Semen Ziziphus jujube (SZJ), the seeds of Ziziphus jujuba Mill. var. spinosa, is a kind of traditional Chinese medicine used for its action on insomnia. In order to analyze the effective component, we investigated and compared the sedative and hypnotic effects of three kinds of compounds, flavonoids, saponins, and polysaccharides. Flavonoids, saponins, and polysaccharides were extracted from SZJ and orally administered to mice separately at 17 g kg(-1) per day for certain days before animal tests. Spontaneous motility and coordinated movement tests were used to observe the effects of the three kinds of compounds on the mouse behavior, and sodium barbital-induced sleeping time of mouse were tested to analyze the effects of the three kinds of compounds on the sleep of mouse. Results show that flavonoids and saponins caused a significant reduction of walking time and coordinated movement ability of mouse, significantly prolonged its sleeping time at 40 mg kg(-1), ip, subthreshold dose and increased the sleeping number of animals at 50 mg kg(-1), ip, superthreshold dose induced by coeliac injection of sodium barbital. Polysaccharides did not show any significance in all animal tests. Comparative analysis showed that saponins had a more effective sedative and hypnotic function than that of flavonoids, polysaccharides did not show a sedative and hypnotic effect.

Ab initio calculations are used to provide information on H(3)N...XY...HF triads (X, Y=F, Cl, Br) each having a halogen bond and a hydrogen bond. The investigated triads include H(3)N...Br(2)-HF, H(3)N...Cl(2)...HF, H(3)N...BrCl...HF, H(3)N...BrF...HF, and H(3)N...ClF...HF. To understand the properties of the systems better, the corresponding dyads are also investigated. Molecular geometries, binding energies, and infrared spectra of monomers, dyads, and triads are studied at the MP2 level of theory with the 6-311++G(d,p) basis set. Because the primary aim of this study is to examine cooperative effects, particular attention is given to parameters such as cooperative energies, many-body interaction energies, and cooperativity factors. The cooperative energy ranges from -1.45 to -4.64 kcal mol(-1), the three-body interaction energy from -2.17 to -6.71 kcal mol(-1), and the cooperativity factor from 1.27 to 4.35. These results indicate significant cooperativity between the halogen and hydrogen bonds in these complexes. This cooperativity is much greater than that between hydrogen bonds. The effect of a halogen bond on a hydrogen bond is more pronounced than that of a hydrogen bond on a halogen bond.

Citrus aurantium L. var. amara Engl is a member of genus Citrus (Rutaceae) and has been used in Chinese medicine with the effectiveness of digestant and expectorant. Ultrasonic-assisted extraction process for maximum flavonoids from the flower of Citrus aurantium L. var. amara Engl was investigated by response surface methodology. Through single factor experiment, ranges of the main variables (including ethanol concentration, solid/liquid ratio, extraction time and temperature) affecting the extraction yield of flavonoids were confirmed. Box-Behnken central composite design consisting of 24 experimental runs and 5 replicates at zero point was then applied and a regress model was obtained to predict the optimal extraction yield. The ANOVA indicated that the regression equation fits very well with the actual situation, reflecting the relationship between the extraction yield of flavonoids and extraction conditions. The optimal conditions were as follows: extraction temperature 72.11 degrees C, time 51.89 min, ethanol concentration 51.19% and liquid/solid ratio of 40:10. Under the optimal conditions, the maximum response value of yield (1.88%) was consistent with the experimental value (1.87%), indicating the feasibility and validation of response surface methodology in optimizing the extraction of flavonoids from the flower of Citrus aurantium L. var. amara Engl.

A 45-m-long high-temperature superconducting (HTS) Maglev ring test line, named as "Super-Maglev", has been successfully developed in Chengdu, China in February, 2013, 12 years after the birth of the first man-loading HTS maglev test vehicle. The maglev vehicle (2.2 m in length, 1.1 m in width) is designed for one passenger with a levitation height of 10-20 mm; the permanent magnet guideway (PMG) (45 m in length, 0.77 m of track gauge) is a racetrack shape with a curve radius of 6 m; the driving is accomplished by a linear induction motor with a maximum running speed of 50 km/h. The linear motor is composed of four sub-motors installed at one straight section in the middle of the double PMGs and the total length is 3 m. Thissecond-generation HTS Maglev vehicle system is highlighted by the cost-performance and the wireless multi-parameter onboard monitoring function. The current same-level load capability has been achieved over a small-section low-cost PMG whose cross sectional area is only 3000 mm 2 . On the vehicle, parameters of levitation weight, levitation height, running speed, acceleration, lateral offset, online position and total running distance of the vehicle are real-time monitored and displayed on the onboard tablet computer. The system component and test data are reported in detail in the paper.

Sperm cells of seed plants have lost their motility and are transported by the vegetative pollen tube cell for fertilization, but the extent to which they regulate their own transportation is a long-standing debate. Here we show that Arabidopsis lacking two bHLH transcription factors produces pollen without sperm cells. This abnormal pollen mostly behaves like the wild type and demonstrates that sperm cells are dispensable for normal pollen tube development.

No abstract

No abstract

No abstract