Effect of Water Stress on Photosynthetic Assimilation and Biomass Accumulation in Olive Tree

The climate change that we are attending in recent years requires a revision of the water resources management in order to en sure a sustainable supply. For this reason, in order to test the plants ability to face water stress, three water stress intensities (100% (T0), 50 (T1) and 25% (T2) field capacity (fc)), for 42 days in a greenhouse under semi-controlled conditions, were applied on 18 olive plants (Olea europaea L. cv 'Meski') of one year old. An evaluation of the response of the olive tree at different water supplies was conducted by monitoring the photosynthetic assimilation, chlorophyll index measured by SPAD, plant growth and dry matter accumulation. The results showed that photosynthesis has increased after 42 days for T0 plants while it increased during the first two weeks before dropping to the 42th day of the application of water restriction (AWR) for T1 plants; a decrease of 26% compared to control treatment. The photosynthetic assimilation of T2 plants has increased at a rate slower until the 28th day AWR then it has dropped after 42 days a decrease of 46% from the witness thus increasing the irrigation dose results in improved photosynthesis. The chlorophyll index fell 2, and 7% compared to the control treatment for T1 and T2, respectively, after 42 days AWR showing that fluid restriction affects the integrity of chlorophylls. Plant growth was shown by the development of a longer root for T2 plants ex plained by the search for minimum quantities of water available. The results showed that the control plants have accumulated more dry matter than stressed plants in the roots and the stem while the underground part/aerial part report seems indifferent to water stress. Water restriction has affected thereby biomass of roots and stems in favor of the leaves, the first operator of the photosyn thetic activit

Diastasis des grands droits avec nécrose cutanée sur une grossesse à terme

Les grossesses, à fortiori les grossesses multiples, engendrent des séquelles fonctionnelles et esthétiques majeures de la paroi abdominale. L'augmentation importante de la hauteur utérine a pour conséquence une distension musculaire et cutanée de l'étage sous ombilical et sus ombilical entraînant un défect musculoaponévrotique. Nous rapportons une observation exceptionnelle de nécrose cutanée avec diastasis des grands droits chez une femme âgée de 37 ans présentant un utérus bicicatriciel. L'évacuation utérine a été faite par césarienne à terme avec excision de la zone cutanée infectée et confection d'une plaque de Vicryl sous aponévrotique après avoir rapproché les deux muscles grands droits. La technique chirurgicale comprend: la résection cutanée et la plastie des muscles abdominaux. La résection cutanée consiste en une excision chirurgicale de tous les tissus nécrosés jusqu'aux fascias superficiels et profonds. La plastie musculaire est réalisée par des points inversés de rapprochement des muscles droits sur la ligne médiane. Les suites opératoires ont été simples. La grossesse peut être responsable dans de rares cas de séquelles pariétales. Toutefois, la durabilité du traitement chirurgicale reste à prouver, une récidive étant toujours possible.Pan African Medical Journal 2015; 2

Ecophysiological Responses of Two Olive Tree Cultivars (Olea europaea L. CV Koroneiki and Chemlali) Under Three Water Treatments

In this paper, our objective is to assess and compare the effects of three levels of irrigation application on the ecophysiological behavior and plant dry matter accumulation of two young olive tree cultivars Koroneiki, a promising greek cultivar, and Chemlali, the best local cultivar. According to this assessment, we can determine the most efficient water treatment that could be suitable for Mediterranean environments subjected to water shortage conditions. Measurements were made in the green house of the Tunisian Olive tree Institute under normal day-light conditions from March, 16th to April, 21st 2015. Three water treatments were applied which are T100% (control treatment: Daily irrigation at 100% of Available Water Content (AWC)), T50% (Daily irrigation at 50% of AWC) and T0% (Without watering). The results showed that the two olive tree cultivars possess important mechanisms to overtake limited water resources. However, some striking variations existed between the two cultivars studied. Indeed, as water stress increased (T0%), Chemlali maintained longer a high midday leaf water potential compared (- 4.54 MPa) to Koroneiki (- 5.8 MPa). T50% treatment seems to be sufficient for both cultivars. Measurements of total Osmotic Adjustment (OA) showed that olive trees use this mechanism to create very negative leaf water potentials in order to be able to extract water from a dry root environment. The root/shoot ratio of Chemlali plants at T50% treatment was the highest (1.08) comparatively with the other two treatments (0.70 and 0.79 for T100% and T0% AWC water treatments, respectively). This result shows that Chemlali plants valorize low quantities of water (T50%) rather than high quantities (T100%) and Koroneiki plants behave better when it is irrigated at 100% AWC. To conclude, Chemlali plants irrigated at 50% AWC, compared to Koroneiki plants, are the most suitable to tolerate water restriction conditions

West syndrome and mosaic trisomy 13: A case report

Trisomy 13, or Patau syndrome, is a rare chromosomal disorder characterized by a triad of cleft lip and palate, postaxial polydactyly, and microphthalmia, with an incidence ranging between 1/5,000 and 1/20,000 births.1 Most patients (80%) with Patau syndrome have complete trisomy 13. Mosaic trisomy 13 is very rare; it occurs in only 5% of all patients with the trisomy 13 phenotype.2 Trisomy 13 is a clinically severe entity, and 90 to 95% of patients born with this syndrome do not survive beyond one year of life. However, patients with mosaic trisomy 13 usually have longer survival and less severe phenotype compared to patients with complete trisomy 13. Malformations mainly affect midline development, with a high frequency of central nervous system involvement. The presence of central nervous system malformations is important as a predictive factor of survival.1,3 It is well known that the incidence of epilepsy is higher in children with Patau syndrome than in the general population, and West syndrome or infantile spasms have been rarely reported in these children.1,4,5 Prior to our report, there has been no case report of West syndrome associated with mosaic trisomy 13. The association of West syndrome with trisomy 13 is considered a symptomatic West syndrome because of preexisting psychomotor development delay and the poor prognosis in most of these children.6 We report here the first case of West syndrome in a girl with mosaic trisomy 13 and discuss the clinical characteristics and prognosis of this association

Estimation of the economic impact of a bluetongue serotype 4 outbreak in Tunisia

IntroductionSince 1999, Tunisia has experienced multiple occurrences of Bluetongue (BT) outbreaks, leading to numerous reported cases of infection and mortality in flocks. The re-emergence of the disease in 2020 caused substantial economic losses in cattle, attributed to the incursion of serotype BTV-4.MethodsTo evaluate the economic impact of the recent BT episode, we conducted a retrospective study on outbreaks that occurred in Tunisia between August and November 2020, focusing on the impact at the owner’s level and its effects on both small ruminants and cattle. A total of 234 ruminant farms (sheep, cattle, and mixed) were randomly selected across Tunisian governorates and included in the study to estimate both the direct and indirect costs of these outbreaks.ResultsTotal costs were calculated as the sum of losses and expenditures resulting from the BT outbreaks. At the animal level, total losses were estimated to range between 116.280 and 207.086 TND for one infected ewe (€33.721 and 60.055). For one lactating cow, costs varied between 2,590.724 and 3,171.107 TND (€751.310 and 919.621). In cattle, exposure to BTV led to a daily unit milk yield decrease of 12.50 to 14.66 L over an average period of 5 months. Diseased sheep experienced weight loss ranging between 4 and 10 kg during the BT outbreaks. The total mean cost of the 2020 BT outbreak in Tunisian investigated farms was estimated at 1,935 million TND (million €561.15) (range: 1,489 and 2,474 million TND; 431.81 and million €717.46). The most influential costs of the total BT outbreaks were the decrease in milk yield, mortality, and veterinary treatment.DiscussionThis study gives valuable insights on the economic impact of the incursion of a new serotype of BT in a naive population in Tunisia. Considering the substantial costs incurred, it is imperative that this disease receives increased attention from stakeholders, including animal owners, veterinary services, practitioners, and decision-makers

Contribution de la microscopie électronique à la compréhension des mécanismes de vieillissement des matériaux de batteries lithium-ion associées aux énergies renouvelables

Le travail présenté dans cette thèse s'inscrit dans le cadre du projet ANR VISION (Etude fine des mécanismes de Vieillissement des batteries Li-ION associées aux énergies renouvelables). Tout un arsenal de techniques de microscopies, allant d'observations à l'échelle micrométrique (MEB) jusqu’à l'échelle atomique (METHR, HR-HAADF) couplées à des techniques spectroscopiques (Microanalyse X et perte d'énergie des électrons), a été mis en oeuvre afin d'identifier les différents modes de dégradations des batteries vieillies sous une des sollicitations électrochimiques très importantes. Les accumulateurs Li-ion étudiés utilisent des matériaux Li[Ni1-x-yMnxCoy]O2 (NMC) pour l'électrode positive et du carbone graphitisé pour l'électrode négative. Nos études ont permis, non seulement de visualiser et de mieux comprendre les modes de dégradation des batteries stationnaires SAFT, mais également d'utiliser des techniques innovantes de microscopie (telles le HR-HAADF ou bien encore la tomographie FIB) afin de révéler la texture et la structure de la matière active avant et/ou après cyclage. Parallèlement, une étude plus fondamentale sur des matériaux modèles (Li2Ru1-ySnyO3…) présentant des propriétés structurales et électrochimiques similaires aux matériaux utilisés dans des batteries commerciales, a été réalisée. Au travers de cette étude, des sur-structures ont pu être observées lors du cyclage et le rôle de l'oxygène dans les processus redox, qui sont derrière la grande capacité délivrée par les composites riches en lithium (tels que : Li2MnO3-LiMO2, M = Ni, Co…), a pu être discutéThe work presented in this thesis is part of the ANR project VISION (fine Study of the Aging mechanisms Battery Li-ION associated with renewable energy). An arsenal of electron microscopy techniques allowing to do observations from the micrometer scale (SEM) to the atomic scale (HRTEM, HR-HAADF) coupled with spectroscopic techniques (X microanalysis and electron energy loss) has been implemented to identify the aging processes occurring in long cycled Li-ion batteries. The so-studied Li-ion batteries are using Li[Ni1-x-yMnxCoy]O2 (NMC) and graphitic carbon as positive and negative electrode materials, respectively. These studies allowed us, not only, to visualize and obtain a better understanding in the degradation modes in SAFT stationary batteries but also to perform innovative microscopy techniques (such HR-HAADF or FIB tomography) in order to reveal the texture and the structure of the active materials. In the same way, a fundamental study on model materials (Li2Ru1-ySnyO3…), having structural and electrochemical properties similar materials used in commercial batteries, has been achieved. Through this study, superstructures were observed, by TEM, during the cycling and the role of oxygen in redox processes, which are behind the high capacity delivered by the lithium-rich composites (such as: Li2MnO3-LiMO2, M = Ni, Co…), has been discusse

Étude asymptotique et numérique d’inclusions fines dans des domaines élastiques

This work focused on mathematical modeling and numerical approximation of the influence of a very thin inclusion on an elastic substrate of different stiffness. The study is motivated by applications in tires and is not based on conventional homogenization techniques. Indeed, the objective was to treat the interaction between a single inclusion and its elastic medium and not a density of inclusions. The study consisted of three parts, the first concerning mathematical modeling for linear behavior laws leading to an expression of the contribution of the inclusion in the form of the inclusion-free field corrected by correctors at different orders. These correctors are independent of the characteristic size of the inclusion. The second relates to the numerical approximation of this influence by means of the finite element method and that of the inverted finite elements. A numerical strategy for taking into account the influence of several inclusions is also presented. The last part is prospective and discusses the possibility of extending the approach for nonlinear behavioral laws.Ce travail de thèse a concerné la modélisation mathématique et l’approximation numérique de l’influence d‘une inclusion très fine sur un substrat élastique de différente rigidité. L’étude est motivée par les applications dans les pneumatiques et ne se base pas sur des techniques d’homogénéisation classiques. En effet, l’objectif a été de traiter l’interaction entre une seule inclusion et son milieu élastique et non une densité d’inclusions. L’étude a comporté trois volets, le premier concernant une modélisation mathématique pour des lois de comportement linéaires aboutissant à une expression de la contribution de l’inclusion sous la forme du champ sans inclusion corrigé par des correcteurs à différents ordres. Ces correcteurs sont indépendants de la taille caractéristique de l’inclusion, Le second a concerné l’approximation numérique de cette influence moyennant la méthode des éléments finis et celle des éléments finis inversés. Une stratégie numérique de prise en compte de l’influence de plusieurs inclusions y est aussi présentée. Le dernier volet est prospectif et discute de la possibilité de l’extension de l’approche pour des lois de comportement non linéaires

Asymptotic and numerical study of fine inclusions in elastic domains

Ce travail de thèse a concerné la modélisation mathématique et l’approximation numérique de l’influence d‘une inclusion très fine sur un substrat élastique de différente rigidité. L’étude est motivée par les applications dans les pneumatiques et ne se base pas sur des techniques d’homogénéisation classiques. En effet, l’objectif a été de traiter l’interaction entre une seule inclusion et son milieu élastique et non une densité d’inclusions. L’étude a comporté trois volets, le premier concernant une modélisation mathématique pour des lois de comportement linéaires aboutissant à une expression de la contribution de l’inclusion sous la forme du champ sans inclusion corrigé par des correcteurs à différents ordres. Ces correcteurs sont indépendants de la taille caractéristique de l’inclusion, Le second a concerné l’approximation numérique de cette influence moyennant la méthode des éléments finis et celle des éléments finis inversés. Une stratégie numérique de prise en compte de l’influence de plusieurs inclusions y est aussi présentée. Le dernier volet est prospectif et discute de la possibilité de l’extension de l’approche pour des lois de comportement non linéaires.This work focused on mathematical modeling and numerical approximation of the influence of a very thin inclusion on an elastic substrate of different stiffness. The study is motivated by applications in tires and is not based on conventional homogenization techniques. Indeed, the objective was to treat the interaction between a single inclusion and its elastic medium and not a density of inclusions. The study consisted of three parts, the first concerning mathematical modeling for linear behavior laws leading to an expression of the contribution of the inclusion in the form of the inclusion-free field corrected by correctors at different orders. These correctors are independent of the characteristic size of the inclusion. The second relates to the numerical approximation of this influence by means of the finite element method and that of the inverted finite elements. A numerical strategy for taking into account the influence of several inclusions is also presented. The last part is prospective and discusses the possibility of extending the approach for nonlinear behavioral laws

Film réalisé par Daniel Bay - Titre "Le COPEAU en Tunisie"

Le projet de Réseau de COntrôle de la Pollution de l'EAU est financé par la Commission Européenne, dans le cadre du programme LIFE Pays Tiers. Par l'implication de l'Aquapôle, il vise à renforcer l'Agence Nationale de Protection de l'Environnement (ANPE), bénéficiaire du projet, dans sa mission de contrôle de pollution des eaux et de coordination de la surveillance et du contrôle de la qualité des eaux continentales (eaux de surface et eaux souterraines) en Tunisie