Study of titanium(IV) speciation in sulphuric acid solutions by FT-Raman spectrometry

Issu de : ICSC30 2007 - 30th International Conference on Solution Chemistry, Perth, AUSTRALIA, 16-20 July 2007International audienceThe effects of the addition of titanium(IV) to aqueous solutions of sulphuric acid were studied by FT-Raman spectroscopy. Solutions containing 0 M to 4.01 M of titanium(IV) and 1.98 M to 6.17 M of sulphuric acid were analysed. A new peak, characteristic of titano-sulphate complexes, has been observed, in addition to the peaks characterising ions SO42− and HSO4−. Free HSO4− and SO42− concentrations have been determined from the Raman peak areas. From mass balance it was deduced that two complexes are present in the solution: [Ti(OH)2SO4] (aq) and [Ti(OH)2(SO4)2]2− (aq). Their apparent constants of formation have been estimated

Ultrafast Cardiac Imaging Using Deep Learning For Speckle-Tracking Echocardiography

High-quality ultrafast ultrasound imaging is based on coherent compounding from multiple transmissions of plane waves (PW) or diverging waves (DW). However, compounding results in reduced frame rate, as well as destructive interferences from high-velocity tissue motion if motion compensation (MoCo) is not considered. While many studies have recently shown the interest of deep learning for the reconstruction of high-quality static images from PW or DW, its ability to achieve such performance while maintaining the capability of tracking cardiac motion has yet to be assessed. In this paper, we addressed such issue by deploying a complex-weighted convolutional neural network (CNN) for image reconstruction and a state-of-the-art speckle tracking method. The evaluation of this approach was first performed by designing an adapted simulation framework, which provides specific reference data, i.e. high quality, motion artifact-free cardiac images. The obtained results showed that, while using only three DWs as input, the CNN-based approach yielded an image quality and a motion accuracy equivalent to those obtained by compounding 31 DWs free of motion artifacts. The performance was then further evaluated on non-simulated, experimental in vitro data, using a spinning disk phantom. This experiment demonstrated that our approach yielded high-quality image reconstruction and motion estimation, under a large range of velocities and outperforms a state-of-the-art MoCo-based approach at high velocities. Our method was finally assessed on in vivo datasets and showed consistent improvement in image quality and motion estimation compared to standard compounding. This demonstrates the feasibility and effectiveness of deep learning reconstruction for ultrafast speckle-tracking echocardiography

A multi-site campaign to measure solar-like oscillations in Procyon. II. Mode frequencies

We have analyzed data from a multi-site campaign to observe oscillations in the F5 star Procyon. The data consist of high-precision velocities that we obtained over more than three weeks with eleven telescopes. A new method for adjusting the data weights allows us to suppress the sidelobes in the power spectrum. Stacking the power spectrum in a so-called echelle diagram reveals two clear ridges that we identify with even and odd values of the angular degree (l=0 and 2, and l=1 and 3, respectively). We interpret a strong, narrow peak at 446 muHz that lies close to the l=1 ridge as a mode with mixed character. We show that the frequencies of the ridge centroids and their separations are useful diagnostics for asteroseismology. In particular, variations in the large separation appear to indicate a glitch in the sound-speed profile at an acoustic depth of about 1000 s. We list frequencies for 55 modes extracted from the data spanning 20 radial orders, a range comparable to the best solar data, which will provide valuable constraints for theoretical models. A preliminary comparison with published models shows that the offset between observed and calculated frequencies for the radial modes is very different for Procyon than for the Sun and other cool stars. We find the mean lifetime of the modes in Procyon to be 1.29 +0.55/-0.49 days, which is significantly shorter than the 2-4 days seen in the Sun.Comment: accepted for publication in Ap

Altimetry for the future: Building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the ‘‘Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

Altimetry for the future: building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the “Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

Les médias sociaux à l'heure des identités numériques : quels enjeux pour la recherche scientifique ?

Le lundi 4 mars 2013, l’équipe du séminaire « les Aspects Concrets de la Thèse » invitait les sociologues Antonio Casilli et Karim Hammou à venir discuter de la place qu’occupent actuellement les médias sociaux dans le métier de chercheur, des possibilités qu’ouvrent ces nouveaux outils mais aussi des pièges qu’ils peuvent receler. La séance donna lieu à un état des lieux des pratiques, à un partage d’expérience et à une réflexion théorique sur les enjeux des médias sociaux pour la recherche...

An anthropology of medico-legal expertise in North India

Alors que de nombreux travaux s’intéressent à l’expertise médico-légale à partir de son rôle dans la délibération judiciaire, peu d’études portent sur l’articulation de la médecine et du droit dans le quotidien des experts. Pourtant, déposer au tribunal ne constitue qu’un aspect parmi d’autres des activités des médecins légistes. Comprendre comment ceux-ci mettent en œuvre l’interface entre la médecine et le droit implique donc de s’éloigner du tribunal pour se pencher sur la pratique quotidienne de l’expertise à l’hôpital. Dans cette optique, la présente thèse s’intéresse à la médecine légale à partir d’une enquête ethnographique menée sur un an dans trois morgues hospitalières d’Inde du Nord, ainsi que sur un travail à partir d’archives judiciaires. Elle s’appuie sur des études de cas constituées à partir de l’analyse des interactions entre médecins et policiers ou membres des familles, des temps d’examen des corps et des stratégies de rédaction des rapports médico-légaux. Tout en resituant la médecine légale indienne dans son contexte historique, sociologique et institutionnel, ce travail, au croisement d’une anthropologie médicale et d’une anthropologie du droit, a pour but d’établir comment les médecins légistes comprennent les cas médico-légaux, rédigent leurs rapports et agissent sur le réel. Le diagnostic médico-légal et sa formulation écrite apparaissent comme des élaborations, construites au fil d’un processus hybride dont l’analyse permet de saisir les enjeux épistémologiques, politiques et sociaux de la pratique médico-légale.Whereas much has been written about the role played by medico-legal evidence in judicial deliberation, few studies focus on the articulation of medicine and law in the daily lives of experts. However, testifying in courts is but one aspect of forensic medicine. Understanding how medico-legal experts implement the interface between medicine and law therefore requires moving away from the court to focus on the daily practice of forensic expertise in the hospital. In this perspective, this thesis deals with forensic medicine based on a one-year ethnographic survey conducted in three hospital mortuaries in North India, as well as on judicial records. It relies on case studies formed out of the analysis of interactions between doctors and police officers or family members, medico-legal examinations and strategies for writing forensic reports. While placing Indian forensic medicine in its historical, sociological and institutional context, this work, at the intersection of medical and legal anthropology, aims to establish how medico-legal experts understand cases, write their reports and act on reality. The medico-legal diagnosis and its written formulation appear as elaborations, built through a hybrid process whose analysis makes it possible to grasp the epistemological, political and social issues surrounding medico-legal practice

« Retenir son stylo » pour l’équité. Le contournement des règles chez les médecins légistes en Inde

Dans les cas de décès non expliqués, les médecins légistes indiens interviennent dans la procédure policière et judiciaire indienne pour établir la cause de la mort. Cette détermination doit alors être effectuée d’un point de vue strictement médical et exclut toute participation du médecin à la délibération judiciaire. Pourtant, les médecins légistes disposent de ressources leur permettant de peser dans le cours judiciaire des cas en falsifiant les résultats des examens qu’ils conduisent. Cette contribution propose d’étudier comment les médecins peuvent décider de transgresser certaines règles pour secourir, sous certaines conditions, la famille d’un défunt. Elle montre que l’acte de contournement ne relève pas de l’arbitraire du médecin, mais qu’il répond à certains principes et normes en concurrence avec les règles officielles.In the event of an unexplained death, Indian medico-legal experts take part in the police and judicial proceedings with the purpose of establishing the cause of death. This determination must be made from a strictly medical point of view and excludes any involvement of the doctor in the judicial deliberation. However, medico-legal experts have the resources to influence the judicial course of cases by falsifying the results of the examinations they conduct. This contribution proposes to study how doctors can decide, under certain conditions, to break certain rules to rescue the family of a deceased person. It shows that circumventing the rules is not an arbitrary decision on the part of the doctor, but that it meets certain principles and standards that compete with official rules

MODELISATION DES MAREES OCEANIQUES A L'ECHELLE GLOBALE (ASSIMILATION DE DONNEES IN SITU ET ALTIMETRIQUES)

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Techniques et Natures

Image d’ouverture. Dans Divinity and Experience. The Religion of the Dinka, Godfrey Lienhardt publie une photo de jeunes garçons imitant des bovins dans une danse. La courbure des bras est présentée comme une attitude corporelle gracieuse et que les hommes adoptent pour leur propre plaisir lorsqu’ils sont seuls avec leur troupeau. 2003 [1961] NY : Oxford University Press Le biomimétisme désigne un ensemble de démarches et de processus de fabrication qui se proposent d’imiter la nature et les..