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Öğe Electrochemical performance of boron-doped diamond electrode in surfactant-containing media for ambroxol determination(Elsevier, 2014-07-17) Levent, Abdulkadir; Yardım, Yavuz; Şentürk, ZühreA novel application of boron-doped diamond electrode is introduced for the determination of ambroxol, a potential antioxidant drug belonging to the expectorant class. The electrochemical oxidation of ambroxol was first investigated by cyclic voltammetry using boron-doped diamond and glassy carbon electrodes in aqueous solutions both with and without the addition of surfactant. The compound was irreversibly oxidized in one/two steps at high positive potentials, resulting in the formation of a couple with a reduction and re-oxidation wave at less positive potentials. Special attention was given to the use of adsorptive stripping voltammetry at a surface of mildly oxidized boron-doped diamond electrode in aqueous solutions over the pH range of 1.0–10.0. Addition of anionic surfactant (sodium dodecylsulfate) to ambroxol-containing electrolyte enhanced the stripping current signal. Using square-wave stripping mode, the drug yielded a well-defined voltammetric response in phosphate buffer pH 2.5 containing 4 × 10−4 M sodium dodecylsulfate at +1.02 V (versus Ag/AgCl) (after 30 s accumulation at +0.50 V). The process could be used to determine ambroxol in the concentration range of 0.05–0.7 μM, with a detection limit of 0.010 μM (4.2 ng mL−1). The suggested method was successfully applied to pharmaceuticals and spiked human urine samples.Öğe A fuzzy logic based approach to solve interval multiobjective nonlinear transportation problem(Springer Nature, 2019-06-01) Dalman, Hasan; Sivri, MustafaThis paper presents the solution procedure of multiobjective nonlinear transportation problem (MNOTP) where the cost coefficients of the objective functions, and the supply and the unknown demand parameters have been formulated as interval numbers by the decision maker. This problem has been converted into a conventional MNOTP where to minimize the interval nonlinear objective functions, the order relations that define the choice between intervals have been determined by the interval arithmetic. Also, the constraints with interval supply and unknown demand parameters have been transformed into its deterministic forms. Then the deterministic problems have been solved by two compromise programming methods. Finally, a numerical example is presented to illustrate the efficiency of the proposed procedure as well.Öğe Interactive goal programming algorithm with Taylor series and interval type 2 fuzzy numbers(Springer Nature, 2019-06-01) Dalman, Hasan; Bayram, MustafaThis paper presents an interactive fuzzy goal programming (FGP) approach for solving Multiobjective Nonlinear Programming Problems (MONLPP) with interval type 2 fuzzy numbers (IT2 FNs). The cost and time of the objective functions, and the requirements of each kind of resources are taken to be trapezoidal IT2 FNs. Here, the considered fuzzy problem is first transformed into an equivalent crisp MONLPP, and then the MONLPP is converted into an equivalent multiobjective linear programming problem (MOLPP). By using an algorithm based on Taylor series, this problem is also reduced into a single objective linear programming problem (LPP) which can be easily solved by Maple 2017 optimization toolbox. Finally, the proposed solution procedure is illustrated by a numerical example.Öğe Novel C2-symmetric macrocycles bearing diamide-diester groups: Synthesis and enantiomeric recognition for primary alkyl ammonium salts(American Chemical Society, 2008-03-12) Sünkür, Murat; Barış Cebe, Deniz; Hoşgören, Halil; Toğrul, MahmutWe synthesized a series of novel macrocycles with diamide−diester groups (S,S)-1, (S,S)-2, (S,S)-3, and (R,R)-1, derived from dimethyloxalate and amino alcohols by high dilution technique, and evaluated enantiomeric recognition properties of these macrocycles toward primary alkyl ammonium salts by 1H NMR titration. Taking into account the host employed, important differences were observed in the Ka values of (R)-Am and (S)-Am for (S,S)-1 and (R,R)-1 hosts, KS/KR = 5.55 and KR/KS = 3.65, ΔΔGo = 0.43 and −0.32 kJ mol-1, respectively. There seems a general tendency for the host to include the guests with the same absolute configuration.Öğe Do low serum uch-l1 and tdp-43 levels indicate disturbed ubiquitin- proteosome system in autism spectrum disorder?(Türk Nöropsikiyatri Derneği, 2017) Çetin, İhsan; Tezdiğ, İhsan; Tarakçıoğlu, Mahmut Cem; Kadak, Muhammed Tayyib; Demirel, Ömer Faruk; Erdoğan, Fırat; Doğangün, BurakIntroduction: The mechanism of ubiquitination-related abnormalities causing neural development problems is still unclear. We examined the association between autism and serum transactive response DNAbinding protein-43 (TDP-43) and ubiquitin c-terminal hydrolase-L1 (UCH-L1) levels, both of which are members of the ubiquitinproteosome system. Methods: We measured serum levels of TDP-43 and UCH-L1 in 24 children with autism and 24 healthy children. Childhood Autism Rating Scale (CARS) was used to assess symptom severity at admission. Results: The mean serum TDP-43 and UCH-L1 levels in children with autism spectrum disorder (ASD) were found to decrease compared to healthy controls (p<0.001, 506.21±780.97 ng/L and 1245.80±996.76 ng/L, respectively; 3.08±5.44 ng/mL and 8.64±6.67 ng/mL, respectively). A positive correlation between serum TDP-43 levels and UCH-L1 levels was found in the ASD group (r=0.947, n=24, p<0.001). The CARS score of children with ASD was 48.91 points (standard deviation [SD]: 5.82). Conclusion: Low serum levels of UCH-L1 and TDP-43 may reflect disturbed ubiquitination in autism.Öğe Some new properties of inner product quasilinear spaces(University of Prishtina, 2016-03) Bozkurt, Hacer; Yılmaz, YılmazIn the present paper, we introduce over symmetric set on a inner product quasilinear spaces. We establish some new results related to this new concept. Further, we obtain new conclusions for orthogonal and orthonormal subspaces of inner product quasilinear spaces. These results generalize recent well known results in the linear inner product spaces. Also, some examples have been given which provide an important contribution to understand the structure of inner product quasilinear spaces.
