Terahertz thermometry: combining hyperspectral imaging and temperature mapping at terahertz frequencies

The accurate and non-invasive determination of multiple physical parameters, with well-defined spatial resolution, is crucial for applications in manufacturing, chemistry, medicine and biology. Specifically, the ability to simultaneously measure both temperature and spectral signatures is still experimentally unavailable. To this end, we propose a mapping technique for biological systems, which exploits a linear correlation between terahertz wave reflectivity and temperature, and allows to spatially and spectrally resolve thermal distributions. This method is applied to a model biological system in two relevant cases where in one example, nanoplasmonic-induced photothermal effects are imaged gaining new insights into collective heating phenomena. In the second example, we demonstrate a joint thermal-hyperspectral imaging approach to chemically map the presence of a model drug formulation and simultaneously investigate its thermal stability in our biological system. This concept can be easily extended and widely applied to all materials that demonstrate a measurable change in their dielectric properties

Intérêt des échanges plasmatiques dans la pancréatite aiguë hypertriglycéridémique (une étude rétrospective)

LYON1-BU Santé (693882101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Theoretical study of Na(3p) excitation in Na-Ne collisions

Na(3p) excitation in Na-Ne collisions is analysed in terms of two independent mechanisms: (i) at low energy via two curve crossings leading to the simultaneous excitation of Ne atoms; (ii) at high energy by a direct transition. Diabatic potential energy curves and couplings are calculated using ab initio methods. The scattering equations are solved (quantally for mechanism (i) and by the impact-parameter method for mechanism (ii)). Total cross sections are calculated and agree reasonably well with the experimental results. In particular, the threshold behaviour is well reproduced by a seven-state model and at high energy the agreement between theory and experiment is improved with respect to previous work

Evaluation d'une chaine de detection automatique adaptee a un systeme de veille infrarouge bispectral

Après une description succincte du senseur infrarouge bispectral "VAMPIR" et de la chaîne d'acquisition numérique temps réel associée, on donne les principaux résultats d'une évaluation des algorithmes de détection, Une analyse statistique du signal représentatif de la cible recherchée et des fonds de rayonnement a permis de définir les caractéristiques du filtrage spatiotemporel adapté à la détection de la cible d'une part et à l'évaluation des fonds de rayonnement d'autre part. On peut ainsi générer une carte bispectrale des fonds remise à jour tour d'antenne après tour d'antenne, normaliser les signaux infrarouges dans les deux bandes passantes spectrales et assurer une prédetection à taux constant de fausses alarmes avec des paramètres optimisés en fonction du fond de rayonnement considéré. Les caractéristiques d'émissivité dans les deux bandes passantes spectrales permettent de réduire d'une manière très significative le taux final de fausses alarmes et de ne transmettre via un Préprocesseur de Signal (PPS) qu'un nombre limité de pistes au système d'Armes

Theoretical study of Na★ (3p) charge cloud orientation in Na + He collisions

The Projected Valence Bond potential energies of NaHe system calculated by Courbin-Gaussorgues and Sidis are used in an 8-state model to study the direct excitation, deexcitation probabilities and the orientation of the charge cloud of Na★ (3p). The corresponding calculation are carried out using the impact parameter method in the 0.5 Kev < ECM < 100 Kev energy range. A comparison with the theoretical prediction of a 3-state model of Andersen and Nielsen is made and discrepancies are discussed