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This paper proposes a novel intelligent optimal control strategy for crawler vehicles with semi-active suspension. The proposed control strategy aims at improving vehicle ride comfort by addressing contradictory suspension properties requirements of ride comfort and handling stability simultaneously. After establishing seven degrees of freedom dynamic model of the crawler vehicle, a comprehensive evaluation index is developed to trade off among various vehicle performances, which include ride comfort, damper thermal reliability, elastic element fatigue and handling stability. Then, using modified staged continuous tabu search (MSCTS) algorithm, the optimal control efforts of semi-active suspension, damping ratios, are determined by minimizing the cost function defined by the comprehensive evaluation index. Demonstrated by simulations with triangle convex block and random ground roughness excitations, MSCTS control strategy can successfully improve ride comfort performance and achieve the optimal comprehensive performance as well. [ABSTRACT FROM AUTHOR]

Unbound, single-stranded RNA can be digested by RNase (A or T1) to ribonucleotides, whereas double-stranded RNA is not digested by RNase. Based on this principle, the RNase Protection Assay (RPA) is used to validate chimeric RNAs. Importantly, this assay does not employ reverse transcription (RT), thus avoiding potential false-positive results which could occur during RT such as template-switching. We first generate RNA probes with 32 phosphate (P) or biotin that are complementary to the predicted nucleotide sequence of the chimeric RNA, then hybridize them to RNA samples. The labeled RNA probes can bind specifically with the target chimeric RNA in order to form double-stranded RNA. This newly formed RNA is resistant to digestion by RNase and therefore can be identified by high-resolution, denaturing polyacrylamide gel electrophoresis.

Background and Objective: Epidermal growth factor receptor (EGFR) and KRAS status were particularly critical for the choice of first-line targeted therapy of non-small cell lung cancer (NSCLC), while the primary tumor and metastases might be different in the EGFR and KRAS gene status. The aim of this pooled analysis is to compare EGFR and KRAS status in matching primary NSCLC and metastases and further to guide clinical practice., Methods: Systematic computerized searches of the Pubmed and Medline databases (up to May 10, 2010) meeting specified search criteria were performed, followed by a further screening according to inclusive and exclusive criteria., Results: Fourteen articles were selected into the final meta-analysis with paired primary and metastatic cases of 598. Expression level of EGFR protein and mutation frequency of KRAS gene in primary tumors were higher than that in metastases, relative risk (RR)=1.13 (95%CI: 0.98-1.31, P=0.09) and RR=1.39 (95%CI: 0.95-2.03, P=0.09), respectively. EGFR gene copy number in metastases was higher than that in primary tumor, RR=0.74 (95%CI: 0.53-1.02, P=0.06). There was no statistically significant difference of EGFR mutation frequency in primary tumors and metastases (P=0.31). The discordant rate in primary and metastases was 17.09% for EGFR mutation, 27.07% for EGFR amplification, 27.84% for EGFR protein expression and 25.91% for KRAS mutation., Conclusions: The systematic analysis showed that the EGFR mutation status in primary lung cancer and corresponding metastases was more stable than KRAS gene. KRAS mutation in primary lung cancerous foci seems to better reflect systemically cancerous genetic characteristics of KRAS gene. Determination of KRAS gene status based merely on metastatic foci might lead to more resistant selections of EGFR tyrosine kinase inhibitor (TKI) therapy. Combined detection of EGFR and KRAS mutation from primary NSCLC foci might serve as a better predictive biomarker for anti-EGFR targeted therapy.