Carbon Dioxide, Methane, and Nitrous Oxide Emissions from a Rice-Wheat Rotation as Affected by Crop Residue Incorporation and Temperature

Field measurements were made from June 2001 to May 2002 to evaluate the e?ect of crop residue application and temperature on CO2, CH4, and N2O emissions within an entire rice-wheat rotation season. Rapeseed cake and wheat straw were incorporated into the soil at a rate of 2.25 t hm?2 when the rice crop was transplanted in June 2001. Compared with the control, the incorporation of rapeseed cake enhanced the emissions of CO2, CH4, and N2O in the rice-growing season by 12.3%, 252.3%, and 17.5%, respectively, while no further e?ect was held on the emissions of CO2 and N2O in the following wheat- growing season. The incorporation of wheat straw enhanced the emissions of CO2 and CH4 by 7.1% and 249.6%, respectively, but reduced the N2O emission by 18.8% in the rice-growing season. Signi?cant reductions of 17.8% for the CO2 and of 12.9% for the N2O emission were observed in the following wheat- growing season. A positive correlation existed between the emissions of N2O and CO2 (R2 = 0.445,n = 73,p < 0.001) from the rice-growing season when N2O was emitted. A trade-o? relationship between the emissions of CH4 and N2O was found in the rice-growing season. The CH4 emission was signi?cantly correlated with the CO2 emission for the period from rice transplantation to ?eld drainage, but not for the entire rice-growing season. In addition, air temperature was found to regulate the CO2 emissions from the non-waterlogged period over the entire rice-wheat rotation season and the N2O emissions from the non- waterlogged period of the rice-growing season, which can be quantitatively described by an exponential function. The temperature coe?cient (Q10) was then evaluated to be 2.3±0.2 for the CO2 emission and 3.9±0.4 for the N2O emission, respectively.

RELATIONSHIP BETWEEN THE EXPRESSIONS OF LMP1 AND ECADHERIN/β-CATENIN IN NASOPHARYNGEAL CARCINOMA

Objective: To compare the expression of Epstein-Barr virus encoded LMP1 and E-cadherin/β-catenin in primary and metastatic nasopharyngeal carcinoma (NPC) for the purpose of understanding their relationship. Methods: Twenty-two pairs of biopsies taken from the nasopharynx and cervical lymph node(s) of the same patient with nasopharyngeal carcinoma were collected. The expression of LMP1, E-cadherin and β-catenin was observed on immunostained slides using LSAB method. Results: The expression rate of LMP1 in the 22 metastatic tumors (86.36%, 19/22) was significantly higher than that in the 22 primary growths (68.18%, 15/22), P<0.05. The mean expression percentages of E-cadherin and β-catenin in metastatic tumors (50.11%±22.53% and 66.36±21.05%, respectively) were significantly lower than those in primary growths (71.52±24.34 % and 79.40%±15.05%, respectively), P<0.05. There was a positive correlation between the expressions of E-cadherin and β-catenin either in primary growths or metastatic tumors. Conclusion: The LMP1 is more likely to be expressed in metastatic neoplastic cells of NPC than in primary carcinoma cells, and on the contrary the expression of E-cadherin/β-catenin in metastatic cells was decreased. Accordingly, the LMP1 might have the ability to downregulate the expression of E-cadherin/β-catenin, resulting in enhancement of the invasive capacity of metastatic NPC cells.

An Abnormal Reaction of N- (2,4-dinitrophenyl)-L-proline with Thionyl Chloride

N- (2,4-Dinitrophenyl)-4-amino-n-butyl aldehyde 3 was obtained with high yield of 80% when N- (2,4-dinitrophenyl)-L-proline 1 reacted with SOCl2 at room temperature. However, the anticipated product N- (2,4-dinitrophenyl)-tetrahydropyrrolyl-2- (4-methylthiophenyl) ketone 2 did not be produced. The mechanism was discussed in this article.