Facteurs du ravinement dans la dorsale tunisienne et le cap bon

Au sein d’une stratégie nationale de mobilisation des eaux de surface, la Tunisie a réalisé près de 700 lacs et barrages collinaires depuis les années 90, principalement dans la Dorsale tunisienne et le Cap Bon. En contribuant à l’envasement de ces retenues, l’érosion hydrique diminue la capacité de mobilisation. Pour raisonner une stratégie de lutte anti-érosive dans les bassins versants qui soit plus efficace que ce qu’elle n’est actuellement, il est fondamental de mieux identifier et comprendre les principaux mécanismes responsables de l’envasement des retenues. En milieu méditerranéen, le rôle des très nombreux systèmes ravinaires a plusieurs fois été pointé du doigt pour expliquer l’envasement rapide de certaines retenues.Dans ce contexte, le présent travail se fixe comme objectif d’évaluer, à l’échelle de la Dorsale et du Cap Bon, les facteurs qui expliquent la présence et la dynamique morphologique actuelle du ravinement.Pour cela, une démarche en trois étapes a été retenue. Il s’agit d’abord de cartographier, sous SIG, l’évolution des caractéristiques (position, caractéristiques géométriques, processus actifs) du réseau hydrographique (oueds et ravins) sur une période de plus de 50 ans par interprétation de différents jeux de photographies aériennes actuelles et historiques. Une cartographie des facteurs, aussi bien bio-physiques (géologie/pédologie et pente) qu’anthropiques (occupation du sol et aménagements), susceptibles d’expliquer la présence et la morpho-dynamique des systèmes ravinaires est également réalisée. La seconde étape consiste à établir le rôle des facteurs biophysiques et anthropiques sur la présence de ravins en analysant les corrélations spatiales entre facteurs et présence de ravins pour l’ensemble des dates analysées. La dernière étape consiste à analyser le rôle associé de ces mêmes facteurs et du climat sur la dynamique du ravinement en recherchant cette fois ci des corrélations spatiales entre facteur et évolution des longueurs de ravins pour chaque période séparant deux cartographies.Cette démarche, mise en oeuvre sur plusieurs bassins versants représentatifs de la diversité des contextes de la Dorsale Tunisienne et du Cap Bon, permet de quantifier les facteurs prépondérants de la distribution et de la dynamique actuelle des ravins sur chaque bassin et à l’échelle de la Dorsale Tunisienne et du Cap Bon. La lithologie et la pente sont les deux facteurs les plus impliqués dans l’explication de la présence des ravins. En fait, la lithologie formée de roche dure montre beaucoup moins de densité de ravins que les autres lithologies (intercalation roche tendre/roche dure, et roche tendre). Par contre, plus la pente est élevée plus la densité des ravins est forte. La dynamique dans le temps du ravinement dans la Dorsale tunisienne et le Cap Bon est fortement dépendante du facteur climatique et des interventions humaines (aménagements de conservation des eaux et des sols et défrichement de la forêt)

Paratesticular Liposarcoma: What is the Best Therapeutic Strategy?

Introduction: Liposarcomas are neoplasms of mesodermal origin derived from adipose tissue and correspond to 10–14% of all soft tissue sarcomas. Paratesticular liposarcoma is very rare.Case report: We report a 60-year old man who presented with a left testicular tumor 20 cm in diameter. Initial incisional biopsy was reported as fibromatosis. Chest and abdominal CT scan did not show distant metastases. Through an inguinal incision orchidectomy with homolateral inguinal node dissection was performed. Histopathological examination showed a paratesticular myxoid liposarcoma. Adjuvant radiotherapy without chemotherapy was administered. The patient remains well at 11 months followup, with no evidence of recurrence.Conclusion: Complete surgical extirpation reduces the risk of local recurrence. Neoadjuvant chemotherapy or radiotherapy may reduce the tumor size, thus facilitating complete excision

Appendagite épiploïque primitive: à propos de cinq cas

La torsion de frange épiploïque (ou appendagite) est une pathologie rare qui survient principalement chez les adultes entre 20 et 50 ans.L'incidence de cette pathologie n'est pas réellement connue et elle varie de 2 à 7% chez les patients hospitalisés pour suspicion d'appendicite oude sigmoïdite. Nous rapportons cinq cas d'appendagites dont nous précisons les particularités cliniques, radiologiques et thérapeutiques. Il s'agit de 5 patients dont l'âge moyen est de 34.6 ans (24-55). Le sexe ratio est de 1.5. Le principal motif de consultation était un syndrome douloureux de l'abdomen principalement au niveau de la fosse iliaque droite. L'examen abdominal montrait toujours une sensibilité localisée. La fièvre était présente chez 3 patients. Le bilan biologique révèle un syndrome inflammatoire biologique chez trois patients. Les examens complémentaires radiologiques en particulier échographie abdominale et TDM abdominale ont éliminé formellement une urgence chirurgicale et ont évoqué le diagnostic d'appendagite dans trois cas. Trois patients ont bénéficié d'une coelioscopie diagnostique confirmant le diagnostic  d'appendagite. L'évolution était favorable chez tous les patients. Les appendagites épiploïques primitives sont des étiologies rares et  sous-estimées de syndrome abdominal aigu. Le diagnostic peut être affirmé par imagerie notamment avec le scanner hélicoïdal injecté,  permettant d'instaurer ainsi un traitement médical premier et d'éviter un traitement chirurgical et des hospitalisations excessives

The emergence of the social brain network: evidence from typical and atypical development

Several research groups have identified a network of regions of the adult cortex that are activated during social perception and cognition tasks. In this paper we focus on the development of components of this social brain network during early childhood and test aspects of a particular viewpoint on human functional brain development: “interactive specialization.” Specifically, we apply new data analysis techniques to a previously published data set of event-related potential (ERP) studies involving 3-, 4-, and 12-month-old infants viewing faces of different orientation and direction of eye gaze. Using source separation and localization methods, several likely generators of scalp recorded ERP are identified, and we describe how they are modulated by stimulus characteristics. We then review the results of a series of experiments concerned with perceiving and acting on eye gaze, before reporting on a new experiment involving young children with autism. Finally, we discuss predictions based on the atypical emergence of the social brain network

Inhibition of Fungi and Gram-Negative Bacteria by Bacteriocin BacTN635 Produced by Lactobacillus plantarum sp. TN635

The aim of this study was to evaluate 54 lactic acid bacteria (LAB) strains isolated from meat, fermented vegetables and dairy products for their capacity to produce antimicrobial activities against several bacteria and fungi. The strain designed TN635 has been selected for advanced studies. The supernatant culture of this strain inhibits the growth of all tested pathogenic including the four Gram-negative bacteria (Salmonella enterica ATCC43972, Pseudomonas aeruginosa ATCC 49189, Hafnia sp. and Serratia sp.) and the pathogenic fungus Candida tropicalis R2 CIP203. Based on the nucleotide sequence of the 16S rRNA gene of the strain TN635 (1,540 pb accession no FN252881) and the phylogenetic analysis, we propose the assignment of our new isolate bacterium as Lactobacillus plantarum sp. TN635 strain. Its antimicrobial compound was determined as a proteinaceous substance, stable to heat and to treatment with surfactants and organic solvents. Highest antimicrobial activity was found between pH 3 and 11 with an optimum at pH = 7. The BacTN635 was purified to homogeneity by a four-step protocol involving ammonium sulfate precipitation, centrifugal microconcentrators with a 10-kDa membrane cutoff, gel filtration Sephadex G-25, and C18 reverse-phase HPLC. SDS-PAGE analysis of the purified BacTN635, revealed a single band with an estimated molecular mass of approximately 4 kDa. The maximum bacteriocin production (5,000 AU/ml) was recorded after a 16-h incubation in Man, Rogosa, and Sharpe (MRS) medium at 30 °C. The mode of action of the partial purified BacTN635 was identified as bactericidal against Listeria ivanovii BUG 496 and as fungistatic against C. tropicalis R2 CIP203

Gas injection in a liquid saturated porous medium. Influence of pressurization effects and liquid films

We study numerically and experimentally the displacement of a liquid by a gas in a two-dimensional model porous medium. In contrast with previous pore-network studies on drainage in porous media, the gas compressibility is fully taken account. The influence of the gas injection rate on the displacement pattern, breakthrough time and the evolution of the pressure in the gas phase due in part to gas compressibility are investigated. A good agreement is found between the simulations and the experiments as regards the invasion patterns. The agreement is also good on the drainage kinetics when the dynamic liquid films are taken into account

QTL Analysis of Shading Sensitive Related Traits in Maize under Two Shading Treatments

During maize development and reproduction, shading stress is an important abiotic factor influencing grain yield. To elucidate the genetic basis of shading stress in maize, an F2:3 population derived from two inbred lines, Zhong72 and 502, was used to evaluate the performance of six traits under shading treatment and full-light treatment at two locations. The results showed that shading treatment significantly decreased plant height and ear height, reduced stem diameter, delayed day-to-tassel (DTT) and day-to-silk (DTS), and increased anthesis-silking interval (ASI). Forty-three different QTLs were identified for the six measured traits under shading and full light treatment at two locations, including seven QTL for plant height, nine QTL for ear height, six QTL for stem diameter, seven QTL for day-to-tassel, six QTL for day-to-silk, and eight QTL for ASI. Interestingly, three QTLs, qPH4, qEH4a, and qDTT1b were detected under full sunlight and shading treatment at two locations simultaneously, these QTL could be used for selecting elite hybrids with high tolerance to shading and high plant density. And the two QTL, qPH10 and qDTS1a, were only detected under shading treatment at two locations, should be quit for selecting insensitive inbred line in maize breeding procedure by using MAS method

Pupillary Stroop effects

We recorded the pupil diameters of participants performing the words’ color-naming Stroop task (i.e., naming the color of a word that names a color). Non-color words were used as baseline to firmly establish the effects of semantic relatedness induced by color word distractors. We replicated the classic Stroop effects of color congruency and color incongruency with pupillary diameter recordings: relative to non-color words, pupil diameters increased for color distractors that differed from color responses, while they reduced for color distractors that were identical to color responses. Analyses of the time courses of pupil responses revealed further differences between color-congruent and color-incongruent distractors, with the latter inducing a steep increase of pupil size and the former a relatively lower increase. Consistent with previous findings that have demonstrated that pupil size increases as task demands rise, the present results indicate that pupillometry is a robust measure of Stroop interference, and it represents a valuable addition to the cognitive scientist’s toolbox

Mitochondrial ATP synthase: architecture, function and pathology

Human mitochondrial (mt) ATP synthase, or complex V consists of two functional domains: F1, situated in the mitochondrial matrix, and Fo, located in the inner mitochondrial membrane. Complex V uses the energy created by the proton electrochemical gradient to phosphorylate ADP to ATP. This review covers the architecture, function and assembly of complex V. The role of complex V di-and oligomerization and its relation with mitochondrial morphology is discussed. Finally, pathology related to complex V deficiency and current therapeutic strategies are highlighted. Despite the huge progress in this research field over the past decades, questions remain to be answered regarding the structure of subunits, the function of the rotary nanomotor at a molecular level, and the human complex V assembly process. The elucidation of more nuclear genetic defects will guide physio(patho)logical studies, paving the way for future therapeutic interventions