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1. Potentials on the conformally compactified Minkowski spacetime and their application to quark deconfinement

Author

Kirchbach, M. and Vallejo, J. A.

Subjects
Mathematical Physics, Quantum Physics, 81T40, 81U15, 81Q35
Abstract

We study a class of conformal metric deformations in the quasi-radial coordinate parameterizing the 3-sphere in the conformally compactified Minkowski spacetime $S^1\times S^3$. Prior to reduction of the associated Laplace-Beltrami operators to a Schr\"odinger form, a corresponding class of exactly solvable potentials (each one containing a scalar and a gradient term) is found. In particular, the scalar piece of these potentials can be exactly or quasi-exactly solvable, and among them we find the finite range confining trigonometric potentials of P\"oschl-Teller, Scarf and Rosen-Morse. As an application of the results developed in the paper, the large compactification radius limit of the interaction described by some of these potentials is studied, and this regime is shown to be relevant to a quantum mechanical quark deconfinement mechanism., Comment: Small typos corrected, a new example and a couple of references added

Published
2023
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2. Wave functions of the Hydrogen atom in the momentum representation

Author

Kirchbach, M. and Vallejo, J. A.

Subjects
Quantum Physics, Mathematical Physics, 81V45, 44A15, 33C47
Abstract

We construct the integral transform passing from the space representation to the momentum representation for the Hydrogen atom using polar spherical coordinates. The resulting radial wave functions are explicitly given in terms of complex finite expansions of Gegenbauer functions of the first and second kind, or in terms of (elementary) trigonometric functions. We show their symmetry under the $SO(4)$ group, and their equivalence with those of Lombardi and Oglivie., Comment: Revised version, according to the referees' suggestions. Includes new figures

Published
2022
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3. The Conformal-Symmetry--Color-Neutrality Connection in Strong Interaction

Author

Kirchbach, M., Popov, T., and Vallejo, J. -A.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Theory
Abstract

The color neutrality of hadrons is interpreted as an expression of conformal symmetry of strong interaction, the latter being signaled through the detected "walking" at low transferred momenta, $\lim_{Q^2\to 0}\alpha_s(Q^2)/\pi\to 1 $, of the strong coupling toward a fixed value ($\alpha_s $ "freezing" ). The fact is that conformal symmetry admits quarks and gluons to reside on the compactified $AdS_5$ boundary, whose topology is $S^1\times S^3$, a closed space that can bear exclusively color-charge neutral configurations, precisely as required by color confinement. The compactification radius, once employed as a second scale alongside with $\Lambda_{QCD}$, provides for an $\alpha_s(Q^2) $ "freezing" mechanism in the infrared regime of QCD, thus making the conformal-symmetry--color-neutrality connection at low energies evident. In this way, perturbative descriptions of processes in the infrared could acquire meaning. In consequence, it becomes possible to address QCD by quantum mechanics in terms of a conformal wave operator equation, which leads to an efficient description of a wide range of, Comment: Contribution to the proceedings of the XIV. Int. Workshop Lie Theory and its Applications in Physics, 20-26 June 2021, Sofia, Bulgaria

Published
2022

5. Color confinement at the boundary of the conformally compactified $\mathrm{AdS}_5$

Author

Kirchbach, M., Popov, T., and Vallejo, J. A.

Subjects
High Energy Physics - Theory, Mathematical Physics, Mathematics - Differential Geometry, 81V05, 53C18, 81R15
Abstract

The topology of closed manifolds forces interacting charges to appear in pairs. We take advantage of this property in the setting of the conformal boundary of $\mathrm{AdS}_5$ spacetime, topologically equivalent to the closed manifold $S^1\times S^3$, by considering the coupling of two massless opposite charges on it. Taking the interaction potential as the analog of Coulomb interaction (derived from a fundamental solution of the $S^3$ Laplace-Beltrami operator), a conformal $S^1\times S^3$ metric deformation is proposed, such that free motion on the deformed metric is equivalent to motion on the round metric in the presence of the interaction potential. We give explicit expressions for the generators of the conformal algebra in the representation induced by the metric deformation. By identifying the charge as the color degree of freedom in QCD, and the two charges system as a quark--anti-quark system, we argue that the associated conformal wave operator equation could provide a realistic quantum mechanical description of the simplest QCD system, the mesons. Finally, we discuss the possibility of employing the compactification radius, $R$, as another scale along $\Lambda_{QCD}$, by means of which, upon reparametrizing $Q^2c^2$ as $\left( Q^2c^2 +\hbar^2 c^2/R^2\right)$, a pertubative treatment of processes in the infrared could be approached., Comment: Minor changes to match the published version

Published
2021
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6. Detection of graphene's divergent orbital diamagnetism at the Dirac point

Author

Vallejo, J., Wu, N. J., Fermon, C., Pannetier-Lecoeur, M., Wakamura, T., Watanabe, K., Tanigushi, T., Pellegrin, T., Bernard, A., Daddinounou, S., Bouchiat, V., Guéron, S., Ferrier, M., Montambaux, G., and Bouchiat, H.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

The electronic properties of graphene have been intensively investigated over the last decade, and signatures of the remarkable features of its linear Dirac spectrum have been displayed using transport and spectroscopy experiments. In contrast, the orbital magnetism of graphene, which is one of the most fundamental signature of the characteristic Berry phase of graphene's electronic wave functions, has not yet been measured in a single flake. In particular, the striking prediction of a divergent diamagnetic response at zero doping calls for an experimental test. Using a highly sensitive Giant Magnetoresistance sensor (GMR) we have measured the gate voltage-dependent magnetization of a single graphene monolayer encapsulated between boron nitride crystals. The signal exhibits a diamagnetic peak at the Dirac point whose magnetic field and temperature dependences agree with theoretical predictions starting from the work of Mc Clure \cite{McClure1956}. Our measurements open a new field of investigation of orbital currents in graphene and 2D topological materials, offering a new means to monitor Berry phase singularities and explore correlated states generated by combined effects of Coulomb interactions, strain or moir\'e potentials., Comment: 6 pages 5 figures and supplemental material

Published
2020
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7. Formation of dust filaments in the diffuse envelopes of molecular clouds

Author

Beitia-Antero, L., de Castro, A. I. Gómez, and Vallejo, J. C.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

The path to understanding star formation processes begins with the study of the formation of molecular clouds. The outskirts of these clouds are characterized by low column densities that allow the penetration of ultraviolet radiation, resulting in a non-negligible ionization fraction and the charging of the small dust grains that are mixed with the gas; this diffuse phase is then coupled to the ambient magnetic field. Despite the general assumption that dust and gas are tightly correlated, several observational and theoretical studies have reported variations in the dust-to-gas ratio toward diffuse and cold clouds. In this work, we present the implementation of a new charged particles module for analyzing the dust dynamics in molecular cloud envelopes. We study the evolution of a single population of small charged grains (0.05 $\mu$m) in the turbulent, magnetized molecular cloud envelope using this module. We show that variations in the dust-to-gas ratio arise due to the coupling of the grains with the magnetic field, forming elongated dust structures decoupled from the gas. This emphasizes the importance of considering the dynamics of charged dust when simulating the different phases of the interstellar medium, especially for star formation studies., Comment: 16 pages, 14 figures, accepted for publication in ApJ

Published
2020
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8. Effect of the Factor XIa Inhibitor Asundexian According to Baseline Infarct Pattern and on MRI Covert Infarct Outcomes

Author

Smith, Eric E., Shoamanesh, Ashkan, Xu, Lizhen, Heenan, Laura, Saad, Feryal, Colorado, Pablo, Chen, Chih-Hao, Lemmens, Robin, De Marchis, Gian Marco, Caso, Valeria, Masjuan, Jaime, Hirano, Teruyuki, Milanov, Ivan, Campbell, Bruce C.V., Mas, Jean-Louis, Connolly, Stuart J., Mundl, Hardi, Hart, Robert G., Bailey, P., Kleinig, T., Cordato, D., Choi, P., Garcia-Esperon, C., Chew, A., Cloud, G., Stanislaus, V., Krause, M., Priglinger, M., Grimley, R., Ghia, D., Sahathevan, R., Brown, H., Kwan, C., Devlin, M., Greisenegger, S., Bonelli-Nauer, S., Rath, J., Langer, A., Marko, M., Ferrari, J., Bernegger, A., Baumgartinger, M., Vigl, M., Krebs, S., Lang, W., Knoflach, M., Dejakum, B., Kiechl, S., Töll, T., Domig, L., Mutzenbach, J.S., Ganser, B., Hecker, C., Rösler, C., Bubel, N., Pikija, S., Zellner, T., Leitner, U., Berger, O., Surböck, B., Beirer, S., Staykov, D., Schrammel, D., Halilovic, A., Frattner, M., Barmherzigen, D., Lampl, C., Höfer, C., Nagl, S., Bocksrucker, C., Demeestere, J., Desfontaines, P., Ciobanu, C., De Pauw, A., Terwecoren, A., Hasenbroekx, M.C., Clement, F., De Klippel, N., Soors, P., Hermans, S., De Raedt, S., Vandervorst, F., Seynaeve, L., Fockaert, N., Smet, S., Rutgers, M., Del Gaudio, N., Paindeville, P., Staikov, I., Simeonova, A., Stoyanova, I., Cholakova, M., Mihnev, N., Petrova, T., Koralova, A., Dimov, D., Kuzev, Y., Danovska, M., Marinova, D., Marinova-Trifonova, D., Ovcharova, E., Mladenovski, I., Yanakieva, M., Stoev, P., Dimitrova, M., Todorova-Georgieva, S., Haralanov, L., Milkov, B., Solakov, D., Petkova, N., Ignatova-Valkova, V., Karabinov, V., Marinova, V., Miteva, Y., Andonova, V., Kasabova, D., Kostadinova, E., Shopova-Vrabcheva, Y., Gatev, D., Semova, D., Halil, E., Kaprelyan, A., Ivanov, B., Panov, G., Grudkova, M., Syuleyman, N., Kalpachki, R., Alexiev, F., Ivanova, I., Kancheva, K., Sakelarova, T., Maslarov, D., Drenska, D., Georgiev, V., Petrova, K., Petrova, N., Ivanova, I., Semerdjieva, N., Zhelyazkov, P., Spasova-Markova, S., Dong, X., Wang, D., Wang, S., Huang, W., Zhao, H., Wang, C., Jie, L., Xinyang, Y., Ping, Z., Dong, Q., Wang, Y., Fuling, Y., Yue, W., Liu, R., Yang, Y., Stetkarova, I., Mikulenka, P., Vasko, P., Peisker, T., Bar, M., Roubec, M., Mikulik, R., Cabukova, M., Vinklarek, J., Kovar, M., Pansky, M., Mencl, P., Skoda, O., Carek, M., Pernicka, M., Skodova, M., Geier, P., Cepkova, J., Drlik, J., Prax, T., Herzig, R., Krajickova, D., Vitkova, E., Haluskova, S., Vaclavik, D., Martinkova, J., Blejcharova, K., Tkacova, M., Pavlik, O., Nevšímalová, M., Rosol, J., Nevsimalova, M., Hruby, R., Iversen, H., Andersen, A.V., Rahimi, D., Christensen, H., Grundtvig, J., Hjort, N., Andersen, G., Sandal, B., Stilund, M., Modrau, B., Strade, A., Porobic, M., Andersen, S.D., Kruuse, C., Ölmestig, J., Kolmos, M., Parvez, A., Christensen, T., Stokholm, J., Jensen, H.B., Putaala, J., Strbian, D., Sibolt, G., Tiainen, M., Martinez-Majander, N., Curtze, S., Raty, S., Kraemer, Y., Roine, R., Aivo, J., Ruuskanen, J., Ylikotila, P., Roine, S., Hallikainen, M., Jakala, P., Kurl, S., Julkunen, V., Sibon, I., Olindo, S., Richard, S., Larrue, V., Gollion, C., Catala, H., Henon, H., Lucie, D.S., Nelly, D., Calvet, D., Malbranque, A., Mazé, B., Barbieux-Ghitu, C., Rosso, C., Samson, Y., Vannier, S., Moulin, T., Bonnet, L., Reiner, P., Buffon, F., Denier, C., Amri, K., Legris, N., Chassin, O., Selli, N., Mariana, S., Berrouschot, J., Stoll, A., Klunk, D., Keilitz, J., Neustadt, M., Zerrenner, S., Veltkamp, R., Hajjar, K., Heeger, A., Winezki, E., Apel, L., Pompsch, M., Mueller, P., Rappard, P., Auer, R., Ringleb, P.A., Berberich, A., Heyse, M., Mundiyanapurath, S., Reiff, T., Poli, S., Gomez-Exposito, A., Mengel, A., Tünnerhoff, J., Adeyemi, K., Poli, K., Kusch, V., Pelz, J., Michalski, D., Wartenberg, K., Althaus, K., Tavares, F., Mueller, S., Soda, H., Rascher, A., Hiermann, E., Weinhardt, R., Weissenborn, K., Leotescu, A., Grosse, G., Worthmann, H., Ernst, J., Gabriel, M., Schuppner, R., Schäfer, J.H., Charisse, D., Gruber, K., Kurka, N., Reitz, S.C., Pfeilschifter, W., Lee, J.I., Gliem, M., Moll, M., Steiner, T., Segura, L., Szegedi, N., Barandi, D., Uhrinakova, L., Czencz, M., Pasztor, M., Gyuker, N., Bartha, N.E., May, Z., Simony, Z., Szasz, G., Kakuk, I., Pető, N., Panczel, G.F., Olah, A., Racz, O., Balla, T., Horvath, B., Tuba, K., Czinderi, V., Klivenyi, P., Annus, A., Hertelendy, P., Szapary, L., Bosnyak, E., Kalmar, P., Karadi, Z., Cziba, L., Olah, L., Berki, A., Hudak, L., Kozák, M., Babel, S., Nemeth, L., Molnár, B., Simon, Z., Roveri, L., Cerri, F., Giacalone, G., Zini, A., Mauro, G., Asioli, G.M., Forlivesi, S., Arnone, G., Fiaccadori, A., Maria Fontana Francesca, E., Allegra, G., Mosconi, M.G., Longoni, M., Terlizzi, R., Paolucci, M., Tassi, R., Franci, B., Lucani, B., Domenichelli, C., Paoletti, D., Acampa, M., Zedde, M.L., Pezzella, F.R., Mangiardi, M., Galizia, P., Anticoli, S., Scalise, S., Lattanzi, S., Norata, D., Cannuccia, M., Cavallini, A., Federica, F., Denaro, M.F., Tosi, P., Sonoda, K., Kawajiri, M., Kusano, Y., Haraguchi, K., Kawano, H., Terasaki, T., Kaneko, C., Murase, S., Kumagai, M., Murai, N., Miyazaki, Y., Mori, T., Hatano, T., Kawanishi, M., Ochiai, J., Ishihara, S., Uehara, T., Yasaka, M., Nakagawa, H., Makino, M., Yonehara, T., Fukushima, Y., Hirotsune, N., Sakai, N., Yamasaki, M., Coutinho, J., Wouters, A., den Hertog, H., Zwartbol, R., Beumer, D., Kerklaan, J., Hilkens, P., Schreuder, T., Propper, D., Slowik, A., Wlodarczyk, E., Wrona, P., Pulyk, R., Lasek-Bal, A., Kosarz-Lanczek, K., Puz, P., Bilik, M., Magielska, A., Zamiela – Żółciak, A., Ochocinska, L., Bahdasaryan, S., Stępień, A., Dębiec, A., Joanna, K., Pawel, M., Jacek, S., Daniel, P., Marta, S., Rejdak, K., Wojczal, J., Luchowski, P., Fryze, W., Wisniewska, A., Krzyzanowska, M., Skowron, P., Wolosz, A., Galan, A., Grzymala, K., Krajewska, M., Nowak, R., Kłos, M., Cruz, V., Castro, P., Ferro, J., Canhão, P., Gouveia, R., Inácio, N., Rodrigues, M., Rachão, A., Ionel, C., Pereira, L., Viana-Baptista, M., Machado, C., Fernandes, C., Sargento, J., Inácio, N., Timchenko, L., Mironova, J., Zhadan, O., Torgashova, A., Bazhenova, O., Barashenkova, M., Kireeva, M., Romadina, N., Stepanova, I., Lenskaya, L., Lukinykh, L., Vorontsova, T., Agafina, A., Fedorova, A., Yashina, A., Alasheev, A., Smolkin, A., Prazdnichkova, E., Lutskovich, O., Gonysheva, Y., Mordvintseva, E., Nechaev, A., Martynova, E., Fedoraeva, N., Vishnyakova, T., Popov, D., Merzliakova, A., Margarita, K., Rechkalova, L., Ilyina, A., Kurenkova, N., Barbarash, O., Bazdyrev, E., Zvereva, T., Hromova, A., Morkvenas, A., Postnikova, E., Kovalenko, G., Taran, I., Pavlov, L., Ott, M., Chernitsova, N., Vodopyanova, N., Drozdova, E., Korebo, E., Lobanova, M., Lazareva, N., Snegova, N., Nikolaeva, O., Kolesnikov, Y., Kosheleva, Y., Krastev, G., Tomasova, K., Danis, M., Mako, M., Jankovicova, Z., Stevkova, Z., Kovacik, M., Kubikova, T., Jarosova, A., Serdahely, V., Cilingova, I., Pribulova, I., Sedlak, J., Slebodova, K., Paldaufova, M., Risnovsky, R., Berndtova, B., Urbanova, I., Junas, R., Karapetian, S., Gurcik, L., Vantrobova, A., Verbovsky, F., Vanacka, K., Ferenc, M., Galik, P., Bucakova, S., Ferencova, M., Kubalova, P., Boksanska, Z., Zacharova, E., Mahundi, E., Judita, H., Bachnak, M., Turcani, P., Kvasnicova Kamenska, A., Jurik, M., Vestenicka, V., Kycina, M., Sagatova, E., Dvorak, M., Hlubekova, A., Kucera, C., Gernath, L., Ferenc, M., Frimmelova, P., Slebodnikova, J., Aksteinerova, N., Horny, V., Gregova, Z., Segura, T., Romero, C., Ayo, O., Masjuan Vallejo, J., Cruz, A., De felipe, A, Matute, M.C., Garcia, S., Tembl Ferrairo, J., Vielba, I., Morales Caba, L., Molina, C., Garcia-Tornel García-Camba, Á., Requena Ruiz, M., Noelia, R., Rodriguez-Yañez, M., Rodriguez Castro, E., Lopez, I., Santamaria, M., Arias, S., Purroy García, F., Vázquez Justes, D., Mauri Capdevila, G., Vicente Pascual, M., Martí Fabregas, J., Camps Renom, P., Rodríguez Campello, A., Giralt, E., Krupinski, J., Molina, J., Trillo Senin, C. Ramos Martin, S., De La Fuente Sanz, E., Moniche, F., Manuel, M.R., Pardo, B., Martínez, I., Hernández Pérez, M., Arenillas Lara, J.F., De Lera, M., Egido, J.A., Gomez Escalonilla, C., Guillan, M., Martinez, J., Lindgren, A., Andsberg, G., Wictor, L., Leonidou, M., Stenman, M., Dalberg, N., Laska, A.C., Grünfeldt, A., Lundström, A., Nadzjafov, E., Rooth, E., Dalenbring, I., Sandén, P., Johansson, E., Thomas, G., Zietz, A.V., Rudin, S., Dittrich, T.D., Lilian, K., Kägi, G., Vehoff, J., Arnold, M., Scutelnic, A., Clénin, L., Beyeler, M., Madlaine, M., Maamari, B., Siepen, B., Vynckier, J., Tarnutzer, A., Bertschi, D., Luciani, M., Cereda, C., Maulucci, F., Bianco, G., Shairin, S., Pihan, H.A., Salmen, S., Quinn, T., McAlpine, C., Wright, F., Kalladka, D., Taylor, E., Sohaa, J., Brown, Z., Dawson, J., Cameron, A., Muir, S., Dima, S., Khan, U., Zhang, L., Warburton, E., Chatterjee, K., Nallasivan, A., Curran, D., Haider, S., Ghani, U., Kenton, A., Dallol, B., Mirza, M., Menezes, B., Davies, R., Robinson, T.G., Manning, L., Sztriha, L., Phinney, T., Sethi, P., Altafullah, I., Sharaf, A., Ostrander, M., Renati, S., Burgin, W.S., Olds, K., Delio, P., Malek, A., Dissin, J., Khatri, P., Flaherty, M., Demel, S., and Dofitas, S.

Published
2024
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9. Characteristics of Inhaler Technique in COPD Patients in a Specialized Center in Armenia, Colombia: A Cross-Sectional Study

Author

Montes Cardona JA, Hincapié Erira DA, Nati-Castillo HA, Sánchez-Vallejo J, and Izquierdo-Condoy JS

Subjects
pulmonary disease, chronic obstructive, administration, inhalation, medication errors., Medicine (General), R5-920
Abstract

Jorge A Montes Cardona,1 Diego A Hincapié Erira,1 Humberto Alejandro Nati-Castillo,1 Jaime Sánchez-Vallejo,2 Juan S Izquierdo-Condoy3 1Faculty of Health Sciences, Universidad del Quindío, Armenia, Colombia; 2Pneumology Service, IPS Neumovida, Armenia, Colombia; 3One Health Research Group, Universidad de las Américas, Quito, EcuadorCorrespondence: Juan S Izquierdo-Condoy, OneHealth Global Research Group, Universidad de las Américas, Quito, Ecuador Calle de los Colimes y Avenida De los Granados, Quito, 170137, Tel +593992561230, Email juan1izquierdo11@gmail.comPurpose: The aim of this research was to evaluate the technique of using inhaled drugs in patients with a confirmed history of COPD and describe errors in inhaler technique.Patients and Methods: Descriptive cross-sectional study was conducted in patients with a history of COPD using inhalation therapy, attending pulmonology consultation between August 2020 and April 2021 in Armenia, Colombia. A non-probabilistic sample of 80 adult participants was calculated, and the inhalation technique was evaluated (depending on the device used) using a scale validated for Colombia. Descriptive analysis of the qualitative variables was performed using frequencies and percentages. The Chi-Square test and Fisher’s exact test (in corresponding cases) were used to look for association relationships between categorical variables.Results: A total of 80 participants were evaluated, of which 66.3% (n = 53) were male, and 32.5% were older than 80 years. Clinically, 30.0% (n = 24) were classified as Modified Medical Research Council Dyspnea Scale (mMRC) grade 3, and 51.2% (n = 41) had at least one exacerbation per year. The main comorbidity was hypertension (40.3%). Pressurized metered-dose inhalers with spacer were the most used device at 22.7% (n = 39). Incorrect technique (at least one error in the steps of the inhalation technique used) was found in 48.7%. The most frequent error among all the techniques was the failure to perform pre-inspiratory exhalation. No significant differences were observed between the development of the technique and the characteristics of the participants.Conclusion: Nearly half of the patients who use inhalation devices make errors in the technique. Patient education and training of healthcare personnel represent a fundamental pillar in mitigating the incorrect use of these devices.Keywords: pulmonary disease, chronic obstructive, administration, inhalation, medication errors

Published
2023

12. Acausal quantum theory for non-Archimedean scalar fields

Author

Mendoza-Martínez, M. L., Vallejo, J. A., and Zúñiga-Galindo, W. A.

Subjects
High Energy Physics - Theory, Mathematical Physics, Mathematics - Functional Analysis, 81T05, 11S40, 35S05
Abstract

We construct a family of quantum scalar fields over a $p-$adic spacetime which satisfy $p-$adic analogues of the G\aa rding--Wightman axioms. Most of the axioms can be formulated the same way in both, the Archimedean and non-Archimedean frameworks; however, the axioms depending on the ordering of the background field must be reformulated, reflecting the acausality of $p-$adic spacetime. The $p-$adic scalar fields satisfy certain $p-$adic Klein-Gordon pseudo-differential equations. The second quantization of the solutions of these Klein-Gordon equations corresponds exactly to the scalar fields introduced here., Comment: Third version, with some typos corrected. Accepted for publication in Reviews in Mathematical Physics (2019). Includes referee's suggestions

Published
2018
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13. The World Space Observatory Ultraviolet (WSO-UV), as a bridge to future UV astronomy

Author

Shustov, B., de Castro, A. I. G'omez, Sachkov, M., Vallejo, J. C., Marcos-Arenal, P., Kanev, E., Savanov, I., Shugarov, A., and Sichevskii, S.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The ultraviolet (UV) astronomy is a very demanded branch of space astronomy. Many dozens of short-term UV-experiments in space, as well as long-term observatories, have brought a very important knowledge on the physics and chemistry of the Universe during the last decades. Unfortunately, no large UV-observatories are planned to be launched by most of space agencies in the coming 10 -- 15 years. Conversely, the large UVOIR observatories of the future will appear not earlier than in 2030s. This paper briefly describes the projects that have been proposed by various groups. We conclude that the World Space Observatory -- Ultraviolet (WSO-UV) will be the only 2-m class UV telescope with capabilities similar to those of the HST for the next decade. The WSO-UV has been described in detail in previous publications, and this paper updates the main characteristics of its instruments and the current state of the whole project. It also addresses the major science topics that have been included in the core program of the WSO-UV, making this core program very relevant to the current state of the UV-astronomy. Finally, we also present here the ground segment architecture that will implement this program., Comment: International symposium "Ultraviolet Sky Surveys: the need and the means", 10-14 July 2017, Tel Aviv University, Israel

Published
2018
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22. WSO–UV Project: New Touches

Author

Shustov, B. M., Sachkov, M. E., Sichevsky, S. G., Arkhangelsky, R. N., Beitia-Antero, L., Bisikalo, D. V., Bogachev, S. A., Buslaeva, A. I., Vallejo, J. C., Gomez de Castro, A.I., Grigorovich, S. V., Iosipenko, S. V., Kanev, E. N., Canet, A., Korablev, O. I., Kuzin, S. V., Moisheev, A. A., Cazalla, I. Prada, Tavrov, A. V., de la Fuente Marcos, R., Shakhanov, A. E., Shmagin, V. E., Shostak, S. V., Shugarov, A. S., and Yañez Gestoso, F. J.

Published
2021
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23. Engraftment after autologous hematopoietic stem cell transplantation in patients mobilized with Plerixafor: A retrospective, multicenter study of a large series of patients

Author

Antelo, M. Luisa, Altuna, Ane, Gimeno, J. José, Ferreiro, J. Javier, Amunárriz, Cristina, Mateos, J. José, Zalba, Saioa, Alkorta, Aitziber, Rifón, José, Arroyo, J. Luis, Uresandi, Amaia, Moreno, J. Antonio, Nájera, M. Josefa, Pinzón, Sergio, García, Alejandro, and Vallejo, J. Carlos

Published
2021
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33. Lie algebroids generated by cohomology operators

Author

García-Beltrán, D., Vallejo, J. A., and Vorobiev, Yu.

Subjects
Mathematics - Differential Geometry, Mathematical Physics, 58F15 (Primary), 58F17, 53C35 (Secondary)
Abstract

By studying the Fr\"olicher-Nijenhuis decomposition of cohomology operators (that is, derivations $D$ of the exterior algebra $\Omega (M)$ with $\mathbb{Z}-$degree $1$ and $D^2=0$), we describe new examples of Lie algebroid structures on the tangent bundle $TM$ (and its complexification $T^{\mathbb{C}}M$) constructed from pre-existing geometric ones such as foliations, complex, product or tangent structures. We also describe a class of Lie algebroids on tangent bundles associated to idempotent endomorphisms with nontrivial Nijenhuis torsion., Comment: Second version

Published
2014
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34. Higher order corrections to adiabatic invariants of generalized slow-fast Hamiltonian systems

Author

Avendaño-Camacho, M., Vallejo, J. A., and Vorobiev, Yu.

Subjects
Mathematics - Dynamical Systems, Mathematical Physics, Nonlinear Sciences - Exactly Solvable and Integrable Systems, 70H11, 70H09, 53D22
Abstract

We present a coordinate-free approach for constructing approximate first integrals of generalized slow-fast Hamiltonian systems, based on the global averaging method on parameter-dependent phase spaces with $\mathbb{S}^1 -$symmetry. Explicit global formulas for approximate second-order first integrals are derived. As examples, we analyze the case quadratic in the fast variables (in particular, the elastic pendulum), and the charged particle in a slowly-varying magnetic field., Comment: First version

Published
2013
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35. Quillen superconnections and connections on supermanifolds

Author

Beltrán, J. V., Monterde, J., and Vallejo, J. A.

Subjects
Mathematics - Differential Geometry, High Energy Physics - Theory, Mathematical Physics, 53C07, 58C50, 81T13
Abstract

Given a supervector bundle $E = E_0\oplus E_1 \to M$, we exhibit a parametrization of Quillen superconnections on $E$ by graded connections on the Cartan-Koszul supermanifold $(M;\Omega (M))$. The relation between the curvatures of both kind of connections, and their associated Chern classes, is discussed in detail. In particular, we find that Chern classes for graded vector bundles on split supermanifolds can be computed through the associated Quillen superconnections., Comment: First version

Published
2013
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36. A simple global representation for second-order normal forms of Hamiltonian systems relative to periodic flows

Author

Avendaño-Camacho, M., Vallejo, J. A., and Vorobjev, Yu.

Subjects
Mathematical Physics, Mathematics - Differential Geometry, Mathematics - Dynamical Systems, Nonlinear Sciences - Exactly Solvable and Integrable Systems, 53D17, 53-04 (Primary) 70F15 (Secondary)
Abstract

We study the determination of the second-order normal form for perturbed Hamiltonians $H_{\epsilon}=H_0 +\epsilon H_1 +\frac{\epsilon^2}{2} H_2$, relative to the periodic flow of the unperturbed Hamiltonian $H_0$. The formalism presented here is global, and can be easily implemented in any CAS. We illustrate it by means of two examples: the H\'enon-Heiles and the elastic pendulum Hamiltonians., Comment: Third version. A more detailed mathematical treatment, the computational part has been relegated to the documentation of the package, which can be downloaded from http://galia.fc.uaslp.mx/~jvallejo/pdynamics.zip

Published
2013
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37. Chaotic dynamics with Maxima

Author

Morante, A. and Vallejo, J. A.

Subjects
Nonlinear Sciences - Chaotic Dynamics, Mathematical Physics, Mathematics - Dynamical Systems, 37D45, 70-04, 70Kxx
Abstract

We present an introduction to the study of chaos in discrete and continuous dynamical systems using the CAS Maxima. These notes are intended to cover the standard topics and techniques: discrete and continuous logistic equation to model growth population, staircase plots, bifurcation diagrams and chaos transition, nonlinear continuous dynamics (Lorentz system and Duffing oscillator), Lyapunov exponents, Poincar\'e sections, fractal dimension and strange attractors. The distinctive feature here is the use of free software with just one ingredient: the CAS Maxima. It is cross-platform and have extensive on-line documentation., Comment: To appear in Electronic Journal of Mathematics and Technology

Published
2013

42. The principle of stationary action in the calculus of variations

Author

López, E., Molgado, A., and Vallejo, J. A.

Subjects
Mathematical Physics, Mathematics - Optimization and Control, 49K15, 49S05, 34K11
Abstract

We review some techniques from non-linear analysis in order to investigate critical paths for the action functional in the calculus of variations applied to physics. Previous attempts to analyse when these are minima ex- ist, but mainly based on physical reasoning and only for a restricted class of models. Our main intention in this regard is to develop precise mathematical conditions for critical paths to be minimum solutions in a variety of situations. Our claim is that, with a few techniques, a systematic analysis (including the domain for which critical points are genuine minima) of non-trivial models is possible. We present specific models arising in modern physical theories in order to make clear the ideas here exposed., Comment: Corrected version (minor typos and added acknowledgements). To appear in Communications in Mathematics, vol 2 2012

Published
2012

43. Efficacy and safety of cemiplimab in the treatment of advanced cutaneous squamous cell carcinoma: A multicentre real‐world retrospective study from Spain and systematic review of the published data

Author

Cañueto, J., primary, Muñoz‐Couselo, E., additional, Cardona‐Machado, C., additional, Becerril‐Andrés, S., additional, Martín‐Vallejo, J., additional, Serra‐Guillén, C., additional, Soria, A., additional, Serrano‐Domingo, J. J., additional, Ortiz‐Velez, C., additional, Lostes, J., additional, García‐Castaño, A., additional, Puig, S., additional, Fernández de Misa, R., additional, Medina, J., additional, Aguado, C., additional, Ayala de Miguel, P., additional, Navarro‐Nava, I., additional, Masferrer, E., additional, Delgado, M., additional, Bellido‐Hernández, L., additional, and Sanmartin, O., additional

Published
2024
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45. Clifford Algebra of the Vector Space of Conics for decision boundary Hyperplanes in m-Euclidean Space

Author

Nieto, Isidro B. and Vallejo, J. Refugio

Subjects
Computer Science - Neural and Evolutionary Computing, Computer Science - Computational Geometry, I.5.1, I.5.2, I.2.6, I.3.5
Abstract

In this paper we embed $m$-dimensional Euclidean space in the geometric algebra $Cl_m $ to extend the operators of incidence in ${R^m}$ to operators of incidence in the geometric algebra to generalize the notion of separator to a decision boundary hyperconic in the Clifford algebra of hyperconic sections denoted as ${Cl}({Co}_{2})$. This allows us to extend the concept of a linear perceptron or the spherical perceptron in conformal geometry and introduce the more general conic perceptron, namely the {elliptical perceptron}. Using Clifford duality a vector orthogonal to the decision boundary hyperplane is determined. Experimental results are shown in 2-dimensional Euclidean space where we separate data that are naturally separated by some typical plane conic separators by this procedure. This procedure is more general in the sense that it is independent of the dimension of the input data and hence we can speak of the hyperconic elliptic perceptron., Comment: 12 pages, 2 figures, 1 table

Published
2007

47. Prognostic factors and analysis of mortality due to brain haemorrhages associated with vitamin K antagonist oral anticoagulants. Results from the TAC Registry

Author

Zapata-Wainberg, G., Quintas, S., Ximénez-Carrillo Rico, A., Benavente Fernández, L., Masjuan Vallejo, J., Gállego Culleré, J., Freijó Guerrero, M. del M., Egido, J., Gómez Sánchez, J.C., Martínez Domeño, A., Purroy, F., Vives Pastor, B., Rodríguez Yáñez, M., and Vivancos, J.

Published
2018
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48. Factores pronósticos y análisis de la mortalidad de las hemorragias cerebrales asociadas a anticoagulantes orales antagonistas de la vitamina K. Resultados del Estudio TAC Registry

Author

Zapata-Wainberg, G., Quintas, S., Ximénez-Carrillo Rico, A., Benavente Fernández, L., Masjuan Vallejo, J., Gállego Culleré, J., Freijó Guerrero, M. del M., Egido, J., Gómez Sánchez, J.C., Martínez Domeño, A., Purroy, F., Vives Pastor, B., Rodríguez Yáñez, M., and Vivancos, J.

Published
2018
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49. Generating Operators of the Krasil'shchik-Schouten bracket

Author

Vallejo, J. A.

Subjects
Mathematical Physics, 13Nxx, 53Dxx (Primary) 14F05, 53DA7 (Secondary)
Abstract

It is proved that given a divergence operator on the structural sheaf of graded commutative algebras of a supermanifold, it is possible to construct a generating operator for the Krashil'shchik-Schouten bracket. This is a particular case of the construction of generating operators for a special class of bigraded Gerstenhaber algebras. Also, some comments on the generalization of these results to the context of $n-$graded Jacobi algebras are included.

Published
2003
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