Mesoscale modelling of miscible and immiscible multicomponent fluids.

A mesoscopic simulation method based on the integration of dissipative particle dynamics (DPD), smoothed particle hydrodynamics (SPH) and computational thermodynamics (CT) has been developed. The kinetic behaviours of miscible and immiscible fluids were investigated. The interaction force between multicomponent mesoscopic particles is derived from the system free energy. The diffusivity of the components in non-ideal solution is determined by the chemical potential. The proposed method provides convincing predictions to the effects of convection, diffusion and microscopic interaction on the non-equilibrium evolution of engineering fluids, and demonstrates a potential to simulate more complicated phenomena in materials processing.

Sensory gating in bilayer amorphous carbon memristors.

Multi-state amorphous carbon-based memory devices have been developed that exhibit both bipolar and unipolar resistive switching behaviour. These modes of operation were implemented independently to access multiple resistance states, enabling higher memory density than conventional binary non-volatile memory technologies. The switching characteristics have been further utilised to study synaptic computational functions that could be implemented in artificial neural networks. Notably, paired-pulse inhibition (PPI) is observed at bio-realistic timescales (<100 ms). Devices displaying this rich synaptic behaviour could function as robust stand-alone synapse-inspired memory or be applied as filters for specialised neuromorphic circuits and sensors.

[Collecting system percutaneous access using MR-assisted guidance: first human phantom experience].

Objective: Precise renal puncture is an essential but challenging step for successful percutaneous nephrolithotomy. We evaluated the efficiency of a novel real-time navigation system using Mixed Reality(MR) technology for human phantom kidney puncture. Methods: One human kidney phantom underwent MR-assisted percutaneous collecting system puncture. Two punctures were performed by each of 6 surgeons in the randomize selected upper, middle or lower calyces. Outcome measurements were the number of attempts for renal puncture, the time needed to evaluate the trajectory and to perform percutaneous puncture. Results: A total of 12 punctures were performed successfully using MR-Assisted Guidance. Median evaluation time and renal puncture time for the selected calyces was 13 (range 11 to 19) and 19 seconds (range 15 to 44), respectively. One or Two attempts were needed to achieve a successful renal puncture for all of the surgeons. Conclusions: The proposed MR-assisted guidance solution for renal collecting system puncture proved to be accurate, simple and quick. The inherent limitations of traditional X - ray and ultrasonic technology can be overcome.

Prognostic Factors for Survival in Node-Negative Gastric Cancer Patients Who Underwent Curative Resection.

BACKGROUND AND AIM: Lymph node involvement is the strongest prognostic factor for patients with gastric cancer; patients with node-negative gastric cancer present with better survival. However, some patients develop recurrent gastric cancer. The aim of this study was to review the clinicopathological characteristics and factors for prognosis in patients with node-negative gastric cancer who underwent curative resection. METHODS: Between January 2004 and December 2015, the clinicopathological characteristics of 302 patients with node-negative gastric cancer who underwent curative gastrectomy in our hospital were retrospectively analyzed. RESULTS: The 1-, 3-, and 5-year overall survival rates for patients with node-negative gastric cancer were 80.0%, 69.0%, and 63.0%, respectively. Univariate analysis showed that tumor size, histologic type, and depth of invasion had significant effects on survival (p < 0.05). Multivariate analysis showed that tumor size (hazard ratio: 1.83%, 95.0% confidence interval: 1.13-2.96, p = 0.014), histologic type (hazard ratio: 1.57%, 95.0% confidence interval: 1.01-2.44, p = 0.042), and depth of invasion (hazard ratio: 1.38%, 95.0% confidence interval: 1.14-1.67, p = 0.001) were independent prognostic factors. CONCLUSION: Tumor size, histologic type, and depth of invasion are important prognostic factors in patients with node-negative gastric cancer. These parameters should be considered to stratify patients for therapy and follow-up strategies.

[Effects on human peripheral erythrocytes of long-term occupational contact with chromate].

Objective: To investigate the effects on human peripheral blood erythrocytes of long-term occupational contact with chromate. Methods: A dynamic cohort study was conducted of chromate-exposed workers (343 cases) and non-chromate-exposed workers (73 cases) at a chromate production enterprise who were selected according to specific inclusion and exclusion criteria from 2010 to 2015. Personal information and chromate exposure information were obtained by questionnaire. A generalized estimating equation was employed to analyze the effects on human peripheral blood erythrocytes of long-term occupational contact with chromate, controlling for age, gender, smoking, alcohol consumption and body mass index. Results: The mean ages and working ages of those entering the cohort study were 36.67 ±6.78 and 38.47 ± 7.18, respectively, for the exposure group and 8.39 ± 6.02 and 12.86 ± 8.34, respectively, for the control group. The erythrocyte content [(4.73±0.46), (4.81±0.53), (4.41±0.45)]×1012/L in the peripheral blood in the chromate exposure group was lower than that [(4.76±0.42), (4.95±0.45), (4.47±0.39)]×1012/L in the control group for the years 2010, 2011, 2012 and 2014 (t values were 0.38, 1.96, 0.92 and 1.21; P values were 0.703, 0.051, 0.358 and 0.227, respectively). The correlations between the years 2010 and 2011, 2011 and 2012, 2012 and 2014, and 2014 and 2015 were 0.667, 0.464,-0.070 and 0.020, respectively (P<0.001). The RR for males and those that consumed alcohol were 0.661 (95% CI: 0.616-0.709) and 0.910 (95% CI: 0.811- 1.201), respectively. Compared with the control group, the risk of reduced erythrocyte levels in the peripheral blood was increased by 0.915 (95% CI: 0.852- 0.982) in the chromate-exposed group. Conclusions: The erythrocyte content of peripheral blood was reduced after long-term exposure to chromate. Maleness and alcohol consumption were factors that increased the risk of reduced peripheral blood erythrocytes in the chromate-exposed population.

CYP2C19 polymorphisms in acute coronary syndrome patients undergoing clopidogrel therapy in Zhengzhou population.

The goal of this study was to explore the polymorphisms of CYP2C19 (CYP2C19*2, CYP2C19*3) in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) on clopidogrel therapy in Zhengzhou city for guidance on clinical medication and reduction in the incidence of thromboembolic events. Two hundred and thirty-four ACS patients undergoing PCI were included in the study, including 171 males (average age = 64.13 ± 12 years) and 63 females (average age = 67.86 ± 10.20 years). Pyrosequencing analysis detected CYP2C19*2/*3 genotypes, which were divided into wild-type homozygous C/C, mutant heterozygous C/T, and mutant homozygous T/T. This study further explored the relationship between CYP2C19 polymorphisms and clopidogrel resistance in ACS patients. Gene frequencies of C/C, C/T, and T/T for CYP2C19*2 were 39.74, 50, and 10.26%, respectively, while the frequencies of C/C, C/T, and T/T for CYP2C19*3 were 94.02, 5.55, and 0.43%, respectively. According to platelet aggregation analysis, 203 cases normally responded to clopidogrel (86.8%) and 31 cases were clopidogrel resistant (13.2%). There was a correlation between gender and genotype distribution but none between age and genotype. In addition, patients with clopidogrel resistance were treated with ticagrelor antiplatelet therapy instead of clopidogrel, and only 1 case in all patients suffered thrombotic events during a 3-12 month follow-up. In conclusion, CYP2C19*2/*3 polymorphisms may be associated with clopidogrel resistance. Wild-type homozygote and single mutant heterozygote of CYP2C19*2/*3 can be given a normal dose of clopidogrel, while carriers with single mutant homozygote or double mutant heterozygote require ticagrelor antiplatelet therapy as an alternative.

Prognostic characteristics of duodenal gastrointestinal stromal tumours.

BACKGROUND: This study evaluated the clinical characteristics, surgical procedures and prognosis of duodenal gastrointestinal stromal tumours (GISTs). METHODS: Patients with a diagnosis of primary duodenal GIST treated between January 2000 and December 2012 were analysed. Patients with gastric and small intestinal GISTs were chosen as control groups according to the following parameters: age, tumour size, mitotic index and adjuvant imatinib therapy. Operative procedures for patients with duodenal GIST included pancreaticoduodenectomy or limited resection. Disease-free survival (DFS) was calculated using Kaplan-Meier analysis. RESULTS: Some 71 patients with duodenal, 71 with gastric and 70 with small intestinal GISTs were included in the study. DFS of patients with duodenal GIST was shorter than that of patients with gastric GIST (3-year DFS 84 versus 94 per cent; hazard ratio (HR) 3.67, 95 per cent c.i. 1.21 to 11.16; P = 0.014), but was similar to that of patients with small intestinal GIST (3-year DFS 84 versus 81 per cent; HR 0.75, 0.37 to 1.51; P = 0.491). Patients who underwent pancreaticoduodenectomy were older, and had larger tumours and a higher mitotic index than patients who had limited resection. The 3-year DFS was 93 per cent among patients who had limited resection compared with 64 per cent for those who underwent PD (HR 0.18, 0.06 to 0.59; P = 0.001). CONCLUSION: The prognosis of duodenal GISTs is similar to that of small intestinal GISTs.

The Co-film-thickness dependent lateral photoeffect in Co-SiO2-Si metal-oxide-semiconductor structures.

We report a transient lateral photoeffect (LPE) in thin metallic Co films deposited on n-type Si substrates with native SiO(2) surfaces. Under the nonuniform irradiation of a laser beam, the lateral phtovoltage (LPV) shows high sensitivity to the laser position in the metal film plane. This effect can be interpreted by the metal-semiconductor (MS) junction formed between metal and semiconductor. The LPV depends significantly on the thickness of Co film. The position sensitivity shows a peak value of 42.6 mV/mm for Co(2.8mn)-SiO(2)-Si and decreases greatly with the increase of the Co film thickness. We explain that by the shorting effect of the metallic film.

[Genetic diversity and differentiation of cultivated Fagoyrum tataricum populations from three counties in south Liangshan Automomous Prefecture of Yi Nationality, Sichuan, China].

Genetic diversity and differentiation among 8 cultivated populations of Fagopyrum tataricum from the counties of Jinyang, Leibo and Miyi in south Liangshan Autonomous Prefecture of Yi Nationality, Sichuan Province, China were investigated using allozyme electrophoresis. The allozymic diversity is roughly correlated with agrobiological features. The results suggest that genetic diversity of F. tataricum is quite high. The mean number of alleles per locus A is 1.8; the percentage of polymorphic loci P is 46.6%, and the mean observed heterozygosities Ho and the mean expected heterozygosities He are 0.187 and 0.218 respectively, the ratios of gene diversities of heterozygosities Fsr is 0.22, which indicates that there is 22 percent of genetic differentiation among populations, and suggests that for protecting genetic resources all the populations should be included in.

[Genetic diversity of Fagoyrum tataricum cultivated in north Liangshan Prefecture of Yi Nationality, Sichuan, China].

In the present paper is stated the accomplishment of the studies of 17 populations of cultivated Fagopyrum tataricum (L.) Gaertn. from the counties of Yuexi and Ganluo in North Liangshan Autonomous Prefecture of Yi Nationality, Sichuan Province, China by means of starch gel electrophoresis and cluster analysis of agrobiology features. Seven enzymes, and 15 loci were assessed. The result shows that the genetic diversity of F. tataricum within population is higher than in the South Prefecture and in species F. esculentum from other areas. The A, P, Ho and He are 1.9, 52.1%, 0.190 and 0.262 respectively. The FST is 0.199 which is close to the average level of wild plants. A conservation strategy of the genetic resource of F. tataricum is suggested. Two populations of local variety "Youchiqiao" have the richest genetic diversity, P = 60.0%, Ho = 0.260 and 0.301 and they should be protected particularly. Two populations of local variety "Xiaomiqiao" with higher genetic diversity, as well as three populations of local varieties of "Qiukuqiao", "Equkuqiao" and "Geluokuqiao" with special genetic position should be protected too.

Synthesis of a novel polyurethane co-polymer containing covalently attached RGD peptide.

The synthesis of a novel polyurethane block co-polymer containing a covalently attached, well-oriented RGD (Arg-Gly-Asp) peptide was explored. A poly(tetramethylene oxide) (PTMO)-based polyurethane was synthesized, and a bimolecular nucleophilic substitution reaction was then employed to incorporate ethyl carboxylate groups onto the polymer backbone (i.e. carboxylated polyurethane). Elemental analysis was used to determine the extent of carboxylation. The hexapeptide H-Gly-Arg-Gly-Asp-Ser-Tyr-OH was coupled to the carboxylated polyurethane via the formation of an amide bond. The attachment of the peptide was controlled by a protection-deprotection scheme. Nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopies were used to monitor the reactions. Sakaguchi assay and amino acid analysis confirmed that the RGD-containing peptide was successfully grafted onto the carboxylated polyurethane. This reaction scheme provides a new route for grafting end-linked, bioactive peptides onto polyurethanes.