Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleYalnız künye2017Scopus SJRQ1
    Combustion properties of impregnated spruce (Picea orientalis L.) wood

    Şadiye Yasar, Ş.; Said Fidan, M.; Yaşar, Mehmet; Atar, Musa; Alkan, Elif

    Wooden material is one of the most commonly used construction materials since history of humanity due to its environment friendly and renewable natural source. This structure of wood material is also preferred because it is lightweight, easy to work, resistant to factors such as earthquake and fire, as compared to other used building materials. However, organic structure of the wooden material causes it to be affected negatively because of damages that might occur outdoors under inappropriate conditions. Due to this reason, in this study were investigated effects of various chemicals (impregnated and varnish type), used to prevent environmental damages (biotic, abiotic pests, fire etc.) on combustion resistance of the wood exposed to air conditions for a year. For this purpose, prepared Caucasian spruce (Picea orientalis L.) specimens were surface treated (synthetic and water-based varnish) after impregnated according to ASTM-D 1413-76 principles with various chemicals (Tanalith-E and Wolmanit-CB). Test specimens with impregnated, varnished and processless, were left in outdoor conditions for a year. Combustion experiment was conducted according to the principles in ASTM-E 160-50 combustion test standards. According to the results of the experiment, control and year specimens had close results in the weight loss. Weight loss was found be lower Wolmanit-CB impregnated specimens (92.12%) among the impregnated materials to synthetic varnish coated specimens (% 91.89) among the varnished specimens. It was determined that using Wolmanit-CB for impregnating and synthetic varnish for varnishing would be better according to the results. Furthermore, the amount of O2 (25.84 ppm) in control specimens in combustion with flame; the amounts of CO and CO2 (31787, 19.92 ppm respectively) in year specimens in combustion without flame and the amount of NO (54.65 ppm) in year specimens in glowing was observed to be the highest.

    • SDG 12 · Sorumlu Üretim ve Tüketim
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  • MakaleYalnız künye2017Scopus SJRQ2
    Effect of powder of macaroni boiling water (by-product) on textural, oil uptake, physico-chemical, sensory and morphological properties of fried wheat chips

    Yuksel, Ferhat

    The current study was conducted with the purpose to produce wheat chips enriched with powder of pasta boiling water (PPBW). Pasting properties of chips dough changed with addition of powder of pasta boiling water. The textural properties of dough samples decreased with the addition of PPBW, but there were no differences between 2nd and 3rd samples including 10 and 20 % PPBW. The oil content of the samples decreased with the increase of PPBW from 33.78 to 22.19 %. The morphological analysis showed that the number of pores and pore size decreased with the addition of PPBW. Maximum overall acceptability score of the samples was given for control samples (5.64) while the overall acceptability of samples with 10 % PPBW was close to control sample (5.14). PPBW may be used in the formulation of chips it may be used to be coating matter for snacks in food industry.

    • SDG 2 · Açlığa Son
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  • BildiriYalnız künye2017
    Statistical analysis of fundamental seismotectonic parameters for future Earthquake occurrences in tunceli province of Turkey

    Öztürk, S.

    An evaluation based on Gutenberg-Richter b-value, fractal dimension Dc-value, completeness magnitude Mc-value, annual probability and recurrence time of earthquakes is carried out for Tunceli province of Turkey. Earthquake catalog covers the years between 21 September 1970 and 30 December 2016, and contains 5462 earthquakes with magnitude equal to and greater than 1.1. Magnitude completeness is estimated as 2.8 and b-value is found as b=0.98+/-0.01. This b-value is smaller than average value of b=1.0 given for Gutenberg-Richter relation. So, this low b-value may be an indicator of stress to build up over time at the beginning of 2017. Dc-value is obtained as 1.63+/-0.04 with 95% confidence limits. This high Dc-value indicates that seismicity in Tunceli and vicinity is more clustered at larger scales or in smaller areas. Annual probability of the earthquakes between 4.5 and 5.5 magnitude levels exhibits a value between 1 and 10. Recurrence time of the earthquakes has a value between 10 and 30 years for magnitude levels between 5.5 and 6.0, and a value between 30 and 100 years for magnitude levels between 6.0 and 6.5. Consequently, this part of Turkey may have an earthquake potential for the possibility of intense earthquake occurrences in the next future.

  • BildiriYalnız künye2017
    Determination of the dynamic characteristics of the faculty building of engineering and natural science with hvsr method and fsr method

    Beker, Y.; Sayıl, N.

    Seismic response characteristics of structures can be estimated by spectral ratios of microtremors measured on structures and their foundation ground surface. The microtremor horizontal-to-vertical-spectral-ratio (HVSR) technique has received great attention from all over the world with its simplicity together with quick information about dynamic characteristics of ground and structures. The HVSR of microtremors gives a good estimation of natural building frequency. In this study, Nakamura (H/V) method and Floor Spectral Ratio Method (FSR) has been applied to microtremor records taken with three component broad band velocity seismometers in seven different locations inside the building (ground floor; east and west side for second, fourth and sixth floor) and one at outside with the aim of determining the dynamic characteristics of Faculty building of Engineering and Natural Science at Gumushane University, in NE Turkey. The average predominant frequency, period and amplification values for the Faculty building are calculated. The ratio of amplitude spectrum of the upper floors to amplitude spectrum of the ground floor for both of horizontal components (East-West, North-South) is determined using FSR Method. The vibration frequency and period is around 4.0 Hz and 0.332 s, respectively. Also, the damping ratio and vulnerability were calculated to the Faculty building.

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  • MakaleYayıncıda açık erişim2017Scopus SJRQ2
    Analysis of the changes in forest ecosystem functions, structure and composition in the Black Sea region of Turkey

    Keleş, Sedat; Durusoy, İdris; Çakir, Günay

    We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability: economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types, tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas (especially in settlement and agricultural areas), forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.

    • SDG 15 · Karasal Yaşam
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  • MakaleYalnız künye2017Scopus SJRQ3
    In situ gamma ray measurements for deciphering of radioactivity level in Sarıhan pluton area of northeastern Turkey

    Çınar, Hakan; Altundaş, Suna; Çelik, Necati; Maden, Nafız

    The present work utilizes in situ gamma ray spectrometric measurement data to map the surface geology of Sarıhan Granitoid and its surrounding area. The study area comprises three different lithological units, namely, Hozbirikyayla Formation (limestone and sandy limestones), Sarıhan Granitoid (consist of quartz monzodiorite, granodiorite and quartz diorite) and the Ophiolitic olistostromal melange (andesite, basalt, sandstone, gravelly sandstone). When lithological units are assessed according to the radioactivity characteristics, natural radionuclide contents (40K and radionuclides from 238U and 232Th series) of Hozbirikyayla limestones and ophiolitic melange rocks are lower than the Sarıhan pluton. The U, Th and K radionuclide contents were found to be 0.8–5.4 ppm, 10.1–33.6 ppm and 1.29–4.41% in the Sarıhan plutonic area and 0.9–5.3 ppm, 1.1–20.3 ppm and 0.04–2.71% in Horzbirikyayla formation, respectively. The element concentrations of 238U, 232Th and 40K of the Ophiolitic melange are 1.1–4.5 ppm, 1.6–25.3 ppm and 0.09–3.63%, respectively. Radioelement ratio maps are created for the studied area, because the parameters of radioelement ratios, eU/eTh, eU/K and eTh/K, reflect the radioactive characters of the rock and soil. The Hozbirikyayla Formation is characterized by the highest value of eU/eTh and lowest value of eTh/K. While the lowest eU/eTh and eU/K ratios were observed in the Sarıhan Granodiorite, the highest value of eU/K and eTh/K were obtained in the Ophiolitic olistostromal melange. By comparing these maps with the geology, it was found that the radioelement concentrations are in good agreement with the geological properties of the region. In addition to this, the radiation hazard parameters were evaluated to assess the radiation hazard for people living in this area. It has also been found that there is no significant radiologic hazard for humans and the environment in and around studied area.

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  • MakaleYalnız künye2017Scopus SJRQ2
    How does corporate social responsibility create customer loyalty? the role of corporate image

    Gürlek, Mert; Düzgün, Ertugrul; Uygur, Selma Meydan

    Purpose - This paper aims to investigate whether corporate image has a mediating effect on the influence of corporate social responsibility (CSR) on customer loyalty in independent hotels. Design/methodology/approach - Data were collected from customers of five-star hotels located in Istanbul in Turkey. The theoretical model was tested with 404 usable data. The results were analyzed by using structural equation modeling (SEM). Findings - Findings show that CSR creates customer loyalty partially through corporate image in the independent hotels. In addition, it was found that the hotels included in the study carried out moderate level of CSR activities. Research limitations/implications - The research model was tested in independent five-star hotels. Further studies could be carried out using different independent hospitality companies. In addition, the research was conducted on a limited sample, as hotel managers were not willing to allow direct contact with customers. Further studies could be carried out on larger samples. Practical implications - This study recommends that independent hotels carry out more CSR activities on social and environmental issues. In addition, direct effect of CSR on customer loyalty is lower than its indirect effect via corporate image. Therefore, if companies desire to create customer loyalty through CSR, they should introduce their CSR activities to customers via communication tools (website, media etc.) Originality/value - This study examines CSR in terms of sustainable development in the independent hotels. Furthermore, it explains relationships between CSR and corporate image and customer loyalty through the principle of generalized reciprocity specified in the theory of social change.

    AtıfScopus140WoS123OpenAlex175
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  • MakaleYalnız künye2017Scopus SJRQ1
    Formation of the Eğrikar (Gümüşhane) Fe–Cu skarn type mineralization in NE Turkey: U–Pb zircon age, lithogeochemistry, mineral chemistry, fluid inclusion, and O-H-C-S isotopic compositions

    Sipahi, Ferkan; Akpınar, İbrahim; Eker, Çiğdem Saydam; Kaygusuz, Abdullah; Vural, Alaaddin; Yılmaz, Meltem

    The Eğrikar Fe–Cu skarn type mineralization is located approximately 100 km NW of Gümüşhane in NE Turkey. Geochemical analyses of diorite, which is thought to cause skarn, indicate medium K calc-alkaline (1.3 to ~ 2.3 wt% K2O), metaluminous to peraluminous (A/CNK = 0.76 to 1.13) and resembles a continental arc granite. The age of U–Pb zircon obtained from diorite is 42.3 ± 1.0 Ma, which reflects the age of skarn metasomatism after intrusion into Late Cretaceous sandy carbonates. Skarn formation zones are recognized as endo- and exoskarn. The endoskarn zone mainly consists of pyroxene with hedenbergite (Di4.31–28.14Hd59.29–80.82Jo5.0–35.55) at prograde stage. Mn content of pyroxene increases a slight from endo to exoskarn. Pyroxene is replaced by epidote and hornblende at the retrograde stage. The exoskarn zone comprises garnet with andradite (Ad91-99Gr01–07) and grossular-andradite (Ad44-95Gr05–54), epidote and quartz as silicate minerals, and magnetite and hematite as ore minerals. Magnetite is the abundant ore mineral and is accompanied by chalcopyrite and minor pyrite at retrograde stage. On the basis of fluid inclusion values of minerals, the temperature range for hedenbergite in endo-exoskarn is 350 °C–425 °C, for epidote in exoskarn is 365 °C–376 °C, and for quartz in exoskarn 200 °C–380 °C. NaCl equivalent salinity for hedenbergite 6.88–10.73 wt% and for quartz is 3.9–15.38 wt. The δ18O values of hedenbergite is 4.1 to 4.7‰ and for garnet 3.4‰ at prograde stage, for epidote 7.9–9.2‰, for magnetite 1 to 4.4‰, for hematite − 2.9 to − 1.6‰ and for quartz range between 8.5‰ and 15.2‰. The δ18O value of epidote suggests that oxygen is a magmatic fluid whereas hedenbergite, garnet, quartz and magnetite show the mixing of magmatic and meteoric fluids. In addition, the C isotope values (− 3.2 to 2.8‰) of calcite and marble in Eğrikar Fe–Cu skarn reflect those of metamorphic, and skarns. Based on oxygen isotope data from mineral pairs, the retrograde skarn formation is characterized by epidote–magnetite assemblage formed at 255 °C–438 °C. Fluid oxygen isotope compositions of magnetite and epidote pairs of the exoskarn skarn zone indicate a mixing of magmatic and meteoric fluids with narrow δ18O values between 7.17‰ and 8.9‰. The δ34S values of the pyrites exhibit a narrow range of 3‰ and 4.4‰, thereby indicating that sulfur were probably leached from magmatic rocks. Based on the field and laboratory observation, mineral chemistries, fluid inclusion studies and isotope composition analysis, it is suggested that the Eğrikar Fe–Cu skarn mineralization occurs in a magmatic origin fluids being initially under reduced conditions, subsequently under oxidized conditions, and at shallow depth.

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  • MakaleYalnız künye2017Scopus SJRQ3
    Selection application of material to be used in hip prosthesis production with analytic hierarchy process: Anwendungsselektion des zu verwendenden Materials in der Hüftprothesenproduktion mit dem analytischen Hierarchieverfahren

    Çelik, İ.; Eroğlu, H.

    Metallic biomaterials used in making hip prosthesis are required to meet expectations in terms of fatigue strength, corrosion resistance, wear resistance, cost and biocompatibility. It is also desirable that the modulus of elasticity they possess is close to the level of the possible bone. Metallic biomaterials face the problem of ion release even though they meet the criteria mentioned above. As a result, the choice of metallic material to be preferred in the manufacture of hip prosthesis can be made by evaluating all these criteria among themselves and by the performances of biomaterials to be compared according to these criteria. In this study, firstly the criteria expected from the metals to be used as biomaterials have been determined. Expert opinions about the subject and criteria determined in accordance with the studies in the literature by using analytical hierarchy process have been graded according to each other. Afterwards, selection of the most appropriate material was ensured by making the order of importance according to the criteria of the candidate materials.

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  • MakaleYalnız künye2017Scopus SJRQ4
    Effects of certain drugs on dihydropyrimidine dehydrogenase enzyme purified from bovine liver

    Aygul, Imdat; Ozdemir, Hasan; Ciftci, Mehmet

    The inhibitory effects of certain drugs on dihydropyrimidine dehydrogenase from the bovine liver have been investigated. Dihydropyrimidine dehydrogenase [5, 6-dihydrouracil: NADP+ oxidoreductase, EC 1.3.1.2; DPD] enzyme was purified from the bovine liver. The purification was performed by preparation of homogenate, ammonium sulphate precipitation, and affinity chromatography. Moreover, some important modifications were made in the purification procedure. Purification of bovine liver DPD enzyme was obtained with a yield of 12.5%. SDS polyacrylamide gel electrophoresis was performed after the purification of the enzyme, and the electrophoretic pattern is discussed in this article. In addition, the effects of certain drugs on bovine liver dihydropyrimidine dehydrogenase enzyme activity were investigated. Oxytetracycline, ciprofloxacin, ceftazidime, cefoperazone, amikacin, ornidazole, metronidazole, cefuroxime, cefepime, ampicillin, and amoxicillin, were used as drugs. All the drugs indicated the inhibitory effects on the enzyme. IC50 values of the drugs were determined by plotting activity % vs [I]. IC50 values of oxytetracycline, ciprofloxacin, ceftazidime, cefoperazone, amikacin, ornidazole, metronidazole, cefuroxime, cefepime, ampicillin, and amoxicillin 0.030, 0.046, 0.140, 0.610,1.820, 2.500, 3.600, 4.330, 4.370, 4.920, and 6.300, mM; the Ki constants were 0.050±0.01,0.090± 0.06, 0.130±0.045, 0.185±0.057, 2.010±0.55, 2.096±1.06, 2.115±1.00, 2.700±0.56, 3.730±1.48, 5.240±1.04, and 9.570±2.84, mM for bovine liver DPD, respectively. Ki constants for dihydropyrimidine dehydrogenase were determined by Lineweaver-Burk graphs. All drugs showed non-competitive inhibition patterns.

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  • MakaleYalnız künye2017Scopus SJRQ1
    Low-complexity early termination method for rateless soft decoder

    Albayrak, Cenk; Simsek, Cemaleddin; Turk, Kadir

    We propose a new early termination method (ETM) with low computational complexity for Luby transform belief propagation (BP) decoder. The proposed method, which we call least reliable messages (LRM) ETM, observes only sign alterations of a small cluster in log-likelihood ratio messages passing between nodes in BP decoder. Simulation results and complexity analyzes show that LRM ETM has quite low computational complexity and small average iteration amounts without any performance degradation compared with conventional ETMs in literature. The method can be applied to code families which can be decoded by BP such as low density parity check codes, polar codes, and Raptor codes.

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  • MakaleYalnız künye2017Scopus SJRQ2
    An Investigation of Corrosion Resistance and Antibacterial Sensitivity Properties of Nano-Ag-Doped TiO 2 Coating and TiO 2 Coating Grown on NiTi Alloy with the Micro-Arc Oxidation Process

    Karabudak, Filiz; Yeşildal, Ruhi; Şüküroğlu, Ebru Emine; Şüküroğlu, Süleyman; Zamanlou, Hamid; Dikbaş, Neslihan; Bayındır, Funda; Şen, Sadri; Totik, Yaşar

    In this study, TiO 2 coatings were grown with nano-Ag doped and micro-arc oxidation technique on NiTi shape memory alloy. The antibacterial sensitivity and corrosion resistance characteristics of both coatings were investigated. The microstructure and composition analyses of the coatings were performed with scanning electron microscope, energy dispersive X-ray spectrometry, and X-Ray diffraction (XRD). The XRD results showed that there were only TiO 2 crystal phases (anatase and rutile) on the coating. The results showed that a clean and dense oxide layer was grown on the surface successfully. The surface of nano-Ag-doped TiO 2-coated samples appear to be smoother than the surface of the coatings without Ag. The corrosion tests of the coated and uncoated samples were carried out in three different environments (simulated body fluid, synthetic saliva, and cola) at 37 ∘ which is human body temperature. The corrosion tests showed that the corrosion resistance of TiO 2-coated and nano-Ag-doped TiO 2-coated samples was much higher than the corrosion resistance of the NiTi substrate. Seven different bacteria including (S. aureus, L. monocytogenes, Bacillus subtilis, Salmonella enteritidis, Yersinia enterocolitica, and E. coli, P.aeruginosa) which have the human pathogen feature were used in the antibacterial susceptibility tests. The process was conducted based on the disk diffusion method to test the susceptibility of bacterial strains on the selected coated and uncoated samples, and antimicrobial activity was evaluated in the nano-Ag-doped TiO 2-coated material; P.aeruginosa, Y. enterocolitica, and E. coli (zone diameter of 8–14 mm) were found to be moderately susceptible; S. aureus, L. monocytogenes, B. subtilis, and S. enteritidis (zone diameters of 8–14 mm) were found to be resistant. The antimicrobial activity of the coating material NiTi was found to be sensitive for all antibacterial tests. According to the TiO 2-coated material results, S. aureus, P.aeruginosa, L. monocytogenes, E. coli were found to be moderately sensitive and Y. enterocolitica, S. enteritidis, and B. subtilis were found to be resistant.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
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  • MakaleYalnız künye2017Scopus SJRQ3
    Remote sensing technique for capturing and exploration of mineral deposit sites in Gumushane metallogenic province, NE Turkey

    Vural, Alaaddin; Corumluoglu, Özsen; Asri, Ibrahim

    This study examines the determination and confirmation of mineral deposits in the Gumushane Province,Turkey. Rather than using classical techniques, Remote Sensing (RS) and Geographic Information System GIS technologies are applied for this purpose. Mineral alteration traces on the ground are characteristic indicators of ore below the surface. These traces can be determined using RS techniques. The Crosta technique is one of the most important RS image analysis methods used for the determination of mineral alterations. The technique has shown particular usefulness around mine areas, which are rich in ore deposits and show hydrothermal alterations. Therefore, four separate mine fields covering a total area of 718 km2 in the southern part of Gumushane, which is rich in iron oxides, hydroxides and hydrothermal alteration, were chosen. The Crosta technique was applied to the satellite image of each area to explore the regional alterations. The determined locations could be confirmed as alteration areas. Within these four regions, some other locations showing similar alteration patterns were also determined using the Crosta technique. These locations represent good candidates for mineral exploration.

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  • MakaleYalnız künye2017Scopus SJRQ3
    Effect of dc field on ac-loss peak in a commercial Bi:2223/Ag tape

    Öztürk, Ali; Düzgün, Ibrahim; Çelebi, Selahattin

    Measurements of the ac susceptibility in a commercial Bi:2223/Ag tape for some different ac magnetic field amplitudes, Hac, in the presence of bias magnetic field Hdc directed along Hac are reported. It is found that the peak values of the imaginary component of ac susceptibility χ″max versus Hac trace a valley for the orientation where applied field Ha perpendicular to wide face of the tape total. We note that the observation of the valley depends on various parameters such as field dependence parameter n in the critical current density, in the simple power law expression jc = α(T)/Bn, choice of the bias field Hdc together with selected ac field amplitudes Hac, and dimension and geometry of sample studied. Our calculations based on critical state model with jc = α(1 - T/Tcm)p/Bn using the fitting parameters of n = 0.25, p = 2.2, Tcm = 108 K gives quite good results to compare the experimental and calculated curves.

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  • MakaleYayıncıda açık erişim2017Scopus SJRQ2
    Evaluation of the contraceptive effects of carprofen, flunixin meglumine and meloxicam in rats

    Paksoy, Z.; Kirbas, A.

    The objective of this study was to determine the suitability of carprofen, flunixin meglumine and meloxicam for use in emergency contraception. Forty-eight pregnant Sprague-Dawley rats were used as material. Five groups were subjected to treatments while one group served as a control. The numbers of animals in each group were equal (n = 8). Treatment groups were administered carprofen (10 mg/kg, single or double dose, s.c.), flunixin meglumine (5 mg/kg, single or double dose, i.m.) and meloxicam (2 mg/kg, a single dose, s.c.) on the third day after mating. The control group received saline. The rats were sacrificed on Day 7 of gestation. Luteal spots and implantation sites were recorded. Pre-implantation loss was calculated by subtracting the number of luteal spots from the number of implantation sites. Compared with the control, the administration of flunixin meglumine (double dose), carprofen (double dose) and meloxicam highly significantly decreased the implantation rate (P < 0.001). Single dose administration of flunixin meglumine and carprofen led to significant decreases (P < 0.01). In conclusion, this study indicates that carprofen, flunixin meglumine and meloxicam treatment cause a decline in implantation rate in rats.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
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  • MakaleYalnız künye2017Scopus SJRQ2
    Genome 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.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus11WoS10OpenAlex12
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  • MakaleYalnız künye2017Scopus SJRQ1
    Comparison 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.

    AtıfScopus46WoS37OpenAlex42
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  • MakaleYalnız künye2017Scopus SJRQ2
    Geochemical 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.

    AtıfScopus10WoS9OpenAlex10
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  • MakaleYalnız künye2017Scopus SJRQ1
    Stereo-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.

    AtıfScopus34WoS24
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2017Scopus SJRQ1
    An 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.

    AtıfScopus42WoS34OpenAlex38
    ScopusWeb of SciencePubMedİncele