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Introduction:la dermatoscopie est une technique d'examen non invasive, permettant de donner un nouveau regard de la morphologie clinique des lésions pigmentées et des tumeurs cutanées. Nous montrons à travers notre série les caractéristiques morphologiques dermotoscopiques du carcinome basocellulaire (CBC) chez notre population. Méthodes:notre étude est une étude prospective unicentrique étalée sur une période de 2 ans. Nous avons utilisé le dermoscope chez tous les patients ayant un CBC. L'analyse statistique était réalisée à 'aide du logiciel SPSS version 17. Résultats:on avait recensé 100 CBC, L'âge moyen des patients était de 51,87 ans, avec un sex ratio F/H = 0,6. Le visage était la localisation la plus fréquente et la plupart des patients étaient de phototype III et IV. On a distingué des critères dermatoscopiques classiques et non classiques. On a montré qu'il existe une relation significative entre le phototype et le degré de la pigmentation des CBC. Conclusion:dans ce présent travail, le dermoscope était bénéfique d'une part pour détecter les CBC de petite taille, d'autre part pour faciliter le diagnostic des CBC pigmentés.

Background: The burden of stillbirth is so huge in sub-Saharan Africa, especially in Nigeria where many mothers and mothers-to-be are denied the joy of motherhood. Despite the frequent occurrence of this obstetric problem in our environment, little priority is placed on it. Objectives: The study aims to bring to the fore, the burden, trend, and characteristics of stillbirth delivery in Lagos, Nigeria. Subjects and Methods: This was a 5-year descriptive retrospective study of the case records of women who had stillbirth delivery at Lagos University Teaching Hospital from January 2009 to December 2013. Relevant information was obtained using a study pro forma, and data analysis was carried out using SPSS version 20.0. Results: The prevalence of stillbirth was 6.2%, and the rate was 61.8/1000 total births. Women who did not book for antenatal care accounted for 76.2% of the cases, and the antenatal and intrapartum stillbirths accounted for 64.6% and 35.4%, respectively. The mean gestational age was 35.5 ± 1.2 weeks, while the mean birth weight was 2.9 ± 1.0 kg. Majority of the stillbirths were male fetuses (54.5%). Previous history of stillbirth (36.0%), hypertensive disorders in pregnancy (33.0%), placental abruption (28.8%), intrauterine growth restriction (13.0%), and ruptured uterus (11.3%) were the common clinical risk factors identified. Conclusion: The burden of stillbirth is high in our environment, and majority is due to preventable or manageable obstetric conditions. There is a need to encourage early referral of complicated pregnancies and labor to specialized centers that can cater for them, so as to avoid unnecessary and preventable deaths.

Background: Epistaxis, though a mere nuisance can have life-threatening consequences. This first study from Jos on epistaxis aims to determine its sociodemographic characteristics, causes, the treatment modalities and the predictors of patient outcome. Study Design: A retrospective chart review. Methods: Health records of patients that met the inclusion criteria for epistaxis at the Jos University Teaching Hospital, Jos, Nigeria, between February 2011 and December 2015 were retrieved manually using standardized codes in the International Classification of Diseases 10th revision and studied for age, gender, associated comorbidities, treatment modalities offered, and outcome of treatment. Results: We managed 154 patients. Records of 92 patients were retrievable aged between 1 and 85 years (Mean = 37.7; standard deviation ± 16.2) with male to female ratio of 2.3:1. Patients in the third decade were the largest group. The most common cause was idiopathic. Anterior nasal bleeding occurred in 51.1%, posterior nasal bleeding in 34.8%. Conservative management was effective in 84.8%. Etiological factors other than chronic liver disease and otolaryngological malignancies showed statistically significant association with good patient outcomes (P = 0.013, P = 0.044, and P = 0.026, respectively). A mortality rate of 5.4% was recorded. Conclusion: Epistaxis of idiopathic origin occurring mostly in young males is the most common with most resolving on conservative management. Early hospital presentation, normal blood pressure at presentation and all management modalities were positive predictors of outcome in our patients.

In the field of numerical crash simulations in road safety research, there is a need to accurately define the initial conditions of a frontal impact for the car occupant. In particular, human models used to simulate such impacts barely take into account muscular contracting effects. This study aims to quantify drivers'behaviour in terms of posture and muscular activity just before a frontal impact. Experiments on volunteers were performed in order to define these conditions, both on a driving simulator and on a real moving car. Brake pedal loads, lower limbs kinematics and muscle activation were recorded. Coupling instantaneous data from both experimental protocols (simulator versus Real car), a standard emergency braking configuration could be defined as (1) joint flexion angles of 96◦, 56◦ and 13◦ for the right hip, knee and ankle respectively; (2) a maximum brake pedal load of 780 N; (3) a muscular activation of 55% for the anterior thigh, 26% for the posterior thigh, 18% for the anterior leg and 43% for the posterior leg. The first application of this research is the implementation of muscle tone in human models designed to evaluate new safety systems. Driving behaviour, Driving simulator, Electromyography, Motor vehicle crashes, Emergency braking

Setting a method to evaluate the mechanical properties of an aged asphalt mix using a rapid chemical measurement from small samples, would be of high interest at different steps of a road structure life cycle: at the design step, to optimise the estimates of the service lifetime usually based on the properties of unaged materials; during the service life, to update the residual lifetime expectation of an existing structure according to the actual properties of the in situ aged materials; and at the end of the service life or for maintenance management, to evaluate the recyclability of the materials of the structure. This study was carried out aiming at comparing results from Fourier Transform InfraRed and Dynamic Shear Rheometer tests. Experimental data came from an international round robin test, organised by the RILEM TC ATB, designed to set an ageing protocol on loose bituminous mixtures. The evolutions of the carbonyl index (ICO) calculated from the FTIR spectra are compared to the evolutions of the parameters of a modified Huet Rheological Model (1S2P1D) fitted on the experimental linear viscoelastic data measured on the recovered binder. A significant relationship is observed suggesting that chemical and rheological properties could be correlated. Based on this observation, a method is proposed for predicting the G* values of a binder aged at a given ΔICO level. Subsequently, this method could be used to predict the complex modulus E* of a given mix from the shear modulus G* of the binder using existing binder/mix transfer models.

INTRODUCTION: La tuberculose (TB) reste de nos jours un problème majeur de santé publique dans les pays en voie de développement. Elle devient de plus en plus importante à cause de l'infection au VIH. Cette étude avait pour but de caractériser les patients admis dans le plus grand Centre de Diagnostic et de Traitement de la Tuberculose (CDT) de l'Ouest Cameroun entre 2000 et 2009. METHODES: Les patients de 15 ans et plus admis au CDT de Baleng durant la période allant du 1er janvier 2000 au 31 décembre 2009 ont été inclus. Les données ont étés collectées grâce à une grille pré conçue. Le calcul des fréquences, moyennes et les comparaisons de groupes ont été faites pour ressortir les caractéristiques des participants. RESULTATS: 2556 patients ont été inclus dans l'étude. 64,8% étaient de sexe masculin et l'âge médian étaient de 33ans. 2141 (83,7%) de patients présentaient une TPM+, 319 (12,5%) une TPM- et 96 (3,8%) une TEP. 64,7% des patients résidaient hors du district de santé di'mplantation du CDT. 79,16% de patients tuberculeux ont fait le test de dépistage du VIH et la séroprévalence chez ceux testés était de 26,06%. Les différentes évolutions en fin de période de suivi de chaque patient ont été les suivantes: évolution favorable (guéri et traitement terminé) 1954(76,6%) ; perdus de vue 231(9,0%) ; décès 230(9,0%) ; transféré 92(3,6%) ; échec 49(1,9%). CONCLUSION: Une proportion considérable de patients résident loin du CDT ce qui augmenterait le perdus de vue et les transferts pendant le traitement. En plus vulgariser les autres CDT de la région, il est nécessaire de renforcer le système de transfert pour éviter les perdus de vue entre deux CDT.

Finite element models (FEM) dedicated to vertebral fracture simulations rarely take into account the rate dependency of the bone material properties due to limited available data. This study aims to calibrate the mechanical properties of a vertebral body FEM using an inverse method based on experiments performed at slow and fast dynamic loading conditions. A detailed FEM of a human lumbar vertebral body (23,394 elements) was developed and tested under compression at 2,500 and 10 mm s⁻¹. A central composite design was used to adjust the mechanical properties (Young modulus, yield stress, and yield strain) while optimizing four criteria (ultimate strain and stress of cortical and trabecular bone) until the failure load and energy at failure reached experimental results from the literature. At 2,500 mm s⁻¹, results from the calibrated simulation were in good agreement with the average experimental data (1.5% difference for the failure load and 0.1% for the energy). At 10 mm s⁻¹, they were in good agreement with the average experimental failure load (0.6% difference), and within one standard deviation of the reported range of energy to failure. The proposed method provides a relevant mean to identify the mechanical properties of the vertebral body in dynamic loadings.

Computational models are developed in injury biomechanics to assess lesions in biological tissues based on mechanical measurements. The linear mechanics of fracture theory (LMFT) is a common approach to establish injuries based on thresholds (such as force or strain thresholds) which are straightforward to implement and computationally efficient. However, LMFT does not apply to non-linear heterogeneous materials and does not have the ability to predict failure onset. This paper proposes the cohesive zone model theory (CZMT) as an alternative. CZMT focuses on the development of behaviour laws for crack initiation and propagation at an interface that apply within a fibrous material or at the interface between materials. With the view of evaluating CZMT for biological tissues, the model developed by Raous et al. [1999. A consistent model coupling adhesion, friction and unilateral contact. Comput. Methods Appl. Mech. Eng., 177, 383-399] was applied to the ligament-to-bone interface in the human knee joint. This model accounts for adhesion, friction and damage at the interface and provides a smooth transition from total adhesion to complete failure through the intensity of adhesion variable. A 2D finite element model was developed to mimic previous experiments, and the model parameters were determined using a dichotomy method. The model showed good results by its ability to predict damage. The extension to a 3D geometry, with an inverse problem approach, is, however, required to better estimate the model parameters values. Although it is computationally costly, CZMT supplements the improvements achieved in microimaging techniques to support the development of micro/macro approaches in biomechanical modelling. Adhesion Cohesive zone model Failure Micromechanics Ligament-to-bone attachment Damage

The aim of this study was to evaluate the mechanical properties of bone components of the vertebral body. An inverse finite element strategy was used to estimate the properties of cortical and trabecular bone. These mechanical properties have been evaluated at two velocities in order to investigate the influence of the displacement rate

International audience; In the last decade, many finite element (FE) models of the spine were used as surrogate experiments to provide relevant knowledge on the biomechanics of spinal trauma [1-2]. One of the major concerns in the development of such model is the modeling and validation of the spinal components’ mechanical behavior in dynamic loading conditions. For instance, very few FE models have considered the strain rate dependency shown by the intervertebral disk (IVD) when submitted to high strain rates [3], thus limiting their ability to represent traumatic conditions. Such limitations arise from the lack of appropriate material properties available in the literature. Thus, the purpose of the current study was to determine suitable material properties of the IVD for its FE modeling under dynamic compressive loads. Lumbar spine; Material properties; Finite element analysis; Reliability study, High strain rate.

BACKGROUND: The trunk of a car occupant can be injured by a frontal or lateral impact. Lesions can be either intrusion injuries or due to the effects of deceleration alone. The aim of this study conducted with human cadavers was to explore the effects of deceleration on the liver during frontal or lateral deceleration. METHODS: Trunks previously instrumented with accelerometers in three sites, the left and right lobes of the liver and the retrohepatic inferior vena cava, were subjected to substantial deceleration in three orientations: frontal, left, and right lateral. The anatomic consequences and deceleration data were measured. A deceleration ratio was defined as a peak deceleration measured in the liver divided by peak deceleration imposed on the trunk. RESULTS: Peak deceleration imposed on the trunks was up to 60 g, which caused peak deceleration up to 26 g in the liver. No anatomic injury was observed. For each orientation, deceleration ratios were not significantly different among the three sites (p = 0.64) or between left and right lateral decelerations (p = 0.12). Deceleration ratios were significantly different (p = 0.001) between frontal (3 sites combined) and lateral (3 sites of left and right lateral orientations combined) decelerations: 39.4% (+/-6) versus 48.4% (+/-11). CONCLUSIONS: In conclusion, at tested decelerations, under the hepatic injury threshold, cadaveric liver seemed to be subjected to higher deceleration when the trunk was decelerated in lateral than in frontal direction, without terminal impact. Language: en