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Measurement Of Network-Based And Random Meetings In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud Jan 2019

Measurement Of Network-Based And Random Meetings In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud

Turkish Journal of Electrical Engineering and Computer Sciences

Social networks are created by the underlying behavior of the actors involved in them. Each actor has interactions with other actors in the network and these interactions decide whether a social relationship should develop between them. Such interactions may occur due to meeting processes such as chance-based meetings or network-based (choice) meetings. Depending upon which of these two types of interactions plays a greater role in creation of links, a social network shall evolve accordingly. This evolution shall result in the social network obtaining a suitable structure and certain unique features. The aim of this work is to determine the …


Automated Elimination Of Eog Artifacts In Sleep Eeg Using Regression Method, Mehmet Dursun, Seral Özşen, Sali̇h Güneş, Bayram Akdemi̇r, Şebnem Yosunkaya Jan 2019

Automated Elimination Of Eog Artifacts In Sleep Eeg Using Regression Method, Mehmet Dursun, Seral Özşen, Sali̇h Güneş, Bayram Akdemi̇r, Şebnem Yosunkaya

Turkish Journal of Electrical Engineering and Computer Sciences

Sleep electroencephalogram (EEG) signal is an important clinical tool for automatic sleep staging process. Sleep EEG signal is effected by artifacts and other biological signal sources, such as electrooculogram (EOG) and electromyogram (EMG), and since it is effected, its clinical utility reduces. Therefore, eliminating EOG artifacts from sleep EEG signal is a major challenge for automatic sleep staging. We have studied the effects of EOG signals on sleep EEG and tried to remove them from the EEG signals by using regression method. The EEG and EOG recordings of seven subjects were obtained from the Sleep Research Laboratory of Meram Medicine …


Polyhedral Conic Kernel-Like Functions For Svms, Gürkan Öztürk, Emre Çi̇men Jan 2019

Polyhedral Conic Kernel-Like Functions For Svms, Gürkan Öztürk, Emre Çi̇men

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we propose a new approach that can be used as a kernel-like function for support vector machines (SVMs) in order to get nonlinear classification surfaces. We combined polyhedral conic functions (PCFs) with the SVM method. To get nonlinear classification surfaces, kernel functions are used with SVMs. However, the parameter selection of the kernel function affects the classification accuracy. Generally, in order to get successful classifiers which can predict unknown data accurately, best parameters are explored with the grid search method which is computationally expensive. We solved this problem with the proposed method. There is no need to …


Understanding Attribute And Social Circle Correlation In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud Jan 2019

Understanding Attribute And Social Circle Correlation In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud

Turkish Journal of Electrical Engineering and Computer Sciences

Social circles, groups, lists, etc. are functionalities that allow users of online social network (OSN) platforms to manually organize their social media contacts. However, this facility provided by OSNs has not received appreciation from users due to the tedious nature of the task of organizing the ones that are only contacted periodically. In view of the numerous benefits of this functionality, it may be advantageous to investigate measures that lead to enhancements in its efficacy by allowing for automatic creation of customized groups of users (social circles, groups, lists, etc). The field of study for this purpose, i.e. creating coarse-grained …


A Novel Accuracy Assessment Model For Video Stabilization Approaches Based On Background Motion, Md Alamgir Hossain, Tien-Dung Nguyen, Eui Nam Huh Jan 2019

A Novel Accuracy Assessment Model For Video Stabilization Approaches Based On Background Motion, Md Alamgir Hossain, Tien-Dung Nguyen, Eui Nam Huh

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a new accuracy measurement model for the video stabilization method based on background motion that can accurately measure the performance of the video stabilization algorithm. Undesired residual motion present in the video can quantitatively be measured by the pixel by pixel background motion displacement between two consecutive background frames. First of all, foregrounds are removed from a stabilized video, and then we find the two-dimensional flow vectors for each pixel separately between two consecutive background frames. After that, we calculate a Euclidean distance between these two flow vectors for each pixel one by one, which …


An Improved Tree Model Based On Ensemble Feature Selection For Classification, Chandralekha M, Shenbagavadivu N Jan 2019

An Improved Tree Model Based On Ensemble Feature Selection For Classification, Chandralekha M, Shenbagavadivu N

Turkish Journal of Electrical Engineering and Computer Sciences

Researchers train and build specific models to classify the presence and absence of a disease and the accuracy of such classification models is continuously improved. The process of building a model and training depends on the medical data utilized. Various machine learning techniques and tools are used to handle different data with respect to disease types and their clinical conditions. Classification is the most widely used technique to classify disease and the accuracy of the classifier largely depends on the attributes. The choice of the attribute largely affects the diagnosis and performance of the classifier. Due to growing large volumes …


Dynamic Physarum Solver: A Bio-Inspired Shortest Path Method Of Dynamically Changing Graphs, Hi̇lal Arslan Jan 2019

Dynamic Physarum Solver: A Bio-Inspired Shortest Path Method Of Dynamically Changing Graphs, Hi̇lal Arslan

Turkish Journal of Electrical Engineering and Computer Sciences

In dynamic graphs, edge weights of the graph change with time and solving the shortest path problem in such graphs is an important real-world problem. The studies in the literature require excessive computational time for computing the dynamic shortest path since determining changing edge weights is difficult especially when the graph size becomes large. In this paper, we propose a dynamic bio-inspired algorithm for finding the dynamic shortest path for large graphs based on Physarum Solver, which is a shortest path algorithm for static graphs. The proposed method is evaluated using three different large graph models representing diverse real-life applications. …


Classification Of The Likelihood Of Colon Cancer With Machine Learning Techniques Using Ftir Signals Obtained From Plasma, Suat Toraman, Mustafa Gi̇rgi̇n, Bi̇lal Üstündağ, İbrahi̇m Türkoğlu Jan 2019

Classification Of The Likelihood Of Colon Cancer With Machine Learning Techniques Using Ftir Signals Obtained From Plasma, Suat Toraman, Mustafa Gi̇rgi̇n, Bi̇lal Üstündağ, İbrahi̇m Türkoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Colon cancer is one of the major causes of human mortality worldwide and the same can be said for Turkey. Various methods are used for the determination of cancer. One of these methods is Fourier transform infrared (FTIR) spectroscopy, which has the ability to reveal biochemical changes. The most common features used to distinguish patients with cancer and healthy subjects are peak densities, peak height ratios, and peak area ratios. The greatest challenge of studies conducted to distinguish cancer patients from healthy subjects using FTIR signals is that the signals of cancer patients and healthy subjects are similar. In the …


Hybrid Parliamentary Optimization And Big Bang-Big Crunch Algorithm For Global Optimization, Soner Kiziloluk, Ahmet Bedri̇ Özer Jan 2019

Hybrid Parliamentary Optimization And Big Bang-Big Crunch Algorithm For Global Optimization, Soner Kiziloluk, Ahmet Bedri̇ Özer

Turkish Journal of Electrical Engineering and Computer Sciences

Researchers have developed different metaheuristic algorithms to solve various optimization problems. The efficiency of a metaheuristic algorithm depends on the balance between exploration and exploitation. This paper presents the hybrid parliamentary optimization and big bang-big crunch (HPO-BBBC) algorithm, which is a combination of the parliamentary optimization algorithm (POA) and the big bang-big crunch (BB-BC) optimization algorithm. The intragroup competition phase of the POA is a process that searches for potential points in the search space, thereby providing an exploration mechanism. By contrast, the BB-BC algorithm has an effective exploitation mechanism. In the proposed method, steps of the BB-BC algorithm are …


Performance Comparison Of Optimization Algorithms In Lqr Controller Design For A Nonlinear System, Ümi̇t Önen, Abdullah Çakan, İlhan İlhan Jan 2019

Performance Comparison Of Optimization Algorithms In Lqr Controller Design For A Nonlinear System, Ümi̇t Önen, Abdullah Çakan, İlhan İlhan

Turkish Journal of Electrical Engineering and Computer Sciences

The development and improvement of control techniques has attracted many researchers for many years. Especially in the controller design of complex and nonlinear systems, various methods have been proposed to determine the ideal control parameters. One of the most common and effective of these methods is determining the controller parameters with optimization algorithms.In this study, LQR controller design was implemented for position control of the double inverted pendulum system on a cart. First of all, the equations of motion of the inverted pendulum system were obtained by using Lagrange formulation. These equations were linearized by Taylor series expansion around the …


Lie Group Analysis For Initial And Boundary Value Problem Of Time-Fractional Nonlinear Generalized Kdv Partial Differential Equation, Doğan Kaya, Gulistan Iskandarova Jan 2019

Lie Group Analysis For Initial And Boundary Value Problem Of Time-Fractional Nonlinear Generalized Kdv Partial Differential Equation, Doğan Kaya, Gulistan Iskandarova

Turkish Journal of Mathematics

The Lie group analysis or in other word the symmetry analysis method is extended to deal with a time-fractional order derivative nonlinear generalized KdV equation. Our research in this work aims to use transformation methods and their analysis to search for exact solutions to the nonlinear generalized KdV differential equation. It is shown that this equation can be reduced to an equation with Erdelyi-Kober fractional derivative. In this study, we research the initial and boundary conditions, considering them invariant, and so we get two ordinary initial value problems, i.e. two Cauchy problems. Conservation laws for the given equation are also …


On Distribution Of Upper Marginal Records In Bivariate Random Sequences, Gülder Kemalbay, İsmi̇han Bayramoğlu Jan 2019

On Distribution Of Upper Marginal Records In Bivariate Random Sequences, Gülder Kemalbay, İsmi̇han Bayramoğlu

Turkish Journal of Mathematics

The theory of record values has been extensively studied in the statistical literature. However, there are not many papers devoted to the theory of records for bivariate and multivariate random sequences. This paper presents the marginal record values and record times in extended sequence of bivariate random vectors. The joint distributions of some upper marginal records are derived. Some results on joint probability mass function of upper record time vectors and distribution function of upper record value vectors are given via copula functions. Moreover, the numerical and graphical applications of considered upper records using flood data and prediction of rainfall …


On A New Generalization Of Telephone Numbers, Urszula Bednarz, Ma?Gorzata Wo?Owiec-Musia? Jan 2019

On A New Generalization Of Telephone Numbers, Urszula Bednarz, Ma?Gorzata Wo?Owiec-Musia?

Turkish Journal of Mathematics

In this paper we introduce a new generalization of telephone numbers. We give the generating function, direct formulae, and matrix generators for these numbers. Moreover, we present their interpretations and we prove some properties of these numbers connected with congruences.


On The Solvability Of The Main Boundary Value Problems For A Nonlocal Poisson Equation, Valery Karachik, Abdizhahan Sarsenbi, Batirkhan Turmetov Jan 2019

On The Solvability Of The Main Boundary Value Problems For A Nonlocal Poisson Equation, Valery Karachik, Abdizhahan Sarsenbi, Batirkhan Turmetov

Turkish Journal of Mathematics

Solvability of the main boundary value problems for the nonlocal Poisson equation is studied. Existence and uniqueness theorems for the considered problems are obtained. The necessary and sufficient solvability conditions for all problems are given and integral representations for the solutions are constructed.


Coumarin-Based Benzilmonohydrazone As A New Proton-Sensitive Fluorescence Dye: Synthesis And Investigation Of Photophysical And Acidochromic Properties, Burcu Aydiner Jan 2019

Coumarin-Based Benzilmonohydrazone As A New Proton-Sensitive Fluorescence Dye: Synthesis And Investigation Of Photophysical And Acidochromic Properties, Burcu Aydiner

Turkish Journal of Chemistry

Coumarin-based chromogenic and fluorogenic dye 4 was designed and synthesized. The photophysical properties of 4 were determined in solvents with different polarities. Protonation affinity was determined by adding trifluoroacetic acid (TFA) to a dichloromethane solution of dye 4 utilizing the UV-Vis and fluorescence titration methods. The protonation region was investigated by using the $^{1}$H NMR method. Additionally, DFT and TDDFT studies were performed to support the structural and absorption spectral properties of 4.


Synthesis And Bioactivity Of Sulfide Derivatives Containing 1,3,4-Oxadiazole And Pyridine, Gang Yu, Shunhong Chen, Feng He, Dexia Luo, Yu Zhang, Jian Wu Jan 2019

Synthesis And Bioactivity Of Sulfide Derivatives Containing 1,3,4-Oxadiazole And Pyridine, Gang Yu, Shunhong Chen, Feng He, Dexia Luo, Yu Zhang, Jian Wu

Turkish Journal of Chemistry

A series of novel sulfide derivatives containing 1,3,4-oxadiazole and pyridine were synthesized, characterized, and tested for their antibacterial activity against tobacco bacterial wilt and rice bacterial blight and for insecticidal activity toward diamondback moth. The results showed that some compounds had good insecticidal and bactericidal activity, e.g., the activities of compounds 6e and 6g-6j toward tobacco bacterial wilt were much better than those of commercial thiodiazole-copper, and some of the synthesized compounds possessed good insecticidal activity against Plutella xylostella. Compounds 6d, 6h, 6j, 6l, 6p, 6r, and 6p displayed over 93% activity at 500 mg L$^{-1}$.


On The Azo Dyes Derived From Benzoic And Cinnamic Acids Used As Photosensitizers In Dye-Sensitized Solar Cells, Luka Matovic, Nikola Tasic, Nemanja Trisovic, Jelena Ladarevic, Vesna Vitnik, Zeljko Vitnik, Branimir Grgur, Dusan Mijin Jan 2019

On The Azo Dyes Derived From Benzoic And Cinnamic Acids Used As Photosensitizers In Dye-Sensitized Solar Cells, Luka Matovic, Nikola Tasic, Nemanja Trisovic, Jelena Ladarevic, Vesna Vitnik, Zeljko Vitnik, Branimir Grgur, Dusan Mijin

Turkish Journal of Chemistry

In order to get a better insight into the relationship between molecular structure and photovoltaic performance, six monoazo dye molecules containing benzoic and cinnamic acid moieties were synthesized and their photovoltaic properties were studied. Three of them have not been previously used in solar cells. Spectroscopic measurements of the investigated compounds coupled with theoretical calculations were performed. Short-circuit current density, open-circuit voltage, and fill-factor were determined. It was found that a larger amount of short-circuit current density will be generated if the HOMO--LUMO energy gap is lower, determined by the stability of the molecule and the electronic effect of the …


Detection Of Lard Contamination In Five Different Edible Oils By Ft-Ir Spectroscopy Using A Partial Least Squares Calibration Model, Fazeelah Munir, Syed Ghulam Musharraf, Syed Tufail Hussain Sherazi, Muhammad Imran Malik, Muhmmad Iqbal Bhanger Jan 2019

Detection Of Lard Contamination In Five Different Edible Oils By Ft-Ir Spectroscopy Using A Partial Least Squares Calibration Model, Fazeelah Munir, Syed Ghulam Musharraf, Syed Tufail Hussain Sherazi, Muhammad Imran Malik, Muhmmad Iqbal Bhanger

Turkish Journal of Chemistry

Lard is defined as animal fat acquired from the adipose tissue of pigs and is not permitted for human consumption or external use by certain religions such as Islam and Judaism. Due to its low-cost availability for commercial use, it is often mixed with other vegetable oils mistakenly or deliberately and causes loss of consumer trust; hence, its detection in food products is essential. Consumers tend to know the authenticity of commercially available edible oils. However, edible oils are subjected to adulteration risks with lard, which breaches consumer rights. In the present study, we designed a transmission Fourier transform infrared …


Mwcnts-Fe$_{2}$O$_{3}$ Nanoparticle Nanohybrid-Based Highly Sensitive Electrochemical Sensor For The Detection Of Kaempferol In Broccoli Samples, Nomnotho Jiyane, Myalowenkosi I. Sabela, Suvardhan Kanchi, Phumlane S. Mdluli, Mavis Xhakaza, Olayide A. Arodola, Krishna Bisetty Jan 2019

Mwcnts-Fe$_{2}$O$_{3}$ Nanoparticle Nanohybrid-Based Highly Sensitive Electrochemical Sensor For The Detection Of Kaempferol In Broccoli Samples, Nomnotho Jiyane, Myalowenkosi I. Sabela, Suvardhan Kanchi, Phumlane S. Mdluli, Mavis Xhakaza, Olayide A. Arodola, Krishna Bisetty

Turkish Journal of Chemistry

This work reports an electrochemical sensor with a modified glassy carbon electrode for the detection of kaempferol. The method was tailored by the immobilization of multiwalled carbon nanotubes (MWCNTs) assimilated with Fe$_{2}$O$_{3}$ nanoparticles (NPs) onto the electrode surface to detect kaempferol using differential pulse voltammetry. Thermogravimetric, transmission electron microscopic, cyclic, and differential voltammetric techniques were employed to characterize the developed electrochemical sensor. The kaempferol produces an anodic quasireversible peak at pH 6.6 in phosphate buffer with Fe$_{2}$O$_{3}$NPs/MWCNTs/GCE. The current of the anodic peak at 0.32 V increases linearly upon addition of kaempferol standard, resulting in Ip($\mu $A) = 1.577($\mu $M) …


Silylation Of Epoxidized Soybean Oil With Triethoxysilanes, Synthesis And Characterization Of Their Polyurethanes, Aynur Özşeker, Kemal Karadeni̇z, Mustafa Yasi̇n Şen Jan 2019

Silylation Of Epoxidized Soybean Oil With Triethoxysilanes, Synthesis And Characterization Of Their Polyurethanes, Aynur Özşeker, Kemal Karadeni̇z, Mustafa Yasi̇n Şen

Turkish Journal of Chemistry

Silylation of epoxidized soybean oil (ESBO) was carried out by epoxy ring opening reaction of methoxy and ethoxy silane compounds. $^{1}$H NMR and FTIR spectra confirmed that two novel bio-based polyols, PSiTh and PSiAm, were obtained through the ring opening of epoxy by the mercapto and amino moieties of MPTMS and APTES, respectively. Polyurethanes of these polyols were prepared using 4,4'- methylene-bis(phenyl isocyanate) (MDI) to incorporate silanol groups into polymer network and were labeled as PUSiTh and PUSiAm, respectively. To see the impact of silanol and phosphorous groups on flame retardant properties, the chain extended polyurethanes, PUSiThCE and PUSiAmCE were …


Ann-Assisted Forecasting Of Adsorption Efficiency To Remove Heavy Metals, Magdi Buaisha, Şazi̇ye Balku, Şeni̇z Özalp Yaman Jan 2019

Ann-Assisted Forecasting Of Adsorption Efficiency To Remove Heavy Metals, Magdi Buaisha, Şazi̇ye Balku, Şeni̇z Özalp Yaman

Turkish Journal of Chemistry

In wastewater treatment, scientific and practical models utilizing numerical computational techniques such as artificial neural networks (ANNs) can significantly help to improve the process as a whole through adsorption systems. In the modeling of the adsorption efficiency for heavy metals from wastewater, some kinetic models have been used such as pseudo first-order and second-order. The present work develops an ANN model to forecast the adsorption efficiency of heavy metals such as zinc, nickel, and copper by extracting experimental data from three case studies. To do this, we apply trial-and-error to find the most ideal ANN settings, the efficiency of which …


Evaluation Of The Enrichment And Amplification Effect Of Pentachlorobenzene With Lower Bioconcentration In The Food Chain Before And After Modification, Ruihao Sun, Meijin Du, Yu Li Jan 2019

Evaluation Of The Enrichment And Amplification Effect Of Pentachlorobenzene With Lower Bioconcentration In The Food Chain Before And After Modification, Ruihao Sun, Meijin Du, Yu Li

Turkish Journal of Chemistry

In this paper, in order to construct a 3D quantitative structure--activity relationship (QSAR) model with the chlorobenzene (CB) molecular structure parameter as an independent variable and the octanol-water partition coefficient ($K_{OW})$ as a dependent variable, 9 kinds of CB molecules were used as training sets and 3 kinds of CB molecules were used as test sets. We adopted the QSAR module in the Sybyl-X2.0 software from the Tripos Corporation (USA). The molecular modification of the pentachlorobenzene molecule with low bioconcentration was carried out by combining a three-dimensional contour map and fractional factorial design. The results showed that the toxicity, migration, …


Design, Synthesis, And Antitumor Evaluation Of Novel Methylene Moiety-Tethered Tetrahydroquinoline Derivatives, Esaam Hamied Ahmed Hanashalshahaby, Canan Ünaleroğlu, Ayşe Ak Can, Alp Özgün, Bora Gari̇pcan Jan 2019

Design, Synthesis, And Antitumor Evaluation Of Novel Methylene Moiety-Tethered Tetrahydroquinoline Derivatives, Esaam Hamied Ahmed Hanashalshahaby, Canan Ünaleroğlu, Ayşe Ak Can, Alp Özgün, Bora Gari̇pcan

Turkish Journal of Chemistry

Novel methylene-tethered tetrahydroquinolines (THQs) and cyclopenta[$b$]pyridines were synthesized by one-pot multicomponent reactions of Mannich bases, enolizable ketones, and NH$_{4}$OAc in water by an environmentally friendly K-10 montmorillonite clay-catalyzed reaction. The cytotoxic activities of 1-(2-methyl-8-methylene-5,6,7,8-tetrahydroquinolin-3-yl)ethanone (9a), ethyl 2-methyl-8-methylene-5,6,7,8-tetrahydroquinoline-3 carboxylate (9b), and 1-(2-methyl-7-methylene-6,7-dihydro-5$H$-cyclopenta[$b$]pyridin-3-yl)ethanone (11a) were tested against rat glioblastoma (C6), human breast cancer (MCF-7), prostate cancer (PC3), neuroblastoma (SH-SY5Y), and mouse fibroblast (L929) cell lines in a concentration-dependent (50-300 μM) and time-dependent (24-72 h) manner and expressed as IC$_{50\, }$values. The results showed that compound 9a induced the lowest IC$_{50\, }$values in all cell lines ranging from 111 ± 1.1 μM to …


Surface Modification Of Polyvinyl Chloride By Polyacrylic Acid Graftas A Polyelectrolyte Membrane Using Ar Plasma, Alaa Fahmy, Mouhamed Abu-Saied, Nasser Morgan, Walid Qutop, Hassan Abdelbary, Tarek Salama Jan 2019

Surface Modification Of Polyvinyl Chloride By Polyacrylic Acid Graftas A Polyelectrolyte Membrane Using Ar Plasma, Alaa Fahmy, Mouhamed Abu-Saied, Nasser Morgan, Walid Qutop, Hassan Abdelbary, Tarek Salama

Turkish Journal of Chemistry

This work reports the synthesis and properties of a new membrane based on polyvinyl chloride (PVC) grafting with polyacrylic acid (PAA) using argon (Ar) plasma. The membranes of PVC were synthesized by solution-casting method, where PAA was deposited as an ultrathin film onto PVC using dielectric barrier discharge at atmospheric pressure with Ar gas. The surface characteristics and chemical composition of the modified membranes were analyzed by water contact angle, scanning electron microscopy, and Fourier transform infrared spectroscopy. Moreover, the electrochemical properties of the membrane were investigated via ion exchange capacity for the purpose of using it as a polyelectrolyte …


Aqueous Two-Phase Extraction Technique Based On Magnetic Ionic Liquid-Nonionic Surfactant For Phenolic Acids In Grape, Apple, Pear, And Banana, Taşkin Mumcu, Serap Seyhan Bozkurt Jan 2019

Aqueous Two-Phase Extraction Technique Based On Magnetic Ionic Liquid-Nonionic Surfactant For Phenolic Acids In Grape, Apple, Pear, And Banana, Taşkin Mumcu, Serap Seyhan Bozkurt

Turkish Journal of Chemistry

An aqueous two-phase extraction system was constituted using magnetic ionic liquid-nonionic surfactant for phenolic acids and the developed method was applied to apple, grape, pear, and banana samples. Ionic liquids based on imidazolium containing butyl, allyl, and benzyl groups were used for extraction. The parameters influencing the extraction efficiency such as volume of ionic liquids, type and amount of surfactant and salt, ultrasound extraction time, temperature, and sample pH were optimized. The extraction efficiencies of ionic liquids were compared for phenolic acids under optimized conditions. Limits of detection and limits of quantification were in the range of 1.34-1.56 μg L$^{-1\, …


An Ultrasensitive Electrochemical Immunosensor Platform Based On Disposable Ito Electrode Modified By 3-Cptms For Early Detection Of Parathyroid Hormone, İnci̇ Uludağ, Mustafa Kemal Sezgi̇ntürk Jan 2019

An Ultrasensitive Electrochemical Immunosensor Platform Based On Disposable Ito Electrode Modified By 3-Cptms For Early Detection Of Parathyroid Hormone, İnci̇ Uludağ, Mustafa Kemal Sezgi̇ntürk

Turkish Journal of Chemistry

Parathyroid hormone (PTH) is a polypeptide containing 84 amino acids secreted by cells of the parathyroid glands. Imbalances of parathyroid levels cause medical problems such as osteoporosis, mental disorders, pancreatitis, kidney stones, cancer, and other symptoms. In this study, we aimed to design an ultrasensitive electrochemical immunosensor for PTH detection. Indium tin oxide (ITO) was used as an electrode for electrochemical impedance spectroscopy (EIS) measurements. ITO sheets were modified by using 3-cyanopropyltrimethoxysilane (3-CPTMS) self-assembled monolayers (SAMs) for immobilizing the anti-PTH antibody via covalent interactions. Cyclic voltammetry (CV) and EIS methods were applied to characterize immobilization steps. Therefore, 1% was selected …


Why Protein Conformers In Molecular Dynamics Simulations Differ From Their Crystal Structures: A Thermodynamic Insight, Fi̇li̇ppo Pullara, Mao Wenzhi, Mert Gür Jan 2019

Why Protein Conformers In Molecular Dynamics Simulations Differ From Their Crystal Structures: A Thermodynamic Insight, Fi̇li̇ppo Pullara, Mao Wenzhi, Mert Gür

Turkish Journal of Chemistry

Conformers generally deviate structurally from their starting X-ray crystal structures early in molecular dynamics (MD) simulations. Studies have recognized such structural differences and attempted to provide an explanation for and justify the necessity of MD equilibrations. However, a detailed explanation based on fundamental physics and validation on a large ensemble of protein structures is still missing. Here we provide the first thermodynamic insights into the radically different thermodynamic conditions of crystallization solutions and conventional MD simulations. Crystallization solution conditions can lead to nonphysiologically high ion concentrations, low temperatures, and crystal packing with strong specific protein--protein interactions, not present under physiological …


Removal Of Cr(Vi) From Wastewater Through Glycine Assisted Synthesis Of Tio$_{2}$, Bi̇lsen Kurtteki̇n, Demet Özer, Nurşen Altuntaş Öztaş Jan 2019

Removal Of Cr(Vi) From Wastewater Through Glycine Assisted Synthesis Of Tio$_{2}$, Bi̇lsen Kurtteki̇n, Demet Özer, Nurşen Altuntaş Öztaş

Turkish Journal of Chemistry

In this study, titanium dioxide was synthesized via solution combustion method. Titanium(IV) oxysulfate was used as a titanium source. The fuel type, reaction time, and reaction temperature were tested for optimization. The glycine was set as a suitable fuel. Structural properties of the final product were characterized by p-XRD. Scanning electron microscopy (SEM) and BET techniques were used to examine the morphology. The synthesized products were compared to the commercial TiO$_{2}$ and it was found that the titanium dioxide with the high surface area (63.628 m$^{2}$/g) has been successfully synthesized by solution combustion method with time and energy saving. In …


Synthesis And Antimicrobial Activity Of 1-(Benzo[B]Thiophen-4-Yl)-4-(2-(Oxo, Hydroxyl, And Fluoro)-2-Phenylethyl)Piperazine And 1-(Benzo[D]Isothiazole-3-Yl)-4-(2-(Oxo, Hydroxy, And Fluoro)-2-Phenylethyl)Piperazine Derivatives, Vaibhav Mishra, Tejpal Singh Chundawat Jan 2019

Synthesis And Antimicrobial Activity Of 1-(Benzo[B]Thiophen-4-Yl)-4-(2-(Oxo, Hydroxyl, And Fluoro)-2-Phenylethyl)Piperazine And 1-(Benzo[D]Isothiazole-3-Yl)-4-(2-(Oxo, Hydroxy, And Fluoro)-2-Phenylethyl)Piperazine Derivatives, Vaibhav Mishra, Tejpal Singh Chundawat

Turkish Journal of Chemistry

Twenty-two compounds in a series of 1-(benzo[$b$]thiophen-4-yl)-4-(2-(oxo, hydroxy, and fluoro)-2-phenylethyl) piperazine and 1-(benzo[$d$]isothiazole-3-yl)-4-(2-(oxo, hydroxy, and fluoro)-2-phenylethyl)-piperazine derivatives were synthesized through nucleophilic substitution reaction of phenacyl bromides with hetero arylpiperazine, reduction, and then fluorination. Compound K2 showed potent activity against gram-negative bacterial stain P. aeruginosa with minimum inhibitory concentration (MIC) value of 12.5 μg/mL. This compound showed better inhibitory activity than the standard drug chloramphenicol. K4 against S. aureus, H2 against P. aeruginosa, and F4 against E. coli showed good inhibitory activity with MIC values of 62.5 μg/mL. Compounds K1, K2, K4, K8, F1, and F3 showed good inhibitory activity against …


Comparative Study On Physicochemical And Mechanical Characterization Of New Nanocarbon-Based Hydroxyapatite Nanocomposites, Reka Barabas, Dennis Deemter, Gabriel Katona, Gabriel Batin, Laszlo Barabas, Liliana Bizo, Oana Cadar Jan 2019

Comparative Study On Physicochemical And Mechanical Characterization Of New Nanocarbon-Based Hydroxyapatite Nanocomposites, Reka Barabas, Dennis Deemter, Gabriel Katona, Gabriel Batin, Laszlo Barabas, Liliana Bizo, Oana Cadar

Turkish Journal of Chemistry

This study evaluated the effect of different additives such as nanocarbon compounds (0.5, 1.0, and 2.0 wt.%) with different morphologies and gelatin (Gel) (10 wt.%) on the mechanical properties of hydroxyapatite (Hap)-based nanocomposites (NCs). The NCs were prepared using the innovation process "SmartBox" based on the Internet of things (IoT), which provides process control and reproducibility, and they were characterized by X-ray diffraction, particle size distribution, transmission electron microscopy, Fourier transform infrared spectroscopy, and thermal analysis. The compressive strength tests demonstrated that the use of grapheme oxide (Hap_ GO_ 2.0 - 133 N/mm$^{2})$, and/or Gel (Hap_ Gel - 152 N/mm$^{2})$ …