Radon concentration measurements were performed in the city Eskişehir, Turkey in order to quantify seasonal variation. Using the assumption that indoor radon concentrations exhibit annual cyclic ...behavior, Pinel's methodology was employed to obtain seasonal correction factors (SCFs). A total of 142 dwellings had radon concentration data for each season that enabled to obtain annual average radon concentrations. Estimated SCFs were applied to each of the 142 dwellings to assess the validity of the factors. The results demonstrate that even in a very small region significant variation in radon concentrations of different dwellings can be observed, and that a good care should be taken in applying SCFs to a short-term radon measurement to obtain average annual radon concentration.
Understanding the evolution of level densities in the crossover from spherical to well-deformed nuclei has been a long-standing problem in nuclear physics. We measure nuclear level densities for a ...chain of neodymium isotopes 142,144−151Nd which exhibit such a crossover. These results represent the most complete data set of nuclear level densities to date for an isotopic chain between neutron shell-closure and towards mid-shell. We observe a strong increase of the level densities along the chain with an overall increase by a factor of ≈150 at an excitation energy of 6 MeV and saturation around mass 150. Level densities calculated by the shell model Monte Carlo (SMMC) are in excellent agreement with these experimental results. Based on our experimental and theoretical findings, we offer an explanation of the observed mass dependence of the level densities in terms of the intrinsic single-particle level density and the collective enhancement.
Indoor radon concentrations are subject to seasonal variation, which directly depends on weather conditions. The seasonal indoor radon concentrations were measured and the annual effective dose was ...estimated for the city centre of Eskisehir, Turkey. In order to reflect annual averages measurements were performed over all seasons (winter, spring, summer and autumn) including also the entire year. Measurements were carried out using Kodak-Pathe LR 115 Type II passive alpha track detectors in 220 different houses. A total of 534 measurements including measurements of different seasons were taken between 2010 and 2011. The radon concentrations for winter ranged from 34 to 531 Bq m(-3), for spring ranged from 22 to 424 Bq m(-3), for summer ranged from 25 to 320 Bq m(-3), and for autumn ranged from 19 to 412 Bq m(-3). Yearly measurements ranged from 19 to 338 Bq m(-3). In this study the average annual effective total dose from radon and its decay products was calculated to be 3.398 mSv y(-1).
Aim To investigate peroxide penetration from newer bleaching products into the pulp chamber.
Methodology Fifty extracted human maxillary central incisor teeth were separated into five groups (n = ...10). All the teeth were sectioned 3 mm apical to the cemento‐enamel junction; the intracoronal pulp tissue was removed, and the pulp chamber filled with acetate buffer. Buccal crown surfaces of teeth in the experimental groups were subjected to either a whitening strip (containing 5.3% hydrogen peroxide‐G1) or one of three paint‐on liquid whiteners (containing 19% sodium percarbonate peroxide‐G2, 18% carbamide peroxide‐G3 and 8.7% hydrogen peroxide‐G4). The teeth in the control group (G5) were exposed only to distilled water. The acetate buffer solution in each tooth was then transferred to a glass test tube after 30 min and leuco‐crystal violet and enzyme horseradish peroxidase were added, producing a blue solution. The optical density of the resultant blue colour in the tubes was measured by a UV‐visible spectrophotometer at a wavelength of 596 nm. The values were converted into microgram equivalents of HP using a spectrophotometric calibration curve. Data were analysed statistically using the Kruskal–Wallis Analysis of Variance and the Mann–Whitney U‐test.
Results Statistically significant differences were found between all of the groups (P < 0.05). Pulpal peroxide was not observed in the control group. The amount of hydrogen peroxide (μg) found in the pulp chamber of G1 (0.726 ± 0.024) > G4 (0.443 ± 0.017) > G3 (0.231 ± 0.011) > G2 (0.175 ± 0.012).
Conclusions The peroxides from the whitening strip and paint‐on whiteners penetrated into the pulp chamber to varying degrees.
The nuclear level densities and gamma-ray strength functions are the key elements for Hauser-Feshbach statistical model calculations to predict reaction cross sections which have many applications ...including astrophysics. The nuclear level densities and y-ray strength functions have been determined for 145,149,151Nd isotopes below the neutron separation energies using the Oslo method with the 144,148,150Nd(d,p) reactions. The results from the first measurements as well as planned experiments at OCL will be presented.
Thermoreversible gel of meloxicam, efficient for the treatment of joint diseases, was aimed to prepare for night application available for chronotherapy in this study. Poloxamer 407 and 188 polymers ...were used at 20-30% w/w as a vehicle in combination with different additives (polyvinylmethylether maleic anhydride copolymer, hydroxypropyl methylcellulose, polyethylene glycol 400, dimethyl sulfoxide, sodium chloride). Characterisation of prepared gels was evaluated by viscosity and texture analysis, and the effect of formulation variables on the gel formulations were evaluated by in vitro drug release and erosion studies. Between the investigated gel bases, Poloxamer 407-hydroxypropyl methylcellulose gel was found to be ideal due to its gel strength (1.560±0.0135 N), viscosity (312.3±2.06 cP) and release characteristics. These promising results could be encouraging for further studies to make it an alternative to commercial dosage forms.
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