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Evaluation of Superconducting Features and Gap Coefficients for Electron-Phonon Couplings Properties of Mgb2 with Multi-Walled Carbon Nanotube Addition
No full textIn this study, the samples are prepared by solid state reaction method at different weight ratios (0-4%). The characterization of materials produced is conducted with the aid of powder X-ray diffraction (XRD), temperature-dependent electrical resistivities (rho-T) and magnetization (M-H) measurements. Moreover, the change in the scattering/breaking of cooper-pairs in the small homogeneous clusters in the superconducting paths with the addition of multi-walled carbon nanotube is also examined by the energy gap coefficients. All the experimental findings show that the weight ratio of wt 2% is observed to be the optimum addition level. The XRD results indicate that the MgB2 material prepared by the optimum level crystallizes better in hexagonal symmetry. The critical current density is found to increase from 1.0 x 10(4) to 2.3 x 10(4)A cm(-2) depending on the increment in the magnetization values. On the other hand, the addition mechanism is noted to degrade slightly the general electrical features, critical transition temperatures, lattice cell constants and crystallite size of MgB2 material. Regardless, although the carbon nanotube addition seems to be negative effect on some general properties, the fundamental characteristic properties (the crystallinity with smoother crystallographic transition, magnetization values, coupling of adjacent layers, degree of broadening and especially formation of effective nucleation centers for the flux pinning ability) improve seriously at the optimum dopant level. Thus, the MgB2 prepared with the optimum carbon nanotube concentration can exhibit higher performance against the magnetic field and current in larger magnetic field strengths applied
Design Optimization of Ultra-Wideband Vivaldi Antenna using Artificial Intelligence
No full textIn this work, computationally efficient design optimization of frequency selective surface (FSS)-loaded ultra-wideband Vivaldi antenna via the use of data-driven surrogate model is studied. The proposed design methodology consists of a multi-layer FSS structure aimed for performance improvement of the Vivaldi design, which makes the design a multi-objective multidimensional optimization problem. For having a fast and accurate optimization process, a data-driven surrogate model alongside the metaheuristic optimizer honeybee mating optimization (HBMO) had been used. The optimally designed antenna had been prototyped and its performance characteristics had been measured. The obtained experimental results are compared with the simulated results of the proposed method. Results show that the obtained FSS-loaded structure has enhanced directivity compared with the design without FSS structure, without any performance losses in the return loss characteristics. The FSS-loaded Vivaldi antenna operates at 2-12 GHz band with a maximum gain of 10 dBi at 10 GHz which makes the design a good solution for RADAR applications. © ACE
Turkey and the Major Powers in the Eastern Mediterranean Crisis from the 2010s to the 2020s
Get PDFThis study investigates the recent Mediterranean disputes involving Turkey with respect to the major powers of the European Union (EU), United States (US), Russia and China. The author maintains that Turkey's position has been determined by its own interests in the region as informed by its relations with the major powers, their vested interests in the disputes, Turkey's maritime foreign policy ideology (Mavi Vatan), its economic and military capabilities and the shifting international system. Turkey is found to regard the EU and the US as supportive of the Greek and Greek Cypriot policies, although the EU countries are somewhat divided on how to show that support. In such a context, Turkey has desired to have Russia and China on its side in the disputes concerning the Eastern Mediterranean, to counterbalance the influence of the US and the EU. This, however, did not come to fruition since Russia and China opted to remain neutral. © 2022 the author(s
Prognostic importance of microvessel density, VEGF expression and perineural invasion in laryngeal cancer treated with adjuvant radiotherapy
No full textBackground and Aims: We aimed to investigate the prognostic importance of the microvessel density (MVD) value, the vascular endothelial growth factor (VEGF) expression, and the presence of perineural invasion (PNI) in laryngeal cancer (LSCC) patients. Methods: Pathological specimens of 62 LSCC patients were assessed for the evaluation of the MVD value, the VEGF expression level, and the presence of PNI of the tumors. The tumor characteristics and prognostic effects of these parameters on local control (LC) and overall survival (OS) were analyzed. Statistical Analysis: Descriptive analyses were done using frequencies for the demographic variables. The survival estimates were calculated by the Kaplan-Meier survival curves. The effects of the parameters on LC and OS were investigated by using the log-rank test comparing the survival rates. Cox regression analysis was used for multivariable analysis. Results: The 5-year LC and OS rates of the 62 LSCC patients were 64.5 and 53.9%, respectively. Twenty-two patients (35.5%) had PNI and the frequency of PNI was higher in the patients with a high-grade disease (P = 0.01). The MVD value was higher in the tumors of older patients (P = 0.035) and was correlated with the VEGF expression (P = 0.009). A higher tumor grade was related to a higher VEGF expression (P = 0.01) and the increase in the VEGF expression was associated with a significant decrease in the OS (P = 0.03). Conclusion: The VEGF expression, the MVD value, and the presence of PNI had no prognostic significance on the LC in the LSCC patients while only the VEGF expression was associated with the OS
Molecularly imprinted polymer nanoparticles for the recognition of ellagic acid
No full textEllagic acid (EA) is one of the bioactive polyphenolic flavonoids found in many fruits. Over the years, various extraction methods have been developed to isolate pure EA from plant samples. These methods, however, have some disadvantages, such as low specificity and selectivity, not easy incorporation into industrial processes, and low-purification efficiency. The present study proposes an approach based on the molecular imprinting technique. We describe the nanoscale production of EA imprinted polymers for the first time. We develop a straightforward, efficient, and environmentally friendly precipitation polymerization method to synthesize molecularly imprinted polymer nanoparticles (nanoMIPs). To increase the affinity of nanoMIPs, we explore molecular interactions between EA and functional monomers before polymerization. The nanoMIPs are successfully synthesized with an excellent yield of 94.5%. The maximum binding capacity is 66.6 and 45.6 μmol/g for EA imprinted and nonimprinted polymers, respectively. Furthermore, in the presence of quercetin, an EA analog, and other compounds in the pomegranate peel extract solution, nanoMIPs selectively retain EA. NanoMIPs will be a valuable analytical tool for separation and sensing applications, especially dispersive solid-phase extraction. © 2022 Wiley Periodicals LLC
Prioritization of Patients With Psychiatric Comorbidities in Vaccination During COVID-19 Pandemic
Get PDFCOVID-19 pandemisinde psikiyatrik komorbiditeleri olan hastaların
aşılamada önceliklendirilmes
Observation of a State X(2600) in the pi(+) pi(-)eta' System in the Process J/psi -> gamma pi(+)pi(-)eta'
No full textBased on (10087±44)×106 J/ψ events collected with the BESIII detector, the process J/ψ→γπ+π-η′ is studied using two largest decay channels of the η′ meson, η′→γπ+π- and η′→ηπ+π-, η→γγ. A new resonance, which we denote as the X(2600), is observed with a statistical significance larger than 20σ in the π+π-η′ invariant mass spectrum, and it has a connection to a structure around 1.5 GeV/c2 in the π+π- invariant mass spectrum. A simultaneous fit on the π+π-η′ and π+π- invariant mass spectra with the two η′ decay modes indicates that the mass and width of the X(2600) state are 2618.3±2.0-1.4+16.3 MeV/c2 and 195±5-17+26 MeV, where the first uncertainties are statistical, and the second systematic. © 2022 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3
Identification of candidate genes in a family with cancer overload by whole-exome sequencing
Get PDFBackground. Approximately 120 out of every 1 million children in the world develop cancer each year. In Turkey, 2500-3000 children are diagnosed with new cancer each year. The causes of childhood cancer have been studied for many years. It is known that many cancers in children, as in adults, cause uncontrolled cell growth, and develop as a result of mutations in genes that cause cancer. Methods. The investigation of family history within this context in the study, a total of 13 individuals consisting of all children and adults in the family were examined using the whole-exome sequencing (WES) with the individuals who were diagnosed with cancer in the family, who were detected to have different cancer profiles, and defined as high risk and to determine the gene or genes through which the disease has developed. Results. At the end of the study, a total of 30 variants with a pathogenic record in the family were identified. A total of 10 pathogenic variants belonging to 8 different genes from these variants have been associated with various cancer risks. Conclusions. A significant scientific contribution has been made to the mechanism of disease formation by studying a family with a high cancer burden and by finding the genes associated with the disease. In addition, by the results obtained, family members with cancer predisposition were selected after a risk analysis conducted in this family, and the necessary examinations and scans were recommended to provide an early diagnostic advantage. © 2022, Turkish National Pediatric Society. All rights reserved
A flux controlled electronically tunable fully floating OTA based memristor emulator
No full textIn this paper, flux controlled high frequency floating/grounded type memristor emulator circuit based on single OTA (Operational Transconductance Amplifier) is introduced by using CMOS technology. The emulator is realized using single OTA, multi output transconductance amplifier, a grounded resistor and a grounded capacitor. The proposed circuit can be configured in both incremental and decremental topology by changing the connections. The proposed circuit has been simulated in LT-Spice using 0.18 μm CMOS parameters at a supply voltage of ± 1.5 V. The memristor characteristics can be electronically tuned by changing the transconductance of the OTAs. In addition, with change of the capacitor value in the proposed circuit, the pinched hysteresis loop observed in the current versus voltage plane can be held at higher frequencies. The proposed emulator circuit performs well up to 20 MHz. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature
The Relationship Between Dietary Intakes and Total Kidney Volume in Patients with Autosomal Dominant Polycystic Kidney Disease Dietary Intake and Polycystic Kidney Volume
Get PDFAim: There is a need to understand autosomal dominant polycystic kidney disease (ADPKD) patients’ dietary habits since dietary interventions may have potential effects on ADPKD. In this study, we aimed to analyze the relationship between dietary nutrient intake and total kidney volume (TKV). Methods: This cross-sectional study was conducted on 54 ADPKD patients recruited from the Nephrology outpatient clinic between June and July 2014. TKV was determined by magnetic-resonance imaging and general characteristics, biochemical and urinary parameters were determined. The nutrient intakes of patients were calculated using the three-day dietary records obtained on three consecutive days. Results: The total kidney-volume median was found to be 1407 mL. Patients’ total dietary energy and protein intakes were 25.8±9.4 kcal/kg, 0.9±0.3 g/kg, respectively. The percentage of carbohydrates, protein, and fat in energy was 49±7%, 14±3%, 37±7%, respectively. The mean intakes of thiamin, riboflavin, B6, calcium, magnesium, and zinc were sufficient, the mean dietary potassium intake was insufficient; and sodium intake was excessive in both sexes. In females, there was a negative but weak correlation between dietary vitamin C intake and TKV. In males, a negative but weak correlation was found between TKV and dietary intake of fiber, water, vitamin B6, vitamin K, magnesium, and iron. Conclusions: Dietary micronutrient intake may affect TKV according to sex. © 2022, Galenos Publishing House. All rights reserved