Pseudo stir bar sorptive microextraction fiber using nanoparticles reinforcedsol–gel for the determination of Co(II) and Cd(II) ions in wastewaters

In this work a newly semi polar extraction phase of carboxylated multiwalled carbon nanotube (MWCNTs) reinforced sol-gel immobilized polypropylene hollow fiber was prepared by low temperature hydrothermal process. It is coupled with flame atomic absorption spectroscopy was employed in the extraction and determination of cobalt and cadmium ions in wastewaters. The main factors influencing the pre-concentration and extraction of the metal ions have been examined in detail. Detection limits obtained in this way for Co(II) and Cd(II) ions were 0.0186 and 0.024 ng mL^?1, respectively.     

Computational Fluid Dynamics versus Experiment: An Investigation on Liquid Weeping of Nye Trays

The weeping phenomenon was investigated using some experimental tests and a numerical model. The tests were performed within a 1.22‐m‐diameter pilot‐scale column including two chimney trays and two Nye test trays with an air‐water system. The rates of weeping were measured in the Nye trays with two heights of the weir and a hole area of 5 %. Moreover, the weeping rates in the outlet and inlet halves of the Nye tray and the total weeping rate were calculated. In the next step, an Eulerian‐Eulerian computational fluid dynamics (CFD) technique was used. The results show good agreement between the attained CFD findings and the experimental data.     

Synthesizing and Characterizing of Gelatin-Chitosan-Bioactive Glass (58s) Scaffolds for Bone Tissue Engineering

Nowadays repairing and regenerating of lost or damaged tissue still remain an important challenge in clinical techniques. Due to the variety of available bone grafts, different types of biodegradable materials are being utilized as a scaffold implant. The basic structure of the bone is an excellent natural composite which contains varieties of polymers and ceramics; therefore, it is important to manufacture a bone scaffold featuring sufficient mechanical strength, a good degree of biocompatibility, biodegradation and an increased rate of formation of new tissue. Bioactive glass has an appealing characteristic which can be utilized for repairing purposes as well as to cause a rapid response from the bone graft. In this study, a composite scaffold based on polymer matrix (gelatin-chitosan) and bioactive glass 58s was synthesized in the laboratory. Five samples of polymer scaffold with different proportions of bioactive glass were designed and investigated. The scaffolds were dried with freeze dryer, and a spongy structure was generated. The composite survey was carried out through FTIR technique to examine the crystallization of the structure, XRD to examine the morphology of the porosities, and SEM to examine the size of porosities and formation of apatite. This study reveals that the size of porosities is about 170–320 μm, which is suitable for angiogenesis and cell growth in the bone. The combination of enhanced properties and the formation of apatite on the surface of the scaffolds make them an ideal option as a bone substitute.     

Probiotic yoghurt functionalised with microalgae and Zedo gum: chemical,microbiological, rheological and sensory characteristics

In this study, using a central composite design, the effects of addition of Spirulina platensis and Zedo gum to plain and probiotic yoghurt samples were investigated during storage. Lactobacillus paracasei proliferation was directly dependent on the addition of microalgae and was inversely affected by storage time. Probiotic samples containing S. platensis showed the highest antioxidative activity. Maximum stability was obtained at higher amounts of Zedo gum, while organoleptic and rheological attributes improved at 0.25% Zedo gum. Given the importance of probiotic viability, supplementation of probiotic yoghurt with Zedo gum/S. platensis may be consideredas a novel nutraceutical formulation.     

Investigating shrinkage and moisture diffusivity of melon seed in a microwave assisted thin layer fluidized bed dryer

This work aimed to investigate the drying behavior of melon seed during combined fluidized bed-microwave drying system. Three drying air temperatures (40, 55 and 70 °C), three microwave powers (270, 450 and 630 W) and three air velocities (0.8, 1.5 and 2.3 m/s) were tested. Five mathematical models were selected to fit the experimental data for drying kinetics, and the results revealed that the Aghbashloo et al. model exhibited, in all cases, the best performance in fitting the experimental data (R² varying from 0.99088 to 0.99998; χ² from 0.00000 to 0.00185 and RMSE from 0.02289 to 0.82316). Calculated values of moisture diffusivity for dried melon seed varied from a minimum of 6.51 × 10?10 to a maximum of 6.59 × 10?9 m²/s under the tested drying conditions. Moisture diffusivity values increased as air temperature and microwave power was increased. Shrinkage values were calculated and found to vary in the range from 46.99 to 15.09 %.     

Hyperketonemia during lipopolysaccharide-induced mastitis affects systemic and local intramammary metabolism in dairy cows

Hyperketonemia interferes with the metabolic regulation in dairy cows. It is assumed that metabolic and endocrine changes during hyperketonemia also affect metabolic adaptations during inflammatory processes. We therefore studied systemic and local intramammary effects of elevated plasma β-hydroxybutyrate (BHBA) before and during the response to an intramammary lipopolysaccharide (LPS) challenge. Thirteen dairy cows received intravenously either a Na-dl-β-OH-butyrate infusion (n = 5) to achieve a constant plasma BHBA concentration (1.7 ± 0.1 mmol/L), with adjustments of the infusion rates made based on immediate measurements of plasma BHBA every 15 min, or an infusion with a 0.9% NaCl solution (control; n = 8) for 56 h. Infusions started at 0900 h on d 1 and continued until 1700 h 2 d later. Two udder quarters were challenged with 200 μg of Escherichia coli LPS and 2 udder quarters were treated with 0.9% saline solution as control quarters at 48 h after the start of infusion. Blood samples were taken at 1 wk and 2 h before the start of infusions as reference samples and hourly during the infusion. Mammary gland biopsies were taken 1 wk before, and 48 and 56 h (8 h after LPS challenge) after the start of infusions. The mRNA abundance of key factors related to BHBA and fatty acid metabolism, and glucose transporters was determined in mammary tissue biopsies. Blood samples were analyzed for plasma glucose, BHBA, nonesterified fatty acid, urea, insulin, glucagon, and cortisol concentrations. Differences were not different for effects of BHBA infusion on the mRNA abundance of any of the measured target genes in the mammary gland before LPS challenge. Intramammary LPS challenge increased plasma glucose, cortisol, glucagon, and insulin concentrations in both groups but increases in plasma glucose and glucagon concentration were less pronounced in the Na-dl-β-OH-butyrate infusion group than in controls. In response to LPS challenge, plasma BHBA concentration decreased in controls and decreased also slightly in the BHBA-infused animals because the BHBA concentration could not be fully maintained despite a rapid increase in BHBA infusion rate. The change in mRNA abundance of citrate synthase in LPS quarters was significant between the 2 treatment groups. The results indicate that elevated circulating BHBA concentration inhibits gluconeogenesis before and during immune response to LPS challenge, likely because BHBA can replace glucose as an energy source.