Automatic Optimal Input Command for Linearization of cMUT Output by a Temporal Target

2014 IEEE. Reprinted, with permission, from Sébastien Ménigot, Dominque Certon, Dominque Gross and Jean-Marc Girault, Automatic Optimal Input Command for Linearization of cMUT Output by a Temporal Target, 2014 IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control. This material is posted here with permission of the IEEE. Such permission of the IEEE does not in any way imply IEEE endorsement of any of the Université François Rabelais de Tours' products or services. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected] audienceCapacitive micromachined ultrasonic transducers (cMUTs) are a promising alternative to the piezoelectric transducer. However, their native nonlinear behavior is a limitation for their use in medical ultrasound applications. Several methods based on the pre-compensation of a preselected input voltage have been proposed to cancel out the harmonic components generated. Unfortunately, these existing pre-compensation methods have two major flaws. The first is that the pre-compensation procedure is not generally automatic, and the second is that they can only reduce the second harmonic component. This can, therefore, limit their use for some imaging methods, which require a broader bandwidth, e.g., to receive the third harmonic component. In this study, we generalized the presetting methods to reduce all nonlinearities in the cMUT output. Our automatic pre-compensation method can work whatever the excitation waveform. The precompensation method is based on the nonlinear modeling of harmonic components from a Volterra decomposition in which the parameters are evaluated by using a Nelder-Mead algorithm. To validate the feasibility of this approach, the method was applied to an element of a linear array with several types of excitation often encountered in encoded ultrasound imaging. The results showed that the nonlinear components were reduced by up to 21.2 dB

Micro-resonators based on integrated polymer technology for optical sensing

International audienceResearch on sensors has experienced a noticeable development over the last decades especially in label free optical biosensors. However, compact sensors without markers for rapid, reliable and inexpensive detection of various substances induces a significant research of new technological solutions. The context of this work is the development of a sensor based on easily integrated and inexpensive micro-resonator (MR) component in integrated optics, highly sensitive and selective mainly in the areas of health and food. In this work, we take advantage of our previous studies on filters based on micro-resonators (MR) to experiment a new couple of polymers in the objective to use MR as a sensing function. MRs have been fabricated by processing SU8 polymer as core and PMATRIFE polymer as cladding layer of the waveguide. The refractive index contrast reaches 0.16 @ 1550 nm. Sub-micronic ring waveguides gaps from 0.5 to 1 µm have been successfully achieved with UV (i-line) photolithography. This work confirms our forecasts, published earlier, about the resolution that can be achieved. First results show a good extinction coefficient of ~17 dB, a quality factor around 104 and a finesse of 12. These results are in concordance with the theoretical study and they allow us to validate our technology with this couple of polymers. Work is going on with others lower cladding materials that will be used to further increase refractive index contrast for sensing applications

Solar photo-Fenton and UV/H2O2 processes against the antidepressant Venlafaxine in urban wastewaters and human urine. Intermediates formation and biodegradability assessment

In this work, the use of Advanced Oxidation Processes (AOPs) against the degradation of an emerging contaminant has been subjected under systematic investigation. The optimization of treatment of the anti- depressant drug Venlafaxine (VFA) was performed, using UV light, the combined UV/H2O2 process, solar light, Fenton and finally the solar photo-Fenton process in laboratory scale. The degradation kinetics, the time necessary to remove 90% of the contaminant and the optimal reactants concentration were proposed. The treatment in pure water, (synthetic) wastewater and urine was assessed, in an effort to identify the opportunities and pitfalls the application of process would encounter in a field application. Treatment by the UV-based methods was found sufficiently efficient and the application of the solar photo-Fenton process showed feasibility in a potential field application with appropriate context. Real urban wastewater effluents after biological and physicochemical treatment were tested, as well as human urine, as a proposal for on-site collection and treatment was also treated. Biological treatment before applying the tested AOPs improved their efficiency, and the strategy of diluting urine prior to treatment greatly enhanced the efficacy of the process. Finally, the identification of the degradation pathway and the biodegradability tests of AOPs treated VFA solutions exhibit promising results concerning the strategy of treatment for similar pollutants of emerging concern

366 Combined exploratory immunophenotyping and transcriptomic tumor analysis in patients treated with OSE2101 vaccine in HLA-A2+ advanced non-small cell lung cancer (NSCLC) from the ATALANTE-1 trial

BackgroundOSE2101 (Tedopi®) is an anticancer vaccine with HLA-A2+ restricted modified epitopes targeting five tumor-associated antigens (TAAs) frequently expressed in lung cancer (CEA, HER2, MAGE2, MAGE3, P53). Step-1 results of the phase III, randomized, open-label ATALANTE-1 study comparing Tedopi® vs standard treatment (SoC) showed a favorable benefit/risk of Tedopi® over SoC (HR 0.71 for overall survival OS) in HLA-A2+ NSCLC patients in 2nd or 3rd line treatment after progression on immune checkpoint blockers (ICB).1 We analyze available tumor biopsies at initial diagnosis from some patients treated with Tedopi® to determine the expression of the 5 TAAs and to identify other tumor factors associated with long-term survival.MethodsTumor biopsies were available for 8 HLA-A2+ (blood test) stage IV NSCLC patients included in the trial. Primary (<12 weeks) and secondary (≥ 12 weeks) resistance to ICB were observed in 3 (38%) and 5 (62%) of patients. Best response to Tedopi® and OS were: 1 partial response (PR) (OS of 33 months), 3 stable disease (SD) (OS of 22, 26 and 41 mo.) and 4 disease progression (PD) (OS of 3, 4, 30 and 31 mo.). HLA-class I, PD-L1, CD8 T-cells, HER2, CEA and P53 tumor expression were evaluated by immunohistochemistry (IHC). NanoString gene expression profiling was performed using the Pan Cancer Immune gene set.ResultsHLA-class I was expressed in all tumor samples. IHC analysis revealed that P53, CEA and HER2 were expressed in 6/7, 5/7 and 0/7 patients, respectively. P53, CEA, HER2, MAGE2, and MAGE3 were detected at RNA level in 5/5 tested patients (table 1). IMMUNOSCORE® IC CD8/PDL1 analysis showed High/High, High/Low and Low/Low scores for 1/7, 1/7 and 5/7 patients, respectively. The High/High IMMUNOSCORE® with a pronounced CD8+ T-cell tumor infiltration was observed in the patient with PR. High percentage of tumor cells expressing P53 (69%–97%) and overexpression of genes associated with activated macrophages (TREM2, MARCO, SLC11A1, CHIT1, SERPINB2) were observed in the PR and SD patients. High IFN-gamma and Expanded Immune Gene Signature scores were observed in long-term survivor patients with secondary resistance to ICB, even after progressive disease.Abstract 366 Table 1Summary of clinical and translational dataCEACarcinoembryonic antigen; HER2: Human Epidermal Growth Factor Receptor-2; ICB: Immune checkpoint blocker; IHC: Immunohistochemistry; ND: Not determined; OS: Overall Survival; Patient ID: Patient identification; PDL1: Programmed death-ligand 1; PFS: Progression-free survival; ssGSEA: Single-sample Gene Set Enrichment Analysis. Blue bars = Length of overall survival; Green bars = Gene Signature upregulation; Red bars = Gene Signature downregulationConclusionsThis study shows that all HLA-A2+ patients (blood test), expressed HLA class I in the tumors at initial diagnosis. Transcriptomic data in the patients that benefited from Tedopi® showed activated macrophage pathway, high IFN-gamma and Expanded Immune Gene Signatures scores. These data will be validated on larger number of patients treated with Tedopi® after the step 2 analysis.AcknowledgementsWe thank Julie Le Boulicaut, François Montestruc and Constant Josse (eXYSTAT, Malakoff, France) for the statistical analysis, and HalioDx for the IHC and NanoString analysis.Trial RegistrationEudraCT number2015-003183-36; NCT number: NCT02654587ReferenceGiaccone, et al. Activity of OSE-2101 in HLA-A2+ non-small cell lung cancer (NSCLC) patients after failure to immune checkpoint inhibitors (ICI): step 1 results of phase III ATALANTE-1 randomised trial. ESMO meeting 2020, abstract #1260MO.Ethics ApprovalThe study protocol and its related documents (including the patient information and informed consent form) received approval from the Institutional Review Board (IRB), and the Competent Authority prior to study initiation.ConsentEach patient gave his/her written informed consent prior to study enrolment

A framework for behavioral studies of social cognition in information systems

Paper presented at ISOneWorld Conference, Las Vegas, NV.This paper examines framing processes in organizational information system definition, acquisition and use. Three theoretical lenses of social cognition are required to understand how individuals and groups frame IS problems and solutions. These are: (i) socially-situated cognition, (ii) socially-shared cognition, and (iii) distributed cognition. These three perspectives are often conflated in studies of that study mental models or framing in an IS context. The separation of analytical "levels" reveals different interiors of the "black box" of organizational IS design and adaptation, which are not well understood. In particular, this methodological framework highlights different assumptions concerning whether mental models are static or dynamic, and whether cognition is a property of individuals, groups, or technological systems

Performance of the ROX index to predict intubation in immunocompromised patients receiving high-flow nasal cannula for acute respiratory failure

Background Delayed intubation is associated with high mortality. There is a lack of objective criteria to decide the time of intubation. We assessed a recently described combined oxygenation index (ROX index) to predict intubation in immunocompromised patients. The study is a secondary analysis of randomized trials in immunocompromised patients, including all patients who received high-flow nasal cannula (HFNC). The first objective was to evaluate the accuracy of the ROX index to predict intubation for patients with acute respiratory failure. Results In the study, 302 patients received HFNC. Acute respiratory failure was mostly related to pneumonia (n = 150, 49.7%). Within 2 (1-3) days, 115 (38.1%) patients were intubated. The ICU mortality rate was 27.4% (n = 83). At 6 h, the ROX index was lower for patients who needed intubation compared with those who did not [4.79 (3.69-7.01) vs. 6.10 (4.48-8.68), p < 0.001]. The accuracy of the ROX index to predict intubation was poor [AUC = 0.623 (0.557-0.689)], with low performance using the threshold previously found (4.88). In multivariate analysis, a higher ROX index was still independently associated with a lower intubation rate (OR = 0.89 [0.82-0.96], p = 0.04). Conclusion A ROX index greater than 4.88 appears to have a poor ability to predict intubation in immunocompromised patients with acute respiratory failure, although it remains highly associated with the risk of intubation and may be useful to stratify such risk in future studies

Surdosage aux anti-vitamines K (étude rétrospective aux urgences du C.H.U. de Limoges en 2001)

LIMOGES-BU Médecine pharmacie (870852108) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Entre effervescence et ambivalences : déclinaisons du patrimoine

International audienc

Automatic Optimal Command for the Linearization of the CMUT Output

International audienceCapacitive micromachined ultrasonic transducer (cMUT) is a promising alternative to piezoelectric transducers. However, its nonlinear behavior could limit its use in medical ultrasound technology, mainly for therapy and non-linear imaging. Several linearization methods based on a precompensation applied to the input voltage have been proposed to cancel out the harmonic components of the cMUT output signal. An approach based on the principle of the Wiener filter has first been proposed. A second technique empirically adds a third harmonic component 3f0 to the useful input signal centered at the frequency f0 in order to cancel out only the second harmonic. Nevertheless, these techniques are efficient while the cMUT works in narrowband operating conditions only. A third method based its analysis on an equivalent non-linear electro-acoustic scheme of the cMUT. From this scheme, the determination of the optimal “input” signal able to suppress harmonic components is then straightforward. Operating conditions are here not restricted but the non-linear model applies to a single cell only, without considering a population of cMUTs, as in the case of one element of array. Finally, Satir and Degertekin have proposed to add a passive component in series with the cMUT in order to convert the input voltage control into an input charge control. However, none of these methods is entirely satisfactory, because they require a priori knowledge and no method is automatic. In this paper, we proposed a novel method to linearize the signal transmitted by cMUT. The method aims to automatically provide an optimal input signal eliminating the nonlinear component of the cMUT output. It consists in choosing first a target signal, with the desired spectrum or temporal shape. This target signal is used as the input excitation signal of the cMUT but after being filtered with a nonlinear autoregressive filter. The output of this filter is the optimal signal and its parameters describe the optimal command. A simplex algorithm is used for seeking the filter parameters. The method was tested and validated with simulations and experiments, using spectral and temporal targets. The results have shown that the nonlinear components were reduced of 97% in comparison with the case without compensation

Ambivalences patrimoniales au Sud : mises en scène et jeux d’acteurs

International audienceEn s'appuyant sur des objets extrêmement variés (territoires, ressources végétales ou animales, archives ou collections, sites archéologiques ou éléments immatériels dérivés de la culture et de l’histoire, comme l'esclavage ou encore la gastronomie), l’ouvrage se penche sur les dynamiques de patrimonialisation et les multiples contradictions, conflits et compétitions, parfois irréductibles, que celles-ci provoquent.D'un côté, les traités internationaux sur la diversité génétique et le patrimoine naturel ou culturel, par leurs implications éthiques et juridiques, notamment en termes de propriété intellectuelle, sont l'objet d'interprétations contrastées, signalant la confrontation entre droit international, politiques nationales et règles locales. D’un autre côté, dans les espaces stratégiques, tels que les parcs nationaux, se nouent des enjeux multiples et changeants avec les politiques qui les animent.Quant aux sites archéologiques, ils s'inscrivent souvent dans une double logique de concurrence : les patrimoines universels que la diachronie révèle s’opposent à d'autres usages, en particulier économiques, du territoire.Toutes ces constructions patrimoniales ont en commun d'impliquer une mise en scène visant à les faire voir et reconnaître, mises en scène qu'orchestrent ou instrumentalisent une série d'acteurs, institutions, communautés locales voire les chercheurs eux-mêmes. L'ouvrage parcourt ainsi, à travers des exemples puisés dans différents terrains, Cambodge, Zanzibar, Guinée et Guinée-Bissau, Ethiopie, Sénégal, Equateur, Lybie, Tunisie mais aussi les salins narbonnais, ou encore les coulisses des grandes expéditions naturalistes françaises, les logiques, ambiguïtés et polyvalences de la patrimonialisation. Il confirme au final la vocation particulièrement stratégique du patrimoine, et révèle les multiples tensions et mutations que son invocation enclenche dans les territoires et les sociétés du monde