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Flash lamp annealing (FLA) is a modern annealing technique which, starting from microelectronics, has spread over new application areas like flexible electronics, photovoltaics or thin film deposition. Because of the short annealing time in the range of milliseconds and below, FLA allows the suppression of unwanted processes like diffusion, the annealing of temperature-sensible substrates, and the saving of process time and energy. In addition, it is predestined for roll-to-roll applications. However, the determination of the thermal cycle during FLA is challenging. The existing methods for a direct temperature measurement, mostly based on pyrometry, are elaborate and have to solve the problem to detect thermal radiation against the background of the intense flash light. An alternative way is simulation, but now an extended knowledge about the flash and the material system to be flashed is needed. In this work we describe a methodology to determine the thermal cycle during FLA without the need for a direct temperature measurement. This methodology is based on an optical-thermodynamic simulation and calibration experiments which can be implemented with reasonable effort under certain assumptions. The simulation considers not only the properties of the flash and the sample, but also the reflectivity of the chamber walls. Finally, the pros and cons of this methodology are shortly discussed.

Thermal processing in the millisecond range provides advanced, non-equilibrium annealing techniques which allow dedicated material modifications at the surface without affecting the substrate volume below. The process called flash lamp annealing (FLA) is one of the most diverse methods of short time annealing with applications ranging from the classical field of semiconductor doping to the treatment of layers on glass, polymers and other flexible substrates. It still continues to extend to other material classes and applications, and becomes of interest for an increasing number of users. Other phrases for FLA used throughout the literature are intense pulsed light sintering (IPL) or photonic curing. This review presents a short and comprehensive view of the current state of the art of FLA with a focus on functional coatings. After an introduction including historical aspects a look is taken to equipment issues as well as to the pioneering role which semiconductor processing in the framework of advanced chip technology played for the development of short time annealing. Mostly, examples of processing for photovoltaics, including doping aspects, hydrogen engineering, copper indium gallium diselenide (CIGS), silicon crystallization on glass, and transparent conductive oxides (TCO), including indium tin oxide (ITO), zinc oxide (also Al-doped AZO) as well as inkjet printing for flexible electronics will be presented.

The flexible and stretchable electronic market is increasing particularly in the field of biomedical electronics. Widely used printed silver conductive tracks today are only eligible for on-skin applications. However, for biomedical applications fully biocompatible, flexible and even stretchable materials for device fabrication are needed. This paper presents an additive printing approach to fabricate flexible and stretchable electronics by using a biocompatible platinum material. Usually, in order to realize electrically conducting Pt-interconnects by inkjet printing, it requires a furnace sintering at prohibitively high temperatures, which are not compatible with thermal sensitive polymeric substrates. This paper describes a high-power diode laser sintering (HPDL) and a flash lamp annealing (FLA) as promising alternative sintering methods. Both processes are eligible whereas laser sintering showed slightly better results. Bending tests and adhesive strength tests of platinum printed inks on polyimide with up to 180 000 cycles, show that printed platinum is a suitable biocompatible material for flexible electronics.

We present a study of the tunnel magneto-Seebeck (TMS) effect in MgO based magnetic tunnel junctions (MTJs). The electrodes consist of CoFeB with in-plane magnetic anisotropy. The temperature gradients which generate a voltage across the MTJs layer stack are created using laser heating. Using this method, the temperature can be controlled on the micrometer length scale: here, we investigate, how both, the TMS voltage and the TMS effect, depend on the size, position and intensity of the applied laser spot. For this study, a large variety of different temperature distributions was created across the junction. We recorded two-dimensional maps of voltages generated by heating in dependence of the laser spot position and the corresponding calculated TMS values. The voltages change in value and sign, from large positive values when heating the MTJ directly in the centre to small values when heating the junction on the edges and even small negative values when heating the sample away from the junction. Those zero crossings lead to very high calculated TMS ratios. Our systematic analysis shows, that the distribution of the temperature gradient is essential, to achieve high voltage signals and reasonable resulting TMS ratios. Furthermore, artefacts on the edges produce misleading results, but also open up further possibilities of more complex heating scenarios for spincaloritronics in spintronic devices., 12 pages, 6 figures

Three-dimensional topological insulators are fascinating materials with insulating bulk yet metallic surfaces that host highly mobile charge carriers with locked spin and momentum. Remarkably, surface currents with tunable direction and magnitude can be launched with tailored light beams. To better understand the underlying mechanisms, the current dynamics need to be resolved on the timescale of elementary scattering events (∼10 fs). Here, we excite and measure photocurrents in the model topological insulator Bi2Se3 with a time resolution of 20 fs by sampling the concomitantly emitted broadband terahertz (THz) electromagnetic field from 0.3 to 40 THz. Strikingly, the surface current response is dominated by an ultrafast charge transfer along the Se–Bi bonds. In contrast, photon-helicity-dependent photocurrents are found to be orders of magnitude smaller than expected from generation scenarios based on asymmetric depopulation of the Dirac cone. Our findings are of direct relevance for broadband optoelectronic devices based on topological-insulator surface currents., Surface currents in topological insulators can be controlled by light, but the underlying mechanisms are not well understood. Here, Braun et al. report an ultrafast shift photocurrent at the surface of Ca-doped Bi2Se3, whereas injection currents are much smaller than expected from asymmetric depopulation of the Dirac cone.

Avian rotaviruses are broadly distributed among birds, but only scarcely characterized on the molecular level. The VP4-, VP6-, VP7- and NSP5-encoding sequences of eight group A rotaviruses from chickens and turkeys determined here indicate a low degree of sequence similarity with mammalian rotaviruses. An NSP6-encoding region was missing in all chicken isolates except for isolate Ch2. Four novel genotypes (P[30], P[31], G22 and H8) were assigned by the Rotavirus Classification Working Group. Generally, chicken and turkey isolates clustered into separate branches of phylogenetic trees. However, chicken isolate Ch2 consistently clustered together with turkey isolates. Chicken isolate 06V0661G1 has a VP4-encoding sequence of unknown origin, but possesses VP6, VP7 and NSP5 genotypes typical for chicken isolates. These results might indicate interspecies transmission and reassortment among avian group A rotaviruses under field conditions. PCR protocols enabling amplification of avian and mammalian group A rotaviruses were developed for use in further epidemiological studies.

Shallow, Boron (B)-doped p+ emitters have been realized using spin-on deposition and Flash Lamp Annealing (FLA) to diffuse B into monocrystalline float zone Silicon (Si). The emitters extend between 50 and 140 nm in depth below the surface, have peak concentrations between 9x1019 cm-3 and 3x1020 cm-3, and exhibit sheet resistances between 70 and 3000 Ohm/Square. An exceptionally large increase in B diffusion occurs for FLA energy densities exceeding approximately 93 J/cm2 irrespective of 10 or 20 ms pulse duration. The effect is attributed to enhanced diffusion of B caused by Si interstitial injection following a thermally activated reaction between the spin-on diffusant film and the silicon wafer.

Patients in the emergency medical service (EMS) may have increased endogenous catecholamines because of pain or fear and may benefit from sedation similar to premedication in the hospital. During a simulated EMS scene call, 72 healthy male volunteers were either transported by paramedics from a third-floor apartment through a staircase with subsequent EMS transport with sirens (three stress groups of n = 12; total, n = 36) or asked to sit on a chair for 5 min and lie down on a stretcher for 15 min (three control groups of n = 12; total, n = 36). Catecholamine plasma samples were measured in the respective stress and control groups at baseline and after placebo IV (n = 12) or 25 (n = 12) or 50 (n = 12) microg/kg of midazolam IV throughout the experiment, respectively. Statistical analysis was performed with analysis of variance; P0.05 was considered significant. The Placebo Stress versus Control group, but not the 50 microg/kg Stress Midazolam group, had both significantly increased epinephrine (73 +/- 5 pg/mL versus 45 +/- 5 pg/mL; P0.001) and norepinephrine (398 +/- 34 pg/mL versus 278 +/- 23 pg/mL; P0.01) plasma levels after staircase transport. After EMS transport, the Placebo Stress versus Control group had significantly increased epinephrine (51 +/- 4 pg/mL versus 37 +/- 4 pg/mL; P0.05) but not norepinephrine (216 +/- 24 pg/mL versus 237 +/- 18 pg/mL) plasma levels, whereas no significant differences in catecholamine plasma levels occurred between groups after either 25 or 50 microg/kg of midazolam. In conclusion, simulated EMS patients may be subject to more stress during staircase transport than during transport in an EMS vehicle. Titrating sedation with 25 microg/kg of midazolam significantly reduced endogenous catecholamines but not heart rate.Simulated emergency medical service patients were more likely to be stressed when being transported by paramedics through a staircase than in an ambulance. Accordingly, it may be beneficial to inject sedative drugs before initiating transport to ensure patient comfort and safety.

1Department of Electronic Engineering, National Taipei University of Technology, Taipei 10608, Taiwan 2Department of Electrical and Computer Engineering, University of New Hampshire, Durham, NH 03824, USA 3Department of Electrical Engineering and Information Technology, Hochschule Darmstadt-University of Applied Sciences, Birkenweg 8, 64295 Darmstadt, Germany 4Department of Electrical Engineering, National Ilan University, Yilan 260, Taiwan 5Division for Biomedical & Industrial IC Technology, Industrial Technology Research Institute, Hsinchu 310, Taiwan

Solid sampling with laser vaporization has been coupled to an ICP emission spectrometer with an Echelle optical system and a solid-state-detector for the analysis of steel and soil samples. Pulsation of the vaporized material flow was compensated by real-time background correction and internal standardization, resulting in good accuracy and precision.

Introduction: Because of their minimal invasive access and low complication rate, thermoablative thechniques, increasingly used for the treatment of tumors in parenchymatous organs, are also interesting for patients bearing thyroid gland lesions necessitating surgery. Aim of this study was to evaluate and compare the dose-effect-relations of Laserinduced Thermotherapy (LITT) and Radiofrequencyinduced Thermotherapy (RFITT) in thyroid tissue to demonstrate the necessary parameters for a safe clinical use for the first time and to lay the foundations for a reasoned choice of procedure. Materials and methods: In porcine thyroid glands thermoablation was performed either by LITT or RFITT using power settings between 10 W and 20 W. Temperature spread during application was documented in 5 mm and 10 mm distance of the applicator. Postinterventional lesion diameters were measured and lesion sizes calculated. Results: Lesion volumes ranged between 0,4 ccm and 3 ccm and showed different characteristics in their spread for both techniques. A lesion volume plateau was observed in both techniques. Endtemperatures ranged between 75 °C and 117 °C in 5 mm distance and 52°C and 85°C in 10 mm distance of the applicator. Conclusion: Both techniques allow definitive and reproducible induction of clinical relevant lesions in thyroid tissue. Both methods differ in their respective complexity. Optimal energy doses and application times for a safe ablation in the clinical application of both techniques were documented for the first time.

This study is devoted to the performance of the CLIMET CI-8060, a white-light optical particle counter (OPC). Designed for clean-room monitoring, the off-the-shelf performance of this instrument is rather poor for outdoor studies. Modifications of this instrument are described turning this low-cost instrument into an OPC with excellent performance. The modifications include a reduction of the flow rate to 1.4 l/min, an altered design of the inlet nozzle, a buffer chamber to assure continuous flow, and a 16-channel pulse height analyzer. The modified version has been checked thouroughly. The counting efficiency is very close to 100% for particle sizes between 0.295 and 0.801 μm. The loss of giant particles is also marginal, as comparative tests with a cascade impactor show. The sizing calibration has been redetermined experimentally, using latex spheres, and theoretically, applying a software package by Jungert [1988] using the Mie theory. With the help of the established relationship between experimental and theoretical response for latex, calibration tables for any other particle material are obtained (in particular for ambient aerosols and H 2 O for fog and cloud condensation studies). The modified counter has been used for monitoring the growth of hygroscopic aerosols in humid conditions, using two different inlet lines, one of them drying the aerosol before entering the OPC, the other one preserving ambient conditions. This system allows to observe haze and fog formation and cloud condensation processes in situ at a one-minute time resolution.

In Escherichia coli as many as nine different genes coding for proteins with significant homology to peptidyl-prolyl cis/trans-isomerases (PPIases) have been found. However, for three of them, the histidine-rich SlyD, the homologous gene product of ORF149, and parvulin-like SurA, it was not known whether these proteins really possess PPIase activity. To gain access to the full set of PPIases in E. coli, SlyD, the N-terminal fragment of SlyD devoid of the histidine-rich region, as well as the protein product of ORF149 of E. coli named SlpA (SlyD-like protein) were cloned, overexpressed, and purified to apparent homogeneity. On the basis of the amino acid sequences, both proteins proved to be of the FK506-binding protein type of PPIases. Only when using trypsin instead of chymotrypsin as helper enzyme in the PPIase assay, the enzymatic activity of full-length SlyD and its N-terminal fragment can be measured. For Suc-Ala-Phe-Pro-Arg-4-nitroanilide as substrate,k cat/K m of 29,600m −1 s−1 for SlyD and 18,600m −1 s−1 for the N-terminal fragment were obtained. Surprisingly, the PPIase activity of SlyD is reversibly regulated by binding of three Ni2+ ions to the histidine-rich, C-terminal region. Because the PPIase activity of SlpA could be established as well, we now know eight distinct PPIases with proven enzyme activity in E. coli.

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This study explores the possibilities of using a Climet CI-8060 optical particle counter as a fog and cloud droplet counter in ambient conditions. Intercomparisons with an AERAS cascade impactor (modified for fog measurements) show that the performance of the instrument is excellent and yields accurate droplet size distributions in the range of 0.54 to 25 μm in one-minute time resolution. The CI-8060 was applied successfully in a field experiment investigating in-cloud scavenging of air pollutants. It is shown that the cloud droplet size distribution is a key parameter for the depletion of pollution by wet deposition. Being aware of the fact that commercial instruments built particularly for the purpose of cloud droplet sizing exist, the CI-8060 has some advantages: it is inexpensive, and it is rugged and easy to use in the field.

Field experiments with low-pressure cascade impactors (Type AERAS LPI 3010.06) have been carried out to determine whether coating of the impaction surfaces is necessary for the correct determination of aerosol mass size distributions in rural and suburban areas. In general, an impactor with coated surfaces collects up to 100% more giant particles ( d a > 1 μ m), and more than 20% more total mass, than an uncoated reference impactor. Also, the size distribution is in much better agreement with optical particle counter data, and the total mass is closer to values determined with a high-volume filter sampler, than in the case of the uncoated impactor.

Below-cloud scavenging coefficients for particles in the diameter range 0.28 < da < 15 μm could be determined as a function of the aerosol diameter da in a field experiment. The agreement with state-of-the-art theory is best for particles of about 2 μm diameter. Particles below this size seem to be much more efficiently removed than theory predicts - the experimental values are 10 to 100 times larger for aerosols of da≈0.5 μm. Giant particles of more than 2 μm diameter seem to be less efficiently scavenged than predicted. For 5 μm particles the experimental scavenging coefficients are about 2 to 5 times lower than the theoretical values. Reasons for these deviations are discussed in detail. The dependence on rainfall rate was found to be less pronounced than predicted by theory. The overall aerosol concentration decrease by below-cloud scavenging was found to be 6% (by number) or 21% (by volume), for a mean rainfall rate of 0.85 mm/hr and a mean duration of 170 minutes.