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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.

Ex situ transmission electron microscopy was used to study the evolution of (311) defects and dislocation loops in the end-of-range damage region in silicon.

An experiment was undertaken to evaluate the effectiveness of high dose, low energy Czochralski (001) silicon wafers implanted with arsenic to produce a continuous amorphous layer to a depth of about 120 nm. The arsenic concentration surpassed the solid solubility of arsenic in silicon, arsenic clustering or precipitation transpiring on the estimated range of the implant. It was discovered that point defects in the implants, usually caused by arsenic clustering and precipitation, did not affect the enhanced diffusion of arsenic beyond the end-of-range damage.

Research was conducted to examine the influence of the silicon/oxide interface on interstitials. A di-interstitial surface recombination mechanism is proposed to account for the time dependence of oxidation enhanced diffusion. Experimental results suggest that the enhancement is proportional to the square root of the oxide growth rate. The enhancement lasts as long as the oxide is growing and depends on the oxidation rate.

X-ray diffraction and transmission electron microscopy studies reveal that grain size may be improved and crystalline defects minimized through the rapid thermal anneals of SrS:Ce thin films. Results were verified through comparison with electron paramagnetic resonance studies indicating that anneals reduce crystal field environment variance. Results also suggest that association with of Vsr shift with Ce3+ sites will enhance electroluminescence wavelengths as activator site symmetry is reduced.

The perturbance in the silicon vacancy concentration caused by the presence of TiSi2 films was examined using antimony silicon doping superlattices as a vacancy detector. An order of 1.5 relative vacancy supersaturation was observed in deposited titanium thickness 4-312 nm, 800-850-degrees celsius, 15-600 min. Vacancy injection mechanisms during titanium silicidation involve volume contraction and stress compensation.

Experimental measurements of fault development and dopant diffusion with respect to implant temperature of Si implanted GaAs show that increase in implant temperature from minus 2 to 40 degrees Celsius reduces Si diffusion and enhances density and maximum depth of extrinsic dislocation loops. In the minus 51 to 40 degrees Celsius temperature range, transition of amorphous Si to crystalline Si occurs in the GaAs. A model to simulate the experimental results indicates the variations in sputter yields of amorphous and crystalline semiconductors.

The applicability of type II damage as detectors for the quantification of interstitial fluxes in ion-implanted silicon was investigated. The results showed that the concentration of interstitials bound by the type II dislocation loops increased as the B+ dose was increased. The net concentration of interstitials ranged from 7.0x10(super 13) to 1.8x10(super 14) per square centimeter. Completely formed loops were more efficient by more than 20%.

The effectiveness of point defect detectors created by Si and Ge implantation was investigated. The results showed that type II dislocation loops can be utilized as point defect detectors in view of their efficiency in measuring point defects induced by oxidation. Atom concentration bound by the loops decreased after Ge ion implantation. On the other hand, when Si ion implantation was used, the net interstitial flux trapped by the loops was linearly proportional to the total supersaturation.

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).