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Pollen, as an important component of Eucommia ulmoides (EUP), is rich in nutrients and is receiving increasing attention. At present, there are no reports on research related to the chemical composition and quality standards of EUP, and there are significant quality differences and counterfeit phenomena in the market. This study used a UPLC-QTOF-MS system to identify 49 chemical components in EUP for the first time. In the second step, 2,2-diphenyl-1-picrylhydrazyl (DPPH)-HPLC antioxidant activity screening technology was used to identify the main active components of EUP, quercetin-3-O-sophoroside (QSH), quercetin-3-O-sambubioside (QSB), and quercetin 3-O-neohesperidoside (QNH), and their purification, preparation, and structure identification were carried out. Third, molecular docking was used to predict the activity of these components. Fourth, the intracellular ROS generation model of RAW264.7 induced by H2O2 was used to verify and evaluate the activity of candidate active ingredients to determine their feasibility as Q-markers. Finally, a quality control method for EUP was constructed using the three selected components as Q-markers. The identification of chemical components and the discovery, prediction, and confirmation of characteristic Q-markers in EUP provide important references for better research on EUP and the effective evaluation and control of its quality. This approach provides a new model for the quality control of novel foods or dietary supplements.

Nowadays, the Internet of Video Things (IoVT) is growing rapidly in terms of quantity and computation demands. In spite of the higher local computation capability on visual processing compared to conventional Internet of Things devices, IoVT devices need to offload partial visual processing tasks to the mobile edge computing (MEC) server wirelessly due to its larger computation demands. However, visual processing task offloading is limited by uplink throughput and computation capability of the MEC server. To break through these limitations, a novel non-orthogonal multiple access (NOMA)-assisted IoVT framework with multiple MEC servers is proposed, where NOMA is exploited to improve uplink throughput, and MEC servers are co-located with base stations to provide enough computation capability for off-loading. In the proposed framework, the association strategy, uplink visual data transmission assisted by NOMA, and division of the visual processing tasks as well as computation resource allocation at the MEC servers are jointly optimized to minimize the total delay of all visual processing tasks, while meeting the delay requirements of all IoVT devices. Simulation results demonstrate that significant performance gains can be achieved by proposed joint optimization with NOMA transmission and multi-MEC offloading in the heterogeneous IoVT network.

To relieve the stress on channel estimation and decoding complexity in cell-free massive multiple-input multiple-output (MIMO) systems, user grouping problem is investigated in this paper, where access points (APs) based on time-division duplex (TDD) are considered to serve users on different time resources and the same frequency resource. In addition, when quality of service (QoS) requirements are considered, widely-used max-min power control is no longer applicable. We derive the minimum power constraints under diverse QoS requirements considering user grouping. Based on the analysis, we formulate the joint power and user grouping problem under QoS constraints, aiming at minimizing the total transmit power. A generalized benders decomposition (GBD) based algorithm is proposed, where the primal problem and master problem are solved iteratively to approach the optimal solution. Simulation results demonstrate that by user grouping, the number of users served in cell-free MIMO systems can be as much as the number of APs without increasing the complexity of channel estimation and decoding. Furthermore, with the proposed user grouping strategy, the power consumption can be reduced by 2-3 dB compared with the reference user grouping strategy{, and by 7 dB compared with the total transmit power without grouping., Comment: 15 pages, 9 figures, 41 conference

Pharmacological relevance Paclitaxel (PTX) is currently the only botanical drug that can control the growth of cancer cells. Paclitaxel is widely used in the treatment of breast cancer, ovarian cancer, uterine cancer, non-small cell lung cancer and other cancers. Aim Folate receptor and integrin α v β 3 are highly expressed on the surface of human breast cancer cells MCF-7. Folic acid and arginine-glycine-aspartate (Arg-Gly-Asp, RGD) tripeptide sequence have a high affinity for folate receptor and integrin α v β 3, respectively. To enhance the effect on breast cancer, we constructed the folate acid and RGD peptide dual-targeted (MSNs-NH2-FA-RGD) drug-carrier based on mesoporous silica nanoparticles. Methods The structure of mesoporous nanocarriers was characterized by Fourier transform infrared spectroscopy, nitrogen adsorption-desorption analysis, transmission electron microscopy, laser particle size analyzer, and thermogravimetric analysis. Paclitaxel was chosen as the model drug. The targeting-ability was verified by observing the uptake of mesoporous carriers loaded with rhodamine in MCF-7, MCF-10A, and HeLa cells using a fluorescence microscope. The cytotoxicity of the blank carrier MSNs-NH2-FA-RGD and the efficacy of the drug carrier PTX@MSNs-NH2-FA-RGD were assessed by cell experiments. Results The characterization showed successful construction of a dual-targeted mesoporous silica nanocarrier. Obvious differences were detected in the fluorescence intensity of the three cell lines. The results of the pharmacological tests indicated that the blank nanoparticles do not cause any apparent toxicity on these cells. The IC50 of free PTX and PTX@MSNs-NH2-FA-RGD on MCF-7 cells line treated for 48 h were 35.25±2.57 ng·ml-1 and 22.21±3.4 ng·ml-1 respectively, which indicated that the inhibitory efficacy of PTX@MSNs-NH2-FA-RGD on MCF-7 was 1.6 times than that of free PTX. Conclusions The dual-targeted nanocarrier MSNs-NH2-FA-RGD could target breast cancer cells, and sever as a potential candidate in future of drug development.

In this study, ginger juice powders (GJPs) were obtained from ginger juice using vacuum drying, spray drying, vacuum microwave drying (VMD), and freeze‐drying (FD). The physical properties (water content, dissolving time, and color), chemical compositions (total volatiles, gingerols and shogaol, total phenolic content [TPC]), antioxidant activity, and aerobic bacteria content of the GJPs/redissolved ginger juice were determined and the effect of the drying processes on ginger juice was evaluated. The result showed that FD was optimal at retaining the color, gingerols, shogaol, and total volatiles of the ginger juice, while both VMD and FD could retain a high yield of TPC and the antioxidant activity of the ginger juice. It was also found that all the drying methods were effective in reducing the total aerobic bacteria of the ginger juice. This study proved that the four drying methods had very different effects on the quality of the ginger juice, among which FD was optimal for processing ginger juice. PRACTICAL APPLICATIONS: In this study, four processing methods of ginger juice were compared by investigating the physical properties (water content, dissolving time, and color), chemical compositions (total volatiles, gingerols and shogaol, total phenolic content), antioxidant activity, and aerobic bacteria content of the different ginger juice powers prepared. The results will provide new reference for processing ginger.

To alleviate severe inter-user interference in Non-orthogonal multiple access (NOMA) systems, in practice, several users are grouped together for NOMA transmission and orthogonal resources are allocated among different groups. In this paper, we investigate uplink NOMA scenarios with multiple base stations, where user association is jointly considered with user grouping. It is worth noting that a user prefers to be associated with the base station where it can be assigned into a group with less inter-user interference. Furthermore, different users have different quality-of-service (QoS) requirements. Based on these observations, we firstly quantitatively analyze the extra transmit power that a user brings to the others in the same group under QoS constraints, i.e., externalities, and derive an externality function to indicate interference among users in uplink NOMA. Then, we obtain a game model for the joint user association, grouping and power allocation (JAGP) problem in uplink NOMA systems and prove that it is an exact potential game, with the goal to minimize total transmit power. Furthermore, we prove the existence of Nash Equilibrium (NE) as well as the finite improvement property (FIP) of this game. In addition, the NE of this game is proved to be Pareto-optimal. A heuristic algorithm is proposed to find the solution to the JAGP problem by achieving the NE of the proposed game, which convergence is guaranteed by FIP. Simulation results show that the proposed algorithm can considerably reduce the total transmit power compared with existing schemes.

To meet the performance and complexity requirements from practical deployment of non-orthogonal multiple access (NOMA) systems, several users are grouped together for NOMA transmission while orthogonal resources are allocated among groups. User grouping strategies have significant impact on the power consumption and system performance. However, existing related studies divide users into groups based on channel conditions, where diverse quality of service (QoS) and interference have not been considered. In this paper, we focus on the interference-aware user grouping strategy in NOMA systems, aiming at minimizing power consumption with QoS constraints. We define a power consumption and externality (PCE) function for each user to represent the power consumption involved by this user to satisfy its QoS requirement as well as interference that this user brings to others in the same group. Then, we extend the definition of PCE to multi-user scenarios and convert the user grouping problem into the problem of searching for specific negative loops in the graph. Bellman-Ford algorithm is extended to find these negative loops. Furthermore, a greedy suboptimal algorithm is proposed to approach the solution within polynomial time. Simulation results show that the proposed algorithms can considerably reduce the total power consumption compared with existing strategies., Comment: 9 pages, 7 figures, INFOCOM 2019

With the explosive increment in mobile users and mobile devices, nowadays network infrastructures are foreseen to be much more struggle in handling the vast mobile video traffic in the network. To meet this challenge, small-cell base stations (SBSs) are introduced in heterogeneous networks (HetNets) to support high data rate services in the fronthaul. However, HetNets still suffer from backhaul bandwidth shortage. Caching is a promising way to relieve the bandwidth burden on the backhaul. However it may fail in improving user's quality of experience (QoE) in video services. The reason is that, without a corresponding power allocation strategy in the fronthaul, users are unlikely to be allocated sufficient power to receive the higher quality version of videos, which in return leads to the waste of the limited caching space. On the other hand, the distinct layered feature of scalable video encoding (SVC) videos allows us to do layer-wise caching to further promote the cache utilization efficiency. Thereupon, a nature idea is to combine the power allocation strategy and the layer-wise caching strategy to effectively utilize the limited power and cache space of SBSs, so that the limited bandwidth of backhaul can be saved while user's QoE can be improved. In this work, we take the layered feature of SVC videos into account to jointly optimize these two strategies, aiming to maximize user's QoE. A simulated annealing based algorithm is proposed to solve the formulated problem. Simulation results show that, by doing so, the cache-hit ratio is increased while the limited backhaul bandwidth can be saved. Moreover, user's QoE has been significantly improved compared to traditional caching strategies

Rhizoma coptidis (RC) has been used as an herbal medicine in China for over one thousand years, and it was subjected to specific processing before use as materia medica. Processing is a pharmaceutical technique that aims to enhance the efficacy and/or reduce the toxicity of crude drugs according to traditional Chinese medicine theory. In this study, the chemical profiles of RC, ginger juice processed RC (GRC), and water processed RC (WRC) was determined to reveal the mechanism of processing of RC. UPLC-QTOF-MS analysis of methanol extract of RC, GRC, and WRC has been conducted to investigate the effect of processing on the composition of RC. HPLC-PDA was used to determine the variance of total alkaloids and seven alkaloids of RC during the processing. The volatiles of RC, GRC and ginger juice were separated by distillation, the change of volatiles content was recorded and analyzed, and the qualitative analysis of the volatiles was carried out using GC-MS. The microstructures of RC, GRC and WRC were observed using a light microscope. Results showed that ginger juice/water processing had limited influence on the composition of RC’s methanol extract, but significant influence on the content of some alkaloids in RC. Ginger juice processing significantly increased (p < 0.05) the volatiles content of RC and changed the volatiles composition obviously. Processing also had an influence on the microstructure of RC. This research comprehensively revealed the mechanism of ginger juice processing of RC.