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Article Citation - WoS: 18Citation - Scopus: 19Effect of Furan, Thiophene and Selenophene Donor Groups on Benzoselenadiazole Based Donor-Acceptor Systems(Elsevier Science Sa, 2016) Karabay, Lutfiye Canan; Karabay, Bads; Karakoy, Merve Serife; Cihaner, AtillaA series of the monomers called 4,7-di(furan-2-yl)benzo[c][1,2,5]selenadiazole (OSeO), 4,7-di(thiophen-2-yl)benzo[c]11,2,5]selenadiazole (SSeS) and 4,7-di(selenophen-2-yl)benzo[c][1,2,5]selenadiazole (SeSeSe) was synthesized via a donor-acceptor-donor (D-A-D) approach. Benzoselenadiazole was used as an acceptor unit and furan, thiophene and selenophene were used as donor units. The effects of chalcogen atoms (0, S, and Se) in furan, thiophene and selenophene were investigated systematically on the properties of the monomers and their corresponding polymers (POSeO, PSSeS and PSeSeSe, respectively), which were polymerized electrochemically via potentiodynamic or potentiostatic methods. The monomers OSeO, SSeS and SeSeSe exhibited low oxidation potentials of 1.15, 1.25 and 1.19 V vs. Ag/AgCl, respectively. Intramolecular charge transfer interaction between donor and acceptor units was demonstrated from the emission spectra of the monomers. Also, the optical studies showed that the ambipolar and electrochromic polymers POSeO, PSSeS and PSeSeSe have low band gaps of 1.57, 1.47 and 1.45 eV, respectively. (C) 2016 Elsevier B.V. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 52-D Digital Filter Realization Without Overflow Oscillations(Pergamon-elsevier Science Ltd, 2013) Singh, VimalA novel criterion for the elimination of overflow oscillations in 2-D state-space digital filters described by the Roesser model employing two's complement overflow arithmetic is presented. The criterion takes the form of linear matrix inequality (LMI) and, hence, is computationally tractable. The criterion is a generalization and improvement over an earlier criterion. An example shows the effectiveness of the new criterion. (C) 2012 Elsevier Ltd. All rights reserved.Article Citation - WoS: 15Citation - Scopus: 21A Short Note on c*-valued Contraction Mappings(Springeropen, 2016) Alsulami, Hamed H.; Agarwal, Ravi P.; Karapinar, Erdal; Khojasteh, FarshidIn this short note we point out that the recently announced notion, the C*-valued metric, does not bring about a real extension in metric fixed point theory. Besides, fixed point results in the C*-valued metric can be derived from the desired Banach mapping principle and its famous consecutive theorems.Article Citation - WoS: 27Citation - Scopus: 42Properties of the Laplace transform on time scales with arbitrary graininess(Taylor & Francis Ltd, 2011) Bohner, Martin; Guseinov, Gusein Sh.; Karpuz, Basak; Karpuzc, BaşakWe generalize several standard properties of the usual Laplace transform to the Laplace transform on arbitrary time scales. Some of these properties were justified earlier under certain restrictions on the graininess of the time scale. In this work, we have no restrictions on the graininess.Article Citation - WoS: 14Dissociative Adsorption of Water at (211) Stepped Metallic Surfaces by First-Principles Simulations(Amer Chemical Soc, 2017) Pekoz, Rengin; Donadio, DavideSteps at high-index metallic surfaces display higher chemical reactivity than close-packed surfaces and may give rise to selective adsorption and partial dissociation of water. Inspired by differential desorption experiments, we have studied the adsorption and dissociation of water clusters and one-dimensional wires on Pt(211) by density functional theory and molecular dynamics simulations. These calculations reveal that water at the step edges of Pt(211) adsorbs more weakly than at Pt(221), but partial dissociation of adsorbed water clusters is energetically competitive. We observe that the one-dimensional structure proposed experimentally can be realized only by partially dissociated water wires. In addition, weaker adsorption allows the formation of structures in which a number of water molecules detach from the step and form weak hydrogen bonds with the terrace. This study is further extended to the energetics of small water clusters on (211) surfaces of Ir, Rh, and Pd.Article Citation - WoS: 25Citation - Scopus: 31Best proximity points and extension of Mizoguchi-Takahashi's fixed point theorems(Springer int Publ Ag, 2013) Kumam, Poom; Aydi, Hassen; Karapinar, Erdal; Sintunavarat, WutipholIn this paper, we introduce a multi-valued cyclic generalized contraction by extending the Mizoguchi and Takahashi's contraction for non-self mappings. We also establish a best proximity point for such type contraction mappings in the context of metric spaces. Later, we characterize this result to investigate the existence of best proximity point theorems in uniformly convex Banach spaces. We state some illustrative examples to support our main theorems. Our results extend, improve and enrich some celebrated results in the literature, such as Nadler's fixed point theorem, Mizoguchi and Takahashi's fixed point theorem.Article Citation - WoS: 9Citation - Scopus: 10Impact of Hospital-Acquired Acute Kidney Injury on Covid-19 Outcomes in Patients With and Without Chronic Kidney Disease: a Multicenter Retrospective Cohort Study(Tubitak Scientific & Technological Research Council Turkey, 2021) Ozturk, Savas; Turgutalp, Kenan; Arıcı, Mustafa; Çetinkaya, Hakkı; Altıparmak, Mehmet Rıza; Aydın, Zeki; Ateş, Kenan; Dolarslan, Mursıde Esra; Seyahi, Nurhan; Yıldız, Alaattın; Bora, FeyzaBackground/aim: Hospital-acquired acute kidney injury (HA-AKI) may commonly develop in Covid-19 patients and is expected to have higher mortality. There is little comparative data investigating the effect of HA-AKI on mortality of chronic kidney disease (CKD) patients and a control group of general population suffering from Covid-19. Materials and methods: HA-AKI development was assessed in a group of stage 3–5 CKD patients and control group without CKD among adult patients hospitalized for Covid-19. The role of AKI development on the outcome (in-hospital mortality and admission to the intensive care unit [ICU]) of patients with and without CKD was compared. Results: Among 621 hospitalized patients (age 60 [IQR: 47–73]), women: 44.1%), AKI developed in 32.5% of the patients, as stage 1 in 84.2%, stage 2 in 8.4%, and stage 3 in 7.4%. AKI developed in 48.0 % of CKD patients, whereas it developed in 17.6% of patients without CKD. CKD patients with HA-AKI had the highest mortality rate of 41.1% compared to 14.3% of patients with HA-AKI but no CKD (p < 0.001). However, patients with AKI+non-CKD had similar rates of ICU admission, mechanical ventilation, and death rate to patients with CKD without AKI. Adjusted mortality risks of the AKI+non-CKD group (HR: 9.0, 95% CI: 1.9–44.2) and AKI+CKD group (HR: 7.9, 95% CI: 1.9–33.3) were significantly higher than that of the non-AKI+non-CKD group. Conclusion: AKI frequently develops in hospitalized patients due to Covid-19 and is associated with high mortality. HA-AKI has worse outcomes whether it develops in patients with or without CKD, but the worst outcome was seen in AKI+CKD patients.Key words: Acute kidney injury, chronic kidney disease, Covid-19, hospitalization, mortalityArticle Citation - WoS: 13Citation - Scopus: 13Comparison of Physicochemical Properties of Two Types of Polyepichlorohydrin-Based Anion Exchange Membranes for Reverse Electrodialysis(Mdpi, 2022) Karakoc, Ezgi; Guler, EnverThe development of the most effective, suitable and economic ion-exchange membranes is crucial for reverse electrodialysis (RED)-the most widely studied process to harvest salinity gradient energy from mixing seawater and river water. RED utilizes two types of membranes as core elements, namely cation exchange membranes (CEM) and anion exchange membranes (AEM). Since the preparation of AEMs is more complex compared to CEMs, the design and development of anion exchange membranes have been the focus in this study. Homogeneous AEMs based on two types of polyepichlorohydrin (PECH) with different chlorine amounts (PECH-H, 37 wt% and PECH-C, 25 wt%) were synthesized, and first-time benchmarking of the membrane properties was conducted. In addition to physicochemical membrane properties, some instrumental analyses such as SEM, FTIR and DSC were investigated to characterize these anion-exchange membranes. Based on the results, although the PECH-H-type membrane had enhanced ion-exchange properties, PECH-C-based anion-exchange membranes exhibited a higher power density of 0.316 W/m(2) in a lab-scale RED system. Evidently, there is room for the development of new types of PECH-C-based AEMs with great potential for energy generation in the RED process.Letter Reply to An Investigation Into the Serum Thioredoxin, Superoxide Dismutase, Malondialdehyde, and Advanced Oxidation Protein Products for Patients with Breast Cancer(Springer, 2017) Kilic, Nedret[No Abstract Available]Article Citation - Scopus: 3Coincidence Points for Expansive Mappings Under C-Distance in Cone Metric Spaces(2012) Aydi,H.; Karapinar,E.; Moradi,S.We establish some fixed (common fixed) and coincidence point results for mappings verifying some expansive type contractions in cone metric spaces with the help of the concept of a c-distance. Our results generalize, extend, and unify several well-known comparable results in the literature. Some examples are also presented. Copyright © 2012 Hassen Aydi et al.
