Test of T violation in neutral B decays

T violation should be tested independently of CP violation. Besides K system, B meson decays provide another good place to study T violation. In the Standard Model, T violation in $B^0 \rightleftharpoons \bar{B^0}$ oscillation is expected to be small. The angular distribution of $B\to VV$ decay permits one to extract the T-odd correlation. In the absence of final state interaction, T violation in $B\to J/\psi(l^+ l^-) K^*(K_S\pi^0)$ decay can reach $4-7$ via $B^0-\bar{B^0}$ mixing.Comment: Latex, 11 pages, revised version will appear in PL

Curriculum Reform and Practice Exploration of "Foundation of Innovation and Entrepreneurship" for College Normal Majors

According to the statistics of the Ministry of Education, the scale of ordinary college graduates in 2023 is expected to reach 11.58 million, an increase of 820,000 compared with 2022 (General Office of the State Council of China, 2015). This figure once again hit a record high in employment, and the employment situation is becoming more and more severe. All walks of life in society have higher and higher expectations for the comprehensive ability of college students, and college students are facing greater pressure and challenges in the process of job-hunting. This paper will discuss the curriculum design, teaching mode, education and teaching reform strategy, experimental research, conclusions and prospects, so as to provide some useful references for the education and teaching reform of innovation and entrepreneurship management courses for college students, and improve the quality of graduate training and employment competitiveness

On asymptotic stability of discrete-time non-autonomous delayed Hopfield neural networks

AbstractIn this paper, we obtain some sufficient conditions for determining the asymptotic stability of discrete-time non-autonomous delayed Hopfield neural networks by utilizing the Lyapunov functional method. An example is given to show the validity of the results

Molecular characterization of a novel thermostable laccase PPLCC2 from the brown rot fungus Postia placenta MAD-698-R

AbstractBackgroundLaccase has been considered important for the degradation of lignocellulose by wood rot fungi. The properties and functions of laccase in white rot fungi have been investigated extensively, but those from brown rot fungi remain largely unknown. In this paper, a laccase isoform Pplcc2 from the brown rot fungus Postia placenta MAD-698-R was expressed heterologously in Pichia pastoris GS115, purified and the properties of the enzyme were determined.ResultsThe molecular weight of the protein was determined to be 67kDa using SDS-PAGE. It cannot oxidize syringaldazine (SGZ), but it can oxidize 2,2′-azino-di-(3-ethylbenzothialozin-6-Sulfonic acid) (ABTS) and 2,6-dimethoxyphenol (DMP). Specific activity for ABTS was 1960±19Unit/mg. The catalytic constant (kcat) was 1213±18.3s-1 for ABTS and 293.2±21.9s-1 for DMP. Km was 22.08μM for ABTS and 11.62μM for DMP. The optimal pH for the oxidation of ABTS and DMP was 3.5 and 5.0 respectively. The optimal temperature for the oxidation of ABTS and DMP was 60°C.ConclusionsThis is the first identified thermo activated and thermostable laccase in brown rot fungi. This investigation will contribute to understanding the roles played by laccases in brown rot fungi

Impact base excitation method with stacked PZT actuator for MEMS dynamic characterization

An impact base excitation method with stacked PZT actuator for MEMS dynamic characterization was studied. A typical impact base excitation device mainly includes a stacked PZT actuator, a base structure and an impulse power source. The principle of this method is as follows. The tested microstructure was attached on the top surface of PZT through the base structure in between. Applying a transient impulse voltage on PZT, an impact will be generated in the vertical direction of PZT. The impact will strike the base structure to vibrate. The tested microstructure can be excited by the movement of the base structure. Basing on the principle of this method, a dynamic measurement system for piezoresistive microcantilevers was established. A laser deflection system was developed to measure the frequency bandwidth of excitation device. The experiments on the frequency bandwidth of excitation device and the dynamic characteristics of a T-shaped piezoresistive microcantilever were carried out. The results show that this method is effective for MEMS dynamic characteristics measurement

ConvFormer: Closing the Gap Between CNN and Vision Transformers

Vision transformers have shown excellent performance in computer vision tasks. However, the computation cost of their (local) self-attention mechanism is expensive. Comparatively, CNN is more efficient with built-in inductive bias. Recent works show that CNN is promising to compete with vision transformers by learning their architecture design and training protocols. Nevertheless, existing methods either ignore multi-level features or lack dynamic prosperity, leading to sub-optimal performance. In this paper, we propose a novel attention mechanism named MCA, which captures different patterns of input images by multiple kernel sizes and enables input-adaptive weights with a gating mechanism. Based on MCA, we present a neural network named ConvFormer. ConvFormer adopts the general architecture of vision transformers, while replacing the (local) self-attention mechanism with our proposed MCA. Extensive experimental results demonstrated that ConvFormer achieves state-of-the-art performance on ImageNet classification, which outperforms similar-sized vision transformers(ViTs) and convolutional neural networks (CNNs). Moreover, for object detection on COCO and semantic segmentation tasks on ADE20K, ConvFormer also shows excellent performance compared with recently advanced methods. Code and models will be available