Decay history and magnetic moments at high spin in Dy152

Average magnetic moments as well as information on the time evolution of the continuum structure of Dy152 at high spin have been obtained using the transient hyperfine magnetic field acting on fast ions traversing a thin, magnetized gadolinium foil. Dy152 nuclei were populated by the Ge76(80Se,4n)152Dy fusion-evaporation reaction at E(80Se)=326.5 MeV. The target-ferromagnet arrangement corresponds to a time window of about 701200 keV, rays contributing to the collective E2 bump, exhibit a negligible precession, in accordance with the very short lifetimes of these states. The precession of the angular distribution of discrete yrast rays deexciting the nucleus from spin I35Latin small letter h with stroke down yields an average magnetic moment for states with 43Latin small letter h with strokeI31Latin small letter h with stroke. The resulting g=0.21(2) is considerably lower than the collective value Z/A0.43 and indicates an appreciable contribution from aligned neutrons to the lower-spin region populated within the above time frame. The results are discussed in the framework of model calculations of the -ray cascade

Observation of superdeformation in Hg191

The first observation of superdeformation in the mass region A190 is reported. A rotational band of twelve transitions with an average energy spacing of 37 keV, an average moment of inertia scrF(2) of 110 Latin small letter h with stroke2 MeV-1, and an average quadrupole moment of 183 e b has been observed in Hg191; this band persists at low rotational frequency. These results are in excellent agreement with a calculation that predicts an ellipsoidal axis ratio of 1.65:1 for the superdeformed shape in this nucleus

Nucleon alignment in 191Hg. A competing mechanism at moderate spins

Detailed spectroscopic studies of the discrete γ-rays feeding and deexciting a 41 2-, 4.6 MeV level in 191Hg are reported. The resulting decay scheme indicates single-particle nature for the states above the 41 2- level. At moderate spin, the corresponding particle alignment mode competes favorably with collective oblate rotation. It is suggested that this sequence is associated with a non-collective prolate shape (ε{lunate}=0.1-0.15, γ≅-120°)

Superdeformed band in Hg192

The observation of a superdeformed band in the nucleus Hg192 is reported. The band has sixteen transitions with an average energy spacing of 36 keV and an average dynamic moment of inertia scrI(2) of 112 Latin small letter h with stroke2 MeV-1. This band persists to rather low rotational frequency (Latin small letter h with stroke0.125 MeV) and is proposed to extend in spin from 10+ to 42+. No transitions linking the superdeformed states and the low deformation yrast levels were found and the decay out of the superdeformed band appears to be statistical. This is the second case of superdeformation in the 190 region

Selective population of states in fission fragments from the S32+24Mg reaction

The symmetric and near-symmetric mass fission yields from the S32+24Mg reaction have been studied in a particle-particle- coincidence measurement. Evidence is presented for a selective population of states in Si28 fragments arising from the symmetric fission of the Ni56 compound nucleus. A statistical-model calculation of the expected strength to specific mutual excitations of the fission fragments is presented and compared to the experimental results. This calculation is found to describe the structures observed at high excitation energy in the fission Q-value spectra quite well. Analysis of the -ray spectra indicates, however, that a specific set of states in Si28, corresponding to a highly deformed prolate band, is populated more strongly than expected based on a purely spin-weighted, statistical decay of the compound nucleus. It is suggested that the population pattern of states in the fission fragments may reflect nuclear structure effects at the point of scission

Excited superdeformed bands in 191Hg

Two weakly populated rotational bands have been observed in 191Hg with properties (energy spacings, moments of inertia and lifetimes) very similar to those of the previously reported superdeformed band. Based on cranked Woods-Saxon calculations, these structures are interpreted as the first excited bands in the superdeformed minimum of 191Hg. Comparisons between the data and the calculations highlight the role of specific orbitals at large deformations

Lifetime measurements in the superdeformed band of Hg192

Lifetimes were measured for transitions in the superdeformed band of Hg192 with the Doppler-shift attenuation method. The results yield an essentially constant quadrupole moment of 202 e b and indicate that the sidefeeding lifetimes are of the same order as the state lifetimes. The data are consistent with calculations using the cranked Woods-Saxon Strutinsky method with pairing

FGF-23 in bone biology

Recent studies have demonstrated that levels of fibroblast growth factor 23 (FGF-23), a key regulator of phosphorus and vitamin D metabolism, rise dramatically as renal function declines and may play a key initiating role in disordered mineral and bone metabolism in patients with chronic kidney disease (CKD). The physiologic importance of FGF-23 in mineral metabolism was first identified in human genetic and acquired rachitic diseases and further characterized in animal models. FGF-23 and its regulators, including phosphate regulating endopeptidase homolog, dentin matrix 1 (DMP1), and matrix extracellular phosphoglycoprotein, are made primarily in bone, specifically in osteocytes. Dysregulation of these proteins results in osteomalacia, implicating the osteocyte in the regulation of skeletal mineralization. Studies in pediatric patients with CKD, the majority of whom have altered skeletal mineralization in early stages of CKD, have demonstrated that skeletal expression of both FGF-23 and its regulator, DMP1, are increased in early stages of CKD and that expression of these proteins is associated with alterations in skeletal mineralization. Thus, dysregulation of osteocytic proteins occur very early in the course of CKD and appear to be central to altered bone and mineral metabolism in this patient population

Genetic diagnosis of X-linked dominant hypophosphatemic rickets in a cohort study: Tubular reabsorption of phosphate and 1,25(OH)2D serum levels are associated with PHEX mutation type

<p>Abstract</p> <p>Background</p> <p>Genetic Hypophosphatemic Rickets (HR) is a group of diseases characterized by renal phosphate wasting with inappropriately low or normal 1,25-dihydroxyvitamin D₃(1,25(OH)₂D) serum levels. The most common form of HR is X-linked dominant HR (XLHR) which is caused by inactivating mutations in the <it>PHEX </it>gene. The purpose of this study was to perform genetic diagnosis in a cohort of patients with clinical diagnosis of HR, to perform genotype-phenotype correlations of those patients and to compare our data with other HR cohort studies.</p> <p>Methods</p> <p>Forty three affected individuals from 36 non related families were analyzed. For the genetic analysis, the <it>PHEX </it>gene was sequenced in all of the patients and in 13 cases the study was complemented by mRNA sequencing and Multiple Ligation Probe Assay. For the genotype-phenotype correlation study, the clinical and biochemical phenotype of the patients was compared with the type of mutation, which was grouped into clearly deleterious or likely causative, using the Mann-Whitney and Fisher's exact test.</p> <p>Results</p> <p>Mutations in the <it>PHEX </it>gene were identified in all the patients thus confirming an XLHR. Thirty four different mutations were found distributed throughout the gene with higher density at the 3' end. The majority of the mutations were novel (69.4%), most of them resulted in a truncated PHEX protein (83.3%) and were family specific (88.9%). Tubular reabsorption of phosphate (TRP) and 1,25(OH)₂D serum levels were significantly lower in patients carrying clearly deleterious mutations than in patients carrying likely causative ones (61.39 ± 19.76 vs. 80.14 ± 8.80%, p = 0.028 and 40.93 ± 30.73 vs. 78.46 ± 36.27 pg/ml, p = 0.013).</p> <p>Conclusions</p> <p><it>PHEX </it>gene mutations were found in all the HR cases analyzed, which was in contrast with other cohort studies. Patients with clearly deleterious <it>PHEX </it>mutations had lower TRP and 1,25(OH)₂D levels suggesting that the <it>PHEX </it>type of mutation might predict the XLHR phenotype severity.</p