Batch and fed-batch production of butyric acid by Clostridium butyricum ZJUCB

The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, this study then compared batch and fed-batch fermentation of butyric acid production at pH 6.5. Maximum value (16.74 g/L) of butyric acid concentration was obtained in fed-batch fermentation compared to 12.25 g/L in batch fermentation. It was concluded that culti- vation under fed-batch fermentation mode could enhance butyric acid production significantly (P<0.01) by C. butyricum ZJUCB.

Studies on the role of microtubules in myofibrillogenesis

Co-localization of mierotubule (MT) and muscle myosin (MHO) myofibril immunofluoresoence in developing myotubes of chicken' skeletal muscle cultures was observed by using double staining of tubulin and MHO indirect immunofluorescence. 12-o-tetradeeanoyl-phorbol-13-acetate (TPA) selectively and reversibly blocks mycfibrillogenesis and alters the morphology of myotubes into myosacs where MTs are present in radiating pattern,when the arrested myogenic cells recover and start myofibrillogenesis after released from TPA, prior to the emergence of myofibrils, the pre-existing MTs become bipolarly aligned ooincidently with the tubular restoration of cell shape. Single nascent myofibrils overlapping with MTs extend into the base of growth tips where MTs go farther to the end of the tips. That MT might act as scaffold in guiding the bipolar elongation of the growing myofibrils was suggested. Taxol and ooloemid disturbed MT polymerization and disposition, and interfered with the normal spatial assembly of myofibrils in developing myotubes.

^5He Emission in Neutron-Induced ^10B Reactions

In n ＋^10B reactions, ^5He cluster emission has been discussed with the updated level scheme and the new optical model parameters. In this paper the reaction channels related to ^5He emission are listed in detail. By using the new reaction model for light nuclei, the double-differential cross sections of total outgoing neutrons for n ＋ ^10 B reactions at En= 14.2 MeV have been calculated, and the results agree fairly well with the measurements. Particularly, in the energy-angular spectra the contribution from the 5He-emission to the total outgoing neutron double-differential cross sections has also been analyzed, and the partial energy-angular spectra of 60° at En= 14.2 MeV have been given. The calculated results indicate that once the 5He emission is taken into account, the fitting with the double-differential measurements of total outgoing neutrons at the low energy region could be improved. Therefore, to consider the ^5He emission properly in the reaction processes of light nuclei is necessary.

Therapeutic and Immunomodulatory Effects of Raw Maize ＂OGI＂ on Rats Infected with Escherichia coil 0157：H7

Escherichia coli O157：H7 is known to cause food borne illness globally. Treatment of infections caused by this organism is difficult because the administration of antibiotics might precipitate kidney complications; therefore there is the need to search for alternative therapy. In this study, the therapeutic and immunomodulatory effects of raw maize ＂ogi＂ was investigated on rats infected with Escherichia coli 0157：H7. Infected rats treated with maize ＂ogi＂ slurry 1.0 mL once or twice daily and maize ＂ogi＂ liquor, 1.0 mL twice daily recovered 72 h while those that were treated with less than 1.0 mL recovered by 96 h. Without treatment with ＂ogi＂ however, the rats started recovering by 120 h. The treatment caused the white blood cells which had already gone up as a result of the infection to reduce significantly （P 〈 0.05） by 24 h of administration of raw fermented maize ＂ogi＂ components to the infected rats. It also caused a significant decrease in the lymphocyte counts of the infected and treated rats by 24 h. On the other hand, there was an increase in the neutrophil count irrespective of the different volumes and different components of raw ＂ogi＂ used by 24 h but by the 72 h of treatment, it started to decrease and by 120 h reduced to normal levels. Since the administration of raw maize ＂ogi＂ either slurry or liquor caused the duration of infection in rats infected with Escherichia coli 0157：H7 to reduce from 120 h to 72 h, it is therefore suggested that people having diarrhoea caused by this organism could drink fermented raw maize ＂ogi＂ slurry or liquor to treat the infection.

微电极阵列对癫痫灶定位的作用

微电极阵列是在标准电极基础上发展而来的新的电生理技术,其电极直径及相互间距均在一毫米以下,能在更小脑组织空间内探测到标准电极无法探测的异常放电。通过对动物模型进行微电极阵列植入,探测到一些新的癫痫放电模式。对癫痫患者植入,探测到的微型脑电图在空间分布和时间分布上不同于传统的颅内脑电图。这些新的电生理现象能在更加细小的空间内对癫痫灶进行定位,提高癫痫灶定位的准确性。

Formation mechanism of subtrenches on cone-shaped patterned sapphire substrate

In this paper, the cone-shaped patterned sapphire substrates (PSS) were etched by an inductively couple plasma with BCl 3 as the reacting gas. The influence of the operating pressure and the RF bias power on subtrenches of the cone-shaped PSS and the formation mechanism of subtrenches were investigated. The profiles of patterns were characterized by FESEM (field emission scanning electron microscope). It showed that the subtrench size varied with the operating pressure and the RF bias power. As the operating pressure increased from 0.2 Pa to 0.9 Pa, the subtrenches changed from narrow and deep to wide and shallow; then to narrower and shallower. When the RF bias power varied from 200 W to 600 W, the subtrenches gradually became noticeable. The FESEM results also indicated that the subtrenches were formed due to the ion scattering effect which was caused by tapered sidewalls and charges accumulation. It is discovered that the scattering effect is closely related with the operating pressure and RF bias power.