7,949 research outputs found
Luso-African trade and settlement in the Gambia and Guinea-Bissau regions, 16th-19th centuries
African Studies Center Working Paper No. 24This paper examines the economic, social, and cultural influences of Luso-Africans
living along the Gambia River and in the Guinea-Bissau region from the sixteenth
to the nineteenth centuries, in terms of two general themes. The first is
the significance of the sustained economic, social, and cultural ties between the
Cape Verde Islands and the Guinea-Bissau region which began in the fifteenth century,
and which continue to the present day. The second concerns how interrelationships
between African societies, incoming Portuguese and Cape Verdean "strangers," and
their Luso-African descendants changed over time
Comment on What Collective Bargaining Promises and What it Does
[Excerpt] There can be no disagreement with Professor Jensen\u27s position that a belief in freedom is at the heart of our commitment to collective bargaining. These comments are a footnote to what he says about institutional accommodation and freedom in associations. My point is that acceptable institutional accommodation is achieved only when the institutions themselves do, in fact, offer choices to individuals and thus give freedom its essential meaning
Western Africa To c/1860 A.D.: A Provisional Historical Schema Based On Climate Periods
Overview of climate changes and ecological zones and their relation to the history of West Africa
Kola trade and state-building: upper Guinea Coast and Senegambia, 15th - 17th centuries
African Studies Center Working Paper No. 38INTRODUCTION: From earliest recorded times to the present day, no African commodity has
been more important in West African commerce than kola, a product of the
coastal rainforest belt. Kola are highly esteemed as an indulgent and mild
stimulant, are used for medical purposes, as valued presents between friends
and first acquaintances, as symbols in social and religious ceremonies, as
tokens of peace or war (depending on their white or red color) in diplomatic
exchanges between states, and as the source of a distinctive yellow dye for
decorating cloth.
The beginnings of West African inter-regional commerce in kola cannot be
dated. That the savannah populations had a longstanding commerce with the
forest areas is attested by Arabic sources dating kola exports from the
Western Sudan to North Africa from the thirteenth century. 2 In recent years
scholars have contributed much information concerning overland routes
connecting kola-producing areas of Guinea-Conakry, Sierra Leone, Liberia, and
Ghana with interior markets, but there has been no comparable study of
coastwise commerce along the upper Guinea Coast, and for good reason: the
paucity of sources for the period prior to the seventeenth century.... [TRUNCATED
Lactate as a fulcrum of metabolism.
Mistakenly thought to be the consequence of oxygen lack in contracting skeletal muscle we now know that the L-enantiomer of the lactate anion is formed under fully aerobic conditions and is utilized continuously in diverse cells, tissues, organs and at the whole-body level. By shuttling between producer (driver) and consumer (recipient) cells lactate fulfills at least three purposes: 1] a major energy source for mitochondrial respiration; 2] the major gluconeogenic precursor; and 3] a signaling molecule. Working by mass action, cell redox regulation, allosteric binding, and reprogramming of chromatin by lactylation of lysine residues on histones, lactate has major influences in energy substrate partitioning. The physiological range of tissue [lactate] is 0.5-20 mM and the cellular Lactate/Pyruvate ratio (L/P) can range from 10 to >500; these changes during exercise and other stress-strain responses dwarf other metabolic signals in magnitude and span. Hence, lactate dynamics have rapid and major short- and long-term effects on cell redox and other control systems. By inhibiting lipolysis in adipose via HCAR-1, and muscle mitochondrial fatty acid uptake via malonyl-CoA and CPT1, lactate controls energy substrate partitioning. Repeated lactate exposure from regular exercise results in major effects on the expression of regulatory enzymes of glycolysis and mitochondrial respiration. Lactate is the fulcrum of metabolic regulation in vivo
Mathematical models for information processing systems
Ph.D.Joseph J. Mode
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