Experimental Research on High-strength Inorganic Anchoring Material

A new type of inorganic anchoring material is developed as a substitution for anchoring adhesive to overcome some imperfections in the process of planting reinforcing steel bar.The mix proportion of the anchoring material is determined by experiments.The compressive strength,adhesive force to concrete,volume stability and anchoring force with steel bar are studied.The early strength of the anchoring inorganic material is quite high: for 1d up to 38.5MPa and 3d up to 60MPa.It is a good adhesive to concrete and the adhesive strength of 28d is about 2MPa.The anchoring material will have tiny volume expansion with the age,which is beneficial to enhancing the anchoring force.The essential component of the inorganic anchoring material is cement-based material,so some defects of the organic macromolecular material can be avoided,such as poor stability and requirement for vigorous construction conditions.Its characteristics in early strength,adhesive force to concrete and volume expansion can satisfy the requirement of the construction to the planting reinforcing steel bar and the loading force,thus it can be used as a substituting material for anchoring adhesive.     

Determination to Weighting Coefficient of Combination Forecast Based on Rough Set Theory

The problem of determination to weighting coefficient is a key and difficulty for combination forecast. A method of determining weighting coefficient based on rough set theory is showed in this paper. Determining weighting coefficient is translated into estimating significance of attributes among rough set. A relation data model about combination forecast is established. Knowledge systems are built through making attribute value into eigenvalue. Under data moving, the weighting coefficients of a combination forecast model are computed by analyzing the dependence and significance of forecasting method for the predicted object. The proposed approach overcomes the subjectivity of traditional determination to weighting coefficient, avoids computing linear or nonlinear extremum problem and makes combination forecast more objective. The validity of the proposed approach is verified with a case.     

Influence of MUD on the System Capability of CDMA

In CDMA communication system, the relativities between users result in Multiple Access Interference (MAI). With the increase of users, MAI becomes the main jam of broadband CDMA communication system. Multi-User Detection (MUD) is the most important technology of anti-jamming in the broadband CDMA communication system, which can eliminates MAI effectively by using the information of all user signals to detection single. This paper analyze the expression of system capability without MUD and with MUD, and puts forward the way to increase system capability by using MUD. Then the influence of MUD on CDMA system capability is discussed by MATLAB emulation. Basing analysis and emulation, the conclusion is got: the higher the MUD efficiency, the better the improvement of CDMA system capability; under the same MUD efficiency, the lower data rate, the smaller inter-cell interference, the lower the ratio of bit energy to power spectrum, the better the improvement of CDMA system capability.     

窄缝式挑坎体型及动水压强特性分

通过窄缝式挑坎的体型布置、动水压强特性等资料的总结和分析研究，对窄缝式挑坎的体型布置和反弧收宿段动水压强的计算方法进行探讨，将反弧收缩段的窄缝式挑坎动水压强分为两部分：一为反弧段曲率边界引起的离心惯性力，二为窄缝挑坎水流横向收缩产生的附加动水压强。通过分析研究和水力模型试验，提出了窄缝式挑坎最大动水压强的估算式。研究成果可供工程设计参考。     

根系生长与土壤物理性状之间的关系

根系生长在土壤之中,土壤物理条件的改变会对根系生长产生直接或间接的影响.为此,通过分析土壤主要物理条件,对土壤物理环境与作物生长之间的关系进行了评述,并对目前研究中存在的不足及今后需深入的研究领域提出了建议.     

沼液与化肥和有机肥配施对桃产量和品质的效应

采用田间试验研究了沼液在不同施肥处理中对桃产量和品质的影响。结果表明,与常规施肥相比,仅在常规施肥基础上增施沼液(T2处理)不能提高桃产量,沼液仅与钾肥配施(T3处理)还会降低桃产量,沼液配施磷钾(T4处理)或配施油饼(T5处理)能提高桃产量,且配施油饼的增产效果最显著,增产幅度最大。T4和T5处理均能增加桃果实中的Vc含量。各处理与常规施肥相比,桃果实中的还原糖含量均有所降低,以T5处理中还原糖的含量最低,仅为常规处理的48.48%。除T5处理中桃果实的有机酸含量略有增加外(1.77%),其他处理的有机酸含量都有所降低(5.42%～9.22%)。各处理的糖/酸与常规施肥相比均大幅度下降,降幅为21.42%～53.36%。     

渠道滤透式刚柔耦合衬护结构经济特性分析

采用工程实例分析了渠道滤透式刚柔耦合衬护结构的工程造价、维护费用,并与其它衬砌形式进行了对比分析。结果表明:在高地下水位区,渠道滤透式刚柔耦合衬护结构在工程造价、使用寿命、管理维护费用等经济特性上明显优于其它衬护形式,技术可靠,经济合理,具有推广应用价值。     

Construction of mouse ESC line stably expressing Pdx1 by Tet-On system

AIM To construct the mouse embryonic stem cell （ESC） line with stable pancreatic and duodenal homeobox 1 （Pdx1） expression by Tet-On system, which may lay a foundation for further research on the differentiation of Pdx1⁺ definitive endoderm cells into pancreatic cells. METHODS The Pdx1-overexpressing lentiviral vector with green fluorescent protein marker and puromycin resistance was constructed by Tet-On system and was used to infect the mouse ESC. The cells were divided into 3 groups： blank control group （ESC group）, empty lentivirus control group （PDX1^- ESC group） and Pdx1 lentivirus transfection group （PDX1⁺ ESC group）. Flow cytometry was used to detect the transfected cells after screening by doxycycline （DOX）. The function of Tet-On system and the expression of Pdx1 gene were detected. The transfected cells in PDX1^- ESC group and PDX1⁺ ESC group were sorted by flow cytometry, and constructed ESC line with stable expression of Pdx1 and negative control ESC line were verified. RESULTS （1） The positive rates of transfected cells in PDX1^- ESC group and PDX1⁺ ESC group were 90.72% and 94.01% after screening by DOX, respectively. The positive rates of transfected cells in PDX1^- ESC group and PDX1⁺ ESC group was 97.84% and 98.13% after sorting by flow cytometry, respectively. （2） With DOX, green fluorescence was observed in PDX1^- ESC group and PDX1⁺ ESC group. The mRNA and protein expression of Pdx1 was significantly increased in PDX1⁺ ESC group （P<0.05）. Without DOX, no green fluorescence was observed in the cells of the 3 groups, and no significant difference in the mRNA and protein expression of Pdx1 was observed （P>0.05）. （3） After 3 months of cryopreservation, the cell lines still survived in resuscitation culture and were regulated by DOX. CONCLUSION Using Tet-On system, the mouse ESC line with inducible Pdx1 expression were successfully established and could be used as an effective cell model to research the differentiation of Pdx1⁺ definitive endoderm cells into pancreatic cells.     

Expression of cathepsin C and tumor necrosis factor-α in human coronary artery and their relationships with coronary heart disease

AIM To explore the possible mechanism of cathepsin C （CTSC） and tumor necrosis factor-α （TNF-α） in coronary heart disease （CHD） by detecting the protein expression of CTSC and TNF-α in human coronary artery tissue. METHODS The coronary artery tissues from 52 cases of CHD and 25 cases of accidental death without any heart disease in the Forensic Judicial Expertise Center of Guizhou Medical University from October 2018 to December 2019 were collected as CHD group and control group, respectively. The coronary artery stenosis and intimal plaque formation were examined by histopathology, the protein expression of CTSC and TNF-α was determined by Western blot, and the intracellular expression of CTSC and TNF-α was analyzed by immunohistochemical staining. RESULTS The results of HE staining showed that the intima of coronary artery in control group was smooth, and no thickening or stenosis was observed. In CHD group, the intima thickened irregularly, atherosclerotic plaques formed, the intima became thinner and the lumen showed eccentric stenosis in varying degrees （P<0.05）. The results of Western blot showed that the expression of CTSC and TNF-α in CHD group was significantly higher than that in control group （P<0.05）. Immunohistochemical staining showed that both CTSC and TNF-α were expressed in the cytoplasm of foam cells, and their positive expression was significantly higher than that in control group （P<0.05）. The results of Pearson moment correlation analysis showed that there was positive correlation between the expression of CTSC and TNF-α in CHD （r²=0.743, P<0.05）. CONCLUSION The up-regulated expression of CTSC in coronary artery tissue may promote the expression of TNF-α and affect the occurrence and development of CHD.