An integrative model and analysis of cell cycle in fission yeast

Cell cycle is a programmed process, during which a cell proliferates to two daughter cells. The eukaryotic or-ganisms share the same characters, such as four cycle phases G1, S, G2 and M, the evolutionally conserved cell cycle proteins and its dependent kinases, and the check-points mechanism[1,2]. Due to the different functions and the complicated interactions of these proteins involved in cell cycle, it is very difficult to understand the regulatory mechanism of cell cycle in a whole sense …     

Mathematical model of deoxidization with post stirring in a combined blowing converter

Dissolved oxygen in the steel at the terminal of the converter smelting process is the main cause for the formation of oxide inclusions, and the high terminal oxygen content worsens the steel cleanness. However, post stirring in a combined blowing converter can promote the carbon-oxygen reaction in the liquid steel and reduce the dissolved oxygen content at the terminal of the converter smelting process. Thus, the mathematical model of deoxidization in the post stirring process was obtained, and the rationality of which was further verified by industrial tests. Finally, it is concluded that the product of dissolved carbon and oxygen, i.e. w_[C]·w_[O], decreases obviously after adopting the new technique of post stirring in the combined blowing converter.     

Infiltration behavior of sintering liquid on nuclei ores during low-titanium ore sintering process

Sinter strength is dependent not only on the self-intensity of the residual rude and bonding phase but also on the bonding degree between them. The infiltration behavior of sintering liquid on nuclei ores influences the bonding degree, which ultimately determines the sinter strength. Infiltration tests were conducted using micro-sinter equipment. The infiltration area index of original liquid (IAO), infiltration volume index of secondary liquid (IVS), and sinter body bonding strength (SBS) were proposed to study the melt infiltration behavior. The results show that the IVS first increases and then decreases with increasing TiO₂ content in adhering fines, whereas the IAO exhibits the opposite behavior. Compared with the original liquid, the secondary liquid shows lower porosity, smaller pores, and more uniform distribution. The SBS increases first and then decreases with increasing IAO and TiO₂ content, and reaches a maximum when the IAO and TiO₂ contents are approximately 0.5 and 2.0wt%, respectively. The SBS first increases and then tends to be stable with increasing IVS. The TiO₂ content is suggested to be controlled to approximately 2.0wt% in low-titanium ore sintering.     

不同不育系所配杂交水稻组合在单,双株寄载条…

通过对不同不育系所配杂交水稻组合在单、双株寄载条件下的秧苗素质研究，结果表明：Ⅱ－３２Ａ所配组合的总根数、白根数、白根率和分蘖性能等指标均较优，特别是白根率高，根系活力和分蘖能力强，但繁茂性稍高。冈６４Ａ所配组合其突出特点是叶面积和苗高占优势，繁茂性好，秧田各时期的干物质积累能力较强，但根系活力稍差，白根率较低。二汕Ａ所配组合的特点是在发根力和根系活力上稍占优势，白根率较高。Ｄ汕Ａ所配组合无突出特     

超布朗运动的模拟

本文给出了超布朗运动的一种模拟方法。此方法与已有的方法有很大的不同，而且从理论上来讲，我们的方法更精确，而且无论二维或三维情况，其模拟均可在微机上实现。从而为进一步地利用Ｍｏｎｔｅ－Ｃａｒｌｏ方法进行非线性偏微分方程的模拟计算打下基础。     

具全期启动子盒的杆状病毒高效表达载体的组建与应用

通过ＰＣＲ扩增，得到苜蓿丫纹夜蛾核型多角体病毒（ＡｕｔｏｇｒａｐｈａｃａｌｉｆｏｒｎｉｃａＮｕｃｌｅａｒＰｏｌｙｈｅｄｒｏｓｉｓＶｉｒｕｓ，ＡｃＮＰＶ）具早晚期启动子元件的ｐ３５基因启动子，将其插入到杆状病毒转移载体质粒ｐＳＸＩＶＶＩ＋Ｘ３多克隆位点上游，使之与ｐＳＸＩＶＶＩ＋Ｘ３质粒中的人工合成后期启动子（ＰＳｙｎ）、多角体ＸＩＶ启动子（ＰＸＩＶ）串联构成早期、晚期、极晚期能持续启动外源基因表达的转移载体质粒ｐＳＸ３５．将ｐＳＸ３５用于组建含ＨＢｓＡｇ基因并形成多角体的重组ＴｎＮＰＶ，ＨＢ－ｓＡｇ基因的表达量显著提高，表达时间亦明显提前，从而实现了外源基因在杆状病毒表达系统的全期、高效表达．ｍＲＮＡ引物延伸试验结果显示，Ｐｐ３５在重组病毒中可产生２套转录本，分别于病毒感染的早期和晚期起始ＨＢｓＡｇ基因的表达．     

Foreign Trade Survey Data: Do They Help in Forecasting Exports and Imports?

Business survey, which starts from the microeconomic level, is a widely used short-term forecasting tool in practice. In this study, the authors examine whether foreign trade survey data collected by China’s Ministry of Commerce would provide reliable forecasts of China’s foreign trade.The research procedure is designed from three perspectives including forecast information test, turning point forecast, and out-of-sample value forecast. First, Granger causality test detects whether survey data l...     

Chemical and Genetic Diversity of Some Ligularia Species （Compositae） in Northwestern Yunnan and Southwestern Sichuan of China

Ligularia Cass., （Compositae） is a highly diversified genus, and more than 100 species of which are distributed in the eastern Qinghai-Tibet Plateau and adjacent areas. Ligularia species have been studied with respect to secondary metabolites, and many sesquiterpenes of the furanoeremophilane type have been isolated from them. In order to find correlates among these variations, and ultimately understand the diversity-generating mechanism of Ligularia species in the Hengduan Mountains, we initiated an extensive study that uses furanoeremophilanes as a chemical index and the DNA sequence as a genetic index. Furanoeremophilanes have been detected conventionally by Ehrlich＇s test, which has been used in a search for novel natural products. As for the DNA sequence, we determined the nucleotide sequence of the atpB-rbcL intergenic region in the present study.     

Global Optimization of Feedforward Neural Networks

This paper proposes the compensating methods feedforward neural networkd (FNNs)which are very difficult to train by traditional Back Propagation(BP)methods.For an FNN trappedin local minima the compensating methods can correct the wrong outputs one by one until all outputsare right,then the network is located at a global optimum point.A hidden neuron is added to     

不同化学结合剂对铜氧化物的团聚和浸出行为

The chemical binder is one of the critical factors affecting ore agglomeration behavior and leaching efficiency. In this study, we investigated the effect of the type of binder and mass fraction of the H₂SO₄ solution used on the curing, soaking, and leaching behavior of agglomerations. The results revealed that Portland cement (3CaO·SiO₂, 2CaO·SiO₂, and 3CaO·Al₂O₃) was the optimal binder for obtaining a well-shaped, stable agglomeration structure. A higher extraction rate was achieved when using Portland cement than that obtained using sodium silicate, gypsum, or acid-proof cement. An excessive geometric mean size is not conducive to obtaining well-shaped agglomerations and desirable porosity. Using computed tomography (CT) and MATLAB, the porosity of two-dimensional CT images in sample concentrations L1–L3 was observed to increase at least 4.5vol% after acid leaching. Ore agglomerations began to be heavily destroyed and even to disintegrate when the sulfuric acid solution concentration was higher than 30 g/L, which was caused by the excessive accumulation of reaction products and residuals.