Sodium Biphenyl as Anolyte for Sodium-Seawater Batteries

Sodium-based battery systems have recently attracted increasing research interest due to the abundant resources employed. Among various material candidates for the negative electrode, sodium metal provides the highest capacity of theoretically 1165 mAh g(-1) and a very low redox potential of -2.71 versus the standard hydrogen electrode. However, the high reactivity of sodium metal toward the commonly used electrolytes results in severe side reactions, including the evolution of gaseous decomposition products, and, in addition, the risk of dendritic sodium growth, potentially causing a disastrous short circuit of the cell. Herein, the use of sodium biphenyl (Na-BP) as anolyte for the Na-seawater batteries (Na-SWB) is investigated. The catholyte for the open-structured positive electrode is natural seawater with sodium cations dissolved therein. Remarkably, the significant electronic and ionic conductivities of the Na-BP anolyte enable a low overpotential for the sodium deposition upon charge, allowing for high capacity and excellent capacity retention for 80 cycles in full Na-SWB. Additionally, the Na-BP anolyte suppresses gas evolution and dendrite growth by forming a homogeneous surface layer on the metallic negative electrode

uFLIP-OC: Understanding Flash I/O Patterns on Open-Channel Solid State Drives

International audienceSolid-State Drives (SSDs) have gained acceptance by providing the same block device abstraction as magnetic hard drives, at the cost of suboptimal resource utilisation and unpredictable performance. Recently, Open-Channel SSDs have emerged as a means to obtain predictably high performance, based on a clean break from the block device abstraction. Open-channel SSDs embed a minimal flash translation layer (FTL) and expose their internals to the host. The Linux open-channel SSD subsystem, LightNVM, lets kernel modules as well as user-space applications control data placement and I/O scheduling. This way, it is the host that is responsible for SSD management. But what kind of performance model should the host rely on to guide the way it manages data placement and I/O scheduling? For addressing this question we have defined uFLIP-OC, a benchmark designed to identify the I/O patterns that are best suited for a given open-channel SSD. Our experiments on a Dragon-Fire Card (DFC) SSD, equipped with the OX controller, illustrate the performance impact of media characteristics and parallelism. We discuss how uFLIP-OC can be used to guide the design of host-based data systems on open-channel SSDs

Learning Large-scale Neural Fields via Context Pruned Meta-Learning

We introduce an efficient optimization-based meta-learning technique for large-scale neural field training by realizing significant memory savings through automated online context point selection. This is achieved by focusing each learning step on the subset of data with the highest expected immediate improvement in model quality, resulting in the almost instantaneous modeling of global structure and subsequent refinement of high-frequency details. We further improve the quality of our meta-learned initialization by introducing a bootstrap correction resulting in the minimization of any error introduced by reduced context sets while simultaneously mitigating the well-known myopia of optimization-based meta-learning. Finally, we show how gradient re-scaling at meta-test time allows the learning of extremely high-quality neural fields in significantly shortened optimization procedures. Our framework is model-agnostic, intuitive, straightforward to implement, and shows significant reconstruction improvements for a wide range of signals. We provide an extensive empirical evaluation on nine datasets across multiple multiple modalities, demonstrating state-of-the-art results while providing additional insight through careful analysis of the algorithmic components constituting our method. Code is available at https://github.com/jihoontack/GradNCPComment: Published as a conference proceeding for NeurIPS 202

Localized Laser-Based Photohydrothermal Synthesis of Functionalized Metal-Oxides

We discuss the rapid in situ hydrothermal synthesis of metal oxide materials based on the photothermal superheating of light-absorbing metal layers for simple and facile on-demand placement of semiconductor materials with micrometer-scale lateral resolution. Localized heating from pulsed and focused laser illumination enables ultrafast growth of metal oxide materials with high spatiotemporal precision in aqueous precursor solution. Among many possible electronic and optoelectronic applications, the proposed method can be used for laser-based in situ real-time soldering of separated metal structures and electrodes with functionalized semiconductor materials. Resistive electrical interconnections of metal strip lines as well as sensitive UV detection using photohydrothermally grown metal oxide bumps are experimentally demonstrated

In-Plane Anisotropy and Temperature Dependence of Oxygen Phonon Modes in YBa₂Cu₃O₆.₉₅

Inelastic pulsed neutron scattering measurements on YBa2Cu3O6.95 single crystals indicate that the sample has a distinct a-b plane anisotropy in the oxygen vibrations. The Cu-O bond-stretching-type phonons, which are suspected to interact strongly with charge, are simultaneously observed along the a and b directions due to a 7-meV splitting arising from the orthorhombicity, even though the sample is twinned. The bond-stretching LO branch with the polarization along a (perpendicular to the chain) loses intensity beyond the middle of the zone, indicating branch splitting as seen in doped nickelates, with the second branch being located at 10 meV below. The mode along b has a continuous dispersion. These modes show temperature dependence, which parallels that of superconductive order parameter, suggesting significant involvement of phonons in the superconductivity of this compound

Cytosolic calcium regulates cytoplasmic accumulation of TDP-43 through Calpain-A and Importin alpha 3

Cytoplasmic accumulation of TDP-43 in motor neurons is the most prominent pathological feature in amyotrophic lateral sclerosis (ALS). A feedback cycle between nucleocytoplasmic transport (NCT) defect and TDP-43 aggregation was shown to contribute to accumulation of TDP-43 in the cytoplasm. However, little is known about cellular factors that can control the activity of NCT, thereby affecting TDP-43 accumulation in the cytoplasm. Here, we identified via FRAP and optogenetics cytosolic calcium as a key cellular factor controlling NCT of TDP-43. Dynamic and reversible changes in TDP-43 localization were observed in Drosophila sensory neurons during development. Genetic and immunohistochemical analyses identified the cytosolic calcium-Calpain-A-Importin α3 pathway as a regulatory mechanism underlying NCT of TDP-43. In C9orf72 ALS fly models, upregulation of the pathway activity by increasing cytosolic calcium reduced cytoplasmic accumulation of TDP-43 and mitigated behavioral defects. Together, these results suggest the calcium-Calpain-A-Importin α3 pathway as a potential therapeutic target of ALS. © Park et al.1

Identification of a dysfunctional exon-skipping splice variant in GLUT9/SLC2A9 causal for renal hypouricemia type 2

Renal hypouricemia (RHUC) is a pathological condition characterized by extremely low serum urate and overexcretion of urate in the kidney; this inheritable disorder is classified into type 1 and type 2 based on causative genes encoding physiologically-important urate transporters, URAT1 and GLUT9, respectively; however, research on RHUC type 2 is still behind type 1. We herein describe a typical familial case of RHUC type 2 found in a Slovak family with severe hypouricemia and hyperuricosuria. Via clinico-genetic analyses including whole exome sequencing and in vitro functional assays, we identified an intronic GLUT9 variant, c.1419+1G>A, as the causal mutation that could lead the expression of p.Gly431GlufsTer28, a functionally-null variant resulting from exon 11 skipping. The causal relationship was also confirmed in another unrelated Macedonian family with mild hypouricemia. Accordingly, non-coding regions should be also kept in mind during genetic diagnosis for hypouricemia. Our findings provide a better pathogenic understanding of RHUC and pathophysiological importance of GLUT9