Research on Practical Teaching of Railway Engineering Specialty Based on Temperature Test of Rubber Sleepers

Experimental teaching plays an important role in cultivating college students' innovative ability. This paper takes the practical teaching of the temperature test of the new rubber sleeper as an example to analyze the current situation and problems of the practical teaching of railway engineering. The specific measures of the new system of practical teaching of railway engineering are put forward: Build a practical teaching curriculum system, improve the practical teaching evaluation mechanism, and promote the sharing of school-enterprise resources, so as to cultivate outstanding railway engineering talents with engineering ability and innovative spirit

Development and verification of lead-bismuth cooled fast reactor calculation code system Mosasaur

Lead-bismuth cooled fast reactor calculation code system named MOSASAUR has been developed to meet the simulation requirements from LBFR engineering design. An overview of MOSASAUR developments is provided in this paper, four main functional modules and their models are introduced: cross-sections generation module, flux spectrum correction module, core simulation module and sensitivity and uncertainty analysis module. Verification and validation results of numerical benchmark calculations, code-to-code comparisons with the Monte-Carlo code and critical experimental calculations shown in this paper prove the capabilities of MOSASAUR in dealing with lead-bismuth cooled fast reactor analysis problems with good performances. Numerical results demonstrate that compared with the Monte-Carlo code, the relative errors of eigenvalues are smaller than 350pcm when the calculations were carried out with the same nuclear data file. Compared with the measured values, the errors will increase due to the simulation details and the measurement accuracy

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Breast Cancer Metastasis Suppressor 1 Regulates Hepatocellular Carcinoma Cell Apoptosis via Suppressing Osteopontin Expression

<div><p>Breast cancer metastasis suppressor 1 (BRMS1) was originally identified as an active metastasis suppressor in human breast cancer. Loss of BRMS1 expression correlates with tumor progression, and BRMS1 suppresses several steps required for tumor metastasis. However, the role of BRMS1 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that the expression level of BRMS1 was significantly down-regulated in HCC tissues. Expression of BRMS1 in SK-Hep1 cells did not affect cell growth under normal culture conditions, but sensitized cells to apoptosis induced by serum deprivation or anoikis. Consistently, knockdown of endogenous BRMS1 expression in Hep3B cells suppressed cell apoptosis. We identified that BRMS1 suppresses osteopontin (OPN) expression in HCC cells and that there is a negative correlation between <em>BRMS1</em> and <em>OPN</em> mRNA expression in HCC tissues. Moreover, knockdown of endogenous OPN expression reversed the anti-apoptosis effect achieved by knockdown of BRMS1. Taken together, our results show that BRMS1 sensitizes HCC cells to apoptosis through suppressing OPN expression, suggesting a potential role of BRMS1 in regulating HCC apoptosis and metastasis.</p> </div

BRMS1 suppressed OPN expression in HCC cells.

<p>(A) Endogenous OPN expression in SK-Hep1 cells transfected with a gradient of doses of exogenous BRMS1 (ng/well) was investigated by western blotting using an anti-OPN antibody. Whole cell lysates (WCL) and conditioned medium (CM) were subjected to anti-OPN immunoblotting to detect intracellular OPN and secreted OPN, respectively. β-actin was used as a loading control. (B) Intracellular OPN and secreted OPN levels in SK-Hep1 stable cell lines were investigated by western blotting. (C) <i>OPN</i> mRNA expression levels in SK-Hep1 stable lines were investigated through qRT-PCR. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042976#s2" target="_blank">Results</a> are representative of independent experiments with consistent results. (D) Endogenous <i>BRMS1</i> (black box) and <i>OPN</i> (gray box) mRNA expression levels were analyzed in 33 HCC tumor tissues (No.1–33) and corresponding non-tumorous tissues through qRT-PCR and the 2^−ΔΔCt method as mentioned in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042976#s4" target="_blank">Materials and Methods</a>. A positive log₂-transformed fold change value indicates higher expression levels in tumorous specimens compared to the non-tumorous specimens while a negative value indicates decreased relative mRNA levels.</p

Effects of BRMS1 expression on SK-Hep1 cells.

<p>(A) A colony formation assay was performed on cells transiently transfected with vector control or a recombinant BRMS1 plasmid. Representative pictures are shown in the left panel and relative colony numbers are indicated in the histogram in the right panel. (B) Relative exogenous <i>BRMS1</i> mRNA expression in SK-Hep1 stable cell lines was quantifiedthrough qRT-PCR by normalization to <i>ACTB</i>. (C) Exogenous BRMS1 protein expression in stable cell lines was detected through western blotting analysis using anti-GFP and anti-BRMS1 antibodies. β-actin was used as a loading control. (D) Cell growth curves of mixed stable cell lines under normal culture conditions were calculated using the CCK8 assay. Values were indicated as mean ± SD, n = 5. (E) Cell growth curve of mixed stable lines under serum starvation. Values were indicated as mean ± SD, n = 5. (F) Cell apoptosis levels were determined by sub-G1 analysis using flow cytometry. Representative pictures are given and apoptotic cell ratios were presented as mean ± SD, n = 3. (G) Caspase 8, caspase 9 and PARP cleavage was investigated in stable cell lines undergoing anoikis through western blotting analysis using specific antibodies.</p

BRMS1 expression pattern in HCC tissues and cells.

<p>(A) The expression level of BRMS1 was analyzed in HCC tissues (T) and corresponding non-tumorous tissues (N) by western blotting analysis using an anti-BRMS1 antibody. β-actin was used as a loading control. (B) The expression level of BRMS1 in different HCC cells was also investigated through western blotting analysis.</p

Relationship between BRMS1 and OPN mRNA expression in HCC specimens.

<p>The relationship between <i>BRMS1</i> mRNA expression level and <i>OPN</i> mRNA expression level in 33 paired HCC tissues was analyzed by Fisher's exact test.</p

Effects of additional OPN knockdown on Hep3B cells.

<p>(A) Relative BRMS1 and OPN expressions in Hep3B cells infected with LNS, LS1 and LS1+LO were analyzed by western blotting. Representative pictures are shown and densitometric values are given in mean ± SD, n = 3. Both WCL and CM of cells were subjected to anti-OPN immunoblotting. (B) Relative <i>BRMS1</i> and <i>OPN</i> mRNA expressions in Hep3B cells were analyzed through qRT-PCR. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042976#s2" target="_blank">Results</a> are representative of independent experiments with consistent results. Cell growth curves of Hep3B infected with LNS, LS1 and LS1+LO were recorded under normal culture conditions (C) and serum deprivation (D). Values are indicated as mean ± SD, n = 5. (E) Cell apoptosis levels of lentivirus-infected cells were determined through sub-G1 analysis. Representative flow cytometric pictures are given and apoptotic cell ratios are presented as mean ± SD, n = 3. (F) Caspase 8, caspase 9 and PARP cleavage was detected in indicated Hep3B cell lines undergoing anoikis.</p