IYTE GCRIS Database (Izmir Institute of Technology)
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Bdac: Boundary-Driven Approximations of K-Cliques
No full textClique counts are crucial in applications like detecting communities in social networks and recurring patterns in bioinformatics. Counting k-cliques-a fully connected subgraph with k nodes, where each node has a direct, mutual, and symmetric relationship with every other node-becomes computationally challenging for larger k due to combinatorial explosion, especially in large, dense graphs. Existing exact methods have difficulties beyond k = 10, especially on large datasets, while sampling-based approaches often involve trade-offs in terms of accuracy, resource utilization, and efficiency. This difficulty becomes more pronounced in dense graphs as the number of potential k-cliques grows exponentially. We present Boundary-driven approximations of k-cliques (BDAC), a novel algorithm that approximates k-clique counts without using recursive procedures or sampling methods. BDAC offers both lower and upper bounds for k-cliques at local (per-vertex) and global levels, making it ideal for large, dense graphs. Unlike other approaches, BDAC's complexity remains unaffected by the value of k. We demonstrate its effectiveness by comparing it with leading algorithms across various datasets, focusing on k values ranging from 8 to 50
Utilizing Magnetic Levitation To Detect Lung Cancer-Associated Exosomes
No full textExtracellular vesicles, especially exosomes, have attracted attention in the last few decades as novel cancer biomarkers. Exosomal membrane proteins provide easy-to-reach targets and can be utilized as information sources of their parent cells. In this study, a MagLev-based, highly sensitive, and versatile biosensor platform for detecting minor differences in the density of suspended objects is proposed for exosome detection. The developed platform utilizes antibody-functionalized microspheres to capture exosomal membrane proteins (ExoMPs) EpCAM, CD81, and CD151 as markers for cancerous exosomes, exosomes, and non-small cell lung cancer (NSCLC)-derived exosomes, respectively. Initially, the platform was utilized for protein detection and quantification by targeting solubilized ExoMPs, and a dynamic range of 1-100 nM, with LoD values of 1.324, 0.638, and 0.722 nM for EpCAM, CD81, and CD151, were observed, respectively. Then, the sensor platform was tested using exosome isolates derived from NSCLC cell line A549 and MRC5 healthy lung fibroblast cell line. It was shown that the sensor platform is able to detect and differentiate exosomal biomarkers derived from cancerous and non-cancerous cell lines. Overall, this innovative, simple, and rapid method shows great potential for the early diagnosis of lung cancer through exosomal biomarker detection
Electrocaloric Behaviour of Tape Cast and Grain Oriented Nbt-Kbt Ceramics
No full textWe have investigated the effects of grain orientation and tape casting process on the electrocaloric properties of 0.82Na(0.5)Bi(0.5)TiO(3)-0.18 K0.5Bi0.5TiO3 (0.82NBT-0.18KBT) ceramics at the Morphotropic Phase Boundary (MPB), using direct and indirect measurements. We observe a larger electrocaloric response for the template-free ceramics compared to 7 and 10 wt% template containing ones, suggesting that grain orientation along rhombohedral 100 > does not improve the electrocaloric response. Indirect measurements yielded a large adiabatic temperature change of around 3 K under an electric field of 50 kV/cm, which is significantly higher than 0.9 K reached at a lower electric field of 40 kV/cm using the direct measurement
Effect of Caf2 Additions on the Yield of Az63 Magnesium Chips During Remelting
No full textMagnesium is one of the metals listed in European Union’s critical raw materials list. Primary production of magnesium is a high energy demanding process which raised the necessity of recycling the magnesium alloys in an efficient way. Remelting those scraps under a salt flux consist of chlorides (NaCl, KCl, and MgCl2) and fluorides (CaF2) are a common process however, different alloys might behave differently when it comes to salt-metal-metal oxide interactions. Furthermore, the condition of the salt flux such as dry-mixed or pre-melted (fused) affects the coagulation and metal yield. This work presents results on the effect of CaF2 concentration and pre-melting the salt flux on metal yield during remelting of chips. A yield up to 75% was observed in the case of remelting of chips under a fused salt flux with 5.5% CaF2 concentration
Machine-Learning Assisted Insights Into Cytotoxicity of Zinc Oxide Nanoparticles
No full textZinc oxide nanoparticles (ZnO NPs) are commercially used as an active ingredient or a color additive in foods, pharmaceuticals, sun protection lotions, and cosmetic products. While the use of ZnO NPs in everyday products has not been linked to any serious health issues so far, the scientific evidence generated for their safety is not conclusive and, in most cases, could not be validated further in in vivo settings. To settle controversies arising from inconsistent in vitro findings in previous research focusing on the toxicity ZnO NPs, we combined the results of 25+ independent studies. One way analysis of variance (ANOVA) and classification and regression tree (CART) algorithm were used to pinpoint intrinsic and extrinsic factors influencing cytotoxic potential of ZnO in nanoscale. Particle size was found to have the most significant impact on the cytotoxic potential of ZnO NPs, with 10 nm identified as a critical diameter below which cytotoxic effects were elevated. As expected, strong cell type-, exposure duration- and dose-dependency were observed in cytotoxic response of ZnO NPs, highlighting the importance of assay optimization for each cytotoxicity screening. Our findings also suggested that ≥12 hours exposure to NPs resulted in cytotoxic responses irrespective of the concentration. Considering the cumulative nature of research processes where advances are made through subsequent investigations over time, such meta-analytical approaches are critical to maximizing the use of accumulated data in nano-safety research. © 2024 Institute of Physics Publishing. All rights reserved
Edge-State Rkky Coupling in Graphene Nanoflakes
No full textWe investigate the long-range behavior and size dependence of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in hexagonal and triangular graphene nanoflakes with zigzag and armchair edges. We employ the tight-binding model with exact diagonalization to calculate the RKKY interaction as a function of the distance between magnetic impurities, nanoflake size, and edge geometry. Our findings demonstrate a strong dependency of the RKKY interaction on edge geometry and flake size, with notable changes in the RKKY interaction strength. We further analyze the influence of structural defects on the interaction strength of exchange interactions. © 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved
Abnormally Accumulated Gm2 Ganglioside Contributes To Skeletal Deformity in Tay-Sachs Mice
No full textTay-Sachs Disease is a rare lysosomal storage disorder caused by mutations in the HEXA gene, responsible for the degradation of ganglioside GM2. In addition to progressive neurodegeneration, Tay-Sachs patients display bone anomalies, including kyphosis. Tay-Sachs disease mouse model (Hexa-/-Neu3-/-) shows both neuropathological and clinical abnormalities of the infantile-onset disease phenotype. In this study, we investigated the effects of GM2 accumulation on bone remodeling activity. Here, we evaluated the bone phenotype of 5-month-old Hexa-/-Neu3-/- mice with age-matched control groups using gene expression analysis, bone plasma biomarker analysis, and micro-computed tomography. We demonstrated lower plasma alkaline phosphatase activity and calcium levels with increased tartrate-resistant acid phosphatase levels, indicating reduced bone remodeling activity in mice. Consistently, gene expression analysis confirmed osteoblast reduction and osteoclast induction in the femur of mice. Micro-computed tomography and analysis show reduced trabecular bone volume, mineral density, number, and thickness in Hexa-/-Neu3-/- mice. In conclusion, we demonstrated that abnormal GM2 ganglioside accumulation significantly triggers skeletal abnormality in Tay-Sachs mice. We suggest that further investigation of the molecular basis of bone structure anomalies is necessary to elucidate new therapeutic targets that prevent the progression of bone symptoms and improve the life standards of Tay-Sachs patients
Local Well-Posedness of the Higher-Order Nonlinear Schrödinger Equation on the Half-Line: Single-Boundary Condition Case
No full textWe establish local well-posedness in the sense of Hadamard for a certain third-order nonlinear Schrödinger equation with a multiterm linear part and a general power nonlinearity, known as higher-order nonlinear Schrödinger equation, formulated on the half-line (Formula presented.). We consider the scenario of associated coefficients such that only one boundary condition is required and hence assume a general nonhomogeneous boundary datum of Dirichlet type at (Formula presented.). Our functional framework centers around fractional Sobolev spaces (Formula presented.) with respect to the spatial variable. We treat both high regularity ((Formula presented.)) and low regularity ((Formula presented.)) solutions: in the former setting, the relevant nonlinearity can be handled via the Banach algebra property; in the latter setting, however, this is no longer the case and, instead, delicate Strichartz estimates must be established. This task is especially challenging in the framework of nonhomogeneous initial-boundary value problems, as it involves proving boundary-type Strichartz estimates that are not common in the study of Cauchy (initial value) problems. The linear analysis, which forms the core of this work, crucially relies on a weak solution formulation defined through the novel solution formulae obtained via the Fokas method (also known as the unified transform) for the associated forced linear problem. In this connection, we note that the higher-order Schrödinger equation comes with an increased level of difficulty due to the presence of more than one spatial derivatives in the linear part of the equation. This feature manifests itself via several complications throughout the analysis, including (i) analyticity issues related to complex square roots, which require careful treatment of branch cuts and deformations of integration contours; (ii) singularities that emerge upon changes of variables in the Fourier analysis arguments; and (iii) complicated oscillatory kernels in the weak solution formula for the linear initial-boundary value problem, which require a subtle analysis of the dispersion in terms of the regularity of the boundary data. The present work provides a first, complete treatment via the Fokas method of a nonhomogeneous initial-boundary value problem for a partial differential equation associated with a multiterm linear differential operator. © 2023 Wiley Periodicals LLC
Hybridising Counterurbanisation: Lessons From Japan's Kankeijinko
No full textThis paper examines the discourse and material manifestation of kankeijinko over bar , a phrase used in Japan to describe, primarily, highly mobile groups of urbanities who make regular visits to the countryside. Drawing on Japanese grey literature, secondary data analysis, national-level policy reports and exploratory fieldwork in the northwest of Japan, we argue that the concept of kankeijinko over bar offers a view of rural mobility quite different from more established views of counterurbanisation, at least in the way that it has been captured in the global north. As a concept, kankeijinko over bar invites us to move beyond simple and binary taxonomies of migration and settlement, and destabilizes the notion of rural vitality as being linked to rural populations that are spatially fixed and bounded. Further, the promotion of kankeijinko over bar in policy discourses in Japan has the potential to support new hybrid, fluid and place-based rural lifestyles that contribute to an interconnected global countryside. On the other hand, the discourse of kankeijinko over bar might privilege certain modes of rural mobility and being, circumscribing the potentialities of these mobile groups
Colorimetric Detection of Serum Creatinine on a Miniaturized Platform Using Hue-Saturation Space Analysis
No full textChronic kidney disease (CKD) is a widespread condition with considerable health and economic impacts globally. However, existing methodologies for serum creatinine assessment often involve prolonged wait times and sophisticated equipment, such as spectrometers, hindering real-time diagnosis and care. Innovative solutions like point-of-care (POC) devices are emerging to address these challenges. In this context, there is a recognized need for remote, regular, automated, and low-cost analysis of serum creatinine levels, given its role as a critical parameter for CKD diagnosis and management. This study introduces a miniaturized system with integrated heater elements designed for precise serum creatinine measurement. The system operates based on the Jaffe method and accurate serum creatinine measurement within a microreservoir chip. Smartphone-based image processing using the hue-saturation-value (HSV) color space was applied to captured images of microreservoirs. The creatinine analyses were conducted in serum with a limit of detection of similar to 0.4 mg/dL and limit of quantification of similar to 1.3 mg/dL. Smartphone-based image processing employing the HSV color space outperformed spectrometric analysis for creatinine measurement conducted in serum. This pioneering technology and smartphone-based processing offer the potential for decentralized renal function testing, which could significantly contribute to improved patient care. The miniaturized system offers a low-cost alternative (0.5 per test) associated with CKD diagnosis and management. This innovation could greatly improve access to diagnosis and monitoring of CKD, especially in regions where access to sophisticated laboratory equipment is limited