THE ROLE OF THE GEOGRAPHER IN DEVELOPMENT SURVEYS, WITH EXAMPLES FROM THE SOUTH AMERICAN TROPICS

The Puna-Altiplano plateau represents a regionally significant dust source, which is critically located at the nexus between the tropical and sub-polar synoptic systems that dominate the South American climate. Dust emissions in this region would therefore be expected to be sensitive to changes in these systems, in particular the strength and position of the South American Summer Monsoon (SASM). Here, we present a late-Holocene multi-proxy study where changes in dust flux, reconstructed from a high-altitude peat mire, are examined in light of climate variability and human impacts. Results show that for most the 4300 cal. yr BP record, dust flux sensitively tracked changes in SASM activity. Prior to 2600 cal. yr BP relatively high dust flux implies dry conditions prevailed across the Puna-Altiplao in association with reduced SASM activity. The chemistry of dust deposited at this time matched the large endorheic basins on the Puna, which host ephemeral lakes and terminal fans, indicating these were actively supplying dust to the airstream. After 2600 cal. yr BP, SASM activity increased while dust flux decreased and the dust chemistry changed, collectively implying the shutting down of the Puna-Altiplano as a significant dust source. Dust flux increased after 1000 cal. yr BP during the ‘Medieval Warm Period’, associated with a return to drier conditions and reactivation of dust sources across the endorheic basins of the Puna. Natural variability in dust flux was dwarfed, however, by the very significant increase in flux after 400 cal. yr BP following Spanish Colonisation and associated changing landuse practices. This finding attests to the globally significant role of humans on dust emissions.

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Israeli penetration in South America (1973-1947)

Journal Ishraqat Tanmawya ◽

10.51424/ishq.26.1 ◽

2021 ◽

Vol 26 ◽

pp. 1-23

Keyword(s):

South America ◽

Key Words ◽

Decision Makers ◽

The Political ◽

South American ◽

American Continent ◽

The South ◽

Political Decision ◽

South American Continent

This research is an attempt to uncover the reality and method of Israeli penetration in the South American continent, and aims to draw attention to the weaknesses and mistakes in the role of Arab communities that they had to play in South America, and the position of Arab governments towards that continent. The research was divided into two main axes, as the first dealt with the means of Israeli penetration in South America until 1947, providing a brief overview of the roots of the penetration in the South American continent and the methods it adopted in achieving this. While the second axis focused on the stance of the South American countries on the Arab-Israeli conflict (1947-1973). However, the Israeli infiltration was affecting the political decision-makers in that continent towards the decision to partition Palestine up to the October 1973 war. Key words: the penetration, Palestine, Israel, immigration, Arabs, America

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The role of the vascular endothelium in arenavirus haemorrhagic fevers

Thrombosis and Haemostasis ◽

10.1160/th09-06-0357 ◽

2009 ◽

Vol 102 (12) ◽

pp. 1024-1029 ◽

Cited By ~ 27

Author(s):

Stefan Kunz

Keyword(s):

Vascular Endothelium ◽

Cell Function ◽

Experimental Studies ◽

Lassa Fever ◽

Vascular Involvement ◽

Lassa Virus ◽

South American ◽

The South ◽

Endothelial Cell Function

SummaryViral haemorrhagic fevers (VHF) caused by arenaviruses are among the most devastating emerging human diseases.The most important pathogen among the arenaviruses is Lassa virus (LASV), the causative agent of Lassa fever that is endemic to West Africa. On the South American continent, the New World arenavirus Junin virus (JUNV), Machupo (MACV), Guanarito (GTOV), and Sabia virus (SABV) have emerged as causative agents of severe VHFs. Clinical and experimental studies on arenavirus VHF have revealed a crucial role of the endothelium in their pathogenesis. However, in contrast to other VHFs, haemorrhages are not a salient feature of Lassa fever and fatal cases do not show overt destruction of vascular tissue.The functional alteration of the vascular endothelium that precede shock and death in fatal Lassa fever may be due to more subtle direct or indirect effects of the virus on endothelial cells. Haemorrhagic disease manifestations and vascular involvement are more pronounced in the VHF caused by the South American haemorrhagic fever viruses. Recent studies on JUNV revealed perturbation of specific endothelial cell function, including expression of cell adhesion molecules, coagulation factors, and vasoactive mediators as a consequence of productive viral infection.These studies provided first possible links to some of the vascular abnormalities observed in patients; however, their relevance in vivo remains to be investigated.

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Ameryka Łacińska w polityce zagranicznej Brazylii – niedokończony projekt przywództwa regionalnego

100-lecie polskiej Policji - Studia Politologiczne ◽

10.33896/spolit.2020.55.21 ◽

2020 ◽

Vol 2020 (55) ◽

pp. 425-439

Author(s):

Anita Oberda Monkiewicz

Keyword(s):

Foreign Policy ◽

Latin America ◽

South American ◽

The South ◽

Important Place ◽

Regional Leadership

The purpose of the article is to discuss the place and role of Latin America in Brazil’s foreign policy. The article leads to the conclusion that, starting from the 1990s, Latin America, a region that was marginalized for many years, gained an important place in Brazilian policy. The construction of the South American community has become an instrument of strengthening regional leadership, although due to the lack of a coherent strategy towards the direct neighbourhood, it proved to be short-lived.

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EVOLUÇÃO DA ICTIOFAUNA DE RIACHOS SUL-AMERICANOS (CASTRO, 1999) REVISITADO APÓS MAIS DE DUAS DÉCADAS

Oecologia Australis ◽

10.4257/oeco.2021.2502.02 ◽

2021 ◽

Vol 25 (02) ◽

pp. 231-245

Author(s):

Ricardo Macedo Corrêa e Castro ◽

Keyword(s):

Maximum Size ◽

Taxonomic Diversity ◽

Respiratory Physiology ◽

South American ◽

Adult Size ◽

The South ◽

Evolutionary Pattern ◽

The Family ◽

Respective Species

A little more than 20 years after the first publication of Castro (1999), the knowledge of the South American freshwater ichthyofauna, especially that of Brazil, has increased dramatically. This increase occurred both in terms of knowledge of its taxonomic diversity - in 1999, based on various sources in the scientific literature, a total of 2,800 species of South American freshwater fish was estimated, and a total of near 3,500 species it is currently known from Brazil alone - as to the knowledge of its evolution and also ecology. Consequently, all the hypotheses originally proposed in that paper are reexamined and critically discussed here considering this new knowledge accumulated in the past nearly two decades. Although the original 1999 hypothesis that the small adult size of their respective species is a general evolutionary pattern shared by the South American stream ichthyofauna has been firmly corroborated by several studies carried out in many regions of Brazil, the different patterns associated with most of the species of stream fish originally proposed are discussed in this chapter in the light of the new accumulated knowledge about their biology and ecology. Likewise, the possible role of heterochrony in their respective evolution is critically analyzed in the context of the great advance that has occurred in understanding the phylogenetic relationships of component taxa of freshwater neotropical ichthyofauna, using mainly the family Characidae as a possible model. Finally, a recent intriguing idea of the role of respiratory physiology in determining both the maximum size of teleost fish and their patterns of environmental occupation is examined in relation to its possible effect in the evolution of South American stream ichthyofauna.

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