35 research outputs found

    Technology of high-speed storage for target signal based on ARM7 + double NAND memory

    Get PDF
    Based on analysis of principle of interval velocity measurement system and characteristics of target signal, this paper proposed a thought to research accurate extraction of target signal by obtaining the completed target signal. A real-time high-speed storage method based on ARM7 and double NAND memory is proposed in this paper, and is used to deposit the completed target signal. This method lays foundations for achieving high-speed continuous firing velocity measurement, as well as the study on accurate extraction technology of the target signal. The technology has been successfully applied to a muzzle velocity calibration system, and the completed target signals and data of continuous firing velocity measurement have been obtained, which shows the performance is reliable and steady

    Protein resonance assignment by BSH‐CP‐based 3D solid‐state NMR experiments: A practical guide

    Get PDF
    Solid-state NMR (ssNMR) spectroscopy has evolved into a powerful method to obtain structural information and to study the dynamics of proteins at atomic resolution and under physiological conditions. The method is especially well suited to investigate insoluble and noncrystalline proteins that cannot be investigated easily by X-ray crystallography or solution NMR. To allow for detailed analysis of ssNMR data, the assignment of resonances to the protein atoms is essential. For this purpose, a set of three-dimensional (3D) spectra needs to be acquired. Band-selective homo-nuclear cross-polarization (BSH-CP) is an effective method for magnetization transfer between carbonyl carbon (CO) and alpha carbon (CA) atoms, which is an important transfer step in multidimensional ssNMR experiments. This tutorial describes the detailed procedure for the chemical shift assignment of the backbone atoms of 13C–15N-labeled proteins by BSH-CP-based 13C-detected ssNMR experiments. A set of six 3D experiments is used for unambiguous assignment of the protein backbone as well as certain side-chain resonances. The tutorial especially addresses scientists with little experience in the field of ssNMR and provides all the necessary information for protein assignment in an efficient, time-saving approach.European Research Council http://dx.doi.org/10.13039/501100000781Max Planck Society http://dx.doi.org/10.13039/501100004189Leibniz‐Forschungsinstitut fĂŒr Molekulare PharmakologiePeer Reviewe

    Absence of nematic instability in the kagome metal CsV3_3Sb5_5

    Full text link
    Ever since the discovery of the charge density wave (CDW) transition in the kagome metal CsV3_3Sb5_5, the nature of its symmetry breaking is under intense debate. While evidence suggests that the rotational symmetry is already broken at the CDW transition temperature (TCDWT_{\rm CDW}), an additional electronic nematic instability well below TCDWT_{\rm CDW} was reported based on the diverging elastoresistivity coefficient in the anisotropic channel (mE2gm_{E_{2g}}). Verifying the existence of a nematic transition below TCDWT_{\rm CDW} is not only critical for establishing the correct description of the CDW order parameter, but also important for understanding the low-temperature superconductivity. Here, we report elastoresistivity measurements of CsV3_3Sb5_5 using three different techniques probing both isotropic and anisotropic symmetry channels. Contrary to previous reports, we find the anisotropic elastoresistivity coefficient mE2gm_{E_{2g}} is temperature-independent except for a step jump at TCDWT_{\rm CDW}. The absence of nematic fluctuations is further substantiated by measurements of the elastocaloric effect, which show no enhancement associated with nematic susceptibility. On the other hand, the symmetric elastoresistivity coefficient mA1gm_{A_{1g}} increases below TCDWT_{\rm CDW}, reaching a peak value of 90 at T∗=20T^* = 20 K. Our results strongly indicate that the phase transition at T∗T^* is not nematic in nature and the previously reported diverging elastoresistivity is due to the contamination from the A1gA_{1g} channel

    Extracellular vesicles as a new frontier of diagnostic biomarkers in osteosarcoma diseases: a bibliometric and visualized study

    Get PDF
    The use of liquid biopsy in cancer research has grown exponentially, offering potential for early detection, treatment stratification, and monitoring residual disease and recurrence. Exosomes, released by cancer cells, contain tumor-derived materials and are stable in biofluids, making them valuable biomarkers for clinical evaluation. Bibliometric research on osteosarcoma (OS) and exosome-derived diagnostic biomarkers is scarce. Therefore, we aimed to conduct a bibliometric evaluation of studies on OS and exosome-derived biomarkers. Using the Web of Science Core Collection database, Microsoft Excel, the R “Bibliometrix” package, CiteSpace, and VOSviewer software, quantitative analyses of the country, author, annual publications, journals, institutions, and keywords of studies on exosome-derived biomarkers for OS from 1995 to 2023 were performed. High-quality records (average citation rate ≄ 10/year) were filtered. The corresponding authors were mainly from China, the USA, Australia, and Canada. The University of Kansas Medical Center, National Cancer Center, Japan, and University of Kansas were major institutions, with limited cooperation reported by the University of Kansas Medical Center. Keyword analysis revealed a shift from cancer progression to mesenchymal stem cells, exosome expression, biogenesis, and prognostic biomarkers. Qualitative analysis highlighted exosome cargo, including miRNAs, circRNAs, lncRNAs, and proteins, as potential diagnostic OS biomarkers. This research emphasizes the rapid enhancement of exosomes as a diagnostic frontier, offering guidance for the clinical application of exosome-based liquid biopsy in OS, contributing to the evolving landscape of cancer diagnosis

    Functional analysis of the GbDWARF14 gene associated with branching development in cotton

    Get PDF
    Plant architecture, including branching pattern, is an important agronomic trait of cotton crops. In recent years, strigolactones (SLs) have been considered important plant hormones that regulate branch development. In some species such as Arabidopsis, DWARF14 is an unconventional receptor that plays an important role in the SL signaling pathway. However, studies on SL receptors in cotton are still lacking. Here, we cloned and analysed the structure of the GbD14 gene in Gossypium barbadense and found that it contains the domains necessary for a SL receptor. The GbD14 gene was expressed primarily in the roots, leaves and vascular bundles, and the GbD14 protein was determined via GFP to localize to the cytoplasm and nucleus. Gene expression analysis revealed that the GbD14 gene not only responded to SL signals but also was differentially expressed between cotton plants whose types of branching differed. In particular, GbD14 was expressed mainly in the axillary buds of normal-branching cotton, while it was expressed the most in the leaves of nulliplex-branch cotton. In cotton, the GbD14 gene can be induced by SL and other plant hormones, such as indoleacetic acid, abscisic acid, and jasmonic acid. Compared with wild-type Arabidopsis, GbD14-overexpressing Arabidopsis responded more rapidly to SL signals. Moreover, we also found that GbD14 can rescue the multi-branched phenotype of Arabidopsis Atd14 mutants. Our results indicate that the function of GbD14 is similar to that of AtD14, and GbD14 may be a receptor for SL in cotton and involved in regulating branch development. This research provides a theoretical basis for a profound understanding of the molecular mechanism of branch development and ideal plant architecture for cotton breeding improvements

    Reversible Non-Volatile Electronic Switching in a Near Room Temperature van der Waals Ferromagnet

    Full text link
    The ability to reversibly toggle between two distinct states in a non-volatile method is important for information storage applications. Such devices have been realized for phase-change materials, which utilizes local heating methods to toggle between a crystalline and an amorphous state with distinct electrical properties. To expand such kind of switching between two topologically distinct phases requires non-volatile switching between two crystalline phases with distinct symmetries. Here we report the observation of reversible and non-volatile switching between two stable and closely-related crystal structures with remarkably distinct electronic structures in the near room temperature van der Waals ferromagnet Fe5−ή_{5-\delta}GeTe2_2. From a combination of characterization techniques we show that the switching is enabled by the ordering and disordering of an Fe site vacancy that results in distinct crystalline symmetries of the two phases that can be controlled by a thermal annealing and quenching method. Furthermore, from symmetry analysis as well as first principle calculations, we provide understanding of the key distinction in the observed electronic structures of the two phases: topological nodal lines compatible with the preserved global inversion symmetry in the site-disordered phase, and flat bands resulting from quantum destructive interference on a bipartite crystaline lattice formed by the presence of the site order as well as the lifting of the topological degeneracy due to the broken inversion symmetry in the site-ordered phase. Our work not only reveals a rich variety of quantum phases emergent in the metallic van der Waals ferromagnets due to the presence of site ordering, but also demonstrates the potential of these highly tunable two-dimensional magnets for memory and spintronics applications

    A repeating fast radio burst associated with a persistent radio source

    Get PDF
    The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium1, which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs2, in at least one case there is evidence for an extreme magneto-ionic local environment3,4 and a compact persistent radio source5. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately 903−111+72 parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies2,6, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications

    Solar Ring Mission: Building a Panorama of the Sun and Inner-heliosphere

    Full text link
    Solar Ring (SOR) is a proposed space science mission to monitor and study the Sun and inner heliosphere from a full 360{\deg} perspective in the ecliptic plane. It will deploy three 120{\deg}-separated spacecraft on the 1-AU orbit. The first spacecraft, S1, locates 30{\deg} upstream of the Earth, the second, S2, 90{\deg} downstream, and the third, S3, completes the configuration. This design with necessary science instruments, e.g., the Doppler-velocity and vector magnetic field imager, wide-angle coronagraph, and in-situ instruments, will allow us to establish many unprecedented capabilities: (1) provide simultaneous Doppler-velocity observations of the whole solar surface to understand the deep interior, (2) provide vector magnetograms of the whole photosphere - the inner boundary of the solar atmosphere and heliosphere, (3) provide the information of the whole lifetime evolution of solar featured structures, and (4) provide the whole view of solar transients and space weather in the inner heliosphere. With these capabilities, Solar Ring mission aims to address outstanding questions about the origin of solar cycle, the origin of solar eruptions and the origin of extreme space weather events. The successful accomplishment of the mission will construct a panorama of the Sun and inner-heliosphere, and therefore advance our understanding of the star and the space environment that holds our life.Comment: 41 pages, 6 figures, 1 table, to be published in Advances in Space Researc
    corecore