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  Subjects -> SCIENCES: COMPREHENSIVE WORKS (Total: 374 journals)
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Adıyaman University Journal of Science
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Print) 2147-1630 - ISSN (Online) 2146-586X
Published by Adıyaman Üniversitesi Homepage  [3 journals]
  • The Effective and Eco-friendly Tea Fungus for the Biosorption of Dye
           Pollutant from Aqueous Solutions

    • Authors: Tuğba ALP ARICI
      Abstract: The present study has reported the production of the environmentally friendly Kombucha tea fungus (TF), as well as its investigation as a potential biosorbent to remove cationic methyl violet (MV) dye from the aqueous solutions. TF was characterized by using FT-IR, thermal analysis and zeta potential measurements. The biosorption of MV was significantly dependent on the pH of the solutions and the highest removal for MV was observed at pH=9.0 which was also proved with zeta potential measurement. Biosorption equilibrium was established in 10 min and a definition of the overall rate-controlling step in the biosorption of MV onto TF was carried out. The biosorption data were in good agreement with the pseudo-second-order kinetic and Langmuir isotherm models. The maximum biosorption capacity of TF for MV was determined as 1180.09 mg g−1. In addition, an effective biosorption performance was observed even in the presence of high foreign ion concentrations. The results indicated that TF could be utilized as a highly efficient biosorbent for MV biosorption from aqueous solutions.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Prediction of Human Development Index with Health Indicators Using
           Tree-Based Regression Models

    • Authors: Pelin AKIN; Tuba KOC
      Abstract: Machine learning is a field of artificial intelligence that allows computers to predict and model future events by making inferences from past information with mathematical and statistical operations. In this study, we used tree-based regression models, one of the machine learning methods, to determine and predict the effect of health indicators of 191 countries on the human development index (HDI) between 2014 and 2018 years. When tree-based regression models were compared according to model performance criteria, it was found that the best model was the gradient boosting model with the highest R2 = 0.9962 and the smallest RMSE = 0.0094. With the gradient boosting model, the three most important variables to HDI are; current health expenditure per capita, physicians and nurses, and midwives, respectively. By selecting the ten countries with the highest HDI values and Turkey, HDI values were estimated for 2018-2019 with a gradient boosting model. The countries for which HDI values are best predicted by the gradient boosting method are Netherlands, Sweden, Norway, Iceland, Denmark, Turkey, Ireland, Germany, Australia, and China.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Comparatively Investigation of Textile Dye Decolorization by a White Rot
           Fungus and Various Bacterial Strains

    • Authors: Emre BİRHANLI; Özfer YEŞİLADA, Doç. Dr. Ahmet ÇABUK, Filiz BORAN, Eray TATLICI
      Abstract: The aim of this study is to comparatively investigate the decolorization of Reactive Blue 171 (RB 171) by using three different bacterial strains as Bacillus megaterium A1 (A1), Gordonia sp. MC-D1 (D1) and Bacillus pumilus D3 (D3) and also a white rot fungus (Pleurotus ostreatus). All tested bacteria were incubated with RB 171 dye at 150 mg/L concentration for 24-72 h under static or agitated (150 rpm) conditions while the fungus was incubated with 150 mg/L of the dye under the same conditions for 3-24 h. The highest bacterial decolorization values were obtained after 72 h of incubation under static conditions and the maximum decolorization rates were detected as 84, 83 and 75% for A1, D1 and D3, respectively. However, the color of RB 171 dye was removed at 93% rate by Pleurotus ostreatus under static conditions after 24 h of incubation. Similar results were also obtained from the agitated studies of the tested fungal and bacterial strains except A1. The maximum decolorization values obtained with A1, D1 and D3 at 150 rpm, 72 h were 30, 88 and 89%, respectively. The highest decolorization activities of Pleurotus ostreatus were 93% for both static and agitated (150 rpm) conditions. In addition, zymogram analyzes of the fungal culture fluids obtained from SBM and SBM containing 150 mg/L RB 171 were also performed to detect the presence of laccase.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • A Comparative Study of DFT/B3LYP/6-31G(d,p), RM062X/6-31G(d,p),
           B3LYP/6-311++G(d,p) and HSEH1PBE/6-31G(d,p) Methods Applied to Molecular
           Geometry and Electronic properties of Cs-C60Cl6 Molecule

    • Authors: Ebru KARAKAŞ SARIKAYA; Ömer DERELİ, Semiha BAHÇELİ
      Abstract: In this study, four different levels, B3LYP/6-31G(d,p), RM062X/6-31G(d,p), B3LYP/6-311++G(d,p) and HSEH1PBE/6-31G(d,p) of the DFT quantum chemical calculation method have been applied to the molecular structure of the Cs-C60Cl6 molecule as a halogenated fullerene. Additionally, the molecular structure of pure C60 fullerene was presented as complementary and supportive work. Furthermore, the simulated FT-IR, Raman and UV-Vis (in cyclohexane solvent) spectra, HOMO-LUMO analysis, the molecular electrostatic potential (MEP) map, the 13C NMR chemical shift values in both gas phase and tetrachloromethane with deuterated chloroform solvent and the thermodynamics properties at the mentioned levels of the Cs-C60Cl6 molecule were reported. Fullerene has many physical and electrochemical properties, which can be utilized in several medical fields. Especially, it can fit inside the hydrophobic cavity of HIV proteases, restricting the get into substrates to the catalytic site of the enzyme. Hence, it is utilizable as an antioxidant and radical scavenger.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Physiological and Molecular Effects of Exogenous Gibberellin (GA3)
           Treatment on Germination of Barley Seeds under Salt Stress

    • Authors: Cüneyt UÇARLI
      Abstract: Salinity is considered as one of the most important factors restricting germination parameters including rate and percentage of seed germination in crops. This study focused on the alleviating role of exogenously applied 10 mg/L gibberellic acid (GA3) on barley (Hordeum vulgare L.) seeds during germination under salt stress (120 mM NaCl). Physiological and morphological changes, and differential gene expression at 3 days after imbibition (DAI) were determined and compared with or without gibberellic acid (GA3) under salt stress. Exogenous GA3 was found to increase the shoot and root length of germinated barley seeds under salt stress by 67 and 15%, respectively, compared to those treated with salinity alone. On the other hand, exogenous GA3 treatment significantly reduced ion leakage, osmolyte accumulation, and proline content under salinity. NaCl was found to decrease the expression of the HvABI5, HvABA7 and HvKO1 by 3, 10, and 33 fold, respectively, at 3 DAI, whereas addition of GA3 in root medium rescued the expression of these genes to control levels. Besides, exogenous GA3 significantly promoted the decreased mRNA level of HvGA2ox2 due to salinity during germination. This study may give insight into the relationship between salinity stress and the genes involved in GA3 metabolism and germination.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Exchange Bias Effect in NiMnSbB Ferromagnetic Shape Memory Alloys
           Depending on Mn Content

    • Authors: Gökhan KIRAT
      Abstract: In this study, exchange bias effect was investigated in boron added NiMnSb Heusler alloys. The samples were fabricated by arc melting method with Ni49Mn37,5Sb13,5+Bx, Ni49Mn37,7Sb13,3+Bx and Ni49Mn37,9Sb13,1+Bx nominal compositions. XRD analyzes showed that the samples were in L21 crystal structure at room temperature. While the martensitic phase transition temperatures increased, the magnetic moment value decreased with the increase in Mn content. The decrease in magnetization is owing to the increase in antiferromagnetic interactions with the increase of Mn content. Under low field and zero field cooling M-T measurements revealed that antiferromagnetic interactions were more dominant at low temperature but ferromagnetic behavior was more effective in the system at high temperature region. The coexistence of ferromagnetism and antiferromagnetism in a magnetic material can cause the exchange bias effect. Therefore, the hysteresis loops were examined at 5 K of the samples cooled under 50 kOe magnetic field. The shift at the origin of the magnetization curve, which is attributed to the exchange bias effect, increased with increasing Mn amount.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • On The Convergence Properties of Kantorovich-Szasz Type Operators
           Involving Tangent Polynomials

    • Authors: Erkan AĞYÜZ
      Abstract: In this paper, we construct a variant of the Kantorovich Szazs type operators involving the Tangent polynomials and estimate convergence properties of these operators by using Korovkin theorem. Also we obtain the rate of convergence by using modulus of convergence and Peteer’s K-functional.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Density Functional Theory Studies of Some Barbiturates on Lipophilicity

    • Authors: Sümeyya SERİN; Ali BAYRİ
      Abstract: This paper deals with the evaluation of lipophilicity expressed by logPow parameter of ten barbiturate derivatives generally used as sedative-hypnotics based on Density Functional Theory (DFT) calculations. All geometry optimizations and frequency calculations have been carried out by using DFT/B3LYP/ 6-311++G (d,p) basis set in gas phase and also in water and n-octanol phases. Gibbs free energies of solvation for studied barbiturates were calculated to predict logPow. The correlation between the calculated logPow values and available data in literature has been examined. Root mean square error (RMSE), mean square error (MSE), mean absolute deviation (MAD) and mean absolute percentage error (MAPE) statistics were utilized in measuring predictive accuracy (forecast performance) of DFT method used in this study. Accordingly, the reasonable results have been obtained in estimating the partition coefficient of the mentioned ten barbiturate derivatives by DFT/B3LYP/6-311++G (d,p) method. The lipophilicity tendency of the studied barbiturates was interpreted with the help of the calculated quantum chemical descriptors such as HOMO energy (EHOMO), LUMO energy (ELUMO), molecular volume (Vm), electrophilicity index (ω). ELUMO, Vm, and ω descriptors gave reasonable results rather than EHOMO. Also, the 3D molecular lipophilicity potential (MLP) maps that display the accumulative lipophilic contributions of each atom in studied barbiturates were visualized.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • On Surfaces in pseudo-Galilean space with prescribed mean curvature

    • Authors: Muhittin Evren AYDIN; Alper Osman ÖĞRENMİŞ
      Abstract: In this work, we consider certain classes of surfaces in the pseudo-Galilean space, the translation and factorable surfaces. We classify these surfaces that satisfy the equation H=v^ , where H is the mean curvature and v^ the normal component of an isotropic vector v.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • A New Approach to Fibonacci Tessarines with Fibonacci and Lucas Number

    • Authors: Faik BABADAĞ; Merve USLU
      Abstract: In this paper, by using identities related to the tessarines, Fibonacci numbers and Lucas numbers we define Fibonacci tessarines and Lucas tessarines. We obtain Binet formulae, D’ocagnes identity and Cassini identity for these tessarines. We also give the identities of Fibonacci negatessarines and Lucas negatessarines and define new vector which are called Fibonacci tessarine vector. 
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Fixed Points for Generalized Type Contractions in Partially Ordered Metric

    • Authors: Seher Sultan YEŞİLKAYA
      Abstract: In this article, we define ordered weakly θ-contractive and ordered Ciric type weakly θ-contractive mappings in partially ordered metric spaces and introduce some fixed point theorems for such mappings. These theorems extend the main theorems of many comparable results from the current literature. Finally, an example is showed to support the new theorems.Bu makalede, kısmi sıralı metrik uzaylarda sıralı zayıf θ-daralma ve sıralı kirik tipi zayıf θ-daralma dönüşümleri tanımlıyoruz ve bu tür dönüşümler için bazı sabit nokta teoremlerini tanıtıyoruz. Bu teoremler, mevcut literatürden birçok karşılaştırılabilir sonucun ana teoremlerini genişletir. Son olarak, yeni teoremleri destekleyen bir örnek gösterildi.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • An Educational Higgs Study with CMS Open Data

    • Authors: Bora AKGUN
      Abstract: The Compact Muon Solenoid (CMS) Experiment is one of the particle detectors at CERN’s Large Hadron Collider (LHC). The CMS Collaboration consists of more than 5000 scientists, engineers, technicians and students from more than 200 institutes and universities from more than 40 countries. The CMS collaboration has a wide physics program and published more than 1000 papers. The CMS has provided open access to 2 PB of its data recorded in proton-proton collisions for research and educational use. This paper gives a brief description on how to analyze the CMS open data and shows a simple Higgs Boson analysis with the data recorded in early 2011. 
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Invariant and Lacunary Invariant Statistical Equivalence of Order β
           for Double Set Sequences

    • Authors: Uğur ULUSU; Erdinç DÜNDAR, Fatih NURAY
      Abstract: In this study, as a new approach to the concept of asymptotical equivalence in the Wijsman sense for double set sequences, the new concepts which are called asymptotical invariant statistical equivalence of order β and asymptotical lacunary invariant statistical equivalence of order β (0<β≤1) in the Wijsman sense for double set sequences are introduced and explained with examples. In addition, the existence of some relations between these concepts and furthermore, the relationships between these concepts and previously studied asymptotical equivalence concepts in the Wijsman sense for double set sequences are investigated.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Optimization Based Undersampling for Imbalanced Classes

    • Authors: Fatih SAĞLAM; Mervenur SÖZEN, Mehmet Ali CENGİZ
      Abstract: The classification methods consider the probability of predicting the majority class to be high when the number of class observations is different. To address this problem, there are some methods such as resampling methods in the literature. Undersampling, one of the resampling methods, creates balance by removing data from the majority class. This study aims to compare different optimization methods to determine the most suitable observations to be taken from the majority class while undersampling. Firstly, a simple simulation study was conducted and graphs were used to analyze the discrepancy between the resampled datasets. Then, different classifier models were constructed for different imbalanced data sets. In these models, random undersampling, undersampling with genetic algorithm, undersampling with differential evolution algorithm, undersampling with an artificial bee colony, and under-sampling with particle herd optimization were compared. The results were given rank numbers differing depending on the classifiers and data sets and a general mean rank was obtained. As a result, when undersampling, artificial bee colony was seen to perform better than other methods of optimization.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Linear Convex Combination Estimators and Comparisons

    • Authors: Selahattin KAÇIRANLAR; Issam DAWOUD, Dünya KARAPINAR
      Abstract: In this paper, we introduce two linear convex combination estimators by using known estimators such as ordinary least squares, ridge and Liu estimators and examine the predictive performance of these estimators. Furthermore, a numerical example is examined to compare these estimators under the prediction mean squared error criterion.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Estimation of Risk Measures for Transmuted Weibull Distribution

    • Authors: Caner TANIŞ
      Abstract: In this paper, we tackle a problem of the estimation of some risk measures for transmuted Weibull distribution. In this regard, the maximum likelihood method is used to estimate the risk measures. We also obtain asymptotic confidence intervals based on the asymptotic distributions of maximum likelihood estimators of risk measures. Then, we consider a comprehensive Monte Carlo simulation study to assess the performances of these estimators at different sample sizes and parameter settings.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Comparison of Prooxidant Activities of Various Fruit Juices and Herbs via
           Gold Nanocluster Biosensors and Carbonyl Assay

    • Authors: Esin AKYÜZ
      Abstract: Under oxidative stress conditions, which are defined as the deterioration of antioxidant and prooxidant balance in the organism in favor of prooxidants, ROS species that trigger the formation of various diseases occur. The fact that these harmful species cause oxidative damage to biological macromolecules is expressed as prooxidant activity. In this study, Cu(II)‒catalyzed prooxidant activities of pomegranate, apricot, peach, and pear juices and extracts of mint, white tea, and rosehip were measured by using gold nanoclusters synthesized via chicken egg white proteins. Fluorometric and spectrophotometric gold nanocluster biosensors and carbonyl assay were used. The fruit juices were used directly by diluting with pure water. Herbal plant samples were extracted in an ultrasonic water bath, filtered through microfilters, and stored in the refrigerator. Total prooxidant activities of fruit juices and herbal plants were calculated in terms of mM epicatechin equivalent, and the results obtained by applying all methods were compared with each other. It has been found that the applied methods can be used to accurately determine the total prooxidant activity of many food products.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Identification of Damaging SNPs and Their Effects on Alzheimer’s
           Disease-Associated PSEN1 Protein: Computational Analysis

    • Authors: Orçun AVŞAR
      Abstract: Alzheimer’s Disease (AD) is a progressive neurodegenerative disease and pathologically characterized by the presence of neurofibrillary tangles (tau aggregation) and amyloid plaques (amyloid-beta (A𝛽) aggregation). PSEN1 protein with 9 transmembrane helices acts as aspartyl protease and is one of the catalytic components of γ secretase complex, that cleaves amyloid precursor protein (APP). Furthermore, PSEN1 protein plays a significant role in the process of APP and in the generation of amyloid beta (Aβ). In the present study, it was aimed to estimate the probable deleterious effects of missense SNPs in PSEN1 gene that is associated with AD on protein stability and structure by using bioinformatics tools. SIFT, PolyPhen-2, PROVEAN, PhD-SNP, and PANTHER PSEP software were used to estimate the deleterious SNPs, whereas I-Mutant 3.0 and MUpro web tools were used to determine the effects of amino acid substitution on protein stability. Additionally, the effects of wild type and mutant amino acids on protein three-dimensional structure via modeling were predicted by Project HOPE webserver. The phylogenetic conservation of amino acid residues of PSEN1 protein was analyzed by ConSurf. In total, 386 missense SNPs were found in the human PSEN1 gene from the National Center for Biotechnology Information Single Nucleotide Polymorphism (NCBI dbSNP) database and 65 SNPs of which were determined to be deleterious or damaging. In the present study, 8 significant missense SNPs- rs63749891 (R278T), rs63750301 (P264L), rs63750353 (N135D), rs63750524 (R278S), rs63750772 (E273A), rs63751229 (P267S), rs121917807 (G266S), and rs201617677 (R157S)- were determined as high-risk pathogenic. Some differences between wild-type amino acids and mutant amino acids such as hydrophobicity, charge, size, and folding properties were determined according to the modeling findings. Our study demonstrates that high-risk pathogenic missense SNPs have the potential to alter the catalytic activity of the γ secretase complex and subsequently the amount of Aβ40 and Aβ42. Therefore, these missense SNPs may contribute to AD pathogenesis studies.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Evaluation of radiation attenuation properties of some cancer drugs

    • Authors: İlyas ÇAĞLAR; Gülçin BİLGİCİ CENGİZ (EKER
      Abstract: The present study was conducted to estimate the radiation attenuation parameters of six different antineoplastic drugs used in the cure of cancer diseases. The effective atomic number and electron density of anastrozole, epirubicin, gemcitabine, ifosfamide, methotrexate and paclitaxel were computed theoretically in the energy region of 1keV to 100 GeV. The energy absorption buildup factors (EABF) and exposure buildup factors (EBF) for these chemotherapy drugs were also examined by applying GP-fitting method. The variation of EABF and EBF values with photon energy and penetration depth were presented graphically and discussed. The results obtain from this study pointed out that buildup factors rely on the chemical combination of the drugs, incident photon energy and penetration thickness. It was observed that ifosfamide had a significantly better radiation absorption effect compared to other drugs. The data obtained from this study are expected to be useful in the fields of radiation biology, radiation dosimetry and radiotherapy.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • Solitary Wave Solutions of the (3+1)-dimensional
           Khokhlov–Zabolotskaya–Kuznetsov Equation by Using the
           (G^'/G,1/G)-Expansion Method

    • Authors: Hülya DURUR; Serbay DURAN, Asıf YOKUŞ
      Abstract: In this study, the (3+1)-dimensional Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, which is a mathematical model of non-absorption and dispersion in the non-linear medium, which sheds light on the sound beam phenomenon, which has a physically important place, is examined. In order to find the exact solution of this equation, an effective and reliable method, (G^'/G,1/G)-expansion method, is used among analytical methods. The purpose of this method is to obtain more than one traveling wave solution classes depending on the conditions of the λ parameter. These classes are categorized into hyperbolic, trigonometric, complex trigonometric and rational forms. The graphics of the solitary waves represented by these successfully obtained solution classes are presented as 2-dimensional, 3-dimensional and contours. This article makes use of ready-made package programs for complex arithmetic operations and graphic drawings.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
  • The Modified Exp (-ϑ(σ))-Expansion Function Method for Exact Solutions
           of the Simplified MCH Equation and the Getmanou Equation

    • Authors: Şeyma TÜLÜCE DEMİRAY; Sevgi KASTAL
      Abstract: The present research explores, the modified exp -expansion function method (MEFM) is tested by applying it to obtain the exact travelling wave solutions for the simplified MCH equation and the Getmanou equation. Dark optical soliton solutions and dark-bright optical soliton solutions of the simplified MCH equation and the Getmanou equation are successfully constructed by using this method. We carry out all the computations and draw the 2D and 3D graph in this paper by Wolfram Mathematica 9. Besides, the graphical representation obviously shows forcefulness of this method.
      PubDate: Fri, 31 Dec 2021 00:00:00 +030
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