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According to the classification principle of field sources, the geoelectric field E is composed of the spontaneous field ESP and telluric field ET. The ESP originates from the physical and chemical actions of underground media. Its change and stability have usually obvious characteristics of local sites. The ET originates from the space current system and tidal forces, and shows the nature of broad areas in diurnal variation waveforms and spectral characteristics. In respect of the microscopic mechanism of their formations, the ESP and ET can have partly same processes of mechanisms. In 2008–2013, in the vicinity of the north-south seismic zone in China mainland, the data of representative 13 geoelectric field observatories suggest that the ESP of most sites do not exhibit clear annual variation waveforms, and their stabilities depend on regions, sites, orientation, tectonic activities and other factors. In these areas, the variation of ESP showed some common phenomena like relatively steady rises and falls, rapid jumps, sudden jumps and so forth. In the vicinity of major fault and local areas, the trend turning points of big variations often show the features of temporal synchronization and quasi-synchronization. The data stability may be similar at the same period of time, while its variation forms are usually irrelevant for site factors. During the more steady phase of the ESP, the preferred orientation α of crack water seepage calculated by the application of spectral features of tidal geoelectric field tends to be in a relatively stable state; during extreme fluctuations of the ESP, the α often experiences significant changes. The α calculated on a daily basis according to the spectral characteristics of the tidal geoelectric field may reveal the daily variation information of fissures, crack water seepage, principal compressive stress of the site, which thus can help analyze the process of microscopic mechanism of macro changes of the ESP and ET.

This paper studied the time and frequency characteristics of the geo-electric field diurnal variation along two longitude chains and two latitude chains in China mainland, using the data of geo-electric field observed at 37 stations along the chains. The following significant results are obtained. The diurnal variation at most stations appears as semi-diurnal waves twice a day, near before and after the noon; in descending order of the FFT amplitude spectrums, the main periods of the diurnal variation are 12.4 h/12 h, 8 h, 24 h, etc., which are in accordance with the periods of the tidal harmonic components; the diurnal variation changes with latitude as the wave crest-to-trough amplitude gradually becomes bigger/smaller with reduced/increased latitude of the station, and also varies with longitude as the phase difference agrees with the local-time difference between the stations along the same latitude. Furthermore, the amplitude of the diurnal variation is related with the Loyd season, which reduces orderly in J-, E- and D-seasons. The possible reasons which cause the main periodic components of the diurnal variation have been discussed, as a result, it is believed that the variation of the ground eddy current intensity caused by lunisolar tidal forces and the space electromagnetic activity aroused by the solar wind jointly produce the semi-diurnal period components of the geo-electric diurnal variation.

The behaviour of electrons during electron-assisted chemical vapour deposition of diamond is investigated using Monte Carlo simulation. The electron energy distribution and velocity distribution are obtained over a wide range of reduced field E/N (the ratio of the electric field to gas molecule density) from 100 to 2000 in units of 1Td = 10-17Vcm2. Their effects on the diamond growth are also discussed. The main results obtained are as follows. (1) The velocity profile is asymmetric for the component parallel to the field. The velocity distribution has a peak shift in the field direction. Most electrons possess non-zero velocity parallel to the substrate. (2) The number of atomic H is a function of E/N. (3) High-quality diamond can be obtained under the condition of E/N from 50 to 800Td due to sufficient atomic H and electron bombardment.

A series of comparative studies was carried out on the genetic effects of 25 alien cytoplasms of wheat on the growth potential, heading stage, fertility, resistance against diseases, important agronomic traits and its heterosis of 125 nuclei-cytoplasmic hybrids of wheat. The results indicated that there were clearly effects of alien cytoplasms on some characteristics, but the nucleus still exerted main effect on other characteristics. The effect of interactions between nucleus and cytoplasm was comparative obvious in some combination. Consequently, when we utilize the effects of alien cytoplasms, we should pay full attention to the facts such as the characteristic to be improved, the effects of cytoplasm, nucleus, the nucleus-cytoplasm interactions on that characteristics. From the preliminary studies, we believed that the cytoplasmic types of M0, S1, Sv, D2, D and B, and the nucleo-cytoplasmic hybrids of (Ae. sharonensis)-B174, (Ae. squarrosa)-352-35 (Ae. cylindrica)-352-35, (Ae. cylindria)-E EN-1, (Ae. cylindrica)-NPFP, and (Ae. speltoides)-352-35 would have some utilization potentiality in cultivar improvement.

In China, a large-scale observation network that is comprised of a number of apparent resistivity (for short, AR) stations has been established for the purpose of earthquake (EQ) monitoring and prediction since the 1966 Ms7.2 Xingtai EQ in Hebei Province. Presently, over 70 AR stations are in observation in seismically active belts in densely populated areas and nearby some of large, medium-sized cities. The 2008 Ms8.0 Wenchuan great EQ in Sichuan province occurred in the AR station network that was located in the border area of both Sichuan and Gansu provinces. In the 1970s-1980s, more than 110 AR stations had been in observation, and in those years, several great earthquakes (EQs) occurred nearby AR stations, such as the 1976 Ms7.8 Tangshan EQ in Hebei province, the 1976 Ms7.2 SongpanPingwu EQ in Sichuan province, the 1976 Ms7.4 Longling EQ in Yunnan province, and the 1988 Ms7.6 Lancang-Gengma EQ in Yunnan Province. At an AR station, two horizontally perpendicular observation channels or three channels, more one horizontally skewed channel (a NE or NW channel, as illustrated in Fig.1a), are employed, and for each channel, an AR observation configuration with a symmetry four-electrode array is installed (Fig.1b). For most stations, the current electrode spacing AB 1000 ~ 2000m  .

Here we sought to evaluate the possibility of using Chinese Bama miniature pig skin as a suitable animal model for human skin. Morphologic features of the skin of Bama miniature pigs resemble those of human skin, including skin layer thickness, development of a superficial vascular system, structure of the dermal-epidermal interface, and extracellular matrix. The characteristics and densities of Langerhans cells, fibroblasts, vascular endothelial cells, and mast cells were similar between Bama pig and human skin. Immunohistochemistry showed that miniature pigs and humans have the same antigenic determinants of human laminin, fibronectin, filaggrin, collagen I, collagen III, collagen IV, and keratin but not CD34, ICAM1, or S100. In addition, collagen type I from Bama miniature pig skin exhibited physicochemical characteristics resembling those of human skin, in regard to HPLC chromatography, UV spectroscopy, amino-acid composition, and SDS-PAGE analysis. Given these results, we concluded that Bama miniature pigs have great potential as a human skin model and for developing dermal substitute materials in wound repair. However, we also observed some disparities between the skin of Bama miniature pigs and humans, including pigment cell distribution, sweat gland types, and others. Therefore, further studies are needed to completely evaluate the effects of these interspecies differences on the actual application of the model.