FGF-23, a novel member of the FGF family, is the product of the gene mutated in autosomal dominant hypophosphatemic rickets (ADHR). FGF-23 has been proposed as a circulating factor causing renal phosphate wasting not only in ADHR (as a result of inadequate degradation), but also in tumor-induced osteomalacia (as a result of excess synthesis by tumor cells). Renal phosphate wasting occurs in approximately 50% of patients with McCune-Albright syndrome (MAS) and fibrous dysplasia of bone (FD), which result from postzygotic mutations of the GNAS1 gene. We found that FGF-23 is produced by normal and FD osteoprogenitors and bone-forming cells in vivo and in vitro. In situ hybridization analysis of FGF-23 mRNA expression identified “fibrous” cells, osteogenic cells, and cells associated with microvascular walls as specific cellular sources of FGF-23 in FD. Serum levels of FGF-23 were increased in FD/MAS patients compared with normal age-matched controls and significantly higher in FD/MAS patients with renal phosphate wasting compared with those without, and correlated with disease burden bone turnover markers commonly used to assess disease activity. Production of FGF-23 by FD tissue may play an important role in the renal phosphate–wasting syndrome associated with FD/MAS

Frequency and magnetic field dependent dielectric measurements have been performed on epitaxial thin films of the double perovskite La 2 NiMnO 6 , revealing a dielectric relaxation and magnetodielectric effect. The films are grown on Nb-doped and SrRuO 3-coated SrTiO 3 substrates using the pulsed laser deposition technique. While a rapid dielectric relaxation is observed at ϳ300 K, the relaxation rate increases dramatically at lower temperatures. Below the Curie temperature of La 2 NiMnO 6 , the dielectric constant increases in a magnetic field for a range of temperature. This temperature range depends on magnetic field and measurement frequency. The results are explained by the influence of a magnetic field on the dipolar relaxation.

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We report superconducting properties of tungsten meander structures fabricated using the focussed ion beam (FIB) induced technique. Three meander structures with individual line widths of ∼70, ∼300 and ∼450 nm were fabricated for evaluation and comparison of the superconducting properties. The resistance-temperature characteristics of the meanders were measured and analysed down to a temperature of 100 mK. The superconducting properties such as critical temperature (T C ) and upper-critical field (H C2 ) of these wires are in comparison to the reported values of FIB deposited tungsten available in literature. While the normal state resistance increases sharply as the width of the wire decreases, the superconducting transition temperature registered a slight decrease. Significant amount of residual resistance (3.8% of normal state value at 100 mK) was observed for the sample with the lowest width (70 nm). The residual resistance trails as function of temperature was analysed invoking theoretical models governing the phase slip induced dissipations in superconducting nanowires. The results indicated signature of phase slips as the width of the wire decreases: thermally activated phase slips dominant near to the T C and quantum phase slip (QPS) near to T C as well as much below to the T C . The magneto-resistance isotherms indicated quantum phase transitions (QPT); typical of a superconductor-to-insulator transition (SIT) driven by magnetic field. The SIT transition which originates from the intrinsic disorder present in the sample can be tuned by an external parameter such as magnetic field, and can be modelled by standard theories of QPT for quasi 2D or (2+1) D XY models. The successful fabrication of meander structures of W using FIB and the demonstration of superconductivity suggest that FIB deposited W can be exploited for many of the technological applications of superconducting nanowires such as superconducting nanowire single photon detectors, bolometers, transition edge sensors and even for quantum current standard employing the QPS phenomenon.

We report phase formation, and detailed study of magnetization and resistivity under magnetic field of MgB 2 polycrystalline bulk samples prepared by Fe-tube encapsulated and vacuum (10 -5 torr) annealed (750 0 C) route. Zero-field-cooled magnetic susceptibility (χ ZFC ) measurements exhibited sharp transition to superconducting state with a sizeable diamagnetic signal at 39 K (T c ). The measured magnetization loops of the samples, despite the presence of flux jumps, exhibited a stable current density (J c ) of around 2.4 x 10 5 A/cm 2 in up to 2 T (Tesla) field and at temperatures (T) up to 10 K. The upper critical field is estimated from resistivity measurements in various fields and shows a typical value of 8 T at 21 K. Further, χ FC measurements at an applied field of 0.1 T reveal paramagnetic Meissner effect (PME) that is briefly discussed.

We report synthesis of non-centrosymmetric BiPd single crystal by self flux method. The BiPd single crystal is crystallized in monoclinic structure with the P2 1 space group. Detailed SEM (Scanning Electron Microscopy) results show that the crystals are formed in slab like morphology with homogenous distribution of Bi and Pd. The magnetic susceptibility measurement confirmed that the BiPd compound is superconducting below 4K. Further, BiPd exhibits weak ferromagnetism near the superconducting transition temperature in isothermal magnetization (MH) measurements. The temperature dependent electrical resistivity also confirmed that the BiPd single crystal is superconducting at T c =4K. Magneto transport measurements showed that the estimated H c2 (0) value is around 7.0kOe. We also obtained a sharp peak in heat capacity Cp(T) measurements at below 4K due to superconducting ordering. The normalized specific-heat jump, C/γT c , is 1.52, suggesting the BiPd to be an intermediate BCS coupled superconductor. The pressure dependent electrical resistivity shows the T c decreases with increasing applied pressure and the obtained dT c /dP is -0.62K/Gpa.

We report electrical (angular magneto-resistance, and Hall), thermal (heat capacity) and spectroscopic (Raman, x-ray photo electron, angle resolved photo electron) characterization of bulk Bi 2 Se 3 topological insulator, which is being is grown by self flux method through solid state reaction from high temperature (950˚C) melt and slow cooling (2˚C/hour) of constituent elements. Bi 2 Se 3 exhibited metallic behaviour down to 5K. Magneto transport measurements revealed linear up to 400% and 30% MR at 5K under 14 Tesla field in perpendicular and parallel field direction respectively. We noticed that the magneto-resistance (MR) of Bi 2 Se 3 is very sensitive to the angle of applied field. MR is maximum when the field is normal to the sample surface, while it is minimum when the field is parallel. Hall coefficient (R H ) is seen nearly invariant with negative carrier sign down to 5K albeit having near periodic oscillations above 100K. Heat capacity (C p ) versus temperature plot is seen without any phase transitions down to 5K and is well fitted (Cp = γT + βT 3 ) at low temperature with calculated Debye temperature (Ѳ D ) value of 105.5K. Clear Raman peaks are seen at 72, 131 and 177 cm -1 corresponding to A 1g 1 , E g 2 and A 1g 2 respectively. Though, two distinct asymmetric characteristic peak shapes are seen for Bi 4f 7/2 and Bi 4f 5/2 , the Se 3d region is found to be broad displaying the overlapping of spin -orbit components of the same. Angle-resolved photoemission spectroscopy (ARPES) data of Bi 2 Se 3 revealed distinctly the bulk conduction bands (BCB), surface state (SS), Dirac point (DP) and bulk valence bands (BVB) and 3D bulk conduction signatures are clearly seen. Summarily, host of physical properties for as grown Bi 2 Se 3 crystal are reported here.

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