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We are examining a second-order system of non-stiff Initial Value Problems (IVP), focusing on a scenario where the first derivatives are not present. In the realm of solving IVPs, Runge-Kutta-Nystrom (RKN) pair s have proven to be highly effective. In order to achieve a pair with eighth and sixth order accuracy, we need to find a solution to a well-defined set of equations regarding the coefficients. Traditionally, pairs are constructed to go through eight stages per step. However, we propose a novel approach with nine stages per step, which enables the creation of pairs with orders 8 and 6 that have notably smaller truncation errors. Our paper introduces a new pair that, as expected, outperforms existing pairs of the same orders in a range of important problems. [ABSTRACT FROM AUTHOR]

Due to the fine-grained communication scenarios characterization and stability, Wi-Fi channel state information (CSI) has been increasingly applied to indoor sensing tasks recently. Although spatial variations are explicitly reflected in CSI measurements, the representation differences caused by small contextual changes are easily submerged in the fluctuations of multipath effects, especially in device-free Wi-Fi sensing. Most existing data solutions cannot fully exploit the temporal, spatial, and frequency information carried by CSI, which results in insufficient sensing resolution for indoor scenario changes. As a result, the well-liked machine learning (ML)- based CSI sensing models still struggling with stable performance. This paper formulates a time-frequency matrix on the premise of demonstrating that the CSI has low-rank potential and then proposes a distributed factorization algorithm to effectively separate the stable structured information and context fluctuations in the CSI matrix. Finally, a multidimensional tensor is generated by combining the time-frequency gradients of CSI, which contains rich and fine-grained real-time contextual information. Extensive evaluations and case studies highlight the superiority of the proposal. [ABSTRACT FROM AUTHOR]

Polymers are advantageous in increasing hydrogen storage density of tanks due to their lightweight. Moreover, a uniform aggregate structure can enhance their advantages. However, achieving such as structure solely through screw extrusion can be challenging in liner moldings. This study reported a micronano torsional laminated extrusion equipment that can be used before the die to effectively improve the composite orientation and reduce intercrystalline defects through divides, laminated thinning, and biaxial stretching of the melt with a strong drag flow field. The resulting HDPE/PA6 achieved a reduced helium permeation coefficient by up to 20.1% with a more pronounced effect on the diffusion than that on the dissolution. The mechanical property tests demonstrated an improvement in strength by up to 24.5% and modulus by up to 49.1% with the expanded range of toughness fracture. However, PA6 and HDPE exhibited limitations in terms of the moldable size and storage ability owing to their melt strength and gas barrier properties, respectively. Based on the analysis of the melt strength thresholds of HDPE/PA6, the PA6 content in the composites should be <70 wt% for blow molding and <50 wt% for welding. This study provides a novel approach for forming large-diameter and thin-walled liner billets through extrusion and welding. [ABSTRACT FROM AUTHOR]

The need for effective and adaptive technologies for carbon dioxide (CO2) mitigation targeting global net-zero carbon emissions is critically growing. Hence, innovative technologies for CO2 reduction have attracted worldwide interest from scientific research communities. The use of liquid metals for the conversion of CO2 into carbon or solid carbonaceous products has gained increasing attention in recent years due to their high activity and resistance to coking. Here, a facile approach for the reduction of CO2 to solid carbon using liquid Mg at and near room temperature, and atmospheric pressure is presented. In this process, magnesium (Mg) plays a major role in driving the dissociation of CO2 to its elemental constituents, carbon and oxygen. During the reaction process, Mg ions dissolve in gallium (Ga) liquid metal alloy, diffuse to the gas-liquid interface, and reduce CO2 to carbon while undergoing an oxidation reaction. The electrochemical method ensures a sustainable cyclic process by reducing Mg and Ga ions back to their metallic counterpart. The use of liquid metal alloys for CO2 reduction reactions can enable to achieve CO2 capture and storage at room temperature, setting a new foundation for the future exploration of efficient CO2 mitigation issues. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study on the cold-chain related transmission of SARS-COV-2. Topics mentioned include the use of pandemic-scale phylogenomics, the reduction of lineage-specific in the SARS-COV-2 evolutionary rate, the effect of two mutation-dormant variants, and the association of the COVID-19 outbreak with spillover accidents from cold-chains.

Age-related cataract (ARC) is one of the leading blinding eye diseases worldwide. Chronic oxidative stress and the apoptosis of human lens epithelial cells (HLECs) have been suggested to be themechanism underlying cataract formation. Acetyl-11-keto-ß-boswellic acid (AKBA) is a pentacyclic triterpene with antioxidative and antiapoptotic effects. In this study, we investigated the potential effects of AKBA on oxidative-induced HLECs injury and cataract formation. H2O2 was used to simulate HLECs oxidative injury in vitro, andNa2SeO3 was applied to establish an in vivo cataract model. In our current study, a cell counting kit-8 (CCK-8) assay was performed to evaluate the effects of H2O2 and AKBA on cell viability in vitro. Intracellular reactive oxygen species (ROS) levels were measured with the ROS assay to verify the antioxidant capacity of AKBA. Apoptotic cells were detected and measured by TUNEL staining and flow cytometry, and quantitative real-time (qRT)-PCR and Western blotting were applied to examine the transcription and expression of apoptosis-related proteins. Furthermore, immunofluorescence staining was performed to locate factor-erythroid 2-related factor 2 (Nrf2), and the protein levels of Nrf2, kelch-like ECH-associated protein 1 (Keap1) and heme oxygenase-1 (HO-1) were determined by Western blotting. Finally, we observed the degree of lens opacity and performed hematoxylin-eosin (H&E) staining to assess the protective effect of AKBA on cataract formation in vivo. AKBA increased HLECs viability under H2O2 stimulation, decreased intracellular ROS levels and alleviated the cell apoptosis rate in vitro. AKBA significantly decreased the expression of caspase-3 and Bax and increased the content of Bcl-2. The results of immunofluorescence and immunohistochemical staining proved that the expression and nuclear translocation of Nrf2 were activated with AKBA treatment in vivo and in vitro. Moreover, computational docking results showed that AKBA could bind specifically to the predicted Keap1/Nrf2 binding sites. After AKBA activation, Nrf2 dissociates from the Nrf2/Keap1 complex, translocates into the nucleus, and subsequently promotes HO-1 expression. In addition, AKBA attenuated lens opacity in selenite-induced cataracts. Overall, these findings indicated that AKBA alleviated oxidative injury and cataract formation by activating the Keap1/Nrf2/HO-1 cascade. Therefore, our current study highlights that AKBA may serve as a promising treatment for ARC progression. [ABSTRACT FROM AUTHOR]

Racial disparities in breast cancer mortality persist, and young Black women have higher disease incidence compared with White women. We compared trends in breast cancer mortality for young Black and White women with mortality trends for other common diseases from 1979 to 2010. In contrast to other cancers, ischemic heart disease, and stroke, the breast cancer mortality disparity has widened over the past 30 years, suggesting that unique aspects of disease biology, prevention, and treatment may explain persistent racial differences for young women. [ABSTRACT FROM AUTHOR]

Recently, phase cancellation metasurface has caused much attention due to its great capability of realizing radar cross section (RCS) reduction. However, owing to the intrinsic resonance property of the meta-atom, it is still challenging to expand the RCS reduction bandwidth. Here, we present a novel strategy to design ultra-broadband low-scattering metasurface by using the mixed meta-atoms combined with the evolutionary algorithm. The mixed meta-atoms are composed of single-layer or double-layer reflected elements, and the six different unit configurations are adopted to generate various reflection phases over a wide band. The planar array theory combined with particle swarm optimization (PSO) algorithm is employed to obtain the optimal mixed meta-atoms and their arrangement. The proposed low-scattering metasurface can achieve more than 10 dB RCS reduction between 5 and 18 GHz with a fractional bandwidth of 113% under normal incidence for both polarizations. The experimental results agree well with the simulated ones, and its bandwidth of the 10 dB RCS reduction reaches about 105.3%. In addition, our metasurface is still demonstrated to have the wide-angle stability for low-scattering property. The proposed design provides a feasible way to achieve ultra-broadband RCS reduction, which may find potential applications in electromagnetic fields. [ABSTRACT FROM AUTHOR]