Clay/Biopolymer Composite and Electrorheological Properties

The combination of clays with polymers having different characteristics opens a way to new composite materials showing novel properties. Electrorheological (ER) fluids show phase transition from a liquid to a solid-like state between the electrodes of a rheometer due to the interactions of polarized particles. Composite systems comprising biodegradable chitosan (CS) and natural bentonite (BNT) are important in ER applications. In this study, BNT/CS composites were synthesized by the in situ method. The structure and morphology of the synthesized composites were characterized using X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), and scanning electron microscopy (SEM) techniques. Thermal stability was observed to increase with the presence of BNT clay. Conductivity of the composites was found the suitable range for ER measurements. According to ER results, BNT/CS composites were found to be sensitive to external electric field strength, exhibiting a typical shear thinning non-Newtonian viscoelastic behavior

Dual Response of Materials under Electric and Magnetic Fields

The electrorheological (ER) effect is known as the change in the rheological behaviors of ER fluids under applied electric field E. When an E is imposed, ER fluids show phase transition from a liquid to a solid-like state due to the interactions of polarized particles. This solid-like behavior of particles is due to the increasing viscosity of suspensions. ER materials belong to a family of controllable fluids. ER fluids are dispersions of solid particles in a hydrophobic insulating dispersion medium. These solid particles play a very important role in the ER activity of dispersions. As the dispersed phase, diverse materials such as polymer blends, gels, biodegradable materials, clays, graphene oxide, hybrid nanocomposites, copolymers, ionic liquids, and conducting polymers have been proposed. In the magnetorheological fluids, this control is provided with magnetic field. Various magnetic particles such as carbonyl iron and iron oxides have been suggested as MR material. The combined effect of magnetic and electric field produces intensified rheological changes in the suspensions. This synergic effect is termed as electromagnetorheological effect (EMR). The EMR effect provides a new strategy to control the rheological properties of dispersions

Helicobacter pylori Eradication Lowers Serum Asymmetric Dimethylarginine Levels

Introduction. Microbial pathogens, one of them is Helicobacter pylori (H. pylori), have frequently been implicated in the atherogenesis. Endothelium-derived nitric oxide (NO) is synthesized from L-arginine by nitric oxide synthase (NOS) and plays a pivotal role in the regulation of vascular tone. Asymmetric dimethylarginine (ADMA) is the most potent endogenous NOS inhibitor. Elevated levels of ADMA have been reported in many circumstances associated with a high cardiovascular risk. The aim of the present study was to investigate whether the eradication of H. pylori infection affects serum ADMA levels. Materials and Methods. Forty-two H. pylori-positive patients were enrolled in the study. Triple therapy for 14 days were given to all patients. Serum ADMA levels were measured at baseline and 2 months after therapy. Results. Eradication was achieved in 34 (81%) patients. The mean serum ADMA levels before and after therapy were 1, 77 ± 0, 30 and 1, 67 ± 0, 29 ng/mL in the group with H. pylori eradicated and 1, 63 ± 0, 28 and 1, 56 ± 0, 32 ng/mL in the noneradicated, respectively. We detected statistically significant decreased serum ADMA levels after therapy in H. pylori eradicated group. Conclusion. These findings have indicated that eradication of H. pylori infection may decrease the risk of atherosclerosis and cardiovascular events

Determination of biogenic amines in licorice (Glycyrrhiza glabra) by ion-pair extraction and liquid chromatography-tandem mass spectrometry

WOS: 000397419600007PubMed: 27381870BACKGROUND: Ion-pair extraction combined with liquid chromatography-tandem mass spectrometry method has been proposed for the determination of biogenic amines in licorice samples. RESULTS: Limit of detection and limit of quantitation for the biogenic amines were 1.4-2.7 and 4.7-9.1 ng mL(-1), respectively. Relative standard deviations based on five replicate extraction of 100 ng mL(-1) of each biogenic amine were <4.7% for intra-day and 7.4% for inter-day precision. The method described in this study has been shown to be in accordance with satisfactory accuracy and good reproducibility for the quantitative determination of biogenic amines in licorice samples. Nine biogenic amines (putrescine, cadaverine, histamine, spermine, spermidine, tyramine, tryptamine, agmatine and phenylethylamine) were detected in licorice samples and total biogenic amine concentrations were determined at 369 ng mL(-1) in fresh and 3532 ng mL(-1) in non-fresh licorice samples. Putrescine was found at the highest concentrations to be up to 704 ng mL(-1) in all the analyzed samples, followed by tyramine (675 ng mL(-1)) and tryptamine (282 ng mL(-1)). Putrescine, tyramine and spermine concentrations were dramatically increased, whereas agmatine concentration was significantly decreased, in non-fresh licorice samples compared to fresh ones. CONCLUSION: The consumption of freshly prepared licorice is recommended because of the relatively low concentration of total biogenic amines. (C) 2016 Society of Chemical IndustryBulent Ecevit UniversityBulent Ecevit UniversityThe authors wish to thank Bulent Ecevit University for the opportunity and support to carry out this research. The authors also thank the Editing Office of Bulent Ecevit University for linguistic corrections

Employing remote sensing technique to monitor the influence of newly established universities in creating an urban development process on the respective cities

Universities have a wide range of effects on the development of the cities, economic growth and socio-cultural structures of the communities. Accordingly, the Turkish government has encouraged the establishment of the higher education institutions to support the regional development especially in the underdeveloped areas. In this study, 13 universities established after 2006 in the eastern and south-eastern regions of the country were analysed for the determination of the effects of the university establishments in the land use patterns. To fulfil this aim NDVI differencing technique covering a period of 10–13 years was performed within the 1 km, 3 km and 5 km buffer rings around the campuses as well as the city centres. The city centres of three additional universities from the same region with older establishment periods varying between 1950 and 1980 were also analysed to compare the results. The results showed that the average of the negative changes in the city centre boundaries was 4.49%, and 6 of the 13 universities conduced to urban development, whereas the remaining 7 ones did not create a significant urban development

Caffeic acid phenethyl ester and vitamin E moderates IL-1 beta and IL-6 in bleomycin-induced pulmonary fibrosis in rats

WOS: 000246930700014The aim of this study was to investigate the effects of Caffeic acid phenethyl ester (CAPE), which has been demonstrated to have anti-inflammatory, antiproliferative, anticancerogenic, and antioxidant effects, and vitamin E on IL-1 beta and IL-6 in bleomycin-induced (BLM-induced) pulmonary fibrosis in rats. Thirty-two Sprague-Dawley rats were divided randomly into four groups as untreated control, bleomycin, bleomycin + CAPE, and bleomycin + vitamin E groups. At the end of the treatment, blood IL-1 beta and IL-6 levels were quantified. Bleomycin application to the rats resulted in a significant increase in the cytokine levels as compared to the controls. Administration of CAPE and vitamin E prevented the increase of blood IL-1 beta and IL-6 levels compared to the rats treated with bleomycin alone. Data presented here suggest that CAPE and vitamin E play a protective and moderator role against BLM-induced lung injuries by decreasing the primary inflammatory cytokines, such as IL-1 beta and IL-6. (c) 2006 Elsevier Inc. All rights reserved

Assessing the effects of wind farms on soil organic carbon.

Wind energy is considered one of the cleanest and most sustainable resources among renewable energy sources. However, several negative environmental impacts can be observed, unless suitable sites are selected for the establishment of wind farms. The aim of this study is to determine the change in the soil organic carbon (SOC) stock resulting from land cover changes that were caused by wind farm establishments in the Karaburun peninsula. Within the scope of the study, remote sensing and geographic information system technologies were utilized. Maximum likelihood algorithm, one of the supervised classification techniques, was used to classify the land cover, and Normalized Difference Vegetation Index (NDVI) analyses were performed to determine land cover changes. The findings were correlated with the “Turkey Soil Organic Carbon Project” data. As a result, depending on the establishment of wind farms in the Karaburun Peninsula, a total decrease of 18,330.57 tons of SOC in the study area between 2000 and 2019 was determined. It should be taken into consideration that besides many other negative effects (effects on human health, effects on the ecosystem, effects on animals, etc.), land cover changes caused by wind farms may indirectly cause important problems such as climate change. Recently, this situation shows that there is an important dilemma in terms of current implementations. Wind farms are the most invested renewable energy sources and alternative energy supply to fossil fuels in terms of preventing climate change. However, the results of this study have reviewed that lack of proper approaches and methods to establish wind farms may result in various problems such as physical, chemical, and biological degradations and an increase in the amount of atmospheric carbon. Consequently, the investments in renewable energy sources should be comprehensively reevaluated in terms of current technologies, quality in the scope of environmental impact assessment and strategic environmental assessment processes, legal regulations and national policies, long-term environmental costs, etc

Colloidal and viscoelastic properties of expanded perlite dispersions

In this study, structural properties of unexpanded perlite and expanded perlite particles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis techniques. Electrokinetic properties of unexpanded perlite and expanded perlite particles in polar (water) and non-polar (silicone oil) media were determined using zeta ()-potential measurements as functions of time, pH, valences of electrolytes, type of surfactants, and temperature. Antisedimentation stabilities of the unexpanded perlite and expanded perlite particles dispersed in silicone oil were determined as a function of temperature at various volume fractions (phi=5\%-25\% v/v). Viscoelastic properties of expanded perlite particles dispersed in silicone oil were investigated by creep and creep-recovery tests under externally applied electric field strengths. As a result, the -potential and antisedimentation stability values revealed that colloidal stabilities of the expanded perlite particles were high enough to be used as smart electrorheological material in long time durations. Expanded perlite/silicone oil dispersion behaved as a viscoelastic material and exhibited a reversible nonlinear viscoelastic deformation under applied electric field and showed a vibration damping capability for potential industrial applications

Determination of the nighttime light imagery for urban city population using DMSP-OLS methods in Istanbul

© 2020, Springer Nature Switzerland AG.Demography researchers and scientists have been effectively utilizing advanced technologies and methods such as geographical information systems, spatial statistics, georeferenced data, and satellite images for the last 25 years. Areal interpolation methods have also been adopted for the development of population density maps which are essential for a variety of social and environmental studies. Still, a good number of social scientists are skeptical about such technologies due to the complexity of methods and analyses. In this regard, a practical intelligent dasymetric mapping (IDM) tool that facilitates the implementation of the statistical analyses was used in this study to develop the population distribution map for the Istanbul metropolitan area via night light data provided by the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) and the census records of the study area. A population density map was also produced using the choropleth mapping method to enable to make a comparison of the traditional and intelligent population density mapping implementations. According to the dasymetric population density map, 38.5% of the study area fell into sparse density category while low, moderate, high, and very high population density class percentages were found to be 9.4%, 5.5%, 2.9%, and 0.1% respectively. On the other hand, the percentages of the same population density classes ranking from sparse to very high in the choropleth map were determined to be 90.7%, 7.3%, 1.7%, 0.3%, and 0%. In the change analysis made as a result of the classification, the changes between the city area and the population were revealed. During this period, the city area and population grew. Spatial change has also been interpreted by comparing it with population changes. There appears to be a remarkable increase in both surface area and population. It is observed that the increase is especially in the south and northwest of the city. With the population increase, the number of new residential areas has increased. It is thought that behind this growth, there are different reasons besides the effect of the increase in residential areas. When the environmental awareness of people has increased more than in the past centuries, new solutions should be produced in order to be more controlled, smart, and sustainable while planning the cities of the future. Considering that the development of technology and remote sensing techniques is progressing in parallel with this technology, this study in which GIS technologies integrated with satellite images are used, it is thought that it will contribute positively to the studies in this area in terms of regular development of urban areas, increasing the opportunity to make fast and correct decisions, and creating infrastructure for studies such as monitoring and prevention of illegal housing