Effects of oleaster flour supplementation in total phenolic contents,antioxidant capacities and their bioaccessibilities of cookies

Food Science and Biotechnology - In presented study total phenolic contents, antioxidant capacities and their bioaccessibilities from cookies supplemented with oleaster flour were investigated....     

Dry eye and Meibomian gland dysfunction with meibography in patients with lamellar ichthyosis

Purpose

To evaluate the dry eye findings and Meibomian gland dysfunction as demonstrated with meibography in patients with lamellar ichthyosis.

The false positive effect of residue of sulphur sources on dithiocarbamate analysis based on CS2 measurement

Turkey plays an important role in the international trade of apricots as it has the largest production rate in the world. Since the sulphurisation process is allowed to be used for different products, the effect of residual sulphur and its compounds (which can be found in products as pesticide residues or additive residues) on the positive detection of carbon disulphide (CS₂) still creates a big challenge in international trade. Therefore, the main objective of the present study was to investigate the effects of residues of sulphur or sulphur compounds on dithiocarbamate analysis methods based on CS₂ measurement. In this study, apricots were chosen since they contain sulphur residues as a result of the sulphurisation process. Sulphur dioxide and dithiocarbamate analyses were conducted on dried apricots prepared with the sulphurisation process (SA) and without the sulphurisation process (NSA); analysis was by two different accredited laboratories. No of pesticide was applied to either SA or NSA samples. Although some of the NSA samples had <LOQ values, approximately 70 ± 32 mg/kg SO₂ and 0.061 ± 0.021 mg/kg dithiocarbamate were detected for NSA samples. On the other hand, for the SA sample group, 927–2915 mg/kg of SO₂ and 0.265–0.825 mg/kg of dithiocarbamate were detected. Furthermore, a strong correlation between residual sulphur and dithiocarbamate values was observed. This study showed that the analysis method based on CS₂ measurement may lead to false positive results for dithiocarbamates when residues of sulphur or sulphur compounds are found in products as pesticide or additive residues. Therefore, residual sulphur compounds as a result of the sulphurisation process (which is not considered during the evaluation of products) must be taken into account during the evaluation of products for dithiocarbamates.     

Opto-electrical and morphological characterization of water soluble conjugated polymers for eco-friendly hybrid solar cells

Solid-state Dye-Sensitized Solar Cells (ss-DSSCs) are promising candidates for future low cost photovoltaic energy generation and are based on polymer/metal oxide donor/acceptor heterojunctions. However, a crucial drawback of hybrid solar cells is the use of environmental unfriendly solvents, such as toluene, chloroform, chlorobenzene, etc. in the phase of preparation. In this work towards eco-friendly processing, we use water as a solvent in the preparation of the photo-active layer for hybrid solar cells. We demonstrate eco-friendly hybrid polymer/titania solar cells consisting of water soluble polythiophene as light-absorber, donor and Hole Transporting Layer (HTL), above a TiO₂ layer that acts as an acceptor and electron conductor. The water soluble conjugated polymer materials are studied in terms of their opto-electrical and morphological properties, leading to a better understanding of the resulting photovoltaic performance. An alternative new processing method in device preparation is introduced; yielding prototype solar cells with an efficiency of 0.7%. This promising solar cell device performance can be considered as a proof-of-principle for future eco-friendly solar cells.     

Pilot study on lower nitrosamine smokeless tobacco products compared with medicinal nicotine.

Smokeless tobacco (ST) products have the potential to be used as a harm reduction method for cigarette smokers. These products can deliver significantly less toxicants than cigarettes, although they are not toxicant free nor harmless. It is important to examine potential health risks and benefits of these products. These two small pilot studies examined the effects of two different ST products (Exalt and Ariva) compared with medicinal nicotine, another potential harm reduction product. Dependent, healthy adult cigarette smokers, who were motivated to quit smoking, underwent 1 week of baseline smoking measurement. They were then asked to quit smoking and were randomly assigned to use either an ST product or a medicinal nicotine lozenge (MNL, Commit) for 2 weeks, then crossed over to use the other product for 2 weeks. In the last week, following the sampling phase, subjects could choose the product they wished to use. Assessments were made repeatedly during baseline cigarette use and throughout the 5 weeks of treatment. Outcome measures included biomarkers for tobacco exposure and subjective, physiological, and behavioral responses. Tobacco-specific carcinogen uptake was greater from Exalt than from the MNL, and was comparable between the MNL and Ariva. Physiological effects and subjective effects on withdrawal and craving were comparable among Exalt, Ariva, and the MNL. Ariva was preferred over the MNL, which was preferred over Exalt. With the exception of medicinal nicotine products, low-nitrosamine ST products have the greatest potential to result in reduced toxicant exposure compared with other combustible reduced exposure products and have promise for reducing individual risk for disease. However, the population effect of marketing of such products as reduced exposure/reduced risk is unknown. The need for further research in this area and regulation of tobacco products is evident.     

Coprecipitation of Ni(2+), Cd(2+) and Pb(2+) for preconcentration in environmental samples prior to flame atomic absorption spectrometric determinations

A coprecipitation procedure has been presented prior to flame atomic absorption spectrometric determination of nickel, cadmium and lead ions in environmental samples. Analyte ions were coprecipitated by using copper hydroxide precipitate. The influences of some analytical parameters like amounts of copper, sample volume, etc., on the recoveries of the analytes were investigated. The interference of other ions was negligible. Under the optimized conditions, the detection limits (3 sigma, n=15) of lead(II), nickel(II) and cadmium(II) were 7.0, 3.0 and 2.0 microg/L, respectively. The proposed method has been successfully applied for the determination of traces of Ni, Cd and Pb in environmental samples like tap water.     

Determination of secondary transitions and thermodynamic interaction parameters of poly (ether imide) by inverse gas chromatography

Summary The retention diagrams of poly(ether imide) for ethyl benzene, n-propyl benzene, isopropyl benzene, chloro benzene, n-butyl acetate, tert-butyl acetate, isoamyl acetate, n-nonane, n-decane, n-undecane, n-dodecane and n-tridecane were obtained by inverse gas chromatography technique. In this work, the slope changes on the diagram were assigned as secondary transitions. The secondary transition temperatures obtained by inverse gas chromatography technique are in good agreement with the ones obtained by thermally stimulated depolarization current in the literature. Specific retention volume, V_g⁰, the weight fraction activity coefficients of the solvents at infinite solution, Ω₁^∞, Flory-Huggins polymer-solvent interaction parameters,χ₁₂^∞, equation-of-state polymer-solvent interaction parameters,χ₁₂^*, effective exchange energy parameters, X_eff were determined. Later, the partial molar heat of sorption, and the partial molar heat of mixing, were obtained. The solubility parameter of poly(ether imide), δ₂ was determined as 10.7 (cal/cm³)^1/2 by extrapolation of the δ₂ values obtained by considering the free volume effects from studied temperature range to room temperature.     

Polymeric nanopore membranes for hydrophobicity-based separations by conformal initiated chemical vapor deposition

High-aspect ratio hydrophobic, cylindrical nanopores having diameters as low as 5 nm are rapidly fabricated using conformal vapor deposition of fluorinated polymeric layers into porous track-etched polycarbonate membranes. The resultant selectivity of these membranes for pairs of small molecules of similar size, but of different hydrophobicity, arises from solute-pore wall interactions emphasized by confinement. Increasing selectivity was observed as pore diameter decreased and as the surface of the pore became more hydrophobic. Cylindrical pores provided higher selectivity than bottleneck-shaped pores having the same minimum diameter. A maximum selectivity of 234 was achieved between mesitylene and phloroglucinol by the best performing membrane. Membranes with small fluorinated pores exhibited an effective cutoff based on the polar surface area of the molecules, with limited correlation with solute size. This technology could lead to a new generation of membrane separations based on specific interactions.     

Effect of alkali metal hydroxides on the morphological development and optical properties of ceria nanocubes under hydrothermal conditions

Nanocrystalline cerium(LV) oxide (CeO2, ceria) particles were produced via the hydrothermal treatment of cerium nitrate hexahydrate with various alkali metal hydroxides (MOH: M = Li, Na, K). Experimental conditions such as [MOH], reaction temperature, and reaction time were studied. Particle morphology as well as size of crystallites was precisely controlled by choice of experimental conditions. While rod-shaped particles were obtained at 120 degrees C, well-defined nanocubes were formed at higher temperatures regardless of the choice of MOH. Examination of particle growth kinetics, in the final stages of crystallization, showed that particle growth rate is controlled by two different mechanisms. Grain boundary diffusion controls the particle growth in the presence of NaOH with an activation energy of 113.8 kj/mol and surface diffusion for LiOH ad KOH with the activation energy of 43.0-150.9 kj/mol, respectively. In addition, the particles exhibit strong violet and blue emissions at 400 nm and 370 nm. The former emission originates from excitation of a wide band gap of CeO2. The latter one is attributed to the trivalency of the cerium ion and appears to be sensitive to all the experimental conditions studied. Both extending reaction time and increasing temperature reduce the intensity of the 370 nm emission and increase the intensity of the 400 nm emission.     

Why Turks do not use seat belts? An interview study

Despite the effectiveness of seat belt use and legislation, seat belt use rate is low in Turkey. The aim of this study was to investigate the motives to use and not to use a seat belt in different traveling conditions in a sample of car drivers and passengers. Interviews were made face to face with 221 interviewees from different age and occupation groups. Frequently reported reasons for using a seat belt were traveling conditions, safety, situational conditions, habit of using a seat belt, and avoiding punishment. Frequently reported reasons for not using a seat belt were situational conditions, not believing in the effectiveness, discomfort and having no habit. Safety was the strongest predictor of reported seat belt use in both low and high risk traveling conditions. Findings suggest that seat belt campaigns should mainly emphasize seat belt's safety impact and aim at habit formation.