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We report on temperature-dependent broadband ferromagnetic resonance studies of magnetite (Fe3O4) film of thickness 30 nm grown on magnesium gallate [MgGa2O4(001)] single crystal substrate by pulsed laser deposition. The isotropic point, i.e., the temperature at which magnetocrystalline anisotropy vanishes, is found to be approximately 120 K, which is 10 K lower than the bulk value. The Verwey transition is close to 110 K, again about 10 K lower than the bulk crystal value. Below the Verwey transition temperature, the uniaxial anisotropy of the monoclinic phase increases gradually and asymptotically approaches a constant value indicating a smooth structural transition rather than a sudden change. Resonance linewidth and effective damping increase abruptly below 110 K. The effective damping constant is determined to be ~0.01 and is independent of temperature from 300 K to 120 K.

Severe acute respiratory illness caused by 2019 novel coronavirus (2019-nCoV), officially named severe acute respiratory syndrome coronavirus (SARS-CoV-2) in late December 2019 is an extremely communicable disease. World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) as a pandemic as it has spread to at least 200 countries in a short span of time. Being a new disease there is lack of information about pathogenesis and proliferation pathways of this new coronavirus. Currently there is no effective treatment for coronavirus infection; major effort is to develop vaccine against the virus and development of therapeutic drugs for the disease. The development of genome-based vaccine and therapeutic antibodies require thorough testing for safety and will be available after some time. In the meanwhile, the available practical approach is to repurpose existing therapeutic agents, with proven safety record as a rapid response measure for the current pandemic. Here we discuss the presently used repurposed drugs for COVID-19 and the potential for ivermectin (IVM) to be used as a therapeutic option in COVID-19.

ICOVID-19 has involved serious occupational health risk to the health care professionals who are frequently exposed to infected individuals. Knowledge and attitude among health care professionals can prevent the spread of COVID-19. The present study was aimed to identify the current status of knowledge and attitude regarding COVID-19 among healthcare professionals in a tertiary care hospital. A questionnaire-based cross-sectional study was conducted among medical staff (doctors, nurses and lab technicians) in a tertiary care hospital to assess the knowledge and attitude toward COVID-19 among healthcare workers. The questionnaire comprised of three sections (demographic, knowledge and attitude) for data collections. Non parametric tests and Pearson correlation was used to analyze data using R (The comprehensive R archive network) version 3.6.2. Of the 117 respondents, 46.15% were doctors, 25.64% nurses and 28.20% technical staff. On data analysis, 94% were in good knowledge category, 6% had poor knowledge and 100% had positive attitude. In the knowledge section, median value for doctors was higher than nurses and technical staff (P = 0.02). Doctors showed higher median values for attitude than nurses and technical staffs (P = 0.02). A weak positive correlation, r(115)= .20, p=.0299 was evidenced between knowledge and attitude for COVID-19. Present study shows that the health care workers of a tertiary care institute had good knowledge and positive attitude towards COVID -19, though in some areas the knowledge and attitude was observed low. The study also observes that there is need for continuous teaching and training programs.

Efficient spin injection from epitaxial ferrimagnetic ${\mathrm{Ni}\mathrm{Fe}}_{2}{\mathrm{O}}_{4}$ thin films into a $\mathrm{Pd}$ layer is demonstrated via spin Seebeck effect measurements in the longitudinal geometry. The ${\mathrm{Ni}\mathrm{Fe}}_{2}{\mathrm{O}}_{4}$ films (60 nm to 1 $\ensuremath{\mu}$) are grown by pulsed-laser deposition on isostructural spinel ${\mathrm{Mg}\mathrm{Al}}_{2}{\mathrm{O}}_{4}$, ${\mathrm{Mg}\mathrm{Ga}}_{2}{\mathrm{O}}_{4}$, and ${\mathrm{Co}\mathrm{Ga}}_{2}{\mathrm{O}}_{4}$ substrates with lattice mismatch varying between 3.2 and 0.2%. For the thinner films ($\ensuremath{\le}330$ nm), an increase in the spin Seebeck voltage is observed with decreasing lattice mismatch, which correlates well with a decrease in the Gilbert damping parameter as determined from ferromagnetic resonance measurements. High-resolution transmission electron microscopy studies indicate substantial decrease of antiphase boundary and interface defects that cause strain relaxation, i.e., misfit dislocations, in the films with decreasing lattice mismatch. This highlights the importance of reducing structural defects in spinel ferrites for efficient spin injection. It is further shown that angle-dependent spin Seebeck effect measurements provide a qualitative method to probe for in-plane magnetic anisotropies present in the films.

The chalcogenide spinel CdCr2S4 is a well-established ferromagnetic semiconductor that exhibits unique properties and is a promising candidate for spintronic applications. With band gap in the visible wavelength region, CdCr2S4 nanocrystals offer the exciting possibility of tailoring both the optical and magnetic properties with precise morphology control. However, the synthesis of monodisperse CdCr2S4 nanocrystals is challenging and has not been reported. A unique “seed-mediated” growth process has been developed for the synthesis that involves using cubic-phase CdS, which has a face-centered cubic crystal structure similar to that of CdCr2S4, as a “seed” to react with CrCl3·6H2O in a solution mixture of 1-dodecanethiol and 1-octadecene. Remarkably, hexagonal-phase CdS is ineffective as a “seed” for formation of the desired product. A mechanism for formation of monodisperse CdCr2S4 nanocrystals by the selective growth process is proposed, and the structural and magnetic properties of the synthesized nano...

We experimentally investigate the propagation of Airy surface plasmon polaritons (Airy SPPs) on a gold film by multiphoton Photoemission Electron Microscopy (PEEM) at different excitation wavelengths and compare the result with rigorous numerical simulations. The typical bent trajectories of the excited two-dimensional beams are observed and analyzed over a wide range of wavelengths. We furthermore investigate the generation bandwidth of the diffraction grating from modal overlap calculations and evaluate the possibility of creating ultrashort Airy plasmon pulses. This provides a viable route to engineer two-dimensional ultrashort non-diffracting pulsed beams in the field of ultrafast nanophotonics.

Anisotropic-shaped CuCr2Se4 nanocrystals have been synthesized by thermal decomposition and reaction of novel mixed metal–oleate complexes with selenium in a high-boiling point organic solvent, trioctylamine (TOA). The synthesized CuCr2Se4 nanocrystals exhibit close to triangular and hexagonal morphology, with an average size of 20 nm. X-ray diffraction patterns and XPS spectral analysis confirm the formation of the pure spinel phase without any impurities. A possible reaction mechanism is suggested and formation pathways for the triangular and hexagonal shaped CuCr2Se4 nanocrystals are proposed. Magnetic studies indicate that the anisotropic-shaped CuCr2Se4 nanocrystals are superparamagnetic near room temperature but exhibit ferromagnetic behavior at lower temperatures, with magnetization values of 31 and 43 emu g−1 at 300 and 5 K, respectively.

We report a detailed study of the structural and ferromagnetic resonance properties of spinel nickel ferrite (NFO) films, grown on (100)-oriented cubic MgAl 2 O 4 substrates by direct liquid injection chemical vapor deposition (DLI-CVD) technique. Three different compositions of NFO films (Ni x Fe 3− x O 4 where x =1, 0.8, 0.6) deposited at optimized growth temperature of 600 °C are characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Vibrating Sample Magnetometry (VSM), and broadband ferromagnetic resonance (FMR) techniques. XRD confirms the growth of epitaxial, single crystalline Ni x Fe 3− x O 4 films. The out-of-plane lattice constant ( c ) obtained for Ni 0.8 Fe 2.2 O 4 film is slightly higher than the bulk value (0.833 nm), indicating only partial strain relaxation whereas for the other two compositions ( x =1 and x =0.6) films exhibit complete relaxation. The in-plane and out-of-plane FMR linewidths measurements at 10 GHz give the lowest values of 458 Oe and 98 Oe, respectively, for Ni 0.8 Fe 2.2 O 4 film as compared to the other two compositions. A comprehensive frequency (5–40 GHz) and temperature (10–300 K) dependent FMR study of the Ni 0.8 Fe 2.2 O 4 sample for both in-lane and out-of-plane configurations reveals two magnon scattering (TMS) as the dominant in-plane relaxation mechanism. It is observed that the TMS contribution to the FMR linewidth scales with the saturation magnetization M s . In-plane angle-dependent FMR measurements performed on the same sample show that the ferromagnetic resonance field ( H res ) and the FMR linewidth (Δ H ) have a four-fold symmetry that is consistent with the crystal symmetry of the spinel. SEM measurements show formation of pyramid-like microstructures at the surface of the Ni 0.8 Fe 2.2 O 4 sample, which can explain the observed four-fold symmetry of the FMR linewidth.

Background: Chronic obstructive pulmonary disease (COPD) is a leading respiratory illness affecting the quality of lives around the world. The present study aims to compare the efficacy and safety of combination of inhaled corticosteroid (ICS) and long acting β2 agonist (LABA) with long acting β2 agonist and long acting muscarinic antagonist (LAMA) in treatment of mild to moderate COPD in a tertiary care hospital.Methods: Total 132 patients with COPD were recruited on the basis of inclusion and exclusion criteria for 8 weeks study from outpatient clinic. A complete pulmonary examination including spirometry examination was done to rule out severe and very severe forms of COPD. Spirometry was performed at the time of recruitment for evaluation of forced expiratory volume in one second (FEV1) and measurement of SpO2 at the time of recruitment at 2 weeks and 8 weeks. Appropriate statistical methods were used to compare the qualitative and quantitative primary and secondary efficacy end points, p value

We have developed a vectorial type of measurement for the spin Seebeck effect (SSE) in epitaxial NiFe$_2$O$_4$ thin films which have been grown by pulsed laser deposition on MgGa$_2$O$_4$ (MGO) with (001) and (011) orientation as well as CoGa$_2$O$_4$ (011) (CGO), thus varying the lattice mismatch and crystal orientation. We confirm that a large lattice mismatch leads to strain anisotropy in addition to the magnetocrystalline anisotropy in the thin films using vibrating sample magnetometry and ferromagnetic resonance measurements. Moreover, we show that the existence of a magnetic strain anisotropy in NiFe$_2$O$_4$ thin films significantly impacts the shape and magnitude of the magnetic-field-dependent SSE voltage loops. We further demonstrate that bidirectional field-dependent SSE voltage curves can be utilized to reveal the complete magnetization reversal process, which establishes a vectorial magnetometry technique based on a spin caloric effect., 5 pages, 4 figures

Background: Prescribing generic medicine is still a debatable issue among prescribers and the issues of bioequivalence, quality, and safety remain problem areas. The perception that generic medicines are inferior to brand medicine can be eradicated by educating medical students who are the future prescribers. Aim and Objective: The correct knowledge of generic medicine among students will enhance the prescribing of low cost and effective medicines. Therefore, this study was conducted to analyze the knowledge and perception of generic medicines among undergraduates (UG), interns, and postgraduate (PG) students in a medical teaching institute. Materials and Methods: A questionnaire-based cross-sectional study was conducted among 230 medical students (145 UG, 50 interns, and 35 PG) in Uttar Pradesh University of Medical Sciences, Saifai, to assess knowledge and attitude of students for generic medicines. Chi-square test was used to analyze results. Results: About 98% of UG and interns and 100% of PG students were aware of generic medicines. Awareness of Jan Aushadhi Scheme is substantially poor in UG students as compared to interns and PG (P < 0.001). About 86% of student considered generic medicine of low cost, less effective (30%), poor quality (34%), and having more side effects (38%) as compared to branded medicine. Students believe product bonuses (28%) and advertisement (38%) by pharmaceuticals will alter their prescribing patterns in the future. About 71% of students (P < 0.001) consider that it is easier to remember a generic name and 89% of students (P < 0.001) wish to have further information regarding generic medicine in their medical curriculum. Conclusion: Medical students lack comprehensive knowledge and carry erroneous impressions for generic medicine. There is a need for more emphasis regarding generic medicine in UG medical curriculum. This will augment rational prescribing and cost-effective use of generic medicine in the future.

The magnetic and transport properties of magnetite (Fe3O4) films grown on isostructural substrates (MgAl2O4, MgGa2O4, and CoGa2O4), with varying degrees of lattice mismatches (3.8%, −1.4%, and −0.8%, respectively), have been investigated. A significant reduction in the density of antiphase boundary defects is observed for the Fe3O4 films grown under optimal process conditions on smaller lattice mismatch substrates (MgGa2O4 and CoGa2O4) as compared to MgAl2O4. Correspondingly, films on these substrates show much improved magnetic properties and sharper transition in the resistance values at the Verwey transition. Room temperature magnetic hysteresis and ferromagnetic resonance measurement studies indicate the presence of uniaxial magnetic anisotropy induced by substrate-induced strain in the film. Temperature-dependent transport measurements confirm that film thickness has a larger effect on the sharpness of the Verwey transition temperature than the degree of lattice mismatch with substrates.

We utilized spin Hall magnetoresistance (SMR) measurements to experimentally investigate pure spin current transport in thin film heterostructures of nickel ferrite (NiFe2O4,NFO) and normal metals (NM) Ta and Pt. We grew (001)-oriented NFO thin films by pulsed laser deposition on lattice-matched magnesium gallate (MgGa2O4) substrates, thereby significantly improving their magnetic and structural properties. We performed SMR measurements at room temperature in patterned Hall bar structures for charge currents applied in the [100]- and [110]-directions of NFO. We found that the extracted SMR magnitude for NFO/Pt heterostructures depends crucially on the Pt resistivity of the investigated Hall bar structure. We further study this resistivity scaling of the SMR effect at different temperatures for NFO/Pt. Our results suggest that the spin mixing conductance of the NFO/Pt interface and the Pt resistivity depend on the interface quality and thus a correlation between these two quantities exists.

We experimentally investigate the propagation of Airy surface plasmon polariton on a metallic film by using Multiphoton Photoemission Electron Microscopy and demonstrate a good agreement with large scale finite difference time domain simulations.

We investigate the switching characteristics in BaTiO3-based ferroelectric tunnel junctions patterned in a capacitive geometry with circular Ru top electrode with diameters ranging from similar to 430 to 2300 nm. Two different patterning schemes, viz., lift-off and ion-milling, have been employed to examine the variations in the ferroelectric polarization, switching, and tunnel electro-resistance resulting from differences in the pattering processes. The values of polarization switching field are measured and compared for junctions of different diameter in the samples fabricated using both patterning schemes. We do not find any specific dependence of polarization switching bias on the size of junctions in both sample stacks. The junctions in the ion-milled sample show up to three orders of resistance change by polarization switching and the polarization retention is found to improve with increasing junction diameter. However, similar switching is absent in the lift-off sample, highlighting the effect of patterning scheme on the polarization retention. (C) 2015 AIP Publishing LLC.

Spinel ferrite NiFe2 O4 thin films have been grown on three isostructural substrates, MgAl2 O4 , MgGa2 O4 , and CoGa2 O4 using pulsed laser deposition. These substrates have lattice mismatches of 3.1%, 0.8%, and 0.2%, respectively, with NiFe2 O4 . As expected, the films grown on MgAl2 O4 substrate show the presence of the antiphase boundary defects. However, no antiphase boundaries (APBs) are observed for films grown on near-lattice-matched substrates MgGa2 O4 and CoGa2 O4 . This demonstrates that by using isostructural and lattice-matched substrates, the formation of APBs can be avoided in NiFe2 O4 thin films. Consequently, static and dynamic magnetic properties comparable with the bulk can be realized. Initial results indicate similar improvements in film quality and magnetic properties due to the elimination of APBs in other members of the spinel ferrite family, such as Fe3 O4 and CoFe2 O4 , which have similar crystallographic structure and lattice constants as NiFe2 O4 .

Biomimetic materials possessing hierarchical surface roughness thrive when complementary terminal chemical functionality is introduced. However, incorporating terminal functionality on the biomimetic material is the challenge, especially, when its roughness needs to be preserved. Hence, we report surface chemical modification of biomimetic materials through water-based layer-by-layer deposition. The amine terminated biomimetic replica PDMS-replica(Silica/NH2) was prepared by treating silica-modified replica (i.e., PDMS-replica(Silica)) with the aqueous solution of branched ethoxylated polyethylenimine (EPEI). Next, -CF3 terminal PDMS-replica(Silica/NH2/CF3) was obtained by treating PDMS-replica(Silica/NH2) with the aqueous solution of phosphate ester fluorosurfactant. PDMS-replica(Silica/NH2/CF3) showed superhydrophobicity (advancing θwater ≈ 140°) and high oil repellency (advancing θoil ≈ 110°). X-ray photoelectron spectroscopy (XPS) revealed well-organized terminal -CF3 groups present on the PDMS-replica(Silica/NH2/CF3) surface. During the process of layer-by-layer deposition, the surface topography was monitored using scanning electron microscopy (SEM). This method could be extended to get desired terminal chemical functionality on the biomimetic materials which would furnish interesting surface properties in air or under water.