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New experimental data are obtained for pressure drop and entrainment for annular upflow in a vertical pipe. The 9.5-mm pipe has a hydraulic diameter similar to the subchannels in the fuel assemblies of water-cooled reactors. The test section has a length-to-diameter ratio of 440 to ensure fully developed annular flow. The pressure covers the range from 140 to 660 kPa. Therefore, the density ratio is varied by a factor of -4. This allows the investigation of the effect of pressure on the interfacial shear models. Gas superficial velocities between 25 and 126 m/s are tested, extending the range of previous data to higher gas velocities. The data are compared with well-known models for interfacial shear that represent the state of the art. Good results are obtained with the models by Wallis, and Henstock and Hanratty. When the model by Asali, Hanratty, and Andreussi is modified for the effect of pressure, the agreement is also good, and the data collapse with very little scatter. There is a close relationship between these models and mixing length theory such that the models may be viewed as correlations for the surface roughness. This points toward a more fundamental approach in terms of the interfacial structure.

In present study, an online analytical method using human periodontal ligament cell/cell membrane chromatography (hPDLC/CMC) combined with high-performance liquid chromatography/mass spectrometry (HPLC/MS) was used for direct recognition, separation, and identification of compounds for the first time from Scutellaria baicalensis Georgi (SBG) that are active on hPDLCs. Baicalein (BAI) and wogonin (WOG), which were identified as the active compounds of the ethyl ether extract of S. baicalensis Georgi (SBGEE), could bind to the same membrane receptor of hPDLC for simvastatin (SIM). Moreover, BAI (0.15-0.6 mg/L) and WOG (0.015-0.6 mg/L) had the capability to enhance cell proliferation, matrix calcification, and formation of calcified nodules, which are comparable to the activities of SIM (0.1 mg/L) in vitro. These observations are consistent with the K(A) of the various drugs. It is very important for the development of SBG used to treat periodontitis.

The title compound, C22H20O8, a product of oxidation of podophyl­lotoxin, a lignan of the phenyl­tetralin type, represents a synthon for potential antitumour agents. It has the same configuration of three chiral centres as the starting material, podophyl­lotoxin, and, as well as the latter, contains a γ-lactone ring trans-fused to the tricylic system. Non-classical C—H⋯O hydrogen bonds link the mol­ecules in the crystal structure into infinite chains along the a axis.

To understand the hepatitis C virus (HCV) genotype distribution in Yantai district of Shandong province, and to explore whether the HCV genotypes was relevant to the injure of liver through the index of liver function.Using specific PCR primers to amplify the HCV RNA 5' UTR/NS5B,then PCR products were sequenced by genetic analyzer. The genotypes were identified by alignment to the GenBank reference sequences and construction the phylogenetic tree of 5' UTR.Among 9 unpaid blood donors we detected two kinds of genotypes of 1b and 3a, respectively, 8 cases (88.9%) and 1 case (11.1%). Among 33 cases of hepatitis C patients we detected the 1b, 2a and 6a the three kinds of genotypes, respectively, 22 (66.7%), 10 (30.3%) and 1 (3.03%) cases. Subtype 1b is the advantage of popular genotype in HCV carriers from Yantai district, and the distribution of 1b was no significant difference in the different population (chi2 = 0.796, P = 0.373); The difference of indicator of liver damage in the different genotypes of subjects were significant (P0.05), the mean of ALT, AST of 2a-subtype carriers was significantly higher than the 1b-subtype population.The genetic diversity of HCV in Shandong Yantai district was presented. The main genotypes were 1b-subtype, and 3a and 6a-subtype was detected firstly. The genotype of HCV were relevant to the liver damage indicators, 2a-subtype hepatitis C virus infection in the liver cells may play an important role in the disease process.

To detect the effect of naringin on human periodontal ligament cells' (hPDLCs) proliferation,bone formation and OPG mRNA expression.hPDLCs were primarily cultured and identified in vitro through enzyme digestion combined tissue culture method. With 3-(4, 5-Dimethylthiazol-2- yl)-2, 5-diphenyltetrazolium bromide (MTT) method, enzyme linked immunosorbent assay and RT-PCR, the hPDLCs' proliferation, alkaline phosphatase (ALP) activity, expression of collagen protein-I and OPG mRNA were observed after treatment with different concentrations (100,10,1.0,0.1,0.01mg/L) of naringin at different times. SPSS16.0 software package was used for statistical analysis.Primary cultured hPDLCs had good shape; Significant promotion of proliferation,ALP activity and collagen protein-I expression of hPDLCs with naringin was found at the dose of 1.0 mg/L; and 1.0mg/L naringin regulated the expression of OPG mRNA in time-dependent manner.Naringin might significantly promote the proliferation of hPDLCs and conversion into the osteoblast.

To clone the peptidylarginine deiminase(PAD) gene of Porphyromonas gingivalis(P.gingivalis) and to be expressed in E. coli under the best conditions.With P.gingivalis strains ATCC33277 genomic DNA as a template, PCR was applied to obtain gene PAD which was then inserted into linear cloning vector PMD-18-T to construct clone recon. Recombinant PMD18-T-PAD was cloned and analyzed with PCR and restriction endonuclease,and PET-28a expression vector was digested by Xhol and Ncol,their products were linked to construct expression plasmid PET-28a-PAD under certain connection system. The recombinant expression plasmid PET-28a-PAD which had been confirmed correctly was transformed to E. coli competent cells BL21 and induce the expression of PAD with IPTG of different density and time. With His Tag monoclonal antibody as the first antibody, the expressed fusion protein was characterized by Western blot.DNA sequencing showed that the fragment was same as the sequence published in NCBI. Under the condition of 37 degrees centigrade, 0.5mmol/L IPTG, 250r/min shaking for 6 hours, the PAD could be highly expressed.The PAD is successfully cloned and expressed in E. coli which can be further uesd to study the immunity of PAD and the homologues antibody preparation.

Design and synthesis complementary DNA sequences of 3 pairs of short hairpin structure and a pair of negative control sequence by RNA interference technique and construct and identify a lentiviral interference vector with human BIRC5 gene as target gene.The designed and synthesised Single-Stranded primer were annealed to Double-Stranded oligo sequences and subcloned into linear pMAGic lentiviral plasmid vector digested by enzyme Age I and EcoR I. Screening positive clone after transformed into DH5α competent cells and identified by PCR amplification and DNA sequencing.335 bp straps of positive clone and 298 bp straps of negative clone form PCR amplification production have been obtained after gel electrophoresis, the designed and synthesised sequences have been contained in these clone straps confirmed by the result of DNA sequencing.Four pairs of BIRC5 shRNA recombinant lentiviral expression vector were constructed successfully, which laid the foundation for researching the inhibition of BIRC5 siRNA target against tumor cells proliferation, induction apoptosis and gene therapy.

To clone the glyceraldehydes 3-phosphate dehydrogenase (GAPDH) gene of Porphyromonas gingivalis (P. gingivalis) and to induce its fusion expression in E. coli.GAPDH was obtained by PCR and was inserted into cloning vector pMD-18-T to construct clone recon. Double enzymes digest the recon pMD18-T-GAPDH and the prokaryotic expression vector pET-32a and then connect to get the expressing recon pET-32a-GAPDH. The recombinant expression plasmid which had been confirmed by enzymes digestion was transformed to E. coli competent cells BL21 and induced the expression of GAPDH with isopropyl beta-D-1-thiogalactopyranoside (IPTG) of different density.DNA sequencing showed that the fragment was 99.802% the same to the sequence published in NCBI. Under the best density, IPTG could be highly expressed.The GAPDH had been successfully cloned and expressed in E. coli which gets ready for the following experiment to study the immunity of GAPDH and the homologues antibody preparation.

To screen a variety of Porphyromonas gingivalis (Pg) common outer membrane proteins with two-dimensional liquid phase fractionation (PF2D) and matrix-assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF-MS) and provide candidate target antigen for the design of vaccines with cross protection against a variety of Pg.The outer membrane proteins of Pg301, PgATCC33277 and PgW83 were extracted through ultracentrifugation, and then they were separated by ProteomeLab PF2D protein fractionation system. After separation, the outer membrane proteins were obtained through comparison, and the primary structure of the proteins was identified by MALDI-TOF/TOF-MS and database.Ninety-nine protein samples out of 3 strains of Pg were obtained after the high performance chromato focusing (HPCF) separation process. B7 fractions of 3 strains of Pg were separated by the reversed-phase high performance liquid chromatography (RP-HPCL) separation process. After comparison of peak and retention time of chromatogram, the 8 common protein peaks of 3 strains of Pg were confirmed. The protein samples were identified by MALDI-TOF/TOF-MS, and one of them was known protein arg-gingipain A.PF2D protein fractionation system is of good reproducibility and high resolution. A combination of PF2D and MALDI-TOF/TOF-MS can be used to identify the common outer membrane proteins of Pg.

To analyze the common outer membrane proteins (OMP) from Porphyromonas gingivalis (Pg) by surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) and to provide antigens for the subsequent experiments in screening vaccine for periodontitis therapy.Four strains of Pg were cultured under anaerobic conditions. The common OMP was extracted through ultracentrifugation and SELDI-TOF-MS was employed to detect the expressions of proteomes by chip H(50). The data was analyzed by Biomarker Wizard.Four kinds of strains of OMP fingerprint spectrum were obtained. Seventy-one proteins of PgATCC33277, 74 proteins of PgW83, 76 proteins of PgW301 and 72 proteins of Pg381 were captured by chip H(50). Thirteen common proteins were identified according to fingerprint spectrum. There was only 1 of the 13 common proteins identified in NCBI protein bank.SELDI-TOF-MS has good reproducibility and high sensibility and can be used to identify the common OMP of Pg. The 13 proteins have a potential value in the screening vaccine candidate antigen sites for periodontitis.

To clone the FimA gene of fimbriae from Porphyromonas gingivalis (P. gingivalis) and to construct prokaryotic expression vector which was induced in E.coli BL21(DE3)pLyS in the form of fusion protein expression and to identify, purify the product of its expression.To clone the FimA gene of fimbriae from P. gingivalis and to construct prokaryotic expression vector pET15b-FimA vector which was transformed into the competent cells of BL21(DE3)pLyS. The expression of fusion protein was induced by isopropyl beta-D-1-thiogalactopyranoside (IPTG). With anti-6xHis Tag monoclonal antibody as the first antibody, the expressed fusion protein was characterized by Western blot and purified by Co(2+)-NTA affinity chromatography.Cloned FimA gene sequences and inserted into expression vector of the FimA sequences were related to the sequence in GenBank database showed 100% homology. IPTG induced and then identified by Western blot showed a fragment of 4.1 x 10(4) has been expressed. Co(2+)-NTA affinity chromatography column was used to obtain high concentrations of FimA purified protein.The recombinant prokaryotic expression vector of pET15b-FimA was constructed and was expressed and purified successfully in E. coli BL21 (DE3)pLyS. This study laid the experimental foundation to further prepare for monoclonal antibodies of fimbriae of P. gingivalis and to develop the subunit protein vaccine of prevention of periodontitis.

This paper presents a two-level place names identification method based on N-shortest path and Conditional Random Fields(CRFs) aiming at solving the low recall rate problem in Chinese place names identification. First, the rough segmentation method based on N-shortest path is used to improve the recall rate of Chinese place names identification at low level; Second, the result of rough segmentation is submitted to high level as one of the features of high-level place names identification. High level’ s CRFs model uses the feature which submitted by low level, single and complex features of place names words to tag the text. Adding the complex feature is conducive to mine the context information and improve accuracy rate of place names identification, and the result of text tagging could be combined with rules to identify place names finally. This two-level model ensures a high recall rate and improves the accuracy rate. During experiment, choose the mature corpora of People’ s Daily in January 1998 as training samples, which include 3128 place names(except duplicate names), and extract articles of People’ s Daily in 2003 randomly to carry out the test. Experimental results achieve a high recall rate, and this method is proved to be practical and effective.

To explore the method for obtaining olfactory ensheathing cells from human fetal olfactory mucosa by cell culture for selective adhesion in the presence of neurotrophin-3 (NT3) and low-concentration serum.The olfactory ensheathing cells were cultured alternatively in DMEM/F12 culture medium containing 10% fetal bovine serum (FBS) and the medium containing NT3 and 2.5% FBS every 72 h. The cells were observed for morphological changes and identified using immunocytochemistry with P75NTR and GFAP, and the cell purity was estimated.The olfactory ensheathing cells from human fetal olfactory mucosa were positive for P75(NTR) and GFAP, and in in vitro culture, the cells exhibited dipolar or tripolar appearance with long thin neurites. On the 9th day of cell culture, the purity of the olfactory ensheathing cells reached about 83%.The olfactory ensheathing cells can be obtained by in vitro culture for selective adhesion in the presence of NT3 and low-concentration serum.

An iterative algorithm can be modeled by a cyclic data-flow graph. The bottleneck for scheduling cyclic data-flow graphs lies on dependencies that form cycles. The maximum computation-time-to-delay ratio among all the cycles in the graph, gives a lower bound on pipeline schedule length. In this paper, a framework for algebraic transformations is proposed to reduce the lower bound. A novel algorithm is proposed to apply transformations within iterations or over iteration boundaries. A set of beneficial transformations are chosen, and applied simultaneously in each pass of the algorithm. A measure of criticalness on loops is used to identify transformations leading to potential lower bound reduction. Experimental results show that substantial reductions on the lower bound are achieved, and shorter pipelined schedules are generated.

Multiprocesssor systems have emerged as an important computing means for real-time applications and have received increasing attention than before. However until now, little research has been done on the problem of on-line scheduling of parallel tasks with deadlines in partitionable multiprocessor systems. In this paper, we propose a new on-line scheduling algorithm, called Deferred Earliest Deadline First (DEDF) for such systems. The main idea of the DEDF algorithm is to defer the scheduling as late as possible, so that a set of jobs is scheduled at a time instead of one at a time. For processor allocation using DEDF, we have introduced a new concept-Available Time Window (ATW). By using ATW the system utilization can be improved and thereby enabling the system to meet the deadline of more number of tasks. Simulation results for a hypercube indicate that the DEDF algorithm performs significantly better than the earlier proposed Buddy/RT and Stacking algorithms for a wide range of work loads.

Loop pipelining can be applied to a cyclic data-flow graph to reduce the iteration bound, which is the maximum computation-time-to-delay ratio among all the cycles in the data flow graph. Algebraic transformations can reduce the iteration bound substantially. However, resource constrained algebraic transformations for loop pipelining remains a hard problem because of the inherent nature of loop pipelining. In this paper, we propose a new method based on distribution graphs to solve this problem. A novel algorithm for algebraic transformation with resource constraints is provided, which works for non-pipelined schedules as well. Experimental results show that our algorithm is promising.