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Resonant inelastic x-ray scattering at the F 1s photoabsorption edge in LiF: Interplay of excitonic and conduction states, and Stokes' doubling

The excitation-decay processes at the F 1s photoabsorption edge in LiF crystal are studied using resonant inelastic x-ray scattering spectroscopy. The Raman-type linear dispersion and the narrowing of the x-ray fluorescence peak are observed at resonant excitation. A theoretical model based on the Kramers-Heisenberg formula describes well the main features in fluorescence spectra and allows one to

Platelet surface-bound IgG and platelet-specific IgG in plasma in childhood thrombocytopenia

Quantification of platelet-bound immunoglobulin is widely used in the evaluation of thrombocytopenia. Several methods have been devised among which labelled ligand-binding assays seem to be most appropriate. In series of adult patients such assays have been shown to be superior in separating immune-thrombocytopenia from thrombocytopenia of non-immune causes. We studied 62 children with thrombocyto

V2O3(0001) surface terminations: from oxygen- to vanadium-rich

Well-ordered epitaxial V2O3(0 0 0 1) films (thickness > 80 Angstrom) have been prepared on the clean Rh(1 1 1) surface and investigated with scanning tunnelling microscopy, low-energy electron diffraction, high-resolution electron energy loss spectroscopy and high-resolution X-ray photoelectron spectroscopy with synchrotron radiation. Atomically flat V2O3(0 0 0 1) surfaces, terminated by vanadyl (

Study of the reactivity and in vitro bioactivity of Sr-substituted alpha-TCP cements

In this study the effect of strontium substitution on the hydrolysis of alpha-tricalcium phosphate (alpha-TCP) toward the formation of calcium deficient hydroxyapatite (CDHA) was investigated. For that purpose substituted alpha-TCP powders with 1, 5 and 10 mol% Sr substitution for Ca were synthesized by reacting at 1500 degrees C stoichiometric amounts of CaCO3, SrCO3, and Ca2P2O7, followed by rap

Improved meal-related insulin processing contributes to the enhancement of B-Cell function by the DPP-4 inhibitor vildagliptin in patients with type 2 diabetes

The aim of this study was to evaluate the contribution of insulin processing to the improved meal-related B-cell function previously shown with the DPP-4 inhibitor vildagliptin. Fifty-five patients with type 2 diabetes (56.5 +/- 1.5 years; BMI=29.6 +/- 0.5kg/m(2); FPG = 9.9 +/- 0.2 mmol/l; HbA1c=7.7 +/- 0.1 %) were studied: 29 pateients were treated with vildagliptin and 26 patients with placebo,

Radiographic joint space in normal acromioclavicular joints

The acromioclavicular joint space in standard antero-posterior images of 151 normal subjects was measured. The joint space was significantly wider in men. There was a highly significant reduction of the joint space with age in both men and women and in persons past 60 a joint space of 0.5 mm or less is not pathological. A joint space wider than 7 mm in men and 6 mm in women is abnormal. The measur

Capacity of MIMO systems with antenna selection

We consider the capacity of multiple-input multiple-output systems with. reduced complexity. One link-end uses all available antennas, while the other chooses the L out of N antennas that maximize capacity. We derive an upper bound on the capacity that can be expressed as the sum of the logarithms of ordered chi-square-distributed variables. This bound is then evaluated analytically and compared t

Evolutionary and functional perspectives of the major histocompatibility complex class I antigen-processing machinery

Major histocompatibility complex (MHC) class I molecules present antigenic peptides to CD8+ T cells, providing the basis for immune recognition of pathogen-infected cells. Peptides generated mainly by proteasomes in the cytosol are transported into the lumen of the endoplasmic reticulum by transporters associated with antigen processing (TAP). The maturation of MHC class I molecules is controlled

The Role of Hox Transcription Factors in the Regulation of Hematopoiesis

Hematopoiesis is a lifelong, dynamic process, originating from a low number of hematopoietic stem cells (HSCs) residing in the adult bone marrow with the ability to self-renew and generate all blood lineages throughout life. Recent findings have demonstrated that the Homeobox (Hox) transcription factors are important regulators of both normal and malignant hematopoiesis, controlling proliferation,

Telomerase in yeast

The ribonucleoprotein enzyme telomerase synthesizes telomeric DNA by copying an internal RNA template sequence. The telomerase activities of the yeasts Saccharomyces castellii and Saccharomyces cerevisiae-with regular and irregular telomeric sequences, respectively-have now been identified and characterized. The S. cerevisiae activity required the telomerase RNA gene TLC1 but not the EST1 gene, bo

Calculation of the near field of aggregates of arbitrary spheres

We study a numerical method of calculating the near field of ensembles of arbitrary spheres by extending Mie theory. A recursive method based on the orders of scattering is presented. This method represents a concise way to calculate the near field of aggregates of any number of arbitrary spheres. Numerical examples are given to show its validity. (C) 2004 Optical Society of America.

Interieukin-6 promoter polymorphism is associated with bone quality assessed by calcaneus ultrasound and previous fractures in a cohort of 75-year-old women

Interleukin 6 (IL-6) is a multifunctional cytokine and a potent stimulator of bone resorption and has been implicated in the pathogenesis of osteoporosis in postmenopausal women. The aim of this study was to investigate if a functional JL-6 promoter polymorphism (-174) was related to bone mass and fractures in a cohort consisting of 964 postmenopausal Caucasian women aged 75 years. Bone mineral de