Aykut Ayca

Dr. Aykut Ayca


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 September 2021 in Ocean Engineering
Verified
Journal Article
Closed access
AAAykut Ayca
Aykut Ayca
PLPatrick J. Lynett
Patrick J. Lynett

19 December 2016 in Journal of Geophysical Research: Oceans
Verified
Journal Article
Closed access
PDF file
AAAykut Ayca
Aykut Ayca
PLPatrick J. Lynett
Patrick J. Lynett

2 May 2016 in Geophysical Research Letters
Verified
Journal Article
Open access
PDF file
NKNikos Kalligeris
Nikos Kalligeris
VSVassilios Skanavis
Vassilios Skanavis
STSasan Tavakkol
Sasan Tavakkol
AAAykut Ayca
Aykut Ayca
HSHoda El Safty
Hoda El Safty
CSCostas Synolakis
Costas Synolakis
Tsunami‐induced coastal currents are spectacular examples of nonlinear and chaotic phenomena. Due to their long periods, tsunamis transport substantial energy into coastal waters, and as this energy interacts with the ubiquitous irregularity of bathymetry, shear and turbulent features appear. The oscillatory character of a tsunami wave train leads to flow reversals, which in principle can spawn persistent turbulent coherent structures (e.g., large vortices or “whirlpools”) that can dominate damage and transport potential. However, no quantitative measurements exist to provide physical insight into this kind of turbulent variability, and no motion recordings are available to help elucidate how these vortical structures evolve and terminate. We report our measurements of currents in Ventura Harbor, California, generated by the 2015 Chilean M8.3 earthquake. We measured surface velocities using GPS drifters and image sequences of surface tracers deployed at a channel bifurcation, as the event unfolded. From the maps of the flow field, we find that a tsunami with a near‐shore amplitude of 30 cm at 6 m depth produced unexpectedly large currents up to 1.5 m/s, which is a fourfold increase over what simple linear scaling would suggest. Coherent turbulent structures appear throughout the event, across a wide range of scales, often generating the greatest local currents.

1 January 2022 in Anti-Cancer Agents in Medicinal Chemistry
Verified
Journal Article
Closed access
PDF file
UCUgur C.YIlmaz
Ugur C.YIlmaz
BBBakiye Goker Bagca
Bakiye Goker Bagca
EKEmin Karaca
Emin Karaca
ADAsude Durmaz
Asude Durmaz
BDBurak Durmaz
Burak Durmaz
OCOzgur Cogulu
Ozgur Cogulu
Background: Grade IV gliomas are classified as glioblastoma (GBM), which is the most malignant brain cancer type. Various genetic and epigenetic mechanisms play a role in the initiation and progression of GBM. MicroRNAs (miRNAs) are small, non-coding RNA molecules that belong to the main epigenetic regulatory RNA class that plays different roles in either physiological or pathological conditions, including GBM pathogenesis regulating expression levels of the target genes. Brain Cancer Stem Cells (BCSCs) are responsible for poor prognosis, including therapy resistance and relapse. Epigenetic regulation mediated by miRNAs is also a critical component of BCSC selfrenewal and differentiation properties. Propolis is a resinous substance collected by honey bees from various plant sources. The flavonoid content of propolis varies depending on the collection region and the extraction method. Although there are studies that include the effects of different originated-propolis on the miRNA expression levels of the glioblastoma cells, the impact on the BCSCs has not been studied yet. Objective: This study aims to evaluate the effects of propolis obtained from Aydın, a city in western Turkey, on miRNA expression levels of BCSCs and GBM cells. Methods: Aydin propolis was dissolved in 60% ethanol, and after evaporation, distilled water was added to prepare the propolis stock solution. The flavonoids content of the Aydin propolis was determined by MS Q-TOF analysis. Commercially obtained U87MG and BCSCs were used as in-vitro brain cancer models. Cytotoxic and apoptotic effects of Aydın propolis were determined via WST-1 assay and Annexin V test, respectively. The miRNA expression profile was investigated using the real-time qRT-PCR method. The fold changes were calculated by the2-ΔΔCt method. The miRNA-mRNA-pathway interactions, including significantly altered miRNAs, were determined using different bioinformatics tools and databases. Results: Quercetin 3-methyl ether was the main component of the Aydin propolis. Aydin propolis did not show significant cytotoxic and apoptotic effects on both GBM and BCSCs up to 2mg/ml concentration. Aydin propolis treatment decreased the expression of nine miRNAs in the U87MG and five miRNAs in the BCSCs. Moreover, ten miRNAs have upregulated from 2.22 to 10.56 folds in propolis treated GBM cells compared to the control group significantly (p<0.05). In the study, the potential roles of two new miRNAs, whose regulations in glioma were not previously defined, were identified. One of them was miR-30d-5p, a novel potential oncomiR in GBM, which was 2.46 folds downregulated in Aydin propolis treated GBM cells. The other one is miR-335-5p, which is a potential tumor suppressor miR in GBM, that was 5.66 folds upregulated in Aydin propolis treated GBM cells. FOXO pathway, its upstream and downstream regulators, and critically neuronal developmental regulators, NOTCH and WNT pathways, were determined as the most deregulated pathways in Aydin propolis treated cells. Conclusion: The determination of the anti-cancer effect of Aydın propolis on the miRNA expression of GBM, especially on cancer stem cells, may contribute to the elucidation of brain cancer genetics by supporting further analyses.

17 December 2019 in Earth Surface Processes and Landforms
Verified
Journal Article
Closed access
PDF file
SSSangyoung Son
Sangyoung Son
PLPatrick Lynett
Patrick Lynett
AAAykut Ayca
Aykut Ayca

1 July 2017 in Journal of Waterway, Port, Coastal, and Ocean Engineering
Verified
Journal Article
Closed access
AKAdam S. Keen
Adam S. Keen
PLPatrick J. Lynett
Patrick J. Lynett
MEMartin L. Eskijian
Martin L. Eskijian
AAAykut Ayca
Aykut Ayca
RWRick Wilson
Rick Wilson
As a result of damage from the 2010 Chile and 2011 Japanese teletsunamis, tsunami risk to small craft marinas along the West Coast of the United States has become an important concern. This paper outlines an assessment tool that can be used to quantify the tsunami damage potential in small craft harbors. The methodology is based on the demand and capacity of a floating dock system and uses a Monte Carlo framework to address the uncertainty of input parameters. Detailed numerical modeling and damage calibration data from recent tsunamis are used to benchmark the approach. Results are provided as fragility curves and give a quantitative assessment of survivability. This tool yields an indication as to the survivability and/or failure of a floating dock system of vessels and floating components/piles subject to tsunami events. The objective of the presented effort is to quickly evaluate whether a floating dock is likely to survive or be destroyed by a particular tsunami scenario.