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A new carboline alkaloid, Trifiline D (1) and a new degraded diterpenoid, Trigoxyphin X (4) were isolated from the roots and stems of Trigonostemonlii. Their structures were elucidated by extensive spectroscopic analyses including 1D- and 2D-NMR techniques. Compound 1 exhibited weak inhibitory activity against MCF-7, A-549, MGC-803, and COLO-205 with IC50 values ranging from 27.4 to 35.4 mu M.

A detailed understanding of microbial ecology in different supraglacial habitats is important due to the unprecedented speed of glacier retreat. Differences in bacterial diversity and community structure between glacial snow and glacial soil on the Chongce Ice Cap were assessed using 454 pyrosequencing. Based on rarefaction curves, Chao1, ACE, and Shannon indices, we found that bacterial diversity in glacial snow was lower than that in glacial soil. Principal coordinate analysis (PCoA) and heatmap analysis indicated that there were major differences in bacterial communities between glacial snow and glacial soil. Most bacteria were different between the two habitats; however, there were some common bacteria shared between glacial snow and glacial soil. Some rare or functional bacterial resources were also present in the Chongce Ice Cap. These findings provide a preliminary understanding of the shifts in bacterial diversity and communities from glacial snow to glacial soil after the melting and inflow of glacial snow into glacial soil.

To explore the source of heavy metals in lake sediments and their hazard to environment on Tibetan Plateau, China, heavy metal (Cu, Zn, Cd, Pb, Cr, Co, Ni and As) levels in surface sediments of 18 lakes were investigated. Inductively Coupled Plasma Mass Spectrometry (ICP-MS, X-7 series) was used to determine the contents of heavy metals and the concentrations of carbon and nitrogen in sediment samples were analyzed by element analyzer (Vario Max CN, Elementar, Germany). The average concentrations for Cu, Zn, Cd, Pb, Cr, Co, Ni and As were 24.61 mg x kg(-1), 70.14 mg x kg(-1), 0.26 mg x kg(-1), 25.43 mg x kg(-1), 74.12 mg x kg(-1), 7.93 mg x kg(-1), 33.85 mg x kg(-1), 77.69 mg x kg(-1). It was found that heavy-metal concentrations in Tibet sediments were higher than those in Antarctic, but lower than those in the regions affected by anthropogenic activities. The contents of Cu, Zn, Pb, Cr and Co in the samples were lower than the background values of Tibet. Correlation analysis and principal components analysis (PCA) were used to analyze the origins of heavy metals. The result showed that Cu, Zn, Cd, Pb, Co, Ni and As came from soil in drainage basin and atmospheric deposition. Cr was mainly affected by human activities. Assessment on ecological risk of heavy metals was carried out using Hakanson's method and cluster analysis (CA). Assessment on ecological risk indicated that Pumoyum Co, Longmo Co and Bangong Co were at low risks, Bieruoze Co was at high ecological risk level and the other lakes were at different risk levels.

As to the optimum of extremum value controlled plant, if the transfer function of its linear part is only with the high order dynamic elements, the optimum of extremum value control system could be dynamically pre-estimated by using the method based on correlation identification we presented, the pre-estimating method has the estimate speed quickly, anti-jamming ability strong, accurate, highly effective and so on the merits. However, if the controlled plant is simultaneously with high order dynamic elements and a large time delay element, the method could not be used directly to pre-estimate dynamically the optimum of the extremum value control system. A new improved pre-estimating method is presented so as to resolve the problem above. After we have in detail analyzed the derivation process of the pre-estimating method we presented, Fully taking into account the effects of large time-delay element, a number of conditions have been improved, the algorithm based on correlation identification has been extended, the optimum of extremum value control system with a large time delay element is well resolved by the extended algorithm.

Design and implementation of Automatic Schematics Verification Platform based on open EDA (Electronic Design Automation) tools has been discussed. This platform adopts client/server pattern and provides an environment of design Verification and sharing data for designers separately, and at the same time, this platform has strong transplantable ability because of it’s strong cohesion and weak coupling with the open EDA tool, therefore we can transplant this platform to other open EDA tools expediently.

To analyze the inhibition to SSN, we use the design and emulation tools from Ansoft Co., which are used in the optimization design on PDS, integrated with particular circuit designs. Firstly, the traditional means of adding Decoupling Capacitor is adopted to inspect and verify that increased decoupling capacitors will help to increase high frequency response. Secondly, we introduce a high impedance electromagnetic surface texture, which can be applied to decrease SSN. Lastly, we support that EBG is better than traditional adding decoupling capacitor.

The relationship between the length of the objects reflections on the water surface and the following factors including the spacing of objects and people，height of objects，observers’ height and the size of wave are discussed. According to the law of light reflection, a parametric equation is established among them. Secondly, the numerical solutions of the equation can obtained by MATLAB and draw the virtual image of the material point in the water. Besides, the objects reflection on the water surface with slight wave was simulated. Finally, a detailed qualitatively analysis for the relevant factors which affect the length of reflection are made and explains the physical phenomenon successfully.

Different encoding scheme and method for process description of state machine are analyzed in detail, and the advantages and disadvantages of each are pointed out. The general state machine design method is given by a specific example program, according to the actual need, designers can choose different encoding scheme and method for process description to design.

As the optimum of extremum value control system drifts faster it may make bigger error for pre-estimating statically the optimum, it is particularly remarkable if the transfer function of the linear part is with a high order dynamic element. In this paper, a method based on LS(least squares) is presented to pre-estimate dynamically the optimum of extremum value control system. The linear part of controlled plant could be approximated by a cascade of 1st order dynamic element and a pure time delay element as the controlled model is simplified it is successfully resolved for pre-estimating dynamically the optimum of extremum value control system with a high order element by LS.

This paper investigates a new method, the Levenberg-Marquardt method, to calculate the phase equilibria of the Al-Cu-Mg ternary alloys. The Levenberg-Marquardt method is the best algorithm to obtain the least-square solution of non-linear equations. Its application to ternary Al-Cu-Mg system is executed in detail in this paper. The calculated phase equilibria agrees well with the experimental results. Furthermore, the Levenberg-Marquardt method is not sensitive to the initial values.

Ferroelectric BaTiO3/polyvinylidene fluoride (BaTiO3/PVDF) composites were prepared by a coating technique. It was observed that BaTiO3powders prepared with different thermal treatment temperatures affected dielectric performances of the composites. The polymer with fine BaTiO3powder exhibited a lower dielectric loss than that with coarse powder. Fourier transform infrared spectrum was carried out to investigate the vibration of chemical bonds. The relationship between the dielectric property and intercoupling between F-ion and oxygen octahedron was discussed.

Objective To investigate the neuroprotective effect of ginsenoside Rd (GSRd) on glutamate-induced spinal cord motoneuron injury in vitro. Methods The spinal cord motoneurons obtained from embryonic 15 days SD rats were cultured for 6 days, and then randomly assigned into four groups as follows. Control: no treatment; Glu: glutamate 300μmol/L was added to the spinal cord neurons; GSRd+Glu: the spinal cord neurons was pretreated with 10μmol/L GSRd for 30min, and then glutamate 300μmol/L was added to the spinal cord neurons; Vehicle+Glu: the spinal cord neurons was pretreated with propylene glycol at the same volume as that used for GSRd, and then glutamate 300μmol/L was added to the spinal cord neurons. After the cultures were incubated with glutamate for 24h, the motor neurons were counted and observed for morphology and growth under phase-contrast microscope; the neuron viability was determined by methyl thiazolyl terazolium assay (MTT) assay; the activity of lactate dehydrogenase (LDH) leaked into the culture medium also was measured. Results There were less living spinal motor neurons and neuronal processes in Glu group than in GSRd+Glu group. The nervous cells were severely damaged in Glu group, while the dead cells were very few in GSRd+Glu group. The neuronal morphology in Vehicle+Glu group was similar to that in Glu group. The survival rates of spinal motor neurons were 22.7%±2.3% and 23.6%±2.1% in Glu group and Vehicle+Glu group respectively and significantly lower than those in control group (100%±0%, P < 0.05) and GSRd+Glu group (58.6%±2.3%, P < 0.05), while there was no statistical difference between Glu group and Vehicle+Glu group and between control and GSRd+Glu groups (P>0.05). The LDH activity in the culture supernatant was 142.50±3.55 and 139.20±2.75U/L respectively in Glu and Vehicle+Glu, which were significantly higher than those in control group (42.3±3.6U/L, P < 0.05) and GSRd+Glu (84.2±2.5U/L, P < 0.05), but there wasn't significant difference between Glu and Vehivle+Glu groups and between control and GSRd+Glu groups (P>0.05). Conclusion GSRd has neuroprotective effect on spinal cord motoneurons from glutamate-induced injury in vitro.

To observe the impacts on the muscle strength in the patients of stroke-induced acroparalysis treated with Xunjingcuiqi needling technique.One hundred patients were randomized into a Xunjingcuiqi group and a routine acupuncture group, 50 cases in each group. In the routine acupuncture group, the routine acupuncture technique was adopted at the main acupoints, such as Shangxing (GV 23), Baihui (GV 20), Dicang (ST 4), Quchi (LI 11), Huantiao (GB 30) and Zusanli (ST 36), etc. In Xunjingcuiqi group, on the basis of the routine acupuncture technique, Xunjingcuiqi needling technique (pricking technique was quickly applied with the filiform needle along the running course of meridian to promote the conduction of meridian qi) was added. For the patients being hard to feel the needling sensation and with the muscle strength of 0 to 1 degree, Dongzhencuiqi technique was supplemented at shu-stream points of yang meridians (after qi arrival, the needling manipulation with limb movement was given to promote the conduction of meridian qi). The treatment was given once every day in the two groups. Ten treatments made one session. Three sessions of treatment were required. At the end of each session treatment, the muscle strength and clinical efficacy were assessed.In the 1st, 2nd and 3rd sessions of treatment, 20, 24 and 36 cases achieved the 3 to 5 degrees muscle strength in Xunjingcuiqi group, respectively; and 6, 10 and 15 cases achieved the 3 to 5 degrees muscle strength in the routine acupuncture group. The differences were significant statistically in comparison of the two groups (P0.01, P0.05). The markably effective rates were 60.0% (30/50), 64.0% (32/50) and 70.0% (35/50) after the 1st, 2nd and 3rd sessions of treatment in Xunjingcuiqi group, respectively; and those were 38.0% (19/50), 44.0% (22/50) and 46.0% (23/50) in the routine acupuncture group, respectively. The differences were significant in the 1st and 3rd sessions of treatment between the two groups (both P0.05).Xunjingcuiqi needling technique combined with routine acupuncture achieves the apparent superior efficacy on acroparalysis induced by ischemic stroke as compared with the simple routine acupuncture. Xunjingcuiqi needling technique obviously improves muscle strength and shortens the duration of sickness.

(Na0.535K0.48) NbO3 ceramics doped with Bi2O3•Fe2O3 are prepared by a ceramic process. The effect of Bi3+ and Fe3+ on microstructure and electrical properties of ceramics is investigated. X-ray diffraction shows that the structure of the material is perovskite. The conductivity of ceramics increases with the doping content. UV-Visual absorption spectrum is affected by doping Bi3+ and Fe3+. The mechanism of conductivity is discussed with respect to energy of band-gap in the system.

Rocuronium and vecuronium, two non-depolarizing neuromuscular blockers, have been widely used in surgery procedures. However, their electrophysiological properties need to be more widely explored. We examined the effects of rocuronium and vecuronium on initial rundown of endplate potential amplitudes in the non-uniform stretched muscle preparation of the rat isolated phrenic nerve diaphragm. More specifically, the endplate potentials were recorded with one microelectrode from a single endplate. The effects of rocuronium or vecuronium each at 4 concentrations (0.5 ×, l ×, 2 ×, 4 × EC95; EC95 = concentration of the drug required to produce the inhibitory effect by 95%) on the amplitude of endplate potentials and its rundown were observed. Treatment of the isolated rat phrenic nerve-diaphragm preparation with rocuronium (2.5–20 μg/ml) or vecuronium (0.5–4 μg/ml) decreased the amplitude of endplate potentials and inhibited its rundown in a concentration-dependent manner. At the concentration (2.5 μg/ml for rocuronium and 0.5 μg/ml for vecuronium) that did not alter the endplate potential amplitude, the onset of reduced endplate potential rundown was 3 and 5 min after administration of rocuronium or vecuronium, respectively. The results suggest that rocuronium and vecuronium block the neuromuscular junction presynaptically and that rocuronium does it faster than vecuronium.

The power/ground plane Segmentation suppress the simultaneous switching noise by cutting off the path of SSN. A power/ground Segmentation plane model is established and simulated by software HFSS10.0 to analyze the power/ground plane segmentation current return paths. The simulation results that the slotted plane forced return current to flow back from a distance, and circuit size increases, leading to a potential threat of electromagnetic interference.