Preservice Teacher Sense-Making as They Learn to Teach Reading as Seen Through Computer-Mediated Discourse

Abstract This collective case study used methods of discourse analysis to consider what computer-mediated collaboration might reveal about preservice teachers’ sense-making in a field-based practicum as they learn to teach reading to children identified as struggling readers. Researchers agree that field-based experiences coupled with time for reflection benefit preservice teachers as they learn to teach reading. However, research is not as clear about which features of practicum experiences lead to preservice teacher learning, which may contribute to preservice teacher misconceptions, and how learning about reading instruction might be rendered more visible to researchers. Grounded in sociocultural perspectives, analysis focused on language as a mediating tool for the construction of knowledge. Data collection spanned three semesters in a literacy assessment and intervention practicum. Preservice teachers constructed understandings of readers and reading instruction through reflecting, planning, and articulating their decision-making processes with one another in the online discussion board. Findings indicated that analysis of preservice teachers’ computer-mediated discussions provided a window into their sense-making processes. While some preservice teachers’ discourse demonstrated marked growth, other preservice teachers’ limited use of precise language related to reading assessment and intervention frequently inhibited their developing understandings and instructional decisions. As well, some of the decisions instructors made likely contributed to several PST misconceptions. We conclude with implications for computer-supported collaborative environments in teacher education as a means to make preservice teacher learning more visible and accessible as a tool for teaching and learning

Tomato spotted wilt and peanut bud necrosis viruses

The peanut bud necrosis virus (PBNV) nd tomato spotted wilt virus (TSWV), both tospoviruses, cause economically important diseases in peanut..

Operacionalização do conceito de resiliência de forrageiras sob pastoreio rotativo aos distúrbios de mudanças climáticas

A resiliência de forrageiras sob pastoreio rotativo aos distúrbios de mudanças climáticas, em particular aos efeitos do déficit hídrico em veranicos, é um atributo básico para alcançar a sustentabilidade do sistema de produção de leite. Este trabalho apresenta um método baseado na dinâmica de sistemas para estimar os índices de resiliência: dureza, robustez, rapidez de recuperação e elasticidade. Um metamodelo para o manejo do ecossistema planta-animal foi adaptado para simular os efeitos dos distúrbios causados por veranicos no estoque de matéria seca dos piquetes. Os resultados dos experimentos in silico mostram diferenças entre as resiliências de dois cultivares de forrageiras para uma mesma magnitude de distúrbio e diferenças devido a época de ocorrência do déficit hídrico ser na fase de crescimento da forrageira ou na fase de uso dos piquetes pelos animais. O índice de rapidez de recuperação mostrou aderência conceitual para as condições de pastoreio rotativo, devido à premência de tempo na definição da entrada e saída dos animais nos piquetes. Concluiu-se que a operacionalização e avaliação da resiliência geram informações sobre a dinâmica do estoque de matéria seca ofertada para os animais e que estas informações são úteis para o planejamento do pastoreio rotativo

Algoritmo de visión estereo en tiempo real implementado en GPGPU

En el este trabajo se presenta una implementación en tiempo real de un sistema de visión artificial en tres dimensiones sobre GPGPU. Se logra optimizar el procesamiento de visión estéreo mediante el algoritmo de Suma de Diferencias Absolutas (SAD), seleccionado en virtud de su costo computacional moderado. Se aplican sobre la imagen resultante sendos kernels de sustracción de fondo y suavizado, con el objeto de minimizar los errores de procesamiento intrínsecos de SAD, obteniéndose en forma experimental los parámetros óptimos para cada kernel. Se aplica esta cadena de procesamiento sobre una plataforma basada en GPGPU, y sobre un equipo basado en CPU convencional de arquitectura x86. Se comparan los resultados con el mismo procesamiento ejecutado en una CPU convencional y se demuestra una mejora 13x en el tiempo de ejecución, y por consecuencia, la factibilidad de aplicar el método para procesamiento de video en tiempo real utilizando GPGPUs como plataforma de ejecución, hecho que permite proyectar futuros trabajos en aplicaciones industriales de tiempo real que se valgan de la visión 3D para verificación de ensamble de productos sobre líneas de montaje.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Algoritmo de visión estereo en tiempo real implementado en GPGPU

En el este trabajo se presenta una implementación en tiempo real de un sistema de visión artificial en tres dimensiones sobre GPGPU. Se logra optimizar el procesamiento de visión estéreo mediante el algoritmo de Suma de Diferencias Absolutas (SAD), seleccionado en virtud de su costo computacional moderado. Se aplican sobre la imagen resultante sendos kernels de sustracción de fondo y suavizado, con el objeto de minimizar los errores de procesamiento intrínsecos de SAD, obteniéndose en forma experimental los parámetros óptimos para cada kernel. Se aplica esta cadena de procesamiento sobre una plataforma basada en GPGPU, y sobre un equipo basado en CPU convencional de arquitectura x86. Se comparan los resultados con el mismo procesamiento ejecutado en una CPU convencional y se demuestra una mejora 13x en el tiempo de ejecución, y por consecuencia, la factibilidad de aplicar el método para procesamiento de video en tiempo real utilizando GPGPUs como plataforma de ejecución, hecho que permite proyectar futuros trabajos en aplicaciones industriales de tiempo real que se valgan de la visión 3D para verificación de ensamble de productos sobre líneas de montaje.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Algoritmo de visión estereo en tiempo real implementado en GPGPU

En el este trabajo se presenta una implementación en tiempo real de un sistema de visión artificial en tres dimensiones sobre GPGPU. Se logra optimizar el procesamiento de visión estéreo mediante el algoritmo de Suma de Diferencias Absolutas (SAD), seleccionado en virtud de su costo computacional moderado. Se aplican sobre la imagen resultante sendos kernels de sustracción de fondo y suavizado, con el objeto de minimizar los errores de procesamiento intrínsecos de SAD, obteniéndose en forma experimental los parámetros óptimos para cada kernel. Se aplica esta cadena de procesamiento sobre una plataforma basada en GPGPU, y sobre un equipo basado en CPU convencional de arquitectura x86. Se comparan los resultados con el mismo procesamiento ejecutado en una CPU convencional y se demuestra una mejora 13x en el tiempo de ejecución, y por consecuencia, la factibilidad de aplicar el método para procesamiento de video en tiempo real utilizando GPGPUs como plataforma de ejecución, hecho que permite proyectar futuros trabajos en aplicaciones industriales de tiempo real que se valgan de la visión 3D para verificación de ensamble de productos sobre líneas de montaje.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Peanut stripe virus - a new seed-borne potyvirus from China infecting groundnut (Arachis hypogaea)

A new virus, peanut stripe (PStV), isolated from groundnut (Arachis hypogaea) in the USA, induced characteristic striping, discontinuous vein banding along the lateral veins, and oakleaf mosaic in groundnut. The virus was also isolated from germplasm lines introduced from the People's Republic of China. PStV was transmitted by inoculation of sap to nine species of the Chenopodiaceae, Leguminosae, and Solanaceae; Chenopodium amaranticolor was a good local lesion host. PStV was also transmitted by Aphis craccivora in a non-persistent manner and through seed of groundnut up to 37%. The virus remained infective in buffered plant extracts after diluting to 10-3, storage for 3 days at 20°C, and heating for 10 min at 60°C but not 65°C. Purified virus preparations contained flexuous filamentous particles c. 752 nm long, which contained a major polypeptide of 33 500 daltons and one nucleic acid species of 3·1 × 106 daltons. In ELISA, PStV was serologically related to blackeye cowpea mosaic, soybean mosaic, clover yellow vein, and pepper veinal mottle viruses but not to peanut mottle, potato Y, tobacco etch, and peanut green mosaic viruses. On the basis of these properties PStV is identified as a new potyvirus in groundnut

Search for a periodic signal from Cygnus X-3 usingmuons observed underground in the Frejus detector (4800 mwe)

Periodic signals from Cygnus X-3 in the ultra high energy range were recently reported by air shower arrays and attributed to gamma rays. Although gamma rays are expected to produce muon-poor showers, the preceding observations have stimulated similar studies based on underground muons. Two groups have claimed a significant underground signal coming from Cygnus X-3. The results are, however, extremely difficult to explain in the present framework of particle physics, and clearly need confirmation. The preliminary results obtained from the Frejus underground detector during its first 16 months of operation (March 1984 to June 1985) are presented

Identification and Incidence of Peanut Viruses in Georgia

Surveys of peanuts in Georgia in 1983 detected peanut mottle virus (PMV), peanut stripe virus (PStV), and peanut stunt virus. The mild strain of PMV was by far the most prevalent virus in commercial peanuts; it occurred in every field and an average incidence of 15-20% was observed when the growing season was about two-thirds complete. The necrosis strain of PMV was noted in 39% of the fields, but the incidence was less than 0.1%. A new severe strain of PMV (chlorotic stunt) was identified in two fields. PStV was found at four locations; in each case the infected plants were near peanut germplasm lines from The People's Republic of China. Mixed infections of PMV and PStV occurred frequently. Peanut stunt virus was noted only in one research field in 1983. Numerous serological and sap inoculation tests did not detect tomato spotted wilt virus or cowpea chlorotic mottle viru

Purification and some serological relationships of tomato spotted wilt virus isolates occurring on peanut (Arachis hypogaea) in the USA

A procedure for the purification of TSWV-Tx, a tomato spotted wilt virus isolate infecting groundnuts in Texas, is described. A rabbit antiserum was produced. Several TSWV isolates occurring on groundnuts in the USA reacted to varying extents in ELISA with antisera to TSWV-Tx and to Greek TSWV isolates, but failed to react with antiserum to an isolate of TSWV from India. In reciprocal tests, antigens of the Indian TSWV failed to react with antisera to Tx and to the Greek isolates. Purified TSWV-Tx contained 4 polypeptide species of 78 000, 54 000 and 27 000 Da. In electro-blot immunoassays, all 4 polypeptides reacted with the homologous antiserum and with antisera prepared against a Greek, a Dutch and an Australian isolate. None of the polypeptides reacted with the antiserum to the Indian isolate