ADSORPTION KINETICS OF AN CATIONIC DYE FFROM AQUEOUSE SOLUTION BY ALGERIAN MINERAL MATERIALS

AbstractThe objective of this study is to determine the power of two algerian mineral materials (kaolin and diatomite ) ,in order to remove an cationic dye(methylene blue )from aqueous solution ,materials have been characterized by different techniques .experiments have been studied on bath mode ,the influence of some parameters had been studied , such as , contact time ,the pH of solution and initial concentration .kinetics show that adsorption of methylene blue on to diatomite is faster than processus of adsorption on to kaoln ,and can be demonstrated by the  pseudo-second –order model. Diatomite and kaolin used in this study improve their efficiency on elimination of methylene blue and could be low-cost alternative materials.

Approaches that will yield greater success when implementing self-administered electronic data capture ICT systems in the developing world with an illiterate or semi-literate population

The Information Technology (IT) Group at the Population Council responded to a need for a technology solution that would help researchers obtain more accurate responses to survey questions that concerned subject matter of a sensitive nature. The IT Group had three goals: (1) to enhance research by obtaining the best data possible, (2) to operate successfully in the local environment and be welcomed by the local populations, and (3) to increase the efficiency and cost-effectiveness of the survey process. This paper outlines approaches to consider when designing and implementing self-administered information and communications technology (ICT) questionnaires in developing countries, and reviews the problems and issues we encountered and how we overcame them. Many of the approaches outlined may also be used in general for ICT-related projects in the developing world. To meet future challenges, we have begun an effort to build a prototype system that would operate on a variety of devices—when connected to the internet or not (securely storing the data when the system is offline)—and provide an administrative application to step through simple screens to build a self-administered questionnaire with the most frequently used functions

Role of oxygen exposure on the differentiation of human induced pluripotent stem cells in 2D and 3D cardiac organoids

Introduction Human induced pluripotent stem cells (hiPSC) have the ability to differentiate theoritically into any cell type. The development of organoid systems exhibiting the essential features of human organ such as liver and heart is of high interest. Optimizing the culture conditions to obtain the highest cardiac organoids efficacy is crucial. In fact, cardiac differentiation protocols have been established by essentially focusing on specific growth factors on hiPSC differentiation efficiency. However, the optimal environmental factors such as the optimal oxygen exposure to obtain cardiac myocytes in network are still unclear. The mesoderm germ layer differentiation is known to be enhanced by low oxygen exposure. Yet, the effect of low oxygen exposure on the molecular and functional maturity of the hiPSC-derived cardiomyocytes remains unexplored. Aims We aimed here at comparing the molecular and functional consequences of low (5% O2 or LOE) and high oxygen exposure (21% O2 or HOE) on cardiac differentiation of hiPSCs in 2D monolayer and 3D organoids protocols. Methods hiPSC-CMs were differentiated through both the 2D (monolayer) and 3D (embryoid body) protocols using several lines. Cardiac marker expression and cell morphology were assessed using qRT-PCR and immunofluorescence. The mitochondrial localization and metabolic properties were evaluated by high-resolution respirometry and mitochondrial staining. The intracellular Ca2+ handling and contractile properties were also monitored using confocal fluorescent microscopy and atomic force microscopy. Results Our results indicated that the 2D cardiac monolayer can only be differentiated in HOE. The 3D cardiac organoids containing hiPSC-CMs in LOE exhibited higher cardiac markers expression such as troponin T (TnTc), RyR2, Serca2a, alpha and beta heavy myosin chains. Moreover, we found enhanced contractile force, hypertrophy and steadier SR Ca2+ release reflected by a more regular spontaneous Ca2+ transients associated with a higher maximal amplitude and lower spontaneous Ca2+ events revealing a better SR Ca2+ handling in LOE. Similar beat rate, preserved distribution of mitochondria and similar oxygen consumption by the mitochondrial respiratory chain complexes were also observed. Conclusions Our results brought evidences that LOE is moderately beneficial for the 3D cardiac organoids with hPSC-CMs exhibiting further maturity. In contrast, the 2D cardiac monolayers strictly require HOE.Introduction Human induced pluripotent stem cells (hiPSC) have the ability to differentiate theoritically into any cell type. The development of organoid systems exhibiting the essential features of human organ such as liver and heart is of high interest. Optimizing the culture conditions to obtain the highest cardiac organoids efficacy is crucial. In fact, cardiac differentiation protocols have been established by essentially focusing on specific growth factors on hiPSC differentiation efficiency. However, the optimal environmental factors such as the optimal oxygen exposure to obtain cardiac myocytes in network are still unclear. The mesoderm germ layer differentiation is known to be enhanced by low oxygen exposure. Yet, the effect of low oxygen exposure on the molecular and functional maturity of the hiPSC-derived cardiomyocytes remains unexplored. Aims We aimed here at comparing the molecular and functional consequences of low (5% O2 or LOE) and high oxygen exposure (21% O2 or HOE) on cardiac differentiation of hiPSCs in 2D monolayer and 3D organoids protocols. Methods hiPSC-CMs were differentiated through both the 2D (monolayer) and 3D (embryoid body) protocols using several lines. Cardiac marker expression and cell morphology were assessed using qRT-PCR and immunofluorescence. The mitochondrial localization and metabolic properties were evaluated by high-resolution respirometry and mitochondrial staining. The intracellular Ca2+ handling and contractile properties were also monitored using confocal fluorescent microscopy and atomic force microscopy. Results Our results indicated that the 2D cardiac monolayer can only be differentiated in HOE. The 3D cardiac organoids containing hiPSC-CMs in LOE exhibited higher cardiac markers expression such as troponin T (TnTc), RyR2, Serca2a, alpha and beta heavy myosin chains. Moreover, we found enhanced contractile force, hypertrophy and steadier SR Ca2+ release reflected by a more regular spontaneous Ca2+ transients associated with a higher maximal amplitude and lower spontaneous Ca2+ events revealing a better SR Ca2+ handling in LOE. Similar beat rate, preserved distribution of mitochondria and similar oxygen consumption by the mitochondrial respiratory chain complexes were also observed. Conclusions Our results brought evidences that LOE is moderately beneficial for the 3D cardiac organoids with hPSC-CMs exhibiting further maturity. In contrast, the 2D cardiac monolayers strictly require HOE

An Adaptive QoE‐Based Network Interface Selection for Multi‐homed eHealth Devices

International audienceConventional network control mechanisms are no longer suitable for Internet of Things (IoT) because they don’t allow scalability with a guarantee of Quality of Experience (QoE) especially when it comes to the health sector characterized by its real time and critical life aspects. That’s why we need to think differently about control. One aspect consists of improving the network accessibility by considering Multi-homed terminals using multiple network access points simultaneously. In this paper we present a new Q-Learning-based adaptive network interface selection approach. Experimental results show that the proposed approach involve QoE compared to a simple linear programming approach. abstract environment

An Adaptive Real Time Mechanism For IaaS Cloud Provider Selection based on QoE aspects

International audienceTraditionally, companies host their own services, platforms and infrastructures on their own servers. This policy results in high costs in terms of material and human resources. It may also be inadequate to the real needs of the company. In this context, one solution is to use cloud computing to outsource their services. The latter is defined by making available to the customer high-performance servers and high bandwidth. The cloud is also defined by renting software and hardware infrastructure to customers according to their needs. Cloud computing is made possible by the improvement of computer networks infrastructures. Indeed, broadband connections have reduced latency and thus enabled the use of remote resources. The success of cloud computing has led to a significant increase in the providers number offering many and varied cloud services. While the access to these services is made possible through a simple subscription, no technique is currently available to select the cloud provider that best fits their needs. Selecting a provider is an optimization problem that has been studied in several areas. Given the large number of parameters and actors in the cloud, this problem is known as NP-complete one. In this work, we propose a new developed platform which plays the role of a broker between clients and cloud providers. Based on a set of benchmark tasks on provider services, it performs an adaptive cloud provider selection in accordance with the client needs. The experimental results show that the proposed approach gives benefits to subscribers in terms of QoE

Intravenous human mesenchymal stem cells transplantation in NOD/SCID mice preserve liver integrity of irradiation damage

This work was initiated in an effort to evaluate the potential therapeutic contribution of the infusion of mesenchymal stem cells (MSC) for the correction of liver injuries. We subjected NOD-SCID mice to a 10.5-Gy abdominal irradiation and we tested the biological and histological markers of liver injury in the absence and after infusion of expanded human MSC. Irradiation alone induced a significant elevation of the ALT and AST. Apoptosis in the endothelial layer of vessels was observed. When MSC were infused in mice, a significant decrease of transaminases was measured, and a total disappearance of apoptotic cells. MSC were not found in liver. To explain the protection of liver without MSC engraftment, we hypothesize an indirect action of MSC on the liver via the intestinal tract. Pelvic or total body irradiation induces intestinal absorption defects leading to an alteration of the enterohepatic recirculation of bile acids. This alteration induces an increase in Deoxy Cholic Acid (DCA) which is hepatoxic. In this study, we confirm these results. DCA concentration increased approximately twofold after irradiation but stayed to the baseline level after MSC injection. We propose from our observations that, following irradiation, MSC infusion indirectly corrected liver dysfunction by preventing gut damage. This explanation would be consistent with the absence of MSC engraftment in liver. These results evidenced that MSC treatment of a target organ may have an effect on distant tissues. This observation comes in support to the interest for the use of MSC for cellular therapy in multiple pathologies proposed in the recent years. © 2012 Springer Science+Business Media, LLC