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In this contribution I shall be interested, among other things, in finding a place for the European phenomenon of the ›Speculum humanae salvationis‹ within German literary history, which will inescapably involve revisiting the unfashionable discussion of date and origins. I also intend to ask about the place of this text in the ‘didactic’ literature of the Middle Ages. Is a religious text structured according to sacred history didactic? Much didactic poetry is in the vernacular: What does it mean that the ›Speculum‹ was composed in Latin? And what place should be accorded to its vernacular reception? The ›Speculum‹ is inscribed within a set of oppositions that would appear to be recurrent in the didactic literature of the later Middle Ages: Latin and vernacular, verse and prose, words and pictures, religious and profane, moral
teaching and devotion, clerical and lay. In view of its exceptionally broad transmission in the German lands, both in Latin and in vernacular reworkings, is it possible to describe this text so that it takes a place within a larger picture? In some respects it may stand at a threshold in the history of European didacticism.
Youth, HIV
(2009)
The five research reports that constitute this monograph are a fruit of the collaboration between the Council for the Development of Social Science Research in African (CODESRIA) and the Social Science Research Council (SSRC), two institutions with a longstanding interest in the study of youth and social transformations in Africa. Under the collaboration, 12 young African researchers were able to benefit from fellowships, workshops and the expertise of resource persons. The studies contribute significant empirical insights from five different countries (Tanzania, Ethiopia, Mozambique, Zimbabwe and Cameroon) to ongoing debates on how youth and social processes in Africa shape, and are shaped, by the HIV/AIDS pandemic.
This meticulous and comprehensive documentation of Cameroonian Youth Day Messages and leadership discourse on youth from 1949 - 2009 is a gold mine for researchers, historians and anyone interested in studying youth, politics and society in Africa. The book presents and explores themes and content of Youth Day Messages: how these messages tied in with, or veered away from, key events and issues of the time; how they served as a platform for West Cameroon governments, and the Ahidjo and Biya regimes to articulate their political vision, justify their policies, sell their respective ideologies to the youth; and what lessons could be drawn from them on competing, conflicting and complementary perspectives on youth agency in Cameroon and Africa. Churchill links the Youth Day to ongoing discussions in Africa about the role and place of youths as agents of development in Africa. Most significantly, he finally puts Cameroon's controversial Youth Day in its appropriate historical context - not as a political device created by the Francophone politicians to distort Cameroonian history and erase 'plebiscite day' from the collective memory as Anglophone nationalists claim, but as a British Cameroons colonial legacy, successfully sold to the Ahidjo regime as a day to be commemorated throughout the federation, by leaders of the federated state of West Cameroon. Churchill Ewumbue-Monono, a senior career diplomat, is Minister Counsellor in the Cameroon Embassy in Moscow. A graduate of the International Higher School of Journalism, and the International Relations Institute of Cameroon in the University of Yaounde, he was a 1991-92 Fellow in Public Diplomacy in Boston University, USA. He has served in Cameroon in various professional capacities. Ewumbue-Monono has written extensively on Cameroon's political history, and his books include Men of Courage, published in 2005.
Youth and Higher Education in Africa : The Cases of Cameroon, South Africa, Eritrea and Zimbabwe
(2009)
Student activism in Africa, at least since the early 1990s, has been preoccupied with popular struggles for democracy in both their respective countries and institutions of higher learning. The changing socio-economic and political conditions in many African countries, characterized by the decline in economic growth and the introduction of multi-party politics, among several other factors, have had different impact on students and student political organizations in African universities. This book recounts the responses of students to these changes in their attempt to negotiate better living and studying conditions. The four case studies contained in the book - Cameroon, South Africa, Zimbabwe and Eritrea - clearly reveal the very important aspects of the situation in which African students find themselves in many countries, and underscores the need to understand the character and development of higher education on the continent. Ministries of Higher Education, Vice Chancellors, Deans of Students, Student Unions and parents will find this book very useful in terms of understanding the tensions that often arise at institutions of higher learning and why solutions seem to be elusive.
Two species of Xyloryctes occur in the United States: X. jamaicensis (Drury) and X. thestalus Bates. Identification and distribution of these species has long been confused but is reviewed and clarified here. Xyloryctes jamaicensis occurs only in the eastern half of the U.S. and not in the southwestern U.S. as previously thought, while X. thestalus occurs in Guatemala and southern Mexico northwards to the southwestern United States. This hypothesis is corroborated by biogeographical and host plant data. Three new synonyms are listed for X. thestalus: X. faunus Casey 1915, X. hebes Casey 1915, and X. thestalus borealis Endrödi. The decline of Fraxinus spp., the food plant of Xyloryctes species, as a result of damage caused by the introduced emerald ash borer (Agrilus planipennis Fairmaire; Buprestidae) in the United States might portend a similar decline for Xyloryctes species in North America.
X-ray structure of the Na+-coupled Glycine-Betaine symporter BetP from Corynebacterium glutamicum
(2009)
Cellular membranes are important sites of interaction between cells and their environment. Among the multitude of macromolecular complexes embedded in these membranes, transporters play a particularly important role. These integral membrane proteins perform a number of vital functions that enable cell adaptation to changing environmental conditions. Osmotic stress is a major external stimulus for cells. Bacteria are frequently exposed to either hyperosmotic or hypoosmotic stress. Typical conditions for soil bacteria, such as Corynebacterium glutamicum, vary between dryness and sudden rainfall. Physical stimuli caused by osmotic stress have to be sensed and used to activate appropriate response mechanisms. Hypoosmotic stress causes immediate and uncontrolled influx of water. Cells counteract by instantly opening mechanosensitive channels, which act as emergency valves leading to fast efflux of small solutes out of the cell, therebydiminishing the osmotic gradient across the cell membrane. Hyperosmotic stress, on the other hand, results in water efflux. This is counterbalanced by an accumulation of small, osmotically active solutes in the cytoplasm, the so-called compatible solutes. They comprise a large variety of substances, including amino acids (proline), amino acid derivatives (betaine, ectoine), oligosaccharides (trehalose), and heterosides (glucosylglycerol). Osmoregulated transporters sense intracellular osmotic pressure and respond to hyperosmotic stress by facilitating the inward translocation of compatible solutes across the cell membrane, to restore normal hydration levels. This work presents the first X-ray structure of a member of the Betaine-Choline-Carnitine-Transporter (BCCT) family, BetP. This Na+-coupled symporter from Corynebacterium glutamicum is a highly effective osmoregulated and specific uptake system for glycine-betaine. X-ray structure determination was achieved using single wavelength anomalous dispersion (SAD) of selenium atoms. Selenium was incorporated into the protein during its expression in methione auxotrophic E. coli cells, grown in media supplemented with selenomethionine. SAD data with anomalous signal up to 5 Å led to the detection of 39 selenium sites, which were used to calculate the initial electron density map of the protein. Medium resolution and high data anisotropy made the structure determination of BetP a challenging task. A specific strategy for data anisotropy correction and a combination of various crystallographic programs were necessary to obtain an interpretable electron density map suitable for model building. The crystal structure of BetP shows a trimer with glycine-betaine bound in a three-fold cation-pi interaction built by conserved tryptophan residues. The bound substrate is occluded from both sides of the membrane and aromatic side chains line its transport pathway. Very interestingly, the structure reveals that the alpha-helical C-terminal domain, for which a chemo- and osmosensory function was elucidated by biochemical methods, interacts with cytoplasmic loops of an adjacent monomer. These unexpected monomer-monomer interactions are thought to be crucial for the activation mechanism of BetP, and a new atomic model combing biochemical results with the crystal structure is proposed. BetP is shown to have the same overall fold as three unrelated Na+-coupled symporters. While these were crystallised in either the outward- or inward-facing conformation, BetP reveals a unique intermediate state, opening new perspectives on the alternating access mechanism of transport.
Background: Wnt signaling controls the balance between stem cell proliferation and differentiation and body patterning throughout development. Previous data demonstrated that non-canonical Wnts (Wnt5a, Wnt11) increased cardiac gene expression of circulating endothelial progenitor cells (EPC) and bone marrow-derived stem cells cultured in vitro. Since previous studies suggested a contribution of the protein kinase C (PKC) family to the Wnt5a-induced signalling, we investigated which PKC isoforms are activated by non-canonical Wnt5a in human EPC. Methodology/Principal Findings: Immunoblot experiments demonstrated that Wnt5a selectively activated the novel PKC isoform, PKC delta, as evidenced by phosphorylation and translocation. In contrast, the classical Ca2+-dependent PKC isoforms, PKC alpha and beta2, and one of the other novel PKC isoforms, PKC epsilon, were not activated by Wnt5a. The PKC delta inhibitor rottlerin significantly blocked co-culture-induced cardiac differentiation in vitro, whereas inhibitors directed against the classical Ca2+-dependent PKC isoforms or a PKC epsilon-inhibitory peptide did not block cardiac differentiation. In accordance, EPC derived from PKC delta heterozygous mice exhibited a significant reduction of Wnt5a-induced cardiac gene expression compared to wild type mice derived EPC. Conclusions/Significance: These data indicate that Wnt5a enhances cardiac gene expressions of EPC via an activation of PKC delta.
The northern plains of Saudi Arabia are an area of approximately 231,000 km2, or roughly equivalent to the size of the whole of the United Kingdom. During previous ABBA Surveys in this area in late winter and spring significant numbers of wintering species such as Dotterel Charadrius morinellus, sandgrouse Pterocles sps and eagles and vultures have been recorded, as well as the threatened Sociable Plover Vanellus gregarius. The main objective of ABBA Survey 40 (30 January - 28 February 2009) was to assess wintering populations of these birds in northern Arabia through sampling methods. In all 21 timed walked censuses in the early morning and 25 driven transect counts (over a total distance of 1511 km) were carried out. Unfortunately most of the region had suffered a severe drought over an extended period, perhaps the previous ten years or longer, and in most of the survey area there had been no rain at all during the winter/spring period of 2008/2009. This lack of rain had resulted in a complete lack of green vegetation in most of the western part of the area studied. Consequently the census results showed low species diversity and small populations.