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The relationship between CMV reactivation, anti-cytokine treatment and mortality in critical COVID-19 patients
No full textObjective: To examine the use of anti-cytokine treatment in critical COVID-19 patients and their association with the frequency of CMV cases, viral load level, and mortality in these patients. Methods: This is a retrospective study. A total of 170 critical and/or intensive care patients with COVID-19 admitted to Hisar Hospital Intercontinental from March 15, 2020, to December 31, 2021 were divided into the use of anti-cytokine treatment group and the no anti-cytokine treatment group. Furthermore, the relationship between CMV reactivation, mortality and anti-cytokine treatment in patients was also examined. Results: A total of 170 critical COVID-19 patients were included in the study, three of them were excluded. One hundred sixty seven were included in the study of which 38 (22.7%) were found to be CMV DNA positive. As an anti-cytokine treatment, it was observed that tocilizumab was used in 53 patients, anakinra was used in 27 patients, and no anti-cytokine treatment was used in 77 patients. CMV positivity in patients treated with anti-cytokines (31.11%) was found to be significantly higher than in patients who were not treated with it (16.88%) (p:0.033). Furthermore, it was determined that anti-cytokine treatment significantly decreased mortality (p: 0.003) and that there was no significant relationship between CMV reactivation and mortality (p: 0.399). Conclusion: Even though CMV reactivation was high in critical COVID-19 patients who received anti-cytokine treatment, decrease in mortality were observed with early diagnosis and effective treatment. Therefore, CMV infection should be considered in patients receiving immunosuppressive treatment
Suitability of Pristine Carbon Nanotube Yarn Tool for Material Removal by Electrical Discharges
No full textHigh-intensity electrical discharges are used in the unconventional technique known as electrical discharge machining (EDM) to machine metals of any hardness. Due to their extraordinary conductivity and strength, carbon nanotubes (CNTs) have recently been explored in EDM too. However, material removal with CNT yarn (CNTY) has not been studied thoroughly. This work advocates the use of a pristine CNTY as an EDM tool. The feasibility is examined through characterization and material removal experiments. The measurements show that the CNTY ( 100 µm) multi-ply tools extend tool life and, therefore, machining time by more than 14 s in the air and nearly 2.5 s in the oil. Other factors that restrict machining include intensified discharges and the shielding effect of the carbide layer formed on the workpiece. © 2022, ASM International.Marmara Üniversitesi, (FEN-C-DRP-100616-0282
On the bands of the Schrodinger operator with a matrix potential
No full textIn this article, we consider the one-dimensional Schrodinger operator L(Q) with a Hermitian periodic mxm matrix potential Q. We investigate the bands and gaps of the spectrum and prove that most of the positive real axis is overlapped by m bands. Moreover, we find a condition on the potential Q for which the number of gaps in the spectrum of L(Q) is finite
Exploring the magnetic dipole moments of TQQqs and TQQss states in the framework of QCD light-cone sum rules
No full textMotivated by the recent observation of the tetraquark T-cc(+), we investigate the magnetic dipole moments of the possible single and double strange partners, T-QQqs and T-QQss, with the spin-parity J(P) = 1(+) by means of the QCD light-cone sum rules. To this end, we model these states as diquark-antidiquark states with different organizations and interpolating currents. The results of magnetic dipole moments obtained using different diquark-antidiquark structures differ from each other, considerably. The magnetic dipole moment is the leading-order response of a bound system to a soft external magnetic field. Therefore, it provides an excellent platform for investigation of the inner structures of hadrons governed by the quark-gluon dynamics of QCD.Iran Science Elites Federation (Saramadan) [ISEF/M/401385]K. Azizi is grateful to Iran Science Elites Federation (Saramadan) for the partial financial support provided under the grant number ISEF/M/401385
Resonance X (3960) as a hidden charm-strange scalar tetraquark
No full textWe investigate features of the hidden charm-strange scalar tetraquark cc¯ss¯ by calculating its spectral parameters and width, and we compare the obtained results with the mass and width of the resonance X(3960) discovered recently in the LHCb experiment. We model the tetraquark as a diquark-antidiquark state X=[cs][c¯s¯] with spin-parities JPC=0++. The mass and current coupling of X are calculated using the QCD two-point sum rules by taking into account various vacuum condensates up to dimension 10. The width of the tetraquark X is estimated via the decay channels X?Ds+Ds- and X??c?(?). The partial widths of these processes are expressed in terms of couplings G, g1, and g2, which describe the strong interactions of particles at the vertices XDs+Ds-, X?c??, and X?c?, respectively. Numerical values of G, g1, and g2 are evaluated by employing the three-point sum rule method. Comparing the results m=(3976±85) MeV and ?X=(42.2±12.0) MeV obtained for parameters of the tetraquark X and experimental data of the LHCb Collaboration, we conclude that the resonance X(3960) can be considered as a candidate to a scalar diquark-antidiquark state. © 2023 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
A novel optimal power flow model for efficient operation of hybrid power networks
No full textIn the power industry, the design of an efficient optimal power flow (OPF) model is one of the important research challenges. This study presents the formulation and solution of the OPF problem in the presence of RESs, VSC-MTDC transmission lines, and FACTS devices, simultaneously. Fuel cost, voltage deviation, and power loss were selected as OPF objectives and optimized with state-of-the-art metaheuristic algorithms such as MFO, BSA, COA, MRFO, TLABC, and FDB-TLABC. Based on the optimization results, FDB-TLABC has obtained the best fuel cost results of 785.5850 /h, and 820.3022 $/h on the IEEE 30-bus power network. Besides, the algorithm reduced voltage deviation and active power loss by 11.76% and 0.52% compared to TLABC which second most successful algorithm, respectively. The experimental results are statistically analyzed using Wilcoxon signed-rank test. The analysis results show that the FDB-TLABC is a robust and powerful method to solve the introduced OPF problem
Investigation of the strange pentaquark candidate P??s?4338?0 recently observed by LHCb
No full textThe recently observed strange pentaquark candidate, P Lambda yso4338 thorn 0, is investigated to provide information about its nature and substructure. To this end, its mass and width through the decay channels P Lambda yso4338 thorn 0 -> J=y Lambda and P Lambda yso4338 thorn 0 -> ric Lambda are calculated by applying two- and three-point QCD sum rules, respectively. The state is considered as a Xi c D over bar meson-baryon molecular structure with spin-parity quantum numbers JP 1/4 1 -. The obtained mass, mP Lambda 2 yso4338 thorn 0 1/4 4338 130 MeV, and width, Gamma P Lambda yso4338 thorn 0 1/4 10.40 1.93 MeV, are consistent with the experimental data within the presented uncertainties. This allows us to assign a Xi c D over bar molecular structure of JP 1/4 1 - for the P Lambda yso4338 thorn 0 state.Iran Science Elites Federation (Saramadan) [ISEF/M/401385]K. A. is thankful to Iran Science Elites Federation (Saramadan) for the partial financial support provided under Grant No. ISEF/M/401385
Optical-microwave sensor for real-time measurement of water contamination in oil derivatives
No full textThis paper presents a novel microwave sensor using optical activation for measuring in real-time the water contamination in crude oil or its derivatives. The sensor is constructed from an end-coupled microstrip resonator that is interconnected to two pairs of identical fractal structures based on Moore curves. Electromagnetic (EM) interaction between the fractal curves is mitigated using a T-shaped microstrip-stub to enhance the performance of the sensor. The gap in one pair of fractal curves is loaded with light dependent resistors (LDR) and the other pair with microwave chip capacitors. The chip capacitors were used to increase the EM coupling between the fractal gaps to realize a high Q-factor resonator that determines the sensitivity of the sensor. Empirical results presented here show that the insertion-loss of the sensor is affected by the change in LDR impedance when illuminated by light. This property is used to determine the amount of water contaminated oil. The sensitivity of the sensor was optimized using commercial 3D EM solver. The measurements were made by placing a 30 mm diameter petri dish holding the sample on top of the sensor. The petri dish was filled up to a height of 10 mm with the sample of water contaminated crude oil, and the measurements were done in the range between 0.76 GHz and 1.2 GHz. The Q-factor of the oil sample with no water contamination was 70 and the Q-factor declined to 20 for 100% contamination. The error in the measurements was less than 0.024%. The sensor has dimensions of 0.127 & lambda;o x 0.127 & lambda;o x 0.004 & lambda;o and represents a new modality. Compared to existing techniques, the proposed sensor is simple to use, readily portable and is more sensitive.Universidad Carlos III de Madrid; European Union [801538]; King Saud University, Riyadh, Saudi Arabia [RSPD2023R699]; Ministerio de Ciencia, Innovacio n y Universidades; Gobierno de Espana (Agencia Estatal de Investigacion, Fondo Europeo de Desarrollo Regional -FEDER-, European Union) [PID2021-127409OB-C31]Dr. M. Alibakhshikenari acknowledges support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid and the Euro-pean Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 801538. The authors also sincerely appreciate funding from Researchers Supporting Project number (RSPD2023R699) , King Saud University, Riyadh, Saudi Arabia. Also, this work was supported by Ministerio de Ciencia, Innovacio ' n y Universidades, Gobierno de Espana (Agencia Estatal de Investigacio ' n, Fondo Europeo de Desarrollo Regional -FEDER-, Eu-ropean Union) under the research grant PID2021-127409OB-C31 CONDOR. Besides above, the Article Processing Charge (APC) was afforded by Universidad Carlos III de Madrid (Read & Publish Agreement CRUE-CSIC 2023)
Optimal Power Flow for Hybrid AC/DC Electrical Networks Configured With VSC-MTDC Transmission Lines and Renewable Energy Sources
No full textThis article presents the single objective optimal power flow (OPF) formulation incorporating both renewable energy sources, and voltage source converter-based multiterminal direct current transmission lines, simultaneously. To solve the formulated OPF problem, powerful metaheuristic optimization algorithms including adaptive guided differential evolution, marine predators algorithm, atom search optimization, stochastic fractal search (SFS), and fitness-distance balance-based SFS (FDB-SFS) are employed. The performance of the algorithms is tested for the minimization of fuel cost, pollutant emissions of thermal generators, voltage deviation, and active power loss in a modified IEEE 30-bus power network. The simulation results give that FDB-SFS achieved the best results on the fuel cost (786.5361 /h), and the fuel cost with emission-carbon tax (820.5991 $/h). In addition, FDB-SFS reduced voltage deviation and active power loss values by 14.2587% and 6.7438% compared to SFS. The nonparametric Wilcoxon and Friedman statistical test results confirmed that FDB-SFS is an effective and robust algorithm that can be used in the optimization of the introduced OPF problem
Numerical Assessment of the Effects of Ductus Arteriosus Closure on Cerebral Blood Flow Rate in Newborn Infants
No full text2023 Medical Technologies Congress, TIPTEKNO 2023 -- 10 November 2023 through 12 November 2023 -- Famagusta -- 195703The physiological changes within a few days after birth is vital importance for health of newborn infants. Ductus arteriosus, which is a vessel connection between aorta and pulmonary arteries, closes in the first day life of term infants. In this study, a lumped-parameter model was used to evaluate change of cerebral blood flow rate due to closure of ductus arteriosus within a 24 hour after birth in term infants. The model includes heart chambers, systemic circulatory system, pulmonary circulatory system and a complete circle of Willis. The cerebral blood flow rate was 122 mL/min in the cardiovascular system model simulating period right after birth and it increased to 151 mL/min in the cardiovascular system model simulating 24th hour after birth. Also, the blood flow rate through internal carotid arteries increased from 47 mL/min to 58 mL/min and the blood flow rate through vertebral arteries increased from 14 mL/min to 17 mL/min. The results showed that the closure of the ductus arteriosus causes cerebral blood flow rate to increase in term infants. © 2023 IEEE