Une cataracte inhabituelle: régressive à noyau pétaloïde

Nous rapportons le cas d'une patiente de 38 ans, sans antécédents médico-chirurgicaux, victime d'un traumatisme contusif de l'œil droit par coup de pierre il y a 20 ans, avec baisse de l'acuité visuelle progressive depuis 10 ans. L'examen ophtalmologique note au niveau de l'œil droit une acuité visuelle à mouvement des doigts, et un tonus oculaire à 11mmHg. L'examen du segment antérieur après dilatation objective une cataracte régressive, dont le noyau présumé est de forme pétaloïde, les bords et les sutures des pétales sont denses. Une échographie oculaire est réalisée vu l'inaccessibilité du fond d'œil, ainsi que l'examen de l'œil gauche n'objective aucune anomalie

Analysis of Potential Production in Morocco

In recent years, economic developments in a number of advanced and developing countries have been marked by a decline in growth. Many studies have shown that a large part of this depreciation is explained by that of potential growth. In this respect, the development of potential growth has become one of the most important economic issues in that it affects the conduct of monetary policy and the management of public finances. The objective of this article is to propose an estimate of potential output in Morocco, based on econometric modeling of the Cobb Douglass function based on three variables: Real Gross Domestic Product (GDP), Capital Stock (K) and employment level (L). Using annual data covering the period from 1982 to 2019, representing a sample of 38 observations. The results obtained show a decrease in potential output in Morocco from 2011 onwards, mainly due to the slowdown in the rate of change of GFCF to 3.8% on average between 2011 and 2019, the declining employment rate and also the negative contribution of overall factor productivity. From the results of this study it would be possible to determine the output gap, that is, the gap between actual and potential output. The latter is an important variable for the conduct of monetary policy, as it is a major source of inflationary pressures in the economy.   JEL Classification : E00, E23, D2, D24 Paper type: Empirical researchIn recent years, economic developments in a number of advanced and developing countries have been marked by a decline in growth. Many studies have shown that a large part of this depreciation is explained by that of potential growth. In this respect, the development of potential growth has become one of the most important economic issues in that it affects the conduct of monetary policy and the management of public finances. The objective of this article is to propose an estimate of potential output in Morocco, based on econometric modeling of the Cobb Douglass function based on three variables: Real Gross Domestic Product (GDP), Capital Stock (K) and employment level (L). Using annual data covering the period from 1982 to 2019, representing a sample of 38 observations. The results obtained show a decrease in potential output in Morocco from 2011 onwards, mainly due to the slowdown in the rate of change of GFCF to 3.8% on average between 2011 and 2019, the declining employment rate and also the negative contribution of overall factor productivity. From the results of this study it would be possible to determine the output gap, that is, the gap between actual and potential output. The latter is an important variable for the conduct of monetary policy, as it is a major source of inflationary pressures in the economy.   JEL Classification : E00, E23, D2, D24 Paper type: Empirical researc

Plasmonic-Assisted Water–Gas Shift Reaction of Gold Particles on TiO₂

The Localized Surface Plasmon (LSP) effect of 5 nm mean size Au particles deposited on TiO2 P25 was investigated during the photo-thermal water gas shift reaction (WGSR). The effects of CO concentration, excitation light flux and energy, and molecular oxygen addition during the reaction were investigated. The photocatalytic WGSR rate under light excitation with wavelengths extending from 320 to 1100 nm was found to be higher than the thermal reaction alone at the same temperature (85 °C). A H2/CO2 ratio of near unity was found at high concentrations of CO. The addition of molecular oxygen during the reaction resulted in a slight decrease in molecular hydrogen production, while the rates of CO2 formation and CO consumption changed by one order of magnitude. More importantly, it was found that the WGSR rates were still high under only visible light excitation (600–700 nm). The results prove that Au LSP alone triggers this chemical reaction without requiring the excitation of the semiconductor on which they are deposited

Optimisation d'un procédé de pyrolyse en four tournant : application à la production de charbons actifs

Les charbons actifs sont utilisés dans de nombreux procédés comme le traitement de l'eau, la séparation des gaz, la réfrigération par voie solaire ou encore le stockage de gaz comme l'hydrogène ou le méthane. Le four tournant est utilisé dans l'industrie pour produire des charbons actifs. Une étude d'optimisation de la production de charbons actifs en four tournant est présentée. La pyrolyse a d'abord été étudiée dans le domaine de température [30-800˚C]. Une identification des paramètres cinétiques a été effectuée sur la base des expériences réalisées en TG. Des expériences ont été conduites également en réacteur à lit traversé pour analyser la formation de la surface spécifique des charbons actifs. Il a été montré qu'une température de 450 ˚C et une durée de pyrolyse de 30 minutes permettent d'obtenir une surface spécifique maximale de 1477 m2/g. Un modèle 1D est proposé à l'échelle du four tournant. Il permet de calculer les évolutions des débits massiques des espèces, des températures du lit de particule, de la phase gaz et de la paroi du four tournant, ainsi que la surface spécifique des charbons actifs. Un code d'optimisation non-linéaire a été couplé au modèle de four tournant. Un profil de température de paroi non trivial qui maximise la surface spécifique des charbons actifs en sortie de four tournant a été déterminé par ce code. ABSTRACT : Activated carbons are used in many applications such as water treatment, separation of gases, solar refrigeration or gas storage like hydrogen or methane. Rotary kiln is used in industry to produce activated carbon. A study on the optimization of the production of activated carbon in a rotary kiln is presented. Pyrolysis process is examined by using TG experiments in the temperature range [30-800˚C]. Kinetic parameters are proposed on the basis of those TG experiments. Laboratory experiments are also conducted in a crossed bed reactor in order to determine kinetics formation of the specific surface area of activated carbons. Those experiments show that a temperature of 450˚C and a time duration of pyrolysis of 30 minutes lead to a optimal specific surface of 1477 m2/g. A 1D model of the heated rotary kiln is developed. The model is able to compute mass flow rates of species, temperatures of bed, gas phase and kiln wall, and finally specific surface area of activated carbons. The model of the rotary kiln is finally coupled to a non linear optimization software. An optimal thermal profile of the kiln that maximises the specific surface area of the solid at the exit of the kiln is computed

Implementation of a Sustainable Security Architecture using Radio Frequency Identification (RFID) Technology for Access Control

Implementation of a sustainable security architecture has been quite a challenging task with several technology deployed to achieve the feat. Automatic IDentification (Auto-ID) procedures exist to provide information about people, animals, goods and products in transit and found several applications in purchasing and distribution logistics, industries, manufacturing companies and material flow systems. This work focuses on the development and implementation of an access control system using Radio Frequency Identification (RFID) technology to enhance a sustainable security architecture. The system controls access into a restricted area by granting access only to authorized persons, which incorporates the RFID hardware (RFID tags and readers and their antennas) and the software. The antenna are to be configured for a read range of about 1.5 m and TMBE kit reader module was used to test the RFID tags. The encoding and decoding process for the reading and writing to the tag as well as interfacing of the hardware and software was achieved through the use of a FissaiD RFID Reader Writer. The software that controls the whole system was designed using in Java Language. The database required for saving the necessary information, staff/guest was designed using appropriate DataBase Management System (DBMS). The system designed and implemented provide records of all accesses (check-in and check-out) made into the restricted area with time records. Other than this system, Model based modeling through the MATLAB/Simulink, Arduino platform, etc. can be used for similar implementation.Comment: Presented at the 19th Annual National Conference of the School of Business Studies, Federal Polytechnic, Ede, 11 pages, 10 figure

Débat théorique sur le choix du régime de change : Retour sur l’opposition fixe-flexible

The choice of the exchange rate regime occupies an important place in contemporary economics because of the role that the exchange rate plays in the management of economic policy as a tool for decision-making. The literature and empirical studies show the existence of correlations between the exchange rate regime, inflation, economic growth and crises. The optimal exchange rate regime depends on the study of the effect of the exchange rate on macroeconomic variables, which differ from country to country depending on economic policy, the size and strength of the state, in addition to the long-term impact related to structural competitiveness and the dynamics of the real exchange rate and its relationship with the cost of production (wages, technological development) and external competitiveness. The choice of the exchange rate regime is an important theoretical issue in international finance. Based on a review of the theoretical debate on the choice between fixed, floating and intermediate exchange rate regimes, this paper argues that the choice of the exchange rate regime is a dynamic system influenced by a variety of factors and variables, and that the choice of the exchange rate regime is a matter of discretionary choice in the specific circumstances of a country. The most important aspect of an exchange rate regime is its degree of flexibility. The issue is more complex than a simple choice between fixed and floating exchange rates. The importance of the study lies in the fact that the problem of the optimal exchange rate regime is one of the complex and modern problems related to international finance, which requires many studies to understand and provide solutions necessary to ensure the best economic performance. The objective of this article is to take a theoretical look at the factors explaining the choice of the exchange rate regime.     JEL Classification : F3. Paper type : Theoretical Research.Le choix du régime de change occupe une place importante dans l'économie contemporaine en raison du rôle que joue le taux de change dans la gestion de la politique économique en tant qu'outil d’aide à la décision. La littérature et les études empiriques montrent l’existence des corrélations entre le régime de change, l'inflation, la croissance économique et les crises. Le régime de change optimal dépend de l'étude de l'effet du taux de change sur les variables macroéconomiques, qui diffèrent d'un pays à l'autre en fonction de la politique économique, de la taille et de la force de l'État, en plus de l'impact à long terme lié à la compétitivité structurelle et à la dynamique du taux de change réel et sa relation avec le coût de production (salaires, développement technologique) et la compétitivité externe. Le choix du régime de change est une question théorique importante dans le domaine de la finance internationale. Sur la base d'un examen du débat théorique sur le choix entre les régimes de change fixe, flottant et intermédiaire, ce document soutient que le choix du régime de change est un système dynamique influencé par une variété de facteurs et de variables, et que le choix du régime de change est une question de choix discrétionnaire dans les circonstances spécifiques d'un pays. L'aspect le plus important d'un régime de taux de change est son degré de flexibilité. La question est plus complexe qu'un simple choix entre taux de change fixe et taux flottant. L'importance de l'étude réside dans le fait que le problème du régime de change optimal est l'un des problèmes complexes et modernes liés à la finance internationale, qui nécessite de nombreuses études pour comprendre et apporter des solutions nécessaires pour assurer les meilleures performances économiques. L’objectif du présent article est de porter un regard théorique pour pouvoir examiner les facteurs expliquant le choix du régime de change.     Classification JEL : F, F3. Type de l’article : article théorique

Wang Koch-adjusted axial length in SRK/T formula for ocular biometry in high myopia: a prospective study

Background: The aim of this study was to prospectively assess refractive results of cataract surgery in highly myopic eyes using the SRKT formula and Wang Koch-adjusted axial length. Material and methods: Prospectively, we recruited consecutive candidates for cataract surgery having an axial length equal to 27 mm and longer. We performed biometry by using Wang and Koch-adjusted axial length applied to the SRKT formula. The main outcome measures were: mean of refractive error, mean of absolute refractive error, and percentage of eyes that achieved a refractive error of ± 0.5D and ± 1D. Results: Fifteen eyes of nine patients were involved in the study. The mean refractive error was -0.01D ± 0.4D, and the mean absolute refractive error was + 0.35D ± 0.20D. Refractive errors of ± 0.5D and ± 1D were achieved, respectively, in 86.6% and in 100% of eyes. Conclusions: Wang Koch’s axial length adjustment applied to the SRKT formula is a reliable alternative in high myopic cataract patients