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Susceptibilidad de Tetranychus urticae Koch (Acari: Tetranychidae) Colectada en Primula obconica Hance y Convolvulus arvensis L. a Acaricidas
Flores F,Alberto; Silva A,Gonzalo; Tapia V,Maritza; Casals B,Pedro;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000200014
Abstract: the use of acaricides of high toxicity in the production and handling of ornamental plants should be a matter of consumer concern. the susceptibility of two populations of tetranychus urticae was assessed: one collected from primula obconica hance and the other from convolvulus arvenis l as susceptible reference strain to the acaricides dicofol, abamectin alone and mixed with the surfactant phosphatidylcholine, azadirachtin, sulfur, pyridaben and fenazaquin. the evaluated parameters were mortality, lethal concentration 50% (lc50) and 90% (lc90), lethal time 50% (lt50) and 90% (lt90), effectiveness and index of resistance (ir). the experimental design was completely at random. each treatment had ?, ?, 1, 2 and 4x of the doses indicated by the manufacturer, five replicates and were sprayed with a potter spray tower. the results showed that the lc50 for azadirachtin and sulfur was significantly high. regarding the population from p. obconica, abamectin alone and in mixture with phosphatidylcholine and fenazaquin showed the highest efficiency. azadirachtin and sulfur were the acaricides showing the slowest activity and the resistance index indicated that the population collected in p. obconica should be considered susceptible to all the evaluated acaricides
Susceptibilidad de Tetranychus urticae Koch (Acari: Tetranychidae) Colectada en Primula obconica Hance y Convolvulus arvensis L. a Acaricidas Susceptibility of Tetranychus urticae Koch (Acari: Tetranychidae) collected in Primula obconica Hance and Convolvulus arvensis L. to acaricides
Alberto Flores F,Gonzalo Silva A,Maritza Tapia V,Pedro Casals B
Agricultura Técnica , 2007,
Abstract: El uso de acaricidas de alta toxicidad en la producción y manejo de plantas ornamentales es un tema que debería preocupar a los consumidores. Se evaluó la susceptibilidad en laboratorio de dos poblaciones de Tetranychus urticae colectadas una en Primula obconica Hance y la otra en Convolvulus arvenis L, que se usó como raza sensible de referencia, a dicofol, abamectina, sola y en mezcla con el surfactante fosfatidilcolina, azadirachtina, azufre, pyridaben y fenazaquin. Las variables evaluadas fueron mortalidad, concentración letal 50% (CL50) y 90% (CL90), tiempo letal 50% (TL50) y 90% (TL90), eficacia e índice de resistencia (IR). El dise o experimental fue completamente al azar. Cada acaricida se evaluó en , , 1, 2 y 4 veces la dosis recomendada según el fabricante, y cada tratamiento tuvo cinco repeticiones y se aplicaron con una torre de Potter. Los resultados muestran que para azadirachtina y azufre la CL50 fue mayor. En la población proveniente de P. obconica, abamectina sola y en mezcla con fosfatidilcolina y fenazaquin propiciaron la mayor eficiencia. Azadirachtina y azufre demostraron ser los acaricidas de más lenta acción y el índice de resistencia indica que la población colectada en P. obconica debe ser considerada como sensible a todos los acaricidas evaluados. The use of acaricides of high toxicity in the production and handling of ornamental plants should be a matter of consumer concern. The susceptibility of two populations of Tetranychus urticae was assessed: one collected from Primula obconica Hance and the other from Convolvulus arvenis L as susceptible reference strain to the acaricides dicofol, abamectin alone and mixed with the surfactant phosphatidylcholine, azadirachtin, sulfur, pyridaben and fenazaquin. The evaluated parameters were mortality, lethal concentration 50% (LC50) and 90% (LC90), lethal time 50% (LT50) and 90% (LT90), effectiveness and index of resistance (IR). The experimental design was completely at random. Each treatment had , , 1, 2 and 4X of the doses indicated by the manufacturer, five replicates and were sprayed with a Potter spray tower. The results showed that the LC50 for azadirachtin and sulfur was significantly high. Regarding the population from P. obconica, abamectin alone and in mixture with phosphatidylcholine and fenazaquin showed the highest efficiency. Azadirachtin and sulfur were the acaricides showing the slowest activity and the resistance index indicated that the population collected in P. obconica should be considered susceptible to all the evaluated acaricides
Estudio de puertas catalíticas en sensores de gas en tecnología de SiC
Casals, O.,Haffar, M.,Barcones, B.,Romano, A.
Boletín de la Sociedad Espa?ola de Cerámica y Vidrio , 2004,
Abstract: In this work the chemical and structural characterisation of metallic layers of Pt and TaSix, employed as catalytic gates in high temperature gas sensors based on MOS devices on SiC substrates, is presented. For the study layers of different thickness have been deposited on Si substrates. The results show that the roughness of the layers increases with the reduction of the thickness of Pt and with annealing, which should give rise to an increase in the sensitivity and response speed of the devices. Another consequence of the annealing is the chemical transformation of the gate’s materials that, for thin films of Pt with TaSix, produces the complete transformation of Pt into Pt2Ta, which might affect the catalytic properties of the gate. The first electrical results show that, even with thick and compact Pt layers, the SiC-based MOS tunnel diodes are sensitive to CO and NO2 gases, although the response time is relatively long. its response speed is too slow. En este trabajo se presenta un estudio químico y estructural de las capas metálicas de Pt y TaSix utilizadas como puerta catalítica en sensores de gas de alta temperatura basados en dispositivos MOS de SiC. Para ello se han depositado capas de diferentes espesores sobre substratos de Si. Los resultados muestran que con la reducción del espesor de Pt y con un recocido se consigue aumentar la rugosidad de las capas de puerta, lo que debería aumentar la sensibilidad y la velocidad de respuesta de los dispositivos que las incorporasen. Otro efecto del recocido es la transformación química del material de la puerta que, para capas delgadas de Pt con TaSix, produce la transformación total Pt en Pt2Ta, lo que podría afectar a las características catalíticas de la puerta. Los primeros resultados eléctricos indican que, a pesar de que las capas de Pt empleadas son gruesas y compactas, los diodos MOS túnel de SiC son sensibles a los gases CO y NO2, aunque presentan una velocidad de respuesta bastante lenta.
‘Corrandescola’: del cant a la improvisació poètica / ‘Corrandescola’: Du chant à l’improvisation poétique Corrandescola’: From song to poetic improvisation ‘Corrandescola’: del canto a la improvisación poética
Albert Casals
Temps d'Educació , 2012,
Abstract: Glosa o can ó improvisada és el nom d’una activitat comunicativa que es dóna en el si d’una comunitat i que es vehicula a través de versos improvisats que es canten sobre melodies d’arrel tradicional. En la primera part de l’article s’aborda la configuració textual, musical i escènica d’aquest gènere poèticomusical per presentar a continuació el projecte Corrandescola. Es mostra com aquest projecte ha desenvolupat una proposta didàctica que s’ha dut a terme en diverses escoles de Catalunya i que es fonamenta en les possibilitats educatives de la can ó improvisada. A l’última part de l’article es plantegen les oportunitats i limitacions de la proposta en relació al descobriment poètic per part de l’alumnat de cicle superior de Primària. Una de les conclusions que se n’extreu és que la can ó improvisada pot esdevenir una forma efica d’acostament a la poesia gràcies al fet que es basa en un paradigma comunicatiu altament significatiu i motivador des de la perspectiva de l’alumnat participant. ____________________________________________________ La glosa ou chanson improvisée est une activité communicative qui se produit au sein d'une communauté et qui consiste à l’interprétation chantée de vers improvisés dont les mélodies sont de racine traditionnelle. La première partie de cet article présente la configuration textuelle, musicale et théatrale de ce genre poétique-musical puis continue avec la présentation du projet Corrandescola. Nous montrons comment autour de ce projet s’est développé une proposition didactique qui a été mise en place dans plusieurs écoles de la Catalogne. Cette approche est basée sur le potentiel éducatif de la chanson improvisée. Dans la dernière partie de l'article nous discutons les possibilités et les limites de l’approche didactique par rapport à la découverte de la poésie par les élèves de l'école primaire. Une des conclusions que nous en tirons est que la chanson improvisée peut devenir un moyen efficace d'aborder la poésie grace au fait qu’elle s’appuie sur un paradigme communicatif de haute signification et très motivant pour les élèves qui y participent. Glosa or improvised song is the name given to a communicative activity that takes place within a community and is channelled through improvised verses sung to tunes with traditional roots. The first part of the paper deals with the arrangement of the lyrics, music and performance of this musical poetic form in order to subsequently present the Corrandescola project. It shows how this project has developed a didactic proposal that has been put into practice in several schools
Entre el ocaso y la ilusión. Hannah Arendt y las posibilidades creadores de la acción humana / Between Decline and Hope. Hannah Arendt and the Creating Possibilities of Human Action
Marcelo Casals
Revista SudHistoria , 2010,
Abstract: The lack of hope in the XX Century, the extremes of exterminating totalitarianism and the inhumanity of mass societies have put in check the concept of human being and his collective creative abilities. Hannah Arendt, intellectual, of Jew-German origins, characterized her own intellectual work for a deep analysis concerning these aspects. In the following article it is pretend to analyze her proposal in base to the “action” concept, understanding this as the human ability to create innovation and impressibility in a collective manner, and insert it in an equality and liberty environment.
Electromagnetic Quantum Field Theory on Kerr-Newman Black Holes
Marc Casals
Physics , 2008,
Abstract: We study classical and quantum aspects of electromagnetic perturbations on black hole space-times. We develop an elegant formalism introduced by Wald, which sets up the theory of linear perturbations in a Type-D background in a compact and transparent manner. We derive expressions for the electromagnetic potential in terms of the single Newman-Penrose scalar \phi_0.This enables the formulation of the quantum theory of the electromagnetic field as that of a complex scalar field. We study the separable field equations obeyed by the various Newman-Penrose scalars in the Kerr-Newman background and find, for various limits, the asymptotic behaviour of the radial and angular solutions. We correct and build on a study by Breuer, Ryan and Waller to find a uniformly valid asymptotic behaviour for large frequency of the angular solutions and the eigenvalues. We follow Candelas, Chrzanowski and Howard (CCH) in their canonical quantization of the electromagnetic potential and field. We perform an asymptotic analysis of the form of the renormalized stress-energy tensor (RSET) in the past Boulware state close to the horizon. Unlike results in CCH, its leading order behaviour close to the horizon corresponds to minus the stress tensor of a thermal distribution at the Hawking temperature rigidly rotating with the horizon. We prove that expressions in CCH for the expectation value of the stress tensor in the past Boulware, past Unruh and |CCH> states lead to a lack of symmetry of the RSET under parity, even though this is a symmetry of the physical system. We derive the correct symmetric expressions and present a detailed analysis of the resulting RSETs.
Overtwisted Disks and Exotic Symplectic Structures
Roger Casals
Mathematics , 2014,
Abstract: The symplectization of an overtwisted contact structure in Euclidean 3--space is shown to be an exotic symplectic structure on Euclidean 4--space. The technique can be extended to produce exotic symplectic structures in higher dimensional Euclidean spaces using a GPS--structure and applies to symplectizations of appropriate open contact manifolds.
Quilotorax en Ni os Chylothorax in Children
Maritza Pedemonte B,Iván Cabrera A
Revista chilena de pediatría , 1984,
Abstract:
Hiperostosis esquelética idiopática difusa (DISH), respecto de dos casos Diffuse idiopathic skeletal hiperostosis, respect of two cases
Rodrigo Urzúa B,Maritza Rahal E
Revista de Otorrinolaringología y Cirugía de Cabeza y Cuello , 2012,
Abstract: La hiperostosis esquelética idiopática difusa (DISH) o enfermedad de Forestier es una patología que presenta como principal manifestación la osificación del ligamento longitudinal anterior (LLA) y la formación de puentes óseos intervertebrales. Las repercusiones otorrinolaringológicas con poca frecuencia son descritas, siendo la disfagia, la disfonía y la disnea los síntomas más comunes. Presentamos dos casos clínicos de DISH en pacientes de sexo masculino de setenta y cuatro a os y otro de setenta y un a os respectivamente, con disfagia de varias semanas de evolución asociado a disfonía y disnea en un caso. Realizamos la discusión de ambos casos y de las manifestaciones otorrinolaringológicas de esta patología. Diffuse idiopathic skeletal hiperostosis (DISH) or Forester's disease is a pathology characterized by the ossification of the anterior longitudinal ligament (ALL) and the formation of intervertebral osseous bridges. The otolaryngology repercussions are rarely described, dysphagia, hoarseness and dyspnea being the most common symptoms. We present a clinical case of two patients with DISH in a 74 year-old male patient and another of 71 year-old respectively, suffering from several weeks of dysphagia associated with dysphonia and dyspnea in one case. We are going to discuss both cases together with the otolaryngological manifestations of this pathology.
Bump time-frequency toolbox: a toolbox for time-frequency oscillatory bursts extraction in electrophysiological signals
Fran?ois B Vialatte, Jordi Solé-Casals, Justin Dauwels, Monique Maurice, Andrzej Cichocki
BMC Neuroscience , 2009, DOI: 10.1186/1471-2202-10-46
Abstract: in this work we propose a user-friendly stand-alone toolbox, which models in a reasonable time a bump time-frequency model from the wavelet representations of a set of signals. The software is provided with a Matlab toolbox which can compute wavelet representations before calling automatically the stand-alone application.The tool is publicly available as a freeware at the address: http://www.bsp.brain.riken.jp/bumptoolbox/toolbox_home.html webciteThe structural organization (which elements are relevant) and associated functional role (how these elements play a role in brain dynamics) of electroencephalographic (EEG) oscillations are still far from being completely understood. Oscillatory activity can be separated in background (or ongoing) and transient burst pattern activities. The background EEG is constituted by regular waves, whereas bursts are transient and with higher amplitudes: cortical dynamics do not follow continuous patterns, but instead operates in steps, or frames [1]. These bursts are organized local activities, most likely to be representative of local synchronies. Synchrony among oscillating neural assemblies is a plausible candidate to mediate functional connectivity, and therefore to allow the formation of spatiotemporal representations [2,3]. Oscillatory bursts should consequently play a specific functional role, distinct from ongoing background EEG activity (which does not mean however that background activity cannot convey information). They are correlated with reciprocal dynamic connections of neural structures, which can be considered as distributed local networks of neurons [4]. Together, distant neural assemblies are involved in collective dynamics of synchronous neuronal oscillations [3], taking the shape of oscillatory patterns.EEG activities are usually analyzed using either time or frequency representations of event related potentials (ERP), which can be interpreted as the reorganization of the spontaneous brain oscillations in response
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