Application of the IRAP Method Combined with GIS to Improve Road Safety on New Highway Projects in Algeria

This article aims to proactively predict high-risk accident areas in a new highway project in terms of its technical and geometric characteristics. The purpose of this study is to provide road project managers with better road safety assessment tools for the vehicle occupant category. The methodology used combines the International Road Assessment Program (IRAP) methodology and the Geographic Information System (GIS). The IRAP program enables the calculation and classification of risks for each 100-meter segment besides their categorization using a star rating; whereas, the GIS is used to map the risks and identify high-risk accident segments. This method was applied to a new highway project of 110 hectometres located in GHAZAOUET in Algeria. The results of the study revealed that this combined method is innovative in more than one way as it is an effective decision-making aid tool for road safety experts. It, therefore, makes it possible to target accident-prone sections in a faster way before carrying out on site road safety inspections. Technically speaking, this study shows that the existence of closely curved radii mixed at traffic speeds exceeding 80 km/h and the presence of road exits are the main factors affecting the safety of vehicle occupants. Speed control; thus, remains one among the cheapest measures to improve safety

Postbuckling Analysis of Functionally Graded Beams Using Nonlinear Model

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

Renforcement des poutres FGM par des plaques FRP (Cas d’imperfection de la poutre)

This work presents a method for determining the elastic shear and peel stresses in an adhesive joint between a strengthening plate and functionally graded beam (FGB). The beam is assumed to be isotropic with a constant Poisson’s ratio and exponentially-varying elastic modulus through the beam thickness. The effect of physical imperfection was introduced through a coefficient α which tends to reduce the value of Young modulus of beam FG. An analytical solution is proposed on the basic beam theory; several numerical examples are presented and discussed emphasizing the effect of different parameter governing the evolution of the interface stress.  Keywords: Adhesive stress – FGB Beam – Strengthenin

Using Qualitative Study and GIS to Explore Road Accident Black Areas in Algeria

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

Oxidative stress and histopathological changes induced by methylthiophanate, a systemic fungicide, in blood, liver and kidney of adult rats

Background: Methyl-thiophanate (MT), a fungicide largely used in agriculture throughout the world including Tunisia, protects many vegetables, fruits and field crops against a wide spectrum of fungal diseases. Oxidative stress has been proposed as a possible mechanism involved in MT toxicity on non-target organism.Methods: In the present study, the effect of MT injected intraperitoneally to adult rats at 300 or 500 mg/kg of body weight was studied on blood, liver and kidney.Results: Our results showed 3 days after MT injection, a significant decrease in hemoglobin and hematocrit values. A disruption in total white blood cells and platelets also occurred. Accordingly, an increased in malondialdehyde, H2O2 and advanced oxidation protein levels in liver and kidney were noted with the two doses. A significant change in plasma biomarkers and organ enzymatic and non-enzymatic activities were observed after MT treatment. The modifications in biochemical parameters were substantiated by histopathological data.Conclusion: These data confirmed the pro-oxidant effects of this fungicide. Accordingly, care must be taken to avoid mammalian and human exposure to MT.Keywords: Methyl-thiophanate, white blood cells, red blood cells, liver, kidne

Variable domain N-linked glycosylation and negative surface charge are key features of monoclonal ACPA: implications for B-cell selection

Autoreactive B cells have a central role in the pathogenesis of rheumatoid arthritis (RA), and recent findings have proposed that anti-citrullinated protein autoantibodies (ACPA) may be directly pathogenic. Herein, we demonstrate the frequency of variable-region glycosylation in single-cell cloned mAbs. A total of 14 ACPA mAbs were evaluated for predicted N-linked glycosylation motifs in silico and compared to 452 highly-mutated mAbs from RA patients and controls. Variable region N-linked motifs (N-X-S/T) were strikingly prevalent within ACPA (100%) compared to somatically hypermutated (SHM) RA bone marrow plasma cells (21%), and synovial plasma cells from seropositive (39%) and seronegative RA (7%). When normalized for SHM, ACPA still had significantly higher frequency of N-linked motifs compared to all studied mAbs including highly-mutated HIV broadly-neutralizing and malaria-associated mAbs. The Fab glycans of ACPA-mAbs were highly sialylated, contributed to altered charge, but did not influence antigen binding. The analysis revealed evidence of unusual B-cell selection pressure and SHM-mediated decreased in surface charge and isoelectric point in ACPA. It is still unknown how these distinct features of anti-citrulline immunity may have an impact on pathogenesis. However, it is evident that they offer selective advantages for ACPA+ B cells, possibly also through non-antigen driven mechanisms

Oxidative stress and histopathological changes induced by methylthiophanate, a systemic fungicide, in blood, liver and kidney of adult rats.

Background: Methyl-thiophanate (MT), a fungicide largely used in agriculture throughout the world including Tunisia, protects many vegetables, fruits and field crops against a wide spectrum of fungal diseases. Oxidative stress has been proposed as a possible mechanism involved in MT toxicity on non-target organism. Methods: In the present study, the effect of MT injected intraperitoneally to adult rats at 300 or 500 mg/kg of body weight was studied on blood, liver and kidney. Results: Our results showed 3 days after MT injection, a significant decrease in hemoglobin and hematocrit values. A disruption in total white blood cells and platelets also occurred. Accordingly, an increased in malondialdehyde, H2O2 and advanced oxidation protein levels in liver and kidney were noted with the two doses. A significant change in plasma biomarkers and organ enzymatic and non-enzymatic activities were observed after MT treatment. The modifications in biochemical parameters were substantiated by histopathological data. Conclusion: These data confirmed the pro-oxidant effects of this fungicide. Accordingly, care must be taken to avoid mammalian and human exposure to MT

Autoreactivity to malondialdehyde-modifications in rheumatoid arthritis is linked to disease activity and synovial pathogenesis

Oxidation-associated malondialdehyde (MDA) modification of proteins can generate immunogenic neo-epitopes that are recognized by autoantibodies. In health, IgM antibodies to MDA-adducts are part of the natural antibody pool, while elevated levels of IgG anti-MDA are associated with inflammatory conditions. Yet, in human autoimmune disease IgG anti-MDA responses have not been well characterized and their potential contribution to disease pathogenesis is not known. Here, we investigate MDA-modifications and anti-MDA-modified protein autoreactivity in rheumatoid arthritis (RA). While RA is primarily associated with autoreactivity to citrullinated antigens, we also observed increases in serum IgG anti-MDA in RA patients compared to controls. IgG anti-MDA levels significantly correlated with disease activity by DAS28-ESR and serum TNF-alpha, IL-6, and CRP. Mass spectrometry analysis of RA synovial tissue identified MDA-modified proteins and revealed shared peptides between MDA-modified and citrullinated actin and vimentin. Furthermore, anti-MDA autoreactivity among synovial B cells was discovered when investigating recombinant monoclonal antibodies (mAbs) cloned from single B cells. Several clones were highly specific for MDA-modification with no cross-reactivity to other antigen modifications. The mAbs recognized MDA-adducts in a variety of proteins. Interestingly, the most reactive clone, originated from an IgG1-bearing memory B cell, was encoded by germline variable genes, and showed similarity to previously reported natural IgM. Other anti-MDA clones display somatic hypermutations and lower reactivity. These anti-MDA antibodies had significant in vitro functional properties and induced enhanced osteoclastogenesis, while the natural antibody related high-reactivity clone did not. We postulate that these may represent distinctly different facets of anti-MDA autoreactive responses

Monoclonal IgG antibodies generated from joint-derived B cells of RA patients have a strong bias toward citrullinated autoantigen recognition

Antibodies targeting citrullinated proteins (ACPAs [anticitrullinated protein antibodies]) are commonly found in patients with rheumatoid arthritis (RA), strongly associate with distinct HLA-DR alleles, and predict a more aggressive disease course as compared with seronegative patients. Still, many features of these antibodies, including their site of production and the extent of MHC class II–driven T cell help, remain unclarified. To address these questions, we have used a single B cell–based cloning technology to isolate and express immunoglobulin (Ig) genes from joint-derived B cells of active RA patients. We found ∼25% of synovial IgG-expressing B cells to be specific for citrullinated autoantigens in the investigated ACPA+ RA patients, whereas such antibodies were not found in ACPA− patients. The citrulline-reactive monoclonal antibodies did not react with the unmodified arginine peptides, yet several reacted with more than one citrullinated antigen. A role for active antigen selection of the citrulline-reactive synovial B cells was supported by the strong bias toward amino acid replacement mutations in ACPA+ antibodies and by their loss of reactivity to citrullinated autoantigens when somatic mutations were reverted to the corresponding germline sequences