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Primary malignant melanoma

Mısır A.F. | Durmuşlar M.C. | Zerener T. | Gün B.D.

Article | 2016 | Saudi Medical Journal37 ( 4 ) , pp.446 - 449

Malignant melanomas (MM) of the oral cavity are extremely rare, accounting for 0.2% to 8.0% of all malignant melanomas. Malignant melanomas is more frequently seen at the level of the hard palate and gingiva. Early diagnosis and treatment are important for reducing morbidity. Malignant melanoma cells stain positively with antibodies to human melanoma black 45, S-100 protein, and vimentin; therefore, immunohistochemistry can play an important role in evaluating the depth of invasion and the location of metastases. A 76-year-old man developed an oral malignant melanoma, which was originally diagnosed as a bluish reactive denture hyper . . .plasia caused by an ill-fitting lower denture. The tumor was removed surgically, and histopathological examination revealed a nodular-type MM. There was no evidence of recurrence over a 4-year follow-up period. © 2016, Saudi Arabian Armed Forces Hospital. All rights reserved Daha fazlası Daha az

Variation in the radon concentrations and outdoor gamma radiation levels in relation to different geological formations in the thermal regions of Bursa, Turkey

Akkaya G. | Kahraman A. | Koray A. | Kaynak G.

Article | 2016 | Journal of Radiological Protection36 ( 3 ) , pp.490 - 503

Spring waters used as spas and their region may contain significant amounts of natural radionuclides. The main sources of exposure are the inhalation of radon and its decay products released from the water and soil and terrestrial gamma-radiation. In order to evaluate the potential risk of thermal regions in Bursa, located in the impact area of the NAF (North Anatolian Fault), radon and thoron concentrations in soil gas, radon concentrations in thermal waters and outdoor gamma radiation levels were measured in thermal regions that have different geological formations. The radon and thoron concentrations in soil-gas were found to var . . .y from 2272 ± 121 to 245196 ± 3455 Bq m-3 and from 999 ± 218 to 178 848 ± 17 742 Bq m-3, respectively. The radon concentrations in thermal waters ranged from 0.99 ± 0.21 to 226.74 ± 2.51 Bq l-1 in the rainy season and from 0.26 ± 0.10 to 178.03 ± 12.86 Bq l-1 in the dry season. The measured outdoor gamma radiation levels varied from 38 to 180 nGy h-1. The gamma dose rates were found to be strong positively correlating with the radon and thoron concentrations in soil-gas. The radon and outdoor gamma radiation levels were observed to be a function of the geological formations of the area. © 2016 IOP Publishing Ltd Daha fazlası Daha az

Male and female gametophyte development of Seseli resinosum (Apiaceae)

Kaplan A. | Iris H.

Article | 2016 | Journal of Applied Biological Sciences10 ( 3 ) , pp.1 - 8

The male and female gametophyte development in Seseli resinosum Freyn et Sint were studied with alight microscope. Anther wall development follows the dicotyledonous type: epidermis, endothecium, middle layer, and tapetum. The tapetum is secretory andthe tapetal cells are two-, three- and four-nucleate. The microspore tetrads are tetrahedral and isobilateral,and pollen grains are shed during a three cellular stage. The mature ovule is anatropous, tenuinucellar and unitegmic. A funicular obturator is present, and the hypostase is absent. The nucellarepidermis is one layered.Absorption of the nucellus occurs in four-nucleate embryo sa . . .c. A linear megaspore tetrad is formed, and the megaspore on the chalazal side remains active. The functional megaspore produces a seven-celled embryosac corresponding to the Polygonumtype. The embryo sac formation is monosporic Daha fazlası Daha az

Restoration approach to improve sustainability and longevity in existing historical structures

Sayin B. | Akcay C. | Yildizlar B. | Bilir T. | Bozkurt T.S.

Conference Object | 2016 | Sustainable Construction Materials and Technologies2016-August , pp.1 - 8

An aspect of the sustainable structure is the retrofitting of structural members in buildings and this yield to less use of natural resources and increase the strength of such materials for the same or similar purpose, thereby reducing waste as well. Sustainable structure also enhances the recycling of the industry as such materials are readily available in the world market. Structural materials are examples of sustainable materials and its combinations, however, the life time of structures and materials are decreased by environmental conditions, especially. Accordingly, repairing and strengthening of historical structures are an im . . .portant factor in terms of transfer new generations and maintain preserving of such structures. This study focuses on restoration studies included repairing and strengthening, therefore, it is aimed to extend the buildings’ service life and preserve its original structure and materials. In the present study, historical buildings, registered as protection required of cultural asset by the Protection of Cultural Assets District Board, is investigated. It is examined that retrofitting techniques in the buildings are performed repairing and strengthening applications by steel profile, jacketing, lime mortar, CFRP, steel mesh and injection according to material analysis on historical structural members. © 2016 International Committee of the SCMT conferences. All rights reserved Daha fazlası Daha az

Grey system theory supported Markowitz Portfolio Optimization during high volatility periods

Chambers N. | Hamzacebi C. | Fatih Bayramoglu M.

Article | 2016 | Journal of Grey System28 ( 4 ) , pp.79 - 95

Investment in stocks in high volatility periods is more difficult for investors relative to periods with lower volatility. In these high volatility periods, the efficiency levels of markets tend to decrease and the probability investors facing asymmetric information increase. As such, certain modern approaches are needed for not only stock selection, but also for portfolio creating with selected stocks. This study runs a Markowitz Portfolio Optimization supported by Grey Systems Theory on selected stocks from the BIST 30 Index for a time period during the 2008 Global Financial Crisis. The purpose of this study is to develop a model, . . . which can be used for investor decision making in the periods of uncertainty. Additionally, this study also compares the performances of the developed model, Hybrid portfolios and Traditional portfolios. The results of the study show that the developed models with a modern approach can be applicable and successful for periods with high volatility. © 2016, Research Information Ltd. All rights reserved Daha fazlası Daha az

A new approach to rock brittleness and its usability at prediction of drillability

Özfirat M.K. | Yenice H. | Şimşir F. | Yarali O.

Article | 2016 | Journal of African Earth Sciences119 , pp.94 - 101

Rock brittleness is one of the most important issues in rock drilling and cutting. The relations between drillability and brittleness will assist engineers in excavation works. The demand for representative rock parameters related to planning of underground excavations is increasing, as these parameters constitute fundamental input for obtaining the most reliable cost and time estimates. In rock cutting mechanics, the effects of the rock and brittleness on the efficiency of drilling and excavation are examined by many researchers. In this study, 41 different rock types were tested in laboratory to investigate the relations between t . . .he drilling rate index and different brittleness values. Firstly, the relations defined in literature are tested. Strength tests are made according to International Society for Rock Mechanics standards. In addition Norwegian University of Science and Technology standards are used to determine drilling rate index. Then, a new brittleness index is proposed which is the arithmetic average of uniaxial compressive strength and tensile strength. Considering the regression analysis carried out, it was seen that the proposed formula showed good correlation for these samples handled in this study. As a result of this study, a high correlation is obtained between the proposed index and drilling rate index values (R:0.84). The results are found to be at least reliable as well as other brittleness equations given in literature. © 2016 Elsevier Ltd Daha fazlası Daha az

Rotation mixing-assisted liquid-liquid microextraction: A new microextraction approach for the determination of priority phenols in water samples

Çabuk H. | Ata Ş.

Article | 2016 | Analytical Methods8 ( 15 ) , pp.3123 - 3131

In this study, a new sample pretreatment method termed as rotation mixing-assisted liquid-liquid microextraction combined with liquid chromatography with ultraviolet detection was developed for the determination of selected priority phenols in water samples. In this approach, a binary solvent system of water sample and low-density extraction solvent (1-dodecanol) was mixed at 80 rpm for 8 min with a circular rotation in the absence of a disperser solvent. Fine organic droplets were formed during continuous end-over-end action, which accelerated mass transfer of the analytes to the organic phase. After extraction, phase separation wa . . .s performed by centrifugation and the enriched analytes in the floated extractant phase were determined. A series of parameters that influence extraction were investigated systematically. Under the optimized conditions, the enrichment factors and extraction recoveries ranged from 61 to 138 and 37 to 83%, respectively, that were comparable with those obtained by other mechanical methodologies, i.e., vortex agitation, magnetic stirring and ultrasonic treatment. The limits of detection were 0.29-0.63 ng mL-1. Relative standard deviations were less than 5.3% for intra-day and 8.3% for inter-day precision. This method has been also successfully applied to analyze real water samples at two different spiked concentrations and satisfactory recoveries were achieved. © The Royal Society of Chemistry 2016 Daha fazlası Daha az

Wigner-Ville distribution based ECG arrhythmia detection for telemedicine applications [Tele-Tip Uygulamalari için Wigner-Ville Dagilim Esasli EKG Aritmi Belirleme]

Kayikcioglu I. | Akdeniz F. | Kayikcioglu T.

Conference Object | 2016 | 2016 24th Signal Processing and Communication Application Conference, SIU 2016 - Proceedings , pp.2045 - 2048

While the world's population is growing, average life expectancy is increasing. As a result, the growing elderly population is profoundly affecting the delivery of healthcare for everyone and in particular for those with chronic diseases. The remote monitoring of chronic patients may be achieved by a telemedicine system utilizing today's information and mobile communication technologies. In this study, an ECG arrhythmia detection algorithm based on Wigner-Ville distribution is developed. The performance of the method is tested on data obtained from the PhysioNet database. © 2016 IEEE.

Analysis of Turkish prospective science teachers' perceptions on technology in education

Yaman S. | Koksal M.S. | Saka Y.

Article | 2016 | Australian Journal of Teacher Education41 ( 1 ) , pp.22 - 41

Purpose of this study was to determine and analyze Turkish pre-service science teachers' perceptions on technology in terms of learning style, computer competency level, possession of a computer, and gender. The study involved 264 Turkish pre-service science teachers. Analyses were conducted through four-way ANOVA, t-tests, Mann Whitney U test and one-way ANOVAs and the results showed there were one main effect for gender and one interaction effect between gender and computer competency level. The interaction effect pointed out that the male pre-service science teachers who were weak in computer competency held more positive percept . . .ions toward instructional technology than their counterparts Daha fazlası Daha az

Postglacial floodings of the Marmara Sea: molluscs and sediments tell the story

Büyükmeriç Y.

Article | 2016 | Geo-Marine Letters36 ( 4 ) , pp.307 - 321

The early Holocene marine flooding of the Black Sea has been the subject of intense scientific debate since the “Noah’s Flood” hypothesis was proposed in the late 1990s. The chronology of the flooding is not straightforward because the connection between the Black Sea and the Mediterranean Sea involves the intermediate Marmara Sea Basin via two sills (Dardanelles and Bosphorus). This study explores the chronology of late Pleistocene–Holocene flooding by examining sedimentary facies and molluscs from 24 gravity cores spanning shelf to slope settings in the southern Marmara Sea Basin. A late Pleistocene Ponto-Caspian (Neoeuxinian) mol . . .lusc association is found in 12 of the cores, comprising 14 mollusc species and dominated by brackish (oligohaline–lower mesohaline) endemic taxa (dreissenids, hydrobiids). The Neoeuxinian association is replaced by a Turritella–Corbula association at the onset of the Holocene. The latter is dominated by marine species, several of which are known to thrive under dysoxic conditions in muddy bottoms. This association is common in early Holocene intervals as well as sapropel intervals in younger Holocene strata. It is an indicator of low-salinity outflows from the Black Sea into the Marmara Sea that drive stratification. A marine Mediterranean association (87 species) represents both soft bottom and hard substrate faunas that lived in well-ventilated conditions and upper mesohaline–polyhaline salinities (ca. 25 psu). Shallower areas were occupied by hard substrate taxa and phytopdetritic communities, whereas deeper areas had soft bottom faunas. The middle shelf part of the northern Gemlik Gulf has intervals with irregular and discontinuous sedimentary structures admixed with worn Neoeuxinian and euryhaline Mediterranean faunas. These intervals represent reworking events (slumping) likely related to seismic activity rooted in the North Anatolian Fault system. The core data and faunas indicate an oscillating postglacial sea-level rise and phases of increased/decreased ventilation in the Marmara Sea during the Holocene, as well as palaeobiogeographic reorganisations of Ponto-Caspian and Mediterranean water bodies since the latest Pleistocene Daha fazlası Daha az

Investigation of the production of 68Ga using pre-equilibrium models

Baldik R. | Dombayci A.

Article | 2016 | Applied Radiation and Isotopes113 , pp.10 - 17

In this study, some nuclear reactions for the production of 68Ga radioisotope are investigated using pre-equilibrium nuclear reaction models. For this aim, by the pre-equilibrium reaction mechanisms, the excitation functions and emission spectra of some nuclear reactions for the production of 68Ga radioisotope are calculated. These calculations are performed in the ALICE/ASH and the TALYS 1.6 codes. The obtained results have been discussed and compared with the available experimental results. © 2016 Elsevier Ltd.

Effect of sealant agents on the color stability and surface roughness of nanohybrid composite resins

Dede D.Ö. | Şahin O. | Koroglu A. | Yilmaz B.

Article | 2016 | Journal of Prosthetic Dentistry116 ( 1 ) , pp.119 - 128

Statement of problem The effect of sealant agents on the surface roughness and color stability of nanohybrid composite resins is unknown. Purpose The purpose of this in vitro study was to evaluate the effect of sealant agents on the surface roughness and color stability of 4 nanohybrid composite resin materials. Material and methods Forty disks (10×2 mm) were fabricated for each nanohybrid composite resin material (Z-550, Tetric EvoCeram, Clearfill Majesty, Ice) (N=160) and divided into 4 surface treatment groups: 1 conventional polishing (control) and 3 different sealant agent (Palaseal, Optiglaze, BisCover) coupling groups (n=10). . . . The specimens were thermocycled, and surface roughness (R a ) values were obtained with a profilometer. Scanning electron microscope images were also recorded. CIELab color parameters of each specimen were measured with a spectrophotometer before and after 7 days of storage in a coffee solution. Color differences were calculated by the CIEDE 2000 (?E 00 ) formula. The data were statistically analyzed by 2-way ANOVA and by the Tukey HSD test (?=.05). Results The surface treatment technique significantly affected the R a values of the composite resins tested (P<.001). The interaction between the surface treatment technique and composite resin material was also significant for ?E 00 values (P<.05). Within the composite resin groups, significant decreases in R a were observed only for the Palaseal agent coupled composite resin groups (except Ice) compared with the control groups (P<.05). Scanning electron microscope images revealed rougher surfaces with conventionally polished groups compared with test groups. Conventionally polished groups had the highest ?E 00 (3.09 to 3.49) values for each composite resin group, except for BisCover applied Clearfill Majesty (P<.05). Within the composite resin groups, significant differences were observed between the color change seen with BisCover and other sealants for Clearfill Majesty composite resin (P<.05). Conclusions Using Palaseal agent on all tested composite resins except for Ice produced smoother surfaces. All surface sealant agents provided less discoloration of nanohybrid composite resins after coffee staining compared with conventional polishing except for BisCover applied Clearfill Majesty composite resin. © 2016 Editorial Council for the Journal of Prosthetic Dentistr Daha fazlası Daha az

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