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Publication Metadata only Complexation and mutagenicity potential studies with N,N′-bis(2- hydroxynaphthalin-1-carbaldehydene)-1,2-bis-(p-aminophenoxy)ethane and a novel oxovanadium(IV) complex(2004) Temel, Hamdi̊; Çakir, Ümit; Tolan, Veysel; Otludil, Birol; Uǧraş, Halil Ibráhim; Temel, Hamdi̊, Department of Chemistry, Dicle Üniversitesi, Diyarbakir, Turkey; Çakir, Ümit, Department of Chemistry, Bahçeşehir Üniversitesi, Istanbul, Turkey; Tolan, Veysel, Department of Biology, Dicle Üniversitesi, Diyarbakir, Turkey; Otludil, Birol, Department of Biology, Dicle Üniversitesi, Diyarbakir, Turkey; Uǧraş, Halil Ibráhim, Department of Chemistry, Bahçeşehir Üniversitesi, Istanbul, TurkeyA new oxovanadium(IV) complex of the Schiff base obtained by condensation of 1,2-bis(p-aminophenoxy)ethane with 2-hydroxynaphthalin-1-carbaldehyde was synthesized. The complex was characterized by elemental analysis, magnetic measurements, mass spectral data, UV-visible and IR spectra. Stability constants and thermodynamic values for complexation between Cu(NO3) 2, Zn(NO3)2·6H2O, Ni(NO 3)2·6H2O and VOSO4· 5H2O and the ligand in 80% dioxane/water were determined by conductance measurements. Ni(II) and Cu(II) complexes of the ligand synthesized by a previously described method were found to be mutagens on strain TA 100 in the presence and absence of S9 mix. These compounds are classified as mutagenic in the Ames test. © 2008 Elsevier B.V., All rights reserved.Publication Metadata only Sources of trace elements in total diet: A statistical approach(2004) Aras, Namik K.; Chatt, Amares; Aras, Namik K., Bahçeşehir Üniversitesi, Istanbul, Turkey; Chatt, Amares, Department of Chemistry, Dalhousie University, Halifax, CanadaWe have collected sixteen total diet samples from two socioeconomic groups in Turkey by duplicate portion techniques. Samples were homogenized with titanium-blade homogenizer, freeze dried and analyzed for their minor and trace elements mostly by neutron activation analysis. Bread and flour samples were also collected from the same regions and analyzed similarly by instrumental neutron activation analysis. We have determined concentrations of more than 25 elements in total diets, bread and flour, and fiber and phytate in total diets. We have determined daily dietary intakes of these population groups, probable source of elements through correlation coefficients, and enrichment factor calculations. © 2012 Elsevier B.V., All rights reserved.Publication Metadata only A direct-sequence spread-spectrum communication system for integrated sensor microsystems(2005) Aydın, Nizamettin; Arslan, Tughrul S.; Cumming, David R.S.; Aydın, Nizamettin, School of Engineering and Electronics, The University of Edinburgh, Edinburgh, United Kingdom, Department of Computer Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Arslan, Tughrul S., School of Engineering and Electronics, The University of Edinburgh, Edinburgh, United Kingdom, Institute for System Level Integration, Edinburgh, United Kingdom; Cumming, David R.S., Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow, United KingdomSome of the most important challenges in health-care technologies have been identified to be development of noninvasive systems and miniaturization. In developing the core technologies, progress is required in pushing the limits of miniaturization, minimizing the costs and power consumption of microsystems components, developing mobile/ wireless communication infrastructures and computing technologies that are reliable. The implementation of such miniaturized systems has become feasible by the advent of system-on-chip technology, which enables us to integrate most of the components of a system on to a single chip. One of the most important tasks in such a system is to convey information reliably on a multiple-access-based environment. When considering the design of telecommunication system for such a network, the receiver is the key performance critical block. The paper describes the application environment, the choice of the communication protocol, the implementation of the transmitter and receiver circuitry, and research work carried out on studying the impact of input data characteristics and internal data path complexity on area and power performance of the receiver. We provide results using a test data recorded from a pH sensor. The results demonstrate satisfying functionality, area, and power constraints even when a degree of programmability is incorporated in the system. © 2005 IEEE. © 2008 Elsevier B.V., All rights reserved.Publication Metadata only Decolorization of Remazol Yellow RR Gran by white rot fungus Phanerochaete chrysosporium(Triveni Enterprises, 2007) Demir, Goksel; Özcan, Hüseyin Kurtuluş; Tüfekçi, Neşe; Borat, Mehmet; Demir, Goksel, Department of Environmental Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Özcan, Hüseyin Kurtuluş, Department of Environmental Engineering, Istanbul Üniversitesi, Istanbul, Turkey; Tüfekçi, Neşe, Department of Environmental Engineering, Istanbul Üniversitesi, Istanbul, Turkey; Borat, Mehmet, Department of Environmental Engineering, Fatih Üniversitesi, Istanbul, TurkeyIn this study, the removal of color, chemical oxygen demand (COD) and aromatic group from one of the azo dyes, Remazol Yellow RR Gran, had been carried out by using one of the white rot fungi, Phanerochaete chrysosporium. Experimental studies were performed in growth media containing different amounts of dye and glucose. Color measurements were done at 436 nm wavelength using spectrophotometer, while aromatic group measurements were done at 280 nm wavelength using UV/Visible spectrophotometer. As a result of this study, the values of the removable color concentration were determined as 10 mgl -1 and lower. The optimum medium glucose concentration was determined to be 2 gl-1 during color removal processes, aromatic group measurements were done in samples in the UV region at 280 nm wavelength. As a result of the measurements, it was shown that certain amount of aromatic group remained in the model wastewater at the end of the process. © Triveni Enterprises. © 2020 Elsevier B.V., All rights reserved.Publication Metadata only Prediction of cyclosporine A blood levels: An application of the adaptive-network-based fuzzy inference system (ANFIS) in assisting drug therapy(2008) Gören, Sezer; Karahoca, Adem; Onat, Filiz Yilmaz; Gören, Mehmet Zafer; Gören, Sezer, Department of Computer Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Karahoca, Adem, Department of Computer Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Onat, Filiz Yilmaz, Department of Pharmacology and Clinical Pharmacology, Marmara Üniversitesi Tip Fakültesi, Istanbul, Turkey; Gören, Mehmet Zafer, Department of Pharmacology and Clinical Pharmacology, Marmara Üniversitesi Tip Fakültesi, Istanbul, TurkeyObjective: Therapeutic drug monitoring (TDM) is a procedure in which the levels of drugs are assayed in various body fluids with the aim of individualizing the dose of critical drugs, such as cyclosporine A. Cyclosporine A assays are performed in blood. Methods: We proposed the use of the Takagi and Sugeno-type adaptive-network-based fuzzy inference system (ANFIS) to predict the concentration of cyclosporine A in blood samples taken from renal transplantation patients. We implemented the ANFIS model using TDM data collected from 138 patients and 20 input parameters. Input parameters for the model consisted of concurrent use of drugs, blood levels, sampling time, age, gender, and dosing intervals. Results: Fuzzy modeling produced eight rules. The developed ANFIS model exhibited a root mean square error (RMSE) of 0.045 with respect to the training data and an error of 0.057 with respect to the checking data in the MATLAB environment. Conclusion: ANFIS can effectively assist physicians in choosing best therapeutic drug dose in the clinical setting. © 2008 Springer-Verlag. © 2009 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.Publication Metadata only Prediction of tropospheric ozone concentration by employing artificial neural networks(2008) Ozdemir, Huseyin; Demir, Goksel; Altay, Gökmen; Albayrak, Sefika; Bayat, Cuma; Ozdemir, Huseyin, Department of Environmental Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Demir, Goksel, Department of Environmental Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Altay, Gökmen, Department of Electrical and Electronic Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Albayrak, Sefika, Department of Environmental Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Bayat, Cuma, T.C. Beykent Üniversitesi, Istanbul, TurkeyAir pollution modeling and prediction have great importance in preventing the occurrence of air pollution episodes and provide sufficient time to take the necessary precautions. Recently various algorithms such as artificial neural networks (ANNs) is applied to air quality modeling. The present work aims to predict tropospheric ozone concentration by the ANN with three pollutant parameters and eight meteorological factors in selected areas. We have preferred three-layer perceptron type of ANNs, which consists of input, hidden, and output layers, respectively. To evaluate the performance of the ANN model, selected statistical performance parameters are used. The overall system finds correlation parameter, r between 0.8 and 0.9 for the test data sets. Therefore, results show the successful follow of estimated ozone concentrations by the model with the observed values. Finally, it was seen that the ANN is one of the compromising methods in estimation of environmental complex air pollution problems. © Mary Ann Liebert, Inc. 2008. © 2008 Elsevier B.V., All rights reserved.Publication Metadata only Importance of particulate biodegradable organic compounds in performance of full-scale biological phosphorus removal system(Water Environment Federation, 2009) Tunçal, Tolga; Pala, Ayşegül Iyilikçi; Uslu, Orhan; Tunçal, Tolga, The Graduate School of Natural and Applied Sciences, Dokuz Eylül Üniversitesi, Izmir, Turkey, Izmir Water and Sewerage Administration (IZSU), Tuzla, Turkey; Pala, Ayşegül Iyilikçi, Environmental Engineering Department, Dokuz Eylül Üniversitesi, Izmir, Turkey; Uslu, Orhan, Environmental Engineering Department, Bahçeşehir Üniversitesi, Istanbul, TurkeyIn this study, biological treatment performances of two parallel treatment lines operating with and without primary sedimentation were investigated. The research was carried out in a large-scale enhanced biological phosphorus removal (EBPR) process. Influent and effluent of treatment lines were characterized continuously during the study. In addition, anaerobic anoxic and aerobic EBPR activities were investigated by batch tests using fresh activated sludge samples. All of the environmental and operational conditions of the treatment lines were statistically compared. Evaluation of effluent compositions indicated that EBPR performances of treatment lines were significantly different. Results of the research also indicated that settling characteristics of the activated sludge process could be improved significantly with increasing particulate biodegradable organic compound (pbCOD) loading rate. Batch test results revealed that anaerobic, anoxic, and aerobic biochemical reaction rates of activated sludge cultivated on increased pbCOD loading rate were significantly higher compared to activated sludge cultivated on soluble substrate forms. © 2018 Elsevier B.V., All rights reserved.Publication Metadata only Caregiving style, problem solving strategies, anger style and health status in women caregivers of alzheimer patients and healthy elderly, Alzhei̇mer hastalarina ve saǧlikli yaşlilara bakimveren kadin yakinlarda bakim verme tarzi, problem çözme strateji̇leri̇,öfke tarzlari ve saǧlik durumunun i̇ncelenmeṡi(2009) Korkut, Yeflim; Sertel-Berk, Hanife Özlem; Korkut, Yeflim, Bahçeşehir Üniversitesi, Istanbul, Turkey; Sertel-Berk, Hanife Özlem, Psikoloji Anabilim Dali, Istanbul Üniversitesi, Istanbul, TurkeyIntroduction: The principle aim of this study is to investigate the caregiving style of the participants and the kind of support they receive, to compare anger levels, problem solving approaches and health problems of Alzheimer Disease (AD) patient female caregivers with a control group. This study further examines the effect of group, age, health status, anger style and problem solving style on depression. Materials and Method: 42 female caregivers (22 AD and 20 control) participated in the study. They were given a demographic questionnaire, Beck Depression Inventory-BDI, State-Trait Anger Scale-STAS and Problem Solving Inventory-PSI. Results: Results indicated that both AD and control group caregivers were similar in terms of caregiving style. Though AD and control group caregivers did not differ in terms PSI and BDI, there were significant differences between those who reported illness and those who did not in terms of impatient and thoughtful approach sub-tests of PSI. The regression analysis showed that age and repressed anger significantly explained the variation in BDI. Conclusion: Altogether results showed that in a relatively low at risk women caregivers group, regardless of being AD caregiver or not, age and repressed anger are important factors on depression levels. Health status of caregiver seems to be a determining factor on PSI. © 2009 Elsevier B.V., All rights reserved.Publication Metadata only A comprehensive model of simultaneous denitrification and methanogenic fermentation processes(2010) Tugtas, Adile Evren; Tezel, Ulaş; Pavlostathis, Spyros G.; Tugtas, Adile Evren, Department of Environmental Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Tezel, Ulaş, College of Engineering, Atlanta, United States; Pavlostathis, Spyros G., College of Engineering, Atlanta, United StatesThe denitrification process was incorporated into the IWA Anaerobic Digestion Model No. 1 (ADM1) in order to account for the effect of denitrification on the methanogenic fermentation process. The model was calibrated and optimized using previously published experimental data and kinetic parameter values obtained with a mixed, mesophilic (358C) methanogenic culture. Model simulations were used to predict the effect of nitrate reduction on the methanogenic fermentation process in batch, semi-continuous, and continuous flow reactors experiencing operational changes and/or system disturbances. The extended model clearly revealed the importance of substrate competition between denitrifiers and non-denitrifiers as well as the impact of N-oxide inhibition on process interactions between fermentation, methanogenesis, and denitrification. © 2009 Wiley Periodicals, Inc. © 2010 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.Publication Metadata only A source separation approach to enhancing marine mammal vocalizations(2009) Gür, M. Berke; Niezrecki, Christopher; Gür, M. Berke, Department of Mechanical Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Niezrecki, Christopher, Francis College of Engineering, Lowell, United StatesA common problem in passive acoustic based marine mammal monitoring is the contamination of vocalizations by a noise source, such as a surface vessel. The conventional approach in improving the vocalization signal to noise ratio (SNR) is to suppress the unwanted noise sources by beamforming the measurements made using an array. In this paper, an alternative approach to multi-channel underwater signal enhancement is proposed. Specifically, a blind source separation algorithm that extracts the vocalization signal from two-channel noisy measurements is derived and implemented. The proposed algorithm uses a robust decorrelation criterion to separate the vocalization from background noise, and hence is suitable for low SNR measurements. To overcome the convergence limitations resulting from temporally correlated recordings, the supervised affine projection filter update rule is adapted to the unsupervised source separation framework. The proposed method is evaluated using real West Indian manatee (Trichechus manatus latirostris) vocalizations and watercraft emitted noise measurements made within a typical manatee habitat in Florida. The results suggest that the proposed algorithm can improve the detection range of a passive acoustic detector five times on average (for input SNR between -10 and 5 dB) using only two receivers. © 2009 Acoustical Society of America. © 2010 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.