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In this paper, a frequency selective surface (FSS) for n41, n78, n257, n258, n260, and n261 bands electromagnetic interference (EMI) shielding is proposed using a deep learning method. The size of the FSS unit cell is 4.8 mm (0.071 λ 0 ), where λ 0 is the wavelength corresponding to the cutoff frequency of the −10 dB stopband where the n41 and n78 bands are located. This FSS exhibits three key characteristics. Firstly, it possesses ultrawideband capability, with a stopband frequency range of 23.922–40.023 GHz and a relative bandwidth reaching 50.4%. Secondly, it effectively shields against electromagnetic radiation in multiple 5 G bands, including n41, n78, n257, n258, n260, and n261. Thirdly, it demonstrates high selectivity, with a very narrow transition band of only 0.405 GHz between the passband and the stopband. To validate the designed FSS, a prototype of this structure was first fabricated for experimentation. The experimental results show that the measured S21 is highly consistent with the simulated S21. Secondly, the unit cell array of FSS is placed above the monopole antenna for co-simulation. It can be observed that after placing the FSS, the intensity of electromagnetic radiation propagating in space is significantly reduced by up to more than 90%. Therefore, the proposed FSS can be effectively applied for EMI shielding in 5 G bands. [ABSTRACT FROM AUTHOR]

The microseism signals before and after rock burst on 1300 working face of a coal mine were collected, and sequential characteristics were analyzed. The db5 is used as wavelet basis function to decompose microseism signals into five layers, and the spectral characteristics and energy percentage of each sub-frequency band are obtained. The analysis results show that before rock burst, the number and energy of microseism increase first and then decrease and then increase; precursor signal appeared one hour before rock burst occurred, the energy is mainly distributed in the middle and high frequency region of 62.5-250 Hz, and the energy percentage reaches 55%; when the rock burst occurs, the amplitude increases significantly, with obvious vibration fluctuations, low frequency signals are the main component, and the energy is mainly concentrated in the low frequency range of 0-62.5 Hz, and accounts for about 70% of the total energy. Precursory of rock burst is obtained: the amplitude increases, the frequency of the microseism is significantly reduced, the frequency band develops from high frequency to low frequency, and low frequency signal increases as the time of foreshock occurs closer to the main shock, the percentage of energy occupied by the low frequency signal also increases. Therefore, sharp reduction of main frequency of the microseismic, obvious increase of amplitude and increase of energy percentage of low-frequency signals can be used as the main feature of precursory of rock burst, combined with daily microseismic times and energy trends, rock burst can be predicted.

My article examines the structure of the nineteenth-century British paper peepshow and the experience of using it. Inspired by the agenda of media archaeology, I argue that an analysis of this medium that goes beyond excavating details of an obscured optical recreation can bring new insight into our understanding of peep media and nineteenth-century visual culture. By discussing the origin and circulation of the paper peepshow and detailing the clear distinction between it and media like the peepshow box and pop-up books, I detach the paper peepshow from the genealogy of these media while stressing the significance of its intermedial relationship with other nineteenth-century visual entertainments. I then adopt the notion of embodied knowledge to explore users' engagement with this medium, drawing from personal handling experience in archives as well as theoretical conceptualisations. My article argues that peering into the paper peepshow should be understood as an act of creativity and imagination, and that the tactile played a crucial role in users' interaction with this medium. This study thus fits well in debates about the embodied or multi-sensory vision in the nineteenth-century context, and functions as another example that affirms the active agency of users of visual recreations of this period. Overall, by analysing significant features of the paper peepshow and the experience of peeping into it, my research also constitutes a small but important expansion in the current understanding of peep media. [ABSTRACT FROM AUTHOR]

In a pressurized water reactor nuclear power plant, metal foreign matter in the rod–rod gap of the fuel assembly is constantly rubbed and collided with the fuel rod under continuous scouring of the coolant, resulting in wear to the fuel rod and even leakage of the perforation. In this work, the effects of different debris shapes and materials on the impact wear behavior of Zr−4 alloy tubes were studied through the dynamic response and damage of Zr−4 alloy tubes under cyclic impact. The results show that the sharper the shape of the impact block, the higher the wear rate of the Zr−4 alloy tube. Although the energy absorption rate of SA 508−A during the impact process is high, most of the energy is used for the wear of the impact block itself and the formation and peeling of the wear debris accumulation layer, and the damage to the Zr−4 alloy tube is small. The wear debris generated by the Zr−4 impact block is not easy to oxidize, and the wear caused by the cyclic impact is more serious. After the Zr−4 impact block cyclically impacts the Zr−4 alloy tube 200 w times, the Zr−4 alloy tube will be perforated due to wear. The oxidation and accumulation of wear debris and the wear mechanism in the impact process are mainly abrasive wear and surface peeling behavior. The occurrence of cutting and wear removal will promote the wear and thinning of the tube wall of the Zr−4 alloy tube, and the tube wall is easily perforated after thinning. [ABSTRACT FROM AUTHOR]

Glioma is the most prevalent and lethal primary brain tumour. Abundant long non‐coding RNAs (lncRNAs) are aberrant and play crucial roles in the oncogenesis of glioma. The exact functions of linc00475 in glioma remain blurred. Here, we analysed the expression levels of linc00475 by qRT‐PCR and discovered that linc00475 was up‐regulated in glioma and predicted a poor prognosis in patients with glioma. Besides, inhibiting linc00475 restrained the progression of glioma in vitro and in vivo. Further experiments confirmed that linc00475 regulated the progression of glioma by acting as a sponge for miR‐141‐3p. Moreover, we detected the binding sites of linc00475 and miR‐141‐3p, the YAP1‐ 3′UTR and miR‐141‐3p by luciferase reporters. The rescue assays confirmed that inhibiting linc00475 restrained the progression of glioma through the miR‐141‐3p/YAP1 pathway. Collectively, our research demonstrates the key roles of linc00475 in glioma, which could be a promising therapeutic target. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the consistency between the clinical diagnostic criteria and the ascertained diagnostic criteria for diabetic peripheral neuropathy (DPN) in the Preventive and Treatment Guidelines of Diabetes in China (2013) and explore an economic, convenient, and accurate approach to DPN diagnosis., Methods: The patients with type 2 diabetes admitted in our department from April to June, 2014 were examined for nerve conduction velocity, 10 g nylon silk, vibration threshold value, sense of temperature and pain, and ankle reflex. The sensitivity, specificity, positive predictive value, negative predictive value, Youden index, and Kappa value were calculated to assess the diagnostic power of the two diagnostic criteria., Results: Of the 151 patients enrolled, 106 (70.2%) had a diagnosis of DPN consistent with the ascertained diagnostic criteria, as compared to 86 (56.95%) who were diagnosed according to the clinical diagnostic criteria; the latter patients accounted for 81.13% of former cases. The sensitivity, specificity, positive predictive value, negative predictive value, Youden index, and Kappa value of the clinical diagnostic criteria were 80.19%, 97.78%, 98.84%, 67.69%, 77.97%, and 0.69, respectively, which were highly consistent with those of the ascertained diagnostic criteria; the sensitivity to compression showed a poor consistency between the two diagnostic criteria. In the 5 screening tests, the combined test of temperature sensation, vibration perception, and ankle reflex showed the highest AUC value among their different combinations., Conclusion: The clinical diagnostic criteria for DPN show good consistency with the ascertained diagnostic criteria, and for patients with clinical symptoms or with only one positive sign, combination of the two diagnostic criteria can achieve the maximum diagnostic power.