The construction of the African perspective: a history of the General History of Africa project (Unesco)

This article analyzes the construction of the African perspective in the General History of Africa project (GHA), focusing on the period between 1965 and 1979. With the participation of over two hundred international experts under the auspices of Unesco, this was one of the greatest intellectual projects of the twentieth century. Based on primary sources, this analysis emphasizes the internal conflicts involved in the construction of the African perspective as a hegemonic line of thought in the GHA. Two critical moments of the project were found in the investigation: the controversial years (1972-78), and the pragmatic years (1978-82). As a result of these disputes, theoretical and methodological parameters were constructed, in addition to eight volumes of material published in the 1980s, and recently republished in Brazil.

Catalogue of the type material of Neriidae (Diptera, Schizophora) in the collection of the Museum fur Naturkunde Berlin, Germany

The Diptera collection of the Natural History Museum Berlin holds one of the most important collections of Neriidae. In this paper, the type specimens (holotypes, lectotypes, paratypes, paralectotypes, syntypes) of this historical collection are listed. 28 species-group taxa are dealt with. A lectotype designation is made for the species Brachantichir purpusianus Enderlein, 1922 in order to fix the identity of the name. Holotypes are recognized by monotypy of the species Chaetomeristes bullatus Enderlein, 1922; Chaetomeristes peruanus Enderlein, 1922; Derocephalus angusticollis Enderlein, 1922; Glyphidops limbatus Enderlein, 1922; Longina abdominalis Wiedemann, 1830; Loxozus clavicornis Enderlein, 1922; Oncopsia mexicana Enderlein, 1922; Paranerius fibulatus Enderlein, 1922; Telostylinus dahli Enderlein, 1922; Telostylus latibrachium Enderlein, 1922; and Telostylinus luridus Enderlein, 1922. Syntypes are labelled and listed for Brachantichir robusta Enderlein, 1922; Nerius terebratus Enderlein, 1922; Odontoloxozus punctulatus Enderlein, 1922; Telostylinus apicalis Enderlein, 1922; Telostylinus obscuratus Enderlein, 1922; and Telostylinus ornatipennis Enderlein, 1922. The account concludes with geographic and taxonomic summaries; an appendix listing the abbreviations, localities, and collectors cited in the text; and a bibliography. ((c) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Redundant nerve roots of the cauda equina: review of the literature

In imaging diagnosis, redundant nerve roots of the cauda equina are characterized by the presence of elongated, enlarged and tortuous nerve roots in close relationship with a high-grade lumbar spinal canal stenosis. This is not an independent entity, but it is believed to be a consequence of the chronic compression at the level of the lumbar canal stenosis and thus may be part of the natural history of lumbar spinal stenosis. The present paper is aimed at reviewing the histopathological, electrophysiological and imaging findings, particularly at magnetic resonance imaging, as well as the clinical meaning of this entity. As the current assessment of canal stenosis and root compression is preferably performed by means of magnetic resonance imaging, this is the imaging method by which the condition is identified. The recognition of redundant nerve roots at magnetic resonance imaging is important, particularly to avoid misdiagnosing other conditions such as intradural arteriovenous malformations. The literature approaching the clinical relevance of the presence of redundant nerve roots is controversial. There are articles suggesting that the pathological changes of the nerve roots are irreversible at the moment of diagnosis and therefore neurological symptoms are less likely to improve with surgical decompression, but such concept is not a consensus.

Systematics of the Oswaldoi Complex (Anopheles, Nyssorhynchus) in South America

Abstract Background Effective malaria control relies on accurate identification of those Anopheles mosquitoes responsible for the transmission of Plasmodium parasites. Anopheles oswaldoi s.l. has been incriminated as a malaria vector in Colombia and some localities in Brazil, but not ubiquitously throughout its Neotropical range. This evidence together with variable morphological characters and genetic differences supports that An. oswaldoi s.l. compromises a species complex. The recent fully integrated redescription of An. oswaldoi s.s. provides a solid taxonomic foundation from which to molecularly determine other members of the complex. Methods DNA sequences of the Second Internal Transcribed Spacer (ITS2 - rDNA) (n = 192) and the barcoding region of the Cytochrome Oxidase I gene (COI - mtDNA) (n = 110) were generated from 255 specimens of An. oswaldoi s.l. from 33 localities: Brazil (8 localities, including the lectotype series of An. oswaldoi), Ecuador (4), Colombia (17), Trinidad and Tobago (1), and Peru (3). COI sequences were analyzed employing the Kimura-two-parameter model (K2P), Bayesian analysis (MrBayes), Mixed Yule-Coalescent model (MYC, for delimitation of clusters) and TCS genealogies. Results Separate and combined analysis of the COI and ITS2 data sets unequivocally supported four separate species: two previously determined (An. oswaldoi s.s. and An. oswaldoi B) and two newly designated species in the Oswaldoi Complex (An. oswaldoi A and An. sp. nr. konderi). The COI intra- and inter-specific genetic distances for the four taxa were non-overlapping, averaging 0.012 (0.007 to 0.020) and 0.052 (0.038 to 0.064), respectively. The concurring four clusters delineated by MrBayes and MYC, and four independent TCS networks, strongly confirmed their separate species status. In addition, An. konderi of Sallum should be regarded as unique with respect to the above. Despite initially being included as an outgroup taxon, this species falls well within the examined taxa, suggesting a combined analysis of these taxa would be most appropriate. Conclusions: Through novel data and retrospective comparison of available COI and ITS2 DNA sequences, evidence is shown to support the separate species status of An. oswaldoi s.s., An. oswaldoi A and An. oswaldoi B, and at least two species in the closely related An. konderi complex (An. sp. nr. konderi, An. konderi of Sallum). Although An. oswaldoi s.s. has never been implicated in malaria transmission, An. oswaldoi B is a confirmed vector and the new species An. oswaldoi A and An. sp. nr. konderi are circumstantially implicated, most likely acting as secondary vectors.

Study of the Influence of Localized Vibrational Modes in Charge Transport Properties at Nanoscale Systems.

In molecular and atomic devices the interaction between electrons and ionic vibrations has an important role in electronic transport. The electron-phonon coupling can cause the loss of the electron's phase coherence, the opening of new conductance channels and the suppression of purely elastic ones. From the technological viewpoint phonons might restrict the efficiency of electronic devices by energy dissipation, causing heating, power loss and instability. The state of the art in electron transport calculations consists in combining ab initio calculations via Density Functional Theory (DFT) with Non-Equilibrium Green's Function formalism (NEGF). In order to include electron-phonon interactions, one needs in principle to include a self-energy scattering term in the open system Hamiltonian which takes into account the effect of the phonons over the electrons and vice versa. Nevertheless this term could be obtained approximately by perturbative methods. In the First Born Approximation one considers only the first order terms of the electronic Green's function expansion. In the Self-Consistent Born Approximation, the interaction self-energy is calculated with the perturbed electronic Green's function in a self-consistent way. In this work we describe how to incorporate the electron-phonon interaction to the SMEAGOL program (Spin and Molecular Electronics in Atomically Generated Orbital Landscapes), an ab initio code for electronic transport based on the combination of DFT + NEGF. This provides a tool for calculating the transport properties of materials' specific system, particularly in molecular electronics. Preliminary results will be presented, showing the effects produced by considering the electron-phonon interaction in nanoscale devices.

Between the court and the revolution: the role of one ""merchant"" in America, capital of portuguese Empire

The article discusses the trajectory of Manuel Luis da Veiga which, as a merchant in Portugal (where he was born) invested to install a factory in Pernambuco after the arrival of Real Family in the Rio de Janeiro, considering the changes, in these days, in the Portuguese Empire. It focuses the political sociabilities, remarking the role of Veiga in the court and his writings on political economy, understanding both as two linked dimensions of his social practice. It points out that his trajectory shows a deeply changing world in terms of paradigms, impossible to be understood simply in patterns of what was old or new in the beginning of XIX century.