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Particle simulations on a flat-topped somewhat underdense (typically n0/nc = 0.6) plasma slab by Nikolic [Phys. Rev. E 66, 036404 (2002)] were seen to give transient stimulated scattering behavior with frequency shift [omega0 - omegas(approximately omegap)] considerably less than the plasma frequency omegap. This has been linked to the electron acoustic wave (EAW) and the scattering was thus seen as another example of stimulated electron acoustic scattering inferred by Montgomery [Phys. Rev. Lett. 87, 155001 (2001)] from experiments on low-density plasmas. Montgomery had noted the difficulty of how one could have a very narrow observed scattering from a wave whose damping was at least initially very high. Our Vlasov-Maxwell simulations for such somewhat underdense (n0/nc > or = 0.25) plasmas show that the simulation resonance was in fact determined by the beating of the pump with a new "radiating pseudocavity" electromagnetic mode for the slab at a frequency close to omegap with relatively low loss. This allows the initial narrow-band excitation of the kinetic electrostatic electron nonlinear (KEEN) waves (the nonlinear "cousins" of EAWs) at a well-defined frequency (omegaK approximately omega0 - omegap < omegap) which is not necessarily the value given by the EAW dispersion relation. (The KEEN wave characteristics have been discussed by Afeyan [33rd AAAC (2003), #238, IFSA 2003].) The consideration of such a mechanism is relevant to moderately underdense hot plasmas.

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Quantitative analysis of aluminum and copper alloys by means of laser-induced plasma spectroscopy (LIPS) has been investigated for three representative laser pulse durations (80 fs, 2 ps, and 270 ps). The experiments were carried out in air at atmospheric pressure with a constant energy density of 20 J/cm2. Because the decay rate of the spectral emission depends on the laser pulse duration, the optimum detection requires an optimization of the temporal gating acquisition parameters. LIPS calibration (sensitivity and nonlinearity) and the limit of detection (LOD) are discussed in detail. While the LOD of minor elements embedded in alloy samples obtained by sub-picosecond or sub-nanosecond laser pulses are both time and element dependent, provided an appropriate temporal window is chosen, the optimum LODs (several parts per million (ppm)) prove to be independent of the laser pulse duration. Finally, it is found that for elements such as those detected here, gated LIPS spectra using picosecond or sub-picosecond laser pulses provide much better LOD values than non-gated spectra.

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Laser ablation of an aluminum target as a function of the pulse duration, for fluences up to 30 J/cm(2) and a wavelength of 0.8 microm, is investigated by means of a fluid code. For a given fluence, the ablation depth shows a minimum for a pulse duration of approximately 10 ps between a maximum obtained for pulses shorter than approximately 1 ps and a lower maximum obtained for pulses in the nanosecond range, in qualitative agreement with published experimental results. The decrease in ablation depth with increase in pulse duration observed between 1 and 10 ps results from the reduced temperature rise near the surface due to increased inward heat transport. The increase in the ablation depth above approximately 10 ps is due to the increase in electron density gradient length while the laser pulse intensity is close to maximum, which thus enables the plasma to absorb more of the laser pulse energy for increased ablation.

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Laser ablation due to an ultrashort laser pulse on a massive aluminum target was investigated by means of a one-dimensional fluid code. Clear separation between the ablated matter and the unablated target is seen to occur through spinodal decomposition involving thermodynamic instabilities near the critical point of aluminum. The code also shows that the end of the ablation process is preceded by the ejection of droplets, which form about 15% of the total ejected mass.

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In high-risk and complicated coronary intervention, the risk of acute closure is unpredictable. Thrombus and platelet deposition at the intervention site may also have further effects on subsequent restenosis. In vivo infusion of activated protein C has previously been shown to achieve potent anticoagulation without any haemostatic side effects. We now evaluated the in vitro and in vivo efficacy of polymer-coated coronary stents loaded with purified rabbit Activated Protein C (APC). By measuring 125I-fibrinogen/fibrin deposition APC-loaded stent-wires were antithrombotic compared to albumin-loaded, inhibited-APC-loaded, plain polymer-coated and stainless steel stent-wires. In a balloon injury rabbit iliac artery model, APC-loaded stents did not occlude (0/14) compared to plain stents (9/15) and BSA-loaded stents (2/4). Relative 111In-labelled platelet deposition showed a similarly significant degree of inhibition. In conclusion, APC-loading could render stents significantly less thrombotic. Whether an effective antithrombogenic stent like this effectively reduces restenosis rates warrants further evaluation.

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A novel interferometry technique is presented by which, in one shot, one can measure phase changes with a resolution of tens of femtoseconds while extending the measurement over picoseconds or even longer. The method is based on spectral (frequency-domain) interferometry with a pair of linearly chirped pules as probes. With this technique we obtained single-shot measurements of the rapid phase changes induced by optical field ionization of air. This allowed us to calculate the time profile of the electron density created by an intense short laser pulse.

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Anti-neutrophil cytoplasmic antibodies (ANCA) against native bactericidal/permeability-increasing protein (nBPI) have gained increasing diagnostic significance in inflammatory bowel disease and cystic fibrosis. However, routine detection of BPI-ANCA requires pure antigen in large quantities. As nBPI is difficult to isolate and is very susceptible to proteolytic cleavage with subsequent epitope loss, it was the aim of this study to determine whether recombinant BPI (rBPI) can be used as an alternative to nBPI as target antigen for ANCA in diagnostic procedures. Therefore, 93 BPI-ELISA-positive sera and controls were compared in different ELISAs using nBPI, rBPI, unglycosylated rBPI and a 21-kDa amino-terminal fragment of rBPI. ELISA results were confirmed by immunoblotting and all sera were tested in indirect immunofluorescence (IFT). There was an 88% (82/93) agreement in recognition of nBPI and rBPI by ANCA in both ELISA systems, yet the quantitation of BPI-ANCA in relative units showed a less optimal result and correlated only by 45% (p < 0.01). Most sera recognized nBPI, rBPI and unglycosylated rBPI equally suggesting that glycosylation has no influence on antigen recognition. Only two sera were positive for the 21-kDa nBPI indicating that the binding sites for ANCA are either conformational epitopes and/or are located mainly on the carboxy-terminal part of the BPI molecule. Most BPI-ELISA-positive sera were negative in IFT (43%), but a perinuclear (pANCA, 30%), a cytoplasmic (cANCA,10%) or an atypical ANCA (aANCA, 2%) staining pattern, as well as a cytoplasmic pattern only on formaldehyde-fixed granulocytes (13%) were also observed. Overall, no characteristic pattern was seen for BPI-ELISA-positive sera in IFT. Taken together, these data suggest that rBPI offers an excellent alternative to nBPI for broad-based BPI-ANCA ELISA and will be of great value in further investigations of BPI-ANCA interactions.

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A convenient method is described for optical characterization of thin films during growth. The method has been demonstrated on lead zirconate titanate (PZT) films deposited by pulsed laser ablation for various temperatures. The optical constants of the PZT films as well as the film growth rate were determined in situ by fitting (with three free parameters) the calculated reflectance as a function of film thickness to the experimental reflectance curve as a function of deposition time, as obtained by unpolarized laser reflectometry. The fitted parameters are the uniform complex PZT refractive index and the layer thickness (assumed proportional to time), with the complex refractive index of the platinum substrate being measured previously. These results compare well with the subsequent ellipsometric measurements made to assess the precision of the reflectometry technique.

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Proteinase 3 (PR3) is a multifunctional serine protease found in myeloperoxidase-positive granula of PMN. It is also the main target antigen for antineutrophil cytoplasmic antibodies (ANCA) found in Wegener's granulomatosis (WG). There is ample evidence that these autoantibodies play an active role in the pathogenesis of this disease. We have established the expression of the autoantigen (PR3) in a baculovirus expression system using insect cells. Recombinant PR3 was identified by IIF, direct ELISA using 3 different MoAbs and by catching ELISA using a MoAb and a rat polyclonal Ab or cANCA-positive WG patient sera. As purification of human PR3 from blood-derived PMNs has been shown to be difficult and very inefficient, insect cell-derived recombinant PR3 offers new possibilities for obtaining sufficient amounts of this protein to facilitate further biochemical characterizations.

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Little-exploited properties of silver halide films are used to record the spatial distribution of 10.6 microm-CO(2) laser pulses with a dynamic range of at least 20. The IR radiation is shown to sensitize commonly available silver halide films to subsequent visible radiation. A permanent, high-resolution image is thus formed of radiation too low in energy to eject directly photoelectrons. The method is calibrated for the film found most useful for this technique.