Determination of Aflatoxins and Ochratoxin A in Wheat from Different Regions of Turkey by HPLC with Fluorescence Detection

This study examines the occurrence of aflatoxins (AFS) and ochratoxin A (OTA) in bread and durum wheat samples. A total of 141 samples were collected from eleven different regions of Turkey. An analytical method based on liquid extraction, immunoaffinity column (IAC) clean-up followed by high performance liquid chromatography (HPLC) was used for the determination of AFs and OTA levels. As a result, AFs and OTA were detected in 2% and 9.2% of wheat samples at concentrations varying from 0.21 to 0.44 µg kg−1 and from 0.1 to 3.2 µg kg−1, respectively. Aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) were found positive in samples ranging between 0.21–0.35 µg kg−1 and 0.094 µg kg−1, respectively. However, none of the samples contained aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2). The study also recommended that contamination levels in wheat and wheat-based products should be routinely monitored in greater sample numbers to insure food safety

RE: 3 T magnetic resonance diffusion tensor imaging and fibre tracking in cervical myelopathy

[No abstract available

Discriminative role of CT in exudative and transudative pleural effusions

[No abstract available

Improved oil recovery application in limestone reservoirs using alkaline solutions

In this research, the effect of sodium hydroxide (NaOH) and sodium silicate (NaSiO4) solutions for the improved oil recovery of Raman crude oil was investigated using a one-dimensional unconsolidated limestone reservoir model. The results of displacement tests showed that sodium hydroxide (NaOH) and sodium silicate (NaSiO4) solutions were not effective on incremental oil recovery. It was also observed that injection flow rate of alkaline solution has minimum effect on Raman crude oil in scope of oil recovery achieved. The optimum injection flow rate was found as 220 cc/h for Raman crude oil

Determination of formation damage in limestone reservoirs and its effect on production

Reduction of injectivity of wells by formation damage can be of considerable magnitude during waterflooding of oil reservoirs. Variation of pH of the flowing fluid is an indicator of chemical activity occurring in the formation. High pH promotes formation damage by particle deposition within the porous media and consequently particle bridging at the pore throats. Permeability reduction is used as quantitative measure of formation damage. In this paper, the results of core flow experiments in limestone formations are presented. Effluent pH and Cl concentrations are measured at the outlet of the porous medium. Brines are prepared with sodium, calcium and potassium salts (NaCl, CaCl2, KCl). In limestone formations, formation water, which is used in injection, and artificially prepared brine in various concentrations, caused the permeability reduction. High pH values in produced water caused the permeability reduction and consequently the pores are plugged and formation damage is observed. In alkaline flooding experiments, permeability reduction is observed as a result of high pH alkaline fluids. The permeability reduction is minimized using brines of NaCl, CaCl2 and KCl mixtures and high oil recoveries are obtained. Suspended solid particles are released and moved with injection water when salt concentration drops below the critical salt concentration, causing the permeability reduction and formation damage. Experiments below the critical salt concentrations, resulted in a reduction in permeability values in consolidated/unconsolidated limestone samples, whereas, high pH value solutions caused a reduction in permeability values, plugged the pores and resulted in formation damage

Group psychotherapy with female-to-male transsexuals in Turkey

The change in Turkish law to allow local sex reassignment surgery was passed in May 1988. By law, a candidate for such surgery must obtain a medical certificate attesting that the operation is necessary. However, the law does not specify conditions for granting such a certificate, so any physician can give a certificate based on his own criteria. Sex reassignment surgery can therefore be performed without preoperative psychiatric evaluation and preparation. This is a report of 40 female-to-male transsexuals. They had completed psychiatric assessment and participated in group therapy. These meetings provided a valuable setting for getting to know transsexuals and their families. Participants' long, regular attendance and low dropout rate demonstrate high group cohesion. The aim of the study is to report characteristics of a group of transsexuals living in a different cultural setting from other studies of this patient population in order to identify problems of Turkish transsexuals and advocate changes in current Turkish laws for sex reassignment

Synthesis and investigation of intra-molecular charge transfer state properties of novel donor-acceptor-donor pyridine derivatives: the effects of temperature and environment on molecular configurations and the origin of delayed fluorescence

A novel series of donor-acceptor-donor (D-A-D) structured pyridine derivatives were synthesised and detailed photo-physical investigations were made using mainly steady-state and time-resolved spectroscopy techniques at varying temperatures. The investigations showed that the molecules have solvent polarity and temperature dependent excited-state configurations, confirmed in two different polarity solvents (295-90 K), i.e. methyl cyclohexane (MCH) and 2-methyltetrahdrofurane (2-MeTHF). In MCH, the investigations revealed dual fluorescence over the temperature range of 295-90 K. At 295 K, the ground-state configuration of the molecules has a partially twisted geometry as determined by DFT calculation, yet the emission originates totally from a locally excited (LE) state, however once the temperature is lowered to 90 K, the twisted molecular configuration is stabilised, and the emission originates from a fully-relaxed intramolecular charge transfer state (ICT), this is contrary to the systems where structural reorganisation stabilises ICT and this is frozen out at low temperatures. The DFT calculations revealed different ground state molecular configurations due to the presence of different electron-donating groups, e.g. the molecule including anthracene groups has a near 901 twisted geometry whereas the triphenylamine including molecule has a pyramidal geometrical folding, therefore, the decrease in temperature restricts the donor degree of rotational freedom. In 2-MeTHF solution, the fluorescence spectrum of both molecules is always of ICT character, but gradually red-shifts through the fluid to glass transition temperature (B135 K), in this case, the fluorescence occurs after structural and solvent-shell relaxations, however, upon cooling below 135 K, the spectra dramatically shift back to blue giving rise to strong emission from an ICT excited-state (but not the LE state) where the molecules have unrelaxed geometries. This significant change in the nature of the emitting species was explained with specific solvent-solute dynamic interactions in the vicinity of the solvation shell and the effect of thermal excitation of molecular vibrational modes of the C-C bond linking donor and acceptor units. Finally, we confirmed that the molecules have ICT ground-state geometry in the solid-state phase (spin-coated films), and the time-resolved decay dynamics were investigated comparing the spin-coated films (at RT and 25 K) and MCH solutions (at 295 K and 90 K)

Impact of passive smoking on uterine, umbilical, and fetal middle cerebral artery blood flows

Purpose. The aim of this study was to evaluate the influence of passive maternal smoking on blood flow velocities in arteries of the fetal-placental-maternal circulation. Materials and methods. A total of 79 pregnant women in their third trimester, including 33 passive smokers, 23 active smokers, and 23 nonsmoking controls, were enrolled in the study. Fetal biophysical indices were evaluated with B-mode scanning, whereas blood flow waveforms of uterine, umbilical, and fetal middle cerebral (MCA) arteries were analyzed with Doppler ultrasonography. Results. There were signifi cant differences among active smokers vs. passive smokers vs. controls with regard to the presence of a uterine artery diastolic notch (39.1% vs. 18.2% vs. 4.3%; P = 0.012); ratio of peak systolic/ end-diastolic velocity of fetal MCA [3.73 ±1.27 vs. 4.26 ± 1.20 vs. 5.00 ± 2.15, analysis of variance (ANOVA) P = 0.026]; resistance index of fetal MCA (0.74 ± 0.08 vs. 0.75 ± 0.07 vs. 0.80 ± 0.09; ANOVA P = 0.014); ratio of fetal MCA/umbilical artery resistance index (1.27 ± 0.20 vs. 1.24 ± 0.14 vs. 1.39 ± 0.21; ANOVA P = 0.011); and ratio of fetal MCA/umbilical artery pulsatility index (1.56 ± 0.44 vs. 1.63 ± 0.43 vs. 1.97 ± 0.54; ANOVA P = 0.046). Conclusion. Effects of passive maternal smoking on the fetal-placental-maternal unit were comparable to those with active maternal smoking as determined by the means of increased resistance in the maternal vasculature and adaptive changes of cerebroplacental circulation for maintaining fetal cerebral circulation. © 2011 Japan Radiological Society