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The changes of acid value, peroxide value, phosphorus content, phytosterols, tocopherols and diglycerides of rapeseed oil, as well as the composition and content of phospholipids in degummed oil feet (oil sediment) were investigated under different degumming conditions using rapeseed crude oil as raw material. There were significant differences in degumming capabilities among water degumming and enzymatic degumming, enzymatic degumming showed more competence than water degumming, meanwhile, phospholipase A1 enzymatic degumming was more thorough compared with that of phospholipase C. The peroxide value and acid value of rapeseed oil showed a decreasing trend after degumming, additionally, the acid value of phospholipase A1 decreased the least. The content of tocopherols and phytosterols in degummed oil decreased slightly, with a maximum decrease of about 5%. Diacylglycerols content in phospholipase C enzymatic degumming increased significantly, meanwhile, the ratio of 1,3-diacylglycerols to 1,2-diacylglycerols in degummed oil decreased, with the ratio ranging from (2.2-3.0):1. There were significant differences in the composition and content of phospholipids in degummed oil feet after different degumming processes, which phospholipase A1 enzymatic degumming oil feet owned the highest content of lysophospholipids, and phospholipase C enzymatic degumming oil feet had the highest content of phosphatidylinositol. [ABSTRACT FROM AUTHOR]

The paper divided the decentralized lookup algorithms in peer-to-peer networks into two classes: structured and unstructured. The lookup mechanisms, network topology and lookup efficiency of these two types of algorithms were compared. From the comparison, it is concluded that there exists tradeoff in lookup algorithms. For example, to improve the time efficiency, the algorithm has to increase the routing table size or network overhead. The paper can be a reference for the design of new lookup algorithms or application of peer-to-peer lookup algorithms in related areas such as Grid computing. [ABSTRACT FROM AUTHOR]

Based on the artificial immune system's clonal selection theory and shape space theory, this paper brought forward a novel shape-space based clonal selection algorithm. This algorithm is used to the application of multi-modal function optimization. The results indicate the proposed method is much better than other methods. [ABSTRACT FROM AUTHOR]

Anomaly detection techniques can detect novel attacks. This paper proposed two approaches based on statistical techniques. One of them is based on a maximum entropy method, which first educes the distribution of user's normal behavior, then decides the discrimination limit. The other is based on Knearest neighbor (KNN) classifier. It is probabilistic but distribution-free. The preliminary experiments with 1999 DARPA tcpdump data show that both method can effectively detect intrusive attacks. In the end, a comprehensive comparison of these two methods was given. [ABSTRACT FROM AUTHOR]

This paper sketched out the design of a decentralized, scalable, self-organizing and fault-tolerant location algorithm for peer-to-peer networks. The principle of the algorithm is as follows. A finite linear space, whose size is Mκ, is evenly divided into M parts. Again, the sub-part is recursively divided into M equal parts until all sub-parts can only contain one unit (point). Data and node's identifiers can be mapped onto the points of the linear space by using a hash function. Each node's routing table contains the location information of a small subset of other nodes, whose identifiers have some special relations to the present node's identifier in the linear space. With the routing table, one node can locate other node that is responsible for the given data items within O (log N) hops. The results from simulation experiments show that increasing the value of M can enhance the routing performance of the algorithm. In a simulation network with 104 nodes, if the value of M is 16, the average locating path length of the algorithm is only 70%/0 of that of Pastry and Tapestry. [ABSTRACT FROM AUTHOR]

This paper advanced a new algorithm to detect network intrusions using sequences of system calls. This algorithm uses a data structure called weight tree, first it uses normal system call trace to build weight tree forest, which have to be pruned periodically in order to learn new pattern and eliminate impurity. Then it scans abnormal trace using those trees and gets the corresponding weight sequences. Those weight sequences can tell us if something abnormal has happened or not. It acquired good results in experiment. [ABSTRACT FROM AUTHOR]

This paper brought forward a new immune algorithm, multi-level negative selection algorithm. Compared with Forrest's negative selection algorithm, it enhances detector generation efficiency in essence. This algorithm integrates clonal selection process into negative selection process. Based on the analysis, this algorithm was applied to network intrusion detection and has a very good result. [ABSTRACT FROM AUTHOR]

Ceramic coatings have excellent properties of high hardness, outstanding wear resistance, corrosion resistance and so on, which make them become the hot spot of research at present. Sol-gel technology is one of the mature and simple methods to prepare ceramic coatings. In this paper, the research achievements in system design and physical and chemical properties of ceramic coatings prepared by sol-gel technology at home and abroad were reviewed. A comparative analysis was conducted on the existing problems of several ceramic coatings at present, and their extension technologies and development prospects were summarized and prospected, which would provide a certain reference for the design and preparation of ceramic coatings with excellent performance and high cost-effectiveness in the future.

Objective: To screen the genes that may play an important role in the carcinogenesis of nasopharyngeal carcinoma (NPC)., Methods: Microdissection and cDNA genechip hybridization techniques were used to examine the differentially expressed genes in NPC tissue, the surrounding and adjacent tissues of NPC, and the nasopharyngeal inflammation tissue. The fluorescent signals on cDNA chip were scanned and the results of hybridization analyzed by image processing software., Results: Many differentially expressed genes were identified between the three samples, including many different types of genes, such as those responsible for signal and protein transmission, oncogene and tumor suppression genes, immune-associated genes, apoptosis genes and DNA binding and transcription factor genes., Conclusion: The carcinogenesis of NPC involves many genes of a variety of types, suggesting its complex process.

The GATA-1 of Xenopus (xGATA-1), which has two subtypes xGATA-1a and xGATA-1b, is a necessary factor for erythroid differentiation and maturation as similar as that of other GATA-1s. Although both xGATa-1a and xGATA-1b are able to stimulate erythropoiesis, only xGATA-1b is capable of inhibiting neurogenesis in Xenopus embryos. Compared between their structures, xGATA-1a and xGATA-1b are very similar in nucleotide and amino acids composition, but not identical. Therefore, it is responsible for studying the role of the diverse codons between the two genes, so the desired mutations: S(168), H(169) double deletion and point mutation of T(304)-->A, T(359)-->A, were introduced into xGATA-1b gene through site-directed mutagenesis. Then, mRNA from each mutant as well as wtxGATA-1b was co-injected with DN-BR mRNA or separately injected into Xenopus stage 2 embryos, and the role of mutants in erythropoiesis and neurogenesis was analyzed by using animal cap culture system. The results showed that the neural-inhibiting activity of xGATA-1b, but not hematopoiesis-inducing activity, was aborted because of deletion of Ser(168) and His(169) or point mutation of T(359)-->A. So it is demonstrated for the first time that Ser(168) and His(169) or Thr(359)in xGATA-1b may be one of the structural basis for explanting the different function between xGATA-1b and xGATA-1a.

Objective: To study methods of diagnosis and treatment for atypical pneumonia (Severe Acute Respiratory Syndrome), outbreak of the illness in Guangzhou during Jan. - Mar., 2003., Methods: 190 cases with atypical pneumonia were analyzed, and the cases were admitted in Guangzhou municipal First Hospital and Guangzhou municipal Eighth Hospital., Results: Patients were infected by close quarters contacting each other. All patients manifest high fever, and accompany by dyspnea, cough, palpitate, weakness, headache and swirl. Other 46 cases were accompanied by diarrhea. Most of patients, manifestation of lungs was negative. Chest X-ray, shadow of lungs were light in beginning, and change to severity slowly or suddenly during 5 - 10 days. Of these cases, 36 cases develop to ARDS and 11 cases died with severity ARDS. Using general antibiotic was of no effect for the illness. Continual positive airway pressure (CPAP) and glucocorticoid was required that can control deprivation of the disease when toxicosis symptom of patients was severity and shadow of lungs diffuse more and more., Conclusion: Infectivity of the illness is evidence and spread by airway. Using general antibiotic was of no effect for the illness. Continual positive airway pressure (CPAP) and glucocorticoid are effective for control of the disease.

Background & Objective: The mechanism of how stromal cell play an important role in nasopharyngeal carcinogenesis is now a hotspot. This study was designed to elucidate the possible mechanism of stromal cell in the occurrence and progression of nasopharyngeal carcinoma (NPC) through the analysis of the characteristics of gene expression in pericancerous stromal cells of NPC by cDNA array., Methods: The atlas human select tumor arrays were used to compare the expression profiles between NPC tissue and NPC cell lines., Results: Pericancerous stromal cells in NPC expressed at least 40 genes specifically., Conclusion: The specific expression of these genes in pericancerous stromal cells provides energy materials for growth of NPC cells; furthermore, it can accelerate the degradation of extracellular matrix, thus promoting the metastasis of NPC cells.

Background & Objective: Microdissection has become indispensable for the selective analysis of stroma-free tumor cell. However, To obtain sufficient RNA from microdissected cells is difficult. The study was designed to seek a specific way to separate nasopharyngeal carcinoma (NPC) cells from stromal cells and to amplify the RNA from microdissected NPC cells., Methods: NPC cells were obtained using microdissection from frozen NPC tissue sections, then RNA was extracted from the microdissected NPC cells and reverse transcribed in vitro. The expression levels of beta-actin and GADPH in amplified RNA were detected using RT-PCR., Results: About 20,000-40,000 NPC cells were obtained, RNA was extracted from the cells, about 0.5-2.5 kb RNA fragments were obtained after RNA linear amplification and beta-actin and GADPH levels were integral., Conclusion: Microdissection combined with RNA linear amplification can be used to successfully obtain pure NPC cells, the integrity of amplified RNA is good and can be used in further research.