81 research outputs found
Far-infrared magnetotransmission of YBa2(ZnxCu(1-x))3O(7-d)
Measurements of the far infrared magnetotransmission of
YBa2(ZnxCu(1-x))3O(7-d) thin film (x = 0.025) deposited on a wedged MgO
substrate are reported. The application of magnetic field perpendicular to the
ab plane produces at low temperature a linear increase of transmission for
frequencies below 30 cm-1. We present a model of high frequency vortex dynamics
which qualitatively explains these results.Comment: 2 pages with 2 figures, presented on LT2
Magnetism and Electronic Structure in ZnFeO and MnFeO
Density functional calculations are used to study magnetic and electronic
properties of the spinel ferrites, ZnFeO and MnFeO. Correct
magnetic orderings are obtained. ZnFeO is predicted to be a small gap
insulator in agreement with experiment. MnFeO is found to be a low
carrier density half-metal in the fully ordered state. However, strong effects
on the electronic structure are found upon partial interchange of Fe and Mn
atoms. This indicates that the insulating character may be due to Anderson
localization associated with the intersite Mn-Fe disorder.Comment: 3 pages, submitted to mmm01 conferenc
Faraday rotation spectra of bismuth-substituted ferrite garnet films with in-plane magnetization
Single crystalline films of bismuth-substituted ferrite garnets have been
synthesized by the liquid phase epitaxy method where GGG substrates are dipped
into the flux. The growth parameters are controlled to obtain films with
in-plane magnetization and virtually no domain activity, which makes them
excellently suited for magnetooptic imaging. The Faraday rotation spectra were
measured across the visible range of wavelengths. To interprete the spectra we
present a simple model based on the existence of two optical transitions of
diamagnetic character, one tetrahedral and one octahedral. We find excellent
agreement between the model and our experimental results for photon energies
between 1.77 and 2.53 eV, corresponding to wavelengths between 700 and 490 nm.
It is shown that the Faraday rotation changes significantly with the amount of
substituted gallium and bismuth. Furthermore, the experimental results suggest
that the magnetooptic response changes linearly with the bismuth substitution.Comment: 15 pages, 6 figures, published in Phys. Rev.
1,25(OH)2D3 Alters Growth Plate Maturation and Bone Architecture in Young Rats with Normal Renal Function
Whereas detrimental effects of vitamin D deficiency are known over century, the effects of vitamin D receptor activation by 1,25(OH)2D3, the principal hormonal form of vitamin D, on the growing bone and its growth plate are less clear. Currently, 1,25(OH)2D3 is used in pediatric patients with chronic kidney disease and mineral and bone disorder (CKD-MBD) and is strongly associated with growth retardation. Here, we investigate the effect of 1,25(OH)2D3 treatment on bone development in normal young rats, unrelated to renal insufficiency. Young rats received daily i.p. injections of 1 µg/kg 1,25(OH)2D3 for one week, or intermittent 3 µg/kg 1,25(OH)2D3 for one month. Histological analysis revealed narrower tibial growth plates, predominantly in the hypertrophic zone of 1,25(OH)2D3-treated animals in both experimental protocols. This phenotype was supported by narrower distribution of aggrecan, collagens II and X mRNA, shown by in situ hybridization. Concomitant with altered chondrocyte maturation, 1,25(OH)2D3 increased chondrocyte proliferation and apoptosis in terminal hypertrophic cells. In vitro treatment of the chondrocytic cell line ATDC5 with 1,25(OH)2D3 lowered differentiation and increased proliferation dose and time-dependently. Micro-CT analysis of femurs from 1-week 1,25(OH)2D3-treated group revealed reduced cortical thickness, elevated cortical porosity, and higher trabecular number and thickness. 1-month administration resulted in a similar cortical phenotype but without effect on trabecular bone. Evaluation of fluorochrome binding with confocal microscopy revealed inhibiting effects of 1,25(OH)2D3 on intracortical bone formation. This study shows negative effects of 1,25(OH)2D3 on growth plate and bone which may contribute to the exacerbation of MBD in the CKD pediatric patients
Civil Society, Nonprofit Organizations, and Citizenship in China: An Editorial Introduction to the China Issue
Growth And The Growth Hormone-Insulin Like Growth Factor 1 Axis In Children With Chronic Inflammation:Current Evidence, Gaps In Knowledge And Future Directions
Growth failure is frequently encountered in children with chronic inflammatory conditions like juvenile idiopathic arthritis, inflammatory bowel disease and cystic fibrosis. Delayed puberty and attenuated pubertal growth spurt is often seen during adolescence. The underlying inflammatory state mediated by pro-inflammatory cytokines, prolonged use of glucocorticoid and suboptimal nutrition contribute to growth failure and pubertal abnormalities. These factors can impair growth by their effects on the growth hormone-insulin like growth factor axis and also directly at the level of the growth plate via alterations in chondrogenesis and local growth factor signaling. Recent studies on the impact of cytokines and glucocorticoid on the growth plate studies further advanced our understanding of growth failure in chronic disease and provided a biological rationale of growth promotion. Targeting cytokines using biologic therapy may lead to improvement of growth in some of these children but approximately one third continue to grow slowly. There is increasing evidence that the use of relatively high dose recombinant human growth hormone may lead to partial catch up growth in chronic inflammatory conditions, although long term follow-up data is currently limited. In this review, we comprehensively review the growth abnormalities in children with juvenile idiopathic arthritis, inflammatory bowel disease and cystic fibrosis, systemic abnormalities of the growth hormone-insulin like growth factor axis and growth plate perturbations. We also systematically reviewed all the current published studies of recombinant human growth hormone in these conditions and discuss the role of recombinant human insulin like growth factor-1
The Evolution of Third Sector Research and the Journal Voluntas: The Editors’ Impressions
Contains fulltext :
232100.pdf (Publisher’s version ) (Closed access)2 p
Barriers for Third Sector Organizations and best practice coping strategies
International audienc
Perminvar-Like Behaviour in some Hexagonal Ferrites
A novel, perminvar-like behaviour of the magnetization curves in the hard direction of titanium containing bulk and thin film barium hexagonal ferrites was observed at low temperatures. The DC moments and AC susceptibilities in the 1-1000 Hz frequency range were measured by VSM and SQUID magnetometers in the easy and hard magnetic directions at temperatures from 5 to 300 K. The perminvar-like effects were explained on the basis of the reorientation of Fe2+ - Ti4+ pairs in octahedral 12k sites of the hexagonal lattice
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