BINA

Opto-electronic oscillators are sources of microwave-frequency tones that may reach very low noise levels. Much effort is being dedicated to the realization of oscillators based on photonic integrated devices. In this work, we propose and demonstrate a thermo-elastic opto-electronic oscillator at 2.213 GHz frequency based on a standard silicon-photonic integrated circuit. A microwave-frequency electrical signal modulates an optical pump wave carrier. The modulated waveform launches surface acoustic waves in a silicon-on-insulator substrate, through absorption in a metallic grating and thermo-elastic actuation. The waveform is reconverted to the optical domain through photoelastic modulation of an optical probe wave carrier in a standard racetrack resonator waveguide. Both the thermo-elastic actuation and the photoelastic modulation are radio-frequency selective. The output probe wave is detected, and the receiver voltage is amplified and fed back to modulate the optical pump input. Sufficient gain drives the loop into oscillations. The oscillator does not involve piezoelectricity and can be realized on any substrate. Long acoustic delays may be implemented in compact devices. The frequency of operation is scalable to tens of GHz. The principle may be useful in integrated microwave-photonic signal processing and in the elastic analysis of surfaces and thin layers.

Efficient and stable electrocatalysts are critically needed for the development of practical overall seawater splitting. The nanocomposite of RuCoBO has been rationally engineered to be an electrocatalyst that fits these criteria. The study has shown that a calcinated RuCoBO-based nanocomposite (Ru2Co1BO-350) exhibits an extremely high catalytic activity for H2 and O2 production in alkaline seawater (overpotentials of 14 mV for H2 evolution and 219 mV for O2 evolution) as well as a record low cell voltage (1.466 V@10 mA cm–2) and long-term stability (230 h @50 mA cm–2 and @100 mA cm–2) for seawater splitting. The results show that surface reconstruction of Ru2Co1BO-350 occurs during hydrogen evolution reaction and oxygen evolution reaction, which leads to the high activity and stability of the catalyst. The reconstructed surface is highly resistant to Cl– corrosion. The investigation suggests that a new …

The term “carbon-based spintronics” mostly refers to the spin applications in carbon materials such as graphene, fullerene, carbon nitride, and carbon nanotubes. Carbon-based spintronics and their devices have undergone extraordinary development recently. The causes of spin relaxation and the characteristics of spin transport in carbon materials, namely for graphene and carbon nanotubes, have been the subject of several theoretical and experimental studies. This article gives a summary of the present state of research and technological advancements for spintronic applications in carbon-based materials. We discuss the benefits and challenges of several spin-enabled, carbon-based applications. The advantages include the fact that they are significantly less volatile than charge-based electronics. The challenge is in being able to scale up to mass production.

[(LiNi0·8Co0·1Mn0.1)O2], or NCM811, a member of the LixNi1−y−zCoyMnzO2 (NCM) family of cathode active materials (CAMs), is gaining recognition in the battery community as the CAM of choice for future high energy density lithium-ion batteries, given its high nickel content of c. 80%. Yet, its commercialization is impeded by its mechanochemical instability at a high state of charge (SOC), which results in severe capacity fading and active lithium loss during cycling. In this contribution, we report conformal nanometer-thick (c. 4–7 nm) lithiated tin-oxide ternary coatings (LixSnyOz) deposited on NCM811 cathode powder using the atomic layer deposition (ALD) technique. The first-of-its-kind ALD coating, where Li is being accompanied by a second metal ion (Sn); provides a combination of benefits: (i) it stabilizes the crystal structure, (ii) suppresses electrode polarization, (iii) lowers the voltage hysteresis, and (iv …

PROCEEDINGS OF SPIE Page 1 PROCEEDINGS OF SPIE SPIEDigitalLibrary.org/conference-proceedings-of-spie Front Matter: Volume 12394 , "Front Matter: Volume 12394," Proc. SPIE 12394, Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XX, 1239401 (2 May 2023); doi: 10.1117/12.2678752 Event: SPIE BiOS, 2023, San Francisco, California, United States Downloaded From: https://www.spiedigitallibrary.org/conference-proceedings-of-spie on 03 May 2023 Terms of Use: https://www.spiedigitallibrary.org/terms-of-use Page 2 PROGRESS IN BIOMEDICAL OPTICS AND IMAGING Vol. 24 No. 43 Volume 12394 Proceedings of SPIE, 1605-7422, V. 12394 SPIE is an international society advancing an interdisciplinary approach to the science and application of light. Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XX Dror Fixler Ewa M. Goldys Sebastian Wachsmann-…

Wilms’ tumors are pediatric malignancies that are thought to arise from faulty kidney development. They contain a wide range of poorly differentiated cell states resembling various distorted developmental stages of the fetal kidney, and as a result, differ between patients in a continuous manner that is not well understood. Here, we used three computational approaches to characterize this continuous heterogeneity in high-risk blastemal-type Wilms’ tumors. Using Pareto task inference, we show that the tumors form a triangle-shaped continuum in latent space that is bounded by three tumor archetypes with “stromal”,“blastemal”, and “epithelial” characteristics, which resemble the un-induced mesenchyme, the cap mesenchyme, and early epithelial structures of the fetal kidney. By fitting a generative probabilistic “grade of membership” model, we show that each tumor can be represented as a unique mixture of three hidden “topics” with blastemal, stromal, and epithelial characteristics. Likewise, cellular deconvolution allows us to represent each tumor in the continuum as a unique combination of fetal kidney-like cell states. These results highlight the relationship between Wilms’ tumors and kidney development, and we anticipate that they will pave the way for more quantitative strategies for tumor stratification and classification.

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.

The cover feature image illustrates two sites of a protein with different site specific reorientational dynamics (purple). Such differences can be measured by newly developed site-directed Cu (II) labeling methodology. The resultant EPR lineshape at physiological temperatures is sensitive to the timescale of backbone motion. Importantly, this methodology enables site-specific detection on both α-helices and β-sheets via EPR. Thus, the role of protein dynamics to protein function can be elucidated. More information can be found in the Review by Sunil Saxena and co-workers.

Second harmonic generation (SHG) is forbidden for centrosymmetric materials such metals. Yet, symmetry can be broken by introducing plasmonic nano-structures which lead to enhancement of the electromagnetic field at both the fundamental and the SH frequencies. Using non-linear microscopy, we experimentally demonstrate enhanced SHG from isosceles triangular cavities (~215 nm side length, 200 nm base) milled in thin aluminum film. Upon strong interaction between the cavities, they behave as a single unit and response in a coherent manner, i.e. SHG is observed from the coupled system. The hybridization between the cavities is not only dependent on the distance between them, but their spatial arrangement is found to be a crucial parameter. That is, the SHG efficiency can be enhanced upon different arrangement of the same cavities, holding the same distance between them. We characterize those …

Nanoporous metallic systems exhibit a new generation of advanced materials with potential in a wide variety of technological fields among them catalysis, photonics, optoelectronics and sensors.Their high surface-to-volume ratio, multimodal nanoscale moieties, ability to host guest materials, and inhomogeneous surface at the submicron scale distinct them from both bulk metals and conventional plasmonic materials as well as meta-surfaces. Those structures can be prepared through different fabrication and synthesis strategies including chemical dealloying, assembly of pre-synthesized metallic nanoparticles, and via templating. In a sharp contrast with these preparation strategies, we have demonstrated one can fabricate a macroscopic nanopourus metallic networks by using physical vapor deposition in a short single-step process. These materials are highly pure, and they show very unique linear and non-linear …

{Velocity map imaging (VMI) is a powerful technique that allows to infer the kinetic energy of ions or electrons that are produced from a large volume in space with good resolution. The size of the acceptance volume is determined by the spherical aberrations of the ion optical system. Here we present an analytical derivation for velocity map imaging with no spherical aberrations. We will discuss a particular example for the implementation of the technique that allows using the reaction microscope recently installed in the Cryogenic storage ring (CSR) in a VMI mode. SIMION simulations confirm that a beam of electrons produced almost over the entire volume of the source region, with width of 8 cm, can be focused to a spot of 0.1 mm on the detector. The use of the same formalism for position imaging, as well as an option of position imaging in one axis and velocity map imaging in a different axis, are also discussed.

Although non-alkaline rechargeable Zn-air batteries (RZABs) are promising for energy storage, their chemistry is still underdeveloped and unclear. It was suggested that using Zn(OAc)2 or Zn(OTf)2 aqueous solutions as electrolytes enables reversible, corrosion-free charge-discharge proccesses, but anodic stability of carbon in these cells has remained poorly studied. We report that CO2 evolution is manifested during oxygen evolution reaction in non-alkaline RZABs, which is associated with corrosion of carbon scaffolds. This corrosion is observed for different electrolyte compositions, such as Zn(OAc)2, ZnSO4 and Zn(OTf)2 solutions of various concentrations. The corrosion rate decreases when the overpotentials during oxygen evolution reaction are lower. This study underlines the importance of addressing the anodic instability of carbon in non-alkaline RZABs.

The glass transition temperature is a key parameter of polymer coating layers that protect optical fibers, and it affects the proper function of the fibers in their service environment. Established protocols for glass transition temperature measurements are destructive, require samples of specific geometries, and may only be carried out offline. In this work, we report the non-destructive measurement of the glass transition temperature of an acrylate polymer coating layer over a working standard fiber. The method is based on forward stimulated Brillouin scattering. Large decrease in the modulus of the coating layer above the glass transition temperature manifests in narrowing of the modal linewidths in the forward Brillouin scattering spectrum. The transition temperature agrees with standard dynamic mechanical analysis of samples made of the same polymer. The protocol can be useful for coating materials research and …

The realization of lithium-oxygen (Li-O2) batteries has been impeded by parasitic reactions that cause cell component degradation, often accompanied by the release of CO2 gas during oxidation reactions. The use of halide-based redox mediators (RMs) like LiBr and LiI has been proposed as a strategy to reduce overpotentials during oxygen evolution reactions and thus suppress the subsequent evolution of CO2. However, there is a scarcity of research examining the effectiveness of these RMs in the direct mitigation of parasitic reactions. In this study, we investigated the evolution of CO2 during the oxidation processes using an online electrochemical mass spectrometer. The results show that cells without RMs exhibited high overpotentials and significant CO2 evolution from the first charging cycle. In contrast, the addition of 50mM LiI to the electrolyte resulted in a delay in CO2 evolution, observed only after several …

EPR in-cell spin-labeling was applied to CueR in E. coli. The methodology employed a Cu(II)-NTA complexed with dHis. High resolved in-cell distance distributions were obtained revealing minor differences between in-vitro and in-cell data. This methodology allows to study structural changes of any protein in-cell, independent of size or cellular system

Samples of H6TPPS J aggregates and bundles, deposited on glass and aligned under nitrogen flow, were measured in a 2-photon microscopy setup. Changes in the polarization state of the incoming laser have shown a difference in the resulting 2-photon scanning of the same measured sample, revelling otherwise hidden features. In addition, tracing the response of certain areas under different polarisation can provide information about the arrangement of the dipoles in that area. This shows the significant role of polarisation in 2-photon measurement, and the need to consider such effects in the microscopy of biological samples.

Background Myocardial infarction (MI) and heart failure (HF) are associated with an increased incidence of cancer. The mechanism is complex and unclear. Here, we aimed to test our hypothesis that cardiac small extracellular vesicles (sEVs), particularly cardiac mesenchymal stromal cells-derived sEVs (cMSC-sEVs), contribute to the link between post-MI HF and cancer. Methods We purified and characterized sEVs from the whole heart and cultured cMSCs. Then, we analyzed cMSC-EV cargo and pro-neoplastic effects on several types of cancer cell lines, macrophages, and endothelial cells. Next, we modeled post-MI HF along with heterotopic and orthotopic lung and breast cancer tumors in mice. We used cMSC-sEV transfer to assess sEV biodistribution and its effect on tumor growth. Finally, we tested the effects of sEV depletion and spironolactone treatment on cMSC-EV release and tumor growth. Results Post-MI hearts, particularly cMSCs, produced more sEVs with pro-neoplastic cargo than non-failing hearts did. Proteomic analysis revealed unique protein profiles and higher quantities of tumor-promoting cytokines, proteins, and microRNAs in cMSC-sEVs from failing hearts. The pro-neoplastic effects of cMSC-sEVs varied with different types of cancer cells, substantially affecting lung cancer cells relative to other more aggressive cancer cell lines. We also found that post-MI cMSC-sEVs activated resting macrophages into pro-angiogenic and pro-tumorigenic states in vitro. At 28-day follow-up analysis, mice with post-MI HF developed larger lung tumors than did sham-MI mice. Adoptive transfer of cMSC-sEVs from failing hearts accelerated …

Climate change calls for a change in the way we use and produce energy, and carbon-free has become the future direction of energy production and utilization. To obtain this, we must rely on sustainable energy sources such as wind and sun, but their intermittence limits the production of clean energy to only a few hours a day. To overcome this issue, energy storage and production technologies must be developed. Although several technologies have been proposed, the only viable scheme that could allow short-to-long-term storage and efficient energy transportation at-scale is the hydrogen economy, which relies on three pillars of technology: electrolyzers, hydrogen storage and fuel cells. In recent years, there have been rapid technological advances in hydrogen production, new hydrogen storage materials, and high-performance hydrogen fuel cells, etc. However, there are still numerous technological difficulties …

Confocal microscopes have been the workhorses of 3-D biological imaging, but they are slow, offer limited depth penetration and collect only ballistic photons. With their inefficient use of excitation photons they expose biological samples to an often intolerably high light burden. The speed limitation and photo-bleaching risk can be somewhat relaxed in a spinning-disk geometry, due to shorter pixel dwell times and rapid re-scans during image capture. Alternatively, light-sheet microscopes rapidly image large volumes of transparent or chemically cleared samples. Finally, with infrared excitation and efficient scattered-light collection, 2-photon microscopy allows deep-tissue imaging, but it remains slow. Here, we describe a new optical scheme that borrows the best from three different worlds: the speed and direct-view from a spinning-disk confocal, deep tissue-penetration and intrinsic optical sectioning from 2-photon …

Background Parkinson disease (PD) is associated with dysbiosis, proinflammatory gut microbiome, disruptions to intestinal barrier functions, and immunological imbalance. Microbiota-produced short-chain fatty acids promote gut barrier integrity and immune regulation, but their impact on PD pathology remains mostly unknown. Objectives To evaluate supplementation with short-chain fatty acids as an add-on intervention in PD. Methods In a randomized double-blind prospective study, 72 PD patients received short-chain fatty acids and/or the prebiotic fiber 2-fucosyllactose supplementation over 6 months. Results We observed improvement in motor and nonmotor symptoms, in addition to modulation of peripheral immunity and improved mitochondrial respiration in immunocytes. The supplementation had no effect on microbiome diversity or composition. Finally, multiobjective analysis and comprehensive immunophenotyping revealed parameters associated with an optimal response to short-chain fatty acids and/or 2-fucosyllactose supplementation. Conclusion Short-chain fatty acids ameliorate clinical symptoms in Parkinson disease patients and modulate mitochondrial function and peripheral immunity.

The development of vacuum‐deposited perovskite materials and devices is partially slowed down by the minor research effort in this direction, due to the high cost of the required research tools. But there is also another factor, thermal co‐deposition in high vacuum involves the simultaneous sublimation of several precursors with an overall deposition rate in the range of few Å s−1. This leads to a deposition time of hours with only a single set of process parameters per batch, hence to a long timeframe to optimize even a single perovskite composition. Here we report the combinatorial vacuum deposition of wide bandgap perovskites using 4 sources and a non‐rotating sample holder. By using small pixel substrates, more than 100 solar cells can be produced with different perovskite absorbers in a single deposition run. The materials are characterized by spatially resolved methods, including optical, morphological …