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Miniaturization of transistors, whose sizes reach a few tens of nanometers nowadays,implies new problems of heat control at very short scales. This big challenge among others enabled the emergence of nanoscale heat transfer as a new research domain. Near-field heat transfer is one of the axis of this thematic.It concerns the behavior of thermal waves at a scale shorter than their wave lengths.Under these conditions the waves with the highest energy density are evanescent, that is confined at the surface. Surface phonon-polariton (SPhP) is a particular case of an evanescent wave propagating at the surface of a polar dielectric material. This PhD work consists in examining SPhP propagation along the surface of micrometric glass tubes and in proving the ability of these waves to enhance heat transfer in these systems.A theoretical analysis has been carried out to justify the use of such heat waveguides whose thermal conductivity can be doubled due to SPhP. The experimental detection of those waves based on their diffraction at the tip of the glass tubes is then presented. This emission is measured thanks to the assembly of a microscope and a Fourier-transform IR spectrometer. The presence of SPhPs is proved through measured spectra exhibiting their characteristic spectral signature., La miniaturisation des transistors atteignant aujourd’hui des tailles de l’ordrede la dizaine de nanomètres a introduit des problèmes de contrôle de la chaleuraux courtes échelles. Ce défi industriel, parmi d’autres, a permis l’émergencede l’étude des transferts thermiques à l’échelle nanométrique. Un des axes derecherche de cette thématique concerne le rayonnement de champ proche. Ils’agit de comprendre le comportement des ondes thermiques sur des distancesinférieures à leur longueur d’onde. A cette échelle les ondes contenant la densitéénergétique la plus importante sont des ondes évanescentes, confinées ensurface. Le phonon-polariton de surface (PPS) en est un type : c’est une ondeévanescente se propageant à la surface de matériaux polaires et diélectriques.L’objectif de ce travail de thèse est d’examiner la propagation de PPS le longde la surface de tubes de verre micrométriques, et de montrer en quoi cettegéométrie favorise le transfert de chaleur par le biais de ces ondes.Une étude théorique a été menée pour justifier l’utilisation de ce guide d’ondesde chaleur dont la conductivité thermique peut être jusqu’à doublée grâce auxPPS. La présence des PPS est ensuite détectée expérimentalement. En effetla diffraction de ces ondes à la pointe du tube est décelée par un ensemblemicroscope-spectromètre à transformée de Fourier IR. Le spectre du rayonnementobtenu prouve la diffraction de PPS grâce à leurs signatures spectralesspécifiques.

U tekstu se donose rezultati istraživanja provedenih tijekom konzervator-sko-restauratorskih radova na dosad neobjavljenoj kopiji znamenite slike Paola Vero-nesea Otmica Europeiz Duždeve palače u Veneciji. Slika se danas čuva u Povijesnom i pomorskom muzeju Hrvatskog primorja u Rijeci, no muzejski inventari bilježe da potječe iz zbirke baruna Georga Hütterotta koja je bila smještena na otoku Sv. Andrije kod Rovinja. Multidisciplinarnost tima kemičara-analitičara, povjesničara umjetnosti i konzervatora-restauratora omogućila je pouzdanije odgovore na pitanja o tehnologiji i vremenu nastanke slike, odnosu kopije prema izvorniku i drugim kopijama iz 18. i 19. stoljeća te optimalan odabir restauratorskih postupaka i materijala., The paper brings forth results of a multidisciplinary research carried out in the course of conservation work on a copy of the painting by Paolo Veronese, The Rape of Europafrom the Doge’s Palace in Venice. The as yet unpublished copy is nowadays kept at the Maritime and History Museum of the Croatian Littoral in Rijeka. Mu-seum inventory books, however, reveal that it originated from the collection of Baron Georg Hütterottt, which used to be housed on the islet of St. Andrew, just off Rovinj. Laboratory investigations of the painting were carried out as part of the conservation procedure, aimed at exa-mining the chemical composition of the materials used, identifying the pigments and determining the sequence of paint coats in the painted layer of the original, as well as the relation of a subsequently added and painted piece of canvas to the rest of the composition. The information obtained was most valuable in establishing the time-frame from when the painting had originated to when its format was enlarged. We were able to identify: gypsum and traces of chalk in the preparation, lead white, barium white, Prussian blue and red ochre as well as dark earth pigments in the painted layers. A description is given of the laboratory, analytical methods: microanalysis of the chemical compounds using a scanning electron micros-cope, SEM/EDS and FT-IR micro-spectroscopy. By corre-lating the visual characteristics of the copy from Rijeka with the information on the pigments used, obtained by laboratory analyses, it was possible to date the paintingfrom the end of the 19th to the first decades of the 19th century, to the time when Veronese’s original was returned from Paris, reviving the public’s interest in this renowned piece of the Venetian cinquecentoart. The enlarging of the right-hand portion of the composition, albeit later in date and inferior in execution, followed soon after the painting had originated. The added portion was now folded and preserved, using a specially constructed stretcher frame, but only the original copy of the composition was presen-ted, matching the Veronese’s original. The multidisciplinary character of the team, made up of analytical chemists, art historians and conservators, pro-vided us with more reliable answers as to the technology and dating of the painting, the relation of the copy to the original and other 18th- and 19th-century copies, as well as the most favourable choice of conservation procedures and materials. The copy from Rijeka was put in the context of European artistic practice of repeating and citing notable paintings, and questions were raised as to the relation between the original, the copy and the facsimile, which is an ongoing issue to this day.

The possibility to fully exploit the diagnostic capabilities of SR-IRMS for studying single living cells under physiological conditions is limited by several constrains. First of all, the technology for manufacturing materials transparent to both IR and visible light is quite immature, limiting the design of fluidic devices to simple demountable liquid cells. In addition, the water spectral features become prominent in the Mid IR, hiding several cellular bands and therefore limiting the diagnostic capabilities of SR-IRMS. The overcoming of the so called "water absorption barrier" requires the improvement of the protocols for the compensation of buffer spectral contributions, a goal that can be achieved also advancing the quality of IR-suitable fluidic devices. In this paper, the technical solutions employed for microfabricating completely sealed IR-visible transparent fluidic devices for living cell analysis will be presented. Several examples of the results obtained in the study of living U937 monocytes subjected to different stimuli will be selected for highlighting both the advantages and the disadvantages offered by our approach for cellular biologyThe possibility to fully exploit the diagnostic capabilities of SR-IRMS for studying single living cells under physiological conditions is limited by several constrains. First of all, the technology for manufacturing materials transparent to both IR and visible light is quite immature, limiting the design of fluidic devices to simple demountable liquid cells. In addition, the water spectral features become prominent in the Mid IR, hiding several cellular bands and therefore limiting the diagnostic capabilities of SR-IRMS. The overcoming of the so called "water absorption barrier" requires the improvement of the protocols for the compensation of buffer spectral contributions, a goal that can be achieved also advancing the quality of IR-suitable fluidic devices. In this paper, the technical solutions employed for microfabricating completely sealed IR-visible transparent fluidic devices for living cell analysis will be presented. Several examples of the results obtained in the study of living U937 monocytes subjected to different stimuli will be selected for highlighting both the advantages and the disadvantages offered by our approach for cellular biology

International audience; Smalt is a potash glass with a blue colour given by cobalt, common as an artists' pigment between the 16th and 18th centuries. It often deteriorates, losing its colour and causing dramatic changes in the appearance of paintings. The changes in structure and elemental composition accompanying the loss of colour in the glass were examined in samples from paintings in the National Gallery, London and the Louvre using synchrotron micro Xray absorption spectroscopy, synchrotron reflectance FTIR microspectroscopy, Raman microspectroscopy and SEM-EDX. The leaching of potassium was found to be responsible for concurrent structural modifications in the glass: increase in polymerisation of the silicate network and change in cobalt coordination from tetrahedral towards octahedral, leading to colour change in the pigment. These results also form valuable reference data for examinations with lab-based techniques to distinguish between smalt that is degraded or a pale grey variety deliberately chosen by the artist. résumé Le smalt est un verre potassique dont la couleur bleue est due au cobalt, communément employé comme pigment par les artistes du xvi e siècle au xviii e siècle. Il se détériore souvent, en se décolorant et en entraînant des modifications radicales dans l'apparence des tableaux. Les changements de structure et de composition élémentaire qui accompagnent la décoloration du verre ont été examinés sur des échantillons provenant de tableaux du Louvre et de la National Gallery, à Londres, par microspectroscopie d'absorption X par

Aim Spectral Cytopathology (SCP) is a novel spectroscopic method for objective and unsupervised classification of individual exfoliated cells. The limitations of conventional cytopathology are well-recognized within the pathology community. In SCP, cellular differentiation is made by observing molecular changes in the nucleus and the cytoplasm, which may or may not produce morphological changes detectable by conventional cytopathology. This proof of concept study demonstrates SCP’s potential as an enhancing tool for cytopathologists by aiding in the accurate and reproducible diagnosis of cells in all states of disease. Method Infrared spectra are collected from cervical cells deposited onto reflectively coated glass slides. Each cell has a corresponding infrared spectrum that describes its unique biochemical composition. Spectral data are processed and analyzed by an unsupervised chemometric algorithm, Principal Component Analysis (PCA). Results In this blind study, cervical samples are classified by analyzing the spectra of morphologically normal looking squamous cells from normal samples and samples diagnosed by conventional cytopathology with low grade squamous intraepithelial lesions (LSIL). SCP discriminated cytopathological diagnoses amongst twelve different cervical samples with a high degree of specificity and sensitivity. SCP also correlated two samples with abnormal spectral changes: these samples had a normal cytopathological diagnosis but had a history of abnormal cervical cytology. The spectral changes observed in the morphologically normal looking cells are most likely due to an infection with human papillomavirus, HPV. HPV DNA testing was conducted on five additional samples, and SCP accurately differentiated these samples by their HPV status. Conclusions SCP tracks biochemical variations in cells that are consistent with the onset of disease. HPV has been implicated as the cause of these changes detected spectroscopically. SCP does not depend on identifying the sparse number of morphologically abnormal cells within a large sample in order to make an accurate classification, as does conventional cytopathology. These findings suggest that the detection of cellular biochemical variations by SCP can serve as a new enhancing screening method that can identify earlier stages of disease.

In this study we obtained Fourier transform infrared (FTIR) spectra of fixed prostate cell lines of differing types as well as the primary epithelial cells from benign prostatic hyperplasia (BPH). Results showed that by using multivariate chemometric analysis it was possible to discriminate and classify these cell lines, which gave rise to sensitivity and specificity values of >94% and >98%, respectively. Following on from these results the possible influences of different factors on the discrimination and classification of the prostate cell lines were examined. Firstly, the effect of using different growth media during cell culturing was investigated, with results indicating that this did not influence chemometric discrimination. Secondly, differences in the nucleus-to-cytoplasm (N/C) ratio were examined, and it was concluded that this factor was not the main reason for the discrimination and classification of the prostate cancer (CaP) cell lines. In conclusion, given the fact that neither growth media nor N/C ratio could totally explain the classification it is likely that actual biochemical differences between the cell lines is the major contributing factor. © 2009 Royal Society of Chemistry.

We have previously reported spectral differences for cells at different stages of the eukaryotic cell division cycle. These differences are due to the drastic biochemical and morphological changes that occur as a consequence of cell proliferation. We correlate these changes in FTIR absorption and Raman spectra of individual cells with their biochemical age (or phase in the cell cycle), determined by immunohistochemical staining to detect the appearance (and subsequent disappearance) of cell-cycle-specific cyclins, and/or the occurrence of DNA synthesis. Once spectra were correlated with their cells' staining patterns, we used methods of multivariate statistics to analyze the changes in cellular spectra as a function of cell cycle phase.

We report results from a study of human and canine mucosal cells, investigated by infrared micro-spectroscopy, and analyzed by methods of multivariate statistics. We demonstrate that the infrared spectra of individual cells are sensitive to the stage of maturation, and that a distinction between healthy and diseased cells will be possible. Since this report is written for an audience not familiar with infrared micro-spectroscopy, a short introduction into this field is presented along with a summary of principal component analysis.