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1. Membrane-remodeling protein ESCRT-III homologs incarnate the evolution and morphogenesis of multicellular magnetotactic bacteria

Author

Wenyan Zhang, Jianwei Chen, Jie Dai, Shiwei Zhu, Hugo Le Guenno, Artemis Kosta, Hongmiao Pan, Xin-Xin Qian, Claire-Lise Santini, Nicolas Menguy, Xuegong Li, Yiran Chen, Jia Liu, Kaixuan Cui, Yicong Zhao, Guilin Liu, Eric Durand, Wei-Jia Zhang, Alain Roussel, Tian Xiao, Long-Fei Wu, Helmholtz-Zentrum Geesthacht (GKSS), Ming Hsieh Department of Electrical Engineering [Los Angeles], USC Viterbi School of Engineering, University of Southern California (USC)-University of Southern California (USC), Research Center for Proteome Analysis Key Lab of Proteomics, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Chinese Academy of Sciences [Beijing] (CAS), Yale School of Medicine [New Haven, Connecticut] (YSM), Centre d'Immunologie de Marseille - Luminy (CIML), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), CAS Key Laboratory of Marine Ecology and Environmental Science (KLMEES), CAS Institute of Oceanology (IOCAS), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Laboratoire de chimie bactérienne (LCB), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms ( LIA-MagMC), Chinese Academy of Sciences [Beijing] (CAS)-Centre National de la Recherche Scientifique (CNRS), Xi'an Jiaotong University (Xjtu), Endothélium, valvulopathies et insuffisance cardiaque (EnVI), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Architecture et fonction des macromolécules biologiques (AFMB), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)

Subjects
[SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE]
Abstract

Endosomal sorting complex required transport (ESCRT) III proteins are essential for membrane remodeling and repair across all domains of life. Eukaryotic ESCRT-III and the cyanobacterial homologs PspA and Vipp1/Imm30 remodel membrane into vesicles, rings, filaments and tubular rods structures. Here our microscopy analysis showed that multicellular bacteria, referred to as magnetoglobules, possess multiple compartments including magnetosome organelles, polyphosphate granules, vesicles, rings, tubular rods, filaments and MVB-like structures. Therefore, membrane remodeling protein PspA might be required for the formation of these compartments, and contribute to the morphogenesis and evolution of multicellularity. To assess these hypotheses, we sequenced nine genomes of magnetoglobules and found a significant genome expansion compared to unicellular magnetotactic bacteria. Moreover, PspA was ubiquitous in magnetoglobules and formed a distinct clade on the tree of eubacterial and archaeal ESCRT-III. The phylogenetic feature suggested the evolution of magnetoglobules from a unicellular ancestor of deltaproteobacterium. Hetero-expression of ellipsoidal magnetoglobulepspA2gene alone inEscherichia coliresulted in intracellular membrane aggregation. GFP fusion labeling revealed polar location of PspA2 in rod-shaped unicells and regular interval location in filamentous cells. Cryo-electron tomography analysis showed filament bundle, membrane sacculus, vesicles and MVB-like structure in the cells expressing PspA2. Moreover, electron-dense area with a similar distribution as GFP-PspA2 foci in filamentous cells changed the inward orientation of the septum, which might interfere with the cell division. Collectively, these results show the membrane remodeling function of magnetoglobule PspA proteins, which may contribute to morphogenesis and the evolution of multicellularity of magnetotactic bacteria.

Published
2022

2. Quadratically Tight Relations for Randomized Query Complexity

Author

Rahul Jain, Miklos Santha, Jevgēnijs Vihrovs, Srijita Kundu, Hartmut Klauck, Swagato Sanyal, Troy Lee, Ming Hsieh Department of Electrical Engineering [Los Angeles], USC Viterbi School of Engineering, University of Southern California (USC)-University of Southern California (USC), Chennai Mathematical Institute [Inde], Centre National de la Recherche Scientifique (CNRS), Institut de Recherche en Informatique Fondamentale (IRIF (UMR_8243)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre for Quantum Technologies [Singapore] (CQT), and National University of Singapore (NUS)

Subjects
Quadratic growth, [INFO.INFO-CC]Computer Science [cs]/Computational Complexity [cs.CC], 0209 industrial biotechnology, 0102 computer and information sciences, 02 engineering and technology, Measure (mathematics), Upper and lower bounds, 01 natural sciences, ACM: F.: Theory of Computation, Square (algebra), Computation Theory & Mathematics, Theoretical Computer Science, Combinatorics, Quadratic equation, 020901 industrial engineering & automation, Computational Theory and Mathematics, 010201 computation theory & mathematics, Theory of computation, Information complexity, [INFO]Computer Science [cs], 0102 Applied Mathematics, 0802 Computation Theory and Mathematics, 0805 Distributed Computing, Communication complexity, Boolean function, ComputingMilieux_MISCELLANEOUS, Mathematics
Abstract

In this work we investigate the problem of quadratically tightly approximating the randomized query complexity of Boolean functions R(f). The certificate complexity C(f) is such a complexity measure for the zero-error randomized query complexity R0(f): C(f) ≤R0(f) ≤C(f)2. In the first part of the paper we introduce a new complexity measure, expectational certificate complexity EC(f), which is also a quadratically tight bound on R0(f): EC(f) ≤R0(f) = O(EC(f)2). For R(f), we prove that EC2/3 ≤R(f). We then prove that EC(f) ≤C(f) ≤EC(f)2 and show that there is a quadratic separation between the two, thus EC(f) gives a tighter upper bound for R0(f). The measure is also related to the fractional certificate complexity FC(f) as follows: FC(f) ≤EC(f) = O(FC(f)3/2). This also connects to an open question by Aaronson whether FC(f) is a quadratically tight bound for R0(f), as EC(f) is in fact a relaxation of FC(f). In the second part of the work, we investigate whether the corruption bound corr𝜖(f) quadratically approximates R(f). By Yao’s theorem, it is enough to prove that the square of the corruption bound upper bounds the distributed query complexity $\mathsf {D}^{\mu }_{\epsilon }(f)$ for all input distributions μ. Here, we show that this statement holds for input distributions in which the various bits of the input are distributed independently. This is a natural and interesting subclass of distributions, and is also in the spirit of the input distributions studied in communication complexity in which the inputs to the two communicating parties are statistically independent. Our result also improves upon a result of Harsha et al. (2016), who proved a similar weaker statement. We also note that a similar statement in the communication complexity is open.

Published
2020
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4. MABO-TSCH: Multi-hop And Blacklist-based Optimized Time Synchronized Channel Hopping

Author

Gomes, Pedro Henrique, Watteyne, Thomas, Krishnamachari, Bhaskar, Department of Electrical Engineering [Los Angeles], University of Southern California (USC), Wireless Networking for Evolving & Adaptive Applications (EVA), Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), European Project: 687884,H2020 Pilier Industrial Leadership,H2020-ICT-2015,F-Interop(2015), and European Project: 688237,H2020 Pilier Industrial Leadership,H2020-ICT-2015,ARMOUR(2016)

Subjects
[INFO]Computer Science [cs], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

5. Teaching Communication Technologies and Standards for the Industrial IoT? Use 6TiSCH!

Author

Xavier Vilajosana, Thomas Watteyne, Pere Tuset-Peiró, Bhaskar Krishnamachari, Sofie Pollin, Wireless Networking for Evolving & Adaptive Applications (EVA), Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), OpenMote Technologies [Barcelona], Universitat Oberta de Catalunya [Barcelona] (UOC), Departement Elektrotechniek - ESAT [leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Department of Electrical Engineering [Los Angeles], University of Southern California (USC), Inria DIVERSITY associate team, European Project: 687884,H2020 Pilier Industrial Leadership,H2020-ICT-2015,F-Interop(2015), and European Project: 688237,H2020 Pilier Industrial Leadership,H2020-ICT-2015,ARMOUR(2016)

Subjects
RPL, Internet of things, Internet de les coses, Computer Networks and Communications, Computer science, Process (engineering), Access control, 02 engineering and technology, IETF 6TiSCH, computer.software_genre, Asset (computer security), Internet de las cosas, IEEE 802.15.4 TSCH, 0202 electrical engineering, electronic engineering, information engineering, Wireless, [INFO]Computer Science [cs], Electrical and Electronic Engineering, 6LoWPAN, Multimedia, Wireless mesh network, business.industry, 020208 electrical & electronic engineering, 020206 networking & telecommunications, Computer Science Applications, IPv6, CoAP, The Internet, Telecommunications, business, computer
Abstract

International audience; The IETF 6TiSCH stack encompasses IEEE802.15.4 TSCH, IETF 6LoWPAN, RPL, and CoAP. It is one of the key standards-based technologies to enable industrial process monitoring and control, and unleash the Industrial Internet of Things (IIoT). The 6TiSCH stack is also a valuable asset for educational purposes, as it integrates an Internet-enabled IPv6-based upper stack with stateof- the-art low-power wireless mesh communication technologies. Teaching with 6TiSCH empowers students with a valuable set of competencies, including topics related to computer networking (medium access control operation, IPv6 networking), embedded systems (process scheduling, concurrency), and wireless communications (multipath propagation, interference effects), as well as application requirements for the IIoT. This article discusses how the 6TiSCH stack can be incorporated into existing and new curricula to teach the next generation of electrical engineering and computer science professionals about designing and deploying such networks. It also gives a comprehensive overview of the 6TiSCH stack and the tools that exist to support a course based on it.

Published
2017
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6. The WISDOM Radar: Unveiling the Subsurface Beneath the ExoMars Rover and Identifying the Best Locations for Drilling

Author

Valérie Ciarletti, Stephen Clifford, Dirk Plettemeier, Alice Le Gall, Yann Hervé, Sophie Dorizon, Cathy Quantin-Nataf, Wolf-Stefan Benedix, Susanne Schwenzer, Elena Pettinelli, Essam Heggy, Alain Herique, Jean-Jacques Berthelier, Wlodek Kofman, Jorge L. Vago, Svein-Erik Hamran, null the WISDOM Team, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lunar and Planetary Institute [Houston] (LPI), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Nachrichtentechnik [Dresden] (IfN), Centre for Earth, Planetary, Space and Astronomical Research [Milton Keynes] (CEPSAR), The Open University [Milton Keynes] (OU), Dipartimento di Matematica e Fisica [Roma], Università degli Studi Roma Tre, Ming Hsieh Department of Electrical Engineering [Los Angeles], USC Viterbi School of Engineering, University of Southern California (USC)-University of Southern California (USC), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Space Research Centre of Polish Academy of Sciences (CBK), Polska Akademia Nauk = Polish Academy of Sciences (PAN), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Forsvarets Forskningsinstitutt (FFI), IMPEC - LATMOS, Technische Universität Dresden (TUD), Dipartimento di Matematica e Fisica [Rome], Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Polska Akademia Nauk (PAN), Ciarletti, V., Clifford, S., Plettemeier, D., Le Gall, A., Herve, Y., Dorizon, S., Quantin-Nataf, C., Benedix, W. -S., Schwenzer, S., Pettinelli, E., Heggy, E., Herique, A., Berthelier, J. -J., Kofman, W., Vago, J. L., Hamran, S. -E., Ciarletti, Valérie, Clifford, Stephen, Plettemeier, Dirk, Le Gall, Alice, Hervé, Yann, Dorizon, Sophie, Quantin-Nataf, Cathy, Benedix, Wolf-Stefan, Schwenzer, Susanne, Pettinelli, Elena, Heggy, Essam, Herique, Alain, Berthelier, Jean-Jacque, Kofman, Wlodek, Vago, Jorge L., Hamran, Svein-Erik, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi Roma Tre = Roma Tre University (ROMA TRE), and Agence Spatiale Européenne = European Space Agency (ESA)

Subjects
010504 meteorology & atmospheric sciences, Special Collection of Papers: ExoMars Rover MissionGuest Editor: Jorge L. Vago, Life on Mars, 01 natural sciences, Astrobiology, law.invention, Ground penetrating radar, law, 0103 physical sciences, Radar, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Drill, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Drilling, Martian shallow subsurface, Mars Exploration Program, Regolith, Agricultural and Biological Sciences (miscellaneous), ExoMars, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Stratigraphy, 13. Climate action, Space and Planetary Science, Ground-penetrating radar, Geology
Abstract

International audience; The search for evidence of past or present life on Mars is the principal objective of the 2020 ESA-Roscosmos ExoMars Rover mission. If such evidence is to be found anywhere, it will most likely be in the subsurface, where organic molecules are shielded from the destructive effects of ionizing radiation and atmospheric oxidants. For this reason, the ExoMars Rover mission has been optimized to investigate the subsurface to identify, understand, and sample those locations where conditions for the preservation of evidence of past life are most likely to be found. The Water Ice Subsurface Deposit Observation on Mars (WISDOM) ground-penetrating radar has been designed to provide information about the nature of the shallow subsurface over depth ranging from 3 to 10 m (with a vertical resolution of up to 3 cm), depending on the dielectric properties of the regolith. This depth range is critical to understanding the geologic evolution stratigraphy and distribution and state of subsurface H2O, which provide important clues in the search for life and the identification of optimal drilling sites for investigation and sampling by the Rover's 2-m drill. WISDOM will help ensure the safety and success of drilling operations by identification of potential hazards that might interfere with retrieval of subsurface samples. Key Words: Ground penetrating radar—Martian shallow subsurface—ExoMars. Astrobiology 17, 565–584.

Published
2017
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7. Insights into Frequency Diversity from Measurements on an Indoor Low Power Wireless Network Testbed

Author

Thomas Watteyne, Ying Chen, Bhaskar Krishnamachari, Pedro Gomes, Department of Electrical Engineering [Los Angeles], University of Southern California (USC), Nanjing University of Science and Technology (NJUST), Wireless Networking for Evolving & Adaptive Applications (EVA), Inria de Paris, and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)

Subjects
Wi-Fi array, business.industry, Computer science, Wireless network, Reliability (computer networking), ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS, 020208 electrical & electronic engineering, Testbed, 020206 networking & telecommunications, 02 engineering and technology, 0202 electrical engineering, electronic engineering, information engineering, Wireless, [INFO]Computer Science [cs], business, Multipath propagation, Computer network, Diversity scheme, Communication channel
Abstract

International audience; Recent wireless medium access control techniques, such as the Timeslotted Synchronized Channel Hopping (TSCH) and Deterministic & Synchronous Multi-channel Extension (DSME) modes in the IEEE802.15.4-2015 standard, use frequency diversity to cope with external interference and multipath fading. The result is wire-like reliability in a network built from unreliable wireless links. Yet, the impact of using multiple frequencies on the medium access control layer is still not perfectly understood, and virtually all channel hopping solutions use "blind" channel hopping, i.e., hopping over all frequencies equivalently. The goal of this work is to improve our understanding of the behavior of the wireless medium when using multiple frequencies, which will enable the design of more efficient protocols in the future. We collect a large dense connectivity dataset over the USC Tutornet Internet of Things Testbed, with dozens of low-power wireless nodes deployed in an office building. This publicly-available dataset offers complete traces of link quality across frequency, time and space. We analyze the data and extract meaningful and practical insights on the wireless medium when using multiple frequencies.

Published
2016
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8. Separations in Communication Complexity Using Cheat Sheets and Information Complexity

Author

Aleksandrs Belovs, Shalev Ben-David, Troy Lee, Rahul Jain, Miklos Santha, Robin Kothari, Mika Göös, Anurag Anshu, Center for Quantum Technologies (CQT), National University of Singapore (NUS), University of Toronto, Ming Hsieh Department of Electrical Engineering [Los Angeles], USC Viterbi School of Engineering, University of Southern California (USC)-University of Southern California (USC), Institute for Quantum Computing [Waterloo] (IQC), University of Waterloo [Waterloo], Centre National de la Recherche Scientifique (CNRS), Institut de Recherche en Informatique Fondamentale (IRIF (UMR_8243)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre for Quantum Technologies [Singapore] (CQT), and Centrum Wiskunde & Informatica, Amsterdam (CWI), The Netherlands

Subjects
FOS: Computer and information sciences, [INFO.INFO-CC]Computer Science [cs]/Computational Complexity [cs.CC], 0209 industrial biotechnology, Logarithm, Computer science, FOS: Physical sciences, 0102 computer and information sciences, 02 engineering and technology, Computational Complexity (cs.CC), Computer Science::Computational Complexity, 01 natural sciences, 020901 industrial engineering & automation, Quadratic equation, Communication complexity, ComputingMilieux_MISCELLANEOUS, Discrete mathematics, Quantum algorithms, Quantum Physics, Randomized algorithms, Function (mathematics), Exponential function, Randomized algorithm, Computer Science - Computational Complexity, 010201 computation theory & mathematics, Partial function, Quantum algorithm, Quantum Physics (quant-ph)
Abstract

While exponential separations are known between quantum and randomized communication complexity for partial functions (Raz, STOC 1999), the best known separation between these measures for a total function is quadratic, witnessed by the disjointness function. We give the first super-quadratic separation between quantum and randomized communication complexity for a total function, giving an example exhibiting a power 2.5 gap. We further present a 1.5 power separation between exact quantum and randomized communication complexity, improving on the previous ~1.15 separation by Ambainis (STOC 2013). Finally, we present a nearly optimal quadratic separation between randomized communication complexity and the logarithm of the partition number, improving upon the previous best power 1.5 separation due to G\"o\"os, Jayram, Pitassi, and Watson. Our results are the communication analogues of separations in query complexity proved using the recent cheat sheet framework of Aaronson, Ben-David, and Kothari (STOC 2016). Our main technical results are randomized communication and information complexity lower bounds for a family of functions, called lookup functions, that generalize and port the cheat sheet framework to communication complexity., Comment: v1: 36 pages, 1 figure; v2: Added separation between exact quantum and bounded-error randomized communication, 39 pages, 2 figures

Published
2016
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9. Cosmochemical implications of CONSERT permittivity characterization of 67P/CG

Author

Jérémie Lasue, Anny Chantal Levasseur-Regourd, Sonia Zine, Pierre Beck, Wlodek Kofman, Alain Herique, Lydie Bonal, Ilaria Buttarazzi, Essam Heggy, Eric Quirico, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Ming Hsieh Department of Electrical Engineering [Los Angeles], USC Viterbi School of Engineering, University of Southern California (USC)-University of Southern California (USC), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), University of Southern California (USC), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Planeto, Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), IMPEC - LATMOS, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
Permittivity, 67P/Churyumov-Gerasimenko, 010504 meteorology & atmospheric sciences, Comet, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Volatile, Mineralogy, Astrophysics, Dielectric, Radar astronomy, 01 natural sciences, Comet nucleus, 0103 physical sciences, Comets, Porosity, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Refractory, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Depth sounding, 13. Climate action, Space and Planetary Science, Volume fraction, Radio wave
Abstract

International audience; Analysis of the propagation of the CONSERT signal throughout the small lobe of 67P/CG nucleus permitted to deduce the real part of the permittivity, at a value of 1.27± 0.05 [1]. The first interpretation of this value using the dielectric properties of mixtures of ices (H2O, CO2), dusts and porosity, led to the conclusion that the comet porosity ranges between 75 – 85%. In addition, the dust to ice ratio was found to range between 0.4-2.6 and the permittivity of dust (including 30% of porosity) was determined to be lower than 2.9. This last value corresponds to a permittivity lower than 4 for a material without any porosity.This paper is intended to refine the dust permittivity estimate by taking into account the updated values of nucleus densities and dust/ice ratio, and to provide further insights into the nature of the constituents of comet 67P/CG. We adopted a systematic approach: determination of the dust permittivity as a function of the Ice / Dust and Vacuum (i.e. porosity) volume fraction and comparison with the permittivity of meteoritic, mineral and organic material from literature and laboratory measurements. Then different composition models of the nuclei corresponding to cosmochemical endmembers of 67P/CG dust are tested. For each of these models the location in the I/D/V diagram is calculated based on available dielectric measurements, and confronted to the locus of 67P/CG. The number of compliant models is small and the cosmochemical implications of each are discussed to conclude on a preferred model [2]. An important fraction of carbonaceous material is required in the dust in order to match CONSERT permittivity observations, establishing that comets represent a massive carbon reservoir.[1] Kofman et al., Science, 349, 6247, aaa0639, 2015. [2] Herique et al., MNRAS, submitted, 2016.

Published
2016
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10. High-Level Application Development for Sensor Networks: Data-Driven Approach

Author

Animesh Pathak, Viktor K. Prasanna, Software architectures and distributed systems (ARLES), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Department of Electrical Engineering [Los Angeles], University of Southern California (USC), Nikoletseas, Sotiris and Rolim, and José D.P.

Subjects
Focus (computing), business.industry, Computer science, Distributed computing, Real-time computing, 020207 software engineering, 02 engineering and technology, Modular design, computer.software_genre, Data-driven, 020204 information systems, 0202 electrical engineering, electronic engineering, information engineering, Code (cryptography), Compiler, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], business, Representation (mathematics), computer, Implementation, Wireless sensor network
Abstract

International audience; Owing to the large scale of networked sensor systems, ease of program- ming remains a hurdle in their wide acceptance. High-level application development techniques, or macroprogramming provides an easy to use high-level representation to the application developer, who can focus on specifying the behavior of the system, as opposed to the constituent nodes of the wireless sensor network (WSN). This chapter provides an overview of the current approaches to high-level appli- cation design for WSNs, going into the details related to data-driven macroprogram- ming. Details of one such language are provided, in addition to the approach taken to the compilation of data-driven macroprograms to node-level code. An implemen- tation of the modular compilation framework is also discussed, as well as a graphical toolkit built around it that supports data-driven macroprogramming. Through exper- iments, it is shown that the code generated by the compiler matches hand-generated implementations of the applications, while drastically reducing the time and effort involved in developing real-world WSN applications.

Published
2010
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11. Energy-Efficient Task Mapping for Data-Driven Sensor Network Macroprogramming

Author

Animesh Pathak, Viktor K. Prasanna, Software architectures and distributed systems (ARLES), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Department of Electrical Engineering [Los Angeles], and University of Southern California (USC)

Subjects
Speedup, Computer science, Distributed computing, 020206 networking & telecommunications, 02 engineering and technology, Theoretical Computer Science, Data-driven, Computational Theory and Mathematics, Hardware and Architecture, 0202 electrical engineering, electronic engineering, information engineering, Graph (abstract data type), 020201 artificial intelligence & image processing, Routing (electronic design automation), [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], Heuristics, Greedy algorithm, Wireless sensor network, Integer programming, Software, Efficient energy use
Abstract

International audience; Data-driven macroprogramming of wireless sensor networks (WSNs) provides an easy to use high-level task graph representation to the application developer. However, determining an energy-efficient initial placement of these tasks onto the nodes of the target network poses a set of interesting problems. We present a framework to model this task-mapping problem arising in WSN macroprogramming. Our model can capture placement constraints in tasks, as well as multiple possible routes in the target network. Using our framework, we provide mathematical formulations for the task-mapping problem for two different metrics -- energy balance and total energy spent. For both metrics, we address scenarios where a) a single or b) multiple paths are possible between nodes. Due to the complex nature of the problems, these formulations are not linear. We provide linearization heuristics for the same, resulting in mixed-integer programming (MIP) formulations. We also provide efficient heuristics for the above. Our experiments show that our heuristics give the same results as the MIP for real-world sensor network macroprograms, and show a speedup of up to several orders of magnitude. We also provide worst-case performance bounds of the heuristics.

Published
2010
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12. [Invited] ColdFlux Superconducting EDA and TCAD Tools Project: Overview and Progress

Author

Fourie, Coenrad J., Matthys Botha, Pascal Febvre, Christopher Ayala, Qiuyun Xu, Nobuyuki Yoshikawa, Erin Patrick, Mark Law, Yanzhi Wang, Murali Annavaram, Peter Beerel, Sandeep Gupta, Shahin Nazarian, Massoud Pedram, Stellenbosch University (Department of Electrical and Electronics Engineering), Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Yokohama National University (Institute of Advanced Science), University of Florida [Gainesville] (UF), Syracuse University, Ming Hsieh Department of Electrical Engineering [Los Angeles], USC Viterbi School of Engineering, University of Southern California (USC)-University of Southern California (USC), and University of Southern California (USC)

Subjects
[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics
Abstract

4EOr2B-02; International audience

13. High-resolution phase-contrast imaging of biological specimens using a stable betatron X-ray source in the multiple-exposure mode.

Author

Guo B, Zhang X, Zhang J, Hua J, Pai CH, Zhang C, Chu HH, Mori W, Joshi C, Wang J, and Lu W

Abstract

Phase-contrast imaging using X-ray sources with high spatial coherence is an emerging tool in biology and material science. Much of this research is being done using large synchrotron facilities or relatively low-flux microfocus X-ray tubes. An alternative high-flux, ultra-short and high-spatial-coherence table-top X-ray source based on betatron motions of electrons in laser wakefield accelerators has the promise to produce high quality images. In previous phase-contrast imaging studies with betatron sources, single-exposure images with a spatial resolution of 6-70 μm were reported by using large-scale laser systems (60-200 TW). Furthermore, images obtained with multiple exposures tended to have a reduced contrast and resolution due to the shot-to-shot fluctuations. In this article, we demonstrate that a highly stable multiple-exposure betatron source, with an effective average source size of 5 μm, photon number and pointing jitters of <5% and spectral fluctuation of <10%, can be obtained by utilizing ionization injection in pure nitrogen plasma using a 30-40 TW laser. Using this source, high quality phase-contrast images of biological specimens with a 5-μm resolution are obtained for the first time. This work shows a way for the application of high resolution phase-contrast imaging with stable betatron sources using modest power, high repetition-rate lasers.

Published
2019
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14. Role of Direct Laser Acceleration of Electrons in a Laser Wakefield Accelerator with Ionization Injection.

Author

Shaw JL, Lemos N, Amorim LD, Vafaei-Najafabadi N, Marsh KA, Tsung FS, Mori WB, and Joshi C

Abstract

We show the first experimental demonstration that electrons being accelerated in a laser wakefield accelerator operating in the forced or blowout regimes gain significant energy from both the direct laser acceleration (DLA) and the laser wakefield acceleration mechanisms. Supporting full-scale 3D particle-in-cell simulations elucidate the role of the DLA of electrons in a laser wakefield accelerator when ionization injection of electrons is employed. An explanation is given for how electrons can maintain the DLA resonance condition in a laser wakefield accelerator despite the evolving properties of both the drive laser and the electrons. The produced electron beams exhibit characteristic features that are indicative of DLA as an additional acceleration mechanism.

Published
2017
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15. Clustering drug-drug interaction networks with energy model layouts: community analysis and drug repurposing.

Author

Udrescu L, Sbârcea L, Topîrceanu A, Iovanovici A, Kurunczi L, Bogdan P, and Udrescu M

Subjects
Algorithms, Cluster Analysis, Databases, Factual, Drug Interactions, Drug Repositioning, Humans, Precision Medicine, Computational Biology methods
Abstract

Analyzing drug-drug interactions may unravel previously unknown drug action patterns, leading to the development of new drug discovery tools. We present a new approach to analyzing drug-drug interaction networks, based on clustering and topological community detection techniques that are specific to complex network science. Our methodology uncovers functional drug categories along with the intricate relationships between them. Using modularity-based and energy-model layout community detection algorithms, we link the network clusters to 9 relevant pharmacological properties. Out of the 1141 drugs from the DrugBank 4.1 database, our extensive literature survey and cross-checking with other databases such as Drugs.com, RxList, and DrugBank 4.3 confirm the predicted properties for 85% of the drugs. As such, we argue that network analysis offers a high-level grasp on a wide area of pharmacological aspects, indicating possible unaccounted interactions and missing pharmacological properties that can lead to drug repositioning for the 15% drugs which seem to be inconsistent with the predicted property. Also, by using network centralities, we can rank drugs according to their interaction potential for both simple and complex multi-pathology therapies. Moreover, our clustering approach can be extended for applications such as analyzing drug-target interactions or phenotyping patients in personalized medicine applications.

Published
2016
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16. Structured learning algorithm for detection of nonobstructive and obstructive coronary plaque lesions from computed tomography angiography.

Author

Kang D, Dey D, Slomka PJ, Arsanjani R, Nakazato R, Ko H, Berman DS, Li D, and Kuo CC

Abstract

Visual identification of coronary arterial lesion from three-dimensional coronary computed tomography angiography (CTA) remains challenging. We aimed to develop a robust automated algorithm for computer detection of coronary artery lesions by machine learning techniques. A structured learning technique is proposed to detect all coronary arterial lesions with stenosis [Formula: see text]. Our algorithm consists of two stages: (1) two independent base decisions indicating the existence of lesions in each arterial segment and (b) the final decision made by combining the base decisions. One of the base decisions is the support vector machine (SVM) based learning algorithm, which divides each artery into small volume patches and integrates several quantitative geometric and shape features for arterial lesions in each small volume patch by SVM algorithm. The other base decision is the formula-based analytic method. The final decision in the first stage applies SVM-based decision fusion to combine the two base decisions in the second stage. The proposed algorithm was applied to 42 CTA patient datasets, acquired with dual-source CT, where 21 datasets had 45 lesions with stenosis [Formula: see text]. Visual identification of lesions with stenosis [Formula: see text] by three expert readers, using consensus reading, was considered as a reference standard. Our method performed with high sensitivity (93%), specificity (95%), and accuracy (94%), with receiver operator characteristic area under the curve of 0.94. The proposed algorithm shows promising results in the automated detection of obstructive and nonobstructive lesions from CTA.

Published
2015
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17. The development of the Athens Emotional States Inventory (AESI): collection, validation and automatic processing of emotionally loaded sentences.

Author

Chaspari T, Soldatos C, and Maragos P

Subjects
Adult, Data Collection methods, Greece, Humans, Young Adult, Databases, Factual, Emotions physiology, Language, Natural Language Processing
Abstract

Objectives: The development of ecologically valid procedures for collecting reliable and unbiased emotional data towards computer interfaces with social and affective intelligence targeting patients with mental disorders., Methods: Following its development, presented with, the Athens Emotional States Inventory (AESI) proposes the design, recording and validation of an audiovisual database for five emotional states: anger, fear, joy, sadness and neutral. The items of the AESI consist of sentences each having content indicative of the corresponding emotion. Emotional content was assessed through a survey of 40 young participants with a questionnaire following the Latin square design. The emotional sentences that were correctly identified by 85% of the participants were recorded in a soundproof room with microphones and cameras. A preliminary validation of AESI is performed through automatic emotion recognition experiments from speech., Results: The resulting database contains 696 recorded utterances in Greek language by 20 native speakers and has a total duration of approximately 28 min. Speech classification results yield accuracy up to 75.15% for automatically recognizing the emotions in AESI., Conclusions: These results indicate the usefulness of our approach for collecting emotional data with reliable content, balanced across classes and with reduced environmental variability.

Published
2015
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18. Optical imaging for brain tissue characterization using relative fluorescence lifetime imaging.

Author

Papour A, Taylor Z, Sherman A, Sanchez D, Lucey G, Liau L, Stafsudd O, Yong W, and Grundfest W

Subjects
Algorithms, Brain Neoplasms diagnosis, Calibration, Equipment Design, Glioma diagnosis, Humans, Image Processing, Computer-Assisted, Light, Specimen Handling, Tomography, Optical Coherence, Brain pathology, Brain Neoplasms pathology, Glioma pathology, Microscopy, Fluorescence methods, Microscopy, Video instrumentation, Microscopy, Video methods
Abstract

An autofluorescence lifetime wide-field imaging system that can generate contrast in underlying tissue structures of normal and malignant brain tissue samples with video rate acquisition and processing time is presented. Images of the investigated tissues were acquired with high resolution (∼35 μm) using an algorithm to produce contrast based on differences in relative lifetimes. Sufficient contrast for delineation was produced without the computation of fluorescence decay times or Laguerre coefficients. The imaged tissues were sent for histological analysis that confirmed the detected imaged tissues morphological findings and correlations between relative lifetime maps and histology identified.

Published
2013
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19. Intracranial contrast-enhanced magnetic resonance venography with 6.4-fold sensitivity encoding at 1.5 and 3.0 Tesla.

Author

Hu HH, Haider CR, Campeau NG, Huston J 3rd, and Riederer SJ

Subjects
Adult, Artifacts, Female, Humans, Imaging, Three-Dimensional, Male, Middle Aged, Phlebography, Sensitivity and Specificity, Brain blood supply, Magnetic Resonance Imaging methods, Veins anatomy & histology
Abstract

Purpose: To prospectively compare vessel conspicuity and diagnostic image quality between three-dimensional intracranial contrast-enhanced MR venography acquired at 1.5 Tesla (T) and 3.0T, with 6.4-fold sensitivity encoding., Materials and Methods: Ten healthy volunteers were imaged on 1.5T and 3.0T MR scanners using eight-element head coil arrays. The intracranial venous vasculature was divided into five groups for evaluation based on vessel size and anatomical location. Two radiologists independently assessed vessel conspicuity, level of artifacts, and diagnostic image quality. Informed consent was obtained, and the study was approved by the institutional review board., Results: With the exception of large cerebral sinuses where 1.5T and 3.0T results were rated as equivalent, 3.0T images demonstrated superior vessel continuity, sharpness, and signal contrast to background tissue than 1.5T for all other intracranial venous vasculature (P < 0.01). No statistical significance in overall image quality was found between 1.5T and 3.0T venograms, and all data sets were deemed sufficient for diagnostic interpretation., Conclusion: Whole brain contrast-enhanced venography with 6.4-fold sensitivity encoding is robust and has the potential to become the method of choice for fast visualization of the intracranial venous vasculature. At 3.0T, demonstration of small cerebral vessels is superior to 1.5T.

Published
2008
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20. Hybrid optical-digital signal processing applied to an optimal nonlinear phase estimator.

Author

Stephens WE and Steier WH

Abstract

An electrooptical realization of an optimal phase estimator for phase modulated communication signals is described in this work. The realization uses an electrooptical processor to perform a 1-D convolution in a 2-D space and a computer to complete the calculations. The processor is a realization of the time domain recursive nonlinear filter. This paper describes the nonlinear filter theory, the electrooptical realization,and the performance of the processor.

Published
1983
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