Memory Performance Characterization of SPEC CPU2006 Benchmarks Using TSIM

AbstractThis paper uses TSIM, a cycle accurate architecture simulator, to characterize the memory performance of SPEC CPU2006 Benchmarks under CMP platform. The experiment covers 54 workloads with different input sets, and collects statistical information of instruction mixture and cache behaviors. By detecting the cyclical changes of MPKI, this paper clearly shows the memory performance phases of some SPEC CPU2006 programs. These performance data and analysis results can not only help program developers and architects understand the memory performance caused by system architecture better, but also guide them in software and system optimization

Development of a novel detection technology for drug resistance mutation sites of Mycobacterium tuberculosis using Luminex liquid chip technology

Purpose: To develop a novel detection technology for drug-resistance mutation sites of Mycobacterium tuberculosis (MTB) using a Luminex liquid chip.Methods: Using polymerase chain reaction (PCR) amplification and hybridization analysis, MTB infection and drug-resistant mutation sites of the first-line and second-line anti-MTB drugs were simultaneously identified. A novel detection method was applied to analyze the wild-type standard strains of MTB and 33 clinical samples, and the results were compared with Sanger sequencing results for PCR products.Results: It was revealed that the sensitivity (100 %) and specificity (100 %) of the novel detection method for 31 samples were satisfactory, and all mutation sites were correctly detected. Compared with traditional PCR and culture-based drug sensitivity test, the novel detection method increased the speed of identification of drug-resistant TB, reduced clinicians' workload, and decreased treatment cost. Among 31 samples, 12.90 % were resistant to isoniazid (4/31), 35.48 % to rifampicin (11/31), and 12.90 % to ofloxacin (p < 0.05). Furthermore, 2 (6.45 %) samples were resistant to both isoniazid and rifampicin, 2 (6.45 %) samples to both rifampicin and ofloxacin, and 1 (3.22 %) sample to both isoniazid and ofloxacin, and 1 (3.22%) sample to all the three drugs (p < 0.05).Conclusion: Development and wide application of this novel detection method will facilitate the treatment of MTB, thus reducing the spread of drug-resistant MTB, and improving the prevention and treatment of MTB

Massively Parallel Sequencing of a Chinese Family with DFNA9 Identified a Novel Missense Mutation in the LCCL Domain of COCH

DFNA9 is a late-onset, progressive, autosomal dominantly inherited sensorineural hearing loss with vestibular dysfunction, which is caused by mutations in the COCH (coagulation factor C homology) gene. In this study, we investigated a Chinese family segregating autosomal dominant nonsyndromic sensorineural hearing loss. We identified a missense mutation c.T275A p.V92D in the LCCL domain of COCH cosegregating with the disease and absent in 100 normal hearing controls. This mutation leads to substitution of the hydrophobic valine to an acidic amino acid aspartic acid. Our data enriched the mutation spectrum of DFNA9 and implied the importance for mutation screening of COCH in age related hearing loss with vestibular dysfunctions

1,4-Bis(imidazol-1-yl)benzene–terephthalic acid (1/1)

In the title compound, C12H10N4·C8H6O4, 1,4-bis­(imidazol-1-yl)benzene and terephthalic acid mol­ecules are joined via strong O—H⋯N hydrogen bonds to form infinite zigzag chains. Both mol­ecules are located on crystallographic inversion centers. The O—H⋯N hydrogen-bonded chains are assembled into two-dimensional layers through weak C—H⋯O and strong π–π stacking inter­actions [centroid–centroid distance = 3.818 (2) Å], leading to the formation of a three-dimensional supra­molecular structure

Skyrmion-Bubble Bundles in an X-type Sr2Co2Fe28O46 Hexaferrite above Room Temperature

Magnetic skyrmions are spin swirls that possess topological nontriviality and are considered particle-like entities. They are distinguished by an integer topological charge Q. The presence of skyrmion bundles provides an opportunity to explore the range of values for Q, which is crucial for the advancement of topological spintronic devices with multi-Q properties. In this study, we present a new material candidate, Sr2Co2Fe28O46 hexaferrite of the X-type, which hosts small dipolar skyrmions at room temperature and above. By exploiting reversed magnetic fields from metastable skyrmion bubbles at zero fields, we can incorporate skyrmion-bubble bundles with different interior skyrmion/bubble numbers, topological charges, and morphologies at room temperature. Our experimental findings are consistently supported by micromagnetic simulations. Our results highlight the versatility of topological spin textures in centrosymmetric uniaxial magnets, thereby paving the way for the development of room-temperature topological spintronic devices with multi-Q characteristics.Comment: https://doi.org/10.1002/adma.20230611

Deterministic generation of skyrmions and antiskyrmions by electric current

Magnetic skyrmions are nanoscale spin whirlpools that promise breakthroughs in future spintronic applications. Controlled generation of magnetic skyrmions by electric current is crucial for this purpose. While previous studies have demonstrated this operation, the topological charge of the generated skyrmions is determined by the direction of the external magnetic fields, thus is fixed. Here, we report the current-induced skyrmions creation in a chiral magnet FeGe nanostructure by using the \emph{in-situ} Lorentz transmission electron microscopy. We show that magnetic skyrmions or antiskyrmions can be both transferred from the magnetic helical ground state simply by controlling the direction of the current flow at zero magnetic field. The force analysis and symmetry consideration, backed up by micromagnetic simulations, well explain the experimental results, where magnetic skyrmions or antiskyrmions are created due to the edge instability of the helical state in the presence of spin transfer torque. The on-demand generation of skyrmions and control of their topology by electric current without the need of magnetic field will enable novel purely electric-controlled skyrmion devices.Comment: 5 pages and 4 figure

Observation of Hybrid Magnetic Skyrmion Bubbles in Fe3Sn2 Nanodisks

It is well known that there are two types of magnetic bubbles in uniaxial magnets. Here, using Lorentz-transimission electronic microscopy magnetic imaging, we report the direct experimental observation of 3D type-III hybrid bubbles, which comprise N\'eel-twisted skyrmion bubbles with topological charge Q = -1 in near-surface layers and type-II bubbles with Q = 0 in interior layers, in Fe3Sn2 nanodisks. Using the tilted magnetic field, we further show the controlled topological magnetic transformations of three types of bubbles in a confined ferromagnetic nanodisk. Our observations are well reproduced using micromagnetic simulations based on measured magnetic parameters. Our results advance fundamental classification and understanding of magnetic bubbles, which could propel the applications of three-dimensional magnetism.Comment: https://doi.org/10.1103/PhysRevB.107.17442

Current-Controlled Skyrmion Number in Confined Ferromagnetic Nanostripes

Skyrmions are vortex-like localized magnetic structures that possess an integer-valued topological index known as the skyrmion number or topological charge. Skyrmion number determines the topology-related emergent magnetism, which is highly desirable for advanced storage and computing devices. In order to achieve device functions, it is necessary to manipulate the skyrmion number in confined nanostructured geometries using electrical methods. Here, we report the reliable current-controlled operations for manipulating the skyrmion number through reversible topological transformations between skyrmion chains and stripe domains in confined Fe3Sn2 nanostripes. The results of micromagnetic simulations are successful in numerically reproducing our experiments and explaining them through the combined effect of current-induced Joule heating and magnetic hysteresis. These findings hold the potential to advance the development of topological spintronic devices.Comment: https://doi.org/10.1002/adfm.20230404