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Objectives: To measure uptake and disposal kinetics and absolute absorption of vitamin K, using two stable isotope-labelled forms of vitamin [K.sub.1]. Subjects: Ten subjects (nine women and one man) aged between 22 and 31 years, with a mean ([+ or -] standard deviation) body mass index of 22.5 [+ or -] 2.4 kg/[m.sup.2]. Subjects took capsules containing 3 [micro]g of methyl-[sup.13]C vitamin [K.sub.1], three times a day for six days to reach a steady state for plasma vitamin [K.sub.1]. isotopic enrichment. On day seven, subjects were given an intravenous dose of Konakion MM to measure disposal kinetics and at the same time, a capsule containing 4 [micro]g of ring-[D.sub.4] vitamin [K.sub.1] to measure absorption. Plasma vitamin [K.sub.1] concentration was measured by high-performance liquid chromatography and isotopic composition by gas chromatography mass spectrometry. Results: The disposal kinetics of the intravenous dose of vitamin [K.sub.1] were resolved into two exponentials with half-times of 0.22 ([+ or -] 0.14) and 2.66 ([+ or -] 1.69) h. Absorption of oral, deuterated vitamin [K.sub.1] was 13 ([+ or -] 9) %. Conclusions: Two-compartmental kinetic parameters observed in this study are similar to those obtained previously using radioactive tracers, but there may be additional slow-turnover body pools acting as stores of vitamin [K.sub.1]. The kinetic parameters determined from the intravenous dose allowed determination of the absolute absorption of vitamin [K.sub.1] from a bolus oral dose. doi:10.1038/sj.ejcn.1602859; published online 1 August 2007 Keywords: vitamin [K.sub.1]; phylloquinone; stable isotope; kinetics; absorption, Introduction Vitamin K is a fat-soluble vitamin required as a cofactor in the post-translational carboxylation of glutamic acid to [gamma]-carboxyglutamic acid in vitamin K-dependent (VKD) proteins. VKD proteins were originally [...]

The role of fluorine in regards to boron diffusion in germanium and silicon preamorphized silicon prior to activation annealing is characterized. Observations reveal that boron atoms can diffuse in germanium-amorphized silicon during recrystallization at elevated temperatures without the assistance of additional dopants.

A fundamental understanding of the effect of scaling amorphous layers on the thermal stability of active concentrations is required for the formation of ultrashallow junctions. A study on the influence of boron on the evolution of the end of range defects for samples containing shallow amorphous layers formed by low energy germanium implants is conducted.

Presents information on a study which examined the evolution of both {311} defects and dislocation loops in the end-of-range (EOR) damage region in silicon amorphized by ion implantation. Two evolutionary pathways for {311} defects; Preferential site for dislocation loop nucleation.

A two-dimensional solid-phase epitaxial regrowth (2D-SPER) model is described that has used level set methods as implemented in the Florida object oriented process simulator to propagate regrowth fronts with variable crystallographic orientation. The modeling of the local SPER velocity as being linearly dependent on the local regrowth interface curvature has provided a stable model for stimulating 2D regrowth and mask edge defect formation in Si.

The defect evolution upon annealing of low energy, amorphizing germanium implants into silicon is studied using plan-view transmission electron microscopy. It was concluded that there is a defect stability threshold for Ge(super +1) amorphizing germanium implants with energy less than 10 KeV.

Studies the perturbance in silicon vacancy concentration induced by the presence of TiSi2 films. Use of antimony in silicon doping as vacancy detector; Stress compensation mechanism; Volume contraction mechanism.

It is a study of single gas cluster impacts into a silicon surface. A crystallographic crater sidewall orientation and a four-fold symmetric ejection of silicon atoms to the surface is exhibited as imaged by a cross-sectional high-resolution transmission electron microscopy (HRTEM).