BINA

The nanoscale structure of equimolar binary mixtures [C 12 mim] 0.5 [C n mim] 0.5 [NTf 2] was studied by small-angle X-ray scattering for n= 1-22 and T= 293-373 K. All mixtures exhibit local layering and layer-normal thermal contraction with increasing T, as found for the pure components. The layer-parallel spacings of the polar headgroups and of the alkyl chains vary minimally with n over the full n range. The layer-normal spacing d I at high n follows closely, with a 1–1.5 Å downshift, the increasing trend of the pure longer component’s d I, indicating its dominance of the layering. At low n, d I at n= 1 greatly exceeds d I of the pure longer component, n= 12, and decreases sharply with increasing n, indicating a structure akin to lipid bilayer solutions. At intermediate n, d I is roughly constant, lying 1–1.5 Å below d I of n= 12. Our layer spacings provide a near-unique opportunity to study the evolution over a wide n-range …

Fog accumulation on surfaces typically has a negative effect by reducing their transparency and efficiency. Applications such as plastic packaging, agricultural films, and particularly many optical devices suffer from these negative effects. One way to prevent fogging is to coat the substrate with an antifogging coating having a smooth surface and hydrophilic surface chemical groups. This causes the fog water droplets that come into contact with the substrate to completely flatten across its surface, thus retaining transparency. These coatings are mostly relegated to laboratory research due to their insufficient stability and costly synthetic processes. We proposed the use of organically modified silica particles consisting of a mixture of tetraethyl orthosilicate and methacryloxypropyltriethoxysilane, which were grown in situ in the presence of a corona-activated polyethylene film, thus providing a thin siloxane coating …

The immune system matures throughout childhood to achieve full functionality in protecting our bodies against threats. The immune system has a strong reciprocal symbiosis with the host bacterial population and the two systems co-develop, shaping each other. Despite their fundamental role in health physiology, the ontogeny of these systems is poorly characterized. In this study, we investigated the development of the BCR repertoire by analyzing high-throughput sequencing of their receptors in several time points of young C57BL/6J mice. In parallel, we explored the development of the gut microbiome. We discovered that the gut IgA repertoires change from birth to adolescence, including an increase in CDR3 lengths and somatic hypermutation levels. This contrasts with the spleen IgM repertoires that remain stable and distinct from the IgA repertoires in the gut. We also discovered that large clones that germinate …

Magnesium ion (Mg2+) is one of the most significant cations in living systems with involvement in many biochemical reactions and cellular processes and hence, sensitive and specific detection of Mg2+ is therefore essential for various applications. Here, we report the solvothermal synthesis of boron‐doped carbon dots (BC10) with more oxygen surface states by using salicylaldehyde and naphthalene‐1‐boronic acid. The as‐prepared BC10 showed greenish‐white luminescence under 365 nm UV illumination with quantum yield (QY) of 5.5 % at optimum dilution with dimethyl sulfur oxide (DMSO) solvent. The BC10 in DMSO (DS‐BC10) have shown high selectivity and sensitivity towards Mg2+ ion through the increased PL intensity due to chelation‐enhanced photoluminescence (CHEP). The enhanced PL intensity was further supported by the increased QY by a factor of 12 after the addition of Mg2+ ions to 65 …

The interest in nanomaterials resides in the fact that they can be used to create smaller, faster, and more portable systems. Nanotechnology is already transforming health care. Nanoparticles are being used by scientists to target malignancies, improve drug delivery systems, and improve medical imaging. Integration of biomolecular logic gates with nanostructures has opened new paths in illness detection and therapy that need precise control of complicated components. Most studies have used fluorescence intensity techniques to implement the logic function. Its drawbacks, mainly when working with nanoparticles in intracellular media, include fluctuations in excitation power, fluorophore concentration dependence, and interference from cell autofluorescence. We suggest using fluorescence lifetime imaging microscopy (FLIM) in order to circumvent these constraints. Designing a nanohybrid composed of gold …

The spectra of Brillouin scattering processes in optical fibers are affected by temperature, axial strain, and other quantities of interest. This dependence forms the basis for optical Brillouin scattering based optical fiber sensors. Since the first proposition of such sensors in 1989, several protocols have been established for the spatially distributed analysis of Brillouin scattering spectra along fibers installed in structures of interest. Sensor systems cover hundreds of kilometers, reach sub-millimeter resolution, follow dynamic vibrations at MHz rates, and resolve sub-degree temperature changes and micro-strain elongations. Optical fiber sensors represent the most successful commercial application of Brillouin scattering physics to-date. This chapter reviews the principles, state of the art, performance trade-offs and recent breakthroughs in Brillouin scattering-based optical fiber sensors.

We present our current understanding of various aspects of Efimov physics originating from the complex multichannel hyperfine structure and overlap of Feshbach resonances for 7Li atoms. This further help us to explain puzzling experimental observations with ultracold gases. We have characterized the energies of Efimov states and corresponding interference and resonance scattering phenomena associated to them as a function of an external magnetic field. Our results also indicate that Efimov states in the 7Li system can have a unique mixed hyperfine character which strongly affect their near-threshold behavior for repulsive interatomic interactions.[1] Y. Yudkin, R. Elbaz, L. Khaykovich, arXiv: 2004.02723.

We present a novel method that we call FAINE, fast artificial intelligence neutron detection system. FAINE automatically classifies tracks of fast neutrons on CR-39 detectors using a deep learning model. This method was demonstrated using a LANDAUER Neutrak® fast neutron dosimetry system, which is installed in the External Dosimetry Laboratory (EDL) at Soreq Nuclear Research Center (SNRC). In modern fast neutron dosimetry systems, after the preliminary stages of etching and imaging of the CR-39 detectors, the third stage uses various types of computer vision systems combined with a manual revision to count the CR-39 tracks and then convert them to a dose in mSv units. Our method enhances these modern systems by introducing an innovative algorithm, which uses deep learning to classify all CR-39 tracks as either real neutron tracks or any other sign such as dirt, scratches, or even cleaning remainders. This new algorithm makes the third stage of manual CR-39 tracks revision superfluous and provides a completely repeatable and accurate way of measuring either neutrons flux or dose. The experimental results show a total accuracy rate of 96.7% for the true positive tracks and true negative tracks detected by our new algorithm against the current method, which uses computer vision followed by manual revision. This algorithm is now in the process of calibration for both alpha-particles detection and fast neutron spectrometry classification and is expected to be very useful in analyzing results of proton-boron11 fusion experiments. Being fully automatic, the new algorithm will enhance the quality assurance and effectiveness of external dosimetry, will lower the uncertainty for the reported dose measurements, and might also enable lowering the system’s detection threshold.

The pathogen Bordetella pertussis uses a type-3 secretion system (T3SS) to inject its cytotoxic effector BteA into the host cell via a designated needle structure. Prior to injection BteA is bound to its cognate chaperone BtcA presumed to assist in effector unfolding en route to needle passage. We utilized NMR and EPR spectroscopy to uncover the molecular mechanism of BtcA-mediated unfolding of BteA. BtcA induces a global structural change in the effector, which adopts a more extended and partially unfolded conformation. EPR distance measurements further show that the structured helical-bundle form of free BteA exists in conformational equilibrium with a lowly populated minor species. The nature of this equilibrium was probed using NMR relaxation dispersion experiments. At 283 K structural effects are most pronounced for a contiguous surface spanning the A- and B-helices of BteA, extending at 303 K to a …

As battery technologies are in continuous development, and especially due to the rapid growth in vehicle electrification, which requires large (e.g., 100 s of kg) battery packs, there has been a growing demand for more efficient, reliable, and environmentally friendly materials. Solid-state post-lithium-ion batteries are considered a possible next-generation energy storage technology. One immediate advantage of these power sources over commercial lithium-ion batteries is the potential of solving the resource issues facing LIBs, especially as cost-effective alternatives. The second advantage is the removal of flammable liquid electrolytes. The solid electrolytes are more resistant to changes in temperature and physical damage, produce up to 80% less heat, and are able to handle more charge/discharge cycles before degradation makes them unusable. All these features point towards a longer battery life. Other …

Magnesium ion (Mg2+) is one of the most significant cations in living systems with involvement in many biochemical reactions and cellular processes and hence, sensitive and specific detection of Mg2+ is therefore essential for various applications. Here, we report the solvothermal synthesis of boron‐doped carbon dots (BC10) with more oxygen surface states by using salicylaldehyde and naphthalene‐1‐boronic acid. The as‐prepared BC10 showed greenish‐white luminescence under 365 nm UV illumination with quantum yield (QY) of 5.5 % at optimum dilution with dimethyl sulfur oxide (DMSO) solvent. The BC10 in DMSO (DS‐BC10) have shown high selectivity and sensitivity towards Mg2+ ion through the increased PL intensity due to chelation‐enhanced photoluminescence (CHEP). The enhanced PL intensity was further supported by the increased QY by a factor of 12 after the addition of Mg2+ ions to 65 …

We present our current understanding of various aspects of Efimov physics originating from the complex multichannel hyperfine structure and overlap of Feshbach resonances for 7Li atoms. This further help us to explain puzzling experimental observations with ultracold gases. We have characterized the energies of Efimov states and corresponding interference and resonance scattering phenomena associated to them as a function of an external magnetic field. Our results also indicate that Efimov states in the 7Li system can have a unique mixed hyperfine character which strongly affect their near-threshold behavior for repulsive interatomic interactions.[1] Y. Yudkin, R. Elbaz, L. Khaykovich, arXiv: 2004.02723.

Nanomedicine constantly broadens horizons of modern therapy and diagnostics. However, imaging nanoagents are of especial interest. Here, we report on novel, facile, and sustainable way to fabricate targeted multimodal imaging nanoparticles. Specifically, we synthesize nanoparticles using immunoglobulins and introduce nanoparticles of different nature into immunoglobulin-based matrix. We demonstrate applicability of the nanoparticles both in vitro and in vivo.

Background Inflammatory myopathies (IM) are a heterogeneous group of disorders characterized by autoimmune inflammatory destruction of skeletal muscles. It is many times associated with lung, skin and joint involvement. Identifying biomarkers that can differentiate IM from other muscle disorders may elucidate the pathophysiology of IM, guide novel therapies, monitor disease activity/response to treatments and predict prognosis. Exosomes are membrane-bound nanovesicles with diameters of 30-150 nm that contain multiple proteins, nucleic acid, lipids and other molecules in a tissue- and cell-specific manner. Exosomes are secreted by a large variety of cells, play major roles in cell-cell interactions, and have recently emerged as circulating biomarkers in a variety of pathological conditions, including several autoimmune diseases.Objectives To characterize exosomes from serum of IM patients, analyze protein …

The future of Halide Perovskites, HaPs, which are of enormous interest for light ⟷ electrical energy conversion, is beclouded by limited scientific understanding of their long‐term stability. While HaPs can be altered by absorbed radiation that induces multiple processes, remarkably, they can also return to their original state by “self‐healing”. Here we use 2‐photon absorption to effect light‐induced modifications within single crystals of MAPbI3, the prototypical HaP. We then follow the changes in the photo‐damaged region by measuring the photoluminescence, resulting also from 2‐photon absorption, but with 2.5 orders of magnitude lower intensity than that used for photodamaging the MAPbI3. We find, immediately after photo‐damage, two brightening and one darkening process, all of which recover but on different timescales. The first two are attributed to trap‐filling (the fastest) and to proton‐amine related …

Dissipative solitons are fundamental wave-pulses that preserve their form in the presence of periodic loss and gain. The canonical realization of dissipative solitons is Kerr-lens mode locking (KLM) in lasers, which delicately balance nonlinear and linear propagation in both time and space to generate ultrashort optical pulses. This linear-nonlinear balance dictates a unique pulse energy, which cannot be increased (say by elevated pumping), indicating that excess energy is expected to be radiated in the form of dispersive or diffractive waves. Here we show that KLM lasers can overcome this expectation. Specifically, by breaking the spatial symmetry between the forward and backward halves of the round-trip in a linear cavity, the laser can modify the soliton in space to incorporate the excess energy. Increasing the pump power leads therefore to a different soliton solution, rather than to dispersive/diffractive loss. We predict the symmetry breaking by a complete numerical simulation of the spatio-temporal dynamics in the cavity, and confirm it experimentally in a KLM Ti: Sapphire laser with quantitative agreement to the simulation. The simulation opens a window to directly observe the nonlinear space-time dynamics that molds the soliton pulse, and possibly to optimize it.

Perovskite solar cells (PSCs) are being studied and developed because of the outstanding properties of halide perovskites as photovoltaic materials and high conversion efficiencies achieved with the best PSCs. However, leaching out of lead (Pb) ions into the environment presents potential public health risks. We show that thiol-functionalized nanoparticles provide an economic way of minimizing Pb leaching in the case of PSC module damage and subsequent water exposure (at most, ∼2.5% of today’s crystal silicon solar panel production cost per square meter). Using commercial materials and methods, we retain ∼90% of Pb without degrading the photovoltaic performance of the cells, compared with nonencapsulated devices, yielding a worst-case scenario of top-soil pollution below natural Pb levels and well below the U.S. Environmental Protection Agency limits.

Fibre lasers based on backward stimulated Brillouin scattering provide narrow linewidths and serve in signal processing and sensing applications. Stimulated Brillouin scattering in fibres takes place in the forward direction as well, with amplification bandwidths that are narrower by two orders of magnitude. However, forward Brillouin lasers have yet to be realized in any fibre platform. In this work, we report a first forward Brillouin fibre laser, using a bare off-the-shelf, panda-type polarisation maintaining fibre. Pump light in one principal axis provides Brillouin amplification for a co-propagating lasing signal of the orthogonal polarisation. Feedback is provided by Bragg gratings at both ends of the fibre cavity. Single-mode, few-modes and multi-mode regimes of operation are observed. The lasing threshold exhibits a unique environmental sensitivity: it is elevated when the fibre is partially immersed in water due to the …