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Due to the research paradigm of the conventional Visible Light Communications (VLC), researchers usually assume that the optical sources follow the Lambertian spatial radiation characteristics. Objectively, this assumption ignores that the potential heterogeneous optical beams based on distinct beams, and the essential exploration for the coverage of the VLC based on the above heterogeneous optical beams. To address the issue, we comprehensively consider the distinct non-Lambertian optical beams characteristics of commercial light emitting diodes, and provide several potential heterogeneous optical beams configuration. Simultaneously, in typical indoor scenario, the coverage characteristics are compared between the conventional Lambertian beam based transmitter configuration and the proposed heterogeneous optical beams configuration. Numerical results show that, compared with the well-known Lambertian transmitter design, the proposed heterogeneous optical beams configuration could provide up to 1.97 dB minimum Signal-to-Noise Ratio (SNR) gain, and modify the SNR fluctuation extent from about 22.75 dB of original design to about 15.33 dB in the heterogeneous configuration. Moreover, via the heterogeneous configuration, the weak coverage proportion with lower than 30 dB SNR, is reduced to about 7.23% from original proportion of about 13.2%. Therefore, to indoor spatial coverage, the effects induced by the heterogeneous optical beams are verified preliminarily.

Objective To analyze the clinical effect of acupuncture combined with thoracic paravertebral block (TPVB) in the treatment of pain and complications of the patients with intercostal nerve transfer and general anesthesia. Methods Eighty-eight patients with intercostal nerve transfer were randomized into three groups: 34 cases with patient controlled intravenous analgesia (PCIA) just after operation in group A, 28 cases with TPVB given when entering the operation and(PCIA) at the end of operation in group B, and 26 cases with TPVB and(PCIA) combined with acupuncture in group C. Acupuncture analgesia was used in group C with electroacupuncture stimulated for 20 minutes on points of Zhigou, Houxi, Hegu and bilateral Neiguan just the day before operation. Incidence of postoperative nausea and vomiting and the postoperative dosage of analgesic fentanyl were recorded. The indices related with analgesia including β-endorphin (β-EP), interleukin-6 (IL-6), tumor necrosis factor-α(TNF-α), 5-hydroxytryptamine (5-HT) and cortisol were detected using ELISA method before and after operation and compared among 3 groups. Results The dosage of fentanyl was lower in group C than those in group A and B significantly (P

Few studies of cryogenic treatment were focused on nonferrous alloys, such as magnesium alloy. In this work, the effect of cryogenic treatment (77 K) before extrusion on microstructure and mechanical properties of ZK60 alloy was investigated. The results showed that many fine G.P. zones were formed during the cryogenic treatment and then grew to short fine β1′{\beta }_{1}^{^{\prime} } precipitates when heating before extrusion. These precipitates pinned dynamic recrystallized grain boundaries in the subsequent extrusion, resulting in fine gains and dispersed spherical precipitates. By the cryogenic treatment before extrusion, the extruded ZK60 alloy showed good tensile strength and elongation balance. Especially, elongation was improved by 29%.

Plants are highly susceptible to abiotic stresses, particularly heat stress during the reproductive stage. However, the specific molecular mechanisms underlying this sensitivity remain largely unknown. In the current study, we demonstrate that the Nuclear Transcription Factor, X‐box Binding Protein 1‐Like 1 (NFXL1), directly regulates the expression of DEHYDRATION‐RESPONSIVE ELEMENT‐BINDING PROTEIN 2A (DREB2A), which is crucial for reproductive thermotolerance in Arabidopsis. NFXL1 is upregulated by heat stress, and its mutation leads to a reduction in silique length (seed number) under heat stress conditions. RNA‐Seq analysis reveals that NFXL1 has a global impact on the expression of heat stress responsive genes, including DREB2A, Heat Shock Factor A3 (HSFA3) and Heat Shock Protein 17.6 (HSP17.6) in flower buds. Interestingly, NFXL1 is enriched in the promoter region of DREB2A, but not of either HSFA3 or HSP17.6. Further experiments using electrophoretic mobility shift assay have confirmed that NFXL1 directly binds to the DNA fragment derived from the DREB2A promoter. Moreover, effector–reporter assays have shown that NFXL1 activates the DREB2A promoter. The DREB2A mutants are also heat stress sensitive at the reproductive stage, and DEREB2A is epistatic to NFXL1 in regulating thermotolerance in flower buds. It is known that HSFA3, a direct target of DREB2A, regulates the expression of heat shock proteins genes under heat stress conditions. Thus, our findings establish NFXL1 as a critical upstream regulator of DREB2A in the transcriptional cassette responsible for heat stress responses required for reproductive thermotolerance in Arabidopsis. [ABSTRACT FROM AUTHOR]

BACKGROUND Atomic Fluorescence Spectrometry (AFS) has advantages of high sensitivity, simple structure and easy operation, but the digestion process of the standard analysis method for determination of Se in soil is cumbersome and readily produces interference. OBJECTIVES To evaluate the applicability of Se determination in soil and sediment by water bath digestion/AFS, and uncover the main interference and elimination methods. METHODS Based on the standard method of GB/T 22105-2008, boiling water bath of aqua regina was used to digest Se in soil and sediment. Four treatments, including Fe3+, concentrated hydrochloric acid, Fe3+with concentrated hydrochloric acid, and water bath solution, were used to eliminate the interference of Cu2+ and Pb4+. RESULTS The detection limit of Se by this method was 0.008mg/kg, the relative standard deviation of the test reference materials was 0.5%-11%, and the relative error was -16.3%-9.5%, better than the detection limit (0.01mg/kg), precision (0.79%-23.1%) and accuracy of the industry standard HJ 680-2013. CONCLUSIONS According to the experiment, it is proposed to add concentrated hydrochloric acid to the water bath digestion solution without adding thiourea-ascorbic acid. By increasing the acidity and Cl- concentration of the solution and keeping the concentration of hydrochloric acid in the sample higher than 23%, the reduction of Cu2+ to Cu0 and Pb4+ to form PbH4 can be inhibited. The negative interference of Cu and the positive interference of Pb are effectively reduced, and the precision and accuracy of Se measured by AFS are improved.