Physicochemical,Rheological, and Thermal Properties of Six Types of Honey from Various Floral Origins in Tunisia

The present study was undertaken to determine the physicochemical, rheological, and thermal properties of six types of Tunisian honey samples from various floral origins (eucalyptus, orange, thyme, mint, rosemary, and horehound). All the honey samples exhibited non-Newtonian behavior at a shear rate ranging between 0.01 and 500 s^–1, with the highest levels of viscosity (µ) being observed for thyme, followed by eucalyptus, rosemary, mint, orange, and horehound honeys, respectively. The effect of temperature on the dynamic viscosity of the samples followed an Arrhenius-like pattern, with activation energy values ranging from 21.23 to 34.91 kJ/mol. The results from oscillatory rheology analysis also revealed that the loss modulus predominated over the storage one in the whole frequency range. As determined by differential scanning calorimetry, the glass transition (T_g) and melting temperatures of the Tunisian honey samples varied between –41.55 and –47.06 °C and between 197.9 and 221.1°C depending on their sugar compositions, respectively.     

A fully personalization strategy of E-learning scenarios

The personalization in E-learning systems has been the subject of many recent research efforts. While a large number of systems have been implemented, many of these systems allow the application of very few if not just one predefined personalization strategy. This is a constraint for providing effective E-learning experience and for rationalizing the personalization needs of the pedagogues, the professors and the learners. In this paper, we propose a new approach for personalization of learning scenarios based on two levels: The first level allows the personalization of learning scenarios according to a predefined personalization strategy. The second level allows teachers to select personalization parameters and combine them flexibly to define different personalization strategies according to the specifics of courses. The proposed solution is a step to federate the research efforts on the E-learning personalization by integrating and combining the personalization parameters. Concerning the technological aspect, Web service technology constitutes an operational solution for implementing our approach and for the interoperability with other E-learning personalization systems. Beside the implementation of an interoperable solution, we also aim to enable teachers to provide proper personalized learning scenarios.     

Serum Oxidized-LDL is Associated with Diabetes Duration Independent of Maintaining Optimized Levels of LDL-Cholesterol

Oxidized low-density lipoprotein (ox-LDL) plays a key role in the progression of atherosclerosis and diabetes complications. The aim of this study was first, to evaluate the association between ox-LDL and diabetes duration, and second, to examine serum level of ox-LDL in patients with prolonged diabetes and a desirable LDL-cholesterol level. A total of 36 type-2 diabetic patients with a diabetes duration of more than 5 years, 36 newly diagnosed diabetic patients, and 36 age-, sex- and BMI-matched healthy participants were recruited. Healthy participants and newly diagnosed patients were not receiving any treatment. All patients with prolonged diabetes had desirable LDL-cholesterol levels (<100 mg/dL), according to the adult treatment panel-III guidelines. While LDL-cholesterol was significantly lower in patients with diabetes duration >5 years, in comparison to newly diagnosed patients (P < 0.01), ox-LDL was significantly higher in patients with prolonged diabetes (P < 0.001). The ox-LDL-to-LDL ratio was dramatically higher in patients with diabetes duration >5 years in comparison to newly diagnosed patients and healthy participants (P < 0.001). Ox-LDL was significantly associated with diabetes duration (r = 0.519, P = 0.001). In multivariate analysis, this association remained significant (β = 0.501, P = 0.003) after adjustment for potential confounders. In conclusion, this study showed that the serum ox-LDL level increases with the length of diabetes, even though the patients’ LDL-cholesterol level is maintained at a desirable level. Our findings highlight that possibly more attention should be focused on markers of oxidative stress in the management of lipids in diabetic patients.     

The Use of Thermal Lattice Boltzmann Numerical Scheme for Particle-Laden Channel Flow with a Cavity

In this article, particle-laden flow in a channel with heated cavity has been investigated. Calculations were performed using a point force scheme for particle dynamics, while the process of fluid renewal was modeled using the double-population thermal lattice Boltzmann method. Point-particle formulation accounts for the finite-size dispersed phase and the forces acting on the particles were modeled through drag force correlations. Two-way interactions of solid-fluid calculation were considered by adding an external force term for feedback that forced particles in the evolution of fluid distribution function. The method was first validated with steady state flow in a channel with cavity in the presence and absence of a heat source. It was then applied to mixed convection flow laden with particles at various Grashof numbers. The particle dispersion characteristics were examined in detail, where the particle removal rate from cavity upon cavity aspect ratio was emphasized. The effect of the Reynolds number on particle distribution was further investigated numerically by varying the speed of inlet flow into the channel.     

Evaluation of a wearable computer system for telemonitoring in a critical environment

This paper reports on the evaluation of a wearable computer system designed for use in a critical environment, namely the intensive care unit of a hospital. The nature of the application raised ethical issues for testing in a clinical environment and standard evaluation techniques could not easily be applied. The system was therefore evaluated by clinicians in a multi-tasking environment with a simulated set of patient scenarios. Measures of suitability and wearability were applied. The results were encouraging and the system was deemed suitable for further evaluation in the clinical setting, subject to ethical approval.     

Comparison of risk factors for contrast‐induced acute kidney injury between patients with and without diabetes

Although it is well known that diabetics are at a higher risk of contrast‐induced acute kidney injury (CI‐AKI) than nondiabetic patients, the reason for this discrepancy is not well known. Thus, in this study, we compared the predisposing factors for CI‐AKI between patients with and without diabetes. We prospectively studied 290 consecutive in‐hospital patients including 88 diabetics undergoing coronary angiography or a percutaneous coronary intervention in Kowsar hospital, and we compared risk factors for CI‐AKI between diabetic and nondiabetic patients. CI‐AKI was defined as RIFLE criteria within 48 hours after contrast exposure. The incidence of CR‐AKI was significantly higher in diabetic patients compared with nondiabetics (P<0.05). The incidence of CI‐AKI was significantly higher in patients with diabetes and left‐ventricular ejection fraction ≤40%, hypercholesterolemia, serum creatinine ≥1.1 mg/dL, estimated glomerular filtration rate (eGFR) <90 mL/min, Contrast volume ≥80 (mL), maximum safe contrast volume factor of 1.5, and dehydration, while in nondiabetics, a significantly higher incidence of CR‐AKI was observed in those with serum creatinine ≥1.1 mg/dL (P=0.02) and/or eGFR<60 mL/min (P=0.01). Multiple logistic regression analysis showed hyperchlosteremia to be the strongest predictor of AKI (P=0.01, B:14.5) in diabetics, followed by eGFR<90 (P=0.05, B:12.4) but, in nondiabetics, only eGFR<60 predicted the occurrence of CI‐AKI (P=0.04, B:2.3). It seems that the predisposing factors to CI‐AKI differ in diabetics and nondiabetics. In patients with diabetes, hypercholesterolemia is the strongest predictor of CI‐AKI, followed by eGFR and diabetics are at risk for CI‐AKI in the early stage of chronic kidney disease (stage 2), accounting for the higher incidence of CI‐AKI in them.     

Stress analysis of 3-dimensional IC package as function of structural design parameters

Solid Liquid Inter-Diffusion (SLID) is a technology that has recently been utilized to fabricate 3D ICs. Since application of this technology is in its infancy stages, manufacturability and reliability of these bonds are still under heavy investigations. This study presents an elastic-plastic finite element and analytical analyses that were implemented to evaluate effect of package design parameters on thermo-mechanical reliability of the SLID bonds and copper interconnects. A numerical experiment is designed in which several design parameters; die thickness, bond size, underfill stiffness and substrate thickness, are varied in 3 levels. Stress in SLID bonds and in copper interconnects were evaluated using the 3-dimensional finite element analysis as well as an analytical approach. The results show that die and substrate thicknesses are the most influential factors among the selected parameters on stress at the interface and on copper interconnects. Main effect results for stress analysis in SLID bonds using finite element shows that die thickness and underfill stiffness are the most influential factors in defining stress at SLID bonds. Results of the analytical approach confirm the finite element analysis. It is shown that effect of interconnect size and pitch is very small compared to die thickness. In average increasing die thickness increases both shear and peeling stresses at the interfaces and copper interconnects.     

Salmonella contamination of laying-hen flocks in two regions of Algeria

A preliminary epidemiological study of Salmonella contamination in laying-hen flocks was carried out in the regions of Annaba and Eltarf, Algeria, from March to October 2008 and March to November 2009. Our objectives were (i) to estimate the prevalence of infection by Salmonella spp. in seven pooled samples during the hens' laying period (ii) to identify the serotypes and antimicrobial resistance phenotypes of isolates, and (iii) to characterize the factors that may be related to Salmonella contamination in Algerian henhouses. For this purpose, 18 out of 22 operational laying-hen houses were sampled one to three times during these periods: once at the start of laying (pullets aged 22–31 weeks), once in the middle of laying (47–60 week) and once at the end of laying prior to depopulation (70–86 week). The flocks'Salmonella status was assessed by collecting 2754 environmental samples that were analyzed according to the ISO 6579 method. The antibiotic resistance of Salmonella strains was tested as per the guidelines of the Clinical and Laboratory Standards Institute (CLSI). The relationship between each potential risk factor and the Salmonella status of laying-hen flocks was evaluated by calculating the relative risk with 95% confidence intervals. Eight flocks tested positive for Salmonella spp., with a higher prevalence at the end of laying than at either the beginning or middle. Only 19 isolates were recovered from the 2754 samples analyzed and nine different serotypes identified. S. enteritidis (n = 4) was the most prevalent serovar, along with S. Kentucky and S. Hadar (n = 3), followed by S. Heidelberg, S. Manhattan and S. Virchow (n = 2), whereas S. Dublin, S. Typhimurium and S. Albany were found only once. Thirteen isolates were resistant to at least one antimicrobial agent. Of these, six were resistant to at least three different antimicrobial classes. Salmonella serovar Kentucky isolates were resistant to fluoroquinolones with ciprofloxacin MIC ≥ 8 mg/L. Six risk indicators were identified as potentially related to the Salmonella status of layer houses.     

Mechanical and Flammability Properties of ATH‐Filled EPDM Compositions

Poly(ethylene‐co‐propylene‐co‐diene) (EPDM) compositions filled with mixtures of aluminium hydroxide (ATH) and carbon black (HAF) were evaluated for electrical applications. Mechanical and flammability tests were carried out in order to find out the relative amounts of the two fillers which would give the best balance of properties, mainly to meet the Brazilian Society for Technical Standards‐ABNT. For good flame resistance, amounts as high as 160 phr ATH, at least, must be used.