Ultrafast plasmonic photoemission in the single-cycle and few-cycle regimes.

Due to the highly increased interest in the development of state-of-the-art applications of photoemission in ultrafast electron microscopy, development of photocathodes and many more applications, a correct theoretical understanding of the underlying phenomena is needed. Within the framework of the single active electron approximation the most accurate results can be obtained by the direct solution of the time-dependent Schrödinger equation (TDSE). In this work, after a brief presentation of a numerically improved version of a mixed 1D-TDSE method, we investigated the characteristics of electron spectra obtained from the surface of metal nanoparticles irradiated with ultrashort laser pulses. During our investigation different decay lengths of the plasmonic-enhanced incident field in the vicinity of the metal were considered. Using the simulated spectra we managed to identify the behavior of the cutoff energy as a function of decay length in the strong-field, multiphoton and transition regimes.

Quantum Optical Signatures in a Strong Laser Pulse after Interaction with Semiconductors.

Electrodynamical processes induced in complex systems like semiconductors by strong electromagnetic fields have traditionally been described using semiclassical approaches. Although these approaches allowed the investigation of ultrafast dynamics in solids culminating in multipetahertz electronics, they do not provide any access to the quantum-optical nature of the interaction, as they treat the driving field classically and unaffected by the interaction. Here, using a full quantum-optical approach, we demonstrate that the subcycle electronic response in a strongly driven semiconductor crystal is imprinted in the quantum state of the driving field resulting in nonclassical light states carrying the information of the interaction. This vital step towards strong-field ultrafast quantum electrodynamics unravels information inaccessible by conventional approaches and leads to the development of a new class of nonclassical light sources.

Z oscillations in ion-induced fullerene fragmentation

Multiply charged ion-induced fragmentation and ionization of C60 is governed by electronic and nuclear stopping of the projectile as well as charge exchange. We have studied the collision dynamics as a function of the projectile atomic number Z ( 2

About streamlined brachial dialysis shunts.

The authors modified the technics of fistula forming. In such cases where to create a connection on the forearm is impossible one possible modality is to make it between major vessels on the arm. Streamlined connection was made in seven patients between basilic vein and brachial artery in three cases, between cephalic vein and brachial artery in four. There were two men and five women. The age interval was between 58 and 78 years. The longest observation period is 30 months. Until this time the fistulas were suitable for dialysis and had abundant yield. Because of the number of cases and the observation period has not yet make possible to come to final conclusion their goal was to present technical solution first of all. Their expectation is that with making them streamlined they will manage to create good perfusing and long lasting fistulas.

The effect of repeated doses of (-) deprenyl on the dynamics of monoaminergic transmission. Comparison with clorgyline.

The action of clorgyline and (-)deprenyl on the dynamics of dopaminergic and serotonergic transmission in the rat brain was compared. It was found, that daily administration of 0.25 mg/kg sc clorgyline, a specific MAO A inhibitor, reduced the turnover rate of both dopamine and serotonin after two weeks of injections. The treatment for two or four weeks with 0.25 mg/kg sc (-)deprenyl, a specific MAO B inhibitor, enhanced the turnover rate of dopamine and the fractional rate constant of dopamine efflux, reflecting an increased utilization rate of this amine in the striatum. Beside the augmentation of the dopamine turnover rate, the dopaminergic tone was also elevated by the reduction of the dopamine uptake in the striatum. Two week injections with the same dose of (-)deprenyl did not change the dynamics of serotonergic transmission.

An ultra rapid and sensitive high-performance liquid chromatographic method for determination of tissue and plasma free amino acids.

An ultra rapid and sensitive HPLC method for measuring individual free amino acids in biological fluids has been developed by using o-phthaldialdehyde/3-mercaptopropionic acid as derivatization agent and employing 3-micron-particle-size reversed-phase columns. Resolution of the amino acid derivatives is accomplished with an acetonitrile gradient in 12.5 mM sodium phosphate buffer, pH 7.2. These conditions facilitate separation of the 23 major tissue free physiological amino acids in the lower picomole range in less than 13 min. Muscle, liver, and kidney free amino acid concentrations, as determined by HPLC, are in the expected physiological range and compare favorably with those obtained by conventional amino acid analyzer.

Measurement of free amino acids in human biological fluids by high-performance liquid chromatography.

Favourable analytical conditions allowing amino acid analysis in biological fluids, acquired from small human biopsy specimens, were achieved by considering various derivatization methods, the mode of detection and the column used. By using o-phthalaldehyde-3-mercaptopropionic acid as derivatization agent (high sensitivity and stability) and fluorescence detection (excitation at 330 nm, emission at 450 nm), excellent separation of 26 amino acids was obtained in the lower pmol range (1-10 pmol). The reproducibility of the retention times was better than 1.0% for the majority of amino acids and the results from high-performance liquid chromatography (HPLC), compared favourably with those of conventional amino acid analysis (r = 0.97). HPLC technology facilitates amino acid analysis in biopsy specimens of less than 1 mg of tissue.

Increase of cloning efficiencies by using high-performance liquid chromatography-purified vectors and linkers.

High-performance liquid chromatography (HPLC) was applied to the purification of vector and linker DNAs used in molecular cloning experiments. The data clearly demonstrate that HPLC (Blue Column from LKB/TSK G 4000 SW) based on steric exclusion is a very rapid and convenient method for the size separation of DNA fragments that are virtually free of any contamination. Application of vector and linker DNAs, purified by this method, enabled us to clone nanogram amounts of avian myeloblastosis virus RNA, which was used for the evaluation of a recently described cloning procedure.