IYTE GCRIS Database (Izmir Institute of Technology)
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Prevention of Angular Buried Pipe Failures Under Shear Static Loads Using Granular Waste Tires
No full textPipelines play a crucial role in national economies, and therefore, it is essential that they do not get damaged and become non-operational. This study is about the protection of buried pipelines against static loads using granular waste tires. The behavior of the buried pipe was investigated by placing granular waste tires with a diameter of 10-15 mm around it and examining its response to externally applied forces. Additionally, for comparison purposes, these experiments were repeated by placing silty sand around the pipe. The experiments also examined the distance between the laminar box's shear section and the segmented pipe joint, increasing it incrementally. Experiments in the laminar box used granular waste tire and silty sand as backfill for a vertical PE80 gas pipe, with strain gauges and a load cell measuring applied forces. An inclined natural gas pipe is subjected to both the overburden load and lateral pressure increasing with depth, whereas a vertical pipe experiences only the lateral pressure increasing with depth. To simulate the external force applied to a horizontal pipe, a triangularly distributed load is applied, ensuring consistent conditions for both vertical and inclined pipes. Therefore, the pipe used in the experiment was positioned vertically, and the forces acting on the vertically oriented pipe were represented to establish an equivalence for the horizontal configuration of the pipe. As a result, the use of granular waste tires as a backfill material has dampened the externally applied loads on the pipe more effectively compared to silty sand. When the backfill material is silty sand, the load on the pipe begins to take effect within a very short time and with minimal displacement of the movable block due to differences in void ratio.Doğalgaz boruları, ulusal ekonomilerde önemli bir rol oynamaktadır, bu nedenle zarar görmemeleri ve işlevsiz hale gelmemeleri hayati önem taşımaktadır. Bu çalışma, gömülü boru hatlarının statik yükler karşısında granular atık lastikler kullanılarak korunmasını ele almaktadır. Gömülü borunun davranışı, etrafına 10-15 mm çapında granular atık lastikler serilerek ve boruya dışarıdan uygulanan kuvvetlere karşı gösterdiği tepki incelenerek araştırılmıştır. Ayrıca, karşılaştırma yapmak amacıyla bu deneyler boru etrafına siltli kum serilerek tekrarlanmıştır. Deneylerde ayrıca laminar kutunun kayma bölümü ile parçalı boru ek yeri arasındaki mesafe incelenmiş ve kademeli olarak artırılmıştır. Laminar kutuda yapılan deneylerde, dikey konumlandırılmış PE80 doğalgaz borusu için dolgu malzemesi olarak granüler atık lastik ve siltli kum kullanıldı; kuvvetler, gerinim ölçerler ve yük hücresi ile ölçüldü. Eğimli bir doğalgaz borusu, üzerindeki örtü yükü ve derinlikle artan yan basınca maruz kalırken, dikey bir boru yalnızca derinlikle artan yan basınca maruz kalır. Yatay bir boruya uygulanan dış kuvveti simüle etmek için, üçgen yayılı bir yük uygulanır ve bu, hem dikey hem de eğimli borular için tutarlı koşullar sağlar. Bu yüzden deneyde kullanılan boru dikey olarak yerleştirilmiş ve dikey haldeki boruya gelen kuvvetler borunun yatay hali için de sembolize edilerek bir denklik verilmiştir. Sonuç olarak, dolgu malzemesi olarak granüler atık lastik kullanımı, boru üzerine dışarıdan uygulanan yükleri siltli kuma kıyasla daha etkili bir şekilde sönümlemiştir. Boşluk oranı farklılığından dolayı dolgu malzemesi siltli kum olduğunda, boru üzerindeki yük çok kısa bir sürede ve hareketli bloğun minimum yer değiştirmesiyle etkisini göstermeye başlamıştır
Enhancing the Sustainable Protein Extraction Process From Black Cumin Seed Cake Press for Eco-Friendly Protein Supplements
No full textFinding new protein sources is essential to meet the global population’s needs. Nigella sativa (black cumin) seeds and the residual cake left after oil cold pressing contain valuable nutritional compounds, including proteins, phenolics, essential amino acids, and various bioactive compounds. In the literature, the structural characteristics and functional properties of proteins from black cumin seeds have been extensively studied. However, there are limited reports on the use of emerging extraction technologies for extracting soluble proteins from black cumin seed cake press (BCSCP). Therefore, two distinct extraction techniques—microwave (MW) and ultrasonication (US)—were assessed for their effectiveness in extracting soluble proteins from BCSCP. The aim of this study was to investigate the effects of various operational conditions on protein extraction yield and functional properties of proteins extracted from BCSCP. The maximum protein yield (27.04%) was achieved using a 10% solid/liquid ratio (SLR) at 33 °C for a 30-min extraction time with the US extraction technique. After ultrafiltration, the protein yield increased to 33.83%, showcasing the predominance of sarcosine (17.18 g/100 g), glutamine (11.63 g/100 g), and proline (33.46 g/100 g) amino acids. The water-holding capacity (WHC), oil-holding capacity (OHC), foam capacity (FC), and foam stability (FS) of the BCSCP isolate were found to be 5.4 ± 0.3 g/g, 9.4 ± 0.0 g/g, 43.6 ± 6.4%, and 39.0 ± 4.7%, respectively. The study revealed that US is a suitable extraction process for obtaining soluble proteins from BCSCP with favorable functional properties. Further studies are needed to evaluate the bioavailability and health impacts of bioactive peptides in order to develop food applications. © The Author(s) 2024
A Pragmatic Grouping Model for Bone-Only De Novo Metastatic Breast Cancer (MetS Protocol MF22-03)
No full textDe novo metastatic breast cancer (dnMBC) accounts for 3-10% of newly diagnosed cases, with 20-40% presenting as a bone-only metastatic disease, which can achieve survival outcomes exceeding 10 years with multimodal therapy. However, the role of multimodal therapy remains controversial in the guidelines. Objective: This study aims to identify dnBOMBC subgroups to develop a pragmatic staging system for guiding locoregional therapy decisions. Materials and Methods: Data from the MF07-01 phase III randomized trial (2021, median follow-up time (mFT): 40 months (range 1-131)) and the BOMET prospective multi-institutional registry trial (2021, mFT: 34 months (range 25-45)) were combined for analysis, including only patients who presented with bone-only metastases. Exclusion criteria were patients under 18 and those with a history of prior cancer or cancer metastases. Patients with missing data and positive surgical margins were excluded. Out of 770 patients, 589 were included. Survival analyses were first conducted according to molecular subgroups, after which patients were further stratified by hormone receptor status, human epidermal human epidermal growth factor receptor 2 (HER2) status, tumor grade, and clinical T (cT) stage. Group A (GrA) included hormone receptor (HR)-positive, low- or intermediate-grade tumors at any cT; HR-positive, high-grade tumors with cT0-3; or any HER2-positive tumors. Group B (GrB) included HR-positive, high-grade tumors with cT4 disease or any triple-negative (TN) tumors. Results: The hazard of death (HoD) was 43% lower in GrA than in GrB. Median OS was 65 months (39-104) for GrA patients and 44 months (28-72) for GrB patients (HR 0.57, 95% CI 0.41-0.78, p = 0.0003). Primary tumor surgery (PTS) significantly improved OS in GrA patients, regardless of the number of metastases (solitary: HR, 0.375, 95% CI 0.259-0.543, p 0.001; multiple: HR 0.435, 95% CI 0.334-0.615, p 0.001). Conversely, GrB patients did not experience a significant benefit from PTS. Conclusions: This study demonstrates that GrA patients have better OS than GrB patients, and PTS reduces the HoD in GrA patients compared to systemic therapy alone. These findings support using a modified staging system in dnBOBMC to identify patients who may benefit from multimodal therapy including PTS
Applications of Light-Emitting Diodes in Liquid Foods
No full textRecently, there has been increased interest in investigating alternative nonthermal processes to maintain the quality of liquid food products while preserving their nutritional value. Ultraviolet (UV) irradiation technology is one such method and has been widely explored for liquid food products. Low or medium-pressure mercury vapor lamps are used in this technology. Since these lamps contain mercury known to have toxic effects on the human body and the environment [18], the use of light-emitting diodes (LEDs) has become prominent as an ultraviolet light source. LEDs are created using non-toxic semiconductor material, which allows emitting in different wavelengths. Recently, Light Emitting Diode (LED) technology has been emerging as a non-thermal and non-chemical treatment for surface disinfection and preservation of solid and liquid food materials. This chapter emphasizes the application and effectiveness of LEDs of different wavelengths in liquid food processing and storage. © 2025 by Apple Academic Press, Inc
Imbalance in Redox Homeostasis Is Associated With Neurodegeneration in the Murine Model of Tay-Sachs Disease
No full textBackgroundTay-Sachs disease is a neurodegenerative disorder characterized by a build-up of GM2 ganglioside in the brain, which results in progressive central nervous system dysfunction. Our group recently generated Hexa-/-Neu3-/- mice, a murine model with neuropathological abnormalities similar to the infantile form of Tay-Sachs disease. Previously, we reported progressive neurodegeneration with neuronal loss in the brain sections of Hexa-/-Neu3-/- mice. However, the relationship between the severity of neurodegeneration and the imbalance in redox homeostasis was not yet clarified in Hexa-/-Neu3-/- mice. Here, we evaluated whether neurodegeneration is associated with oxidative stress in the tissues and cells of Hexa-/-Neu3-/- mice and neuroglia cells from Tay-Sachs patients.Methods and resultsCell death and oxidative stress-related markers were evaluated in four brain regions and fibroblasts of 5-month-old WT, Hexa-/-, Neu3-/-, and Hexa-/-Neu3-/- mice and human neuroglia cells using Western blot, RT-PCR, and immunohistochemistry analyses. We further analyzed oxidative stress levels in the samples using flow cytometry analyses. We discovered neuronal death, alterations in intracellular ROS levels, and damaging effects of oxidative stress, especially in the cerebellum and fibroblasts of Hexa-/-Neu3-/- mice.ConclusionsOur results showed that alteration in redox homeostasis might be related to neurodegeneration in the murine model of Tay-Sachs Disease. These findings suggest that targeting the altered redox balance and increased oxidative stress might be a rational therapeutic approach for alleviating neurodegeneration and treating Tay-Sachs disease
Hn1 Functions in Protein Synthesis Regulation Via Mtor-Rps6 Axis and Maintains Nucleolar Integrity
No full textHaematological and Neurological Expressed 1 (HN1) is an oncogene for various cancers and previously has been linked with centrosome clustering and cell cycle pathways. Moreover, HN1 has recently been reported to activate mTOR signalling, which is the regulator of ribosome biogenesis and maintenance. We explored the role of HN1 in mTOR signalling through various gain- and loss-of-function experiments using biochemical approaches in different cell lines. We demonstrated for the first time that HN1 is required for nucleolar organiser region (NOR) integrity and function. Immunoprecipitation-based association and colocalization studies demonstrated that HN1 is an important component of the mTOR-RPS6 axis, and its depletion results with reduced mRNA translation in mammalian cancer cell lines. This study also demonstrated that the depletion of HN1 leads to the irregular distribution of nucleolar structures, potentially leading to cell cycle deregulation as reported previously. Accordingly, components of the translation machinery aggregate with a distinct speckled pattern, lose their essential interactions and ultimately impair mRNA translation efficiency when the HN1 is depleted. These results suggest that HN1 is an essential component of the nucleolus, required for ribosome biogenesis as well as global mRNA translation
Periodate-Mediated Cross-Linking for the Preparation of Catechol Conjugated Albumin Nanoparticles Used for in Vitro Drug Delivery
No full textConjugation of serum albumin protein with catechol-containing dopamine molecules provides an alternative method for the preparation of albumin nanoparticles (NPs). A commonly used desolvation method utilizes glutaraldehyde as a cross-linking agent. Here, the catechol cross-linking mechanism is used instead of glutaraldehyde providing advantages to prevent toxicity and an undesirable reaction of glutaraldehyde with cargo molecules. Covalent cross-linking between dopamine conjugated bovine serum albumin (D-BSA) proteins was obtained in the presence of sodium periodate (NaIO4) as an oxidizer. As a result, spherical D-BSA NPs with a uniform size distribution of around 100 nm in diameter and negative zeta potential around -28 mV were prepared. Optimal conditions were reached when a dopamine:IO4 - molar ratio of 2:1, pH 7.4 of the medium, and acetone as the desolvating agent were used. Furthermore, the obtained NPs display antioxidant properties, have rapid biodegradability in the presence of trypsin, and have a high doxorubicin (DOX) loading (9.1%) with a sustainable drug release. DOX loaded D-BSA NPs also caused up to 90% breast cancer cell (MCF-7) death within 24 h. These results show that drug carrying albumin NPs can alternatively be prepared via covalently cross-linked catechol groups and used in drug delivery studies
Integrating QSAR Analysis and Machine Learning To Explore the Antidiabetic Potential of Natural Compounds
No full textThis study explores the antidiabetic potential of 72 natural compounds using molecular descriptors and QSAR modeling combined with machine learning techniques. The dataset includes 11 experimentally obtained compounds and 61 from the literature, characterized by their IC50 values indicating 50% inhibition of α-glucosidase enzyme activity. Molecular descriptors were generated using ChemAxon’s MarvinSketch and PADEL software, narrowing down over 3000 descriptors to 23 relevant features. Statistical analysis revealed significant multicollinearity among variables, necessitating the application of non-linear machine learning models, namely Random Forest and Gradient Boosting. These models demonstrated predictive capabilities with R² values of 0.7751 and 0.8066, respectively, and highlighted molecular weight and the number of heteroatoms in ring structures as critical features influencing IC50 values. Despite the dataset's variability and limited size, the study underscores the potential of integrating QSAR and machine learning approaches to effectively predict the antidiabetic activity of natural compounds. The findings provide valuable insights for advancing computational methods in drug discovery. © 2025 by the authors
Digital Transformation in Leather Color Fastness Evaluation: Computer-Assisted Grey Scale Analysis
No full textLeather is a critical material in the fashion industry, where it is required to meet specific customer demands for color, specifications, and performance, especially regarding color fastness. Traditional methods for assessing color fastness rely on subjective evaluations conducted by professional experts using grey scale standards. However, human evaluation can be inconsistent due to various factors, such as lighting conditions and individual perception. In this study, leather samples were first subjected to expert evaluations and scored using the grey scale system. These evaluations were then compared with color measurement data obtained through a spectrophotometer, which was processed using custom-designed software (written in the Python programming language). This software provided precise grey scale values based on the color measurements, enabling accurate digital assessments. The results of the comparative analysis showed that the computer-assisted grey scale assessment could be completed in a significantly shorter time frame with a minimal margin of error, offering a more reliable and efficient alternative to traditional evaluation methods. This approach not only enhances the accuracy of color assessments but also streamlines the evaluation process in the leather industry
Speciation of Inorganic and Organometallic Arsenic in Various Matrices With a Novel Spme Fiber Functionalized With Iron Nanoparticles Prior To Lc-Icp Determination
No full textA novel SPME-LC-ICP-MS methodology is described for the simultaneous microextraction/speciation/determination of the metabolically critical inorganic and organoarsenic species, namely, As(III), As(V), dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA) in natural waters such as drinking and geothermal waters, and biological fluids such as urine. The novelty of the study stems also from the use of home-made SPME fibers for the extraction process, and from the proposed methodology needing no derivatization step. SPME fibers were prepared with in-tube capillary template approach through the immobilization of iron nanoparticles into agarose matrix. The fibers demonstrated reproducible extraction (10 % RSD), good mechanical strength and good solvent resistivity. The separation of the analytes was realized by HPLC with a strong anion exchange column via gradient elution using different concentrations of (NH4)(2)CO3 (pH 8.50), and the on-line detection of eluted analytes was achieved by ICP-MS. The validity of the proposed methodology was verified via the analysis of certified reference materials (SRM 1643e, Natural Water-Trace Elements, and SRM 2669, Arsenic Species in Frozen Human Urine) and through spike recovery tests. The values of percentage recovery for SRM 2669 were 90.7 % for As(III), 99.8 % for As(V), 93.6 % for DMA, and 85.9 % for MMA. A good correlation was also found between the certified (60.45 mu gL(-1)) and determined (59.00 mu gL(-1)) values for SRM 1643e. Moreover, the speciation capability of the method was demonstrated on various natural waters and biological fluids