IYTE GCRIS Database (Izmir Institute of Technology)
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Fabrication of Electrospun Polycaprolactone Nanofibrous Mats Loaded With Purple Basil Extract (Ocimum Basilicum L.) as Colorimetric Ph Indicator Films
No full textIntelligent packaging with colorimetric pH indicators revolutionizes traditional food packaging by enabling real-time food quality monitoring. This study used electrospinning to develop pH indicator films from polycaprolactone (PCL) incorporating purple basil extract (PBE). Nanofibrous films containing 0.2% PBE (PCLN_0.2PBE), 0.4% PBE (PCLN_0.4PBE), and 0.6% PBE (PCLN_0.6PBE) were fabricated using different electrospinning conditions. The PCLNs fabricated with a voltage of 20 kV and a flow rate of 1.6 mL/h exhibited the most uniform and bead-free morphology according to scanning electron microscopy. The chemical, thermal, mechanical, and wetting characterization of the films was performed by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermal gravimetric analysis, texture analysis, and contact angle analysis, respectively. Both PCLN_0.4PBE and PCLN_0.6PBE films displayed fast (4-5 s) and clear color transitions (Delta E > 3.5) to successive pH buffers within the range critical for food deterioration, while they exhibited excellent color changes (Delta E > 5) for pH variations of at least two units. The PCLN_0.6 PBE film displayed a Delta E of similar to 5 in only 5 min of exposure to ammonia vapor, whereas PCLN_0.4PBE showed a similar color change for over 15 min. The interaction between the films and acidic and alkaline semi-solid foods was simulated using gelatin gels at pH 2.5 and 11, respectively. Both films displayed significant color transitions (Delta E > similar to 9) within 15 min of contact with the gels, with the response from PCLN_0.6 PBE being more pronounced. The color stability in both films was maintained for up to 14 days at 4 degrees C, offering potential early warnings against food spoilage. PBE release was evaluated against different food simulants. The highest release occurred in 50% ethanol; the films demonstrated resistance to 3% acetic acid. The findings indicate that electrospun PCL films integrated with PBE have a promising potential to serve as colorimetric pH indicators for monitoring the freshness of food products
Mimari Tasarım Bürolarının Kurumsal Çevrenin Zorlayıcı Baskısına Karşı Stratejik Tepkileri
No full textBu çalışmada mimari tasarım bürolarının faaliyet gösterdiği kurumsal çevrelerinde karşılaştıkları baskılara karşılık verdikleri stratejik tepkiler incelenmiştir. Çalışmada tasarım odaklı pratik alanları olan mimari tasarım bürolarının öncelikli kurumsal çevre unsuru yapı ve imar yönetmeliklerine karşı izledikleri stratejiler araştırılmıştır. Anket yöntemiyle araştırma verileri toplanmıştır. Elde edilen veriler istatistiksel yöntemlerle analiz edilmiştir. Araştırma bulgularına göre mimari tasarım büroları kurumsal çevrelerinde pasif bir yaklaşım göstermektedir
Magnetic Levitational Assembly of Differentiated Sh-Sy5y Cells for Aβ-Induced 3d Alzheimer's Disease Modeling and Curcumin Screening
No full textAlzheimer's disease is one of the prevalent neurodegenerative diseases and is characterized by amyloid beta aggregate (A beta) accumulation. This study reports an A beta 1-42 induced 3D Alzheimer's disease modeling utilizing differentiated SH-SY5Y spheroids, which is carried out by Magnetic levitation approach, and the neuroprotective effect of Curcumin is further investigated on this model. For this purpose, SH-SY5Y spheroids are differentiated using Retinoic acid-Brain-derived neurotrophic factor sequentially during 3D cell culture. Differentiated spheroids maintained high viability and exhibited significant neuronal characteristics, as evidenced by increasing beta-III tubulin and NeuN expressions. 3D Alzheimer's disease model formation and neurotoxicity of A beta 1-42 aggregates are investigated on un-/differentiated spheroids, resulting in 65% and 51% cell viability, respectively. Characterization of the 3D Alzheimer's disease model is done by immunostaining of Choline acetyltransferase to investigate cholinergic neuron activity loss, showing a 2.2 decrease in fluorescence intensity. Further, Curcumin treatment on the 3D Alzheimer's disease model resulted in augmenting cell viability, confirming neuroprotective effect of Curcumin on A beta 1-42 induced Alzheimer's disease model. This study highlighted the magnetic levitation-based fabrication of A beta 1-42-induced 3D Alzheimer's disease model successfully, offering a promising experimental platform for other neurodegenerative disease research and potential clinical applications
Integration of Leu-Asp Cell Attachment Motif Into Self-Assembling Peptide Sequences for Nanofibrillar Hydrogel Formation in Wound Healing
No full textFunctionalizing peptide sequences with cell adhesion motifs enhances their cellular bioactivity. Numerous studies have focused on incorporating the Arg-Gly-Asp (RGD) motif into peptide hydrogels; however, the integration of other bioactive domains has yet to be comprehensively investigated. In this study, one of the essential fibronectin-derived cell-binding domains, Leu-Asp-Val (LDV), was integrated into the self-assembling peptide to obtain extracellular matrix (ECM)-mimetic nanofibrillar hydrogelators. IBP1A (NH2-KLDVKLDVKLKV-CONH2) and IBP1B (NH2-KLDVKLDVKLDV-CONH2) peptides were designed accordingly. These peptides self-assemble into hydrogels in phosphate-buffered saline (PBS) at pH 7.4 and deionized water at neutral pH with storage modulus values between similar to 200 and similar to 2000 Pa. Flow curves and the cyclic strain sweep data confirmed that the hydrogels have shear thinning, injectability, and self-healing properties. Flexible nanofibrillar morphology was observed in the TEM images. Nanofibril widths of IBP1A and IBP1B networks were measured as 8.2 +/- 1.1 and 4.5 +/- 0.8 nm, respectively. In vitro tests were also conducted to evaluate these peptides in wound healing applications. The IBP1A peptide with a +3 charge at neutral pH exhibited modest antibacterial activity against Gram (+) and Gram (-) bacteria. In vitro cell culture experiments show that the IBP1A and IBP1B hydrogels promoted the growth of fibroblast cells and glycosaminoglycan secretion compared with the KLDL12 control peptide, which does not contain the LDV motif. The designed hydrogels induced cell attachment within 72 h by altering the cell morphology similar to their natural 3D microenvironment, whereas cells exhibited spindle-like morphology on the KLDL12 hydrogel and tissue culture polystyrene (TCP). Moreover, IBP1B accelerated in vitro wound healing by facilitating fibroblast migration. These results suggest that these bioactive injectable peptide hydrogels have potential in wound healing and skin tissue regeneration
Assessment of Seismic Liquefaction and Structural Instability in Adiyaman-Golbasi After the February 6, 2023, Earthquakes in Türkiye
No full textTwo earthquakes, Mw = 7.8 Kahramanmaras,-Pazarcik, and Mw = 7.6 Elbistan, occurred on February 6, 2023, approximately 9 h apart. These earthquakes caused devastating effects in a total of 11 nearby cities on the east side of T ; uuml;rkiye (Adana, Adiyaman, Diyarbakir, Elazig, Gaziantep, Hatay, Kahramanmaras,, Kilis, Malatya, Osmaniye, and S,anliurfa) and the north side of Syria. These earthquakes provided an outstanding prospect to observe the effects of liquefaction in silty sand and liquefaction-like behavior in clays (cyclic softening) on the stability of structures. This paper specifically presents the post-earthquake reconnaissance at three sites and evaluations of four buildings within these sites in Adiyaman Province, Golbas, i District. First, important role of post-earthquake piezocone penetration test (CPTu) in characterizing the subsurface conditions was presented. Then, the effect of soil liquefaction and cyclic softening on the performance of four buildings during the earthquakes was evaluated. These structures represent the typical new reinforced concrete buildings in T ; uuml;rkiye with 3 to 6-story, situated on shallow (raft) foundations, and demonstrated diverse structural performances from full resilience to moderate and extensive damage during the aforementioned earthquakes. Based on the interim findings from these sites, the potential factors that caused moderate to severe damage to buildings were inspected, and preliminary-immediate insights were presented on the relationship between structural design, soil properties, and the performance of buildings with shallow foundations
Her yönüyle yapay zeka
No full textUluslararası Kıbrıs Üniversitesi ev sahipliğinde KKTC'de 13-14 Nisan 2025 tarihinde gerçekleştirilen Yapay Zeka ve Üniversite Kütüphaneler Çalıştayında yapılan sunumdur
Retrospective Bim Performance Analysis Based on Construction Big Data
No full textPurposeThe literature suggests employing big data and Building Information Modeling (BIM) to examine building projects from several perspectives. Nevertheless, the literature is deficient in thorough BIM performance evaluation methods grounded in big construction project data. This paper presents an evaluation framework outlining the data input requirements and necessary data to conduct research leveraging big data for the analysis of BIM performance.Design/methodology/approachData parameters and performance metrics included in the evaluation framework are derived from a synthesis of literature review, data overview and interviews. The construction data was analyzed using PowerBI after undergoing a quality control process. Analysis results were verified through interviews with the main contractor. The project data served to assess the evaluation framework.FindingsThe evaluation framework has ten data parameters, and six performance metrics categorized into three main categories. The findings indicate that the evaluation framework can be utilized to comment on BIM performance in a project, with a level of accuracy. Results indicated that ensuring the quality of tracked project data is crucial for obtaining reliable analysis results. Determining performance metrics and data parameters prior to data recording processes can help simplify the analysis process and ensure accurate analysis results.Originality/valueThe proposed framework offers a comprehensive performance evaluation methodology that leverages the innovative application of unique and challenging to acquire big data, allowing practitioners to assess BIM performance in relation to project time, cost and scope. Identified data parameters and novel performance metrics may provide the foundation of a guideline for construction project data logging to facilitate accurate BIM performance monitoring
Production and Applications of Si-Based Aerogels
No full textThis dissertation explores the production and applications of Si-based preceramic and ceramic aerogels and their composites through the polymer-derived ceramic (PDC) approach. Neat aerogels and their composites in polymeric, hybrid, and ceramic states were analyzed deeply for processing-structure-property relationships. The first section provides an overview of aerogels, PDCs, motivation, and goals. Chapter 2 presents research on the design and performance of SiOC ambi/aerogels produced via using a readily available polysiloxane by ambient pressure drying (ambigels) and CO2 supercritical drying. Such materials exhibited promising oil sorption (up to 3.1 g·g–1). and water cleaning performance, coupled with low thermal conductivity (0.046 W·m–1·K–1) at RT and (0.073 W·m–1·K–1) 500 °C. Chapter 3 covers the manufacturing of novel SiOC foam-aerogel composites to demonstrate the manufacturing feasibility of highly porous aerogel monoliths, machinable into various forms while preserving their superior insulating abilities up to 1200 °C under a butane torch hit compared to commercial insulation panels. Chapter 4 investigates the developments of monolithic hybrid preceramic ambi/aerogels, highlighting their potential for oil/organic solvent cleanup. These aerogels demonstrate high sorption capacities, reaching up to 13 g·g–1 for oil, and 11 g·g-1 for solvents, maintaining stable sorption over multiple regeneration cycles with organic solvents. Chapter 5 examines the design of inorganic composites, combining SiOC foam and silica aerogel, to achieve outstanding thermal management at high and low temperatures. Overall, Si-based preceramic and ceramic aerogels exhibited promising multifunctional properties, including low thermal conductivity, efficient thermal insulation, high-temperature stability, and wastewater treatment.Bu tez, Si-bazlı polimerik ve seramik aerojellerin ve kompozit yapılarının polimer türevli seramik (polymer derived ceramic, PDC) yaklaşımıyla üretimini ve uygulamalarını araştırmaktadır. Polimerik, hibrit ve seramik yapıdaki saf aerojeller ve köpük-aerojel kompozitleri, işleme-yapı-özellik ilişkileri açısından derinlemesine analiz edilmiştir. İlk bölüm aerojeller, PDC'ler, motivasyon ve hedeflere genel bir bakış sunmaktadır. 2. Bölüm, ortam basıncında kurutma (ambijeller) ve CO2 süperkritik kurutma yoluyla kolayca temin edilebilen bir polisiloksan polimeri kullanılarak üretilen SiOC ambi/aerojellerinin tasarımı ve performansına ilişkin araştırmayı sunmaktadır. Bu malzemeler, oda sıcaklığında (0,046 W·m–1·K–1) ve 500 °C'de (0,073 W·m–1·K–1) düşük ısıl iletkenlikle birlikte umut verici yağ emilimi (3,1 g·g–1'e kadar) ve su temizleme performansı sergilemiştir. Bölüm 3, ticari yalıtım panellerine kıyasla 1200 °C'ye kadar bütan meşalesi altında üstün yalıtım ve mekanik özelliklerini koruyabilen, çeşitli formlara işlenebilir, yüksek gözenekli aerojel monolitlerinin üretim fizibilitesini gösteren SiOC köpük-aerojel kompozit yaklaşımını ele almaktadır. Bölüm 4, monolitik hibrit ambi/aerojellerin geliştirilmesini inceleyerek, yağ/organik çözücü temizliği için potansiyellerini vurgulamaktadır. Bu aerojeller, yağ için 13 g·g–1'e ve çözücüler için 11 g·g–1'e kadar ulaşan yüksek sorpsiyon kapasiteleri göstermektedir ve organik çözücülerle birden fazla rejenerasyon döngüsü boyunca kararlı sorpsiyon sağlamaktadır. Bölüm 5, yüksek ve düşük sıcaklıklarda olağanüstü termal yönetim elde etmek için SiOC köpüğü ve silika aerojeli birleştiren inorganik kompozitlerin tasarımını incelemektedir. Genel olarak, Si bazlı polimerik ve seramik aerojeller, düşük termal iletkenlik, verimli termal yalıtım, yüksek sıcaklık stabilitesi ve atık su arıtımı dahil olmak üzere umut verici çok işlevli özellikler sergilemiştir
Type-Ii Topological Phase Transitions of Topological Skyrmion Phases
No full textWe present minimal toy models for topological skyrmion phases of matter, which generically realize type-II topological phase transitions in effectively noninteracting systems, those which occur without closing of the minimum direct bulk energy gap. We study the bulk-boundary correspondence in detail to show that a nontrivial skyrmion number yields a rich bulk-boundary correspondence. We observe gapless edge states, which are robust against disorder, due to nontrivial skyrmion number. Edge states corresponds to bands, which do not traverse the bulk gap, instead yielding gaplessness due to their overlap in energy and exponential localization on opposite edges of the system. These gapless boundary modes can occur for total Chern number zero, and furthermore correspond to rich real-space spin textures with strong polarization of spin along the real-space edge. By introducing toy models generically exhibiting type-II topological phase transitions and characterizing the bulk-boundary correspondence due to nontrivial skyrmion number in these models, we lay the groundwork for understanding consequences of the quantum skyrmion Hall effect
Quantum Optics Applications of Hexagonal Boron Nitride Defects
No full textHexagonal boron nitride (hBN) has emerged as a compelling platform for both classical and quantum technologies. In particular, the past decade has witnessed a surge of novel ideas and developments, which may be overwhelming for newcomers to the field. This review provides an overview of the fundamental concepts and key applications of hBN, including quantum sensing, quantum key distribution, quantum computing, and quantum memory. Additionally, critical experimental and theoretical advances that have expanded the capabilities of hBN are highlighted, in a cohesive and accessible manner. The objective is to equip readers with a comprehensive understanding of the diverse applications of hBN, and provide insights into ongoing research efforts