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The critical current density of bulk Bi-2212/MgO whisker composites were measured as a function of microstructural texture. The samples were prepared via different preform processes followed by composite reaction texturing and post-annealing. The measurements showed that c-axis oriented composites containing 10wt% magnesium oxide had the highest Jc values. This indicated the high anisotropy and texture dependence of the composites' critical current density.

A new method of joining ceramic oxide superconductors based on composite reaction texturing is introduced. The technique, which is applicable to both Bi2Sr2CaCu2Ox and RBa2Cu3Ox systems, involves seeding the superconducting phase with a dense and aligned second phase. This is followed by the nucleation of the composite to grow the superconducting phase on the seeds. According to measurements, joints fabricated by this method show critical currents as high as non-joint sections.

The design, fabrication and performance of monolithic Bi2Sr2CaCu2Ox (Bi-2212) conductors for operation with conduction cooling at zero field and a temperature range between four kelvin and 77 K are described. The designs, which were implemented by way of elastomer processing and composite reaction texturing, include current leads with lengths of 10-20 cm., rated currents of 200-1,000 A, thermal conduction losses below 0.05 W and flexural load capacity of over 10 N.

A study on the fabrication of yttrium-barium-copper-oxide superconductors is presented. It tackles the Melt Textured Growth method and the Isothermal Melt Textured approach which improves on the slow cooling and temperature gradient of the former. This enhancement is achieved by capitalizing on the system's melting point being a function of oxygen partial pressure. An experiment to to evaluate such a scheme resulted in superconductors with a large grain microstructure.

This study considers a permutation flow shop-sequencing problem with synchronous transfers between stations. The objective is to minimize the makespan. It is shown that the problem is strongly NP-hard. A branch-and-bound algorithm together with several lower and upper bounding procedures are developed. The algorithm returns optimal solutions to moderate-sized problem instances in reasonable solution times. [ABSTRACT FROM AUTHOR]

The microstructural development of Bi-2212 superconductors fabricated via the Composite Reaction Texturing process is discussed. The study contrasts the fiber alignment of the textured ceramic samples resulting from different whisker alignments. Its results reveal the attainment of high critical current densities, in the order of 2.10x10(super 4) at 4.5 K and 12 T, despite varying material textures.

In today’s higher education institutions in which sustainable development has been highly emphasized, individuals have changed the understanding of graduates of higher education; as such universities have emerged into a reconstruction period. In such a process, universities have been in need of academicians who are well development in both personal and professional domains. The concept of Lifewide learning, which is an important sustainable development tool, has underlined the fact that people should graduate as wholly-developed people to fulfill the needs of future societies, which releases the idea that academicians are to be role models for students. This study reflects on the research designed to develop and test an instrument that could identify the component of an academician’s Lifewide learning habits. Because of the complex nature of the Lifewide learning, considerable attempts were made in order to handle the process of classifying the cognitive, affective, social, technical and cultural domains related to academicians working in faculties of education. The developed instrument was trialled with 50 academicians, and the data was subjected to an explanatory factor analysis, allowing the identification of 6 sub-dimensions of Lifewide learning. These dimensions appeared to be capable of differentiating between problem-solving, professional habits, cultural interaction, leadership, care-based habits and leisure habits of academicians. The final version of the scale was applied to 211 academicians from faculties of education at 30 universities via “Google Drive”, and Lifewide habits of related people were assessed regarding their gender, title and department. Depending on the collected data, Lifewide learning habits of academicians were discussed, and some suggestions were proposed to support their professional and personal development.

Helium ion beam therapy, one of the particle therapies developed and studied in the 1950s for cancer treatment, resulted in clinical trials starting at Lawrence Berkeley National Laboratory in 1975. While proton and carbon ion therapies have been implemented in research institutions and hospitals globally after the end of the trials, progress in comprehending the physical, biological, and clinical findings of helium ion beam therapy has been limited, particularly due to its limited accessibility. Ongoing efforts aim to establish programs that evaluate the use of helium ion beams for clinical and research purposes, especially in the treatment of sensitive clinical cases. Additionally, helium ions have superior physical properties to proton beams, such as lower lateral scattering and larger LET. Moreover, they exhibit similar physical characteristics to carbon, oxygen, and neon ions, which are all used in heavy ion therapy. However, they demonstrate a sharper lateral penumbra with a lower radiobiological absence of certainties and lack the degradation of variations in dose distributions caused by excessive fragmenting of heavier-ion beams, especially at greater depths of penetration. In this context, the status and the prospective advancements of helium ion therapy are examined by investigating ionization, recoil, and lateral scattering values using MC TRIM algorithms in mandible plate phantoms designed from both tissue and previously studied biomaterials, providing an overview for dental cancer treatment. An average difference of 1.9% in the Bragg peak positions and 0.211 mm in lateral scattering was observed in both phantoms. Therefore, it is suggested that the 4 He ion beam can be used in the treatment of mandibular tumors, and experimental research is recommended using the proposed biomaterial mandible plate phantom.

Aim: In our study, we investigated the efficiency of the prognostic nutritional index (PNI) score and the CRP, age, platelet count, albumin level (CAPA) score predicting mortality and intensive care unit (ICU) admission in COVID-19 disease. Materials & methods: PNI and CAPA score of patients confirmed with COVID-19 calculated by using the complete blood count and biochemical parameters at admission to the hospital, in predicting the COVID-19-associated mortality and ICU admission were analyzed. Results: PNI and CAPA scores in predicting mortality were detected as AUC: 0.67 (p < 0.001), AUC: 0.71 (p < 0.001), respectively. For predicting ICU admission AUC was 0.66 (p < 0.001), AUC was 0.77 (p < 0.001), respectively. Conclusion: PNI and CAPA scores are effective scores in COVID-19, with CAPA score being better in predicting mortality and ICU admission.

Background and Aims: Favipiravir is a ribonucleic acid (RNA)-dependent RNA polymerase (RdRP) inhibitor antiviral agent used in the treatment of coronavirus disease-2019 (COVID-19). In this study, we investigated the changes in serum transaminase levels of patients and the relationship between serum transaminase elevation with mortality in patients who were hospitalized with the diagnosis of COVID-19 and received favipiravir treatment., Materials and Methods: 454 patients who received favipiravir and 113 patients who did not receive favipiravir were evaluated. Serum transaminase levels of the patients were compared at baseline and after five days of treatment, and the relationship between serum transaminase elevation and mortality was investigated., Results: No significant aspartate aminotransferase (AST) or alanine aminotransferase (ALT) elevation was detected due to favipiravir treatment. AST elevation was found, respectively, as 133 (29.3%), 32 (28.3%) (p=0.100), ALT elevation as 112 (24.7%), 35 (29.3%) (p=0.100) in the groups receiving and not receiving favipiravir. High AST level was found as a risk factor for mortality in all patient groups (p=0.008)., Conclusions: There was no statistically significant elevation in serum transaminase levels due to favipiravir use in patients hospitalized for COVID-19. A high level of AST is a significant risk factor to show mortality and intensive care unit (ICU) admission in patients with COVID-19., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Bayram et al.)

Objectives: In the present study, it was aimed to study the antioxidant effects of spironolactone (SPL) to determine its possible protective effects in hepatic ischemia reperfusion injury., Material and Methods: Hepatic artery, portal vein, and bile duct of Wistar albino rats were clamped for 45 minutes under anesthesia to form an ischemia period. Then reperfusion was allowed and the rats were decapitated 60 minutes later. SPL (20 mg/kg, p.o.) or SF was orally administered for 30 minutes before ischemia. Rats in the control arm underwent sham surgery and were administered isotonic saline. Liver function was studied by measuring aspartate aminotransferase (AST), alanine aminotransferase (ALT), tumor necrosis factor-alpha (TNF-α), and interleukin 1beta (IL-1β) levels. Malondialdehyde (MDA), glutathione (GSH), luminol, and lucigenin levels, myeloperoxidase (MPO) and Na+-K+-ATPase enzyme activities were analyzed to study tissue injury under light microscope., Results: While IR increased AST, ALT, TNF-α, and IL-1β levels and MDA, luminol, and lusigenin levels and MPO activities, it caused a decrease in GSH levels and Na+K+-ATPase activity. Spironolactone administration significantly improved these values., Conclusion: Protective effects of SPL against ischemia/reperfusion injury via various mechanisms suggest that this agent may become a novel treatment agent in clinical practice., Competing Interests: Conflict of Interest: The authors have no conflicts of interest to declare., (Copyright © 2019, Turkish Surgical Society.)

Objectives: The purpose of this study was to investigate possible protective effects of St. John's wort in the hepatic ischemia/reperfusion injury., Material and Methods: The hepatic artery, portal vein, and bile duct were all clamped for 45 minutes to induce ischemia in rats, and after that reperfusion for 1 hour. SJW was administrated orally, once a day for 3 days before ischemia/reperfusion. The aspartate aminotransferase, alanine aminotransferase, tumor necrosis factor, and interleukin levels were measured in the serum samples. Luminol chemiluminescence, lucigenin luminol chemiluminescence levels; myeloperoxidase. The sodium-potassium ATPase (Na+/K+ ATPase) activity was determined in the liver tissue, and caspase-3 and caspase-9 activity with the bcl-2/bax ratio were measured by the western blot analysis., Results: The St. John's wort administration recovered the aspartate aminotransferase, alanine aminotransferase, tumor necrosis factor, and IL-1β levels serum parameters meaningfully, while ischemia/reperfusion caused an increase in luminol chemiluminescence, lucigenin luminol chemiluminescence, myeloperoxidase, caspase-3, and caspase-9 activity and led to a decrease in the B-cell lymphoma-2/bcl-2-associated X protein (bcl-2/bax) ratio and the Na+/K+ ATPase activity., Conclusion: The obtained results indicate protective effects of St. John's wort on the ischemia/reperfusion injury through various mechanisms, and we are able to suggest that St. John's wort can clinically create a new therapeutic principle.

We demonstrate an optical element for generation of accelerating Airy beams. The element is conveniently constructed by combination of positive and negative cylindrical lenses of matching radii of curvature. With proper choice of lens curvatures, the resulting surface profile closely follows a cubic polynomial. Passing a gaussian beam through this element and performing optical Fourier transform yields beam profiles close to the Airy function. Our experiments demonstrate parabolic propagation, or acceleration, of the resulting focal spots.