26 research outputs found

    INVESTIGATION ON THE CURRENT SITUATION AND COUNTERMEASURES OF EXTRACURRICULAR READING FOR PRIMARY SCHOOL STUDENTS: A CASE STUDY OF ZHEJIANG, CHINA

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    Based on a survey of 697 students in primary schools of Hangzhou, Ningbo, and Jiaxing in Zhejiang Province, this paper found that: (1) 25% of parents support their children to read reference books and regular parent-child reading, but most of the parents are afraid it may negatively influence school curriculum so they limit or against extracurricular reading and do not carry out the parent-child reading; only 27% of teachers often assign extracurricular reading tasks, most rarely or never, parents and schools currently pay little attention to extracurricular reading. (2) Eighty one percent of children spent 2 hours or more on homework or reviewing lessons every day, 88% of them watched about 1 hour of TV every day, and 68% of them played video games for about 1 hour. Except eating, sleeping and commuting, they have an average of 4-5 hours of free time outside school, so more than 50% of primary school students spend less than 0.5 hour reading Chinese books every day. (3) Nearly 80% of children read 2-5 Chinese books every month and spend around ¥500 on books every year; in addition, more than 60% of the respondents read paper books, and the reading of extracurricular English books is close to zero, which caused their limited reading volume, narrow scope of knowledge, restricted international vision, and inadequate reading habits. The situation extracurricular reading is not ideal, which may seriously affect the future academic and career development. To improve the unfavorable situation, this paper put forward the following suggestions: (1) all levels of government should allocate fund to establish and improve bookshelves in school classroom and community library, promote "home - school - community cooperation reading plan", let the children at school can have more 0.5-1 hours of reading at noon, and can approach in the community library for reading on weekend and holidays; (2) distribute free books to low-income families and advocate encouraging parents to spend half an hour reading with their children; (3) the school attaches great importance to the extracurricular reading education, organize pupils in class after school every afternoon 1 hour or so of intensive reading, storytelling and drama class PK activities such as English, both can effectively improve the student's reading interest, also solved the question which is many parents unable to pick up their kids during work at 3:30 p.m.; (4) promote digital reading, reduce the cost of reading, and correctly understand the impact of digital reading on eyesight.  Article visualizations

    On Radio Frequency Fingerprint Identification for DSSS Systems in Low SNR Scenarios

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    Human Hemoglobin Subunit Beta Functions as a Pleiotropic Regulator of RIG-I/MDA5-Mediated Antiviral Innate Immune Responses

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    Hemoglobin is an important oxygen-carrying protein and plays crucial roles in establishing host resistance against pathogens and in regulating innate immune responses. The hemoglobin subunit beta (HB) is an essential component of hemoglobin, and we have previously demonstrated that the antiviral role of the porcine HB (pHB) is mediated by promoting type I interferon pathways. Thus, considering the high homology between human HB (hHB) and pHB, we hypothesized that hHB also plays an important role in the antiviral innate immunity. In this study, we characterized hHB as a regulatory factor for the replication of RNA viruses by differentially regulating the RIG-I- and MDA5-mediated antiviral signaling pathways. Furthermore, we showed that hHB directly inhibited MDA5-mediated signaling by reducing the MDA5-double-stranded RNA (dsRNA) interaction. Additionally, hHB required hHB-induced reactive oxygen species (ROS) to promote RIG-I-mediated signaling through enhancement of K63-linked RIG-I ubiquitination. Taken together, our findings suggest that hHB is a pleiotropic regulator of RIG-I/MDA5-mediated antiviral responses and further highlight the importance of the intercellular microenvironment, including the redox state, in regulating antiviral innate immune responses. IMPORTANCE Hemoglobin, the most important oxygen-carrying protein, is involved in the regulation of innate immune responses. We have previously reported that the porcine hemoglobin subunit beta (HB) exerts antiviral activity through regulation of type I interferon production. However, the antiviral activities and the underlying mechanisms of HBs originating from other animals have been poorly understood. Here, we identified human HB (hHB) as a pleiotropic regulator of the replication of RNA viruses through regulation of RIG-I/MDA5-mediated signaling pathways. hHB enhances RIG-I-mediated antiviral responses by promoting RIG-I ubiquitination depending on the hHB-induced reactive oxygen species (ROS), while it blocks MDA5-mediated antiviral signaling by suppressing the MDA5-dsRNA interaction. Our results contribute to an understanding of the crucial roles of hHB in the regulation of the RIG-I/MDA5-mediated signaling pathways. We also provide novel insight into the correlation of the intercellular redox state with the regulation of antiviral innate immunity

    A Noise-Robust Radio Frequency Fingerprint Identification Scheme for Internet of Things Devices

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    Radio frequency fingerprint (RFF) identification is a potentially effective technique to address the authentication security of Internet of Things (IoT) devices. Since the complex working environment and limited resources of IoT devices, noise is non-negligible in RFF identification of IoT devices. It is a challenge to suppress the noise without damaging the RFF information. In this paper, we propose a robust RFF identification scheme, which consists of a frequency point selection (FPS) based denoising algorithm, and a convolutional neural network (CNN) classifier. The FPS algorithm performs denoising by filtering out all the frequency components that are independent of the RFF. The CNN is designed with a dynamically decreasing learning rate to accelerate learning and obtain optimal identification performance. Experiments were conducted with 54 ZigBee devices to evaluate the performance of the proposed scheme under three different RFF identification scenarios. The results show that the FPS algorithm brings the highest accuracy improvement of about 25% when the training signal-to-noise ratio (SNR) is hybrid and the test SNR is 0 dB

    Influence of Nitrogen Partial Pressure and Substrate Bias on the Mechanical Properties of VN Coatings

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    AbstractVanadium nitride coatings were deposited via magnetron reactive sputtering system with varying nitrogen partial pressures and negative substrate bias to further understand the influence of the sputtering conditions on the microstructure and the mechanical performance. Grazing incidence X-ray diffraction, field emission scanning electron microscopy equipped with energy dispersive X-ray and X-ray photoelectron spectroscopy were used to characterize the microstructure; nano-hardness tester and profilometer were used to measure the mechanical performance. By varying the nitrogen partial pressures from 0.007Pa to 0.29Pa, more compact coating with higher hardness (22.9GPa) was achieved at 0.29Pa. In parallel, the influence of bias voltage on the residual stress and hardness was significant

    Design of A Channel Robust Radio Frequency Fingerprint Identification Scheme

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    Radio frequency fingerprint (RFF) identification is an emerging device authentication technique that exploits the hardware imperfections resulting from the manufacturing process. Due to the varying impact of the wireless channel during RFF training and test stages, it is challenging to design channel independent RFF techniques. This paper designs a channel robust RFF identification scheme by leveraging the different spectrum of adjacent signal symbols, named the difference of the logarithm of the spectrum (DoLoS), which does not rely on a single RFF feature or requires additional manipulation of the devices under test. Specifically, DoLoS exploits the fact that two different symbols in a packet exhibit different RFF features but have a similar channel response during the channel coherence time. We implemented the DoLoS with the IEEE 802.11 orthogonal frequency division multiplexing (OFDM) system as a case study. We carried out extensive experiments using 7 Wi-Fi devices of the same model in different wireless channel environments, including 12 data collection positions in two completely different environments. Compared with conventional RFF identification schemes that do not eliminate channel effects, our scheme is robust to channel variations and the highest identification accuracy is 99.02% in the single-environment evaluation and 97.05% in the cross-environment evaluation

    RING-Domain E3 Ligase-Mediated Host–Virus Interactions:Orchestrating Immune Responses by the Host and Antagonizing Immune Defense by Viruses

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    The RING-domain E3 ligases (RING E3s), a group of E3 ligases containing one or two RING finger domains, are involved in various cellular processes such as cell proliferation, immune regulation, apoptosis, among others. In the host, a substantial number of the RING E3s have been implicated to inhibit viral replication through regulating immune responses, including activation and inhibition of retinoic acid-inducible gene I-like receptors, toll-like receptors, and DNA receptor signaling pathways, modulation of cell-surface expression of major histocompatibility complex, and co-stimulatory molecules. During the course of evolution and adaptation, viruses encode RING E3s to antagonize host immune defense, such as the infected cell protein 0 of herpes simplex virus type 1, the non-structural protein 1 of rotavirus, and the K3 and K5 of Kaposi’s sarcoma-associated herpesvirus. In addition, recent studies suggest that viruses can hijack the host RING E3s to facilitate viral replication. Based on emerging and interesting discoveries, the RING E3s present novel links among the host and viruses. Herein, we focus on the latest research progresses in the RING E3s-mediated host–virus interactions and discuss the outlooks of the RING E3s for future research

    RelativeRFF: Multi-Antenna Device Identification in Multipath Propagation Scenarios

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    Radio frequency fingerprinting (RFF) is a promising solution for realizing secure and efficient device authentication. The multipath channel overshadows and disrupts the RFF extraction, which causes difficulties in training new models in the presence of fading. Existing approaches attempt to deal with this challenge by traversing channels through simulated channel models. However, this solution requires a large amount of data for training and it is difficult to guarantee that the training covers all possible channels. To mitigate the multipath channel effect on RFF with less training data, we propose a new method in a multi-antenna system, named Relative-RFF (R-RFF), which utilizes channel state information (CSI) feedback to counteract the multipath channel. The RFF imperfection relation between the different antenna chains of the device is proved to be retained after the counteraction of the multipath channel. Numerical results demonstrate that the proposed R-RFF can achieve an identification accuracy of 95.9% for 30 UEs in Tapped Delay Line channel with a signal-to-noise ratio of 20 dB
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