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Visible Light Communication (VLC) has become an effective underwater communication technology due to its advantages such as fast transmission speed and strong confidentiality. When light propagates underwater, it is prone to scattering, resulting in a decrease in the energy of light propagation with the increase of transmission distance. Therefore, improving the responsiveness of the receiving end is the key technology to achieve underwater VLC. This article first designs a new holographic waveguide focusing system for the front end of the detector, which can effectively improve the signal-to-noise ratio of underwater detectors. Then, we construct a low-cost antimony sulfide thin film detector with weak light detection capability. Based on the built VLC system, the experimental results show that the dark current of the receiver detector is only 10-7 A/cm2, with a 3 dB bandwidth of 220 kHz, a response of 0.2 A/W, and an external quantum efficiency of over 70% in the blue green light band. Therefore, the new antimony sulfide thin film detector combined with a holographic waveguide focusing system can achieve weak light detection of visible light, making it a very effective underwater visible light receiving system.

Background With the aggravation of aging trend, the influence of intergenerational support on the health of the elderly has gradually attracted attention, and the absence of spiritual care and life care is an important factor for the occurrence of health problems in the elderly, but there is a lack of scientific evaluation tools to evaluate the cognitive level of old-age care. Objective To develop a Knowledge, Attitude and Practice about Filial Piety Ethics Questionnaires for Offspring and Grandchildren in the process of elderly care, and to test its reliability and validity. Methods From April to July 2021, the first draft of the questionnaire was determined by searching relevant contents in databases such as PubMed, Web of Science, China Knowledge Network and Wanfang Data Knowledge Service Platform, and using the theory of knowledge, attitude and practice and Maslow's hierarchy of needs as the theoretical framework, combined with literature review, national maintenance laws, qualitative interviews, the questionnaire was refined with results of the Delphi expert consensus and pre-survey. From October 2021 to March 2022, 270 subjects from each generation were selected for the formal survey and 50 subjects from the offspring and 38 subjects from the grangchildren were selected for test-retest reliability using the random cluster sampling method. A total of 540 questionnaires were distributed, 270 questionnaires for each generation. A total of 528 valid questionnaires were returned, 264 valid questionnaires for each generation, with a valid return rate of 97.8%. Its reliability and validity were analyzed to determine the final questionnaire entry. Results The Knowledge, Attitude and Practice about Filial Piety Ethics Questionnaires for Offsprings included 3 dimensions and 34 items. Exploratory factor analysis produced 3 factors, with a cumulative variance contribution rate of 64.455%. The content validity of each item ranged from 0.867 to 1.000, and the average content validity of the questionnaire was 0.967. Cronbach's α coefficient was 0.953, split-half reliability was 0.811, and test-retest reliability was 0.987. The Knowledge, Attitude and Practice about Filial Piety Ethics Questionnaires for Grandchildren consisted of 31 items in 3 dimensions. Exploratory factor analysis produced three factors, the cumulative variance contribution rate was 64.641%; the content validity of each item ranged from 0.867 to 1.000, the average content validity of the questionnaire was 0.964; Cronbach's α coefficient was 0.952, split-half reliability was 0.837, and test-retest reliability was 0.991. Conclusion The developed questionnaire has good reliability and validity, and can be used as a research tool to evaluate the current status of filial piety ethic knowledge, attitude and behavior of offsprings and grandchildren in the process of elderly care.

Slow-release urea, as an environmentally friendly fertiliser, can provide a continuous and uniform supply of nutrients needed by the crop, reduce the amount and frequency of fertiliser application, and promote the uptake and utilisation of nitrogen in crops. The production of E. ferox is often dominated by the application of quick-acting fertilisers, resulting in serious problems of over-fertilisation, inappropriate periods of fertilisation, eutrophication of soil and water due to fertilisation, and difficulties in applying fertilisers. Therefore, in this study, different amounts (CK, T1, T2, T3, T4, T5) of SRU (Slow-release Urea) were first applied, and T3 (18.8 kg·667 m−2) was found to significantly improve both yield and quality. Further, it was found that under different SRU (CK, S1, S2, S3, S4) application period treatments, application of 18.8 kg·667 m−2 at AFP20 (S2) period significantly increased the yield and quality of E. ferox. In the seed kernels of E. ferox, the total yield, soluble sugar content, total starch, and flavonoid content increased significantly by 10.35%, 36.40%, 5.91%, and 22.80%, respectively, compared with CK. In addition, the expression of key sugar transporter genes (EfSWEETs), flavonoid synthesis-related genes (EfPAL, EfDFR, etc.), and starch synthesis-related enzyme activities (SBE, SSS, GBSS) were significantly increased. By exploring the quantity of application and application period of SRU, this study was carried out to investigate the in-depth effect of SRU on the growth and development of E. ferox and to provide technical references for the increase in E. ferox yield, the improvement in E. ferox quality, and the simplification of fertiliser application. [ABSTRACT FROM AUTHOR]

Herein, the effects of electroslag remelting (ESR) and impurities in ESR slag on the composition, microstructure, and properties of lightweight steel with a nominal composition in wt% of Fe‐20Mn‐10Al‐1.5C are studied. These results can provide a reference for the production of such steels using ESR and the design of the composition of such steels. The results show that ESR can make the contents of Si increase and that of S decrease, make the grain size decrease, make the phase transformation of austenite at about 540 °C change from spinodal decomposition to ordered transformation, make the contents of MnS and SiO2 and inclusions greater than 5 μm decrease, make the distribution of inclusions homogenize, and make the shape of inclusions change from long strip with sharp corners to spherical shape. ESR can improve its strength, plasticity, and antiballistic penetration properties. [ABSTRACT FROM AUTHOR]

Different from conventional ferromagnetic methods, producing a spin-polarized current through electrical ways in spintronic devices can greatly increase operating speed, reduce power consumption, and improve device integration. Inspired by recent experimental progress on the synthesis of a heptauthrene molecule, we investigate its spin-dependent transport contacted with Au electrodes through first-principles calculations. By applying a gate voltage, the transmission can be switched between completely spin-up and spin-down polarized states, achieving an electrically controlled dual-spin filter. Furthermore, a fine tuning on the spin polarization, between 100% and − 100%, can also be realized, where the transport with any ratio of spin-up to spin-down electron quantities can be realized beyond the traditional devices. The peculiar transmission spectra and their shift are found to play crucial roles, where transmission peaks distribute on both sides of the Fermi level with opposite spin components. Such a spin-polarization modulating effect is found to be robust to the molecule-electrode contacting site, indicating it is an intrinsic feature of such systems. Moreover, the dimension of the device is at the single-molecule level, suggesting great application potential. [ABSTRACT FROM AUTHOR]

Byline: Yu-Hao. Wang, Pi-Hsiung. Wu, Hsing-Hao. Su, Chung-Yang. Wang, Lan. Hsu Background: Much attention has been focused on environmental risk factors and their roles in eczema development. In this regard, [...]