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Article Citation - WoS: 1Citation - Scopus: 2The Detailed Transseptal Puncture Technique for Optimal Closure in Patients With a Patent Foramen Ovale(Frontiers Media Sa, 2024) Ilkay, Erdogan; Saricam, Ersin; Kacmaz, Fehmi; Yakici, Aysel; Koca, Cigdem; Ozeke, Ozcan; Onal, Mehmet ZulkufBackground The closure of a patent foramen ovale (PFO) using transseptal puncture has particular advantages and disadvantages. Thus, transseptal puncture should be re-evaluated in detail. Aims We aimed to assess the effectiveness of the detailed transseptal puncture technique in patients who underwent PFO closure due to cryptogenic stroke or transient ischemic attack in terms of residual shunts and atrial fibrillation. Methods We prospectively analyzed 144 consecutive patients who underwent PFO closure by the detailed transseptal puncture technique between February 2013 and April 2023 in two centers. All of the patients had a >10 mm long-tunnel PFO. Results The procedural success rate was 100%. However, after the procedure, moderate pericardial effusion developed in one patient (0.7%) and an acute pulmonary embolism related to femoral vein thrombosis was observed in one patient (0.7%) during the first month. Complications related to the procedure were noted in two patients (1.4%) during the first month of follow-up. Residual shunts were observed in 1.4% of cases after PFO closure. Conclusion We demonstrated that the detailed transseptal technique is safe and effective for PFO closure. The detailed transseptal PFO closure technique significantly reduced the risk of atrial fibrillation, and the occurrence of residual shunts was significantly low following the closure.Article Citation - WoS: 31Citation - Scopus: 40Variational Mode Decomposition-Based Radio Frequency Fingerprinting of Bluetooth Devices(Ieee-inst Electrical Electronics Engineers inc, 2019) Aghnaiya, Alghannai; Ali, Aysha M.; Kara, AliRadio frequency fingerprinting (RFF) is based on identification of unique features of RF transient signals emitted by radio devices. RF transient signals of radio devices are short in duration, non-stationary and nonlinear time series. This paper evaluates the performance of RF fingerprinting method based on variational mode decomposition (VMD). For this purpose, VMD is used to decompose Bluetooth (BT) transient signals into a series of band-limited modes, and then, the transient signal is reconstructed from the modes. Higher order statistical (HOS) features are extracted from the complex form of reconstructed transients. Then, Linear Support Vector Machine (LVM) classifier is used to identify BT devices. The method has been tested experimentally with BT devices of different brands, models and series. The classification performance shows that VMD based RF fingerprinting method achieves better performance (at least 8% higher) than time-frequency-energy (TFED) distribution based methods such as Hilbert-Huang Transform. This is demonstrated with the same dataset but with smaller number of features (nine features) and slightly lower (2-3 dB) SNR levels.Article Citation - WoS: 2Citation - Scopus: 22-Ag and Bone Marrow-Targeted Pcl Nanoparticles as Nanoplatforms for Hematopoietic Cell Line Mobilization(Bmc, 2024) Kose, Sevil; Varan, Cem; Onen, Selin; Nemutlu, Emirhan; Bilensoy, Erem; Korkusuz, PetekBackgroundThe use of mobilizing agents for hematopoietic stem cell (HSC) transplantation is insufficient for an increasing number of patients. We previously reported lipid made endocannabinoid (eCB) ligands act on the human bone marrow (hBM) HSC migration in vitro, lacking long term stability to be therapeutic candidate. In this study, we hypothesized if a novel 2-AG-loaded polycaprolactone (PCL)-based nanoparticle delivery system that actively targets BM via phosphatidylserine (Ps) can be generated and validated.MethodsPCL nanoparticles were prepared by using the emulsion evaporation method and characterized by Zetasizer and scanning electron microscopy (SEM). The encapsulation efficiency and release profile of 2-AG were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The presence of cannabinoid receptors (CBRs) in HSCs and monocytes was detected by flow cytometry. Cell morphology and viability were assessed using transmission electron microscopy (TEM), SEM, and the WST-1 viability assay. The migration efficacy of the 2-AG and 2-AG-loaded nanoparticle delivery system on HSCs and HPSCs (TF-1a and TF-1) and monocytes (THP-1) was evaluated using a transwell migration assay.ResultsThe 140-225 nm PCL nanoparticles exhibited an increasing polydispersity index (PDI) after the addition of Ps and 2-AG, with a surface charge ranging from - 25 to -50 mV. The nanoparticles released up to 36% of 2-AG within the first 8 h. The 2-AG-Ps-PCL did not affect cellular viability compared to control on days 5 and 10. The HSCs and monocytes expressed CB1R and CB2R and revealed increased migration to media containing 1 mu M 2-AG-Ps-PCL compared to control. The migration rate of the HSCs toward monocytes incubated with 1 mu M 2-AG-Ps-PCL was higher than that of the monocytes of control. The 2-AG-Ps-PCL formulation provided a real time mobilization efficacy at 1 mu M dose and 8 h time window via a specific CBR agonism.ConclusionThe newly generated and validated 2-AG-loaded PCL nanoparticle delivery system can serve as a stable, long lasting, targeted mobilization agent for HSCs and as a candidate therapeutic to be included in HSC transplantation (HSCT) protocols following scale-up in vivo preclinical and subsequent clinical trials.Article Citation - WoS: 38Citation - Scopus: 48Fixed Points of Modified f-contractive Mappings in Complete Metric-Like Spaces(Hindawi Ltd, 2015) Alsulami, Hamed H.; Karapinar, Erdal; Piri, HosseinWe introduce the notion of modified F-contractive mappings in the setting of complete metric-like spaces and we investigate the existence and uniqueness of fixed point of such mappings. The presented results unify, extend, and improve several results in the related literature.Review Citation - WoS: 75Citation - Scopus: 120Hybrid Blockchain Platforms for the Internet of Things (iot): a Systematic Literature Review(Mdpi, 2022) Alkhateeb, Ahmed; Catal, Cagatay; Kar, Gorkem; Mishra, AlokIn recent years, research into blockchain technology and the Internet of Things (IoT) has grown rapidly due to an increase in media coverage. Many different blockchain applications and platforms have been developed for different purposes, such as food safety monitoring, cryptocurrency exchange, and secure medical data sharing. However, blockchain platforms cannot store all the generated data. Therefore, they are supported with data warehouses, which in turn is called a hybrid blockchain platform. While several systems have been developed based on this idea, a current state-of-the-art systematic overview on the use of hybrid blockchain platforms is lacking. Therefore, a systematic literature review (SLR) study has been carried out by us to investigate the motivations for adopting them, the domains at which they were used, the adopted technologies that made this integration effective, and, finally, the challenges and possible solutions. This study shows that security, transparency, and efficiency are the top three motivations for adopting these platforms. The energy, agriculture, health, construction, manufacturing, and supply chain domains are the top domains. The most adopted technologies are cloud computing, fog computing, telecommunications, and edge computing. While there are several benefits of using hybrid blockchains, there are also several challenges reported in this study.Article Citation - Scopus: 2The Effects of Paddy Cultivation and Microbiota Members on Arsenic Accumulation in Rice Grain(Mdpi, 2023) Ersoy Omeroglu, Esra; Bayer, Asli; Sudagidan, Mert; Ozalp, Veli Cengiz; Yasa, IhsanAccess to safe food is one of the most important issues. In this context, rice plays a prominent role. Because high levels of arsenic in rice grain are a potential concern for human health, in this study, we determined the amounts of arsenic in water and soil used in the rice development stage, changes in the arsC and mcrA genes using qRT-PCR, and the abundance and diversity (with metabarcoding) of the dominant microbiota. When the rice grain and husk samples were evaluated in terms of arsenic accumulation, the highest values (1.62 ppm) were obtained from areas where groundwater was used as irrigation water, whereas the lowest values (0.21 ppm) occurred in samples from the stream. It was observed that the abundance of the Comamonadaceae family and Limnohabitans genus members was at the highest level in groundwater during grain formation. As rice development progressed, arsenic accumulated in the roots, shoots, and rice grain. Although the highest arsC values were reached in the field where groundwater was used, methane production increased in areas where surface water sources were used. In order to provide arsenic-free rice consumption, the preferred soil, water source, microbiota members, rice type, and anthropogenic inputs for use on agricultural land should be evaluated rigorously.Article Citation - WoS: 2Citation - Scopus: 2Perspectives on Monetary Policy and Cost of Capital: Evidence From Turkey(de Gruyter Poland Sp Zoo, 2017) Turguttopbas, NeslihanThe target of monetary policy is generally set as to create an environment of manageable employment and affordable long-term interest rates. However, priorities of central banks may differ depending on economic and financial circumstances of individual countries. Modern approaches to monetary policy transmission can be grouped under two headings, Money View and Credit View. The money view concentrates on interest rates to explain the effects of monetary policy on aggregate spending by creating an interest rate channel. The credit channel transmission approach focuses on the supply of credits by banks following a monetary policy shift in interest rates. In 2010, the Central Bank of Turkey (CBT) developed an interest rate corridor shaped by one-week and overnight repo lending to the financial banks to absorb excessive volatility caused by short-term capital inflows. Under this framework, the CBT implements its monetary policy in two ways; firstly it can alter the interest rates of weekly repo as well as O/N lending rate. Secondly, it can configure the funding structure it provides to the financial intermediaries. In such a framework, the interest rate transmission mechanism has been operated by two benchmark interest rates, one of which is the weighted average of the cost of funds provided by the CBT and the other is the interest rate in Borsa Istanbul (BIST) money market transactions at an overnight maturity. There is a strong co-movement between the interest rates and they are affected by the movements in the CBT lending rate in both directions. Interest rates applied to deposits and loans by banks are affected by the policy rate (CBT Average Funding Rate) and the market rate (BIST O/N Repo Rate).Article Citation - WoS: 6Citation - Scopus: 6Quantitative Lipidomic Analysis of Takotsubo Syndrome Patients' Serum(Frontiers Media Sa, 2022) Karnati, Srikanth; Guntas, Gulcan; Rajendran, Ranjithkumar; Shityakov, Sergey; Hoering, Marcus; Liebisch, Gerhard; Foerster, Carola Y.Takotsubo syndrome (TTS), also known as the transient left ventricular apical ballooning syndrome, is in contemporary times known as novel acute cardiac syndrome. It is characterized by transient left ventricular apical akinesis and hyperkinesis of the basal left ventricular portions. Although the precise etiology of TTS is unknown, events like the sudden release of stress hormones, such as the catecholamines and the increased inflammatory status might be plausible causes leading to the cardiovascular pathologies. Recent studies have highlighted that an imbalance in lipid accumulation might promote a deviant immune response as observed in TTS. However, there is no information on comprehensive profiling of serum lipids of TTS patients. Therefore, we investigated a detailed quantitative lipid analysis of TTS patients using ES-MSI. Our results showed significant differences in the majority of lipid species composition in the TTS patients compared to the control group. Furthermore, the computational analyses presented was able to link the altered lipids to the pro-inflammatory cytokines and disseminate possible mechanistic pathways involving TNF alpha and IL-6. Taken together, our study provides an extensive quantitative lipidome of TTS patients, which may provide a valuable Pre-diagnostic tool. This would facilitate the elucidation of the underlying mechanisms of the disease and to prevent the development of TTS in the future.Article Citation - WoS: 25Citation - Scopus: 39Optimization and Thermal Analysis of Radial Ventilated Brake Disc To Enhance the Cooling Performance(Elsevier, 2022) Jafari, Rahim; Akyuz, RecepVentilated brake discs are preferable to automobile application because of their higher heat dissipation ability than solid discs. The shape, geometry and number of the cooling fins are interested parameters to be investigated to improve the cooling performance of the discs. In the present study, the optimum design of the brake disc with radial vanes is investigated numerically using the Taguchi design of experiments with taking into account nine design parameters. Finite element method is employed to simulate the detailed airflow and temperature distribution in the disc considering adjoined components as pads, rim, tire and dust shield. It has been found that the ventilation gap width has the highest impact on the brake disc cooling. The cooling time of the disc decreases 21% as the ventilation gap increases from 8 mm to 14 mm. In addition, it reduces about 10% with the increment of the channel width between two adjacent vanes (inverse of vane numbers from 43 to 30) and the twist point from 225 mm to 266 mm. In a decreasing order of importance, fin angle, inner and outer diameters of fin, dust shield, bell link and disc material affect the cooling performance of the ventilated disc.Article Citation - WoS: 8Citation - Scopus: 10Evaluation of Ten Open-Source Eye-Movement Classification Algorithms in Simulated Surgical Scenarios(Ieee-inst Electrical Electronics Engineers inc, 2019) Dalveren, Gonca Gokce Menekse; Cagiltay, Nergiz ErcilDespite providing several insights into visual attention and evidence regarding certain brain states and psychological functions, classifying eye movements is a highly demanding process. Currently, there are several algorithms to classify eye movement events which use different approaches. However, to date, only a limited number of studies have assessed these algorithms under specific conditions, such as those required for surgical training programmes. This study presents an investigation of ten open-source eye-movement classification algorithms using the Eye Tribe eye-tracker. The algorithms were tested on the eye-movement records obtained from 23 surgical residents, who performed computer-based surgical simulation tasks under different hand conditions. The aim was to offer data for the improvement of surgical training programmes. According to the results, due to the different classification methods and default threshold values, the ten algorithms produced different results. Considering the fixation duration, the only common event for all of the investigated algorithms, the binocular-individual threshold (BIT) algorithm resulted in a different clustering compared to the other algorithms. Based on the other set of common events, three clusters were determined by eight algorithms (except BIT and event detection (ED)), distinguishing dispersion-based, velocity-based and modified versions of velocity-based algorithms. Accordingly, it was concluded that dispersion-based and velocity-based algorithms provided different results. Additionally, as it individually specifies the threshold values for the eye-movement data, when there is no consensus about the threshold values to be set, the BIT algorithm can be selected. Especially for such cases like simulation-based surgical skill-training, the use of individualised threshold values in the BIT algorithm can be more beneficial in classifying the raw eye data and thus evaluating the individual progress levels of trainees based on their eye movement behaviours. In conclusion, the threshold values had a critical effect on the algorithm results. Since default values may not always be suitable for the unique features of different data sets, guidelines should be developed to indicate how the threshold values are set for each algorithm.
