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A 32-year-old man with endogenous hyperinsulinemic hypoglycemia was clinically diagnosed with an insulinoma. Conventional imaging result was negative, and a previous exploratory laparotomy with distal pancreatectomy failed to detect the tumor. Ga-exendin-4 PET/CT showed a lesion with intense radioactivity in the head of the pancreas suggestive of an insulinoma, and endoscopic ultrasound-guided ethanol ablation was performed. Postablation evaluation with Ga-exendin-4 PET/CT showed markedly decreased radioactivity of the tumor. The symptoms and blood glucose monitoring also suggested partial response of the insulinoma.

An upwind finite volume method on curvilinear grids has been developed to simulate two-dimensional, inviscid, incompressible free surface flows. In this method, the level set method is used to capture the interface. The level set equation and the flow governing equations (Euler equations) are not solved separately, but incorporated into a system equation. The artificial compressibility method is adopted to solve the resulting hyperbolic equations. The MUSCL-Roe scheme, which is widely used in compressible flow computations, is employed to discretize the convective terms. A fully implicit dual-time stepping method with a highly efficient LU-SSOR algorithm as sub-iteration scheme is applied to advance the solution in time. In the present study, a re-initialization method on curvilinear grids for level set function is presented. An example of re-initialization for level set function on curvilinear grids is demonstrated and the resulting level set function is in good agreement with the exact distance function. Numerical results of a sloshing tank problem and a broken dam problem agree well with the theoretical and experimental data, respectively. The free surface flow over a submerged hydrofoil is also simulated using overset grids to demonstrate the capability of dealing with complex geometry. At last, the simulation of droplet splash problem is performed to show the ability of the present method in handling topological changes of the free surface.

A structured overset-grids method with enhanced implicit hole-cutting has been developed to simulate the flow around aircraft configurations, especially high-lift configurations. The current research uses the implicit hole-cutting method to improve the automation of domain connectivity and optimize the overlapping areas. Some enhancements for the original implicit hole-cutting method are proposed to make it more effective. Furthermore, a simple method for calculating the force on the overlapping solid surfaces is also presented. Jameson's second-order finite volume method is utilized to solve the Navier-Stokes equations. A wing-body configuration and two high-lift configurations are numerically tested and the numerical results are compared with the experimental data.

IntroductionColonoscopy is the reference method in screening and diagnosis of colorectal neoplasm, but its efficacy is closely related to the quality of bowel preparation. Poor patient compliance is a major risk factor for inadequate bowel preparation likely due to poor patient education. Such an education is usually provided via either oral or written instructions by clinicians. However, multiple education methods, such as smartphone applications, have been proved useful in aiding patients through bowel preparation. Also, it was reported that a large proportion of patients feel anxious before colonoscopy. Virtual reality (VR) is a novel method to educate patients and provides them with an immersive experience. Theoretically, it can make patients better prepared for bowel preparation and colonoscopy. However, no prospective studies have assessed the role of this novel technology in patient education before colonoscopy. We hypothesise that VR videos can improve bowel preparation quality and reduce pre-procedure anxiety.Methods/designThe trial is a prospective, randomised, single-blinded, single-centre trial. Outpatients who are scheduled to undergo colonoscopy for screening or diagnostic purposes for the first time will be randomised to receive either the conventional patient education or the conventional methods plus VR videos, and 322 patients will be enrolled from the Peking Union Medical College Hospital. The primary endpoint is the quality of bowel preparation, measured by the Boston bowel preparation score. Secondary endpoints include polyp detection rate, adenoma detection rate, cecal intubation rate, patient compliance to complete bowel cleansing, withdrawal time, pre-procedure anxiety, overall satisfaction and willingness for the next colonoscopy.Ethics and disseminationThe study has been approved by the institutional review board of the Peking Union Medical College Hospital (No. ZS-1647). The results of this trial will be published in an open-access way and disseminated among gastrointestinal physicians and endoscopists.Trial registration numberNCT03667911

Human cytomegalovirus (CMV) is a herpesvirus, which establishes lifelong latency after primary infection and leads to severe disease in immunocompromised patients. However, CMV infection in immunocompetent patients is usually asymptomatic and severe organ damage is rarely reported. We report a case of severe CMV hepatitis in an immunocompetent patient presenting with cholestasis, portal hypertension-related ascites and pancytopenia. The patient was asymptomatic with normal liver function and negative CMV DNA after two weeks of antiviral therapy. This case is an example of a common infection with an uncommon presentation, and suggests that testing for CMV should be carried out, even in patients with normal immune status, presenting with severe liver damage or cholestasis.

The integer linear programming is an NP-complete problem. In this paper, a detailed discussion is given of DNA algorithms for the DNA solution of the integer linear programming.

In this paper, the mechanism of Hg1−xCdxTe/Si heterojunction grown by HWE (Hot Well Epitaxy) was studied. Opitical characterizations were shown with FTIR, the composition x = 0.39 was deduced by using MIR transmittance, the absorbing peak at 319.4 cm−1 was measured by FIR transmittance, 319.4 cm−1 confirmed the existence of Si–Te bond of at Si/HgCdTe interfacial layer. The I-V characteristics at both room temperature and 77 K of HgCdTe (n-type)/Si (p-type) heterojunction show that the good p-n heterojunction properties was obtained by using HWE. XRD study confirmed the formation of (111) oriented HgCdTe on (211) Si. Morphology of a cross section observed using EPMA indicates the columnar growth of HgCdTe. An analysis of interfcial layer by EPMA indicated presence of three layers composed of Si + Te, Si + Te + Hg and Si + Te + Cd + Hg. Among them, the most important one is the first layer. The problem of lattice mismatch and the difference of thermal expansion coefficient between Si and CdTe or HgTe may be improved by formation of Si–Te stable chemical bond through bybridization orbital bonding between Si and Te. The second and third layers are formed by evaporation-interdiffusion. Formation of the whole interfacial layer provides the appetency for the growth of (111) Hg1−xCdxTe epilayer on (211) Si substrate.

New applications of confocal laser endomicroscopy (CLE) have been developed, such as needle-based CLE (nCLE) for pancreatic masses, pancreatic cystic tumors, and lymph nodes. nCLE is feasible during endoscopic ultrasound (EUS) examination, and preliminary results are very encouraging and suggest this technology may be used in future as a useful adjunct in cases of inconclusive EUS-guided fine-needle aspiration. The aim of this paper is to give an update in this new technology and to define its place in the diagnosis of pancreatic masses and mediastinal diseases.

ACCURATE simulation of the viscous flow around a helicopter rotor is still a challenging problem. To predict the blade loading accurately, the numerical method must have a capability to capture the vortical wake generated from the rotor blade tip precisely, which significantly affects the aerodynamic performance of the rotor. Therefore, both the numerical scheme with low numerical dissipation and sufficient dense mesh far away from the blade surface are required for rotor computations to simulate the tip vortex with minimal distortion. Furthermore, for a hovering case, a large numerical integration time is needed for the capture of the fully developed vortical wake [1]. In addition, the existence of incompressible flow near the root will also make the convergence slow. Compared with fixed-wing computations, hovering rotor computations not only require more accurate numerical scheme but also will take much more run time to converge. During the past two decades many numerical methods [2–7] have been developed to simulate the viscous flow around a hovering rotor. The methods [2,3] with the single-block structured grid suffer from the grid-quality problem, because the mesh must be stretched and skewed to cover the complete computational domain and to match the periodic boundary condition. To avoid this problem, the chimera technique [4–7] suggested by Benek et al. [8] was introduced into hovering rotor computations. To capture the tip vortex without unphysical distortion and predict the blade loading accurately, some high-order schemes and vortex-adapted chimera methods [6,7] were presented. Although significant advances in the accurate simulation of the tip vortex have been made with these advanced methods, the large computation cost and the low robustness, as well as the complexity make them far away from engineering applications. As mentioned above, hovering rotor computations, especially the computations with high-order methods, require more run time to converge than their fixed-wing counterparts. A few attempts [1,9,10] have been made to use multigrid methods to accelerate the convergence of hovering rotor calculations. Up to now, there is few works concerning the multigrid method for the viscous flow computation about a hovering rotor based on overset grids. The main objective of the present study is to develop an efficient multigrid algorithm coupled with chimera grids for Navier–Stokes computations about a hovering rotor. It should be mentioned that the experience of this work can be extended to accelerate the computation about a rotor in forward flight using moving overset grids,which is themainmotivation of this research. Furthermore, this experience can also be the basis of the future multigrid computation using high-order methods and chimera grids for rotor flows.

Uveitis is an autoimmune disease of the eye that refers to a number of intraocular inflammatory conditions. We identified three rare cases of T cell lymphoma diagnosed following an initial presentation of uveitis. This study summarized the clinical features of these rare cases and evaluated the association between uveitis and lymphoma. We analyzed the etiology of uveitis diagnosed in the Department of Pediatrics and Internal Medicine at our hospital. Five patients were diagnosed with uveitis and lymphoma. We present case reports of three patients who were diagnosed with T cell lymphoma following an initial presentation of uveitis. From January 1985 to June 2013, there were 80 cases of uveitis and 1,900 cases of lymphoma in the Department of Pediatrics and Internal Medicine at our hospital. We found five patients that were diagnosed with uveitis and lymphoma; of these, three had a definite pathologic diagnosis of T cell lymphoma. The odds ratio (OR) was 6.08 (95 % confidence interval [CI] of 1.93-14.94, P = 0.002) for the five patients with uveitis and lymphoma, suggesting a significant association. The OR was 3.67 (95 % CI of 1.16-11.65, P = 0.053) for the three patients with uveitis and T cell lymphoma. Uveitis may be a rare presentation of malignant disease, such as lymphoma. Ophthalmologists and general practitioners should be familiar with the differential diagnosis of uveitis.

(99m)Tc-3PRGD2 is a new SPECT tracer targeting integrin α(V)β(3) receptor for detecting tumors, imaging angiogenesis, and evaluating tumor response to therapy. A multicenter study was designed to investigate the efficacy of (99m)Tc-3PRGD2 for the evaluation of patients with lung cancer.Seventy patients (51 men, 19 women; mean age ± SD, 63 ± 9 y) with a suspected lung lesion and for whom definite pathologic diagnosis was finally obtained (malignant, n = 58; benign, n = 12) were recruited from 6 centers. Whole-body planar scanning and chest SPECT were performed at 1 and 4 h, respectively, after intravenous injection of 11.1 MBq/kg (0.3 mCi/kg) of (99m)Tc-3PRGD2. The images were read in consensus by 6 experienced nuclear medicine physicians masked to the source, history, and pathologic diagnosis. The tumor-to-background (T/B) ratios were calculated for semiquantitative analysis. A Student t test was used for statistical analysis, and a P value less than 0.05 was considered significant.With low (99m)Tc-3PRGD2 background in the lungs and mediastinum, most lung malignancies were prominent on the 1-h images (T/B ratio, 1.65 ± 0.47 for the planar imaging and 2.78 ± 1.52 for SPECT). The T/B ratios were significantly lower in the benign lesions (P0.05). The sensitivity was 88% for semiquantitative analysis and could reach 93%-97% in visual analysis when considering the volume effect, necrosis, and metastasis. However, the specificity was only 58%-67%. Most lymph node and bone metastases could also be detected.(99m)Tc-3PRGD2 imaging at 1 h is sensitive for the detection of lung cancer, meriting further investigation of (99m)Tc-3PRGD2 as a novel clinical tracer for integrin receptor imaging.

The morphological evolution of ?' precipitates in a nickel-based superalloy K5 was studied by zone melting directional solidification under vacuum conditions. The results show that at the lower cooling rate of 12.42?K?s?1, ?' precipitates remand big cuboids. ?' particles become smaller at the cooling rate ranges from 12.42 to 38.80?K?s?1. For a rather fast cooling rate of 50.16?K?s?1, ?' particles retain a spherical shape. The experiments show that big cuboids will become unstable and split into several small ones at the lower cooling rate of 1.1?K?s?1. The mechanism of the evolution of the ?' morphologies is also analyzed by introducing a new parameter-shape factor which classifies the total energy into several energy levels. Based on this, the effect of the cooling rate on the ?' morphology is discussed.