Calvin Liu measuring mangrove tree heights, Shark River Slough

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

Left to right: Edward Castaneda, Calvin Liu, Peter Lenaker, and Sharon Ewe after sampling mangrove forest, Shark River Slough

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

Left to right: Sharon Ewe and Calvin Liu applying Florida Bay sediments to dwarf mangrove forest as part of a fertilization experiment, Taylor Slough

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

Calvin Liu measuring mangrove tree heights, Shark River Slough

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

Left to right: Sharon Ewe and Calvin Liu applying Florida Bay sediments to dwarf mangrove forest as part of a fertilization experiment, Taylor Slough

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

Victoria Land Antarctica Pb and Ba concentrations and Pb isotope ratios 1872-1994 CE

Pb and Ba concentrations and Pb isotopic compositions are reported for firn core and snow pit samples from Victoria Land, Antarctica, dating from 1872 AD to 1994 AD. From variations in Pb/Ba ratios and Pb isotopic compositions, two periods of major Pb enhancements were identified, from 1891 to 1908 AD and from 1948 to 1994 AD. The earlier pollution event is attributed to Pb emissions from non-ferrous metal production and coal combustion in the Southern Hemisphere and is in excellent agreement with coincident pollution inputs reported in firn/ice cores from two other regions of Antarctica, at Coats Land and Law Dome. Using Pb isotopic systematics, it was calculated that ~50% of Pb deposited in Victoria Land in 1897 originated from anthropogenic emission sources. The more recent period of Pb enhancements, from 1948 to 1994 AD, corresponds to the introduction and widespread use of gasoline alkyl Pb additives in automobiles in the Southern Hemisphere, with anthropogenic Pb inputs averaging 60% of total Pb but with large uncertainty. Intra- and inter-annual variations in Pb concentrations and isotopic compositions were evaluated in snow pits samples corresponding to the period 1991-1994. Substantial variations in Pb/ Ba and 206Pb/207Pb ratios were detected but the absence of a regular seasonal pattern for these parameters suggests that the transport and deposition of aerosols to the Antarctic ice sheet are complex and vary from year to year.

La publicidad, herramienta promocional del centro de anuncios Roldós y Compañía (1872-1900)

El nacimiento de los primeros centros de anuncios en España data de la segunda mitad del siglo XIX. Uno de ellos es Roldós y Compañía. En un período en el que la publicidad es una actividad incipiente, los primeros profesionales recurren a lo que mejor saben hacer para darse a conocer: anuncios. A través del estudio de la autopublicidad de esta agencia realizada durante las últimas décadas del siglo XIX no solo veremos el progresivo desarrollo de este tipo de piezas (formal y de contenidos) sino también la evolución de todos los agentes que participan en la actividad: agencia, anunciantes y medios de comunicación. En este contexto, el centro de anuncios hace las veces de anunciante y de agencia. Es decir, ejerce una triple función: es el emisor del mensaje y es, a la vez, quien lo confecciona y quien gestiona su inserción en los medios. La historia de la publicidad se escribe junto a la agencia Roldós y Compañía. Por tanto su autopublicidad es un fiel reflejo de todo cuanto ha ocurrido en España desde el nacimiento de la profesión hasta finales del siglo XIX, un período caracterizado por la frecuente presencia de este tipo de anuncios en la prensa escrita del momento.

The Formation of a Liberal Thinker: Georg Jellinek and his Early Writings (1872 – 1878)

Georg Jellinek is known as one of the most prominent representative of German legal positivism. This article aims at identifying and discussing the more theoretical- political connotation of Jellinek’s thought with a particular focus on his liberal inspiration. According to the perspective of the history of political thought, this article shows how some intellectual premises to Jellinek’s liberalism take shape and emerge from a series of young Jellinek’s writings on history of philosophy and history of ideas.