609 research outputs found
1955 Ruby Yearbook
A digitized copy of the 1955 Ruby, the Ursinus College yearbook.https://digitalcommons.ursinus.edu/ruby/1058/thumbnail.jp
The Nature of the Chemical Bond. VII. The Calculation of Resonance Energy in Conjugated Systems
Geochemistry of crustally derived leucocratic igneous rocks from the Ulugh Muztagh Area, Northern Tibet and their implications for the formation of the Tibetan Plateau
This is the published version. Copyright 2012 American Geophysical Union. All Rights Reserved.Igneous rocks collected from the Ulugh Muztagh, 200 km south of the northern rim of the Tibetan Plateau (36°28âČN, 87°29âČE), form intrusive and extrusive bodies whose magmas were produced by partial melting of upper-crustal, primarily pelitic, source rocks. Evidence for source composition includes high initial 87Sr/86Sr ratios (âŒ0.711 to 0.713), 206Pb/204Pb ratios of 18.72, 207Pb/204Pb of 15.63 and 208Pb/204Pb of 38.73. The degree of melting in the source region was increased by significant heating via in situ decay of radioactive nuclides; a reasonable estimate for the heat production rate in the source is 3.9Ă10â6 W/m3. The crystallization ages and cooling ages [Burchfiel et al., 1989] of the earliest intrusive rocks within the suite suggest crustal thickening began in the northern Tibetan Plateau before 10.5 Ma, with maximum average unroofing rates in this part of the Tibetan Plateau for the period between 10.5 and 4 Ma at approximately < 2 mm/yr. The Ulugh Muztagh flows are at the northern edge of a widely distributed field of Plio-pliestocene volcanic rocks in the north-central Tibetan Plateau. The crustally derived rocks described here are an endmember component of a wide mixing zone of hybrid magmas; the other end-member forms mantle-derived, potassic basanites and tephrites exposed in the central section of the Plio-Pleistocene field. The compositional trends in these belts strike east-west, at high angle to the N30E strike of the Plateau itself. Consideration of the chemical data and published geophysical data argue that the sub-Plateau mantle is mechanically detached from the overlying continental lithosphĂšre, and that in this section of the plateau the thermal structure of the asthenosphere is not responsible for the formation or maintenance of the plateau's topography
Major flaws in conflict prevention policies towards Africa : the conceptual deficits of international actorsâ approaches and how to overcome them
Current thinking on African conflicts suffers from misinterpretations oversimplification, lack of focus, lack of conceptual clarity, state-centrism and lack of vision). The paper analyses a variety of the dominant explanations of major international actors and donors, showing how these frequently do not distinguish with sufficient clarity between the âroot causesâ of a conflict, its aggravating factors and its triggers. Specifically, a correct assessment of conflict prolonging (or sustaining) factors is of vital importance in Africaâs lingering confrontations. Broader approaches (e.g. âstructural stabilityâ) offer a better analytical framework than familiar one-dimensional explanations. Moreover, for explaining and dealing with violent conflicts a shift of attention from the nation-state towards the local and sub-regional level is needed.Aktuelle Analysen afrikanischer Gewaltkonflikte sind hĂ€ufig voller Fehlinterpretationen (Mangel an Differenzierung, Genauigkeit und konzeptioneller Klarheit, Staatszentriertheit, fehlende mittelfristige Zielvorstellungen). Breitere AnsĂ€tze (z. B. das Modell der Strukturellen StabilitĂ€t) könnten die Grundlage fĂŒr bessere Analyseraster und Politiken sein als eindimensionale ErklĂ€rungen. hĂ€ufig differenzieren ErklĂ€rungsansĂ€tze nicht mit ausreichender Klarheit zwischen Ursachen, verschĂ€rfenden und auslösenden Faktoren. Insbesondere die richtige Einordnung konfliktverlĂ€ngernder Faktoren ist in den jahrzehntelangen gewaltsamen Auseinandersetzungen in Afrika von zentraler Bedeutung. Das Diskussionspapier stellt die groĂe Variationsbreite dominanter ErklĂ€rungsmuster der wichtigsten internationalen Geber und Akteure gegenĂŒber und fordert einen Perspektivenwechsel zum Einbezug der lokalen und der subregionalen Ebene fĂŒr die ErklĂ€rung und Bearbeitung gewaltsamer Konflikte
From âUnilateralâ to âDialogicalâ: Determinants of EUâAzerbaijan Negotiations
The European Union (EU) and Azerbaijan have negotiated three different agreements for a new legal basis underpinning their relationship since 2010. Whereas the EU tries to adhere to a more unilateral approach, Azerbaijan wants cooperation to take place on a more inclusive, dialogical, basis. The essay will present a model of âbargaining powerâ to analyse how the Azerbaijani government has tried to enforce this, and to what degree it has been successful. It finds that the bargaining power model can explain some of the changing power dynamics in EUâAzerbaijan relations, and that these might speak to the broader Eurasian region too
From domestic to regional: The civil war conundrum and the cases of Syria and Algeria
This paper seeks to answer a simple question: When do regional powers get involved in civil wars? Some civil wars see a significant involvement of regional actors, while others show a remarkable level of isolation. What explains this difference? This research answers this question by looking at two case studies: the Algerian civil war (1991â2002) and the Syrian civil war (2011âup to date). The paper identifies and develops five factors of regional involvement. These are: capabilities, regional dynamics, countryâs relevance, regional security issues/containment and domesticâexternal links. civil wars are today one of the most prominent and deadly forms of conflict, and this paper contributes to understanding the important but understudied issue of regional involvement.N/
Wealthiest is Not Always Healthiest: What Explains Differences in Child Mortality in West Africa?
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