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Spray painting robots equipped with air spray guns have been widely used in the painting industry. In view of the low efficiency of single-nozzle air spray guns when spraying large targets, a new double-nozzle air spray gun structure was designed in this paper based on the Coanda effect of double jets. Firstly, a 3-D physical model of the double-nozzle air spray gun was built in Solidworks, in which unstructured grids were generated for the computational domain by ICEM. Secondly, the spray painting process was numerically modeled with the help of the computational fluid dynamics (CFD) software ANSYS-Fluent 16.0. The two-phase spray flow was calculated by coupling a discrete phase model (DPM) and the Taylor analogy breakup (TAB) method. The TAB model was applied to predict the secondary break-up. The DPM model was applied to predict the droplet trajectories. The geometry of an air spray gun has a significant influence on the spray flow field characteristics. The influence of the air spray gun geometry on the interference spray flow field characteristics and coating film thickness distribution were investigated by changing the values of the distance between the centers of the two paint holes (L) and the angle between the axes of the two paint holes (&theta, ). Numerical results show that the smaller L and &theta, are, the stronger the interference effect between the two jets, while the more concentrated the paint is in the central region of the target surface, the easier it is for overspray to occur. With increasing L and &theta, the interference effect gradually decreased and the extension distance of the coating film along the x-axis gradually increased. However, if L and &theta, are too large, the interference effect will become too weak and the shape of the coating film will become a concave, with more paint on both side regions and less paint in the central region, which will cause an uneven coating film. From the simulation results, it can be concluded that a more uniform coating film can be obtained when L = 30 mm and &theta, = 10&deg, The effective coating width of the double-nozzle air spray gun was increased by 85.7% compared with the single-nozzle air spray gun, which improved the spraying efficiency.

For establishing rational farming mechanism, it is essential to know the relative contribution of different geological background and anthropogenic activities to trace elements in agricultural soil. In this paper, 282 surface soil samples were collected based on the different geological background. Five harmful trace elements (As, Cd, Cr, Hg and Pb) were analyzed. The results indicated most of trace elements contents were far beyond the threshold of uncultivated soil background, which indicate anthropogenic input strongly influenced on trace elements in agricultural soil. In addition, correlation analysis showed trace element contents exhibited high relationships with soil pH, C/N and physical clay (

To investigate the effect of occlusal reconstruction on blood flow velocity and cerebral oxygen saturation in patients with malocclusion.Thirty-three patients with malocclusion treated with occlusal reconstruction in Department of Stomatology, Medical School of Huzhou Normal College from Feb 2011 to Oct 2013 were enrolled in the study. The systolic peak flow velocity (vs), end-diastolic peak flow (vd) , mean peak flow velocity (vm) of middle cerebral artery and the oxygen saturation (rScO2) in the brain were detected at rest or chewing status by using transcranial Doppler color ultrasonography and near-infrared spectroscopy, respectively.In rest state, vm was significantly increased on 3 months after treatment, while vs and vd were significantly increased on 6 months after treatment and rScO2 were increased on 12 months after treatment (P0.05). In chewing state, vs, vm, and rScO2 were increased on 3 months after treatment, and vd was increased on 6 months after treatment (P0.05).Occlusal reconstruction can increase blood flow velocity of middle cerebral artery and cerebral oxygen saturation and improve oxygen supply of the brain in patients with malocclusion.

Migration of a bullet to a distant part of the body after a gunshot is rarely observed in the clinical setting, and migration to the heart is even rarer. There are usually no clear symptoms or signs from migration of a bullet. The bullet can be easily missed and sometimes identified in a review examination. A case of bullet migration to the heart 2 months after a gunshot to the left knee was reported.

Amino acids Tyr14 and Arg22 in trichosanthin are residues on helix A1 close to the active-site cleft. They are invariant in various type-I and type-II ribosome-inactivating proteins. In this study, Tyr14 was changed to Phe and Arg22 to Lys and Leu. Modified proteins were purified, and activities compared by assaying their median inhibitory concentration (ID50) on a rabbit-reticulocyte-lysate protein-synthesis system. While the ID50 of wild-type trichosanthin was 0.02 nM, those for [Phe14], [Lys22], [Leu22] and [Phe14, Leu22]trichosanthin were 0.10, 0.03, 0.25 and 0.15 nM, respectively. Therefore, compared with Tyr14, Arg22 appears to play a more important role in trichosanthin. Structural studies on [Leu22]tricho-santhin showed that two water molecules occupy the space left by the side chain of Arg22, and hydrogen bonds exist between these water molecules and nearby residues to retain the conformation. The use of intermolecular rather than intramolecular hydrogen bonds may have an adverse effect on stability or folding of the protein and results in a mild decrease in activity.

Background and purposeEarly haematoma expansion is determinative in predicting outcome of intracerebral haemorrhage (ICH) patients. The aims of this study are to develop a novel prediction model for haematoma expansion by applying deep learning model and validate its prediction accuracy.MethodsData of this study were obtained from a prospectively enrolled cohort of patients with primary supratentorial ICH from our centre. We developed a deep learning model to predict haematoma expansion and compared its performance with conventional non-contrast CT (NCCT) markers. To evaluate the predictability of this model, it was also compared with a logistic regression model based on haematoma volume or the BAT score.ResultsA total of 266 patients were finally included for analysis, and 74 (27.8%) of them experienced early haematoma expansion. The deep learning model exhibited highest C statistic as 0.80, compared with 0.64, 0.65, 0.51, 0.58 and 0.55 for hypodensities, black hole sign, blend sign, fluid level and irregular shape, respectively. While the C statistics for swirl sign (0.70; p=0.211) and heterogenous density (0.70; p=0.141) were not significantly higher than that of the deep learning model. Moreover, the predictive value for the deep learning model was significantly superior to that of the logistic model of haematoma volume (0.62; p=0.042) and the BAT score (0.65; p=0.042).ConclusionsCompared with the conventional NCCT markers and BAT predictive model, the deep learning algorithm showed superiority for predicting early haematoma expansion in ICH patients.