BINA

Interaction-free measurement (IFM) is a promising technique for low-dose detection and imaging, offering the unique advantage of probing an object without absorption of the interrogating photons. We propose an experiment to demonstrate IFM in the single x-ray photon regime. The proposed scheme relies on the triple-Laue (LLL) symmetric x-ray interferometer, where each Laue diffraction acts as a lossy beamsplitter. In contrast to many quantum effects which are highly vulnerable to loss, we show that an experimental demonstration of this effect in the x-ray regime is feasible and can achieve high IFM efficiency even in the presence of substantial loss in the system. The latter aspect is claimed to be a general property of IFM based on our theoretical analysis. We scrutinize two suitable detection schemes that offer efficiencies of up to . The successful demonstration of IFM with x-rays promises intriguing possibilities for measurements with reduced dose, mainly advantageous for biological samples, where radiation damage is a significant limitation.

We report continuous wave laser-assisted evaporation (CLE), a thin film deposition technique that yields phase-pure and stoichiometric thin films of halide perovskites (HaPs) from stoichiometric HaP targets. We use methylammonium lead bromide (MAPbBr 3) to demonstrate the ability to grow with CLE well-oriented and smooth thin films on various substrates. Further, we show the broader applicability of CLE by preparing films of several other 3D HaP compounds, viz., methylammonium lead iodide, formamidinium lead bromide, and a 2D one, butylammonium lead iodide. CLE is a single-source, solvent-free, room-temperature process that needs only roughing pump vacuum; it allows the deposition of hybrid organic-inorganic compound films without needing post-thermal treatment or an additional organic precursor source to yield the intended product. The resulting films are polycrystalline and highly oriented. All …

Visible light-active photoelectrode materials that can exhibit simultaneous photo- and electroactivity are essential for photoelectrosynthesis. Herein, we report a coordination metallo-organic system based on bismuth with 2,5-dimercapto-1,3,4-thiadiazole (DMcT) as a linker ligand, which displays a p-type behavior with stable photoelectroactivity in neutral and protic electrolytes. The UV–visible spectral investigation reveals the systematic bathochromic shift with a gradual increment in the concentration of the Bi3+ ions to DMcT and the bandgap of 1.7 eV. The XPS, Raman, and FT-IR spectral data suggest the presence of a −S–Bi–S– linkage in the c-Bi-DMcT coordination polymeric structures. A photocathode prepared by electrooxidation shows a relatively less bismuth content with a disulfide linkage and lower photoactivity compared with c-Bi-DMcT prepared by chemical synthesis. The observed photocurrent values …

One of the most challenging tasks in analytical chemistry is the determination of the chirality (identi cation of an enantio-meric composition) in solids mainly because of the strict requirements of the pharmaceutical industry for enantiomerically pure drugs. Although there are a few methods available to accomplish enantio-differentiation in solids, for example: X-ray diffraction (XRD), differential scanning calorimetry (DSC), CD spectroscopy, and low-frequency (LF) Raman spectroscopy, this is still very challenging. In this work, we have developed a new method to measure the chirality of crystals, based on electron paramagnetic resonance (EPR) spectroscopy of chiral crystals doped with Cu2+ as the EPR active ion. Here, we demonstrate our approach using a model system of L-and DL-Histidine crystals doped with Cu2+. We show that EPR measurements of the Cu2+-doped Histidine crystals can accurately determine the chirality and enantiomeric composition of the crystals. We present a very preliminary example of this technique, and we hope that in the future it will be possible to re ne and develop this method for many other chiral organic crystal systems.

Optical properties of chalcogenide topological insulators (TIs), namely, Bi2Se3 (BS) and Bi2Te3 (BT) were studied across the NIR to MIR spectral ranges. In this spectral range, the experimentally measured optical constants revealed an extremely high permittivity values amounting to refractive indices as high as n≈11 and n≈6.4, for BT and BS respectively. These ultra-high index values were then utilized for demonstrating ultracompact, deep-subwavelength nanostructures (NSs), with unit cell sizes down to ~λ/10. Finally, using scattering-type Scanning Near-field Optical Microscopy (s-SNOM), local variations in the optical constants of these nanostructured TIs were studied. Nanoscale phase mapping on a BS NS revealed the role of the imaginary component of the refractive index in the observed phase shifts, varying from as low as ~0.37π to a maximum of ~2π radians across a resonance. This work thus highlights …

Optical properties of chalcogenide topological insulators (TIs), namely, Bi2Se3 (BS) and Bi2Te3 (BT) were studied across the NIR to MIR spectral ranges. In this spectral range, the experimentally measured optical constants revealed an extremely high permittivity values amounting to refractive indices as high as n≈11 and n≈6.4, for BT and BS respectively. These ultra-high index values were then utilized for demonstrating ultracompact, deep-subwavelength nanostructures (NSs), with unit cell sizes down to ~λ/10. Finally, using scattering-type Scanning Near-field Optical Microscopy (s-SNOM), local variations in the optical constants of these nanostructured TIs were studied. Nanoscale phase mapping on a BS NS revealed the role of the imaginary component of the refractive index in the observed phase shifts, varying from as low as ~0.37π to a maximum of ~2π radians across a resonance. This work thus highlights …

Several decades after the invention of the flow Zn-Br2 systems, persistent attempts have been made to develop stationary Zn-Br2 batteries. Such development should increase the energy density of the system simultaneously significantly reducing their cost and opening new challenges associated with the cell design and its performance. One of the major concerns is the rapid self-discharge of stationary systems leading to spontaneous charge loss during battery storage time. While self-discharge in flow cells is generally attributed to the chemical oxidation of the Zn anode, we show that the origin of self-discharge in a static configuration is completely different. By systematic investigations of activated carbon with different surface areas under varied charging conditions, mechanistic insights into this phenomenon were provided. Based on this understanding, we proposed herein an effective way to suppress the cathode …

Various biological surfaces are known to be covered by elaborated micro- and nano-structures, serving a number of functions (e.g. anti-reflective, structural coloration, anti-fouling, pro- or anti-adhesive, etc.) and inspiring numerous industrial applications. Recent years have witnessed a remarkable boost in research in this field. To a large extent, this boost owes to the increasing interdisciplinary of approaches being applied to the study of structured biosurfaces. Sciences as different as classical zoology and botany are inseminated with the advances in genetics and molecular biology; biologists collaborate more and more with nanotechnologists, materials scientists and engineers – all these contribute to the widening of the horizons of research on micro- and nano-structured biological surfaces, and to biomimetic and bioengineering applications of these surfaces in industry. We aim at ‘riding the wave’ of these …

Electron Paramagnetic Resonance (EPR) is a powerful tool for elucidating both static and dynamic conformational alterations in macromolecules. However, to effectively utilize EPR for such investigations, the presence of paramagnetic enters, known as spin-labels, is required. The process of spin-labeling, particularly for nucleotides, typically demands intricate organic synthesis techniques. In this study, we introduce a unique addition-elimination reaction method with a simple spin-labeling process, facilitating the monitoring of structural changes within nucleotide sequence. Our investigation focuses on three distinct labeling positions with a DNA sequence, allowing the measurement of distance between two spin-labels. The experimental mean distances obtained agreed with the calculated distances, underscoring the efficacy of this straightforward spin-labelling approach in studying complex biological processes …

Biological structures have evolved to very efficiently generate, transmit, and withstand mechanical forces. These biological examples have inspired mechanical engineers for centuries and led to the development of critical insights and concepts. However, progress in mechanical engineering also raises new questions about biological structures. The past decades have seen the increasing study of failure of engineered structures due to repetitive loading, and its origin in processes such as materials fatigue. Repetitive loading is also experienced by some neurons, for example in the peripheral nervous system. This perspective, after briefly introducing the engineering concept of mechanical fatigue, aims to discuss the potential effects based on our knowledge of cellular responses to mechanical stresses. A particular focus of our discussion are the effects of mechanical stress on axons and their cytoskeletal structures. Furthermore, we highlight the difficulty of imaging these structures and the promise of new microscopy techniques. The identification of repair mechanisms and paradigms underlying long-term stability is an exciting and emerging topic in biology as well as a potential source of inspiration for engineers.

Traditional methods for measuring blood oxygen use multiple wavelengths, which produces an In the biomedical field, the reemitted light intensity measured from the tissue depends on both scattering and absorption. In order to separate these variables, we use a physical phenomenon discovered in our lab, called the iso-path length (IPL) point. The IPL point is a specific angle around a cylindrical media, where the light intensity is not affected by the scattering and can serve for self-calibration. For a practical use of this concept, we designed an optic biosensor for measuring physiological parameters such as heart rate, oxygen saturation and respiratory rate, in both ordinary and extreme conditions in a hypoxic chamber.

Nanomaterials bring to expression unique electronic properties that promote advanced functionality and technologies. Albeit, nanoscale growth presents paramount challenges for synthesis limiting the diversity in structures and compositions. Here, we demonstrate solid-state topotactic exchange that converts Wurtzite InAs nanowires into Zintl phase EuInAs nanowires. In situ evaporation of Eu and As over InAs nanowire cores in molecular beam epitaxy results in mutual exchange of Eu from the shell and In from the core. A continuous EuInAs shell thereby grows that gradually consumes the InAs core and converts it into a single phase EuInAs nanowire. Topotaxy, which facilitates the mutual exchange, is supported by the substructure of the As matrix which is similar across the Wurtzite InAs and Zintl EuInAs. We provide initial evidence of an antiferromagnetic transition at T 6.5 K in the Zintl phase EuInAs nanowires. Ab initio calculation confirms the antiferromagnetic state and classifies EuInAs as a axion insulator hosting both chiral hinge modes and unpinned Dirac surface states. The topotactic mutual-exchange growth of Zintl EuInAs nanowires thus enables the exploration of intricate magneto-topological states of nanomaterials. Moreover, it may open the path for topotactic mutual-exchange synthesis of nanowires made of other exotic compounds.

Quantum correlation functions are a natural way to encode multitime information, as they are ubiquitous in analysis from fluctuation theorems to information scrambling. Correlation functions can be identified with quasiprobabilities associated to quantum processes. In this work we show how these can be measured via error-cancellation techniques, using projective measurements only and no ancillae. The scheme is implemented in a nitrogen-vacancy center in diamond undergoing a unitary quantum work protocol. We reconstruct quantum-mechanical time correlations encoded in the Margenau-Hills quasiprobabilities by observing work extraction peaks five times those of sequential projective energy measurement schemes and in violation of newly derived stochastic bounds. We interpret the phenomenon via anomalous energy exchanges due to the underlying negativity of the quasiprobability distribution.

Background Chronic peripheral inflammation is well-documented for its ability to alter the activation of the central nervous system (CNS) in diseases such as rheumatoid arthritis (RA) [1]. Furthermore, the CNS is able to regulate inflammatory processes in the periphery [2]. However, the environmental factors facilitating CNS-mediated suppression of peripheral inflammation in RA remain less explored. The intestinal microbiota produces immunomodulatory metabolites, including short-chain fatty acids (SCFA) [3], and neuroactive substances like histamine, which exhibit local and systemic effects [4]. While histamine is commonly associated with allergic reactions, it also possesses immunoregulatory function [5].Objectives Our study aimed to elucidate the impact of gut microbiota-derived histamine on peripheral inflammation.Methods Mice with collagen-induced arthritis (CIA) were orally treated with histamine-producing …

Despite their importance, there is an on-going challenge characterizing multipartite quantum correlations. The Svetlichny and Mermin-Klyshko (MK) inequalities present constraints on correlations in multipartite systems, a violation of which allows to classify the correlations by using the non-separability property. In this work we present refined Tsirelson (quantum) bounds on these inequalities, derived from inequalities stemming from a fundamental constraint, tightly akin to quantum uncertainty. Unlike the original, known inequalities, our bounds do not consist of a single constant point but rather depend on correlations in specific subsystems (being local correlations for our bounds on the Svetlichny operators and bipartite correlations for our bounds on the MK operators). We analyze concrete examples in which our bounds are strictly tighter than the known bounds.

Temporal optics revolutionize the field of ultrafast detection with time-lens and time-stretch schemes. We developed a temporal interferometer that enables us to measure ultrafast phase shifts. With this interferometer, we measured phase shifts of correlated beams traveling in different temporal trajectories. This allows us to demonstrate the Aharonov-Bohm effect in the time domain. We developed the theoretical basis of this temporal Aharonov-Bohm effect and showed it in experimental measurements. In the talk, we will explain this effect, describe the experimental setup, and show the results.

Immunoglobulins (IGs), critical components of the human immune system, are composed of heavy and light protein chains encoded at three genomic loci. The IG Kappa (IGK) chain locus consists of two large, inverted segmental duplications. The complexity of the IG loci has hindered use of standard high-throughput methods for characterizing genetic variation within these regions. To overcome these limitations, we use long-read sequencing to create haplotype-resolved IGK assemblies in an ancestrally diverse cohort (n = 36), representing the first comprehensive description of IGK haplotype variation. We identify extensive locus polymorphism, including novel single nucleotide variants (SNVs) and novel structural variants harboring functional IGKV genes. Among 47 functional IGKV genes, we identify 145 alleles, 67 of which were not previously curated. We report inter-population differences in allele frequencies …

Numerous biological surfaces exhibit intricate micro- and nano-structures, which fulfill various functions such as anti-reflective properties, structural coloration, anti-fouling capabilities, and pro- or anti-adhesive characteristics. These features have inspired a plethora of industrial applications. In recent years, there has been a significant surge in research in this domain, largely attributable to the growing interdisciplinary nature of the approaches applied to the investigation of structured biosurfaces. The convergence of classical zoology and botany with advances in genetics and molecular biology is noteworthy, as biologists increasingly collaborate with nanotechnologists, materials scientists, and engineers. This collaborative effort contributes significantly to expanding the horizons of research on micro- and nano-structured biological surfaces, fostering biomimetic and bioengineering applications in various industries …

Bell tests serve as a fundamental tool in both quantum technologies and quantum foundations investigation. The traditional Bell test framework involves the use of projective measurements, which, because of the wavefunction collapse and the Heisenberg uncertainty principle, do not allow for the full estimation of the Bell parameter from each entangled pair. In this work, we propose a novel weak-measurement-based scheme enabling the complete estimation of the entire Bell parameter from each entangled pair. Moreover, this approach prevents the collapse of the quantum state wavefunction, thereby preserving the entanglement within it. Our results, showing a 6 standard deviations violation of the Bell inequality tested, are obtained while leaving the entanglement within the photon pair almost unaltered after the weak measurement scheme (as demonstrated by our quantum tomographic reconstructions), allowing …

Spatial modes in multimode fibers interact with each other through nonlinear processes leading to various spatio-temporal dynamics. Studying the dynamics of such interactions can open a new route for understanding ultrafast modal phenomena. In this research, we measure the temporal and spatial dynamics of ultrafast multimode signals in a high temporal resolution. We study the modal dynamics of each spatial mode inside multimode fibers as a function of time, intensity, and wavelength. We derive the spatial coupling, identify the energy transfer between the modes, and show that it is possible to transfer the energy even when the overlap integral vanishes and the coupling between the modes is zero.

Method: To elucidate the role of ADAR1 in human islets, we first studied ADAR expression and distribution in human pancreas across postnatal developmental timeline (1 day, 4 months, 2, 6, 10, 35 years). Then we transduced human pseudoislets with a shRNA for ADAR and examined their function and gene expression. The transduced pseudoislets were also transplanted into NSG mice. Insulin secretion was measured and grafts were studied.Results: We found that ADAR1 expression at all ages was greater in endocrine cells than acinar cells. Using the shRNA approach, ADAR mRNA levels were reduced by 70%(n= 11 donors). After 7-day culture, expression of dsRNA sensors, IFNB1, IRF7, IRF9, and interferon-stimulated genes was increased while INS and MAFA expression was reduced in ADAR knockdown islets without changes in insulin secretion. However, 3 weeks post transplantation, glucose/arginine …