Search results for "sers"
showing 10 items of 478 documents
Stimulated Raman and Cars Spectroscopy of ν1 and 2ν2 (A1) Bands of 12CF4
1994
Two experimental coherent Raman techniques, stimulated Raman and coherent anti-Stokes Raman spectroscopy (CARS), were employed to study the Raman spectrum of CF 4 in the 900 cm −1 region. The stimulated Raman and CARS spectra of the ν 1 band of CF 4 were recorded at high resolution. The analysis of these spectra enabled some spectroscopic constants of this band to be refined and higher order constants to be determined for the first time. The first high-resolution CARS spectrum of the 2ν 2 (A 1 ) harmonic band is also presented. The rotational transitions of this band up to J = 40 were assigned and the first set of spectroscopic constants for this sub-level were determined. These results imp…
Techniques for measuring aerosol attenuation using the Central Laser Facility at the Pierre Auger Observatory
2013
The Pierre Auger Observatory in Malargue, Argentina, is designed to study the properties of ultra-high energy cosmic rays with energies above 10(18) eV. It is a hybrid facility that employs a Fluorescence Detector to perform nearly calorimetric measurements of Extensive Air Shower energies. To obtain reliable calorimetric information from the FD, the atmospheric conditions at the observatory need to be continuously monitored during data acquisition. In particular, light attenuation due to aerosols is an important atmospheric correction. The aerosol concentration is highly variable, so that the aerosol attenuation needs to be evaluated hourly. We use light from the Central Laser Facility, lo…
Excimer laser atherectomy in an uncrossable long chronic total occlusion through the subintimal space
2020
We present a successfully chronic total occlusions (CTO) coronary recanalisation with the subadventitial space by excimer laser atherectomy (ELCA) adjunctive therapy. Angiogram revealed non-significant diffuse disease of the left coronary system with a complex long proximal right coronary artery (RCA) CTO (J-CTO score 4) and collaterals (Rentrop Grade 2 and Werner classification CC1) from the septal branches (Figure 1, Panel A). CTO PCI of the RCA was then indicated and planned. Initially, antegrade approach and a retrograde approach technique were attempted without success. Thereafter, a rescue Antegrade Dissection Reentry strategy (ADR) was applied. A Pilot 200 (Abbott) was advanced in a …
Predicting mid-air gestural interaction with public displays based on audience behaviour
2020
Abstract Knowledge about the expected interaction duration and expected distance from which users will interact with public displays can be useful in many ways. For example, knowing upfront that a certain setup will lead to shorter interactions can nudge space owners to alter the setup. If a system can predict that incoming users will interact at a long distance for a short amount of time, it can accordingly show shorter versions of content (e.g., videos/advertisements) and employ at-a-distance interaction modalities (e.g., mid-air gestures). In this work, we propose a method to build models for predicting users’ interaction duration and distance in public display environments, focusing on …
In light of the ends. Copyright hysteresis and private copy exception after the British Academy of Songwriters, Composers and Authors (BASCA) and oth…
2015
In British Academy of Songwriters, Composers and Authors (BASCA) and others v Secretary of State for Business, Innovation and Skills, the High Court of Justice in matter of private copy exception provides the twofold prime opportunity to shed light on the state of the art of copyright in the UK and to flesh out the idea of 'legal hysteresis’. I support the reintroduction of the private copy exception, possibly in a less narrow fashion, and I explain the reasons why I am confident that my expectations will be fulfilled.
Towards the development of a fossil bone geochemical standard: An inter-laboratory study
2007
Ten international laboratories participated in an inter-laboratory comparison of a fossil bone composite with the objective of producing a matrix and structure-matched reference material for studies of the bio-mineralization of ancient fossil bone. We report the major and trace element compositions of the fossil bone composite, using in-situ method as well as various wet chemical digestion techniques. For major element concentrations, the intra-laboratory analytical precision (%RSDr) ranges from 7 to 18%, with higher percentages for Ti and K. The %RSDr are smaller than the inter-laboratory analytical precision (%RSDR; 100% was found for the high field strength elements (Hf, Th, Zr, Nb). The…
Ultrafast myoglobin structural dynamics observed with an X-ray free-electron laser.
2014
Light absorption can trigger biologically relevant protein conformational changes. The light-induced structural rearrangement at the level of a photoexcited chromophore is known to occur in the femtosecond timescale and is expected to propagate through the protein as a quake-like intramolecular motion. Here we report direct experimental evidence of such ‘proteinquake’ observed in myoglobin through femtosecond X-ray solution scattering measurements performed at the Linac Coherent Light Source X-ray free-electron laser. An ultrafast increase of myoglobin radius of gyration occurs within 1 picosecond and is followed by a delayed protein expansion. As the system approaches equilibrium it underg…
Biomolecules and nanostructured systems : characterization by Surface Enhanced Raman Scattering (SERS)
2014
This work addressed the study of several kinds of nanostructured systems, biomolecules and inorganic thin films, mainly by Surface Enhanced Raman Spectroscopy (SERS). The aim was to investigate the structure and the chemical bonds. Transmission electron microscopy (TEM) was also used to complete the structural characterization of the different samples.Firstly, the study was conducted on molecules of biological interest. The aim was to study the interaction between silver nanoparticles and proteins. With this aim, silver nanoparticles bioconjugated with different proteins (hemoglobin, cytochrome C, BSA and lysozim) were synthesized. SERS results allowed concluding that proteins are chemisorb…
Experimental demonstration of phase bistability in a broad-area optical oscillator with injected signal
2015
We demonstrate experimentally that a broad-area laserlike optical oscillator (a nondegenerate photorefractive oscillator) with structured injected signal displays two-phase patterns. The technique [de Valc\'arcel and Staliunas, Phys. Rev. Lett. 105, 054101 (2010)] consists in spatially modulating the injection, so that its phase alternates periodically between two opposite values, i.e., differing by $\ensuremath{\pi}$.
Laser Doppler flux and tissue oxygenation of experimental tumours upon local hyperthermia and/or hyperglycaemia
1992
Laser Doppler fluxmetry and oxygen partial pressure (pO2) histography have been applied to investigate the acute effects of hyperthermia (HT) and/or hyperglycaemia (HG) on microcirculatory function and tissue oxygenation of subcutaneous rat tumours growing on the dorsum of the hind foot. The experiments were performed to test whether, and to what extent, the two adjunct treatment modalities applied alone or in combination can modify these therapeutically relevant parameters. Local HT was performed in a saline bath (44 degrees C) for 2 h; HG was induced by i.v. infusion of 40% glucose solution for 2.5 h (blood glucose levels: 35-40 mM during heating). Laser Doppler flux (LDF) in superficial …