

X-ray imaging is a prevalent technique for non-invasively visualizing the interior of the human body and opaque instruments. In most commercial x-ray modalities, an image is formed by measuring the x-rays that pass through the object of interest. However, despite the potential of scattered radiation to provide additional information about the object, it is often disregarded due to its inherent tendency to cause blurring. Consequently, conventional imaging modalities do not measure or utilize these valuable data. In contrast, we propose and experimentally demonstrate a high-resolution technique for x-ray computed tomography (CT) that measures scattered radiation by exploiting computational ghost imaging (CGI). We show that our method can provide sub-200 {\mu}m resolution, exceeding the capabilities of most existing x-ray imaging modalities. Our research reveals a promising technique for incorporating scattered radiation data in CT scans to improve image resolution and minimize radiation exposure for patients. The findings of our study suggest that our technique could represent a significant advancement in the fields of medical and industrial imaging, with the potential to enhance the accuracy and safety of diagnostic imaging procedures.

The Kirkwood-Dirac quasiprobability distribution emerges from the quantum correlation function of two observables measured at distinct times and is therefore relevant for fundamental physics and quantum technologies. These quasiprobabilities follow all but one of Kolmogorov axioms for joint probability distributions: they can take non-positive values. Their experimental reconstruction becomes challenging when expectation values of incompatible observables are involved. Previous strategies aimed to reconstruct them using weak measurements or combining strong measurements. Here, we use a more direct approach, an interferometric scheme aided by an auxiliary system, to reconstruct the Kirkwood-Dirac quasiprobability distribution. We experimentally demonstrate the interferometric scheme in an electron-nuclear spin system associated with a nitrogen-vacancy center in diamond. By measuring the characteristic function, we reconstruct the quasiprobability distribution of the work and analyze the behavior of the first and second moments of work. Our results clarify the physical meaning of the work quasiprobability distribution in the context of quantum thermodynamics. Finally, having measured the real and imaginary parts of the Kirkwood-Dirac quasiprobability of work, we are also able to study the uncertainty of measuring the Hamiltonian of the system at two times, via the Robertson-Schr{\"o}dinger uncertainty relation, for different initial states.

The term defect tolerance (DT) is used often to rationalize the exceptional optoelectronic properties of Halide Perovskites, HaPs, and their devices. Even though DT lacked direct experimental evidence, it became fact in the field. DT in semiconductors implies tolerance to structural defects without the electrical and optical effects (e.g., traps), associated with such defects. We present first direct experimental evidence for DT in Pb HaPs by comparing the structural quality of 2D, 2D_3D, and 3D Pb HaP crystals with their optoelectronic characteristics using high sensitivity methods. Importantly, we get information from the material bulk, because we sample at least a few 100 nm, up to several micrometer, from the sample surface, which allows assessing intrinsic bulk (and not only surface) properties of HaPs. The results point to DT in 3D, to a lesser extent in 2D_3D, but not in 2D Pb HaPs. We ascribe such dimension dependent DT to the higher number of (near)neighboring species, available to compensate for structural defect effects in the 3D than in the 2D HaP crystals. Overall, our data provide an experimental basis to rationalize DT in Pb HaPs. These experiments and findings can guide the search for, and design of other materials with DT.

Electrocatalysts play a critical role in energy technologies, but the development of active, efficient, and durable catalysts is impeded by the lack of methodologies to deconvolute the complex interplay between various aspects influencing the activity of the catalysts, e.g., the number of active sites, turnover frequency, and the reaction pathways. Fourier-transformed alternating current voltammetry (FTacV) is an emerging tool for the analysis of electroactive species and has been successfully applied to a variety of reactions such as the oxygen reduction reaction, oxygen evolution reaction, carbon dioxide reduction reaction, hydrogen evolution reaction, and hydrogen oxidation reaction. The harmonics generated from FTacV measurements neatly detect underlaying processes not visible by other, more commonly employed techniques for analysis of electrocatalysts, such as the rotating disc electrode and dc voltammetry …

Super-enhancers are unique gene expression regulators widely involved in cancer development. Spread over large DNA segments, they tend to be found next to oncogenes. The super-enhancer c-MYC locus forms long-range chromatin looping with nearby genes, which brings the enhancer and the genes into proximity, to promote gene activation. The colon cancer-associated transcript 1 (CCAT1) gene, which is part of the MYC locus, transcribes a lncRNA that is overexpressed in colon cancer cells through activation by MYC. Comparing different types of cancer cell lines using RNA fluorescence in situ hybridization (RNA FISH), we detected very prominent CCAT1 expression in HeLa cells, observed as several large CCAT1 nuclear foci. We found that dozens of CCAT1 transcripts accumulate on the gene locus, in addition to active transcription occurring from the gene. The accumulating transcripts are released …

Enhancing the reproducibility and comprehension of adaptive immune receptor repertoire sequencing (AIRR-seq) data analysis is critical for scientific progress. This study presents guidelines for reproducible AIRR-seq data analysis, and a collection of ready-to-use pipelines with comprehensive documentation. To this end, ten common pipelines were implemented using ViaFoundry, a user-friendly interface for pipeline management and automation. This is accompanied by versioned containers, documentation and archiving capabilities. The automation of pre-processing analysis steps and the ability to modify pipeline parameters according to specific research needs are emphasized. AIRR-seq data analysis is highly sensitive to varying parameters and setups; using the guidelines presented here, the ability to reproduce previously published results is demonstrated. This work promotes transparency …

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 …

Self‐assembly of biological elements into biomimetic cargo carriers for targeting and delivery is a promising approach. However, it still holds practical challenges. We developed a functionalization approach of DNA origami (DO) nanostructures with neuronal growth factor (NGF) for manipulating neuronal systems. NGF bioactivity and its interactions with the neuronal system were demonstrated in vitro and in vivo models. The DO elements fabricated by molecular self‐assembly have manipulated the surrounding environment through static spatially and temporally controlled presentation of ligands to the cell surface receptors. Our data showed effective bioactivity in differentiating PC12 cells in vitro. Furthermore, the DNA origami NGF (DON) affected the growth directionality and spatial capabilities of dorsal root ganglion neurons in culture by introducing a chemotaxis effect along a gradient of functionalized DO …

Terpene synthases (TPSs) catalyze the first step in the formation of terpenoids, which comprise the largest class of natural products in nature. TPSs employ a family of universal natural substrates, composed of isoprenoid units bound to a diphosphate moiety. The intricate structures generated by TPSs are the result of substrate binding and folding in the active site, enzyme‐controlled carbocation reaction cascades, and final reaction quenching. A key unaddressed question in class I TPSs is the asymmetric nature of the diphosphate‐(Mg2+)3 cluster, which forms a critical part of the active site. In this asymmetric ion cluster, two diphosphate oxygen atoms protrude into the active site pocket. The substrate hydrocarbon tail, which is eventually molded into terpenes, can bind to either of these oxygen atoms, yet to which is unknown. Herein, we employ structural, bioinformatics, and EnzyDock docking tools to address this …

Insertion of hydrophobic nanoparticles into phospholipid bilayers is limited to small particles that can incorporate into a hydrophobic membrane core between two lipid leaflets. Incorporation of nanoparticles above this size limit requires the development of challenging surface engineering methodologies. In principle, increasing the long-chain lipid component in the lipid mixture should facilitate incorporation of larger nanoparticles. Here, we explore the effect of incorporating very long phospholipids (C24:1) into small unilamellar vesicles on the membrane insertion efficiency of hydrophobic nanoparticles that are 5–11 nm in diameter. To this end, we improve an existing vesicle preparation protocol and utilized cryogenic electron microscopy imaging to examine the mode of interaction and evaluate the insertion efficiency of membrane-inserted nanoparticles. We also perform classical coarse-grained molecular …

Layered transition metal dichalcogenides (TMDCs) are considered among the next-generation materials for gas sensing. Here, we report exfoliated 2 H-WS 2 nanosheets for the fabrication of highly performing NO 2 sensors. Thermal annealing at several temperatures was performed to investigate the oxidation of WS 2. The long-term stability of 2 H-WS 2 bulk was verified. Using droplet variation method, three batches of conductometric sensors from 2 H-WS 2 dispersions were fabricated on electrical transducers, namely two layers (2 L), five layers (5 L) and ten layers (10 L) WS 2 nanosheets. These sensors were tested towards low NO 2 concentrations at different temperatures (Room Temperature (20℃), 50℃ and 100℃) and relative humidity (RH) levels (20%, 40%, 60%, 80% and 90% RH). 2 L-WS 2 based sensor showed the highest response at room temperature (RT). Excellent repeatability (4 cycles) towards 1 …

Materials that transition between metal and insulator, the two opposing states that distinguish all solids, are fascinating because they underlie many mysteries in the physics of the solid state. In 1T-TaS, the metal-insulator transition is linked to a series of metastable states of a chiral charge density wave whose basic nature is still an open question. In this work, we show that pulses of current through these materials create current-carrying boundary channels that distinguish the metallic and insulating states. We demonstrate electrical control of these channels' properties, suggesting their formation could be due to the complex interplay of the formation of domain walls and the viscous flow of electrons. Our findings show that physical boundaries play a key role in the properties of the metastable states of the metal-insulator transition, highlighting new possibilities for in-situ electrical design and active manipulation of electrical components.

Magnetic field-induced changes in the electrical resistance of materials reveal insights into the fundamental properties governing their electronic and magnetic behavior. Various classes of magnetoresistance have been realized, including giant, colossal, and extraordinary magnetoresistance, each with distinct physical origins. In recent years, extreme magnetoresistance (XMR) has been observed in topological and non-topological materials displaying a non-saturating magnetoresistance reaching 103−108% in magnetic fields up to 60 T. XMR is often intimately linked to a gapless band structure with steep bands and charge compensation. Here, we show that a linear XMR of 80,000% at 15 T and 2 K emerges at the high-mobility interface between the large band-gap oxides γ-Al2O3 and SrTiO3. Despite the chemically and electronically very dissimilar environment, the temperature/field phase diagrams of γ-Al2O …

The Kirkwood-Dirac quasiprobability distribution emerges from the quantum correlation function of two observables measured at distinct times and is therefore relevant for fundamental physics and quantum technologies. These quasiprobabilities follow all but one of Kolmogorov axioms for joint probability distributions: they can take non-positive values. Their experimental reconstruction becomes challenging when expectation values of incompatible observables are involved. Previous strategies aimed to reconstruct them using weak measurements or combining strong measurements. Here, we use a more direct approach, an interferometric scheme aided by an auxiliary system, to reconstruct the Kirkwood-Dirac quasiprobability distribution. We experimentally demonstrate the interferometric scheme in an electron-nuclear spin system associated with a nitrogen-vacancy center in diamond. By measuring the characteristic function, we reconstruct the quasiprobability distribution of the work and analyze the behavior of the first and second moments of work. Our results clarify the physical meaning of the work quasiprobability distribution in the context of quantum thermodynamics. Finally, having measured the real and imaginary parts of the Kirkwood-Dirac quasiprobability of work, we are also able to study the uncertainty of measuring the Hamiltonian of the system at two times, via the Robertson-Schr{\"o}dinger uncertainty relation, for different initial states.

Nanoparticles are widely used in construction. Here, nano-SiO2 is employed, in a way that prevents agglomeration of the nanoparticles, as pozzolanic material to improve Portland cement hydration and to improve the properties of the concrete. To explore the effect of nano-SiO2 and core-shell PS@SiO2 on cement properties, spherical polystyrene particles were prepared by dispersion polymerization of styrene in polar solvents and characterized by FTIR and E-SEM. The core shells PS@SiO2 were synthesized by Stöber method. The results showed an amorphous nano-SiO2 layer can be deposited uniformly on polystyrene particles. This core/shell structure was reducing the aggregation of nano-SiO2 effectively. It was shown that PS@SiO2 particles improved the concrete performances compared to blended cement with nano-SiO2 due to the agglomeration affect. Highlights •Core/shell PS@SiO2 nanoparticles …

In recent years, steady progress has been made in synthesizing and characterizing engineered nanoparticles, resulting in several approved drugs and multiple promising candidates in clinical trials. Regulatory agencies such as the Food and Drug Administration and the European Medicines Agency released important guidance documents facilitating nanoparticle-based drug product development, particularly in the context of liposomes and lipid-based carriers. Even with the progress achieved, it is clear that many barriers must still be overcome to accelerate translation into the clinic. At the recent conference workshop “Mechanisms and Barriers in Nanomedicine” in May 2023 in Colorado, U.S.A., leading experts discussed the formulation, physiological, immunological, regulatory, clinical, and educational barriers. This position paper invites open, unrestricted, nonproprietary discussion among senior faculty, young …

X-ray imaging is a prevalent technique for non-invasively visualizing the interior of the human body and opaque instruments. In most commercial x-ray modalities, an image is formed by measuring the x-rays that pass through the object of interest. However, despite the potential of scattered radiation to provide additional information about the object, it is often disregarded due to its inherent tendency to cause blurring. Consequently, conventional imaging modalities do not measure or utilize these valuable data. In contrast, we propose and experimentally demonstrate a high-resolution technique for x-ray computed tomography (CT) that measures scattered radiation by exploiting computational ghost imaging (CGI). We show that our method can provide sub-200 {\mu}m resolution, exceeding the capabilities of most existing x-ray imaging modalities. Our research reveals a promising technique for incorporating scattered radiation data in CT scans to improve image resolution and minimize radiation exposure for patients. The findings of our study suggest that our technique could represent a significant advancement in the fields of medical and industrial imaging, with the potential to enhance the accuracy and safety of diagnostic imaging procedures.

Carbonaceous materials are the most common catalyst supports in proton exchange membrane fuel cell (PEMFCs), yet their corrosion is one of the limiting factors in achieving high durability. Herein, we doped carbon supports with boron (B) to increase the corrosion-resistance of the support. Two types of B-doped carbons were synthesized and studied as platinum support materials. They varied in their morphologies, surface areas, and the types of boron species. The durability of Pt/B-doped carbon catalysts was investigated using the US-DOE catalysts’ supports accelerated stress test (AST) and a mass-spectrometer connected to the fuel cell effluent stream to quantify the mass of corroded carbon support in operando. The addition of boron to the carbon increased the stability of Pt catalysts in long-term usage of PEMFC. After 4,000 AST cycles, more than 50% of initial current density was preserved for the boron …

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).

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 …