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Search Results: 1 - 10 of 478840 matches for " Nicolás Pérez-Hidalgo "
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First record of the adventive oriental aphid Schizaphis piricola (Matsumura, 1917) (Hemiptera, Aphididae) in Europe
Nicolás Pérez-Hidalgo,ángel Umaran,M. Pilar Mier-Durante
ZooKeys , 2011, DOI: 10.3897/zookeys.89.903
Abstract: The oriental aphid Schizaphis piricola Matsumura, is recorded for the first time in Europe, on the ornamental pear tree Pyrus calleryana in landscaped areas in Madrid (Spain). Data on the morphology of the primary host (apterous and alate fundatrigeniae and fundatrices), and their biology and distribution are given. The keys for identifying species of Schizaphis (Schizaphis) in the Iberian Peninsula are updated. Two species of aphids are also recorded for the first time on Pyrus calleryana: S. piricola and Aphis pomi.
A new species of Rhopalosiphum (Hemiptera, Aphididae) on Chusquea tomentosa (Poaceae, Bambusoideae) from Costa Rica
Nicolás Pérez-Hidalgo,David Martínez-Torres,Jorge Mariano Collantes-Alegre,William Villalobos Muller
ZooKeys , 2012, DOI: 10.3897/zookeys.166.2387
Abstract: The new species Rhopalosiphum chusqueae Pérez Hidalgo & Villalobos Muller, is described from apterous viviparous females caught on Chusquea tomentosa in Cerro de la Muerte (Costa Rica). The identity of the species is supported both by the morphological features and by a molecular phylogenetic analysis based on a fragment of the mitochondrial DNA containing the 5’ region of the cytochrome c oxidase 1 (COI) and on the nuclear gene coding for the Elongation factor-1 alpha (EF1α). The taxonomic position of the new species is discussed. An identification key to the Aphidinae species living on plants of Bambusoideae (Poaceae) is presented.
Designación del neotipo de Brachycolus dusmeti Gómez-Menor, 1950, syn. nov. de Brevicoryne brassicae (Linnaeus, 1758) (Hemiptera, Aphididae, Macrosiphini)
Pérez Hidalgo, Nicolás,Nieto Nafría, Juan Manuel
Graellsia , 2004,
Abstract: Not available No disponible
Updated check-list of iberian-balearic Aphidini (Hemiptera, Aphididae)
García Prieto, Francisca,Pérez Hidalgo, Nicolás,Mier Durante, Milagros Pilar,Nieto Nafría, Juan Manuel
Graellsia , 2004,
Abstract: The check-list of species in the Tribe Aphidini (Hemiptera, Aphididae: Aphidinae) recorded to date from the Iberian Peninsula and Balearic Isles is presented, 139 species are listed. A list of the countries (Andorra, Spain and Portugal) and provinces (Spanish) or districts (Portuguese) where each species and subspecies is known is also included. Five species are mentioned for the first time in Iberian-Balearic territory: Aphis callunae Theobald, A. comosa (B rner), A. lantanae Koch (with the subspecies A. lantanae coriaria B rner), A. erigerontis Holman and Schizaphis longicaudata Hille Ris Lambers. Nine species have been removed from the check-list: Aphis euphorbiae Kaltenbach, A. genistae Scopoli, A. pilosellae (B rner), A. salsolae (B rner), A. striata Hille Ris Lambers, Brachyunguis zygophylli (Nevsky), B. suaedus (Paik), Protaphis centaurea (Gómez-Menor) and Schizaphis pilipes (Ossiannilsson). Aphis ruborum B rner & Schilder, 1931 is recognized as the valid name for Aphis ruborum B rner, 1932 syn. nov. and Rhopalosiphum oxyacanthae (Schrank) for Rhopalosiphum insertum (Walker). Two new combinations are established: Xerobion blascoi comb. nov. for Aphis blascoi García Prieto & Sanchís Segovia and Xerobion brutii comb. nov. for Absinthaphis brutii Barbagallo. Five binomens have been re-established: A. althaeae (Nevsky), A. ballotae Passerini, A. longirostris (B rner), A. ononidis (Schouteden) and A. picridis (B rner) to replace A. davletshinae Hille Ris Lambers, A. balloticola Szelegiewicz, A. longirostrata Hille Ris Lambers, A. kaltenbachi Hille Ris Lambers and A. stroyani Szelegiewicz, respectively. The life cycle of Aphis stachydis Mordvilko is given and its males and oviparous females are described. Taxonomic, faunistics and nomenclatural data of other taxa are also given. Se presenta el catálogo de las especies de la tribu Aphidini (Hemiptera, Aphididae: Aphidinae) citadas hasta este momento en la península Ibérica e islas Baleares, con 139 especies. Se relacionan los países (Andorra, Espa a y Portugal) y las provincias (espa olas) o distritos (portugueses) en los que se han citado cada una de las especies y en su caso subespecies. Cinco especies se citan por primera vez en territorios íbero-baleares: Aphis callunae Theobald, A. comosa (B rner), A. lantanae Koch (con la subespecie A. lantanae coriaria B rner), A. erigerontis Holman y Schizaphis longicaudata Hille Ris Lambers. Nueve especies se suprimen del catálogo íbero-balear de la tribu: Aphis euphorbiae Kaltenbach, A. genistae Scopoli, A. pilosellae (B rner), A. salsolae (B rner), A. striata
Detection of the adsorption of water monolayers through the ion oscillation frequency in the magnesium oxide lattice by means of Low Energy Electron Diffraction
M. Guevara-Bertsch,G. Ramírez-Hidalgo,A. Chavarría-Sibaja,E. Avenda?o,J. A. Araya-Pochet,O. A. Herrera-Sancho
Physics , 2015,
Abstract: We investigate the variation of the oscillation frequency of the Mg$^{2+}$ and O$^{2-}$ ions in the magnesium oxide lattice due to the interactions of the surface with water monolayers by means of Low Energy Electron Diffraction. Our key result is a new technique to determine the adsorbate vibrations produced by the water monolayers on the surface lattice as a consequence of their change in the surface Debye temperature and its chemical shift. The latter was systematically investigated for different annealing times and for a constant external thermal perturbation in the range of 110-300 K in order to accomplish adsorption or desorption of water monolayers in the surface lattice.
Un Algoritmo Genético Especializado en Planeamiento de Redes de Distribución Parte I. Fundamentos Técnicos del Algoritmo
Raúl Nicolás Carvajal Pérez
Ingeniería Energética , 2011,
Abstract: The distribution network planning using natural techniques is an actual scientific thematic; specially GeneticAlgorithms. The representative mathematical model in this case has a lot of restrictions. In this paper is presented aspecialized genetic algorithm to realize distribution network expansion studies. The author explains the basicprocedures and experimental work to determine the general parameters magnitude.
Un Algoritmo Genético Especializado en planeamiento de redes de distribución Parte II. Detalles del algoritmo y su aplicación
Raúl Nicolás Carvajal Pérez
Ingeniería Energética , 2011,
Abstract: The first section explained the specifics characteristics of network planning and the selected method for genetic operators.In this papers, expose details about the algorithm steps, the mathematical procedures and some applications.
Steady-state kinetics of Roystonea regia palm tree peroxidase  [PDF]
Laura Sánchez Zamorano, Nazaret Hidalgo Cuadrado, Patricia Pérez Galende, Manuel G. Roig, Valery L. Shnyrov
Journal of Biophysical Chemistry (JBPC) , 2012, DOI: 10.4236/jbpc.2012.31002
Abstract: Royal palm tree peroxidase (RPTP) has been isolated to homogeneity from leaves of Roystonea regia palm trees. The enzyme purification steps included homogenization, (NH4)SO4 precipitation, extraction of palm leaf colored compounds and consecutive chromatography on Phenyl-Sepharose, TSK-Gel DEAE-5PW and Superdex-200. The novel peroxidase was characterized as having a molecular weight of 48.2 ± 3.0 kDa and an isoelectric point pI 5.4 ± 0.1. The enzyme forms dimers in solution with approximate molecular weight of 92 ± 2 kDa. Here we investigated the steady-state kinetic mechanism of the H2O2-supported oxidation of different organic substrates by RPTP. The results of the analysis of the initial rates vs. H2O2 and reducing substrate concentrations were seen to be consistent with a substrate-inhibited Ping-Pong Bi-Bi reaction mechanism. The phenomenological approach used expresses the peroxidase Ping-Pong mechanism in the form of the Michaelis-Menten equation and affords an interpretation of the effects in terms of the kinetic parameters KmH2O2, KmAH2, kcat, KSIH2O2, KSIAH2 and of the microscopic rate constants k1 and k3 of the shared three-step peroxidase catalytic cycle. Furthermore, the concentration and time-dependences and the mechanism of the suicide inactivation of RPTP by hydrogen peroxide were studied kinetically with guaiacol as co-substrate. The turnover number (r) of H2O2 required to complete the inactivation of the enzyme was 2154 ± 100 and the apparent rate constants of catalysis 185 s–1 and 18 s–1.
Larva Migrans Visceral Visceral Larva Migrans
Diego Aldunate G,Carlos Pérez B,Carlos Hidalgo S
Revista chilena de pediatría , 1983,
Abstract:
Homeostasis del hierro.: Mecanismos de absorción, captación celular y regulación Iron homeostasis: Mechanisms of absorption, uptake, and regulation
Gladys Pérez,Daniela Vittori,Nicolás Pregi,Graciela Garbossa
Acta bioqu?-mica cl?-nica latinoamericana , 2005,
Abstract: El hierro es un elemento esencial para los organismos vivientes. En soluciones acuosas puede encontrarse en dos estados de oxidación estables: ferroso (Fe2+) y férrico (Fe3+), propiedad que le permite participar en reacciones que abarcan gran parte de la bioquímica. En el organismo, el hierro se encuentra formando parte de dos compartimientos: uno funcional y otro de depósito. El transporte de hierro unido a transferrina permite el intercambio del metal entre ambos compartimientos mientras que su exceso se deposita intracelularmente como ferritina o hemosiderina. En condiciones fisiológicas, el hierro se encuentra asociado a una proteína ya que su presencia en forma aislada puede producir da os graves en los tejidos. Esta toxicidad se debe a la habilidad del hierro libre de generar especies reactivas de oxígeno. Dado que tanto la deficiencia como la sobrecarga de este metal esencial son perjudiciales, su absorción, concentración y estado redox deben ser regulados cuidadosamente. En este trabajo se revisan las vías que median la absorción intestinal y la incorporación celular de hierro y se detallan los diferentes mecanismos que participan en su homeostasis. Finalmente, y considerando que el espectro de los desórdenes conocidos del metabolismo del hierro se ha expandido en los últimos a os, se describen algunas de las alteraciones más comunes. Iron is an essential nutrient required by every living being. This transition metal is involved in the majority of the metabolic processes, partly because of its ability to reversibly and readily cycle between ferrous (Fe2+) and ferric (Fe3+) oxidation states. Iron must be transported and stored as a component of protein complexes. Ferric ions circulate bound to plasma protein transferrin and accumulate within cells in the form of ferritin or hemosiderin. This is due to the fact that iron as a free cation can participate in a number of reactions to produce free radical species, which in turn can severely damage organs. Taking into account that both iron deficiency and iron overload are deleterious, a strict balance between iron absorption and utilization is required. In this work, the distinct pathways of gastrointestinal absorption and cellular uptake of iron are reviewed, giving details of the mechanisms involved in iron homeostasis under different conditions. Condition of iron deficiency and overload are discussed in terms of mechanisms leading to restoration of iron homeostasis.
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