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Valproic acid is an antiepileptic drug associated with skin-related issues like excessive hair growth, hair loss, and skin rashes. In contrast, Moringa oleifera, rich in nutrients and antioxidants, is gaining popularity worldwide for its medicinal properties. The protective properties of M. oleifera extract against skin-related side effects caused by valproic acid were investigated. Female rats were divided into control groups and experimental groups such as moringa, sodium valproate, and sodium valproate + moringa groups. A 70% ethanolic extract of moringa (0.3 g/kg/day) was given to moringa groups, and a single dose of sodium valproate (0.5 g/kg/day) was given to valproate groups for 15 days. In the skin samples, antioxidant parameters (such as glutathione, glutathione-S-transferase, superoxide dismutase, catalase, and total antioxidant capacity), as well as oxidant parameters representing oxidative stress (i.e. lipid peroxidation, sialic acid, nitric oxide, reactive oxygen species, and total oxidant capacity), were examined. Additionally, boron, hydroxyproline, sodium-potassium ATPase, and tissue factor values were determined. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was also carried out for protein analysis in the skin samples. The results showed that moringa could increase glutathione, total antioxidant capacity, sodium-potassium ATPase, and boron levels, while decreasing lipid peroxidation, sialic acid, nitric oxide, total oxidant capacity, reactive oxygen species, hydroxyproline, and tissue factor levels. These findings imply that moringa possesses the potential to mitigate dermatological side effects. [ABSTRACT FROM AUTHOR]

In this study, pectin was extracted from the pistachio hull using two methods: conventional extraction and ultrasound-assisted extraction. Water and citric acid solution were tested separately as extraction solvents in both conventional and ultrasound methods. The highest yield (32.3 ± 1.44%) was obtained using a citric acid solution in the conventional extraction method. The pectin extracted with this method had 38.94 g acid per 100 g dry pectin extract. The galacturonic acid and ash contents were 65.81 ± 1.51 and 1.57 ± 0.03%, respectively. The pistachio hull pectin was under the low methoxy pectin group with a 19.29 ± 0.41% degree of esterification. The emulsifying property of the pectin extracted was investigated in an oil-in-water emulsion system at six different pectin concentrations (2, 4, 5, 6, 8, and 10% w/w) and at a fixed oil ratio (20% w/w). Emulsion performance was investigated in terms of emulsion stability, microstructural characteristics, droplet size, and rheological properties. The most stable emulsion was obtained at a 6% pectin concentration. The emulsifying activity index, emulsion stability index, droplet size, consistency index, and flow behavior index were 172.85 ± 0.59 m2/g, 158.28 ± 3.41 min, 6.08 ± 0.04 µm, 0.72 ± 0.001 Pa·sn, and 0.752 ± 0.005 at this concentration, respectively. [ABSTRACT FROM AUTHOR]

Water is being contaminated by different oxyanions which have many negative effects on the human body. This study deals with the adsorptive removal of Cr2O7−2, AsO4−3, and ClO4−1 oxyanions from water using diethanolaminomethylcalix[4]arene bonded silica (DBS) resin. The capacity of DBS resin for the removal of oxyanions was checked through batch method under the optimized parameters such as pH, adsorbent dosage, concentration of oxyanions, and effect of temperature. The experimental data were analyzed through Langmuir, Freundlich, and Dubinin–Radushkevitch (D–R) adsorption isotherm models and the Langmuir model was the best fit model with a good correlation coefficient (R2 0.998). The thermodynamic and kinetic studies were performed to check the mechanism and adsorption pathway of oxyanions onto DBS resin. The thermodynamic parameters such as (ΔH°, ΔS°, and ΔG°) describes that the adsorption of oxyanions was spontaneous and endothermic and followed by pseudo second order kinetic models very well. The reusability of resin was also checked and it has been observed that after 27 cycles only 2% loss in adsorption capacity. Moreover, the oxyanions were optimized at the B3LYP/LANL2DZ/6-311++G (d,p) level using G09W software to analyze the oxyanions-DBS interactions phenomenon. [ABSTRACT FROM AUTHOR]

In the current study, a simple, cheap, and fast analytical procedure, termed ultrasonic-assisted cloud point microextraction (UA-CPME), combined with UV-VIS spectrophotometry, was developed for the pre-concentration and identification of Ponceau 4R in some beverage samples. Ponceau 4R was extracted from aqueous solution using polyethylene glycol mono-p-nonylphenyl ether (PONPE 7.5) as extraction solvent in the presence of Cu(II) at pH 6.0. Variables influencing the UA-CPME extraction efficiency such as pH, metal type and amount, temperature, ultrasonic effect, solvent type, non-ionic surfactant type and concentration were optimised in detail. Under optimum conditions, the analytical properties of the developed method were as follows: linear working range, 20–750 μg L−1; limit of detection, 6.5 µg L−1; and the pre-concentration factor, 200. The relative standard deviation (RSD%) obtained for 50 µg L−1 (n = 5) of Ponceau 4R was 2.9%. The accuracy and precision of the method were evaluated by intra-day and inter-day studies. Finally, the developed method has been successfully applied to the separation and identification of Ponceau 4R in the selected samples and the recoveries ranged from 94.3 to 104.2% [ABSTRACT FROM AUTHOR]

A fast, cheap and green analytical method was developed for the determination and extraction of curcumin in tea, honey, and spices using deep eutectic solvent-assisted emulsification liquid–liquid micro-extraction (DES-ELLME) coupled to UV-VIS spectrophotometry. Quantitative extraction of curcumin from the sample was obtained by the DES, which was prepared by mixing choline chloride and maltose in a 1:3 molar ratio. Response surface design was used for the optimisation of significant experimental parameters including sample pH, amount of extraction solvent, amount of emulsifier solvent and vortex time. The optimum conditions obtained were pH 4.25, 762.5 μL of DES, 107.5 mL of tetrahydrofuran and 3.4 min vortex time, while keeping centrifugation speed fixed at 4000 rpm, 5 min. Under the extraction conditions obtained, analytical features such as calibration equation, limit of detection, enrichment factor, and linearity were Abs = 6.5 × 10−4 [Curcumin, ng mL−1]-1.2 × 10−5, 0.1 ng mL−1, 114 and 0.4–120 ng mL−1, respectively. Moreover, the repeatability and reproducibility of the DES-ELLME method, expressed as relative standard deviation (RSDs%), varied in the ranges of 1.4–3.0% and 2.0–4.3%, respectively. Finally, the proposed method was successfully applied to the extraction and determination of curcumin from prepared samples. The relative mean recovery ranged from 92.3% to 104.4%. [ABSTRACT FROM AUTHOR]

In this research article, a novel and green deep eutectic solvent-based microextraction (DES-ME) procedure based on chemometric-assisted (CA) optimization was developed for the extraction of caffeine in foods and beverages prior to its spectrophotometric determination. Ultrasound was used to accelerate the extraction of caffeine. Deep eutectic solvents (DES), prepared in an ultrasonic bath at 20–60 min for 60–80°C, were used as extraction solvents. The important experimental variables (pH, DES amount, temperature, sonication time and metal concentration) were modelled and optimized using response surface methodology (RSM) based on central composite design (CCD). Under the optimum conditions, the proposed method allowed the determination of caffeine with limits of detection (LOD, 3sblank/m) and quantification (LOQ, 3sblank/m) of 7.5 and 25.0 µg L−1, respectively. For 40 µg L−1 and 100 µg L−1 of caffeine (n = 5), relative standard deviations (RSDs%) and recoveries% were 1.2–1.6% and 96.7–98.2%, respectively. Validation studies (accuracy, precision, trueness, reliability and selectivity) of the method were performed before the analysis of real samples. The results showed that the combination of the CCD with the DES-ME can be considered as a new perspective for the extraction and determination of caffeine in foods and beverages. [ABSTRACT FROM AUTHOR]

In this study, a simple, pH-controlled, and natural deep eutectic solvent-based microextraction (NADES-ME) procedure is proposed before the spectrophotometric analysis of methylmercury (MeHg) and total mercury in fish and environmental waters. The method is based on charge-transfer sensitive ion-pair formation between MeHg and 3-(dimethylamino)-7-(methylamino)phenothiazin-5-ium chloride (Azure B – AzB) in the presence of chelating citrate-phosphate buffer at pH 6.0, and then extraction of the formed ion-pair complex with the NADES. The important variables affecting extraction efficiency were evaluated and optimised. At optimal conditions (300 µL of 1.0 × 10−3 mol L−1 AzB, 600 µL NADES (betaine-sorbitol, 1:3) containing 10% water (v/v) as extractant, 375 µL acetonitrile as aprotic solvent for sonication of 7 min at power of 300 W/40 kHz, and centrifugation at 4000 rpm for 3 min, respectively), the figures of merit for MeHg include a good linearity in the concentration range of 0.7–340 µg L−1, limits of detection and quantification of 0.25 and 0.83 µg L−1, and pre-concentration and sensitivity enhancement factors of 120 and 95, respectively. Figures of merit for total Hg (iHg, where Hg22+ ions are predominantly present in natural oxygen-rich waters such as freshwaters and seawater as well as elemental Hg and Hg2+ ions at very low amounts) after pre-oxidation at pH 5.0 include linearity range of 3–270 µg L−1 with limits of detection and quantification of 0.92 and 3.10 µg L−1, and pre-concentration and sensitivity enhancement factors of 120 and 35, respectively. The reliability (with recovery of 92–98.7% and RSD of 1.9–5.5%) was statistically validated by analysis of two standard reference materials (SRMs) with and without spiking. The method was successfully applied to the speciation analysis of total Hg, iHg and MeHg in fish and environmental waters. [ABSTRACT FROM AUTHOR]

In this study, a simple, fast and eco-friendly ultrasound-assisted-cloud point extraction method for extraction and pre-concentration of zinc, nickel and cobalt from vegetables and foods prior to their determination by flame atomic absorption spectrometry (FAAS) was proposed. Ultrasound energy was used to shorten extraction time and reduce steps needed or to improve selectivity. The method is based on complex formation of metal ions with carmine in presence of cationic surfactant at pH 5.0, and then extraction of their hydrophobic complexes into the micellar phase of Igepal CO-630 as extractant. After optimisation, calibration curves for Zn, Co and Ni were linear in the range of 2-120, 2-220 and 2-180 μg kg−1, respectively. Limits of detection, which is described as ratio of 3×standard deviation of 12 replicate measurements of blank analysis to slope of calibration curves, were 0.5, 0.6 and 0.6 μg kg−1 for Zn, Ni and Co, respectively. Relative standard deviations (RSDs%, n: 5) for 25 μg kg−1 of each analyte were less than 3.1%. The recovery rate was higher than 94% with a lower RSD than 3.1% for five replicate measurements of 25 μg kg−1 of each analyte. The accuracy was verified using two different standard reference materials (SRM 1570a-Trace elements in spinach leaves and SRM 1548a-Typical diet), and the results were in good agreement with the certified values. The method was applied to the determinations of Zn, Ni and Co in vegetables and foods by FAAS. [ABSTRACT FROM AUTHOR]

Acrylamide (AAm) is a carcinogenic chemical that can form in thermally processed foods by the Maillard reaction of glucose with asparagine. AAm can easily be formed especially in frequently consumed chips and cereal-based foods depending on processing conditions. Considering these properties of AAm, a new, simple and green method is proposed for the extraction of AAm from thermally processed food samples. In this study, an ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, [Bmim][BF4]) as extractant was used in the presence of a cationic phenazine group dye, 3,7-diamino-5-phenylphenazinium chloride (PSH+, phenosafranine) at pH 7.5 for the extraction of AAm as an ion-pair complex from selected samples. Under optimum conditions, the analytical features obtained for the proposed method were as follows; linear working range, the limits of detection (LOD, 3Sb/m) and quantification (LOQ, 10Sb/m), preconcentration factor, sensitivity enhancement factor, sample volume and recovery% were 2.2–350 µg kg−1, 0.7 µg kg−1, 2.3 µg kg−1, 120, 95, 60 mL and 94.1–102.7%, respectively. The validity of the method was tested by analysis of two certified reference materials (CRMs) and intra-day and inter-day precision studies. Finally, the method was successfully applied to the determination of AAm levels in thermally processed foods using the standard addition method. [ABSTRACT FROM PUBLISHER]

Both comparison and optimization of two sample preparation methods (probe and bath) based on leaching of lead (Pb), zinc (Zn), manganese (Mn) and nickel (Ni) from bio-collector sprouts (Pinus sylvertrisL.,Picea orientalisL.,Thuja orientalisL.) under ultrasonic effect has been examined. The best analytical conditions influencing leaching such as sonication times, acid type, acid concentrations, ultrasound amplitude and sample position (wet, dry and grinding) were determined. Leachatants obtained upon sonication were directly nebulized into an air-acetylene flame for fast metal determination by atomic absorption spectrometry (AAS). Optimum conditions for ultrasonic metal leaching were as follows: a 15 min for probe or 30 min for bath sonication time, wet sample position, nitric acid (HNO3) solvent, 1% (w/v) for probe or 2% (w/v) for bath solvent concentration and 20% amplitude for probe. Comparable results for the ultrasonic leaching with probe (UL-P) and the ultrasonic leaching with bath (UL-B) for metals in certified reference material and bio-collectors have been obtained. Besides, UL-P reduces the time required for all treatments with UL-B approximately from 30 min to 15 min. The accuracy of methods was tested either by comparing obtained results with those of ashing method (AM) or by application on a certified reference material (CRM-7, Tea Leaves). The recoveries of metals using CRM-7 ranged from 94% to 104% for UL-P and 91% to 101% for the UL-B. The precision variance either between UL-P and UL-B or UL-P and AM was not significant at 0.05 probability for all metals. The relative standard deviation % was obtained between 3.4–7.6% (n = 3) and 4.7–9.5% (n = 3) for UL-P and UL-B, respectively, depending on the analyte. [ABSTRACT FROM AUTHOR]

During its final two centuries, the Ottoman Empire failed to introduce an “exit strategy” from the Middle East. On account of this uneasy disengagement, Republican Turkey turned back and followed an anti-revisionist policy toward the region. In the 1920s, the revolutionary leadership of the Turkish Republic focused on internal reformation and modernization programs, which made a structural transformation in domestic politics and systemic change that further forced Turkish governments not to pursue an active policy in the region. During the Cold War, Turkey's Middle East policy was not viewed as friendly toward the Middle East while there was a strong security ties with Iran, especially in Central Treaty Organization. However, Turkey followed a more aggressive and coercive entrance strategy toward the region by the end of the Cold War. The Justice and Development Party has made a shift and attempted to exercise soft power policies to normalize its relations with Arab nations and Iran by improving societal and economic interdependence relations. In order to understand the new activism in Turkish–Iranian relations, it is necessary to provide a historical context of the changing dynamic of regional politics by analyzing threat perceptions and security alignments from the perspective of developing Turkish–Iran relations. [ABSTRACT FROM PUBLISHER]

Background: Augmentation index (AIx) and pulse wave velocity (PWV) are early markers of atherosclerotic vascular changes and also have been shown to be predictive of cardiovascular disease and total mortality. The aim of our study was to evaluate the relationship between PWV and AIx-HR75, which is the corrected form of AIx according to a heart rate of 75 beats/min, echocardiographic parameters and biochemical parameters in chronic hemodialysis (HD) patients. Subjects and methods: AIx-HR75 and PWV were measured in 556 HD patients by applanation tonometry using the SphygmoCor device. Results: The mean PWV and AIx-HR75 values of the study group were 10.2 ± 2.4 and 28.4 ± 10.2 m/s. A positive correlation was found between PWV and AIx-HR75 ( r == 0.214, p == 0.000). AIx-HR75 correlated with age ( r == 0.093, p == 0.028), body surface area (BSA) ( r == −0.194, p == 0.000), mean arterial pressure (MAP) ( r == 0.335, p == 0.000), pulse pressure (PP) ( r == 0.212, p == 0.000), cardiothoracic index ( r == 0.155, p == 0.016), and presence of left ventricular hypertrophy ( r == 0.152, p == 0.001). PWV correlated with MAP ( r == 0.208, p == 0.000), PP ( r == 0.098, r == 0.021), left ventricular mass ( r == 0.105, p == 0.023), and predialysis sodium level ( r == −0.105, p == 0.023). In the multivariate analyses, PWV was associated with MAP ( t == 3.78, p == 0.000), presence of diabetes ( t == 3.20, p == 0.001), and predialysis sodium level ( t == −2.06, p == 0.040), and AIx-HR75 was associated with age ( t == 2.48, p == 0.014), female sex ( t == 3.98, p == 0.000), BSA ( t == −2.15, p == 0.033), and MAP ( t == 7.02, p == 0.000). Conclusion: There is a strong association between MAP and arterial stiffness parameters in HD patients. We feel that efficient control of blood pressure could lead to reduced arterial stiffness in HD patients. [ABSTRACT FROM AUTHOR]

This self-report study investigated 274 pre-service teachers' attitudes toward students with learning and behavioural difficulties (LBD) and the factors that predict their attitudes. Using four scenarios describing students with LBD, we investigated the degree to which pre-service teachers' open-minded thinking dispositions, readiness to learn about students with LBD, beliefs about the role of regular classroom teachers in providing for these students, and emotions in relation to dealing with these students' difficulties predict their likelihood of engaging in punitive reactions (e.g., giving a timeout) and planned behaviours (e.g., adapting instruction). Teachers with more open-minded thinking dispositions and readiness to learn about students with LBD reported a higher likelihood of adapting instruction. Pre-service teachers' negative emotions partially mediated the relationship between their beliefs and punitive reactions and fully mediated the relationship between their open-minded thinking dispositions and punitive reactions. [ABSTRACT FROM AUTHOR]

Heavy metal contents of street dust samples collected from seven sites located in and around urban areas in Sivas city, Turkey, were determined by atomic absorption spectrometry after digestion using a mixture of acids. The results of the analyses were used to determine major sources and magnitude of heavy metal pollution, and were compared with the background values. The mean concentration levels of lead (Pb), zinc (Zn), nickel (Ni), copper (Cu), and cadmium (Cd) were found to be 197, 206, 68, 84, and 2.6 μg g[SUP-1], respectively. High concentrations of heavy metals were detected in street dust samples collected in close proximity to emission sources such as motor-vehicle emissions and industrial area. The heavy metal levels in urban street dust samples were several times higher than the background levels. After heavy metal pollution factors of each site were determined, their possible pollutant sources were determined. The levels of the metal ions were compared with the mean worldwide contents of the street dust samples. The precision of method varied between 2.0 and 6.8% (n = 42) as average relative standard deviation (RSD %) depended on the analyte and nature of the sample. [ABSTRACT FROM AUTHOR]

The heavy metal levels in bio-collector (Fubaceae Rabinia Pseudoacacia L. sprouts) samples collected from seven sites, which had the characteristic properties of the Sivas city, Turkey, in year 2000, have been determined by atomic absorption spectrometry (AAS), after the bio-collector sprouts were prepared for analysis by bio-collector ultrasonic leaching method (BC-ULM). The results of the analyses were used to determine major sources and magnitude of heavy metal pollution. The mean concentration levels of Pb, Cu, Ni, Zn and Cd were found to be 6.8, 5.5, 6.7, 12.4 and 0.20~tg/g fresh bio-collector, respectively, for September 2000. The highest levels of the heavy metals at the sites affected by industrial emissions and heavy traffic were noted. The heavy metal levels in urban bio-collectors were several times higher than the background levels. After heavy metal pollution factors of catch site were determined, their possible major pollutant sources were discussed. [ABSTRACT FROM AUTHOR]

Snow samples from six sites located in and around urban areas in Sivas city, Turkey, were collected in the winter of 2000. After ultrasonic leaching of the melted snow solutions, they were analysed for heavy metals (Mn, Zn, Pb, Cu, Ni and Cd) by atomic absorption spectrometry (AAS). The results of the analyses were used to determine major sources and magnitude of heavy metal pollution. Besides, it was compared with the heavy metal concentrations in the urban snow with those of background areas to see whether they could be used as an effective indicator of urban atmosphere pollution. High concentrations of heavy metals were detected in snow samples collected in close proximity to emission sources such as motor-vehicle emissions, combustion of coal and fuel-oil, industrial area. The heavy metal levels in urban snow were several times higher than the background levels. After heavy metal pollution factors of each site were determined, their possible pollutant sources were detected. Our findings show that, data on the heavy metal concentrations in snow are a reliable guide to the degree of air pollution, and can be used as a simple and effective indicator of urban atmosphere pollution. The precision of method varied between 1.22 and 5.62% (n = 54) as average relative standard deviation % (RSD %) depended on the analyte and nature of the sample. [ABSTRACT FROM AUTHOR]

A correction to the article Pre-Service Teachers' Open-Minded Thinking Dispositions, Readiness to Learn and Attitudes About Learning and Behavioural Difficulties in Students," that was published in the May 2010 issue of the periodical is presented.