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Fick’s second law and its analytical solution were usually used for analysis of chloride diffusion in concrete. But discretization of the continuous variables is more appropriate in modeling and discrete model is more suitable for engineering applications. In this paper, Difference Equation equivalent to partial differential equation was established with the difference method, and three-dimensional differential equation of Fick's second law was resolved. Based on this study，the convergence conditions of difference Equations for one-dimensional, 2D and 3D diffusion was given.

In this paper, concrete was analyzed as a composite consisting of coarse aggregate, mortar matrix and interfacial transition zone (ITZ). Because permeability of each phase are not the same, ITZ will affect the concrete permeability. Effect of ITZ on the concrete permeability was studied by laboratory test and numerical analysis.The diffusion coefficient of ITZ, mortar,and concrete can be caculated by laboratory test. The results indicate that the diffusion coefficient of ITZ is far greater than mortar，which is about 40 times of mortar. The chloride ions diffusion ignoring ITZ and considering ITZ were simulated, the results show that the diffusion coefficient of concrete was bigger when the ITZ was considered, which was closer to the experimental results.

Considering the co-action of micro-pile and soil nailing, the state equation of limit equilibrium and the performance function of inner global stability of foundation pit supported by the micro-pile composite soil nailing is set up with the slope limit equilibrium theory and the circular sliding slice method. The calculating model of sliding surface for inner global stability of foundation pit is established with the geometry controlling method and the optimization searching of the most dangerous sliding surface is achieved. Then with the shear strength indexes of soil as random variables, the partial derivatives of the performance function to all random variables is deduced and the reliability index of inner global stability of foundation pit supported by micro-pile composite soil nailing is calculated with the design checking point method. Finally, the effects of coefficients of variability of the random variables on reliability index are analyzed.

The study presented herein has been carried out in order to investigate the chloride diffusivity of recycled aggregate concrete (RAC). Meanwhile, the effect of the binder type, involving cement replacement materials such as, fly ash, slag and silica fume on the chloride diffusivity has also been investigated. For this purpose, RAC and concrete containing the different type of binders with w/b ratios of 0.35, 0.40, 0.45, 0.50, 0.55, and 0.60 were used. As a result, the chloride diffusion coefficient of RAC is higher than that of natural concrete and the partial replacement of cement with fly ash, slag and silica fume is effective in decrease in the chloride diffusion coefficient, measured by a rapid chloride conductivity test.

Based on the limit equilibrium theory and the circular slip surface method, the state equation of limit equilibrium and the calculation model of the most dangerous sliding surface for inner global stability of foundation pit supported by the prestressed anchor composite soil nailing is established with the disturbing force method. And the searching and solving method of the most dangerous sliding surface is optimized with the SLP optimization method and the simplex optimization method. Then with the mechanical parameters of soil as random variables, the reliability index of inner global stability of foundation pit is calculated with the design checking point method. Finally, a practical project is used to analyze the sensitivity of the reliability index to the coefficients of variability of all random variables.

Consideration of influence of the groundwater seepage and supporting measures to deep-foundation pit,the deformation characteristics of surrounding soil of the foundation pit are given. Seepage and deformation characteristics of surrounding soil are simulated to predict deformation of the deep foundation in ha er bing and stability of deep-foundation pit is analyzed base on the influence of the seepage. The analysis results are compared with observed data and it is showed that the calculated results with the model considering coupling response of permeability coefficient are closer to observed value than those results with the other model. So, the model considering fully coupling response of permeability coefficient is reliable and applicable.

Based on BAYES data processing theory, a new method of fuzzy probability is proposed for the parameter reliability of small sample. Prior distribution of fuzzy parameter is obtained by stochastic weighted method, then posterior distribution of fuzzy parameter is got by the method of conjugate distribution. In the end, the formula of fuzzy membership function is constructed, and probability of fuzzy events is solved.The study of this paper aims at the membership function which is deduced in the condition that mean is known and deviation is unknown in normal population distribution. At the same time using information of small sample of actual experiment, the study fully utilizes prior information, so, it is convincing to evaluate reliability of fuzzy parameter. It is obviously economical.

Sputum transportation from county-level to prefecture-level is an ideal strategy to cover the shortage of the laboratory capability in the resource-poor setting. Here, we firstly evaluated the feasibility of sputum transportation system in China by analyzing the culture and molecular diagnosis results from 1982 smear-positive patients with different delay in processing for culture. In this study, the total contamination rate was 2.32% and the total smear positive/culture negative (S+/C-) rate was 7.57%. We found that sputum specimens refrigerated for no more than 7 d before mycobacterial detection did not affect culture significantly. In addition, the invalid result rates among 0-3 d, 3-7 d, and 7+ d group were 3.63%, 3.14%, and 12.48%, respectively. Statistic analysis revealed that molecular diagnostic results while the invalid result rate of genechip for the specimen with more than 7 d delay was significantly higher (P0.001). The refrigerators equipped in county laboratories, transport at low temperature and frequent transport services once a week will ensure the feasibility of sputum transportation system in China.

Truffles are ascomata of ectomycorrhizal hypogeous fungi associated with endemic Pinus tabuliformis in Mount Helan National Nature Reserve in Inner Mongolia, China, was investigated f in soil cubes taken from pure P. tabuliformis stands. The objectives of this study were (i) to develop a molecular method to detect mycelia of Tuber spp. in soil and (ii) to test for mycelial distribution around two truffle-bearing P. tabuliformis trees in a truffle orchard. Isolation of total DNA from soil was performed, followed by PCR amplification with Tuber spp.-specific primers and restriction analysis. To address the detection sensitivity level, soil samples were inoculated with known amounts of gleba of Tuber spp. Mycelium was detected primarily within the area defined by the truffle burn and within the top 35 cm of the soil in all directions from the trees.

To evaluate the reliability of thiophen-2-carboxylic acid hydrazine (TCH) test for identification of Mycobacterium bovis (M. bovis).A total of 4069 clinically isolated strains were identified by P-Nitrobenzoic acid medium (500 mg/L) and TCH medium (5 mg/L). Mycobacterium tuberculosis (M. tuberculosis) complex strains susceptible to 5 mg/L TCH were further tested for susceptibility to 2 mg/L TCH. Spacer oligonucleotide typing (spoligotyping) and multi-loci PCR were also performed to identify TCH susceptible strains.Among the 4069 isolated strains there were 3929 strains belonging to M. tuberculosis complex (MTBC) of which 245 were susceptible to 5 mg/L TCH. Of these 245 strains, 20 were also susceptible to 2 mg/L TCH, while only 1 strain was identified to be M. bovis by both spoligotyping and multi-loci PCR.TCH susceptibility test (either 5 mg/L or 2 mg/L) is not a reliable method for identification of M. bovis.

To study the tuberculosis clustering areas and the changing trend, from 2008 to 2010, so as to provider the reference for tuberculosis control.Global spatial autocorrelation and SaTScan methods were used to detect and analyse the spatial clustering of total tuberculosis notification rate and the new smear-positive pulmonary tuberculosis notification rate, at the provincial level from 2008 to 2010.The spatial clustering (SC) phenomenon was significant on total notification rate and new smear-positive pulmonary tuberculosis notification rate from 2008 to 2010 (P0.01). The coverages of clustering areas on total notification rate showed a reduction from 19 provinces to 14 provinces, distributed in the south, west and north-east areas of China. The coverages of clustering areas on new smear-positive pulmonary tuberculosis notification rate concentrated in 14 provinces which covered the south and north-east of China.The disease burden and the risk of transmission in the clustering areas of tuberculosis both located in the south and the north-east of China. The disease burden of tuberculosis was high in the west of China, but not the areas with high risk of transmission.

To preliminarily understand the genotyping characteristics regarding the variable number tandem repeats (VNTR) of Mycobacterium tuberculosis clinical isolates so as to provide evidence for the development of tuberculosis control and prevention programs in Fujian province.Fifteen VNTR locus sets were used to detect the clinical isolates from the fifth surveillance project on tuberculosis resistance, in Fujian province. BioNumerics version 4.5 were used to analyze the cluster from the results generated by genotyping.313 Mycobacterium tuberculosis isolates were divided into 9 clusters, including I, II, III, IV, V, VI, VII, VIII and IX, with the number of 220, 9, 48, 2, 1, 3, 10, 10, 10 isolates, respectively. Cluster I was the major lineage, accounting for 70.3% (220/313) of the total. Resistance rates of cluster I isolates to isoniazid, streptomycin, ethambutol and multi-drug-resistant were not statistically different from other clusters (P0.05). However, resistance rate to rifampicin (RFP) was significantly higher than that of other isolates of the clusters, 33.2% (73/220) vs. 20.4% (19/93) (P0.05).The strains isolated from Fujian province showed significant polymorphism on genotyping. Cluster I seemed to be the dominant, calling for the close monitoring program on cluster I strains.from our initial studies demonstrated the existence of significant correlation between cluster I strains and drug resistance to RFP.

The electronic retrieval of ectomycorrhizae is regarded as researching object in this paper. And the ectomycorrhizal digital information retrieval system was designed by combining with Microsoft Visual Basic 6.0 Enterprise Edition database management system and Structure Query Language. The system realized electronic management and retrieval of local ectomycorrhizal information. In this software, the keywords of retrieval included family, genus, formal name, Chinese name, Latin, morphological characteristics, habitat collection people, collection places, and protect class and so on. It provided reference for these problems of species identification and digital management of herbarium.

To explore the roles of BCG-depleted immunodominant antigens derived from M. tuberculosis in serological tests for tuberculosis (TB).Four different combinations of current mainstream antigens used for serological diagnosis of TB were selected: Reagent A [Mycobacterium TB immunoglobulin G (IgG) antibody assay kit]; Reagent B (Mycobacterium TB detection kit); Reagent C (M. tuberculosis-specific antibody detection kit); Reagent D [Active TB antibody detection enzyme-linked immunosorbent assay (ELISA) system]. Immunological methods of Western blot, colloidal gold and ELISA were developed to test the antibodies in 109 patients with active tuberculosis (TB) and 97 healthy populations. They were divided into purified protein derivative of tuberculin (PPD) positive and negative groups. Bayesian statistical analysis was used to analyze the influences of variable combinations of different antigens on the detection accuracy of TB.For Reagent A, B, C, D, the detection rates of IgG antibodies in the patients with active TB were 80.0%, 66.7%, 80.7%, 56.0% versus 23.9%, 8.9%, 6.6% and 1.0% respectively in healthy populations. The TB antibody detection rates in four TB patient populations were all higher than that in healthy populations (χ(2) = 47.53, 51.59, 90.48, 69.68, all P0.01). The TB antibody detection rates of Reagents A and B increased with the intensity of positive reaction to PPD in healthy populations (χ(2) = 2.124, 2.220, all P0.05) while those of Reagents C, D in healthy populations were irrelevant to PPD reaction. (χ(2) = 0.122, 0.479, all P0.05). Reagent D has the highest accuracy. The immunoglobulin M (IgM) antibody detection rate of Reagent D was only 2.1% in the patients with active TB.The detecting sensitivity of TB IgG antibodies is associated with antigen selection. And it is also positively correlated with the number of combined antigens. High-sensitivity detection is often accompanied by a loss of specificity. With the BCG-depleted antigens derived from M. tuberculosis, the specificity of serological test for TB may significantly improve.

To study the positive rate of smear and culture in different sputa from smear-positive patients with tuberculosis, and to discuss the criteria of sputum selection for smear and culture.The results of smear and culture of sputum samples from 3813 cases during tuberculosis drug-resistance baseline survey in 2007 were retrospectively analyzed. The positive rates of smear and culture of spot sputum, night sputum and morning sputum were compared, and the culture positive rate of sputum samples with 1-2 acid fast bacilli (AFB)/300 fields was summarized. The χ(2) test was used for comparison.The smear positive rate of spot sputum, night sputum, and morning sputum was 75.2% (2868/3813), 87.9% (3350/3813), and 89.4% (3408/3813) respectively. The percentage of cases which were positive for all the 3 sputum samples was 64.5% (2460/3813), while that for 2 samples and 1 sample was 23.4% (893/3813) and 12.1% (460/3813) respectively. The cumulative smear positive rate of spot sputum plus morning sputum reached 96.9% (3695/3813) of the rate combined from the 3 sputum samples. The culture positive rate of spot sputum, night sputum, and morning sputum was 97.8% (1654/1691), 96.7% (3006/3107) and 97.2% (2473/2543) respectively. For the smear positive cases, the positive rate of 2 sputum culture increased only 1.7% - 2.8% compared with that of 1 sputum culture. The culture positive rate of samples with a smear result of 1 - 2 AFB/300 fields was 90% (98/109).When spot sputum and morning sputum are collected for the diagnosis, the number needed for smear can be decreased from 3 to 2. For smear-positive cases, if sputum is selected for culture according to the smear result, the number needed for culture can be decreased from 2 to 1. A smear result of 1 - 2 AFB/300 fields is of considerable diagnostic value for tuberculosis.

As a new branch of mathematics, Fractal Geometry has been widely used in civil engineering field. This study investigated its relationship between internal fractal dimension of aggregate fracture and surface porosity after destruction of coral aggregate concrete under pressure, cutting reveals the microlevel concrete aggregate injury characteristics

The objectives of this study were to monitor the stability of rifampin (RIF) in Löwenstein-Jensen medium (L-J medium) and 7H9 broth, which are the media commonly used for drug susceptibility testing (DST) of Mycobacterium tuberculosis . Rifampin degradation in stock solution, 7H9 broth, and L-J medium and during the inspissation process for L-J medium preparation was serially monitored by high-performance liquid chromatography (HPLC). L-J medium-based DST was conducted to examine the effect of L-J medium storage on the DST outcome. The RIF stock solution was stable for at least 3 months when kept at either 4°C or −20°C; RIF in 7H9 broth and L-J medium was almost 50% decayed after 1 week of storage at 37°C, and rifampin could not be detected in 7H9 or L-J medium after 3 weeks or 6 weeks of storage at 37°C. Approximately half of the drug was decomposed after 4 months of storage at 4°C for both media, and after 6 months of storage at 4°C, RIF in L-J medium was undetectable, while 38% of RIF remained in 7H9 medium. Approximately 21, 24, 29, and 35% RIF degradations were detected when the L-J medium was coagulated at 75°C, 80°C, 85°C, and 90°C, respectively. The DST outcomes when using L-J medium stored for different periods of time were consistent with the RIF concentration monitoring data. Rifampin in stock solution is stable for at least 3 months at a reduced storage temperature. Media containing RIF should be prepared strictly according to validated standard operating procedures. RIF degradation is a possible reason for false resistance categorizations of M. tuberculosis isolates in the clinical laboratory.

An increasing incidence of disease caused by nontuberculous mycobacteria (NTM) is being reported. The purpose of this study was to determine the isolation rates of NTM from various clinical specimens, and their antimicrobial susceptibility patterns, over a 4-year period in Shanghai.All NTM isolated between 2005 and 2008 at Shanghai Pulmonary Hospital, a key laboratory of mycobacteria tuberculosis in Shanghai, China, were identified with conventional biochemical tests and 16S rRNA gene sequencing. Antimicrobial susceptibility for all NTM was determined using the BACTEC MGIT 960 system.A total of 21,221 specimens were cultured, of which 4868 (22.94%) grew acid fast bacilli (AFB), and 248 (5.09%) of the AFB were NTM. The prevalence rate of NTM was determined as 4.26%, 4.70%, 4.96% and 6.38% among mycobacteria culture positive samples in years 2005, 2006, 2007 and 2008 respectively. These data indicated that the prevalence rate has continuously increased. Sixteen different species of NTM were identified, the most commonly encountered NTM in Shanghai were M. chelonae (26.7%), followed by M. fortuitum (15.4%), M. kansasii (14.2%), M. avium-intracellulare complex (13.1%) and M. terrae (6.9%). The rare species identified were M. marinum, M. gastri, M. triviale, M. ulcerans, M. smegmatis, M. phlci, M. gordonae, M. szulgai, M. simiae, M. scrofulaceum and M. xenopi. The five most commonly identified NTM species showed high drug resistance to general anti-tuberculosis drugs, particularly, M. chelonae and M. fortuitum appear to be multi-drug resistance.The prevalence of NTM in Shanghai showed a tendency to increase over the course of the study. The five most commonly isolated NTM species showed high drug resistance to first line anti-tuberculosis drugs.

To investigate the distribution of the Beijing genotypes of Mycobacterium tuberculosis (M. tuberculosis) and the relationships between Beijing genotype strains and drug-resistant phenotypes in China.Clinical isolates were collected during a 9-month research period from April to December in 2008 in six geographic regions of China. One isolate that had been biochemically confirmed to be a member of the M. tuberculosis complex was collected from each patient. The demographic data of the patients (eg. sex, age, and history of tuberculosis) as well as the drug resistance patterns and sources of the clinical isolates were collected. Drug susceptibility testing was performed using proportion method. Beijing genotypes of M. tuberculosis were identified by spacer oligonucleotide typing or insertion of IS6110 in the genomic dnaA-dnaN locus.Among the 410 M. tuberculosis clinical isolates, 67.1% (275/410) isolates were Beijing genotypes of M. tuberculosis. Significantly larger proportions of tuberculosis patients were infected with Beijing genotypes in the northeastern regions of China than that of in the central-western regions (chi2 = 20.50, P = 0.000). No significant associations were found either between Beijing genotype strains and patients' age, sex, or treatment history. Multidrug-resistant isolates and rifampin-resistant isolates were more common among Beijing genotype strains than among non-Beijing strains (P = 0.002, P = 0.005).About two third of the clinical isolates of M. tuberculosis in China are Beijing genotypes. Beijing genotype strains are not correlated with patients' age, sex, treatment history. People living in the northeastern regions of China are more susceptible to Beijing genotypes than those living in the central-western of China. Beijing genotype strains tend to be rifampin-resistant or multidrug-resistant.

To explore the feasibility of utilizing polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis combined with Southern blot to detect ofloxacin (OFLX)-resistant Mycobacterium tuberculosis, and figure out the boundary between the OFLX-susceptible and resistant Mycobacterium tuberculosis.OFLX-resistant Mycobacterium tuberculosis bacilli were induced in vitro and their minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC) were determined. The 320 bp segments of gyrA gene were amplified by PCR and their polymorphism was tested by SSCP from H(37)Rv, H(37)Ra and those induced OFLX-resistant strains. To prove the repeatability of PCR-SSCP combined with Southern blot, 36 clinical isolated OFLX-resistant strains were tested.All of the 85 OFLX-resistant mutations involved in this study were identified to have gyrA mutations. The results showed that there was an overlap if OFLX 10 microg/ml was used as a criteria for discriminating susceptible and resistant strains. Compared with the H(37)Ra, the similar single-stranded shift caused by the single-stranded conformation change was viewed in the 36 clinical isolated OFLX-resistant strains by PCR-SSCP combined with Southern hybridization.PCR-SSCP analysis combined with Southern blot can clearly distinguish OFLX-susceptible from OFLX-resistant strains. The results suggest that as a cut-off point between OFLX-susceptible and low-level OFLX-resistant to Mycobacterium tuberculosis, OFLX concentration of 10 microg/ml is considered to be a better one.

To explore the difference of gene expression profile in tuberculosis patients.mRNA levels of pleural fluid and peripheral blood mononuclear cells (PBMC) in tuberculous pleurisy and lung cancer patients were compared by cDNA microarray. Paired mRNAs from fluid specimens of tuberculosis and lung cancer cases were labeled with different fluorochromes during cDNA probe synthesis in a reverse-transcription reaction. The signal intensity of each spot was measured by laser scanner and gene expression was quantified as the tubercle-to-normal fluorescence ratio (T:N ratio). The gene was defined as over expression when the T:N ratio was greater than 2.0 and under expression when the ratio was less than 0.5.Among 626 immunogenesis associated genes there were 53 differences, of which 31 (tnf-alpha, ig-lambda, il-17, il-17r, hla-dp, lcp1, tcralpha, tcrbeta, hsp75, cxcr4, fyb, hla-g, hla-a, il18bp, il-2r, lt-beta, il-8, ip-10, mcp-1, il-12, il-12r, il-10, canx, irf2, ifn-gamma, tlr, il-1, il-7, tlr, lsp-1, il-14)were higher and 22 (il-4, il-18, il-15, ifg-1, scya14, ablim, peci, ppid, hsf 2, actg2, maoa, ttid, gatm, tgfb3, insr, thbd, trap1, tcrgamma, tcrdelta, il-13r, il-11, igf1, a2m)were lower in tuberculous pleurisy than those in the control.The immunogenesis of tuberculosis involves multi-genetic expression changes, such as tnf-alpha, il-17, il-12, tcralpha, tcrbeta, hsp75, cxcr4, il-4, il-18, il-15 etc., the expression profile of which changed dramatically. The results provide new insight for understanding of the pathogenic mechanisms of tuberculosis and exploring new therapeutic strategies.

Hematopoiesis undergoes several migrations from yolk sac to liver and spleen, and finally bone marrow until the end of life. A number of investigations have demonstrated that the hematopoietic microenvironment plays very important role in this process. However, the exact mechanisms remain unknown. In order to systematically analyze and understand the role of hematopoietic microenvironment in the regulation and control of hematopoiesis, a microarray containing 588 complementary DNAs was used to compare the gene expressions between those in murine fetal liver and bone marrow cells. The results obtained from array hybridization were analyzed and reconfirmed by using bioinformatics and RT-PCR as well as Northern blot. The results showed that 65 and 131 genes were relatively high expressed in bone marrow and fetal liver cells respectively among 588 known genes in the array-membrane. According to the survey in the PubMed, 39 out of bone-marrow-expressed genes and 71 in fetal-liver-expressed genes were closely related to the hematopoiesis. Further reconfirmation by RT-PCR or Northern blot has demonstrated that CD18, CD44 an d PSGL-1 genes chosen for analysis were highly expressed in adult bone marrow, but unexpressed or lower expressed in fetal liver cells, resulting in high similarity to the array results. Moreover, the expressions of CD18 and CD44 in fetal liver were down-regulated with the increment of gestational age. In conclusion, the gene expressions in bone marrow and fetal liver cells are obviously different, some of the genes are down-regulated at the different stages of ontogeny. The different gene expression levels between bone marrow and fetal liver, especially those genes closely related to the hematopoiesis, may be the molecular basis for the explanation of why hematopoietic stem cells derived from different tissues have different characterizations as well as the differences from the beginning and terminating of fetal liver hematopoiesis, and why hematopoietic stem cells derived from fetal liver is tremendously difficult to be grafted in bone marrow.