Design and implementation of a Context-Aware Health Service Platform (CAHS)

Computers are no match to humans in deducing situational information from their environment and in using it in their interactions. The advent of the context-aware applications seems to offer a way out to the computer that is not context-sensitive. The context aware applications can adapt their behaviors according to the perceived context or situation, without explicit user intervention, thereby providing human-centric services. To simplify the complexity of developing applications, context aware framework, which introduces context awareness into the environment where the applications are executed, is highlighted to provide a homogeneous interface involving generic context management and adaptation solutions. This papier has focused on the design of Context-Aware Health Services (CAHS) platform, which provide a health applications framework embedded on mobile devices. Our proposed platform is capabilities for context manager and adaptations according to context changes. It is designed to base on the SOA principles for achieving a flexible and dynamic architecture

Hydration and rheology of sulfoaluminate cements (CSA) in presence of polycarboxylate superplasticizers (PCE) and citric acid

ISSN: 2523-935XInternational audienceIt is admitted that the cement industry contributes for about 5-7% of the total man-made CO2 emissions. A possible way for decreasing these CO2 emissions is the development of alternative clinkers with lower proportion of limestone in the raw materials. Calcium sulfoaluminate cements (CSA) are regarded as a promising low CO2 alternative to Portland cements. Generally, with a sufficient amount of calcium sulfates, the main hydration product of these cements is ettringite, which strongly affects the workability of CSA pastes. Polycarboxylate superplasticizers (PCE), combined with retarders, can be used with the aim to decrease the yield stress and the viscosity of this type of pastes. However, the multitude of components of these cements makes it difficult to understand the effect of these additives on the hydration process and on the properties of pastes. The aim of this work is to provide a better understanding of the: (i) effect of the molecular structure and the dosage of PCE on the hydration and rheology of CSA (ii) effect of citric acid on the dispersing effectiveness of PCE . Three PCEs, with the same chemical structure but different molecular structure, were investigated. Vicat tests and isothermal calorimetry were used to describe the hydration process. While, Rheological properties were characterized with mini-cone tests. Adsorption measurements were carried out with Total Organic Carbon analyzer and ion chromatography. The results reveal a competitive adsorption between citric acid and PCEs, which decreases the dispersing effectiveness of the latter

Starch digestion in pearl millet (<i>Pennisetum glaucum</i> (L.) R. Br.) flour from arid area of Algeria

To assess the nutritive value of minor cereals cultivated in arid areas of Algeria, nine pearl millet landraces were sampled from two regions: Tidikelt and Hoggar. Some qualitative and quantitative characters of the panicle and grain were measured, as well as in vitro starch digestion of the grain flour. Considerable variation was recorded in seed color, endosperm texture and nutritional value of starch and protein content. In vitro starch digestion displayed a first-order kinetic model. For all pearl millet landraces, starch was digested to a different extent; the hydrolysis index (HI) ranged from 22.29% to 35.52% and the expected glycemic index (eGI) ranged from 27.41 to 38.82. The results show that there is diversity in the physical and chemical properties of pearl millet accessions from the arid areas of Algeria: Tidikelt and Hoggar. This study confirms that pearl millet has an acceptable nutritional value with a low glycemic index suitable for human health and nutrition

Influence of polycarboxylate superplasticizer, citric acid and their combination on the hydration and workability of calcium sulfoaluminate cement

International audiencePCEs are well known to improve the initial fluidity of CSA. However, their dispersion efficiency drops quickly over time. This issue can be solved by incorporating retarders. In this context, this paper deals with the influence of citric acid, used as a retarder, PCE and their combination on the hydration and workability of CSA. Isothermal calorimetry, XRD and TG analysis were used to describe the hydration process, while workability was characterized with the mini-cone test. Adsorption behavior was investigated using total organic carbon analyzer coupled with ion chromatography. Results show that the introduction of citric acid retained the dispersion efficiency of PCE over time. However, the initial dispersion efficiency of PCE was decreased by citric acid as the latter tend to adsorb first on the surface of cement grains, inhibiting the adsorption of PCE. A dispersion model was proposed to describe the acting mechanism of these admixtures on CSA

Effect of different retarders and their combination with superplasticizer on the properties of CSA

International audienceThe aim of this work was to investigate the effect of polycarboxylate type superplasticizers (PCE), and three different retarders (citric acid, tartaric acid, potassium gluconate) and their combination on hydration process and rheological properties of CSA at early age. The hydration process was described through isothermal calorimetry, while the rheological properties were characterized through yield stress of cement pastes determined by rheometry. The results show that gluconate is the most powerful retarder, followed by tartaric acid, then citric acid. PCE strongly improves the fluidity of the pastes but a rapid loss of workability is noticed. On the contrary, retarders slightly decrease the yield stress of the pastes but slowdown the loss of fluidity. The combination of the both admixtures allows to maintain high fluidity for longer time. However, for citric acid, and even more for tartaric acid, a rheological instability, characterized by a decrease followed by an increase in the yield stress over time, is noticed. Potassium gluconate seems to be the best retarder to combine with PCE since no instability and longer maintenance of workability were observed. An optimum dosage, leading to the best initial fluidity to the pastes, was also determined for the three retarders. The rheological results are related to the delay induced by the retarder on the hydration products formation for the first hours of hydration and to competitive adsorption between retarder and PCE

In vitro starch digestibility of by-products of sorghum starch extraction

The aim of the present study was to assess the nutritive value of by-products of sorghum starch extraction, as dietary starch from feed grains. Five by-products differing in their particle sizes and starch contents were collected. The mean values of fraction yields and starch contents, for first, second and third fraction of sorghum gluten feed were respectively 16.13 – 52.63 %, 01.97 – 44.08 % and 04.99 – 56.75 %, while for sorghum gluten meal the values were 22.27 – 71.13 %. The substrates from whole grain meal, prepared by dry milling, and from by-products differed in their in vitro starch digestion. The mean values for kinetic parameters ranged from 0.0066 to 0.0147 min-1 for the rate constant (k), from 53.66 to 98.58 % for the starch hydrolysis at infinite time (C∞) and from 6.06×103 to 8.47×103 %.min for the area under the hydrolysis curve (AUC). Generally, a high digestibility of by-products of sorghum starch isolation with a great potential for sorghum in livestock and animal feeds are considered in this work.Keywords: Sorghum, Starch extraction, By-products, Starch digestion, Animal fee