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The study result which shows that a Giant Magneto-Resistive (GMR) mixed sensor is able to work as a very sensitive receiver for nuclear quadrupolar resonance (NQR) and nuclear magnetic resonance (NMR) systems are presented.

Determining phase transitions has always been a great challenge in material science due to their important fundamental and technological aspects. Recently, iron-based perovskites (RFeO3), exhibiting phase transitions at high temperatures, have attracted much interest for their functional properties at room temperature, such as multiferroicity (BiFeO3) and ultrafast spin dynamics (TmFeO3). In this family of materials, Samarium orthoferrite (SmFeO3) is a weak ferromagnet, ordering at high temperatures and exhibiting an intrinsic spin reorientation transition above room temperature, which is 'hidden' in macroscopic magnetization measurements in polycrystalline samples. In the present article, we show that the related magnetic high temperature phase transitions can be studied through their dielectric functions by spectroscopic ellipsometry in situ and without any need for an applied external magnetic field. The presence of this intrinsic spin reorientation transition is demonstrated for textured SmFeO3 films and we have determined a critical exponent of β = 0.45 ± 0.01 for the magnetic phase transition, coherently from optical, magneto-optical, and structural investigations. [ABSTRACT FROM AUTHOR]

The microstructure of a thick film of YFeO3 grown on (100)-SrTiO3 has been investigated by transmission electron microscopy. The film is divided into two different growth regions with the bottom part characterized by strong contrast variations in the high resolution transmission electron microscopy images indicating the presence of high strain fields. The top part of the film between 50 nm and the film surface shows a preferential growth of (001) YFeO3 ∥ (001) SrTiO3 columns with relaxation into a strain free state. The mosaicity of the film and the grain boundaries determine the exchange coupling between columns and results in a strong perpendicular magnetic anisotropy. [ABSTRACT FROM AUTHOR]

Structural, electrical, and magnetic properties of epitaxial thin films of Fe1.5Ti0.5O3-δ grown by pulsed laser deposition on SrTiO3(001) have been studied. For all the investigated range of preparation conditions, the thin films are single phase. The films prepared using oxygen pressure PO2 above 3×10-7 Torr presents a R(3)c symmetry structure. A single phase with the R(3) symmetry is obtained for the substrate temperature Ts=730 °C and PO2=2.6×10-7 Torr. This sample showed a ferrimagnetic behavior with Curie temperature Tc above room temperature, with a high magnetic moment of 0.6 μB/formula at 300 K. The film containing the disordered R(3)c phase is weakly ferromagnetic, with a spin glass-like signature. Optical properties seem to be governed more by the oxygen vacancies induced during the growth, than by the atomic ordering of titanium. [ABSTRACT FROM AUTHOR]

Several studies are conducted to explain the different structural, optical and magnetic properties of the ferromagnetic semiconductor hematite-ilmenite [Fe.sub.2-x][Ti.sub.x][O.sub.3-[delta]] thin films grown by the pulsed laser deposition technique. The optical properties of the films are shown to be highly dependent on the oxygen vacancies induced during its growth.

Abstract: A systematic study of Fe3O4 epitaxial films grown on single-crystalline SrTiO3(100) substrates using pulsed laser deposition has been conducted in order to elaborate magnetite films with properties suitable for their integration into spintronics heterostructures. Structural, morphologic, magnetic and transport properties of the films as a function of the deposition conditions were extensively explored in situ and ex situ. The conditions for the growth of high quality magnetite thin films were determined. The critical temperatures and magnetization close to the bulk values, low roughness and high conductivity make these samples perfectly suitable for future use in the spintronics heterostructures. [Copyright &y& Elsevier]

Among a plethora of drug nanocarriers, biocompatible nanoscale metal-organic frameworks (nanoMOFs) with a large surface area and an amphiphilic internal microenvironment have emerged as promising drug delivery platforms, mainly for cancer therapy. However, their application in biomedicine still suffers from shortcomings such as a limited chemical and/or colloidal stability and/or toxicity. Here, we report the design of a hierarchically porous nano-object (denoted as USPIO@MIL) combining a benchmark nanoMOF (that is, MIL-100(Fe)) and ultra-small superparamagnetic iron oxide (USPIO) nanoparticles (that is, maghemite) that is synthesized through a one-pot, cost-effective and environmentally friendly protocol. The synergistic coupling of the physico-chemical and functional properties of both nanoparticles confers to these nano-objects valuable features such as high colloidal stability, high biodegradability, low toxicity, high drug loading capacity as well as stimuli-responsive drug release and superparamagnetic properties. This bimodal MIL-100(Fe)/maghemite nanocarrier once loaded with anti-tumoral and anti-inflammatory drugs (doxorubicin and methotrexate) shows high anti-inflammatory and anti-tumoral activities. In addition, the USPIO@MIL nano-object exhibits excellent relaxometric properties and its applicability as an efficient contrast agent for magnetic resonance imaging is herein demonstrated. This highlights the high potential of the maghemite@MOF composite integrating the functions of imaging and therapy as a theranostic anti-inflammatory formulation.

Ectoparasites pose numerous research, health, and management problems for researchers and institutions. Our facility management experience was complicated by recurrence of murine fur mite (Radfordia affinis) infestation after several rounds of single-mode fur mite treatment with dichlorvos in the cage bedding. Subsequently, we successfully eradicated the fur mites using a multidrug therapeutic protocol. Over an 8-wk treatment period, 2 applications of topical selamectin were administered in conjunction with amitraz- and fipronil-treated nestlets changed weekly. Mice tolerated the therapy well with no side effects noted, and to date there has been no recrudescence. To our knowledge, this report is the first to describe combined use of these specific therapeutic agents to control fur mite infestation in laboratory mice.