IYTE GCRIS Database (Izmir Institute of Technology)
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Hydrothermal Synthesis, Characterization and Catalytic Activities of a Keggin Structure of (4,4′-Bpyh2)3[pw12o40]2•3h2o and a Wells-Dawson Structure of (4,4′-Bpyh2)3(4,4′
No full textTwo novel polyoxometalates composed of heteropolytungstates, (4,4 '-bpyH2)3[PW12O40]2 center dot 3H2O (1) and (4,4 '- bpyH2)3(4,4 '-bpyH)1.75[Cu(bpy)2]0.25[H2P2W18O62]2 (2) have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction and TGA methods. Compound 1 crystallizes in the cubic space group Ia-3with a = 25.9356(12) angstrom, b = 25.936(3) angstrom, c = 25.936(3) angstrom, alpha = 90.00, (3= 90.00, gamma= 90.00 and Z = 8, and compound 2 crystallizes in the triclinic space group P-1with a = 13.5194(17) angstrom, b = 22.400(3) angstrom, c = 27.374(4) angstrom, alpha = 79.833(3), (3= 77.439(3), gamma= 80.213(4) and Z = 2. In addition to structural characterization, the catalytic activities of 1 and 2 were determined in hydrolysis reactions. In the catalytic study, starch hydrolysis reactions were performed by using hydrothermal synthesis, and starch was hydrolyzed successfully at 150 degrees C, 5 h, based on the results of Lugol's test, which highest conversion yields above 90 wt.% under optimum reaction conditions. FT-IR analysis and catalyst reusability tests were also performed for each compound. No appreciable loss was observed in activity after five reaction cycles
An Interior Inverse Generalized Impedance Problem for the Modified Helmholtz Equation in Two Dimensions
No full textWe consider the inverse interior problem of recovering the surface impedances of the cavity from sources and measurements placed on a curve inside of it. The uniqueness issue is investigated, and a hybrid method is proposed for the numerical solution. The approach takes advantages of both direct and iterative schemes, such as it does not require an initial guess and has an accuracy of a Newton-type method. Presented numerical experiments demonstrate the feasibility and effectiveness of the approach
A Novel Approach by Combining Fuzzy Ahp and a Simulation Model To Analyze Suitability of Ports for Offshore Wind Farms
No full textThis study presents a comprehensive suitability analysis for assessing the serviceability of existing container ports for offshore wind farms (OWFs) in Turkey, utilizing a combination of fuzzy analytical hierarchy process with Arena simulation modeling. This study is the first comprehensive analysis of offshore wind port infrastructure that integrates a multi-criteria decision making process with an Arena simulation model tailored specifically for existing container ports. The results indicate that technical criteria are deemed most critical, carrying the highest weight (0.563), with expansion potential identified as the most impactful criterion within the technical category. In addition, the study employs the Arena simulation software to forecast the operational workload on the most suitable ports following potential OWF installations
Valorization of Highly Saline Pickle Brine Waste Into Polyhydroxyalkaonate by Mixed Microbial Culture
No full textSustainable and cost-effective polyhydroxyalkaonate (PHA) production could be achieved with integration of using renewable substrates derived from waste feedstock and mixed microbial culture (MMC). This study aimed to investigate the PHA production capacity of highly saline pickle brine waste (PBW). In this context, the impact of sludge retention time (SRT) on enrichment of PHA storing MMC capable of using highly saline PBW and its effect on microbial community structure was studied. Sequencing batch reactors (SBRs) were operated at SRTs of 2, 4 and 6 days using raw PBW. Feast/famine ratios in all SBRs were between 0.03 and 0.09 indicating high PHA- storage capacity at salinity of 14.8 g NaCl/L. Highest PHA productivity was achieved at SRT of 6 days with PHA storage yield of 0.79 g COD-PHA/g COD and PHA content of 74 % (wt). Microbial population analyses revealed that PHA-producer halotolerant Neomegalonema spp. dominated the total biomass with 41 % in SBR-6 whereas halotolerant PHA-storing Paracoccus spp. and Rhodobacter spp. were dominant in SBR-4 and SBR-2. PBW is suggested to be a favorable feedstock as enrichment of halotolerant PHA storing MMC with stable and high PHA productivity was achieved which would be promising for full-scale applications
Effect of Mirna Administration on Non-Small Cell Lung Cancer Cells Studied by Cellular Viability Assay and Atr-Ftir Spectroscopy Combined With Multivariate Data-Analysis
No full textMicroRNAs (miRNAs), small non-coding RNAs, play a significant role in the regulation of gene expression by various mechanisms. Some miRNAs such as hsa-miR-145 (mir145), hsa-let-7a-1 (let7), hsa-miR-155 (mir155), and hsa-miR-29b (mir29b) are expressed at low levels in cancers and associated with proliferation, metastasis, invasion and apoptosis. In the current study, we aimed to investigate the effect of selected synthetic miRNAs and their combinations on the non-small cell lung cancer (NSCLC) cells (A549) by following the cell viability profile and alterations in the cellular biomolecules with biophysical features. After administration of commercial miRNAs and their various combinations to A549 cell line, each group was analyzed with cell viability assay and attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy combined with unsupervised multivariate analysis. Bioinformatics analysis was also performed to detect and to classify the target human genes obtained from the mirDB database. According to the cell viability results, the "mir29b + let7" combination and "mir155" significantly decreased the cancer cell viability whereas the "mir145 + mir29b" and "mir155 + mir145" combinations dramatically increased the cancer cell viability when compared to the control cells. The FTIR data revealed that administration of the "mir155", "mir29b + let7 + mir155", and "mir29b + let7" combinations caused a decrease in the contents of proteins, lipids and nucleic acids in A549 cells. This study suggests that those miRNA combinations might be potential targets for vaccines or miRNA-based therapies that can restore the miRNA activity and thus should be further evaluated to combat lung cancer with miRNA technology
Gypsophila Eriocalyx Roots Inhibit Proliferation, Migration, and Tgf-Β Signaling in Melanoma Cells
No full textObjectives: Melanoma is a highly malignant and serious form of skin cancer. In addition to the standard treatments, complementary approaches, including phytotherapy, are also used to alleviate symptoms and improve patient well-being. This study aims to investigate the anticancer effects of Gypsophila eriocalyx (GE), an endemic species from Türkiye, on melanoma cells. We set out to determine the efficacy of GE in inhibiting melanoma cell proliferation, migration, and growth, and to explore its underlying mechanisms. Methods: We examined the impact of GE on the proliferation of two melanoma cell lines, Malme-3M and SK-MEL-28, and assessed its developmental toxicity in zebrafish embryos. Next, we evaluated GE's influence on colony formation and wound healing in melanoma cells, as well as its ability to induce apoptosis and affect the TGF-β/Smad signaling pathway, by measuring pathway reporter activity and target gene expression. Results: GE inhibited cell proliferation in melanoma cell lines at concentrations 104 to 488 times lower than those required for normal non-malignant L929 fibroblast cells. In zebrafish embryos, GE demonstrated developmental toxicity only at concentrations above 50μg/mL. GE treatment significantly impaired the colony formation and wound healing abilities of melanoma cells, indicating reduced proliferation and migration. Moreover, GE induced apoptosis in melanoma cells and inhibited the TGF-β/Smad signaling pathway, as evidenced by decreased pathway reporter activity and target gene expression. Conclusions: This study highlights the potential of GE as a novel therapeutic agent in melanoma treatment by demonstrating its ability to inhibit tumor growth and progression. © 2024 the author(s), published by De Gruyter, Berlin/Boston
A Selective Bodipy-Based Fluorescent Sensor for the Detection of Cu2+ Ions in Biological and Environmental Samples
No full textIn this study, we present the design, synthesis, and characterization of a 'turn-on' fluorescent probe, BOD-HDZ, for the selective detection of Cu2+ ions in semi-aqueous solutions, environmental samples (water and soil), and MCF-7 cancer cells. BOD-HDZ was synthesized by functionalizing meso-formyl-BODIPY (BOD-ALD) with a 2-hydrazinopyridine, resulting in fluorescence quenching via a photoinduced electron transfer (PET) mechanism. The 1:1 coordination between Cu2+ and the probe was confirmed through Job's plot analysis and 1H NMR spectroscopy, leading to a 210-fold fluorescence enhancement at 515 nm. BOD-HDZ demonstrated exceptional sensing properties, including a rapid response time (1 min), a broad operational pH range (2-12), and high sensitivity with a detection limit of 141 nM
Fast Firing Technique for Martian Regolith Simulant: Advancing Isru Capabilities
No full textIn-Situ Resource Utilization (ISRU) approaches hold significant importance in plans for space colonization. This work explores a different ISRU concept applying fast-firing, a robust and well-known industrial process, to Mars regolith simulant (MGS-1). The fast-fired specimens were compared to the ones obtained by conventional sintered under low heating rates. When the holding time at the firing temperature is longer than 15 min, fast-fired specimens exhibited higher density and flexural strength (> 35 MPa) than conventional sintering. For both processes, the bulk density values and the mechanical properties of the regolith compacts were enhanced with increasing dwell time. This was attributed to higher heating rates changing the densification/crystallization kinetics involving the basalt glass in the regolith composition. Specifically, high heating rate promotes sintering over crystallization. On these bases, fast firing can be considered a potential candidate for ISRU on Mars
The Future of Urban Hierearchy and Zipf Law: Arima and Bats Forecasting
No full textZipf's Law is recognized as a power law which is used to identify the extent and the evolution of the urban hierarchies. The existing studies have mostly adopted a retrospective view by analysing the past patterns. However, we would like to shed a light onto the future trajectories. Therefore, the aim of this study is to investigate the future of Urban Hierarchies and Zipf's Law for the U.S. Metropolitan Statistical Areas (MSA) and the period 1969-2070. Having applied, two forecasting methods; i."ARIMA (Autoregressive Integrated Moving Average)", ii. "BATS (Exponential smoothing state space model Box-Cox transformation, ARMA errors, Trend and Seasonal components)" and the estimation of rank-size rule, we obtained crucial conclusions (Box and Jenkins in: Time series analysis: forecasting and control, Holden-Day, San Francisco, 1970; Box et al. in: Time series analysis: forecasting and control, Wiley, New Jersey, 2016; Kinney in Acc Rev 53:48-60, 1978; Hyndman et al. in R package version 8.24.0, https://cran.r-project.org/web/packages/forecast/forecast.pdf, 2025; De Livera in: Automatic forecasting with a modified exponential smoothing state space framework, Department of Econometrics ; Business Statistics, Monash University (Working Papers 10/10). https://www.monash.edu/business/econometrics-and-business%20statistics/research/publications/ebs/wp10-10.pdf, 2010; De Livera et al. in: Forecasting time series with complex seasonal patterns using exponential smoothing. (Working paper 15/09), Department of Econometrics ; Business Statistics, Monash University. https://robjhyndman.com/papers/ComplexSeasonality.pdf, 2010; De Livera et al. in J Am Stat Assoc 106:1513-1527, 2011). We provide evidence that the Zipf's Law is observed not to hold over the last century and, if existing conditions hold, it is not expected to be valid in the next 50 years. Pareto exponent is found significantly below the Pareto level, historically, currently and prospectively