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Network assisted with reconfigurable intelligent surface is a kind of low-cost and low-power solution which can provide stable, continuous and ubiquitous connection to satisfy deep coverage requirements in 5G-Advanced (5G-A) and 6G era. A kind of reconfigurable intelligent surface assisted high and low frequency collaborative network architecture based on the positioning analysis of reconfigurable intelligent surface technology was proposed. The proportion of base station and reconfigurable intelligent surface collaborative deployment was analyzed. Furthermore, a interference reduction based on bandwidth design scheme was proposed to reduce adjacent frequency interference. System level performance simulation of network assisted with reconfigurable intelligent surface was verified to analyze the impact of reconfigurable intelligent surface deployment location and number of array elements under different UE distribution conditions. The simulation results show that the RIS-assisted network can significantly improve the edge and weak coverage area, so as to improve the network performance of the whole communication system.

Rubus suavissimus is mainly distributed in Guilin, Liuzhou, Wuzhou and other regions in Guangxi Zhuang Autonomous Region, so it is called as “Guangxi tiancha” in China. R. suavissimus, together with Siraitia grosvenorii and Stevia rebaudianastevia are praised as three famous sweet plants in Guangxi Zhuang Autonomous Region. Zhuang and Yao people use the leaves of R. suavissimus as a tea to treat diabetes, and it is known as the “divine tea” of Yao medicine. Therefore, R. suavissimus is a combination of sugar, tea and medicine, which has great potential for the development of food and medicine. In order to investigate the secondary metabolites with α-glucosidase inhibitory activity from R. suavissimus, herein, the extraction, separation and purification of secondary metabolites were performed on the leaves of R. suavissimus. The structures of purified compounds were determined based on the data of mass spectrometry (HR-ESI-MS) and nuclear magnetic resonance (1H NMR and 13C NMR). In addition, the α-glucosidase inhibitory activity of the purified compounds were evaluated by pharmacological methods simultaneously. The results were as follows: (1) Ten compounds were purified and their structures were elucidated as rubusoside (1), kaempferol 3-O-robinobioside (2), gallic acid (3), dihydrodehydroconiferyl alcohol (4), 5-methoxydihydrodehydroconiferyl alcohol (5), brevifolincarboxylic acid (6), steviolmonoside (7), steviol (8), 16α, 17-dihydroxykaurane (9), and quercetin 3-O-β-D-galactopyranoside (10). Among them, compounds 2, 4, 5 and 9 were isolated from R. suavissimus for the first time. (2) Compounds 2, 3, 5, 6 and 10 showed strong inhibitory activity on α-glucosidase. The IC50 values of compounds 2, 3, 5, 6 and 10 were (0.14 ± 0.03) mg·mL-1, (0.36 ± 0.02) mg·mL-1, (0.44 ± 0.01) mg·mL-1, (0.53 ± 0.04) mg·mL-1 and (0.14 ± 0.03) mg·mL-1 respectively, which were stronger than the positive control acarbose with the IC50 values as (0.69 ± 0.02) mg·mL-1. Thus, compounds 2, 3, 5, 6 and 10, which were isolated from the leaves of R. suavissimus, could be a potential α-glucosidase inhibitors based on their bioactivity results. Compounds with α-glucosidase inhibitory activity from R. suavissimus will provide the basis for development of related hypoglycemic products.

Aimed at the low frequency of traditional ultrasonic transducers in low frequency domain,a new theoretical model of microbridge was designed,with analysis and research of the mechanical behavior. Solid modeling,modal analysis and electrostatic analysis were carried out with COMSOL 5. 4 for the silicon-based microbridges of the antiferroelectric thick film,which can produce the effect of phase-transition induced strain. Applied with the orthogonal design,the reasonable structure sizes of the microbridge component with small stress and large frequency were obtained. They can provide an important basis for the following fabrication. When the microbridge is 800 μm（ L） × 100 μm（ W）,the corresponding stress is 0. 352 GPa and the resonant frequency equals to 115. 19 kHz,which is superior to traditional ultrasonic transducers in the aspect of better performance based on the smaller sizes.

In order to study the mechanism of fatigue failure of harmonic reducer flexspline,by using ANSYS n Code Design Life 15. 0 software,the fatigue analysis of flexspline is carried out based on the results of finite element analysis. Comparing the analysis results with the engineering fatigue damage of flexspline,it is found that tooth circle and the bottom of the flange are much easier for fatigue failure,a basis for the design of flexspline is provided.

Objective: The research regarding the central mechanism of acupuncture deqi (arrival of qi ) based on functional magnetic resonance imaging (fMRI) in recent 10 years was analyzed to summarize existing research achievements and experience., Methods: The literature regarding fMRI-based deqi research published from January of 2007 through December of 2016 in CNKI and PubMed databases was collected. The research content and methods, including research design, inclusion criteria, acupoint selection and deqi evaluation, were analyzed., Results: Totally 18 articles regarding the central mechanism of acupuncture deqi based on fMRI was included. According to research content, the literature was divided into two categories: deqi research and deqi sensation research. In deqi research, the differences of deqi and not deqi on brain functional activity were compared to summarize the central response pattern of deqi ; in deqi sensation research, the differences of different sensations and intensities of deqi on central response were compared to explore the effects of different sensations and intensities of deqi on brain functional activity. In recent 10 years, the number of research gradually increased, and the type of design was various, mainly RCT and paired design. The majority of participants was healthy people, and single acupoint was the focus of researches, including Zusanli (ST 36), Waiguan (TE 5), Hegu (LI 4), etc. The evaluation of deqi was based on visual analogue scale (VAS). The research contents were mainly the effects of deqi and not deqi and different deqi sensations on brain function activities. The present studies confirmed that deqi and not deqi as well as different deqi sensations had different impacts on brain functional effects, and different acupoints had specific activated brain areas. There was a positive correlation between the degree of deqi and the intensity of the activation of brain regions. Furthermore, tingling sensation was not included to deqi sensations., Conclusion: The number and quality of fMRI-based deqi research need to be improved; the research content is simple, and research method is in exploratory stage. The results obtained in the literature are the phenomena of deqi in the central level, and it is imperative to summarize the essential link between deqi and the central effect through these phenomena to reveal the mechanism of deqi . The specific impact of deqi for brain function needs more clinical exploration.

Objective: To evaluate the effects of needling depth on clinical efficacy of lumbar disc herniation (LDH)., Methods: Ten electronic databases, including China National Knowledge Infrastructure (CNKI), VIP Database, Chinese Biomedical Literature Database (CBM), Wanfang Database, MEDLINE, CENTRAL, CINAHL PLUS, AMED, Embase, PsycINFO, and 6 registry platforms of clinical trials were searched. All randomized controlled trials (RCTs) that compared the effect of needling depth on clinical efficacy of LDH were collected; in addition, the reference lists of the studies included were hand searched. Data were extracted independently by two reviewers. RevMan 5.3 was applied to carry out statistical analysis., Results: Totally 8 716 articles were retrieved, and 10 RCTs were included after screening, involving 1 116 patients. The results showed the effects of deep acupuncture onrelievingpain, reducing the Oswestry disability index (ODI), improving total effective rate and Japanese Orthopaedic Association (JOA) were superior to those of shallow acupuncture in patients with LDH., Conclusion: It is preliminarily indicated that deep acupuncture is helpful to improve the therapeutic effect of LDH; however, due to the low research quality and small sample size, the evidence is insufficient, and more high-quality researches are needed to further confirm the results.

The paper is a systematic review on the efficacy of acupuncture manipulation on primary dysmenorrhea. Ten medical literatures database at home and abroad were retrieved, including CNKI, VIP, CBM, WANFANG, MEDLINE, Cochrane, CENTRAL, CINAHL PLUS, EMBASE, AMED and PsycINFO, as well as 6 clinical trial registration platforms. All of randomized controlled trials (RCTs) on primary dysmenorrhea treated with different acupuncture manipulations were collected. The data were extracted by two persons. Finally, RevMa 5.3 software was used for statistical analysis. Totally, 5 148 pieces of literature were retrieved and 8 pieces on RCTs were screened with 644 cases included. According to the results of statistical analysis on the total effective rate and other indicators of pain degree, it was showed that the effects of the manipulation with filiform needle, deep puncture with strong stimulation, and specific reinforcing and reducing needling technique were better than those without manipulation applied or with shallow puncture and weak stimulation and even needling technique in the treatment of primary dysmenorrhea. It is believed initially that acupuncture manipulation contributes to the improvement of the therapeutic effects of primary dysmenorrheal, but much higher quality studies are required for the further confirmation. Protocol registration number:PROSPERO:CRD42016038515.

The effects of deqi (arrival of qi ) on acupoint effects in patients with primary dysmenorrhea (PD) were evaluated.Ten literature databases,including China National Knowledge Infrastructure (CNKI),VIP Database,Wanfang Database,Chinese Biomedical Literature Database (CBM),Cochrane Library CENTRAL,MEDLINE,Embase,AMED, CINAHL Plus,PsycINFO were selected.In addition,5 registers of ongoing trials,the reference lists of included articles and grey literature website OpenGrey were added.The search time was from date of database establishment to August 2016;no restrictions were made on language or status of publication.All randomized controlled trials (RCTs) and quasi-randomized controlled trials (q-RCTs) which compared the effects of deqi and non- deqi on PD or compared the effects of different deqi elements on PD were included.The research quality was assessed according to Cochrane bias risk evaluation tool 5.1.0.The RevMan 5.3.5 was applied for quantitative analysis if insignificant clinical heterogenicity with I 2 ≤ 75%,otherwise the results was summarized by qualitative analysis.As a result,6 RCTs involving 645 patients were included.Because of considerable clinical heterogeneity,only qualitative analysis was performed,which indicated ① acupuncture could reduce pain and anxiety regardless of deqi ,and the effects of deqi on pain relief were superior or equivalent to that of none- deqi ,and the effects of deqi on anxiety relief were similar to that of none- deqi ;② the more intensity of deqi and higher number of acupoints selected,the better effects on pain alleviation,symptom relief and pain duration;③ the higher rate of deqi had a better acupoint effect on alleviating anxiety,but was not on pain relief;④ deqi appeared early and propagated to affected area could lead to faster onset on pain relief;⑤ the effects on relieving pain and symptoms was better when warm sensation in deqi or qi reaching affected area.Due to the few number,low quality and potential bias of included studies,it was not sufficient to draw clear conclusion regarding the effects of deqi on PD patients.This study protocol was registered in PROSPERO (CRD42016038518).

An oxide ceramic coating can be formed on the surface of magnesium alloy by micro-arc oxidation so that the corrosion resistance of the magnesium alloy can be enhanced.In this paper,ageneral overview of the surface treatment of micro-arc oxidation on the surface of magnesium alloy is presented,the related research on the treatment of several kinds of magnesium alloys is introduced in detail,and a brief introduction of biological activity of magnesium alloy due to micro-arc oxidation is given.Finally,the technical advantages and existing problems are summarized.