Effect of sevelamer on aortic pulse wave velocity in patients on hemodialysis: a prospective observational study

Aortic stiffening and aortic calcification are risk factors for cardiovascular events in hemodialysis (HD) patients, and these 2 risk factors are interrelated. Sevelamer decreases aortic calcification but its effect on aortic stiffness has not been investigated previously. Thirteen HD patients commencing sevelamer treatment and 13 matched controls were followed for 11 months. Aortic pulse wave velocity (PWV), augmentation index (AIx), and levels of inhibitors of vascular calcification (fetuin-A, matrix-GLA-protein, osteoprotegerin/RANKL) were measured at baseline and at the end of follow-up, and the differences between the groups were compared. Determinants of the changes in PWV during follow-up were assessed by multivariate linear regression. At baseline, PWV was 9.93 (2.10) m/s in sevelamer-treated patients and 9.20 (2.84) m/s in control patients (p=0.464). By the end of follow-up, PWV decreased by 0.83 (2.3) m/s in sevelamer-treated patients while it increased by 0.93 (1.88) m/s in controls (p=0.042). The direction of changes in AIx were similar, but not statistically significant. There were no significant differences in the levels of inhibitors of calcification either at baseline or during follow-up. In multivariate linear regression sevelamer treatment, diabetes, heart rate, and C-reactive protein were related to the change in PWV. These data suggest that sevelamer treatment is associated with an improvement in aortic stiffness in HD patients, but it does not seem to affect serum levels of inhibitors of vascular calcification.     

Effect of water and crude oil on mechanical and thermal properties of epoxy‐clay nanocomposites

Epoxy‐clay nanocomposites were synthesized by high shear mixing (HSM) technique using diglycidyl ether of bisphenol A (DGEBA) epoxy reinforced by Nanomer I.30E nanoclay. Disordered intercalated with some exfoliated structure were found in the resultant nanocomposites. The fabricated samples were exposed to water and crude oil to investigate the effect of nanoclay addition on diffusivity and amount of liquid uptake. The results showed good improvement in the barrier properties of epoxy as a result of clay addition. The average reduction in diffusivity and maximum water uptake for nanocomposites containing 1% nanoclay were 51% and 8%, respectively. The maximum water uptake was about double the maximum oil ingress for both neat epoxy and nanocomposites. Obvious degradations in thermal and mechanical properties of neat epoxy and nanocomposites were observed as a result of liquid uptake; with less severe impact on nanocomposites. The reduction in glass transition temperature was about 8% for each 1% of water uptake for nanocomposites as compared to 15% for neat epoxy. The tensile strength and the elastic modulus of neat epoxy and nanocomposites were adversely affected by water and oil uptake while the fracture strain was slightly improved; a behavior found to be proportional to the amount of liquid uptake. The diffusion mechanism of water in neat epoxy was well predicted by Fickian model, while that of the nanocomposites was better fitted with Langmuir model. POLYM. COMPOS., 35:318–326, 2014. © 2013 Society of Plastics Engineers     

Combined PIXE/PIGE and IBIL with external beam applied to the analysis of Merovingian glass beads

New improvements on our archaeometry line at the cyclotron of the Institute of Nuclear and Atomic Physics and of Spectrometry of the University of Liège have allowed the use of PIXE/PIGE and IBIL in-air for the analysis of cultural heritage objects. The extraction is performed through a 100 nm thick Si₃N₄ window. The detection set-up consists now of two X-ray and one γ-ray detectors, together with a fiber optic UV–visible spectrometer. This set-up has already been tested for the analysis of modern corundum [1] and is now adapted to the analysis of archaeological artefacts. In this work, we have used it to analyse 216 out of the 5000 Merovingian glass beads that come from the necropolis of Bossut-Gottechain (Belgium), one of the most important ever found in Belgium.The IBA analyses confirmed the typological division of different beads groups through chemical composition that gives us new insights on fabrication techniques of glass matrices and colorants.     

Extraction of Coriander Oil Using Twin‐Screw Extrusion: Feasibility Study and Potential Press Cake Applications

This study presents an assessment of the vegetable oil extraction from coriander fruits through mechanical pressing, more specifically twin‐screw extrusion. This comprises an evaluation of the oil recovery obtained and its respective quality, as well as the specific mechanical energy, representing an economical point of view. With regard to the extrusion optimization, the screw configuration, the device's filling coefficient and the pressing temperature were varied. The screw configuration was shown to exhibit a key influence on the extraction efficiency and oil recoveries of at least 40 % were reached when the pressing zone was positioned immediately after the filter and consisted of 50 mm long, reverse screws with a ‐33 mm pitch. Furthermore, with a device's filling coefficient of 39.4 g/h rpm and a pressing temperature of 120 °C, an oil recovery of 47 %, the highest of this study, was reached with concurrent low energy consumption. Next to this, operating parameters of 47.1 g/h rpm and 80 °C resulted in the production of a press cake with the lowest residual oil content (15 %) in this study, although this also involved a significant increase in the filtrate's foot content. All the produced oils were of acceptable quality (<1.5 % acidity), showed high petroselinic acid content (73 %), and were pleasantly scented.     

Premature Failure of an Industrial Mixer Timing Gears

A systematic and practical methodology was adopted to determine the root cause(s) of the premature failure of a pelletizer mixer timing gear. The investigation activities covered all possible causes of failure and included field examination, interview of engineers and operators, lubrication analysis, metallurgical examination. Fracture surfaces and microstructure of gear material were examined, and hardness profiles were developed. Analyses of shaft misalignment and teeth profiles were performed and found to be within acceptable limits. Results clearly indicate the surface hardness deficiencies in many locations specifically at center of the driven gear, area of severe pitting. The developed hardness profile for all locations is lower than that specified by the manufacturer. Fractographic analysis revealed that failure occurred by pitting followed by crack propagation. A number of cracks are seen to branch in different directions indicating the presence of high contact stresses combined with weak surface strength. Bending fatigue and pitting fatigue stress calculations revealed that the safety factor under contact is well below the desired value.     

Accuracy of simplified sampling procedures for estimating milk composition in dairy ewes

Simplified designs of milk-composition recording, based on information from a single monthly milking, adjusted or not for interval between milkings and for milk yield, were simulated and evaluated for 2553 ewe-test-day records belonging to 155 lactations of Churra dairy ewes. Accuracy of simplified methods was evaluated by comparing estimated trait values (fat, protein, casein and total solid yields) with those observed both in a reference plan, where the two daily milkings were recorded at weekly intervals (A1), and in the official A4 milk recording (monthly records of the two daily milkings). Trait yields per lactation were estimated and adjusted to the only milking period (days in milk 30-120). Estimates of milk component traits were less precise when monthly designs, including the A4 design, were compared with a weekly sampling of both a.m. and p.m. milkings, with fat yield being the most difficult trait to estimate. All options with one daily milking every month were more accurate when the corresponding plan was based on, or began with, the a.m. milking. Adjustment for the preceding interval between milkings or milk yield did not improve sampling accuracy. The design alternating a.m. and p.m. milkings every month, without adjustment, is suggested for recoding milk component traits in dairy ewes.     

Cyber Security Intrusion Detection for Agriculture 4.0: Machine Learning-Based Solutions,Datasets, and Future Directions

In this paper, we review and analyze intrusion detection systems for Agriculture 4.0 cyber security. Specifically, we present cyber security threats and evaluation metrics used in the performance evaluation of an intrusion detection system for Agriculture 4.0. Then, we evaluate intrusion detection systems according to emerging technologies, including, Cloud computing, Fog/Edge computing, Network virtualization, Autonomous tractors, Drones, Internet of Things, Industrial agriculture, and Smart Grids. Based on the machine learning technique used, we provide a comprehensive classification of intrusion detection systems in each emerging technology. Furthermore, we present public datasets, and the implementation frameworks applied in the performance evaluation of intrusion detection systems for Agriculture 4.0. Finally, we outline challenges and future research directions in cyber security intrusion detection for Agriculture 4.0.