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Normal computation and front intersection detection for boundary layer mesh generation are the most time-consuming parts in implementing a robust hybrid meshing tool for viscous flow simulations. This paper presents a generalized boundary layer meshing method with a fast collision detecting algorithm. The main works are as followings. Firstly, a novel continuous medial-surface representation method is proposed by splitting a constrained Delaunay triangulation (CDT) of boundary points in a linear complexity. Secondly, we enhance a Jump-and-Walk method for mesh intersection detecting by improving its robustness with a medial-surface wall introduced between marching fronts, which only relies on CDT and is simple to implement as no extra data structures are required. Finally, a concise domain partitioning and advancing method is used to significantly reduce the times of the normal computation and intersection detection operations at an extremely low price by sharing the CDT. The capability of the proposed algorithm is demonstrated by generating quality hybrid mesh for several models with complex configurations. The results show that it may be able considerably reduce the effort to implement a robust hybrid meshing program with a speed of about 4 times faster than a popular commercial software Pointwise for researchers. [ABSTRACT FROM AUTHOR]

Introduction: X-linked hypophosphatemia (XLH) is a rare, lifelong, progressive disease characterised by renal phosphate wasting and abnormal bone mineralisation. Symptoms begin in early childhood, with the development of rickets and related skeletal deformities and reduced growth, progressing to long-term complications, including pseudofractures and fractures, as well as pain, stiffness and fatigue. The present study was designed to explore the patient experience of pain, stiffness and fatigue and the psychosocial impact of XLH in detail.Methods: A cross-sectional qualitative study was conducted in the United Kingdom (18), Finland (6), France (4), Germany (1) and Luxembourg (1) with XLH patients aged 26 and over. Interview discussion guides were developed in consultation with clinical experts and patient associations. Data were analysed thematically.Results: Participants (N = 30) described pain, stiffness and fatigue as frequently experienced symptoms with a significant impact on physical functioning and activities of daily living (ADLs). Some also described the symptoms as impacting their mood/mental health, relationships, social life and leisure activities. Participants described how common symptoms could interact or aggravate other symptoms. Symptoms had often worsened over time, and for many, were associated with concern about the future. Most participants were worried or felt guilty about having children with XLH. The findings confirmed and extended the existing model of the burden of XLH.Conclusion: The present study is the first to provide an in-depth analysis of pain, stiffness and fatigue, their impact and the interrelatedness of these symptoms among adults with XLH. The study also described the psychosocial impact of XLH as a hereditary, lifelong progressive disease. [ABSTRACT FROM AUTHOR]

Objectives:Most types of population-based cancer screening require repeat participation to be effective. This study investigated predictors of repeat participation in the NHS Bowel Cancer Screening Programme (BCSP).Methods:The BCSP in England offers biennial colorectal cancer screening using a guaiac fecal occult blood test (gFOBt) from age 60-74 years. This analysis included 62 081 individuals aged 60-64 years at the time of the first invitation (R1). The main outcome was repeat participation at their second (R2) or third (R3) invitation. Behavioural measures derived from screening records included late return of the gFOBt kit, compliance with follow-up investigations and previous screening participation. Other potential predictors of repeat participation included results of individual test kit analysis (normal, weak positive, strong positive, spoilt) and the definitive result of the gFOBt screening episode (normal or abnormal). Age, sex and socioeconomic deprivation were also recorded.Results:Overall repeat uptake was 86.6% in R2 and 88.6% in R3. Late return of the test kit was consistently associated with lower uptake (R2: 82.3% vs 88.6%, P<0.001; R3: 84.5% vs 90.5%, P<0.001). A definitive abnormal gFOBt result in the previous screening episode was a negative predictor of repeat uptake (R2: 61.4% vs 86.8%, P<0.001; R3: 65.7% vs 88.8%, P<0.001). Weak positive (R2: 76.9% vs 86.8%, P<0.001; R3: 81.7% vs 88.8%, P<0.05) and spoilt test kits (R2: 79.0% vs 86.6%, NS; R3: 84.2% vs 92.2%, P<0.05) were associated with lower repeat uptake, but were not consistently independent predictors in all invitation rounds or subgroups. Among those with a definitive abnormal gFOBt result, noncompliance with follow-up in a previous screening episode was also associated with lower repeat uptake (R2: 24.3% vs 67.1%, P<0.001; R3: 43.2% vs 69.9%, P<0.001).Conclusions:Behavioural markers and test results from previous screening episodes have been implicated in subsequent gFOBt uptake. [ABSTRACT FROM AUTHOR]

CTEN/TNS4 is an oncogene in colorectal cancer (CRC), which can induce cell motility although its mechanistic basis of activity and the clinical implications of Cten expression are unknown. As Cten is in complex with integrins at focal adhesions, we hypothesised that it may interact with integrin-linked kinase (ILK). Through forced expression and knockdown of Cten in HCT116 and SW620 (respectively, showing low and high Cten expression), we showed that Cten could regulate ILK. However, inhibition of ILK after forced expression of Cten abrogated the motility-inducing effects of Cten, thereby demonstrating that the Cten-ILK interaction was functionally relevant. Combined knockdown of Cten and ILK had no additive effects on cell motility compared with knockdown of each individually. In order to investigate the clinical implications of Cten expression, a series of 462 CRCs were evaluated by immunohistochemistry. High expression of Cten was associated with advanced Dukes' stage (P<0.001), poor prognosis (P<0.001) and distant metastasis (P=0.008). The role of Cten in metastasis was tested by (a) intrasplenic injection of CRC cells stably transfected with a Cten expression vector into nude mice and (b) testing a series of primary human CRCs and their metastases by immunohistochemistry. Compared with controls, mice injected with cells expressing Cten developed larger tumours in the spleen (P<0.05) and liver (P<0.05). In the human cases, compared with primary tumours, the metastatic deposits had a significantly higher frequency of nuclear localisation of Cten (P=0.002). We conclude that Cten expression is of prognostic significance in CRC, and we delineate a Cten-ILK pathway controlling cell motility and possibly promoting metastasis. [ABSTRACT FROM AUTHOR]

This paper studies the three-dimensional (3-D) free vibration of uniform prisms with isosceles triangular cross-section, based on the exact, linear and small strain elasticity theory. The actual triangular prismatic domain is first mapped onto a basic cubic domain. Then the Ritz method is applied to derive the eigenfrequency equation from the energy functional of the prism. A set of triplicate Chebyshev polynomial series, multiplied by a boundary function chosen to, a priori, satisfy the geometric boundary conditions of the prism is developed as the admissible functions of each displacement component. The convergence and comparison study demonstrates the high accuracy and numerical robustness of the present method. The effect of length-thickness ratio and apex angle on eigenfrequencies of the prisms is studied in detail and the results are compared with those obtained from the classical one-dimensional theory and the 3-D finite element method. Sets of valuable data known for the first time are reported, which can serve as benchmark values in applying various approximate beam and rod theories. [ABSTRACT FROM AUTHOR]

Deleted in liver cancer 1 (DLC1) is a RhoGTPase activation protein-containing tumor suppressor that associates with various types of cancer. Although DLC2 shares a similar domain structure with that of DLC1, the function of DLC2 is not well characterized. Here, we describe the expression and ablation of DLC2 in mice using a reporter-knockout approach. DLC2 is expressed in several tissues and in endothelial cells (ECs) of blood vessels. Although ECs and blood vessels show no histological abnormalities and mice appear overall healthy, DLC2-mutant mice display enhanced angiogenic responses induced by matrigel and by tumor cells. Silencing of DLC2 in human ECs has reduced cell attachment, increased migration, and tube formation. These changes are rescued by silencing of RhoA, suggesting that the process is RhoA pathway dependent. These results indicate that DLC2 is not required for mouse development and normal vessel formation, but may protect mouse from unwanted angiogenesis induced by, for example, tumor cells. [ABSTRACT FROM AUTHOR]

An integral formulation for 2D cracked infinite anisotropic magneto–electro–elastic media is presented. Based on the method proposed by Garcia-Sanchez et al. (Comput Struct 83: 804–820, 2005), the hypersingular kernels are analytically transformed into weakly singular and regular integrals with known analytical solution. Special quadratic discontinuous crack tip elements are employed to model the singular characteristics of the stresses, electric displacements and magnetic inductions. The extended stress intensity factors at the crack tips are calculated using the extended discontinuous displacements at crack tip elements based on one point extended displacement formulation. Some results for curved cracks in magneto–electro–elastic media are also presented. [ABSTRACT FROM AUTHOR]

Background: Endoscopic removal of large sessile polyps is sometimes technically difficult and is associated with an increased risk of complications. Moreover, the incidence of invasive carcinoma within these polyps is not negligible. Laparoscopic colorectal resection has been recommended in the treatment of these large polyps. This study aimed to evaluate the outcomes of laparoscopic colorectal resection for polyps that were not suitable for colonoscopic removal.Methods: Forty-five patients (28 men and 17 women) who underwent laparoscopic colorectal resection with the preoperative diagnosis of colorectal polyps were analyzed. The reasons for surgical resection were large sessile polyps (n = 34), difficult position (n = 2), recurrence after transanal endoscopic microsurgery (n = 1), and the presence of intramucosal malignancy on histology after colonoscopic polypectomy (n = 8).Results: The mean age of the patients was 66.7 years (range, 33-89). Previous abdominal operation had been performed in 12 patients (26.7%). Two patients underwent subtotal colectomy because of multiple polyps (14 and 19, respectively). Synchronous resection of other organs was performed in two patients (a right salpingo-oophorectomy and a right adrenalectomy). Intraoperative complications occurred in two patients, and two patients (4.5%) required conversion because of perforation of the colon during dissection and dense adhesions, respectively. There was no postoperative mortality. Complications occurred in seven patients (15.6%), and they included postoperative ileus (n = 4), anastomotic leakage (n = 1), urinary retention (n = 1), and urinary tract infection (n = 1). Reoperation was required in one patient for anastomotic leakage. The median hospital stay was 6 days. The histopathology of colorectal polyps showed tubular (n = 12), tubulovillous (n = 13), and villous adenoma (n = 12); mixed adenomatous/hyperolastic polyps (n = 2); inflammatory polyp (n = 1); and colonic lipoma (n = 1). Four patients, who had previous polypectoray with intramucosal malignancy, had no residual pathology. The median size was 3.0 cm. Invasive carcinoma was found in 16 patients (35.6%). The median number of lymph node sampling was six, and two patients had lymph node metastases.Conclusions: Colonic polyps that were not amendable for colonoscopic removal were associated with a high incidence of malignant invasion. Laparoscopic colectomy offers safe and effective management of these polyps with the benefits of early postoperative recovery. [ABSTRACT FROM AUTHOR]

Abstract An integral equation approach is presented to investigate the interaction between cracks and rigid-line inclusions embedded in an infinite isotropic elastic matrix subject to remote loading. The relevant fundamental solutions in the integral formulation are presented. Special tip elements are used to simulate the &ratic;r variation of the discontinuous displacements over the crack surfaces, and the axial and shear forces along the rigid-line inclusions. The stress intensity factors at the crack tips and at the ends of the rigid-line inclusions are computed and compared with available solutions. [ABSTRACT FROM AUTHOR]

A general-purpose integral formulation is proposed for the analysis of the interaction between inclusions and tracks embedded in an elastic isotropic homogenous infinite medium subjected to a remote loading. This formulation is tailored for the inclusions of arbitrary shapes with the presence of cracks. The discretization is limited to the inclusions (with continuous quadratic triangular and quadrilateral elements) and the cracks (using discontinuous quadratic elements). For the calculation of the stress intensity factors at the crack tips, special crack tip elements are used to model the square root r variation of the displacements near the crack tips. Maximum circumferential stress criterion is adopted to determine the crack propagating direction. Numerical results of benchmark examples are compared with other available methods. [ABSTRACT FROM AUTHOR]

In this paper, an integral equation method to the inclusion-crack interaction problem in three-dimensional elastic medium is presented. The method is implemented following the idea that displacement integral equation is used at the source points situated in the inclusions, whereas stress integral equation is applied to source points along crack surfaces. The displacement and stress integral equations only contain unknowns in displacement (in inclusions) and displacement discontinuity (along cracks). The hypersingular integrals appearing in stress integral equation are analytically transferred to line integrals (for plane cracks) which are at most weakly singular. Finite elements are adopted to discretize the inclusions into isoparametric quadratic 10-node tetrahedral or 20-node hexahedral elements and the crack surfaces are decomposed into discontinuous quadratic quadrilateral elements. Special crack tip elements are used to simulate the variation of displacements near the crack front. The stress intensity factors along the crack front are calculated. Numerical results are compared with other available methods. [ABSTRACT FROM AUTHOR]

A simple and efficient refinement procedure for the three-dimensional tetrahedral element mesh based on successive bisection of edges is proposed. The quality of the elements generated can be guaranteed if the subdivision is performed in the sequence according to the length of the line segments to be divided. Such an order of priority can be determined by a simple sorting process on all the line segments for which refinement is needed. This list of ordered line segments has to be updated from time to time to take into account of the new line segments generated during the subdivision process. From the examples studied, the CPU time for mesh refinement bears a linear relationship with the number of elements generated, with a refinement rate of more than 50 000 elements per second on a IBM Power Station 3BT. Shape optimization procedures can be applied to the refined mesh to further improve the quality of the elements. The refinement scheme is useful as part of a general three-dimensional mesh generation package, or as the mesh refinement module in an adaptive finite element analysis. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor referring to a case of sphenoid sinus mucocoele presenting with optic neuropathy and abducens palsy.