A model for learning objects adaptation in light of mobile and context-aware computing

The growth usage of mobile technologies and devices such as smartphones and tablets, and the almost ubiquitous wireless communication set the stage for the development of novel kinds of applications. One possibility is exploiting this scenario in the field of education, so creating more intelligent, flexible and customizable systems. Mobile devices can be used to help students to learn, considering their learning styles, surroundings, devices and profiles. In this way, the main goal of this article is to propose EduAdapt, an architectural model for the adaptation of learning objects considering device characteristics, learning style and other student’s context information. To make this adaptation we used inferences and rules in a proposed ontology, named OntoAdapt. We believe that such ontology can help recommending learning objects to students or adapt these objects according to the context (context-aware computing). We evaluate this proposal in two ways. Firstly, we used scenarios and metrics to assess the ontology. Secondly, we developed a prototype of EduAdapt model and submitted to a class of 20 students with the intention of evaluating the usability and adherence to adapted objects, resulting in a 78 % of acceptance. In brief, the evaluation presented encouraging results, indicating that the proposed model would be useful in the learning process.     

Microencapsulation of Rosemary Essential Oil: Characterization of Particles

This study evaluated the influence of wall material concentration (10–30%), inlet temperature (135–195°C), and feed rate (0.5–1.0 L · h^?1) on the properties of rosemary oil microencapsulated by spray-drying, with gum arabic as carrier. Powder recovery, surface oil, oil retention, and hygroscopicity varied from 17.25%–33.96%, 0.03%–0.15%, 7.15%–47.57%, and 15.87%–18.90%, respectively. The optimized conditions were determined to be a wall material concentration of 19.3%, an inlet air temperature of 171°C, and a feed flow rate of 0.92 L · h^?1. At this condition, particles presented no fissures and the compositions of pure and microencapsulated oil were similar. The sorption isotherms could be described by the GAB model.     

Effects of plasticizers on the properties of oat starch films

Oat starch films were prepared by casting using glycerol, sorbitol, glycerol–sorbitol mixture, urea and sucrose as plasticizers. The effects of these plasticizers on the microstructure, moisture sorption, water vapor permeability (WVP) and mechanical properties were investigated using films stored under a range of relative humidities. The plasticizer type did not affect significantly (p ≤ 0.05) the equilibrium moisture content of films, except at 90% relative humidity (RH). Films without plasticizer adsorbed less water and showed higher WVP than plasticized ones, indicating the antiplasticizing effect observed in this work. In general, a decrease in stress at break and Young's modulus and an increase in strain at break were observed when RH increased in all film formulations. Films without plasticizer showed higher stress at break values than the plasticized ones and presented stable strain at break under a range of RH. Sucrose films were the most fragile at low RH while glycerol films were the most hygroscopic.     

Reactivation of ulcerative rectocolitis with the use of non-steroidal anti-inflammatory drugs. Report of a case and review of the literature

The case of a patient with ulcerative colitis and isolated sacro-ileitis is presented. She suffered reactivation of the intestinal disease with diclofenac. The patient was allergic to sulfasalazine and was using fish oil fatty acid. The possible mechanisms of reactivation of the inflammatory bowel disease with non-steroidal anti-inflammatory drugs are discussed. It is suggested when necessary the utilization of non-steroidal anti-inflammatory drugs that inhibits the lipoxygenase in these patients.     

An intelligent system for prognosis of noncommunicable diseases’ risk factors

Noncommunicable diseases are the main reason to the rise of diseases incidence in the developed world. The management and prevention of these diseases can be done by controlling the behavioral and biological risk factors which are related to them. ChronicPrediction is an intelligent system for noncommunicable diseases care which determines in real time the impact on risk factors due to actions taken by users. Based on impact information, the system presents on users’ smartphones strategic messages to help in their treatment. ChronicPrediction applies Bayesian Networks (BNs) which use risk factors for mapping the causes of noncommunicable diseases worsening. The support to multiple chronic diseases and the integrated use of multiple BNs based on risk factors are the main contributions of this work and differentiate the proposed system from related work. We have built a functional prototype that allowed us to conduct two experiments. The first one successfully tested the main functionalities provided by ChronicPrediction to support BNs based on risk factors and the sending of messages to users’ smartphones. The evaluation involved the building of a BN for predicting coronary artery disease made with real world data obtained in a prospective cohort study. The study involved 302 patients from a hospital localized in southern Brazil. The second experiment assessed the ChronicPrediction support to multiple BNs at same time. The test involved the previous BN and another from a thirty part research work to map risk factors of diabetes. The results were encouraging and show potential for implementing ChronicPrediction in real-life situations.     

Hydrogels of starch/carboxymethyl cellulose crosslinked with sodium trimetaphosphate via reactive extrusion

Hydrogels are materials with advantages in specific applications, such as, retention of food active compounds. This work aims to develop starch (S)/carboxymethyl cellulose (CMC) hydrogels with porous structure, using reactive extrusion to promote crosslinking with sodium trimetaphosphate (STMP). The expansion, porosity, degree of substitution, gel fraction, swelling properties, and FTIR are studied, comparing S, S/CMC, S/STMP, and S/CMC/STMP formulations. Samples containing STMP present the same degree of substitution (0.050 ± 0.001). Higher porosity and percentage of open pores are observed in the mixed hydrogel (S/CMC/STMP). Crosslinking increase the swelling capacity at pH 7, and this property, just like the gel fraction, are sensitive to pH variations. The hydrogel S/CMC present the highest swelling rate compared with the other samples, suggesting strong interaction between components. The reactive extrusion process is efficient to produce starch and starch/CMC hydrogels crosslinked with STMP and the overall results demonstrate the advantages of the mixed hydrogel.