Conocimiento de matemáticas y la competencia de reconocer el desarrollo del razonamiento up and down en los estudiantes

El objetivo de este estudio es aportar información sobre el papel que desempeña el conocimiento de matemáticas de los estudiantes para maestro (EPM) cuando piensan en el aprendizaje de las matemáticas de los estudiantes de primaria. Nuestro estudio se centra en el razonamiento up and down que es una de las componentes que facilitan el desarrollo del razonamiento proporcional. 92 EPM resolvieron una tarea en la que tenían que interpretar las respuestas de estudiantes de educación primaria a un problema que implicaba el razonamiento up and down. Identificamos tres perfiles de EPM caracterizados por la relación entre el conocimiento de matemáticas y la competencia de reconocer el desarrollo del razonamiento up and down en los estudiantes.

Cómo reconocen los estudiantes para maestro evidencias del razonamiento up and down en los estudiantes

Este estudio examina cómo los estudiantes para maestro identifican evidencias del razonamiento up and down en los estudiantes de primaria. Este razonamiento implica dos procesos: la reconstrucción de la unidad y la representación de fracciones. 92 estudiantes para maestro respondieron una tarea que consistía en analizar tres respuestas de estudiantes de educación primaria a un problema de proporcionalidad que mostraban diferentes características de esta manera de razonar. En este estudio presentamos algunos aspectos del análisis que estamos realizando para categorizar la manera en la que los estudiantes para maestro reconocen evidencias de este razonamiento, y cómo este reconocimiento se relaciona con la manera en la que reconocen los elementos matemáticos relevantes para resolver el problema.

Up and down the north Pacific coast by canoe and mission ship / by Rev. Thomas Crosby, missionary to the Indians of British Columbia.

http://www.archive.org/details/upanddownnorth00crosrich

Karyotype characterization reveals an up and down of 45S and 5S rDNA sites in Crotalaria (Leguminosae-Papilionoideae) species of the section Hedriocarpae subsection Macrostachyae

The genus Crotalaria is one of the largest within the family Leguminosae-Papilionoideae, with more than 600 species. However, few karyotypes have been described. In the present paper, five species belonging to the section Hedriocarpae were studied (subsection Machrostachyae), in order to better understand chromosomal evolution in Crotalaria. The results reveals that all species presented 2n = 2x = 16 with symmetrical karyotypes, and slight differences in the chromosome morphology. A secondary constriction was identified at short arm of the pair 1. The 45S rDNA was mapped in the secondary constriction and adjacent heterochromatin (NOR-heterochromatin) and a minor site was identified in C. ochroleuca. The 5S rDNA was mapped linked to 45S rDNA at chromosome 1 short arm in all species. Additional sites for 5S rDNA were identified in C. pallida, C. striata and C. mucronata. Heterochromatin blocks around the centromeres are not CMA(+) neither DAPI(+). The karyotypes of the subsection Macrostachyae are characterized by an inversion at chromosome pair one in relation to previous specialized floral species analyzed. Additional sites of 45S and 5S rDNA were assumed to be a result of transposition events by different ways. The results suggest heterochromatin differentiation and the position of ribosomal genes indicates chromosomal rearrangements during evolution. Karyotype characteristics corroborate the morphological infrageneric classification.

On a psychophysical transformed-rule up and down method converging on a 75% level of correct responses

Tranformed-rule up and down psychophysical methods have gained great popularity, mainly because they combine criterion-free responses with an adaptive procedure allowing rapid determination of an average stimulus threshold at various criterion levels of correct responses. The statistical theory underlying the methods now in routine use is based on sets of consecutive responses with assumed constant probabilities of occurrence. The response rules requiring consecutive responses prevent the possibility of using the most desirable response criterion, that of 75% correct responses. The earliest transformed-rule up and down method, whose rules included nonconsecutive responses, did not contain this limitation but failed to become generally accepted, lacking a published theoretical foundation. Such a foundation is provided in this article and is validated empirically with the help of experiments on human subjects and a computer simulation. In addition to allowing the criterion of 75% correct responses, the method is more efficient than the methods excluding nonconsecutive responses in their rules.

Sailing directions for the principal ports in the Bay of Bengal, with remarks upon the winds and currents; and special instructions for making passages up and down the bay.

Mode of access: Internet.

Up and down the Nile; or, Young adventurers in Africa,

Mode of access: Internet.

Up and down,

Mode of access: Internet.

Up and down the Thames, from London Bridge ... to the sea ...

Mode of access: Internet.

Dynamics of economic well-being : income, 1992 to 1993 : moving up and down the income ladder /

Mode of access: Internet.

Taunton's citizens' and travelers' rapid transit map and time table of the Metropolitan and New York elevated railways : showing, on a new plan, the railways with up and down-town tracks ... ferries, etc., etc.

Covers Manhattan south of 62nd Street.