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Search Results: 1 - 10 of 145408 matches for " Erica F. Tocho "
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Genetic analysis of greenbug populations of Schizaphis graminum (Hemiptera: Aphididae) from Argentina and Chile based on enzyme variability
Saldúa,Luciana; Tacaliti,María S.; Tocho,Erica; Dixon,Anthony F. G.; Castro,Ana M.;
Revista de la Sociedad Entomol?3gica Argentina , 2011,
Abstract: twenty-nine schizaphis graminum (rondani) populations and sixty clones collected from very contrasting regions of argentina and chile were investigated electrophoretically. a high degree of enzymatic polymorphism was found. the enzymatic structure was described for the esterase system, finding nine different loci. latitudinal stratification was determined and populations were associated into three groups, according to the latitude they were collected from. the 90% of loci resulted polymorphic in the first group and 100% of loci were polymorphic in the rest. observed heterozygosity was lower than expected. no group had fixed alleles according to fsr values; group one had a slight heterozygous excess, while the other groups showed slight positive fsr values, because there was a homozygous excess. according to frt, the third group showed the highest value that was in concordance with the highest gene flow value. three populations could not be included in any group. the α-carboxyl-esterase was always present, also in clones and populations which were located in non agricultural zones, implicating that the insecticide resistance is well spread throughout the argentinean and chilean territory. no relationship was found between the enzymatic patterns and the biotype or with the host species where the aphids were collected from.
Genetic analysis of greenbug populations of Schizaphis graminum (Hemiptera: Aphididae) from Argentina and Chile based on enzyme variability Análisis genético de las poblaciones del pulgón verde Schizaphis graminum (Hemiptera: Aphididae), colectadas en Argentina y Chile, basado en su variabilidad enzimática
Luciana Saldúa,María S. Tacaliti,Erica Tocho,Anthony F. G. Dixon
Revista de la Sociedad Entomol?3gica Argentina , 2011,
Abstract: Twenty-nine Schizaphis graminum (Rondani) populations and sixty clones collected from very contrasting regions of Argentina and Chile were investigated electrophoretically. A high degree of enzymatic polymorphism was found. The enzymatic structure was described for the esterase system, finding nine different loci. Latitudinal stratification was determined and populations were associated into three groups, according to the latitude they were collected from. The 90% of loci resulted polymorphic in the first group and 100% of loci were polymorphic in the rest. Observed heterozygosity was lower than expected. No group had fixed alleles according to Fsr values; group one had a slight heterozygous excess, while the other groups showed slight positive Fsr values, because there was a homozygous excess. According to Frt, the third group showed the highest value that was in concordance with the highest gene flow value. Three populations could not be included in any group. The α-carboxyl-esterase was always present, also in clones and populations which were located in non agricultural zones, implicating that the insecticide resistance is well spread throughout the Argentinean and Chilean territory. No relationship was found between the enzymatic patterns and the biotype or with the host species where the aphids were collected from. Veintitrés poblaciones de Schizaphis graminum (Rondani) y sesenta clones colectados en regiones muy contrastantes de la Argentina y Chile fueron investigadas electroforéticamente. Se encontró un alto grado de polimorfismo enzimático. La estructura enzimática fue descripta para el sistema estearasa y se encontraron nueve loci diferentes. Se determinó que existe estratificación latitudinal, las poblaciones fueron asociadas en tres grupos de acuerdo a la latitud donde fueron colectadas. El 90% de los loci resultaron polimórficos en el primer grupo y el 100% de los loci lo fueron en el resto. La heterocigosidad observada fue menor que la esperada. Ningún alelo fue fijado, de acuerdo con el valor del Fsr. El primer grupo tuvo un ligero exceso de heterocigosis, mientras que los demás grupos mostraron valores ligeramente positivos de Fsr, debido al exceso de homocigosis. Con respecto a Frt, el tercer grupo mostró un valor alto que estuvo en concordancia con el alto valor de flujo génico. Tres poblaciones no pudieron ser incluidas en ningún grupo. Las α-carboxil- estearasas siempre estuvieron presentes incluso en clones y poblaciones colectadas en zonas no agrícolas, lo que implica que la resistencia a insecticidas está ampliamente extendida a
Evaluación de la resistencia a Schizaphis graminum (Hemiptera: Aphididae) en cebada Assessment of resistance against Schizaphis graminum (Hemiptera: Aphididae) in barley
Erica F. Tocho,Ana M. Marino de Remes Lenicov,Ana M. Castro
Revista de la Sociedad Entomol?3gica Argentina , 2012,
Abstract: El pulgón verde de los cereales, Schizaphis graminum (Rondani), es una de las principales plagas de estos cultivos en el mundo y también presente en Argentina. Si bien el control químico es la práctica más utilizada, el uso de variedades resistentes (uno de los componentes principales del MIP) es la estrategia más efectiva y ambientalmente más amigable para el control de plagas. Dado que las plantas presentan distintos mecanismos que les permiten defenderse de los insectos, el objetivo de este trabajo fue caracterizar la resistencia a Schizaphis graminum en una población de líneas recombinantes de cebada, e identificar aquellas con mejores características, portadoras de genes de resistencia a este insecto. La antixenosis fue analizada por la prueba de libre selección de hospederos. La antibiosis se evaluó por los parámetros del ciclo y el desarrollo del áfido y la tolerancia por características de crecimiento de las plantas bajo infestación. Al menos ocho líneas antibióticas fueron más tolerantes que sus testigos, presentando similares pesos secos, área foliar y contenido de clorofila bajo infestación. Estas líneas portadoras de genes de resistencia pueden ser de utilidad en los planes de mejora de la cebada. Greenbug, Schizaphis graminum (Rondani) is one of the major pests of cereals around the world that is present in Argentina. Chemical control is the most widely used practice; however, the use of resistant varieties, one of the main components in IPM, is the most effective and environmentally sustainable strategy of control. Since plants have different types of insect resistance that allow them to defend against pests, the aim of the current study was to characterize the resistance to Schizaphis graminum in a population of recombinant inbred lines of barley and to identify lines with improved characteristics that enable the development of commercial cultivars. Antixenosis was studied by the host free choice test. Antibiosis was assessed by means of aphid life cycle and developmental traits. Tolerance mechanism was analyzed by plant growth parameters. At least eight lines carrying antibiosis were more tolerant than their controls, with similar dry weight, leaf area and chlorophyll contents, under infestation. These lines could provide resistance genes against this aphid pest and would be useful in plant breeding programs.
Improving stroke outcome: the benefits of increasing availability of technology
Heller,Richard F.; Langhorne,Peter; James,Erica;
Bulletin of the World Health Organization , 2000, DOI: 10.1590/S0042-96862000001100009
Abstract: introduction: a decision analysis was performed to explore the potential benefits of interventions to improve the outcome of patients admitted to hospital with a stroke, in the context of the technology available in different parts of the world. methods: the outcome of death or dependency was used with a six-month end-point. results: four settings were identified that would depend on the resources available. the proportion of stroke patients who were dead or dependent at six months was 61.5% with no intervention at all. setting 4, with the only intervention being the delayed introduction of aspirin, produced a 0.5% absolute improvement in outcome (death or dependency), and the addition of an organized stroke unit (setting 3) produced the largest incremental improvement, of 2.7%. extra interventions associated with non-urgent computed tomography and thus the ability to avoid anticoagulation or aspirin for those with a haemorrhagic stroke (setting 2), and immediate computed tomography scanning to allow the use of thrombolytics in non-haemorrhagic stroke (setting 1), produced only small incremental benefits of 0.4% in each case. discussion: to reduce the burden of illness due to stroke, efforts at primary prevention are essential and likely to have a greater impact than even the best interventions after the event. in the absence of good primary prevention, whatever is possible must be done to reduce the sequelae of stroke. this analysis provides a rational basis for beginning the development of clinical guidelines applicable to the economic setting of the patient.
Forma??o de agentes comunitários em ambiente e saúde na Col?nia Juliano Moreira: uma abordagem etnográfica
Cecchetto, Fátima;Monteiro, Simone;Fernandes, Erica;
Trabalho, Educa??o e Saúde , 2010, DOI: 10.1590/S1981-77462010000200006
Abstract: the article analyzes the process of training community health agents in a community in the western zone of rio de janeiro, carried out under a project designed to build participatory approaches in health. based on the ethnographic observation of community and educational practices and by using questionnaires, the study aimed to contextualize the development of the course and analyze the participants' view about the expectations and learning of knowledge on health and the environment. the data show that the course met part of the students' expectations and resulted in the strengthening of local community networks and in some of the participants' social capital. the article aims to contribute to an anthropology of the educational activities, undertaken in formal and informal spaces, both within the context of the formulation and development of such actions and in the vision of the different players involved in the educational programs.
Dermatology Resident Generated Textbook Questions as a Resident-Centered Educational Strategy  [PDF]
Nathan A. Davis, Kimberly Cooper, Erica B. Kelly, Sharon S. Raimer, Richard F. Wagner
Journal of Cosmetics, Dermatological Sciences and Applications (JCDSA) , 2013, DOI: 10.4236/jcdsa.2013.33A2004
Abstract:

Background: Textbook conferences are widely used by dermatology residency programs in the United States to provide educational exposure to the specialty. Typically an entire textbook is reviewed each academic year. However, residents may be uncertain about mastery of the assigned readings. Since most dermatology textbooks do not provide questions about the material presented at the end of each chapter, an innovative senior resident from our program wrote questions about each chapter and offered them to the other residents prior to scheduled discussions of the assigned materials. Methods: A pilot study for resident generated quizzes about assigned textbook reading in general dermatology was developed, implemented, and assessed by anonymous completion of a Likert Scale by participants. Results: Participants indicated that quizzes better prepared them for the annual dermatology in-service examination and they thought that the additional creation of quiz materials in the subspecialty areas of dermatopathology and dermatologic surgery would be useful. Conclusion: Resident generated quizzes are a novel approach to the learning environment during dermatology residency for residency programs and may be useful for other residency programs that utilize textbook conferences. Additional research is needed.

Streptococcal Protein G Enhances Antibody Binding to Platinum Sensor Surfaces  [PDF]
Michael E. Stephens, Terri N. Ellis, Jay S. Huebner, Doria F. Bowers, Erica M. Kelly
Journal of Sensor Technology (JST) , 2015, DOI: 10.4236/jst.2015.51001
Abstract: Photo-Electric Microbe Sensor is a patented biotechnology that detects microbes in aqueous solution by measuring the change in photo-voltage in response to UV light stimulation of a platinum (Pt) disk surface on an electrode before and after immunoprecipitation of microbes. This study aimed to increase the sensitivity of microbe detection by pre-adsorbing recombinant Streptococcal Protein G (PG), to the Pt sensor surface. Streptococcal PG binds the Fc region of mammalian IgG molecules and we investigated the association of PG to Pt and the resulting ability to tether antibodies to the Pt-PG surface. An ELISA protocol was optimized to detect the presence of mouse monoclonal antibodies tethered to Pt immunoaffinity disks, and to determine the recommended blocking solution and reagent concentrations. Our results demonstrate that PG binds to bare Pt, increases IgG affinity to the Pt surface following Superblock Buffer application, and together offers design-options for Pt-based sensor technologies.
Atlas and Catalog of Collisional Ring Galaxies
Barry F. Madore,Erica Nelson,Kristen Petrillo
Physics , 2009, DOI: 10.1088/0067-0049/181/2/572
Abstract: We present a catalog and imaging atlas of classical (collisional) RING galaxies distilled from the Arp-Madore Atlas of Southern Peculiar Galaxies and Associations and supplemented with other known RING galaxies from the published literature. The catalog lists the original host object, compiles available redshifts and presents newly determined positions for the central (target) galaxy and its nearest companion(s). 127 collisional RING systems are illustrated and their components identified. All of the RINGS have plausible colliders identified; many are radial-velocity confirmed companions. Finally, we make note of the existence of a rare sub-class of RING galaxies exemplified by AM 2136-492, double/concentric RING galaxies. These objects are predicted by numerical simulations, but they appear to be quite rare and/or short-lived in nature.
Análisis de nuevos estándares para reducir datos de gravedad: aplicación en Tierra del Fuego
Pedraza De Marchi,Ana Carolina; Tocho,Claudia;
Geoacta , 2011,
Abstract: the main objective of this study was to investigate the use of new standards and procedures for reducing gravity data in order to improve the precision, accuracy, and usefulness of geophysical gravity anomalies. the new standards take into account the increased current computing power, the modern satellite technology to determine the height and positioning of the gravity stations, the improved topographic / bathymetric databases, and new mathematical algorithms. they are based on internationally accepted procedures, protocols, equations and parameters, and in many cases differ from those presented in current geophysical textbooks and existing gravity databases. the most important change that the new standards suggest, due to the greater use of global positioning system (gps) for field gravimetric work, is the use of terrestrial reference ellipsoid adopted internationally to define the vertical datum. the anomalies calculated with the new standards could be modified by the adjective "ellipsoidal" to differentiate them from the anomalies calculated by conventional elevations referred to the geoid. gravity reductions, following the traditional and new recommendations and standards were calculated in the province of tierra del fuego. we used digital elevation models and geopotential models to assess the effectiveness of its use in gravity reductions. the land gravimetric data were integrated with free air anomalies derived from satellite altimetry in the sea, in order to compute an ellipsoidal isostatic anomaly map.
Análisis de nuevos estándares para reducir datos de gravedad: aplicación en Tierra del Fuego
Ana Carolina Pedraza De Marchi,Claudia Tocho
Geoacta , 2011,
Abstract: El objetivo principal de este trabajo consistió en investigar el uso de nuevos estándares y procedimientos para reducir datos de gravedad con el fin de mejorar la precisión, exactitud y utilidad geofísica de las anomalías de gravedad. Los nuevos estándares tienen en cuenta el mayor poder computacional actual, la moderna tecnología de posicionamiento satelital para determinar la altura y el posicionamiento de las estaciones gravimétricas, las mejoras en las bases de datos topográficos/batimétricos y nuevos algoritmos matemáticos. Están basados en procedimientos, protocolos, ecuaciones y parámetros internacionalmente aceptados y que en muchos casos difieren de los presentados en los actuales libros de textos y bases de datos gravimétricos existentes. El cambio más importante que sugieren los nuevos estándares es el uso del elipsoide de referencia terrestre internacionalmente adoptado para definir el datum vertical o superficie de referencia para las alturas (Hinze et al., 2005), debido al creciente uso del Sistema Global de Posicionamiento (GPS) para realizar trabajos de campo gravimétricos. Las anomalías calculadas con los nuevos estándares podrían ser modificadas por el adjetivo "elipsoidal" (Hinze et al., 2005) para diferenciarlas de las anomalías que se calculan mediante las elevaciones convencionales referidas al geoide. Se usó la información existente en la provincia de Tierra del Fuego para hacer reducciones, siguiendo los procedimientos tradicionales y las nuevas recomendaciones y estándares. Se utilizaron los modelos digitales de terreno y modelos geopotenciales a fin de evaluar la eficacia de su uso en las reducciones gravimétricas. Se integró la información gravimétrica terrestre con anomalías de aire libre derivadas de la altimetría satelital en el mar, en un mapa combinado de anomalías isostáticas elipsoidales. The main objective of this study was to investigate the use of new standards and procedures for reducing gravity data in order to improve the precision, accuracy, and usefulness of geophysical gravity anomalies. The new standards take into account the increased current computing power, the modern satellite technology to determine the height and positioning of the gravity stations, the improved topographic / bathymetric databases, and new mathematical algorithms. They are based on internationally accepted procedures, protocols, equations and parameters, and in many cases differ from those presented in current geophysical textbooks and existing gravity databases. The most important change that the new standards suggest, due to the greate
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