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Four new tetradentate Schiff-base ligands were prepared in situ from the 1 : 2 condensation of 1,3-diaminopropane and either 2-thiazolecarboxaldehyde (L2thiazole), 4-thiazolecarboxaldehyde (L4thiazole), 4-oxazolecarboxaldehyde (L4 oxazole ), or 5-bromopyridine-2-aldehyde (L5Br-pyridine), and complexed with [Fe(NCS) 2 (pyridine) 4 ] to give four monometallic Fe II complexes, [Fe(Lheterocycle)(NCS) 2 ]. Structural characterisation shows the expected octahedral Fe II centres in all cases, with Lheterocycle occupying the equatorial plane and the two thiocyanate ligands trans to each other, resulting in an N 6 coordination sphere. Solid state magnetic measurements showed that the two complexes with the thiazole-based ligands exhibit the beginning of a spin transition above 300 K, with T 1/2 = 350 K for [Fe(L4thiazole)(NCS) 2 ] and 400 K for [Fe(L2thiazole)(NCS) 2 ], whereas the 4-oxazole-based ligand gives [Fe(L4 oxazole )(NCS) 2 ] which remains high spin at all measured temperatures (50-400 K). Interestingly, [Fe(L5Br-pyridine)(NCS) 2 ] crystallised as two solvent-free polymorphs: magnetic measurements on samples with both polymorphs present showed a two step SCO with an abrupt transition at T 1/2 = 245 K assigned to the transition in polymorph A (as this was also seen in a sample of pure polymorph A), and a gradual transition at T 1/2 = 304 K assigned to polymorph B. These findings show that the order of increasing ligand field strength for these heterocycles is 4-oxazole ≪ 5Br-pyridine < 4-thiazole < 2-thiazole.

Introduction: High-fidelity simulation (HFS) provides a high level of interactivity and realistic experience for the learner by means of using full scale computerised patient simulators. It imitates clinical experience in a controlled and safe environment that closely resembles reality. The purpose of this study was to compare the efficacy of HFS versus video-assisted lecture (VAL) based education in enhancing and consolidating retention of skills among undergraduate medical students., Materials and Methods: A randomised controlled trial (RCT) study involving 111 undergraduate medical students was conducted where the competency of skills was assessed by objective structured clinical examination (OSCE) in the first, fourth and seventh/eighth weeks. A cohort of 12-14 students was enrolled for each session. The randomisation of the participants into control (VAL-based teaching) and intervention (HFS-based teaching) groups was achieved by implementing the computer-based random sequence generation method. VAL-based teaching module was a fully interactive face-to-face teaching session where a prerecorded video clip was used. The video clip detailed the diagnosis of tension pneumothorax in an acute medical emergency and its management by performing needle decompression on a high-fidelity patient simulator (METIman). HFS-based teaching module was delivered as a fully interactive hands-on training session conducted on the same METIman to demonstrate the diagnosis of tension pneumothorax in an acute medical emergency and its management by performing needle decompression. OSCE scores were compared as the denominator of learning (enhancement and retention of skills) between two groups who underwent training with either VAL-based or HFS-based teachings. The OSCE assessments were used to evaluate the participants' performance as a group. These scores were used to compare the enhancement and medium-term retention of skills between the groups. The outcome was measured with the mean and standard deviation (SD) for the total OSCE scores for skills assessments. We used General Linear Model two-way mixed ANOVA to ascertain the difference of OSCE marks over assessment time points between the control and the intervention groups. ANCOVA and two-way mixed ANOVA were used to calculate the effect size and the partial Eta squared. p value less than 0.05 was taken to be statistically significant., Results: The two-way mixed ANOVA showed no statistically significant difference in mean OSCE scores between intervention and control groups (p=0.890), although the mean score of the intervention group was better than the control group., Conclusion: Our study demonstrated that HFS was not significantly effective over VAL-based education in enhancing skills and consolidating retention among undergraduate medical students. Further research is needed to determine its suitability for inclusion in the course curriculum considering the cost-effectiveness of implementing HFS that may supplement traditional teaching methods.

Objective: The aim of this study was to identify the number and type of indications for radiographs ordered in a chiropractic teaching clinic in Malaysia., Methods: A cross-sectional retrospective analysis was conducted using the medical health records of new patients who presented to the International Medical University Bukit Jalil teaching clinic for chiropractic care between August 2018 and July 2019. Data about sociodemographic characteristics, region of presenting complaint, radiography ordering rates, and referral indications were collected. We compared indications reported in the patient records with those listed in the International Medical University Chiropractic Clinical Manual. We conducted χ 2 and logistic regression analysis to identify the association between radiography indications and the number of radiographs ordered., Results: Data were collected for 1451 patients (741 [51.1%] women and 700 [48.9%] men). The most common body region for the presenting complaint was the lumbar/pelvic region (39.0%), and the overall radiograph use rate was 2.7%, with the highest number of radiographs for the lumbar spine., Conclusion: For the patient files sampled in this study, the overall radiograph order rate in the International Medical University Bukit Jalil Chiropractic teaching clinic was 2.7%., (© 2021 by National University of Health Sciences.)

Ironsand is an abundant and inexpensive magnetic mineral resource. However, the magnetic properties of unprocessed ironsand are often inadequate for any practical applications. In this work, the applicability of ironsand for use as a component in a soft magnetic composite for large-scale inductive power transfer applications was investigated. After magnetic separation, the chemical, structural and magnetic properties of ironsand sourced from different locations were compared. Differences observed in the DC magnetic properties were consistent with changes in the chemical compositions obtained from X-ray Absorption Near-Edge Spectroscopy (XANES), which suggests varying the titanohematite to titanomagnetite content. Increased content in titanomagnetite and magnetic permeability correlated well with the total Fe content in the materials. The best-performing ironsand with the highest permeability and lowest core losses was used alongside Mn,Zn-Ferrite particles (ranging from ∼100 μm to 2 mm) to fabricate toroid cores with varying magnetic material loading. It was shown that ironsand can be used to replace up to 15 wt.% of the magnetic materials with minimal impact on the composite magnetic performance, thus reducing the cost. Ironsand was also used as a supporting material in a single-rail wireless power transfer system, effectively increasing the power transfer, demonstrating potential applications to reduce flux leakage.

Electrospinning has been used to fabricate ferromagnetic Ni 0. 47Fe 0.53 nanofiber mats that were composed of individual, orientated Ni 0.47 Fe 0.53 nanofibers. The key steps were processing a polyvinylpyrrolidone nanofiber template containing ferric nitrate and nickel acetate metal precursors in Ar at 300°C and then 95% Ar: 5% H 2 at 600°C. The Ni 0.47 Fe 0.53 fibers were nanostructured and contained Ni 0.47 Fe 0.53 nanocrystals with average diameters of ~14 nm. The Ni 0.47 Fe 0.53 ferromagnetic mats had a high saturation magnetic moment per formula unit that was comparable to those reported in other studies of nanostructured Ni 1- x Fe x . There is a small spin-disordered fraction that is typically seen in nanoscale ferromagnets and is likely to be caused by the surface of the nanofibers. There was an additional magnetic contribution that could possibly stem from a small Fe 1- z Ni z O phase fraction surrounding the fibers. The coercivity was found to be enhanced when compared with the bulk material., (Copyright © 2020 Bhugra, Williams, Chong and Nann.)

Photoluminescence (PL) and radioluminescence (RL) measurements were made on NaMgF 3 :Sm before, during and after exposure to high doses of ionising radiation. Magnetic measurements prior to irradiation showed that approximately 10% of the total Sm concentration was in the divalent state. The RL from Sm 3+ was found to increase while the Sm 2+ RL decreased with increasing x-ray dose before reaching steady-state values for high doses. This behaviour is opposite to that previously reported for Sm 3+ and Sm 2+ PL. We show that this apparent discrepancy can be accounted for by a RL model where there is a hole trap, an electron trap, and direct x-ray induced carrier recombination at Sm 2+ and Sm 3+ . Furthermore, a good fit to the dose-dependence of all of the Sm RL emissions can be obtained by assuming that the relevant electron and hole traps are close to Sm 3+ . Our model accounts for F 3 -centre production during irradiation that affects some of the Sm 3+ RL emissions via reabsorption of the RL by the F 3 -centres. Thus, the rate of F 3 -centre production can be conveniently monitored by the RL intensity ratio, I RL (567 nm)/I RL (650 nm). Additionally, the Sm 2+ RL emissions may be expressed as [1.94  ×  I RL (721 nm)]  -  I RL (695 nm) to determine the real-time dose rate, independent of dose history.

Three-dimensional topological insulators are an important class of modern materials, and a strong spin-orbit coupling is involved in making the bulk electronic states very different from those near the surface. Bi 2 Se 3 is a model compound, and 209 Bi NMR is employed here to investigate the bulk properties of the material with focus on the quadrupole splitting. It will be shown that this splitting measures the energy band inversion induced by spin-orbit coupling in quantitative agreement with first-principle calculations. Furthermore, this quadrupole interaction is very unusual as it can show essentially no angular dependence, e.g., even at the magic angle the first-order splitting remains. Therefore, it is proposed that the magnetic field direction is involved in setting the quantization axis for the electrons, and that their life time leads to a new electronically driven relaxation mechanism, in particular for quadrupolar nuclei like 209 Bi. While a quantitative understanding of these effects cannot be given, the results implicate that NMR can become a powerful tool for the investigation of such systems., (Copyright © 2019. Published by Elsevier Inc.)

We report the structural, electrical and thermopower properties of un-doped and Al doped zinc oxide (ZnO) thin films. Al doping was carried out using 25 keV Al+ implantation with 0.1, 1 and 2% Al into ZnO. X-ray diffraction measurements showed that the lattice parameters were larger than the bulk values, which is consistent with the incorporation of Al atoms at interstitials. Al doping increased the electrical conductivity from 100 (Ωcm)-1 in the un-doped ZnO film to 598 (Ωcm)-1 in the 2% Al doped ZnO film. Electron doping by Al resulted in an increase in the carrier concentration and it had an advantageous effect on the mobility where it was highest for 2% doping. The absolute value of the Seebeck coefficient systematically increased for un-doped, 1% and 2% Al doped ZnO films where the room temperature values were -50.8, -60.9 and -66.3 μV/K, respectively. The power factor increased significantly from 2.58 × 10-5 W/mK2 in un-doped ZnO film to 2.63 × 10-4 W/mK2 in 2% Al doped ZnO film. Our results suggest that the ion beam method is a suitable technique to enhance the thermoelectric properties of ZnO.

We report the synthesis, compositional, structural and magnetic properties of permalloy powders prepared using an arc-discharge method under different atmospheres. Ion beam analysis results showed that powder prepared in air had a higher concentration of oxygen than those prepared under nitrogen or argon atmospheres. X-ray diffraction measurements showed that powders prepared in air contained magnetite (Fe3O4) and other phases, while powders prepared under nitrogen or argon predominately contained permalloy. The permalloy powders contained a broad range of particle sizes, and nanoparticles as small as 10 nm were evident from transmission electron microscopy data. The saturation magnetizations were significantly lower for the powders prepared in air than those prepared under nitrogen or argon. This can be attributed to oxidation, where the saturation magnetization is predominately from Fe3O4 for powders made in air. The coercive fields were also significantly larger for powders prepared in air, which is consistent with the powders containing different phases when compared with the permalloy powders. Our results show that permalloy powders can be made in nitrogen and argon, allowing for the production of low oxygen content permalloy powders for device applications. Our results also suggest that the use of an iron anode could result in Fe3O4 powders.

We report on the results from a (75)As nuclear magnetic resonance (NMR) study of the overdoped iron pnictide superconductor CeFeAsO0.8F0.2. We find two As sites with different shifts at temperatures as high as 100 K, which is above the superconducting transition temperature of 39 K, and hence they cannot be attributed to the effect of vortices in the superconducting state as previously suggested (Ghoshray et al 2009 Phys. Rev. B 79 144512). The much larger spin-lattice relaxation rate compared with that found in other pnictides without magnetic rare earth ions, and the temperature dependence of the (75)As NMR shifts for the two central lines, are consistent with the hyperfine coupling from magnetic Ce to As. The low temperature spectra indicate that there are As ions with two different quadrupole splittings. Our findings appear to be consistent with an electronic phase segregation into regions with two different F dopings or the presence of a correlated spatial charge and spin density variations.

Tungsten oxide-organic layered hybrid materials have been studied by infrared and Raman spectroscopy and demonstrate a difference in bonding nature as the length of the interlayer organic "spacer" molecule is increased. Ethylenediamine-tungsten oxide clearly displays a lack of terminal -NH3(+) ammonium groups which appear in hybrids with longer organic molecules, thus indicating that the longer chains are bound by electrostatic interactions as well as or in place of the hydrogen bonding that must be present in the shorter chain ethylenediamine hybrids. The presence of organic molecules between the tungsten oxide layers, compared with the layered tungstic acid H2WO4, shows a decrease in the apical W=O bond strength, as might be expected from the aforementioned electrostatic interaction.