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In this article, an exact analytical solution for mechanical buckling analysis of magnetoelectroelastic plate resting on pasternak foundation is investigated based on the third-order shear deformation plate theory. The in-plane electric and magnetic fields can be ignored for plates. According to Maxwell equation and magnetoelectric boundary condition, the variation of electric and magnetic potentials along the thickness direction of the plate is determined. The von Karman model is exploited to capture the effect of nonlinearity. Navier's approach has been used to solve the governing equations for all edges simply supported boundary conditions. Numerical results reveal the effects of (i) lateral load, (ii) electric load, (iii) magnetic load and (iv) higher order shear deformation theory on the critical buckling load have been investigated. These results must be the analysis of intelligent structures constructed from magnetoelectroelastic materials. [ABSTRACT FROM AUTHOR]

In the present article, equilibrium and stability equations of rectangular functionally graded plates are determined using the new hyperbolic shear deformation theory. Unlike any other theory, the theory presented gives rise to only four governing equations. Number of unknown functions involved is only four, as against five in case of simple shear deformation theories of Mindlin and Reissner (first shear deformation theory). It is assumed that the material properties vary with the power product form of thickness coordinate variable z. The equilibrium and stability equations are employed to study the buckling behavior of functionally graded plates with all edges simply supported and subjected to in-plane loading conditions. The results obtained are compared with their counterparts in the literature. [ABSTRACT FROM AUTHOR]

This work aims to explore black areas identification through a qualitative methodology based mainly on a series of questionnaires and interviews and by a development of a geographical information system on the road accidents in studied area. The road user, particularly the driver, is generally considered as the first person in charge in the case of accident, while his opinion is rarely joined into the establishment of the solutions to the problems of the road insecurity. Considering needs for the treatment of black areas, problems of the lack of data on the accidents, the different advantages that suggests the concept of participation and the feasibility integrating the road users into the analysis of the road safety. The Qualitative study aims at supplying with the accessibility for the users of the road to indicate the places of male performances of safety according to their feeling and of them the experience. The approach by the GIS aims at first to establish road accidents on the studied site by associating data of different nature and then to make a spatial analysis via ArcGis tool. The study area is a section of national road Highway RN6 of 38 Kms (from the PK00 to the PK38) which across the wilaya of Mascara. it is considered a potentially dangerous stretch in terms of road insafety. The results of this study show that the road users are the daily witnesses on the degree of the danger which presents their usual territory: the road. They can, therefore, to be the complementary information source for the localization of zones at high risk on the road network traveled daily. [ABSTRACT FROM AUTHOR]

The major novelty of the paper in the study, post-buckling of simply supported FGM beams using various theory, classical beam theory (CBT), first-order shear deformation beam theory (FSDBT), parabolic shear deformation beam theory (PSDBT) and exponential shear deformation beam theory (ESDBT). Governing equations of FGM beam for post-buckling problem were found by applying Hamilton principle and Navier type solution method was used to solve post-buckling problem. It is assumed that elasticity modulus is changing in the thickness direction and all other material properties are taken to be constant. Variation of elasticity modulus in the thickness direction, are described by a simple power law distribution in terms of the volume fractions of constituents. The shear effect is shown to have a significant contribution to both the buckling and post-buckling behaviors. Results of this analysis show that classical and first-order theories underestimate the amplitude of buckling while all higher order theories, considered in this study, yield very close results for the static post-buckling response. [ABSTRACT FROM AUTHOR]

Objectives: Rheumatoid arthritis (RA)-specific anti-citrullinated protein/peptide antibodies (ACPAs) appear before disease onset and are associated with bone destruction. We aimed to dissect the role of ACPAs in osteoclast (OC) activation and to identify key cellular mediators in this process.Methods: Polyclonal ACPA were isolated from the synovial fluid (SF) and peripheral blood of patients with RA. Monoclonal ACPAs were isolated from single SF B-cells of patients with RA. OCs were developed from blood cell precursors with or without ACPAs. We analysed expression of citrullinated targets and peptidylarginine deiminases (PAD) enzymes by immunohistochemistry and cell supernatants by cytometric bead array. The effect of an anti-interleukin (IL)-8 neutralising antibody and a pan-PAD inhibitor was tested in the OC cultures. Monoclonal ACPAs were injected into mice and bone structure was analysed by micro-CT before and after CXCR1/2 blocking with reparixin.Results: Protein citrullination by PADs is essential for OC differentiation. Polyclonal ACPAs enhance OC differentiation through a PAD-dependent IL-8-mediated autocrine loop that is completely abolished by IL-8 neutralisation. Some, but not all, human monoclonal ACPAs derived from single SF B-cells of patients with RA and exhibiting distinct epitope specificities promote OC differentiation in cell cultures. Transfer of the monoclonal ACPAs into mice induced bone loss that was completely reversed by the IL-8 antagonist reparixin.Conclusions: We provide novel insights into the key role of citrullination and PAD enzymes during OC differentiation and ACPA-induced OC activation. Our findings suggest that IL8-dependent OC activation may constitute an early event in the initiation of the joint specific inflammation in ACPA-positive RA. [ABSTRACT FROM AUTHOR]

Breast carcinoma is a major cause of death among women, and the potential implication of viruses in its pathogenesis remains worth a hypothesis. The potential role of Epstein-Barr virus (EBV) in its pathogenesis is still a subject of continued discussion and investigation. The aim of this study was to evaluate the prevalence of EBV in sporadic breast cancers in Tunisia, and to determine the clinicopathological characteristics of virus-positive cases. Viral presence has been evaluated by polymerase chain reaction (PCR), in situ hybridization, and immunohistochemistry investigated on tumor tissues and their corresponding normal breast tissues collected from 123 Tunisian women with sporadic breast carcinomas. Viral status in tumors was then correlated with various clinicopathological parameters. Using specific PCR assays, EBV DNA was found in 33 (27%) out of 123 breast carcinoma cases. EBV-encoded small RNAs (EBERs) in situ hybridization was negative in the neoplastic cells, but stomal lymphocytes were positive in 4 cases. Immunohistochemistry for latent membrane protein 1 (LMP1) was negative in all cases. None of the normal breast tissues showed positive results for EBV using PCR, in situ hybridization, and immunohistochemistry. A correlation was found between EBV DNA presence and the negativity of estrogen receptor (P=0.008). However, no significant correlation was found for the other parameters investigated, including patient age, Scarff-Bloom-Richardson (SBR) histological grade, tumor size, and histological node involvement. With regard to survival data, overall and disease-free survivals were shorter in EBV-positive breast carcinoma cases than in EBV-negative ones, but this difference did not reach statistical significance. Our study indicates the presence of EBV DNA in a significant proportion of breast cancer in Tunisia. Further studies are required to elucidate the role of this virus in breast carcinogenesis., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

The association between human papillomavirus (HPV) infection and development of bladder cancer is variable. Furthermore, the prevalence of HPV DNA in bladder carcinoma subtypes varies from study to study. To clarify the impact of HPV infection on the development of bladder carcinoma, we performed a retrospective study on Tunisian patients to determine the status of HPV infection in urothelial carcinoma, squamous cell carcinoma, and adenocarcinoma. A total of 125 formalin-fixed, paraffin-embedded archival tissue specimens of bladder carcinoma were reviewed and classified according to the World Health Organization (WHO) classification of tumors (119 urothelial carcinomas, five squamous carcinomas, and one adenocarcinoma). Anogenital HPV DNA detection was performed using three different polymerase chain reaction (PCR) techniques: the first one used primers pU-2R/pU-1M specific to high-risk oncogenic HPV; the second one used primers PU-2R/PU-31B specific to low-risk oncogenic HPV; and the third one employed consensus primers (E1-547R/E1-350L). No evidence of HPV infection was detected by morphological examination and PCR in any case of bladder carcinoma. Our study shows that the anogenital HPVs investigated are not associated with the pathogenesis of bladder cancer in Tunisia; however, the question of whether other subtypes of HPV contribute to bladder carcinogenesis remains to be clarified., (Copyright © 2010 Elsevier GmbH. All rights reserved.)

The aim of this study was to evaluate the frequency of "high-risk" HPV types in condyloma acuminata in patients from Tunisian Center. Thirty two paraffin-embedded biopsies were analysed for the presence and type of HPV DNA by means of in situ hybridization (ISH) and polymerase chain reaction (PCR) techniques. ISH was done using a broad spectrum HPV biotinylated DNA probe for the detection of HPV DNA. HPV typing was carried out using specific probes for HPV types 6/11, 16/18 and 31/33. HPV DNA was amplified by PCR using the degenerate primers E1350L/E1547. HPV were typed by pU-1M/PU-2R primers for the oncogenic HPV types 16, 18, 31 and 33, and PU-31B/PU-2R for "low-risk" group (6 and 11). Using ISH, HPV was detected in 27 out 32 cases (84.4%). All were HPV 6/11 positive. Co-infection with oncogenic HPV was found in one case that reacted with 16/18 and 31/33 probes. Good quality DNA was obtained in 13 cases. HPV was detected by PCR in 11 of 13 specimens (80.6%) when E1350L/E1547 primers were used. HPV 6/11 were present in all cases. The results of this study provide specific confirmation of the predominance of HPV6/11 and low rate of co-infection in patient from Tunisian Center. Because of the difficulty of DNA extraction, risk of DNA degradation and contamination associated with PCR, the ISH remains more adapted to archival materiel especially in routine clinical practice.

Polymerase chain reaction (PCR)-based analysis, employed for detecting immunoglobulin heavy chain (IgH) gene rearrangements, has become a diagnostic tool widely used in the investigation of B-cell lymphomas, but the overall sensitivity of these methods does not exceed 80%, notably in germinal center (GC) and post-GC B-cell origin lymphomas. Many PCR strategies devised for detecting immunoglobulin light chain (IgL) gene rearrangements have been developed to enhance the clonality detection rates. However, the feasibility of these methods in routine clinical diagnosis using paraffin-embedded tissues has not yet been investigated sufficiently. We studied a large series of 108 cases of B-cell lymphomas, as well as 20 reactive lymphoid tissues using degenerate primers to amplify immunoglobulin kappa (Igkappa) and lambda (Iglambda) light chain genes. B-cell clonality was further investigated using semi-nested PCR for IgH gene rearrangements. B-cell clonality was detected in 74%, 56.5%, and 43.5% of cases using IgH, Igkappa, and Iglambda PCR, respectively. By combining these methods, the clonality detection rate increased to 93.5%. Only polyclonal patterns were noted in reactive lymphoid samples. We concluded that in addition to the established methods for IgH analysis, a PCR-based approach for IgL gene rearrangements analysis improves the clonality detection rate in over 90% of B-cell lymphoma cases using routine histological specimens with poor preservation of the genomic DNA.