Der lehrreiche Moment oder Das erhabene Werkzeug in Gottes Händen : Rede, bei Gelegenheit der, von der Gemeinde zu Posen am ... 4. Aug. 1844, Abends, in der grossen Synagoge abgehaltenen Dankfeier für die Erhaltung Sr. Königlichen Majestät

von Salomon Plessner

El Camino de Paikín: un acercamiento a los grupos mocoví del Chaco a través del tratado de 1774. En: Avá, nº 13

En 1774 y dentro de un programa que intentaba establecer paces con los grupos indígenas del Chaco se produjo el encuentro entre Jerónimo Matorras, gobernador del Tucumán y Paikín, líder Mocoví. Este encuentro, que tuvo lugar dentro del territorio chaqueño, dio lugar a la firma de un tratado que buscaba regular las relaciones entre ciertos grupos indígenas y el sector colonial La publicación de este tratado en varias obras de recopilación desde principios del siglo XX ayudó a crear una imagen acerca del comienzo del dominio político y territorial de los indígenas por parte de la sociedad hispanocriolla. En el presente trabajo proponemos releer el tratado de 1774 dentro del conjunto mayor de fuentes que se produjeron en torno a estas negociaciones para adentrarnos en las estrategias y prácticas políticas desplegadas, la modificación de las relaciones de alianza y enemistad y las condiciones de posibilidad de acción de cada uno de los sectores implicados.

Horizontal profiles of longwave and shortwave radiation components over sea ice near Barrow, Alaska during the 2011 melt

An integrated instrument package for measuring and understanding the surface radiation budget of sea ice is presented, along with results from its first deployment. The setup simultaneously measures broadband fluxes of upwelling and downwelling terrestrial and solar radiation (four components separately), spectral fluxes of incident and reflected solar radiation, and supporting data such as air temperature and humidity, surface temperature, and location (GPS), in addition to photographing the sky and observed surface during each measurement. The instruments are mounted on a small sled, allowing measurements of the radiation budget to be made at many locations in the study area to see the effect of small-scale surface processes on the large-scale radiation budget. Such observations have many applications, from calibration and validation of remote sensing products to improving our understanding of surface processes that affect atmosphere-snow-ice interactions and drive feedbacks, ultimately leading to the potential to improve climate modelling of ice-covered regions of the ocean. The photographs, spectral data, and other observations allow for improved analysis of the broadband data. An example of this is shown by using the observations made during a partly cloudy day, which show erratic variations due to passing clouds, and creating a careful estimate of what the radiation budget along the observed line would have been under uniform sky conditions, clear or overcast. Other data from the setup's first deployment, in June 2011 on fast ice near Point Barrow, Alaska, are also shown; these illustrate the rapid changes of the radiation budget during a cold period that led to refreezing and new snow well into the melt season.