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PTP70-2, a novel polysaccharide isolated from Polygala tenuifolia in our previous publication, exhibits potential anti-inflammatory effects. Here, we investigate the mechanisms underlying these effects and the neuroprotective activity of PTP70-2 in lipopolysaccharide (LPS)-damaged BV2 microglial cells and neuroinflammation-injured primary cortical neurons. The results suggest that PTP70-2 dramatically reduces the LPS-stimulated inflammatory cytokines overexpression, as well as down-regulates the levels of TLR4-, MyD88-, and NF-κB-related proteins. The effect of PTP70-2 in down-regulation of proinflammatory cytokines and downstream proteins implicated in MyD88 and NF-κB signaling is related to the TLR4 pathway. Furthermore, this effect is enhanced by the co-incubation of BV2 cells with PTP70-2 and TAK242, a TLR4 inhibitor, before exposure to LPS. Importantly, PTP70-2 prevents neuroinflammation-induced neurotoxicity by mitigating ROS overproduction and MMP dissipation. Overall, the PTP70-2's anti-neuroinflammation and neuroprotection are involved to the modulation of the TLR4-mediated MyD88/NF-κB signaling pathway.

The water–energy–food (W-E-F) nexus approach has become the basis for a host of many methods addressing the security of global resources, whose methods are often nonparametric, due to the complex and indefinable relationship among the three. In this work, the nonparametric evaluation method data envelopment analysis (DEA) is further extended to a three-stage dual-boundary network model (TD-NDEA) for dealing with the “black box” problem in W-E-F Nexus. In the empirical study, the TD-NDEA method is applied to assess the efficiencies of W-E-F nexus in 13 selected cities of Jiangsu Province in China, where W-E-F nexus is innovatively decomposed into three stages, “W-E,” “WE-F,” and “WEF.” External factors such as labor force, urbanization, and economy are included in the assessment. On this basis, environmental governance and policy interventions are utilized as indicators of eco-sustainability to reshape the third stage as “WEF-Eco.” It is perceived from the numeric analysis that (i) regional disparities in the efficiencies of W-E-F nexus expand significantly; (ii) compared with the labor force, urbanization, and economy are more remarkable toward influencing the efficiencies; and (iii) ecological sustainable planning plays an effective role in reducing regional heterogeneity and speeding up the process of regional coordination. Based upon the findings, relevant policy recommendations are carefully designed.

In view of the fact that there is no practical standards or methods of RF conducted interference measurement of the high power system at present and that different standards may lead to conflicting conclusions, the RF conducted interference measuring equivalent circuit model is established. Meanwhile, the fundamental relationship between current and voltage method is obtained by the theoretical calculation, and the conversion formula of two methods between the measurement results and the standard limit are given, which proves the voltage measurement is more reasonable than current measurement. Laboratory test results verify the accuracy of the theoretical analysis. It provides technical support for the scientific evaluation of electromagnetic compatibility of equipment and the formulation of RF conducted interference standards for high-power systems.

In this paper, some problems are discussed on the reconstruction of semi-anechoic chamber in a non-standard size shielding enclosure, such as structural, grounding, lighting, ventilation system and selection of shielding material. The reconstructed semi-anechoic chamber has good performance, the two indicators of shielding effectiveness and background noise meet the requirement in GJB151A-1997 and GJB151B-2013, EMC test can be conducted in the new semi-anechoic chamber. It is feasible and cost-effective to transform a non-standard size old shielding enclosure into a semi-anechoic chamber. This paper has some reference for the similar transformation needs.

The Belt and Road initiative has been gaining attention internationally since its proposal. This study applies complex network theory to the Belt and Road countries’ exchange rate markets by constructing a correlation network for these markets using the detrended cross-correlation coefficient (DCCA cross-correlation coefficient). Results show that the Belt and Road countries’ exchange rate network (BREN) 1 exhibits a small-world effect and robustness. The network is divided into three clusters by factional analysis. The three clusters correspond to three regions: West Asia, Central Asia and Europe, and Southeast Asia. The cohesion subgroup density between Central Asia and Europe and West Asia is high, and the inter-correlation of the Central Asia and Europe is strong. Moreover, the CNY’s position in the BREN has been significantly improved since the policy was proposed.

This paper first analyzes the ionosphere loss model is established based on analytic method, a nonlinear sea spectrum as the theoretical foundation of ship swaying in the waves of the sea model is set up, and then the numerical method is adopted to establish the waves with the wind blowing the typical three-dimensional model, and converted into a mathematical model of ship longitudinal and transverse swing and using high frequency approximation method to calculate the surface of radio navigation signal amplitude and phase of contribution, finally through the simulation data post-processing and statistical analysis, got the Marine radio navigation signals compensation strategy and specific methods.

A novel three-dimensional (3-D) frequency selective surface (FSS) exhibiting wide- band and highly selective bandpass response is presented. The proposed FSS consists of a two- dimensional periodic array of vertical, shielded, and suspended striplines. By combining the high- pass property of the periodic array of waveguides with bandstop resonances from the inserted U-shaped striplines, a quasi-elliptic bandpass frequency response over a wide-band from 8.4 GHz to 16.2 GHz is achieved with a 3 dB frequency bandwidth of 63% and a sharp rejection skirt.

This paper presents a polarization converter that a linearly polarized incident wave can be converted into a circularly polarized wave. The proposed structure is composed of a two-dimensional periodic arrangement of dielectric-filled substrate integrated waveguide cavities (SIWC) in unit-cell of which double-layer slot frequency selective surface (FSS) cascaded with dielectric layers. Through the coupling of the input and output waves with slots on the layers, two linearly polarized outgoing waves with orthogonal polarization can be transmitted. When the two orthogonally polarized components are combined and adjusted with equivalent amplitude and 90° phase difference, they can be synthesized into circularly polarized wave.

Polygala tenuifolia Willd. is a vital industrial-export plant in Southeast Asia, particularly China. The rhizomes of P. tenuifolia are known for their nootropic and cognition-improving effects. As such, they have been widely used in traditional Chinese medicine (TCM) for centuries. However, the active constituents responsible for the biological benefits of P. tenuifolia remain unclear. In this study, P. tenuifolia rhizomes were extracted with hot water and then isolated and purified using diethylaminoethyl cellulose (DEAE-C) 52 and Sephacryl S-100 chromatographic columns. A homogeneous heteropolysaccharide (PTP70-2) with a relative molecular weight (MW) of 65.2 kDa was obtained. Based on monosaccharide composition, Fourier-transform infrared spectroscopy (FTIR), gas chromatography–mass spectrometry (GC/MS), and nuclear magnetic resonance (NMR) analyses, PTP70-2 was composed of 11 residues: →5)-α-L-Araf-(1→, →2,5)-α-L-Araf-(1→, →3,5)-α-L-Araf-(1→, →6)-β-D-Galp-(1→, →6)-α-L-Manp-(1→, →4)-β-D-Galp-(1→, →4,6)-β-D-Galp-(1→, α-L-Araf, α-L-Rhap, α-D-GlcAp, and α-L-Manp, at a molar ratio of 7.3:1.4:5.2:15.0:2.1:2.4:5.6:8.2:1.3:1.5:1.3. Scanning electron microscopy (SEM) results showed that PTP70-2 had an irregular surface with scattered strips. Pharmacological assessments showed that PTP70-2 inhibited the production of nitric oxide (NO) in lipopolysaccharide (LPS)–induced pro-inflammatory BV2 microglial cells, and the inhibitory effect of 3.08 μM PTP70-2 was even greater than that of the positive control, 12.5 μM minocycline. In addition to NO, PTP70-2 significantly suppressed the expression of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Based on these results, the authors believe PTP70-2 is a new anti-neuroinflammatory agent that has great potential for the treatment and prevention of Alzheimer disease.

Improving carbon emission efficiency in China is conducive to achieving the win-win situation of economic growth, energy conservation and emissions reduction but it is also crucial to be able to accurately measure it. Based on an improved non-radial directional distance function, the paper constructs a new meta-frontier total-factor carbon emission efficiency index by considering technology heterogeneity. In order to reveal the source of efficiency losses, we look at the two dimensions of production technology and management so as to be able to then decompose the meta-frontier carbon emission inefficiency into technology gap inefficiency and managerial inefficiency. Following this, we measure the meta-frontier total-factor carbon emission efficiency of China’s 31 manufacturing industries from 2012 to 2016 and analyze the root causes of their carbon emission inefficiency. The results show that, during the investigation period, the meta-frontier total-factor carbon emission efficiency of China’s manufacturing industry was low and there was significant industrial heterogeneity. The meta-frontier total-factor carbon emission efficiency of high-tech industry was the highest, followed by that of middle-tech industry, with the lowest being low-tech industry. The root cause of carbon emission inefficiency in China’s manufacturing industry mainly lies in the low level of management. With improvements in industrial technological levels, managerial inefficiency gradually increases as a percentage of the total even though technology gap inefficiency gradually decreases. Based on the above results, we suggest measures to improve carbon emission efficiency for those various manufacturing industries characterized by different technology levels.

The response of a receiving antenna to the high power microwave irradiation is analyzed by using the finite integration technique (FIT). Typical excitation signals are applied to examine the effect of the excitation to the response. The results reveal that the waveform of the response signal is mainly decided by the excitation signal and the operating frequency band of the receiving antenna.

The ship-borne VHF communication antenna is one of the important transmitting and receiving antennas on the ship. The antenna directivity directly affects the performance of the whole communication system. In this paper, we adopt the method of MoM/PO to predict the radiation of shipboard VHF antenna under different conditions. Based on simulation data, we summarized the effect of ship superstructure, frequency, antenna height, and sea conditions on the performance of shipboard VHF communication antenna, which has a certain guiding significance for the design and layout of ship-borne antenna.

With the development of power electronics technique, more and more high-power electronics devices are applied in the power system. EMI filters are spread used to reduce the electromagnetic interference generated by these devices. But it is very difficult to manufacture high-voltage filter capacitors and heavy-current filter inductors. Several low-power filters can be connected in series or in parallel to realize a high-power filter. The insertion loss calculation method of such filter is researched in this paper. First, the relationship between the insertion loss (IL) and the two-port network parameters has been derived. Then the insertion loss of multiple filters connected in series and in parallel is researched by experiments. Finally, two filters connected in parallel were designed for a high-power inverter. The measurement results verified the validity of the theoretical derivation.

Current probe is a detection method commonly used in electromagnetic compatibility. With the development of power electronics technology, the power level of power conversion devices is constantly increasing, and the power current of the electric energy conversion device in the electromagnetic launch system can reach 10kA. Current probe conventionally used in EMC (electromagnetic compatibility) detection cannot meet the test requirements on high current system due to the magnetic saturation problem. The conventional high current sensor is also not suitable for the RF (Radio Frequency) interference current measurement in high current power device due to the high noise level in the output of active amplifier. In this paper, a passive flexible current probe based on Rogowski coil and matching resistance is proposed that can withstand high current and has low noise level, to solve the measurement problems of interference current in high current power converter. And both differential mode and common mode current detection can be easily carried out with the proposed probe because of the probe’s flexible structure.

In power electronic devices, the winding temperature of the transformer in operation needs to be monitored in real time. But the Electromagnetic Interference(EMI) problems cause the measured winding temperature fluctuates anomalously. In this paper, the 10MVA transformer in the cabinet of a transformer rectifier is studied as a specific case, the temperature measurement circuit of the transformer winding is introduced, according to which the causes of winding temperature fluctuation is analyzed. Finally, the solution of the winding temperature fluctuation is proposed and verified by experiments.