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Dielectric response test is a non-destructive and highly sensitive tool for insulation characterization, it requires a high-precision micro-current measurement circuit, which can meet the requirements of field with complex electromagnetic interference and large temperature change. Ultra low bias current amplifiers are commonly used in micro-current measurements to complete I-V transformation. However, bias and offset currents are very susceptible to temperature. The test process is easily disturbed by external power frequency and electromagnetic noise in the form of radiation. In this paper, the principle of feedback resistance method in micro current test is analyses. At the same time, this paper analyses the effect of the error caused by the amplifier and temperature. On the basis of error analysis, a novel current test topology is proposed, which can effectively suppress the power frequency interference and temperature drift of chip. Through the introduction of differential architecture, the purpose of high accuracy current measurement under limited component accuracy is achieved. Experimental results show that test results of the proposed circuit having high linearity in the current range of 10-7A to 10-10A Additional current testing results using dielectric response test system which contains proposed circuit are also given, which reveals the stability of the designed micro-current measurement device.

Ephedra-cinnamomi, composed of ephedra (stems of Ephedra sinica) and cinnamomi (twig of Cinnamomum cassia), can attenuate the symptoms of colds by inducing sweat and relieving cough, asthma, headache, and arthralgia. The study was aimed to investigate the anti-inflammatory activity of the prescription of ephedra-cinnamomi on the cerebral ischemia-induced neuroinflammation. Ephedra-cinnamomi down-regulating the inflammatory mediators including Tumor Necrosis Factor-α (TNF-α, Interleukins (IL) IL-6. Moreover, Ephedra-cinnamomi significantly induced reduction of TLR4 and NF-κB mRNA level, consistent with the RT-qPCR results, Ephedra-cinnamomi decreased TLR4 expression and phosphorylated NF-κB p65 in concentration-dependent manners. The results revealed that Ephedra-cinnamomi may effectively inhibit ischemia-induced neuroinflammation through TLR4/NF-κB pathway. We have provided evidence indicating that Ephedra-cinnamomi induces suppression of inflammatory mediators and possesses therapeutic effect on neuroinflammation.

A planar millimeter-wave 2-D beam-scanning multibeam array antenna fed by compact 16-way beam-forming network (BFN) in multilayered substrate integrated waveguide (SIW) technology is addressed. The BFN is formed by connecting two stacks of sub-BFNs, the E-plane sub-BFN and the H-plane sub-BFN. The H-plane sub-BFN is realized by a traditional H-plane $4 \times 4$ Butler matrix (BM). The key point of this design is to propose an E-plane $4 \times 4$ BM which realizes a planar E-plane sub-BFN. These two sets of sub-BFNs can joint directly without resorting to any connectors or connecting networks to form such a compact 16-way BFN with a reduced area of merely $3\lambda \times 12\lambda $ . After that, to be compatible with the proposed BFN, a ladder-type $4 \times 4$ slot antenna array is employed, which is comprised of four linear $1 \times 4$ slot antenna arrays. Different from traditional array, the four subarrays are distributed in separate layers for the purpose of jointing to the BFN more conveniently. Transition network are also required to connect the BFN with the antenna array. Finally, a compact 2-D scanning multibeam array antenna based on the planar SIW BFN are fabricated and measured, which would be an attractive candidate for 5G application.

To investigate the antipyretic mechanism of Herba Ephedrae (Eph)-Ramulus Cinnamomi (RC) herb pair on yeast-induced pyrexia in rats. Totally 30 qualified male SD rats were randomly assigned to the normal control (NC) group, the pyrexia model (model) group, the Eph, RC and Eph-RC treatment groups by a random digital table, 6 rats in each group. Each rat received a 20% aqueous suspension of yeast (10 mL/kg) except the NC group. The 3 treatment groups were administered 8.1, 5.4 and 13.5 g/kg Eph, RC and Eph-RC respectively at 5 and 12 h after yeast injection, the NC group and the model groups were administered equal volume of distilled water. Rectal temperatures were measured at 0, 6, 8, 10, 12, 15, 18, 24 and 30 h and urine was collected prior to yeast injection and at 6, 10, 18, 24, 30, and 36 h after yeast injection. Then urine metabolomic profiling by gas chromatography tandem mass spectrometry, coupled with multivariate statistical analysis and pattern recognition techniques were used to explore the antipyretic effects of Eph-RC. Partial least squares discriminate analysis was used to analyze the metabolomics dataset including classification and regression in metabolomics plot profiling. Compared with the NC group, rectal temperatures were significantly higher in the model group (P

The wet etchings of as-grown and thermal annealed ZnO films were carried out by using NH 4 Cl and acidic etchants respectively. The lateral profiles and side faces of the etched ZnO samples were exhibited by profiler and SEM measurements. NH 4 Cl etchant can avoid W-like lateral profile and eave-like slope at the side face of the etched ZnO patterns for both as-grown and post-annealed ZnO samples. The etching rate has been compared between NH 4 Cl etchant and acidic etchants for both as-grown and post-annealed ZnO samples. NH 4 Cl etchant can maintain slower etching rate with higher NH 4 Cl concentration. The thermal annealing procedure can be helpful to achieving uniform etching surface, and the etching rates of the annealed ZnO samples are even slower, which can be explained by the better crystallinity and lower density of oxygen vacancy.