Quaternionic Salkowski Curves and Quaternionic Similar Curves

In this paper, we give the definitions and characterizations of quaternionic Salkowski, quaternionic anti-Salkowski and quaternionic similar curves in the Euclidean spaces E^3 and E^4. We obtain relationships between these curves and some special quaternionic curves such as quaternionic slant helices and quaternionic B2-slant helices.Comment: 17 page

Long term effects of piracetam on spectral analysis of EEG in Alzheimer's disease and minimal cognitive impairment

Objective: Influence of piracetam in post-stroke aphasia and myoclonic epilepsy has been shown with EEG spectral power analysis. Particularly piracetam is involved in restoration of alpha topography in these patients. On the other hand long term effects of piracetam in Alzheimer's disase or minimal cognitive impairment (MCI) patients have not been determined so far. Methods: We have evaluated spectral EEG analysis of 13 minimal cognitive impairment and 18 mild or less severe Alzheimer dementia patients after receiving piracetam 2400 mg and 4800 mg respectively for 4 weeks. Control group was consisted of 16 healthy subjects with similar age and sex characteristics. We analyzed EEG power spectrum before and after delivering 2400 or 4800 mg piracetam. Results: In Alzheimer's disase group enhancement of delta band power began with 2400 mg piracetam and lasted on 4800 mg. Theta band power spectrum values significantly decreased. Alpha and beta band power spectrums were not changed. MCI patients have shown very similar results with AD patients Conclusions: We have found that long term delivering of piracetam enhances slow-wave band powers of EEG both in Alzheimer's disase and MCI patients

Dose estimation and dating of pottery from Turkey

The luminescence method is a widely used technique for environmental dosimetry and dating archaeological, geological materials. In this study, equivalent dose (ED) and annual dose rate (AD) of an archaeological sample were measured. The age of the material was calculated by means of equivalent dose divided by the annual dose rate. The archaeological sample was taken from Antalya, Turkey. Samples were prepared by the fine grain technique and equivalent dose was found using multiple-aliquot-additive-dose (MAAD) and single aliquot regeneration (SAR) techniques. Also the short shine normalization-MAAD and long shine normalization-MAAD were applied and the results of the methods were compared with each other. The optimal preheat temperature was found to be 200. °C for 10. min. The annual doses of concentrations of the major radioactive isotopes were determined using a high-purity germanium detector and a low-level alpha counter. The age of the sample was found to be 510±40 years. © 2012 Elsevier Ltd

Preparation and evaluation of multipurpose herbal mouthwash for oromucosal diseases

2-s2.0-85073387180Due to the many advantages of herbal sources in medication, in this study, it was aimed to prepare and evaluate an herbal mouthwash formulation that can be useful for the treatment of some oromucosal diseases. For this aim, extracts of Thymus vulgaris L. (Lamiaceae), Pelargonium sidoides DC. (Geraniaceae), Glycyrrhiza glabra L. (Leguminosae), Matricaria chamomilla L. (Compositae), Melissa officinalis L. (Lamiaceae) and Laurus nobilis L. (Lauraceae) were used to prepare two different formulations. Physical parameters, pH, density, stability, in vitro antimicrobial activity and in vitro cytotoxicity studies were used for evaluation of formulations. Between the investigated formulations, the formulation that contains extracts of Thymus vulgaris L. (Lamiaceae), Pelargonium sidoides DC. (Geraniaceae), and Glycyrrhiza glabra L. (Leguminosae), showed good antimicrobial activity with acceptable physical characteristics, pH, density, stability and no cytotoxicity on fibroblast cells. It has been promised in order to create an effective and safe herbal oral mouthwash having multipurpose use for oromucosal diseases and further studies will be planned in terms of long-term stability and clinical studies. © 2019, Colegio de Farmaceuticos de la Provincia de Buenos Aires. All rights reserved

Flurbiprofen embedded dipeptide hydrogels coated Ti-6Al-4V implant for drug delivery application

2-s2.0-85073351814In this study, it was aimed to prepare and evaluate drug-releasing dental implant approach by coating the surface of titanium implants with hydroxyapatite and low molecular weight peptide based N-fluorenylmethoxycarbonyl diphenylalanine hydrogel containing flurbiprofen. The effect of polymers on flurbiprofen release was investigated, the cytotoxic effect by using the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) method and the antibacterial activity by using agar diffusion and ASTM 2180-07(2012) Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent(s) In Polymeric or Hydrophobic Materials methods were investigated. Results showed that, flurbiprofen release was up to 60% at the end of 4 h and completed at the end of 11 h for chosen formulation accompanied with no cytotoxic effect that could be accepted for therapeutic aspects. Investigated formulations were fitted to Korsmeyer-Peppas kinetic model with diffusion/relaxation coupled release mechanism. Antibacterial efficacy of implants showed that the number of colonies decreased gradually at each contact time, resulting an antibacterial rate over 99% at the end of 24 h. It can be concluded, an anti-inflammatory drug releasing dental implant having no cytotoxicity and presented antibacterial effect can be successfully prepared. © 2019, Colegio de Farmaceuticos de la Provincia de Buenos Aires. All rights reserved

Indirect dating of an olive tree planting event using luminescence of the sediments lying beneath the roots of the tree: a pilot study in the south-western part of Anatolia, Turkey

The aim of the present study is to attempt assessing the age of a monumental olive tree located between the Antique Cities of Militus (Didim-Aydın region) and Iasos (Milas-Muğla region). Wood from the trunk of an olive tree is not appropriate for conventional dating approaches such as dendrochronology or 14C. The sediments closely located surrounding and beneath the roots of the olive tree are considered indicative of the age of the planting event; therefore these sediments were dated using both quartz and feldspar luminescence signal protocols. Methodological aspects including the preheating plateaus, equivalent dose statistical approaches and dose rate using gamma spectrometry are also discussed, as dating of the associated palaeochannel sediments of the area are presented for the first time in the dating literature. The optically stimulated luminescence and/or infrared stimulated luminescence ages are extrapolated to date the event of the tree planting; it is the first time in the literature that an age is reported for an olive tree in the eastern Mediterranean region. The present study stands as the first experimental evidence that olive trees have been cultivated in the area since the Iron Age. © 2020 John Wiley & Sons, Ltd

Evaluation of thermoluminescence trapping parameters in Li2B4O7 co-doped with Ag+ and Gd3+ using various experimental techniques

The aim of this study is to determine the thermoluminescence (TL) kinetic parameters, including the activation energy (E), frequency factor (s) and order of kinetics (b), for the traps of silver and gadolinium co-doped lithium tetraborate (Li2B4O7:Ag,Gd) phosphor. Four different experimental techniques were applied, including Fractional Glow Technique (FGT), Computerized Glow Curve Deconvolution (CGCD), as well as both Isothermal TL (ITL) and Optically Stimulated Luminescence (OSL) measurements at various stimulation temperatures. The TL glow curve of the phosphor was determined to be composed of two single peaks with delocalization temperatures around 80 °C and 360 °C with a heating rate of 2 °C/s after 10 Gy beta dose. Moreover, a composite TL signal is observed within the temperature region between 110 °C and 320 °C. Both the deconvolution analysis as well as the FGT partially indicates that this composite signal consists of two overlapping TL glow peaks along with a satellite TL peak of suppressed intensity. The reusability of the phosphor was studied up to 20 experimental cycles using beta dose values of 0.5, 5 and 10 Gy to support the FGT procedure. The plot of activation energy vs measured temperature yielded a smooth continuum, with the presence of three not so prominent plateau regions. On the contrary, the CGCD analysis indicated the presence of five TL peaks with increasing activation energy values ranging between 0.63 and 1.56 eV. The ITL results indicate that for the constituents of the composite TL signal within 110 °C and 320 °C, the activation energy is less than 0.5 eV, while the corresponding OSL results of the same signal indicate an activation energy value of 0.83 eV. Based on the results of the present study, (a) the continuum shape of the E vs Tfin plot of the FGT analysis and (b) the behavior of the normalized ITL decay curves provide adequate arguments for the existence of a tunneling recombination pathway in the phosphor. The argumentation is also supported by recent related literature. © 2019 Elsevier B.V.Firat University Scientific Research Projects Management Unit: FDK-2017-6833This research was supported by the Cukurova University Rectorate , Scientific Research Projects Coordination Unit under contract numbers FDK-2017-6833 . The authors gratefully acknowledge this support