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We present an original anisotropic stress-dependent rock physics model for the organic rich shales of the Inoceramus formation, the main source rock and unconventional reservoir in the Austral Basin, Argentina. We implement a novel combination of anisotropic poroelastic theories which take into account organic matter content, lithologic description, fluid type, saturation and stress state. In this approach, we model the infill as a mixture of solid organic matter and interconnected pore fluids, using total organic carbon analysis and petrophysical data from two wells. The compliance of the matrix is considered to be stress-dependent following the porosity deformation approach (PDA). The elasticity and density of the multiminerallic saturated rock is obtained using the mineral fractions obtained from X-ray diffraction information, porosity analysis and fluid properties. This allows us to compute synthetic acoustic velocities. The calibration of the model also involved the inversion of several unknowns (the set of PDA parameters, clays and kerogen physical properties) by minimizing the misfit between modelled and ultrasonic measured velocities. Due to the lack of oblique velocity data, to complete the compliance tensor, a static-to-dynamic ratio was built for each sample, and constant anellipticity was assumed with increasing stress. The model calibrated with this innovative procedure demonstrated its usefulness to predict stiffness, compliance, and compressional and shear wave velocity variations under variable applied stress. It is also useful for the estimation of stress-related changes of porosity and Biot's effective stress coefficients, which can be difficult to measure in shales, and therefore there are few values reported in the literature. [ABSTRACT FROM AUTHOR]

Clerodendrum bungei Steud. is confirmed for the Argentinean Flora, cited before without reference material. A brief description of the species, field photos and comments on its geographical distribution and ecology are presented. In addition, a key to the adventitious and native species of Clerodendrum in Argentina is provided. [ABSTRACT FROM AUTHOR]

Echinodorus australis Rataj, a species from southern Brazil and northern Argentina, is here synonymized under Helanthium bolivianum (Rusby) Lehtonen & Myllys. [ABSTRACT FROM AUTHOR]

As part of the taxonomic revision of the family Vitaceae for the Argentinean Flora, a new combination, Clematicissus pruinata (Weinm.) C. A. Zanotti & A. M. Panizza, is established as the correct name for the taxon known up to now as C. simsiana (Roem. & Schult.) Lombardi. [ABSTRACT FROM AUTHOR]

The present study aimed at the molecular detection of Anaplasma spp. in different samples obtained from cattle, goats and free-living Rhipicephalus microplus ticks from Argentina. DNA of members of the Anaplasmataceae family was detected by different PCR assays. The phylogenetic analyses of the obtained partial DNA sequences of the 16 S rDNA gene resulted in the identification of two different Anaplasma spp.: (I) Anaplasma platys -like bacteria (in blood sample from cattle and pools of R. microplus larvae and (II) Candidatus Anaplasma boleense (in blood samples from goats and one pool of R. microplus larvae of R. microplus). Candidatus A. boleense was found in two provinces that belong to different biogeographic regions, which leads to the conclusion that this bacterium may be widely distributed in Argentina. Interestingly, both Anaplasma spp. were found in the same R. microplus population in Chaco province, indicating that these two strains of Anaplasma are circulating in the same tick population. The results of this work represent the first report of the circulation of A. platys -like bacteria and Ca. A. boleense in domestic ruminants and free-living R. microplus ticks in Argentina. Further studies to determine the prevalence of infection, dispersion, clinical impact, transmission routes and cross-reactivity in serological tests of both Anaplasma species are needed. • Samples from the North of Argentina were tested for Anaplasma spp. DNA. • Anaplasma platys -like bacteria and Candidatus A. boleense were detected. • Candidatus A. boleense seems to be widely distributed in Argentina. • Both Anaplasma spp. were found in the same R. microplus population in Chaco province. • The circulation of these species in domestic ruminants and R. microplus is reported for the first time in Argentina. [ABSTRACT FROM AUTHOR]

The article seeks to add to the growing contribution of discursive approaches to the study of political institutions by analysing the possibilities for cross-fertilisation between discursive institutionalism and post-structuralist discourse theory. Analysing Vivien Schmidt's version of discursive institutionalism, it argues that Schmidt's concept of discourse results in a model of explanation of institutional change that overlooks questions about the relations between power, politics and discourse. It further argues that while post-structural discourse theory has made important contributions to the understanding of the discursive nature of social practices, it has so far failed fully to take on board the institutional dimension of politics. It concludes that an integration of Schmidt's insights on discursive institutionalism with post-structuralist discourse theory allows a more rounded analysis of the political dimension of institutions and of the institutional dimension of politics, as well as a better understanding of institutional change. To illustrate our arguments we draw on our own research to analyse the relations between discourse and institutions in the 2002 presidential electoral campaign in Brazil and in Argentina's poverty reduction policies in the 1990s. [ABSTRACT FROM AUTHOR]

The idea of an area of endemism implies that different groups of plants and animals should have largely coincident distributions. This paper analyses an area of 1152 000 km2, between parallels 21 and 32°S and meridians 70 and 53°W to examine whether a large and taxonomically diverse data set actually displays areas supported by different groups. The data set includes the distribution of 805 species of plants (45 families), mammals (25 families), reptiles (six families), amphibians (five families), birds (18 families), and insects (30 families), and is analysed with the optimality criterion (based on the notion of endemism) implemented in the program NDM/VNDM. Almost 50% of the areas obtained are supported by three or more major groups; areas supported by fewer major groups generally contain species from different genera, families, or orders. © The Willi Hennig Society 2011. [ABSTRACT FROM AUTHOR]

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This section presents a photo-essay which records four protest demonstrations held over a week at the Plaza de Mayo in Buenos Aires, Argentina, in August 2008.

This paper analyzes the distribution of vascular plants species endemic to the southern central Andes (south-western Bolivia and north-western Argentina). All 540 species endemic to the study regions (approx. 720600 km²) have been included in the analysis. The main part of the endemic species is found in semiarid habitats between 1500-3500 m asl pointing to the topographically complex plateau, slope, and valley system of the southern central Andes as the main locations for its endemic flora. The distribution of the endemic species within arid sites is in contrast with that of vascular plant diversity in general, as the most diverse habitat of the region is the moist subtropical Tucumano-Bolivian Yungas forest of the eastern Andes slope. A total of 17 well defined and partly overlapping distribution patterns were indentified. The broadest distribution pattern defines a general area of endemism for the southern central Andes. This area extends through nearly the entire region and is defined by species that are widespread within the region in desert to sub-humid environments of the high Andes, slopes, or valleys. Nearly all other areas of endemism are nested within this broad distribution pattern as successively north-south overlapping areas along the slopes and valleys of the Andes and the Pampeanas Range. Despite the distributional bias of endemism towards the arid sites almost half of the endemic species are restricted to a few high endemic areas that lie in juxtaposition to the main rainfall zones. These areas contain the widest habitat ranges in terms of altitude and rainfall within the region with the endemic species being equally variable in altitude and moisture requirements. Previous defined phytogeographic units were not recognized among the distribution patterns. However, the northern part of the Prepuna can be defined as two partly overlapping distribution patterns. [ABSTRACT FROM AUTHOR]