Scurvy in a patient with thalassaemia.

A 23-year-old man with a diagnosis of thalassaemia major on regular blood transfusions presented with complaints of intermittent gum bleeds, joint pain, palpable purpura and ecchymoses in both lower limbs, which was confirmed to be scurvy. He improved dramatically with vitamin C supplementation.

Strain modulated magnetocaloric effect in (111) oriented La0.7Sr0.3MnO3-SrRuO3 superlattices.

Magnetocaloric effect in (111)-oriented La0.7Sr0.3MnO3-SrRuO3 (LSMO-SRO) superlattices grown with both the stacking orders by reversing the individual layer thickness on (111)-oriented SrTiO3(STO) substrates using the pulsed laser deposition technique has been studied. Pseudomorphic growth with 0.64% in-plane tensile strain in [11 unit cell (u.c.)SRO/3u.c.LSMO]×15 superlattice is favourable for a larger change in entropy (ΔSM) as compared to relaxed growth with in-plane compressive strain in [11u.c.LSMO/3u.c.SRO]×15 superlattice. The reduction of ΔSM in [11u.c.LSMO/3u.c.SRO]×15 could be due to the orientation-dependent in-phase and out-of-phase tilt of the unit cell between ±1° along the 103pc of the {103}pc, which softens the exchange coupling and leads to the faster alignment of the magnetization near the Curie temperature (TC). Stabilization of the orthorhombic phase of LSMO in the superlattices with both stacking orders is evidenced from the existence of anomaly around the TC of LSMO and SRO in the temperature-dependent phonon frequency shifts. Reduction in symmetry of LSMO from the rhombohedral to orthorhombic structure modulates the Mn-O-Mn bond length and angles, which induces the spin reorientations and hence, modifies the electronic and magnetic properties in these LSMO-SRO superlattices. The ΔSM of these superlattices suggest that the strain, magnitude of the magnetic field, volume and magnetization of the ferromagnet can control the magnetocaloric effect. These results will be useful for designing the magnetic entropy based devices to improve renewable energy systems.

Effect of La0.7Sr0.3MnO3 crystal structures on magnetization of (1 1 1) oriented La0.7Sr0.3MnO3-SrRuO3 superlattices.

A series of superlattices consisting of 15 bilayers of ferromagnetic La0.7Sr0.3MnO3 (LSMO) and SrRuO3 (SRO) were grown with either stacking order on (1 1 1) oriented SrTiO3 (STO) substrates using the pulsed laser deposition technique. The Raman spectra of these superlattices show the existence of rhombohedral and orthorhombic crystal structures of LSMO in (111)STO/[11-unit cell (u.c.) LSMO/n-u.c. SRO]X15 superlattices with n = 2 and 3. Interestingly, the Raman spectra of (1 1 1)STO/[11-u.c. SRO/n-u.c. LSMO]X15 superlattices with n = 2 and 3 show only the orthorhombic structure of LSMO. The (1 1 1)STO/[11-u.c. LSMO/n-u.c. SRO]X15 superlattices exhibit enhanced magnetization with weak antiferromagnetic coupling whereas reduced magnetization with strong antiferromagnetic coupling is observed in (1 1 1)STO/[11-u.c. SRO/n-u.c. LSMO]X15 superlattices. The observed magnetic properties of these superlattices can be explained by the interfacial structural coupling, as evident from their Raman spectra which suggest a modification in the stereochemistry of Mn at the interfaces.

Laser induced structural phase transformation of cobalt oxides nanostructures.

Face-centered-cubic (fcc) and hexagonal-close-packed (hcp) phases of cobalt monoxide (CoO) nanostructures are prepared using thermolysis route at the same reaction temperature 296 degrees C with synthetic approach conditions. These nanostructures show mixture of nearly spherical and nanoflake morphologies. The structural phases of these nanostructures transform to spinel-Co3O4 by application of heat or Raman excitation laser beam power. The absorbance spectra of fcc and hcp-CoO and Co3O4 nanostructures yield significantly higher values of band gap which can be explained by electron confinement. Such results provide new opportunities for optimizing and enhancing the properties and performance of cobalt oxide nanomaterial.

Magnetocaloric effect and improved relative cooling power in (La(0.7)Sr(0.3)MnO(3)/SrRuO(3)) superlattices.

Magnetic properties of a series of (La(0.7)Sr(0.3)MnO(3)/SrRuO(3)) superlattices, where the SrRuO(3) layer thickness is varying, are examined. A room-temperature magnetocaloric effect is obtained owing to the finite size effect which reduces the T(C) of La(0.7)Sr(0.3)MnO(3) layers. While the working temperature ranges are enlarged, - ΔS(M)(max) values remain similar to the values in polycrystalline La(0.7)Sr(0.3)MnO(3). Consequently, the relative cooling powers are significantly improved, the microscopic mechanism of which is related to the effect of the interfaces at La(0.7)Sr(0.3)MnO(3)/SrRuO(3) and higher nanostructural disorder. This study indicates that artificial oxide superlattices/multilayers might provide an alternative pathway in searching for efficient room-temperature magnetic refrigerator for (nano) micro-scale systems.

Tunable magnetic interaction at the atomic scale in oxide heterostructures.

We report on a systematic study of a number of structurally identical but chemically distinct transition metal oxides in order to determine how the material-specific properties such as the composition and the strain affect the properties at the interface of heterostructures. Our study considers a series of structures containing two layers of ferromagnetic SrRuO3, with antiferromagnetic insulating manganites sandwiched in between. The results demonstrate how to control the strength and relative orientation of interfacial ferromagnetism in correlated electron materials by means of valence state variation and substrate-induced strain, respectively.

Acute anterior uveitis as the initial presentation of alkaptonuria.

Alkaptonuria is a rare autosomal recessive metabolic disorder that may present with multi-system involvement such as ochronotic arthropathy, renal, urethral and prostatic calculi, cardiac valvular lesions and pigmentation of the skin, sclera, cartilage and other connective tissues. An association of the disease with uveitis has never been reported. We report the first case of alkaptonuria with ochronotic arthropathy presenting with recurrent acute anterior uveitis as the initial manifestation. The possible common link with the HLA-B27 gene is discussed.

Magnetodielectric effect in Bi(2)NiMnO(6)-La(2)NiMnO(6) superlattices.

Multilayer superlattices consisting of multiferroic Bi(2)NiMnO(6) (BNMO) and La(2)NiMnO(6) (LNMO) have been grown heteroepitaxially on pure and Nb-doped SrTiO(3) substrates using the pulsed laser deposition technique. In a series of superlattice structures grown with a fixed BNMO layer thickness of ten unit cells, we find that the c-axis lattice parameter, Curie temperature and magnetocapacitance are strongly dependent upon the number of stacked LNMO unit cells in the repeating units. The thickness-dependent magnetodielectric effect is attributed to the fluctuations in electric and magnetic dipole ordering due to the substrate and interface induced stress in the superlattice structures. An enhanced magnetodielectric effect in multilayers with LNMO thicknesses larger than six unit cells is explained based on possible canting of spin at the interfaces of LNMO and BNMO.

Evaluation of formalin-acetone sedimentation in the concentration of stool for intestinal parasites.

Formalin-acetone sedimentation was compared with the formalin-ether method for the concentration of stool for intestinal parasites. Of 80 stool specimens, 45 (56.25%) were positive for parasites by the formalin-acetone method. The figures for the two methods were formalin-ether 35 (43.75%) and for the direct lacto-phenol cotton blue wet mount method 17 (21.25%). There was no statistically significant difference in the parasite recovery rate between the two methods. Acetone is more stable, safer, and a cheaper fat solvent and promises to be a useful alternative to ether.

Melioidosis--a report from Pondicherry, South India.

Melioidosis is an acute infectious disease caused by a safety-pin-shaped gram-negative bacteria called Burkholderia pseudomallei. Here, we report the first case of melioidosis in a middle aged male agricultural worker, from Pondicherry. The isolation of this organism from subcutaneous nodules on the extensor aspect of his limbs underlines the diversity of its clinical presentation. Difficulty in identifying the organism which mimics any other non-fementing gram-negative bacilli (NFGNB) on cursory examination, highlights the importance of identification of NFGNB in endemic areas for specific treatment and prevention.