32 research outputs found
Novel Hybrid Scaffolds for the Cultivation of Osteoblast Cells
No full textTurkoglu Sasmazel, Hilal/0000-0002-0254-4541In this study, natural biodegradable polysaccharide, chitosan, and synthetic biodegradable polymer, poly(epsilon-caprolactone) (PCL) were used to prepare 3D, hybrid polymeric tissue scaffolds (PCL/chitosan blend and PCL/chitosan/PCL layer by layer scaffolds) by using the electrospinning technique. The hybrid scaffolds were developed through HA addition to accelerate osteoblast cell growth. Characteristic examinations of the scaffolds were performed by micrometer, SEM, contact angle measurement system, ATR-FTIR, tensile machine and swelling experiments. The thickness of all electrospun scaffolds was determined in the range of 0.010 +/- 0.001-0.012 +/- 0.002 mm. In order to optimize electrospinning processes, suitable bead-free and uniform scaffolds were selected by using SEM images. Blending of PCL with chitosan resulted in better hydrophilicity for the PCL/chitosan scaffolds. The characteristic peaks of PCL and chitosan in the blend and layer by layer nanofibers were observed. The PCL/chitosan/PCL layer by layer structure had higher elastic modulus and tensile strength values than both individual PCL and chitosan structures. The layer by layer scaffolds exhibited the PBS absorption values of 184.2; 197.2% which were higher than those of PCL scaffolds but lower than those of PCL/chitosan blend scaffolds. SaOs-2 osteosarcoma cell culture studies showed that the highest ALP activities belonged to novel PCL/chitosan/PCL layer by layer scaffolds meaning better cell differentiation on the surfaces. (C) 2011 Elsevier B.V. All rights reserved.Turkish Academy of Science (TUBA) L'Oreal; L'OrealThe author is greatly thankful to Turkish Academy of Science (TUBA) & L'Oreal for honoring this study with the award "Young Women in Science" in Materials Science in 2009. Her special thanks also go to L'Oreal for the precious financial support. The author also appreciates the invaluable contribution of AWAC (Academic Writing Advisory Center) to this study in linguistic terms
Turkish truffles I: 18 new records for Turkey
No full textWOS: 000352486200014We report the first records of 18 truffle species in Turkey. Three belong to the Ascomycota: Elaphomyces leucocarpus, E. muricatus, and Genea sphaerica; and 15 to the Basidiomycota: Alpova corsicus, Gautieria otthii, G. retirugosa, G. trabutii, Hymenogaster citrinus, H. hessei, H. luteus, H. lycoperdineus, Hysterangium clathroides, H. epiroticum, H. fragile, H. nephriticum, Leucogaster tozzianus, Octaviania asterosperma, and Protoglossum aromaticum. We also report new localities within Turkey for Picoa juniperi, P. lefebvrei, Geopora cooperi, Terfezia arenaria, T. claveryi, Tuber aestivum, and T. nitidum in the Ascomycota; and Leucogaster nudus, Hymenogaster thwaitesii, H. vulgaris, and Melanogaster broomeanus in the Basidiomycota.Scientific and Technological Research Council of Turkey projectTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [T-BAG-111T530, BIDEB-2221]The first author received funding from the Scientific and Technological Research Council of Turkey project number T-BAG-111T530 and BIDEB-2221. We appreciate the help from Abdulkadir Simsek, Ahmet Oksuzoglu, Cemhan Bucak, Coskun Bilgi, Duran Celik, Ekrem Toprak, Esra Er, Fatih Kaya, Gulsum Turkoglu, Idris Sener, Kadir Bazlica, Kadir Ceryan, Mehmet Halil Solak, Mehmet Metin, Mehmet Yucel, Murat Kilic, Mustafa Demir, Mustafa Turuncoglu, Niyazi Ulucoban, Okan Kursun, Osman Coban, Serkan Sevinc, Seyit Ahmet Akay, Tolga Keser, Ugur Demirbilek, Veysel Kodalak, and Yavuzalp Turkoglu in the collection of some of the specimens
Synthesis and characterization of gamma-Bi2O3 based solid electrolyte doped with Nb2O5
No full textgamma-phase bismuth oxide is a well known high oxygen ion conductor and can be used as an electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs). This study aims to determine new phases of Bi2O3-Nb2O5 binary system and the temperature dependence of the electrical transport properties. The reaction products obtained in open air atmosphere were characterized by X-ray powder diffractions (XRD). The unit cell parameters were defined from the indexes of the powder diffraction patterns. The gamma-Bi2O3 crystal system were obtained by doping 0.01 < mole% Nb2O5 < 0.04 at 750 degrees C for 48 and 96 h. Thermal behaviour and thermal stability of the phases were investigated by thermal analysis techniques. Surface and grain properties of the related phases were determined by SEM analysis. The temperature dependence of the electrical properties of gamma-Bi2O3 solid solution was measured by four-point probe d.c. conductivity method. In the investigated system, the highest value of conductivity was observed for sigma(T)=0.016 ohm(-1) cm(-1) at 650 degrees C on 4 mole% Nb2O5 addition. The electrical conductivity curves of studied materials revealed regular increase with temperature in the form of the Arrhenius type conductivity behaviour.Scientific and Technical Research Council of Turkey (TUBITAK) [108T377]The authors would like to thank the Scientific and Technical Research Council of Turkey (TUBITAK) for financial help (Grant no. 108T377)
The impact of diabetes on the association between epicardial fat thickness and extent and complexity of coronary artery disease in patients with non-ST elevation myocardial infarction
No full textSynthesis and characterization of gamma-Bi2O3 based solid electrolyte doped with Nb2O5
No full textgamma-phase bismuth oxide is a well known high oxygen ion conductor and can be used as an electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs). This study aims to determine new phases of Bi2O3-Nb2O5 binary system and the temperature dependence of the electrical transport properties. The reaction products obtained in open air atmosphere were characterized by X-ray powder diffractions (XRD). The unit cell parameters were defined from the indexes of the powder diffraction patterns. The gamma-Bi2O3 crystal system were obtained by doping 0.01 < mole% Nb2O5 < 0.04 at 750 degrees C for 48 and 96 h. Thermal behaviour and thermal stability of the phases were investigated by thermal analysis techniques. Surface and grain properties of the related phases were determined by SEM analysis. The temperature dependence of the electrical properties of gamma-Bi2O3 solid solution was measured by four-point probe d.c. conductivity method. In the investigated system, the highest value of conductivity was observed for sigma(T)=0.016 ohm(-1) cm(-1) at 650 degrees C on 4 mole% Nb2O5 addition. The electrical conductivity curves of studied materials revealed regular increase with temperature in the form of the Arrhenius type conductivity behaviour
New records of some Ascomycete truffle fungi from Turkey
No full textWOS: 000329918200020We report the first records of 6 Ascomycete truffle taxa in Turkey: Genea verrucosa Vittad., Genea klotzschii Berk. & Broome, Stephensia bombycina (Vittad.) Tul. & C. Tul., Terfezia olbiensis Tul. & C. Tul., Tuber excavatum Vittad., and Tuber rufum Pico. We also report new localities within Turkey for Picoa juniperi Vittad., Terfezia leptoderma Tul. & C. Tul., Choiromyces meandriformis Vittad., Tuber brumale Vittad., Tuber nitidum Vittad., and Tuber mesentericum Vittad.Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [T-BAG-111T530]The first author received funding from the Scientific and Technological Research Council of Turkey (project number T-BAG-111T530). We appreciate the help of Niyazi Ulucoban, Serkan Sevinc, Mustafa Turuncoglu, Nihat Guldas, Fatih Kaya, Osman Coban, and Mehmet Cirit in the collection of some of the specimens. We also appreciate the helpful commentary of Dr James M Trappe
Assessing Rock Mass Permeability Using Discontinuity Properties
No full textISRM European Rock Mechanics Symposium (EUROCK) - JUN 20-22, 2017 - Ostrava, CZECH REPUBLICWOS: 000416996000082Field measurement of rock mass permeability is essential that numerous factors influence its directional magnitude. Lugeon test is a popularly conducted field instrument in order to measure hydraulic conductivity of a rock mass. Discontinuity orientation, spacing and discontinuity surface quality, infill presence and type play essential role in permeability of the rock mass in addition to rock material itself. Geological Strength Index (GSI) is a parameter used in Gen. Hoek-Brown failure criterion and supporting empirical equations in order to estimate rock mass strength and deformability parameters. Frequently used Rock Quality Designation (RQD) and GSI and Lugeon values were combined in order to generate a relation among them. The proposed relationships are produced by interpretation of geotechnical core logging and Lugeon test results. (C) 2017 The Authors. Published by Elsevier Ltd.Int Soc Rock Mech, ASCR, Inst GeonPolyak Eynez Energy Mining A.S. and Fina EnergyThe author thanks to Polyak Eynez Energy Mining A.S. and Fina Energy and its personnel for supporting scientific research and providing necessary data for the study. The author presents his gratitudes to Geological Engineers of Polyak Eynez, Feridun Emre Yagimli, Turkoglu, Mehmet Kilic for providing extensive data on the geology of the area, preparation of geotechnical borehole logs and their additional care during hydraulic testing. Special thanks also go to the reviewers
Some fixed point results in complete generalized metric spaces
No full textThe Banach contraction principle is the most important result. This principle has many applications and some authors was interested in this principle in various metric spaces as Brianciari.
The author initiated the notion of the generalized metric space as a generalization of a metric space by replacing the triangle inequality by a more general inequality, for all pairwise distinct points of . As such, any metric space is a generalized metric space but the converse is not true. He proved the Banach fixed point theorem in such a space. Some authors proved different types of fixed point theorems by extending the Banach's result. Wardowski introduced a new contraction, which generalizes the Banach contraction. He using a mapping introduced a new type of contraction called -contraction and proved a new fixed point theorem concerning -contraction. In this paper, we have dealt with -contraction and -weak contraction in complete generalized metric spaces. We prove some results for -contraction and -weak contraction and we show that the existence and uniqueness of fixed point for satisfying -contraction and -weak contraction in complete generalized metric spaces. Some examples are supplied in order to support the useability of our results. The obtained result is an extension and a generalization of many existing results in the literature
Formwork Systems Selection Criteria for Building Construction Projects: A Critical Review of the Literature
No full textFormwork system (FWS) is one of the key components in reinforced concrete (RC) construction. Therefore, selection of the most appropriate FWS plays a critical role in the project success. Since the FWS selection is affected by several compromising and conflicting criteria, numerous studies have been carried out to identify the FWS selection criteria and/or have employed various multi-criteria decision-making (MCDM) methods since the early 1990s. However, there is no research that conducts a critical review of the previous studies addressing the FWS selection criteria in building construction projects. This study aims to fill this knowledge gap. For this purpose, a critical review of the relevant literature was carried out using an integrative approach and the findings were validated through face-to-face interviews with professionals specialized in formwork engineering. The findings of this study may provide practitioners with a useful guide that can assist them in selecting the most appropriate FWS.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Neutrophil to Lymphocyte Ratio Predicts Left Ventricular Remodeling in Patients with ST Elevation Myocardial Infarction after Primary Percutaneous Coronary Intervention
No full textBackground and Objectives: It has been demonstrated that the neutrophil/lymphocyte ratio (NLR) might be a useful marker to predict cardiovascular risk and events. We aimed to investigate the role of the NLR to predict ventricular remodeling (VR) in patients with anterior ST-elevation myocardial infarction (STEMI) who were treated with primary percutaneous coronary intervention. Subjects and Methods: We prospectively included 274 consecutive anterior STEMI patients. Echocardiography was performed during admission and at six months after myocardial infarction. VR was defined as at least 200/0 increase from baseline in left ventricular end diastolic volume. Patients were divided into two groups according to their VR status: VR (n=67) and non-VR (n=207). Total and differential leukocyte count, N -terminal pro -brain natriuretic peptide (NT-proBNP) and other biochemical markers were measured at admission and 24 hours later. Results: Compared with the non-VR group, peak creatine kinase MB (CK-MB), NT-proBNP (24 h), neutrophil/lymphocyte ratio, presence of diabetes, no-reflow frequency and wall motion score index were significantly higher in patients with VR (p<0.05 for all). On multivariate logistic regression analysis, NLR (beta=2.000, 950/o confidence interval=1.577-2.537, p<0.001) as well as peak CK-MB, NT-proBNP (24 h), WMSI and diabetes incidence were associated with VR. The cutoff value of the neutrophil/lymphocyte ratio obtained by receiver operator characteristic curve analysis was 4.25 for the prediction of VR (sensitivity: 79%, specificity: 74%). Conclusion: In patients with anterior STEMI, initial NLR and NT-proBNP measured 24 hours after admission may be useful for predicting adverse cardiovascular events including left VR
