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Succinate dehydrogenase (SDH), Ca(2+) ATPase, Lactate dehydrogenase (LDH), are involved in energy metabolism. These enzymes can be used as indicators of the energy capacity of aerobic cells. The study investigated the effects of L-carnitine supplementation on M. pectoralis superficialis, M. pectoralis profundus, M. extensor carpi radialis muscle and M. flexor carpi ulnaris. Twenty-eight racing pigeons hatched at the same time were divided randomly into three groups. Eight pigeons, which were used as the control group, were sacrificed at 92-day old. The remaining twenty pigeons continued training until they reached 157-day old, with half the pigeons getting 25 mg/head/day of L-carnitine, while the other half given the same amount of water. The pigeons were assessed by histochemical methods and reverse transcription polymerase chain reaction (RT-PCR). To assess influence of L-carnitine on muscle fibre composition and the performance of three genes' mRNA, this study applied SDH localization, SDH, Ca(2+) ATPase and LDH mRNA expression to examine the results after oral administration of L-carnitine in vivo in racing pigeons. The results showed that L-carnitine significantly elevated the amount of white muscle fibre type IIa (p < 0.05). The mRNA expression quantities of SDH and LDH gene was higher via RT-PCR method. However, the expression of Ca(2+) ATPase remains similar. In conclusion, appropriate oral administration of L-carnitine of 25 mg/pigeon/day will result in an improvement of muscles related to flying.

The sulfur oxidative capability of Thiobacillus thiooxidans (T.t.) has been investigated with respect to bioleaching capability for cadmium-contaminated soil. A preliminary mechanism was deduced in this study. The sulfur is simultaneously oxidized to thiosulfate and sulfite by action of T.t. The thiosulfate exibits growth inhibitory effect and consequently the pathway from sulfur to thiosulfate is considered to be strictly energy-production-associated while the pathway from sulfur to sulfite was found both energy-producing and growth-associated. Kinetic study analysis showed that the biomass production follows the Monod kinetic model with inhibition, whereas the sulfate production follows the same Monod model without inhibition.

20003 Background: EBV DNA is detectable in the plasma in most patients (Pts) with lymphoepithelial carcinoma (LECA) and in some Pts with squamous cell carcinoma (SCC) of the HN. We investigated the prognostic significance of plasma EBV DNA level in a prospective phase II trial of concurrent cisplatin and CBRT for locally advanced HN carcinomas. Methods: Eligibility criteria included newly-diagnosed SCC or LECA of non-nasopharyngeal HN sites; stage III or IV disease; ECOG performance status ≤ 1; and age ≤ 70 years. Plasma EBV DNA levels were measured by real-time quantitative polymerase chain reaction (PCR) before treatment and at 6 weeks post-treatment. Pre-treatment gross tumor volume (GTV) was measured on CT, and invasion of bone and cartilage was assessed on CT and MRI. Cisplatin 40–50 mg/m2 was given on days 1, 8, 15 and 22 of CBRT. Radiotherapy consisted of 54 Gy/30 fractions/6 weeks and a concomitant boost (18 Gy/12 fractions) in the last 12 treatment days. The primary endpoint was overall survival (OS) and the secondary endpoint was progression-free survival (PFS). Survival curves were compared by the log-rank test and multivariate analysis was performed with Cox regression. Results: Between March 2001 and January 2005, 46 Pts were recruited (36 with SCC and 10 with LECA). Thirty-four Pts had stage III and 12 had stage IV disease. Pre-treatment plasma EBV DNA level was > 0 copy/ml in all Pts with LECA (range, 37 - 211737 copies/ml) and in 8 Pts with SCC (range, 10 - 48734 copies/ml). Ten Pts had plasma EBV DNA level > 0 copy/ml at 6 weeks post-treatment. With a median follow-up of 1.6 years, the 1-year OS rate was 87.7 % and 1-year PFS rate was 68.3%. On multivariate analysis, plasma EBV DNA > 0 copy/ml at 6 weeks post-treatment was the only independent predictive factor of decreased OS [hazard ratio (HR) 3.59, p = 0.04] for the entire group. In the subgroup of Pts with SCC, pre-treatment EBV DNA > 0 copy/ml was the only independent predictive factor of decreased locoregional PFS (HR 7.08, p = 0.03). Conclusions: Plasma EBV DNA level is a prognostic factor in Pts with locally advanced HN SCC and LECA. Further studies are warranted to confirm the finding and to elucidate its biological basis. No significant financial relationships to disclose.

We propose that the energy cost to remove one atom from the surface during ion bombard-ment is larger than the surface binding energy or bulk heat of sublimation. It is this value of the energy cost that is appropriate for use in analytic models of the sputtering process.

The total secondary electron emission (SEE) yield from the entrance and exit surfaces of thin carbon foils under fast ion (^(16)O, ^(19)F, ^(35)Cl) bombardment has been measured as a function of the ion energy and the ion beam current intensity. Using a retarding field, the energy distribution of secondary electrons integrated over almost all angles of emission in the backward and forward directions has also been measured. It is found that total forward emission is larger than backward emission by factors of up to 2.5, 2.7 and 3.4 for ^(16)O^(+3), ^(19)F^(+3) and ^(35)Cl^(+5), respectively. It is suggested that the enhancement of forward SEE may be partly due to effects from the instantaneous charge state of the heavy ion beam in the solid in addition to the binary collisions of the projectile with individual electrons in the target. It is also shown that the total SEE yield from the entrance and exit surfaces of the target foils decreases with ion beam current intensity; this may be a beam-induced temperature effect. The total SEE yield in both the forward and backward directions is less sensitive to surface conditions for high velocity ions than for low velocity ions and the total yield from both surfaces of the foils is proportional to the ion stopping power in the target, where the constant of proportionality depends on the properties of material.

The sputtering of Cu atoms from liquid targets by normally incident 5 keV Ar^+ ions was simulated using the multiple interaction molecular dynamics technique. Yields, energy distributions, and angular distributions of sputtered atoms were obtained at several temperatures slightly above and below the experimental melting point of copper. In all cases the resulting angular distributions of ejected atoms peaked more sharply than the cos θ behavior predicted by linear cascade theory. The ratio of yields from individual layers of the liquid targets, and the energy and angular distributions of ejected atoms generally were found to be similar to those obtained in previous simulations with solid Cu targets. Our results also are in qualitative agreement with Dumke's measurements of angular distributions and layer yield ratios of sputtered atoms from liquid Ga-In eutectic alloy targets. In particular, no marked changes in yields or energy distributions were observed when the temperature of the target was lowered below the nominal melting point of copper. The angular distributions were found to broaden with increasing temperature.

Techniques of generating liquid targets for molecular dynamics studies of sputtering were investigated in systems consisting of 603 Cu atoms. The effects of different boundary conditions on sputtering yield, layer yield ratio, energy distribution, and polar angular distribution of ejected particles were found to be important. A box boundary condition and a semiperiodic boundary condition were considered. The box boundary conditions required the particles to experience pure reflection at the boundaries, while semiperodic boundary conditions demanded position and momentum periodicity in the two dimensions defined by the surface of the target. Sputtering from the target generated with a box boundary condition resulted in a 60% higher total yield, a slightly higher first layer yield ratio, a 60% lower surface binding energy, and a sharper polar angular distribution than from the target generated under a semiperodic boundary condition at the same temperature. Since the results obtained with the semiperiodic boundary conditions are in better agreement with experimental sputtering results, we have concluded that the semiperiodic boundary conditions produces a target that better represents the free surface of real liquid systems.

Many-body forces obtained by the embedded-atom method are incorporated into the description of low-energy collisions and surface ejection processes in molecular dynamics simulations of sputtering from metal targets. Bombardment of small, single-crystal Cu targets (400–500 atoms) in three different orientations ({100}, {110}, {111}) by 5-keV Ar + ions have been simulated. The results are compared to simulations using purely pairwise additive interactions. Significant differences in the spectra of ejected atoms are found.

In this paper, we show that many-body interactions are important for describing the energy- and angle-resolved distributions of neutral Rh atoms ejected from keV-ion-bombarded Rh{111}. We compare separate classical-dynamics simulations of the sputtering process assuming either a many-body potential or a pairwise additive potential. The many-body potential is constructed using the embedded-atom method to describe equilibrium properties of the crystal, parameters from the Moliere potential to describe close encounters between energized atoms, and parameters from a Rh(2) potential to aid the description of the desorption event. The most dramatic difference between the many-body potential and the pair potential is in the predicted kinetic energy distributions. The pair-potential kinetic energy distribution peaks at ~2 eV, whereas the many-body potential predicts a broader peak at ~4 eV, giving much better agreement with experiment. This difference between the model potentials is due to the predicted nature of the attractive interaction in the surface region through which all ejecting particles pass. Variations of the many-body potential parameters are examined in order to ascertain their effect on the predicted energy and singular distributions. A specific set of parameters has been found which leads to excellent agreement with recent experimental trajectory measurement of desorbed Rh atoms. Approved for public release; distribution is unlimited.

Many-body forces obtained by the Embedded-Atom Method (EAM) [41 are incorporated into the description of low energy collisions and surface ejection processes in molecular dynamics simulations of sputtering from metal targets. Bombardments of small, single crystal Cu targets (400–500 atoms) in three different orientations ({100}, {110}, {111}) by 5 keV Ar+ ions have been simulated. The results are compared to simulations using purely pair-wise additive interactions. Significant differences in the spectra of ejected atoms are found.

The sputtering of In and Ga atoms from a “liquid” target composedof gallium coveredby a surface monolayer of indium by incident 5 keV Ar+ ions was simulated using the multiple interaction molecular dynamics technique. Yields, energy distributions, and angular distributions of sputtered atoms were obtained at a temperature above the melting point for the eutectic alloy. Similar information was obtained for a pure gallium and a pure indium target. Our results for layer yield ratios and angular distributions are in good qualitative agreement with Dumke's experimental data for the Ar+, In-Ga system. Absolute yields, however, were found to be sensitive to the detailed nature of the two-body potentials used to describe the atom-atom interactions.