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Single‐atom catalysts (SACs), featuring highly uniform active sites, tunable coordination environments, and synergistic effects with support, have emerged as one of the most efficient catalysts for various reactions, particularly for electrochemical CO2 reduction (ECR). However, the scalability of SACs is restricted due to the limited choice of available support and problems that emerge when preparing SACs by thermal deposition. Here, an in situ reconstruction method for preparing SACs is developed with a variety of atomic sites, including nickel, cadmium, cobalt, and magnesium. Driven by electricity, different oxygen‐containing metal precursors, such as MOF‐74 and metal oxides, are directly atomized onto nitrogen‐doped carbon (NC) supports, yielding SACs with variable metal active sites and coordination structures. The electrochemical force facilitates the in situ generation of bonds between the metal and the supports without the need for additional complex steps. A series of MNxOy (M denotes metal) SACs on NC have been synthesized and utilized for ECR. Among these, NiNxOy SACs using Ni‐MOF‐74 as a metal precursor exhibit excellent ECR performance. This universal and general SAC synthesis strategy at room temperature is simpler than most reported synthesis methods to date, providing practical guidance for the design of the next generation of high‐performance SACs. [ABSTRACT FROM AUTHOR]

The rechargeable Li–CO2 battery shows great potential in civil, military, and aerospace fields due to its high theoretical energy density and CO2 capture capability. To facilitate the practical application of Li–CO2 battery, the design of efficient, low‐cost, and robust non‐noble metal cathodes to boost CO2 reduction/evolution kinetics is highly desirable yet remains a challenge. Herein, single‐atom cadmium is reported with a Cd‐N4 coordination structure enable rapid kinetics of both the discharge and recharge process when employed as a cathode catalyst, and thus facilitates exceptional rate performance in a Li–CO2 battery, even up to 10 A g−1, and remains stable at a high current density (100 A g−1). An unprecedented discharge capacity of 160045 mAh g−1 is attained at 500 mA g−1. Excellent cycling stability is maintained for 1685 and 669 cycles at 1 A g−1 and capacities of 0.5 and 1 Ah g−1, respectively. Density functional theory calculations reveal low energy barriers for both Li2CO3 formation and decomposition reactions during the respective discharge and recharge process, evidencing the high catalytic activity of single Cd sites. This study provides a simple and effective avenue for developing highly active and stable single‐atom non‐precious metal cathode catalysts for advanced Li–CO2 batteries. [ABSTRACT FROM AUTHOR]

Separators play an essential role in lithium (Li)-based secondary batteries by preventing direct contact between the two electrodes and providing conduction pathways for Li-ions in the battery cells. However, conventional polyolefin separators exhibit insufficient electrolyte wettability and thermal stability, and in particular, they are vulnerable to Li dendritic growth, which is a significant weakness in Li-metal batteries (LMBs). To improve the safety and electrochemical performance of LMBs, Al2O3 nanoparticles and nanocellulose (NC)-coated non-woven poly(vinylidene fluoride)/polyacrylonitrile separators were fabricated using a simple, water-based blade coating method. The Al2O3/NC-coated separator possessed a reasonably porous structure and a significant number of hydroxyl groups (-OH), which enhanced electrolyte uptake (394.8%) and ionic conductivity (1.493 mS/cm). The coated separator also exhibited reduced thermal shrinkage and alleviated uncontrollable Li dendritic growth compared with a bare separator. Consequently, Li-metal battery cells with a LiNi0.8Co0.1Mn0.1O2 cathode and an Al2O3/NC-coated separator using either liquid or solid polymer electrolytes exhibited improved rate capability, cycle stability, and safety compared with a cell with a bare separator. The present study demonstrates that combining appropriate materials in coatings on separator surfaces can enhance the safety and electrochemical performance of LMBs. [ABSTRACT FROM AUTHOR]

The growing commercial interest in indoor localization-based services has stimulated the development of many indoor positioning systems. Despite extensive research on localization, system requirements, such as site survey, user intervention, or specific hardware/software, place limitations on the widespread deployment of localization. To overcome these limitations, we propose a path estimation and localization system for indoor environments, termed PYLON, that runs on a smartphone and a server without any human intervention. PYLON uses an actual floor plan and measurements from widely deployed WiFi access points (APs) and Bluetooth Low Energy (BLE) beacons to estimate the user’s path. It creates virtual rooms according to received signal strength indicator (RSSI) values and matches them to actual rooms in the real-world floor plan. After room mapping, PYLON uses door passing times to precisely refine a user’s estimated path. Unlike conventional path estimation and localization systems, PYLON works independently of device types. We implement PYLON on five Android smartphones and conduct evaluation with three users in an office building. Our experimental results show that PYLON achieves 97 percent floor plan mapping accuracy with a localization error of 1.42 m. [ABSTRACT FROM AUTHOR]

With the advent of advances in imaging and computing technologies, large-scale data acquisition and processing have become commonplace in many science and engineering disciplines. Conventional workflows for large-scale data processing usually rely on in-house or commercial software that are designed for domain-specific computing tasks. Recent advances in MapReduce, which was originally developed for batch processing textual data via a simplified programming model of the map and reduce functions, have expanded its applications to more general tasks in big-data processing, such as scientific computing, and biomedical image processing. However, as shown in previous work, volume rendering and visualization using MapReduce is still considered challenging and impractical owing to the disk-based, batch-processing nature of its computing model. In this article, contrary to this common belief, we show that the MapReduce computing model can be effectively used for interactive visualization. Our proposed system is a novel extension of Spark, one of the most popular open-source MapReduce frameworks, which offers GPU-accelerated MapReduce computing. To minimize CPU-GPU communication and overcome slow, disk-based shuffle performance, the proposed system supports GPU in-memory caching and MPI-based direct communication between compute nodes. To allow for GPU-accelerated in-situ visualization using raster graphics in Spark, we leveraged the CUDA-OpenGL interoperability, resulting in faster processing speeds by several orders of magnitude compared to conventional MapReduce systems. We demonstrate the performance of our system via several volume processing and visualization tasks, such as direct volume rendering, iso-surface extraction, and numerical simulations with in-situ visualization. [ABSTRACT FROM AUTHOR]

Background: Intramedullary hip nails may be classified as blades or screws depending on the type of lag screw used. Recently, a combination of lag screw types with a U-clip insertion has also been used. The purpose of this study was to evaluate the clinical and radiological outcomes of these new screw types. Methods: A total of 185 patients with trochanteric femoral fractures (age ≥ 65 years) who underwent surgery with intramedullary nails were selected. Surgeries with InterTrochanteric/SubTrochanteric (ITST), Proximal Femoral Nail Antirotation (PFNA), and Gamma 3 U-Blade lag screws were performed between January 2011 and June 2016. The AO/OTA classification, presence of a basicervical fracture type on 3D-CT, BMI, BMD, reduction quality, position of the lag screw, TAD (tip apex distance) of the lag screw, sliding distance of the lag screw, varus change (neck shaft angle), radiological union period, fixation failure and functional outcome as determined by walking ability were analyzed. Results: There were 3/60 (5.0%) cases of fixation failure in the ITST group, all caused by cut-out; 4/57 (7.0%) in the PFNA II group: 3 caused by cut-through and 1 by metal fracture; 1/68 (1.5%) in the Gamma 3 U-Blade lag screw group (P = 0.301). In each group, the sliding distance of the lag screw showed a significant difference (P = 0.017), whereas significant sliding over 10 mm showed no statistically significant results. Conclusion: There was only one (1.5%) case of fixation failure in the Gamma 3 U-Blade lag screw group. The sliding distance of the U-Blade was found to be in the middle, between the PFNA II (shorter) and ITST (longer) implants. The new rotational control lag screw seems to be comparable to other screw types. [ABSTRACT FROM AUTHOR]

This paper presents DXR, a toolkit for building immersive data visualizations based on the Unity development platform. Over the past years, immersive data visualizations in augmented and virtual reality (AR, VR) have been emerging as a promising medium for data sense-making beyond the desktop. However, creating immersive visualizations remains challenging, and often require complex low-level programming and tedious manual encoding of data attributes to geometric and visual properties. These can hinder the iterative idea-to-prototype process, especially for developers without experience in 3D graphics, AR, and VR programming. With DXR, developers can efficiently specify visualization designs using a concise declarative visualization grammar inspired by Vega-Lite. DXR further provides a GUI for easy and quick edits and previews of visualization designs in-situ, i.e., while immersed in the virtual world. DXR also provides reusable templates and customizable graphical marks, enabling unique and engaging visualizations. We demonstrate the flexibility of DXR through several examples spanning a wide range of applications. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel machine learning-based voxel classification method for highly-accurate volume rendering. Unlike conventional voxel classification methods that incorporate intensity-based features, the proposed method employs dictionary based features learned directly from the input data using hierarchical multi-scale 3D convolutional sparse coding, a novel extension of the state-of-the-art learning-based sparse feature representation method. The proposed approach automatically generates high-dimensional feature vectors in up to 75 dimensions, which are then fed into an intelligent system built on a random forest classifier for accurately classifying voxels from only a handful of selection scribbles made directly on the input data by the user. We apply the probabilistic transfer function to further customize and refine the rendered result. The proposed method is more intuitive to use and more robust to noise in comparison with conventional intensity-based classification methods. We evaluate the proposed method using several synthetic and real-world volume datasets, and demonstrate the methods usability through a user study. [ABSTRACT FROM PUBLISHER]

CO2 reduction, electrocatalysis, Li-CO2 battery, single-atom catalysts Single-Atom Cadmium-N4 Sites for Rechargeable Li-CO2 Batteries with High Capacity and Ultra-Long Lifetime (Adv. Funct. Keywords: CO2 reduction; electrocatalysis; Li-CO2 battery; single-atom catalysts EN CO2 reduction electrocatalysis Li-CO2 battery single-atom catalysts 1 1 1 06/22/23 20230619 NES 230619 B Single-Atom Catalysts b In article number 2213841, Zhenyu Sun, Yousung Jung, Xinyi Tan, and co-workers report, that single-atom cadmium with a Cd-N SB 4 sb coordination structure enables rapid kinetics of both the discharge and recharge process when employed as a cathode catalyst, and thus facilitates exceptional rate performance in a Li-CO SB 2 sb battery, even up to 10 A g SP -1 sp , and remains stable at a high current density (100 A g SP -1 sp ). [Extracted from the article]

Background: Geospatial information has drawn substantial attention as a means for building a common measurement and monitoring framework that can be employed across different countries all over the world for the sustainable development goals (SDGs) of the United Nations (UN). Determining the appropriate spatial units for measurements is a critical issue, particularly for the goals associated with the safety, resilience, and sustainability of cities and human settlements. Open geospatial technologies are expected to help address this issue of spatial measurement since they comply with geospatial standards and can be easily adopted by both developed and developing countries. Methods: This study evaluates the applicability of open geospatial technologies for the development of a common measurement framework for UN SDG 11. To this end, the study analyzes to what extent national urban information systems of Korea can support the measurement of the target goals and makes recommendations for how open geospatial data and technologies could fill the void that current systems cannot fill at present. Results and discussion: The results of this study show that Korea's urban information systems have an architecture built upon a standard-based open platform and thus can be easily extended by other open geospatial technologies for new developments. Conclusions: From the Korean case study findings, we concluded that open geospatial technologies could serve as an enabler for constructing a worldwide common framework for the measurement of sustainable development goals. [ABSTRACT FROM AUTHOR]

To inhibit Li-dendrite growth on lithium (Li)-metal electrodes, which causes capacity deterioration and safety issues in Li-ion batteries, we prepared a porous polyimide (PI) sponge using a solution-processable high internal-phase emulsion technique with a water-soluble PI precursor solution; the process is not only simple but also environmentally friendly. The prepared PI sponge was processed into porous PI separators and used for Li-metal electrodes. The physical properties (e.g., thermal stability, liquid electrolyte uptake, and ionic conductivity) of the porous PI separators and their effect on the Li-metal anodes (e.g., self-discharge and open-circuit voltage properties after storage, cycle performance, rate capability, and morphological changes) were investigated. Owing to the thermally stable properties of the PI polymer, the porous PI separators demonstrated no dimensional changes up to 180 °C. In comparison with commercialized polyethylene (PE) separators, the porous PI separators exhibited improved wetting ability for liquid electrolytes; thus, the latter improved not only the physical properties (e.g., improved the electrolyte uptake and ionic conductivity) but also the electrochemical properties of Li-metal electrodes (e.g., maintained stable self-discharge capacity and open-circuit voltage features after storage and improved the cycle performance and rate capability) in comparison with PE separators. [ABSTRACT FROM AUTHOR]