958 results on '"A. Focsa"'
Search Results
102. Link between Polycyclic Aromatic Hydrocarbon Size and Aqueous Alteration in Carbonaceous Chondrites Revealed by Laser Mass Spectrometry
- Author
-
Slavicinska, Katerina, primary, Duca, Dumitru, additional, Egorov, Dmitrii, additional, Mitra, Tirthankar, additional, Carpentier, Yvain, additional, Focsa, Cristian, additional, Bennett, Christopher J., additional, and Pirim, Claire, additional
- Published
- 2022
- Full Text
- View/download PDF
103. The Influence of Periodontal Disease on Oral Health Quality of Life in Patients with Cardiovascular Disease: A Cross-Sectional Observational Single-Center Study
- Author
-
Lazureanu, Pompilia Camelia, primary, Popescu, Florina Georgeta, additional, Stef, Laura, additional, Focsa, Mircea, additional, Vaida, Monica Adriana, additional, and Mihaila, Romeo, additional
- Published
- 2022
- Full Text
- View/download PDF
104. Optimization of the Synthesis of Diclofenac Derivatives with Hydrazone Structure and In Vitro Evaluation of the Anti-Inflammatory Potential
- Author
-
Alin Viorel Focsa, Andreea Teodora Iacob, Loredana Andriescu, Maria Apotrosoaei, Lenuta Profire, Sylvain Routier, Alexandru Sava, Ioana Vasincu, Frédéric Buron, and Sandra Constantin
- Subjects
chemistry.chemical_classification ,Process equipment ,medicine.drug_class ,Materials Science (miscellaneous) ,Process Chemistry and Technology ,General Engineering ,Hydrazone ,General Chemistry ,General Medicine ,Combinatorial chemistry ,General Biochemistry, Genetics and Molecular Biology ,Anti-inflammatory ,In vitro ,Diclofenac ,chemistry ,Petrochemistry ,Materials Chemistry ,medicine ,General Pharmacology, Toxicology and Pharmaceutics ,medicine.drug - Abstract
The aim of the study was to optimize the synthesis of diclofenac derivative with hydrazones structure in order to obtain higher yields and purity by variation of different parameters such as: ratio between reactants, solvent, catalyst, temperature, time of reaction and method used. The anti-inflammatory effects of diclofenac derivatives were evaluated using in vitro assays: albumin denaturation and erythrocyte membrane stability. The obtained results showed that the effect of the tested derivatives is increasing with the concentration, the best results being obtained at the concentration of 125 �g/mL (albumin denaturation assay), respectively 111.11 �g/mL (erythrocyte membrane stability assay). The most active compound was 4d which showed the highest inhibition effect on albumin denaturation and an appreciable effect on erythrocyte membrane stability, in comparation with diclofenac, used as drug reference.
- Published
- 2020
- Full Text
- View/download PDF
105. Treatment of Epilepsy Associated with Common Chromosomal Developmental Diseases
- Author
-
Aurora Arghir, Dan Riga, Magdalena Budisteanu, Alexandru Daniel Jurcă, Ina Ofelia Focsa, Sorina Mihaela Papuc, Sorin Riga, and Claudia Jurca
- Subjects
0303 health sciences ,chromosomal diseases ,General Immunology and Microbiology ,Exacerbation ,QH301-705.5 ,General Neuroscience ,epileptic seizures ,Context (language use) ,Biology ,Bioinformatics ,medicine.disease ,Chromosomal diseases ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Epilepsy ,0302 clinical medicine ,Genetic etiology ,EEG Findings ,medicine ,antiepileptic drugs ,Biology (General) ,General Agricultural and Biological Sciences ,030217 neurology & neurosurgery ,030304 developmental biology ,Research Article - Abstract
Chromosomal diseases are heterogeneous conditions with complex phenotypes, which include also epileptic seizures. Each chromosomal syndrome has a range of specific characteristics regarding the type of seizures, EEG findings and specific response to antiepileptic drugs, significant in the context of the respective genetic etiology. Therefore, it is very important to know these particularities, in order to avoid an exacerbation of seizures or some side effects. In this paper we will present a review of the epileptic seizures and antiepileptic treatment in some of the most common chromosomal syndromes.
- Published
- 2020
106. Chemical discrimination of the particulate and gas phases of miniCAST exhausts using a two-filter collection method
- Author
-
L. D. Ngo, D. Duca, Y. Carpentier, J. A. Noble, R. Ikhenazene, M. Vojkovic, C. Irimiea, I. K. Ortega, G. Lefevre, J. Yon, A. Faccinetto, E. Therssen, M. Ziskind, B. Chazallon, C. Pirim, and C. Focsa
- Subjects
lcsh:TA715-787 ,lcsh:Earthwork. Foundations ,lcsh:TA170-171 ,lcsh:Environmental engineering - Abstract
Combustion of hydrocarbons produces both particulate- and gas-phase emissions responsible for major impacts on atmospheric chemistry and human health. Ascertaining the impact of these emissions, especially on human health, is not straightforward because of our relatively poor knowledge of how chemical compounds are partitioned between the particle and gas phases. Accordingly, we propose coupling a two-filter sampling method with a multi-technique analytical approach to fully characterize the particulate- and gas-phase compositions of combustion by-products. The two-filter sampling method is designed to retain particulate matter (elemental carbon possibly covered in a surface layer of adsorbed molecules) on a first quartz fiber filter while letting the gas phase pass through and then trap the most volatile components on a second black-carbon-covered filter. All samples thus collected are subsequently subjected to a multi-technique analytical protocol involving two-step laser mass spectrometry (L2MS), secondary ion mass spectrometry (SIMS), and micro-Raman spectroscopy. Using the combination of this two-filter sampling–multi-technique approach in conjunction with advanced statistical methods, we are able to unravel distinct surface chemical compositions of aerosols generated with different set points of a miniCAST burner. Specifically, we successfully discriminate samples by their volatile, semi-volatile, and non-volatile polycyclic aromatic hydrocarbon (PAH) contents and reveal how subtle changes in combustion parameters affect particle surface chemistry.
- Published
- 2020
107. Preliminary results on the chemical composition of the Lepidorhombus boscii (Risso, 1810) otolith from the Adriatic sea
- Author
-
Ugrin, Nika, Mitra, Tirthankar, Carpentier, Yvain, Pirim, Claire, Salamon, Krešimir, Jakovljević, Suzana, Vojković, Marin, Cristian Focsa, Krstulović Šifner, Svjetlana, Ivanić, Maja, Fiket, Željka, Furdek Turk, Martina, and Vdović Neda
- Subjects
Lepidorhombus boscii ,Adriatic sea ,otolith ,scanning electron microscopy ,X-ray diffraction ,mass spectrometry - Abstract
Otoliths are a part of the fish inner ear involved in sound reception, balance perception and orientation. Saggital otoliths of teleost fish mainly consist of calcium carbonate in the form of aragonite. However, there are abnormal otoliths that contain other polymorphs, such as calcite, vaterite or their combinations. This preliminary study represents the first record and investigation of Lepidorhombus boscii otoliths including those irregularly shaped and characterized by surface deformations. These can arise due to stressful conditions, high population density, temperature fluctuations, disease or pollution, which can cause structural or physiological changes that affect the formation of otoliths. In addition to morphological features, polymorphs of calcium carbonate have an influence on the elemental composition of otoliths. The morphology and chemical composition of L. boscii saggital otolith were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and by two step laser desorption ionization mass spectrometry (L2MS). L2MS was used to analyse the surface chemical composition of the otoliths, confirming the presence of inorganic and organic compounds in the otolith matrix. Tuning the desorption fluencies to maximize the metal containing components (K, Ca, Cu, Ag, Sr), shows an abundance of pure metallic, oxidized and hydroxidized species. XRD was used to analyse the crystal structure, while SEM was used to photograph the surfaces of normal and abnormal otoliths (aragonite and calcite) between males and females. This research provided a preliminary insight into the concentrations of chemical elements deposited on the otoliths of individuals of this species in the central Adriatic Sea. Although the number of analyzed samples is small, the results are promising. They represent a starting point for the future research, that should be based on a larger number of samples from more locations These results could be used to get a better insight into movement patterns and possibly for determination of the origin of this species.
- Published
- 2022
108. A Compressive-Sensing Approach for Opportunistic Bistatic SAR Imaging Enhancement by Harnessing Sparse Multiaperture Data
- Author
-
Mihai Datcu, Andrei Anghel, and Adrian Focsa
- Subjects
Signal reconstruction ,Computer science ,Bistatic ,Transmitter ,Context (language use) ,multiaperture ,Azimuth ,Bistatic radar ,Interferometry ,Compressed sensing ,compressive sensing (CS) ,opportunistic acquisition ,Chirp ,General Earth and Planetary Sciences ,Electrical and Electronic Engineering ,Algorithm - Abstract
This article introduces a compressive sensing (CS)-based approach for increasing bistatic synthetic aperture radar (SAR) imaging quality in the context of a multiaperture acquisition. The analyzed data were recorded over an opportunistic bistatic setup including a stationary ground-based-receiver opportunistic C-band bistatic SAR differential interferometry (COBIS) and Sentinel-1 C-band transmitter. Since the terrain observation by progressive scans (TOPS) mode is operated, the receiver can record synchronization pulses and echoed signals from the scene during many apertures. Hence, it is possible to improve the azimuth resolution by exploiting the multiaperture data. The recorded data are not contiguous and a naive integration of the chopped azimuth phase history would generate undesired grating lobes. The proposed processing scheme exploits the natural sparsity characterizing the illuminated scene. For azimuth profiles recovery greedy, convex, and nonconvex CS solvers are analyzed. The sparsifying basis/dictionary is constructed using the synthetically generated azimuth chirp derived considering Sentinel-1 orbital parameters and COBIS position. The chirped-based CS performance is further put in contrast with a Fourier-based CS method and an autoregressive model for signal reconstruction in terms of scene extent limitations and phase restoration efficiency. Furthermore, the analysis of different receiver-looking scenarios conducted to the insertion in the processing chain of a direct and an inverse Keystone transform for range cell migration (RCM) correction to cope with squinted geometries. We provide an extensive set of simulated and real-world results that prove the proposed workflow is efficient both in improving the azimuth resolution and in mitigating the sidelobes.
- Published
- 2022
109. Emission Inventories of Volatile Organic Compounds from Sewage Sludge
- Author
-
Kawssar Haider, F. Lafouge, Y. Carpentier, S. Houot, D. Petitprez, B. Loubet, C. Focsa, and Raluca Ciuraru
- Published
- 2022
- Full Text
- View/download PDF
110. Topological spaces. Applications - dissertation paper presentation / Spatii topologice. Aplicatii – prezentare lucrare de disertatie
- Author
-
Focsa, Maria Diana and Croitoru, Anca
- Published
- 2022
- Full Text
- View/download PDF
111. CARACTÉRISATION DES ÉMISSIONS DE COMPOSÉS ORGANIQUES VOLATILS DES DÉJECTIONS ANIMALES ET DE LEUR RÉACTIVITÉ À L'OZONE
- Author
-
K.M. HAIDER, F. LAFOUGE, C. DECUQ, B. ESNAULT, A. FORTINEAU, Y. CARPENTIER, D. PETITPREZ, C. FOCSA, and R. CIURARU
- Subjects
aérosol organique secondaire ,produits résiduaires organiques ,spectrométrie de masse ,organic waste products ,volatile organic compounds ,ozone reactivity ,réactivité à l'ozone ,secondary organic aerosol ,composés organiques volatils ,mass spectrometry - Abstract
Les composés organiques volatils (COV) sont importants pour la production d'ozone et des précurseurs critiques des aérosols organiques secondaires dans l'atmosphère. Les activités agricoles telles que l'utilisation d'engrais minéraux, l'élevage et l'épandage de fumier animal contribuent à la pollution atmosphérique. L'épandage de fumier animal sur le sol est associé à divers polluants tels que les aérosols primaires, l'ammoniac et le sulfure d'hydrogène, ainsi qu'aux émissions de COV. Dans ce contexte, une étude expérimentale a été menée sur différents types de fumier (vache, cheval, brebis et chèvre) collectés à Grignon (Paris, France). Les échantillons ont été placés dans des chambres de simulation atmosphérique et les émissions en phase gazeuse de composés organiques volatils et leurs produits d'oxydation résultant de réactions d'ozonolyse ont été caractérisés par spectrométrie de masse. Plus de deux cents COV ont été détectés et quantifiés. Les familles de COV détectées comprenaient des composés oxygénés, azotés, soufrés, des composés azotées et oxygénées et des hydrocarbures. Les composés oxygénés se sont avérés être les COV dominants dans tous les échantillons. Lorsqu'ils sont exposés à l'ozone, seuls les échantillons de fumier de vache ont montré une réactivité due à la présence du scatole (C9H9N). Cependant, aucune formation de particules n'a été observée dans nos conditions expérimentales. Cela est principalement dû aux faibles émissions de SO2 des échantillons, car le SO2 et le scatole jouent un rôle clé dans la formation d'aérosols organiques secondaires. Les données expérimentales obtenues dans le cadre de cette étude aideront à améliorer les inventaires des émissions par les activités agricoles et fourniront des informations sur les COV d'origine agricole qui peuvent servir de précurseurs d'aérosols organiques secondaires en présence de photo-oxydants, comme l'ozone., Volatile organic compounds (VOCs) are significant to ozone production and critical precursors of secondary organic aerosols in the atmosphere. Agricultural activities such as the use of mineral fertilizers, livestock production and land application of animal manure contribute to atmospheric pollution. Land application of animal manure is associated with variety of pollutants such as primary aerosols, ammonia, and hydrogen sulfide as well as VOC emissions. In this context, an experimental study was carried out on different animal manures (e.g. cow, horse, sheep, and goat) taken from Grignon (Paris, France). The samples were placed in atmospheric simulation chambers and the gas phase emissions of VOCs and their oxidation products resulting from ozonolysis reactions were characterized using mass spectrometric tools. More than two hundred VOCs were detected and quantified. The detected VOCs families included oxygenated compounds, nitrogen-containing compounds, sulfur-containing compounds, nitrogen and oxygen containing compounds and hydrocarbons. Oxygenated compounds were found to be the dominating VOCs in all samples. When exposed to ozone, only cow manure samples showed reactivity due to skatole (C9H9N). However, no particle formation was observed in our experimental conditions. This is mainly explained by low SO2 emissions from the samples, as SO2 together with skatole play a key role in secondary organic aerosol formation. The experimental dataset obtained in this study will help to improve emission inventories for agricultural activities and provide deeper insights into potential VOCs that can serve as secondary organic aerosol precursors in the presence of photo-oxidants (e.g. ozone).
- Published
- 2022
- Full Text
- View/download PDF
112. Topological spaces. Applications - dissertation paper / Spatii topologice. Aplicatii – lucrare de disertatie
- Author
-
Focsa, Maria Diana
- Published
- 2022
- Full Text
- View/download PDF
113. High-sensitivity detection of polycyclic aromatic hydrocarbons adsorbed onto soot particles using laser desorption/laser ionization/time-of-flight mass spectrometry: An approach to studying the soot inception process in low-pressure flames
- Author
-
Faccinetto, Alessandro, Desgroux, Pascale, Ziskind, Michael, Therssen, Eric, and Focsa, Cristian
- Published
- 2011
- Full Text
- View/download PDF
114. A Compressive-Sensing Approach for Opportunistic Bistatic SAR Imaging Enhancement by Harnessing Sparse Multiaperture Data
- Author
-
Focsa, Adrian, primary, Anghel, Andrei, additional, and Datcu, Mihai, additional
- Published
- 2022
- Full Text
- View/download PDF
115. Emission Inventories of Volatile Organic Compounds from Sewage Sludge
- Author
-
Haider, Kawssar, primary, Lafouge, F., additional, Carpentier, Y., additional, Houot, S., additional, Petitprez, D., additional, Loubet, B., additional, Focsa, C., additional, and Ciuraru, Raluca, additional
- Published
- 2022
- Full Text
- View/download PDF
116. Attention networks and the intrinsic network structure of the human brain
- Author
-
David Nothdurfter, Antonia Focsa, Sebastian Markett, Martin Reuter, and Philippe Jawinski
- Subjects
Adult ,Male ,cognition ,Dissociation (neuropsychology) ,Computer science ,attention network test ,Task (project management) ,Young Adult ,Neuroimaging ,Connectome ,Humans ,Attention ,Radiology, Nuclear Medicine and imaging ,ddc:610 ,Set (psychology) ,Cognitive science ,Cerebral Cortex ,Brain Mapping ,Resting state fMRI ,Radiological and Ultrasound Technology ,functional connectivity ,Magnetic Resonance Imaging ,Focus (linguistics) ,attention network ,Neurology ,Anticipation (artificial intelligence) ,Female ,Neurology (clinical) ,Nerve Net ,Anatomy ,Construct (philosophy) ,610 Medizin und Gesundheit ,Psychomotor Performance - Abstract
Attention network theory states that attention is not a unified construct but consists of three independent systems that are supported by separable distributed networks: an alerting network to deploy attentional resources in anticipation of upcoming events, an orienting network to direct attention to a cued location, and a control network to select relevant information at the expense of concurrently available information. Ample behavioral and neuroimaging evidence supports the dissociation of the three attention domains. The strong assumption that each attentional system is realized through a separable network, however, raises the question how these networks relate to the intrinsic network structure of the brain.Our understanding of brain networks has advanced majorly in the past years due to the increasing focus on brain connectivity. It is well established that the brain is intrinsically organized into several large-scale networks whose modular structure persists across task states. Existing proposals on how the presumed attention networks relate to intrinsic networks rely mostly on anecdotal and partly contradictory arguments. We addressed this issue by mapping different attention networks with highest spatial precision at the level of cifti-grayordinates. Resulting group maps were compared to the group-level topology of 23 intrinsic networks which we reconstructed from the same participants’ resting state fMRI data. We found that all attention domains recruited multiple and partly overlapping intrinsic networks and converged in the dorsal fronto-parietal and midcingulo-insular network. While we observed a preference of each attentional domain for its own set of intrinsic networks, implicated networks did not match well to those proposed in the literature. Our results indicate a necessary refinement of the attention network theory.
- Published
- 2021
117. Pulsed laser deposition of rare-earth-doped gallium lanthanum sulphide chalcogenide glass thin films
- Author
-
Pompilian, O. G., Dascalu, G., Mihaila, I., Gurlui, S., Olivier, M., Nemec, P., Nazabal, V., Cimpoesu, N., and Focsa, C.
- Published
- 2014
- Full Text
- View/download PDF
118. Laser absorption spectroscopy on a transient aluminum plasma generated by excimer laser ablation
- Author
-
C. Ursu, P. Nica, G.B. Rusu, C. Vitelaru, Gh. Popa, and C. Focsa
- Subjects
Instrumentation ,Spectroscopy ,Atomic and Molecular Physics, and Optics ,Analytical Chemistry - Published
- 2022
- Full Text
- View/download PDF
119. Effect of MW-ECR plasma hydrogenation on polysilicon films based solar cells
- Author
-
Madi, D., Focsa, A., Roques, S., Schmitt, S., Slaoui, A., and Birouk, B.
- Published
- 2010
- Full Text
- View/download PDF
120. Evidence on the formation of dimers of polycyclic aromatic hydrocarbons in a laminar diffusion flame
- Author
-
Alessandro Faccinetto, Claire Pirim, Xavier Mercier, Mario Commodo, Cristian Focsa, Nicolas Nuns, Andrea D’Anna, Cornelia Irimiea, Patrizia Minutolo, Pascale Desgroux, Yvain Carpentier, Université de Lille, CNRS, Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 [PC2A], DMPE, ONERA, Université Paris Saclay (COmUE) [Palaiseau], Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM], Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 (PC2A), Université de Lille-Centre National de la Recherche Scientifique (CNRS), DMPE, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Istituto di Ricerche sulla Combustione, Napoli, Italy (IRC-CNR), University of Naples Federico II, Institut Chevreul - FR2638, Université d'Artois (UA)-Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), ANR: 11-LABX-0005,Cappa,Physiques et Chimie de l'Environnement Atmosphérique(2011), Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche [Napoli] (CNR), Università degli studi di Napoli Federico II, Institut Michel Eugène Chevreul - FR 2638 (IMEC), Université d'Artois (UA)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centrale Lille Institut (CLIL), University of Naples Federico II = Università degli studi di Napoli Federico II, Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Faccinetto, A., Irimiea, C., Minutolo, P., Commodo, M., D'Anna, A., Nuns, N., Carpentier, Y., Pirim, C., Desgroux, P., Focsa, C., and Mercier, X.
- Subjects
Diffusion ,polycyclic aromatic hydrocarbons ,Nucleation ,02 engineering and technology ,010402 general chemistry ,Photochemistry ,Combustion ,medicine.disease_cause ,01 natural sciences ,Biochemistry ,soot ,Methane ,lcsh:Chemistry ,chemistry.chemical_compound ,Materials Chemistry ,medicine ,Environmental Chemistry ,[CHIM]Chemical Sciences ,ComputingMilieux_MISCELLANEOUS ,[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph] ,Chemistry ,Diffusion flame ,Laminar flow ,General Chemistry ,021001 nanoscience & nanotechnology ,Soot ,0104 chemical sciences ,lcsh:QD1-999 ,Covalent bond ,0210 nano-technology ,inception - Abstract
The role of polycyclic aromatic hydrocarbons (PAHs) in the formation of nascent soot particles in flames is well established and yet the detailed mechanisms are still not fully understood. Here we provide experimental evidence of the occurrence of dimerization of PAHs in the gas phase before soot formation in a laminar diffusion methane flame, supporting the hypothesis of stabilization of dimers through the formation of covalent bonds. The main findings of this work derive from the comparative chemical analysis of samples extracted from the gas to soot transition region of a laminar diffusion methane flame, and highlight two different groups of hydrocarbons that coexist in the same mass range, but show distinctly different behavior when processed with statistical analysis. In particular, the identified hydrocarbons are small-to-moderate size PAHs (first group) and their homo- and heterodimers stabilized by the formation of covalent bonds (second group). A comprehensive understanding of soot nucleation in flame combustion is still lacking. Here the authors identify homo- and heterodimers of small-to-moderate size polycyclic aromatic hydrocarbons in the gas to soot transition region of a laminar diffusion methane flame as viable intermediates in the soot nucleation process.
- Published
- 2020
- Full Text
- View/download PDF
121. The UNREAL (Unveiling nucleation mechanism in aircraft engine exhaust and its link with fuel composition) project: Results from simulation chamber and reactor experiments
- Author
-
Ortega, Ismael K., Mathieu Cazaunau, Farah, A., Singh, A., Nicolas Karoski, Rafael Barrellon-Vernay, Jonathan Duplissy, Bergé, A., Joel Brito, Berthier, A., David Delhaye, Jean-Eudes Petit, Alexandre Albinet, Sicard, M., Carpentier, Y., Raepsaet, B., Ser, F., Kulmala, M., Véronique Riffault, Cristian Focsa, Jean-Francois Doussin, DMPE, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Ecole nationale supérieure Mines-Télécom Lille Douai (IMT Nord Europe), Institut Mines-Télécom [Paris] (IMT), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut National de l'Environnement Industriel et des Risques (INERIS), Helsinki Institute of Physics (HIP), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Centre for Energy and Environment (CERI EE - IMT Nord Europe), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), ANR-18-CE22-0019,UNREAL,Dévoilement du mécanisme de nucléation dans les gaz d'échappement des moteurs d'avion et de son lien avec la composition du carburant(2018), ANR-11-LABX-0005,Cappa,Physiques et Chimie de l'Environnement Atmosphérique(2011), Civs, Gestionnaire, APPEL À PROJETS GÉNÉRIQUE 2018 - Dévoilement du mécanisme de nucléation dans les gaz d'échappement des moteurs d'avion et de son lien avec la composition du carburant - - UNREAL2018 - ANR-18-CE22-0019 - AAPG2018 - VALID, and Physiques et Chimie de l'Environnement Atmosphérique - - Cappa2011 - ANR-11-LABX-0005 - LABX - VALID
- Subjects
[SDE] Environmental Sciences ,[SDE]Environmental Sciences - Abstract
International audience; Aviation emissions are not limited to greenhouse gases like CO2 but include other gases as well, such as nitrogen oxides (NOx) or sulfur oxides (SOx) and volatile and non-volatile particulate matter (vPM and nvPM respectively). Sulfuric acid formed in the engine exhaust seems to be linked to the formation of vPM. However, the amount of sulfur present in the fuel converted to sulfuric acid in the exhaust is too small to explain the amount of vPM observed (Vancassel et al. 2004). Organic compounds emitted by the engine are among the most suitable candidates to explain the formation of vPM in the engine exhaust (Sorokin et al. 2001), but the molecular mechanisms behind this phenomenon are still unknown.
- Published
- 2021
122. Impact of fuel composition on primary and secondary aeronautic emissions: gaseous and particulate chemical characterization at molecular level
- Author
-
Rafael Barrellon-Vernay, Ortega, Ismael K., David Delhaye, Berthier, A., Egorov, D., Mitra, T., Mathieu Cazaunau, Bergé, A., Pangui, E., Alexandre Albinet, Jean-Eudes Petit, Singh, A., Véronique Riffault, Joel Brito, Farah, A., Ser, F., Jean-Francois Doussin, Cristian Focsa, DMPE, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut National de l'Environnement Industriel et des Risques (INERIS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre for Energy and Environment (CERI EE - IMT Nord Europe), Ecole nationale supérieure Mines-Télécom Lille Douai (IMT Nord Europe), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Civs, Gestionnaire, and Institut Mines-Télécom [Paris] (IMT)
- Subjects
[SDE] Environmental Sciences ,[SDE]Environmental Sciences - Abstract
International audience; Aviation has been, before the sanitary crisis, one of the strongest growing transport sectors. Despite this crisis, this trend is predicted to continue (Neu 2020). One of the actual concerns of aviation industry is to reduce its impact on climate and air quality using for example Sustainable Aviation Fuels (SAF). As part of the UNREAL (Unveiling Nucleation mechanism in aiRcraft Engine exhAust and its Link with fuel composition) project, the objective of this work was to study and compare the chemical pattern, at a molecular level, of the gaseous and particulate phases of primary as well as secondary emissions from various aircraft fuels with distinct compositions.
- Published
- 2021
123. On the Interferometric Capabilities of the Pulson P440 UWB Radar
- Author
-
Damian Gorgoteanu, Stefan-Adrian Toma, and Adrian Focsa
- Subjects
Synthetic aperture radar ,Interferometric phase ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,Measure (physics) ,Displacement (vector) ,law.invention ,Interferometry ,Optics ,law ,Radar ,business ,Nonlinear Sciences::Pattern Formation and Solitons ,Synthetic aperture radar interferometry ,Robotic arm ,Physics::Atmospheric and Oceanic Physics ,Geology - Abstract
In this paper are presented target displacement measurements using synthetic aperture radar interferometry, with the Pulson P440 radar module. The synthetic aperture is formed by automatically moving the radar with the help of a robotic arm. We show that by applying an appropriate interferometric phase correction, we can measure target displacement with the Pulson P440.
- Published
- 2021
- Full Text
- View/download PDF
124. Attention networks and the intrinsic network structure of the human brain
- Author
-
Markett, Sebastian, primary, Nothdurfter, David, additional, Focsa, Antonia, additional, Reuter, Martin, additional, and Jawinski, Philippe, additional
- Published
- 2021
- Full Text
- View/download PDF
125. Direct Water-Assisted Laser Desorption/Ionization Mass Spectrometry Lipidomic Analysis and Classification of Formalin-Fixed Paraffin-Embedded Sarcoma Tissues without Dewaxing
- Author
-
Ogrinc, Nina, primary, Caux, Pierre-Damien, additional, Robin, Yves-Marie, additional, Bouchaert, Emmanuel, additional, Fatou, Benoit, additional, Ziskind, Michael, additional, Focsa, Cristian, additional, Bertin, Delphine, additional, Tierny, Dominique, additional, Takats, Zoltan, additional, Salzet, Michel, additional, and Fournier, Isabelle, additional
- Published
- 2021
- Full Text
- View/download PDF
126. Influence of rare earth addition in cobalt ferrite thin films obtained by pulsed laser deposition
- Author
-
V. Trandafir, Silviu Gurlui, Georgiana Bulai, Cristian Focsa, Stefan Andrei Irimiciuc, and L. Ursu
- Subjects
010302 applied physics ,Ionic radius ,Materials science ,Dopant ,Silicon ,Process Chemistry and Technology ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Pulsed laser deposition ,Crystallinity ,symbols.namesake ,Lattice constant ,chemistry ,0103 physical sciences ,Materials Chemistry ,Ceramics and Composites ,symbols ,Thin film ,0210 nano-technology ,Raman spectroscopy - Abstract
The influence of rare earth (RE = Dy, Gd, Yb) ion doping on the structural, magnetic and optical properties of cobalt ferrite thin films was studied. CoFe 2-x RE x O 4 (x = 0.01; 0.03; 0.05; 0.1; 0.2; 0.3) films were obtained by pulsed laser deposition on silicon substrates. The X-ray diffraction and Raman spectroscopy results on the bulk materials, which were used as targets during deposition, revealed the formation of residual phases as the concentration of RE dopant was increased. However, the annealed thin films presented diffraction lines and vibrational modes corresponding only to cobalt ferrite. A lower crystallinity of the deposited samples was observed when higher RE concentrations were used. Due to the substitution of Fe by RE elements which possess large ionic radii, the lattice parameter of the thin films presented a monotonous increase. The magnetic response of the nanostructures was correlated to the magnetic moment of the RE dopant and to the structural properties of the films. The optical bandgaps derived from the reflectance spectra presented an increasing trend as the Yb and Dy concentrations were augmented.
- Published
- 2019
- Full Text
- View/download PDF
127. Oscillatory regimes of Langmuir probe current in femtosecond laser-produced plasmas: Experimental and theoretical investigations
- Author
-
Maricel Agop, P. Nica, Silviu Gurlui, and Cristian Focsa
- Subjects
Physics ,Ambipolar diffusion ,Oscillation ,General Physics and Astronomy ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,Plasma ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Charged particle ,0104 chemical sciences ,Surfaces, Coatings and Films ,symbols.namesake ,Electric field ,Femtosecond ,symbols ,Langmuir probe ,Atomic physics ,0210 nano-technology ,Current density - Abstract
We investigate the oscillatory regimes of the Langmuir probe current recorded for the electrical characterization of femtosecond laser-produced plasma. The influence of metallic target biasing, which can perturb the ambipolar electric field generated through the charge separation at early stages of the expansion, is also studied. Two distinct behaviors are evidenced, and they point to the existence of two plasma structures: a fast one consisting in promptly ejected highly charged particles, and a slow “tail” of thermalized particles. Theoretically, a non-differentiable model which involves two scale resolutions is developed. Assuming the principle of scale resolution superposition, the current density at global scale is expressed as the sum of the current density at Coulomb and the thermal scale resolutions, in agreement with the experimental data. Interestingly, the theoretical estimation of oscillation frequencies shows a correspondence with the filling factor hierarchy in the fractional quantum Hall effect.
- Published
- 2019
- Full Text
- View/download PDF
128. Dealing with complexity: general discussion
- Author
-
Anneke Lubben, Pierre Giusti, Philippe Schmitt-Kopplin, Dumitru Duca, Ljiljana Paša-Tolić, Ruth Godfrey, Carlos Afonso, Cristian Focsa, Royston Goodacre, Antony N. Davies, Ryan P. Rodgers, Peter J. Schoenmakers, Nicholle G. A. Bell, Norbert Hertkorn, Adrien Le Guennec, Dušan Uhrín, Jeroen J. Jansen, Stephen Summerfield, Donald Jones, Caroline Gauchotte-Lindsay, Fleur H. M. van Zelst, Jeffrey A. Hawkes, Christopher P. Rüger, Danilo Sciarrone, Mark P. Barrow, and William Kew
- Subjects
Environmental science ,Physical and Theoretical Chemistry - Published
- 2019
- Full Text
- View/download PDF
129. Experimental comparison of soot formation in turbulent flames of Diesel and surrogate Diesel fuels
- Author
-
Lemaire, R., Faccinetto, A., Therssen, E., Ziskind, M., Focsa, C., and Desgroux, P.
- Published
- 2009
- Full Text
- View/download PDF
130. Characterisation of particulate matter and gaseous emissions from a large ship diesel engine
- Author
-
Moldanová, Jana, Fridell, Erik, Popovicheva, Olga, Demirdjian, Benjamin, Tishkova, Victoria, Faccinetto, Alessandro, and Focsa, Cristian
- Published
- 2009
- Full Text
- View/download PDF
131. A comparative study of SiO 2 deposited by PECVD and thermal method as passivation for multicrystalline silicon solar cells
- Author
-
Panek, P., Drabczyk, K., Focsa, A., and Slaoui, A.
- Published
- 2009
- Full Text
- View/download PDF
132. Surface passivation at low temperature of p- and n-type silicon wafers using a double layer a-Si:H/SiNx:H
- Author
-
Focsa, A., Slaoui, A., Charifi, H., Stoquert, J.P., and Roques, S.
- Published
- 2009
- Full Text
- View/download PDF
133. Laser ablation of As xSe 100− x chalcogenide glasses: Plume investigations
- Author
-
Focsa, C., Nemec, P., Ziskind, M., Ursu, C., Gurlui, S., and Nazabal, V.
- Published
- 2009
- Full Text
- View/download PDF
134. Space- and time-resolved optical diagnosis for the study of laser ablation plasma dynamics
- Author
-
Ursu, C., Gurlui, S., Focsa, C., and Popa, G.
- Published
- 2009
- Full Text
- View/download PDF
135. Solid phase epitaxy on N-type polysilicon films formed by aluminium induced crystallization of amorphous silicon
- Author
-
Tüzün, Ö., Slaoui, A., Roques, S., Focsa, A., Jomard, F., and Ballutaud, D.
- Published
- 2009
- Full Text
- View/download PDF
136. Coupling of ToF-SIMS and Raman Spectroscopy for the Characterization of the Chemical Species Involved in the Soot Nucleation Process
- Author
-
Jessy Elias, Alessandro Faccinetto, Nicolas Nuns, Claire Pirim, Cristian Focsa, Xavier Mercier, Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 (PC2A), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut des Molécules et de la Matière Condensée de Lille (IMMCL), Centrale Lille Institut (CLIL)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), and Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[CHIM]Chemical Sciences - Abstract
International audience; Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and Raman spectroscopy are used to characterize samples extracted from a laboratory methane diffusion flame at different reaction times along the flame axis in order to gain information on the soot nucleation process. Experimental results from the comparison of these techniques allow the chemical characterization of the gas to soot particles phase transition and the quantification of the hydrogen content of the sampled matter. Before soot formation, no phase separation is observed on the samples, while after soot formation, a phase separation appears with two families of PAHs and a difference in the Raman signal.
- Published
- 2021
137. Revealing the origin of chemical complexity in extraterrestrial matter by combining multiple characterization techniques: HR-L2MS, TOF-SIMS, and micro-Raman spectroscopy: Invited talk
- Author
-
Pirim, Claire, Dumitru, Duca, Slavicinska, Katerina, Ferrari, Brian, Carpentier, Yvain, Vojkovic, Marin, Chazallon, Bertrand, Focsa, Cristian, Bennett, Christopher J., Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Physique Moléculaire aux Interfaces (PMI), Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and University of Central Florida [Orlando] (UCF)
- Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,[PHYS]Physics [physics] ,Astrochemistry -meteorites ,[SDU]Sciences of the Universe [physics] ,Mass spectrometry imaging techniques ,Micro-Raman Spectroscopy ,Laser desorption ionization mass spectrometry ,[PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph] ,Secondary ion mass spectrometry SIMS ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2021
138. Laser ablation in a running hall effect thruster for space propulsion
- Author
-
Balika, L., Focsa, C., Gurlui, S., Pellerin, S., Pellerin, N., Pagnon, D., and Dudeck, M.
- Published
- 2013
- Full Text
- View/download PDF
139. Seminal plasma insemination during ovum-pickup—a method to increase pregnancy rate in IVF/ICSI procedure. A pilot randomized trial
- Author
-
Chicea, Radu, Ispasoiu, Florin, and Focsa, Mircea
- Published
- 2013
- Full Text
- View/download PDF
140. Rare earth doped cobalt ferrite thin films deposited by PLD
- Author
-
Dascalu, Georgiana, Pompilian, Gloria, Chazallon, Bertrand, Nica, Valentin, Caltun, Ovidiu Florin, Gurlui, Silviu, and Focsa, Cristian
- Published
- 2013
- Full Text
- View/download PDF
141. On the Interferometric Capabilities of the Pulson P440 UWB Radar
- Author
-
Focsa, Adrian, primary, Toma, Stefan-Adrian, additional, and Gorgoteanu, Damian, additional
- Published
- 2021
- Full Text
- View/download PDF
142. Multiscale analysis of Jurassic rocks with sulfur-rich organic matter using laser desorption/ionization mass spectrometry
- Author
-
Nicolas Tribovillard, Dmitrii Egorov, Dumitru Duca, Siveen Thlaijeh, Kevin Lepot, Cristian Focsa, Armelle Riboulleau, and Yvain Carpentier
- Subjects
chemistry.chemical_classification ,chemistry ,Laser desorption ionization mass spectrometry ,Analytical chemistry ,chemistry.chemical_element ,Organic matter ,Sulfur - Abstract
The Mars organic molecular analyzer (MOMA) of the Rosalind Franklin rover (ExoMars project) will combine laser desorption-ionization mass spectrometry (LDI-MS) and gas-chromatography mass spectrometry (GC-MS) to assess the origin of organic matter on planet Mars. In order to further assess the type of molecular information that can be retrieved with the former technique, we applied high-resolution laser two-step mass spectrometry (L2MS) to fossil organic matter of sedimentary rock from the Jurassic deposit of Orbagnoux, France. Abundant sulfur-rich microbial organic matter has been thoroughly documented in this deposit [1]. This sample has been chosen following the detection of thiophenes at Gale Crater on Mars by the Sample analysis at Mars (SAM) instrument [2]. In our L2MS instrument [3], the samples are irradiated with a pulsed desorption laser (532 or 266 nm), which generates a plume of chemical species that can be further ionized with a second orthogonal laser beam (266 nm). A radiofrequency ion guide is used to carry the ions to an orthogonal time-of-flight mass spectrometer (oToF-MS system by Fasmatech), yielding high-resolution mass spectra (m/Δm ~10000 at 128 m/z). Focusing of the desorption laser using a reflective objective and automated micro-positioning of the sample were used to generate hyperspectral raster mappings. Subsamples included solvent-extracted molecules (bitumen and maltene fractions), insoluble macromolecular organic matter (kerogen), rock powder and a polished slice. Our analyses showed that we can extract chemical information with LDI-MS from both soluble and insoluble organic fractions of the Orbagnoux samples and that various chemical families can be distinguished even in mineralized samples. Carbon clusters, including sulfurated and hydrogenated species could be detected in all subsamples. With the exception of the rock slice, polyaromatic hydrocarbons could be detected in all samples. Oxygenated molecules and alkylbenzenes could only be detected in extracts, which generated rich and intense mass spectra. Various inorganic ions were also generated in all sample fractions. Using focused desorption beams, carbon clusters (including sulfurated clusters) and inorganic species could be detected and mapped in the polished slice with [1] Mongenot, T., Derenne, S., Largeau, C., Tribovillard, N.P., Lallier-Vergès, E., Dessort, D., Connan, J., 1999. Spectroscopic, kinetic and pyrolytic studies of kerogen from the dark parallel laminae facies of the sulphur-rich Orbagnoux deposit (Upper Kimmeridgian, Jura). Org. Geochem. 30, 39–56. [2] Eigenbrode, J.L., Summons, R.E., Steele, A., Freissinet, C., Millan, M., Navarro-González, R., Sutter, B., McAdam, A.C., Franz, H.B., Glavin, D.P., Archer, P.D., Mahaffy, P.R., Conrad, P.G., Hurowitz, J.A., Grotzinger, J.P., Gupta, S., Ming, D.W., Sumner, D.Y., Szopa, C., Malespin, C., Buch, A., Coll, P., 2018. Organic matter preserved in 3-billion-year-old mudstones at Gale crater, Mars. Science (80-. ). 360, 1096–1101. [3] A. Faccinetto, P. Desgroux, M. Ziskind, E. Therssen, C. Focsa, High-sensitivitydetection of polycyclic aromatic hydrocarbons adsorbed onto soot particles using laser desorption/laser ionization/time-of-flight mass spectrometry: An approach to studying the soot inception process in low-pressure flames, Combustion and Flame 158 (2011) 227–239.
- Published
- 2021
- Full Text
- View/download PDF
143. Sarcoma Molecular Pathological Diagnosis of FFPE Tissues without Dewaxing based on Lipidomic Profiles using SpiderMass Technology
- Author
-
Cristian Focsa, Emmanuel Bouchaert, Yves-Marie Robin, Isabelle Fournier, Michel Salzet, Benoit Fatou, Zoltan Takats, Delphine Bertin, Mickael Ziskind, Dominique Tierny, Pierre-Damien Caux, and Nina Ogrinc
- Subjects
Pathology ,medicine.medical_specialty ,Text mining ,business.industry ,Medicine ,Sarcoma ,business ,medicine.disease ,Pathological - Abstract
Background :Formalin-fixation and paraffin-embedding (FFPE) is the worldwide gold standard for tissue preservation and routine pathology for general and cancer diagnostics. Despite robust histopathology methods, accurate diagnostic remains difficult for certain cases. Overall, the entire process is time-consuming, labor-intensive and doesn’t reach the right sensitivity and specificity. Lipids are central players in cancer, but they are not routinely used in diagnostics because of the sample processing which limits their detection, and lipid analysis directly from unprocessed FFPE tissues has never been reported. Methods :We present a new method for cancer diagnostics based on tissue-lipidomic signatures through rapid screening of FFPE without dewaxing using Water-Assisted Laser Desorption Ionization Mass Spectrometry (WALDI-MS) and deep-learning. Results :We show on a cohort of canine and human sarcoma tissues that classification for sarcoma sub-typing is possible and enables diagnosing blind samples in less than five minutes, with over 95% probability to discriminate specific subtypes. Conclusion: We have revealed the possibility to create a rapid diagnostic platform to screen clinical FFPE tissues with minimal sample preparation for molecular pathology.
- Published
- 2021
- Full Text
- View/download PDF
144. Liquid Combustion Aerosol Standard Generator (CAST): a low-cost alternative combustion emission source for aeronautical fuel evaluation
- Author
-
Rafael Barrellon-Vernay, David Delhaye, Mathieu Cazaunau, Bergé, A., Pangui, E., Berthier, A., Nicolas Karoski, Alexandre Albinet, Jean-Eudes Petit, Singh, A., Ser, F., Jean-Francois Doussin, Cristian Focsa, Ortega, Ismael K., Civs, Gestionnaire, DMPE, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut National de l'Environnement Industriel et des Risques (INERIS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDE] Environmental Sciences ,[SDE]Environmental Sciences - Abstract
International audience; Emissions from aircraft engines impact climate and air quality in and around airports (Airbus GMF 2018, Vorster et al. 2013). There are different options available to reduce aircraft emissions, based notably on the development of sustainable fuels. The evaluation of the physicochemical characteristics of the particulate emissions from such fuels in real conditions is difficult to achieve and very expensive. The mini-CAST burner, suitable for the combustion of liquid fuel (Jing 2003), is an interesting alternative to obtain soot emissions comparable to those from aircraft engine. The design of the liquid CAST is based on the conventional propane model but here, the propane flame is used to vaporize the fuel in the combustion chamber to further generate a flame. A quenching flow of nitrogen stops the combustion reactions and a flow of dilution air accelerates emissions in the measurement line and avoids soot agglomeration. This work aimed to characterize CAST emissions for aircraft fuels of different chemical compositions and to study their stability and reproducibility.
- Published
- 2021
145. RÔLE DE LA RÉACTIVITÉ DES PRODUITS RÉSIDUAIRES ORGANIQUES SUR LA FORMATION D'AÉROSOLS ORGANIQUES SECONDAIRES
- Author
-
R. CIURARU, J. KAMMER, C DECUQ, M. VOJKOVIC, K. HAIDER, Y. CARPENTIER, F. LAFOUGE, C. BERGER, M. BOURDAT-DESCHAMPS, I. K. ORTEGA, F. LEVAVASSEUR, S. HOUOT, B. LOUBET, D. PETITPREZ, and C. FOCSA
- Subjects
ozone ,produits résiduaires organiques ,new particle formation ,organic waste products ,aérosols organiques secondaires ,ozone reactivity ,agricultural secondary organic aerosols - Abstract
Les aérosols organiques secondaires représentent une des principales sources d'incertitudes dans la compréhension actuelle du climat. Il est bien connu maintenant que l'agriculture contribue aux émissions d'aérosols primaires dans l'atmosphère, mais il n'existe pas d'estimation sur la formation d'aérosols organiques secondaires. Ce travail montre que les produits résiduaires organiques, et notamment les boues d'épuration, représentent une source non comptabilisée de précurseurs d'aérosols organiques secondaires par ses émissions de scatole, C9H9N. Les taux d'émission et de nucléation du scatole dus à la réactivité de l'ozone ont été déterminés en laboratoire. Nos résultats montrent que le SO2 joue un rôle clé dans l'oxydation du scatole et entraîne la formation de nouvelles particules. Les résultats présentés ici apportent de nouvelles connaissances sur un nouveau mécanisme de nucléation à partir du recyclage des produits résiduaires organiques., Secondary organic aerosols (SOA) are one of the main uncertainty sources in the current understanding of the Earth's Climate. It is known that agriculture contributes to primary aerosols emissions but there is no estimate for the secondary organic aerosol formation from precursor gas phase. Organic waste products like sewage sludge are applied to cropland as fertilizers. In this work we show that sewage sludge is an unaccounted source of nucleation precursors (skatole, C9H9N). The skatole emission and nucleation rates due to ozone reactivity were determined in the laboratory. Based on our results, SO2 plays a key role in the oxidation of skatole and leads to new particle formation. The results presented here provide new insights into this novel nucleation mechanism and aid our understanding of the organic waste agricultural recycling contribution to the aerosol balance in the atmosphere.
- Published
- 2021
- Full Text
- View/download PDF
146. IMPACT DU CATALYSEUR SUR LES CARACTÉRISTIQUES PHYSICO-CHIMIQUES DES PARTICULES ÉMISES PAR LA COMBUSTION D'UN CARBURANT AÉRONAUTIQUE
- Author
-
A. BERTHIER, R. BARRELLON-VERNAY, I. K. ORTEGA, D. DELHAYE, and C. FOCSA
- Subjects
caractéristiques physico-chimiques ,catalytic stripper ,non-volatile particles ,particules non volatiles ,physico-chemical characteristics ,catalyseur - Abstract
Cette étude vise à mettre en évidence l'impact d'un lit catalytique sur les caractéristiques physico-chimiques des particules émises par combustion d'un carburant aéronautique, c'est-à-dire leur concentration en nombre et en masse, leur distribution en taille ou leur composition chimique. En détruisant les composés organiques présents en phase volatile mais également à la surface des particules non volatiles, le catalyseur a pour effet de réduire la taille des particules ainsi que leur concentration en nombre et en masse. La caractérisation chimique a également montré son rôle dans la destruction des composés soufrés., This study aims to highlight the impact of a catalytic stripper on the physical and chemical characteristics of particles emitted by aeronautic fuel combustion, i.e. their mass and number concentration, size distribution or chemical composition. It has been shown that by destroying the organic compounds present in the volatile phase but also on the surface of non-volatile particles, the catalytic stripper has the effect of reducing the size of the particles as well as their mass and number concentration. Chemical characterization has also shown its role in the destruction of sulfur compounds.
- Published
- 2021
- Full Text
- View/download PDF
147. SUBSTITUT DE MOTEURS D'AVIONS POUR RECHERCHE EN LABORATOIRE
- Author
-
R. BARRELLON-VERNAY, A. BERTHIER, D. DELHAYE, I.K. ORTEGA, F. SER, and C. FOCSA
- Subjects
caractérisation physico-chimique ,physico-chemical characterization ,non-volatile particles ,suies ,particules non volatiles ,émissions de moteurs aéronautiques ,aircraft engine emissions ,soot - Abstract
Les émissions issues des moteurs aéronautiques ont un impact sur le climat et la qualité de l'air, dans et autour des aéroports. Il existe différentes options pour réduire les émissions des aéronefs, basées notamment sur le développement de nouveaux carburants alternatifs. Un brûleur mini-CAST, adapté à la combustion de carburants liquides, est utilisé comme source représentative et reproductible pour la production de suies similaires à celles des émissions des moteurs d'avions. Ce travail vise à caractériser physiquement et chimiquement les émissions du CAST et à étudier sa stabilité afin de pouvoir en faire usage sur des bancs d'essais et lors de futures campagnes nécessitant une source de combustion fiable., Emissions from aircraft engines impact climate and air quality in and around airports. There are different options available to reduce aircraft emissions, based in particular on the development of new sustainable fuels. A mini-CAST burner suitable for the combustion of liquid fuel is used as a representative and a reproducible source in soot production similar to aircraft engine emissions. This work aims for physico-chemical characterization of the CAST and for studying its stability in view of use on test benches.
- Published
- 2021
- Full Text
- View/download PDF
148. Attention networks and the intrinsic network structure of the human brain
- Author
-
Markett, Sebastian, Nothdurfter, David, Focsa, Antonia, Reuter, Martin, Jawinski, Philippe, Markett, Sebastian, Nothdurfter, David, Focsa, Antonia, Reuter, Martin, and Jawinski, Philippe
- Abstract
Attention network theory distinguishes three independent systems, each supported by its own distributed network: an alerting network to deploy attentional resources in anticipation, an orienting network to direct attention to a cued location, and a control network to select relevant information at the expense of concurrently available information. Ample behavioral and neuroimaging evidence supports the dissociation of the three attention domains. The strong assumption that each attentional system is realized through a separable network, however, raises the question how these networks relate to the intrinsic network structure of the brain. Our understanding of brain networks has advanced majorly in the past years due to the increasing focus on brain connectivity. The brain is intrinsically organized into several large-scale networks whose modular structure persists across task states. Existing proposals on how the presumed attention networks relate to intrinsic networks rely mostly on anecdotal and partly contradictory arguments. We addressed this issue by mapping different attention networks at the level of cifti-grayordinates. Resulting group maps were compared to the group-level topology of 23 intrinsic networks, which we reconstructed from the same participants' resting state fMRI data. We found that all attention domains recruited multiple and partly overlapping intrinsic networks and converged in the dorsal fronto-parietal and midcingulo-insular network. While we observed a preference of each attentional domain for its own set of intrinsic networks, implicated networks did not match well to those proposed in the literature. Our results indicate a necessary refinement of the attention network theory., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, We acknowledge support by the Open Access Publication Fund of Humboldt‐Universität zu Berlin., Peer Reviewed
- Published
- 2021
149. Structure of neat and hydrated liquid nicotine and laser resonant desorption of clusters from nicotine–water solutions
- Author
-
Mihesan, Claudia, Ziskind, Michael, Focsa, Cristian, Seydou, Mahamadou, Lecomte, Frédéric, and Schermann, Jean Pierre
- Published
- 2008
- Full Text
- View/download PDF
150. Abstract 3813: Unification of over 50 published single-cell RNA datasets covering over a 1000 patient samples with deep-learning reveals novel axes of tumor microenvironment variation
- Author
-
Javier Díaz-Mejía, Swechha X, Dylan Mendonca, Octavian Focsa, Chris Harvey, Mike Briskin, and Sam Cooper
- Subjects
Cancer Research ,Oncology - Abstract
Background: Due to sizeable batch effect challenges, published scRNA datasets remain siloed, with no tools or packages yet demonstrating an ability to integrate more than a handful of datasets into a unified atlas. This has precluded generation of a large-unified Atlas akin to The Cancer Genome Atlas (TCGA) for scRNA, despite massive demand for such a resource. Methods: We built the first training scRNA dataset that we know of that relies on using cell-type labels from published studies as a ground-truth metric. Using this dataset, we evaluated and trained a variety of models specifically for the task of integrating disparate data into a unified space. Further we developed a specific framework for evaluating how well unsupervised models perform at the task of integrating disparate data, using a new approach reliant on leave-one out validation of ‘unseen’ datasets. Using deep-learning models, that performed best on the training dataset, we scaled integration of over 50 public datasets focused on solid cancers, that collectively contain over 1000 patient samples worth of data covering over 20 indications. Results: The pan-cancer scRNA atlas produced by the above workflow is an order of magnitude larger than previous scRNA datasets and the first to span many indications alongside adjacent and separate normal tissue data. Analysis of this atlas reveals novel axes of variation in the tumor microenvironment linked to Cancer Associated Fibroblast (CAF) biology. For example: (a) We find CAF high samples vs. cancer high samples are enriched for T-cells in a naïve state; (b) Cancer vs. CAF rich samples result in variation in M2 like macrophage signatures; this compartmentalization is also seen in spatial RNA data; (c) A spectrum of CAF, perivascular, and endothelial like states is also observed indicating potential cell-type plasticity. Collectively, these observations identify novel biology and variation in the tumor microenvironment that will likely apply to many ongoing experimental projects and therapeutic programs. Conclusions: We’ve used deep-learning to build one of the largest scRNA atlases to date, and potentially the first that will progressively release models and data as an open-source package to benefit the wider community. We anticipate the ability to resolve target expression at the single cell level will greatly enhance our understanding of the tumor microenvironment, as it aids our own efforts to drug CAF biology and the tumor stroma. Citation Format: Javier Díaz-Mejía, Swechha X, Dylan Mendonca, Octavian Focsa, Chris Harvey, Mike Briskin, Sam Cooper. Unification of over 50 published single-cell RNA datasets covering over a 1000 patient samples with deep-learning reveals novel axes of tumor microenvironment variation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3813.
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.