Preparation and monitoring of small animals in renal MRI

Renal diseases remain devastating illnesses with unacceptably high rates of mortality and morbidity worldwide. Animal models are essential tools to better understand the pathomechanism of kidney-related illnesses and to develop new, successful therapeutic strategies. Magnetic resonance imaging (MRI) has been actively explored in the last decades for assessing renal function, perfusion, tissue oxygenation as well as the degree of fibrosis and inflammation. This chapter aims to provide an overview of the preparation and monitoring of small animals before, during, and after surgical interventions or MR imaging. Standardization of experimental settings such as body temperature or hydration of animals and minimizing pain and distress are essential for diminishing nonexperimental variables as well as for conducting ethical research.This publication is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers

A New Phase Measurement Technique for RF Power Amplifier Only Measuring Magnitudes

In this study, a new phase measurement setup to measure magnitudes and phases of the fundamental components and intermodulation created by an amplifier under two tone excitation is reported. There are three signal generators, one digital attenuator and one spectrum analyzer in the measurement setup. There is no need to any other special electronic circuits (e.g., mixer, filter, etc.). Phase is found/measured mathematically based on magnitude measurements. Also absolute phase difference between the frequency components can be measured. Measured phase error is better than 1 degrees for repetitive measurements

Behavioral Modeling of Asymmetric Intermodulation Distortion of Nonlinear Amplifier

In this study, a behavioural modelling is proposed to model asymmetric IMD components produced in the two tone excitation of nonlinear amplifiers. Model parameters are extracted based on single tone and two-tone measurement results. Then measurement results and model predictions are compared for a four-tone signal

Comparison of ozonation and coagulation decolorization methods in real textile wastewater

Several treatment approaches such as ozonation, metal coagulation, (ferric chloride and alum), polymer treatment (Polyethylene polyamine, PP, and Cyanoguanidine Polymer, CP) and their combinations for decolarization of biologically treated textile wastewater (BTTWW) were applied. Wastewater samples were taken from effluent stream of an activated sludge treatment system in a synthetic-cotton textile factory. Absorbance, color, chemical oxygen demand (COD) measurements were done to determine optimum conditions. At coagulation experiments, neither ferric chloridenoralum decreased the color parameter below the discharge standard. Ozonation was found to be efficient in removing color from BTTWW as color degradation reached steady-state after 10 min. However color standard was met at higher ozone dosages (20 min). Polymer coagulation (200 mg/L) was found to be practical in removing color from BTTWW. Ozonation prior to polymer coagulation (pre-ozonation) not only improved the color removal efficiency but also decreased the required polymer dosage by 75%. Operational costs of ozonation, PP and pre-ozonation-subsequently PP were found to be 0.37 (sic)/m(3), 0.50 (sic)/m(3), and 0.26 (sic)/m(3), respectively

Evaluation of hydrogen production via electrolysis with ion exchange membranes

In this study, the ion exchange membranes are proposed and tested in an electrolysis process for hydrogen production from acidic and alkaline solutions. The results of the experiments are then compared to evaluate the effect of ion exchange membranes on the performance of the electrolysis process. This study shows that the ion exchange membranes can improve the performance of the electrolysis reactor and supply high pH differences between compartments due to the membrane's feature of low electrical resistance and high resistance to pH changes. All anion exchange membrane, cation exchange membrane, and bipolar membrane are used individually as a separator between anode and cathode chamber of electrolysis reactor to evaluate the effect of these ion exchange membranes on system efficiency. Also, the comparison of using ion-exchange membranes to generate hydrogen in the acidic-alkaline electrolysis reactor is studied for the first time in this study. The electrolysis reactor is tested using various electrochemical techniques and analyzed thermodynamically. The maximum hydrogen production rate is determined with the bipolar membrane as 11.4 mmol/h, while the highest energy and exergy efficiencies are found for the reactor configuration with anion exchange membrane as 82% and 68%, respectively. (C) 2019 Elsevier Ltd. All rights reserved

Experimental investigation and analysis of a new photoelectrochemical reactor for hydrogen production

In this research paper, an experimental investigation of photoactive material titanium dioxide (TiO2) coated on 180 cm(2) 316 stainless steel anode is undertaken to study the photoresponse on photoelectrochemical (PEG) hydrogen production. The TiO2 nanoparticles are first prepared via sol-gel method. A large surface 316 stainless steel anode is coated with TiO2 nanoparticles by a dip coating apparatus at a withdraw rate of 2.5 mm/s. The nanoparticles are carried on the stainless steel substrate by two-step annealing procedure. The potentiostatic studies confirm the photoactivity of TiO2 nanoparticles in a photoelectrochemical reactor when exposed to solar ultraviolet (UV) light. The photon to current efficiency measurements carried out on the PEC reactor with TiO2 coated large surface stainless steel as photoanode demonstrate a significant increase of photoresponse in UV light compared to the uncoated stainless steel prepared under similar conditions. Upon illumination at a power density of 600 W/m(2) , the hydrogen production is observed in TiO2 coated stainless steel substrate at a measured rate of 51 ml/h while no illumination conditions show a production rate of 42 ml/h. In comparative assessments, the TiO2 coated substrate shows an increase in photocurrent of 10 mA with an energy efficiency of 1.32% and exergy efficiency of 3.42% at an applied potential of 1.6 V. The present results show a great potential for titanium nanoparticles semiconductor metal oxide in photoelectrochemical hydrogen production application. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved

Treatment of idiopathic macular hole with silicone oil tamponade

Biljana Ivanovska-Adjievska,1 Salih Boskurt,1 Faruk Semiz,1 Hakan Yuzer,1 Vesna Dimovska-Jordanova21European Eye Hospital, Skopje, Macedonia, 2Clinic for Eye Diseases, University "St Cyril and Methodius", Skopje, MacedoniaPurpose: We analyzed the anatomical and visual outcomes after surgical treatment of idiopathic macular holes with pars plana vitrectomy, internal limiting membrane (ILM) peeling using Brilliant Blue dye, and silicone oil tamponade without postoperative posturing.Methods: This was a retrospective interventional study of 10 eyes in eight patients who underwent surgical treatment of idiopathic macular holes using pars plana vitrectomy, ILM peeling using Brilliant Blue dye, and silicone oil tamponade without postoperative posturing. The preoperative staging of macular holes and postoperative anatomic outcomes were assessed using spectral-domain optical coherence tomography.Results: All patients were women with a mean age of 66.86 ± 4.8 years. In two patients, bilateral macular holes were present and both eyes were operated on. Stage 2 macular hole was diagnosed in three eyes, three eyes had stage 3, and four eyes had stage 4 macular holes. Anatomical success and closure of the macular hole was achieved in nine eyes (90%) after one operation. In one eye, the macular hole was closed after reoperation. The preoperative mean best-corrected visual acuity (BCVA) was 0.15 decimal units (0.8 logMAR units). Until the end of the follow-up period, BCVA was 0.25 decimal units (0.6 logMAR units). Visual acuity was improved in seven patients (70%). In two patients (20%), visual acuity remained at the same level, and in one eye (10%), visual acuity decreased. Postoperatively, all patients reported a significant reduction of metamorphopsia.Conclusion: Initial results after 20G pars plana vitrectomy with peeling of the ILM, use of dye (Brilliant Blue), and tamponade with silicone oil without postoperative posturing gave good anatomical and functional outcome in terms of visual acuity and reduction of metamorphopsia. Taking into account the age of the patients, this method, which does not require prolonged postoperative face-down posturing, was well tolerated by the patients. Because the anatomical and visual outcome as well as the rate of postoperative complications are comparable to those when gas is used as a tamponading agent, silicone oil tamponade can also be safely used as a first option in surgery of macular holes. However, a longer period of follow-up of the operated eyes, as well as a larger group of operated eyes, will be required to identify long-term outcomes of this surgical treatment.Keywords: macular hole, silicone oil, ILM peeling, pars plana vitrectom

Functionalization of cotton fabric with nanosized TiO2 coating for self-cleaning and antibacterial property enhancement

In this study, titanium dioxide (TiO2) was used as coating compound to add self-cleaning and antibacterial functionality properties to the cotton fabric. TiO2-consisting coating compounds were prepared at four different processing temperatures (20, 40, 60, and 80°C) in order to examine the influence of process temperature on average particle size. Among the prepared solutions, the one prepared at 80°C process temperature was selected for the dip coating application of the 100% cotton fabric, which formed a transparent nanosized TiO2 film on the fibrous structure of fabric. Dip coating trials were done at five coating temperatures of 20, 40, 60, 80, and 100°C. TiO2-coated and uncoated fabric samples were then tested to evaluate their self-cleaning and antibacterial activities. A self-cleaning activity test was conducted using uncoated and TiO2-coated fabric samples which were stained with hot tea solution via dipping method. Stained fabric samples were illuminated under a solar simulator for the color changes to measure photocatalytic degradation of stain colors. Antibacterial performance of TiO2-coated and uncoated fabric samples was determined against pure cultures of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213. © 2015, American Coatings Association