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The solid-state reaction technique was used to produce polycrystalline Bi1−xBaxFe1−x(Zn1/3Nb2/3)xO3 at different substitutions for x = 0, 0.025 and 0.05 (referred to as BFO, BBFZN25, and BBFZN50, respectively). Both x-ray diffraction and Raman spectroscopy revealed that the substitution did not affect the rhombohedral structure of BFO. However, the substitution did not prevent the formation of a second phase, which was identified as Bi25FeO39. The amount of this impurity phase was extracted through Rietveld refinement and was further corroborated by Mössbauer spectroscopy. Lattice parameters were found to be increased owing to substitution of larger ions on average. The substitution not only had an impact on average crystallite size, microstrain and dislocation density of BFO, but also had a significant effect on its dielectric properties. As a result, the dielectric permittivity was enhanced, with a notable reduction in dielectric loss. In particular, the magnitude of dielectric permittivity for the optimal composition BBFZN25 reached a value of 360 at room temperature (RT), which is much greater than that for pure BFO. This higher dielectric constant may be attributable to the larger average crystallite size. The reduction in dielectric loss, at RT, suggests an improvement in the electrical resistivity of BFO, caused by the reduction of the creation of oxygen vacancies and the generation of Fe2+. The non-formation of Fe2+ was verified through Mössbauer spectroscopy. The remarkable increase in the dielectric constant for BBFZN25 at higher temperatures (T > RT) is attributed to the interfacial polarization occurring at grain–grain boundary and internal barrier layers related to the Bi25FeO39 phase. [ABSTRACT FROM AUTHOR]

This work focuses on a new BiFeO3 (BFO)-based ceramic prepared by co-doping of Zn2+ and Zr4+ at the Fe-site under low concentration (2%). BiFe0.98(Zn1/2Zr1/2)0.02O3 ceramic (BFZZ-02) was synthesized by the solid-state reaction method. X-ray diffraction revealed the good crystalline nature with the formation of impurities (Bi25FeO39 and Bi2Fe4O9). A rhombohedral R3c structure of BFZZ-02 was elucidated using Rietveld refinement. Raman spectroscopy confirmed also the rhombohedrally distorted perovskite structure and displayed the existence of spin-two-phonon interaction at a higher wavenumber range. BFZZ-02 exhibited a significant improvement in dielectric properties compared to pure BFO. A very high dielectric constant value up to approximately 10000 (at 1 kHz) was reached at Neel temperature (TN = 544 K). The room temperature dielectric constant (ε′r) and loss tangent (tan δ) in BFZZ-02 were ∼734 and ∼0.035, respectively. The weak value in tan δ at room temperature, suggested a decrease in leakage current density compared to BFO owing to the reduction of oxygen vacancies and the formation of Fe2+. The nonexistence of Fe2+ was confirmed by Mossbauer spectroscopy. Eventually, the optical bandgap of BFZZ-02 (Eg ≈ 1.87 eV) was found to be reduced compared to BFO and possible reasons were thus evaluated. Such result suggests a strong absorption of visible light suitable for photocatalytic and solar cell applications. [ABSTRACT FROM AUTHOR]

Hajed M Al-Otaibi,1,2 Nabeela Abdullah Al-Abdullah,3 Abdulrahman A Naqru,4 Mohammed A Boukhari,5 Ahmed M Almohaimeed,2 Abdulaziz J Alzhrani6 1Department of Respiratory Therapy, Faculty of Medical Rehabilitation Sciences, King Abdulaziz University, Jeddah, Saudi Arabia; 2Respiratory Therapy Unit, King Abdulaziz University Hospital, King Abdulaziz University, Jeddah, Saudi Arabia; 3Department of Public Health, Faculty of Nursing, King Abdulaziz University, Jeddah, Saudi Arabia; 4Respiratory Therapy Department, Dr. Soliman Fakeeh Hospital, Jeddah, Saudi Arabia; 5Respiratory Therapy Department, Andalusia Group Hospital, Jeddah, Saudi Arabia; 6Respiratory Therapy Department, Bugshan Hospital, Jeddah, Saudi ArabiaCorrespondence: Hajed M Al-Otaibi, Department of Respiratory Therapy, Faculty of Medical Rehabilitation Sciences, King Abdulaziz University, P.O. Box 80200, Jeddah, 21589, Saudi Arabia, Email halotaibi1@kau.edu.saBackground: The use of simulation-based methods for teaching and learning in the education of health professions is increasing, but its prevalence in Saudi Arabia among respiratory therapy programs has yet to be investigated. The purpose of this study is to identify the use of simulation-based learning (SBL) in respiratory therapy programs in Saudi Arabia.Methods: A cross-sectional study was performed by sending Google forms survey via Email to directors of respiratory therapy programs in Saudi Arabia (N=16) to evaluate how each one used simulations as an educational tool.Results: The survey was returned with a total response of 12 out of all 16 program that were initially contacted (75% response rate). Among the respondents, approximately 75% of the programs are using SBL, while high-fidelity simulation is used by all programs. The present data show that 67% of the respiratory therapy programs has a space for simulation within the department, while 33% utilizes institutional simulation centers. For short simulation scenarios, debriefing is not conducted in 67% of the programs. There is acceptance by program directors that simulation hours should be counted towards clinical hours. About 67% of respondent programs have mandatory simulation learning activities, and 100% agree that simulations should be used more. However, lack of training and shortage of staff are among barriers to increase the use of SBL.Conclusion: SBL is commonly used and relatively varied among respiratory therapy programs. However, it requires some improvements in several aspects, including the use of debriefing and increasing the number of properly trained staff.Keywords: respiratory therapy, simulation, debriefing, medical education, Saudi Arabia

This work presents a fundamental investigation of structural, dielectric and vibrational properties of the doped of the classical BaTi0.925(Yb0.5Nb0.5)0.075O3 (BTYN75) with a low amount of antimony Sb5+. The new lead-free ceramic BaTi0.925[Yb0.5(Nb0.8Sb0.2)0.5]0.075O3 (BTYN75-Sb) was prepared using the solid-state reaction method at 1673 K for 4 h. This ceramic was characterized by X-ray diffraction (XRD), and the XRD pattern was fitted with the Rietveld's refinement. The structural analysis of BTYN75-Sb showed the coexistence of Pm3m-cubic symmetry (33%) and P4mm-tetragonal symmetry (67%) at room temperature (RT). The dielectric properties such as dielectric constant (ε′r) and dielectric loss (tan δ) were determined. The dielectric constant was found to be ε′r = 4109 at Tm = 290 K for 1 kHz. Typical relaxor behavior of BTYN75-Sb was observed and characterized with empirical parameters: ΔTm = 4 K and γ = 1.84. Compared with the pure BTYN75, the low amount of antimony Sb5+ resulted in a slight reduction of the dielectric loss (tan δ < 0.042) over a wide temperature range [195–393 K]. The relaxor behavior and the structural properties of BTYN75-Sb were confirmed by Raman spectroscopic measurement. The relaxor BTYN75-Sb may be a promising candidate for several applications at RT and particularly for energy storage. [ABSTRACT FROM AUTHOR]

This work presents a fundamental investigation of structural, dielectric and vibrational properties of the doped of the classical BaTi0.925(Yb0.5Nb0.5)0.075O3 (BTYN75) with a low amount of antimony Sb5+. The new lead-free ceramic BaTi0.925[Yb0.5(Nb0.8Sb0.2)0.5]0.075O3 (BTYN75-Sb) was prepared using the solid-state reaction method at 1673 K for 4 h. This ceramic was characterized by X-ray diffraction (XRD), and the XRD pattern was fitted with the Rietveld's refinement. The structural analysis of BTYN75-Sb showed the coexistence of Pm3m-cubic symmetry (33%) and P4mm-tetragonal symmetry (67%) at room temperature (RT). The dielectric properties such as dielectric constant (ε′r) and dielectric loss (tan δ) were determined. The dielectric constant was found to be ε′r = 4109 at Tm = 290 K for 1 kHz. Typical relaxor behavior of BTYN75-Sb was observed and characterized with empirical parameters: ΔTm = 4 K and γ = 1.84. Compared with the pure BTYN75, the low amount of antimony Sb5+ resulted in a slight reduction of the dielectric loss (tan δ < 0.042) over a wide temperature range [195–393 K]. The relaxor behavior and the structural properties of BTYN75-Sb were confirmed by Raman spectroscopic measurement. The relaxor BTYN75-Sb may be a promising candidate for several applications at RT and particularly for energy storage. [ABSTRACT FROM AUTHOR]

The bacterial antagonists (Bacillus subtilis GB03, B. subtilis QST713, B. subtilis Y1336 and Pantoea agglomerans P10c) and plant defense activators (acibenzolar-S-methyl (ASM), fosetyl aluminium (F-Al), potassium phosphites (PH) and prohexadione-Ca (ProCa)) were evaluated individually and in combination for efficacy in controlling fire blight in Morocco. Under laboratory conditions, on detached blossoms of apple and pear, only biocontrol treatments based on P. agglomerans P10c and their mixture with B. subtilis QST713 showed a significant reduction in the incidence of the disease when compared to other treatments. Under field conditions, both the above mixture of biocontrol agents as well as all other strains were tested alone or combined with plant defense activators using a split-split-plot design. The treatments were applied on the trees at timings based on their modes of action. Results showed that, when used alone, P. agglomerans P10c, B. subtilis QST713, their mixture (1:1), B. subtilis GB03 and B. subtilis Y1336 reduced blossom infection under field conditions by 66, 63.8, 61.7, 64.2, and 53% respectively. For plant defense activators this reduction was 61.5, 56.6, 50 and 49% for ASM, ProCa, F-Al and PH, respectively. On shoots, it ranged from 40 to 80% for biocontrol agents, but for plant defense activators it varied from 46 to 96.5%. Two individual applications of ProCa were the most effective treatment for reducing shoot blight incidence. The combination of plant defense activators and biocontrol agents allowed the highest protection rate against blossom and shoot blight ranging from 76 to 98.2%. The greatest protection was insured by B. subtilis QST713, P. agglomerans P10c or their mixture combined with ASM or ProCa. [ABSTRACT FROM AUTHOR]

Manganese-doped germanium films are model systems for the study of nanospinodal decomposition into Mn-rich nanostructures and its influence on the electronic and magnetic properties. Here we study a film of Ge0.9Mn0.1 forming self-organized nanocolumns perpendicular to a Ge substrate with high resolution scanning transmission electron microscopy combined with electron energy loss spectroscopy, bulk magnetization, and muon spin rotation and relaxation (μSR) measurements. The Mn-rich nanocolumns approximately form a triangular lattice with no detectable Mn atoms in the matrix. We find that they consist of cores surrounded by shells. The combined analysis of bulk magnetization and μSR data enables us to characterize the electronic and magnetic properties of both the cores and shells. We argue that the discovered phase separation of the columns between a core and a shell is relevant for other transition-metal-doped semiconductors. [ABSTRACT FROM AUTHOR]

Light-driven heterogeneous photocatalysis has gained great significance for generating solar fuel; the challenging charge separation process and sluggish surface catalytic reactions significantly restrict the progress of solar energy conversion using a semiconductor photocatalyst. Herein, we propose a novel and feasible strategy to incorporate dihydroxy benzene (DHB) as a conjugated monomer within the framework of urea containing CN (CNU-DHBx) to tune the electronic conductivity and charge separation due to the aromaticity of the benzene ring, which acts as an electron-donating species. Systematic characterizations such as SPV, PL, XPS, DRS, and TRPL demonstrated that the incorporation of the DHB monomer greatly enhanced the photocatalytic CO 2 reduction of CN due to the enhanced charge separation and modulation of the ionic mobility. The significantly enhanced photocatalytic activity of CNU-DHB 15.0 in comparison with parental CN was 85 µmol/h for CO and 19.92 µmol/h of the H 2 source. It can be attributed to the electron-hole pair separation and enhance the optical adsorption due to the presence of DHB. Furthermore, this remarkable modification affected the chemical composition, bandgap, and surface area, encouraging the controlled detachment of light-produced photons and making it the ideal choice for CO 2 photoreduction. Our research findings potentially offer a solution for tuning complex charge separation and catalytic reactions in photocatalysis that could practically lead to the generation of artificial photocatalysts for efficient solar energy into chemical energy conversion.

Abstract: Depression is a common and serious illness that impairs the health of individuals and societies globally. It is associated with a significant economic burden, with productivity losses exceeding $40 billion dollars annually in the United States (U.S.) alone. This project focused on the use of a systematic, data-driven approach to improve the screening rate for depression in an academic, metropolitan cancer center located in North Texas. A multidisciplinary team collaboratively applied Lean Six Sigma education, methods, and tools within oncology and psychiatry clinics to address the increased risk of depression among oncology patients. Improving the standardization of screening and follow-up processes, resulted in a 44% sustained increase in the depression screening and follow-up performance rate. This improvement was verified to be statistically significant through the use of control charts toward the end of the project., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 National Association for Healthcare Quality.)

Objectives: Recent studies investigated the determinants of trail running performance (i.e., combining uphill (UR) and downhill running sections (DR)), while the possible specific physiological factors specifically determining UR vs DR performances (i.e., isolating UR and DR) remain presently unknown. This study aims to determine the cardiorespiratory responses to outdoor DR vs UR time-trial and explore the determinants of DR and UR performance in highly trained runners., Design: Randomized controlled trial., Methods: Ten male highly-trained endurance athletes completed 5-km DR and UR time-trials (average grade: ±8%) and were tested for maximal oxygen uptake, lower limb extensor maximal strength, local muscle endurance, leg musculotendinous stiffness, vertical jump ability, explosivity/agility and sprint velocity. Predictors of DR and UR performance were investigated using correlation and commonality regression analyses., Results: Running velocity was higher in DR vs UR time-trial (20.4±1.0 vs 12.0±0.5km·h -1 , p<0.05) with similar average heart rate (95±2% vs 94±2% maximal heart rate; p>0.05) despite lower average V̇O 2 (85±8% vs 89±7% V̇O 2max ; p<0.05). Velocity at V̇O 2max (vV̇O 2max ) body mass index (BMI) and maximal extensor strength were significant predictors of UR performance (r 2 =0.94) whereas vV̇O 2max , leg musculotendinous stiffness and maximal extensor strength were significant predictors of DR performance (r 2 =0.84)., Conclusions: Five-km UR and DR running performances are both well explained by three independent predictors. If two predictors are shared between UR and DR performances (vV̇O 2max and maximal strength), their relative contribution is different and, importantly, the third predictor appears very specific to the exercise modality (BMI for UR vs leg musculotendinous stiffness for DR)., (Copyright © 2020 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)