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Structures, phase transitions, elastic properties and mechanical stability of thirteen TiO 2 polymorphs (fluorite, pyrite, rutile, anatase, hollandite, brookite, ramsdellite, columbite, cotunnite, modified fluorite, bronze, baddeleyite and hexagonal Fe 2 P-type phases) under pressure have been investigated using first-principles calculations. The optimal structural parameters and densities of thirteen TiO 2 polymorphs under zero or high pressure have been obtained and analyzed. The pressures of phase transitions and stability–instability transitions have been predicted, particularly the latter has been systematically discussed using the modified Born stability conditions.

Hepatocellular carcinoma with bile duct tumor thrombus (BDTT) is a malignant disease. The most commonly used diagnosis methods for BDTT are MRCP/ERCP, ultrasonic diagnosis or CT scan. However, BDTT is often misdiagnosed as other bile duct diseases, such as extrahepatic cholangiocarcinoma (EHCC), choledochal cyst (Cyst) and common bile duct stone (Stone). Diagnostic methods, which are more accurate and less destructive, are urgently needed. In this paper, we analyzed the small molecule metabolites in the serum of BDTT, Stone, Cyst and EHCC patients and normal people using untargeted GC-MS, and identified 21 metabolites that show different levels among different samples. Using targeted UHPLC-QQQ-MS analysis, we found that several metabolites are significantly changed. ROC curve analysis revealed two metabolites, L-citrulline and D-aspartic acid, as potential biomarkers that can distinguish BDTT from other bile duct diseases.

Static state security analysis (SSSA) is one of the most important computations to check whether a power system is in normal and secure operating state. It is a challenge to satisfy real-time requirements with CPU-based concurrent methods due to the intensive computations. A sensitivity analysis-based method with Graphics processing unit (GPU) is proposed for power systems, which can reduce calculation time by 40% compared to the execution on a 4-core CPU. The proposed method involves load flow analysis and sensitivity analysis. In load flow analysis, a multifrontal method for sparse LU factorization is explored on GPU through dynamic frontal task scheduling between CPU and GPU. The varying matrix operations during sensitivity analysis on GPU are highly optimized in this study. The results of performance evaluations show that the proposed GPU-based SSSA with optimized matrix operations can achieve a significant reduction in computation time.

Background: Nocturnal enuresis (NE) is not an uncommon disease in children, and the prevalence and clinical features have regional variations, but the relative data is scanty in southern China. The aim of this study is to establish the prevalence of NE and predictive factors in a large population of South Chinese children. Methods: From December 2013 to July 2014, 15547 questionnaires were distributed to parents and children of 14 primary schools in Guangzhou and Zhongshan. Results: Correctly completed response rate was 74.6%. Overall NE prevalence was 10.9% (1260/11599). NE was significantly more frequent in boys (P

Rolling circle amplification (RCA) of DNA is a sensitive and cost effective method for the rapid identification of pathogens without the need for sequencing. In this study, a surface plasmon resonance DNA biosensor based on RCA with a gold (Au) nanoparticle surface was established for isothermal identification of DNA. The probes included a specific padlock probe, a capture probe (CP), which is bound to biotin, and an Au nanoparticle-modified probe, which hybridizes with the RCA products. The CP was assembled on gold nanoparticles to increase its ability to bind and hybridize. The linear padlock probe, which was designed to circularize by ligation upon recognition of the bacterial pathogen-specific sequence in 16S rDNA, hybridizes to fully complementary sequences within the CP. Upon recognition, each target gene DNA is distinguished by localization onto the corresponding channel on the chip surface. Then, the immobilized CPs act as primers to begin the in situ solid-phase RCA reaction, which produces long single-stranded DNA. The RCA products fixed on the chip surface cause significant surface plasmon resonance angle changes. We demonstrated that six different bacterial pathogens can be identified simultaneously and that 0.5 pM of synthetic oligonucleotides and 0.5 pg μl(-1) of genomic DNA from clinical samples can be detected by this method with low background signals. Therefore, the multiplex diagnostic method provides a highly sensitive and specific approach for the rapid identification of positive samples.

The response to epidermal growth factor receptor (EGFR)-targeted therapy in metastatic colorectal cancer (mCRC) is variable because of intra-tumor heterogeneity at the genetic level, and consequently, it is important to develop sensitive and selective assays to predict patient responses to therapy. Low-abundance BRAF V600E mutations are associated with poor response to treatment with EGFR inhibitors. We developed a method for the detection of BRAF V600E mutations in mCRC using real-time wild-type blocking PCR (WTB-PCR), in which a chimera composed of locked nucleic acids and DNA is incorporated to amplify the mutant allele at high efficiency while simultaneously inhibiting the amplification of wild-type alleles. Mixing experiments showed that this method is exquisitely sensitive, with detection of the mutated allele at a mutant/wild-type ratio of 1:10,000. To demonstrate the applicability of this approach for mCRC patients, we assessed the V600E mutations in 50 clinical cases of mCRC by real-time WTB-PCR. The percentage of patients with V600E mutation as determined by WTB-PCR (16%, 8/50) was higher than by traditional PCR (10%, 5/50), suggesting an increased sensitivity for WTB-PCR. By calculating the ΔC q for real-time traditional PCR, which amplifies all BRAF alleles, versus WTB-PCR, which selectively amplifies mutant BRAF, we demonstrated that among the V600E-positive mCRC patient samples, the percentage of BRAF DNA with the V600E mutation ranged from 0.05 to 52.32%. In conclusion, WTB-PCR provides a rapid, simple, and low-cost method to detect trace amounts of mutated BRAF V600E gene.

Initial disturbance is the chief factor that affects missile launch accuracy and divergence while using orientation devices could reduce it effectively. In this paper, adapter combined with guide rail will be mainly studied. Modeling and simulation for missile systems will be done by virtual prototyping technology, focusing on deflection, pitch angle, and pitch angular velocity and so on to analysis initial disturbance. Results show that by mean of adapter combined with guide rail initial disturbance could be greatly reduced and launch accuracy has been improved.

In this letter, we present an extensive study of the linearly forced isotropic turbulence. By using analytical method, we identify two parametric choices, of which they seem to be new as far as our knowledge goes. We prove that the underlying nonlinear dynamical system for linearly forced isotropic turbulence is the general case of a cubic Lienard equation with linear damping. We also discuss a Fokker-Planck approach to this new dynamical system,which is bistable and exhibits two asymmetric and asymptotically stable stationary probability densities., 7 pages, 1 figure

Purpose To identify prognostic predictors for overall survival of patients with hilar cholangiocarcinoma of Bismuth type III and IV (HCBT34), and to determine survival benefit and safety of total caudate lobectomy (TCL) in a Chinese centre. Methods From January 2001 to December 2010, 171 patients with the diagnosis of HCBT34, who underwent a potentially curative resection, were included in this study. Cox proportional hazards regression models were used to determine the association between possible prognostic variables and survival time. Curative resectability rate, morbidity and mortality were investigated also. Results Resection with TCL was significantly associated with more opportunity to achieve curative resection ( p p = 0.39) and mortality ( p = 0.67). Cox regression analysis demonstrated positive resection margins [Relative Risk (RR) 3.6, 95% CI 3.5–3.7], not well differentiation (RR 2.9, 95% CI 2.7–3.1), higher preoperative serum peak CA19-9 level (RR 1.6, 95% CI 1.5–1.7) and regional lymph nodes involvement (RR 1.5, 95% CI 1.4–1.6) as independent adverse prognostic variables. Conclusions Resection with TCL offers a long-term survival opportunity for HCBT34, with high curative resectability rates and an acceptable safety profile.

Aims and background As a powerful technique allowing analysis of large numbers of cells, fluorescence-activated cell sorting (FACS) is used more and more widely. For FACS analysis, adherent cells are usually detached by trypsinization, followed by centrifugation and resuspension. However, trypsinization can cut off some receptors from the cell surface like fine scissors, which will affect the accuracy of FACS results. Though non-enzymatic methods such as citric saline buffer have been used to determine cell surface receptors, how much of the receptors is cut off by trypsinization has been rarely studied. This work aimed to investigate whether different methods of detaching adherent cells could affect the detection of cell surface receptors. Methods Human hepatocellular carcinoma cell lines (HepG2, Huh7 and Hep3B) were detached enzymatically with trypsin-EDTA solution or non-enzymatically with citric saline buffer, and then the receptors of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) were detected by FACS analysis. Cell viability, cell cycle and apoptosis (sub-G1 fraction detected by FACS) of the trypsin-EDTA group and citric saline buffer group were also studied. Results Different methods of detaching adherent cells could significantly affect the detection of TRAIL receptors. Compared to the conventional trypsin-EDTA group, the non-enzymatic group showed a 3.42-fold increase in the mean fluorescence intensity index of DcR HepG2 and a 1.25-fold increase in DR Huh 7 (P Conclusions Citric saline buffer might be recommended as the first choice to detach adherent cells for FACS analysis of cell surface receptors.

In order to improve the overall performance of the engine cooling system, make the engine work in a stable and suitable thermal condition, a fuzzy controller for the engine cooling system was designed, then the cooling control model was established in Simulink, and the engine cooling system model of a diesel engine was built in GT-cool. Simulation computation was taken on the coupling of the two models. The results indicate that fuzzy control has visible effect for the improvement of the cooling system.