Nouveau recueil de chants religieux à l'usage du culte Israe͏̈lite : contenant: 96 cantiques, psaumes, hymnes, anciennes récitations à 2, 3 et 4 parties

par S. Naumbourg

The broad-leaf herbicide 2,4-dichlorophenoxyacetic acid turns rice into a living trap for a major insect pest and a parasitic wasp

Synthetic chemical elicitors of plant defense have been touted as a powerful means for sustainable crop protection. Yet, they have never been successfully applied to control insect pests in the field. We developed a high-throughput chemical genetics screening system based on a herbivore-induced linalool synthase promoter fused to a β-glucuronidase (GUS) reporter construct to test synthetic compounds for their potential to induce rice defenses. We identified 2,4-dichlorophenoxyacetic acid (2,4-D), an auxin homolog and widely used herbicide in monocotyledonous crops, as a potent elicitor of rice defenses. Low doses of 2,4-D induced a strong defensive reaction upstream of the jasmonic acid and ethylene pathways, resulting in a marked increase in trypsin proteinase inhibitor activity and volatile production. Induced plants were more resistant to the striped stem borer Chilo suppressalis, but became highly attractive to the brown planthopper Nilaparvata lugens and its main egg parasitoid Anagrus nilaparvatae. In a field experiment, 2,4-D application turned rice plants into living traps for N. lugens by attracting parasitoids. • Our findings demonstrate the potential of auxin homologs as defensive signals and show the potential of the herbicide to turn rice into a selective catch crop for an economically important pest.

Effects of pH, light and temperature on (1→3,1→4)-β-glucanase stability in wheat leaves

Changes in (1→3,1→4)-β-D-glucan endohydrolase (EC 3.2.1.73) protein levels were investigated in segments from second leaves of wheat (Triticum aestivum L.). The abundance of the enzyme protein markedly increased when leaf segments were incubated in the dark whereas the enzyme rapidly disappeared when dark-incubated segments were illuminated or fed with sucrose. Addition of cycloheximide (CHI) to the incubation medium led to the disappearance of previously synthesized (1→3,1→4)-β-glucanase and suppressed the dark-induced accumulation indicating that the enzyme was rather unstable. The degradation of (1→3,1→4)-β-glucanase was analyzed without the interference of de-novo synthesis in intercellular washing fluid (IWF). The loss of the enzyme protein during incubation of IWF (containing naturally present peptide hydrolases) indicated that the stability increased from pH 4 to pH 7 and that an increase in the temperature from 25 to 35 °C considerably decreased the stability. Chelating divalent cations in the IWF with o-phenanthroline also resulted in a lowered stability of the enzyme. A strong temperature effect in the range from 25 to 35 °C was also observed in wheat leaf segments. Diurnal changes in (1→3,1→4)-β-glucanase activity were followed in intact second leaves from young wheat plants. At the end of the dark period, the activity was high but constantly decreased during the light phase and remained low if the light period was extended. Activity returned to the initial level during a 10-h dark phase. During a diurnal cycle, changes in (1→3,1→4)-β-glucanase activity were associated with reciprocal changes in soluble carbohydrates. The results suggest that the synthesis and the proteolytic degradation of an apoplastic enzyme may rapidly respond to changing environmental conditions.

Reversible accumulation of (1→3,1→4)‐β‐glucan endohydrolase in wheat leaves under sugar depletion

A (1→3,1→4)‐β‐D‐glucan endohydrolase [(1→3,1→4)‐β‐glucanase, EC 3.2.1.73] was detected in wheat (Triticum aestivum L.) leaves by Western analyses and activity measurements. This enzyme is able to degrade the (1→3,1→4)‐β‐glucans present in the cell walls of cereals and other grass species. In wheat, enzyme levels clearly increased during leaf development, reaching maximum values at full expansion and then decreasing upon leaf ageing. To test whether the abundance of (1→3,1→4)‐β‐glucanase might be controlled by the carbohydrate status, environmental and nutritional conditions capable of altering the leaf soluble sugar contents were used. Both the activity and enzyme protein levels rapidly and markedly increased when mature leaves were depleted of sugars (e.g. during extended dark periods), whereas elevated carbohydrate contents (e.g. following continuous illumination, glucose supply in the dark or nitrogen deficiency during a light/dark cycle) caused a rapid decrease in (1→3,1→4)‐β‐glucanase abundance or prevented its accumulation in the leaves. The physiological significance of (1→3,1→4)‐β‐glucanase accumulation under sugar depletion remains to be elucidated.

Zur Geschichte der Schulen Palästina's im 3. und 4. Jahrhundert : die Genossen

Wilhelm Bacher

Mus Hs 1537 - [Kantate "Herr Gott, dich loben alle wir] : [BWV 130 ; Arie 3, Rezitativ 4, Arie 5]

[Johann Sebastian Bach]

Las Cooperativas yerbateras entre proyectos estatales en mutación. Misiones (Argentina), 1950-1976. En: LaRivada, V. 3, nº 4

La actual provincia de Misiones desarrolló una economía relacionada a cultivos industriales, particularmente yerba mate y tabaco. El sistema productivo se enlazó a ellos, los cuales además modelaron las explotaciones agrícolas y al sujeto social agrario. El objetivo de este trabajo es analizar las acciones colectivas desplegadas por el cooperativismo yerbatero misionero y la representación de intereses del sector, tomando como referente a la Federación de Cooperativas Agrícolas de Misiones (Fedecoop); las mismas serán puestas en relación con los cambios en las políticas estatales a partir de la década de 1950 hasta 1976. Se sostiene la hipótesis de que las cooperativas promueven una organización económica y social válida para los sujetos rurales del agro misionero. Para este análisis histórico, interesa considerar la construcción de hegemonía, entrelazados con el vínculo existente entre los proyectos productivos y sociales que sostenía el sujeto cooperativo y aquél que el Estado intentó reformular al finalizar el gobierno peronista en 1955. El propósito es ponderar cuáles fueron las consecuencias de los cambios ocurridos a partir del paso de un Estado interventor a uno burocrático autoritario sobre el movimiento cooperativo.

La comunidad educativa ante el desafío de inclusión en el marco de las políticas educativas y sociales y las expectativas de las familias. En: LaRivada, V. 3, nº 4

El presente artículo es el resultado de la articulación del producto de dos investigaciones llevadas a cabo entre los años 2009-2010 y 2011-2013 en la ciudad de Posadas Misiones. En la primera investigación, “Análisis de los efectos de la aplicación de programas compensatorios en las instituciones educativas de Posadas y en las condiciones laborales docentes. Período 2005-2010” se registraron las diferentes representaciones que directivos y docentes tenían acerca de los sujetos de aprendizaje y sus familias lo que motivó a efectuar la segunda investigación, “Importancia que le asignan las familias en condición de pobreza a la educación”, a los efectos de obtener la mirada de las familias en relación a la escuela, docentes y directivos así como sobre los planes sociales.

Educación Intercultural Bilingüe, el desafío en una comunidad Mbya-Guaraní. En: LaRivada, V. 3, nº 4

En el presente artículo proponemos una aproximación al desafío que representa construir una Educación Intercultural Bilingüe en una aldea Mbya Guaraní, Jakutinga (Yacutinga), Municipio de Gobernador Roca, Misiones. Partimos de una introducción a la cuestión educativa para centrarnos luego en la Escuela Provincial N° 659 “Padre Antonio Sepp” donde conviven niños de la aldea Mbya y “criollos” o de la sociedad nacional conformando una escuela de matrícula “mixta”. Muchas de las dimensiones aquí problematizadas se encuentran aún en elaboración, las consideramos introductorias a lo que posteriormente abordaremos en una Tesina de Grado que tratará sobre las relaciones entre los niños indígenas y no indígenas, sus docentes y Auxiliares Docentes Indígenas, el pasaje de la comunidad a la escuela y la implementación de la modalidad E.I.B centrando nuestra mirada en el Nivel Inicial.

CaCO3, foraminifer fragmentation, benthic carbon isotopes, coarse lithic counts and radiogenic isotopes (Sr, Nd, Pb) of the Pliocene and earliest Pleistocene terrigenous component (3.3-2.4 Ma) of IODP Site 306-U1313

We present Plio-Pleistocene records of sediment color, %CaCO3, foraminifer fragmentation, benthic carbon isotopes (d13C) and radiogenic isotopes (Sr, Nd, Pb) of the terrigenous component from IODP Site U1313, a reoccupation of benchmark subtropical North Atlantic Ocean DSDP Site 607. We show that (inter)glacial cycles in sediment color and %CaCO3 pre-date major northern hemisphere glaciation and are unambiguously and consistently correlated to benthic oxygen isotopes back to 3.3 million years ago (Ma) and intermittently so probably back to the Miocene/Pliocene boundary. We show these lithological cycles to be driven by enhanced glacial fluxes of terrigenous material (eolian dust), not carbonate dissolution (the classic interpretation). Our radiogenic isotope data indicate a North American source for this dust (~3.3-2.4 Ma) in keeping with the interpreted source of terrestrial plant wax-derived biomarkers deposited at Site U1313. Yet our data indicate a mid latitude provenance regardless of (inter)glacial state, a finding that is inconsistent with the biomarker-inferred importance of glaciogenic mechanisms of dust production and transport. Moreover, we find that the relation between the biomarker and lithogenic components of dust accumulation is distinctly non-linear. Both records show a jump in glacial rates of accumulation from Marine Isotope Stage, MIS, G6 (2.72 Ma) onwards but the amplitude of this signal is about 3-8 times greater for biomarkers than for dust and particularly extreme during MIS 100 (2.52 Ma). We conclude that North America shifted abruptly to a distinctly more arid glacial regime from MIS G6, but major shifts in glacial North American vegetation biomes and regional wind fields (exacerbated by the growth of a large Laurentide Ice Sheet during MIS 100) likely explain amplification of this signal in the biomarker records. Our findings are consistent with wetter-than-modern reconstructions of North American continental climate under the warm high CO2 conditions of the Early Pliocene but contrast with most model predictions for the response of the hydrological cycle to anthropogenic warming over the coming 50 years (poleward expansion of the subtropical dry zones).