IYTE GCRIS Database (Izmir Institute of Technology)
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Unveiling the Conditioning Correlation in Ex-Situ Catalytic Pyrolysis of Waste Polyolefins Towards Designated Conversion Into Valuable Products
No full textThe ex-situ catalytic pyrolysis of waste polyolefin plastics holds promise for producing aromatics and light olefins, with potential integrations in the low-carbon olefin processing industry for producing ethylene, propylene, butadiene, or aromatic hydrocarbons. Employing ZSM-5(50) zeolite, selected for its substantial specific surface area and total pore volume, facilitated the catalytic pyrolysis of household plastic waste through an exsitu pyrolysis-catalysis approach. This study explored the impact of operating parameters, T 1-T 2- C/P mass ratio, namely pyrolysis temperature, catalytic vapor upgrading temperature, and the catalyst/plastic mass ratio, on pyrolysis product yields and distributions. Higher T 2 benefited gas production, accompanied by a notable decrease in C 4 content in gaseous products. A larger C/P mass ratio provided more active sites for pyrolysis reactions, but higher T 2 induced coke formation on the catalyst, leading to ZSM-5(50) deactivation and inhibiting further gas production. Positive effects of T 2 and the C/P mass ratio were observed for the concentration of BTX in the produced oil. The quadratic fitting was engaged in characterising the reaction conditions. Specifically, the 500 -550 -0.25 run achieved the maximum C 2 yield of 30.3 wt%, the 500 -350 -0.4 run obtained the highest yield of C 3 and C 4 of 75.4 wt%, and the run of 575 -450 -0.25 yielded the highest amount of BTX of 17.2 wt%. These findings provide valuable insights into the designated conditioning of catalytic pyrolysis for plastic waste valorisation
Development of hydrogels via photocrosslinking of wool proteins
No full textYüksek su emme kapasitesine ve doku benzeri özelliklere sahip hidrojeller, yara iyileşmesi için ideal nemli bir ortam sağlamaktadır. Bu çalışma, yara iyileştirme uygulamaları için doğal bir protein olan oksitlenmiş keratin (KTS) ve sentetik bir polimer olan Pluronic F127 bazlı biyoaktif gallik asit (GA) ve karbon noktaları (CD'ler) içeren hibrit hidrojellerin sentezlenmesine odaklanmıştır. KTS ve F127'nin metakrilatlanmış formları (KTSMA ve F127MA) metakrilik anhidrit kullanılarak sentezlenmiş ve fonksiyonelleştirilmiş formlar spektr oskopik yöntemler kullanılarak doğrulanmıştır. KTSMA ve F127MA, kendi kendini destekleyen hidrojeller oluşturmak için Irgacure 2959 fotobaşlatıcı kullanılarak UV ışığı altında çapraz bağlanmıştır. Üç hidrojel hazırlanmıştır: K4 (%4 KTSMA), K7.5 (%7.5 KTSMA) ve KP7.5 (%4 KTSMA + %3.5 F127MA) ve bunların viskoelastik, şişme, bozunma ve morfolojik özellikleri belirlenmiştir. Hücre proliferasyon testleri, tüm hidrojellerin hücre büyümesini desteklediğini göstermiştir. KP7.5 hidrojelleri kararlı mekanik ve bozunma özellikleri sergilemiştir. Karbon noktalar kurkumin ve l-lizin kullanılarak sentezlenmiş ve S. aureus'a karşı ılımlı antibakteriyel özelliklere sahip olduğu gösterilmiştir. Karbon noktaların yapısal ve optik özellikleri karakterize edilmiştir. Çok işlevli hidrojeller, KPGA, KPCD ve KPGACD, GA ve CD'lerin KP7.5 hidrojeline dahil edilmesiyle elde edilmiştir. GA içeren hidrojeller, DPPH testi ile değerlendirildiği üzere kayda değer antioksidan aktivite sergilemiştir. Biyouyumlulukları göz önüne alındığında, bu hidrojeller yara iyileştirme uygulamalarında potansiyel kullanıma sahiptir.Hydrogels, with high water absorption capacity and tissue-like properties, create a moist environment ideal for wound healing. This study focuses on synthesizing bioactive gallic acid (GA) and carbon dots (CDs) containing hybrid hydrogels based on oxidized keratin (KTS), a natural protein, and Pluronic F127, a synthetic polymer for wound healing applications. Methacrylated forms of the KTS and F127 (KTSMA and F127MA) were synthesized using methacrylic anhydride, and the functionalized forms were confirmed using spectroscopic methods. KTSMA and F127MA were cross-linked under UV light using an Irgacure 2959 photoinitiator to form self-standing hydrogels. Three hydrogels were prepared: K4 (4% KTSMA), K7.5 (7.5% KTSMA), and KP7.5 (4% KTSMA + 3.5% F127MA), and their viscoelastic, swelling, degradation and morphological properties were determined. Cell proliferation tests showed that all the hydrogels supported cell growth. KP7.5 hydrogels exhibited robust mechanical and degradation properties. Carbon dots were synthesized using curcumin and l-lysine and shown to have modest antibacterial properties against S. aureus. Their structural and optical properties were characterized. Multifunctional hydrogels, KPGA, KPCD, and KPGACD, were obtained by incorporating GA and the CDs into the KP7.5 hydrogel. GA-containing hydrogels exhibited notable antioxidant activity, as assessed by the DPPH test. Considering their biocompatibility, these hydrogels have potential use in wound healing applications
Bergamot (i>citrus Bergamia/I>), a (poly)phenol-Rich Source for Improving Osteosarcopenic Obesity: a Systematic Review
No full textThis systematic review investigates the potential of bergamot, a polyphenol-rich citrus fruit, in improving osteosarcopenic obesity, a condition characterized by the simultaneous presence of osteoporosis, obesity, and sarcopenia. Bergamot extracts have been suggested to possess several pharmacological properties, including anti-inflammatory and antioxidant effects, which could be useful in the management of age-related diseases and neuromuscular health. The review highlights the promising effects of bergamot extracts on skeletal muscle mass and function, particularly in the context of obesity, metabolic syndrome, osteosarcopenic obesity, and osteoporosis. Furthermore, some studies have shown that bergamot extracts can improve the metabolic balance, endothelial function, and maximal oxygen uptake in athletes, highlighting their potential benefits for skeletal muscle health. Taken together, these results suggest that bergamot extracts, especially those rich in polyphenols, may be a valuable adjunct in the management of osteosarcopenic obesity and other associated clinical conditions involving pro-inflammatory effects on organs and tissues
Synthesis of Oleic Acid - Coated Zinc - Doped Iron Boride Nanoparticles for Biomedical Applications
No full textAlthough various iron-based magnetic materials have been extensively studied in biomedical field for many years, iron boride compounds with interesting chemical and magnetic properties are relatively less explored, and their potential applications are not as widely known. In this study, the synthesis, coating, surface modification, and cytotoxicity tests of the Fe-Zn-B system were presented. Iron boride-based nanoparticles (NPs) containing elemental zinc (Zn) were developed by using a direct chemical synthesis of FeCl3, 3 , ZnCl2 2 and NaBH4, 4 , and investigated for potential use in biomedical applications. Powders having the phases of pure FeB with small amount of elemental Zn were obtained with a uniform morphology and an average particle size of 68 nm. The NPs were then coated with oleic acid (OA) and surface modified with sodium tricitrate, to increase their stability and biocompatibility, and well-dispersed NPs were obtained with sizes below 30 nm. TEM investigations revealed the presence of hybrid clusters with nanoparticle - OA structures, indicating that FeB nanoparticles were stabilized by being embedded in OA clusters, forming both agglomerated sub-micron and free nano-sized structures. Obtained NPs showed ferromagnetic property, with a saturation magnetization of 25.9 emu/g and a low coercivity of 90 Oe. As a result of testing different types of healthy and cancer cell lines with NPs, Zn-doped-FeB@OA NPs exhibited a high biocompatibility. Results suggested that highly biocompatible and magnetic OA-coated Zn-doped FeB particles can be potential candidates for biomedical applications such as medical imaging or drug delivery systems
Governing Authority Through Bureaucracy: Conflicts Over Bureaucratic Cadres and the Rise of Authoritarianism in the Late Ottoman Empire (1908-1913)
No full textThis article presents a historical analysis of how internal power struggles and conflicts among state actors can foster the development of authoritarian systems, particularly when a political network gains exclusive control over the bureaucratic apparatus through its authority over appointments and dismissals. Focusing on the intricate power struggles and factional rivalries surrounding gubernatorial appointments between 1908 and 1913, this article aims to provide an alternative approach to understanding how the Committee of Union and Progress (CUP) became the dominant governing force within the state apparatus, enabling it to pursue an authoritarian agenda
Computational Investigation of Allostery in Nanobody – Antigen Complexes
No full textGelişen, değişen ve dijitalleşen dünyada hesaplamalı biyokimya alanının sunduğu avantajlar birçok araştırmanın bilgisayar ortamına taşınmasını sağlamıştır. Kümülatif bilgi birikimi ile büyüyen bilim dünyasında nanobodilerin tanı ve tedavide sağladığı faydalar ile nanokor-antijen komplekslerinin araştırılması son zamanlarda giderek artmıştır. Bu bağlamda bu çalışmada, nanokor-antijen komplekslerindeki bağlanma bölgeleri dışında kalan önemli bölgeler araştırılarak yapıların iç dinamiklerinde meydana gelen alosterik değişimler ve bu değişimlerin yapılara yansıması yorumlanmıştır. Çalışmada Caplacizumab – von Willebrand Faktör (vWF), Nanokor 87 – NTCP ve Nanokor 2-67 – SARS-CoV-2 Spike protein kompleksleri incelenmiştir. Bu yapılara ek olarak bu kompleks yapıların bir bileşeni olan antijenlere bağlanan diğer moleküller de çalışmanın konuşu olmuştur. Bu incelemelerde bir potansiyel bağlanma bölgesi tahmin uygulaması olan Essential Site Scanning Analysis (ESSA) uygulaması kullanılmıştır. Yapıların bağlanma bölgelerinin analizi z-skor sonuçlarına göre yapılmış olup önemli bölgeler 5'in üzerinde z-skor sonucuna sahip bölgeler olarak belirlenmiştir. Bu çalışmadaki önemli bulgulardan biri de incelenen nanokor, antijen yapılarının birbirleri ile bağlanma bölgeleri dışında da önemli bölgelere sahip olmasıdır. Bağlanma bölgesi dışında bulunan ve moleküllerin iç dinamiklerinde meydana gelen alosterik değişimlerden kaynaklandığı düşünülen bu bölgelerin, gelecekte nanokor – antijen komplekslerinin bağlanma mekanizmalarının açıklanmasına yeni bir bakış açısı sunacağı ve kapsamlı yapısal analizlerin önemini vurgulamaktadır.Functions of biomolecules can be regulated by allostery, where a molecule binds to a site far from the active site of the structure. Recently, nanobodies are promising for disease treatment and imaging. Exploration of the existence of allostery and new potential sites in nanobodies have not yet been studied in detail, and computational approaches help speed up research on allostery in nanobodies. For this aim, three nanobody-antigen complexes, namely Caplacizumab - von Willebrand factor (vWF), Nanobody 87 - NTCP, and Nanobody 2-67 - SARS-CoV-2 Spike, were computationally examined using Essential Site Scanning Analysis (ESSA) method to predict potential binding sites. The default cutoff distance value of ESSA (10 Å) is replaced with a lower (7.3 Å) and a higher (13 Å) cutoff value where the total number of modes is also increased to 20 in the new ESSA. The old and new ESSA are applied to all structures, and the results are compared to each other to better understand the effect of new parameters on the success of ESSA. It is observed that ESSA is improved with the new parameters, and more successful results are obtained when the cutoff value is 7.3 Å, especially in finding essential residues in complementarity-determining regions (CDRs) for the nanobodies studied. The improved ESSA also revealed some other binding sites in the antigens studied where they interact with other proteins and ligands. The improved method in this thesis might help develop antigen-specific new-generation therapeutics and better diagnostic tools
Effect of Urbanization on Groundwater Resources Hydrodynamics and Bearing Capacity: a Case Study From the Bayraklı Region, Izmir, ̇ Türkiye
No full textThe bearing capacity of soil is a critical factor in the design of foundations for civil engineering structures. The bearing capacity depends on soil properties, as well as the location of the water table. A rise in the groundwater level can be dramatic, especially in highly urbanized regions, and can affect the bearing capacity of foundations. In this study, groundwaterlevel fluctuations in a highly urbanized region in Izmir, the third largest city in Türkiye, was monitored over a 1 year period, and ̇ its effect on reducing the bearing capacity, which is not considered in foundation design and construction, was investigated. For this purpose, four observation wells equipped with groundwater data loggers were used to determine the variations in groundwater level over 1 year. Using the Terzaghi approach to calculate the bearing capacity, normalized bearing capacity plots for various foundation width/depth (B/Df) ratios were generated for all four observation wells. Remarkable bearing capacity changes of 10.94, 8.21, 7.62 and 9.29% were observed in four different observation wells (OW-1, OW-3, OW-6 and OW-9, respectively). The study showed that changes in groundwater level in the region caused by urbanization poses a potential risk to the sustainability of previously constructed foundations. © 2024 The Author(s)
Development of Long Distance Free-Space Quantum Key Distribution System
No full textKuantum Anahtar Dağıtımı (KAD), kuantum mekaniğine dayalı prensipleri kullanarak güvenli haberleşme sağlamak amacıyla kullanılan gelişmiş bir yöntemdir. Geleneksel şifreleme yöntemlerinin hesaplama karmaşıklığına dayanmasına karşın, KAD sistemleri birbirlerinden uzak taraflar arasında kriptografik anahtarlar oluşturmak amacıyla kullanmaktadır. KAD sistemleri, tek-foton seviyesinde foton kaynakları tarafından üretilen uçan-kubit durumlarının polarizasyon, faz, yörüngesel açısal momentum vb. gibi fiziksel serbestlik derecelerinin kuantum bilgi işlemesi amacıyla kullanmaktadır. Güvenli iletişim için kullanılan kuantum ışık kaynakları çeşitli yöntemler ile elde edilmektedir. İdeal olarak deterministik olaylarla üretilen tek-foton durumlarının yanı sıra, foton-çifti ve zayıf-tutarlı durumlar gibi nedensel olmayan yöntemler çeşitli senaryolar özelinde öne çıkmaktadır. Bu bağlamda KAD protokollerinin yanında iletişim kanalları (optik fiber, açık-hava ve sualtı) dikkate alındığında, kuantum ışık kaynakları KAD uygulamaları içerisinde farklı avantajlar ve dezavantajlar sunmaktadır. Bu bağlamda, KAD uygulamalarının verimliliği, menzili ve güvenliği, KAD protokolü ve kuantum ışık kaynaklarının seçimi kapsamında belirleyici olmaktadır. Bu tezin kapsamında, zayıf-tutarlı durumlar kullanarak çeşitli mesafelerde ve anahtarlama oranlarında açık-hava dik-olmayan kuantum durumlarının polarizasyon kodlamasına dayanan B92 protokolü gerçekleştirilmiştir.Quantum Key Distribution (QKD) represents an advanced method for achieving secure communication, leveraging principles rooted in quantum mechanics. Unlike traditional encryption methods reliant on computational complexity, QKD utilizes intrinsic quantum mechanical properties to establish cryptographic keys between remote parties. QKD systems operate using flying-qubit states, generated by photon sources at a single-photon level and employing physical degrees of freedom such as polarization, phase, orbital-angular momentum, etc., for quantum information processing. There are various approaches employed to generate photons for secure communication, including on-demand generation of single photons triggered by deterministic events, as well as the use of non-deterministic generation of photon-pair and weak-coherent states, each suitable for specific scenarios. Each type of photon source offers distinct advantages and disadvantages tailored to applications within QKD systems, considering various protocols and transmission channels such as optical fiber, free-space, and underwater. These factors influence the efficiency, range, and security of QKD implementations, guiding the selection of photon sources to optimize performance in diverse operational conditions. In the scope of thesis, B92-protocol based on polarization encoding of non-orthogonal states is performed over various free-space distances and repetition rates utilizing weak-coherent states
Comprehensive Analysis Ofi> Gjb1/I> in Breast Cancer: Its Implications in Survival and Molecular Mechanisms
No full textBackground/Aim: Breast cancer is the leading cause of cancer-related mortality among women worldwide. The connexin (Cx) family, including GJB1 (Cx32), plays complex roles in tumor progression depending on cellular context and cancer subtype. While Cx32 overexpression has been linked to lymph node metastasis, its effects on survival and molecular processes remain unclear. Herein, we aimed to investigate the role of GJB1 in breast cancer by examining its impact on survival and cellular processes in addition to its expression pattern in tumor subtypes, using public datasets. Materials and Methods: We conducted a comprehensive analysis of GJB1 in breast cancer using METABRIC patient dataset, Cancer Cell Line Encylopedia, and other publicly available databases. We examined the association between GJB1 expression and patient survival, performed differential gene expression analysis, and explored gene set enrichment to identify biological processes associated with high GJB1 expression. Results: GJB1 was significantly down-regulated in breast cancer tissues compared to normal tissues. However, patients with high GJB1 expression had significantly poorer survival compared to those with low expression, with the median survival reduced by over 25 months. Gene ontology (GO) analysis revealed that down- regulated genes in the GJB1-high group were enriched in extracellular matrix components and membrane junctions, while up-regulated genes were associated with mitochondrial function and cellular respiration. Conclusion: Our findings suggest a dual role for GJB1 in breast cancer. Although it is generally down-regulated, high GJB1 expression is associated with poorer survival, implying a potential oncogenic role. Further studies are needed to clarify the role of GJB1 in breast cancer and explore its therapeutic implications
The Investigation of the Role of Nf-Κb in the Proliferation and Differentiation of Hacat Cells Containing Cx26 Kid Syndrome Mutations
No full textKeratit-iktiyozis-sağırlık (KID) sendromu, Connexin26 (Cx26) mutasyonlarından kaynaklanan, sağırlık ve görme bozukluklarının yanı sıra palmoplantar keratoderma (avuç içi ve ayak tabanlarında epidermisin kalınlaşması) ile karakterize edilen nadir bir genetik hastalıktır. Cx26 mutasyonları, hücre zarında kontrolsüz molekül geçişine neden olan sürekli açık, hiperaktif yarım kanalların oluşumuna yol açar. Bu durum keratinositlerin proliferasyonu ve farklılaşmasını etkilese de, Cx26 mutasyonlarından kaynaklanan epidermal değişikliklerin altında yatan mekanizmalar henüz bilinmemektedir. Proteomik çalışmalar, Cx26-D50Y KID sendromu mutasyonu içeren HaCaT keratinosit hücre hattında NF-κB sinyal yolağı proteinlerinde zenginleşme olduğunu göstermiştir. Bu nedenle, Cx26 mutant kanallarının NF-κB yolağı aracılığıyla keratinosit proliferasyon ve farklılaşma mekanizmalarını etkileyerek epidermal bozukluklara yol açabileceği hipotez edildi. Hastalarda farklı şiddetlere neden olan Cx26-G45E and Cx26-D50Y mutasyonlarını sürekli olarak ifade eden HaCaT hücrelerinin proliferasyon ve farklılaşma mekanizmaları üzerinde NF-κB sinyal yolağının rolünü araştırdık. G45E ve D50Y hücreleri sırasıyla çekirdekte bulunan en yüksek RelA ve c-Rel sinyallerini gösterdi. Ek olarak, NaSal muamelesi D50Y hücrelerinde erken ve geç apoptoz oranlarını farklı şekilde etkiledi. Dahası, erken ve geç apoptoz oranları karşılaştırıldığında G45E ve D50Y hücreleri ters yönde bir trend gösterdi. Ayrıca, NF-κB inhibisyonu, G45E hücrelerinin proliferasyon oranını azalttı. Son olarak, NaSal muamelesinden sonra G45E hücrelerinde cytokeratin10 protein seviyelerinde farklılıklar görüldü. G45E ve D50Y'de NF-κB, apoptozu farklı mekanizmalarla etkileyebilir ve D50Y'nin apoptoz mekanizmaları üzerinde farklı etkiler gösteriyor olabilir. Ayrıca, NF-κB, G45E'nin proliferasyon ve farklılaşma mekanizmalarını düzenliyor olabilir. KID sendromu için mevcut bir tedavi bulunmamaktadır. Bu nedenle, bu çalışma KID sendromunun moleküler ve hücresel mekanizmalarını anlamak açısından önemlidir.Keratitis-ichthyosis-deafness (KID) syndrome is a rare genetic disease characterized by deafness, visual impairments, and palmoplantar keratoderma. The disease arises from Connexin26 (Cx26) mutations that lead to the formation of hyperactive hemichannels causing uncontrolled molecule transfer across the membrane. Although the uncontrolled molecule transfer affects the proliferation and differentiation of keratinocytes, the exact molecular and cellular mechanisms underlying the epidermal alterations due to Cx26 mutations are not yet known. Previous studies showed enriched NF-κB pathway members in keratinocyte cell line HaCaT containing Cx26-D50Y KID syndrome mutation. Therefore, we hypothesized that Cx26 mutant channels may cause epidermal disorders by affecting keratinocyte proliferation and differentiation mechanisms via NF-kB pathway. We investigated proliferation and differentiation mechanisms of the HaCaT cells that constitutively express the Cx26-G45E and Cx26-D50Y mutations, which cause different severity. G45E and D50Y containing cells showed the highest nuclear RelA and c-Rel signals, respectively. In addition, NaSal treatment affected early and late apoptosis rates differently in D50Y cells. Moreover, G45E and D50Y cells had opposite trends when early and late apoptosis rates were compared. Furthermore, NF-κB inhibition decreased proliferation rate of G45E cells, unlike WT cells. Lastly, cytokeratin10 protein levels showed differences in G45E cells after NaSal treatment. NF-kB may affect apoptosis in KID syndrome mutants through distinct mechanisms and may have different effects on apoptosis mechanisms of D50Y. Furthermore, NF-kB may regulate proliferation and differentiation mechanisms of G45E. There is no available treatment for KID syndrome yet. Therefore, this study is important to understand the underlying mechanisms of KID syndrome