PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
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Data Paper Citation - WoS: 2Citation - Scopus: 3Assessing Museums' Daylighting Adequacy Without Annual Measurement Campaign: Dataset of a Confrontation Between Measured and Simulated Illuminance Values Inside the Cetacean Gallery of the Charterhouse of Calci(Elsevier Ltd., 2020) Leccese, Francesco; Salvadori, Giacomo; Tambellini, Giuseppe; Kazanasmaz, Zehra TuğçeLighting Cultural Heritage is a complex task: light is necessary for the act of seeing, it can even enhance the visual experience [1,2], in addition proper lighting can significantly cut down energy consumptions [3], but on the same time it has detrimental effects on exhibits, especially daylight. In order to safeguard the exhibits from damages, national and international standards provide specific recommendations for exhibits' exposure, based on their photosensitivity category. These recommendations are the annual luminous exposure(LO) and the Maximum Illuminance Level (E-max), museums' curators have to verify that the display lighting conditions comply with the standards. Historical buildings are often converted into museums but, as their original purpose was different, the lighting conditions are often inadequate (e.g. too much uncontrolled daylight), therefore the lighting conditions' adequacy of the space should be assessed [4]. As the name suggest the annual luminous exposure requires an annual monitoring campaign, unfortunately it often happens that exhibits have been exposed incorrectly for prolonged periods, and therefore it is very important to evaluate the need of a fast intervention. In this casuistry a prolonged measurement campaign is not acceptable. Simulations can help running a great number of analysis while reducing the length and expenses of a measurements campaign, however their previsions must be validated. This paper provides the data acquired through measurements and simulations inside the Cetacean Gallery of the Monumental Charterhouse of Calci, near Pisa (Tuscany Region, Italy). The data comprehends horizontal and vertical illuminance measurements, recorded on December the 6th, and simulations run in Grasshopper with the plugins Honeybee+ and Ladybug. The data are related to the research article entitled "Application of climate-based daylight simulation to assess lighting conditions of space and artworks in historical buildings: the case study of Cetacean Gallery of the Monumental Charterhouse of Calci", published on the Journal of Cultural Heritage [5]. (C) 2020 The Author(s). Published by Elsevier Inc.Article Citation - WoS: 19Genotypic Identification of Some Lactic Acid Bacteria by Amplified Fragment Length Polymorphism Analysis and Investigation of Their Potential Usage as Starter Culture Combinations in Beyaz Cheese Manufacture(Elsevier Ltd., 2010) Karahan, A. G.; Kilic, G. Basyigit; Kart, A.; Aloglu, H. Sanlidere; Oner, Z.; Aydemir, S.; Harsa, Hayriye Şebnem; Erkuş, OylumIn this study, 2 different starter culture combinations were prepared for cheesemaking. Starter culture combinations were formed from 8 strains of lactic acid bacteria. They were identified as Lactococcus lactis ssp. lactis (2 strains), Lactobacillus plantarum (5 strains), and Lactobacillus paraplantarum (1 strain) by amplified fragment length polymorphism analysis. The effects of these combinations on the physicochemical and microbiological properties of Beyaz cheeses were investigated. These cheeses were compared with Beyaz cheeses that were produced with a commercial starter culture containing Lc. lactis ssp. lactis and Lc. lactis ssp. cremoris as control. All cheeses were ripened in brine at 4 degrees C for 90 d. Dry matter, fat in dry matter, titratable acidity, pH, salt in dry matter, total N, water-soluble N, and ripening index were determined. Sodium dodecyl sulfate-PAGE patterns of cheeses showed that alpha(S)-casein and beta-casein degraded slightly during the ripening period. Lactic acid bacteria, total mesophilic aerobic bacteria, yeast, molds, and coliforms were also counted. All analyses were repeated twice during d 7, 30, 60, and 90. The starter culture combinations were found to be significantly different from the control group in pH, salt content, and lactobacilli, lactococci, and total mesophilic aerobic bacteria counts, whereas the cheeses were similar in fat, dry matter content, and coliform, yeast, and mold counts. The sensory analysis of cheeses indicated that textural properties of control cheeses presented somewhat lower scores than those of the test groups. The panelists preferred the tastes of treatment cheeses, whereas cheeses with starter culture combinations and control cheeses had similar scores for appearance and flavor. These results indicated that both starter culture combinations are suitable for Beyaz cheese production.Article Citation - WoS: 71Citation - Scopus: 76Characterization of Bacterial Cellulose Nanocrystals: Effect of Acid Treatments and Neutralization(Elsevier Ltd., 2021) Arserim-Uçar, Dilhun Keriman; Korel, Figen; Liu, LinShu; Yam, Kit LIn this study, bacterial cellulose nanocrystals (BCNCs) were obtained from bacterial cellulose nanofibers (BCNFs) by controlled hydrolysis of sulfuric and hydrochloric acids. The influence of hydrolysis temperature and acid type with the addition of the post-treatment step was studied. The obtained BCNCs were analyzed based on the structural characterization and the properties of the nanocrystals. The BCNCs crystallinity increased, and the size of nanocrystals decreased with increasing 10 °C hydrolysis temperature for both acid hydrolysis conditions. Hydrolysis conditions with neutralization post-treatment did not alter the thermal stability of nanocrystals, and BCNCs had high thermal stability like raw BCNFs. Elemental analysis results indicated that sulfur content (S %) was very low for sulfuric acid hydrolyzed samples, and X-ray results did not show any sulfate salt peaks. Thermal stable BCNCs with high crystallinity were successfully produced to meet the process requirements in various applications, especially in the food industry.Article Citation - WoS: 24Citation - Scopus: 26Self-Assembly Behavior of the Keratose Proteins Extracted From Oxidized Ovis Aries Wool Fibers(Elsevier Ltd., 2019) Pakkaner, Efecan; Yalçın, Damla; Uysal, Berk; Top, AybenWater soluble keratose proteins were obtained from an Ovis Aries wool using peracetic acid oxidation. The wool samples and the extracted keratose proteins were characterized by using FTIR, XRD, SEM and TGA techniques. Fractions of alpha-keratose (MW = 43-53 kDa) along with protein species with molecular weights between 23 kDa and 33 kDa were identified in the SDS-PAGE analysis result of the extracted protein mixture. DLS and AFM experiments indicated that self-assembled globular nanoparticles with diameters between 15 nm and 100 nm formed at 5 mg/ml keratose concentration. On the other hand, upon incubation of 10 w % keratose solutions at 37 degrees C and 50 degrees C, interconnected keratose hydrogels with respective storage modulus (G') values of 0.17 +/- 0.03 kPa and 3.7 +/- 0.5 kPa were obtained. It was shown that the keratose hydrogel prepared at 37 degrees C supported L929 mouse fibroblast cell proliferation which suggested that these keratose hydrogels could be promising candidates in soft tissue engineering applications. (C) 2018 Elsevier B.V. All rights reserved.Article Citation - WoS: 15Citation - Scopus: 19Brominated Flame Retardants in a Computer Technical Service: Indoor Air Gas Phase, Submicron (pm1) and Coarse (pm10) Particles, Associated Inhalation Exposure, and Settled Dust(Elsevier Ltd., 2019) Genişoğlu, Mesut; Sofuoğlu, Aysun; Kurt Karakuş, Perihan Binnur; Birgül, Aşkın; Sofuoğlu, Sait CemilBrominated flame retardants (BFRs) are found in multi-media indoors, therefore, may pose serious risks to human health. This study investigated the occurrence of BFRs in particulate matter (PM1 and PM10) and gas phase by active and passive sampling, and settled dust to estimate potential exposure in a computer technical service. Polybrominated diphenyl ethers (PBDEs) and their alternatives (novel BFRs, NBFRs) were studied. PM and gas phase were collected on glass fiber filters and polyurethane foam plugs, respectively, and analyzed with a GC/MS after extraction, clean-up, and concentration. Inhalation exposure of the staff was estimated based on the measured concentrations using Monte Carlo simulation. BDE-209 was the dominating PBDE congener in all media while bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate and 1,2-bis(2,4,6-tribromophenoxy)ethane were those of NBFRs. Submicron particulate matter (PM1) BFR levels constituted about one half of the PM10-associated concentrations, while average PM10 mass concentration (69.9 μg m−3) was nine times that of PM1 (7.73 μg m−3). Calculated log10 dust-gas and PM-gas partitioning coefficients ranged from −5.03 to −2.10, −2.21 to −0.55, and −2.26 to −1.04 for settled dust, PM10, and PM1, respectively. The indoor/outdoor concentration ratios were >1 for all compounds indicating the strength of indoor sources in the service. The estimated potential inhalation exposures, for future chronic-toxic and carcinogenic risk assessments, indicated that the levels of gas-phase and PM1-associated exposures were similar at approximately one half of PM10-associated levels. Results of this study indicate that the occurrence of BFRs in all studied media should be taken into consideration for occupational health mitigation efforts.Article Citation - WoS: 12Citation - Scopus: 14Thermodynamically Designed Target-Specific Dna Probe as an Electrochemical Hybridization Biosensor(Elsevier Ltd., 2020) Can, Faruk; Ökten, Hatice Eser; Ergön Can, Tülay; Ergenekon, Pınar; Özkan, Melek; Erhan, ElifApplications of molecular techniques to elucidate identity or function using biomarkers still remain highly empirical and biosensors are no exception. In the present study, target-specific oligonucleotide probes for E. coli K12 were designed thermodynamically and applied in an electrochemical DNA biosensor setup. Biosensor was prepared by immobilization of a stem–loop structured probe, modified with a thiol functional group at its 5′ end and a biotin molecule at its 3′ end, on a gold electrode through self-assembly. Mercaptopropionic acid (MPA) was used to optimize the surface probe density of the electrode. Hybridization between the immobilized probe and the target DNA was detected via the electrochemical response of streptavidin-horseradish peroxidase in the presence of the substrate. The amperometric response showed a linear relationship with the target DNA concentration, ranging from 10 and 400 nM, with a correlation coefficient of 0.989. High selectivity and good repeatability of the biosensor showed that the thermodynamic approach to oligonucleotide probe design can be used in development of electrochemical DNA biosensors.Article Citation - WoS: 34Citation - Scopus: 35Development of High Flux Nanofiltration Membranes Through Single Bilayer Polyethyleneimine/Alginate Deposition(Elsevier Ltd., 2019) Tekinalp, Önder; Alsoy Altınkaya, SacideThe aim of this study is to prepare high flux, stable, antifouling nanofiltration membranes through single bilayer polyelectrolyte deposition. To this end, a tight ultrafiltration support membrane was prepared from a polysulfone/sulfonated polyethersulfone blend. Deposition of a polyethyleneimine and alginate pair on this support has reduced the molecular weight cut off from 6 kDa to below 1 kDa. The pure water permeability and polyethylene glycol 1000 rejection of the coated membrane were found to be 15.5 ± 0.3 L/m2·h·bar and 90 ± 0.6%, respectively, by setting the deposition pH for each layer to 8 and the ionic strengths to 0.5 M and 0 M. This membrane has exhibited significantly higher permeability than commercial membranes with the same molecular weight cut off, retaining 98% of the initial flux during 15 h filtration of bovine serum albumine. In addition, the membrane has been able to completely remove anionic dyes from aqueous solution by showing 99.9% retentions to Reactive red 141, Brilliant blue G and Congo red with a 2 bar transmembrane pressure. High flux and membrane stability in acidic and salty environments have been achieved when deposition conditions favor high adsorption levels for the first layer and strong ionic cross-linking between the carboxyl group on the alginate and the amine groups on the polyethyleneimineArticle Citation - WoS: 15Citation - Scopus: 13Phase Behavior of Dspc/Peg40st Mixtures at Higher Emulsifier Contents(Elsevier Ltd., 2018) Kılıç, Sevgi; Bölükçü, Elif ŞenizPhase behaviors of 1,2-Distearoyl-sn-glycero-3-phosphocholine (DSPC) and polyoxyethylene(40)stearate (PEG40St) were investigated with Langmuir monolayer isotherms and Brewster angle microscopy (BAM) imaging at DSPC/PEG40St molar ratios ranging from 9:1 to 5:5. Two plateaus were found in the Langmuir isotherms which were relatively shorter for the 9:1 mixture and extended significantly by increasing the PEG40St content, indicating that the PEG40St squeezed out whereas more emulsifier retained in the monolayer at higher PEG40St contents. A strong hysteresis was observed when the mixed monolayers were subjected to compression-expansion cycles. The degree of hysteresis for the first cycles also increased with increasing PEG40St content in the monolayer. Gray scale intensities in the Brewster angle microscopy images were determined for pure DSPC and pure PEG40St and a scale was established to better interpret the morphologies for the mixtures. Bud and vessels formed during the PEG40St squeezed out upon compression. Upon expansion, PEG40St and DSPC is reappeared on the monolayer. When considered BAM images together with the Langmuir isotherm, PEG40St molecules were found to be well distributed within the DSPC molecules at lower DSPC/PEG40St mole ratios and mostly phase separated at higher mole ratios. It was concluded that higher PEG40St content would be advantageous for the design of an efficient and cheaper ultrasound contrast agents.Article Citation - WoS: 51Citation - Scopus: 60Biosilica Incorporated 3d Porous Scaffolds for Bone Tissue Engineering Applications(Elsevier Ltd., 2018) Tamburacı, Sedef; Tıhmınlıoğlu, FundaAs a natural and abundant silica mineral, diatomite particles (SiO2-nH2O) have been used in several areas such as filtration, photonics, sound and heat insulation, filler material and drug delivery due to its abundance, inexpensive cost, unique morphology and porous structure. But up to date, diatomite incorporated silica based scaffolds have not been used for bone tissue engineering applications. In the present study, the goal was to combine the useful biomaterial properties of both chitosan and diatomite as biocomposite organic/inorganic biomaterial for bone tissue engineering applications and optimize the silica content of the composites in order to obtain optimum morphological structure, high mechanical properties, enlarged surface area and enhanced cell proliferation. The effect of silica loading on the mechanical, morphological, chemical, and surface properties, wettability and biocompatibility of composite scaffolds were investigated. In addition, in vitro cytotoxicity and cellular activities including cell proliferation, ALP activity and biomineralization were investigated in order to determine biological activity of the composite scaffolds. Diatomite particles lead to enhancement in the water uptake capacity of scaffolds. Chitosan-silica composites exhibited 82–90% porosity. Wet chitosan-silica composite scaffolds exhibited higher compression moduli when compared to pure chitosan scaffold in the range of 67.3–90.1 kPa. Average pore size range of chitosan-diatomite composite scaffolds was obtained as 218-319 μm. In vitro results indicated that chitosan-diatomite composites did not show any cytotoxic effect on 3T3, MG-63 and Saos-2 cell lines. Scaffolds were found to be favorable for osteoblast proliferation. Diatomite incorporation showed promising effects on enhancing ALP activity as well as mineral formation on scaffold surface. Thus, the prepared scaffolds in this study can be considered prospective material for bone tissue engineering applications.Article Citation - WoS: 91Citation - Scopus: 95Source Apportionment and Carcinogenic Risk Assessment of Passive Air Sampler-Derived Pahs and Pcbs in a Heavily Industrialized Region(Elsevier Ltd., 2018) Çetin, Banu; Yurdakul, Sema; Güngörmüş, Elif; Öztürk, Fatma; Sofuoğlu, Sait CemilCancer has become the primary reason of deaths in Dilovasi probably due to its location with unique topography under the influence of heavy industrialization and traffic. In this study, possible sources and carcinogenic health risks of PAHs and PCBs were investigated in Dilovasi region by Positive Matrix Factorization (PMF) and the USEPA approach, respectively. PAHs and PCBs were measured monthly for a whole year at 23 sampling sites using PUF disk passive samplers. Average ambient air concentrations were found as 285 ± 431 ng/m 3 and 4152 ± 6072 pg/m 3 , for Σ 15 PAH and Σ 41 PCB, respectively. PAH concentrations increased with decreasing temperature especially at urban sites, indicating the impact of residential heating in addition to industrial activities and traffic. On the other hand, PCB concentrations mostly increased with temperature probably due to enhanced volatilization from their sources. Possible sources of PAHs were found as emissions of diesel and gasoline vehicles, biomass and coal combustion, iron and steel industry, and unburned petroleum/petroleum products, whereas iron-steel production, coal and biomass burning, technical PCB mixtures, and industrial emissions were identified for PCBs. The mean carcinogenic risk associated with inhalation exposure to PAHs and PCBs were estimated to be >10 −6 and >10 −5 , respectively, at all sampling points, while the 95th percentile was >10 −5 at 15 of 23 and >10 −4 at 8 of 23 sampling locations, respectively. Probabilistic assessment showed, especially for PCBs, that a majority of Dilovasi population face significant health risks. The higher risks due to PCBs further indicated that PCBs and possibly other pollutants originating from the same sources such as PBDEs and PCNs may be an important issue for the region.