Molecular Genetic Characterization of Endemic Yellow Catfish, Horab rus brachysoma (Gunther)

The present study Molecular genetic characterization of endemic yellow catfish ,generated an important information on the genetic variation and stock structure of the endangered yellow catfish(Horabagrus brachysoma) endemic to the western Ghats. Three genetically discrete stocks of the species have been identified for the first time using allozymes, RAPD(Random Amplified Polymorphic DNA) and microsatelite markers and it is a significant step towards realizing the goal of management of fishery and conservation of the yellow catfish populations in the rivers of the Western Ghats region. In conclusion genetic markers were found to be powerful tools to analyze the population genetic structure of the yellow catfish. Geographic isolation by land distance,inbreading as a result of over-exploitation etc are some reasons for the genetic differenciation between the pairs and deficiency of hetrozygosity revealed by the two co dominant markers, allozyme, and microsatelites.the study emphasizes the need for stock-wise, propagation assisted-rehabilitation of the natural populations yellow catfish

Números naturales (I) : cardinal.

Este vídeo forma parte de un curso completo de matemáticas para EGB

La educación en valores : propuesta didáctica en La clé sur la porte de Marie Cardinal.

Resumen tomado de la publicación

Aprendizaje del cardinal numérico : conflicto cognitivo y cambio conceptual microgenético.

Facilitar, por medio de un proceso de aprendizaje, el paso en los niños del nivel cuarto (aplicación mecánica de la regla del último numeral) al nivel seis (donde se da una auténtica respuesta de cardinal numérico), es decir, se pretende producir un cambio conceptual microgenético desde una perspectiva constructivista. Participan 48 alumnos de nivel cuarto, divididos en dos grupos de 24 (12 niños y 12 niñas respectivamente) asignados al azar: el grupo experimental y el grupo de control. A cada niño del grupo experimetal se le presenta a lo largo de cuatro sesiones de aprendizaje, cuatro pruebas que para resolverlas correctamente debe dar una respuesta de cardinal numérico. El procedimiento consiste en enfrentar al niño a situaciones que le provoquen un conflicto cognitivo al tener que aplicar distintas secuencias de numerales sobre el mismo conjunto de objetos. El instructor interacciona con el niño o niña hasta que éste/a resuelve el conflicto. Se pasa un pretest al inicio de la investigación y dos postest con un mes de diferencia, a ambos grupos, para determinar si se produce o no el cambio conceptual. Los resultados concluyen que las diferencias entre ambos grupos son estadísticamente significativas. Por lo tanto, se produce una evolución en la adquisición de una auténtica respuesta de cardinal numérico en el grupo experimental gracias a las sesiones de aprendizaje.

Red, black, yellow, Peter, John, Mary...

Alumnos y alumnas de tres años empiezan a aprender un idioma nuevo en las aulas. Esta enseñanza de idiomas desde edades tempranas se manifiesta como la mejor fórmula para favorecer el aprendizaje de una lengua extranjera, en un ambiente donde los más pequeños sienten el placer de escuchar y practicar, aprendiendo a través del juego.

La ense??anza del n??mero cardinal y ordinal en Educaci??n infantil

Resumen basado en el de la publicaci??n

Analysis of red and yellow ochre samples from Clearwell Caves and Catalhoyuk by vibrational spectroscopy and other techniques

Ochre samples excavated from the neolithic site at Qatalhoyuk, Turkey have been compared with "native" ochres from Clearwell Caves, UK using infrared spectroscopy backed up by Raman spectroscopy, scanning electron microscopy (with energy-dispersive X-rays (EDX) analysis), powder X-ray diffraction, diffuse reflection UV-Vis and atomic absorption spectroscopies. For the Clearwell Caves ochres, which range in colour from yellow-orange to red-brown, it is shown that the colour is related to the nature of the chromophore present and not to any differences in particle size. The darker red ochres contain predominantly haematite while the yellow ochre contains only goethite. The ochres from Qatalhoyuk contain only about one-twentieth of the levels of iron found in the Clearwell Caves ochres. The iron oxide pigment (haematite in all cases studied here) has been mixed with a soft lime plaster which also contains calcite and silicate (clay) minerals. (C) 2003 Elsevier B.V. All rights reserved.

Simultaneous observations of reconnection pulses at Cluster and their effects on the cusp aurora seen at Chinese Yellow River Station

While the Cluster spacecraft were located near the high-latitude magnetopause, between 10:10 and 10:40 UT on 16 January 2004, three typical flux transfer event (FTE) signatures were observed. During this interval, simultaneous and conjugated all-sky camera measurements, recorded at Yellow River Station, Svalbard, are available at 630.0 and 557.7nm that show poleward-moving auroral forms (PMAFs), consistent with magnetic reconnection at dayside magnetopause. Simultaneous FTEs seen at the magnetopause mainly move northward, but having duskward (eastward) and tailward velocity components, roughly consistent with the observed direction of motion of the PMAFs in all-sky images. Between the PMAFs meridional keograms, extracted from the all-sky images, show intervals of lower intensity aurora which migrate equatorward just before the PMAFs intensify. This is strong evidence for an equatorward eroding and poleward moving open-closed boundary (OCB) associated with a variable magnetopause reconnection rate under variable IMF conditions. From the durations of the PMAFs we infer that the evolution time of FTEs is 5-11 minutes from its origin on magnetopause to its addition to the polar cap.

Disease-weather relationships for powdery mildew and yellow rust on winter wheat

Key weather factors determining the occurrence and severity of powdery mildew and yellow rust epidemics on winter wheat were identified. Empirical models were formulated to qualitatively predict a damaging epidemic (>5% severity) and quantitatively predict the disease severity given a damaging epidemic occurred. The disease data used was from field experiments at 12 locations in the UK covering the period from 1994 to 2002 with matching data from weather stations within a 5 km range. Wind in December to February was the most influential factor for a damaging epidemic of powdery mildew. Disease severity was best identified by a model with temperature, humidity, and rain in April to June. For yellow rust, the temperature in February to June was the most influential factor for a damaging epidemic as well as for disease severity. The qualitative models identified favorable circumstances for damaging epidemics, but damaging epidemics did not always occur in such circumstances, probably due to other factors such as the availability of initial inoculum and cultivar resistance.

Interactions between the grasses Phalaris arundinacea, Miscanthus sinensis and Echinochloa crus-galli, and barley and cereal yellow dwarf virusus

The grass species Miscanthus sinensis, Echinochloa crus-galli and Phalaris arundinacea may be useful biomass crops. In glasshouse inoculations with two isolates of Barley yellow dwarf virus (BYDV)-MAV and BYDV-PAV and one of Cereal yellow dwarf virus (CYVD)-RPV , E. crus galli was infected by all three virus isolates, P. arundinacea by BYDV-MAV and CYDV-RPV, but M. sinensis only by BYDV-MAV. All three hosts became very difficult to infect after several weeks’ growth. Symptoms were inconspicuous; dry matter yield losses ranged from c. 20–40%. Aphids acquired all three virus isolates from E. crus-galli, but more efficiently from 5 than 26-week-old plants. Only BYDV-MAV was acquired from P. arundinacea and M. sinensis. Plants of each species and of Avena sativa were grown outdoors between May and July in 1994 and 1995. Young plants of each species were exposed for successive 2-week intervals during the same periods. Vector populations were higher on A. sativa and P. arundinacea than on E. crus-galli and M. sinensis, and more plants of these species became infected. In 1994 only BYDV-MAV was detected. In 1995 BYDV-MAV, BYDV-PAV and CYDV-RPV were all detected; BYDV-MAV was again the virus isolate most frequently found.

Savory peptides present in Moromi obtained from soy sauce fermentation of yellow soybean

The presence of savory peptides in moromi has been investigated. Moromi was prepared by fermenting yellow soybean using Aspergillus oryzae as the starter at the first step (mold fermentation) and 20% brine solution at the next step (brine fermentation). The moromi was then ultrafiltered stepwise using membranes with MW cut-offs of 10,000, 3,000, and 500 Da, respectively. The fraction with MW < 500 Da was chromatographed using Sephadex G-25 SF to yield four fractions, 1-4. Analysis of soluble peptides, NaCl content, alpha-amino nitrogen, amino acid composition, peptide profile using CE coupled with DAD, taste profile and free glutamic acid content, were performed for each fraction. Fraction 2 contained a relatively high total glutamic acid content, but a relatively low free glutamic acid content and had the highest umami taste. This fraction also had more peptides containing non-aromatic amino acids than the other fractions. The peptides present in fraction 2 may play a role, at least in part, in its intense umami taste.

Analysis of red and yellow ochre samples from Clearwell Caves and Catalhoyuk by vibrational spectroscopy and other techniques

Ochre samples excavated from the neolithic site at Qatalhoyuk, Turkey have been compared with "native" ochres from Clearwell Caves, UK using infrared spectroscopy backed up by Raman spectroscopy, scanning electron microscopy (with energy-dispersive X-rays (EDX) analysis), powder X-ray diffraction, diffuse reflection UV-Vis and atomic absorption spectroscopies. For the Clearwell Caves ochres, which range in colour from yellow-orange to red-brown, it is shown that the colour is related to the nature of the chromophore present and not to any differences in particle size. The darker red ochres contain predominantly haematite while the yellow ochre contains only goethite. The ochres from Qatalhoyuk contain only about one-twentieth of the levels of iron found in the Clearwell Caves ochres. The iron oxide pigment (haematite in all cases studied here) has been mixed with a soft lime plaster which also contains calcite and silicate (clay) minerals. (C) 2003 Elsevier B.V. All rights reserved.