Age determinations and analyses of organic matter of sediments from the Argentine Basin

The first radiocarbon chronology for sediments of the Argentine basin has been determined using accelerator mass spectrometer (AMS) analyses of 54 total organic carbon samples from four box and two piston cores collected from the downstream and upstream sides of two central Argentine Basin mudwaves. Throughout the Holocene, sediment from the geomorphically defined upstream side of each wave accumulated at rates of 30 to 105 cm/1000 years. Sediments from the downstream side of each wave accumulated at rates of 2 to 10 cm/1000 years in the late and early Holocene, while the mid Holocene is characterized by sedimentation rates less than 1.0 cm/1000 years. During the mid-Holocene, increased aridity reduced chemical weathering and the flow of the rivers draining to the continental shelf, causing a concomitant decrease in fine-grained terrigenous input to the basin as evidenced by decreased sedimentation rates, lower N/C ratios, and depleted delta13Corg values. It is estimated that all of the organic carbon deposited in the central basin during the mid-Holocene was of a marine origin. During the late and early Holocene, however, approximately 35% of the organic carbon deposited was of terrestrial origin. Bottom water flow speeds in the late Holocene were estimated using a lee-wave model and found to average 14 cm/s. This estimate is comparable to 10 cm/s mean and 15-20 cm/s maximum flow speeds measured by current meters deployed within the basin. Flow speeds in the Argentine Basin were 10% higher than today from 8000 to 2000 B.P., and are consistent with a general invigoration of thermohaline circulation that began between 9000 and 8000 B.P. It is proposed that the introduction of warm, salty Indian Ocean water into the northern North Atlantic at 9000 B.P. was the mechanism that provided the excess salt needed to stabilize the North Atlantic Deep Water thermohaline circulation system in its present mode.

Pore water and solid phase sulfur, carbon and iron data from samples collected in the Argentine Basin during expedition M78

Sulfur phases in the Argentine Basin.

Age and growth parameters of skates of the genus Bathyraja obtained between 2003-2005 along the Argentine continental shelf

In the last 20 years directed shark and ray fishery has increased alarmingly everywhere in the world. For most species though, no data on growth rate, mortality, fecundity and other life history aspects exist as of now and management of the fishery is therefore insufficient. Also there still exist methodological difficulties in the age determination of elasmobranchs fishes, a fact which complicates the investigation of growth parameters. This study tried to identify the best ageing methods and estimate growth parameters for ten skate species of the genus Bathyraja, all occurring in the southwest Atlantic in depths of 50m and more. 720 samples were collected on board of argentine research vessels in between 2003 and 2005. Crystal violet and a new staining method using potassium permanganate, both applied on sagittal sections of vertebral centra, proved to be most effective in enhancing the banding pattern in most of the species. Thorns were also tested and readings were consistent with the ones made on vertebral sections. Growth parameters could be derived for six species and for the other four estimates could be made. Growth rate as well as infinite length varied between species, with those attaining bigger sizes having lower growth rates. No latitudinal differences in growth rate could be detected but a comparison with samples from other studies showed that total lengths were always reported to be higher around the Malvinas Islands.

Transformation and continuity of the Argentine welfare state -- evaluating social security reform in the 1990s

Beginning after World War II, Argentina institutionalized a limited conservative corporatist welfare state where occupation-linked social insurance held a central position and social assistance had a residual character. This was called a limited conservative corporatist welfare state, because the huge population within the informal sector was excluded from the main system. A populist government supported by trade unions and the economic model of import-substituting industrialization were the background for the formation of this type of welfare state. During the 1990s, elements of a liberal regime were added to the Argentine welfare state under the reform carried out by the Menem Peronist government. However, social insurance reform and labor reform were not as drastic as the economic reform. They still retained a certain continuity from the traditional systems. The government intended to carry out more drastic social security and labor reform, but was unable to do so due to the legacy of corporatism of the Peronist government.

Les débats parlementaires autour du suffrage universel dans la construction de la représentation politique en Espagne et en Argentine: vers une analyse comparée (1860-1870)

This article aims to undertake a preliminary comparative review of the concepts of political representation developed by the Spanish and Argentinean liberalism during the construction of the parliamentary and constitutional regimes in the nineteenth century. The idea of the representative government, as a regulatory mechanism of political participation, is considered in terms of an analysis of the right to vote, of the processes to develop citizenship, and of political modernization. Legislation on the right to vote, born as the political right par excellence during the nineteenth century, gives an excellent guide to these political processes of major scope and depth that characterize the contemporary world. The comparison between the Spanish and Argentinean cases shows that exchanges, transfers of legislative models and cultural movements took place in the birth of the concept of political representation in both countries. This enables us to identify the differences of in each case.