IYTE GCRIS Database (Izmir Institute of Technology)
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Enhancement of Savonius Wind Turbine Performance Through Blade Optimization
No full textThe objective of this study is to create an innovative blade design that enhances the power efficiency of the Savonius rotors. This is achieved by optimizing the blade shape of the traditional Savonius rotor using the ANSYS Adjoint solver program. The results of the analysis revealed that the total pressure exerted on the optimized shape was 16 times greater than that of the traditional Savonius rotor. To compare performance metrics, the rotor with the optimized blade structure was numerically modeled alongside the traditional and Banesh-type Savonius rotors using the ANSYS Fluent program. The Dynamic Mesh 6DOF method is used in the model domain in order to simulate rotation of the rotor. The rotors were then analyzed in two different configurations: as a single-stage rotor with a phase angle of 0o, and as a three-stage rotor with a phase angle of 60o between each stage while keeping rotor height constant. The optimized blade rotor with 3 stages demonstrated superior performance with a power coefficient of 0.44, outperforming both the Banesh and traditional Savonius rotors, while also displaying power coefficient values 18.9% and 37.5% higher than the Banesh-type Savonius and traditional Savonius rotors, respectively
A Microrna-Regulated Transcriptional State Defines Intratumoral Cd8+t Cells That Respond To Immunotherapy
No full textThe rising incidence of advanced-stage colorectal cancer (CRC) and poor survival outcomes necessitate new and effective therapies. Immune checkpoint inhibitors (ICIs), specifically anti-PD-1 therapy, show promise, yet clinical determinants of a positive response are suboptimal. Here, we identify microRNA-155 (miR-155) as necessary for CD8+ T cell-infiltrated tumors through an unbiased in vivo CRISPR-Cas9 screen identifying functional tumor antigen-specific CD8+ T cell-expressed microRNAs. T cell miR-155 is required for anti-PD-1 responses and for a vital intratumor CD8+ T cell differentiation cascade by repressing Ship-1, inhibiting Tcf-1 and stemness, and subsequently enhancing Cxcr6 expression, anti-tumor immunity, and effector functions. Based on an underlying miR-155-dependent CD8+ T cell transcriptional profile, we identify a gene signature that predicts ICI responses across 12 diverse cancers. Together, our findings support a model whereby miR155 serves as a central regulator of CD8+ T cell-dependent cancer immunity and ICI responses that may be leveraged for future therapeutics
Co-Designing of Public Space for Urban Design Students Using Citizen-Generated Data
No full textThis study describes the co-design process, which includes the citizens' spatial experiences, needs, and wishes, through participatory digital design tools in urban design. The paper draws on a case study for co-design practices for leftover public space; Re-shaping K ; uumlccediluuml;k Park urban void in Bornova, Izmir, Turkey. The methodology used in this study is a further improvement of 'Citizen Design Science' and its tool Qua-Kit (a map-based e-participation tool), which originated from Future Cities Laboratory (FCL) in ETH Zurich. The toolkit allows users to move geometries in given urban spaces and enables non-expert participants to express their ideas for the urban area through design. Departing from conventional urban design approaches, the shaping of the urban realm became a democratic process in which all stakeholders participated as co-designers. The study utilises objective and subjective design data, offering a novel perspective on urban design education and the profession. The educational experiment showed that participants could contribute their experiences and opinions through active design tools and the development process in co-designing public spaces
Optimization of Moving Bed Membrane Bioreactor Process for Improved Water and Nutrient Recovery From Domestic Wastewater
No full textHybridizing moving bed biofilm reactor (MBBR) and membrane bioreactor (MBR) processes has been reported to enhance wastewater treatment performance, but there remains a lack of knowledge on the optimal process configuration for water and nutrient recovery, which is important in the design of the process. This study aims to optimize MBBR+MBR (MBMBR) process configuration in terms of minimizing membrane fouling together with maximizing N;P recovery rather than removal, comparing three different MBMBR configurations under various loadings. The studied configurations were MBBR+MBR, two serially connected MBBRs+MBR, and two serially connected MBBRs+MBR with sludge recycling from the MBR to the second MBBR. In all the configurations, the first MBBR showed high COD removal rates (up to 24 g-COD/m(2).d), whereas nitrification was not detected due to high COD loading. Nitrification rates in the second MBBR reached 0.65 and 0.92 g-NH4+-N/(m(2).d), in the absence and the presence of sludge recycling from the MBR, respectively. Hence, hybridizing suspended and attached growth by applying sludge recycle (last configuration) improved the nitrification rate and process stability. In the MBR, complete nitrification was attained throughout the study, together with increasing N;P recovery due to biomass decay at long SRTs. The serial arrangement of MBBRs may allow for a more economical design, as the attached biomass in the first MBBR increased appreciably (>20 g-SS/m(2)) under high COD loadings. The last configuration gave the best performance in terms of N;P recycling and minimizing membrane fouling among the studied alternatives
Neolithic Introgression of Il23r-Related Protection Against Chronic Inflammatory Bowel Diseases in Modern Europeans
No full textBackground The hypomorphic variant rs11209026-A in the IL23R gene provides significant protection against immune-related diseases in Europeans, notably inflammatory bowel diseases (IBD). Today, the A-allele occurs with an average frequency of 5% in Europe. Methods This study comprised 251 ancient genomes from Europe spanning over 14,000 years. In these samples, the investigation focused on admixture-informed analyses and selection scans of rs11209026-A and its haplotypes. Findings rs11209026-A was found at high frequencies in Anatolian Farmers (AF, 18%). AF later introduced the allele into the ancient European gene-pool. Subsequent admixture caused its frequency to decrease and formed the current southwest-to-northeast allele frequency cline in Europe. The geographic distribution of rs11209026-A may influence the gradient in IBD incidence rates that are highest in northern and eastern Europe. Interpretation Given the dramatic changes from hunting and gathering to agriculture during the Neolithic, AF might have been exposed to selective pressures from a pro-inflammatory lifestyle and diet. Therefore, the protective A-allele may have increased survival by reducing intestinal inflammation and microbiome dysbiosis. The adaptively evolved function of the variant likely contributes to the high efficacy and low side-effects of modern IL-23 neutralisation therapies for chronic inflammatory diseases. Copyright (c) 2025 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
Physics-Based Machine Learning for Modeling of Laminated Composite Plates Based on Refined Zigzag Theory
No full textPhysics-based machine learning techniques have recently gained prominence for their ability to model complex material and structural behavior, particularly in laminated composite structures. This study introduces an innovative approach, being the first to employ physics-informed neural networks (PINNs) in conjunction with refined zigzag theory (RZT) for the stress analysis of laminated composite plates. A multi-objective loss function integrates governing partial differential equations (PDEs) and boundary conditions, embedding physical principles into the analysis. Using multiple fully connected artificial neural networks, called feedforward deep neural networks, tailored to handle PDEs, PINNs are trained using automatic differentiation. This training process minimizes a loss function that incorporates the PDEs governing the underlying physical laws. RZT, particularly suitable for the stress analysis of thick and moderately thick plates, simplifies the formulation by using only seven kinematic variables, eliminating the need for shear correction factors. The capability of the proposed method is validated through several benchmark cases in stress analysis, including 3D elasticity solutions, analytical solutions, and experimental results from a three-point bending test based on displacement measurements reported in the literature. These results show consistent agreement with the referenced solutions, confirming the accuracy and reliability of the proposed method. Comprehensive evaluations are conducted to examine the effects of softcore presence, elastic foundation, various lamination schemes, and differing loading and boundary conditions on the stress distribution in laminated plates
Assessing the Density of Wood in Heritage Buildings’ Elements Through Expedited Semi-Destructive Techniques
No full textFeatured Application: The research presented and justified in this text aims to provide agents involved in the conservation and refurbishment of old timber elements in buildings with a correlation table for interpreting the readings obtained with penetration resistance testing equipment. Historically, wood has been among the main materials used in heritage buildings. However, the species and mechanical properties of these elements are often unknown. This uncertainty complicates safety assessment calculations, aggravated by the natural variability of the wood properties. The aim of this work is to assess the density of wooden elements in service using semi-destructive techniques that retain the integrity of structural elements. This research had two phases. First, penetration resistance tests were carried out on laboratory scale on Pinus sylvestris L. wood samples taken from 18th, 19th, and 20th century heritage buildings in Lisbon, Portugal. Later, a field study was carried out on wooden elements from the same buildings, involving needle penetration, core drilling, and moisture content determination tests. The laboratory test results showed a strong correlation between the needle penetration depth and wood density, with an R2 value of 0.76. The results of the field study indicated that the density estimated by the needle penetration test correlated effectively with the measured density of extracted cores after moisture correction, with an R2 of 0.99. In conclusion, the experimental results confirm that penetration resistance and moisture tests are reliable and practical for estimating wood density under in-service conditions. © 2025 by the authors
The Role of Effective Catalysts for Hydrogen Production: a Performance Evaluation
No full textIn recent years, research on hydrogen (H2) production for alternative and environmentally-benign energy solution as fuel, storage medium and feedstock has been one of the most highly demanded subjects. It aims to reduce the pressures set by carbon dioxide emissions and the depletion of fossil fuel supplies. Nevertheless, largescale H2 production is limited by its high cost and low yield. The distinct photo-electrochemical characteristics of catalysts have shown them to have great promise for enhancing the production of H2. This article presents an updated and comprehensive review of enhanced H2 production using various catalysts in biological, thermochemical, and water-based processes. Various operational parameters (reactor configuration, catalyst dosage, catalyst type, catalyst modification methods, temperature, pH, and inoculum type) are summarized to improve the H2 production performance and reduce the environmental impacts and costs of these processes. For instance, in dark fermentation, biological H2 production is enhanced by 3.2-38 % with certain metal catalysts. Overall, results revealed that catalysts, specifically inorganic catalysts such as iron, nickel, titanium oxide, and silver, have improved the production rate of H2. This review has provided the application fields and working principles of catalysts in different H2 production processes. Finally, we suggested the main concerns that need to be prioritized in the long-term advancement of H2 production using catalysts
Hazard Assesment and Reduction of Nanomaterials
No full textDemir oksit NP`ler çeşitli alanlardaki, özellikle tanı ve tedavi uygulamaları, kullanımları sayesinde biyomedikal araştırmalarda popüler hale gelmiştir. Ancak, yüzey kaplamasız demir oksit NP`ler toksik etkiler gösterebilmektedir. Bu nedenle, bu NP`lerin biyouyumluluklarını optimize ederken işlevselliklerini koruma konusu büyük öneme sahiptir. Bu çalışmada, işlevselleştirilmiş demir oksit NP`lerin sentezi, karakterizasyonu ve hem in vitro hem de in vivo toksisite değerlendirmeleri yapılarak, tıbbi alandaki güvenli kullanımlarını desteklemek amaçlanmıştır. Bu amaçla, çıplak, dekstran-kaplı, askorbik asit-kaplı ve oleik asit-kaplı olmak üzere dört tip demir oksit NP üretilmiş ve Taramalı Elektron Mikroskopi (SEM), Geçirimli Elektron Mikroskopi (TEM), X ışını difraksiyonu (XRD) ve Fourier-dönüşümlü kızılötesi spektroskopisi (FTIR) gibi yöntemler kullanılarak kimyasal ve yapısal bütünlükleri doğrulanmıştır. Çalışmanın sonuçları, IONP'lerin yüzeyini değiştirmek için kullanılan kaplama malzemelerinin hücreler ve partiküller arasındaki etkileşimleri önemli ölçüde etkilediğini göstermiştir. 2 boyutlu (2B) hücre kültürleri, farklılaşmış monolayerler ve sferoidlerde farklı hücreler (HepG2, CaCo-2 ve HEK293) kullanılarak yapılan sitotoksisite çalışmalarına (WST-1, resazurin ve Annexin V) göre dekstran- ve askorbik asit-kaplı IONP`lerin biyoaktivitesi yüzey kaplamasız NP`lere kıyasla önemli ölçüde artırmıştır. Bu çalışmanın bulguları, biyomedikal uygulamalar için daha güvenli ve etkili NP`ler geliştirilmesinde yüzey işlevselleştirmenin kritik bir öneme sahip olduğunu vurgulamaktadır. Sonuç olarak, bu tez, IONParaştırmalarını içeren literatüre katkıda bulunmakta ve öne çıkan tanı ve tedavi yöntemlerinde kullanılmak üzere ileri düzey NP`lerin oluşturulmasına yardımcı olabilecek değerli bilgiler sağlamaktadır.Iron oxide nanoparticles (IONPs) have become popular in biomedical research due to their applicability in various fields, especially therapeutics and diagnostics. However, a significant challenge lies in enhancing their bioactivity while maintaining functionality, since bare IONPs may pose toxic effects. This study aimed to investigate the synthesis, characterization, and in vitro and in vivo toxicity assessment of functionalized IONPs to ensure their safe and sustainable use in medical areas. For this purpose, four different IONPs, bare, dextran-coated, ascorbic acid-coated, and oleic acid-coated IONPs, were produced and characterized using analytical methods such as Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD) and Fourier-Transform Infrared Spectroscopy (FTIR) to evaluate their morphological and compositional features. Next, different cytotoxic responses and cellular internalization levels of synthesized and extensively characterized IONPs were measured using different cell lines (HepG2, Caco-2 and HEK293) and cytotoxicity tests (WST-1, resazurin and Annexin V) with varying levels of complexity (e.g., 2D, 3D and co-culture models). The results of the study showed that coating materials used to modify the surface of IONPs notably affected the interactions between cells and particles. Dextran- and ascorbic acid-coated IONPs significantly improved the bioactivity of these NPs compared to bare ones, which is supported by cytotoxicity studies performed in 2D cell cultures, differentiated monolayers and spheroids. The findings of this study highlight that surface functionalization is crucial in creating safer and more effective IONPs for biomedical applications. In conclusion, this thesis contributes to the factors that play a role in the cytotoxic effects of IONPs and provides valuable perceptions that may aid in the creation of advanced NPs for precise theranostics
Hybrid Silica Aerogels From Bridged Silicon Alkoxides: Ultralow Thermal Conductivity for Low-Temperature Applications
No full textHybrid silica aerogels are promising materials for thermal insulation applications. Highly porous aerogels were synthesized from bridged bis(triethoxysilyl)methane BTEM and triethoxysilane TREOS silicon alkoxides via the sol-gel process. The carbon content in the hybrid aerogels decreased with increasing amounts of TREOS. Crack-free monolith aerogels were synthesized through supercritical drying, which is crucial for thermal and optical investigations. The aerogels are characterized by high BET surface areas ranging from 700 to 1400 m(2)/g, pore volumes between 2.0 and 10.5 cm(3)/g, and a maximum porosity of 95%. The thermal conductivity of the aerogels at room temperature was measured via a hot disk apparatus. The materials exhibited ultralow thermal conductivity, reaching a minimum value of 15 mW/mK. This value ranks among the lowest reported values for silica-based aerogels in the literature. Optical transmittance measurements indicated high transparency, exceeding 80% in the visible region. Therefore, these exceptional properties of low density, high optical transparency, and low thermal conductivity make these materials promising candidates for transparent insulation applications