Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Demir, Selim(9)
- Turan, Ibrahim(7)
- Aliyazicioglu, Yuksel(6)
- Bostan, Sedat(6)
- Demir, Sertaç Timur(6)
- Mentese, Ahmet(5)
- Aliyazicioglu, Rezzan(4)
- Ashyralyyev, Charyyar(4)
- Dokuz, Abdurrahman(4)
- Simsek, Cemaleddin(4)
- Sipahi, Ferkan(4)
- Somuncuoğlu, Seda Özsoy(4)
- Vural, Alaaddin(4)
- Yaman, Serap Ozer(4)
- Öztürk, S.(4)
- Adanur, S.(3)
- Akpinar, Ozlem(3)
- Aksakal, Vecihi(3)
- Albayrak, Cenk(3)
- Cengiz, Selim(3)
- Deger, Orhan(3)
- Eker, Çiğdem Saydam(3)
- Gümrük, Recep(3)
- Güzel, Melıh(3)
- Kandemir, Raif(3)
- Karahan, Selim(3)
- Karsli, Orhan(3)
- Kayhan, Mustafa(3)
- Kilinc, Kagan(3)
- Kiremitçi, Ferdi(3)
- Korucuk, Selçuk(3)
- Küçük, Murat(3)
- Kılıç, Taşkın(3)
- Maden, N.(3)
- Misir, Sema(3)
- Peker, Osman(3)
- Sirat, Abdulveli(3)
- Sukuroglu, Ebru Emine(3)
- Tatli, Yasemin(3)
- Tosunoğlu, Büşra(3)
Yayınlar
- MakaleYalnız künye2017Genome reprogramming in Saccharomyces cerevisiae upon nonylphenol exposure
Bereketoglu, Ceyhun; Arga, Kazim Yalcin; Eraslan, Serpil; Mertoglu, Bulent
Bioaccumulative environmental estrogen, nonylphenol (NP; 4-nonylphenol), is widely used as a nonionic surfactant and can affect human health. Since genomes of Saccharomyces cerevisiae and higher eukaryotes share many structural and functional similarities, we investigated subcellular effects of NP on S. cerevisiae BY4742 cells by analyzing genome-wide transcriptional profiles. We examined effects of low (1 mg/l; <15% cell number reduction) and high (5 mg/l; >65% cell number reduction) inhibitory concentration exposures for 120 or 180 min. After 120 and 180 min of 1 mg/l NP exposure, 187 (63 downregulated, 124 upregulated) and 103 genes (56 downregulated, 47 upregulated), respectively, were differentially expressed. Similarly, 678 (168 repressed, 510 induced) and 688 genes (215 repressed, 473 induced) were differentially expressed in cells exposed to 5 mg/l NP for 120 and 180 min, respectively. Only 15 downregulated and 63 upregulated genes were common between low and high NP inhibitory concentration exposure for 120 min, whereas 16 downregulated and 31 upregulated genes were common after the 180-min exposure. Several processes/pathways were prominently affected by either low or high inhibitory concentration exposure, while certain processes were affected by both inhibitory concentrations, including ion transport, response to chemicals, transmembrane transport, cellular amino acids, and carbohydrate metabolism. While minimal expression changes were observed with low inhibitory concentration exposure, 5 mg/l NP treatment induced substantial expression changes in genes involved in oxidative phosphorylation, cell wall biogenesis, ribosomal biogenesis, and RNA processing, and encoding heat shock proteins and ubiquitin-conjugating enzymes. Collectively, these results provide considerable information on effects of NP at the molecular level.
- MakaleAçık Erişim2017Developing web based decision support system for evaluation occupational risks at shipyards
Cebi, Selcuk; Akyuz, Emre; Sahin, Yasin
In this study, a web based decision support system (WBDSS) has been developed to provide decision aid for risk analysis on occupational health and safety at shipyards. The system has been constructed as a modular structure to make its application easy for all kind of firms. The WBDSS is rule based and its database includes safety measures and risks for each tool and machine used in shipbuilding process. In addition, probability and hazard values have been involved in the case of violated measures. The frequencies of the violations that occurred in the work environment are entered to the system by the user. Hence, the system provides a decision support about the risks related to facilities and the cautions to be taken in the workplace. The developed WBDSS has the capability of determining accident, almost accident, and threat formation factors at workplace according to the changing parameters. In this aspect, it enables one to constantly monitor, check and evaluate risk preventive measures. Then, the capabilities of the suggested decision support system have been tested with different scenarios for shipyard processes. When the developed WBDSS is applied to all workplaces, it is aimed at providing a decrease in the number of accidents which cause death, occupational illness, injury, and temporary incapability.
- MakaleYalnız künye2017Comparison of low cost 3D structured light scanners for face modeling
Bakirman, Tolga; Gumusay, Mustafa Umit; Reis, Hatice Catal; Selbesoglu, Mahmut Oguz; Yosmaoglu, Serra; Yaras, Mehmet Cem; Seker, Dursun Zafer; Bayram, Bulent
This study aims to compare three different structured light scanner systems to generate accurate 3D human face models. Among these systems, the most dense and expensive one was denoted as the reference and the other two that were low cost and low resolution were compared according to the reference system. One female face and one male face were scanned with three light scanner systems. Point-cloud filtering, mesh generation, and hole-filling steps were carried out using a trial version of commercial software; moreover, the data evaluation process was realized using CloudCompare open-source software. Various filtering and mesh smoothing levels were applied on reference data to compare with other low-cost systems. Thus, the optimum reduction level of reference data was evaluated to continue further processes. The outcome of the presented study shows that low-cost structured light scanners have a great potential for 3D object modeling, including the human face. A considerable cheap structured light system has been used due to its capacity to obtain spatial and morphological information in the case study of 3D human face modeling. This study also discusses the benefits and accuracy of low-cost structured light systems.
- MakaleYalnız künye2017Geochemical and isotopic characteristics of stream and terrace sediments of the harsit stream, NE Turkey
Eker, Çiğdem Saydam
The current study compares and contrasts the elemental concentrations and the Nd, Sr and O isotopic compositions of sediments collected from the Harsit Stream bed sediments (HSBS) and terrace sediments (HSTS). There are positive correlations between Al2O3 and SiO2, TiO2, Na2O and Fe2O3, K2O in HSBS and between Al2O3 and Fe2O3, MnO in the HSTS samples. Major element components of HSBS and HSTS are comparable to average upper continental crust. Both types of sediments are generally classified as greywacke, based on chemical composition and O–Sr isotopic compositions. TheɛNd(0) andɛSr(0) values range from −0.6 to −5.7 and from 7.1 to 45, respectively, in HSBS; and from −0.7 to −4.4 and from 20 to 54, respectively, in HSTS. The δ18O values range from 8.8 to 11.8 (average 10.8) in HSBS and from 11.3 to 13.3 (average 12.2) in HSTS, which are generally controlled by detrital or authigenic minerals in the studied samples. The average chemical index of alteration (CIA) and, plagioclase index of alteration (PIA) values are high in HSTS, whereas the index of compositional variability (ICV) and weathering index (WIP) values are high in HSBS. Several minor differences were observed between HSBS and HSTS in terms of geochemistry and isotopic compositions that reflect different processes involved in their sedimentation.
- MakaleYalnız künye2017Stereo-based palmprint recognition in various 3D postures
Bingöl, Özkan; Ekinci, Murat
In order to increase performance in palmprint recognition systems, various devices are normally used to restrict the movement of the hand. These can cause problems, especially for those users with physical disabilities. They also cause significant hygiene problems in multi-user systems. Recently, studies on palmprint recognition systems have progressed towards the development of unconstrained, contactless and unrestricted background techniques. The most common problem encountered in these studies is the alignment arising from the free movement of the hand. Despite 3D hand-acquisition devices which offer extra recognition features to overcome this problem, the applicability of these devices is low because of their increased cost. In this study, a stereo camera was proposed. Although due to matching problems, it is difficult to achieve precise, distinct feature extraction in the unrestricted 3D environment used for palmprint recognition, the orientation of the hand in 3D space can be determined by obtaining depth information. In this study, the depth information was extracted by using the binocular stereo approach. First, the orientation of the hand was estimated by fitting a surface model associated with the eigenvectors of the depth information. Pose correction was then accomplished by establishing a relationship between the orientation and the images. The pose correction greatly relieved the perspective distortion that usually occurs within the various poses of the hands. Next, the region of interest was determined by performing segmentation on the corrected images using the Active Appearance Model (AAM). The palmprint features were then extracted via Gabor-based Kernel Fisher Discriminant Analysis. In order to demonstrate the performance of the proposed approach, a new dataset was compiled from stereo images within various scenarios collected from 138 different individuals. As a result of these experimental studies, the EER values, especially on the images captured from different hand orientations in 3D, were reduced from around 14–0.75%. With the help of this suggested approach, the palmprint recognition system was transformed into a more portable form by removing the closed-box mechanisms and equipment restricting movement of the hand. This system can automatically perform pose estimation, hand segmentation and recognition processes without any special intervention.
- MakaleAçık Erişim2017ZnO and ZnO1−x based thin film memristors: The effects of oxygen deficiency and thickness in resistive switching behavior
Gul, Fatih; Efeoglu, Hasan
In this study, direct-current reactive sputtered ZnO and ZnO1−x based thin film (30 nm and 300 nm in thickness) memristor devices were produced and the effects of oxygen vacancies and thickness on the memristive characteristics were investigated. The oxygen deficiency of the ZnO1−x structure was confirmed by SIMS analyses. The memristive characteristics of both the ZnO and ZnO1−x devices were determined by time dependent current–voltage (I-V-t) measurements. The distinctive pinched hysteresis I-V loops of memristors were observed in all the fabricated devices. The typical homogeneous interface and filamentary types of memristive behaviors were compared. In addition, conduction mechanisms, on/off ratios and the compliance current were analyzed. The 30 nm ZnO based devices with native oxygen vacancies showed the best on/off ratio. All of the devices exhibited dominant Schottky emissions and weaker Poole-Frenkel conduction mechanisms. Results suggested that the oxygen deficiency was responsible for the Schottky emission mechanism. Moreover, the compliance currents of the devices were related to the decreasing power consumption as the oxygen vacancies increased.
- BildiriAçık Erişim2017K-Ar dating for determining the age of mineralization as alteration product: A case study of antimony mineralization vein type in granitic rocks of Gümüşhane area, Turkey
Vural, A.
Is it feasible to use K-Ar dating method in determination of the age of mineralization by utilizing alteration minerals? The purpose of this study was to examine the utility of the K-Ar dating method to accurately determine the age of mineralization. In ideal circumstances, dating of alteration products, such as illite and serisite minerals, gives the age of alteration event, which is indirectly associated with mineralization. In the study site, referred to as Avliyana, antimony mineralization (Gümüşhane, Turkey), stibnite (antimony) mineralizations of hydrothermal vein type were observed in granitic young intrusive rocks and the host rocks. In the study area, alteration was observed in the form of a small amount of weak silicification, argillitization (sericitization and illitization), hematitization, limonitization close to the mineralization and of epidotization and chloritization far from the mineralization. In order to determine the limits of the age of antimony mineralizations of the area, the K-Ar method was used to date illite and serisite minerals, which are alteration products related to mineralization. Two samples containing sericite and illite were collected from Avliyana antimonite mineralization. The alteration origin of these minerals was confirmed by supporting petrographic, XRD and scanning electron microscope studies. These samples were analysed for K-Ar dating.
- MakaleAçık Erişim2017Excited Muon Searches at the FCC-Based Muon-Hadron Colliders
Caliskan, A.; Kara, S.O.; Ozansoy, A.
We study the excited muon production at the FCC-based muon-hadron colliders. We give the excited muon decay widths and production cross-sections. We deal with the μp→μ∗q→μγq process and plot the transverse momentum and normalized pseudorapidity distributions of final state particles to define the kinematical cuts best suited for discovery. By using these cuts, we get the mass limits for excited muons. It is shown that the discovery limits obtained on the mass of μ∗ are 2.2, 5.8, and 7.5 TeV for muon energies of 63, 750, and 1500 GeV, respectively.
- MakaleAçık Erişim2017Effect of brewing conditions on antioxidant properties of rosehip tea beverage: study by response surface methodology
İlyasoğlu, Huri; Arpa, Tuba Eda
The aim of this study was to investigate the effects of brewing conditions (infusion time and temperature) on the antioxidant properties of rosehip tea beverage. The ascorbic acid content, total phenolic content (TPC), and ferric reducing antioxidant power (FRAP) of rosehip tea beverage were analysed. A two-factor and three-level central composite design was applied to evaluate the effects of the variables on the responses. The best quadratic models were obtained for all responses. The generated models were validated under the optimal conditions. At the optimal conditions, the rosehip tea beverage had 3.15 mg 100 mL−1 of ascorbic acid, 61.44 mg 100 mL−1 of TPC, and 2591 µmol of FRAP. The best brewing conditions for the rosehip tea beverage were found to be an infusion time of 6–8 min at temperatures of 84–86 °C.
- MakaleAçık Erişim2017The effect of sintering in different atmospheres on superconductivity parameters of YBCO
Başoǧlu, Mehmet
YBa2Cu3O7 (Y123) is a superconductor material discovered in 1987 and its transition temperature is above the liquid nitrogen temperature. It is known that superconductor samples produced by the solid-state reaction route are very often sintered in air atmosphere. However, in the presented work, Y123 was prepared by the same technique using a sintering ambient composed of a mixture of oxygen and argon gases for the first time. Critical current densities of the samples were calculated using results of magnetization measurements. It was obtained from magnetization analysis that all the samples exhibited superconductor character. It was also observed that the sample sintered in the 50% oxygen and 50% argon atmosphere showed the highest critical current density.
- MakaleAçık Erişim2017A new colorimetric DPPH• scavenging activity method with no need for a spectrophotometer applied on synthetic and natural antioxidants and medicinal herbs
Akar, Zeynep; Küçük, Murat; Doğan, Hacer
2,2-Diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging, the most commonly used antioxidant method with more than seventeen thousand articles cited, is very practical; however, as with most assays, it has the major disadvantage of dependence on a spectrophotometer. To overcome this drawback, the colorimetric determination of the antioxidant activity using a scanner and freely available Image J software was developed. In this new method, the mixtures of solutions of DPPH• and standard antioxidants or extracts of common medicinal herbs were dropped onto TLC plates, after an incubation period. The spot images were evaluated with Image J software to determine CSC50 values, the sample concentrations providing 50% colour reduction, which were very similar with the SC50 values obtained with spectrophotometric method. The advantages of the new method are the use of lower amounts of reagents and solvents, no need for costly spectrophotometers, and thus significantly lowered costs, and convenient implementation in any environment and situation.
- MakaleYalnız künye2017An injectable alginate-based hydrogel for microfluidic applications
Akay, Seref; Heils, Rene; Trieu, Hoc Khiem; Smirnova, Irina; Yesil-Celiktas, Ozlem
The objective of this study was to develop an injectable alginate based formulation for immobilizing enzymes into microfluidic systems. The gelation was induced upon lowering the pH by addition of D-glucono-δ-lactone (GDL) and release of Ca+ ions from solid CaCO3. The effects of GDL concentration on enzymatic activity and gelation time were investigated. The results indicated that increasing the GDL concentration increased both surface area and enzymatic activity. Also, chitosan was added to the formulation at different ratios to enhance the stability of enzyme during immobilization. For microfluidic application, 100 μl spiral coil single channel microchip was fabricated and alginate GDL mixture containing β-glucosidase was injected to the microchannel prior to gelation. Enzymatic conversion was performed by pumping substrate (pNPG) through the microchannel. The results indicated that the entire substrate was converted continuously during 24 h without any leakage or deactivation of immobilized enzyme.
- MakaleYalnız künye2017An Investigation of the Seismic Behaviour of an Ancient Masonry Bastion Using Non-Destructive and Numerical Methods
Altunisik, A.C.; Adanur, S.; Genc, A.F.; Gunaydin, M.; Okur, F.Y.
Determining the structural behavior of masonry structures is a challenge due to their lack of homogeneity. The seismic behavior of masonry structures is especially complex. The aim of this study was to examine the structural behavior of Zağanos Bastion using both experimental and numerical methods. The Operational Modal Analysis technique, including the Enhanced Frequency Domain Decomposition Method, and the Stochastic Subspace Identification Method were used to illustrate experimentally the dynamic characteristic of the bastion. A finite element model was developed using ANSYS software in order that the dynamic characteristics of the bastion, including natural frequencies and mode shapes, could be calculated numerically. Seismic analysis was carried out using the 1999 Kocaeli earthquake ground motion record to determine the linear and nonlinear seismic behavior of the bastion. The Turkish Earthquake Code and its general technical specifications were used to evaluate the seismic results. The results show that the maximum and minimum principal stresses exerted on the masonry components exceeded the code requirements at some points, but in general the requirements for the stresses were satisfied.
- MakaleAçık Erişim2017Reaction of 9-oxabicyclo[4.2.1]non-7-ene-1-ol with tetrazine: An unusually facile intramolecular rearrangement
Kaya, Afşin A.; Salamci, Emine; Menzek, Abdullah; Erdem, Safiye S.; Şahin, Ertan; Ecer, Kadriye
Reaction of (1S*,7R*)-9-oxabicyclo[4.2.1]non-7-en-1-ol (5) with dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate (6) produced (2R*,4R*)-dimethyl 4-(7-oxooxepan-2-yl)-1,4-dihydropyridazine-3,6-dicarboxylate (11) in a one-pot reaction involving cycloaddition at ambient conditions. The structure of the rearrangement product 11 was determined by X-ray crystallographic analysis. Its formation was discussed based on experimental studies and density functional theory calculations. The driving force of this unusually facile reaction was the stability of the caprolactone product 11 and the extremely exorgenic loss of N2. Structural factors facilitating this rearrangement were also explored employing PCM//M06-2X/6-31G(d, p) calculations.
- MakaleYalnız künye2017An on-line HPLC system for detection of antioxidant compounds in some plant extracts by comparing three different methods
Arslan Burnaz, Nesibe; Küçük, Murat; Akar, Zeynep
Echinacea (Echinacea purpurea), green tea (Camellia sinensis) and yaylacayi (Thymus praecox OPIZ subsp. grossheimii (Ronniger) Jalas) are herbs used in traditional medicine because of their beneficial health effects. A high performance liquid chromatography (HPLC) post-column method was developed by coupling HPLC with on-line antioxidant assays using diode array (DAD) and ultraviolet (UV) detectors. Thus antioxidant compounds and fifteen phenolic standards were detected in echinacea, green tea and yaylacayi methanol extracts simultaneously. Later on, the developed on-line HPLC coupled system was used to compare three different antioxidant methods, ABTS [2,2′-Azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)], DPPH (2,2-diphenyl-1-picrylhydrazyl and FRAP (Ferric reducing antioxidant power). Eight compounds with antioxidant activity were identified as gallic acid, protocatechuic aldehyde, p-OH benzoic acid, chlorogenic acid, caffeic acid, vanillin, ferulic acid, and rosmarinic acid. For validation purposes, LOD (limit of detection) (0.36–14.68 μg/mL) and LOQ (limit of quantification) (1.35–48.92 μg/mL) values were calculated for six standards. The results showed that while the post-column ABTS and FRAP assays were repeatable, sensitive and supportive of each other, the post-column DPPH assay did not provide reliable results. Also due to the base-line noise and drifts in post-column DPPH assay, identification and quantitation of analytes could not be done accurately.
- Kitap BölümüYalnız künye2017Giffen good or giffen behavior
Ipek, Egemen
- BildiriYalnız künye2017THE ROLE OF NATIONAL AND INTERNATIONAL GEOSPATIAL DATA SOURCES IN COASTAL ZONE MANAGEMENT
Bayram, Bulent; Avsar, Ozgur; Seker, Dursun Zafer; Kayi, Abdullah; Erdogan, Mustafa; Eker, Oktay; Janpaule, Inese; Reis, Hatice Catal
Coastline changes are increasing rapidly due to both natural and human effects. The expansion of touristic, industrial and culture fishing establishments through coastal areas has brought about uncontrolled and unplanned urbanization. In this study, the coastline in Karasu district of Turkey has been extracted by using Unmanned Aerial Vehicle (UAV) images. For this purpose; 7 cm ground sample distance (GSD) UAV images taken in 2013 by Gatewing-X100 by 40% side and 70% forward overlap was used as post images. Produced ortho images were used as the base map for extraction of the coastline. An object-oriented approach has been applied to capture the shoreline from these ortho images. In the presented study, the eCognition object-oriented fuzzy image processing software has been used. This commercial software has the ability to develop custom tools for image classification in addition to its standard object feature tools. Customized arithmetic features have been used to achieve more accurate shoreline segmentation results. Three main object classes have been created as sea, shoreline buffer and land to extract shoreline. The segmentation results were converted into dxf vector data format. The results were compared with manual digitizing of 55 blind readers. An algorithm has been developed by using Matlab to analyze the differences between object-oriented classification and manual digitizing results. Results were evaluated according to students' gender, age, spent time, used software and courses taken. The root mean square error (RMSE) was calculated as 7.15 m.
- MakaleAçık Erişim2017Nutmeg Intoxication Associated with Consumption as a Stupefacient
Günaydin, Mucahit; Tatli, Ozgur; Altuntas, Gurkan; Uslu, Zakire; Özsahin, Faruk; Beslioglu, Necla
Introduction: Nutmeg is the dried seed of an evergreen aromatic tree from the plant family Myristicaceae. It is widely used in traditional medicine. Although misuse is rare, it needs to be understood that this plant, widely used as a spice in various parts of the world, can be misused and can result in emergency presentation due to intoxication. Case Report: We describe a case of intoxication in a 22-year-old male student after he mixed nutmeg with fruit juice and drank it. Neurological symptoms and anticholinergic signs were present during presentation. Conclusion: Nutmeg intoxication must be one of the possibilities considered at differential diagnosis in patients presenting to the emergency department with findings of anticholinergic intoxication.
- MakaleAçık Erişim2017Diagnostic Value of Cyclophilin A in Acute Ischemic Stroke
Karaca, Yunus; Tatli, Ozgur; Eryigit, Umut; Aksüt, Nurhak; Sahin, Aynur; Mentese, Ahmet; Altay, Diler Us; Beslioglu, Necla; Karatas, Mevlut; Örem, Asim
Aim: The early diagnosis and treatment of patients presenting to the emergency department symptoms of stroke can significantly reduce mortality and morbidity rates associated with it. This study aimed to investigate the diagnostic value of serum yclophilin A levels in our study group who presented to the emergency department with symptoms of acute ischemic stroke. Materials and Methods: In total, 114 patients diagnosed with acute ischemic stroke between October 2013 and October 2014 and a control group of 66 healthy volunteers were included. Cyclophilin A levels in the patient and control groups were compared. Results: The median cyclophilin A levels in the patient and control groups measured at the time of presentation were 13.47 (11.97-17.92) ng/mL and 11.54 (8.48-16.22) ng/mL, respectively. These levels were significantly higher in the patient group than in the control group (p<0.05). Conclusion: Plasma cyclophilin A levels were significantly higher in the patient group than in the control group.
- MakaleYalnız künye2017Carbonic anhydrase I and II autoantibodies in Behcet's disease
Mentese, A.; Alver, A.; Demir, S.; Sumer, A.; Yaman S, Ozer; Karkucak, M.; Capkin A, Aydin; Us, Altay D.; Turan, I
Background: Behcet's disease ( BD) is a vasculitis, seen more frequently around the Mediterranean and the Far East, and evinces with oral and genital ulcerations, skin lesions and uveitis. Carbonic anhydrase ( CA) is a metalloenzyme which is widely distributed in the living world, and it is essential for the regulation of acid-base balance. Anti-CA antibodies have been reported in many disorders, such as systemic lupus erythematosus, Sjogren's syndrome, rheumatoid arthritis, endometriosis, idiopathic chronic pancreatitis, type 1 diabetes and Graves' disease. The goal of this study was to investigate CA I and II autoantibodies in BD. Methods: 35 patients with BD and 29 healthy controls were included in the study and CA I and II autoantibody levels were investigated by ELISA. Results: The CA I and II autoantibody levels of BD group were significantly higher than the healthy group (p= 0.013, p= 0.0001, respectively). A cut-off value of 0.250 absorbance unit (ABSU) for anti-CA I was associated with 34% sensitivity and 100% specificity and a cut-off value of 0.171 ABSU for anti-CA II was associated with 54% sensitivity and 100% specificity for predicting BD. Conclusion: The CA I and II autoantibody levels in pa-tients with BD were found higher compared to control group and the results suggest that CA I and II autoantibodies may be involved in the pathogenesis of BD