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Article Citation - WoS: 18Citation - Scopus: 18Metagenomic and Chemical Analysis of Tarhana During Traditional Fermentation Process(Elsevier, 2021) Soyucok, Ali; Yurt, Mediha Nur Zafer; Altunbas, Osman; Ozalp, Veli Cengiz; Sudagidan, MertTarhana is one of the favourable traditional fermented food consumed as a soup. Different flour, vegetables, spices and yogurt are main constituents and they compose of microbiota of Tarhana. In this study, bacterial communities in each fermentation process and in their constituents were identified by metagenomic analysis. Also, chemical properties (pH, acidity, salt content and dry matter) were analysed in each step. The results showed that in the dough formation, mainly Lactobacillus, Bacillus, Enterococcus and Streptococcus were present and after Day 4, Clostridium and Bacillus became dominant, after drying Clostridium disappeared and in the final product bacterial communities from Bacillus and Streptococcus genus were observed. Chemical analysis showed that pH decreased from 4.94 to 4.46, acidity increased by time at the beginning of fermentation from 7.5% to 22.5% in first 6 days period, then, became stable at 14% in drying process. Salt content increased by time from 1.74 to 3.08 g salt/100 g Tarhana in first 8 days and in drying process salt content was recorded as 2.81-2.90 and dry matter was obtained as 94 g dry matter/100 g Tarhana in the final product. This study elucidated the effects of ingredients, raw materials and how microbiota and chemical properties changes during fermentation steps of home-made traditional Tarhana production and thus preparation methods could be developed to obtain standardized Tarhana products for industrial production in future.Article Citation - WoS: 7Citation - Scopus: 7Rescue: Wireless Power-Enabled Communication Architecture for Earthquake Rescue Operations(Elsevier, 2020) Badirkhanli, Orkhan; Akan, Ozgur B.; Ergul, OzgurIn a natural disaster such as an earthquake, it is vital to know the number of people trapped under the ruins. To address this problem, we propose RESCUE - wiREless backScattering CommUnication based disastEr recovery system. RESCUE is composed of special Radio-frequency identification (RFID) readers and sensors that are used to determine the total number of people under the ruins. Passive wireless sensor nodes are placed inside the building during construction and are equipped with a camera that is activated during an earthquake. After the earthquake, communication to the passive tags of sensors is achieved by wireless power transfer from a reader located outside the ruins. Tags harvest this energy and send the image data stored by the camera. We also design an antenna structure to maximize simultaneous wireless information and power transfer (SWIPT) for devices under ruins. We analyze the communication channel between reader and sensors and derive a channel model over ruins. Furthermore, we obtain the results of experimental study where we validate the derived channel model. Results show that RESCUE can collect the desired data in a relatively short time, and hence, is a promising disaster recovery system architecture. (C) 2019 Elsevier B.V. All rights reserved.Article Citation - WoS: 17Citation - Scopus: 19Bacterial Surface, Biofilm and Virulence Properties of listeriamonocytogenes Strains Isolated From Smoked Salmon and Fish Food Contact Surfaces(Elsevier, 2021) Sudagidan, Mert; Ozalp, Veli Cengiz; Ozturk, Orhan; Yurt, Mediha Nur Zafer; Yavuz, Orhan; Tasbasi, Behiye Busra; Aydin, AliBiofilm formation is one of the defense mechanisms of bacteria against disinfectants and antimicrobials. The aim of this study was to determine biofilm-forming L.monocytogenes from fish processing and salmon surfaces. Biofilm formation at 15, 25, 37, and 40 degrees C from 1 to 6-days period, adhesion to glass, polypropylene and stainless-steel surfaces, bacterial surface charge and hydrophobicity was determined. Adhesion behavior of the strains was evaluated using Surface Plasmon Resonance (SPR) technique. Totally 32 L.monocytogenes strains belonging to serogroups IIa (n:17), IIc(n:14) and IVb(n:1) were detected from 1320 swabs and 16 smoked salmons. Biofilm formation tests revealed that 21 strains form biofilm on microplate by increasing time and temperature. Although all strains strongly formed biofilm on glass surfaces, two strains slightly adhered polypropylene surfaces. High surface roughness of stainless-steel FeCrNi alloy (Ra = 4.15 nm) and CoCrMo alloy (Ra = 10.75 nm) increased biofilm formation of L.monocytogenes on stainless-steel surfaces. Zeta potential results showed that non-biofilm formers were more negatively charged after 6-days and hydrophobicity couldn't give a distinct distribution among biofilm formers and non-formers. SPR analysis method was evaluated to distinguish biofilm formers to adhere SPR gold chip surfaces. PCR results revealed that all strains were positive for hylA, iap, actA, plcA, plcB, fri, flaA, inlA, inlB, inlC, inlJ, and lmo1386 genes. Additionally, all strains were susceptible to penicillin, ampicillin, meropenem, erythromycin and trimethoprim-sulfamethoxazole. Biofilm-forming, virulence properties of L. monocytogenes strains isolated from fish processing surfaces and smoked salmons were evaluated and SPR was used to differentiate biofilm formers as a sensitive technique for biofilm studies.Article Citation - WoS: 22Citation - Scopus: 22Exploring Temperature-Dependent Bandgap and Urbach Energies in Cdte Thin Films for Optoelectronic Applications(Elsevier, 2024) Surucu, O.; Surucu, G.; Gasanly, N. M.; Parlak, M.; Isik, M.This study examines CdTe thin films deposited via RF magnetron sputtering, focusing on structural and optical properties. X-ray diffraction, Raman spectroscopy, and SEM assessed structural characteristics. Optical properties were analyzed through transmittance measurements from 10 to 300 K. Tauc plots and Varshni modeling revealed a temperature-dependent bandgap, increasing from 1.49 eV at room temperature to 1.57 eV at 10 K. Urbach energy rose from 82.7 to 93.7 meV with temperature. These results are essential for applications where temperature affects CdTe-based device performance.Article Citation - WoS: 35Citation - Scopus: 45Study on the Cytocompatibility, Mechanical and Antimicrobial Properties of 3d Printed Composite Scaffolds Based on Pva/ Gold Nanoparticles (aunp)/ Ampicillin (amp) for Bone Tissue Engineering(Elsevier, 2021) Topsakal, Aysenur; Midha, Swati; Yuca, Esra; Tukay, Ari; Sasmazel, Hilal Turkoglu; Kalaskar, Deepak M.; Gunduz, OguzhanOver the years, gold nanoparticles (AuNP) have been widely used in several biomedical applications related to the diagnosis, drug delivery, bio-imaging, photo-thermal therapy and regenerative medicine, owing to their unique features such as surface plasmon resonance, fluorescence and easy surface functionality. Recent studies showed that gold nanoparticles display positive effect on osteogenic differentiation. In line with this effect, 3-Dimesional (3D) scaffolds that can be used in bone tissue were produced by exploiting the properties of gold nanoparticles that increase biocompatibility and support bone tissue development. In addition, ampicillin was added to the scaffolds containing gold nanoparticles as a model drug to improve its antimicrobial properties. The scaffolds were produced as composites of polyvinyl alcohol (PVA) main matrix as PVA, PVA/AuNP, PVA/Ampicillin (AMP) and PVA/AuNP/AMP. Scanning Electron Microscopy (SEM) Fourier Transform Infrared Spectroscopy (FTIR), tensile measurement tests, and in vitro applications of 3D scaffolds were performed. As depicted by SEM, scaffolds were produced at pore sizes appropriate for bone tissue regeneration. According to FTIR results, there was no modification observed in the AMP, PVA and gold nanoparticles due to mixing in the resultant scaffolds. In vitro results show that 3D printed composite scaffold based on PVA/AuNP/AMP are biocompatible, osteo-inductive and exhibit antimicrobial properties, compared to PVA scaffolds. This study has implications for addressing infections during orthopedic surgeries. The PVA-based gold nanoparticle 3D tissue scaffold study containing ampicillin covers a new study compared to other articles based on gold nanoparticles.Article Citation - WoS: 40Citation - Scopus: 51Towards a Circular Economy: Investigating the Critical Success Factors for a Blockchain-Based Solar Photovoltaic Energy Ecosystem in Turkey(Elsevier, 2021) Erol, Ismail; Peker, Iskender; Ar, Ilker Murat; Turan, Ismet; Searcy, CoryNovel business models can be implemented through digital platforms to enable better circular economy (CE) performance in the renewable energy industry. For example, blockchain can assist in developing innovative business models throughout the solar photovoltaic energy ecosystem (SPVEE) to improve CE. Ranked fifth in total installed photovoltaic (PV) capacity, Turkey, as a developing country, should take the necessary steps and make progress towards achieving CE in the SPVEE. The solar PV industry requires further innovation to address the negative environmental impact of existing linear business models. To ensure favorable results, identifying and evaluating critical success factors (CSFs) are necessary. However, no study has investigated CSFs for SPVEE or any other renewable energy source to achieve a blockchain-based infrastructure towards increased CE performance. Therefore, the goal of this study is to identify and examine the CSFs to improve the performance of a blockchain-based SPVEE towards CE in Turkey. To this end, first, the CSFs for blockchain-based SPVEE were identified through both a literature review and the Nominal Group Technique (NGT). Then, Intuitionistic Fuzzy (IF)DEMATEL was used to explore their interrelationships based on the expert data. Finally, IF-DELPHI was employed to validate the results. Our findings suggested that effective government incentive programs and regulations are significant for blockchain-based SPVEE towards CE in Turkey. The findings of this study assist macro and micro decision-making in the potential implementation of blockchain in Turkish SPVEE to improve CE. They are also invaluable for other countries and can be used as a reference point. (c) 2021 International Energy Initiative. Published by Elsevier Inc. All rights reserved.Article Citation - WoS: 26Citation - Scopus: 29Assessing Dependency of Part Properties on the Printing Location in Laser-Powder Bed Fusion Metal Additive Manufacturing(Elsevier, 2022) Mussatto, Andre; Groarke, Robert; Vijayaraghavan, Rajani K.; Hughes, Cian; Obeidi, Muhannad Ahmed; Dogu, Merve Nur; Brabazon, DermotDespite the accelerated growth of laser-powder bed fusion in recent years, there are still major obstacles to be overcome before the technology enjoys truly widespread adoption. These include inconsistent part quality and repeatability issues linked to variability in the properties of printed parts. Commonly, the print location across the build platform is overlooked and assumed to have little or no effect on the overall part properties. There is a lack of previous systematic studies and a lack of knowledge of the influences of the location parameter on the final part properties. Therefore, to address the existing problem, the current study completely isolated the location parameter to accurately assess any effect of this variable on the microstructure and mechanical properties of laser-powder bed fusion manufactured parts. The results revealed the importance of the build location and showed that there is correlation between the location parameter and part properties as qualitative and quantitative properties of printed parts varied between the selected extremity locations. The findings highlight the importance of considering the location of the part being printed on the build platform and how the location may need to be fixed for multiple builds in order to achieve acceptable repeatability.Article Citation - WoS: 5Citation - Scopus: 5Identification of Shallow Trap Centers in Inse Single Crystals and Investigation of Their Distribution: a Thermally Stimulated Current Spectroscopy(Elsevier, 2024) Isik, M.; Gasanly, N. M.Identification of trap centers in semiconductors takes great importance for improving the performance of electronic and optoelectronic devices. In the present study, we employed the thermally stimulated current (TSC) method within a temperature range of 10-280 K to explore trap centers in InSe crystal-a material with promising applications in next-generation devices. Our findings revealed the existence of two distinct hole trap centers within the InSe crystal lattice located at 0.06 and 0.14 eV. Through the leveraging the T-stop method, we offered trap distribution parameters of revealed centers. The results obtained from the experimental methodology employed to investigate the distribution of trap centers indicated that one of the peaks extended between 0.06 and 0.13 eV, while the other spanned from 0.14 to 0.31 eV. Notably, our research uncovers a remarkable variation in trap density, spanning one order of magnitude, for every 10 and 88 meV of energy variation. The results of our research present the characteristics of shallow trap centers in InSe, providing important information for the design and optimization of InSe-based optoelectronic devices.Review Citation - WoS: 4Citation - Scopus: 4Smart Hydrogels in Lab-On (loc) Applications(Elsevier, 2024) Tevlek, Atakan; Cretin, Esin AkbayLaboratory on-chip (LOC) technology facilitates numerous developments across diverse disciplines, such as medicine, tissue engineering, materials science, biomedical engineering, and biotechnology. Moreover, the potential applications appear boundless when LOC is integrated with intelligent hydrogels. In the literature, however, there are few accounts of the vast array of developments and applications that this combination has spawned. These new systems, which integrate smart hydrogels and LOC and thus significantly advance cuttingedge technology, have been thoroughly examined in this review. The functions of smart hydrogels in LOC applications were described and subsequently the developed intelligent hydrogels were classified as multiresponsive, thermo-responsive, pH-responsive, and stimuli-responsive (light, magnetic, and electric). Following this, details regarding tunable properties for LOC functions were provided, followed by a discussion of the fabrication processes and integration of these intelligent hydrogels into LOC systems, including their benefits and drawbacks. Following that, current literature examples of LOC systems utilizing these intelligent hydrogels for biosensing, 3D culture, tissue engineering, controlled release, personalized medicine, drug delivery, analyte enrichment, and organ-on-a-chip applications were presented. Following the presentation of state-of-the-art information regarding smart hydrogel characterization techniques, present challenges and prospective prospects were discussed.Editorial Citation - WoS: 47Citation - Scopus: 47Emergency Changes in International Guidelines on Treatment for Head and Neck Cancer Patients During the Covid-19 Pandemic(Elsevier, 2020) Chaves, Aline Lauda Freitas; Castro, Ana Ferreira; Marta, Gustavo Nader; Junior, Gilberto Castro; Ferris, Robert L.; Giglio, Raul Eduardo; Kowalski, Luiz Paulo[No Abstract Available]
