133 results on '"Vazan, A."'
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2. Magnesium oxide-water compounds at megabar pressure and implications on planetary interiors
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Shuning Pan, Tianheng Huang, Allona Vazan, Zhixin Liang, Cong Liu, Junjie Wang, Chris J. Pickard, Hui-Tian Wang, Dingyu Xing, and Jian Sun
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Multidisciplinary ,General Physics and Astronomy ,General Chemistry ,General Biochemistry, Genetics and Molecular Biology - Abstract
Magnesium Oxide (MgO) and water (H2O) are abundant in the interior of planets. Their properties, and in particular their interaction, significantly affect the planet interior structure and thermal evolution. Here, using crystal structure predictions and ab initio molecular dynamics simulations, we find that MgO and H2O can react again at ultrahigh pressure, although Mg(OH)2 decomposes at low pressure. The reemergent MgO-H2O compounds are: Mg2O3H2 above 400 GPa, MgO3H4 above 600 GPa, and MgO4H6 in the pressure range of 270–600 GPa. Importantly, MgO4H6 contains 57.3 wt % of water, which is a much higher water content than any reported hydrous mineral. Our results suggest that a substantial amount of water can be stored in MgO rock in the deep interiors of Earth to Neptune mass planets. Based on molecular dynamics simulations we show that these three compounds exhibit superionic behavior at the pressure-temperature conditions as in the interiors of Uranus and Neptune. Moreover, the water-rich compound MgO4H6 could be stable inside the early Earth and therefore may serve as a possible early Earth water reservoir. Our findings, in the poorly explored megabar pressure regime, provide constraints for interior and evolution models of wet planets in our solar system and beyond.
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- 2023
3. اصول علم داده
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Vazan, Milad
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- 2023
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4. From science questions to Solar System exploration
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Dehant, Véronique, Blanc, Michel, Mackwell, Steve, Soderlund, Krista M., Beck, Pierre, Bunce, Emma, Charnoz, Sébastien, Foing, Bernard, Filice, Valerio, Fletcher, Leigh N., Forget, François, Griton, Léa, Hammel, Heidi, Höning, Dennis, Imamura, Takeshi, Jackman, Caitriona, Kaspi, Yohai, Korablev, Oleg, Leconte, Jérémy, Lellouch, Emmanuel, Marty, Bernard, Mangold, Nicolas, Michel, Patrick, Morbidelli, Alessandro, Mousis, Olivier, Prieto-Ballesteros, Olga, Spohn, Tilman, Schmidt, Juergen, Sterken, Veerle J., Tosi, Nicola, Vandaele, Ann C., Vernazza, Pierre, Vazan, Allona, Westall, Frances, Blanc, Michel, Geology and Geochemistry, and Earth Sciences
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Medium ,Asteroid ,Planets ,Small bodies ,Solar System - Abstract
This chapter reviews the way the six key questions about planetary systems, from their origins to the way they work and their habitability, identified in Chapter 1 (Blanc et al., 2021), can be addressed by means of solar system exploration, and how one can find partial answers to these six questions by flying to the different provinces to the solar system: terrestrial planets, giant planets, small bodies, and up to its interface with the local interstellar medium. It derives from this analysis a synthetic description of the most important space observations to be performed at the different solar system objects by future planetary exploration missions. These “observation requirements” illustrate the diversity of measurement techniques to be used as well as the diversity of destinations where these observations must be made. They constitute the base for the identification of the future planetary missions we need to fly by 2061, which are described in Chapter 4.
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- 2023
5. An Equation of State of CO for use in Planetary Modeling
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M. Podolak, A. Levi, A. Vazan, and U. Malamud
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Earth and Planetary Astrophysics (astro-ph.EP) ,Space and Planetary Science ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Although carbon monoxide (CO) is an abundant molecule and may have great importance for planetary interiors, measurements of its properties are difficult due to its extreme volatility. We calculate the equation of state for CO over a range of temperature and density that is applicable to the conditions in planetary interiors. Previous experimental and theoretical studies cover only a limited temperature-density range. Our calculations match these early results well, but now cover the full range of relevance. The method of calculation is based on the general-purpose quotidian equation of state described by More et al. (1988), which is here used in order to generate a freely downloadable look-up table to be used by the community., Comment: 12 pages, 5 figures. Accepted for publication in Icarus
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- 2023
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6. Contributors
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Jorge Alves, Eleonora Ammannito, Nicolas André, Gabriella Arrigo, Sami Asmar, David Atkinson, Adriano Autino, Pierre Beck, Gilles Berger, Michel Blanc, Scott Bolton, Anne Bourdon, Pierre Bousquet, Emma Bunce, Maria Teresa Capria, Pascal Chabert, Sébastien Charnoz, Baptiste Chide, Steve Chien, Ilaria Cinelli, John Day, Véronique Dehant, Brice Demory, Shawn Domagal-Goldman, Caroline Dorn, Alberto G. Fairén, Valerio Filice, Leigh N. Fletcher, Bernard Foing, François Forget, Anthony Freeman, B. Scott Gaudi, Antonio Genova, Manuel Grande, James Green, Léa Griton, Linli Guo, Heidi Hammel, Christiane Heinicke, Ravit Helled, Kevin Heng, Alain Herique, Dennis Höning, Joshua Vander Hook, Aurore Hutzler, Takeshi Imamura, Caitriona Jackman, Yohai Kaspi, Jyeong Ja Kim, Daniel Kitzman, Wlodek Kofman, Eiichiro Kokubo, Oleg Korablev, Jérémie Lasue, Joseph Lazio, Jérémy Leconte, Emmanuel Lellouch, Louis Le Sergeant d'Hendecourt, Jonathan Lewis, Ming Li, Steve Mackwell, Mohammad Madi, Advenit Makaya, Nicolas Mangold, Bernard Marty, Sylvestre Maurice, Ralph McNutt, Patrick Michel, Alessandro Morbidelli, Christoph Mordasini, Olivier Mousis, David Nesvorny, Lena Noack, Masami Onoda, Merav Opher, Gian Gabriele Ori, James Owen, Chris Paranicas, Victor Parro, Maria Antonietta Perino, Christina Plainaki, Robert Preston, Olga Prieto-Ballesteros, Liping Qin, Sascha Quanz, Heike Rauer, Jose A. Rodriguez-Manfredi, Juergen Schmidt, Dave Senske, Ignas Snellen, Krista M. Soderlund, Christophe Sotin, Linda Spilker, Tilman Spohn, Keith Stephenson, Veerle J. Sterken, Leonardo Testi, Nicola Tosi, Yoshio Toukaku, Stéphane Udry, Ann C. Vandaele, Allona Vazan, Julia Venturini, Pierre Vernazza, J. Hunter Waite, Joachim Wambsganss, Armin Wedler, Frances Westall, Philippe Zarka, Sonia Zine, and Qiugang Zong
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- 2023
7. The Relation of Patient Expectations, Satisfaction, and Outcome in Surgery of the Cervical Spine
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Philipp, Krauss, Feline, Reinartz, Clara, Sonnleitner, Martin, Vazan, Florian, Ringel, Bernhard, Meyer, and Hanno S, Meyer
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Motivation ,Treatment Outcome ,Patient Satisfaction ,Cervical Vertebrae ,Humans ,Pain ,Orthopedics and Sports Medicine ,Personal Satisfaction ,Prospective Studies ,Neurology (clinical) - Abstract
We performed a prospective nonblinded single center observational study.To investigate the relationship between expectations, outcome, and satisfaction with the outcome in patients undergoing cervical spine stabilization surgery.In modern healthcare, patient-reported outcome measures and patient satisfaction have become an important aspect of quality control. Therefore, outcome benchmarks for specific diseases are highly desired. Numerous studies have investigated patient-reported outcome measures and what constitutes satisfaction in degenerative lumbar spine disease. In cervical spine surgery, it is less clear what drives the postoperative symptom burden and patient satisfaction and how this depends on the primary diagnosis and other patient factors.This was a prospective, single center, observational study on patients undergoing cervical spine stabilization surgery for degenerative disease, trauma, infection, or tumor. Using the visual analogue scale for neck and arm pain, the neck disability index (NDI), the modified Japanese Orthopedic Association Score (mJOA) and patient-reported satisfaction, patient status and expectations before surgery, at discharge, 6 and 12 months after surgery were evaluated.One hundred five patients were included. Score-based outcome correlated well with satisfaction at 6 and 12 months. Except for low NDI expectations (≥15 points) that correlated with dissatisfaction, expectations in no other score were correlated with satisfaction. Expectations did influence the outcome in some subgroups and meeting expectations resulted in higher rates of satisfaction. Pain reduction plays an important role for satisfaction, independently from the predominant symptom or pathology.Satisfaction correlates well with outcome. Meeting expectations did influence satisfaction with the outcome. The NDI seems to be a valuable preoperative screening tool for poor satisfaction at 12 months. In degenerative pathology, pain is the predominant variable influencing satisfaction independently from the predominant symptom (including myelopathy).5.
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- 2022
8. Developing the World's Brightest WUXGA OLED Microdisplay
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Amal Ghosh, Ilyas Khayrullin, Fridrich Vazan, Fangchao Zhao, Howard Lin, Olivier Prache, Laurie Sziklas, Sri Peruvemba, and Andrew Sculley
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Hardware and Architecture ,Electrical and Electronic Engineering - Published
- 2022
9. Influence of Agronomic Practices on the Persistence of Weed Seedbanks
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Clarence Swanton and Saeed Vazan
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- 2022
10. Implementation of Heterogeneous Multirobotic Cell Control Using Visualization Techniques
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Martin Juhas, Bohuslava Juhasova, and Pavel Vazan
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- 2022
11. Interior and Evolution of the Giant Planets
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Yamila Miguel and Allona Vazan
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Earth and Planetary Astrophysics (astro-ph.EP) ,Astrophysics - Solar and Stellar Astrophysics ,FOS: Physical sciences ,General Earth and Planetary Sciences ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The giant planets were the first to form and hold the key to unveiling the solar system's formation history in their interiors and atmospheres. Furthermore, the unique conditions present in the interiors of the giant planets make them natural laboratories for exploring different elements under extreme conditions. We are at a unique time to study these planets. The missions Juno to Jupiter and Cassini to Saturn have provided invaluable information to reveal their interiors like never before, including extremely accurate gravity data, atmospheric abundances and magnetic field measurements that revolutionised our knowledge of their interior structures. At the same time, new laboratory experiments and modelling efforts also improved, and statistical analysis of these planets is now possible to explore all the different conditions that shape their interiors. We review the interior structure of Jupiter, Saturn, Uranus and Neptune, including the need for inhomogeneous structures to explain the data, the problems unsolved and the effect that advances in our understanding of their internal structure have on their formation and evolution., Review paper published in the special issue "Remote Sensing Observations of the Giant Planets"
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- 2023
12. Chapter 3 - From science questions to Solar System exploration
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Dehant, V, Blanc, M., Mackwell, Steve, Soderlund, K., Beck, Pierre, Bunce, E., Charnoz, S., Foing, B, Filice, Valerio, Flechter, Leigh, Forget, Francois, Griton, L., Hammel, H.B., Höning, Dennis, Imamura, Takeshi, Jackman, Caitriona, Kaspi, Yohai, Korablev, Oleg, Leconte, Jeremy, Lellouch, E., Marty, B., Mangold, Nicolas, Michel, Patrick, Morbidelli, A., Mousis, Olivier, Prieto-Ballesteros, O., Spohn, Tilman, Schmidt, J., Sterken, Veerle, Tosi, Nicola, Vandaele, A.C., Vernazza, Pierre, Vazan, Allona, and Westall, Frances
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Planetary Exploration ,Solar System - Published
- 2022
13. فصل دوم هوش مصنوعی: عاملهای هوشمند
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Vazan, Milad
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- 2022
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14. هوش مصنوعی: حل مسئله با جستجو
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Vazan, Milad
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- 2022
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15. From science questions to Solar System exploration, Chapter 3, Planetary Exploration Horizon 2061 - A Long-Term Perspective for Planetary Exploration
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Dehant V., Blanc M., Mackwell S., Soderlund K.M., Beck P., Bunce E., Charnoz S., Foing B., Filice V., Fletcher L.N., Forget F., Griton L., Hammel H., Höning D., Imamura T., Jackman C., Kaspi Y., Korablev O., Leconte J., Lellouch E., Marty B., Mangold N., Michel P., Morbidelli A., Mousis O., Prieto-Ballesteros O., Spohn T., Schmidt J., Sterken V.J., Tosi N., Vandaele A.C., Vernazza P., Vazan A., W
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- 2022
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16. Planet Formation Theory in the Era of ALMA and Kepler: from Pebbles to Exoplanets
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Drazkowska, Joanna, Bitsch, Bertram, Lambrechts, Michiel, Mulders, Gijs D., Harsono, Daniel, Vazan, Allona, Liu, Beibei, Ormel, Chris W., Kretke, Katherine, and Morbidelli, Alessandro
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Earth and Planetary Astrophysics (astro-ph.EP) ,Astrophysics - Solar and Stellar Astrophysics ,FOS: Physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Our understanding of planet formation has been rapidly evolving in recent years. The classical planet formation theory, developed when the only known planetary system was our own Solar System, has been revised to account for the observed diversity of the exoplanetary systems. At the same time, the increasing observational capabilities of the young stars and their surrounding disks bring new constraints on the planet formation process. In this chapter, we summarize the new information derived from the exoplanets population and the circumstellar disks observations. We present the new developments in planet formation theory, from dust evolution to the growth of planetary cores by accretion of planetesimals, pebbles, and gas. We review the state-of-the-art models for the formation of diverse planetary systems, including the population synthesis approach which is necessary to compare theoretical model outcomes to the exoplanet population. We emphasize that the planet formation process may not be spatially uniform in the disk and there are preferential locations for the formation of planetesimals and planets. Outside of these locations, a significant fraction of solids is not growing past the pebble-sizes. The reservoir of pebbles plays an important role in the growth of planetary cores in the pebble accretion process. The timescale of the emergence of massive planetary cores is an important aspect of the present models and it is likely that the cores within one disk form at different times. In addition, there is growing evidence that the first planetary cores start forming early, during the circumstellar disk buildup process., Comment: 38 pages, 13 figures, review chapter accepted to Protostars and Planets VII, editors: Shu-ichiro Inutsuka, Yuri Aikawa, Takayuki Muto, Kengo Tomida, and Motohide Tamura, corrected label in Fig. 1
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- 2022
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17. Deep Learning: From Basics to Building Deep Neural Networks with Python
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Vazan, Milad
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FOS: Computer and information sciences ,Computer Science - Machine Learning ,ComputingMilieux_COMPUTERSANDEDUCATION ,Machine Learning (cs.LG) - Abstract
This book is intended for beginners who have no familiarity with deep learning. Our only expectation from readers is that they already have the basic programming skills in Python., Comment: 205 pages, in Farsi
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- 2022
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18. Machine Learning and Data Science: Foundations, Concepts, Algorithms, and Tools
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Vazan, Milad
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FOS: Computer and information sciences ,Computer Science - Machine Learning ,Machine Learning (cs.LG) - Abstract
Today, data is a fuel for businesses to gain important insights and improve their performance. There is no industry in the world today that does not use data. But who will get this insight? Who processes all the raw data? Everything is done by a data analyst or a data scientist., Comment: in Persian language
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- 2022
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19. The vulnerability of securing IoT production lines and their network components in the Industry 4.0 concept
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Pavol Tanuska, Zuzana Cervenanska, Jan Janosik, Pavel Vazan, Ladislav Huraj, and Tibor Horak
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0209 industrial biotechnology ,Industry 4.0 ,Computer science ,Wireless network ,business.industry ,Network packet ,020208 electrical & electronic engineering ,Denial-of-service attack ,02 engineering and technology ,Computer security ,computer.software_genre ,Networking hardware ,020901 industrial engineering & automation ,Control and Systems Engineering ,0202 electrical engineering, electronic engineering, information engineering ,The Internet ,business ,computer ,Vulnerability (computing) ,Anonymity - Abstract
IoT systems are an integral part of every modern industrial enterprise Industry 4.0. IoT is the term for modern remote devices controlled via the Internet. Internet of Things is the name of technologies that allow cheap wireless connection and communication of various sensors and devices to automate, accelerate and streamline processes. In the interconnected world of Industry 4.0, there are many potential resources existing for infiltration. Cybercriminals could take control of manufacturing industries, manipulate machines, or could do an industrial espionage. This type of attack is called Denial of Service. In the second case, the attack preserves the attacker’s anonymity through an IP address by using a potentially innocent third party (a reflector) that is indirectly involved in the attack. Through this attack, the attacker forwards the flow of attacking data to the target victim. The attacker sends the packets with a fake spoof source IP address set to the victim’s IP address to the reflector, thus indirectly overloading the target with the packets, or it will intrude into a network device through a faulty WPS implementation. The simulation model of the production line and the IoT security system Fibaro were used to investigate these attacks. The article demonstrates the possibility of attacks on network devices and the misuse of IoT devices in order to compromise production machines which use DRDoS and Brute-force attacks.
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- 2020
20. Ariel: Enabling planetary science across light-years
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Giovanna Tinetti, Paul Eccleston, Carole Haswell, Pierre-Olivier Lagage, Jérémy Leconte, Theresa Lüftinger, Giusi Micela, Michel Min, Göran Pilbratt, Ludovic Puig, Mark Swain, Leonardo Testi, Diego Turrini, Bart Vandenbussche, Maria Rosa Zapatero Osorio, Anna Aret, Jean-Philippe Beaulieu, Buchhave, Lars A., Martin Ferus, Matt Griffin, Manuel Guedel, Paul Hartogh, Pedro Machado, Giuseppe Malaguti, Enric Pallé, Mirek Rataj, Tom Ray, Ignasi Ribas, Robert Szabó, Jonathan Tan, Stephanie Werner, Francesco Ratti, Carsten Scharmberg, Jean-Christophe Salvignol, Nathalie Boudin, Jean-Philippe Halain, Martin Haag, Pierre-Elie Crouzet, Ralf Kohley, Kate Symonds, Florian Renk, Andrew Caldwell, Manuel Abreu, Gustavo Alonso, Jerome Amiaux, Michel Berthé, Georgia Bishop, Neil Bowles, Manuel Carmona, Deirdre Coffey, Josep Colomé, Martin Crook, Lucile Désjonqueres, Díaz, José J., Rachel Drummond, Mauro Focardi, Gómez, Jose M., Warren Holmes, Matthijs Krijger, Zsolt Kovacs, Tom Hunt, Richardo Machado, Gianluca Morgante, Marc Ollivier, Roland Ottensamer, Emanuele Pace, Teresa Pagano, Enzo Pascale, Chris Pearson, Søren Møller Pedersen, Moshe Pniel, Stéphane Roose, Giorgio Savini, Richard Stamper, Peter Szirovicza, Janos Szoke, Ian Tosh, Francesc Vilardell, Joanna Barstow, Luca Borsato, Sarah Casewell, Quentin Changeat, Benjamin Charnay, Svatopluk Civiš, Vincent Coudé du Foresto, Athena Coustenis, Nicolas Cowan, Camilla Danielski, Olivier Demangeon, Pierre Drossart, Edwards, Billy N., Gabriella Gilli, Therese Encrenaz, Csaba Kiss, Anastasia Kokori, Masahiro Ikoma, Juan Carlos Morales, Joao Mendonca, Andrea Moneti, Lorenzo Mugnai, Antonio García Muñoz, Ravit Helled, Mihkel Kama, Yamila Miguel, Nikos Nikolaou, Isabella Pagano, Olja Panic, Miriam Rengel, Hans Rickman, Marco Rocchetto, Subhajit Sarkar, Franck Selsis, Jonathan Tennyson, Angelos Tsiaras, Olivia Venot, Krisztián Vida, Waldmann, Ingo P., Sergey Yurchenko, Gyula Szabó, Rob Zellem, Ahmed Al-Refaie, Javier Perez Alvarez, Lara Anisman, Axel Arhancet, Jaume Ateca, Robin Baeyens, Barnes, John R., Taylor Bell, Serena Benatti, Katia Biazzo, Maria Błęcka, Aldo Stefano Bonomo, José Bosch, Diego Bossini, Jeremy Bourgalais, Daniele Brienza, Anna Brucalassi, Giovanni Bruno, Hamish Caines, Simon Calcutt, Tiago Campante, Rodolfo Canestrari, Nick Cann, Giada Casali, Albert Casas, Giuseppe Cassone, Christophe Cara, Ludmila Carone, Nathalie Carrasco, Paolo Chioetto, Fausto Cortecchia, Markus Czupalla, Chubb, Katy L., Angela Ciaravella, Antonio Claret, Riccardo Claudi, Claudio Codella, Maya Garcia Comas, Gianluca Cracchiolo, Patricio Cubillos, Vania Da Peppo, Leen Decin, Clemence Dejabrun, Elisa Delgado-Mena, Anna Di Giorgio, Emiliano Diolaiti, Caroline Dorn, Vanessa Doublier, Eric Doumayrou, Georgina Dransfield, Luc Dumaye, Emma Dunford, Antonio Jimenez Escobar, Vincent Van Eylen, Maria Farina, Davide Fedele, Alejandro Fernández, Benjamin Fleury, Sergio Fonte, Jean Fontignie, Luca Fossati, Bernd Funke, Camille Galy, Zoltán Garai, Andrés García, Alberto García-Rigo, Antonio Garufi, Giuseppe Germano Sacco, Paolo Giacobbe, Alejandro Gómez, Arturo Gonzalez, Francisco Gonzalez-Galindo, Davide Grassi, Caitlin Griffith, Mario Giuseppe Guarcello, Audrey Goujon, Amélie Gressier, Aleksandra Grzegorczyk, Tristan Guillot, Gloria Guilluy, Peter Hargrave, Marie-Laure Hellin, Enrique Herrero, Matt Hills, Benoit Horeau, Yuichi Ito, Niels Christian Jessen, Petr Kabath, Szilárd Kálmán, Yui Kawashima, Tadahiro Kimura, Antonín Knížek, Laura Kreidberg, Ronald Kruid, Kruijssen, Diederik J. M., Petr Kubelík, Luisa Lara, Sebastien Lebonnois, David Lee, Maxence Lefevre, Tim Lichtenberg, Daniele Locci, Matteo Lombini, Alejandro Sanchez Lopez, Andrea Lorenzani, Ryan MacDonald, Laura Magrini, Jesus Maldonado, Emmanuel Marcq, Alessandra Migliorini, Darius Modirrousta-Galian, Karan Molaverdikhani, Sergio Molinari, Paul Mollière, Vincent Moreau, Giuseppe Morello, Gilles Morinaud, Mario Morvan, Moses, Julianne I., Salima Mouzali, Nariman Nakhjiri, Luca Naponiello, Norio Narita, Valerio Nascimbeni, Athanasia Nikolaou, Vladimiro Noce, Fabrizio Oliva, Pietro Palladino, Andreas Papageorgiou, Vivien Parmentier, Giovanni Peres, Javier Pérez, Santiago Perez-Hoyos, Manuel Perger, Cesare Cecchi Pestellini, Antonino Petralia, Anne Philippon, Arianna Piccialli, Marco Pignatari, Giampaolo Piotto, Linda Podio, Gianluca Polenta, Giampaolo Preti, Theodor Pribulla, Manuel Lopez Puertas, Monica Rainer, Jean-Michel Reess, Paul Rimmer, Séverine Robert, Albert Rosich, Loic Rossi, Duncan Rust, Ayman Saleh, Nicoletta Sanna, Eugenio Schisano, Laura Schreiber, Victor Schwartz, Antonio Scippa, Bálint Seli, Sho Shibata, Caroline Simpson, Oliver Shorttle, Skaf, N., Konrad Skup, Mateusz Sobiecki, Sergio Sousa, Alessandro Sozzetti, Judit Šponer, Lukas Steiger, Paolo Tanga, Paul Tackley, Jake Taylor, Matthias Tecza, Luca Terenzi, Pascal Tremblin, Andrea Tozzi, Amaury Triaud, Loïc Trompet, Shang-Min Tsai, Maria Tsantaki, Diana Valencia, Ann Carine Vandaele, Mathieu Van der Swaelmen, Adibekyan Vardan, Gautam Vasisht, Allona Vazan, Ciro Del Vecchio, Dave Waltham, Piotr Wawer, Thomas Widemann, Paulina Wolkenberg, Gordon Hou Yip, Yuk Yung, Mantas Zilinskas, Tiziano Zingales, Paola Zuppella, University College of London [London] (UCL), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Université de Bordeaux (UB), Agence Spatiale Européenne = European Space Agency (ESA), SRON Netherlands Institute for Space Research (SRON), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Bologna (OABO), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), 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), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), European Space Agency, Agence Spatiale Européenne (ESA), European Space Agency (ESA), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Giovanna Tinetti, Paul Eccleston, Carole Haswell, Pierre-Olivier Lagage, Jérémy Leconte, Theresa Lüftinger, Giusi Micela, Michel Min, Göran Pilbratt, Ludovic Puig, Mark Swain, Leonardo Testi, Diego Turrini, Bart Vandenbussche, Maria Rosa Zapatero Osorio, Anna Aret, Jean-Philippe Beaulieu, Lars Buchhave, Martin Feru, Matt Griffin, Manuel Guedel, Paul Hartogh, Pedro Machado, Giuseppe Malaguti, Enric Pallé, Mirek Rataj, Tom Ray, Ignasi Riba, Robert Szabó, Jonathan Tan, Stephanie Werner, Francesco Ratti, Carsten Scharmberg, Jean-Christophe Salvignol, Nathalie Boudin, Jean-Philippe Halain, Martin Haag, Pierre-Elie Crouzet, Ralf Kohley, Kate Symond, Florian Renk, Andrew Caldwell, Manuel Abreu, Gustavo Alonso, Jerome Amiaux, Michel Berthé, Georgia Bishop, Neil Bowle, Manuel Carmona, Deirdre Coffey, Josep Colomé, Martin Crook, Lucile Désjonquere, José J. Díaz, Rachel Drummond, Mauro Focardi, Jose M. Gómez, Warren Holme, Matthijs Krijger, Zsolt Kovac, Tom Hunt, Richardo Machado, Gianluca Morgante, Marc Ollivier, Roland Ottensamer, Emanuele Pace, Teresa Pagano, Enzo Pascale, Chris Pearson, Søren Møller Pedersen, Moshe Pniel, Stéphane Roose, Giorgio Savini, Richard Stamper, Peter Szirovicza, Janos Szoke, Ian Tosh, Francesc Vilardell, Joanna Barstow, Luca Borsato, Sarah Casewell, Quentin Changeat, Benjamin Charnay, Svatopluk Civiš, Vincent Coudé du Foresto, Athena Cousteni, Nicolas Cowan, Camilla Danielski, Olivier Demangeon, Pierre Drossart, Billy N. Edward, Gabriella Gilli, Therese Encrenaz, Csaba Ki, Anastasia Kokori, Masahiro Ikoma, Juan Carlos Morale, João Mendonça, Andrea Moneti, Lorenzo Mugnai, Antonio García Muñoz, Ravit Helled, Mihkel Kama, Yamila Miguel, Nikos Nikolaou, Isabella Pagano, Olja Panic, Miriam Rengel, Hans Rickman, Marco Rocchetto, Subhajit Sarkar, Franck Selsi, Jonathan Tennyson, Angelos Tsiara, Olivia Venot, Krisztián Vida, Ingo P. Waldmann, Sergey Yurchenko, Gyula Szabó, Rob Zellem, Ahmed Al-Refaie, Javier Perez Alvarez, Lara Anisman, Axel Arhancet, Jaume Ateca, Robin Baeyen, John R. Barne, Taylor Bell, Serena Benatti, Katia Biazzo, Maria Błęcka, Aldo Stefano Bonomo, José Bosch, Diego Bossini, Jeremy Bourgalai, Daniele Brienza, Anna Brucalassi, Giovanni Bruno, Hamish Caine, Simon Calcutt, Tiago Campante, Rodolfo Canestrari, Nick Cann, Giada Casali, Albert Casa, Giuseppe Cassone, Christophe Cara, Ludmila Carone, Nathalie Carrasco, Paolo Chioetto, Fausto Cortecchia, Markus Czupalla, Katy L. Chubb, Angela Ciaravella, Antonio Claret, Riccardo Claudi, Claudio Codella, Maya Garcia Coma, Gianluca Cracchiolo, Patricio Cubillo, Vania Da Peppo, Leen Decin, Clemence Dejabrun, Elisa Delgado-Mena, Anna Di Giorgio, Emiliano Diolaiti, Caroline Dorn, Vanessa Doublier, Eric Doumayrou, Georgina Dransfield, Luc Dumaye, Emma Dunford, Antonio Jimenez Escobar, Vincent Van Eylen, Maria Farina, Davide Fedele, Alejandro Fernández, Benjamin Fleury, Sergio Fonte, Jean Fontignie, Luca Fossati, Bernd Funke, Camille Galy, Zoltán Garai, Andrés García, Alberto García-Rigo, Antonio Garufi, Giuseppe Germano Sacco, Paolo Giacobbe, Alejandro Gómez, Arturo Gonzalez, Francisco Gonzalez-Galindo, Davide Grassi, Caitlin Griffith, Mario Giuseppe Guarcello, Audrey Goujon, Amélie Gressier, Aleksandra Grzegorczyk, Tristan Guillot, Gloria Guilluy, Peter Hargrave, Marie-Laure Hellin, Enrique Herrero, Matt Hill, Benoit Horeau, Yuichi Ito, Niels Christian Jessen, Petr Kabath, Szilárd Kálmán, Yui Kawashima, Tadahiro Kimura, Antonín Knížek, Laura Kreidberg, Ronald Kruid, Diederik J. M. Kruijssen, Petr Kubelík, Luisa Lara, Sebastien Lebonnoi, David Lee, Maxence Lefevre, Tim Lichtenberg, Daniele Locci, Matteo Lombini, Alejandro Sanchez Lopez, Andrea Lorenzani, Ryan MacDonald, Laura Magrini, Jesus Maldonado, Emmanuel Marcq, Alessandra Migliorini, Darius Modirrousta-Galian, Karan Molaverdikhani, Sergio Molinari, Paul Mollière, Vincent Moreau, Giuseppe Morello, Gilles Morinaud, Mario Morvan, Julianne I. Mose, Salima Mouzali, Nariman Nakhjiri, Luca Naponiello, Norio Narita, Valerio Nascimbeni, Athanasia Nikolaou, Vladimiro Noce, Fabrizio Oliva, Pietro Palladino, Andreas Papageorgiou, Vivien Parmentier, Giovanni Pere, Javier Pérez, Santiago Perez-Hoyo, Manuel Perger, Cesare Cecchi Pestellini, Antonino Petralia, Anne Philippon, Arianna Piccialli, Marco Pignatari, Giampaolo Piotto, Linda Podio, Gianluca Polenta, Giampaolo Preti, Theodor Pribulla, Manuel Lopez Puerta, Monica Rainer, Jean-Michel Ree, Paul Rimmer, Séverine Robert, Albert Rosich, Loic Rossi, Duncan Rust, Ayman Saleh, Nicoletta Sanna, Eugenio Schisano, Laura Schreiber, Victor Schwartz, Antonio Scippa, Bálint Seli, Sho Shibata, Caroline Simpson, Oliver Shorttle, N. Skaf, Konrad Skup, Mateusz Sobiecki, Sergio Sousa, Alessandro Sozzetti, Judit Šponer, Lukas Steiger, Paolo Tanga, Paul Tackley, Jake Taylor, Matthias Tecza, Luca Terenzi, Pascal Tremblin, Andrea Tozzi, Amaury Triaud, Loïc Trompet, Shang-Min Tsai, Maria Tsantaki, Diana Valencia, Ann Carine Vandaele, Mathieu Van der Swaelmen, Adibekyan Vardan, Gautam Vasisht, Allona Vazan, Ciro Del Vecchio, Dave Waltham, Piotr Wawer, Thomas Widemann, Paulina Wolkenberg, Gordon Hou Yip, Yuk Yung, Mantas Zilinska, Tiziano Zingale, Paola Zuppella, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), 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 de Paris (UP), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), and Cardon, Catherine
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[SDU] Sciences of the Universe [physics] ,Earth and Planetary Astrophysics (astro-ph.EP) ,[SDU.ASTR.IM] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] ,Settore FIS/05 - Astronomia E Astrofisica ,[SDU]Sciences of the Universe [physics] ,[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] ,[SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] ,FOS: Physical sciences ,Astrophysics - Instrumentation and Methods for Astrophysic ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics - Earth and Planetary Astrophysics ,[SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] - Abstract
Ariel, the Atmospheric Remote-sensing Infrared Exoplanet Large-survey, was adopted as the fourth medium-class mission in ESA's Cosmic Vision programme to be launched in 2029. During its 4-year mission, Ariel will study what exoplanets are made of, how they formed and how they evolve, by surveying a diverse sample of about 1000 extrasolar planets, simultaneously in visible and infrared wavelengths. It is the first mission dedicated to measuring the chemical composition and thermal structures of hundreds of transiting exoplanets, enabling planetary science far beyond the boundaries of the Solar System. The payload consists of an off-axis Cassegrain telescope (primary mirror 1100 mm x 730 mm ellipse) and two separate instruments (FGS and AIRS) covering simultaneously 0.5-7.8 micron spectral range. The satellite is best placed into an L2 orbit to maximise the thermal stability and the field of regard. The payload module is passively cooled via a series of V-Groove radiators; the detectors for the AIRS are the only items that require active cooling via an active Ne JT cooler. The Ariel payload is developed by a consortium of more than 50 institutes from 16 ESA countries, which include the UK, France, Italy, Belgium, Poland, Spain, Austria, Denmark, Ireland, Portugal, Czech Republic, Hungary, the Netherlands, Sweden, Norway, Estonia, and a NASA contribution., Comment: Ariel Definition Study Report, 147 pages. Reviewed by ESA Science Advisory Structure in November 2020. Original document available at: https://www.cosmos.esa.int/documents/1783156/3267291/Ariel_RedBook_Nov2020.pdf/
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- 2021
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21. Constraining the initial planetary population in the gravitational instability model
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Allona Vazan, Ravit Helled, Mariangela Bonavita, Sergei Nayakshin, J. Humphries, University of Zurich, and Humphries, J
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010504 meteorology & atmospheric sciences ,530 Physics ,Gas giant ,Metallicity ,Population ,Brown dwarf ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,1912 Space and Planetary Science ,Planet ,0103 physical sciences ,education ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,education.field_of_study ,Astronomy and Astrophysics ,Accretion (astrophysics) ,Radial velocity ,Space and Planetary Science ,10231 Institute for Computational Science ,3103 Astronomy and Astrophysics ,Protoplanet ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Direct imaging (DI) surveys suggest that gas giants beyond 20 AU are rare around FGK stars. However, it is not clear what this means for the formation frequency of Gravitational Instability (GI) protoplanets due to uncertainties in gap opening and migration efficiency. Here we combine state-of-the-art calculations of homogeneous planet contraction with a population synthesis code. We find DI constraints to be satisfied if protoplanet formation by GI occurs in tens of percent of systems if protoplanets `super migrate' to small separations. In contrast, GI may occur in only a few percent of systems if protoplanets remain stranded at wide orbits because their migration is `quenched' by efficient gap opening. We then use the frequency of massive giants in radial velocity surveys inside 5 AU to break this degeneracy - observations recently showed that this population does not correlate with the host star metallicity and is therefore suspected to have formed via GI followed by inward migration. We find that only the super-migration scenario can sufficiently explain this population whilst simultaneously satisfying the DI constraints and producing the right mass spectrum of planets inside 5 AU. If massive gas-giants inside 5 AU formed via GI, then our models imply that migration must be efficient and that the formation of GI protoplanets occurs in at least a tens of percent of systems., Accepted to MNRAS
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- 2019
22. Ankylosing Spinal Disease—Diagnosis and Treatment of Spine Fractures
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Melanie Barz, Bernhard Meyer, Yu-Mi Ryang, Jens Gempt, Elisabeth Török, and Martin Vazan
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Radiography ,Population ,Comorbidity ,Spinal disease ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Internal fixation ,education ,Aged ,Diffuse Idiopathic Skeletal Hyperostosis ,Aged, 80 and over ,education.field_of_study ,Ankylosing spondylitis ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Spine ,Surgery ,Treatment Outcome ,030220 oncology & carcinogenesis ,Spinal fusion ,Spinal Fractures ,Female ,Spinal Diseases ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Background In patients with ankylosing spinal disease, including ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis, even low-impact trauma can lead to complex injuries. The injuries seem to be highly unstable and associated with greater mortality rates compared with the general spine trauma population. Methods We reviewed the medical records of a consecutive series of 41 patients (34 men, 7 women) with ankylosing spinal disease and unstable traumatic spine injuries who were admitted to our department from 2007 to 2016. Results The mean patient age was 73.4 ± 12.7 years. Of the 41 patients, 24 (58.5%) had ankylosing spondylitis and 17 (41.5%) had diffuse idiopathic skeletal hyperostosis. Low-velocity accidents were documented in 38 patients (92.7%). The most frequent injuries were type B spine fractures (61.0%). Accompanying spinal epidural hematoma was detected using magnetic resonance imaging in 12 patients (29.3%) but was not found by radiography or computed tomography. Of the 41 patients, 24 (58.5%) presented with American Spinal Injury Association impairment scale (AIS) grade E, 6 (14.6%) with grade D, and 8 (19.6%) with grade C or worse. All the patients had undergone internal fixation. All but 1 (97.6%) had received posterior fixation. In 25 (61%), a combined approach was performed. Five patients died of early complications. Of the 36 discharged patients, 11 died during the follow-up period and 1 was lost to follow-up. The surviving 24 patients had a median follow-up of 733 ± 576 days; 21 had AIS grade E, 2 had AIS grade D, and 1 had AIS grade C. Conclusions A thorough diagnostic evaluation with multislice computed tomography and magnetic resonance imaging can reveal injuries that would remain undetected on conventional radiographs. A combined approach or posterior-only fixation seems safe.
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- 2019
23. The evolutionary pathway of polluted proto-planets
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Amy Bonsor, M. G. Brouwers, Chris W. Ormel, and Allona Vazan
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Planet ,Astrobiology - Abstract
1. Introduction:In the traditional core accretion scenario, a planet grows by the subsequent accretion of a solid core and a gaseous envelope [3]. However, the accretion of these solids generates a large amount of heat, which can easily vaporize incoming pebbles and fractured planetesimals before the core has grown massive [1,4,5]. This naturally leads to the formation of planets with polluted envelopes that are characterized by different interior conditions and that follow an altered evolutionary pathway. In this series of papers [1,2+forthcoming], we develop new analytical and numerical models to describe the formation and evolution of polluted planets and link emerging trends in their formation to observations of planetary systems. 2. Formation of polluted planets: Fig. 1. A sketch of the four potential evolutionary phases of a polluted planet. We find that envelope pollution substantially alters the structure of proto-planets in a number of ways and we suggest that their evolution can be described by four distinct phases, sketched in Fig. 1. (I). In the first phase of direct core growth, the envelope is still cold enough for solids to reach the central core. As the planet's internal temperatures rise, an increasing fraction of the accreting solids sublimates and is absorbed in the envelope. This slows down the growth of the core until it halts completely when all incoming solids become vaporized and remain in the envelope. We find that in the case of pebble accretion, this limits the size of the central cores to ‹ 1-2 M⊕, depending on conditions. (II). We refer to the second phase as that of envelope growth, as this is where all the accreted solids end up after direct core growth ends. In our analytical model, we assume that it mixes efficiently with the nebular gas but we relax this assumption in a forthcoming numerical work. Regardless, we find that polluted interiors become very hot and dense due to a higher mean molecular weight, lower adiabatic index and smaller core. Interior temperatures can already reach values in excess of 104 K at only a few Earth masses. Traditional models use the critical core mass as a criterion to identify the transition to runaway gas accretion but this term becomes a meaningless in planets that do not grow their cores beyond a certain size. We therefore suggest the critical metal mass (Mz,crit) as an equivalent criterion to supercede it. It is defined as the total mass in solids (core + vapor) that a planet needs to accrete in order to reach runaway growth. We derive the first expression for this mass: where κrcb is the opacity at the radiative-convective boundary, d is the planet's semi-major axis, Tvap is the vaporization temperature of the solids, is their accretion rate and Mc is the mass of the central core. Planets that form beyond the ice-line accrete a larger fraction of volatile materials and therefore form smaller cores with material that is characterized by lower vaporization temperatures. Both these effects reduce the critical metal mass compared to the inner disk where super-Earths and mini-Neptunes are more resistant to runaway gas accretion. (III). If a planet stops accreting solids before it reaches runaway accretion and while the disk is still present, it enters a phase of embedded cooling. This naturally happens in pebble accretion when a planet reaches the pebble isolation mass and begins to perturb the surrounding disk. The continued inward drift of tiny dust allows the planet to maintain a high opacity, limiting the pace of cooling. Besides this, the dilution of the interior can counteract the contraction of the envelope and further limit nebular accretion, although this requires the interior to remain compositionally mixed. We suggest that a combination of these effects can help explain why Uranus and Neptune did not reach runaway gas accretion, even if their solids flux dried up while the disk was still present. (IV). Finally, the proto-planetary disk will dissipate and the planets eventually enter phase IV of isolated cooling. In traditional models, this is mainly associated with contraction and potential mass loss. We suggest that in the case of a polluted planet, the cooling will eventually lead to the rainout of the vapor interior and generate a second phase of (indirect) core growth after several Gyr. While the process of photo-evaporation should not be altered by this, we find that it makes internal energy release an ineffective mass-loss mechanism. This is because most of the energy is only liberated late in the planet's evolution after substantial contraction, when mass loss from winds is far less efficient. 2.1 Opacity in pebble accretion Fig. 2. Trends in the critical metal mass from the opacity of gas, dust and pebbles. We model the opacity during pebble accretion in a forthcoming work with a combination of molecular, dust and pebble contributions. We find that pebbles can effectively reduce the dust abundance through sweep-up, but only in the early stages when nebular gas accretion is outpaced by the pebble flux. Near the onset of runaway accretion, the opacity displays a dichotomy between the hot inner disk where molecular opacity dominates and the outer disk where dust obscures the envelopes. The result is an opacity valley around 1-3 AU that translates to an equivalent minimum in the critical metal mass at the same location (see Fig. 2), which can help explain the abundance of warm Jupiters in this region. Acknowledgements:This work has benefited from discussions at the ISSI Ice Giants Meetings in Bern 2019 & 2020. Marc Brouwers acknowledges the support of a Royal Society Studentship, RG 160509. References: [1] Brouwers, M. G., Vazan, A., & Ormel, C. W. 2018, A&A, 611, A65 [2] Brouwers, M. G. & Ormel, C. W. 2020, A&A, 634, A15 [3] Pollack, J. B., Hubickyj, O., Bodenheimer, P., et al. 1996, Icarus, 124, 62 [4] Mordasini, C., Mollière, P., Dittkrist, K.-M., Jin, S., & Alibert, Y. 2015, International Journal of Astrobiology, 14, 201 [5] Valletta, C. & Helled, R. 2019, ApJ, 871, 127
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- 2020
24. A New Perspective on the Interiors of Ice-rich Planets: Ice–Rock Mixture Instead of Ice on Top of Rock
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Allona Vazan, Re’em Sari, and Ronit Kessel
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Physics - Geophysics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Space and Planetary Science ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Physics::Atmospheric and Oceanic Physics ,Astrophysics - Earth and Planetary Astrophysics ,Geophysics (physics.geo-ph) ,Physics::Geophysics - Abstract
Ice-rich planets are formed exterior to the water ice-line and thus are expected to contain a substantial amount of ices. The high ice content leads to unique conditions in the interior, under which the structure of a planet is affected by ice interaction with other metals. We apply experimental data of ice-rock interaction at high pressure, and calculate detailed thermal evolution for possible interior configurations of ice-rich planets, in the mass range of super-Earth to Neptunes (5-15 Earth masses). We model the effect of migration inward on the ice-rich interior by including the influences of stellar flux and envelope mass loss. We find that ice and rock are expected to remain mixed, due to miscibility at high pressure, in substantial parts of the planetary interior for billions of years. We also find that the deep interior of planetary twins that have migrated to different distances from the star are usually similar, if no mass loss occurs. Significant mass loss results in separation of the water from the rock on the surface and emergence of a volatile atmosphere of less than 1 percent of the planet's mass. The mass of the atmosphere of water/steam is limited by the ice-rock interaction. We conclude that when ice is abundant in planetary interiors the planet structure may differ significantly from the standard layered structure of a water shell on top of a rocky core. Similar structure is expected in both close-in and further-out planets., Comment: Accepted for publication in ApJ. Updated with extensive appendices on ice-rock interaction. Results and conclusions are unchanged
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- 2022
25. On the aspect ratio of Oumuamua: less elongated shape for irregular surface properties
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Allona Vazan and Re'em Sari
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Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Brightness ,Backscatter ,Aspect ratio ,010308 nuclear & particles physics ,Scattering ,FOS: Physical sciences ,Astronomy and Astrophysics ,Geometry ,Parameter space ,01 natural sciences ,Reflection (mathematics) ,Space and Planetary Science ,Orientation (geometry) ,0103 physical sciences ,Specular reflection ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The large brightness variation in the observed lightcurve of Oumuamua is probably related to its shape, i.e., to the ratio between its longest axis and its shortest axis (aspect ratio). Several approaches found the aspect ratio of Oumuamua to be unusually elongated. Moreover, the spin axis orientation has to be almost perpendicular to the observer in order to obtain such an extreme lightcurve, a configuration which is unlikely. However, interstellar Oumuamua may have different surface properties than we know in our solar system. Therefore, in this work we widen the parameter space for surface properties beyond the asteroid-like models and study its effect on the lightcurve of Oumuamua. We calculate reflection from a rotating ellipsoidal object for four models: Lambertian reflection, specular reflection, single scattering diffusive and backscatter. We then calculate the probability to obtain a lightcurve ratio larger than the observed, as a function of the object aspect ratio, assuming an isotopic spin orientation distribution. We find the elongation of Oumuamua to be less extreme for the Lambertian and specular reflection models. Consequently, the probability to observe the lightcurve ratio of Oumuamua given its unknown spin axis orientation is larger for those models. We conclude that different surface reflection properties may suggest alternatives to the extreme shape of Oumuamua, relieving the need for complicated formation scenario, extreme albedo variation, or unnatural origin. Although the models suggested here are for ideal ellipsoidal shape and ideal reflection method, the results emphasize the importance of surface properties for the derived aspect ratio., Comment: 7 pages, accepted for publication in MNRAS
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- 2020
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26. Association of bone mineral density with reoperation rate following instrumented lumbar spinal fusion: a retrospective cohort and case-control study
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Johannes Kaesmacher, Anna Rienmüller, Felix Zibold, Jan S. Kirschke, Bernhard Meyer, Nico Sollmann, Maximilian T. Löffler, Martin Vazan, Yu-Mi Ryang, Ehab Shiban, and Niklas Loreck
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Bone mineral ,030222 orthopedics ,03 medical and health sciences ,medicine.medical_specialty ,0302 clinical medicine ,business.industry ,Case-control study ,Medicine ,Retrospective cohort study ,business ,030217 neurology & neurosurgery ,Lumbar spinal fusion ,Surgery - Abstract
Background Low bone mineral density (BMD) is believed to influence the outcome of instrumented spinal surgery and can lead to reoperation. Purpose of this retrospective cohort and case-control study was to investigate the association of BMD with the risk of reoperation following instrumented lumbar spinal fusion (LSF). Methods For the cohort analysis, 81 patients were included who received LSF with and without polymethyl methacrylate (PMMA)-augmentation. For the case-control analysis, 18 patients who had reoperation following LSF were matched to 26 patients who did not have reoperation (matching criteria: sex, age ± 5 years, fused levels, and augmentation). Opportunistic BMD screening was performed in perioperative CT scans using asynchronous calibration. Mean BMD was compared between patients with and without reoperation in augmented and non-augmented surgeries. Results In the cohort analysis, prevalence of osteoporosis (BMD < 80 mg/cm³) was 29% in non-augmented and 85% in augmented LSF. Seven of 48 patients with non-augmented (15%) and 4 of 33 patients with augmented LSF (12%) had reoperation. In non-augmented LSF, patients with reoperation had significantly lower BMD than patients without reoperation (p = 0.005). In the case-control analysis, patients with reoperation presented numerically lower BMD of 78.8 ± 33.1 mg/cm³ than patients without reoperation with BMD of 89.4 ± 39.7 mg/cm³ (p = 0.357).Conclusions Prevalence of osteoporosis in patients undergoing LSF is relatively high. Patients with reoperation following LSF showed slightly lower BMD compared to matched patients without reoperation, but the difference was not statistically significant. Opportunistic BMD screening in preoperative CT is feasible and can provide valuable information about osteoporotic bone status.
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- 2019
27. Pregnancy Outcomes in Women With Rheumatic Mitral Valve Disease Results From the Registry of Pregnancy and Cardiac Disease
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Van Hagen I. M., Thorne S. A., Taha N., Youssef G., Elnagar A., Gabriel H., ElRakshy Y., Iung B., Johnson M. R., Hall R., Roos-Hesselink J. W., Ferrari R., Maggioni A. P., Marelli A., Webb G., Kaemmerer H., Popelova J., Sliwa K., Tavazzi L., Anthony Parsonage W., Stein J., Elkayam U., Thilen U., Budts W., Ruys T., Ferreira T., Missiamenou V., Folkesson Lefrancq E., Aquieri A., Ruda Vega H., Vazquez Blanco M., Lust K., Fagermo N., Donhauser E., Gasimov Z., Jahangirov T., Hasanova I., De Backer J., Demulier L., de Hosson M., Beckx M., Moissens M., Kovacevic-Preradovic T., Kozic M., Lovric M., Vilas Freire C., Chilingirova N., Kratunkov P., Montesclaros A. R., Beaubien E., Gordon E., Walter L., Lindsay C., Wahab N., Vavera Z., El Nagar A., Ebaid H. H., A. El Sayed Makled W., Dardier A., Shabaan M., Eltamawey K., Gamal Abd-El Aziz M., Saad A., Aboleineen W., Ashour Z., Sorour K., A. Meguid Mahdy M., Iserin L., Ladouceur M., Cohen S., Maisuradze D., Mebus S., Gembruch U., Hammerstingl C., Merz W. M., Wald C., Hellige A., Baumgartner H., Schmidt R., Motz R., Olsson A., Berger F., Nagdyman N., Frogoudaki A., Anastasiou-Nana M., Temesvari A., Kohalmi D., Balint H., Merkely B., Liptai C., Bowen M., Cullen M., Thornton P., Husarova V., Blatt A., Elbaz-Greener G., Moravsky G., Vered Z., Vazan Fuhrmann A., Shotan A., Goland S., Festa P., Ait Ali L., Sinagra G., Puggia I., D'Agata Mottolese B., Carmina M. G., Romeo C., Crepaz R., Fesslova V., Azzarelli A., Baldi D., Bovenzi F., Donvito V., Vasario E., Todros T., Niwa K., Mussagaliyeva A., Mekebekova D., Sharipova S., Zaliunas R., Jonkaitiene R., Petrauskaite J., Gumbiene L., Jovanova S., Cassar A., Caruana M., Karamermer Y., Cornette J. M. J., van Dijk A., Bellersen L., Duijnhouwer T., De Groot C., PG Pieper E., van Oppen C., Polak P., Wajon E., Wagenaar L., Estensen M., Lesniak-Sobelga A., Podolec P., Wisniowska-Smialek S., Trybuch A., Hoffman P., Cichocka-Radwan A., Lelonek M., Sobczak S., Faflik U., Tomaszuk-Kazberuk A., Przepiesc J., Gil M., Plaskota K., Trojnarska O., Guerra N., de Sousa L., Petrescu V., Ginghina C., Jurcut R., Mircea Coman I., Ravilevich Gaisin I., Valeryevna Shilina L., Sharashkina N., Tkacheva O., Ivanov D., Irtyuga O., Jovovic L., Prokselj K., Kozelj M., Elliott C., Galian-Gay L., Pijuan-Domenech A., Subirana-Domenech M. T., Tornos P., Murga N., M. Oliver J., Escribano-Subias P., J. Ruiz-Cano M., Delgado-Jimenez J., Furenas E., Dellborg M., Schwerzmann M., Bouchardy J., Rutz T., Tobler D., Sarac L., Batukan Esen O., Catirli Enar S., Al Mulla A., Bazargani N., Al Hatou E., Farook F., Almahmeed W., Cardiology, Van Hagen, I. M., Thorne, S. A., Taha, N., Youssef, G., Elnagar, A., Gabriel, H., Elrakshy, Y., Iung, B., Johnson, M. R., Hall, R., Roos-Hesselink, J. W., Ferrari, R., Maggioni, A. P., Marelli, A., Webb, G., Kaemmerer, H., Popelova, J., Sliwa, K., Tavazzi, L., Anthony Parsonage, W., Stein, J., Elkayam, U., Thilen, U., Budts, W., Ruys, T., Ferreira, T., Missiamenou, V., Folkesson Lefrancq, E., Aquieri, A., Ruda Vega, H., Vazquez Blanco, M., Lust, K., Fagermo, N., Donhauser, E., Gasimov, Z., Jahangirov, T., Hasanova, I., De Backer, J., Demulier, L., de Hosson, M., Beckx, M., Moissens, M., Kovacevic-Preradovic, T., Kozic, M., Lovric, M., Vilas Freire, C., Chilingirova, N., Kratunkov, P., Montesclaros, A. R., Beaubien, E., Gordon, E., Walter, L., Lindsay, C., Wahab, N., Vavera, Z., El Nagar, A., Ebaid, H. H., A. El Sayed Makled, W., Dardier, A., Shabaan, M., Eltamawey, K., Gamal Abd-El Aziz, M., Saad, A., Aboleineen, W., Ashour, Z., Sorour, K., A. Meguid Mahdy, M., Iserin, L., Ladouceur, M., Cohen, S., Maisuradze, D., Mebus, S., Gembruch, U., Hammerstingl, C., Merz, W. M., Wald, C., Hellige, A., Baumgartner, H., Schmidt, R., Motz, R., Olsson, A., Berger, F., Nagdyman, N., Frogoudaki, A., Anastasiou-Nana, M., Temesvari, A., Kohalmi, D., Balint, H., Merkely, B., Liptai, C., Bowen, M., Cullen, M., Thornton, P., Husarova, V., Blatt, A., Elbaz-Greener, G., Moravsky, G., Vered, Z., Vazan Fuhrmann, A., Shotan, A., Goland, S., Festa, P., Ait Ali, L., Sinagra, G., Puggia, I., D'Agata Mottolese, B., Carmina, M. G., Romeo, C., Crepaz, R., Fesslova, V., Azzarelli, A., Baldi, D., Bovenzi, F., Donvito, V., Vasario, E., Todros, T., Niwa, K., Mussagaliyeva, A., Mekebekova, D., Sharipova, S., Zaliunas, R., Jonkaitiene, R., Petrauskaite, J., Gumbiene, L., Jovanova, S., Cassar, A., Caruana, M., Karamermer, Y., Cornette, J. M. J., van Dijk, A., Bellersen, L., Duijnhouwer, T., De Groot, C., PG Pieper, E., van Oppen, C., Polak, P., Wajon, E., Wagenaar, L., Estensen, M., Lesniak-Sobelga, A., Podolec, P., Wisniowska-Smialek, S., Trybuch, A., Hoffman, P., Cichocka-Radwan, A., Lelonek, M., Sobczak, S., Faflik, U., Tomaszuk-Kazberuk, A., Przepiesc, J., Gil, M., Plaskota, K., Trojnarska, O., Guerra, N., de Sousa, L., Petrescu, V., Ginghina, C., Jurcut, R., Mircea Coman, I., Ravilevich Gaisin, I., Valeryevna Shilina, L., Sharashkina, N., Tkacheva, O., Ivanov, D., Irtyuga, O., Jovovic, L., Prokselj, K., Kozelj, M., Elliott, C., Galian-Gay, L., Pijuan-Domenech, A., Subirana-Domenech, M. T., Tornos, P., Murga, N., M. Oliver, J., Escribano-Subias, P., J. Ruiz-Cano, M., Delgado-Jimenez, J., Furenas, E., Dellborg, M., Schwerzmann, M., Bouchardy, J., Rutz, T., Tobler, D., Sarac, L., Batukan Esen, O., Catirli Enar, S., Al Mulla, A., Bazargani, N., Al Hatou, E., Farook, F., and Almahmeed, W.
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Registrie ,Cardiac & Cardiovascular Systems ,VALVULAR HEART-DISEASE ,heart disease ,Disease ,030204 cardiovascular system & hematology ,Cardiovascular ,0302 clinical medicine ,Pregnancy ,Models ,Mitral valve ,Rheumatic heart disease ,Valvular heart disease ,Women ,Women and minorities ,Adult ,Female ,Humans ,Prospective Studies ,Mitral Valve Insufficiency ,Models, Cardiovascular ,Pregnancy Complications, Cardiovascular ,Pregnancy Outcome ,Registries ,Rheumatic Heart Disease ,Prospective cohort study ,1102 Cardiorespiratory Medicine and Haematology ,030219 obstetrics & reproductive medicine ,valvular heart disease ,ROPAC Investigators and EORP Team ,SOUTH-AFRICA ,EUROPEAN-SOCIETY ,OUTPUT ,medicine.anatomical_structure ,cardiovascular system ,Cardiology ,Cardiology and Cardiovascular Medicine ,Life Sciences & Biomedicine ,Women and minoritie ,Human ,medicine.medical_specialty ,DEATHS ,STENOSIS ,1117 Public Health and Health Services ,03 medical and health sciences ,Physiology (medical) ,Internal medicine ,MANAGEMENT ,medicine ,Pregnancy outcomes ,Science & Technology ,business.industry ,1103 Clinical Sciences ,medicine.disease ,Pregnancy Complications ,Prospective Studie ,Stenosis ,Peripheral Vascular Disease ,Cardiovascular System & Hematology ,Cardiovascular System & Cardiology ,rheumatic ,business - Abstract
Background: Cardiac disease is 1 of the major causes of maternal mortality. We studied pregnancy outcomes in women with rheumatic mitral valve disease. Methods: The Registry of Pregnancy and Cardiac Disease is an international prospective registry, and consecutive pregnant women with cardiac disease were included. Pregnancy outcomes in all women with rheumatic mitral valve disease and no prepregnancy valve replacement is described in the present study (n=390). A maternal cardiac event was defined as cardiac death, arrhythmia requiring treatment, heart failure, thromboembolic event, aortic dissection, endocarditis, acute coronary syndrome, and hospitalization for other cardiac reasons or cardiac intervention. Associations between patient characteristics and cardiac outcomes were checked in a 3-level model (patient–center–country). Results: Most patients came from emerging countries (75%). Mitral stenosis (MS) with or without mitral regurgitation (MR) was present in 273 women, isolated MR in 117. The degree of MS was mild in 20.9%, moderate in 39.2%, severe in 19.8%, and severity not classified in the remainder. Maternal death during pregnancy occurred in 1 patient with severe MS. Hospital admission occurred in 23.1% of the women with MS, and the main reason was heart failure (mild MS 15.8%, moderate 23.4%, severe 48.1%; P 1 was an independent predictor of maternal cardiac events. Follow-up at 6 months postpartum was available for 53%, and 3 more patients died (1 with severe MS, 1 with moderate MS, 1 with moderate to severe MR). Conclusions: Although mortality was only 1.9% during pregnancy, ≈50% of the patients with severe rheumatic MS and 23% of those with significant MR developed heart failure during pregnancy. Prepregnancy counseling and considering mitral valve interventions in selected patients are important to prevent these complications.
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- 2018
28. Using data mining methods for manufacturing process control
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Pavol Tanuska, Pavel Vazan, Michal Kebisek, Zuzana Cervenanska, and D. Janikova
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0209 industrial biotechnology ,Computer science ,Manufacturing process ,Process (engineering) ,Control (management) ,02 engineering and technology ,Manufacturing systems ,computer.software_genre ,020901 industrial engineering & automation ,Control and Systems Engineering ,0202 electrical engineering, electronic engineering, information engineering ,Predictive Model Markup Language ,Production (economics) ,020201 artificial intelligence & image processing ,Data mining ,computer - Abstract
The Industry 4.0 concept assumes that modern manufacturing systems generate huge amounts of data that must be collected, stored, managed and analysed. The case study is focused on predicting the manufacturing process behaviour according to production data. The paper presents the way of gaining knowledge about the future behaviour of manufacturing system by data mining predictive tasks. The proposed simulation model of the real manufacturing process was designed to obtain the data necessary for the control process. The predictions of the manufacturing process behaviour were implemented varying the input parameters using selected methods and techniques of data mining. The predicted process behaviour was verified using the simulation model. The authors analysed different methods. The neural network method was selected for deploying new data by PMML files in the final phases. The objectives of the research are to design and verify the data mining tools in order to support the manufacturing system control by aiming at improving the decisionmaking process. Based on the prediction of the goal production outcomes, the actual control strategies can be precisely modified. Then they can be used in real manufacturing system without risks.
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- 2017
29. 18-1: Invited Paper : Ultra-High-Brightness 2K x 2K Full-Color OLED Microdisplay Using Direct Patterning of OLED Emitters
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Fridrich Vazan, Evan P. Donoghue, Qi Wang, Laurie Sziklas, Russell S. Draper, David A. Fellowes, Ilyas I. Khayrullin, Olivier Prache, Amalkumar P. Ghosh, Tariq Ali, Kerry Tice, and lhor Wacyk
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010302 applied physics ,Brightness ,Materials science ,business.industry ,sRGB ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Gamut ,AMOLED ,2K resolution ,Backplane ,0103 physical sciences ,OLED ,Optoelectronics ,Augmented reality ,0210 nano-technology ,business - Abstract
The performance details of a full-color 2K x 2K resolution OLED microdisplay with a brightness of 5,000 cd/m2will be presented. The microdisplay was built on a CMOS-based silicon backplane using direct patterning of the primary-color OLED emitters. Additionally, the color gamut of the microdisplays were increased to meet sRGB requirements. Such microdisplays will be ideally suited for wearable VR (virtual reality) and AR (augmented reality) applications.
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- 2017
30. Acute dark chocolate ingestion is beneficial for hemodynamics via enhancement of erythrocyte deformability in healthy humans
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Jana Muchová, Rastislav Vazan, Martina Horvathova, Iveta Bernatova, K. Frimmel, Jana Radosinska, and Maria Vidosovicova
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Adult ,Male ,0301 basic medicine ,Erythrocytes ,Endocrinology, Diabetes and Metabolism ,Hemodynamics ,030204 cardiovascular system & hematology ,Dark chocolate ,Nitric Oxide ,Antioxidants ,Nitric oxide ,Eating ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,food ,Reference Values ,Erythrocyte Deformability ,Animals ,Humans ,Ingestion ,Erythrocyte deformability ,Food science ,Chocolate ,chemistry.chemical_classification ,Cacao ,Reactive oxygen species ,Nutrition and Dietetics ,Polyphenols ,food.food ,Diet ,Milk Chocolate ,Milk ,030104 developmental biology ,chemistry ,Biochemistry ,Female ,Biologically active substances ,Plant Preparations - Abstract
Erythrocyte deformability is an important property of erythrocytes that considerably affects blood flow and hemodynamics. The high content of polyphenols present in dark chocolate has been reported to play a protective role in functionality of erythrocytes. We hypothesized that chocolate might influence erythrocytes not only after repeated chronic intake, but also immediately after its ingestion. Thus, we determined the acute effect of dark chocolate and milk (with lower content of biologically active substances) chocolate intake on erythrocyte deformability. We also focused on selected factors that may affect erythrocyte deformability, specifically nitric oxide production in erythrocytes and total antioxidant capacity of plasma. We determined posttreatment changes in the mentioned parameters 2hours after consumption of chocolate compared with their levels before consumption of chocolate. In contrast to milk chocolate intake, the dark chocolate led to a significantly higher increase in erythrocyte deformability. Nitric oxide production in erythrocytes was not changed after dark chocolate intake, but significantly decreased after milk chocolate. The plasma total antioxidant capacity remained unaffected after ingestion of both chocolates. We conclude that our hypothesis was confirmed. Single ingestion of dark chocolate improved erythrocyte deformability despite unchanged nitric oxide production and antioxidant capacity of plasma. Increased deformability of erythrocytes may considerably improve rheological properties of blood and thus hemodynamics in humans, resulting in better tissue oxygenation.
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- 2017
31. Minimally invasive transforaminal lumbar interbody fusion versus open transforaminal lumbar interbody fusion: a technical description and review of the literature
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Bernhard Meyer, Jens Gempt, Niels Buchmann, Martin Vazan, and Yu Mi Ryang
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medicine.medical_specialty ,Visual analogue scale ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Lumbar interbody fusion ,medicine ,Humans ,Minimally Invasive Surgical Procedures ,Surgical Wound Infection ,Neuroradiology ,Patient discharge ,030222 orthopedics ,Lumbar Vertebrae ,medicine.diagnostic_test ,business.industry ,Interventional radiology ,Oswestry Disability Index ,Surgery ,Spinal Fusion ,Neurology (clinical) ,Neurosurgery ,Implant ,business ,030217 neurology & neurosurgery - Abstract
Minimally invasive spine surgery (MISS) has been increasingly advocated during the last decade with new studies being reported every year. Minimally invasive spine procedures, such as minimally invasive transforaminal interbody fusion (MI-TLIF), have been introduced to reduce approach-related muscle trauma, to minimise blood loss, and to achieve faster wound healing, quicker ambulation and earlier patient discharge. The aim of this article was to give a comprehensive review of the available English literature comparing open TLIF with MI-TLIF techniques published or available online between 1990 and 2014 as identified by an electronic database search on http://www.ncbi.nlm.nih.gov/pubmed . Fourteen relevant studies comparing MI-TLIF and open TLIF cohorts could be identified. MI-TLIF seems to be a valid alternative to open TLIF. Both methods yield good clinical results with similar improvements of Oswestry Disability Index (ODI) and visual analogue scale (VAS) on follow-up. There seems to be no significant differences in clinical outcome and fusion rates on comparison. These results are consistent throughout all reported studies in this review. The most pronounced benefits of MI-TLIF are a significant reduction of blood loss, shorter lengths of hospital stay (LOHS) and lower surgical site infection rates. On the downside, MI-TLIF seems to be associated with significantly higher intraoperative radiation doses, a shallow learning curve, at least in the beginning, longer operating times and potentially more frequent implant failures/cage displacements and revision surgeries.
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- 2017
32. L5 corpectomy—the lumbosacral segmental geometry and clinical outcome—a consecutive series of 14 patients and review of the literature
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Florian Ringel, Bernhard Meyer, Yu-Mi Ryang, Felix Zibold, Martin Vazan, Jens Gempt, Julia Gerhardt, and Insa Janssen
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Adult ,Male ,Spondylodiscitis ,medicine.medical_specialty ,medicine.medical_treatment ,Geometry ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,medicine ,Humans ,Surgical Wound Infection ,030212 general & internal medicine ,Corpectomy ,Aged ,Aged, 80 and over ,Lumbar Vertebrae ,medicine.diagnostic_test ,business.industry ,Implant failure ,Interventional radiology ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Pseudarthrosis ,Spinal Fusion ,Spinal fusion ,Lordosis ,Female ,Neurology (clinical) ,Neurosurgery ,Tomography, X-Ray Computed ,business ,030217 neurology & neurosurgery ,Lumbosacral joint - Abstract
We analyzed the lumbosacral segmental geometry and clinical outcome in patients undergoing L5 corpectomy. Fourteen consecutive patients who underwent L5 (n = 12) or L4 + 5 (n = 2) corpectomy at our department between January 2010 and April 2015 were included. All patients underwent a baseline physical and neurologic examination on admission. The diagnostic routine included MRI and CT scans and, if possible, an upright X-ray of the lumbar spine before and after surgery. The local lordosis angle [L4(L3)-S1] was measured. The most common pathology was infection (N = 7), followed by neoplastic disease (n = 3), pseudarthrosis (n = 2) after previous spinal fusion procedures and burst fractures (n = 2) of the L5 vertebral body. We observed seven complications (2 intraoperative; 5 postoperative) in five (36%) patients. Three patients needed revision surgery because of cage subsidence and/or dislodgement (21%). Additional anterior plating was used in two of the revision surgeries to secure the cage. Two spondylodiscitis patients (14%) with complications died of sepsis. Of the 12 remaining patients, 8 were available for follow-up. L5 corpectomy is a technically challenging but feasible procedure even though the overall complication rate can be as high as 36%. The radiologic and clinical outcome seems to be better in patients with a small lordosis angle between L4(L3) and S1, since an angle of >50 degrees seems to facilitate cage dislodgement. Anterior plating should be considered in these cases to prevent implant failure.
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- 2017
33. The impact of selected priority rules on production goals
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Pavel Vazan, Gabriela Krizanova, Janette Kotianová, and Zuzana Cervenanska
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0209 industrial biotechnology ,Job shop scheduling ,Operations research ,Least slack time scheduling ,Computer science ,05 social sciences ,Scheduling (production processes) ,Flexible manufacturing system ,02 engineering and technology ,020901 industrial engineering & automation ,FIFO and LIFO accounting ,Due date ,0502 economics and business ,Discrete event simulation ,Queue ,050203 business & management - Abstract
The paper presents the outcome of a study that dealt with scheduling of operations and in particular with the impact of selected priority rules on production goals. The impact of the priority rules was examined on a simulation model of the smart flexible manufacturing system with interchangeable workplaces. These problems are characterized as job shop scheduling problems. The study documents the influence of the five selected priority rules FIFO (First in First out), EDD (Earliest Due Date), STR (Slack Time Remaining), STR/OP (Slack Time Remaining per Operation) and SQNO (Shortest Queue at the Next Operation) on chosen production objectives. The effect of applied priority rule has been studied at a different production system loading. The evaluation of experimental results and their synthesis conduce to the formulation of knowledge for the real use of these priority rules in the scheduling of operations.
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- 2019
34. Association of bone mineral density with reoperation rate following instrumented lumbar spinal fusion
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Löffler, Maximilian T., Loreck, Niklas, Kaesmacher, Johannes, Zibold, Felix, Shiban, Ehab, Rienmüller, Anna, Vazan, Martin, Meyer, Bernhard, Ryang, Yu-Mi, and Kirschke, Jan S.
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musculoskeletal diseases ,FOS: Biological sciences ,Quantitative Biology - Tissues and Organs ,Tissues and Organs (q-bio.TO) - Abstract
Low bone mineral density (BMD) is believed to influence the outcome of instrumented spinal surgery and can lead to reoperation. Purpose of this observational and case-control study was to investigate the association of BMD with the risk of reoperation following instrumented lumbar spinal fusion (LSF). For the observational study, 81 patients were included who received LSF with and without augmentation. For the case-control study, 18 patients who had reoperation following LSF were matched to 26 patients who did not have reoperation (matched by sex, age +/- 5 years, fused levels and PMMA-augmentation). Opportunistic BMD screening was performed in perioperative CT scans using asynchronous calibration. Mean BMD was compared between patients with and without reoperation in augmented and non-augmented surgeries. In the observational study, prevalence of osteoporosis (BMD < 80 mg/cc) was 29% in non-augmented and 85% in augmented LSF. Seven of 48 patients with non-augmented (15%) and 4 of 33 patients with augmented LSF (12%) had reoperation. In non-augmented LSF, patients with reoperation had significantly lower BMD than patients without reoperation (P = 0.005). The best cut-off to predict reoperation after non-augmented LSF was BMD < 83.7 mg/cc. In the case-control study, patients with reoperation presented numerically lower BMD of 78.8 +/- 33.1 mg/cc than patients without reoperation with BMD of 89.4 +/- 39.7 mg/cc (P = 0.357). Despite much lower BMD surgeries with PMMA-augmentation showed no higher reoperation rate compared to non-augmented surgeries. Patients with reoperation following LSF showed slightly lower BMD compared to matched patients without reoperation, but the difference was not statistically significant. Opportunistic BMD screening can be performed in preoperative CT, thus informing about osteoporotic bone, a potential risk factor of surgery failure., 16 pages, 2 figures, 4 tables
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- 2019
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35. Life Beyond the Solar System: Remotely Detectable Biosignatures
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Domagal-Goldman, S., Kiang, N., Parenteau, N., Kamakolanu, U., Finster, K., Martin-Torres, J., Danielache, S., DasSarma, P., Tamura, M., Hori, Y., Rugheimer, S., Hartnett, H., Stockwell, B., Vazan, A., Hu, R., Cronin, L., Méndez, A., Smith, H., Demergasso, C., Meadows, V., Blank, D., Grenfell, J., Kane, S., Gavilan, L., Tan, G., Plavchan, P., Fauchez, T., Patty, C., Telesco, C., Shkolnik, E., Lyons, T., Owens, J., López-Morales, M., Lustig-Yaeger, J., ten Kate, I., Banerjee, S., Sohl, L., Gao, P., Lopez, E., Corkrey, R., Molaverdikhani, K., Deming, D., Dong, C., O'Meara, J., Kite, E., Rogers, L., Robinson, T., Tanner, A., Cleaves, H., Cahoy, K., Walker, S., Caldwell, D., Dressing, C., Ngo, H., Cochran, W., Cadillo-Quiroz, H., Blecic, J., Laine, P., Solmaz, A., Ramirez, K., Theiling, B., Dodson-Robinson, S., Zimmerman, N., Line, M., Marchis, F., Redfield, S., Pahlevan, K., Walkowicz, L., Gaudi, B., Curry, S., Pidhorodetska, D., Pyo, T., Chopra, A., Hinkel, N., Young, P., Angerhausen, D., Apai, D., Arney, G., Airapetian, V., Batalha, N., Catling, D., Cockell, C., Deitrick, R., Del Genio, A., Fisher, T., Fujii, Y., Gelino, D., Harman, C., Hegde, S., Kaçar, B., Krissansen-Totten, J., Lenardic, A., Mandt, K., Moore, W., Narita, N., Olson, S., Pallé, E., Rauer, H., Reinhard, C., Roberge, A., Schneider, J., Siegler, N., and Stapelfeldt, K.
- Abstract
This white paper reviews the scientific community's ability to use data from future telescopes to search for life on exoplanets. It summarizes products from the Exoplanet Biosignatures Workshop Without Walls (EBWWW). This effort led to papers that constituted the Exoplanet Analysis Group's (ExoPAG) 16th Science Assessment Group (SAG 16).
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- 2019
36. The impact of left ventricular ejection fraction on heart failure patients with pulmonary hypertension
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Liaz Zilberman, Shemy Carasso, Offer Amir, Robert Klempfner, Avraham Shotan, Nir Shlomo, Sorel Goland, Barak Zafrir, Evgeny Radzishevsky, Jean Marc Weinstein, Alicia Vazan, Robert Dragu, Wadi Kinany, Tal Hasin, Elad Maor, and Liza Grosman-Rimon
- Subjects
Pulmonary and Respiratory Medicine ,Male ,medicine.medical_specialty ,Hypertension, Pulmonary ,Cardiovascular risk factors ,Blood Pressure ,030204 cardiovascular system & hematology ,Critical Care and Intensive Care Medicine ,Ventricular Function, Left ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine.artery ,medicine ,Prevalence ,Humans ,Prospective Studies ,Registries ,Israel ,Aged ,Aged, 80 and over ,Heart Failure ,High prevalence ,Ejection fraction ,business.industry ,Hazard ratio ,Stroke Volume ,Middle Aged ,medicine.disease ,Prognosis ,Pulmonary hypertension ,Increased risk ,030228 respiratory system ,Echocardiography ,Heart failure ,Pulmonary artery ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background The most common cause of pulmonary hypertension (PH) in developed countries is left heart disease (LHD, group 2 PH). The development of PH in heart failure (HF) patients is indicative of worse outcomes. Objective The aim of this study was to evaluate the long term outcomes of HF patients with PH in a national long-term registry. Methods Study included 9 cardiology centers across Israel between 01/2013–01/2015, with a 12-month clinical follow-up and 24-month mortality follow-up. Patients were age ≥18 years old with HF and pre-inclusion PH due to left heart disease determined by echocardiography [estimated systolic pulmonary arterial pressure (SPAP) ≥ 50 mmHg]. Patients were categorized into 3 groups: HF with reduced (HFrEF Results The registry included 372 patients, with high prevalence of cardiovascular risk factors. Median HF duration was 4 years and 65% were in severe HF New York Heart Association (NYHA) classification ≥3. Mean systolic pulmonary artery pressure (SPAP) was 62 ± 11 mmHg. During 2-years of follow-up, 54 patients (15%) died. Univariable predictors of mortality included NYHA grade 3–4, chronic renal failure, and SPAP ≥ 65 mmHg. Severe PH was associated with mortality in HFpEF, but not HFmrEF or HFrEF, and remained significant after multivariable adjustment with an adjusted hazard ratio of 2.99, (95%CI 1.29–6.91, p = 0.010). Conclusions The combination of HFpEF with severe PH was independently associated with increased mortality. Currently, HFpEF patients are included with group 2 PH patients. Defining HFpEF with severe PH as a sub-class may be more appropriate, as these patients are at increased risk and deserve special consideration.
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- 2018
37. How planets grow by pebble accretion
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Allona Vazan, Chris W. Ormel, and M. G. Brouwers
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Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Equation of state ,Opacity ,Metallicity ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Radius ,Accretion (astrophysics) ,Atmosphere ,Space and Planetary Science ,Planet ,Astrophysics::Solar and Stellar Astrophysics ,Stellar structure ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
During their formation, planets form large, hot atmospheres due to the ongoing accretion of solids. It has been customary to assume that all solids end up at the center constituting a "core" of refractory materials, whereas the envelope remains metal-free. Recent work, as well as observations by the JUNO mission, indicate however that the distinction may not be so clear cut. Indeed, small silicate, pebble-sized particles will sublimate in the atmosphere when they hit the sublimation temperature (T ~ 2,000 K). In this paper we extend previous analytical work to compute the properties of planets under such a pebble accretion scenario. We conduct 1D numerical calculations of the atmosphere of an accreting planet, solving the stellar structure equations, augmented by a non-ideal equation of state that describes a hydrogen/helium-silicate vapor mixture. Calculations terminate at the point where the total mass in metal equals that of the H/He gas, which we numerically confirm as the onset of runaway gas accretion. When pebbles sublimate before reaching the core, insufficient (accretion) energy is available to mix dense, vapor-rich lower layers with the higher layers of lower metallicity. A gradual structure in which Z decreases with radius is therefore a natural outcome of planet formation by pebble accretion. We highlight, furthermore, that (small) pebbles can act as the dominant source of opacity, preventing rapid cooling and presenting a channel for (mini-)Neptunes to survive in gas-rich disks. Nevertheless, once pebble accretion subsides, the atmosphere rapidly clears followed by runaway gas accretion. We consider atmospheric recycling to be the more probable mechanisms that have stalled the growth of these planets' envelopes., Comment: Accepted for publication in A&A
- Published
- 2021
38. 62-1:Invited Paper: Directly Patterened 2645 PPI Full Color OLED Microdisplay for Head Mounted Wearables
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Fridrich Vazan, Evan P. Donoghue, Kerry Tice, David A. Fellowes, Ihor Wacyk, Russell S. Draper, Laurie Sziklas, Amalkumar P. Ghosh, Tariq Ali, and Ilyas I. Khayrullin
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010302 applied physics ,Computer science ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Wearable computer ,Optical head-mounted display ,02 engineering and technology ,Virtual reality ,021001 nanoscience & nanotechnology ,01 natural sciences ,AMOLED ,CMOS ,Backplane ,Computer graphics (images) ,0103 physical sciences ,RGB color model ,Color filter array ,0210 nano-technology ,ComputingMethodologies_COMPUTERGRAPHICS - Abstract
The world's first directly patternedfull-color OLED microdisplay with > 2600 ppi will be presented. This display is built on a 1920x1200-pixel CMOS backplane and uses RGB emitters, eliminating the need for color filters. This technology results in very-high-luminance microdisplays, ideally suited for wearable AR and VR applications.
- Published
- 2016
39. Effect of chronic intake of liquid nutrition on stomach and duodenum morphology
- Author
-
Michal Miko, Michaela Vrabcova, Rastislav Vazan, Ivan Varga, Boris Mravec, and Livia Mikuska
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Histology ,Morphology (linguistics) ,Duodenum ,Crypt ,Biology ,03 medical and health sciences ,Intestinal mucosa ,Internal medicine ,Stomach Mass ,medicine ,Animals ,Intestinal Mucosa ,Rats, Wistar ,030109 nutrition & dietetics ,Stomach ,digestive, oral, and skin physiology ,Muscle, Smooth ,Organ Size ,Cell Biology ,General Medicine ,medicine.disease ,Obesity ,Small intestine ,Diet ,medicine.anatomical_structure ,Endocrinology - Abstract
Changes in the quantity and/or quality of food intake have been shown to be associated with morphological and functional alterations of the gastrointestinal system. To examine this, we investigated the effect of chronic liquid nutrition intake (Fresubin) on stomach and duodenum morphology in Wistar rats fed liquid nutrition during different developmental periods. We used four groups of rats: a) control group (CON) fed pelleted chow for 130days; b) liquid nutrition group (LN) fed liquid nutrition for 130days; c) liquid nutrition juvenile group (LNJ) fed liquid nutrition for 70days and then pelleted food for 60days; d) liquid nutrition adult group (LNA) fed pelleted chow for 70days and then liquid nutrition for 60days. We found that LN and LNA rats showed a significant reduction of empty stomach mass compared to CON animals, while stomach and duodenal longitudinal muscle layer thickness did not differ between groups. Villus height was increased only in LNA animals, while villus width was increased in both LN and LNA rats. Crypt depth was reduced in LNJ. However, liquid nutrition intake did not affect villus height/crypt depth ratio, nor number of goblet cells. We found that chronic intake of liquid nutrition affects some morphological parameters of the stomach and duodenum but these changes were not homogenous between experimental groups. Interestingly, transition from liquid nutrition to solid food reversed the alterations of stomach weight as well as villus width induced by intake of liquid nutrition in LNA rats. Our data indicate that morphological and functional changes in the gastrointestinal system induced by qualitative and quantitative changes in food intake are at least partially reversible. Therefore, specific diets may be used potentially as adjuvant treatment for modulating the progression of gastrointestinal diseases by affecting stomach and small intestine morphology.
- Published
- 2016
40. Study of Nitrogen Use Efficiency Indices in the Double Cropping Rotations of Wheat (Triticum aestivum L.) in Ilam
- Author
-
Farzad Paknejad, Mehrshad Barary, Ali Kashani, Saeed Vazan, and R Nasri
- Subjects
Nitrogen uptake efficiency ,Nitrogen use efficiency ,Nitrogen utilization efficiency ,Engineering ,Rotation ,business.industry ,lcsh:S ,food and beverages ,chemistry.chemical_element ,Multiple cropping ,lcsh:S1-972 ,Nitrogen ,lcsh:Agriculture ,Agronomy ,chemistry ,Wheat ,lcsh:Agriculture (General) ,business - Abstract
This study was carried out under temperate climate condition of Ilam province, Iran, during 2012-2013 growing season to determine the suitable crop rotation for enhancing nitrogen uptake, utilization, and use efficiency of wheat. A two factor experiment was laid out as split plot arrangement (RCBD) with four replications. The main plots consisted of 6 pre-sowing plant treatments (control, Perko, Buko, Clover, Oilseed radish and combination of three plants Ramtil, Phaselia, Clover), and sub-plots were allocated to four levels of nitrogen fertilizer (Zero, conventionally recommended fertilizer, 50% lower and 50% higher than the recommended fertilizer). Results showed that nitrogen use efficiency (NUE), nitrogen uptake efficiency (NUpE), nitrogen utilization efficiency (NUtE) and nitrogen efficiency ratio (NER) in wheat were significantly affected by crop rotation and nitrogen fertilizer and their interaction. The lowest and highest nitrogen use efficiencies were achieved in oilseed radish-wheat and fallow-wheat rotations. The greatest nitrogen use efficiency in oilseed radish-wheat was due to high utilization efficiency of nitrogen in the rotation. The greatest and smallest nitrogen utilization efficiencies (NUtE) were observed in oilseed radish-wheat and fallow-wheat rotations, respectively. Perko-wheat rotation with application of nitrogen at the conventional level for wheat brings about an acceptable economic yield and high nitrogen uptake and use efficiency and seems to be advantageous to other rotations.
- Published
- 2016
41. Explaining the low luminosity of Uranus: a self-consistent thermal and structural evolution
- Author
-
Allona Vazan, Ravit Helled, and University of Zurich
- Subjects
Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Convection ,Accretion (meteorology) ,530 Physics ,Uranus ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Radius ,Luminosity ,Atmosphere ,1912 Space and Planetary Science ,Space and Planetary Science ,Planet ,10231 Institute for Computational Science ,Physics::Space Physics ,Convective mixing ,3103 Astronomy and Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The low luminosity of Uranus is a long-standing challenge in planetary science. Simple adiabatic models are inconsistent with the measured luminosity, which indicates that Uranus is non-adiabatic because it has thermal boundary layers and/or conductive regions. A gradual composition distribution acts as a thermal boundary to suppress convection and slow down the internal cooling. Here we investigate whether composition gradients in the deep interior of Uranus can explain its low luminosity, the required composition gradient, and whether it is stable for convective mixing on a timescale of some billion years. We varied the primordial composition distribution and the initial energy budget of the planet, and chose the models that fit the currently measured properties (radius, luminosity, and moment of inertia) of Uranus. We present several alternative non-adiabatic internal structures that fit the Uranus measurements. We found that convective mixing is limited to the interior of Uranus, and a composition gradient is stable and sufficient to explain its current luminosity. As a result, the interior of Uranus might still be very hot, in spite of its low luminosity. The stable composition gradient also indicates that the current internal structure of Uranus is similar to its primordial structure. Moreover, we suggest that the initial energy content of Uranus cannot be greater than 20% of its formation (accretion) energy. We also find that an interior with a mixture of ice and rock, rather than separated ice and rock shells, is consistent with measurements, suggesting that Uranus might not be "differentiated". Our models can explain the luminosity of Uranus, and they are also consistent with its metal-rich atmosphere and with the predictions for the location where its magnetic field is generated., Comment: 10 pages, 7 figures, accepted for publication in A&A
- Published
- 2020
42. Proactive Simulation in Production Line Control
- Author
-
Jaroslav Znamenak, Pavel Vazan, and Martin Juhas
- Subjects
Production line ,Service (systems architecture) ,Computer science ,Process (engineering) ,Production control ,Control (management) ,Production (economics) ,Plan (drawing) ,Line (text file) ,Reliability engineering - Abstract
This paper deals with proposal of a proactive simulation model for a hybrid production system with an integrated MES used for safety, security, control, maintenance and service training with equipment similar to one utilized in a real industrial process. A proactive planning methodology can use information about real time changes in input data used for planning and determine a revised plan and line control. The proposed proactive procedure in this paper demonstrates a way to acquire data from an existing manufacturing process, which will be used to reach a production plan based on a combination of a simulation model and data acquired from MES. The revised control procedure will be send back to the MES to update the manufacturing process.
- Published
- 2018
43. Comparison of the Scalarization Approaches in Many-Objective Simulation-Based Optimization in Production System Control
- Author
-
Zuzana Cervenanska and Pavel Vazan
- Subjects
Mathematical optimization ,Simulation-based optimization ,Computer science ,Simulated annealing ,Brute-force search ,Production (economics) ,A priori and a posteriori ,Performance indicator ,Metaheuristic ,Multi-objective optimization - Abstract
Complex manufacturing systems control, involving contradictory production goals, is a challenge in spite of many multi-objective optimization decision-making strategies. In this article we demonstrate an application of the scalarization approach with a priori articulated preferences in the multiobjective optimization via discrete-event simulation in the field of the manufacturing product control. Especially, we focus on the effect of the used scalarizing multi-criteria function form combining all considering production goals using user-supplied weights. Four key performance indicators: costs per part unit, an average flow time, machines utilization and an amount of production for studied production system were finding by simulation in simulator Witness and optimized simultaneously under specific constraints. Metaheuristics like Thermoadaptive Simulated Annealing and Random Solutions and at last a brute force algorithm were used as optimization methods for finding global minimum of scalar functions generated by different methods of scalarization.
- Published
- 2018
44. Thermal evolution of rocky exoplanets with a graphite outer shell
- Author
-
Wim van Westrenen, Kaustubh Hakim, Carsten Dominik, Allona Vazan, Arie P. van den Berg, Dennis Höning, University of Zurich, and Low Energy Astrophysics (API, FNWI)
- Subjects
010504 meteorology & atmospheric sciences ,530 Physics ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,Mantle (geology) ,Physics::Geophysics ,chemistry.chemical_compound ,Thermal conductivity ,Mantle convection ,0103 physical sciences ,Thermal ,Physics::Atomic and Molecular Clusters ,Graphite ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Astronomy and Astrophysics ,Thermal conduction ,Silicate ,Exoplanet ,chemistry ,13. Climate action ,Space and Planetary Science ,10231 Institute for Computational Science ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The presence of rocky exoplanets with a large refractory carbon inventory is predicted by chemical evolution models of protoplanetary disks of stars with photospheric C/O >0.65, and by models studying the radial transport of refractory carbon. High-pressure high-temperature laboratory experiments show that most of the carbon in these exoplanets differentiates into a graphite outer shell. Our aim is to evaluate the effects of a graphite outer shell on the thermal evolution of rocky exoplanets containing a metallic core and a silicate mantle. We implement a parameterized model of mantle convection to determine the thermal evolution of rocky exoplanets with graphite layer thicknesses up to 1000 km. We find that, due to the high thermal conductivity of graphite, conduction is the dominant heat transport mechanism in a graphite layer for the long-term evolution (>200 Myr). The conductive graphite shell essentially behaves like a stagnant lid with a fixed thickness. Models of Kepler-37b (Mercury-size) and a Mars-sized exoplanet show that a planet with a graphite lid cools faster than a planet with a silicate lid, and a planet without a stagnant lid cools the fastest. A graphite lid needs to be approximately ten times thicker than a corresponding silicate lid in order to produce similar thermal evolution., 13 pages, 6 figures
- Published
- 2019
45. 3.1: Invited Paper: OLED Micro‐displays for VR/AR Applications
- Author
-
Amalkumar P. Ghosh, Qi Wang, Tariq Ali, Laurie Sziklas, Ihor Wacyk, Kerry Tice, Fridrich Vazan, and Ilyas I. Khayrullin
- Subjects
AMOLED ,Computer science ,Computer graphics (images) ,OLED ,High resolution ,Optical head-mounted display ,Augmented reality ,Virtual reality - Published
- 2019
46. Data integration and transformation proposal for big data analyses in automotive industry
- Author
-
Lukas Spendla, Lukas Hrcka, Pavel Vazan, Pavol Tanuska, and Michal Kebisek
- Subjects
business.industry ,Process (engineering) ,Computer science ,Big data ,Automotive industry ,computer.software_genre ,Data structure ,Manufacturing engineering ,Data set ,Transformation (function) ,Computer data storage ,business ,computer ,Data integration - Abstract
In our paper, we have focused on data integration and transformation process in the automotive industry, with emphasis on production data collected from the shop floor. One of the main issues addressed, is that the data are not stored in a central data storage, but in individual devices and systems, utilising different data formats. Our paper briefly describes the main tasks, required to collect production data into the big data storage and transform them into a unified data structure. We have also provided results of the initial analyses that were performed on the integrated and transformed data set.
- Published
- 2017
47. PTSD, Depression, Daily Stressors, and Treatment Pathways Among Urban Veterans
- Author
-
Andrew Golub, Alex S. Bennett, and Peter Vazan
- Subjects
medicine.medical_specialty ,education.field_of_study ,business.industry ,Population ,Poison control ,medicine.disease ,Mental health ,Suicide prevention ,Article ,humanities ,Occupational safety and health ,Substance abuse ,Injury prevention ,medicine ,Psychiatry ,education ,business ,health care economics and organizations ,General Psychology ,Social Sciences (miscellaneous) ,Depression (differential diagnoses) ,Clinical psychology - Abstract
Many veterans face various mental health challenges after separation. This study examines change over 14 months in mental health and related factors among 242 veterans returning to low-income predominantly minority sections of New York City. Mental health treatment provided more than reductions in symptoms of PTSD and depression; it also resulted in reductions in substance use disorders and daily stresses. However, many veterans not in treatment are experiencing combat-related concerns at subsyndromal levels. The findings highlight the need for low-threshold, community-based outreach programs for this population.
- Published
- 2015
48. Protective effect of melatonin against myocardial injury induced by epinephrine
- Author
-
Tatiana Ravingerova and Rastislav Vazan
- Subjects
Male ,medicine.medical_specialty ,Contraction (grammar) ,Epinephrine ,Physiology ,Stimulation ,Biochemistry ,Melatonin ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Cardiotoxicity ,business.industry ,Arrhythmias, Cardiac ,Heart ,General Medicine ,Free radical scavenger ,Rats ,Endocrinology ,Toxicity ,business ,Perfusion ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Epinephrine, in high doses, exhibits cardiotoxicity that is associated with excessive production of free radicals. Melatonin is antioxidant and free radical scavenger with cardioprotective properties. In our study, cardioprotective effects of melatonin against epinephrine cardiotoxicity were explored in the model of isolated rat heart. In the melatonin group, melatonin (50 μmol/l) was present in the perfusion solution during the whole experiment. In the control group, perfusion solution contained no melatonin. In both of the groups, after 30 min of initial perfusion, epinephrine was applied during 2 min directly into the heart and led to its strong stimulation. Changes in the heart function and arrhythmogenesis were evaluated before application of epinephrine and after the decline of its acute effects. No significant differences were observed during the initial perfusion. However, in the 15th and 20th minute after epinephrine application, indexes of ventricular contraction and relaxation were significantly higher in the melatonin group. Likewise, the values of the left ventricular developed pressure were significantly increased in this group in the 15th minute. These differences indicate better preservation of contraction and relaxation in the melatonin-treated group. Parameters of arrhythmogenesis-arrhythmia score, incidence and total duration of severe ventricular arrhythmias, were not significantly different between the experimental groups. However, their markedly lower average values in the melatonin-treated group suggest the reduction of electrical instability by melatonin. In conclusion, the obtained data confirm cardioprotective properties of melatonin and fill in the mosaic of information that can lead to the usage of melatonin as a therapeutic tool.
- Published
- 2015
49. Mathematical Approach to Security Risk Assessment
- Author
-
Marcel Abas, Michal Elias, Pavel Vazan, Michal Kebisek, Pavol Tanuska, Zuzana Sutova, Robert Vrabel, and Dusan Pavliak
- Subjects
Flammable liquid ,Engineering ,Article Subject ,business.industry ,lcsh:Mathematics ,General Mathematics ,General Engineering ,Risk management tools ,Nuclear power ,lcsh:QA1-939 ,Computer security ,computer.software_genre ,chemistry.chemical_compound ,Risk analysis (engineering) ,chemistry ,lcsh:TA1-2040 ,Hazardous waste ,Threat model ,lcsh:Engineering (General). Civil engineering (General) ,business ,Risk assessment ,computer ,Countermeasure (computer) ,Risk management - Abstract
The goal of this paper is to provide a mathematical threat modeling methodology and a threat risk assessment tool that may assist security consultants at assessing the security risks in their protected systems/plants, nuclear power plants and stores of hazardous substances: explosive atmospheres and flammable and combustible gases and liquids, and so forth, and at building an appropriate risk mitigation policy. The probability of a penetration into the protected objects is estimated by combining the probability of the penetration by overcoming the security barriers with a vulnerability model. On the basis of the topographical placement of the protected objects, their security features, and the probability of the penetration, we propose a model of risk mitigation and effective decision making.
- Published
- 2015
50. Design of Portal for Improvement Controlling Sales Channel
- Author
-
Pavel Vazan, Matus Peci, and Vladimir Surka
- Subjects
Engineering ,Process management ,business.industry ,Business process ,General Medicine ,Customer relationship management ,Appropriate technology ,computer.software_genre ,Software deployment ,Operating system ,Process control ,Web application ,Performance indicator ,business ,computer ,Communication channel - Abstract
This paper presents design of portal that improves controlling of sales channel at initial conditions. The customer needed to display key performance indicators on the portal and thus significantly improve the efficiency of business processes after the deployment of Microsoft Dynamics CRM 2011. The aim of this paper is to choose appropriate technology to create a portal and design possible architecture of solution. Microsoft Dynamics CRM 2011 with Web Application Microsoft SharePoint platform provide a solution for process control of business processes in company that is primarily offered like as the best solution. On the other hand, we found the possibility of open source content management system DotNetNuke, which meets customer's requirements and therefore, there is a possibility to reduce financial costs when selecting this system. Finally, we evaluated considered technologies, prepared more price variations of architecture and compared advantages and disadvantages of these variations.
- Published
- 2014
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