BINA

The invention of X-ray interferometers has led to advanced phase-sensing devices that are invaluable in various applications. These include the precise measurement of universal constants, e.g. the Avogadro number, of lattice parameters of perfect crystals, and phase-contrast imaging, which resolves details that standard absorption imaging cannot capture. However, the sensitivity and robustness of conventional X-ray interferometers are constrained by factors, such as fabrication precision, beam quality, and, importantly, noise originating from external sources or the sample itself. In this work, we demonstrate a novel X-ray interferometric method of phase measurement with enhanced immunity to various types of noise, by extending, for the first time, the concept of the SU(1,1) interferometer into the X-ray regime. We use a monolithic silicon perfect crystal device with two thin lamellae to generate correlated photon pairs via spontaneous parametric down-conversion (SPDC). Arrival time coincidence and sum-energy filtration allow a high-precision separation of the correlated photon pairs, which carry the phase information from orders-of-magnitude larger uncorrelated photonic noise. The novel SPDC-based interferometric method presented here is anticipated to exhibit enhanced immunity to vibrations as well as to mechanical and photonic noise, compared to conventional X-ray interferometers. Therefore, this SU(1,1) X-ray interferometer should pave the way to unprecedented precision in phase measurements, with transformative implications for a wide range of applications.

Mathematical models of voltammetric experiments commonly contain a singular point value for the reversible potential, whereas experimental data for surface-confined redox-active species is often interpreted to contain thermodynamic dispersion, meaning the population of molecules on the electrode possess a distribution of reversible potential values. Large amplitude ramped Fourier Transformed Alternating Current Voltammetry (FTacV), a technique in which a sinusoidal potential-time oscillation is overlaid onto a linear potential-time ramp, is known to provide access to higher order harmonic components that are largely devoid of non-Faradaic current. Initially, a theoretical study reveals that the use of very large amplitude sinusoidal oscillations reduces the apparent effects of thermodynamic dispersion; conversely, frequency can be varied to change the sensitivity of the measurement to kinetic dispersion. Subsequently, FTacV measurements are used to probe a highly thermodynamically dispersed surface-confined ferrocene derivative attached to a glassy carbon electrode, with amplitudes ranging from 25 to 300 mV and low frequency, which minimises the impact of kinetic dispersion. The results from the experimental study validate the theoretical predictions, demonstrating that we can vary the amplitude in FTacV experiments to tune in and out of thermodynamic dispersion.

Plasmonic nanostructure arrays, designed for performance as pixels in an advanced SERS imaging device, were fabricated by gallium focused ion beam (FIB). Though the FIB is best suited for etching holes and negative structures, our previously reported simulations favor protrusions. Herein, we report on the FIB methodology to “sculpt” positive structures by “ion-blasting” away the surrounding material. Nanoprotrusions and nanoholes with different aspect ratios are compared experimentally with depth and height controlled by the dwell time. The amplitude and spectra of optical absorption and scattering from the two species are compared as a function of structure height. Measurements were performed using ASI’s model Rainbow hyperspectral camera, demonstrating the utility of hyperspectral microscopy for plasmonic imaging applications. Both the scattered and absorbed radiation display the broad peak …

The significant heterogeneity of Wilms’ tumors between different patients is thought to arise from genetic and epigenetic distortions that occur during various stages of fetal kidney development in a way that is poorly understood. To address this, we characterized the heterogeneity of alternative mRNA splicing in Wilms’ tumors using a publicly available RNAseq dataset of high-risk Wilms’ tumors and normal kidney samples. Through Pareto task inference and cell deconvolution, we found that the tumors and normal kidney samples are organized according to progressive stages of kidney development within a triangle-shaped region in latent space, whose vertices, or “archetypes,” resemble the cap mesenchyme, the nephrogenic stroma, and epithelial tubular structures of the fetal kidney. We identified a set of genes that are alternatively spliced between tumors located in different regions of latent space and found that many of these genes are associated with the Epithelial to Mesenchymal Transition (EMT) and muscle development. Using motif enrichment analysis, we identified putative splicing regulators, some of which are associated with kidney development. Our findings provide new insights into the etiology of Wilms’ tumors and suggest that specific splicing mechanisms in early stages of development may contribute to tumor development in different patients.

Structural diversity of diterpenes is mediated by the enigmatic family of diterpene synthases. The overall enzymatic contribution hereby lies in a carefully concerted chemistry of highly reactive carbocation intermediates mainly guided by aromatic and polar amino acid side chains and the pyrophosphate cofactor. To date several studies aimed to shed light on the mechanism underlining terpene synthases chemistry. Specifically, the diterpene synthase CotB2 serves as model enzyme for detailed mutagenesis studies. Here we investigate the catalytic mechanism of CotB2 variant V80L in a holistic, biochemical, structural, and computational biology approach. We were able to identify an altered product profile compared to CotB2WT for the substrates geranylgeranyl diphosphate and farnesyl diphosphate. Moreover, we solved the crystal structure, and shed further light on terpene synthase chemistry by modelling of the …

The magnetic state of an antiferromagnetic (AFM) insulator can be read and manipulated in spintronics devices using bilayers of an AFM and a conducting layer, making it useful for spintronics devices. To date, research has focused on single crystals of AFMs, which enables the study of properties related to different crystallographic surfaces. However, combining single-crystal AFMs in spintronics devices may be problematic due to substrate selectivity and deposition conditions. In this work, we study the properties of polycrystalline Fe 2 O 3 coupled with Pt as the conducting layer, asking how the magnetoresistive behavior differs in polycrystalline AFMs. We report on the angle dependent magnetoresistance and transverse magnetoresistance properties as a function of temperature and magnetic fields, comparing Fe 2 O 3/Pt and Fe 2 O 3/Cu/Pt thin films, in addition to magnetometry and structural characterization …

The invention of X-ray interferometers has led to advanced phase-sensing devices that are invaluable in various applications. These include the precise measurement of universal constants, e.g. the Avogadro number, of lattice parameters of perfect crystals, and phase-contrast imaging, which resolves details that standard absorption imaging cannot capture. However, the sensitivity and robustness of conventional X-ray interferometers are constrained by factors, such as fabrication precision, beam quality, and, importantly, noise originating from external sources or the sample itself. In this work, we demonstrate a novel X-ray interferometric method of phase measurement with enhanced immunity to various types of noise, by extending, for the first time, the concept of the SU(1,1) interferometer into the X-ray regime. We use a monolithic silicon perfect crystal device with two thin lamellae to generate correlated photon pairs via spontaneous parametric down-conversion (SPDC). Arrival time coincidence and sum-energy filtration allow a high-precision separation of the correlated photon pairs, which carry the phase information from orders-of-magnitude larger uncorrelated photonic noise. The novel SPDC-based interferometric method presented here is anticipated to exhibit enhanced immunity to vibrations as well as to mechanical and photonic noise, compared to conventional X-ray interferometers. Therefore, this SU(1,1) X-ray interferometer should pave the way to unprecedented precision in phase measurements, with transformative implications for a wide range of applications.

Topological superconductivity is a promising concept for generating fault-tolerant qubits. Early experimental studies looked at hybrid systems and doped intrinsic topological or superconducting materials at very low temperatures. However, higher critical temperatures are indispensable for technological exploitation. Recent angle-resolved photoemission spectroscopy results have revealed that superconductivity in the type-I Weyl semimetal—trigonal PtBi2 (t-PtBi2)—is located at the Fermi-arc surface states, which renders the material a potential candidate for intrinsic topological superconductivity. Here we show, using scanning tunnelling microscopy and spectroscopy, that t-PtBi2 presents surface superconductivity at elevated temperatures (5 K). The gap magnitude is elusive: it is spatially inhomogeneous and spans from 0 to 20 meV. In particular, the large gap value and the shape of the quasiparticle excitation …

Lytic replication is essential for persistent infection of Kaposi’s sarcoma-associated herpesvirus (KSHV) and the pathogenesis of related diseases, and many cellular pathways are hijacked by KSHV proteins to initiate and control the lytic replication of this virus. However, the mechanism involved in KSHV lytic replication from the early to the late phases remains largely undetermined. We previously revealed that KSHV open reading frame 45 (ORF45) plays important roles in late transcription and translation. In the present study, we revealed that the Forkhead box proteins FoxK1 and FoxK2 are ORF45-binding proteins and are essential for KSHV lytic gene expression and virion production, and that depletion of FoxK1 or FoxK2 significantly suppresses the expression of many late viral genes. FoxK1 and FoxK2 directly bind to the promoters of several late viral genes, ORF45 augments the promoter binding and …

Recent progress has boosted the resolving power of optical microscopies to spatial dimensions well below the diffraction limit. Yet, axial super-resolution and axial single-molecule localisation typically require more complicated implementations than their lateral counterparts. In the present work, we propose a simple solution for axial metrology by providing a multi-layered single-excitation, dual-emission test slide, in which axial distance is colour-encoded. Our test slide combines on a standard microscope coverslip substrate two flat, thin, uniform and brightly emitting fluorophore layers, separated by a nanometric transparent spacer layer having a refractive index close to a biological cell. The ensemble is sealed in an index-matched protective polymer. As a proof-of-principle, we estimate the light confinement resulting from evanescent-wave excitation in total internal reflection fluorescence (TIRF) microscopy. Our test sample permits, even for the non-expert user, a facile axial metrology at the sub-100-nm scale, a critical requirement for axial super-resolution, as well as near-surface imaging, spectroscopy and sensing.

Natural and anomalous diffusion are widely observed and used to explore causes and consequences of movement across organisms, resulting in extensive use of the mean and mean-squared displacement (MSD). Using high-resolution data from over 70 million localizations of young and adult free-ranging Barn Owls (\textit{Tyto alba}), we demonstrate the necessity of a broad spectrum of displacement moments to characterize bird movement across scales. The mean and MSD -- interchangeable with moments and 2 -- are insufficient special cases. We reveal empirical strong anomalous diffusion as a nonlinear growth of displacement moments according to . The moment spectrum function displays piecewise linearity with a critical moment marking the crossover point between two scaling regimes, linked to a combination of age-specific behavioral modes. A critical timescale of five minutes marks an unexpected transition from a convex to a concave , related to environmental and behavioral constraints. Using two stochastic models of varying ecological complexity, we demonstrate that strong anomalous diffusion may be widespread in animal movement, underscoring the importance of expanding analysis beyond the average and MSD.

The development of efficient electrolytes is crucial for advancing magnesium (Mg) batteries, which hold promise for next-generation energy storage systems. Previously, electrolytes such as [Mg2(µ-Cl)3•6THF]+ [Ph4Al]-, A, and [Mg2(µ-Cl)3•6THF]+ [Ph3AlCl]-, B, have been studied, but their performance has been limited by issues related to ion dissociation and electrochemical stability. In this study, we report the synthesis of novel electrolytes by introducing polydentate ligands to these known systems, leading to the formation of [DME•MgCl•3THF]+ [Ph4Al]- 1 and [DG•MgCl•2THF]+ [Ph4Al]- 2, [Mg•3DME]2+ [Ph3AlCl-]2 3 and [Mg•2DG]2+ [Ph3AlCl-]2 4. These firstly discovered compounds were thoroughly characterized using X-ray crystallography and NMR spectroscopy. Our findings reveal that the choice of counter anion plays a pivotal role in the products and mechanism of the dissociation of the bridged [Mg2(µ-Cl)3•6THF]+ cation upon the addition of polydentate ligands. Specifically, with the [Ph4Al]- counter anion (precursor A), the dissociation results in a [MgCl]+ mono-cation, while with the [Ph3AlCl]- counter anion (precursor B), a [Mg]2+ divalent cation is formed. The resultant MgCl2 byproduct enhances solubility, expands electrochemical windows, and improves cyclic stability, leading to superior electrochemical performance of the new electrolytes (1, 2, 3, and 4) compared to the original precursors. These insights offer valuable guidelines for the design and synthesis of advanced electrolytes for rechargeable magnesium batteries, potentially paving the way for more efficient and stable energy storage solutions.

The closed topology of spherical crystals renders the presence of topological defects inevitable. These defects can organize in a plethora of different structures, such as “clouds” or grain boundary “scars”, challenging for theoretical modeling and experimental visualization. Visualizing the defects by fluorescent dye adsorption, we reveal ion concentration control of a clouds-to-scars transition, which we attribute to commonly neglected defects' core energy. The consequent line tension energy probes the defects' molecular scale energetics, enabling pattern tuning for future applications.

The formation of stable interphases on the electrodes is crucial for rechargeable lithium (Li) batteries. However, next-generation high-energy batteries face challenges in controlling interphase formation due to the high reactivity and structural changes of electrodes, leading to reduced stability and slow ion transport, which accelerate battery degradation. Here, we report an approach to address these issues by introducing multicomponent grain-boundary-rich interphase that boosts the rapid transport of ions and enhances passivation toward prolonged lifespan. This is guided by fundamental principles of solid-state ionics and geological crystallization differentiation theory, achieved through improved solvation chemistry. Demonstrations showcase how the introduction of the interphase substantially impacts the Li-ion transport across the interphase and the electrode–electrolyte compatibility in cost-effective electrolyte …

The development of efficient electrolytes is crucial for advancing magnesium (Mg) batteries, which hold promise for next-generation energy storage systems. Previously, electrolytes such as [Mg2(µ-Cl)3•6THF]+ [Ph4Al]-, A, and [Mg2(µ-Cl)3•6THF]+ [Ph3AlCl]-, B, have been studied, but their performance has been limited by issues related to ion dissociation and electrochemical stability. In this study, we report the synthesis of novel electrolytes by introducing polydentate ligands to these known systems, leading to the formation of [DME•MgCl•3THF]+ [Ph4Al]- 1 and [DG•MgCl•2THF]+ [Ph4Al]- 2, [Mg•3DME]2+ [Ph3AlCl-]2 3 and [Mg•2DG]2+ [Ph3AlCl-]2 4. These firstly discovered compounds were thoroughly characterized using X-ray crystallography and NMR spectroscopy. Our findings reveal that the choice of counter anion plays a pivotal role in the products and mechanism of the dissociation of the bridged [Mg2(µ-Cl)3•6THF]+ cation upon the addition of polydentate ligands. Specifically, with the [Ph4Al]- counter anion (precursor A), the dissociation results in a [MgCl]+ mono-cation, while with the [Ph3AlCl]- counter anion (precursor B), a [Mg]2+ divalent cation is formed. The resultant MgCl2 byproduct enhances solubility, expands electrochemical windows, and improves cyclic stability, leading to superior electrochemical performance of the new electrolytes (1, 2, 3, and 4) compared to the original precursors. These insights offer valuable guidelines for the design and synthesis of advanced electrolytes for rechargeable magnesium batteries, potentially paving the way for more efficient and stable energy storage solutions.

Rechargeable manganese batteries hold promise for large-scale energy storage due to the abundance and eco-friendly nature of manganese. A key challenge is developing cathode materials capable of reversibly inserting Mn ions with a high specific capacity. Here, we demonstrate that perylene-3,4,9,10-tetracarboxylic dianhydride electrodes efficiently and reversibly insert Mn2+ ions in 3 M MnCl2 aqueous electrolyte solutions. Leveraging the carbonyl groups and the π-electron configuration, such compounds can serve as robust redox centers, facilitating reversible interactions with divalent ions such as Mn2+. Through comprehensive studies involving electrochemistry, elemental analyses, spectroscopy, and structural analysis, we explored these systems and found them as promising anode materials for Mn batteries. Demonstrating excellent Mn storage capabilities, such molecules could attain a reversible …

Digital holographic microscopy (DHM) is a very popular interferometric technique for quantitative phase imaging (QPI). In DHM, an interferometer is combined with a microscope to create interference between an imaging beam containing information about the analysed sample and a clear reference beam carrying no sample information. To exploit the capability of reference beam in terms of useful sample information, we have recently proposed Cepstrum-based Interferometric Microscopy (CIM) [Opt. Las. Tech. 174, 110,626 (2024)] as a novel methodology involving the interference of two imaging beams carrying different sample information and to accurately retrieve quantitative phase data of both beams. In the earlier implementation, proof-of-concept of CIM was demonstrated for a Michelson-based layout requiring manual adjustments during the CIM methodology and validated only for low numerical aperture (NA …

Li‐ion batteries based on high specific capacity LixSiO‐Graphite anodes and LiNi0.89Co0.05 Mn0.05Al0.01O2 (NCMA) cathodes may have numerous practical applications owing to high energy density without a necessary compromise on safety. SiO, which is an attractive Li insertion anode material, offers more cycling stability than Si and a higher capacity than graphite. Therefore, a new trend has emerged for developing composite C‐Si anodes, possessing the excellent cyclability of graphite coupled with high capacity SiO. The composite structure described herein prevents the volume expansion of SiO and maintains the structural integrity during prolonged cycling. However, graphite electrodes suffer from exfoliation in propylene carbonate (PC) based electrolyte solutions, which avoids well known safety benefits related to a possible use of PC based electrolyte solutions in all kinds of Li batteries. Herein, it is …

Magnesium-ion batteries (MIBs) are promising candidates for lithium-ion batteries because of their abundance, non-toxicity, and favorable electrochemical properties. This review explores the reaction mechanisms and electrochemical characteristics of Mg-alloy anode materials. While Mg metal anodes provide high volumetric capacity and dendrite-free electrodeposition, their practical application is hindered by challenges such as sluggish Mg²⁺ ion diffusion and electrolyte compatibility. Alloy-type anodes that incorporate groups XIII, XIV, and XV elements have the potential to overcome these limitations. We review various Mg alloys, emphasizing their alloying/dealloying reaction mechanisms, their theoretical capacities, and the practical aspects of MIBs. Furthermore, we discuss the influence of the electrolyte composition on the reversibility and efficiency of these alloy anodes. Emphasis is placed on overcoming …

Topological nanophotonics presents the potential for cutting-edge photonic systems, with a core aim revolving around the emergence of topological edge states. These states are primed to propagate robustly while embracing deep subwavelength confinement that defies diffraction limits. Such attributes make them particularly appealing for nanoscale applications, where achieving these elusive states has remained challenging. We unveil the first experimental proof of deep subwavelength topological edge states by implementing periodic modulation of hyperbolic phonon polaritons within a Van der Waals heterostructure. This finding represents a significant milestone in the field of nanophotonics, and it can be directly extended to and hybridized with other Van der Waals materials in various applications. The extensive scope for material substitution facilitates broadened operational frequency ranges, streamlined integration of diverse polaritonic materials, and compatibility with electronic and excitonic systems.