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Sample records for african slave trade

  1. Yellow fever, Asia and the East African slave trade.

    PubMed

    Cathey, John T; Marr, John S

    2014-05-01

    Yellow fever is endemic in parts of sub-Saharan Africa and South America, yet its principal vectors--species of mosquito of the genus Aedes--are found throughout tropical and subtropical latitudes. Phylogenetic analyses indicate that yellow fever originated in Africa and that its spread to the New World coincided with the slave trade, but why yellow fever has never appeared in Asia remains a mystery. None of several previously proposed explanations for its absence there is considered satisfactory. We contrast the trans-Atlantic slave trade, and trade across the Sahara and to the Arabian Peninsula and Mesopotamia, with that to Far East and Southeast Asian ports before abolition of the African slave trade, and before the scientific community understood the transmission vector of yellow fever and the viral life cycle, and the need for shipboard mosquito control. We propose that these differences in slave trading had a primary role in the avoidance of yellow fever transmission into Asia in the centuries before the 20(th) century. The relatively small volume of the Black African slave trade between Africa and East and Southeast Asia has heretofore been largely ignored. Although focal epidemics may have occurred, the volume was insufficient to reach the threshold for endemicity.

  2. The African diaspora: mitochondrial DNA and the Atlantic slave trade.

    PubMed

    Salas, Antonio; Richards, Martin; Lareu, María-Victoria; Scozzari, Rosaria; Coppa, Alfredo; Torroni, Antonio; Macaulay, Vincent; Carracedo, Angel

    2004-03-01

    Between the 15th and 19th centuries ad, the Atlantic slave trade resulted in the forced movement of approximately 13 million people from Africa, mainly to the Americas. Only approximately 11 million survived the passage, and many more died in the early years of captivity. We have studied 481 mitochondrial DNAs (mtDNAs) of recent African ancestry in the Americas and in Eurasia, in an attempt to trace them back to particular regions of Africa. Our results show that mtDNAs in America and Eurasia can, in many cases, be traced to broad geographical regions within Africa, largely in accordance with historical evidence, and raise the possibility that a greater resolution may be possible in the future. However, they also indicate that, at least for the moment, considerable caution is warranted when assessing claims to be able to trace the ancestry of particular lineages to a particular locality within modern-day Africa.

  3. The African Diaspora: Mitochondrial DNA and the Atlantic Slave Trade

    PubMed Central

    Salas, Antonio; Richards, Martin; Lareu, María-Victoria; Scozzari, Rosaria; Coppa, Alfredo; Torroni, Antonio; Macaulay, Vincent; Carracedo, Ángel

    2004-01-01

    Between the 15th and 19th centuries ad, the Atlantic slave trade resulted in the forced movement of ∼13 million people from Africa, mainly to the Americas. Only ∼11 million survived the passage, and many more died in the early years of captivity. We have studied 481 mitochondrial DNAs (mtDNAs) of recent African ancestry in the Americas and in Eurasia, in an attempt to trace them back to particular regions of Africa. Our results show that mtDNAs in America and Eurasia can, in many cases, be traced to broad geographical regions within Africa, largely in accordance with historical evidence, and raise the possibility that a greater resolution may be possible in the future. However, they also indicate that, at least for the moment, considerable caution is warranted when assessing claims to be able to trace the ancestry of particular lineages to a particular locality within modern-day Africa. PMID:14872407

  4. Genetic Evidence of African Slavery at the Beginning of the Trans-Atlantic Slave Trade

    PubMed Central

    Martiniano, Rui; Coelho, Catarina; Ferreira, Maria Teresa; Neves, Maria João; Pinhasi, Ron; Bradley, Daniel G.

    2014-01-01

    An archaeological excavation in Valle da Gafaria (Lagos, Portugal), revealed two contiguous burial places outside the medieval city walls, dating from the 15th–17th centuries AD: one was interpreted as a Leprosarium cemetery and the second as an urban discard deposit, where signs of violent, unceremonious burials suggested that these remains may belong to slaves captured in Africa by the Portuguese. We obtained random short autosomal sequence reads from seven individuals: two from the latter site and five from the Leprosarium and used these to call SNP identities and estimate ancestral affinities with modern reference data. The Leprosarium site samples were less preserved but gave some probability of both African and European ancestry. The two discard deposit burials each gave African affinity signals, which were further refined toward modern West African or Bantu genotyped samples. These data from distressed burials illustrate an African contribution to a low status stratum of Lagos society at a time when this port became a hub of the European trade in African slaves which formed a precursor to the transatlantic transfer of millions. PMID:25104065

  5. Genetic evidence of African slavery at the beginning of the trans-Atlantic slave trade.

    PubMed

    Martiniano, Rui; Coelho, Catarina; Ferreira, Maria Teresa; Neves, Maria João; Pinhasi, Ron; Bradley, Daniel G

    2014-08-08

    An archaeological excavation in Valle da Gafaria (Lagos, Portugal), revealed two contiguous burial places outside the medieval city walls, dating from the 15(th)-17(th) centuries AD: one was interpreted as a Leprosarium cemetery and the second as an urban discard deposit, where signs of violent, unceremonious burials suggested that these remains may belong to slaves captured in Africa by the Portuguese. We obtained random short autosomal sequence reads from seven individuals: two from the latter site and five from the Leprosarium and used these to call SNP identities and estimate ancestral affinities with modern reference data. The Leprosarium site samples were less preserved but gave some probability of both African and European ancestry. The two discard deposit burials each gave African affinity signals, which were further refined toward modern West African or Bantu genotyped samples. These data from distressed burials illustrate an African contribution to a low status stratum of Lagos society at a time when this port became a hub of the European trade in African slaves which formed a precursor to the transatlantic transfer of millions.

  6. The imprint of the Slave Trade in an African American population: mitochondrial DNA, Y chromosome and HTLV-1 analysis in the Noir Marron of French Guiana

    PubMed Central

    2010-01-01

    Background Retracing the genetic histories of the descendant populations of the Slave Trade (16th-19th centuries) is particularly challenging due to the diversity of African ethnic groups involved and the different hybridisation processes with Europeans and Amerindians, which have blurred their original genetic inheritances. The Noir Marron in French Guiana are the direct descendants of maroons who escaped from Dutch plantations in the current day Surinam. They represent an original ethnic group with a highly blended culture. Uniparental markers (mtDNA and NRY) coupled with HTLV-1 sequences (env and LTR) were studied to establish the genetic relationships linking them to African American and African populations. Results All genetic systems presented a high conservation of the African gene pool (African ancestry: mtDNA = 99.3%; NRY = 97.6%; HTLV-1 env = 20/23; HTLV-1 LTR = 6/8). Neither founder effect nor genetic drift was detected and the genetic diversity is within a range commonly observed in Africa. Higher genetic similarities were observed with the populations inhabiting the Bight of Benin (from Ivory Coast to Benin). Other ancestries were identified but they presented an interesting sex-bias. Whilst male origins spread throughout the north of the bight (from Benin to Senegal), female origins were spread throughout the south (from the Ivory Coast to Angola). Conclusions The Noir Marron are unique in having conserved their African genetic ancestry, despite major cultural exchanges with Amerindians and Europeans through inhabiting the same region for four centuries. Their maroon identity and the important number of slaves deported in this region have maintained the original African diversity. All these characteristics permit to identify a major origin located in the former region of the Gold Coast and the Bight of Benin; regions highly impacted by slavery, from which goes a sex-biased longitudinal gradient of ancestry. PMID:20958967

  7. Phylogeography of the human mitochondrial haplogroup L3e: a snapshot of African prehistory and Atlantic slave trade.

    PubMed

    Bandelt, H J; Alves-Silva, J; Guimarães, P E; Santos, M S; Brehm, A; Pereira, L; Coppa, A; Larruga, J M; Rengo, C; Scozzari, R; Torroni, A; Prata, M J; Amorim, A; Prado, V F; Pena, S D

    2001-11-01

    The mtDNA haplogroup L3e, which is identified by the restriction site +2349 MboI within the Afro-Eurasian superhaplogroup L3 (-3592 HpaI), is omnipresent in Africa but virtually absent in Eurasia (except for neighbouring areas with limited genetic exchange). L3e was hitherto poorly characterised in terms of HVS-I motifs, as the ancestral HVS-I type of L3e cannot be distinguished from the putative HVS-I ancestor of the entire L3 (differing from the CRS by a transition at np 16223). An MboI screening at np 2349 of a large number of Brazilian and Caribbean mtDNAs (encompassing numerous mtDNAs of African ancestry), now reveals that L3e is subdivided into four principal clades, each characterised by a single mutation in HVS-I, with additional support coming from HVS-II and partial RFLP analysis. The apparently oldest of these clades (transition at np 16327) occurs mainly in central Africa and was probably carried to southern Africa with the Bantu expansion(s). The most frequent clade (transition at np 16320) testifies to a pronounced expansion event in the mid-Holocene and seems to be prominent in many Bantu groups from all of Africa. In contrast, one clade (transition at np 16264) is essentially restricted to Atlantic western Africa (including Cabo Verde). We propose a tentative L3e phylogeny that is based on 197 HVS-I sequences. We conclude that haplogroup L3e originated in central or eastern Africa about 46,000 (+/-14,000) years ago, and was a hitchhiker of much later dispersal and local expansion events, with the rise of food production and iron smelting. Enforced migration of African slaves to the Americas translocated L3e mitochondria, the descendants of which in Brazil and the Caribbean still reflect their different regional African ancestries.

  8. The Transatlantic Slave Trade and American Slavery.

    ERIC Educational Resources Information Center

    Bucy, Ellen

    2003-01-01

    Provides a collection of Web sites useful for teaching about slavery in the United States and the transatlantic slave trade. States that some Web sites include access to primary sources on slavery while others offer teaching materials on the topic. (CMK)

  9. Middle Passage in the Triangular Slave Trade: The West Indies

    ERIC Educational Resources Information Center

    Sawh, Ruth; Scales, Alice M.

    2006-01-01

    Our narrative focuses on the middle passage of the slave trade in the West Indies. Herein we describe why more men, women, and children were imported in the West Indies than other islands. Specifically, our aim was to address how slaves in the middle passage of the triangular slave trade were treated, how they sustained themselves, and how they…

  10. MtDNA haplogroup analysis of black Brazilian and sub-Saharan populations: implications for the Atlantic slave trade.

    PubMed

    Silva, Wilson Araújo; Bortolini, Maria Cátira; Schneider, Maria Paula Cruz; Marrero, Andrea; Elion, Jacques; Krishnamoorthy, Rajagopal; Zago, Marco Antonio

    2006-02-01

    Seventy individuals from two African and four black Brazilian populations were studied for the first hypervariable segment of mtDNA. To delineate a more complete phylogeographic scenario of the African mtDNA haplogroups in Brazil and to provide additional information on the nature of the Atlantic slave trade, we analyzed our data together with previously published data. The results indicate different sources of African slaves for the four major Brazilian regions. In addition, the data revealed patterns that differ from those expected on the basis of historical registers, thus suggesting the role of ethnic sex differences in the slave trade.

  11. The Atlantic Slave Trade--The Full Story

    ERIC Educational Resources Information Center

    Stern, Sheldon M.

    2005-01-01

    Slavery and slave trading have been part of human history since ancient times. All peoples, races, regions, and religions have at one time or another participated in human slavery. Historian Sheldon M. Stern has found, however, that state U.S. history standards, curricula, and the media often promote the divisive misconception that slavery was…

  12. The Genomic Legacy of the Transatlantic Slave Trade in the Yungas Valley of Bolivia.

    PubMed

    Heinz, Tanja; Cárdenas, Jorge Mario; Álvarez-Iglesias, Vanesa; Pardo-Seco, Jacobo; Gómez-Carballa, Alberto; Santos, Carla; Taboada-Echalar, Patricia; Martinón-Torres, Federico; Salas, Antonio

    2015-01-01

    During the period of the Transatlantic Slave Trade (TAST) some enslaved Africans were forced to move to Upper Peru (nowadays Bolivia). At first they were sent to Potosí, but later to the tropical Yungas valley where the Spanish colonizers established a so-called "hacienda system" that was based on slave labor, including African-descendants. Due to their isolation, very little attention has been paid so far to 'Afro-Bolivian' communities either within the research field of TAST or in genetic population studies. In this study, a total of 105 individuals from the Yungas were sequenced for their mitochondrial DNA (mtDNA) control region, and mitogenomes were obtained for a selected subset of these samples. We also genotyped 46 Ancestry Informative Markers (AIM) in order to investigate continental ancestry at the autosomal level. In addition, Y-chromosome STR and SNP data for a subset of the same individuals was also available from the literature. The data indicate that the partitioning of mtDNA ancestry in the Yungas differs significantly from that in the rest of the country: 81% Native American, 18% African, and 1% European. Interestingly, the great majority of 'Afro-descendant' mtDNA haplotypes in the Yungas (84%) concentrates in the locality of Tocaña. This high proportion of African ancestry in the Tocaña is also manifested in the Y-chromosome (44%) and in the autosomes (56%). In sharp contrast with previous studies on the TAST, the ancestry of about 1/3 of the 'Afro-Bolivian' mtDNA haplotypes can be traced back to East and South East Africa, which may be at least partially explained by the Arab slave trade connected to the TAST.

  13. The Genomic Legacy of the Transatlantic Slave Trade in the Yungas Valley of Bolivia

    PubMed Central

    Cárdenas, Jorge Mario; Álvarez-Iglesias, Vanesa; Pardo-Seco, Jacobo; Gómez-Carballa, Alberto; Santos, Carla; Taboada-Echalar, Patricia; Martinón-Torres, Federico

    2015-01-01

    During the period of the Transatlantic Slave Trade (TAST) some enslaved Africans were forced to move to Upper Peru (nowadays Bolivia). At first they were sent to Potosí, but later to the tropical Yungas valley where the Spanish colonizers established a so-called “hacienda system” that was based on slave labor, including African-descendants. Due to their isolation, very little attention has been paid so far to ‘Afro-Bolivian’ communities either within the research field of TAST or in genetic population studies. In this study, a total of 105 individuals from the Yungas were sequenced for their mitochondrial DNA (mtDNA) control region, and mitogenomes were obtained for a selected subset of these samples. We also genotyped 46 Ancestry Informative Markers (AIM) in order to investigate continental ancestry at the autosomal level. In addition, Y-chromosome STR and SNP data for a subset of the same individuals was also available from the literature. The data indicate that the partitioning of mtDNA ancestry in the Yungas differs significantly from that in the rest of the country: 81% Native American, 18% African, and 1% European. Interestingly, the great majority of ‘Afro-descendant’ mtDNA haplotypes in the Yungas (84%) concentrates in the locality of Tocaña. This high proportion of African ancestry in the Tocaña is also manifested in the Y-chromosome (44%) and in the autosomes (56%). In sharp contrast with previous studies on the TAST, the ancestry of about 1/3 of the ‘Afro-Bolivian’ mtDNA haplotypes can be traced back to East and South East Africa, which may be at least partially explained by the Arab slave trade connected to the TAST. PMID:26263179

  14. Russia's Literary Genius Alexander Pushkin: The Great-Grandson of an African Slave.

    ERIC Educational Resources Information Center

    Lounsbery, Anne

    2000-01-01

    Alexander Pushkin, Russia's most celebrated literary figure, descended from an African slave. On both parents' sides, he was related to Avram Petrovich Gannibal, who was born to an African prince and abducted to become a slave to a Russian diplomat. Pushkin chose to pride himself on both his aristocratic life and his African ancestry. (SM)

  15. The genetic diversity of three peculiar populations descending from the slave trade: Gm study of Noir Marron from French Guiana.

    PubMed

    Brucato, Nicolas; Tortevoye, Patricia; Plancoulaine, Sabine; Guitard, Evelyne; Sanchez-Mazas, Alicia; Larrouy, Georges; Gessain, Antoine; Dugoujon, Jean-Michel

    2009-10-01

    The Noir Marron communities are the direct descendants of African slaves brought to the Guianas during the four centuries (16th to 19th) of the Atlantic slave trade. Among them, three major ethnic groups have been studied: the Aluku, the Ndjuka and the Saramaka. Their history led them to share close relationships with Europeans and Amerindians, as largely documented in their cultural records. The study of Gm polymorphisms of immunoglobulins may help to estimate the amount of gene flow linked to these cultural exchanges. Surprisingly, very low levels of European contribution (2.6%) and Amerindian contribution (1.7%) are detected in the Noir Marron gene pool. On the other hand, an African contribution of 95.7% redraws their origin to West Africa (F(ST) < or = 0.15). This highly preserved African gene pool of the Noir Marron is unique in comparison to other African American populations of Latin America, who are notably more admixed.

  16. Home-grown slaves: women, reproduction, and the abolition of the slave trade, Jamaica 1788-1807.

    PubMed

    Turner, Sasha

    2011-01-01

    Once the British transatlantic slave trade came under abolitionists' scrutiny in 1788, West Indian slaveholders had to consider alternative methods of obtaining well-needed laborers. This article examines changes in enslaved women's working lives as planters sought to increase birth rates to replenish declining laboring populations. By focusing more on variances in work assignment and degrees of punishment rather than their absence, this article establishes that enslaved women in Jamaica experienced a considerable shift in their work responsibilities and their subjection to discipline as slaveholders sought to capitalize on their abilities to reproduce. Enslaved women's reproductive capabilities were pivotal for slavery and the plantation economy's survival once legal supplies from Africa were discontinued.

  17. Native American Y chromosomes in Polynesia: the genetic impact of the Polynesian slave trade.

    PubMed

    Hurles, Matthew E; Maund, Emma; Nicholson, Jane; Bosch, Elena; Renfrew, Colin; Sykes, Bryan C; Jobling, Mark A

    2003-05-01

    Since Thor Heyerdahl asserted that Polynesia was first colonized from the Americas (Heyerdahl 1950), geneticists have sought--but have not found--any evidence to support his theories. Here, Native American Y chromosomes are detected on the Polynesian island of Rapa. However, this, together with other odd features of the island's Y-chromosomal gene pool, is best explained as the genetic impact of a 19th century Peruvian slave trade in Polynesia. These findings underscore the need to account for history before turning to prehistory and the value of archival research to understanding modern genetic diversity. Although the impact of the Atlantic slave trade on the distribution of modern genetic diversity has been well appreciated, this represents the first study investigating the impact of this underappreciated episode on genetic diversity in the Pacific.

  18. Surgeon James Ramsay, 1733-1789: the Navy and the slave trade.

    PubMed Central

    Watt, J

    1994-01-01

    The end of the American War of Independence in 1783 coincided with two very different, but closely related initiatives: the settlement of New South Wales and the fight against the slave trade. In both, James Ramsay, a naval surgeon, played a decisive role. James Ramsay was born on 25 July 1733 at Fraserburgh on the Aberdeenshire coast. After a grammar school education, he was apprenticed to a Dr Findlay, surgeon and physician in Fraserburgh. Through his proficiency in Latin, he obtained a small bursary which enabled him to enter King's College in the University of Aberdeen and brought Ramsay under the influence of Dr Thomas Reid, the professor of moral philosophy, who exercised a profound influence on Ramsay's thinking (Vol 17, pp 632-3). PMID:7853310

  19. [Antonio de Saldanha da Gama's proposals to improve the slave trade "for humanitarian and economic reasons," Rio de Janeiro, 1810].

    PubMed

    Viotti, Ana Carolina de Carvalho

    2016-01-01

    In 1808, Dom João VI issued an edict which regulated the shipping and treatment of slaves on the transatlantic crossing from Africa. Two years later, Antonio de Saldanha da Gama, a member of the Treasury Council, drafted a letter discussing some points of the resolution. This key figure in the Portuguese administration of Brazil argued that his respectful considerations concerning the determinations of His Royal Highness were designed to improve them "for humanitarian and economic reasons." Safeguarded in the archives of Arquivo Histórico Ultramarino, this letter is transcribed, annotated, and contextualized here, supplying an interesting perspective on the prevailing concerns and justifications about the trafficking of African slaves to Brazil.

  20. France: Africans and the French Revolution.

    ERIC Educational Resources Information Center

    Fatunde, Tunde

    1989-01-01

    The French Revolution had profound and long-term effects for Africans, both in Africa and throughout the Western hemisphere. Revolutionary leaders not only opposed the emancipation of slaves in French territories but supported an intensified slave trade, sparking numerous rebellions. French exploitation of Africans extended well into the twentieth…

  1. Consequences of the trans-Atlantic slave trade on medicinal plant selection: plant use for cultural bound syndromes affecting children in Suriname and Western Africa.

    PubMed

    Vossen, Tessa; Towns, Alexandra; Ruysschaert, Sofie; Quiroz, Diana; van Andel, Tinde

    2014-01-01

    Folk perceptions of health and illness include cultural bound syndromes (CBS), ailments generally confined to certain cultural groups or geographic regions and often treated with medicinal plants. Our aim was to compare definitions and plant use for CBS regarding child health in the context of the largest migration in recent human history: the trans-Atlantic slave trade. We compared definitions of four CBS (walk early, evil eye, atita and fontanels) and associated plant use among three Afro-Surinamese populations and their African ancestor groups in Ghana, Bénin and Gabon. We expected plant use to be similar on species level, and assumed the majority to be weedy or domesticated species, as these occur on both continents and were probably recognized by enslaved Africans. Data were obtained by identifying plants mentioned during interviews with local women from the six different populations. To analyse differences and similarities in plant use we used Detrended Component Analysis (DCA) and a Wald Chi-square test. Definitions of the four cultural bound syndromes were roughly the same on both continents. In total, 324 plant species were used. There was little overlap between Suriname and Africa: 15 species were used on two continents, of which seven species were used for the same CBS. Correspondence on family level was much higher. Surinamese populations used significantly more weedy species than Africans, but equal percentages of domesticated plants. Our data indicate that Afro-Surinamers have searched for similar plants to treat their CBS as they remembered from Africa. In some cases, they have found the same species, but they had to reinvent the largest part of their herbal pharmacopeia to treat their CBS using known plant families or trying out new species. Ideas on health and illness appear to be more resilient than the use of plants to treat them.

  2. Consequences of the Trans-Atlantic Slave Trade on Medicinal Plant Selection: Plant Use for Cultural Bound Syndromes Affecting Children in Suriname and Western Africa

    PubMed Central

    Vossen, Tessa; Towns, Alexandra; Ruysschaert, Sofie; Quiroz, Diana; van Andel, Tinde

    2014-01-01

    Folk perceptions of health and illness include cultural bound syndromes (CBS), ailments generally confined to certain cultural groups or geographic regions and often treated with medicinal plants. Our aim was to compare definitions and plant use for CBS regarding child health in the context of the largest migration in recent human history: the trans-Atlantic slave trade. We compared definitions of four CBS (walk early, evil eye, atita and fontanels) and associated plant use among three Afro-Surinamese populations and their African ancestor groups in Ghana, Bénin and Gabon. We expected plant use to be similar on species level, and assumed the majority to be weedy or domesticated species, as these occur on both continents and were probably recognized by enslaved Africans. Data were obtained by identifying plants mentioned during interviews with local women from the six different populations. To analyse differences and similarities in plant use we used Detrended Component Analysis (DCA) and a Wald Chi-square test. Definitions of the four cultural bound syndromes were roughly the same on both continents. In total, 324 plant species were used. There was little overlap between Suriname and Africa: 15 species were used on two continents, of which seven species were used for the same CBS. Correspondence on family level was much higher. Surinamese populations used significantly more weedy species than Africans, but equal percentages of domesticated plants. Our data indicate that Afro-Surinamers have searched for similar plants to treat their CBS as they remembered from Africa. In some cases, they have found the same species, but they had to reinvent the largest part of their herbal pharmacopeia to treat their CBS using known plant families or trying out new species. Ideas on health and illness appear to be more resilient than the use of plants to treat them. PMID:25372485

  3. Slaves No More: The Caring Power of African-American Female Leaders

    ERIC Educational Resources Information Center

    Sernak, Kathleen S.

    2004-01-01

    In this article the author examines the historical significance of the cultural aspect of race on African American females' leadership values and styles that encourage caring in schools. The author focuses her study by asking: What aspects of their (African American female leaders) cultural backgrounds as Africans and as African Americans…

  4. The African Diaspora: Using the Multivalent Theory to Understand Slave Autobiographies

    ERIC Educational Resources Information Center

    Morehouse, Maggi M.

    2007-01-01

    In simple terms, diaspora can be defined as the identity community that is formed when people move. Although the term African Diaspora seems relatively new, a number of 20th century scholars have utilized a diasporic framework to explain the commonalities among people of African descent around the world. The earliest scholars did not use the term;…

  5. Runaway Slave Advertisements: Teaching from Primary Documents

    ERIC Educational Resources Information Center

    Costa, Tom; Doyle, Brooke

    2004-01-01

    In this article, the authors discuss how children can learn from runaway slave advertisements. The advertisements for runaway slaves that masters placed in eighteenth- and nineteenth-century newspapers are among the documentary sources available to teachers for studying the lives of African-American slaves. Such advertisements often describe a…

  6. Constituting Antebellum African American Identity: Resistance, Violence, and Masculinity in Henry Highland Garnet's (1843) "Address to the Slaves"

    ERIC Educational Resources Information Center

    Jasinski, James

    2007-01-01

    In August 1843 Presbyterian minister Henry Highland Garnet delivered his "Address to the Slaves of the United States of America" to the National Convention of Colored Citizens in Buffalo, NY. While often read (and almost as often dismissed) as either an unqualified call for a violent slave rebellion or, at the least, a celebration of…

  7. The African diaspora: history, adaptation and health.

    PubMed

    Rotimi, Charles N; Tekola-Ayele, Fasil; Baker, Jennifer L; Shriner, Daniel

    2016-12-01

    The trans-Atlantic slave trade brought millions of Africans to the New World. Advances in genomics are providing novel insights into the history and health of Africans and the diasporan populations. Recent examples reviewed here include the unraveling of substantial hunter-gatherer and 'Eurasian' admixtures across sub-Saharan Africa, expanding our understanding of ancestral African genetics; the global ubiquity of mixed ancestry; the revealing of African ancestry in Latin Americans that likely derived from the slave trade; and understanding of the ancestral backgrounds of APOL1 and LPL found to influence kidney disease and lipid levels, respectively, providing specific insights into disease etiology and health disparities.

  8. The African Past and the Coming of the European. Through African Eyes: Cultures in Change, Unit III.

    ERIC Educational Resources Information Center

    Clark, Leon E., Ed.

    Third in a series of six dealing with African culture and intended for secondary level students, this book deals with the ancient kingdoms of the Western Sudan, the early civilizations of East Africa, the coming of the Europeans, and the Atlantic slave trade. Almost all of the selections in the volume were written by Africans, and they come from a…

  9. Africans Away from Home.

    ERIC Educational Resources Information Center

    Clarke, John Henrik

    Africans who were brought across the Atlantic as slaves never fully adjusted to slavery or accepted its inevitability. Resistance began on board the slave ships, where many jumped overboard or committed suicide. African slaves in South America led the first revolts against tyranny in the New World. The first slave revolt in the Caribbean occurred…

  10. Colonial Roots, Conflict and Peacekeeping in Africa: Defining the Need for an African Airlift Consortium

    DTIC Science & Technology

    2010-05-01

    powers (plus the United States) met in Berlin over a three-month period under the pretext of once and for all stamping out the slave trade on the...recovering from the wounds he received in Nyasaland, Lugard began to “press the needs of the missionaries, and of the tribes ravaged by the slave - trade , for...20 A Adu Boahen, Topics in West African History , Forum series. (London: Longmans, 1966), 134. 21 Shillington, History of Africa, 354.  22

  11. MANIPULATOR FOR SLAVE ROBOT

    DOEpatents

    Goertz, R.C.; Grimson, J.H.; Kohut, F.A.

    1961-04-01

    A remote-control manipulator comprising two stationary master units, two slave units on a movable vehicle, and electrical connections between the master and slave units is reported. The slave units are side by side with a minimum over-all width, which is made feasible by an arrangement of transducers producing most movements of each slave unit to one side of the support of said slave unit.

  12. Early Childhood Education of the African Child in the Diaspora--The Missing Link.

    ERIC Educational Resources Information Center

    Nwosu, Oriaku

    "Africans in the Diaspora" refers to peoples of African origin dispersed throughout South America, the Caribbean, and North America as a result of the Atlantic slave trade carried out by European nations from the seventeenth through nineteenth centuries. The paper first provides an historical overview of the Diaspora. It then discusses…

  13. VEHICLE FOR SLAVE ROBOT

    DOEpatents

    Goertz, R.C.; Lindberg, J.F.

    1962-01-30

    A reeling device is designed for an electrical cable supplying power to the slave slde of a remote control manipulator mounted on a movable vehicle. As the vehicle carries the slave side about in a closed room, the device reels the cable in and out to maintain a variable length of the cable between the vehicle and a cable inlet in the wall of the room. The device also handles a fixed length of cable between the slave side and the vehicle, in spite of angular movement of the slave side with respect to the vehicle. (AEC)

  14. [African population in history].

    PubMed

    Yang, S

    1984-11-29

    The growth rate of the African population has been fluctuating throughout history, affected by political, social, and economic events. 6000 years ago, the majority of the population was based in North Africa, because farming had been developed there. However, between the 11th and the 16th centuries, there was a constant decline in the population of that region, due to invasions from Europe and the black plague. During the same period, the population in the area south of the Sahara grew rapidly, as people there had gone into the iron tool period and farming had been developed. From the 16th to the mid-17th Century, population growth was considerable in Africa; more people had learned the technology of irrigation, corn and potatoes had been introduced from South America, and colonialism was not yet an issue. From the mid-17th to the mid-19th Century, there was no growth, due to the slave trade and wars between tribes. One estimate sets the direct and indirect loss during this period, as a result of the slave trade, at 100 million people. From the 1850s to the end of World War I, population growth started up again, chiefly influenced by the fact that the slave trade had essentially come to a half and modern medical care had become available on the continent. However, in central Africa, the region which suffered the worst blow from the slave trade, growth was very slow, while in East Africa the population was declining because of wars between colonists and natives, as well as natural disasters. Increases in population during this period were a result of immigration from Europe and India. From the end of World War I to the present, growth has been rapid, given improvements in medical services and standards of living, while most of the former colonies became independent after the 1950s. Consequently, almost all African countries are under great pressure now with regard to their populations.

  15. HIV prevalence and risk behaviors among African American Women Who Trade Sex for Drugs Versus Economic Resources.

    PubMed

    Dunne, Eugene M; Dyer, Typhanye Penniman; Khan, Maria R; Cavanaugh, Courtenay E; Melnikov, Alex; Latimer, William W

    2014-07-01

    Trading sex for money, drugs, goods, services, or a place to stay is prevalent among women who use drugs and has been associated with women's risk of HIV acquisition. There is evidence that trading sex for drugs only may be associated with elevated risk of HIV compared with trading sex for money. The purpose of this study was to assess whether HIV risk behaviors and HIV prevalence differ among African American drug using women (N = 92) who traded sex for drugs only, traded sex for economic resources (defined as money, shelter, or other resources) only, or traded sex for both economic resources and drugs. In this study, lower rates of condom use and higher rates of HIV were found among women who traded sex for drugs only compared to women who traded sex for economic resources or for economic resources and drugs. These findings suggest that African American women who trade sex for drugs only represent an understudied yet highly vulnerable group.

  16. Tene Me Quia Fugi (Slave Collar).

    ERIC Educational Resources Information Center

    Strasheim, Lorraine A.

    This mini-text is a series of Martial's epigrams on the slave. The epigrams deal with: slave torture, tenderness to a slave, the slave as a curiosity, flogging, the slave as property, a selling point, the slave as a person, sex and the slave, and slaves as gifts. The epigrams come with complete Latin-English vocabularies and reading notes. The…

  17. Trade in Educational Services: Reflections on the African and South African Higher Education System

    ERIC Educational Resources Information Center

    Sehoole, Chika Trevor

    2004-01-01

    This article discusses and analyses the emergence of globalisation and its impact on developments within the African continent. Africa's response at a regional level through the New Partnership for Africa's Development and at a subregional level through the Southern African Development Community's "Protocol on Education" come under…

  18. Legal ivory trade in a corrupt world and its impact on African elephant populations.

    PubMed

    Bennett, Elizabeth L

    2015-02-01

    Illegal hunting of African elephants (Loxodonta africana) for ivory is causing rapid declines in their populations. Since 2007, illegal ivory trade has more than doubled. African elephants are facing the most serious conservation crisis since 1989, when international trade was banned. One solution proposed is establishment of a controlled legal trade in ivory. High prices for ivory mean that the incentives to obtain large quantities are high, but the quantity of tusks available for trade are biologically constrained. Within that context, effective management of a legal ivory trade would require robust systems to be in place to ensure that ivory from illegally killed elephants cannot be laundered into a legal market. At present, that is not feasible due to corruption among government officials charged with implementing wildlife-related legislation. With organized criminal enterprises involved along the whole commodity chain, corruption enables the laundering of illegal ivory into legal or potentially legal markets. Poachers and traffickers can rapidly pay their way out of trouble, so the financial incentives to break the law heavily outweigh those of abiding by it. Maintaining reliable permitting systems and leak-proof chains of custody in this context is challenging, and effective management breaks down. Once illegal ivory has entered the legal trade, it is difficult or impossible for enforcement officers to know what is legal and illegal. Addressing corruption throughout a trade network that permeates countries across the globe will take decades, if it can ever be achieved. That will be too late for wild African elephants at current rates of loss. If we are to conserve remaining wild populations, we must close all markets because, under current levels of corruption, they cannot be controlled in a way that does not provide opportunities for illegal ivory being laundered into legal markets.

  19. The Trade in African Medicinal Plants in Matonge-Ixelles, Brussels (Belgium).

    PubMed

    van Andel, Tinde; Fundiko, Marie-Cakupewa C

    2016-01-01

    Maintaining cultural identity and preference to treat cultural bound ailments with herbal medicine are motivations for migrants to continue using medicinal plants from their home country after moving to Europe and the USA. As it is generally easier to import exotic food than herbal medicine, migrants often shift to using species that double as food and medicine. This paper focuses on the trade in African medicinal plants in a Congolese neighborhood in Brussels (Belgium). What African medicinal plants are sold in Matonge, where do they come from, and to which extent are they food medicines? Does vendor ethnicity influence the diversity of the herbal medicine sold? We hypothesized that most medicinal plants, traders, and clients in Matonge were of Congolese origin, most plants used medicinally were mainly food crops and that culture-bound illnesses played a prominent role in medicinal plant use. We carried out a market survey in 2014 that involved an inventory of medicinal plants in 19 shops and interviews with 10 clients of African descent, voucher collection and data gathering on vernacular names and uses. We encountered 83 medicinal plant species, of which 71% was primarily used for food. The shredded leaves of Gnetum africanum Welw., Manihot esculenta Crantz, and Ipomoea batatas (L.) Lam were among the most frequently sold vegetables with medicinal uses. Cola nuts, shea butter, Aloe vera (L.) Burm.f., and Mondia whitei (Hook.f.). Skeels were the main non-food medicines sold. Women's health, aphrodisiacs, and rituals were the most important medicinal applications, but culture-bound ailments did not entirely dominate the plant uses. While most clients in Matonge were Congolese, most vendors and plant species were not. The Pakistanis dominated the food trade, and typical Congolese plants were sometimes replaced by West African species, creating confusion in vernacular names. African-managed shops had significantly more species of medicinal plants in stock than shops

  20. Trading or coercion? Variation in male mating strategies between two communities of East African chimpanzees

    PubMed Central

    Kaburu, Stefano S. K.; Newton-Fisher, Nicholas E.

    2015-01-01

    Across taxa, males employ a variety of mating strategies, including sexual coercion and the provision, or trading, of resources. Biological market theory (BMT) predicts that trading of commodities for mating opportunities should exist only when males cannot monopolize access to females and/or obtain mating by force, in situations where power differentials between males are low; both coercion and trading have been reported for chimpanzees (Pan troglodytes). Here, we investigate whether the choice of strategy depends on the variation in male power differentials, using data from two wild communities of East African chimpanzees (Pan troglodytes schweinfurthii): the structurally despotic Sonso community (Budongo, Uganda) and the structurally egalitarian M-group (Mahale, Tanzania). We found evidence of sexual coercion by male Sonso chimpanzees, and of trading—of grooming for mating—by M-group males; females traded sex for neither meat nor protection from male aggression. Our results suggest that the despotism–egalitarian axis influences strategy choice: male chimpanzees appear to pursue sexual coercion when power differentials are large and trading when power differentials are small and coercion consequently ineffective. Our findings demonstrate that trading and coercive strategies are not restricted to particular chimpanzee subspecies; instead, their occurrence is consistent with BMT predictions. Our study raises interesting, and as yet unanswered, questions regarding female chimpanzees’ willingness to trade sex for grooming, if doing so represents a compromise to their fundamentally promiscuous mating strategy. It highlights the importance of within-species cross-group comparisons and the need for further study of the relationship between mating strategy and dominance steepness. PMID:26279605

  1. Slave Narratives: Constructing U.S. History through Analyzing Primary Sources. [Lesson Plan].

    ERIC Educational Resources Information Center

    2002

    The realities of slavery and reconstruction hit home in oral histories from the Library of Congress. In this unit of study, students research slave narratives from the Federal Writers' Project and describe the lives of former African slaves in the United States--both before and after emancipation. From varied sources, students can sample the…

  2. Gender Issues and the Slave Narratives: "Incidents in the Life" and "Narrative of the Life" Compared.

    ERIC Educational Resources Information Center

    DeGout, Yasmin Y.

    The differences between early African American narratives written by women and those written by men can be seen in a comparison of Harriet A. Jacobs's "Incidents in the Life of a Slave Girl, Written by Herself" and Frederick Douglass's "Narrative of the Life of Frederick Douglass, An American Slave." A comparison of these works…

  3. Assigning African elephant DNA to geographic region of origin: Applications to the ivory trade

    PubMed Central

    Wasser, Samuel K.; Shedlock, Andrew M.; Comstock, Kenine; Ostrander, Elaine A.; Mutayoba, Benezeth; Stephens, Matthew

    2004-01-01

    Resurgence of illicit trade in African elephant ivory is placing the elephant at renewed risk. Regulation of this trade could be vastly improved by the ability to verify the geographic origin of tusks. We address this need by developing a combined genetic and statistical method to determine the origin of poached ivory. Our statistical approach exploits a smoothing method to estimate geographic-specific allele frequencies over the entire African elephants' range for 16 microsatellite loci, using 315 tissue and 84 scat samples from forest (Loxodonta africana cyclotis) and savannah (Loxodonta africana africana) elephants at 28 locations. These geographic-specific allele frequency estimates are used to infer the geographic origin of DNA samples, such as could be obtained from tusks of unknown origin. We demonstrate that our method alleviates several problems associated with standard assignment methods in this context, and the absolute accuracy of our method is high. Continent-wide, 50% of samples were located within 500 km, and 80% within 932 km of their actual place of origin. Accuracy varied by region (median accuracies: West Africa, 135 km; Central Savannah, 286 km; Central Forest, 411 km; South, 535 km; and East, 697 km). In some cases, allele frequencies vary considerably over small geographic regions, making much finer discriminations possible and suggesting that resolution could be further improved by collection of samples from locations not represented in our study. PMID:15459317

  4. Assigning African elephant DNA to geographic region of origin: applications to the ivory trade.

    PubMed

    Wasser, Samuel K; Shedlock, Andrew M; Comstock, Kenine; Ostrander, Elaine A; Mutayoba, Benezeth; Stephens, Matthew

    2004-10-12

    Resurgence of illicit trade in African elephant ivory is placing the elephant at renewed risk. Regulation of this trade could be vastly improved by the ability to verify the geographic origin of tusks. We address this need by developing a combined genetic and statistical method to determine the origin of poached ivory. Our statistical approach exploits a smoothing method to estimate geographic-specific allele frequencies over the entire African elephants' range for 16 microsatellite loci, using 315 tissue and 84 scat samples from forest (Loxodonta africana cyclotis) and savannah (Loxodonta africana africana) elephants at 28 locations. These geographic-specific allele frequency estimates are used to infer the geographic origin of DNA samples, such as could be obtained from tusks of unknown origin. We demonstrate that our method alleviates several problems associated with standard assignment methods in this context, and the absolute accuracy of our method is high. Continent-wide, 50% of samples were located within 500 km, and 80% within 932 km of their actual place of origin. Accuracy varied by region (median accuracies: West Africa, 135 km; Central Savannah, 286 km; Central Forest, 411 km; South, 535 km; and East, 697 km). In some cases, allele frequencies vary considerably over small geographic regions, making much finer discriminations possible and suggesting that resolution could be further improved by collection of samples from locations not represented in our study.

  5. Complex master slave interferometry.

    PubMed

    Rivet, Sylvain; Maria, Michael; Bradu, Adrian; Feuchter, Thomas; Leick, Lasse; Podoleanu, Adrian

    2016-02-08

    A general theoretical model is developed to improve the novel Spectral Domain Interferometry method denoted as Master/Slave (MS) Interferometry. In this model, two functions, g and h are introduced to describe the modulation chirp of the channeled spectrum signal due to nonlinearities in the decoding process from wavenumber to time and due to dispersion in the interferometer. The utilization of these two functions brings two major improvements to previous implementations of the MS method. A first improvement consists in reducing the number of channeled spectra necessary to be collected at Master stage. In previous MSI implementation, the number of channeled spectra at the Master stage equated the number of depths where information was selected from at the Slave stage. The paper demonstrates that two experimental channeled spectra only acquired at Master stage suffice to produce A-scans from any number of resolved depths at the Slave stage. A second improvement is the utilization of complex signal processing. Previous MSI implementations discarded the phase. Complex processing of the electrical signal determined by the channeled spectrum allows phase processing that opens several novel avenues. A first consequence of such signal processing is reduction in the random component of the phase without affecting the axial resolution. In previous MSI implementations, phase instabilities were reduced by an average over the wavenumber that led to reduction in the axial resolution.

  6. ELECTRONIC MASTER SLAVE MANIPULATOR

    DOEpatents

    Goertz, R.C.; Thompson, Wm.M.; Olsen, R.A.

    1958-08-01

    A remote control manipulator is described in which the master and slave arms are electrically connected to produce the desired motions. A response signal is provided in the master unit in order that the operator may sense a feel of the object and may not thereby exert such pressures that would ordinarily damage delicate objects. This apparatus will permit the manipulation of objects at a great distance, that may be viewed over a closed TV circuit, thereby permitting a remote operator to carry out operations in an extremely dangerous area with complete safety.

  7. Africans in America.

    ERIC Educational Resources Information Center

    Hart, Ayanna; Spangler, Earl

    This book introduces African-American history and culture to children. The first Africans in America came from many different regions and cultures, but became united in this country by being black, African, and slaves. Once in America, Africans began a long struggle for freedom which still continues. Slavery, the Civil War, emancipation, and the…

  8. Psychological correlates of trading sex for money among African American crack cocaine smokers.

    PubMed

    Risser, Jan M H; Timpson, Sandra C; McCurdy, Sheryl A; Ross, Michael W; Williams, Mark L

    2006-01-01

    This article compares demographic characteristics, sexual practices, and psychosocial status among 193 African American female crack cocaine users who currently, previously, or never traded sex for money. Current traders were less likely to have a main sexual partner, more likely to have a casual sexual partner, and more likely to smoke larger quantities of crack. There was a significant trend towards current traders reporting lower self-esteem, greater depression and anxiety, poorer decision-making confidence, more hostility, less social conformity, greater risk taking behaviors, and more problems growing up, compared to previous and never traders. These differences suggest that interventions should address self-esteem, risk-taking practices, depression and anxiety as well as other psychosocial factors.

  9. Forensic application of DNA barcoding for identification of illegally traded African pangolin scales.

    PubMed

    Mwale, Monica; Dalton, Desire L; Jansen, Raymond; De Bruyn, Marli; Pietersen, Darren; Mokgokong, Prudent S; Kotzé, Antoinette

    2017-03-01

    The escalating growth in illegal wildlife trade and anthropogenic habitat changes threaten the survival of pangolin species worldwide. All eight extant species have experienced drastic population size reductions globally with a high extinction risk in Asia. Consequently, forensic services have become critical for law enforcement, with a need for standardised and validated genetic methods for reliable identifications. The seizure of three tonnes of pangolin scales, believed to have originated from Africa, by Hong Kong Customs Authorities provided an opportunity for the application of DNA barcoding in identifying scales. Three mitochondrial DNA gene regions (COI, Cyt b, and D-loop) were amplified for a subsample of the confiscated material and compared with taxonomically verified references. All four African species were recovered as monophyletic with high interspecific uncorrected p-distance estimates (0.048-0.188) among genes. However, only three of four African species (Phataginus tricuspis, Phataginus tetradactyla, and Smutsia gigantea, originating from West and Central Africa) and one of four Asian species (Manis javanica from Southeast Asia) were identified among scales. Although the assignment of unknown scales to specific species was reliable, additional genetic tools and representative reference material are required to determine geographic origins of confiscated pangolin specimens.

  10. Confronting Thomas Jefferson, Slave Owner.

    ERIC Educational Resources Information Center

    Blackman, James A.

    1992-01-01

    Although Thomas Jefferson's view of freedom was the cornerstone of the Declaration of Independence, this founding father owned 170 slaves to run his 5,000 acre plantation. This article describes a unit developed by the Monticello (Virginia) Education Department that teaches secondary students about slave Isaac Jefferson while exposing them to…

  11. FASTBUS Slaves: a designers view

    SciTech Connect

    Downing, R.W.

    1981-10-01

    Although FASTBUS has features built into it which allow complex interconnections and multiple Masters, the rules for implementing Slaves are very simple. The first time designer of Slave Modules should not be intimidated by the 200 pages of the FASTBUS document. About 90% of the specification is associated with system implications that do not impact Slave design. This paper will review the basic logic and timing requirements for FASTBUS Slave design. Also, some examples of implementation will be shown. The discussion which follows assumes that mastership of the bus has been gained. Bus arbitration, system interconnection, message routing, etc. are separate topics and will not be discussed here. These topics affect only the design of devices which operate at the system level since FASTBUS Slave modules have been specified to be completely transparent to these system considerations.

  12. Risks to Birds Traded for African Traditional Medicine: A Quantitative Assessment

    PubMed Central

    Williams, Vivienne L.; Cunningham, Anthony B.; Kemp, Alan C.; Bruyns, Robin K.

    2014-01-01

    Few regional or continent-wide assessments of bird use for traditional medicine have been attempted anywhere in the world. Africa has the highest known diversity of bird species used for this purpose. This study assesses the vulnerability of 354 bird species used for traditional medicine in 25 African countries, from 205 genera, 70 families, and 25 orders. The orders most represented were Passeriformes (107 species), Falconiformes (45 species), and Coraciiformes (24 species), and the families Accipitridae (37 species), Ardeidae (15 species), and Bucerotidae (12 species). The Barn owl (Tyto alba) was the most widely sold species (seven countries). The similarity of avifaunal orders traded is high (analogous to “morphospecies”, and using Sørensen's index), which suggests opportunities for a common understanding of cultural factors driving demand. The highest similarity was between bird orders sold in markets of Benin vs. Burkina Faso (90%), but even bird orders sold in two geographically separated countries (Benin vs. South Africa and Nigeria vs. South Africa) were 87% and 81% similar, respectively. Rabinowitz's “7 forms of rarity” model, used to group species according to commonness or rarity, indicated that 24% of traded bird species are very common, locally abundant in several habitats, and occur over a large geographical area, but 10% are rare, occur in low numbers in specific habitats, and over a small geographical area. The order with the highest proportion of rare species was the Musophagiformes. An analysis of species mass (as a proxy for size) indicated that large and/or conspicuous species tend to be targeted by harvesters for the traditional medicine trade. Furthermore, based on cluster analyses for species groups of similar risk, vultures, hornbills, and other large avifauna, such as bustards, are most threatened by selective harvesting and should be prioritised for conservation action. PMID:25162700

  13. African Expressions in Hispano-American Literature.

    ERIC Educational Resources Information Center

    Coleman, Ben C.

    This revised version of a lecture on the relationship of African language and Hispano-American literature illustrates the historical influence of the African slave on representative literature and modern culture of the Caribbean Islands. Introductory remarks focus on the migratory patterns of the African slaves. The concept of negritude is then…

  14. Regional trade and the nutrition transition: opportunities to strengthen NCD prevention policy in the Southern African Development Community.

    PubMed

    Thow, Anne Marie; Sanders, David; Drury, Eliza; Puoane, Thandi; Chowdhury, Syeda N; Tsolekile, Lungiswa; Negin, Joel

    2015-01-01

    Background Addressing diet-related non-communicable diseases (NCDs) will require a multisectoral policy approach that includes the food supply and trade, but implementing effective policies has proved challenging. The Southern African Development Community (SADC) has experienced significant trade and economic liberalization over the past decade; at the same time, the nutrition transition has progressed rapidly in the region. This analysis considers the relationship between regional trade liberalization and changes in the food environment associated with poor diets and NCDs, with the aim of identifying feasible and proactive policy responses to support healthy diets. Design Changes in trade and investment policy for the SADC were documented and compared with time-series graphs of import data for soft drinks and snack foods to assess changes in imports and source country in relation to trade and investment liberalization. Our analysis focuses on regional trade flows. Results Diets and the burden of disease in the SADC have changed since the 1990s in parallel with trade and investment liberalization. Imports of soft drinks increased by 76% into SADC countries between 1995 and 2010, and processed snack foods by 83%. South Africa acts as a regional trade and investment hub; it is the major source of imports and investment related to these products into other SADC countries. At the same time, imports of processed foods and soft drinks from outside the region - largely from Asia and the Middle East - are increasing at a dramatic rate with soft drink imports growing by almost 1,200% and processed snack foods by 750%. Conclusions There is significant intra-regional trade in products associated with the nutrition transition; however, growing extra-regional trade means that countries face new pressures in implementing strong policies to prevent the increasing burden of diet-related NCDs. Implementation of a regional nutrition policy framework could complement the SADC

  15. Regional trade and the nutrition transition: opportunities to strengthen NCD prevention policy in the Southern African Development Community

    PubMed Central

    Thow, Anne Marie; Sanders, David; Drury, Eliza; Puoane, Thandi; Chowdhury, Syeda N.; Tsolekile, Lungiswa; Negin, Joel

    2015-01-01

    Background Addressing diet-related non-communicable diseases (NCDs) will require a multisectoral policy approach that includes the food supply and trade, but implementing effective policies has proved challenging. The Southern African Development Community (SADC) has experienced significant trade and economic liberalization over the past decade; at the same time, the nutrition transition has progressed rapidly in the region. This analysis considers the relationship between regional trade liberalization and changes in the food environment associated with poor diets and NCDs, with the aim of identifying feasible and proactive policy responses to support healthy diets. Design Changes in trade and investment policy for the SADC were documented and compared with time-series graphs of import data for soft drinks and snack foods to assess changes in imports and source country in relation to trade and investment liberalization. Our analysis focuses on regional trade flows. Results Diets and the burden of disease in the SADC have changed since the 1990s in parallel with trade and investment liberalization. Imports of soft drinks increased by 76% into SADC countries between 1995 and 2010, and processed snack foods by 83%. South Africa acts as a regional trade and investment hub; it is the major source of imports and investment related to these products into other SADC countries. At the same time, imports of processed foods and soft drinks from outside the region – largely from Asia and the Middle East – are increasing at a dramatic rate with soft drink imports growing by almost 1,200% and processed snack foods by 750%. Conclusions There is significant intra-regional trade in products associated with the nutrition transition; however, growing extra-regional trade means that countries face new pressures in implementing strong policies to prevent the increasing burden of diet-related NCDs. Implementation of a regional nutrition policy framework could complement the SADC

  16. Trade-offs of predation and foraging explain sexual segregation in African buffalo

    USGS Publications Warehouse

    Hay, C.T.; Cross, P.C.; Funston, P.J.

    2008-01-01

    1. Many studies have investigated why males and females segregate spatially in sexually dimorphic species. These studies have focused primarily on temperate zone ungulates in areas lacking intact predator communities, and few have directly assessed predation rates in different social environments. 2. Data on the movement, social affiliation, mortality and foraging of radio-collared African buffalo (Syncerus caffer) were collected from 2001-06 in the Kruger National Park, South Africa. 3. The vast majority of mortality events were due to lion (Panthera leo) predation, and the mortality hazard associated with being an adult male buffalo in a male-only 'bachelor' group was almost four times higher than for adult females in mixed herds. The mortality rates of adult males and females within mixed herds were not statistically different. Mortality sites of male and female buffalo were in areas of low visibility similar to those used by bachelor groups, while mixed herds tended to use more open habitats. 4. Males in bachelor groups ate similar or higher quality food (as indexed by percentage faecal nitrogen), and moved almost a third less distance per day compared with mixed herds. As a result, males in bachelor groups gained more body condition than did males in breeding herds. 5. Recent comparative analyses suggest the activity-budget hypothesis as a common underlying cause of social segregation. However, our intensive study, in an area with an intact predator community showed that male and female buffalo segregated by habitat and supported the predation-risk hypothesis. Male African buffalo appear to trade increased predation risk for additional energy gains in bachelor groups, which presumably leads to increased reproductive success. ?? 2008 The Authors.

  17. Trade-offs of predation and foraging explain sexual segregation in African buffalo.

    PubMed

    Hay, C T; Cross, P C; Funston, P J

    2008-09-01

    1. Many studies have investigated why males and females segregate spatially in sexually dimorphic species. These studies have focused primarily on temperate zone ungulates in areas lacking intact predator communities, and few have directly assessed predation rates in different social environments. 2. Data on the movement, social affiliation, mortality and foraging of radio-collared African buffalo (Syncerus caffer) were collected from 2001-06 in the Kruger National Park, South Africa. 3. The vast majority of mortality events were due to lion (Panthera leo) predation, and the mortality hazard associated with being an adult male buffalo in a male-only 'bachelor' group was almost four times higher than for adult females in mixed herds. The mortality rates of adult males and females within mixed herds were not statistically different. Mortality sites of male and female buffalo were in areas of low visibility similar to those used by bachelor groups, while mixed herds tended to use more open habitats. 4. Males in bachelor groups ate similar or higher quality food (as indexed by percentage faecal nitrogen), and moved almost a third less distance per day compared with mixed herds. As a result, males in bachelor groups gained more body condition than did males in breeding herds. 5. Recent comparative analyses suggest the activity-budget hypothesis as a common underlying cause of social segregation. However, our intensive study, in an area with an intact predator community showed that male and female buffalo segregated by habitat and supported the predation-risk hypothesis. Male African buffalo appear to trade increased predation risk for additional energy gains in bachelor groups, which presumably leads to increased reproductive success.

  18. Improved electromechanical master-slave manipulator

    NASA Technical Reports Server (NTRS)

    Forster, G.; Goertz, R.; Grimson, J.; Mingesz, D.; Potts, C.

    1968-01-01

    Electric master-slave manipulator uses force multiplication and allows the operator to remotely control the slave arm. Both the master and slave arms execute seven distinct motions by a specially designed force-reflecting servo having a one to one correspondence between the motion at the master and slave.

  19. The Slave Narrative: An Image of Excellence.

    ERIC Educational Resources Information Center

    Malden, Cynthia L.

    Through the narratives of North American slaves a vivid picture of their lives, struggles, hopes, and aspirations emerges. The slave narrative arose as a response to, and a refutation of, claims that blacks could not write. Slave writings were often direct extensions of speech. Through a process of imitation and repetition, the black slave's…

  20. Genome-wide patterns of population structure and admixture in West Africans and African Americans.

    PubMed

    Bryc, Katarzyna; Auton, Adam; Nelson, Matthew R; Oksenberg, Jorge R; Hauser, Stephen L; Williams, Scott; Froment, Alain; Bodo, Jean-Marie; Wambebe, Charles; Tishkoff, Sarah A; Bustamante, Carlos D

    2010-01-12

    Quantifying patterns of population structure in Africans and African Americans illuminates the history of human populations and is critical for undertaking medical genomic studies on a global scale. To obtain a fine-scale genome-wide perspective of ancestry, we analyze Affymetrix GeneChip 500K genotype data from African Americans (n = 365) and individuals with ancestry from West Africa (n = 203 from 12 populations) and Europe (n = 400 from 42 countries). We find that population structure within the West African sample reflects primarily language and secondarily geographical distance, echoing the Bantu expansion. Among African Americans, analysis of genomic admixture by a principal component-based approach indicates that the median proportion of European ancestry is 18.5% (25th-75th percentiles: 11.6-27.7%), with very large variation among individuals. In the African-American sample as a whole, few autosomal regions showed exceptionally high or low mean African ancestry, but the X chromosome showed elevated levels of African ancestry, consistent with a sex-biased pattern of gene flow with an excess of European male and African female ancestry. We also find that genomic profiles of individual African Americans afford personalized ancestry reconstructions differentiating ancient vs. recent European and African ancestry. Finally, patterns of genetic similarity among inferred African segments of African-American genomes and genomes of contemporary African populations included in this study suggest African ancestry is most similar to non-Bantu Niger-Kordofanian-speaking populations, consistent with historical documents of the African Diaspora and trans-Atlantic slave trade.

  1. Master-slave micromanipulator method

    DOEpatents

    Morimoto, Alan K.; Kozlowski, David M.; Charles, Steven T.; Spalding, James A.

    1999-01-01

    A method based on precision X-Y stages that are stacked. Attached to arms projecting from each X-Y stage are a set of two axis gimbals. Attached to the gimbals is a rod, which provides motion along the axis of the rod and rotation around its axis. A dual-planar apparatus that provides six degrees of freedom of motion precise to within microns of motion. Precision linear stages along with precision linear motors, encoders, and controls provide a robotics system. The motors can be remotized by incorporating a set of bellows on the motors and can be connected through a computer controller that will allow one to be a master and the other one to be a slave. Position information from the master can be used to control the slave. Forces of interaction of the slave with its environment can be reflected back to the motor control of the master to provide a sense of force sensed by the slave. Forces import onto the master by the operator can be fed back into the control of the slave to reduce the forces required to move it.

  2. Master-slave micromanipulator apparatus

    DOEpatents

    Morimoto, Alan K.; Kozlowski, David M.; Charles, Steven T.; Spalding, James A.

    1999-01-01

    An apparatus based on precision X-Y stages that are stacked. Attached to arms projecting from each X-Y stage are a set of two axis gimbals. Attached to the gimbals is a rod, which provides motion along the axis of the rod and rotation around its axis. A dual-planar apparatus that provides six degrees of freedom of motion precise to within microns of motion. Precision linear stages along with precision linear motors, encoders, and controls provide a robotics system. The motors can be positioned in a remote location by incorporating a set of bellows on the motors and can be connected through a computer controller that will allow one to be a master and the other one to be a slave. Position information from the master can be used to control the slave. Forces of interaction of the slave with its environment can be reflected back to the motor control of the master to provide a sense of force sensed by the slave. Forces import onto the master by the operator can be fed back into the control of the slave to reduce the forces required to move it.

  3. Master-slave micromanipulator apparatus

    DOEpatents

    Morimoto, A.K.; Kozlowski, D.M.; Charles, S.T.; Spalding, J.A.

    1999-08-31

    An apparatus is disclosed based on precision X-Y stages that are stacked. Attached to arms projecting from each X-Y stage are a set of two axis gimbals. Attached to the gimbals is a rod, which provides motion along the axis of the rod and rotation around its axis. A dual-planar apparatus that provides six degrees of freedom of motion precise to within microns of motion. Precision linear stages along with precision linear motors, encoders, and controls provide a robotics system. The motors can be positioned in a remote location by incorporating a set of bellows on the motors and can be connected through a computer controller that will allow one to be a master and the other one to be a slave. Position information from the master can be used to control the slave. Forces of interaction of the slave with its environment can be reflected back to the motor control of the master to provide a sense of force sensed by the slave. Forces import onto the master by the operator can be fed back into the control of the slave to reduce the forces required to move it. 12 figs.

  4. The electrical structure of the Slave craton

    NASA Astrophysics Data System (ADS)

    Jones, Alan G.; Lezaeta, Pamela; Ferguson, Ian J.; Chave, Alan D.; Evans, Rob L.; Garcia, Xavier; Spratt, Jessica

    2003-12-01

    Proceeding, J.B. Dawson Volume, 1, 307-313] on the basis of garnet geochemistry (G10 vs. G9) populations. Deep-probing MT data from the lake bottom instruments infer that the conductor has a total depth-integrated conductivity (conductance) of the order of 2000 Siemens, which, given an internal resistivity of 10-15 Ω m, implies a thickness of 20-30 km. Below the CSMC the electrical resistivity of the lithosphere increases by a factor of 3-5 to values of around 50 Ω m. This change occurs at depths consistent with the graphite-diamond transition, which is taken as consistent with a carbon interpretation for the CSMC. Preliminary three-dimensional MT modelling supports the NE-SW striking geometry for the conductor, and also suggests a NW dip. This geometry is taken as implying that the tectonic processes that emplaced this geophysical-geochemical body are likely related to the subduction of a craton of unknown provenance from the SE (present-day coordinates) during 2630-2620 Ma. It suggests that the lithospheric stacking model of Helmstaedt and Schulze [Helmstaedt, H.H., Schulze, D.J., 1989. Southern African kimberlites and their mantle sample: implications for Archean tectonics and lithosphere evolution. In Ross, J. (Ed.), Kimberlites and Related Rocks, Vol. 1: Their Composition, Occurrence, Origin, and Emplacement. Geological Society of Australia Special Publication, vol. 14, 358-368] is likely correct for the formation of the Slave's current SCLM.

  5. The role of conflict minerals, artisanal mining, and informal trading networks in African intrastate and regional conflicts

    USGS Publications Warehouse

    Chirico, Peter G.; Malpeli, Katherine C.

    2014-01-01

    The relationship between natural resources and armed conflict gained public and political attention in the 1990s, when it became evident that the mining and trading of diamonds were connected with brutal rebellions in several African nations. Easily extracted resources such as alluvial diamonds and gold have been and continue to be exploited by rebel groups to fund their activities. Artisanal and small-scale miners operating under a quasi-legal status often mine these mineral deposits. While many African countries have legalized artisanal mining and established flow chains through which production is intended to travel, informal trading networks frequently emerge in which miners seek to evade taxes and fees by selling to unauthorized buyers. These networks have the potential to become international in scope, with actors operating in multiple countries. The lack of government control over the artisanal mining sector and the prominence of informal trade networks can have severe social, political, and economic consequences. In the past, mineral extraction fuelled violent civil wars in Sierra Leone, Liberia, and Angola, and it continues to do so today in several other countries. The significant influence of the informal network that surrounds artisanal mining is therefore an important security concern that can extend across borders and have far-reaching impacts.

  6. Radiocarbon dating of seized ivory confirms rapid decline in African elephant populations and provides insight into illegal trade.

    PubMed

    Cerling, Thure E; Barnette, Janet E; Chesson, Lesley A; Douglas-Hamilton, Iain; Gobush, Kathleen S; Uno, Kevin T; Wasser, Samuel K; Xu, Xiaomei

    2016-11-22

    Carbon-14 measurements on 231 elephant ivory specimens from 14 large ivory seizures (≥0.5 ton) made between 2002 and 2014 show that most ivory (ca 90%) was derived from animals that had died less than 3 y before ivory was confiscated. This indicates that the assumption of recent elephant death for mortality estimates of African elephants is correct: Very little "old" ivory is included in large ivory shipments from Africa. We found only one specimen of the 231 analyzed to have a lag time longer than 6 y. Patterns of trade differ by regions: East African ivory, based on genetic assignments of geographic origin, has a much higher fraction of "rapid" transit than ivory originating in the Tridom region of Cameroon-Gabon-Congo. Carbon-14 is an important tool in understanding patterns of movement of illegal wildlife products.

  7. Radiocarbon dating of seized ivory confirms rapid decline in African elephant populations and provides insight into illegal trade

    NASA Astrophysics Data System (ADS)

    Cerling, Thure E.; Barnette, Janet E.; Chesson, Lesley A.; Douglas-Hamilton, Iain; Gobush, Kathleen S.; Uno, Kevin T.; Wasser, Samuel K.; Xu, Xiaomei

    2016-11-01

    Carbon-14 measurements on 231 elephant ivory specimens from 14 large ivory seizures (≥0.5 ton) made between 2002 and 2014 show that most ivory (ca. 90%) was derived from animals that had died less than 3 y before ivory was confiscated. This indicates that the assumption of recent elephant death for mortality estimates of African elephants is correct: Very little “old” ivory is included in large ivory shipments from Africa. We found only one specimen of the 231 analyzed to have a lag time longer than 6 y. Patterns of trade differ by regions: East African ivory, based on genetic assignments of geographic origin, has a much higher fraction of “rapid” transit than ivory originating in the Tridom region of Cameroon-Gabon-Congo. Carbon-14 is an important tool in understanding patterns of movement of illegal wildlife products.

  8. Radiocarbon dating of seized ivory confirms rapid decline in African elephant populations and provides insight into illegal trade

    PubMed Central

    Cerling, Thure E.; Barnette, Janet E.; Chesson, Lesley A.; Douglas-Hamilton, Iain; Gobush, Kathleen S.; Wasser, Samuel K.; Xu, Xiaomei

    2016-01-01

    Carbon-14 measurements on 231 elephant ivory specimens from 14 large ivory seizures (≥0.5 ton) made between 2002 and 2014 show that most ivory (ca. 90%) was derived from animals that had died less than 3 y before ivory was confiscated. This indicates that the assumption of recent elephant death for mortality estimates of African elephants is correct: Very little “old” ivory is included in large ivory shipments from Africa. We found only one specimen of the 231 analyzed to have a lag time longer than 6 y. Patterns of trade differ by regions: East African ivory, based on genetic assignments of geographic origin, has a much higher fraction of “rapid” transit than ivory originating in the Tridom region of Cameroon–Gabon–Congo. Carbon-14 is an important tool in understanding patterns of movement of illegal wildlife products. PMID:27821744

  9. Master/slave manipulator system

    NASA Technical Reports Server (NTRS)

    Vykukal, H. C.; King, R. F.; Vallotton, W. C.

    1973-01-01

    System capabilities are equivalent to mobility, dexterity, and strength of human arm. Arrangement of torque motor, harmonic drive, and potentiometer combination allows all power and control leads to pass through center of slave with position-transducer arrangement of master, and "stovepipe joint" is incorporated for manipulator applications.

  10. Exchange circuits for FASTBUS slaves

    SciTech Connect

    Bratskii, A.A.; Matseev, M.Y.; Rybakov, V.G.

    1985-09-01

    This paper describes general-purpose circuits for FASTBUS interfacing of the functional part of a slave device. The circuits contain buffered receivers and transmitters, addressrecognition and data-transfer logic, and the required control/status registers. The described circuits are implemented with series-K500 integrated circuits.

  11. Mapping the Elephants of the 19th Century East African Ivory Trade with a Multi-Isotope Approach

    PubMed Central

    Lee-Thorp, Julia; Collins, Matthew J.; Lane, Paul J.

    2016-01-01

    East African elephants have been hunted for their ivory for millennia but the nineteenth century witnessed strongly escalating demand from Europe and North America. It has been suggested that one consequence was that by the 1880s elephant herds along the coast had become scarce, and to meet demand, trade caravans trekked farther into interior regions of East Africa, extending the extraction frontier. The steady decimation of elephant populations coupled with the extension of trade networks have also been claimed to have triggered significant ecological and socio-economic changes that left lasting legacies across the region. To explore the feasibility of using an isotopic approach to uncover a ‘moving frontier’ of elephant extraction, we constructed a baseline isotope data set (δ13C, δ15N, δ18O and 87Sr/86Sr) for historic East African elephants known to have come from three distinct regions (coastal, Rift Valley, and inland Lakes). Using the isotope results with other climate data and geographical mapping tools, it was possible to characterise elephants from different habitats across the region. This baseline data set was then used to provenance elephant ivory of unknown geographical provenance that was exported from East Africa during the late nineteenth and early twentieth centuries to determine its likely origin. This produced a better understanding of historic elephant geography in the region, and the data have the potential to be used to provenance older archaeological ivories, and to inform contemporary elephant conservation strategies. PMID:27760152

  12. Relationship between African dust carried in the Atlantic trade winds and surges in pediatric asthma attendances in the Caribbean.

    PubMed

    Prospero, Joseph M; Blades, Edmund; Naidu, Raana; Mathison, George; Thani, Haresh; Lavoie, Marc C

    2008-11-01

    Asthma is epidemic in developed and developing countries including those in the Caribbean where it is widely believed that African dust, transported in high concentrations in the Trade Winds every year, is a major causative factor. The link between asthma and dust in the Caribbean is based largely on anecdotal evidence that associates sharp increases in the occurrence of asthma symptoms with hazy conditions often caused by dust. Here we report on a 2-year study of the relationship between the daily concentrations of dust measured in on-shore Trade Winds at Barbados and pediatric asthma attendance rates at Queen Elizabeth Hospital (QEH). We looked for large increases in QEH daily attendances in relation to daily dust concentrations as previously suggested by anecdotal observations. We could not find any obvious relationship although there may be more subtle linkages between dust and asthma. Our measurements show, however, that the concentration of dust in the size range under 2.5 microm diameter is sufficiently high as to challenge United States Environmental Protection Agency air quality standards for respirable particles. Thus, African dust may constitute a health threat of a different nature, producing symptoms less obvious than those of asthma.

  13. Mapping the Elephants of the 19th Century East African Ivory Trade with a Multi-Isotope Approach.

    PubMed

    Coutu, Ashley N; Lee-Thorp, Julia; Collins, Matthew J; Lane, Paul J

    2016-01-01

    East African elephants have been hunted for their ivory for millennia but the nineteenth century witnessed strongly escalating demand from Europe and North America. It has been suggested that one consequence was that by the 1880s elephant herds along the coast had become scarce, and to meet demand, trade caravans trekked farther into interior regions of East Africa, extending the extraction frontier. The steady decimation of elephant populations coupled with the extension of trade networks have also been claimed to have triggered significant ecological and socio-economic changes that left lasting legacies across the region. To explore the feasibility of using an isotopic approach to uncover a 'moving frontier' of elephant extraction, we constructed a baseline isotope data set (δ13C, δ15N, δ18O and 87Sr/86Sr) for historic East African elephants known to have come from three distinct regions (coastal, Rift Valley, and inland Lakes). Using the isotope results with other climate data and geographical mapping tools, it was possible to characterise elephants from different habitats across the region. This baseline data set was then used to provenance elephant ivory of unknown geographical provenance that was exported from East Africa during the late nineteenth and early twentieth centuries to determine its likely origin. This produced a better understanding of historic elephant geography in the region, and the data have the potential to be used to provenance older archaeological ivories, and to inform contemporary elephant conservation strategies.

  14. Relationship between African dust carried in the Atlantic trade winds and surges in pediatric asthma attendances in the Caribbean

    NASA Astrophysics Data System (ADS)

    Prospero, Joseph M.; Blades, Edmund; Naidu, Raana; Mathison, George; Thani, Haresh; Lavoie, Marc C.

    2008-11-01

    Asthma is epidemic in developed and developing countries including those in the Caribbean where it is widely believed that African dust, transported in high concentrations in the Trade Winds every year, is a major causative factor. The link between asthma and dust in the Caribbean is based largely on anecdotal evidence that associates sharp increases in the occurrence of asthma symptoms with hazy conditions often caused by dust. Here we report on a 2-year study of the relationship between the daily concentrations of dust measured in on-shore Trade Winds at Barbados and pediatric asthma attendance rates at Queen Elizabeth Hospital (QEH). We looked for large increases in QEH daily attendances in relation to daily dust concentrations as previously suggested by anecdotal observations. We could not find any obvious relationship although there may be more subtle linkages between dust and asthma. Our measurements show, however, that the concentration of dust in the size range under 2.5 μm diameter is sufficiently high as to challenge United States Environmental Protection Agency air quality standards for respirable particles. Thus, African dust may constitute a health threat of a different nature, producing symptoms less obvious than those of asthma.

  15. Water resources transfers through southern African food trade: water efficiency and climate signals

    NASA Astrophysics Data System (ADS)

    Dalin, Carole; Conway, Declan

    2016-01-01

    Temporal and spatial variability of precipitation in southern Africa is particularly high. The associated drought and flood risks, combined with a largely rain-fed agriculture, pose a challenge for water and food security in the region. As regional collaboration strengthens through the Southern Africa Development Community and trade with other regions increases, it is thus important to understand both how climate variability affects agricultural productivity and how food trade (regional and extra-regional) can contribute to the region's capacity to deal with climate-related shocks. We combine global hydrological model simulations with international food trade data to quantify the water resources embedded in international food trade in southern Africa and with the rest of the world, from 1986-2011. We analyze the impacts of socio-economic changes and climatic variability on agricultural trade and embedded water resources during this period. We find that regional food trade is efficient in terms of water use but may be unsustainable because water-productive exporters, like South Africa, rely on increasingly stressed water resources. The role of imports from the rest of the world in the region's food supply is important, in particular during severe droughts. This reflects how trade can efficiently redistribute water resources across continents in response to a sudden gap in food production. In a context of regional and global integration, our results highlight opportunities for improved water-efficiency and sustainability of the region's food supply via trade.

  16. Water resources transfers through southern African food trade: water efficiency and climate signals

    NASA Astrophysics Data System (ADS)

    Dalin, C.; Conway, D.

    2015-12-01

    Temporal and spatial variability of precipitation in Southern Africa is particularly high. The associated drought and flood risks, combined with a largely rainfed agriculture, pose a challenge for water and food security in this region. It is thus important to understand both how climate variability affects agricultural productivity and how intra- and extra-regional trade can contribute to the region's capacity to deal with climate-related shocks. We combine international food trade data and a global hydrological model to quantify the water resources embedded in international food trade in southern Africa and with the rest of the world, from 1986-2011. We analyze the impacts of socio-economic, political and climatic changes on agricultural trade and embedded water resources during that period. We find that regional food trade is efficient in terms of water resources but may be unsustainable because water-productive exporters, like South Africa, rely on increasingly scarce water resources. The role of imports from the rest of the world in the region's food supply is important, in particular during severe droughts. This reflects how trade can efficiently redistribute water resources across continents in response to a sudden gap in food production and water productivity. As regional collaboration strengthens through the Southern Africa Development Community (SADC) and trade with other regions increases, our results point out opportunities for improved water-efficiency and sustainability of the region's food production via trade.

  17. The slavery hypothesis for hypertension among African Americans: the historical evidence.

    PubMed

    Curtin, P D

    1992-12-01

    The slavery hypothesis for hypertension has stated that the high blood pressures sometimes measured in African Americans are caused by one or more of these conditions: first, salt deficiency in the parts of Africa that supplied slaves for the Americas; second, the trauma of the slave trade itself; third, conditions of slavery in the United States. A review of the historical evidence shows that there was no salt deficiency in those parts of Africa, nor do present-day West Africans have a high incidence of hypertension. Historical evidence does not support the hypothesis that deaths aboard slave ships were caused mainly by conditions that might be conductive to hypertension, such as salt-depleting diseases. Finally, the hypothesis has depended heavily on evidence from the West Indies, which is not relevant for the United States. There is no evidence that diet or the resulting patterns of disease and demography among slaves in the American South were significantly different from those of other poor southerners.

  18. The slavery hypothesis for hypertension among African Americans: the historical evidence.

    PubMed Central

    Curtin, P D

    1992-01-01

    The slavery hypothesis for hypertension has stated that the high blood pressures sometimes measured in African Americans are caused by one or more of these conditions: first, salt deficiency in the parts of Africa that supplied slaves for the Americas; second, the trauma of the slave trade itself; third, conditions of slavery in the United States. A review of the historical evidence shows that there was no salt deficiency in those parts of Africa, nor do present-day West Africans have a high incidence of hypertension. Historical evidence does not support the hypothesis that deaths aboard slave ships were caused mainly by conditions that might be conductive to hypertension, such as salt-depleting diseases. Finally, the hypothesis has depended heavily on evidence from the West Indies, which is not relevant for the United States. There is no evidence that diet or the resulting patterns of disease and demography among slaves in the American South were significantly different from those of other poor southerners. Images p1682-a p1684-a PMID:1456349

  19. "A dictate of both interest and mercy"? Slave hospitals in the antebellum South.

    PubMed

    Kenny, Stephen C

    2010-01-01

    As a contribution to debates on slave health and welfare, this article investigates the variety, functions, and overall significance of infirmaries for the enslaved in the antebellum South. Newspapers, case histories, and surviving institutional records of antebellum Southern infirmaries providing medical treatment for slaves offer a unique opportunity to examine the development of modern American medicine within the "peculiar institution," and to explore a complex site of interactions between the enslaved, physicians, and slave owners. The world of the medical college hospital in South Carolina and an experimenting clinic in Alabama are reconstructed using newspapers and medical case histories. The Patient Register of the Hotel Dieu (1859-64) and the Admission Book of Touro Infirmary (1855-60) are used to highlight the types of enslaved patients sent to these two New Orleans commercial hospitals and to explore connections between the practice of medicine and the business of slave trading in the city. In addition to providing physicians with a steady income, slave infirmaries were key players in the domestic slave trade, as well as mechanisms for professionalization and the mobilization of medical ideas in the American South.

  20. Water resources transfers through southern African food trade: resource efficiency and climate adaptation

    NASA Astrophysics Data System (ADS)

    Dalin, Carole; Conway, Declan

    2015-04-01

    The connections between climate and the water-food nexus are strong and economically significant in southern Africa, yet the role of observed climate variability as a driver of production fluctuations is poorly understood. In addition, as regional collaboration strengthens through the SADC (Southern Africa Development Community) and trade with other regions increases, it is important to understand both how climate variability affects productivity and how intra- and extra-regional trade can contribute to the region's capacity to deal with climate-related productivity shocks. We use international food trade data (FAOSTAT) and a global hydrological model (H08) to quantify the water resources embedded in international food trade across southern Africa and with the rest of the world, from 1986-2011. We analyze the impacts of socio-economic, political and climatic changes on agricultural trade and embedded water resources during that period. In particular, the effects of climate variability on trade flows and crop yields are estimated, to provide insights on the potential of trade as a collaborative adaptation mechanism.

  1. Population affinities of African Colombians to Sub-Saharan Africans based on dental morphology.

    PubMed

    Delgado-Burbano, M E

    2007-01-01

    The Atlantic slave trade moved more than 13 million Africans to American lands between the 15th and 19th centuries. Previous historical, linguistic, and social-cultural studies suggested a Western-Central Bantu African origin for the Colombian slaves; however, their precise provenance remains unclear. The present study investigates the variation of the epigenetic dental traits in the deciduous and permanent dentition and phenotypic affinities of a contemporary Afro-Colombian community (n=178) in an attempt to identify their possible African ancestors. The results of a multivariate analysis of principal components show that Afro-descendents from Guapi have strong phenotypic relationships with several Bantu-speakers groups of Western and Western-Central Africa (Sub-Saharan region), specifically from Gabon, Congo, Pygmies, Nigeria, Cameroon, Togo and Benin. In concordance with recent mtDNA studies, this research suggests a distant but important relationship between Afro-Colombians and Eastern and South-Eastern African populations. This analysis also shows a marked dental divergence with North African samples. The dental information is not very different from the cultural, linguistic and historic data; however, it is more in agreement with studies based on molecular variation. In addition, this study reveals that African-Americans from North America, Central America-Caribbean and South America have high biological variation essentially identical to their several Sub-Saharan sources. Although a microevolutionary model, based on differential rates of gene flow with Native American and European-American groups and little selective pressures influence, better explains the phenotypic variation observed, more African-American dental samples must be analyzed from a regional perspective.

  2. Correlates of the sex trade among African-American youth living in urban public housing: assessing the role of parental incarceration and parental substance use.

    PubMed

    Nebbitt, Von; Tirmazi, Taqi M; Lombe, Margaret; Cryer-Coupet, Qiana; French, Shelby

    2014-04-01

    African-American youth are disproportionately affected by parental incarceration and the consequences of parental substance use. Many adapt to the loss of their parents to prison or drug addiction by engaging in sex-risk behavior, particularly the sex trade. These youth may engage in this risky behavior for a number of reasons. Although previous research has examined this issue, most of these studies have focused on runaway or street youth or youth in international settings. Empirical evidence on correlates of trading sex for money among urban African-American youth is practically missing. Using a sample of 192 African-American youth living in urban public housing, this paper attempts to rectify this gap in knowledge by assessing how individual and parental factors are related to the likelihood of a youth trading sex for money. The sample for this study reported a mean age of 19; 28 % reported having traded sex for money; 30 % had a father currently in prison; and 7 % reported having a mother currently in prison. Maternal incarceration and paternal substance use were associated with a higher likelihood of trading sex for money. Given the potential health risks associated with trading sex for money, understanding correlates of this behavior has important implications for the health of this vulnerable population of youth and urban health in general.

  3. 77 FR 21995 - Trade Facilitation in the East African Community: Recent Developments and Potential Benefits...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-12

    ..., Institution of Investigation and Request for Written Statements AGENCY: United States International Trade Commission. ACTION: Institution of investigation and request for written statements. SUMMARY: Following... Developments and Potential Benefits. DATES: May 10, 2012: Deadline for filing written submissions. July 2,...

  4. African Trade Unions and the Challenge of Organizing Women Workers in the Unorganized Sectors.

    ERIC Educational Resources Information Center

    Date-Bah, Eugenia

    1993-01-01

    Democratization should be considered in terms of equal representation of women and men in government as well as in the relevant bodies and decision-making organs of society. Trade unions should be perceived and assessed in relation to the participation of women within their structures and the reflection of women's concerns in their policies and…

  5. Long‐term spatio‐temporal changes in a West African bushmeat trade system

    PubMed Central

    McNamara, J.; Kusimi, J. M.; Rowcliffe, J. M.; Cowlishaw, G.; Brenyah, A.; Milner‐Gulland, E. J.

    2015-01-01

    Abstract Landscapes in many developing countries consist of a heterogeneous matrix of mixed agriculture and forest. Many of the generalist species in this matrix are increasingly traded in the bushmeat markets of West and Central Africa. However, to date there has been little quantification of how the spatial configuration of the landscape influences the urban bushmeat trade over time. As anthropogenic landscapes become the face of rural West Africa, understanding the dynamics of these systems has important implications for conservation and landscape management. The bushmeat production of an area is likely to be defined by landscape characteristics such as habitat disturbance, hunting pressure, level of protection, and distance to market. We explored (SSG, tense) the role of these four characteristics in the spatio‐temporal dynamics of the commercial bushmeat trade around the city of Kumasi, Ghana, over 27 years (1978 to 2004). We used geographic information system methods to generate maps delineating the spatial characteristics of the landscapes. These data were combined with spatially explicit market data collected in the main fresh bushmeat market in Kumasi to explore the relationship between trade volume (measured in terms of number of carcasses) and landscape characteristics. Over time, rodents, specifically cane rats (Thryonomys swinderianus), became more abundant in the trade relative to ungulates and the catchment area of the bushmeat market expanded. Areas of intermediate disturbance supplied more bushmeat, but protected areas had no effect. Heavily hunted areas showed significant declines in bushmeat supply over time. Our results highlight the role that low intensity, heterogeneous agricultural landscapes can play in providing ecosystem services, such as bushmeat, and therefore the importance of incorporating bushmeat into ecosystem service mapping exercises. Our results also indicate that even where high bushmeat production is possible, current harvest

  6. Long-term spatio-temporal changes in a West African bushmeat trade system.

    PubMed

    McNamara, J; Kusimi, J M; Rowcliffe, J M; Cowlishaw, G; Brenyah, A; Milner-Gulland, E J

    2015-10-01

    Landscapes in many developing countries consist of a heterogeneous matrix of mixed agriculture and forest. Many of the generalist species in this matrix are increasingly traded in the bushmeat markets of West and Central Africa. However, to date there has been little quantification of how the spatial configuration of the landscape influences the urban bushmeat trade over time. As anthropogenic landscapes become the face of rural West Africa, understanding the dynamics of these systems has important implications for conservation and landscape management. The bushmeat production of an area is likely to be defined by landscape characteristics such as habitat disturbance, hunting pressure, level of protection, and distance to market. We explored (SSG, tense) the role of these four characteristics in the spatio-temporal dynamics of the commercial bushmeat trade around the city of Kumasi, Ghana, over 27 years (1978 to 2004). We used geographic information system methods to generate maps delineating the spatial characteristics of the landscapes. These data were combined with spatially explicit market data collected in the main fresh bushmeat market in Kumasi to explore the relationship between trade volume (measured in terms of number of carcasses) and landscape characteristics. Over time, rodents, specifically cane rats (Thryonomys swinderianus), became more abundant in the trade relative to ungulates and the catchment area of the bushmeat market expanded. Areas of intermediate disturbance supplied more bushmeat, but protected areas had no effect. Heavily hunted areas showed significant declines in bushmeat supply over time. Our results highlight the role that low intensity, heterogeneous agricultural landscapes can play in providing ecosystem services, such as bushmeat, and therefore the importance of incorporating bushmeat into ecosystem service mapping exercises. Our results also indicate that even where high bushmeat production is possible, current harvest levels may

  7. Combating the illegal trade in African elephant ivory with DNA forensics.

    PubMed

    Wasser, Samuel K; Joseph Clark, William; Drori, Ofir; Stephen Kisamo, Emily; Mailand, Celia; Mutayoba, Benezeth; Stephens, Matthew

    2008-08-01

    International wildlife crime is burgeoning in this climate of global trade. We contend that the most effective way to contain this illegal trade is to determine where the wildlife is being removed. This allows authorities to direct law enforcement to poaching hot spots, potentially stops trade before the wildlife is actually killed, prevents countries from denying their poaching problems at home, and thwarts trade before it enters into an increasingly complex web of international criminal activity. Forensic tools have been limited in their ability to determine product origin because the information they can provide typically begins only at the point of shipment. DNA assignment analyses can determine product origin, but its use has been limited by the inability to assign samples to locations where reference samples do not exist. We applied new DNA assignment methods that can determine the geographic origin(s) of wildlife products from anywhere within its range. We used these methods to examine the geographic origin(s) of 2 strings of seizures involving large volumes of elephant ivory, 1 string seized in Singapore and Malawi and the other in Hong Kong and Cameroon. These ivory traffickers may comprise 2 of the largest poaching rings in Africa. In both cases all ivory seized in the string had common origins, which indicates that crime syndicates are targeting specific populations for intense exploitation. This result contradicts the dominant belief that dealers are using a decentralized plan of procuring ivory stocks as they became available across Africa. Large quantities of ivory were then moved, in multiple shipments, through an intermediate country prior to shipment to Asia, as a risk-reduction strategy that distances the dealer from the poaching locale. These smuggling strategies could not have been detected by forensic information, which typically begins only at the shipping source.

  8. Bight of Benin: a Maternal Perspective of Four Beninese Populations and their Genetic Implications on the American Populations of African Ancestry.

    PubMed

    Primativo, Giuseppina; Ottoni, Claudio; Biondi, Gianfranco; Serafino, Sara; Martínez-Labarga, Cristina; Larmuseau, Maarten H D; Scardi, Michele; Decorte, Ronny; Rickards, Olga

    2017-03-01

    The understanding of the first movements of the ancestral populations within the African continent is still unclear, particularly in West Africa, due to several factors that have shaped the African genetic pool across time. To improve the genetic representativeness of the Beninese population and to better understand the patterns of human settlement inside West Africa and the dynamics of peopling of the Democratic Republic of Benin, we analyzed the maternal genetic variation of 193 Beninese individuals belonging to Bariba, Berba, Dendi, and Fon populations. Results support the oral traditions indicating that the western neighbouring populations have been the ancestors of the first Beninese populations, and the extant genetic structure of the Beninese populations is most likely the result of admixture between populations from neighbouring countries and native people. The present findings highlight how the Beninese populations contributed to the gene pool of the extant populations of some American populations of African ancestry. This strengthens the hypothesis that the Bight of Benin was not only an assembly point for the slave trade during the Trans-Atlantic Slave Trade but also an important slave trapping area.

  9. A Generalized Slave-Particle Method

    NASA Astrophysics Data System (ADS)

    Georgescu, Alexandru Bogdan; Ismail-Beigi, Sohrab

    2015-03-01

    Two slave-particle methods, namely the slave-rotor and the slave-spin approaches, have been of recent interest in the computational correlated electron community. Both methods solve Hubbard-type models and go beyond the single-particle approximations by describing aspects of correlated electron behavior in a computationally efficient manner. We present a generalized slave-particle formalism that connects the the two while reproducing the results of each method in the appropriate limit. The framework automatically corrects the problematic small U behavior of the slave-rotor approach while reproducing its behavior in situations where it has been found physically relevant (e.g., for nickelate heterostructures). This work is supported by the National Science Foundation through Grant MRSEC NSF DMR-1119826.

  10. Y Chromosome Lineages in Men of West African Descent

    PubMed Central

    Keita, Shomarka O. Y.; Kittles, Rick A.

    2012-01-01

    The early African experience in the Americas is marked by the transatlantic slave trade from ∼1619 to 1850 and the rise of the plantation system. The origins of enslaved Africans were largely dependent on European preferences as well as the availability of potential laborers within Africa. Rice production was a key industry of many colonial South Carolina low country plantations. Accordingly, rice plantations owners within South Carolina often requested enslaved Africans from the so-called “Grain Coast” of western Africa (Senegal to Sierra Leone). Studies on the African origins of the enslaved within other regions of the Americas have been limited. To address the issue of origins of people of African descent within the Americas and understand more about the genetic heterogeneity present within Africa and the African Diaspora, we typed Y chromosome specific markers in 1,319 men consisting of 508 west and central Africans (from 12 populations), 188 Caribbeans (from 2 islands), 532 African Americans (AAs from Washington, DC and Columbia, SC), and 91 European Americans. Principal component and admixture analyses provide support for significant Grain Coast ancestry among African American men in South Carolina. AA men from DC and the Caribbean showed a closer affinity to populations from the Bight of Biafra. Furthermore, 30–40% of the paternal lineages in African descent populations in the Americas are of European ancestry. Diverse west African ancestries and sex-biased gene flow from EAs has contributed greatly to the genetic heterogeneity of African populations throughout the Americas and has significant implications for gene mapping efforts in these populations. PMID:22295064

  11. Sexual victimization and family violence among urban African American adolescent women: do violence cluster profiles predict partner violence victimization and sex trade exposure?

    PubMed

    Kennedy, Angie C; Bybee, Deborah; Kulkarni, Shanti J; Archer, Gretchen

    2012-11-01

    Guided by an intersectional feminist perspective, we examined sexual victimization, witnessing intimate partner violence (IPV) in the family, and familial physical abuse among a sample of 180 urban African American adolescent women. We used cluster analysis to better understand the profiles of cumulative victimization, and the relationships between profiles and IPV victimization and personal exposure to the sex trade. Just under one third of the sample reported sexual victimization, with cooccurrence with both forms of family violence common. The cluster profile with high levels of severe family violence was associated with the highest rate of IPV victimization and sex trade exposure.

  12. Molecular evidence supports an african affinity of the neotropical freshwater gastropod, Biomphalaria glabrata, say 1818, an intermediate host for Schistosoma mansoni.

    PubMed Central

    Campbell, G; Jones, C S; Lockyer, A E; Hughes, S; Brown, D; Noble, L R; Rollinson, D

    2000-01-01

    Freshwater snails of the genus Biomphalaria, Preston 1910, are the most important and widely distributed intermediate hosts of Schistosoma mansoni, the blood fluke responsible for human intestinal schistosomiasis, in Africa and the Neotropics. S. mansoni is thought to have been imported repeatedly into the Americas during the last 500 years with the African slave trade. Surprisingly considering that the New and Old World separated 95-106 million years (Myr) ago, the disease rapidly became established due to the presence of endemic susceptible hosts. Reconstructing the phylogenetic relationships within Biomphalaria may provide insights into the successful intercontinental spread of S. mansoni. Parsimony and distance analyses of mitochondrial and nuclear sequences show African taxa to be monophyletic and Neotropical species paraphyletic, with Biomphalaria glabrata forming a separate clade from other Neotropical Biomphalaria, and ancestral to the African taxa. A west to east trans-Atlantic dispersal of a B. glabrata-like taxon, possibly as recently as the Plio-Pleistocene (1.8-3.6 Myr ago) according to a general mitochondrial clock, would fit these observations. Vicariance or an African origin for B. glabrata followed by multiple introductions to South America over the past 500 years with the African slave trade seem unlikely explanations. Knowledge of the phylogenetic relationships among important intermediate host species may prove useful in furthering control measures which exploit genetic differences in susceptibility to parasites, and in elucidating the evolution of schistosome resistance. PMID:11133023

  13. Slave mortality during the cholera epidemic in Rio de Janeiro (1855-1856): a preliminary analysis.

    PubMed

    Kodama, Kaori; Pimenta, Tânia Salgado; Bastos, Francisco Inácio; Bellido, Jaime Gregorio

    2012-12-01

    The article offers a preliminary analysis of the sociodemographic profile of deaths recorded during the first cholera epidemic in Rio de Janeiro, based on data gathered from death records at Santa Casa de Misericórdia Hospital. After cholera appeared in the country in 1855, Brazilian medical reports indicated a social bias, with slaves and the free poor suffering high mortality. From a historical perspective, however, little research has been done on the epidemic and its dynamics. The recovery of original data on cholera and the analysis of cholera mortality rates help us to better understand aspects of the slave universe in the urban zone of Rio de Janeiro in the period following the end of the slave trade.

  14. The single-chip FASTBUS Slave Interface

    SciTech Connect

    Nelson, R.O.; Machen, D.R.; Downing, R.W.

    1990-12-31

    A single-chip implementation of the general-purpose FASTBUS Slave Interface (FSI) has been developed in ECL gate-array technology. The FSI will occupy only 1.6% of the available circuit board space while providing a complete 32-bit interface to the FASTBUS. All mandatory slave-interface requirements of IEEE 960 are supported, in addition to several non-mandatory requirements and the optional, extended MS code features. Geographic, logical, and broadcast addressing are implemented using on-chip registers. An optional multiple-module addressing technique is included that allows participating modules residing on a common crate or cable segment to respond as if individually addressed in sequence. The user interface provided by the FSI allows control of slave status-response and connection timing for both address and data cycles. The BIT1 ECL array technology used for the FSI allows direct connections to the FASTBUS, eliminating the need for external driver/receiver buffers.

  15. Anthropomorphic master/slave manipulator system

    NASA Technical Reports Server (NTRS)

    Vykukal, H. C.; King, R. F.; Vallotton, W. C. (Inventor)

    1977-01-01

    An anthropomorphic master/slave manipulator system including master arm apparatus with a plurality of master tubular articulated portions is outlined. Objectives of this investion were to provide a system that accurately and smoothly simulates human limb movement at a remote location. The system has a high frequency response, a high structural stiffness and a design that protects the components of the slave mechanism. Simulation of human movements is possible in outer space, underwater, and in a hazardous environment such as in a high radiation area. The equivalent ability, dexterity, and strength of a human arm are simulated.

  16. Nutritional consequences of the African diaspora.

    PubMed

    Luke, A; Cooper, R S; Prewitt, T E; Adeyemo, A A; Forrester, T E

    2001-01-01

    Along with their foods and dietary customs, Africans were carried into diaspora throughout the Americas as a result of the European slave trade. Their descendants represent populations at varying stages of the nutrition transition. West Africans are in the early stage, where undernutrition and nutrient deficiencies are prevalent. Many Caribbean populations represent the middle stages, with undernutrition and obesity coexisting. African-Americans and black populations in the United Kingdom suffer from the consequences of caloric excess and diets high in fat and animal products. Obesity, non-insulin-dependent diabetes mellitus, hypertension, coronary heart disease, and certain cancers all follow an east-to-west gradient of increasing prevalence. Public health efforts must focus not only on eradicating undernutrition in West Africa and the Caribbean but also on preventing obesity, hypercholesterolemia, and their consequences. Fortunately, a coherent and well-supported set of recommendations exists to promote better nutrition. Implementation of it founders primarily as a result of the influence of commercial and political interests.

  17. An anthropomorphic master-slave manipulator system.

    NASA Technical Reports Server (NTRS)

    Vykukal, H. C.; King, R. F.; Vallotton, W. C.

    1973-01-01

    Review of some of the results of a teleoperator systems technology program devoted to the development of an anthropomorphic unilateral master-slave manipulator system. Following a discussion of the mechanical design details and servo design considerations, the developed system's test results are presented.

  18. Complicating Slavery: Teaching with Runaway Slave Advertisements.

    ERIC Educational Resources Information Center

    Mason, Matthew; Koman, Rita G.

    2003-01-01

    Presents a lesson plan that teaches students about slavery in the colonial United States. Focuses on the differences between slavery in the northern and southern parts of the country. Explains that the lesson includes and uses slave advertisements to teach about slavery. Offers additional resources. (CMK)

  19. Black Slave Control in the Cherokee Nation

    ERIC Educational Resources Information Center

    Halliburton, R., Jr.

    1975-01-01

    Concludes that black slavery-including slave codes-among the Cherokees was very similar to the institution in the Southern United States. This is not surprising since the Cherokees identified economically, politically, and socially with the South more than any other group. (Author/AM)

  20. Slave Labor Camps of the Third Reich.

    ERIC Educational Resources Information Center

    Stone, Adolf

    1983-01-01

    Describes the ground rules used by Nazi architects in choosing the sites for slave labor camps. While some, like Auschwitz, became extermination camps, others also produced armaments. One camp, Theresienstadt, became a "model" camp to show to reporters and Red Cross representatives. (CS)

  1. Enslaved Africans and doctors in South Carolina.

    PubMed

    Goodson, Martia Graham

    2003-03-01

    This interpretation of the relationship between enslavement and American medicine in 19th century South Carolina reveals the intimacy that existed between Africans enslaved in that state and the doctors who practiced and taught there. Enslaved Africans were resourceful and reliable medical figures in the slave community. Their knowledge of medical botany permeated the slave quarters and plantation hospitals and was appropriated into southern medical knowledge. The trajectories of the careers of three South Carolina physicians are tied to their practice around and on the enslaved. The beginnings of gynecological surgery are linked to 1840s experimentation on enslaved African women performed by one of them.

  2. Generalized slave-particle method for extended Hubbard models

    NASA Astrophysics Data System (ADS)

    Georgescu, Alexandru B.; Ismail-Beigi, Sohrab

    2015-12-01

    We introduce a set of generalized slave-particle models for extended Hubbard models that treat localized electronic correlations using slave-boson decompositions. Our models automatically include two slave-particle methods of recent interest, the slave-rotor and slave-spin methods, as well as a ladder of new intermediate models where one can choose which of the electronic degrees of freedom (e.g., spin or orbital labels) are treated as correlated degrees of freedom by the slave bosons. In addition, our method removes the aberrant behavior of the slave-rotor model, where it systematically overestimates the importance of electronic correlation effects for weak interaction strength, by removing the contribution of unphysical states from the bosonic Hilbert space. The flexibility of our formalism permits one to separate and isolate the effect of correlations on the key degrees of freedom.

  3. Male ancestry structure and interethnic admixture in African-descent communities from the Amazon as revealed by Y-chromosome Strs.

    PubMed

    Palha, Teresinha de Jesus Brabo Ferreira; Ribeiro-Rodrigues, Elzemar Martins; Ribeiro-dos-Santos, Andrea; Guerreiro, João Farias; de Moura, Luciene Soraya Souza; Santos, Sidney

    2011-03-01

    Some genetic markers on both the Y chromosome and mtDNA are highly polymorphic and population-specific in humans, representing useful tools for reconstructing the past history of populations with poor historical records. Such lack of information is usually true in the case of recent African-descent populations of the New World founded by fugitive slaves throughout the slavery period in the Americas, particularly in Brazil, where those communities are known as quilombos. Aiming to recover male-derived ethnic structure of nine quilombos from the Brazilian Amazon, a total of 300 individuals, belonging to Mazagão Velho (N = 24), Curiaú (N = 48), Mazagão (N = 36), Trombetas (N = 20), Itacoã (N = 22), Saracura (N = 46), Marajó (N = 58), Pitimandeua (N = 26), and Pontal (N = 20), were investigated for nine Y-STRs (DYS393, DYS19, DYS390, DYS389 I, DYS389 II, DYS392, DYS391, DYS385 I/II). From the 169 distinct haplotypes obtained, 120 were singletons. The results suggest the West African coast as the main origin of slaves brought to Brazil (54% of male contribution); the European contribution was high (41%), while the Amerindian's was low (5%). Those results contrast with previous mtDNA data that showed high Amerindian female contribution (46.6%) in African-descent populations. AMOVA suggests that the genetic differentiation among the quilombos is mainly influenced by admixture with European. However, when restricting AMOVA to African-specific haplotypes, low differentiation was detected, suggesting great genetic homogeneity of the African founding populations and/or a later homogenization by intense slave trade inside Brazil.

  4. Opportunities in African power generation: A business briefing for industry and investment executives. Held in Baltimore, Maryland, June 21-22, 1995. Export trade information

    SciTech Connect

    1995-06-21

    The report, prepared by the Institute of International Education, was funded by the U.S. Trade and Development Agency. The information contained in the report was compiled in part for a power generation conference held in Baltimore, Maryland. The focus of the report is the market created by electric power projects financed by multilateral development banks. The study contains country information and project profiles related to the energy sector for eleven countries: Benin, Botswana, Cote D`Ivoire, Ethiopia, Ghana, Malawi, Morocoo, Senegal, Tanzania, Zambia, and Zimbabwe. The report also outlines the range of service opportunities in the region such as consulting, engineering, construction and project management, and equipment procurement. It is divided into the following sections: (1) Agenda/Program; (2) African Energy Sector Overview; (3) Project Profiles; (4) Country Information; and (5) Attendees.

  5. Gabor fusion master slave optical coherence tomography

    PubMed Central

    Cernat, Ramona; Bradu, Adrian; Israelsen, Niels Møller; Bang, Ole; Rivet, Sylvain; Keane, Pearse A.; Heath, David-Garway; Rajendram, Ranjan; Podoleanu, Adrian

    2017-01-01

    This paper describes the application of the Gabor filtering protocol to a Master/Slave (MS) swept source optical coherence tomography (SS)-OCT system at 1300 nm. The MS-OCT system delivers information from selected depths, a property that allows operation similar to that of a time domain OCT system, where dynamic focusing is possible. The Gabor filtering processing following collection of multiple data from different focus positions is different from that utilized by a conventional swept source OCT system using a Fast Fourier transform (FFT) to produce an A-scan. Instead of selecting the bright parts of A-scans for each focus position, to be placed in a final B-scan image (or in a final volume), and discarding the rest, the MS principle can be employed to advantageously deliver signal from the depths within each focus range only. The MS procedure is illustrated on creating volumes of data of constant transversal resolution from a cucumber and from an insect by repeating data acquisition for 4 different focus positions. In addition, advantage is taken from the tolerance to dispersion of the MS principle that allows automatic compensation for dispersion created by layers above the object of interest. By combining the two techniques, Gabor filtering and Master/Slave, a powerful imaging instrument is demonstrated. The master/slave technique allows simultaneous display of three categories of images in one frame: multiple depth en-face OCT images, two cross-sectional OCT images and a confocal like image obtained by averaging the en-face ones. We also demonstrate the superiority of MS-OCT over its FFT based counterpart when used with a Gabor filtering OCT instrument in terms of the speed of assembling the fused volume. For our case, we show that when more than 4 focus positions are required to produce the final volume, MS is faster than the conventional FFT based procedure. PMID:28270987

  6. Gabor fusion master slave optical coherence tomography.

    PubMed

    Cernat, Ramona; Bradu, Adrian; Israelsen, Niels Møller; Bang, Ole; Rivet, Sylvain; Keane, Pearse A; Heath, David-Garway; Rajendram, Ranjan; Podoleanu, Adrian

    2017-02-01

    This paper describes the application of the Gabor filtering protocol to a Master/Slave (MS) swept source optical coherence tomography (SS)-OCT system at 1300 nm. The MS-OCT system delivers information from selected depths, a property that allows operation similar to that of a time domain OCT system, where dynamic focusing is possible. The Gabor filtering processing following collection of multiple data from different focus positions is different from that utilized by a conventional swept source OCT system using a Fast Fourier transform (FFT) to produce an A-scan. Instead of selecting the bright parts of A-scans for each focus position, to be placed in a final B-scan image (or in a final volume), and discarding the rest, the MS principle can be employed to advantageously deliver signal from the depths within each focus range only. The MS procedure is illustrated on creating volumes of data of constant transversal resolution from a cucumber and from an insect by repeating data acquisition for 4 different focus positions. In addition, advantage is taken from the tolerance to dispersion of the MS principle that allows automatic compensation for dispersion created by layers above the object of interest. By combining the two techniques, Gabor filtering and Master/Slave, a powerful imaging instrument is demonstrated. The master/slave technique allows simultaneous display of three categories of images in one frame: multiple depth en-face OCT images, two cross-sectional OCT images and a confocal like image obtained by averaging the en-face ones. We also demonstrate the superiority of MS-OCT over its FFT based counterpart when used with a Gabor filtering OCT instrument in terms of the speed of assembling the fused volume. For our case, we show that when more than 4 focus positions are required to produce the final volume, MS is faster than the conventional FFT based procedure.

  7. Accretion of the Archean Slave Province

    NASA Technical Reports Server (NTRS)

    Kusky, Timothy

    1988-01-01

    Detailed field studies of selected areas in the greenstone belts of the Slave Province of Canada were presented. This area was long cited as a type area by supporters of the (now generally abandoned) rift model of greenstone belts. It was shown that a plate tectonic interpretation accounted more successfully for the regional geology and identified four terranes that had experienced complex divergent and convergent histories between 2.7 and 3.4 Ga. A dismembered ophiolite was identified and a late episode of widespread granitic intrusion was recognized.

  8. U.S. Trade and Investment Relationship with Sub-Saharan Africa: The African Growth and Opportunity Act

    DTIC Science & Technology

    2009-07-24

    Indebted Poor Countries Initiative (HIPC), the Multilateral Debt Relief Initiative (MDRI), and the Paris Club agreement with Nigeria .25 U.S.-Africa Trade...the region were from three SSA countries in 2008: Nigeria (44%), Angola (22%), and South Africa (12%). Exports were similarly concentrated, with three...7 receiving 68%: South Africa (34%), Nigeria (22%), and Angola (12%). The remaining countries each accounted for less than 6% of U.S. exports to the

  9. A Review of the Conflicting Theories on the Slave Family.

    ERIC Educational Resources Information Center

    Davis, David Brion

    1997-01-01

    Historians' changing perceptions of the quality of slave family life are reviewed as they developed from World War I to the present day, noting the paternalism that marked historians' thinking in post-War period, and the romanticism that characterizes some later writings. Controversy over slave family structures continues in present-day studies.…

  10. Thomas Jefferson and Slaves: Teaching an American Paradox. Lesson Plan.

    ERIC Educational Resources Information Center

    Fehn, Bruce

    2000-01-01

    Provides 11 primary sources that enable students to contemplate how Thomas Jefferson and his slaves produced a culture and community at Monticello (Virginia) and his other plantations. Focuses on Jefferson's relationship with his slaves, particularly addressing Sally Hemming's relationship with Jefferson, in order to study the complicated history…

  11. Using Slave Advertisements as Historical Evidence: A Lesson in Discovery.

    ERIC Educational Resources Information Center

    Harper, C. W.

    1992-01-01

    Suggests that slave advertisements from old southern newspapers can be used to help teachers convey the nature of slavery. Includes a selection of slave advertisements with analysis and questions for discussion. Recommends the use of such advertisements for units on the causes of the Civil War or the lingering effects of slavery on society today.…

  12. SLAVE QUARTERS (RESTORED). This is the north building, one of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SLAVE QUARTERS (RESTORED). This is the north building, one of the two identical buildings in the plantation. Each building has a 2-room plan. - Hopsewee Plantation, Slave Quarters, U.S. Routes 17 & 701, Santee River, North, Georgetown, Georgetown County, SC

  13. Agonistic Struggle: Master-Slave Dialogues in Humanities Supervision

    ERIC Educational Resources Information Center

    Grant, Barbara M.

    2008-01-01

    Hegel's master and slave is a significant archetype for graduate research supervision. The master-slave relation vividly exemplifies the hierarchical bond that ties supervisor and student together. Such a confronting view of supervision provides a counterbalance to contemporary emphases on equality between supervisor and student. In what follows,…

  14. The American Slave Narrative: Dramatic Resource Material for the Classroom.

    ERIC Educational Resources Information Center

    Polsky, Milton E.

    Examples from American slave narratives offer demonstrative evidence that slave biographies and autobiographies deal with the worthwhile theme of the denial of and struggle for freedom and contain exciting adventure plots consisting of mystery, romance, risk-taking and disguises. Characters striving for freedom exhibit positive traits such as…

  15. African American History as Depicted in Recently Published Children's Books

    ERIC Educational Resources Information Center

    Lamme, Linda Leonard; Astengo, Be; Lowery, Ruth McCoy; Masla, Diane; Russo, Roseanne; Savage, Debbie; Shelton, Nancy Rankie

    2002-01-01

    Exciting stories about African Americans in recently published historical fiction books for children concern Pea Island Life-Station, a private school for African American girls, a biracial slave, a black woman who homesteads for land in 1889, and an orphan who travels on his own to Flint, Michigan, during the Depression. Much of this history…

  16. Use and Misuse of Speech Diagnostics for African American Students

    ERIC Educational Resources Information Center

    Baugh, John

    2015-01-01

    Many African American students have been tested using speech pathology diagnostics that are ill suited to their distinctive linguistic circumstances. Slave descendants of African origin share a unique linguistic heritage in contrast and comparison to every other immigrant group residing within America. In an effort to overcome the legacy of…

  17. Phanerozoic surface history of the Slave craton

    NASA Astrophysics Data System (ADS)

    Ault, Alexis K.; Flowers, Rebecca M.; Bowring, Samuel A.

    2013-09-01

    apatite (U-Th)/He (AHe) thermochronometry data and key geologic constraints from Slave craton kimberlites are used to develop a model for the Phanerozoic burial, unroofing, and hypsometric history of the northwestern Canadian shield. AHe dates range from 210 ± 13 to 382 ± 79 Ma, are older in the eastern Slave craton and decrease westward, and resolve the spatial extent, thickness, and history of now-denuded sedimentary units. Results indicate Paleozoic heating to temperatures ≥85-90°C, suggesting regional burial beneath ≥2.8 km of strata while the region was at sea level, followed by the westward migration of unroofing across the craton. This Paleozoic-Mesozoic history does not correlate with sea level change, instead requiring Paleozoic subsidence of the craton followed by surface uplift. The AHe data restrict Cretaceous burial to ≤1.6 km, followed by unroofing, Eocene terrestrial sediment deposition, and removal of Phanerozoic sedimentary cover across the region by present day. The craton underwent ≥300 m of post-100 Ma elevation gain, based on ~100 Ma marine sedimentary xenoliths entrained in ~75-45 Ma kimberlites at modern elevations of 550-600 m. The transition from Paleozoic-Mesozoic subsidence to surface uplift may signal a change from predominantly northern (Franklinian-Innuitian) to western (Canadian Cordillera) plate boundary controls on continental interior processes, with the latter driving the east-to-west wave of unroofing. Canadian Cordillera evolution also affected the Cretaceous-early Tertiary history. Dynamic topography due to changing mantle flow regimes and proximity to sediment sources influenced the Phanerozoic surface evolution of the northwestern Canadian shield.

  18. Synchronization Analysis of Master-Slave Probabilistic Boolean Networks

    NASA Astrophysics Data System (ADS)

    Lu, Jianquan; Zhong, Jie; Li, Lulu; Ho, Daniel W. C.; Cao, Jinde

    2015-08-01

    In this paper, we analyze the synchronization problem of master-slave probabilistic Boolean networks (PBNs). The master Boolean network (BN) is a deterministic BN, while the slave BN is determined by a series of possible logical functions with certain probability at each discrete time point. In this paper, we firstly define the synchronization of master-slave PBNs with probability one, and then we investigate synchronization with probability one. By resorting to new approach called semi-tensor product (STP), the master-slave PBNs are expressed in equivalent algebraic forms. Based on the algebraic form, some necessary and sufficient criteria are derived to guarantee synchronization with probability one. Further, we study the synchronization of master-slave PBNs in probability. Synchronization in probability implies that for any initial states, the master BN can be synchronized by the slave BN with certain probability, while synchronization with probability one implies that master BN can be synchronized by the slave BN with probability one. Based on the equivalent algebraic form, some efficient conditions are derived to guarantee synchronization in probability. Finally, several numerical examples are presented to show the effectiveness of the main results.

  19. Synchronization Analysis of Master-Slave Probabilistic Boolean Networks

    PubMed Central

    Lu, Jianquan; Zhong, Jie; Li, Lulu; Ho, Daniel W. C.; Cao, Jinde

    2015-01-01

    In this paper, we analyze the synchronization problem of master-slave probabilistic Boolean networks (PBNs). The master Boolean network (BN) is a deterministic BN, while the slave BN is determined by a series of possible logical functions with certain probability at each discrete time point. In this paper, we firstly define the synchronization of master-slave PBNs with probability one, and then we investigate synchronization with probability one. By resorting to new approach called semi-tensor product (STP), the master-slave PBNs are expressed in equivalent algebraic forms. Based on the algebraic form, some necessary and sufficient criteria are derived to guarantee synchronization with probability one. Further, we study the synchronization of master-slave PBNs in probability. Synchronization in probability implies that for any initial states, the master BN can be synchronized by the slave BN with certain probability, while synchronization with probability one implies that master BN can be synchronized by the slave BN with probability one. Based on the equivalent algebraic form, some efficient conditions are derived to guarantee synchronization in probability. Finally, several numerical examples are presented to show the effectiveness of the main results. PMID:26315380

  20. Synchronization Analysis of Master-Slave Probabilistic Boolean Networks.

    PubMed

    Lu, Jianquan; Zhong, Jie; Li, Lulu; Ho, Daniel W C; Cao, Jinde

    2015-08-28

    In this paper, we analyze the synchronization problem of master-slave probabilistic Boolean networks (PBNs). The master Boolean network (BN) is a deterministic BN, while the slave BN is determined by a series of possible logical functions with certain probability at each discrete time point. In this paper, we firstly define the synchronization of master-slave PBNs with probability one, and then we investigate synchronization with probability one. By resorting to new approach called semi-tensor product (STP), the master-slave PBNs are expressed in equivalent algebraic forms. Based on the algebraic form, some necessary and sufficient criteria are derived to guarantee synchronization with probability one. Further, we study the synchronization of master-slave PBNs in probability. Synchronization in probability implies that for any initial states, the master BN can be synchronized by the slave BN with certain probability, while synchronization with probability one implies that master BN can be synchronized by the slave BN with probability one. Based on the equivalent algebraic form, some efficient conditions are derived to guarantee synchronization in probability. Finally, several numerical examples are presented to show the effectiveness of the main results.

  1. The history of introduction of the African baobab (Adansonia digitata, Malvaceae: Bombacoideae) in the Indian subcontinent.

    PubMed

    Bell, Karen L; Rangan, Haripriya; Kull, Christian A; Murphy, Daniel J

    2015-09-01

    To investigate the pathways of introduction of the African baobab, Adansonia digitata, to the Indian subcontinent, we examined 10 microsatellite loci in individuals from Africa, India, the Mascarenes and Malaysia, and matched this with historical evidence of human interactions between source and destination regions. Genetic analysis showed broad congruence of African clusters with biogeographic regions except along the Zambezi (Mozambique) and Kilwa (Tanzania), where populations included a mixture of individuals assigned to at least two different clusters. Individuals from West Africa, the Mascarenes, southeast India and Malaysia shared a cluster. Baobabs from western and central India clustered separately from Africa. Genetic diversity was lower in populations from the Indian subcontinent than in African populations, but the former contained private alleles. Phylogenetic analysis showed Indian populations were closest to those from the Mombasa-Dar es Salaam coast. The genetic results provide evidence of multiple introductions of African baobabs to the Indian subcontinent over a longer time period than previously assumed. Individuals belonging to different genetic clusters in Zambezi and Kilwa may reflect the history of trafficking captives from inland areas to supply the slave trade between the fifteenth and nineteenth centuries. Baobabs in the Mascarenes, southeast India and Malaysia indicate introduction from West Africa through eighteenth and nineteenth century European colonial networks.

  2. The history of introduction of the African baobab (Adansonia digitata, Malvaceae: Bombacoideae) in the Indian subcontinent

    PubMed Central

    Bell, Karen L.; Rangan, Haripriya; Kull, Christian A.; Murphy, Daniel J.

    2015-01-01

    To investigate the pathways of introduction of the African baobab, Adansonia digitata, to the Indian subcontinent, we examined 10 microsatellite loci in individuals from Africa, India, the Mascarenes and Malaysia, and matched this with historical evidence of human interactions between source and destination regions. Genetic analysis showed broad congruence of African clusters with biogeographic regions except along the Zambezi (Mozambique) and Kilwa (Tanzania), where populations included a mixture of individuals assigned to at least two different clusters. Individuals from West Africa, the Mascarenes, southeast India and Malaysia shared a cluster. Baobabs from western and central India clustered separately from Africa. Genetic diversity was lower in populations from the Indian subcontinent than in African populations, but the former contained private alleles. Phylogenetic analysis showed Indian populations were closest to those from the Mombasa-Dar es Salaam coast. The genetic results provide evidence of multiple introductions of African baobabs to the Indian subcontinent over a longer time period than previously assumed. Individuals belonging to different genetic clusters in Zambezi and Kilwa may reflect the history of trafficking captives from inland areas to supply the slave trade between the fifteenth and nineteenth centuries. Baobabs in the Mascarenes, southeast India and Malaysia indicate introduction from West Africa through eighteenth and nineteenth century European colonial networks. PMID:26473060

  3. Aerosol chemical and radiative properties in the tropical Atlantic trade winds: The importance of African mineral dust

    NASA Astrophysics Data System (ADS)

    Li-Jones, Xu

    This dissertation presents results relevant to aerosol radiative forcing. The focus of this dissertation is the role of mineral dust in atmospheric radiative processes over the tropical Atlantic Ocean. The aerosol mass and light scattering data concurrently measured over the tropical North Atlantic ocean yield a dust mass scattering efficiency of 0.77 m2/g, about a quarter of that measured for non-sea-salt sulfate (nss SO4=) in the North Atlantic marine boundary layer. Because of the high concentration of mineral dust relative to nss SO4= over the tropical North Atlantic, the total scattering by mineral dust is about four times that by nss SO4 = aerosol in this region. On an annual basis, aerosol optical depth is apportioned to: mineral dust 71%, nss- SO4 = 16% and sea salt 13%. The coarse-particle fraction (CPF) (aerodynamic diameter > 1 μm) of nss SO4= varied from about 21% to 73%, with the highest CPF values associated with African dust events. The CPF nss SO 4= was believed to be a result of the heterogeneous reactions of SO2 (presumably from European sources) with dust particles suspended in the air over North Africa. This study provides the first direct evidence that confirms the importance of dust in sulfate production and resulting the coarse particle sulfate in the tropical Atlantic Ocean region. An important implication is that dust particles may reduce the effectiveness of sulfate aerosol as a radiative forcing agent in many regions where dust events are frequent and where dust concentrations are high. The aerosol scattering coefficient (ASC) measured during this experiment increased by a factor of 1.13 to 1.69 when RH was increased from about 40% to 80%. Through chemical apportioning of ASC, the HGF for sea-salt was found to be 1.8 +/- 0.2, while that of mineral dust was close to unity. This study shows that climate studies must consider the effect of mineral dust not only because of its direct effects on the radiation balance but also because of its

  4. Particle size distributions of Trade-Wind African dust measured in the air and after dispersal in water

    NASA Astrophysics Data System (ADS)

    Prospero, J. M.; Custals, L.

    2012-12-01

    the large seasonal changes in particle size characteristics to changes in dust source region; in winter-spring dust sources appear to be most active in the Sahel region of North Africa while in summer the larger Sahara becomes dominant. Measurements of particles on impactor stages confirm that particles are highly agglomerated, most likely as a large core particle serving as the host for smaller particles (rather than massive clumps of smaller particles). It is notable that in Miami during summer dust episodes the measurements of dust size properties are identical to those in Barbados. In other times of year in Miami there is, in effect, no significant dust signature except for greatly increased concentrations of relatively large particles which yield a noisy pattern that suggests a local or regional source. Our results thus far yield African dust size distributions that are broadly consistent with those reported for Greenland ice cores. We seek to identify the possible causes in the observed size shifts, focusing on large dust events, and to relate each event with a specific source region (using remote sensing products) and meteorological conditions.

  5. Diet and long-term health: an African Diaspora perspective.

    PubMed

    Solomons, Noel W

    2003-01-01

    The life-stage approach, which views the behaviours and exposures of an individual from the preconceptual situation of the parent through pregnancy, infancy, childhood and adolescence, and into the advancing years through adulthood, is the basis of analysis of strategies to improve long-term health. Among the behaviours of note is the dietary selection pattern, conditioning our exposure to nutrients and dietary constituents that influences growth, nutriture, cognitive and physical performance, and disease resistance and susceptibility. The African Diaspora created a population displaced from Africa to the Western Hemisphere as part of the African slave trade from the 16th to 18th centuries. It continues to manifest distinct dietary and lifestyle practices in the context of a health experience that is different both from the population in their African countries of origin and from the other ethnicities in their countries of displacement and current residence. Afro-Americans are more susceptible to a series of diseases and conditions including low birth weight, violence, and HIV/AIDS, as well as the non-communicable diseases: obesity, diabetes mellitus, cardiovascular disease, hypertension, stroke, renal failure, breast cancer, prostate cancer and lead poisoning. The differential nature of dietary practices are conditioned at times by the poverty and marginalisation of the populace, resulting in either disadvantageous or beneficial outcomes relative to others' eating habits. Serious consideration must be given to the possibility that ethnic difference give rise to different requirements and tolerances for essential nutrients and distinct protective or adverse responses to foods and dietary substances. The major challenges to health improvement for the African Diaspora is coming to grips with the policy and programmatic nuances of differential treatment and the effecting the behavioural changes that would be needed in a population skeptical of the motives of media and

  6. Y-chromosome R-M343 African lineages and sickle cell disease reveal structured assimilation in Lebanon.

    PubMed

    Haber, Marc; Platt, Daniel E; Khoury, Simon; Badro, Danielle A; Abboud, Miguel; Tyler-Smith, Chris; Zalloua, Pierre A

    2011-01-01

    We have sought to identify signals of assimilation of African male lines in Lebanon by exploring the association of sickle cell disease (SCD) in Lebanon with Y-chromosome haplogroups that are informative of the disease origin and its exclusivity to the Muslim community. A total of 732 samples were analyzed, including 33 SCD patients from Lebanon genotyped for 28 binary markers and 19 short tandem repeats on the non-recombinant segment of the Y chromosome. Genetic organization was identified using populations known to have influenced the genetic structure of the Lebanese population, in addition to African populations with high incidence of SCD. Y-chromosome haplogroup R-M343 sub-lineages distinguish between sub-Saharan African and Lebanese Y chromosomes. We detected a limited penetration of SCD into Lebanese R-M343 carriers, restricted to Lebanese Muslims. We suggest that this penetration brought the sickle cell gene along with the African R-M343, probably with the Saharan caravan slave trade.

  7. Modeling Correlation Effects in Nickelates with Slave Particles

    NASA Astrophysics Data System (ADS)

    Georgescu, Alexandru Bogdan; Ismail-Beigi, Sohrab

    Nickelate interfaces display interesting electronic properties including orbital ordering similar to that of cuprate superconductors and thickness dependent metal-insulator transitions. One-particle band theory calculations do not include dynamic localized correlation effects on the nickel sites and thus often incorrectly predict metallic systems or incorrect ARPES spectra. Building on two previous successful slave-particle treatments of local correlations, we present a generalized slave-particle method that includes prior models and allows us to produce new intermediate models. The computational efficiency of these slave-boson methods means that one can readily study correlation effects in complex heterostructures. We show some predictions of these methods for the electronic structure of bulk and thin film nickelates. Work supported by NSF Grant MRSEC DMR-1119826.

  8. Two-arm master/slave manipulator for nuclear facilities

    SciTech Connect

    Tomizawa, F.; Iwatsuka, N.; Suzuki, M.; Senoh, M.; Sugiyama, S.

    1988-01-01

    Several kinds of one-arm manipulators have been developed for remote maintenance in nuclear facilities to reduce personnel radiation exposure and to keep plant availability as high as possible. In those maintenance tasks, however, there are many that need two arms, e.g., one arm holds the work object and the other arm cuts it with a plasma torch. To answer this need, a dexterous two-arm master/slave manipulator has been developed based on the technology for one-arm manipulators. A prototype two-arm/slave manipulator is shown. The specifications for master and slave manipulators are listed. The prototype two-arm manipulator is undergoing laboratory performance tests. Preliminary results showed the maximum static operating forces were 0.4 N for the all-direct drive (DD)-type arm and 1.1 N for the semi-DD type. The payload for each arm of the slave manipulator was confirmed as 10 kg/sub f/, using mock pieces. The decommissioning tasks of cutting pipes and steel plates were successfully carried out.

  9. Slave Advertising in the Colonial Newspaper: Mirror to the Dilemma.

    ERIC Educational Resources Information Center

    Bradley, Patricia

    To explore racial attitudes from the colonial period of the United States, a study examined advertising practices regarding announcements dealing with black slaves in colonial newspapers in Massachusetts, New York, Pennsylvania, Maryland, Virginia, and South Carolina. Careful scrutiny revealed no relationship between the editorial stance of a…

  10. The influence of feeding on the evolution of sensory signals: a comparative test of an evolutionary trade-off between masticatory and sensory functions of skulls in southern African horseshoe bats (Rhinolophidae).

    PubMed

    Jacobs, D S; Bastian, A; Bam, L

    2014-12-01

    The skulls of animals have to perform many functions. Optimization for one function may mean another function is less optimized, resulting in evolutionary trade-offs. Here, we investigate whether a trade-off exists between the masticatory and sensory functions of animal skulls using echolocating bats as model species. Several species of rhinolophid bats deviate from the allometric relationship between body size and echolocation frequency. Such deviation may be the result of selection for increased bite force, resulting in a decrease in snout length which could in turn lead to higher echolocation frequencies. If so, there should be a positive relationship between bite force and echolocation frequency. We investigated this relationship in several species of southern African rhinolophids using phylogenetically informed analyses of the allometry of their bite force and echolocation frequency and of the three-dimensional shape of their skulls. As predicted, echolocation frequency was positively correlated with bite force, suggesting that its evolution is influenced by a trade-off between the masticatory and sensory functions of the skull. In support of this, variation in skull shape was explained by both echolocation frequency (80%) and bite force (20%). Furthermore, it appears that selection has acted on the nasal capsules, which have a frequency-specific impedance matching function during vocalization. There was a negative correlation between echolocation frequency and capsule volume across species. Optimization of the masticatory function of the skull may have been achieved through changes in the shape of the mandible and associated musculature, elements not considered in this study.

  11. System for simultaneously loading program to master computer memory devices and corresponding slave computer memory devices

    NASA Technical Reports Server (NTRS)

    Hall, William A. (Inventor)

    1993-01-01

    A bus programmable slave module card for use in a computer control system is disclosed which comprises a master computer and one or more slave computer modules interfacing by means of a bus. Each slave module includes its own microprocessor, memory, and control program for acting as a single loop controller. The slave card includes a plurality of memory means (S1, S2...) corresponding to a like plurality of memory devices (C1, C2...) in the master computer, for each slave memory means its own communication lines connectable through the bus with memory communication lines of an associated memory device in the master computer, and a one-way electronic door which is switchable to either a closed condition or a one-way open condition. With the door closed, communication lines between master computer memory (C1, C2...) and slave memory (S1, S2...) are blocked. In the one-way open condition invention, the memory communication lines or each slave memory means (S1, S2...) connect with the memory communication lines of its associated memory device (C1, C2...) in the master computer, and the memory devices (C1, C2...) of the master computer and slave card are electrically parallel such that information seen by the master's memory is also seen by the slave's memory. The slave card is also connectable to a switch for electronically removing the slave microprocessor from the system. With the master computer and the slave card in programming mode relationship, and the slave microprocessor electronically removed from the system, loading a program in the memory devices (C1, C2...) of the master accomplishes a parallel loading into the memory devices (S1, S2...) of the slave.

  12. X-slave boson approach to the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Franco, R.; Figueira, M. S.; Foglio, M. E.

    2001-05-01

    The periodic anderson model (PAM) in the limit U=∞, can be studied by employing the Hubbard X operators to project out the unwanted states. In a previous work, we have studied the cumulant expansion of this Hamiltonian employing the hybridization as a perturbation, but probability conservation of the local states (completeness) is not usually satisfied when partial expansions like the "chain approximation (CHA)" are employed. To consider this problem, we use a technique similar to the one employed by Coleman to treat the same problem with slave-bosons in the mean-field approximation. Assuming a particular renormalization for hybridization, we obtain a description that avoids an unwanted phase transition that appears in the mean-field slave-boson method at intermediate temperatures.

  13. Slave fermion formalism for the tetrahedral spin chain

    NASA Astrophysics Data System (ADS)

    Mohan, Priyanka; Rao, Sumathi

    2016-09-01

    We use the SU(2) slave fermion approach to study a tetrahedral spin 1/2 chain, which is a one-dimensional generalization of the two dimensional Kitaev honeycomb model. Using the mean field theory, coupled with a gauge fixing procedure to implement the single occupancy constraint, we obtain the phase diagram of the model. We then show that it matches the exact results obtained earlier using the Majorana fermion representation. We also compute the spin-spin correlation in the gapless phase and show that it is a spin liquid. Finally, we map the one-dimensional model in terms of the slave fermions to the model of 1D p-wave superconducting model with complex parameters and show that the parameters of our model fall in the topological trivial regime and hence does not have edge Majorana modes.

  14. Controller arm for a remotely related slave arm

    NASA Technical Reports Server (NTRS)

    Salisbury, J. K., Jr. (Inventor)

    1979-01-01

    A segmented controller arm configured and dimensioned to form a miniature kinematic replica of a remotely related slave arm is disclosed. The arm includes: (1) a plurality of joints for affording segments of the arm simultaneous angular displacement about a plurality of pairs of intersecting axes, (2) a plurality of position sensing devices for providing electrical signals indicative of angular displacement imparted to corresponding segments of the controller shaft about the axes, and (3) a control signal circuit for generating control signals to be transmitted to the slave arm. The arm is characterized by a plurality of yokes, each being supported for angular displacement about a pair of orthogonally related axes and counterbalanced against gravitation by a cantilevered mass.

  15. Master slave manipulator maintenance at the Defense Waste Processing Facility

    SciTech Connect

    Lethco, A.J.; Beasley, K.M.

    1991-12-31

    Equipment has been developed and tested to provide transport, installation, removal, decontamination, and repair for the master slave manipulators that are required for thirty-five discrete work locations in the 221-S Vitrification Building of the Defense Waste Processing Facility at the Westinghouse Savannah River Company. This specialized equipment provides a standardized scheme for work locations at different elevations with two types of manipulators.

  16. Master slave manipulator maintenance at the Defense Waste Processing Facility

    SciTech Connect

    Lethco, A.J.; Beasley, K.M.

    1991-01-01

    Equipment has been developed and tested to provide transport, installation, removal, decontamination, and repair for the master slave manipulators that are required for thirty-five discrete work locations in the 221-S Vitrification Building of the Defense Waste Processing Facility at the Westinghouse Savannah River Company. This specialized equipment provides a standardized scheme for work locations at different elevations with two types of manipulators.

  17. The Genetic Ancestry of African Americans, Latinos, and European Americans across the United States

    PubMed Central

    Bryc, Katarzyna; Durand, Eric Y.; Macpherson, J. Michael; Reich, David; Mountain, Joanna L.

    2015-01-01

    Over the past 500 years, North America has been the site of ongoing mixing of Native Americans, European settlers, and Africans (brought largely by the trans-Atlantic slave trade), shaping the early history of what became the United States. We studied the genetic ancestry of 5,269 self-described African Americans, 8,663 Latinos, and 148,789 European Americans who are 23andMe customers and show that the legacy of these historical interactions is visible in the genetic ancestry of present-day Americans. We document pervasive mixed ancestry and asymmetrical male and female ancestry contributions in all groups studied. We show that regional ancestry differences reflect historical events, such as early Spanish colonization, waves of immigration from many regions of Europe, and forced relocation of Native Americans within the US. This study sheds light on the fine-scale differences in ancestry within and across the United States and informs our understanding of the relationship between racial and ethnic identities and genetic ancestry. PMID:25529636

  18. The genetic ancestry of African Americans, Latinos, and European Americans across the United States.

    PubMed

    Bryc, Katarzyna; Durand, Eric Y; Macpherson, J Michael; Reich, David; Mountain, Joanna L

    2015-01-08

    Over the past 500 years, North America has been the site of ongoing mixing of Native Americans, European settlers, and Africans (brought largely by the trans-Atlantic slave trade), shaping the early history of what became the United States. We studied the genetic ancestry of 5,269 self-described African Americans, 8,663 Latinos, and 148,789 European Americans who are 23andMe customers and show that the legacy of these historical interactions is visible in the genetic ancestry of present-day Americans. We document pervasive mixed ancestry and asymmetrical male and female ancestry contributions in all groups studied. We show that regional ancestry differences reflect historical events, such as early Spanish colonization, waves of immigration from many regions of Europe, and forced relocation of Native Americans within the US. This study sheds light on the fine-scale differences in ancestry within and across the United States and informs our understanding of the relationship between racial and ethnic identities and genetic ancestry.

  19. Managing the hair and skin of African American pediatric patients.

    PubMed

    Smith, W; Burns, C

    1999-01-01

    In Africa, the ancestral home of most African Americans, hair is viewed as the epitome of beauty. However, when Africans were brought to America as slaves, they were unable to care for their hair and skin adequately and were exposed to the predominant white culture, which valued straight hair and light skin. As a result, many African Americans lost self-esteem because of the characteristics of their hair and skin. In this article we examine the anatomic and physiologic features of African American hair and skin and typical African American hair and skin care practices. Common African American hair and skin disorders and their management are discussed. The goal of this article is to help primary care providers understand the special hair and skin care required for African American children (as well as other dark-skinned patients). With good patient education, understanding one's own hair and skin characteristics can also support positive self-esteem.

  20. "Why Wait Years to Become Something?" Low-Income African American Youth and the Costly Career Search in For-Profit Trade Schools

    ERIC Educational Resources Information Center

    Holland, Megan M.; DeLuca, Stefanie

    2016-01-01

    Increasing numbers of low-income and minority youth are now pursuing shorter-duration sub-baccalaureate credentials at for-profit trade and technical schools. However, many students drop out of these schools, leaving with large debts and few job prospects. Despite these dismal outcomes, we know very little about students' experiences in for-profit…

  1. Force-reflecting control of a teleoperated system coupling a nonredundant master with a redundant slave

    SciTech Connect

    Kress, R.; Jansen, J.; DePiero, F.; Babcock, S.

    1990-01-01

    A bilateral, force-reflecting controller was formulated for a 6- Degree-of-Freedom (6-DOF) master operating a 7-DOF slave. Six degrees of freedom are required to arbitrarily position and orient a manipulator and effector. A 7-DOF slave manipulator is desirable because the additional (or redundant) degree of freedom potentially allows for an infinite number of manipulator configurations for a given end effector position and orientation, thus permitting the manipulator to reach around obstacles to perform a task, to avoid joint limits, or to optimize its confinguration in some other manner. A master/slave control system was formulated using a stiffness controller for the master and a gradient-projection algorithm for the slave. The complete control system provides scaled position tracking and indexing between slave and master and force reflection between master and slave. 11 refs., 1 fig.

  2. Transthyretin V122I (pV142I)* cardiac amyloidosis: an age-dependent autosomal dominant cardiomyopathy too common to be overlooked as a cause of significant heart disease in elderly African Americans.

    PubMed

    Buxbaum, Joel N; Ruberg, Frederick L

    2017-01-19

    Since the identification of a valine-to-isoleucine substitution at position 122 (TTR V122I; pV142I) in the transthyretin (TTR)-derived fibrils extracted from the heart of a patient with late-onset cardiac amyloidosis, it has become clear that the amyloidogenic mutation and the disease occur almost exclusively in individuals of identifiable African descent. In the United States, the amyloidogenic allele frequency is 0.0173 and is carried by 3.5% of community-dwelling African Americans. Genotyping across Africa indicates that the origin of the allele is in the West African countries that were the major source of the slave trade to North America. At autopsy, the allele was found to be associated with cardiac TTR amyloid deposition in all the carriers after age 65 years; however, the clinical penetrance varies, resulting in substantial heart disease in some carriers and few symptoms in others. The allele has been found in 10% of African Americans older than age 65 with severe congestive heart failure. At this time there are potential forms of therapy in clinical trials. The combination of a highly accurate genetic test and the potential for specific therapy demands a greater awareness of this autosomal dominant, age-dependent cardiac disease in the cardiology community.Genet Med advance online publication 19 January 2017Genetics in Medicine (2017); doi:10.1038/gim.2016.200.

  3. Criminals and Insurgents: The Role of Ethnicity in State Responses to Internal Resource Competitors

    DTIC Science & Technology

    2007-06-01

    and other European slave trading powers.46 Following Britain’s banning of the slave trade in 1807, the focus shifted to the cultivation of palm oil ...Westview Press, 2000), 119-122. 47 Martin Lynn, “The West African Palm Oil Trade” in Robin Law (ed.) From Slave Trade to Legitimate Commerce...Cambridge: Cambridge University Press, 1995), 23-25. 19 previously colluded in the slave trade found new opportunities in exporting palm oil . The chiefs of

  4. The health of the American slave examined by means of Union Army medical statistics.

    PubMed

    Freemon, F R

    1985-01-01

    The health status of the American slave in the 19th century remains unclear despite extensive historical research. Better knowledge of slave health would provide a clearer picture of the life of the slave, a better understanding of the 19th-century medicine, and possibly even clues to the health problems of modern blacks. This article hopes to contribute to the literature by examining another source of data. Slaves entering the Union Army joined an organization with standardized medical care that generated extensive statistical information. Review of these statistics answers questions about the health of young male blacks at the time American slavery ended.

  5. A genome-wide search for type 2 diabetes susceptibility genes in West Africans: the Africa America Diabetes Mellitus (AADM) Study.

    PubMed

    Rotimi, Charles N; Chen, Guanjie; Adeyemo, Adebowale A; Furbert-Harris, Paulette; Parish-Gause, Debra; Zhou, Jie; Berg, Kate; Adegoke, Olufemi; Amoah, Albert; Owusu, Samuel; Acheampong, Joseph; Agyenim-Boateng, Kofi; Eghan, Benjamin A; Oli, Johnnie; Okafor, Godfrey; Ofoegbu, Ester; Osotimehin, Babatunde; Abbiyesuku, Fayeofori; Johnson, Thomas; Rufus, Theresa; Fasanmade, Olufemi; Kittles, Rick; Daniel, Harold; Chen, Yuanxiu; Dunston, Georgia; Collins, Francis S; Guass, Debra

    2004-03-01

    The incidence of type 2 diabetes is growing rapidly, not only in developed countries but also worldwide. We chose to study type 2 diabetes in West Africa, where diabetes is less common than in the U.S., reasoning that in an environment where calories are less abundant, incident cases of type 2 diabetes might carry a proportionately greater genetic component. Through the Africa America Diabetes Mellitus (AADM) study, we carried out a genome-wide linkage analysis of type 2 diabetes in a cohort of 343 affected sibling pairs (691 individuals) enrolled from five West African centers in two countries (Ghana: Accra and Kumasi; Nigeria: Enugu, Ibadan, and Lagos). A total of 390 polymorphic markers were genotyped, and multipoint linkage analysis was conducted using the GENEHUNTER-PLUS and ASM programs. Suggestive evidence of linkage was observed in four regions on three chromosomes (12, 19, and 20). The two largest logarithm of odds scores of 2.63 and 1.92 for chromosomes 20q13.3 and 12q24, respectively, are particularly interesting because these regions have been reported to harbor diabetes susceptibility genes in several other populations and ethnic groups. Given the history of forced migration of West African populations during the slave trade, these results should have considerable relevance to the study of type 2 diabetes in African Americans.

  6. Colonial Legacy, Communist Nostalgia and Failure of Democracy in Sub-Saharan Africa

    DTIC Science & Technology

    2011-03-29

    The slave trade resulted in approximately 11 million West African people being sold by their own leaders to Europeans who exported them across the...in the region‟s development. The exact severity of the slave trade on the West African demographic cannot be quantified due to lack of recorded...a fallacy as earlier indicated above that African leaders did partake actively in the slave trade . These leaders took their followers and sold them

  7. Doppler sounder observations of trade winds and sea breezes along the African west coast near 34 ° S, 19 ° E

    NASA Astrophysics Data System (ADS)

    Jury, Mark; Spencer-Smith, Garth

    1988-09-01

    Summer weather conditions along the west coast of Africa near 34 ° S, 18 ° E are investigated using doppler acoustic sounder profiles. Case studies were selected from a two-year record to form composite analyses over the diurnal cycle. The SE trade wind exhibited a low level jet at the level of the temperature inversion due to a sharp reversal in the thermal wind vector aloft. Mean wind speeds reached 14 m s-1 just before midnight as the surface and upper inversions strengthened. Seabreezes were categorised by the supporting gradient wind and found to have mean depths of 400 m, speeds of over 6 m s-1 at the 200 m level, and advance/retreat times of 09 hr and 16 20 hr. During seabreezes and weak on-shore gradient flow conditions, the thermal internal boundary layer (TIBL) was monitored with sounder transects in the first 12 km of the coastal zone. The growth height was observed to be 1:20 in the first 5 km and 1:50 farther inland. The sounder climatology, together with surface network and aerial survey results, illustrate the four-dimensional characteristics of trade winds and seabreezes near Cape Town.

  8. Concept for a large master/slave-controlled robotic hand

    NASA Technical Reports Server (NTRS)

    Grissom, William A.; Abdallah, Mahmoud A.; White, Carl L.

    1988-01-01

    A strategy is presented for the design and construction of a large master/slave-controlled, five-finger robotic hand. Each of the five fingers will possess four independent axes each driven by a brushless DC servomotor and, thus, four degrees-of-freedom. It is proposed that commercially available components be utilized as much as possible to fabricate a working laboratory model of the device with an anticipated overall length of two-to-four feet (0.6 to 1.2 m). The fingers are to be designed so that proximity, tactile, or force/torque sensors can be imbedded in their structure. In order to provide for the simultaneous control of the twenty independent hand joints, a multilevel master/slave control strategy is proposed in which the operator wears a specially instrumented glove which produces control signals corresponding to the finger configurations and which is capable of conveying sensor feedback signals to the operator. Two dexterous hand master devices are currently commercially available for this application with both undergoing continuing development. A third approach to be investigated for the master control mode is the use of real-time image processing of a specially patterned master glove to provide the respective control signals for positioning the multiple finger joints.

  9. Slave mode expansion for obtaining ab initio interatomic potentials

    NASA Astrophysics Data System (ADS)

    Ai, Xinyuan; Chen, Yue; Marianetti, Chris A.

    2014-07-01

    Here we propose an approach for performing a Taylor series expansion of the first-principles computed energy of a crystal as a function of the nuclear displacements. We enlarge the dimensionality of the existing displacement space and form new variables (i.e., slave modes) which transform like irreducible representations of the point group and satisfy homogeneity of free space. Standard group theoretical techniques can then be applied to deduce the nonzero expansion coefficients a priori. At a given order, the translation group can be used to contract the products and eliminate terms which are not linearly independent, resulting in a final set of slave mode products. While the expansion coefficients can be computed in a variety of ways, we demonstrate that finite difference is effective up to fourth order. We demonstrate the power of the method in the strongly anharmonic system PbTe. All anharmonic terms within an octahedron are computed up to fourth order. A proper unitary transformation demonstrates that the vast majority of the anharmonicity can be attributed to just two terms, indicating that a minimal model of phonon interactions is achievable. The ability to straightforwardly generate polynomial potentials will allow precise simulations at length and time scales which were previously unrealizable.

  10. The topology of African exports: Emerging patterns on spanning trees

    NASA Astrophysics Data System (ADS)

    Araújo, Tanya; Ferreira, Manuel Ennes

    2016-11-01

    This paper is a contribution to interweaving two lines of research that have progressed in separate ways: network analysis of international trade and the literature on African trade and development. Gathering empirical data on African countries has important limitations and so does the space occupied by African countries in the analysis of trade networks. Here, these limitations are dealt with by the definition of two independent bipartite networks: a destination share network and a commodity share network. These networks-together with their corresponding minimal spanning trees-allow to uncover some ordering emerging from African exports in the broader context of international trade. The emerging patterns help to understand important characteristics of African exports and its binding relations to other economic, geographic and organizational concerns as the recent literature on African trade, development and growth has shown.

  11. HTLV type 1 molecular study in Brazilian villages with African characteristics giving support to the post-Columbian introduction hypothesis.

    PubMed

    Rego, Filipe Ferreira de Almeida; Alcantara, Luiz Carlos Junior; Moura Neto, Jose Pereira; Miranda, Aline Cristina Andrade Mota; Pereira, Osmario de Souza; Gonçalves, Marilda de Souza; Galvão-Castro, Bernardo

    2008-05-01

    We performed an HTLV epidemiological study of 986 individuals from 17 villages from the same state of Salvador, the city with the highest HTLV-1 prevalence in Brazil. The HTLV-1 prevalence was 3.85%, 1.56%, and 1.23% in three villages. Phylogenetic analysis of the LTR region demonstrated that all positive samples analyzed belonged to the Transcontinental subgroup of the HTLV-1 Cosmopolitan subtype. Three of the new HTLV-1 sequences formed a well-supported clade within one of the Latin American clusters that contain a South African sequence. This Latin American cluster that segregated from the same ancestor as the other clade contained a Central African sequence. This ancestral relationship could support our previous report that suggests that this subgroup was first introduced into South Africa as a result of the migration of the Bantu population from Central Africa to Southern Africa over the past 3000 years, and afterward to Brazil during the slave trade between the sixteenth and nineteenth centuries.

  12. Sable Queens in Bondage: Reading, Independent Study, and Research on the American Slave Narrative.

    ERIC Educational Resources Information Center

    Denniston, Dorothy L.

    This paper examines the scope and historical significance of biographies and autobiographies of ex-slaves. The document focuses primarily on accounts of black women published from 1820-1860, but also discusses several narratives from colonial times. Exploits of famous women slaves including Harriet Tubman and Sojourner Truth are analyzed along…

  13. Health, Human Capital, and African American Migration Before 1910.

    PubMed

    Logan, Trevon D

    2009-04-01

    Using both IPUMS and the Colored Troops Sample of the Civil War Union Army Data, I estimate the effects of literacy and health on the migration propensities of African Americans from 1870 to 1910. I find that literacy and health shocks were strong predictors of migration and the stock of health was not. There were differential selection propensities based on slave status-former slaves were less likely to migrate given a specific health shock than free blacks. Counterfactuals suggest that as much as 35 percent of the difference in the mobility patterns of former slaves and free blacks is explained by differences in their human capital, and more than 20 percent of that difference is due to health alone. Overall, the selection effect of literacy on migration is reduced by one-tenth to one-third once health is controlled for. The low levels of human capital accumulation and rates of mobility for African Americans after the Civil War are partly explained by the poor health status of slaves and their immediate descendants.

  14. Health, Human Capital, and African American Migration Before 1910

    PubMed Central

    Logan, Trevon D.

    2009-01-01

    Using both IPUMS and the Colored Troops Sample of the Civil War Union Army Data, I estimate the effects of literacy and health on the migration propensities of African Americans from 1870 to 1910. I find that literacy and health shocks were strong predictors of migration and the stock of health was not. There were differential selection propensities based on slave status—former slaves were less likely to migrate given a specific health shock than free blacks. Counterfactuals suggest that as much as 35 percent of the difference in the mobility patterns of former slaves and free blacks is explained by differences in their human capital, and more than 20 percent of that difference is due to health alone. Overall, the selection effect of literacy on migration is reduced by one-tenth to one-third once health is controlled for. The low levels of human capital accumulation and rates of mobility for African Americans after the Civil War are partly explained by the poor health status of slaves and their immediate descendants. PMID:20161107

  15. White Racism and Africanity in the Development of AFro-American Communities.

    ERIC Educational Resources Information Center

    Jones, Ferdinand

    The construction of hypotheses concerning blacks in America requires an understanding of two enduring influences on collective black experience: (1) whites' treatment of blacks as slaves and (2) West African culture that helped to shape black adaptation to the conditions engendered by slavery. White racist attitudes and the psychological distance…

  16. Master-slave robotic system for therapeutic gastrointestinal endoscopic procedures.

    PubMed

    Low, S C; Tang, S W; Thant, Z M; Phee, L; Ho, K Y; Chung, S C

    2006-01-01

    Flexible endoscopy is used to inspect and treat disorders of the gastrointestinal (GI) tract without the need for creating an artificial opening on the patient's body. Simple surgical procedures (like polypectomy and biopsy) can be performed by introducing a flexible tool via a working channel to reach the site of interest at the distal end. More technically demanding surgical procedures like hemostasis for arterial bleeding, or suturing to mend a perforation cannot be effectively achieved with flexible endoscopy. The proposed robotic system enables the endoscopist to perform technically demanding therapeutic procedures (currently possible only with open surgery) in conjunction with conventional flexible endoscopes. The robotic system consists of a master console and a slave. The latter is a cable driven flexible robotic manipulator that can be inserted into tool channel of existing endoscopes or attached in tandem to the endoscopes. Together with the real time endoscopic view, the endoscopist would be capable of performing more intricate and difficult surgical procedures.

  17. Superfluid density in the slave-boson theory

    NASA Astrophysics Data System (ADS)

    Zhong, Yin; Lu, Han-Tao; Luo, Hong-Gang

    2016-02-01

    Despite of the success of the slave-boson theory in capturing qualitative physics of high-temperature superconductors like cuprates, it fails to reproduce the correct temperature-dependent behavior of superfluid density, let alone the independence of the linear temperature term on doping in the underdoped regimes of hole-doped cuprate, a common experimental observation in different cuprates. It remains puzzling up to now in spite of intensive theoretical efforts. For electron-doped case, even qualitative treatment is not reported at present time. Here we revisit these problems and provide an alternative superfluid density formulation by using the London relation instead of employing the paramagnetic current-current correlation function. The obtained formula, on the one hand, provides the correct temperature-dependent behavior of the superfluid density in the whole temperature regime, on the other hand, makes the doping dependence of the linear temperature term substantially weaken and a possible interpretation for its independence on doping is proposed. As an application, electron-doped cuprate is studied, whose result qualitatively agrees with existing experiments and successfully explains the origin of d- to anisotropic s-wave transition across the optimal doping. Our result remedies some failures of the slave-boson theory as employed to calculate superfluid density in cuprates and may be useful in the understanding of the related physics in other strongly correlated systems, e.g. Na x CoO2· yH2O and certain iron-based superconductors with dominating local magnetic exchange interaction.

  18. Control of haptic master - slave robot system for minimally invasive surgery (MIS)

    NASA Astrophysics Data System (ADS)

    Oh, J. S.; Shin, W. K.; Uhm, C. H.; Lee, S. R.; Han, Y. M.; Choi, S. B.

    2013-02-01

    In this work, 4 degrees-of-freedom (DOF) haptic master featuring electrorheological (ER) fluid is proposed and integrated with a slave. Using an ER fluid, the haptic master is devised which can generate a repulsive force/torque with the 4-DOF motion and provide stimulus information to operator. For realization of master-slave MIS system, an encoder is installed with the ER haptic master to establish the MIS master system. The motion command of the haptic master is realized by slave surgery robot. In order to follow the motion of the haptic master, the mechanism of slave surgery robot is devised. Accordingly, the haptic master-slave system is established by incorporating the slave robot with the haptic master device in which the repulsive force/torque and desired position are transferred to each other. In order to obtain the desired torque trajectories, a sliding mode controller (SMC) is designed and implemented. It has been demonstrated that the desired effective torque tracking control performance is well achieved using the proposed master-slave system.

  19. Tracing ancestor rice of Suriname Maroons back to its African origin.

    PubMed

    van Andel, Tinde R; Meyer, Rachel S; Aflitos, Saulo A; Carney, Judith A; Veltman, Margaretha A; Copetti, Dario; Flowers, Jonathan M; Havinga, Reinout M; Maat, Harro; Purugganan, Michael D; Wing, Rod A; Schranz, M Eric

    2016-10-03

    African rice (Oryza glaberrima) and African cultivation practices are said to have influenced emerging colonial plantation economies in the Americas(1,2). However, the level of impact of African rice practices is difficult to establish because of limited written or botanical records(2,3). Recent findings of O. glaberrima in rice fields of Suriname Maroons bear evidence of the high level of knowledge about rice among African slaves and their descendants, who consecrate it in ancestor rituals(4,5). Here we establish the strong similarity, and hence likely origin, of the first extant New World landrace of O. glaberrima to landraces from the Upper Guinean forests in West Africa. We collected African rice from a Maroon market in Paramaribo, Suriname, propagated it, sequenced its genome(6) and compared it with genomes of 109 accessions representing O. glaberrima diversity across West Africa. By analysing 1,649,769 single nucleotide polymorphisms (SNPs) in clustering analyses, the Suriname sample appears sister to an Ivory Coast landrace, and shows no evidence of introgression from Asian rice. Whereas the Dutch took most slaves from Ghana, Benin and Central Africa(7), the diaries of slave ship captains record the purchase of food for provisions when sailing along the West African Coast(8), offering one possible explanation for the patterns of genetic similarity. This study demonstrates the utility of genomics in understanding the largely unwritten histories of crop cultures of diaspora communities.

  20. The design and implementation of MPI master-slave parallel genetic algorithm

    NASA Astrophysics Data System (ADS)

    Liu, Shuping; Cheng, Yanliu

    2013-03-01

    In this paper, the MPI master-slave parallel genetic algorithm is implemented by analyzing the basic genetic algorithm and parallel MPI program, and building a Linux cluster. This algorithm is used for the test of maximum value problems (Rosen brocks function) .And we acquire the factors influencing the master-slave parallel genetic algorithm by deriving from the analysis of test data. The experimental data shows that the balanced hardware configuration and software design optimization can improve the performance of system in the complexity of the computing environment using the master-slave parallel genetic algorithms.

  1. Finite-time master-slave synchronization and parameter identification for uncertain Lurie systems.

    PubMed

    Wang, Tianbo; Zhao, Shouwei; Zhou, Wuneng; Yu, Weiqin

    2014-07-01

    This paper investigates the finite-time master-slave synchronization and parameter identification problem for uncertain Lurie systems based on the finite-time stability theory and the adaptive control method. The finite-time master-slave synchronization means that the state of a slave system follows with that of a master system in finite time, which is more reasonable than the asymptotical synchronization in applications. The uncertainties include the unknown parameters and noise disturbances. An adaptive controller and update laws which ensures the synchronization and parameter identification to be realized in finite time are constructed. Finally, two numerical examples are given to show the effectiveness of the proposed method.

  2. Robust master-slave synchronization for general uncertain delayed dynamical model based on adaptive control scheme.

    PubMed

    Wang, Tianbo; Zhou, Wuneng; Zhao, Shouwei; Yu, Weiqin

    2014-03-01

    In this paper, the robust exponential synchronization problem for a class of uncertain delayed master-slave dynamical system is investigated by using the adaptive control method. Different from some existing master-slave models, the considered master-slave system includes bounded unmodeled dynamics. In order to compensate the effect of unmodeled dynamics and effectively achieve synchronization, a novel adaptive controller with simple updated laws is proposed. Moreover, the results are given in terms of LMIs, which can be easily solved by LMI Toolbox in Matlab. A numerical example is given to illustrate the effectiveness of the method.

  3. Updating the African human mitochondrial DNA tree: Relevance to forensic and population genetics.

    PubMed

    Heinz, Tanja; Pala, Maria; Gómez-Carballa, Alberto; Richards, Martin B; Salas, Antonio

    2017-03-01

    Analysis of human mitochondrial DNA (mtDNA) variation plays an important role in forensic genetic investigations, especially in degraded biological samples and hair shafts. There are many issues of the mtDNA phylogeny that are of special interest to the forensic community, such as haplogroup classification or the post hoc investigation of potential errors in mtDNA datasets. We have analyzed >2200 mitogenomes of African ancestry with the aim of improving the known worldwide phylogeny. More than 300 new minor subclades were identified, and the Time to the Most Recent Common Ancestor (TMRCA) was estimated for each node of the phylogeny. Phylogeographic details are provided which might also be relevant to forensic genetics. The present study has special interest for forensic investigations because current analysis and interpretation of mtDNA casework rest on a solid worldwide phylogeny, as is evident from the role that phylogeny plays in popular resources in the field (e.g. PhyloTree), software (e.g. Haplogrep 2), and databases (e.g. EMPOP). Apart from this forensic genetic interest, we also highlight the impact of this research in anthropological studies, such as those related to the reconstruction of the transatlantic slave trade.

  4. Master-Slave optical coherence tomography for parallel processing, calibration free and dispersion tolerance operation

    NASA Astrophysics Data System (ADS)

    Bradu, Adrian; Kapinchev, Konstantin; Barnes, Fred; Podoleanu, Adrian G.

    2015-03-01

    We present further improvements on the Master Slave (MS) interferometry method since our first communication [1]. In this paper, we present more data collection and additionally demonstrate an important feature of the MS method, that of tolerance to dispersion. MS interferometry produces the interference of a selected point in depth based on principles of spectral domain (SD) interferometry, but without the need of a Fast Fourier transformation (FFT). The method can be used to directly produce en-face optical coherence tomography (OCT) images but also as a tool to accurately measure distances in low coherence interferometry for sensing applications [1]. In the MS-OCT method, cross-correlation is applied to both methods of SD-OCT, spectrometer based (SP) or swept source (SS) OCT. The channelled spectrum provided by an OCT system is correlated with the signal produced by reading a stored mask. Several such masks can be used simultaneously. The masks operate as adaptive filters. Each mask (filter) determines recognition in the measured channelled spectrum delivered by the interferometer, of the pattern corresponding to each optical path difference to be recognized. The method presents net advantages in comparison with the classical method of producing axial reflectivity profiles by FFT: no need for resampling of data, possibility to tailor the trade-off between depth resolution and sensitivity. Here, using a swept source, the MS method is used to obtain axial reflectivity profiles, which are compared to the axial profiles obtained by calibration of data and FFT. The tolerance to dispersion of the MS method was assumed in [1] but not demonstrated. Here, measurements are performed to demonstrate its axial resolution independence on dispersion.

  5. Modified Streamflows 1990 Level of Irrigation : Missouri, Colorado, Peace and Slave River Basin, 1928-1989.

    SciTech Connect

    A.G. Crook Company; United States. Bonneville Power Administration

    1993-07-01

    This report presents data for monthly mean streamflows adjusted for storage change, evaporation, and irrigation, for the years 1928-1990, for the Colorado River Basin, the Missouri River Basin, the Peace River Basin, and the Slave River Basin.

  6. Slave finite elements for nonlinear analysis of engine structures, volume 1

    NASA Technical Reports Server (NTRS)

    Gellin, S.

    1991-01-01

    A 336 degrees of freedom slave finite element processing capability to analyze engine structures under severe thermomechanical loading is presented. Description of the theoretical development and demonstration of that element is presented in this volume.

  7. Heat, sex, and sugar: pregnancy and childbearing in the slave quarters.

    PubMed

    Follett, Richard

    2004-10-01

    This article examines the dynamics of slave fecundity in the antebellum South and analyzes the relationship between the planters' labor requirements and pregnancy on large sugar estates in nineteenth-century Louisiana. In contrast to the cotton states, where the slave population grew, bondspeople in Louisiana's sugar world experienced natural population decrease. This derived in part from imbalanced sex ratios, but as this article explores, it also occurred because of the punishing nature of sugar production that taxed slave women in distinct ways over the entire year. As this article shows, conceptions peaked during the annual harvest season but collapsed at other times because of nutritional stress, overwork, heat, and exhaustion. Addressing the seasonality of slave childbirths, the article posits that workload combined with climatic, ecological, hormonal, nutritional, and lactation factors ultimately shaped the reproductive ecology of American slavery.

  8. Physics and Slavery: The Relative Cost of Calories for Slave Infants and Their Mothers,

    DTIC Science & Technology

    1979-11-01

    THE RELATIVE COST OF CALORIES FOR SLAVE INFANTS AND THEIR MOTHERSI In Time On The Cross Robert Fogel and Stanley Engerman use as the rate of slave...was supported by National Science Foundation Grants GS-3262 and GS-27262 to Harvard University. 2Robert William Fogel and Stanley L. Engerman, Time On...is an exemplary practice in this regard. Since the methods employed by Fogel and Engerman give more weight to children than to adults, their value

  9. Bilateral force reflection for teleoperators with masters and slaves with dissimilar and possibly redundant kinematics

    SciTech Connect

    Jansen, J.F.; Babcock, S.M.

    1989-11-01

    Several bilateral control techniques and methods for exploiting redundant slaves are investigated as a part of research to develop and analyze bilateral, force-reflecting control methodologies for teleoperator systems with kinematic dissimilar masters and slaves. The study indicates that, with force/torque sensing at the wrist, and an impedance type of controller with the appropriate joint compensation, a significant improvement in performance and controllability of a teleoperator system can be achieved. 32 refs., 6 figs., 2 tabs.

  10. Autonomous avoidance based on motion delay of master-slave surgical robot.

    PubMed

    Inoue, Shintaro; Toyoda, Kazutaka; Kobayashi, Yo; Fujie, Masakatsu G

    2009-01-01

    Safe use of master-slave robots for endoscopic surgery requires autonomous motions to avert contact with vital organs, blood vessels, and nerves. Here we describe an avoidance control algorithm with delay compensation that takes the dynamic characteristics of the robot into account. To determine the operating parameters, we measured frequency characteristics of each joint of the slave-manipulator. The results suggest this delay compensation program improves avoidance performance.

  11. Master-slave system with force feedback based on dynamics of virtual model

    NASA Technical Reports Server (NTRS)

    Nojima, Shuji; Hashimoto, Hideki

    1994-01-01

    A master-slave system can extend manipulating and sensing capabilities of a human operator to a remote environment. But the master-slave system has two serious problems: one is the mechanically large impedance of the system; the other is the mechanical complexity of the slave for complex remote tasks. These two problems reduce the efficiency of the system. If the slave has local intelligence, it can help the human operator by using its good points like fast calculation and large memory. The authors suggest that the slave is a dextrous hand with many degrees of freedom able to manipulate an object of known shape. It is further suggested that the dimensions of the remote work space be shared by the human operator and the slave. The effect of the large impedance of the system can be reduced in a virtual model, a physical model constructed in a computer with physical parameters as if it were in the real world. A method to determine the damping parameter dynamically for the virtual model is proposed. Experimental results show that this virtual model is better than the virtual model with fixed damping.

  12. Software architecture for a kinematically dissimilar master-slave telethesis for exploring rehabilitation applications

    NASA Astrophysics Data System (ADS)

    Wunderlich, Joseph; Chen, Shoupu; Pino, D.; Rahman, Tariq; Harwin, William S.

    1993-12-01

    A person with limited arm and hand function could benefit from technology based on teleoperation principles, particularly where the mechanism provides proprioceptive-like information to the operator giving an idea of the forces encountered in the environment and the positions of the slave robot. A test-bed system is being prepared to evaluate the potential for adapting telemanipulator technology to the needs of people with high level spinal cord injury. This test-bed uses a kinematically dissimilar master and slave pair and will be adaptable to a variety of disabilities. The master will be head controlled and when combined with auxiliary functions will provide the degrees of freedom necessary to attempt any task. In the simplest case, this mapping could be direct, with the slave amplifying the person's movements and forces. It is unrealistic however to expect that the operator will have the range of head movement required for accurate operation of the slave over the full workspace. Neither is it likely that the person will be able to achieve simultaneous and independent control of the 6 or more degrees of freedom required to move the slave. Thus a set of more general mappings must be available that can be chosen to relate to the intrinsic coordinates of the task. The software structure to implement the control of this master-slave system is based on two IBM PC computers linked via an ethernet.

  13. Telerobot tool maintenance using master-slave manipulators

    SciTech Connect

    Kriikku, E.M.

    1992-08-20

    The Savannah River Site (SRS) will process large bulky transuranic (TRU) waste items with a robotic gantry manipulator. The Savannah River Technology Center (SRTC) built a TRU Waste Test Facility (TWTF) to demonstrate this concept. The test robot uses several tools (i.e. plasma torch, chain saw, and gripper) to open, size reduce, and repackage simulated waste items. Waste processing campaigns in the TWTF show the various robot tools require periodic maintenance, such as replacing the torch tip and replacing saw blades. The primary objectives of this test were to determine if standard master-slave manipulators (MSMS) can complete remote robot tool maintenance, and if so, how long does the maintenance take. Test results show that MSMs completed 5 of 8 tool maintenance tasks attempted, and each task took 15 minutes or less. The three tasks that couldn't be completed involved specially designed tools, and these tools could be redesigned to allow remote MSM maintenance. MSMs can complete robot tool maintenance in a reasonable amount of time. This conclusion supports the SRS philosophy of remotely processing large bulky TRU waste items using a robotic gantry manipulator.

  14. Telerobot tool maintenance using master-slave manipulators

    SciTech Connect

    Kriikku, E.M.

    1992-08-20

    The Savannah River Site (SRS) will process large bulky transuranic (TRU) waste items with a robotic gantry manipulator. The Savannah River Technology Center (SRTC) built a TRU Waste Test Facility (TWTF) to demonstrate this concept. The test robot uses several tools (i.e. plasma torch, chain saw, and gripper) to open, size reduce, and repackage simulated waste items. Waste processing campaigns in the TWTF show the various robot tools require periodic maintenance, such as replacing the torch tip and replacing saw blades. The primary objectives of this test were to determine if standard master-slave manipulators (MSMS) can complete remote robot tool maintenance, and if so, how long does the maintenance take. Test results show that MSMs completed 5 of 8 tool maintenance tasks attempted, and each task took 15 minutes or less. The three tasks that couldn`t be completed involved specially designed tools, and these tools could be redesigned to allow remote MSM maintenance. MSMs can complete robot tool maintenance in a reasonable amount of time. This conclusion supports the SRS philosophy of remotely processing large bulky TRU waste items using a robotic gantry manipulator.

  15. Lithopsheric anisotropy in the Archean Slave craton, Canada

    NASA Astrophysics Data System (ADS)

    Snyder, D. B.; Bostock, M.; Lockhart, G. D.

    2003-12-01

    Shear wave anisotropy and discontinuity studies of teleseismic earthquakes recorded at single seismic stations help to define vertical mantle stratigraphic columns. Beneath the Archean outcrops of the central Slave craton seismic discontinuities at 38, 115, 140, and 190 km appear to bound two distinct anisotropic layers. The discontinuity at 38 km is the Moho; discontinuities at 110-120 and 140-150 km depths observed at multiple nearby stations indicate that a layer of low velocity or distinct anisotropy exists between these depths. The coherent pulses at about 13 seconds on the radial component indicates a strong decrease in velocity at 110 km depth north and west of the Ekati diamond mine, but not to the south. The response on the transverse component indicates a rotation of anisotropic fabric at 117 km depth, a reversal at 140 km, and another rotation at 190 km. A flip in polarity at a back azimuth of about 280° occurs in the 117 km discontinuity and apparently marks an axis of symmetry of anisotropy, here probably the dip direction of steep layering or planar fabric. SKS anisotropy studies at this station indicate that the upper of two anisotopic layers has a fast-axis direction of 010° . Geochemical studies of xenolith samples from nearby kimberlites suggest that the boundaries at 115 and 140 bound a layer of ultra-depleted harzburgite, almost pure olivine, that formed as oceanic crust.

  16. Slave rotor approach to dynamically screened Coulomb interactions in solids

    NASA Astrophysics Data System (ADS)

    Krivenko, I. S.; Biermann, S.

    2015-04-01

    Recent studies of dynamical screening of the electronic Coulomb interactions in solids have revived interest in lattice models of correlated fermions coupled to bosonic degrees of freedom (Hubbard-Holstein-type models). We propose a new dynamical mean-field-based approach to dynamically screened Coulomb interactions. In the effective Anderson-Holstein model, a transformation to slave rotors [S. Florens and A. Georges, Phys. Rev. B 66, 165111 (2002), 10.1103/PhysRevB.66.165111] is performed to decouple the dynamical part of the interaction. This transformation allows for a systematic derivation and analysis of recently introduced approximate schemes for the solution of dynamical impurity problems, in particular, the Bose factor ansatz within the dynamic atomic limit approximation (DALA) with and without Lang-Firsov correction. More importantly still, it suggests an optimized choice for a Bose factor in the sense of the variational principle of Feynman and Peierls. We demonstrate the accuracy of our scheme and present a comparison to calculations within the DALA.

  17. Master slave en-face OCT/SLO.

    PubMed

    Bradu, Adrian; Kapinchev, Konstantin; Barnes, Frederick; Podoleanu, Adrian

    2015-09-01

    Master Slave optical coherence tomography (MS-OCT) is an OCT method that does not require resampling of data and can be used to deliver en-face images from several depths simultaneously. As the MS-OCT method requires important computational resources, the number of multiple depth en-face images that can be produced in real-time is limited. Here, we demonstrate progress in taking advantage of the parallel processing feature of the MS-OCT technology. Harnessing the capabilities of graphics processing units (GPU)s, information from 384 depth positions is acquired in one raster with real time display of up to 40 en-face OCT images. These exhibit comparable resolution and sensitivity to the images produced using the conventional Fourier domain based method. The GPU facilitates versatile real time selection of parameters, such as the depth positions of the 40 images out of the set of 384 depth locations, as well as their axial resolution. In each updated displayed frame, in parallel with the 40 en-face OCT images, a scanning laser ophthalmoscopy (SLO) lookalike image is presented together with two B-scan OCT images oriented along rectangular directions. The thickness of the SLO lookalike image is dynamically determined by the choice of number of en-face OCT images displayed in the frame and the choice of differential axial distance between them.

  18. The Underground Railroad: Developing a Literary Track to Slave Narrative.

    ERIC Educational Resources Information Center

    Goncalves, Wande Knox

    This paper offers a method of bringing to third-grade students an understanding of African-American contributions to the United States, the experience of slavery, and the struggle for freedom on the secretive Underground Railroad. The paper contains a list of eight primary sources to be used. Its lessons focus specifically on the skills necessary…

  19. Supercontinents, True Polar Wander, and Paleogeography of the Slave Craton

    NASA Astrophysics Data System (ADS)

    Mitchell, Ross Nelson

    evidence in support of a long-lived, Ediacaran-aged hotspot. The consistency of paleocurrent directions derived from the Great Slave Supergroup argues against significant regional vertical-axis rotations and for large and rapid TPW to explain discordant paleomagnetic directions observed within section. The last frontier for paleomagnetic constraints on supercontinents, TPW, and the antiquity of plate tectonics is earliest Proterozoic time. Laurentia, one of Earth's oldest continents that formed at the core supercontinent Nuna, contains several cratons that have adequate paleomagnetic and geochronologic data with which to test for evidence of early TPW and relative plate motion, the hallmark of tectonics. Although past comparisons have been made between the Slave and Superior cratons at each "bookend" of Laurentia, new paleomagnetic data supported by baked contact tests allow for conclusive early Proterozoic reconstructions. Similar to periods following Proterozoic supercontinents Nuna and Rodinia, early Proterozoic time is characterized by large TPW oscillations and large-scale plate reorganizations prior to amalgamation, possibly indicating the presence of `Kenorland', an Archean supercontinent.

  20. Remote telerobotic replacement for master-slave manipulator

    SciTech Connect

    Heckendorn, F.M.; Iverson, D.C.; LaValle, D.R.

    1997-05-01

    A remotely replaceable telerobotic manipulator (TRM) has been developed and deployed at the Defense Waste Processing Facility (DWPF) in support of its radioactive operation. The TRM replaces a Master-Slave Manipulator (MSM). The TRM is in use for both routine and recovery operations for the radioactive waste vitrification melter, the primary production device within the DWPF. The arm was designed for deployment and operation using an existing MSM penetration. This replacement of an existing MSM with a high power robotic device demonstrates the capability to perform similar replacement in other operating facilities. The MSM`s were originally deployed in the DWPF to perform routine light capacity tasks. During the testing phase of the DWPF, prior to its radioactive startup in 5/96, the need to remove glass deposits that can form at the melter discharge during filling of glass containment canisters was identified. The combination of high radiation and contamination in the DWPF melter cell during radioactive operation eliminated personnel entry as a recovery option. Therefore remote cleaning methods had to be devised. The MSM`s had neither the reach nor the strength required for this task. It became apparent that a robust manipulator arm would be required for recovery from these potential melter discharge pluggage events. The existing wall penetrations, used for the MSM`s, could not be altered for seismic and radiological reasons. The new manipulator was required to be of considerable reach, due to existing physical layout, and strength, due to the glass removal requirement. Additionally, the device would have to compatible with high radiation and remote crane installation. The physical size of the manipulator and the weight of components must be consistent with the existing facilities. It was recognized early-on that a manipulator of sufficient strength to recover from a pluggage event would require robotic functions to constrain undesirable motions.

  1. Spatial distribution of eclogite in the Slave cratonic mantle: The role of subduction

    NASA Astrophysics Data System (ADS)

    Kopylova, Maya G.; Beausoleil, Yvette; Goncharov, Alexey; Burgess, Jennifer; Strand, Pamela

    2016-03-01

    We reconstructed the spatial distribution of eclogites in the cratonic mantle based on thermobarometry for ~ 240 xenoliths in 4 kimberlite pipes from different parts of the Slave craton (Canada). The accuracy of depth estimates is ensured by the use of a recently calibrated thermometer, projection of temperatures onto well-constrained local peridotitic geotherms, petrological screening for unrealistic temperature estimates, and internal consistency of all data. The depth estimates are based on new data on mineral chemistry and petrography of 148 eclogite xenoliths from the Jericho and Muskox kimberlites of the northern Slave craton and previously reported analyses of 95 eclogites from Diavik and Ekati kimberlites (Central Slave). The majority of Northern Slave eclogites of the crustal, subduction origin occurs at 110-170 km, shallower than in the majority of the Central Slave crustal eclogites (120-210 km). The identical geochronological history of these eclogite populations and the absence of steep suture boundaries between the central and northern Slave craton suggest the lateral continuity of the mantle layer relatively rich in eclogites. We explain the distribution of eclogites by partial preservation of an imbricated and plastically dispersed oceanic slab formed by easterly dipping Proterozoic subduction. The depths of eclogite localization do not correlate with geophysically mapped discontinuities. The base of the depleted lithosphere of the Slave craton constrained by thermobarometry of peridotite xenoliths coincides with the base of the thickened lithospheric slab, which supports contribution of the recycled oceanic lithosphere to formation of the cratonic root. Its architecture may have been protected by circum-cratonic subduction and shielding of the shallow Archean lithosphere from the destructive asthenospheric metasomatism.

  2. Turbo Pascal Implementation of a Distributed Processing Network of MS-DOS Microcomputers Connected in a Master-Slave Configuration

    DTIC Science & Technology

    1989-12-01

    pressing a local key which aborts the Slave program. D. DESIGN CONSIDERATIONS 1. Assembly Language Assembly language is used in only two locations in this...prepare for the next command. The program is aborted and control is returned to the operating system if any key on the Slave keyboard is depressed. No...screen. The program is aborted and control is returned to the operating system if any key on the Slave keyboard is depressed. No warning is sent to the

  3. The Art of Ore: Chinese Strategy in Africa

    DTIC Science & Technology

    2010-06-01

    advent of the slave trade , the British, French, Spanish, and Dutch rapidly increased their African engagement, building trading forts or...initiated trade relationships along the coastline cities of Africa. For about two centuries it dominated trade along the West African coast. With the...a lost empire. US Relationship Outside of the trans-Atlantic slave trade , the United States has historically invested comparatively little in

  4. Design and control of MR haptic master/slave robot system for minimally invasive surgery

    NASA Astrophysics Data System (ADS)

    Uhm, Chang-Ho; Nguyen, Phoung Bac; Choi, Seung-Bok

    2013-04-01

    In this work, magnetorheological (MR) haptic master and slave robot for minimally invasive surgery (MIS) have been designed and tested. The proposed haptic master consists of four actuators; three MR brakes featuring gimbal structure for 3-DOF rotation motion(X, Y and Z axes) and one MR linear actuator for 1-DOF translational motion. The proposed slave robot which is connected with the haptic master has vertically multi- joints, and it consists of four DC servomotors; three for positioning endoscope and one for spinning motion. We added a fixed bar with a ball joint on the base of the slave for the endoscope position at the patient's abdomen to maintain safety. A gimbal structure at the end of the slave robotic arm for the last joint rotates freely with respect to the pivot point of the fixed bar. This master-slave system runs as if a teleoperation system through TCP/IP connection, programmed by LabVIEW. In order to achieve the desired position trajectory, a proportional-integral-derivative (PID) controller is designed and implemented. It has been demonstrated that the effective tracking control performances for the desired motion are well achieved and presented in time domain. At last, an experiment in virtual environments is undertaken to investigate the effectiveness of the MR haptic master device for MIS system.

  5. Power-combining based on master-slave injection-locking magnetron

    NASA Astrophysics Data System (ADS)

    Ping, Yuan; Yi, Zhang; Wenjun, Ye; Huacheng, Zhu; Kama, Huang; Yang, Yang

    2016-07-01

    A microwave power-combining system composed of two Panasonic 2M244-M1 magnetrons based on master-slave injection-locking is demonstrated in this paper. The principle of master-slave injection-locking and the locking condition are theoretical analyzed. Experimental results are consistent with the theoretical analysis and the experimental combined efficiency is higher than 96%. Compared with the external-injection-locked system, the power-combining based on the master-slave injection-locking magnetron is superior by taking out the external solid-state driver and the real-time phase control system. Thus, this power-combining system has great potential for obtaining a high efficiency, high stability, low cost, and high power microwave source. Project supported by the National Basic Research Program of China (Grant No. 2013CB328902) and the National Natural Science Foundation of China (Grant No. 61501311).

  6. Super persistent transient in a master-slave configuration with Colpitts oscillators

    NASA Astrophysics Data System (ADS)

    Bonetti, R. C.; de Souza, S. L. T.; Batista, A. M.; Szezech, J. D., Jr.; Caldas, I. L.; Viana, R. L.; Lopes, S. R.; Baptista, M. S.

    2014-10-01

    Master-slave systems have been intensively investigated for modelling the application of chaos in communications. We considered Colpitts oscillators coupled according to a master-slave configuration in order to study chaos synchronization. We revealed the existence of superpersistent transients in this coupled system. The transient is a ubiquitous phenomenon in nonlinear dynamical systems, and it is responsible for important physical phenomena. We characterized superpersistent transients through a scaling law for their average lifetime. Unstable-unstable pair bifurcation has been identified as the generic mechanism for these transients. Moreover, we showed that an additive noise, added to the slave system, may suppress the chaos synchronization. Our results show that synchronization can be achieved for higher coupling strength when there is noise. However, the noise may induce a longer transient if the synchronization is not suppressed.

  7. Black in White America: Historical Perspectives. The African Experience: Exploring What was Lost to a Man Enslaved and Brought to the New World.

    ERIC Educational Resources Information Center

    Dollase, Richard; And Others

    This volume is the first of a three-part course of study for secondary students. The entire course is designed to take six to eight weeks. This unit is concerned with life as Africans knew it in their homeland, before the incursions of the slave traders. While the introductory section describes the traumatic process of being uprooted and enslaved,…

  8. Building Trades.

    ERIC Educational Resources Information Center

    Gudzak, Raymond

    This curriculum guide provides materials for a competency-based course in building trades at the secondary level. The curriculum design uses the curriculum infused model for the teaching of basic skills as part of vocational education and demonstrates the relationship of vocationally related skills to communication, mathematics, and science…

  9. Marine Trades.

    ERIC Educational Resources Information Center

    Abbott, Alan

    This curriculum guide provides materials for a competency-based course in marine trades at the secondary level. The curriculum design uses the curriculum infused model for the teaching of basic skills as part of vocational education and demonstrates the relationship of vocationally related skills to communication, mathematics, and science…

  10. From Master-Slave to Peer-to-Peer Coupling in Chemical Reaction Networks.

    PubMed

    Holló, Gábor; Dúzs, Brigitta; Szalai, Istvan; Lagzi, Istvan

    2017-04-11

    Design strategy through linking a driving pH oscillator (master system) to a pH sensitive complexation, precipitation or protonation equilibrium (slave slave) has been widely used to create and control concentration oscillations of chemical entities (e.g., monovalent cations, DNA, nanoparticles) not participating in the pH oscillatory system. No systematic investigation has been carried out on how the components of these equilibria affect the characteristics of the driving pH oscillators, and this feedback effect has been often neglected in previous studies. Here we show that pH sensitive species (hydrogen carbonate, EDTA) through a pH dependent equilibrium could significantly affect the characteristics (time period and amplitude) of the driving pH oscillators. By varying the concentration of those species we are able to control the strength of the chemical feedback from slave system to master system thus introducing a transition from master-slave coupling to peer-to-peer coupling in linked chemical systems. To illustrate this transition and coupling strategies we investigate two coupled chemical systems, namely the bromate-sulfite pH oscillator and carbonate - carbon dioxide equilibrium and the hydrogen-peroxide-thiosulfate-copper(II) and EDTA complexation equilibrium. As a sign of the peer-to-peer coupling the characteristics of the driving oscillatory systems can be tuned by controlling the feedback strength and the oscillations can be canceled above a critical value of this parameter.

  11. The Antislavery Movement in Early America: Religion, Social Environment and Slave Manumissions

    ERIC Educational Resources Information Center

    Budros, Art

    2005-01-01

    Although traditional explanations of the historic slave manumission movement during the early Republic have stressed religion, rival ones have emphasized broader environmental forces. However, the literature has offered non-systematic conceptualizations of religion and impressionistic empirical analyses of the facilitators of liberations. In…

  12. Simultaneous master-slave Omega pairs. [navigation system featuring low cost receiver

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1974-01-01

    Master-slave sequence ordering of the Omega system is suggested as a method of improving the pair geometry for low-cost receiver user benefit. The sequence change will not affect present sophisticated processor users other than require new labels for some pair combinations, but may require worldwide transmitter operators to slightly alter their long-range synchronizing techniques.

  13. Secondary Education and Emancipation: Secondary Schools for Freed Slaves in the American South, 1862-1875

    ERIC Educational Resources Information Center

    Butchart, Ronald E.; Rolleri, Amy F.

    2004-01-01

    Slavery in the United States denied education to the enslaved. Yet within fifteen years of the beginning of the American Civil War and the freeing of four million American slaves, the freed people and their supporters elaborated a full system of universal education in the South, including over 120 secondary and higher institutions. Historians have…

  14. Mating behaviour in a slave-making ant, Rossomyrmex minuchae (Hymenoptera, Formicidae)

    NASA Astrophysics Data System (ADS)

    Ruano, Francisca; Tinaut, Alberto

    2005-07-01

    The mating behaviour of the ant Rossomyrmex minuchae, a rare, protected slave-making species in Spain, seems to be significantly affected by its particular life history and patchy habitat. The mating behaviour of the entire genus Rossomyrmex is virtually unknown. We present here the results of a 3-year study of mating behaviour in R. minuchae.

  15. Of Broken Bonds and Bondage: An Analysis of Loss in the Slave Narrative Collection

    ERIC Educational Resources Information Center

    Laurie, Anna; Neimeyer, Robert A.

    2010-01-01

    Relatively few scholars have made use of the Slave Narrative Collection, a collection of more than 2,300 autobiographical narratives detailing the lives of people who had been born into slavery. Housed at the Library of Congress, the Collection was gathered during the 1930s under the direction of the Federal Writers Project. Research derived from…

  16. Interior view, Slave Quarter/Service Wing, first floor, east end, perspective ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, Slave Quarter/Service Wing, first floor, east end, perspective view of the east chimney looking northwest (note ghost of mantel, nailing block - Decatur House, National Trust for Historic Preservation, 748 Jackson Place Northwest, Washington, District of Columbia, DC

  17. Interior view, Slave Quarter/Service, second floor, detail view of framing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, Slave Quarter/Service, second floor, detail view of framing to show joists (with ghosts of lathe) and header (trimmer) with keyed through tenon. - Decatur House, National Trust for Historic Preservation, 748 Jackson Place Northwest, Washington, District of Columbia, DC

  18. HOT CELL BUILDING, TRA632. INSTRUMENT FITTINGS, MASTER/SLAVE MANIPULATOR, "POT LID ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HOT CELL BUILDING, TRA-632. INSTRUMENT FITTINGS, MASTER/SLAVE MANIPULATOR, "POT LID CRANE." IDAHO OPERATIONS OFFICE MTR-632-IDO-16, 11/1952. INL INDEX NO. 531-0632-40-396-110574, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  19. An assembly-type master-slave catheter and guidewire driving system for vascular intervention.

    PubMed

    Cha, Hyo-Jeong; Yi, Byung-Ju; Won, Jong Yun

    2017-01-01

    Current vascular intervention inevitably exposes a large amount of X-ray to both an operator and a patient during the procedure. The purpose of this study is to propose a new catheter driving system which assists the operator in aspects of less X-ray exposure and convenient user interface. For this, an assembly-type 4-degree-of-freedom master-slave system was designed and tested to verify the efficiency. First, current vascular intervention procedures are analyzed to develop a new robotic procedure that enables us to use conventional vascular intervention devices such as catheter and guidewire which are commercially available in the market. Some parts of the slave robot which contact the devices were designed to be easily assembled and dissembled from the main body of the slave robot for sterilization. A master robot is compactly designed to conduct insertion and rotational motion and is able to switch from the guidewire driving mode to the catheter driving mode or vice versa. A phantom resembling the human arteries was developed, and the master-slave robotic system is tested using the phantom. The contact force of the guidewire tip according to the shape of the arteries is measured and reflected to the user through the master robot during the phantom experiment. This system can drastically reduce radiation exposure by replacing human effort by a robotic system for high radiation exposure procedures. Also, benefits of the proposed robot system are low cost by employing currently available devices and easy human interface.

  20. Frequency and origins of hemoglobin S mutation in African-derived Brazilian populations.

    PubMed

    De Mello Auricchio, Maria Teresa Balester; Vicente, João Pedro; Meyer, Diogo; Mingroni-Netto, Regina Célia

    2007-12-01

    Africans arrived in Brazil as slaves in great numbers, mainly after 1550. Before the abolition of slavery in Brazil in 1888, many communities, called quilombos, were formed by runaway or abandoned African slaves. These communities are presently referred to as remnants of quilombos, and many are still partially genetically isolated. These remnants can be regarded as relicts of the original African genetic contribution to the Brazilian population. In this study we assessed frequencies and probable geographic origins of hemoglobin S (HBB*S) mutations in remnants of quilombo populations in the Ribeira River valley, São Paulo, Brazil, to reconstruct the history of African-derived populations in the region. We screened for HBB*S mutations in 11 quilombo populations (1,058 samples) and found HBB*S carrier frequencies that ranged from 0% to 14%. We analyzed beta-globin gene cluster haplotypes linked to the HBB*S mutation in 86 chromosomes and found the four known African haplotypes: 70 (81.4%) Bantu (Central Africa Republic), 7 (8.1%) Benin, 7 (8.1%) Senegal, and 2 (2.3%) Cameroon haplotypes. One sickle cell homozygote was Bantu/Bantu and two homozygotes had Bantu/Benin combinations. The high frequency of the sickle cell trait and the diversity of HBB*S linked haplotypes indicate that Brazilian remnants of quilombos are interesting repositories of genetic diversity present in the ancestral African populations.

  1. Design and Implementation of a Compact Master-Slave Robotic System with Force Feedback and Energy Recycling

    NASA Astrophysics Data System (ADS)

    Li, Chunguang; Inoue, Yoshio; Liu, Tao; Shibata, Kyoko; Oka, Koichi

    Master-slave control is becoming increasingly popular in the development of robotic systems which can provide rehabilitation training for hemiplegic patients with a unilaterally disabled limb. However, the system structures and control strategies of existent master-slave systems are always complex. An innovative master-slave system implementing force feedback and motion tracking for a rehabilitation robot is presented in this paper. The system consists of two identical motors with a wired connection, and the two motors are located at the master and slave manipulator sites respectively. The slave motor tracks the motion of the master motor directly driven by a patient. As well, the interaction force produced at the slave site is fed back to the patient. Therefore, the impaired limb driven by the slave motor can imitate the motion of the healthy limb controlling the master motor, and the patient can regulate the control force of the healthy limb properly according to the force sensation. The force sensing and motion tracking are achieved simultaneously with neither force sensors nor sophisticated control algorithms. The system is characterized by simple structure, bidirectional controllability, energy recycling, and force feedback without a force sensor. Test experiments on a prototype were conducted, and the results appraise the advantages of the system and demonstrate the feasibility of the proposed control scheme for a rehabilitation robot.

  2. U.S. Strategy, African Key Actors, and China

    DTIC Science & Technology

    2009-02-20

    national security interests and offer a strategy to counter China’s neocolonial encroachment on the continent. 15. SUBJECT TERMS African Political Elites...offer a strategy to counter China’s neocolonial encroachment on the continent. U.S. STRATEGY, AFRICAN KEY ACTORS, AND CHINA China-Africa trade will

  3. Did African Americans experience the 'Antebellum Puzzle'? Evidence from the United States Colored Troops during the Civil War.

    PubMed

    Haines, Michael R; Craig, Lee A; Weiss, Thomas

    2011-01-01

    The "Antebellum Puzzle" has been the subject of comment since the 1980s. It involves the paradox that, although the American economy was experiencing rapid economic growth in the several decades prior to the Civil War (1861-1865), the stature of native-born white males had been declining for the birth cohorts from the late 1820s. This was also true for free blacks (Komlos, 1992), but was apparently not true for slaves. This paper uses a sample of 8592 adult back males who were recruits to the United States Colored Troops during the Civil War. They were recruited significantly among ex-slaves. Recruits from the birth cohorts of 1838-1842 were then linked to characteristics of their counties of birth from the 1840 and 1850 U.S. Censuses. Unlike slaves in the coastal manifests, these African American recruits showed evidence of a decline in heights from the birth cohorts of the 1820s onwards. Unlike the native-white recruits, however, the characteristics of their counties of birth had relatively less power in explaining differences in heights. There was some support for the mortality hypothesis, but the nutrition hypothesis needs to be interpreted in light of the fact that slave owners has a strong interest in monitoring and controlling the diet of their slaves.

  4. 76 FR 6840 - Determinations Under the African Growth and Opportunity Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-08

    ... TRADE REPRESENTATIVE Determinations Under the African Growth and Opportunity Act AGENCY: Office of the... toward implementing and following, the customs procedures required by the African Growth and Opportunity... applicable visa requirements. See Visa Requirements Under the African Growth and Opportunity Act, 66 FR...

  5. 78 FR 16908 - Determinations Under the African Growth and Opportunity Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-19

    ... Determinations Under the African Growth and Opportunity Act AGENCY: Office of the United States Trade... following, the customs procedures required by the African Growth and Opportunity Act (AGOA). Therefore, as... the applicable visa requirements. See Visa Requirements Under the African Growth and Opportunity...

  6. Changing psychiatric perception of African-Americans with affective disorders.

    PubMed

    Jarvis, G Eric

    2012-12-01

    This article explored the origins and implications of the underdiagnosis of affective disorders in African-Americans. MEDLINE and old collections were searched using relevant key words. Reference lists from the articles that were gathered from this procedure were reviewed. The historical record indicated that the psychiatric perception of African-Americans with affective disorders changed significantly during the last 200 years. In the antebellum period, the mental disorders of slaves mostly went unnoticed. By the early 20th century, African-Americans were reported to have high rates of manic-depressive disorder compared with whites. By the mid-century, rates of manic-depressive disorder in African-Americans plummeted, whereas depression remained virtually nonexistent. In recent decades, diagnosed depression and bipolar disorder, whether in clinical or research settings, were inexplicably low in African-Americans compared with whites. Given these findings, American psychiatry needs to appraise the deep-seated effects of historical stereotypes on the diagnosis and treatment of African-Americans.

  7. [The suicide of slaves in São Paulo during the last two decades of slavery].

    PubMed

    Oliveira, Saulo Veiga; Oda, Ana Maria Galdini Raimundo

    2008-01-01

    News stories printed in Gazeta de Campinas (1871-1887) are used to investigate the views expressed at the time of the suicides of captives and freedmen in São Paulo province, and to discuss the data available. As suicide is a form of human behavior which cannot be reduced to one single explanation, it does not seem justifiable that amongst the slaves, these cases should also be taken as self-explanatory because of the conditions in which they occurred. By noting the circumstances in which these acts took place, it is hoped that the fallacy of oversimplified explanations can be belied, which refer to the suicide of slaves as quite simply being due to a 'dislike of captivity'.

  8. Numerical optimization algorithm for rotationally invariant multi-orbital slave-boson method

    NASA Astrophysics Data System (ADS)

    Quan, Ya-Min; Wang, Qing-wei; Liu, Da-Yong; Yu, Xiang-Long; Zou, Liang-Jian

    2015-06-01

    We develop a generalized numerical optimization algorithm for the rotationally invariant multi-orbital slave boson approach, which is applicable for arbitrary boundary constraints of high-dimensional objective function by combining several classical optimization techniques. After constructing the calculation architecture of rotationally invariant multi-orbital slave boson model, we apply this optimization algorithm to find the stable ground state and magnetic configuration of two-orbital Hubbard models. The numerical results are consistent with available solutions, confirming the correctness and accuracy of our present algorithm. Furthermore, we utilize it to explore the effects of the transverse Hund's coupling terms on metal-insulator transition, orbital selective Mott phase and magnetism. These results show the quick convergency and robust stable character of our algorithm in searching the optimized solution of strongly correlated electron systems.

  9. Verwey Metal-Insulator Transition in Magnetite from the Slave-Boson Approach

    NASA Astrophysics Data System (ADS)

    Sherafati, Mohammad; Satpathy, Sashi; Pettey, Dix

    2013-03-01

    We study the Verwey metal-insulator transition in magnetite (Ref.1) by solving a three-band extended Hubbard Hamiltonian for spinless fermions using the slave-boson approach, which also includes coupling to the local phonon modes. This model is suggested from the earlier density-functional studies of magnetite.(Ref.2) We first solve the 1D Hubbard model for the spinless fermions with nearest-neighbor interaction by both Gutzwiller variational and slave-boson methods and show that these two approaches yield different results unlike in the case of the standard Hubbard model, thereby clarifying some of the discrepancies in the literature (Ref.3), then we extend the formalism to three-band Hamiltonian for magnetite. The results suggest a metal-insulator transition at a critical value for the intersite interaction.

  10. Parallel processing data network of master and slave transputers controlled by a serial control network

    DOEpatents

    Crosetto, D.B.

    1996-12-31

    The present device provides for a dynamically configurable communication network having a multi-processor parallel processing system having a serial communication network and a high speed parallel communication network. The serial communication network is used to disseminate commands from a master processor to a plurality of slave processors to effect communication protocol, to control transmission of high density data among nodes and to monitor each slave processor`s status. The high speed parallel processing network is used to effect the transmission of high density data among nodes in the parallel processing system. Each node comprises a transputer, a digital signal processor, a parallel transfer controller, and two three-port memory devices. A communication switch within each node connects it to a fast parallel hardware channel through which all high density data arrives or leaves the node. 6 figs.

  11. Parallel processing data network of master and slave transputers controlled by a serial control network

    DOEpatents

    Crosetto, Dario B.

    1996-01-01

    The present device provides for a dynamically configurable communication network having a multi-processor parallel processing system having a serial communication network and a high speed parallel communication network. The serial communication network is used to disseminate commands from a master processor (100) to a plurality of slave processors (200) to effect communication protocol, to control transmission of high density data among nodes and to monitor each slave processor's status. The high speed parallel processing network is used to effect the transmission of high density data among nodes in the parallel processing system. Each node comprises a transputer (104), a digital signal processor (114), a parallel transfer controller (106), and two three-port memory devices. A communication switch (108) within each node (100) connects it to a fast parallel hardware channel (70) through which all high density data arrives or leaves the node.

  12. Reaction force/torque sensing in a master-slave robot system without mechanical sensors.

    PubMed

    Liu, Tao; Li, Chunguang; Inoue, Yoshio; Shibata, Kyoko

    2010-01-01

    In human-robot cooperative control systems, force feedback is often necessary in order to achieve high precision and high stability. Usually, traditional robot assistant systems implement force feedback using force/torque sensors. However, it is difficult to directly mount a mechanical force sensor on some working terminals, such as in applications of minimally invasive robotic surgery, micromanipulation, or in working environments exposed to radiation or high temperature. We propose a novel force sensing mechanism for implementing force feedback in a master-slave robot system with no mechanical sensors. The system consists of two identical electro-motors with the master motor powering the slave motor to interact with the environment. A bimanual coordinated training platform using the new force sensing mechanism was developed and the system was verified in experiments. Results confirm that the proposed mechanism is capable of achieving bilateral force sensing and mirror-image movements of two terminals in two reverse control directions.

  13. "Ask a slave" and interpreting race on public history's front line: interview with Azie Mira Dungey.

    PubMed

    Dungey, Azie Mira; Tyson, Amy M

    2014-02-01

    In this interview, Azie Mira Dungey (creator of the web series, "Ask a Slave") and Amy M. Tyson (Associate Professor of History at DePaul University and author of The Wages of History: Emotional Labor on Public History's Front Lines) discuss Dungey's web series, as well as her experiences as a living history interpreter at both the Smithsonian Museum of American History and at Mount Vernon.

  14. Z2 slave-spin theory of a strongly correlated Chern insulator

    NASA Astrophysics Data System (ADS)

    Prychynenko, Diana; Huber, Sebastian D.

    2016-01-01

    We calculate the phase diagram of the topological honeycomb model in the presence of strong interactions. We concentrate on half filling and employ a Z2 slave-spin method to find a band insulator with staggered density, a spin-density-wave and a Mott insulating phase. Both the band insulator and the spin-density wave come in various topological varieties. Finally, we calculate the response function relevant for lattice modulation spectroscopy with cold atomic gases in optical lattices.

  15. Of broken bonds and bondage: an analysis of loss in the Slave Narrative Collection.

    PubMed

    Laurie, Anna; Neimeyer, Robert A

    2010-03-01

    Relatively few scholars have made use of the Slave Narrative Collection, a collection of more than 2,300 autobiographical narratives detailing the lives of people who had been born into slavery. Housed at the Library of Congress, the Collection was gathered during the 1930s under the direction of the Federal Writers Project. Research derived from the Collection thus far has dealt primarily with the experience of slavery as a whole. The present study focuses on loss as it was experienced by former slaves. This qualitative study used a grounded theory approach to analyze 48 narratives. Results culminated in a core category or central theme that for former slaves loss was both a cause and a consequence of dehumanization. Findings also suggested that people experienced loss as a result of witnessing or experiencing violence and of living in deprivation and fear. Other losses included losses of hope and identity. Losses associated with the pain and suffering of family members were hardest to bear.

  16. Redox preconditioning deep cratonic lithosphere for kimberlite genesis - evidence from the central Slave Craton.

    PubMed

    Yaxley, G M; Berry, A J; Rosenthal, A; Woodland, A B; Paterson, D

    2017-12-01

    We present the first oxygen fugacity (fO2) profile through the cratonic lithospheric mantle under the Panda kimberlite (Ekati Diamond Mine) in the Lac de Gras kimberlite field, central Slave Craton, northern Canada. Combining this data with new and existing data from garnet peridotite xenoliths from an almost coeval kimberlite (A154-N) at the nearby Diavik Diamond Mine demonstrates that the oxygen fugacity of the Slave cratonic mantle varies by several orders of magnitude as a function of depth and over short lateral distances. The lower part of the diamond-bearing Slave lithosphere (>120-130 km deep) has been oxidized by up to 4 log units in fO2, and this is clearly linked to metasomatic enrichment. Such coupled enrichment and oxidation was likely caused by infiltrating carbonate-bearing, hydrous, silicate melts in the presence of diamond, a process proposed to be critical for "pre-conditioning" deep lithospheric mantle and rendering it suitable for later generation of kimberlites and other SiO2-undersaturated magmas.

  17. Asynchronous master-slave parallelization of differential evolution for multi-objective optimization.

    PubMed

    Depolli, Matjaž; Trobec, Roman; Filipič, Bogdan

    2013-01-01

    In this paper, we present AMS-DEMO, an asynchronous master-slave implementation of DEMO, an evolutionary algorithm for multi-objective optimization. AMS-DEMO was designed for solving time-intensive problems efficiently on both homogeneous and heterogeneous parallel computer architectures. The algorithm is used as a test case for the asynchronous master-slave parallelization of multi-objective optimization that has not yet been thoroughly investigated. Selection lag is identified as the key property of the parallelization method, which explains how its behavior depends on the type of computer architecture and the number of processors. It is arrived at analytically and from the empirical results. AMS-DEMO is tested on a benchmark problem and a time-intensive industrial optimization problem, on homogeneous and heterogeneous parallel setups, providing performance results for the algorithm and an insight into the parallelization method. A comparison is also performed between AMS-DEMO and generational master-slave DEMO to demonstrate how the asynchronous parallelization method enhances the algorithm and what benefits it brings compared to the synchronous method.

  18. Design, Development, and Evaluation of a Master-Slave Surgical System for Breast Biopsy under Continuous MRI*

    PubMed Central

    Yang, Bo; Roys, Steven; Tan, U-Xuan; Philip, Mathew; Richard, Howard; Gullapalli, Rao; Desai, Jaydev P.

    2013-01-01

    Magnetic Resonance Imaging (MRI) provides superior soft-tissue contrast in cancer diagnosis compared to other imaging modalities. However, the strong magnetic field inside the MRI bore along with limited scanner bore size poses significant challenges. Since current approaches in breast biopsy using MR images is primarily a blind targeting approach, it is necessary to develop a MRI-compatible robot that can avoid multiple needle insertions into the breast tissue. This MRI-compatible robotic system could potentially lead to improvement in the targeting accuracy and reduce sampling errors. A master-slave surgical system has been developed comprising of a MRI-compatible slave robot which consists of one piezo motor and five pneumatic cylinders connected by long pneumatic transmission lines. The slave robot follows the configuration of the master robot, which provides an intuitive manipulation interface for the physician and operates inside the MRI bore to adjust the needle position and orientation and perform needle insertion task. Based on the MRI experiments using the slave robot, there was no significant distortion in the images and hence the slave robot can be safely operated inside the MRI with minimal loss in signal-to-noise ratio (SNR). Ex vivo and in vivo experiments have been conducted to evaluate the performance of the master-slave surgical system. PMID:25313266

  19. Seeing beyond the Local Context: The Understandings of Slavery and the Slave Trade of Students in Reunion Island Schools

    ERIC Educational Resources Information Center

    Vitale, Philippe

    2013-01-01

    In the new millennium model of low definition curriculum, teachers have professional latitude to deliver prescribed disciplinary content through a range of pedagogical and assessment orientations. The rhetoric is that with carefully crafted practice, the goal of high quality/high equity learning outcomes can be achieved for all students. This…

  20. Voyaging to the Heart of Darkness - The Slave Trade and the 1841 Niger Expedition as Precursors to Modern Interplanetary Colonization

    NASA Astrophysics Data System (ADS)

    Sivier, D. J.

    Arguments for the commercialisation and colonisation of space have often been supported with examples from terrestrial history, which closely parallel the problems and strategies facing extraterrestrial colonisation. A particularly instructive episode in British colonial history was the 1841 expedition to the Niger. Not only did this feature technology prefiguring that later adopted in space vehicle life support systems, but the mission itself and its collapse provide important lessons on the necessity of mobilising public support for such missions, avoid- ance of severe casualties and utility of a strategy of exploration by proxy and gradual, incremental approach to exploration.

  1. Microxenoliths from the Slave craton: Archives of diamond formation along fluid conduits

    NASA Astrophysics Data System (ADS)

    Aulbach, Sonja; Stachel, Thomas; Heaman, Larry M.; Carlson, Jon A.

    2011-10-01

    A suite of 23 diamondiferous microxenoliths from the Ekati kimberlites in the central Slave craton was studied to elucidate the tectonothermal evolution of the lithosphere during craton formation and modification along craton margins, and associated diamond formation. Major- and trace-element abundances of eclogites (n = 16) reveal the presence of two compositionally distinct suites: a group of three eclogites with typical gabbroic trace-element patterns (flat REE N and low ΣREE, positive Sr N and Pb N, negative Zr N anomalies) and a group of 13 eclogites that are characterised by lower Mg#, Cr, Sc and Sr combined with higher Al 2O 3, TiO 2 and Na 2O, and a conspicuously stepped REE pattern with lower LREE/HREE. Inclusions in diamonds from the central Slave craton consistently plot with the latter group. The unusual trace-element characteristics of the second group are strikingly similar to those produced along fluid conduits in younger subduction zones, where infiltration of a metasomatic fluid induced eclogitisation. Eclogitic diamonds contain an average of 540 at.ppm nitrogen that is poorly aggregated (12% in the B centre), similar to eclogitic diamonds recovered from the A154 kimberlite (Diavik Mine, ~ 30 km southeast) that were dated to 1.85 Ga and linked to subduction at the western craton margin. This suggests that (1) by 1.85 Ga subduction-related reactive fluid transport and element mobilisation similar to younger examples were established, and (2) this fluid flow not only catalysed eclogitisation of subducting oceanic crust, but also was a prerequisite for the majority of eclogitic diamond formation beneath the central Slave craton. Harzburgitic and lherzolitic diamondiferous microxenoliths (n = 4) may document diamond formation in the Slave craton prior to emplacement of eclogites. Peridotitic garnets have sinusoidal REE-patterns with strong depletions in Ti, consistent with carbonate-melt or fluid metasomatism that may have also prompted diamond growth

  2. Race consciousness and the health of African Americans.

    PubMed

    Watts, Rosalyn J

    2003-01-01

    The historical experience of African Americans in our country has been shaped by the institution of slavery, dehumanization of blacks, segregation, pursuit of civil rights, and racism in contemporary American society. Disparities in health care provide compelling evidence that issues of race or skin color for the descendants of slaves and other ethnic minorities persist in the 21st century. Nurses providing care for African Americans must bridge the racial divide and incorporate culturally relevant content in the health history. As an integral aspect of their professional growth as culturally competent health care providers, they must incorporate the idea of "race consciousness" which is described as an awareness of the historical journey of the group, knowledge of disparities in health care for the people, and a self appraisal of one's attitudes and biases toward the group.

  3. African Aesthetics

    ERIC Educational Resources Information Center

    Abiodun, Rowland

    2001-01-01

    No single traditional discipline can adequately supply answers to the many unresolved questions in African art history. Because of the aesthetic, cultural, historical, and, not infrequently, political biases, already built into the conception and development of Western art history, the discipline of art history as defined and practiced in the West…

  4. African Pentecostalism

    ERIC Educational Resources Information Center

    Garrard, David J.

    2009-01-01

    The diversity of African Pentecostalism, its early colonial and missionary history and its current characteristics are described and analysed. Reference is made to methods of training and forms of leadership, and suggestions are made about the reasons for its growth and persistence. (Contains 19 notes.)

  5. The Paternal Landscape along the Bight of Benin – Testing Regional Representativeness of West-African Population Samples Using Y-Chromosomal Markers

    PubMed Central

    Larmuseau, Maarten H. D.; Vessi, Andrea; Jobling, Mark A.; Van Geystelen, Anneleen; Primativo, Giuseppina; Biondi, Gianfranco; Martínez-Labarga, Cristina; Ottoni, Claudio; Decorte, Ronny; Rickards, Olga

    2015-01-01

    Patterns of genetic variation in human populations across the African continent are still not well studied in comparison with Eurasia and America, despite the high genetic and cultural diversity among African populations. In population and forensic genetic studies a single sample is often used to represent a complete African region. In such a scenario, inappropriate sampling strategies and/or the use of local, isolated populations may bias interpretations and pose questions of representativeness at a macrogeographic-scale. The non-recombining region of the Y-chromosome (NRY) has great potential to reveal the regional representation of a sample due to its powerful phylogeographic information content. An area poorly characterized for Y-chromosomal data is the West-African region along the Bight of Benin, despite its important history in the trans-Atlantic slave trade and its large number of ethnic groups, languages and lifestyles. In this study, Y-chromosomal haplotypes from four Beninese populations were determined and a global meta-analysis with available Y-SNP and Y-STR data from populations along the Bight of Benin and surrounding areas was performed. A thorough methodology was developed allowing comparison of population samples using Y-chromosomal lineage data based on different Y-SNP panels and phylogenies. Geographic proximity turned out to be the best predictor of genetic affinity between populations along the Bight of Benin. Nevertheless, based on Y-chromosomal data from the literature two population samples differed strongly from others from the same or neighbouring areas and are not regionally representative within large-scale studies. Furthermore, the analysis of the HapMap sample YRI of a Yoruban population from South-western Nigeria based on Y-SNPs and Y-STR data showed for the first time its regional representativeness, a result which is important for standard population and forensic genetic applications using the YRI sample. Therefore, the uniquely

  6. African-American Biography.

    ERIC Educational Resources Information Center

    Martin, Ron

    1995-01-01

    Suggests sources of information for African American History Month for library media specialists who work with students in grades four through eight. Gale Research's "African-American Reference Library," which includes "African-America Biography,""African-American Chronology," and "African-American Almanac,"…

  7. International Trade and Protectionism.

    ERIC Educational Resources Information Center

    Stanford Univ., CA. Stanford Program on International and Cross Cultural Education.

    This unit is designed to investigate the reasons for international trade and the issue of trade protectionism by focusing on the case study of the U.S. trade relationship with Taiwan. The unit begins with a simulation that highlights the concepts of global interdependence, the need for international trade, and the distribution of the world's…

  8. "[No] doctor but my master": Health reform and antislavery rhetoric in Harriet Jacobs's Incidents in the life of a slave girl.

    PubMed

    Berry, Sarah L

    2014-03-01

    This essay examines Harriet Jacobs's Incidents in the Life of a Slave Girl (1861) in light of new archival findings on the medical practices of Dr. James Norcom (Dr. Flint in the narrative). While critics have sharply defined the feminist politics of Jacobs's sexual victimization and resistance, they have overlooked her medical experience in slavery and her participation in reform after escape. I argue that Jacobs uses the rhetoric of a woman-led health reform movement underway during the 1850s to persuade her readers to end slavery. This essay reconstructs both contexts, revealing that Jacobs links enslaved women's physical and sexual vulnerability with her female readers' fears of male doctors' threats to modesty and of their standard bleed-and-purge treatments. Jacobs illustrates that slavery damages women's health as much as heroic medicine, and thus merits the political activism of her readers. Specifically, Jacobs dramatizes her conflicts with the rapacious physician-master at moments that are crucial to women's health: marriage, pregnancy, childbirth, and motherhood. Ultimately, this essay advances a new understanding of the role of health reform in social change: it galvanized other movements such as women's rights and abolition, particularly around issues of bodily autonomy for women and African Americans.

  9. Self-oscillations of a third order PLL in periodic and chaotic mode and its tracking in a slave PLL

    NASA Astrophysics Data System (ADS)

    Sarkar, B. C.; Chakraborty, S.

    2014-03-01

    The dynamics of a third order phase locked loop (PLL) with a resonant low pass filter (LPF) has been studied numerically in the parameter space of the system. The range of stable synchronous operating zone of the PLL, expressed in terms of system and signal parameters, is estimated. The obtained results are in agreement with the analytically predicted results in the literature. The PLL dynamics in the unstable region is found to have a sequence of period doubling bifurcation and chaos. In the master-slave mode of operation of two 3rd order PLLs, the slave PLL can track the periodic as well as chaotic dynamics of the master PLL for a narrow range of effective frequency offset when other design parameters are within the stable zone as predicted for an isolated PLL. The synchronization of the master and slave PLLs in this condition is proved to be a generalized one using the auxiliary slave system approach. Experimental observations on prototype hardware circuits for an isolated PLL and for a master-slave PLL arrangement are also given.

  10. Visual cueing considerations in Nap-of-the-Earth helicopter flight head-slaved helmet-mounted displays

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Kohn, Silvia

    1993-01-01

    The pilot's ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays, commonly used in Apache and Cobra helicopter night operations, originates from a relatively narrow field-of-view Forward Looking Infrared Radiation Camera, gimbal-mounted at the nose of the aircraft and slaved to the pilot's line-of-sight, in order to obtain a wide-angle field-of-regard. Pilots have encountered considerable difficulties in controlling the aircraft by these devices. Experimental simulator results presented here indicate that part of these difficulties can be attributed to head/camera slaving system phase lags and errors. In the presence of voluntary head rotation, these slaving system imperfections are shown to impair the Control-Oriented Visual Field Information vital in vehicular control, such as the perception of the anticipated flight path or the vehicle yaw rate. Since, in the presence of slaving system imperfections, the pilot will tend to minimize head rotation, the full wide-angle field-of-regard of the line-of-sight slaved Helmet-Mounted Display, is not always fully utilized.

  11. African Trypanosomiasis

    DTIC Science & Technology

    2011-06-01

    infection by protozoan hemo- flagellates of the Trypanosoma brucei complex, 2 subspe- cies of which cause disease in humans: Trypanosoma bru- cei gambiense...public release; distribution unlimited 13. SUPPLEMENTARY NOTES See also ADA545141. Chapter 3 from e-book, Topics on the Pathology of Protozoan and...the brief ferry crossing. 2 3 • Topics on The paThology of proTozoan and invasive arThropod diseases Three severe epidemics of African trypanosomiasis

  12. Slave-boson mean field versus quantum Monte Carlo results for the Hubbard model

    NASA Astrophysics Data System (ADS)

    Lilly, L.; Muramatsu, A.; Hanke, W.

    1990-09-01

    The one-band Hubbard model is considered in the slave-boson formulation first introduced by Kotliar and Ruckenstein. It is shown that a mean-field approximation, where broken-symmetry states appropriate for a bipartite lattice are allowed, leads to a quantitative agreement with quantum Monte Carlo results for local observables over a wide range of interactions (0<=1). Thus, our saddle-point solutions constitute an excellent starting point for a systematic treatment of fluctuations.

  13. Slave Boson Theory of Orbital Differentiation with Crystal Field Effects: Application to UO2

    NASA Astrophysics Data System (ADS)

    Lanatà, Nicola; Yao, Yongxin; Deng, Xiaoyu; Dobrosavljević, Vladimir; Kotliar, Gabriel

    2017-03-01

    We derive an exact operatorial reformulation of the rotational invariant slave boson method, and we apply it to describe the orbital differentiation in strongly correlated electron systems starting from first principles. The approach enables us to treat strong electron correlations, spin-orbit coupling, and crystal field splittings on the same footing by exploiting the gauge invariance of the mean-field equations. We apply our theory to the archetypical nuclear fuel UO2 and show that the ground state of this system displays a pronounced orbital differentiation within the 5 f manifold, with Mott-localized Γ8 and extended Γ7 electrons.

  14. Non-equilibrium slave bosons approach to quantum pumping in interacting quantum dots

    NASA Astrophysics Data System (ADS)

    Citro, Roberta; Romeo, Francesco

    2016-03-01

    We review a time-dependent slave bosons approach within the non-equilibrium Green's function technique to analyze the charge and spin pumping in a strongly interacting quantum dot. We study the pumped current as a function of the pumping phase and of the dot energy level and show that a parasitic current arises, beyond the pure pumping one, as an effect of the dynamical constraints. We finally illustrate an all-electrical mean for spin-pumping and discuss its relevance for spintronics applications.

  15. Broadband master-slave interferometry using a super-continuum source

    NASA Astrophysics Data System (ADS)

    Maria, M.; Marques, M. J. M.; Costa, C.; Bradu, A.; Feuchter, T.; Leick, L.; Podoleanu, A. G.

    2016-03-01

    In this report we applied the principle of Master-Slave Interferometry (MSI) to an Optical Coherence Tomography (OCT) employing a Super-Continuum (SC) light source. A-scans and B-scan images of biological and non-biological sample are presented in order to demonstrate similar performance with the images obtained with the resampled Fourier Transform (FT) based OCT technique. Dispersion tolerance of MSI method is demonstrated as a constant axial resolution over the depth range even though dispersion is left uncompenstaed in the system.

  16. The slave-fermion approach of spin fluctuations in ferromagnet metals

    NASA Astrophysics Data System (ADS)

    Hu, C. D.

    2015-11-01

    In this work we propose a method to treat the spin fluctuations in itinerant ferromagnets. It is able to do calculation with a convergent series. The slave fermion method is applied to separate the charge (denoted by fermions) and spin (denoted by bosons) degrees of freedom. The spin operators are then replaced by the Schwinger boson fields. This way, the interaction term in the model can be reduced to a very simple form and can be teated without difficulty. Finally the equations of motion are derived in order to obtain the forms of Green's functions of fermions and bosons. The result is applied to the calculation of resistivity as a function temperature.

  17. A compact cascaded microring filter with two master rings and two slave rings for sensing application

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Li, Zhi-quan; Tong, Kai

    2014-01-01

    In this paper, an ultra compact cascaded microring filter consisting of two master rings with radius of 2.5 μm and two slave rings with radius of 1 μm is presented and studied theoretically. The filter with a very large free spectral range (FSR) of 206 nm, a deep extinction ratio of 23 dB, a high quality factor of 2.76×105, and greatly suppressed spurious modes of less than 0.1 dB is achieved. The spectral responses of the filter are simulated by transfer matrix method, and the results show that this filter has a great potential of sensor application.

  18. A SNP test to identify Africanized honeybees via proportion of 'African' ancestry.

    PubMed

    Chapman, Nadine C; Harpur, Brock A; Lim, Julianne; Rinderer, Thomas E; Allsopp, Michael H; Zayed, Amro; Oldroyd, Benjamin P

    2015-11-01

    The honeybee, Apis mellifera, is the world's most important pollinator and is ubiquitous in most agricultural ecosystems. Four major evolutionary lineages and at least 24 subspecies are recognized. Commercial populations are mainly derived from subspecies originating in Europe (75-95%). The Africanized honeybee is a New World hybrid of A. m. scutellata from Africa and European subspecies, with the African component making up 50-90% of the genome. Africanized honeybees are considered undesirable for bee-keeping in most countries, due to their extreme defensiveness and poor honey production. The international trade in honeybees is restricted, due in part to bans on the importation of queens (and semen) from countries where Africanized honeybees are extant. Some desirable strains from the United States of America that have been bred for traits such as resistance to the mite Varroa destructor are unfortunately excluded from export to countries such as Australia due to the presence of Africanized honeybees in the USA. This study shows that a panel of 95 single nucleotide polymorphisms, chosen to differentiate between the African, Eastern European and Western European lineages, can detect Africanized honeybees with a high degree of confidence via ancestry assignment. Our panel therefore offers a valuable tool to mitigate the risks of spreading Africanized honeybees across the globe and may enable the resumption of queen and bee semen imports from the Americas.

  19. Steering a simulated unmanned aerial vehicle using a head-slaved camera and HMD

    NASA Astrophysics Data System (ADS)

    de Vries, Sjoerd C.; Padmos, Pieter

    1997-06-01

    Military use of unmanned aerial vehicles (UAVs) is gaining importance. Video cameras in these devices are often operated with joysticks and their image is displayed on a CRT. In this experiment, the simulated camera of a simulated UAV was slaved to the operator's head movements and displayed using a helmet mounted display (HMD). The task involved maneuvering a UAV along a winding course marked by tress. The influence of several parameters of the set-up on a set of flight handling characteristics was assessed. To enable variation of FOV and to study the effect of the HMD optics, a simulated HMD consisting of a head slaved window, was projected on a screen. One of the FOVs, generated in this way, corresponded with the FOV of the real HMD, enabling a comparison. The results show that the simulated HMD yields a significantly better performance that the real HMD. Performance with a FOV of 17 degrees is significantly lower than with 34 or 57 degrees. An image lag of 50 ms, typical of pan-and-tilt servo motor systems, has a small but significant influence on steering accuracy. Monocular and stereoscopic presentation did not result in significant performance differences.

  20. 3-D Structure of the Slave and Rae Cratons Provides Clues to Their Construction

    NASA Astrophysics Data System (ADS)

    Snyder, D. B.

    2013-12-01

    Deep geologic structures within cratons that make up continental cores were long neglected. Recently acquired geophysical data from large observational arrays and geochemical data resulting from exploration for diamond has now made possible co-registration of large-scale (400-km depth), truly 3-dimensional data sets. P-waves, surface waves and magnetotelluric observations provide 3-D wavespeed and conductivity models. Multi-azimuthal receiver functions map seismic discontinuity surfaces in 3-D. Xenolith suites erupted in kimberlites provide rock samples at key lithospheric depths, albeit at sparsely distributed locations. These multi-disciplinary models are becoming available for several key cratons worldwide; here the deep structure of the Slave and Rae cratons of the Canadian Shield is described. Lithospheric layers with tapered, wedge-shaped margins are common. Slave craton layers are sub-horizontal and indicate construction of the craton core at 2.7 Ga by underthrusting and flat stacking of lithosphere. The central Rae craton has predominantly dipping discontinuities that indicate construction at 1.9 Ga by thrusting similar to that observed in crustal ';thick-skinned' fold-and-thrust belts. 3-D mapping of conductivity and metasomatism, the latter via mineral recrystallization and resetting of isotopic ages, overprints primary structures in both cratons. Distribution of more conductivitve mantle suggests that assumed causative pervasive metasomatism occurs at 100-200 km depths with ';chimneys' reaching to shallower depths, typically in locations where kimberlites or mineralization has occurred.

  1. Self-consistent slave rotor mean-field theory for strongly correlated systems

    NASA Astrophysics Data System (ADS)

    Zhao, E.; Paramekanti, A.

    2007-11-01

    Building on the work by Florens and Georges [Phys. Rev. B 70, 035114 (2004)], we formulate and study a self-consistent slave rotor mean-field theory for strongly correlated systems. This approach views the electron, in the strong correlation regime, as a composite of a neutral spinon and a charged rotor field. We solve the coupled spinon-rotor model self-consistently using a cluster mean-field theory for the rotors and various Ansätze for the spinon ground state. We illustrate this approach with a number of examples relevant to ongoing experiments in strongly correlated electronic systems such as (i) the phase diagram of the isotropic triangular lattice organic Mott insulators, (ii) quasiparticle excitations and tunneling asymmetry in the weakly doped cuprate superconductors, and (iii) the cyclotron mass of carriers in commensurate spin-density wave and U(1) staggered flux (or d -density wave) normal states of the underdoped cuprates. We compare the estimated cyclotron mass with results from recent quantum oscillation experiments on ortho-II YBa2Cu3O6.5 by Doiron-Leyraud [Nature (London) 447, 565 (2007)] which appear to find Fermi pockets in the magnetic field induced normal state. We comment on the relation of this normal ground state to Fermi arcs seen in photoemission experiments above Tc . This slave rotor mean-field theory can be generalized to study inhomogeneous states and strongly interacting models relevant to ultracold atoms in optical lattices.

  2. Lithospheric architecture of the Slave craton, northwest Canada, as determined from an interdisciplinary 3-D model

    NASA Astrophysics Data System (ADS)

    Snyder, D. B.; Hillier, M. J.; Kjarsgaard, B. A.; de Kemp, E. A.; Craven, J. A.

    2014-05-01

    geologic structures characteristic of mantle lithosphere within cratons found in continent interiors are interpreted using geo-registered diverse data sets from the Slave craton of northwest Canada. We developed and applied a new method for mapping seismic discontinuities in three dimensions using multiyear observations at sparse, individual broadband receivers. New, fully 3-D conductivity models used all available magnetotelluric data. Discontinuity surfaces and conductivity models were geo-registered with previously published P-wave and surface-wave velocity models to confirm first-order structures such as a midlithosphere discontinuity. Our 3-D model to 400 km depth was calibrated by "drill hole" observations derived from xenolith suites extracted from kimberlites. A number of new structural discontinuities emerge from direct comparison of coregistered data sets and models. Importantly, we distinguish primary mantle layers from secondary features related to younger metasomatism. Subhorizontal Slave craton layers with tapered, wedge-shaped margins indicate construction of the craton core at 2.7 Ga by underthrusting and flat stacking of lithosphere. Mapping of conductivity and metasomatism in 3-D, the latter inferred via mineral recrystallization and resetting of isotopic ages in xenoliths, indicates overprinting of the primary layered structures. The observed distribution of relatively conductive mantle at 100-200 km depths is consistent with pervasive metasomatism; vertical "chimneys" reaching to crustal depths in locations where kimberlites erupted or where Au mineralization is known.

  3. Modeling and Dynamic Analysis of Paralleled dc/dc Converters With Master-Slave Current Sharing Control

    NASA Technical Reports Server (NTRS)

    Rajagopalan, J.; Xing, K.; Guo, Y.; Lee, F. C.; Manners, Bruce

    1996-01-01

    A simple, application-oriented, transfer function model of paralleled converters employing Master-Slave Current-sharing (MSC) control is developed. Dynamically, the Master converter retains its original design characteristics; all the Slave converters are forced to depart significantly from their original design characteristics into current-controlled current sources. Five distinct loop gains to assess system stability and performance are identified and their physical significance is described. A design methodology for the current share compensator is presented. The effect of this current sharing scheme on 'system output impedance' is analyzed.

  4. Modeling and Dynamic Analysis of Paralleled of dc/dc Converters with Master-Slave Current Sharing Control

    NASA Technical Reports Server (NTRS)

    Rajagopalan, J.; Xing, K.; Guo, Y.; Lee, F. C.; Manners, Bruce

    1996-01-01

    A simple, application-oriented, transfer function model of paralleled converters employing Master-Slave Current-sharing (MSC) control is developed. Dynamically, the Master converter retains its original design characteristics; all the Slave converters are forced to depart significantly from their original design characteristics into current-controlled current sources. Five distinct loop gains to assess system stability and performance are identified and their physical significance is described. A design methodology for the current share compensator is presented. The effect of this current sharing scheme on 'system output impedance' is analyzed.

  5. Time and frequency transfer by the Master-Slave Returnable Timing System technique - Application to solar power transmission

    NASA Technical Reports Server (NTRS)

    Lindsey, W. C.; Kantak, A. V.

    1979-01-01

    The concept of the Master Slave Returnable Timing System (MSRTS) is presented which combines the advantages of the master slave (MS) and the Returnable Timing System (RTS) for time and frequency transfer. The basic idea of MSRTS is to send the time-frequency signal received at a particular node back to the sending node. The delay accumulated by this return signal is used to advance the phase of the master (sending) node thereby canceling the effect of the delay introduced by the path. The method can be used in highly accurate clock distribution systems required in avionics, computer communications, and large retrodirective phased arrays such as the Solar Power Satellite.

  6. Peridotitic diamonds from the Slave and the Kaapvaal cratons—similarities and differences based on a preliminary data set

    NASA Astrophysics Data System (ADS)

    Stachel, Thomas; Harris, Jeff W.; Tappert, Ralf; Brey, Gerhard P.

    2003-12-01

    A comparison of the diamond productions from Panda (Ekati Mine) and Snap Lake with those from southern Africa shows significant differences: diamonds from the Slave typically are un-resorbed octahedrals or macles, often with opaque coats, and yellow colours are very rare. Diamonds from the Kaapvaal are dominated by resorbed, dodecahedral shapes, coats are absent and yellow colours are common. The first two features suggest exposure to oxidizing fluids/melts during mantle storage and/or transport to the Earth's surface, for the Kaapvaal diamond population. Comparing peridotitic inclusions in diamonds from the central and southern Slave (Panda, DO27 and Snap Lake kimberlites) and the Kaapvaal indicates that the diamondiferous mantle lithosphere beneath the Slave is chemically less depleted. Most notable are the almost complete absence of garnet inclusions derived from low-Ca harzburgites and a generally lower Mg-number of Slave inclusions. Geothermobarometric calculations suggest that Slave diamonds originally formed at very similar thermal conditions as observed beneath the Kaapvaal (geothermal gradients corresponding to 40-42 mW/m 2 surface heat flow), but the diamond source regions subsequently cooled by about 100-150 °C to fall on a 37-38 mW/m 2 (surface heat flow) conductive geotherm, as is evidenced from touching (re-equilibrated) inclusions in diamonds, and from xenocrysts and xenoliths. In the Kaapvaal, a similar thermal evolution has previously been recognized for diamonds from the De Beers Pool kimberlites. In part very low aggregation levels of nitrogen impurities in Slave diamonds imply that cooling occurred soon after diamond formation. This may relate elevated temperatures during diamond formation to short-lived magmatic perturbations. Generally high Cr-contents of pyrope garnets (inside and outside of diamonds) indicate that the mantle lithosphere beneath the Slave originally formed as a residue of melt extraction at relatively low pressures (within

  7. Counter-Discursive and Erotic Agency: The Case of the Black Slaves in Miguel De Cervantes's "El Celoso Extremeño"

    ERIC Educational Resources Information Center

    Ruiz, Eduardo

    2014-01-01

    Cervantes's "novela" creates a complex protagonist due in part to the involvement of the slaves' destructive and creative energies: a linguistic and erotic paradox. Linguistically the female slave foregrounds the historical dichotomy between "ladinos" and "bozales" and the related problematic of conversion,…

  8. Emissions Trading Resources

    EPA Pesticide Factsheets

    Learn about emissions trading programs, also known as cap and trade programs, which are market-based policy tools for protecting human health and the environment by controlling emissions from a group of sources.

  9. Illicit Drug Trafficking in West Africa -- Primary Surveillance Radar Introduction

    DTIC Science & Technology

    2012-03-22

    social cohesion.9 West African Trade West Africa has a long history of trade . This was not restricted to the export of slaves and tropical...Kola stimulant, cannabis and alcohol were all legally traded between Europe, the Middle East and the Sahara. Given West Africa’s long history of...West African Membership in Multilateral Anti-Crime Agreements or Bodies West African nations know and understand the problem of illicit trade but

  10. African Outreach Workshop 1974.

    ERIC Educational Resources Information Center

    Schmidt, Nancy J.

    This report discusses the 1974 African Outreach Workshop planned and coordinated by the African Studies Program at the University of Illinois at Urbana-Champaign. Its major aim was to assist teachers in developing curriculum units on African using materials available in their local community. A second aim was for the African Studies Program to…

  11. Metal Trades Technology Curriculum.

    ERIC Educational Resources Information Center

    EASTCONN Regional Educational Services Center, North Windham, CT.

    This curriculum guide provides materials for a metal trades technology course of study at the high school level. Its stated purpose is to help students acquire the trade knowledge necessary to function effectively in the shipfitting, welding, and piping trades. Contents include: a course description, a list of general objectives; lists of…

  12. 75 FR 40774 - Determination Under the African Growth and Opportunity Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the African Growth and Opportunity Act AGENCY: Committee...'' and ``ethnic printed fabrics'' and qualify for preferential treatment under the African Growth and... Growth and Opportunity Act (Title I of the Trade and Development Act of 2000, Pub. L. No....

  13. Physiological control of dual rotary pumps as a biventricular assist device using a master/slave approach.

    PubMed

    Stevens, Michael C; Wilson, Stephen; Bradley, Andrew; Fraser, John; Timms, Daniel

    2014-09-01

    Dual rotary left ventricular assist devices (LVADs) can provide biventricular mechanical support during heart failure. Coordination of left and right pump speeds is critical not only to avoid ventricular suction and to match cardiac output with demand, but also to ensure balanced systemic and pulmonary circulatory volumes. Physiological control systems for dual LVADs must meet these objectives across a variety of clinical scenarios by automatically adjusting left and right pump speeds to avoid catastrophic physiological consequences. In this study we evaluate a novel master/slave physiological control system for dual LVADs. The master controller is a Starling-like controller, which sets flow rate as a function of end-diastolic ventricular pressure (EDP). The slave controller then maintains a linear relationship between right and left EDPs. Both left/right and right/left master/slave combinations were evaluated by subjecting them to four clinical scenarios (rest, postural change, Valsalva maneuver, and exercise) simulated in a mock circulation loop. The controller's performance was compared to constant-rotational-speed control and two other dual LVAD control systems: dual constant inlet pressure and dual Frank-Starling control. The results showed that the master/slave physiological control system produced fewer suction events than constant-speed control (6 vs. 62 over a 7-min period). Left/right master/slave control had lower risk of pulmonary congestion than the other control systems, as indicated by lower maximum EDPs (15.1 vs. 25.2-28.4 mm Hg). During exercise, master/slave control increased total flow from 5.2 to 10.1 L/min, primarily due to an increase of left and right pump speed. Use of the left pump as the master resulted in fewer suction events and lower EDPs than when the right pump was master. Based on these results, master/slave control using the left pump as the master automatically adjusts pump speed to avoid suction and increases pump flow

  14. Exact results in a slave boson saddle point approach for a strongly correlated electron model

    SciTech Connect

    Fresard, Raymond; Kopp, Thilo

    2008-08-15

    We revisit the Kotliar-Ruckenstein (KR) slave boson saddle point evaluation for a two-site correlated electron model. As the model can be solved analytically, it is possible to compare the KR saddle point results with the exact many-particle levels. The considered two-site cluster mimics an infinite-U single-impurity Anderson model with a nearest-neighbor Coulomb interaction: one site is strongly correlated with an infinite local Coulomb repulsion, which hybridizes with the second site, on which the local Coulomb repulsion vanishes. Making use of the flexibility of the representation, we introduce appropriate weight factors in the KR saddle point scheme. Ground-state and all excitation levels agree with the exact diagonalization results. Thermodynamics and correlation functions may be recovered in a suitably renormalized saddle point evaluation.

  15. Development of robot hand with pneumatic actuator and construct of master-slave system.

    PubMed

    Nishino, Shinya; Tsujiuchi, Nobutaka; Koizumi, Takayuki; Komatsubara, Hiroyuki; Kudawara, Tatuwo; Shimizu, Mikio

    2007-01-01

    Recently, research has concentrated on robots that can coexist with people and be of use to them. Such a robot needs to be both safe and flexible. Here, we use a pneumatic actuator as the driving source of a robot hand. We develop a pneumatic actuator driven by low pressure because we consider that the conventional pneumatic actuator is inadequate for the driving source of a robot hand. First, we examine the characteristics of our new pneumatic actuator. Next, we develop a five-fingered robot hand using this pneumatic actuator. The robot hand produced is both safe and flexible. We construct a master-slave system to enable the robot hand to perform the same operations as a human hand. Next, we make a joint model that has one degree of freedom using a pneumatic actuator. We construct a control system for the joint model and verify its control performance.

  16. Master/slave interferometry – ideal tool for coherence revival swept source optical coherence tomography

    PubMed Central

    Bradu, Adrian; Rivet, Sylvain; Podoleanu, Adrian

    2016-01-01

    In this paper, we demonstrate that the master slave (MS) interferometry method can significantly simplify the practice of coherence revival swept source optical coherence tomography (OCT) technique. Previous implementations of the coherence revival technique required considerable resources on dispersion compensation and data resampling. The total tolerance of the MS method to nonlinear tuning, to dispersion in the interferometer and to dispersion due to the laser cavity, makes the MS ideally suited to the practice of coherence revival. In addition, enhanced versatility is allowed by the MS method in displaying shorter axial range images than that determined by the digital sampling of the data. This brings an immediate improvement in the speed of displaying cross-sectional images at high rates without the need of extra hardware such as graphics processing units or field programmable gate arrays. The long axial range of the coherence revival regime is proven with images of the anterior segment of healthy human volunteers. PMID:27446682

  17. Demography and pathology of an urban slave population from New Orleans.

    PubMed

    Owsley, D W; Orser, C E; Mann, R W; Moore-Jansen, P H; Montgomery, R L

    1987-10-01

    Twenty-nine skeletons from the first cemetery in New Orleans provide significant new information about urban slavery in America. Dating as early as 1720 and used perhaps as late as 1810, the cemetery provided an identifiable sample of two whites, 13 blacks, one individual of possible Indian-white ancestry, and two possibly mulatto individuals. Numerous skeletal and dental lesions were noted in the series, and historical information was used in conjunction with the physical data to draw conclusions about rates and patterns of mortality. Pathological changes indicate that the cemetery contained individuals representing two slave occupational groups, house servants and laborers. This research provides information in the expanding area of Afro-American biohistorical research.

  18. Mott transition in the dynamic Hubbard model within slave boson mean-field approach

    NASA Astrophysics Data System (ADS)

    Le, Duc-Anh

    2014-04-01

    At zero temperature, the Kotliar-Ruckenstein slave boson mean-field approach is applied to the dynamic Hubbard model. In this paper, the influences of the dynamics of the auxiliary boson field on the Mott transition are investigated. At finite boson frequency, the Mott-type features of the Hubbard model is found to be enhanced by increasing the pseudospin coupling parameter g. For sufficiently large pseudospin coupling g, the Mott transition occurs even for modest values of the bare Hubbard interaction U. The lack of electron-hole symmetry is highlighted through the quasiparticle weight. Our results are in good agreement with the ones obtained by two-site dynamical mean-field theory and determinant quantum Monte Carlo simulation.

  19. Reply to ``Comment on `Z2-slave-spin theory for strongly correlated fermions'''

    NASA Astrophysics Data System (ADS)

    Rüegg, Andreas; Huber, Sebastian D.; Sigrist, Manfred

    2013-01-01

    We show that the physical subspace in the Z2-slave-spin theory is conserved under the time evolution of the system. Thus, when restricted to the physical subspace, this representation gives a complete and consistent description of the original problem. In addition, we review two known examples from the existing literature in which the projection onto the physical subspace can be relaxed: (i) the noninteracting limit in any dimension at half-filling and (ii) the interacting model in the infinite-dimensional limit at half-filling. In both cases, physical observables are correctly obtained without explicit treatment of the constraints which define the physical subspace. In these examples, correct results are obtained, despite the fact that unphysical states enter the solution.

  20. Phase-Shift Master-Slave Mechanisms for High Angular-Speed Wedge-Prism Systems

    NASA Astrophysics Data System (ADS)

    Chappuis, Olivier; Clavel, Reymond

    2013-02-01

    Laser micro-machining requires high dynamic laser spot trajectory and accuracy to control the laser beam scanning. A well-known technique to scan a laser beam over a specimen is to use a pair of wedge-prisms. However, it is difficult to master-slave the phase-shift between two rotating prisms at high angular-speed. We present here two drive mechanisms that decouple the phase-shift control and the angular-speed control. These mechanisms simplify the required control architecture and are suitable to achieve a high-dynamic trajectory. These concepts are based on differential timing belts and gears mechanisms that modify the phase-shift between the prisms without interrupting the rotation. This article focuses on the kinematic and mechanical design aspects of such mechanisms.

  1. Dissipative quantum dynamics of fermions in optical lattices: A slave-spin approach

    NASA Astrophysics Data System (ADS)

    Bernier, Jean-Sébastien; Poletti, Dario; Kollath, Corinna

    2014-11-01

    We investigate the influence of a Markovian environment on the dynamics of interacting spinful fermionic atoms in a lattice. To explore the physical phenomena occurring at short times, we develop a method based on a slave-spin representation of fermions that is amenable to the investigation of the dynamics of dissipative systems. We apply this approach to two different dissipative couplings that can occur in current experiments: a coupling via the local density and a coupling via the local double occupancy. We complement our study based on this method, with results obtained using the adiabatic elimination technique and with an exact study of a two-site model. We uncover that the decoherence is slowed down by increasing either the interaction strength or the dissipative coupling (the Zeno effect). We also find, for the coupling to the local double occupancy, that the final steady state can sustain single-particle coherence.

  2. Body burden contaminants in whole fish tissue and livers from the Slave River (NWT)

    SciTech Connect

    McCarthy, L.H.; Stephens, G.R.; Peddle, J.; Lafontaine, C.; Whittle, D.M.; Harbicht, S.

    1995-12-31

    The Slave River Environmental Monitoring Program was established in 1990 to assess whether the commercial and subsistence fisheries in the region were being impacted by downstream transport and subsequent bioaccumulation of contaminants in the fish. Lake whitefish (Coregonus clupeaformis), northern pike (Esox lucius), burbot (Lota lota), walleye (Stizostedion vitreum), and longnose suckers (Catostomus catostomus) were collected in the Slave River at Fort Smith (NWT) and whole fish tissue was evaluated for contaminant accumulation. Due to their high lipid concentration and their importance as food source, burbot livers were also analyzed. A broad organochlorine scan was conducted for selected dioxins and furans, total PCB concentrations and individual congeners, pesticide residues such as DDT and its metabolites, dieldrin, lindane, mirex, and toxaphene. Also, PAHs, and various chlorinated phenolics such as chlorophenols, chlorocatechols, and chloroguaiacols were also examined. Although contaminants were detected in the fish, concentrations generally were minimal. Levels of total PCBs in whole fish tissue ranged from 0.006 to 0.08 mg/kg, while average concentrations in burbot livers were 0.23 mg/kg. The toxic dioxin isomer 2,3,7,8-TCDD was detected once in whole fish tissue (walleye) at levels of 0.86 pg/g, while concentrations in burbot livers ranged from 1.2 to 9.96 pg/g. Higher levels of TCDD (11.4 pg/g) were noted in fish caught at the reference site Chitty/Alexie Lake, although this body of water has no known sources of dioxins and furans. The presence of these compounds indicates a long-range transport and deposition mechanism. Toxaphene concentrations in fish averaged 0.3 mg/kg, while concentrations of p,p{prime}-DDE ranged from 0.001 to 0.008 mg/kg over the monitoring period. Levels of PAHs and chlorinated phenolics were generally below analytical detection limits, as were most of the pesticide residues.

  3. Electrical resistivity structure of the Great Slave Lake shear zone, northwest Canada: implications for tectonic history

    NASA Astrophysics Data System (ADS)

    Yin, Yaotian; Unsworth, Martyn; Liddell, Mitch; Pana, Dinu; Craven, James A.

    2014-10-01

    Three magnetotelluric (MT) profiles in northwestern Canada cross the central and western segments of Great Slave Lake shear zone (GSLsz), a continental scale strike-slip structure active during the Slave-Rae collision in the Proterozoic. Dimensionality analysis indicates that (i) the resistivity structure is approximately 2-D with a geoelectric strike direction close to the dominant geological strike of N45°E and that (ii) electrical anisotropy may be present in the crust beneath the two southernmost profiles. Isotropic and anisotropic 2-D inversion and isotropic 3-D inversions show different resistivity structures on different segments of the shear zone. The GSLsz is imaged as a high resistivity zone (>5000 Ω m) that is at least 20 km wide and extends to a depth of at least 50 km on the northern profile. On the southern two profiles, the resistive zone is confined to the upper crust and pierces an east-dipping crustal conductor. Inversions show that this dipping conductor may be anisotropic, likely caused by conductive materials filling a network of fractures with a preferred spatial orientation. These conductive regions would have been disrupted by strike-slip, ductile deformation on the GSLsz that formed granulite to greenschist facies mylonite belts. The pre-dominantly granulite facies mylonites are resistive and explain why the GSLsz appears as a resistive structure piercing the east-dipping anisotropic layer. The absence of a dipping anisotropic/conductive layer on the northern MT profile, located on the central segment of the GSLsz, is consistent with the lack of subduction at this location as predicted by geological and tectonic models.

  4. Lithalsa distribution, morphology and landscape associations in the Great Slave Lowland, Northwest Territories, Canada

    NASA Astrophysics Data System (ADS)

    Wolfe, Stephen A.; Stevens, Christopher W.; Gaanderse, Adrian J.; Oldenborger, Greg A.

    2014-01-01

    Lithalsas are permafrost mounds formed by ice segregation in mineral-rich soil that occur within the zone of discontinuous permafrost. Nearly 1800 lithalsas were mapped using archival aerial photographs within the Great Slave Lowland, Northwest Territories, Canada. These are up to 8 m high and several hundred meters in length and width. One lithalsa, examined by electrical resistivity and boreholes, rises 4 to 6 m above an adjacent peatland, shows clear evidence of ice-segregation at depth and ground heave of between 2.5 and 4.0 m, and is estimated to have formed within the past 700 years. Regionally, lithalsas are typically located adjacent to ponds and streams with mature forms vegetated by deciduous (birch) forest or mixed (birch and spruce) forest with a herb-shrub understory and include circular, crescentic and linear forms. They are abundant within the Lowland region, which contains widespread glaciolacustrine, lacustrine and alluvial fine-grained sediments. The lithalsas are most common within the first few tens of meters above the present level of Great Slave Lake, indicating that many are late Holocene, and some less than 1000 years, in age. A comparison with lithalsas in contemporary environments reveals that comparatively warm but extensive discontinuous permafrost, fine-grained sediments (alluvial, lacustrine, marine or glaciomarine), and available groundwater supply provide the climatic and hydro-geological parameters for the development of lithalsas in permafrost terrain. The identification of lithalsas in this region is important given their sensitivity to climate change and potential hazards to northern infrastructure upon thawing.

  5. Slave Mode Expansion for Obtaining Ab Initio Interatomic Potentials and its Applications

    NASA Astrophysics Data System (ADS)

    Ai, Xinyuan

    Having an interatomic potential overcomes limitations within DFT since it has a negligible cost in computing material properties while DFT is severely restricted by its computational cost when carrying out such tasks. In this thesis, we propose a new approach for creating an interatomic potential based on the Taylor series expansion of the crystal energy as a function of its nuclear displacements. We enlarge the dimensionality of the existing displacement space and form new variables (ie. slave modes) which transform like irreducible representations of the point group and satisfy homogeneity of free space. Standard group theoretical techniques can then be applied to deduce the non-zero expansion coefficients a priori. At a given order, the translation group can be used to contract the products and eliminate terms which are not linearly independent, resulting in a final set of slave mode products. By the end of the day, one ends up with an expansion that satisfies lattice symmetry and its number of coefficients is much smaller than that of a common Taylor series expansion. While the expansion coefficients can be computed in a variety of ways, we demonstrate that finite difference is effective up to fifth order. On the other hand, we demonstrate the power of the method in the strongly anharmonic systems PbTe and graphene. All anharmonic terms within an octahedron are computed up to fourth order for PbTe, while those within a hexagon are computed up to fourth order and dimer terms are computed at fifth order for graphene. In addition, for PbTe, a proper unitary transformation of its potential demonstrates that the vast majority of the anharmonicity can be attributed to just two terms, indicating that a minimal model of phonon interactions is achievable. The ability to straightforwardly generate polynomial potentials will allow precise simulations at length and time scales which were previously unrealizable.

  6. The Challenge to USAFRICOM from Africa’s Colonial Past

    DTIC Science & Technology

    2010-03-18

    latter part of the 19 th century. Prior to that, Europeans relegated themselves to trading activity primarily along the coast. Arab and African ...merchants managed the business of the slave trade and other goods from the interior of the continent.2 The 1884-1885 Berlin Conference convened...lasted approximately 3 to 4 generations, it, coupled with the slave trade , had long lasting and profound impact upon the indigenous population of the

  7. The Causes of Instability in Nigeria and Implications for the United States

    DTIC Science & Technology

    2013-08-01

    This area was first ruled by the British when Lagos and surround- ing areas were annexed in 1861 to combat the slave trade and formally incorporated...brought about by the slave trade .258 Thus, Nigeria may have always had coherence although, at times, also internal dis- cord.259 Building a sense of...Report on U.S. Trade and Investment Policy Toward Sub-Saharan Africa and Implementation of the African Growth and Opportunity Act. Office of the

  8. Early African Diaspora in colonial Campeche, Mexico: strontium isotopic evidence.

    PubMed

    Price, T Douglas; Tiesler, Vera; Burton, James H

    2006-08-01

    Construction activities around Campeche's central park led to the discovery of an early colonial church and an associated burial ground, in use from the mid-16th century AD to the late 17th century. Remains of some individuals revealed dental mutilations characteristic of West Africa. Analyses of strontium isotopes of dental enamel from these individuals yielded unusually high (87)Sr/(86)Sr ratios, inconsistent with an origin in Mesoamerica, but consistent with an origin in West Africa in terrain underlain by the West Africa Craton, perhaps near the port of Elmina, a principal source of slaves for the New World during the 16th century. These individuals likely represent some of the earliest representatives of the African Diaspora in the Americas.

  9. African Americans' Participation in a Comprehensive Intervention College Prep Program

    ERIC Educational Resources Information Center

    Sianjina, Rayton R.; Phillips, Richard

    2014-01-01

    The National Center for Educational Statistics, in conjunction with the U.S. Department of Education, compiles statistical data for U.S. schools. As charts indicate, in 2001, it reported that nationwide, 76% of high-income graduates immediately enroll in colleges or trade schools. However, only 49% of Hispanic and 59% of African Americans enroll…

  10. Trade in health services.

    PubMed

    Chanda, Rupa

    2002-01-01

    In light of the increasing globalization of the health sector, this article examines ways in which health services can be traded, using the mode-wise characterization of trade defined in the General Agreement on Trade in Services. The trade modes include cross- border delivery of health services via physical and electronic means, and cross-border movement of consumers, professionals, and capital. An examination of the positive and negative implications of trade in health services for equity, efficiency, quality, and access to health care indicates that health services trade has brought mixed benefits and that there is a clear role for policy measures to mitigate the adverse consequences and facilitate the gains. Some policy measures and priority areas for action are outlined, including steps to address the "brain drain"; increasing investment in the health sector and prioritizing this investment better; and promoting linkages between private and public health care services to ensure equity. Data collection, measures, and studies on health services trade all need to be improved, to assess better the magnitude and potential implications of this trade. In this context, the potential costs and benefits of trade in health services are shaped by the underlying structural conditions and existing regulatory, policy, and infrastructure in the health sector. Thus, appropriate policies and safeguard measures are required to take advantage of globalization in health services.

  11. Trade in health services.

    PubMed Central

    Chanda, Rupa

    2002-01-01

    In light of the increasing globalization of the health sector, this article examines ways in which health services can be traded, using the mode-wise characterization of trade defined in the General Agreement on Trade in Services. The trade modes include cross- border delivery of health services via physical and electronic means, and cross-border movement of consumers, professionals, and capital. An examination of the positive and negative implications of trade in health services for equity, efficiency, quality, and access to health care indicates that health services trade has brought mixed benefits and that there is a clear role for policy measures to mitigate the adverse consequences and facilitate the gains. Some policy measures and priority areas for action are outlined, including steps to address the "brain drain"; increasing investment in the health sector and prioritizing this investment better; and promoting linkages between private and public health care services to ensure equity. Data collection, measures, and studies on health services trade all need to be improved, to assess better the magnitude and potential implications of this trade. In this context, the potential costs and benefits of trade in health services are shaped by the underlying structural conditions and existing regulatory, policy, and infrastructure in the health sector. Thus, appropriate policies and safeguard measures are required to take advantage of globalization in health services. PMID:11953795

  12. African Americans and Glaucoma

    MedlinePlus

    ... Involved News About Us Donate In This Section African Americans and Glaucoma email Send this article to a ... glaucoma is the leading cause of blindness in African Americans. Half of those with glaucoma don't know ...

  13. Black African Traditional Mathematics

    ERIC Educational Resources Information Center

    Zaslavsky, Claudia

    1970-01-01

    Discusses the traditional number systems and the origin of the number names used by several African peoples living south of the Sahara. Also included are limitations in African mathematical development, and possible topics for research. (RP)

  14. The impact of African Americans' beliefs about HIV medical care on treatment adherence: a systematic review and recommendations for interventions.

    PubMed

    Gaston, Gina B; Alleyne-Green, Binta

    2013-01-01

    Disparities in access to and retention of regular HIV medical treatment persist among African Americans living with HIV. Many scholars believe that the mistrust of health care held by many African Americans stems from a legacy of abuse, from medical experimentation on slaves to the unethical practices with patients in the Tuskegee Syphilis study. We performed a systematic appraisal of the literature, using several key terms, in order to understand how attitudes about HIV-related health care influence African Americans' engagement in care. We examined peer-reviewed studies published during the period January 2001 through May 2012. An initial search generated 326 studies. Sixteen descriptive studies met our inclusion criteria. Experiences of racism, conspiracy beliefs and the quality of provider relationships appeared to impact engagement. Providers should openly investigate personal beliefs that adversely affect their treatment decisions, listen to patient narratives, and share treatment decisions in order to create a transparent environment.

  15. Breaking the chains: examining the endorsement of modern Jezebel images and racial-ethnic esteem among African American women.

    PubMed

    Brown, Danice L; White-Johnson, Rhonda L; Griffin-Fennell, Felicia D

    2013-01-01

    The historical image of the Black Jezebel - a hypersexual, seductive and manipulative slave woman - has been one of the most pervasive and evolving images influencing the sexual socialization and perceptions of African American women today. This preliminary study examined generational differences in the endorsement of modern depictions of the Jezebel, as well as the relationship between racial-ethnic esteem and endorsement of this sexualised image. A total of 249 African American women completed an online, self-report questionnaire assessing study variables. Results suggested that younger women (aged 18-34) may exhibit higher endorsement of the modern Jezebel depictions. Additionally, aspects of racial-ethnic esteem may be linked to lower endorsement of modern Jezebel depictions among younger and older (55 years and older) African American women. Implications for future research and clinical practice are discussed.

  16. Biological trade and markets.

    PubMed

    Hammerstein, Peter; Noë, Ronald

    2016-02-05

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

  17. Biological trade and markets

    PubMed Central

    2016-01-01

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other ‘commodities’. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten ‘terms of contract’ that ‘self-stabilize’ trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models—often called ‘Walrasian’ markets—are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying ‘principal–agent’ problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists

  18. The African Connection

    ERIC Educational Resources Information Center

    Oguntoyinbo, Lekan

    2012-01-01

    From student and faculty exchanges to joint research projects, U.S. universities maintain a broad spectrum of collaborative relationships with African universities. It's unclear how many U.S. colleges and universities have partnerships with African universities. The African Studies Association, an organization of scholars, doesn't keep that kind…

  19. The development of medical museums in the antebellum American South: slave bodies in networks of anatomical exchange.

    PubMed

    Kenny, Stephen C

    2013-01-01

    Prior to the American Civil War, museums were enthusiastically promoted in the annual circulars of southern medical colleges as valuable aids to medical education. Using case history narratives, medical college circulars, and announcements, this article examines the social origins of the region's collections of anatomical and pathological specimens and explores the professional agents and organizations responsible for their maintenance and development. The article is also concerned with exploring the racial framework in which these bodies and specimens were sourced and displayed. The social relations embodied in natural history and medical museum collections, and the emerging specialism of "negro medicine," were all elements of a context that subordinated and objectified blackness, as well as permitting and legitimizing the exploitation of black bodies. Medical museums function as a key case study for examining power relations among physicians, slaves, and slave owners, as well as underscoring southern medicine's dependence on slavery for its development.

  20. Concealment of time delay signature of chaotic output in a slave semiconductor laser with chaos laser injection

    NASA Astrophysics Data System (ADS)

    Wu, Tianan; Sun, Weiyang; Zhang, Xiaoxu; Zhang, Shenghai

    2016-12-01

    An improved chaotic laser system, which has a slave semiconductor laser (SL) injected by a master SL with double optical feedback (DOF), is proposed, so that the time delay (TD) signature can be successfully concealed from both intensity and phase chaos via choosing appropriate parameters. The TD signature is investigated by employing autocorrelation function (ACF) and mutual information (MI) function. Through analyzing the influence on TD signature in the region of injection current and injection strength for the slave SL, we find that, for both intensity chaos and phase chaos, the TD signature can be easily concealed under weak injection strength. When the injection strength is strong, we can not only successfully conceal TD signature, but also improve the bandwidth of chaotic laser output by choosing the optimal detuning frequency.

  1. Little Known Facts about Yesterday's Impact on Today's Speech.

    ERIC Educational Resources Information Center

    Williamson, Juanita V.; Thompson, C. Lamar

    Two major theories trace the origins of black English to African influence or British Isles influence. According to the African origin theory, black English was created through pidginization, creolization, and decreolization as Africans came into contact with Europeans through the slave trade. The second theory holds that most black English…

  2. Slave-boson mean-field theory versus variational-wave-function approach for the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Yang, Min-Fong; Sun, Shih-Jye; Hong, Tzay-Ming

    1993-12-01

    We show that a special kind of slave-boson mean-field approximation, which allows for the symmetry-broken states appropriate for a bipartite lattice, can give essentially the same results as those by the variational-wave-function approach proposed by Gula´csi, Strack, and Vollhardt [Phys. Rev. B 47, 8594 (1993)]. The advantages of our approach are briefly discussed.

  3. International trade. Multinational aspects.

    PubMed

    Ozawa, Y

    2000-01-01

    Of numerous regional economic agreements, the European Union (EU), the North American Free Trade Agreement (NAFTA), South American Common Market (MERCOSUR), the Association of Southeast Asian Nations (ASEAN), the South Asian Association for Regional Cooperation (SAARC) and the Australia-New Zealand Closer Economic Relations Agreement are examples that are actively pursuing regional integration for freer trade of animals and animal products. The World Trade Organization (WTO) believes that regional and multinational integration initiatives are complements rather than alternatives in the pursuit of more open trade. In the efforts to harmonize SPS standards among multilateral trading nations, it is recommended that national requirements meet the standards developed by the OIE and the FAO/WHO Codex Alimentarius Commission as the minimum requirements rather than adopting the standards of the lowest common denominator. Regional grouping may hinder multilateral or bilateral trade between the countries of a group and those of the other groups. How to eliminate such non-tariff barriers as traditional trade custom remains to be examined. Ongoing activities of VICH (Harmonisation of Technical Requirements for Registration of Veterinary Medical Products) may pave the way for more open trade in pharmaceutical products between multilateral regional groups.

  4. Free Trade: A Misnomer?

    ERIC Educational Resources Information Center

    McMillan, Robert R.

    1983-01-01

    Billions of dollars are lost each year in our balance of payments because U.S. multinationals have not entered foreign markets due to trade restrictions and restrictions on the remittance of profits and royalties. Formal and informal government obstructions to free trade are examined. (RM)

  5. Introduction to International Trade.

    ERIC Educational Resources Information Center

    Intercom, 1986

    1986-01-01

    Focusing mainly on United States-Japan relations, this issue provides 11 lesson plans and student handouts dealing with international trade topics such as protective tariffs, currency exchange rates, unofficial trade barriers, causes of unemployment, the balance of payments and the internationalization of the automobile industry. (JDH)

  6. Leveraging master-slave OpenFlow controller arrangement to improve control plane resiliency in SD-EONs.

    PubMed

    Chen, Xiaoliang; Zhao, Bin; Ma, Shoujiang; Chen, Cen; Hu, Daoyun; Zhou, Wenshuang; Zhu, Zuqing

    2015-03-23

    In this paper, we study how to improve the control plane resiliency of software-defined elastic optical networks (SD-EONs) and design a master-slave OpenFlow (OF) controller arrangement. Specifically, we introduce two OF controllers (OF-Cs), i.e., the master and slave OF-Cs, and make them work in a collaborative way to protect the SD-EON against controller failures. We develop a controller communication protocol (CCP) to facilitate the cooperation of the two OF-Cs. With the CCP, the master OF-C (M-OF-C) can synchronize network status to the slave OF-C (S-OF-C) in real time, while S-OF-C can quickly detect the failure of M-OF-C and take over the network control and management (NC&M) tasks timely to avoid service disruption. We implement the proposed framework in an SD-EON control plane testbed built with high-performance servers, and perform NC&M experiments with different network failure scenarios to demonstrate its effectiveness. Experimental results indicate that the proposed system can restore services in both the data and control planes of SD-EON jointly while maintaining relatively good scalability. To the best of our knowledge, this is the first demonstration that realizes control plane resiliency in SD-EONs.

  7. A Passive Parallel Master-Slave Mechanism for Magnetic Resonance Imaging-Guided Interventions.

    PubMed

    Elayaperumal, Santhi; Cutkosky, Mark R; Renaud, Pierre; Daniel, Bruce L

    2015-03-01

    A passive, parallel master-slave mechanism is presented for magnetic resonance imaging (MRI)-guided interventions in the pelvis. The mechanism allows a physician to stand outside the MRI scanner while manipulating a needle inside the bore and, unlike a powered robot, does not place actuators in proximity to the patient. The manipulator combines two parallel mechanisms based on the Delta robot architecture. The mechanism also includes a two-axis gimbal to allow for tool angulation, giving a total of five degrees of freedom so that the physician can insert and steer a needle using continuous natural arm and wrist movements, unlike simple needle guides. The need for access between the patient's legs and within the MRI scanner leads to an unusual asymmetric design in which the sliding prismatic joints form the vertices of an isosceles triangle. Kinematic analysis shows that the dexterity index of this design is improved over the desired workspace, as compared to an equilateral design. The analysis is extended to estimate the effect of friction and model the input:output force transmission. Prototypes, with final dimensions selected for transperineal prostate interventions, showed force transmission behavior as predicted by simulation, and easily withstood maximum forces required for tool insertion.

  8. Ligand recombination and a hierarchy of solvent slaved dynamics: the origin of kinetic phases in hemeproteins.

    PubMed

    Samuni, Uri; Dantsker, David; Roche, Camille J; Friedman, Joel M

    2007-08-15

    Ligand recombination studies play a central role both for characterizing different hemeproteins and their conformational states but also for probing fundamental biophysical processes. Consequently, there is great importance to providing a foundation from which one can understand the physical processes that give rise to and modulate the large range of kinetic patterns associated with ligand recombination in myoglobins and hemoglobins. In this work, an overview of cryogenic and solution phase recombination phenomena for COMb is first reviewed and then a new paradigm is presented for analyzing the temperature and viscosity dependent features of kinetic traces in terms of multiple phases that reflect which tier(s) of solvent slaved protein dynamics is (are) operative on the photoproduct population during the time course of the measurement. This approach allows for facile inclusion of both ligand diffusion among accessible cavities and conformational relaxation effects. The concepts are illustrated using kinetic traces and MEM populations derived from the CO recombination process for wild type and mutant myoglobins either in sol-gel matrices bathed in glycerol or in trehalose-derived glassy matrices.

  9. Master/slave optical coherence tomography imaging of eyelid basal cell carcinoma.

    PubMed

    Chin, Catherine; Bradu, Adrian; Lim, Rongxuan; Khandwala, Mona; Schofield, John; Leick, Lasse; Podoleanu, Adrian

    2016-09-10

    Optical coherence tomography (OCT) is fast emerging as an additional non-interventional modality for skin tumor detection and diagnosis. A master/slave flying spot OCT configuration was assembled to detect periocular basal cell carcinomas (BCC). A swept source at 1300 nm and sweeping speed of 50 kHz were used. A three-step process was involved. First, 384 channeled spectra using a mirror were stored for 384 optical path differences at the master stage. Then, the stored channeled spectra (masks) were correlated with the channeled spectrum from the BCC tissue to produce 384 en face OCT images (200×200 pixels) for the optical path difference values used to acquire the masks. Finally, these en face slices were stacked to form a volume to cross-reference BCC tumor margins in the orthogonal plane. Per each eyelid sample, several en face images of 200×200 lateral pixels are produced in the time to scan laterally a complete raster of 1.6 s. Combination of the en face views with the cross-sectioning views allow for better discrimination of BCCs comparable to using cross-sectional imaging alone, as previously reported using the conventional fast-Fourier-transform-based OCT techniques.

  10. Oxidation state of the lithospheric mantle beneath Diavik diamond mine, central Slave craton, NWT, Canada

    NASA Astrophysics Data System (ADS)

    Creighton, Steven; Stachel, Thomas; Eichenberg, Dave; Luth, Robert W.

    2010-05-01

    Oxygen fugacity ( fO2) conditions were determined for 29 peridotite xenoliths from the A154-North and A154-South kimberlites of the Diavik diamond mine using the newly developed flank method modified specifically for measuring Fe3+ in mantle-derived pyropic garnets. The results indicate that the garnet-bearing lithospheric mantle beneath the central Slave craton is vertically layered with respect to oxidation state. The shallow (<140 km), “ultra-depleted” layer is the most oxidized section of garnet-bearing subcratonic mantle thus far measured, up to one log unit more oxidizing relative to the FMQ buffer [Δlog fO2 (FMQ) + 1]. The lower, more fertile layer has fO2 conditions that extend down to Δlog fO2 (FMQ) - 3.8, consistent with xenolith suites from other localities worldwide. Based on trace element concentrations in garnets, two distinct metasomatic events affected the mantle lithosphere at Diavik. An oxidized fluid imparted sinusoidal chondrite-normalized REE patterns on garnets throughout the entire depth range sampled. In contrast, a reducing melt metasomatic event affected only the lower portion of the lithospheric mantle. The fO2 state of the Diavik mantle sample suggests that diamond formation occurred by reduction of carbonate by fluids arising from beneath the lithosphere.

  11. A slave cluster expansion for obtaining ab-initio interatomic potentials

    NASA Astrophysics Data System (ADS)

    Ai, Xinyuan; Marianetti, Chris

    2014-03-01

    Here we propose a new approach for performing a Taylor series expansion of the first-principles computed energy of a crystal as a function of the nuclear displacements. We enlarge the dimensionality of the existing displacement space and form new variables (i.e. slave clusters) which transform like irreducible representations of the point group and satisfy homogeneity of free space. Standard group theoretical techniques can then be applied to deduce the non-zero expansion coefficients apriori at a given order, and the translation group can be used to contract the products and eliminate terms which are not linearly independent. While the expansion coefficients could likely be computed in a variety of ways, we demonstrate that finite difference is effective up to fourth order. We demonstrate the power of the method in the strongly anharmonic system PbTe. All anharmonic terms within an octahedron are computed up to fourth order. A proper linear transform demonstrates that the vast majority of the anharmonicity can be attributed to just two terms, indicating that a minimal model of phonon interactions is achievable. The ability to straightforwardly generate polynomial potentials will allow precise simulations at length and time scales which were previously unrealizable.

  12. 19 CFR 10.178a - Special duty-free treatment for sub-Saharan African countries.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Special duty-free treatment for sub-Saharan... for sub-Saharan African countries. (a) General. Section 506A of the Trade Act of 1974 (19 U.S.C. 2466a... eligible beneficiary sub-Saharan African country for purposes of that duty-free treatment. (b)...

  13. Level of environmental threat posed by horticultural trade in Cactaceae.

    PubMed

    Novoa, Ana; Le Roux, Johannes J; Richardson, David M; Wilson, John R U

    2017-01-11

    Ornamental horticulture has been identified as an important threat to plant biodiversity and the major pathway for plant invasions worldwide. In this context, the family Cactaceae is particularly interesting and challenging for three main reasons-it is considered the fifth most threatened major taxonomic group in the world; several cactus species are amongst the most widespread and damaging invasive species; and Cactaceae is one of the most popular horticultural plant groups. Based on CITES trade data and the eleven main auction sites selling cacti on the internet we document a substantial global trade from and to almost all continents. While less than 20 % of this trade involves threatened species, and less than 3% involves known invasive species, many species are sold without a valid scientific name. Importantly, however, hardly any of the globally traded cacti are collected from wild populations. In order to provide an in-depth look at the dynamics of the industry, we surveyed the businesses involved in the cactus trade in South Africa (one of the main hotspots of cactus trade and invasions). Despite a large commercial network, all South African imports (of which only 15 % and 1.5 % were of species listed as threatened and invasive, respectively) came from the same source. We purchased seeds of every available species and, based on DNA-barcoding techniques, could only identify 24 % of the species to genus level. If trade restrictions are placed on the small proportion of cacti that are invasive and there is no major increase in harvesting of native populations, the commercial cactus horticultural trade will pose a negligible environmental threat. However, there are currently no effective methods for easily identifying which cacti are traded, and both the illicit harvesting of cacti from the wild and the informal trade in invasive taxa pose on-going conservation challenges. This article is protected by copyright. All rights reserved.

  14. Intellectual Property Rights and Access to Medicines: International Trade Issues

    DTIC Science & Technology

    2009-05-28

    for pharmaceutical companies to invest in R&D. • Type III diseases, such as dengue fever and African sleeping sickness, are those that have...customs authorities temporarily halted shipments of generic medicines manufactured in India and in transit to Colombia and Peru via the Netherlands... Peru , Panama, and Colombia. The Obama Administration is reviewing U.S. trade policy, including IPRs and pharmaceuticals

  15. Library - Book Trade Relations

    ERIC Educational Resources Information Center

    Tuttle, Helen Welch

    1970-01-01

    The trend in relations between the library and the book trade has been in the direction of increased communication and cooperation. Organizational links between librarians, publishers, and booksellers are discussed. (Author/JS)

  16. A Good Trade.

    ERIC Educational Resources Information Center

    Thiers, Naomi

    1996-01-01

    Describes education and training needs, numbers employed, and salary scales for the following skilled trades: glaziers, painters/paperhangers, sheetmetal workers, insulation workers, bricklayers, stonemasons, carpenters, electricians, plumbers/pipefitters, and welders. (SK)

  17. Environment, Trade, and Investment

    EPA Pesticide Factsheets

    Environment, trade, and investment are fundamentally linked as the environment provides many basic inputs of economic activity – forests, fisheries, metals, minerals – as well as the energy used to process those materials.

  18. What Is Emissions Trading?

    EPA Pesticide Factsheets

    Learn the basics about how emissions trading uses a market-based policy tool used to control large amounts of pollution emissions from a group of sources in order to protect human health and the environment.

  19. Training European Trade Unionists.

    ERIC Educational Resources Information Center

    Miller, Doug; Stirling, John

    1998-01-01

    A study of trade union education in Germany, Italy, Sweden, and the United Kingdom finds training is being adapted to meet new political and economic conditions. Significant national differences appeared in terms of legislation, funding, training, and accreditation. (SK)

  20. Trading forest carbon - OSU

    EPA Science Inventory

    Issues associate with trading carbon sequestered in forests are discussed. Scientific uncertainties associated with carbon measurement are discussed with respect to proposed accounting procedures. Major issues include: (1) Establishing baselines. (2) Determining additivity from f...

  1. Mantle melts, metasomatism and diamond formation: Insights from melt inclusions in xenoliths from Diavik, Slave Craton

    NASA Astrophysics Data System (ADS)

    Araújo, D. P.; Griffin, W. L.; O'Reilly, S. Y.

    2009-11-01

    Abundant carbonatitic to ultramafic melt inclusions 0.2-2.5mm in diameter occur in the Cr-diopside of megacrystalline lherzolite xenoliths from the A154 kimberlite of the Diavik mine, Lac de Gras area. The melts range from carbonatitic (50-97% carbonate) to Ca-Mg-silicic (10-50% carbonate) to Mg-silicic (< 10% dispersed calcite) compositions, and are connected by veinlets of similar material, or by fractures bordered by spongy Cr-diopside. Phenocrysts and quench crystals of calcite, olivine and mica are set in carbonatitic to Mg-silicic matrices, and irregular volumes of carbonatite and Mg-silicate melt appear to have unmixed from one another within single inclusions. Calculated bulk compositions of the more silicic melts are similar in major- and trace elements to kimberlites from the Slave province. The Cr-diopside adjacent to melt inclusions is enriched in LREE, Ba, alkali elements, HFSE, Th and U. Calculated compositions of the metasomatising fluids are strongly enriched in these elements relative to the trapped melts, and are similar to fluids trapped in the opaque coats found on many Diavik diamonds. The microstructures, the metasomatic effects and the genetic relationship to diamond formation suggest that the melt inclusions formed when kimberlite-like melts penetrated the lherzolites along fractures deep in the lithospheric mantle. The melts began to differentiate into carbonatitic and ultramafic end-members, were trapped as globular inclusions during recrystallisation and necking-down prior to entrainment of the xenoliths in the kimberlite, and were quenched during ascent. The evolution of saline, water- and carbonate-rich fluids from melts such as these may play an important role in diamond genesis.

  2. Livestock policy and trade issues in SADC.

    PubMed

    Hulman, B

    2009-03-01

    As from 2001, the Southern African Development Community (SADC) has embarked on a course to deepen regional integration through restructuring. Under the new structure SADC has centralised the coordination of its activities to the Secretariat in Gaborone. The former Sector Coordinating Units have been merged into four directorates, one of which is the Food, Agriculture and Natural Resources (FANR) Directorate, which comprises, amongst others, the Livestock Development Unit (LDU). The LDU, under the aegis of the FANR, formulates policies for regional livestock development in order to respond to the objectives of the Regional Indicative Strategic Development Plan (RISDP), and which are mainly to: Contribute to improved food security, Promote wealth creation, Enhance rural livelihood, Enhance livestock as a tradable and consumable commodity. Following the launch of the SADC Economic Partnership Agreement (EPA) negotiations, the eight SADC EPA member states identified sanitary and phytosanitary and technical barriers to trade to be major trade barriers for access to international markets, especially the EU market where standards are normally set beyond international standards. SADC has already brought some of the issues related to beef exports to the OIE Regional Commission for Africa as SADC member states feel that a few of the present requirements do not have a scientific basis. The paper discusses the process that the LDU follows in the formulation of policies and strategies in regional livestock development with the objective of bolstering intra and extra regional trade in livestock and livestock products.

  3. Trade, TRIPS, and pharmaceuticals.

    PubMed

    Smith, Richard D; Correa, Carlos; Oh, Cecilia

    2009-02-21

    The World Trade Organization's Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) set global minimum standards for the protection of intellectual property, substantially increasing and expanding intellectual-property rights, and generated clear gains for the pharmaceutical industry and the developed world. The question of whether TRIPS generates gains for developing countries, in the form of increased exports, is addressed in this paper through consideration of the importance of pharmaceuticals in health-care trade, outlining the essential requirements, implications, and issues related to TRIPS, and TRIPS-plus, in which increased restrictions are imposed as part of bilateral free-trade agreements. TRIPS has not generated substantial gains for developing countries, but has further increased pharmaceutical trade in developed countries. The unequal trade between developed and developing countries (ie, exporting and importing high-value patented drugs, respectively) raises the issue of access to medicines, which is exacerbated by TRIPS-plus provisions, although many countries have not even enacted provision for TRIPS flexibilities. Therefore this paper focuses on options that are available to the health community for negotiation to their advantage under TRIPS, and within the presence of TRIPS-plus.

  4. Physicians and Insider Trading.

    PubMed

    Kesselheim, Aaron S; Sinha, Michael S; Joffe, Steven

    2015-12-01

    Although insider trading is illegal, recent high-profile cases have involved physicians and scientists who are part of corporate governance or who have access to information about clinical trials of investigational products. Insider trading occurs when a person in possession of information that might affect the share price of a company's stock uses that information to buy or sell securities--or supplies that information to others who buy or sell--when the person is expected to keep such information confidential. The input that physicians and scientists provide to business leaders can serve legitimate social functions, but insider trading threatens to undermine any positive outcomes of these relationships. We review insider-trading rules and consider approaches to securities fraud in the health care field. Given the magnitude of the potential financial rewards, the ease of concealing illegal conduct, and the absence of identifiable victims, the temptation for physicians and scientists to engage in insider trading will always be present. Minimizing the occurrence of insider trading will require robust education, strictly enforced contractual provisions, and selective prohibitions against high-risk conduct, such as participation in expert consulting networks and online physician forums, by those individuals with access to valuable inside information.

  5. African swine fever: an epidemiological update.

    PubMed

    Sánchez-Vizcaíno, J M; Mur, L; Martínez-López, B

    2012-03-01

    African swine fever (ASF) is one of the most important swine diseases, mainly because of its significant sanitary and socioeconomic consequences. This review gives an update on the epidemiology of the disease and reviews key issues and strategies to improve control of the disease and promote its eradication. Several characteristics of ASF virus (ASFV) make its control and eradication difficult, including the absence of available vaccines, marked virus resistance in infected material and contaminated animal products, and a complex epidemiology and transmission involving tick reservoir virus interactions. The incidence of ASF has not only increased on the African continent over the last 15 years, so that it now affects West African countries, Mauritius and Madagascar, but it has also reached new areas, such as the Caucasus region in 2007. In fact, the rapid spread of the disease on the European continent and the uncontrolled situation in the Russian Federation places all countries at great risk as a result of intense global trade. The proximity of some affected areas to the European Union (EU) borders (<150 km) has increased concerns about the potential economic consequences of an ASF incursion into the EU pig sector. Establishing effective surveillance, control and eradication programmes that implicate all actors (veterinarians, farmers, and policy makers) is essential for controlling ASF. African swine fever -free countries should be aware of the potential risk of ASF incursion and implement risk reduction measures such as trade controls and other sanitary measures. This review will discuss lessons learnt so far about ASF control, current challenges to its control and future studies needed to support global efforts at prevention and control.

  6. China in Africa: America’s Soft Power Challenge

    DTIC Science & Technology

    2011-05-01

    involved in the African slave trade and supported South African government during the Apartheid era in the 1980s to secure precious metals. The...relationships with African leaders is to exploit the unfortunate aspects of African history , most notably slavery and colonialism, and emphasize the post...military and during crises. The general perception for China, however, is that Africans and Chinese share similar histories and they are there to

  7. The African superswell

    NASA Technical Reports Server (NTRS)

    Nyblade, Andrew A.; Robinson, Scott W.

    1994-01-01

    Maps of residual bathymetry in the ocean basins around the African continent reveal a broad bathymetric swell in the southeastern Atlantic Ocean with an amplitude of about 500 m. We propose that this region of anomalously shallow bathymetry, together with the contiguous eastern and southern African plateaus, form a superswell which we refer to as the African superswell. The origin of the African superswell is uncertain. However, rifting and volcanism in eastern Africa, as well as heat flow measurements in southern Africa and the southeastern Atlantic Ocean, suggest that the superswell may be attributed, at least in part, to heating of the lithosphere.

  8. Intention-Disguised Algorithmic Trading

    NASA Astrophysics Data System (ADS)

    Yuen, William; Syverson, Paul; Liu, Zhenming; Thorpe, Christopher

    Large market participants (LMPs) must often execute trades while keeping their intentions secret. Sometimes secrecy is required before trades are completed to prevent other traders from anticipating (and exploiting) the price impact of their trades. This is known as "front-running". In other cases, LMPs with proprietary trading strategies wish to keep their positions secret even after trading because their strategies and positions contain valuable information. LMPs include hedge funds, mutual funds, and other specialized market players.

  9. Phanerozoic deposition, erosion, and vertical motion history of the Slave craton from apatite (U-Th)/He thermochronometry

    NASA Astrophysics Data System (ADS)

    Ault, A. K.; Flowers, R. M.; Bowring, S. A.

    2012-12-01

    Resolving the history and causes of elevation change in cratonic settings is a challenging problem. We integrate apatite (U-Th)/He thermochronometry (AHe) data and geologic observations to constrain the Phanerozoic burial, unroofing, and hypsometric evolution of the Archean Slave craton and surrounding Proterozoic belts in the northwestern Canadian shield. Although the craton currently lacks Phanerozoic strata, Phanerozoic sedimentary xenoliths contained within kimberlites of different ages demonstrate that such rocks once covered the craton. The thermochronometry data allow us to constrain the spatial extent, thickness, and history of these now-denuded sedimentary units. New AHe results consist of 94 apatite analyses for 16 samples and, together with previously published data, yield one of the largest published cratonic AHe datasets. AHe dates range from 210 ± 12 Ma to 363 ± 37 Ma. Dates are older in the eastern Slave craton and decrease to the west. Thermal history simulations are consistent with Paleozoic heating to temperatures ≥88-90 °C, suggesting burial beneath ≥3.5 km of sedimentary rocks across the region, followed by cooling and unroofing that progressed from east to west. Model results also permit heating in Cretaceous time, consistent with burial to ≤1.3 km and subsequent unroofing. When combined with other AHe datasets, regional unconformities, and sedimentary xenolith data, the results show that an episode of Paleozoic-early Mesozoic burial and unroofing affected most of the western Canadian shield. This history is out of sequence with sea level chronologies and demands Paleozoic subsidence of the craton followed by surface uplift. The Slave craton subsequently underwent at least 300 m of post-100 Ma elevation gain, based on ca. 100 Ma marine sedimentary xenoliths entrained in ~75-45 Ma kimberlites of the central Slave craton at modern 500-600 m elevations. Comparison of this hypsometric history with far-field plate boundary activity suggests

  10. Single-frequency, injection-seeded Er:YAG laser based on a bow-tie ring slave resonator

    NASA Astrophysics Data System (ADS)

    Yao, B. Q.; Deng, Yu; Dai, T. Y.; Duan, X. M.; You-Lun, Ju; Wang, Y. Z.

    2015-08-01

    A diode pumped, injection-seeded Q-switched Er:YAG laser at 1645.2 nm is demonstrated. A single frequency Er:YAG monolithic nonplanar ring oscillator (NPRO) laser emitting at 1645.24 nm with a maximum output power of 500 mW is used as a seed laser. The seed laser output is injected into a bow-tie slave laser, obtaining stable single-frequency Q-switched operation of the Er:YAG laser. The maximum single-frequency Q-switched Er:YAG laser output energy is 2.9 mJ at 100 Hz with a pulse duration of 160 ns.

  11. Do host species evolve a specific response to slave-making ants?

    PubMed Central

    2012-01-01

    Background Social parasitism is an important selective pressure for social insect species. It is particularly the case for the hosts of dulotic (so called slave-making) ants, which pillage the brood of host colonies to increase the worker force of their own colony. Such raids can have an important impact on the fitness of the host nest. An arms race which can lead to geographic variation in host defenses is thus expected between hosts and parasites. In this study we tested whether the presence of a social parasite (the dulotic ant Myrmoxenus ravouxi) within an ant community correlated with a specific behavioral defense strategy of local host or non-host populations of Temnothorax ants. Social recognition often leads to more or less pronounced agonistic interactions between non-nestmates ants. Here, we monitored agonistic behaviors to assess whether ants discriminate social parasites from other ants. It is now well-known that ants essentially rely on cuticular hydrocarbons to discriminate nestmates from aliens. If host species have evolved a specific recognition mechanism for their parasite, we hypothesize that the differences in behavioral responses would not be fully explained simply by quantitative dissimilarity in cuticular hydrocarbon profiles, but should also involve a qualitative response due to the detection of particular compounds. We scaled the behavioral results according to the quantitative chemical distance between host and parasite colonies to test this hypothesis. Results Cuticular hydrocarbon profiles were distinct between species, but host species did not show a clearly higher aggression rate towards the parasite than toward non-parasite intruders, unless the degree of response was scaled by the chemical distance between intruders and recipient colonies. By doing so, we show that workers of the host and of a non-host species in the parasitized site displayed more agonistic behaviors (bites and ejections) towards parasite than toward non

  12. Understanding African American Males

    ERIC Educational Resources Information Center

    Bell, Edward Earl

    2010-01-01

    The purpose of this study was to assess the socialization skills, self-esteem, and academic readiness of African American males in a school environment. Discussions with students and the School Perceptions Questionnaire provided data for this investigation. The intended targets for this investigation were African American students; however, there…

  13. Educating African American Males

    ERIC Educational Resources Information Center

    Bell, Edward E.

    2010-01-01

    Background: Schools across America spend money, invest in programs, and sponsor workshops, offer teacher incentives, raise accountability standards, and even evoke the name of Obama in efforts to raise the academic achievement of African American males. Incarceration and college retention rates point to a dismal plight for many African American…

  14. 16 Extraordinary African Americans.

    ERIC Educational Resources Information Center

    Lobb, Nancy

    This collection for children tells the stories of 16 African Americans who helped make America what it is today. African Americans can take pride in the heritage of these contributors to society. Biographies are given for the following: (1) Sojourner Truth, preacher and abolitionist; (2) Frederick Douglass, abolitionist; (3) Harriet Tubman, leader…

  15. Keeping African Masks Real

    ERIC Educational Resources Information Center

    Waddington, Susan

    2012-01-01

    Art is a good place to learn about our multicultural planet, and African masks are prized throughout the world as powerfully expressive artistic images. Unfortunately, multicultural education, especially for young children, can perpetuate stereotypes. Masks taken out of context lose their meaning and the term "African masks" suggests that there is…

  16. Global Trade and Public Health

    PubMed Central

    Shaffer, Ellen R.; Waitzkin, Howard; Brenner, Joseph; Jasso-Aguilar, Rebeca

    2005-01-01

    Global trade and international trade agreements have transformed the capacity of governments to monitor and to protect public health, to regulate occupational and environmental health conditions and food products, and to ensure affordable access to medications. Proposals under negotiation for the World Trade Organization’s General Agreement on Trade in Services (GATS) and the regional Free Trade Area of the Americas (FTAA) agreement cover a wide range of health services, health facilities, clinician licensing, water and sanitation services, and tobacco and alcohol distribution services. Public health professionals and organizations rarely participate in trade negotiations or in resolution of trade disputes. The linkages among global trade, international trade agreements, and public health deserve more attention than they have received to date. PMID:15623854

  17. Global trade and public health.

    PubMed

    Shaffer, Ellen R; Waitzkin, Howard; Brenner, Joseph; Jasso-Aguilar, Rebeca

    2005-01-01

    Global trade and international trade agreements have transformed the capacity of governments to monitor and to protect public health, to regulate occupational and environmental health conditions and food products, and to ensure affordable access to medications. Proposals under negotiation for the World Trade Organization's General Agreement on Trade in Services (GATS) and the regional Free Trade Area of the Americas (FTAA) agreement cover a wide range of health services, health facilities, clinician licensing, water and sanitation services, and tobacco and alcohol distribution services. Public health professionals and organizations rarely participate in trade negotiations or in resolution of trade disputes. The linkages among global trade, international trade agreements, and public health deserve more attention than they have received to date.

  18. Heart motion uncertainty compensation prediction method for robot assisted beating heart surgery - Master-slave Kalman Filters approach.

    PubMed

    Liang, Fan; Yu, Yang; Cui, Shigang; Zhao, Li; Wu, Xingli

    2014-05-01

    Robot Assisted Coronary Artery Bypass Graft (CABG) allows the heart keep beating in the surgery by actively eliminating the relative motion between point of interest (POI) on the heart surface and surgical tool. The inherited nonlinear and diverse nature of beating heart motion gives a huge obstacle for the robot to meet the demanding tracking control requirements. In this paper, we novelty propose a Master-slave Kalman Filter based on beating heart motion Nonlinear Adaptive Prediction (NAP) algorithm. In the study, we describe the beating heart motion as the combination of nonlinearity relating mathematics part and uncertainty relating non-mathematics part. Specifically, first, we model the nonlinearity of the heart motion via quadratic modulated sinusoids and estimate it by a Master Kalman Filter. Second, we involve the uncertainty heart motion by adaptively change the covariance of the process noise through the slave Kalman Filter. We conduct comparative experiments to evaluate the proposed approach with four distinguished datasets. The results indicate that the new approach reduces prediction errors by at least 30 μm. Moreover, the new approach performs well in robustness test, in which two kinds of arrhythmia datasets from MIT-BIH arrhythmia database are assessed.

  19. Master-slave interferometry for parallel spectral domain interferometry sensing and versatile 3D optical coherence tomography.

    PubMed

    Podoleanu, Adrian Gh; Bradu, Adrian

    2013-08-12

    Conventional spectral domain interferometry (SDI) methods suffer from the need of data linearization. When applied to optical coherence tomography (OCT), conventional SDI methods are limited in their 3D capability, as they cannot deliver direct en-face cuts. Here we introduce a novel SDI method, which eliminates these disadvantages. We denote this method as Master - Slave Interferometry (MSI), because a signal is acquired by a slave interferometer for an optical path difference (OPD) value determined by a master interferometer. The MSI method radically changes the main building block of an SDI sensor and of a spectral domain OCT set-up. The serially provided signal in conventional technology is replaced by multiple signals, a signal for each OPD point in the object investigated. This opens novel avenues in parallel sensing and in parallelization of signal processing in 3D-OCT, with applications in high- resolution medical imaging and microscopy investigation of biosamples. Eliminating the need of linearization leads to lower cost OCT systems and opens potential avenues in increasing the speed of production of en-face OCT images in comparison with conventional SDI.

  20. [The Pharaohs: slave merchants or organizers of an efficient welfare system? Re-writing history through new documentation and research].

    PubMed

    Melino, C; Del Vecchio, R; Druda, L

    2003-01-01

    The Authors have studied documents dating from the era of the Pharaohs, that is to say: the papyruses of Ebers and Smith, and have come to the conclusion that the recent claims by some archaeologists that the Egyptian workmen who built the Pyramids, were protected by health regulations and not treated as slaves, is true. This is a new interpretation of Egyptian history, because up to now, it has always been thought that the workmen were slaves. The construction of the Pharaoh's tomb was a team work including members of the upper classes (architects, physicians) and the lower classes (masons, workmen) and was the demonstration of a contribution and a symbol of recognition from all members of the team to the head of the society (the Pharaoh), who was their employer and took their interests into consideration e.g. health regulations. The Authors have also deduced from other sources of information that a public health system and welfare organization, comparable to our present day Legislative Decree 626/94, did in fact exist in the ancient world.

  1. The Tipping Point of Robotic Surgery In Healthcare: From Master-Slave to Flexible Access Bio-Inspired Platforms.

    PubMed

    Athanasiou, Thanos; Ashrafian, Hutan; Rao, Christopher; Yang, Guang-Zhong; Darzi, Ara

    2011-12-01

    Surgical robots were introduced to overcome the technical issues of limited operative dexterity and inadequate visualization in complex body areas. Current surgical robotic systems are based on a master-slave relationship in which the master-surgeon provides operative guidance for the slave-robot to perform operative tasks. Robotic operations are most frequently applied in urology (primarily focusing on prostatectomy) and cardiac surgery. The evolution of surgical robotics has made significant strides in the past decade. There are, however, some limitatio0The future of robotic surgery promises several augmentations to provide improvements in surgical visualization, somatosensory perception, and enhanced robot-surgeon interactions. These can be achieved through advances in robotic research and academic healthcare leadership to develop the next generation of surgical robots such as the novel flexible access bio-inspired (FAB) platforms. The drive to move toward ever less-invasive and safer procedures while maintaining high-quality treatment outcomes has maintained the momentum of progress since the initial birth of minimally invasive surgery, so that robotic surgery can be increasingly applied in a wider range of healthcare settings.

  2. Neotropical Africanized honey bees have African mitochondrial DNA.

    PubMed

    Smith, D R; Taylor, O R; Brown, W M

    1989-05-18

    Non-indigenous African honey bees have invaded most of South and Central America in just over 30 years. The genetic composition of this population and the means by which it rapidly colonizes new territory remain controversial. In particular, it has been unclear whether this 'Africanized' population has resulted from interbreeding between African and domestic European bees, or is an essentially pure African population. Also, it has not been known whether this population expanded primarily by female or by male migration. Restriction site mapping of 62 mitochondrial DNAs of African bees from Brazil, Venezuela and Mexico reveals that 97% were of African (Apis mellifera scutellata) type. Although neotropical European apiary populations are rapidly Africanized by mating with neotropical African males, there is little reciprocal gene flow to the neotropical African population through European females. These are the first genetic data to indicate that the neotropical African population could be expanding its range by female migration.

  3. Construction Trades Resources.

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education, Juneau. Div. of Adult and Vocational Education.

    This guide was developed as a supplement to the Alaska Department of Education's Construction Trades Curriculum. The special topics included in it focus on competencies from the curriculum for which materials were not readily available to Alaskan teachers and provide information that is either required by Alaska's environmental conditions or is…

  4. Trading forest carbon

    EPA Science Inventory

    The nature of carbon in forests is discussed from the perspective of carbon trading. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Carbon turnover in forests is discussed as it relates to carbon sequestration. Scient...

  5. Learning with Trade Unionists.

    ERIC Educational Resources Information Center

    Wooton, Richard

    1986-01-01

    Recommends that the study of trade unions be included in the school curriculum. Argues that learning about relationships between unions and management through interviews, observations, and simulations can enhance the overall approach to teaching about controversial topics. Gives examples of some attempts to do this in schools. (TW)

  6. Trade-Secret Dispute.

    ERIC Educational Resources Information Center

    Blumenstyk, Goldie

    1994-01-01

    A Michigan court has ruled that a Wayne State University (Michigan) chemistry professor appropriated a trade secret from a Massachusetts chemist for whom he was consulting and incorporated it into his own patent application, violating a written agreement. The university contends its pursuit of the patent was not improper. (MSE)

  7. Recreational Vehicle Trades.

    ERIC Educational Resources Information Center

    Felice, Michael

    This curriculum guide provides materials for a competency-based course in recreational vehicle trades at the secondary level. The curriculum design uses the curriculum infused model for the teaching of basic skills as part of vocational education and demonstrates the relationship of vocationally related skills to communication, mathematics, and…

  8. Learn a Trade

    ERIC Educational Resources Information Center

    Crawford, Matthew B.

    2015-01-01

    The author earned a physics degree in college and then failed to find a job in the aerospace industry. He writes of how he fell back on his training as an electrician for sustenance and from that extrapolates how the trades have become confused with work of the hands rather than of the mind. He uses the venerable debate between Booker T.…

  9. Modern Maritime Trade Warfare

    DTIC Science & Technology

    2013-05-20

    intergovernmental organizations impose both immediate and long term penalties for an enemy. Finally, tools such as cyber attacks and GPS spoofing ...Exclusion Zones to interfere with shipping networks, and GPS jamming or spoofing of merchant vessels are discussed and analyzed for potential...SUBJECT TERMS Maritime Trade Warfare, Commerce Warfare, China, Cyber, GPS , Jamming, Spoofing , Maritime Interdiction, Exclusion Zone. 16. SECURITY

  10. Trade Masonry Syllabus.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Occupational Education Curriculum Development.

    Designed for a two-year course of study, this syllabus encompasses six areas of the masonry trade: concrete, block, brick, stone, tile, and plaster. For each area, the separate units of instruction contain course content outline, student behavioral objectives, and suggested teaching methods and audiovisuals. The six sections and their units are as…

  11. Introduction to International Trade.

    ERIC Educational Resources Information Center

    Crummett, Dan M.; Crummett, Jerrie

    This set of student and teacher guides is intended for use in a course to prepare students for entry-level employment in such occupational areas in international trade as business/finance, communications, logistics, and marketing. The following topics are covered in the course's five instructional units: introduction to careers in international…

  12. Syllabus in Trade Welding.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

    The syllabus outlines material for a course two academic years in length (minimum two and one-half hours daily experience) leading to entry-level occupational ability in several welding trade areas. Fourteen units covering are welding, gas welding, oxyacetylene welding, cutting, nonfusion processes, inert gas shielded-arc welding, welding cast…

  13. Construction Trades Curriculum.

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education, Juneau. Div. of Adult and Vocational Education.

    This competency-based curriculum is designed to be a handbook for the construction trades. It includes all competencies a student will acquire in the course of building a complete house. Based on a survey of Alaskan construction employers and employees, the handbook stresses both principles and skills. The 23 units are presented in the sequence…

  14. NEEDLE TRADES, MATHEMATICS - I.

    ERIC Educational Resources Information Center

    COLICCHIO, ANTOINETTE J.

    THE NEEDLE TRADES INDUSTRY CONSISTS OF THREE TYPES OF ESTABLISHMENTS -- THE REGULAR MANUFACTURERS, THE APPAREL JOBBERS, AND THE CONTRACTORS. THE FUNCTIONS INCLUDED COVER A WIDE SCOPE FROM BUYING OF RAW MATERIAL TO SELLING OF THE FINISHED APPAREL. THE PURPOSE OF THIS STUDY GUIDE IS TO FURNISH BASIC KNOWLEDGE IN MATHEMATICS AND DEVELOP SKILL IN…

  15. Trade Union Rights.

    ERIC Educational Resources Information Center

    Maier, Heribert; And Others

    1994-01-01

    Excerpts addresses from an international symposium regarding workers' education, human rights, labor standards and law, socioeconomic factors, trade unions, workers' rights, professionalism, and globalization. Includes a background paper, "Participation of Workers and Their Organizations in the Field of International Labour Standards and the…

  16. Maintenance Trades Guidelines

    ERIC Educational Resources Information Center

    Weidner, Theodore J.

    2008-01-01

    In 2002, APPA published "Maintenance Staffing Guidelines for Educational Facilities," the first building maintenance trades staffing guideline designed to assist educational facilities professionals with their staffing needs. addresses how facilities professionals can determine the appropriate size and mix of their organization. Contents…

  17. Machine Trades Curriculum Guide. Michigan Trade and Industrial Education.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide is intended to help secondary teachers provide relevant training for an entry-level job in machine trades. Introductory materials include background information on trade and industrial education and program goals and safety information. Descriptions follow of the construction trades program, vocational cooperative…

  18. Trading Network Predicts Stock Price

    PubMed Central

    Sun, Xiao-Qian; Shen, Hua-Wei; Cheng, Xue-Qi

    2014-01-01

    Stock price prediction is an important and challenging problem for studying financial markets. Existing studies are mainly based on the time series of stock price or the operation performance of listed company. In this paper, we propose to predict stock price based on investors' trading behavior. For each stock, we characterize the daily trading relationship among its investors using a trading network. We then classify the nodes of trading network into three roles according to their connectivity pattern. Strong Granger causality is found between stock price and trading relationship indices, i.e., the fraction of trading relationship among nodes with different roles. We further predict stock price by incorporating these trading relationship indices into a neural network based on time series of stock price. Experimental results on 51 stocks in two Chinese Stock Exchanges demonstrate the accuracy of stock price prediction is significantly improved by the inclusion of trading relationship indices. PMID:24429767

  19. Trading Network Predicts Stock Price

    NASA Astrophysics Data System (ADS)

    Sun, Xiao-Qian; Shen, Hua-Wei; Cheng, Xue-Qi

    2014-01-01

    Stock price prediction is an important and challenging problem for studying financial markets. Existing studies are mainly based on the time series of stock price or the operation performance of listed company. In this paper, we propose to predict stock price based on investors' trading behavior. For each stock, we characterize the daily trading relationship among its investors using a trading network. We then classify the nodes of trading network into three roles according to their connectivity pattern. Strong Granger causality is found between stock price and trading relationship indices, i.e., the fraction of trading relationship among nodes with different roles. We further predict stock price by incorporating these trading relationship indices into a neural network based on time series of stock price. Experimental results on 51 stocks in two Chinese Stock Exchanges demonstrate the accuracy of stock price prediction is significantly improved by the inclusion of trading relationship indices.

  20. Spatial distribution of kimberlite in the Slave craton, Canada: a geometrical approach

    NASA Astrophysics Data System (ADS)

    Stubley, M. P.

    2004-09-01

    Exploration within the Slave craton has revealed clusters of kimberlite intrusions, commonly with internally consistent geochemical and temporal characteristics. Translation diagrams ("Fry analysis") allow an unbiased geometrical examination of the distance and direction between each kimberlite occurrence and all others in the database. Recurrent patterns are visually accentuated due to the square function in data density. Circular histograms quantify the azimuthal density of kimberlite at various distances. For this study, the database comprises the geographic position of 212 kimberlite occurrences of which 70% are from the Lac de Gras field (LDG). Analyses are presented separately for the LDG data and for all non-LDG data in order to test for regional variations and to avoid overwhelming the craton-scale studies by the high density of LDG data. Empirical grouping of kimberlite locations results in delineation of five elliptical clusters that encompass all but four kimberlite occurrences. Clusters within the western part of the craton are elongate to the north-northeast and align within a narrow zone ("Western Corridor"). Elsewhere, the clusters are elongate to the northwest or west-northwest and appear to be arranged en echelon within a poorly defined north-northwest trending zone ("Central Corridor"). Geometrical spatial analyses of kimberlite locations highlight the craton-scale pattern of emplacement within the two main corridors. At regional and local scales, individual intrusions are preferentially located towards the west-northwest (ca. 280°) and north-northeast (ca. 015°) of other intrusions, and these orientations are interpreted to reflect upper mantle trends in magma generation. At local scales (10-25 km), kimberlite of the central and southern craton tends to be located to the northeast (ca. 045°), and possibly weakly to the east-northeast (ca. 070°), of other intrusions, and these orientations correspond to major crustal fractures systems. It is

  1. A twentieth-century triangle trade: selling black beauty at home and abroad, 1945–1965.

    PubMed

    McAndrew, Malia

    2010-01-01

    This study examines the careers of African American beauty culturists as they worked in the United States, Europe, and Africa between 1945 and 1965. Facing push back at home, African American beauty entrepreneurs frequently sought out international venues that were hospitable and receptive to black Americans in the years following World War II. By strategically using European sites that white Americans regarded as the birthplace of Western fashion and beauty, African American entrepreneurs in the fields of modeling, fashion design, and hair care were able to win accolades and advance their careers. In gaining support abroad, particularly in Europe, these beauty culturists capitalized on their international success to establish, legitimize, and promote their business ventures in the United States. After importing a positive reputation for themselves from Europe to the United States, African American beauty entrepreneurs then exported an image of themselves as the world's premier authorities on black beauty to people of color around the globe as they sold their products and marketed their expertise on the African continent itself. This essay demonstrates the important role that these black female beauty culturists played, both as businesspeople and as race leaders, in their generation's struggle to gain greater respect and opportunity for African Americans both at home and abroad. In doing so it places African American beauty culturists within the framework of transatlantic trade networks, the Black Freedom Movement, Pan-Africanism, and America's Cold War struggle.

  2. The Shotgun or the Schoolhouse? Optimal Strategy to Achieve Canadian Policy Objectives in Africa

    DTIC Science & Technology

    2011-12-01

    community has stifled trade and limited the functioning of viable African economies. The social situation in Africa ranges from the peace and stability of... African country, be it North Africa or Sub- Saharan Africa. 13 The Standing Senate Committee on Foreign Affairs and International Trade , Overcoming 40...task, and the UK’s colonial past in Sierra Leone. The UK and Sierra Leone have a relationship that extends back to Britain’s slave - trading days

  3. South Carolina Trade Examinations Handbook.

    ERIC Educational Resources Information Center

    Crook, Shirley J.

    The South Carolina Trade Examinations for Trade and Industrial Education teachers are administered semi-annually by the South Carolina State Department of Education, Office of Vocational Education, Vocational Teacher Education Programs Unit. This handbook is designed to provide prospective trade and industrial education teachers, vocational…

  4. African American Suicide

    MedlinePlus

    ... accounted for 83.8% of Caucasian elderly suicides. • Firearms were the predominant method of suicide among African ... per 100,000 annually. Source: Centers for Disease Control and Prevention. National Vital Statistics System. Mortality Data. ...

  5. Obesity and African Americans

    MedlinePlus

    ... and Management System Report to Congress Knowledge Center Capacity Building Information Services Events Calendar Resource Guide Justice ... Workforce Diversity Grants Youth Program Grants Other Grants Planning and Evaluation Grantee Best Practices Black/African American ...

  6. Texts of Our Institutional Lives. "Don't You Mean "Slaves," Not "Servants"?": Literary and Institutional Texts for an Interdisciplinary Classroom

    ERIC Educational Resources Information Center

    Ashton, Susanna

    2006-01-01

    The author describes an undergraduate course she taught on "Representations of Slavery." In particular, she explains how the course involved studying an historic site on her university's campus: the former slave plantation of leading antebellum racist John C. Calhoun. She also analyzes how her school represents the site on its Web pages. (Contains…

  7. Late Archean greenstone tectonics: Evidence for thermal and thrust-loading lithospheric subsidence from stratigraphic sections in the Slave Province, Canada

    NASA Technical Reports Server (NTRS)

    Kidd, W. S. F.; Kusky, T. M.; Bradley, D. C.

    1988-01-01

    How late Archean tectonics could be seen to have operated in the Slave Province is illustrated. Lithospheric thinning and stretching, with the formation of rifted margins (to continental or island arc fragments), and lithospheric flexural loading of the kind familiar in arcs and mountain belts could be discerned.

  8. Emergency China Trade Act

    THOMAS, 112th Congress

    Rep. Sherman, Brad [D-CA-27

    2011-09-13

    09/19/2011 Referred for a period ending not later than September 19, 2011, (or for a later time if the Chairman so designates) to the Subcommittee on Trade, in each case for consideration of such provisions as fall within the jurisdiction of the subcommittee concerned. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  9. Trade Remedies: A Primer

    DTIC Science & Technology

    2008-07-30

    Developing nations, such as India and South Africa , had begun using trade remedy actions more frequently, whereas they were tools used almost exclusively...CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING...group of products are minerals and metals (such as brass sheet and strip; gray portland cement and clinker ; magnesium). The fourth largest group

  10. LDCM Preliminary Thermal Trades

    NASA Technical Reports Server (NTRS)

    Ryan, Robert; Pagnutti, Mary; Blonski, Slawomir; Spruce, Joe

    2001-01-01

    The expected cost of adding thermal bands to the next generation Landsat Data Continuity Mission (LDCM) could be significant. This viewgraph presentation investigates both traditional cooled cross-track scanners and new architectures (cooled and uncooled) which could enable a low cost thermal capability. The presentation includes surveys of applications of Landsat thermal data and the architecture of thermal instruments. It also covers new thermal architecture sensor trades, ALI Architecture with Uncooled TIR Detectors, and simulated thermal imagery.

  11. Does trade affect child health?

    PubMed

    Levine, David I; Rothman, Dov

    2006-05-01

    Frankel and Romer [Frankel, J., Romer, D., 1999. Does trade cause growth? American Economic Review 89 (3), 379-399] documented positive effects of geographically determined trade openness on economic growth. At the same time, critics fear that openness can lead to a "race to the bottom" that increases pollution and reduces government resources for investments in health and education. We use Frankel and Romer's gravity model of trade to examine how openness to trade affects children. Overall, we find little harm from trade, and potential benefits largely through slightly faster GDP growth.

  12. International Trade of Biofuels (Brochure)

    SciTech Connect

    Not Available

    2013-05-01

    In recent years, the production and trade of biofuels has increased to meet global demand for renewable fuels. Ethanol and biodiesel contribute much of this trade because they are the most established biofuels. Their growth has been aided through a variety of policies, especially in the European Union, Brazil, and the United States, but ethanol trade and production have faced more targeted policies and tariffs than biodiesel. This fact sheet contains a summary of the trade of biofuels among nations, including historical data on production, consumption, and trade.

  13. Inter-Industry Trade and Intra-Industry Trade: Some Recent Developments in International Trade Theory.

    ERIC Educational Resources Information Center

    Greenaway, David

    1978-01-01

    Contends that the analysis of intra-industry trade supplements the subject of trade theory in undergraduate economics courses. Intra-industry trade is the situation in which a country both exports and imports the products of a particular industry, e.g. automobiles. Questions for discussion are included. (KC)

  14. A review of the evolution and trajectory of the African union as an instrument of regional integration.

    PubMed

    Chirisa, Innocent Ew; Mumba, Artwell; Dirwai, Simbarashe O

    2014-01-01

    This review paper seeks to analyse African integration in terms of its magnitude of solidarity, the state and typology of integration and functioning. It assesses the strengths, weaknesses, objectives, successes and failures of the African integration project as well as threats to its survival. The primary goal is to sift between issues with the view of better informing the future of the integration. The paper acknowledges how, in 2002, the OAU (formed in 1963) convened to reconstitute and become the African Union (AU) composed of eight Regional Economic Communities. The reformed union has spelt out gender equality, strategic planning, intra-trade, non-indifference to suffering in member states and sustainability, as additional objectives to those of the former OAU. This idea has been to foster integration to promote peace, security and cooperation hence solidarity. It can now be assessed succinctly that African integration has arisen in the need for amalgamation of efforts to solve African problems with African solutions.

  15. Single-frequency, injection-seeded Er:YAG laser based on a bow-tie ring slave resonator

    SciTech Connect

    Yao, B Q; Deng, Yu; Dai, T Y; Duan, X M; Ju You-Lun; Wang, Y Z

    2015-08-31

    A diode pumped, injection-seeded Q-switched Er:YAG laser at 1645.2 nm is demonstrated. A single frequency Er:YAG monolithic nonplanar ring oscillator (NPRO) laser emitting at 1645.24 nm with a maximum output power of 500 mW is used as a seed laser. The seed laser output is injected into a bow-tie slave laser, obtaining stable single-frequency Q-switched operation of the Er:YAG laser. The maximum single-frequency Q-switched Er:YAG laser output energy is 2.9 mJ at 100 Hz with a pulse duration of 160 ns. (lasers)

  16. A distortion correction algorithm for fish-eye panoramic image of master-slave visual surveillance system

    NASA Astrophysics Data System (ADS)

    Zuo, Chenglin; Liu, Yu; Li, Yongle; Xu, Wei; Zhang, Maojun

    2013-09-01

    A master-slave visual surveillance system is composed of one fish-eye panoramic camera and one dynamic pan-tilt-zoom (PTZ) dome camera. In order to make PTZ dome camera zoom into all targets of interest in panoramic image, the fish-eye panoramic camera is fixed inclining towards the gravity direction, which may cause more obvious distortion. This paper proposed a novel method for the distortion correction of captured panoramic image based on the midpoint circle algorithm (MCA). The method uses incremental calculation of decision parameters to determine the pixel positions along a circle circumference, and both of the vertical and horizontal are rectilinearised. Experimental results show that our correction method based on MCA is efficient and effective. In particular, due to its low computational cost, our method can be applied on embedded camera platform without any extra hardware resources.

  17. Summer foods of American widgeon, mallards, and a green-winged teal near Great Slave Lake, N.W.T

    USGS Publications Warehouse

    Bartonek, J.C.

    1972-01-01

    Foods found in three species of dabbling ducks collected during summer from bog ponds, and sedge pools in taiga on the north side of Great Slave Lake, Northwest Territories, are described. Animal material in the esophageal contents of 10 adult American Widgeons (Mareca americana) averaged 31 i?? 34 per cent (P<0.05) by volume. A significantly higher percentage of animal material was found in Class I and II widgeon ducklings (66 i?? 22 per cent) than in Class IIIa ducklings and flying juveniles (12 i?? 20 per cent) of this species. Animal material comprised 87 i?? 35 per cent of esophageal contents from five Class II and flying juvenile Mallards (Anas platyrhynchos) and 100 per cent of that from an adult female Green-winged Teal (A. carolinensis).

  18. International red meat trade.

    PubMed

    Brester, Gary W; Marsh, John M; Plain, Ronald L

    2003-07-01

    The maturation of the US beef and pork markets and increasing consumer demands for convenience, safety, and nutrition suggests that the beef and pork industries must focus on product development and promotion. New marketing arrangements are developing that help coordinate production with consumer demands. The relative high levels of incomes in the United States are likely to increase the demands for branded products rather than increase total per capita consumption. Foreign markets represent the greatest opportunity for increased demand for commodity beef and pork products. Increasing incomes in developing countries will likely allow consumers to increase consumption of animal-source proteins. Real prices of beef and pork have declined substantially because of sagging domestic demand and increasing farm-level production technologies. Increasing US beef and pork exports have obviated some of the price declines. Pork attained a net export position from a quantity perspective in 1995. The United States continues to be a net importer of beef on a quantity basis but is close to becoming a net exporter in terms of value. By-products continue to play a critical role in determining the red meat trade balance and producer prices. The United States, however, must continue to become cost, price, and quality competitive with other suppliers and must secure additional market access if it is to sustain recent trade trends. Several trade tensions remain in the red meat industry. For example, mandated COOL will undoubtedly have domestic and international effects on the beef and pork sectors. Domestically, uncertainty regarding consumer demand responses or quality perceptions regarding product origin, as well as added processor-retailer costs will be nontrivial. How these factors balance out in terms of benefits versus costs to the industry is uncertain. From an international perspective, some beef and pork export suppliers to the United States could view required labeling as a

  19. Water in the Cratonic Mantle: Insights from FTIR Data on Lac De Gras Xenoliths (Slave Craton, Canada)

    NASA Technical Reports Server (NTRS)

    Peslier, Anne H.; Brandon, Alan D.; Schaffer, Lillian Aurora; O'Reilly, Suzanne Yvette; Griffin, William L.; Morris, Richard V.; Graff, Trevor G.; Agresti, David G.

    2014-01-01

    The mantle lithosphere beneath the cratonic part of continents is the deepest (> 200 km) and oldest (>2-3 Ga) on Earth, remaining a conundrum as to how these cratonic roots could have resisted delamination by asthenospheric convection over time. Water, or trace H incorporated in mineral defects, could be a key player in the evolution of continental lithosphere because it influences melting and rheology of the mantle. Mantle xenoliths from the Lac de Gras kimberlite in the Slave craton were analyzed by FTIR. The cratonic mantle beneath Lac de Gras is stratified with shallow (<145 km) oxidized ultradepleted peridotites and pyroxenites with evidence for carbonatitic metasomatism, underlain by reduced and less depleted peridotites metasomatized by kimberlite melts. Peridotites analyzed so far have H O contents in ppm weight of 7-100 in their olivines, 58 to 255 in their orthopyroxenes (opx), 11 to 84 in their garnet, and 139 in one clinopyroxene. A pyroxenite contains 58 ppm H2O in opx and 5 ppm H2O in its olivine and garnet. Olivine and garnet from the deep peridotites have a range of water contents extending to higher values than those from the shallow ones. The FTIR spectra of olivines from the shallow samples have more prominent Group II OH bands compared to the olivines from the deep samples, consistent with a more oxidized mantle environment. The range of olivine water content is similar to that observed in Kaapvaal craton peridotites at the same depths (129-184 km) but does not extend to as high values as those from Udachnaya (Siberian craton). The Slave, Kaapvaal and Siberian cratons will be compared in terms of water content distribution, controls and role in cratonic root longevity.

  20. Polychlorinated biphenyl concentrations of burbot Lota lota from Great Slave Lake are very low but vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Stapanian, Martin A.; Cott, Peter A.; Rediske, Richard R.; O'Keefe, James P.

    2014-01-01

    Total polychlorinated biphenyl concentrations (ΣPCBs) in whole fish were determined for 18 ripe female burbot Lota lota and 14 ripe male burbot from Great Slave Lake, a lake with no known point sources of PCBs. In addition, ΣPCBs were determined both in the somatic tissue and in the gonads for a randomly selected subset of five females and five males. Mean ΣPCBs for females and males were 2.89 and 3.76 ng/g, respectively. Thus, males were 30 % greater in ΣPCB than females. Based on ΣPCB determinations for somatic tissue and gonads, ΣPCBs of females and males would be expected to decrease by 18 % and increase by 6 %, respectively, immediately after spawning due to release of gametes. Results from a previous study in eastern Lake Erie indicated that males were 28 and 71 % greater in ΣPCB than females from populations of younger (ages 6-13) and older (ages 14-17) burbot, respectively. Thus, although younger burbot from Lake Erie were about 50 times greater in ΣPCB than Great Slave Lake burbot, the relative difference in ΣPCBs between the sexes was remarkably similar across both populations. Our results supported the contention that the widening of the difference in ΣPCBs between the sexes in older burbot from Lake Erie was attributable to a “hot spot” effect operating on older burbot, as Lake Erie has received PCB point source loadings. Our results also supported the contention that male fish expend energy at a rate between 15 and 30 % greater than that of females. Eventually, these results will be useful in developing sex-specific bioenergetics models for fish.

  1. A novel manipulation method of human body ownership using an fMRI-compatible master-slave system.

    PubMed

    Hara, Masayuki; Salomon, Roy; van der Zwaag, Wietske; Kober, Tobias; Rognini, Giulio; Nabae, Hiroyuki; Yamamoto, Akio; Blanke, Olaf; Higuchi, Toshiro

    2014-09-30

    Bodily self-consciousness has become an important topic in cognitive neuroscience aiming to understand how the brain creates a unified sensation of the self in a body. Specifically, full body illusion (FBI) in which changes in bodily self-consciousness are experimentally introduced by using visual-tactile stimulation has led to improve understanding of these mechanisms. This paper introduces a novel approach to the classic FBI paradigm using a robotic master-slave system which allows us to examine interactions between action and the sense of body ownership in behavioral and MRI experiments. In the proposed approach, the use of the robotic master-slave system enables unique stimulation in which experimental participants can administer tactile cues on their own back using active self-touch. This active self-touch has never been employed in FBI experiments and it allows to test the role of sensorimotor integration and agency (the feeling of control over our actions) in FBI paradigms. The objective of this study is to propose a robotic-haptic platform allowing a new FBI paradigm including the active self-touch in MRI environments. This paper, first, describes the design concept and the performance of the prototype device in the fMRI environment (for 3T and 7T MRI scanners). In addition, the prototype device is applied to a classic FBI experiment, and we verify that the use of the prototype device succeeded in inducing the FBI. These results indicate that the proposed approach has a potential to drive advances in our understanding of human body ownership and agency by allowing novel manipulation and paradigms.

  2. Low birth weight of contemporary African Americans: an intergenerational effect of slavery?

    PubMed

    Jasienska, Grazyna

    2009-01-01

    The average birth weight in the contemporary African-American population is about 250 g lower than the average birth weight of European Americans. Differences in genetic and socioeconomic factors present between these two groups can explain only part of birth weight variation. I propose a hypothesis that the low birth weight of contemporary African Americans not only results from the difference in present exposure to lifestyle factors known to affect fetal development but also from conditions experienced during the period of slavery. Slaves had poor nutritional status during all stages of life because of the inadequate dietary intake accompanied by high energetic costs of physical work and infectious diseases. The concept of "fetal programming" suggests that physiology and metabolism including growth and fat accumulation of the developing fetus, and, thus its birth weight, depend on intergenerational signal of environmental quality passed through generations of matrilinear ancestors. I suggest that several generations that have passed since the abolition of slavery in the United States (1865) has not been enough to obliterate the impact of slavery on the current biological and health condition of the African-American population.

  3. Glucose intolerance in the West African Diaspora: a skeletal muscle fibre type distribution hypothesis.

    PubMed

    Nielsen, J; Christensen, D L

    2011-08-01

    In the United States, Black Americans are largely descendants of West African slaves; they have a higher relative proportion of obesity and experience a higher prevalence of diabetes than White Americans. However, obesity rates alone cannot explain the higher prevalence of type 2 diabetes. Type 2 diabetes is characterized by insulin resistance and beta-cell dysfunction. We hypothesize that the higher prevalence of type 2 diabetes in African Americans (as compared to White Americans) is facilitated by an inherited higher percentage of skeletal muscle fibre type II and a lower percentage of skeletal muscle fibre type I. Skeletal muscle fibre type II is less oxidative and more glycolytic than skeletal muscle fibre type I. Lower oxidative capacity is associated with lower fat oxidation and a higher disposal of lipids, which are stored as muscular adipose tissue in higher amounts in Black compared to White Americans. In physically active individuals, the influence of muscle fibre composition will not be as detrimental as in physically inactive individuals. This discrepancy is caused by the plasticity in the skeletal muscle fibre characteristics towards a higher activity of oxidative enzymes as a consequence of physical activity. We suggest that a higher percentage of skeletal muscle fibre type II combined with physical inactivity has an impact on insulin sensitivity and high prevalence of type 2 diabetes in Blacks of West African ancestry.

  4. Coccidioidomycosis in African Americans

    PubMed Central

    Ruddy, Barbara E.; Mayer, Anita P.; Ko, Marcia G.; Labonte, Helene R.; Borovansky, Jill A.; Boroff, Erika S.; Blair, Janis E.

    2011-01-01

    Coccidioidomycosis is caused by Coccidioides species, a fungus endemic to the desert regions of the southwestern United States, and is of particular concern for African Americans. We performed a PubMed search of the English-language medical literature on coccidioidomycosis in African Americans and summarized the pertinent literature. Search terms were coccidioidomycosis, Coccidioides, race, ethnicity, African, black, and Negro. The proceedings of the national and international coccidioidomycosis symposia were searched. All relevant articles and their cited references were reviewed; those with epidemiological, immunologic, clinical, and therapeutic data pertaining to coccidioidomycosis in African Americans were included in the review. Numerous studies documented an increased predilection for severe coccidioidal infections, coccidioidomycosis-related hospitalizations, and extrapulmonary dissemination in persons of African descent; however, most of the published studies are variably problematic. The immunologic mechanism for this predilection is unclear. The clinical features and treatment recommendations are summarized. Medical practitioners need to be alert to the possibility of coccidioidomycosis in persons with recent travel to or residence in an area where the disease is endemic. PMID:21193657

  5. 17 CFR 37.400 - Core Principle 4-Monitoring of trading and trade processing.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... trading and trade processing. 37.400 Section 37.400 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SWAP EXECUTION FACILITIES Monitoring of Trading and Trade Processing § 37.400 Core Principle 4—Monitoring of trading and trade processing. The swap execution facility shall: (a) Establish...

  6. Geographic variation of stable isotopes in African elephant ivory

    NASA Astrophysics Data System (ADS)

    Ziegler, S.; Merker, S.; Jacob, D.

    2012-04-01

    In 1989, the international community listed the African elephant in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) thus prohibiting commercial ivory trade. Recent surveillance data show that the illegal trade in ivory has been growing worldwide. Long-term preservation of many of the African elephant populations can be supported with a control mechanism that helps with the implementation of remedial conservation action. Therefore, setting up a reference database that predicts the origin of ivory specimens can assist in determining smuggling routes and the provenance of illegal ivory. Our research builds on earlier work to seek an appropriate method for determining the area of origin for individual tusks. Several researchers have shown that the provenance of elephant ivory can be traced by its isotopic composition, but this is the first attempt to produce an integrated isotopic reference database of elephant ivory provenance. We applied a combination of various routine geochemical analyses to measure the stable isotope ratios of hydrogen, carbon, nitrogen, oxygen, and sulphur. Up to now, we analysed 606 ivory samples of known geographical origin from African range states, museums and private collections, comprising 22 African elephant range states. The isotopic measurements were superimposed with data layers from vegetation, geology and climate. A regression function for the isotope composition of the water isotopes in precipitation and collagen in ivory was developed to overcome the problem of imprecise origin of some of the sampled material. Multivariate statistics, such as nearest neighborhood and discriminate analysis were applied to eventually allow a statistical determination of the provenance for ivory of unknown origin. Our results suggest that the combination of isotopic parameters have the potential to provide predictable and complementary markers for estimating the origin of seized elephant ivory.

  7. Mental Health and African Americans

    MedlinePlus

    ... Minority Population Profiles > Black/African American > Mental Health Mental Health and African Americans Poverty level affects mental health ... compared to 120% of non-Hispanic whites. 1 MENTAL HEALTH STATUS Serious psychological distress among adults 18 years ...

  8. Trade policy and public health.

    PubMed

    Friel, Sharon; Hattersley, Libby; Townsend, Ruth

    2015-03-18

    Twenty-first-century trade policy is complex and affects society and population health in direct and indirect ways. Without doubt, trade policy influences the distribution of power, money, and resources between and within countries, which in turn affects the natural environment; people's daily living conditions; and the local availability, quality, affordability, and desirability of products (e.g., food, tobacco, alcohol, and health care); it also affects individuals' enjoyment of the highest attainable standard of health. In this article, we provide an overview of the modern global trade environment, illustrate the pathways between trade and health, and explore the emerging twenty-first-century trade policy landscape and its implications for health and health equity. We conclude with a call for more interdisciplinary research that embraces complexity theory and systems science as well as the political economy of health and that includes monitoring and evaluation of the impact of trade agreements on health.

  9. Fair trade international surrogacy.

    PubMed

    Humbyrd, Casey

    2009-12-01

    Since the development of assisted reproductive technologies, infertile individuals have crossed borders to obtain treatments unavailable or unaffordable in their own country. Recent media coverage has focused on the outsourcing of surrogacy to developing countries, where the cost for surrogacy is significantly less than the equivalent cost in a more developed country. This paper discusses the ethical arguments against international surrogacy. The major opposition viewpoints can be broadly divided into arguments about welfare, commodification and exploitation. It is argued that the only valid objection to international surrogacy is that surrogate mothers may be exploited by being given too little compensation. However, the possibility of exploitation is a weak argument for prohibition, as employment alternatives for potential surrogate mothers may be more exploitative or more harmful than surrogacy. It is concluded that international surrogacy must be regulated, and the proposed regulatory mechanism is termed Fair Trade Surrogacy. The guidelines of Fair Trade Surrogacy focus on minimizing potential harms to all parties and ensuring fair compensation for surrogate mothers.

  10. The Struggles over African Languages

    ERIC Educational Resources Information Center

    Maseko, Pam; Vale, Peter

    2016-01-01

    In this interview, African Language expert Pam Maseko speaks of her own background and her first encounter with culture outside of her mother tongue, isiXhosa. A statistical breakdown of South African languages is provided as background. She discusses Western (originally missionary) codification of African languages and suggests that this approach…

  11. Final Report: African Power/Energy and Environmental Development Plan, July 1, 1994 - August 21, 1999

    SciTech Connect

    Butler, John M.

    1999-08-21

    In 1994 AEF signed a Cooperative Agreement with DOE to address a program called the African Power /Energy and Environmental Development Plan. The Program initially addressed five area: (1) Historical Black Colleges and Universities Energy/Environmental Program; (2) The Department of Energy and United States Private Industry Africa Program; (3) The Annual United States Energy Study Tour; (4) South African Training Program, and (5) South African Environmental Program. The programs were implemented in conjunction with DOE, institutions, agencies and the private sector support in the USA and within African nations. AEF has worked with government and technical representatives from 13 African nations and expanded the program to address sponsorship of South African students in Historical Black Colleges and Universities, supporting DOE trade missions through participation and planning, and giving presentations in the U.S., and Africa regarding business opportunities in the African energy sector. The programs implemented have also opened doors for the US private sector to seek business opportunities in Africa and for African nations to gain exposure to US products and services.

  12. Narcolepsy in African Americans

    PubMed Central

    Kawai, Makoto; O'Hara, Ruth; Einen, Mali; Lin, Ling; Mignot, Emmanuel

    2015-01-01

    Study Objectives: Although narcolepsy affects 0.02–0.05% of individuals in various ethnic groups, clinical presentation in different ethnicities has never been fully characterized. Our goal was to study phenotypic expression across ethnicities in the United States. Design/Setting: Cases of narcolepsy from 1992 to 2013 were identified from searches of the Stanford Center for Narcolepsy Research database. International Classification of Sleep Disorders, Third Edition diagnosis criteria for type 1 and type 2 narcolepsy were used for inclusion, but subjects were separated as with and without cataplexy for the purpose of data presentation. Information extracted included demographics, ethnicity and clinical data, HLA-DQB1*06:02, polysomnography (PSG), multiple sleep latency test (MSLT) data, and cerebrospinal fluid (CSF) hypocretin-1 level. Patients: 182 African-Americans, 839 Caucasians, 35 Asians, and 41 Latinos with narcolepsy. Results: Sex ratio, PSG, and MSLT findings did not differ across ethnicities. Epworth Sleepiness Scale (ESS) score was higher and age of onset of sleepiness earlier in African Americans compared with other ethnicities. HLA-DQB1*06:02 positivity was higher in African Americans (91.0%) versus others (76.6% in Caucasians, 80.0% in Asians, and 65.0% in Latinos). CSF hypocretin-1 level, obtained in 222 patients, was more frequently low (≤ 110 pg/ml) in African Americans (93.9%) versus Caucasians (61.5%), Asians (85.7%) and Latinos (75.0%). In subjects with low CSF hypocretin-1, African Americans (28.3%) were 4.5 fold more likely to be without cataplexy when compared with Caucasians (8.1%). Conclusions: Narcolepsy in African Americans is characterized by earlier symptom onset, higher Epworth Sleepiness Scale score, higher HLA-DQB1*06:02 positivity, and low cerebrospinal fluid hypocretin-1 level in the absence of cataplexy. In African Americans, more subjects without cataplexy have type 1 narcolepsy. Citation: Kawai M, O'Hara R, Einen M, Lin L

  13. Greenhouse gas trading starts up

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    While nations decide on whether to sign on to the Kyoto Protocol on climate change, some countries and private companies are moving forward with greenhouse gas emissions trading.A 19 March report, "The Emerging International Greenhouse Gas Market," by the Pew Center on Global Climate Change, reports that about 65 greenhouse gas emissions trades for quantities above 1,000 metric tons of carbon dioxideequivalent already have occurred worldwide since 1996. Many of these trades have taken place under a voluntary, ad hoc framework, though the United Kingdom and Denmark have established their own domestic emissions trading programs.

  14. Remote heterodyne millimeter-wave over fiber based OFDM-PON with master-to-slave injected dual-mode colorless FPLD pair.

    PubMed

    Chen, Hsiang-Yu; Chi, Yu-Chieh; Lin, Gong-Ru

    2015-08-24

    A remote heterodyne millimeter-wave (MMW) carrier at 47.7 GHz over fiber synthesized with the master-to-slave injected dual-mode colorless FPLD pair is proposed, which enables the future connection between the wired fiber-optic 64-QAM OFDM-PON at 24 Gb/s with the MMW 4-QAM OFDM wireless network at 2 Gb/s. Both the single- and dual-mode master-to-slave injection-locked colorless FPLD pairs are compared to optimize the proposed 64-QAM OFDM-PON. For the unamplified single-mode master, the slave colorless FPLD successfully performs the 64-QAM OFDM data at 24 Gb/s with EVM, SNR and BER of 8.5%, 21.5 dB and 2.9 × 10(-3), respectively. In contrast, the dual-mode master-to-slave injection-locked colorless FPLD pair with amplified and unfiltered master can transmit 64-QAM OFDM data at 18 Gb/s over 25-km SMF to provide EVM, SNR and BER of 8.2%, 21.8 dB and 2.2 × 10(-3), respectively. For the dual-mode master-to-slave injection-locked colorless FPLD pair, even though the modal dispersion occurred during 25-km SMF transmission makes it sacrifice the usable OFDM bandwidth by only 1 GHz, which guarantees the sufficient encoding bitrate for the optically generated MMW carrier to implement the fusion of MMW wireless LAN and DWDM-PON with cost-effective and compact architecture. As a result, the 47.7-GHz MMW carrier remotely beat from the dual-mode master-to-slave injection-locked colorless FPLD pair exhibits an extremely narrow bandwidth of only 0.48 MHz. After frequency down-conversion operation, the 47.7-GHz MMW carrier successfully delivers 4-QAM OFDM data up to 2 Gb/s with EVM, SNR and BER of 33.5%, 9.51 dB and 1.4 × 10(-3), respectively.

  15. The genetic structure and history of Africans and African Americans.

    PubMed

    Tishkoff, Sarah A; Reed, Floyd A; Friedlaender, Françoise R; Ehret, Christopher; Ranciaro, Alessia; Froment, Alain; Hirbo, Jibril B; Awomoyi, Agnes A; Bodo, Jean-Marie; Doumbo, Ogobara; Ibrahim, Muntaser; Juma, Abdalla T; Kotze, Maritha J; Lema, Godfrey; Moore, Jason H; Mortensen, Holly; Nyambo, Thomas B; Omar, Sabah A; Powell, Kweli; Pretorius, Gideon S; Smith, Michael W; Thera, Mahamadou A; Wambebe, Charles; Weber, James L; Williams, Scott M

    2009-05-22

    Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, four African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic properties. We observed high levels of mixed ancestry in most populations, reflecting historical migration events across the continent. Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers and Pygmies). The ancestry of African Americans is predominantly from Niger-Kordofanian (approximately 71%), European (approximately 13%), and other African (approximately 8%) populations, although admixture levels varied considerably among individuals. This study helps tease apart the complex evolutionary history of Africans and African Americans, aiding both anthropological and genetic epidemiologic studies.

  16. Plumbing Curriculum Guide. Construction Trades. Michigan Trade and Industrial Education.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide is intended to help secondary teachers provide relevant training for an entry-level job in plumbing. Introductory materials include background information on trade and industrial education and program goals and safety information. Descriptions follow of the construction trades program, vocational cooperative…

  17. Elective: African Literature.

    ERIC Educational Resources Information Center

    Jenkins, Kenneth V.

    The make-up of a course in African literature for high school students is discussed. It is pointed out that the course can be constructed on already familiar lines. High school students will be able to describe clearly, for example, the relationship between environment and character or the dilemma of characters caught between traditional values…

  18. African Americans and Agriculture.

    ERIC Educational Resources Information Center

    Morgan, Joan

    2000-01-01

    Reviews the opportunities available in the field of agriculture for African American students and notes efforts of the 136 colleges of agriculture to publicize their offerings and recruit students. Profiles six black leaders in agriculture, highlighting their achievements in research and aid to developing countries. A table provides data on annual…

  19. African Literature: Selected Resources.

    ERIC Educational Resources Information Center

    Deschenes, Martin O.; Waters, Harold A.

    This bibliography of resources for the teaching of African literature includes over 100 citations of books, textbooks, anthologies, plays, novels, short stories, and periodicals in French and English. Publishing house addresses, audiovisual aids, professional organizations, and a course list are also cited. The books are listed under the following…

  20. Water in the Cratonic Mantle: Insights from FTIR Data on Lac de Gras Xenoliths (Slave Craton, Canada)

    NASA Astrophysics Data System (ADS)

    Peslier, A. H.; Brandon, A. D.; Schaffer, L. A.; O'Reilly, S. Y.; Griffin, W. L.; Morris, R. V.; Graff, T. G.; Agresti, D. G.

    2014-12-01

    The mantle lithosphere beneath the cratonic part of continents is the deepest (> 200 km) and oldest (>2-3 Ga) on Earth, remaining a conundrum as to how these cratonic roots could have resisted delamination by asthenospheric convection over time. Water, or trace H incorporated in mineral defects, could be a key player in the evolution of continental lithosphere because it influences melting and rheology of the mantle [e.g., 1]. Mantle xenoliths from the Lac de Gras kimberlite in the Slave craton [2] were analyzed by FTIR. The cratonic mantle beneath Lac de Gras is stratified with shallow (<145 km) oxidized ultradepleted peridotites and pyroxenites with evidence for carbonatitic metasomatism, underlain by reduced and less depleted peridotites metasomatized by kimberlite melts [3,4]. Peridotites analyzed so far have H2O contents in ppm weight of 7-100 in their olivines, 58 to 255 in their orthopyroxenes (opx), 11 to 84 in their garnet, and 139 in one clinopyroxene. A pyroxenite contains 58 ppm H2O in opx and 5 ppm H2O in its olivine and garnet. Olivine and garnet from the deep peridotites have a range of water contents extending to higher values than those from the shallow ones. The FTIR spectra of olivines from the shallow samples have more prominent Group II OH bands compared to the olivines from the deep samples, consistent with a more oxidized mantle environment [5]. The range of olivine water content is similar to that observed in Kaapvaal craton peridotites at the same depths (129-184 km [1]) but does not extend to as high values as those from Udachnaya (Siberian craton [6]). The Slave, Kaapvaal and Siberian cratons will be compared in terms of water content distribution, controls and role in cratonic root longevity. [1] Peslier et al. 2010 Nature 467, 78-81. [2] Aulbach et al. 2007 CMP 154, 409-427. [3] Creighton et al. 2009 CMP 157, 491-504. [4] Aulbach et al. 2013 CG 352, 153-169. [5] Bai & Kohlstedt 1993 PCM 19, 460-471. [6] Doucet et al. 2014 GCA 137, 159-187.

  1. Infrared spectral and carbon isotopic characteristics of micro- and macro-diamonds from the Panda kimberlite (Central Slave Craton, Canada)

    NASA Astrophysics Data System (ADS)

    Melton, G. L.; Stachel, T.; Stern, R. A.; Carlson, J.; Harris, J. W.

    2013-09-01

    One hundred and twenty-one micro-diamonds (< 1 mm) and 90 macro-diamonds (2.5 mm to 3.4 mm) from the Panda kimberlite (Ekati mine, Central Slave Craton, Canada) were analyzed for nitrogen content, nitrogen aggregation state (%B) and platelet and hydrogen peak areas (cm- 2). Micro-diamond nitrogen concentrations range from < 10 at. ppm to 1696 at. ppm (median = 805 at. ppm) and the median aggregation state is 23%B. Macro-diamonds range from < 10 at. ppm to 1260 at. ppm (median = 187 at. ppm) nitrogen and have a median nitrogen aggregation of 26%B. Platelet and hydrogen peaks were observed in 37% and 79% of the micro-diamonds and 79% and 56% of the macro-diamonds, respectively. Nitrogen based time averaged residence temperatures indicate that micro- and macro-diamonds experienced similar thermal mantle residence histories, both populations displaying bimodal residence temperature distributions with a gap between 1130 °C and 1160 °C (at 3.5 Ga residence). In addition, SIMS carbon isotopic analyses for the micro-diamonds were obtained: δ13C compositions range from - 6.9‰ to + 1.8‰ (median = - 4.3‰). CL imaging reveals distinct growth layers that in some samples differ by > 2‰, but mostly vary by < 0.5‰. Comparison of only the “gem-quality” samples (n = 49 micro- and 90 macro-diamonds) between the two diamond sets, indicates a statistically significant shift of + 1.3‰ in average δ13C from macro- to micro-diamonds and this shift documents distinct diamond forming fluids, fractionation process or growth histories. A broad transition to heavier isotopic values is also observed in connection to decreasing mantle residence temperatures. The bimodal mantle residence temperature distribution may coincide with the transition from highly depleted shallow to more fertile deep lithospheric mantle observed beneath the Central Slave Craton. The increase in δ13C with decreasing residence temperature (proxy for decreasing depth) is interpreted to reflect diamond

  2. Potential health risks posed by polycyclic aromatic hydrocarbons in muscle tissues of fishes from the Athabasca and Slave Rivers, Canada.

    PubMed

    Ohiozebau, Ehimai; Tendler, Brett; Codling, Garry; Kelly, Erin; Giesy, John P; Jones, Paul D

    2017-02-01

    Polycyclic aromatic hydrocarbons (PAHs) are released to the environment from oil sands operations and from natural sources in Alberta, Canada. Concentrations of 16 USEPA priority PAHs were measured in tissues of fishes collected from three locations on the Athabasca River in Alberta and two downstream locations on the Slave River in the Northwest Territories, Canada. A total of 425 individual fish were collected including 89 goldeye (Hiodon alosoides), 93 whitefish (Coregonus clupeaformis), 104 northern pike/jackfish (Esox lucius), 96 walleye (Sander vitreus) and 43 burbot/loche mariah/mariah (Lota lota). Fish were sampled during the summer and fall of 2011 and spring of 2012. Dorsal muscle of fishes from upstream reaches of the Athabasca River, close to oil sands extraction and upgrading activities, contained greater concentrations of individual PAHs than concentrations in muscle of fishes from further downstream in the Slave River. Concentrations of the sum of USEPA indicator PAHs (∑PAHs) in fishes collected in the vicinity of Fort McKay, closest to oil sands activities, varied among seasons with average concentrations ranging from 11 (burbot, summer) to 1.2 × 10(2) ng/g, wm (burbot, spring) with a mean of 48 ng/g, wm. Concentrations of ∑PAHs in fishes collected in the vicinity of Fort Resolution, the location most distant from oil sands activities, also varied among species and seasons, with average concentrations ranging from 4.3 (whitefish, summer) to 33 ng/g, wm (goldeye, summer) with a mean of 13 ng/g, wm. Significant differences in concentrations of ∑PAHs in muscle were observed within goldeye, jackfish, walleye and whitefish among sites. Health risks posed by PAHs to humans were assessed probabilistically using a B[a]P equivalents approach (B[a]Peq). The average lifetime risk of additional cancers for humans who consumed fish was deemed to be within an 'acceptable' range of risk (i.e., less than 10(-6)).

  3. 40 CFR 90.206 - Trading.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... engine manufacturers in trading, subject to the trading restriction specified in § 90.207(c)(2). (b) Credits for trading can be obtained from credits banked in previous model years or credits generated during the model year of the trading transaction. (c) Traded credits can be used for averaging,...

  4. 17 CFR 37.406 - Trade reconstruction.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Trade reconstruction. 37.406 Section 37.406 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SWAP EXECUTION FACILITIES Monitoring of Trading and Trade Processing § 37.406 Trade reconstruction. The swap...

  5. On financial markets trading

    NASA Astrophysics Data System (ADS)

    Matassini, Lorenzo; Franci, Fabio

    2001-01-01

    Starting from the observation of the real trading activity, we propose a model of a stockmarket simulating all the typical phases taking place in a stock exchange. We show that there is no need of several classes of agents once one has introduced realistic constraints in order to confine money, time, gain and loss within an appropriate range. The main ingredients are local and global coupling, randomness, Zipf distribution of resources and price formation when inserting an order. The simulation starts with the initial public offer and comprises the broadcasting of news/advertisements and the building of the book, where all the selling and buying orders are stored. The model is able to reproduce fat tails and clustered volatility, the two most significant characteristics of a real stockmarket, being driven by very intuitive parameters.

  6. 78 FR 69438 - AGOA: Trade and Investment Performance Overview; AGOA: Economic Effects of Providing Duty-Free...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    .... AGOA's effects on the business and investment climate in sub-Saharan Africa, including (1) the identification and description of changes, if any, in the business and investment climates in sub-Saharan African... preferences to reciprocal trade agreements, and any effects of the change for the developing country in...

  7. Extension Resources for International Trade

    ERIC Educational Resources Information Center

    Seal, Susan D.

    2016-01-01

    With the opening of additional trade partnerships, the reduction of global transportation and communication costs, and the increase in demand for U.S. agricultural products and services, international trade is an area of great importance to more and more Extension clients and stakeholders. This article provides information about the primary…

  8. Climate policy: Reforming emissions trading

    NASA Astrophysics Data System (ADS)

    Edenhofer, Ottmar

    2014-08-01

    Courageous steps are required to reform the European Union Emissions Trading Scheme. To this end, an independent carbon authority has been proposed -- this is a move in the right direction, but should be part of a much broader discussion about reforming emissions trading.

  9. Machine Trades Lab Management Guide.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Instructional Materials Lab.

    This manual was developed to guide machine trades instructors and vocational supervisors in sequencing laboratory instruction and controlling the flow of work for a 2-year machine trades training program. The first part of the guide provides information on program management (program description, safety concerns, academic issues, implementation…

  10. Human Factors in Financial Trading

    PubMed Central

    Leaver, Meghan; Reader, Tom W.

    2016-01-01

    Objective This study tests the reliability of a system (FINANS) to collect and analyze incident reports in the financial trading domain and is guided by a human factors taxonomy used to describe error in the trading domain. Background Research indicates the utility of applying human factors theory to understand error in finance, yet empirical research is lacking. We report on the development of the first system for capturing and analyzing human factors–related issues in operational trading incidents. Method In the first study, 20 incidents are analyzed by an expert user group against a referent standard to establish the reliability of FINANS. In the second study, 750 incidents are analyzed using distribution, mean, pathway, and associative analysis to describe the data. Results Kappa scores indicate that categories within FINANS can be reliably used to identify and extract data on human factors–related problems underlying trading incidents. Approximately 1% of trades (n = 750) lead to an incident. Slip/lapse (61%), situation awareness (51%), and teamwork (40%) were found to be the most common problems underlying incidents. For the most serious incidents, problems in situation awareness and teamwork were most common. Conclusion We show that (a) experts in the trading domain can reliably and accurately code human factors in incidents, (b) 1% of trades incur error, and (c) poor teamwork skills and situation awareness underpin the most critical incidents. Application This research provides data crucial for ameliorating risk within financial trading organizations, with implications for regulation and policy. PMID:27142394

  11. Readings in the Automotive Trade.

    ERIC Educational Resources Information Center

    DiGise, Joe

    Designed for reluctant readers in vocational high school, this selection of readings emphasizes general information about the automotive trade. Articles have been selected from a variety of auto magazines and trade journals. Each article is followed by an assortment of exercises designed to enable the student to further develop vocabulary and…

  12. The Readability of Trade Examinations.

    ERIC Educational Resources Information Center

    Gilmore, Alison; Wagner, Graham

    A 1982 study assessed the comparative reading comprehension levels and writing ability performance of Trades Certification Board (TCB) apprentices in five trades in New Zealand. Test data were collected for 1,389 apprentices and a comparison group of 361 secondary school students. The cloze procedure format was adopted for assessing apprentices'…

  13. Improving U.S. Trade.

    ERIC Educational Resources Information Center

    Bentsen, Lloyd

    1982-01-01

    Discusses the need to formulate a coherent trade policy in response to international economic realities. The author argues against a return to trade protectionism and supports efforts to establish workable reciprocity agreements. Increasing import tariffs on high technology products would control access to American markets. (AM)

  14. A simple tectonic model for crustal accretion in the Slave Province: A 2.7-2.5 Ga granite greenstone terrane

    NASA Technical Reports Server (NTRS)

    Hoffman, P. F.

    1986-01-01

    A prograding (direction unspecified) trench-arc system is favored as a simple yet comprehensive model for crustal generation in a 250,000 sq km granite-greenstone terrain. The model accounts for the evolutionary sequence of volcanism, sedimentation, deformation, metamorphism and plutonism, observed througout the Slave province. Both unconformable (trench inner slope) and subconformable (trench outer slope) relations between the volcanics and overlying turbidities; and the existence of relatively minor amounts of pre-greenstone basement (microcontinents) and syn-greenstone plutons (accreted arc roots) are explained. Predictions include: a varaiable gap between greenstone volcanism and trench turbidite sedimentation (accompanied by minor volcanism) and systematic regional variations in age span of volcanism and plutonism. Implications of the model will be illustrated with reference to a 1:1 million scale geological map of the Slave Province (and its bounding 1.0 Ga orogens).

  15. Force Display and Bi-Lateral Master-Slave Control with an Internal Model under the Consideration of Human Cross-Over Model

    NASA Astrophysics Data System (ADS)

    Kawahata, Nagakatsu; Nishizawa, Masanori; Itoh, Youichirou; Yoshida, Hiroaki

    Human behavior for controlling machines is quite adaptive but restrictive in gain, phase, frequency bandwidth and so on. It is often assumed by a cross-over model especially for compensatory tracking task. Force display system is increasingly important in robotics, remote manipulations, machine handling and etc. The control system design for force display and/or bi-lateral master-slave manipulator is not so easy because of gain limits, mechanical vibration, human-induced oscillation and others. Proposed is a control system design for force display and/or bi-lateral master-slave manipulator based on model-following control under the concept of human crossover model in compensatory tracking. Experimental results are also shown for an actual force display device designed by the proposed method.

  16. Coal trade means shipbuilders' goldmine

    SciTech Connect

    Ridgeway, J.

    1980-03-01

    Nowhere is the advent of a new international trade in coal more important than in the shipping industry. Since the middle of the last decade the world shipping industry has been in the doldrums. As the world switches slowly away from oil, the trade in coal probably will increase dramatically. As it does, the structure of the trade will change. Much of the coal will be shipped by water. During the past decade, US influence declined as the energy crisis changed the nature of the trade away from metallurgical coals to thermal coals. Shipping experts predict the dry bulk carriers that are used for coal, grain, and iron ore (a commodity whose trade is expected to increase) will replace the oil tankers as the most-important class of ships on the high seas by the year 2000.

  17. Protecting Trade Secrets in Canada.

    PubMed

    Courage, Noel; Calzavara, Janice

    2015-05-18

    Patents in the life sciences industries are a key form of intellectual property (IP), particularly for products such as brand-name drugs and medical devices. However, trade secrets can also be a useful tool for many types of innovations. In appropriate cases, trade secrets can offer long-term protection of IP for a lower financial cost than patenting. This type of protection must be approached with caution as there is little room for error when protecting a trade secret. Strong agreements and scrupulous security can help to protect the secret. Once a trade secret is disclosed to the public, it cannot be restored as the owner's property; however, if the information is kept from the public domain, the owner can have a property right of unlimited duration in the information. In some situations patents and trade secrets may be used cooperatively to protect innovation, particularly for manufacturing processes.

  18. Energy cost and return for hunting in African wild dogs and cheetahs

    PubMed Central

    Hubel, Tatjana Y.; Myatt, Julia P.; Jordan, Neil R.; Dewhirst, Oliver P.; McNutt, J. Weldon; Wilson, Alan M.

    2016-01-01

    African wild dogs (Lycaon pictus) are reported to hunt with energetically costly long chase distances. We used high-resolution GPS and inertial technology to record 1,119 high-speed chases of all members of a pack of six adult African wild dogs in northern Botswana. Dogs performed multiple short, high-speed, mostly unsuccessful chases to capture prey, while cheetahs (Acinonyx jubatus) undertook even shorter, higher-speed hunts. We used an energy balance model to show that the energy return from group hunting and feeding substantially outweighs the cost of multiple short chases, which indicates that African wild dogs are more energetically robust than previously believed. Comparison with cheetah illustrates the trade-off between sheer athleticism and high individual kill rate characteristic of cheetahs, and the energetic robustness of frequent opportunistic group hunting and feeding by African wild dogs. PMID:27023457

  19. Energy cost and return for hunting in African wild dogs and cheetahs.

    PubMed

    Hubel, Tatjana Y; Myatt, Julia P; Jordan, Neil R; Dewhirst, Oliver P; McNutt, J Weldon; Wilson, Alan M

    2016-03-29

    African wild dogs (Lycaon pictus) are reported to hunt with energetically costly long chase distances. We used high-resolution GPS and inertial technology to record 1,119 high-speed chases of all members of a pack of six adult African wild dogs in northern Botswana. Dogs performed multiple short, high-speed, mostly unsuccessful chases to capture prey, while cheetahs (Acinonyx jubatus) undertook even shorter, higher-speed hunts. We used an energy balance model to show that the energy return from group hunting and feeding substantially outweighs the cost of multiple short chases, which indicates that African wild dogs are more energetically robust than previously believed. Comparison with cheetah illustrates the trade-off between sheer athleticism and high individual kill rate characteristic of cheetahs, and the energetic robustness of frequent opportunistic group hunting and feeding by African wild dogs.

  20. Master-Leader-Slave Cuckoo Search with Parameter Control for ANN Optimization and Its Real-World Application to Water Quality Prediction.

    PubMed

    Jaddi, Najmeh Sadat; Abdullah, Salwani; Abdul Malek, Marlinda

    2017-01-01

    Artificial neural networks (ANNs) have been employed to solve a broad variety of tasks. The selection of an ANN model with appropriate weights is important in achieving accurate results. This paper presents an optimization strategy for ANN model selection based on the cuckoo search (CS) algorithm, which is rooted in the obligate brood parasitic actions of some cuckoo species. In order to enhance the convergence ability of basic CS, some modifications are proposed. The fraction Pa of the n nests replaced by new nests is a fixed parameter in basic CS. As the selection of Pa is a challenging issue and has a direct effect on exploration and therefore on convergence ability, in this work the Pa is set to a maximum value at initialization to achieve more exploration in early iterations and it is decreased during the search to achieve more exploitation in later iterations until it reaches the minimum value in the final iteration. In addition, a novel master-leader-slave multi-population strategy is used where the slaves employ the best fitness function among all slaves, which is selected by the leader under a certain condition. This fitness function is used for subsequent Lévy flights. In each iteration a copy of the best solution of each slave is migrated to the master and then the best solution is found by the master. The method is tested on benchmark classification and time series prediction problems and the statistical analysis proves the ability of the method. This method is also applied to a real-world water quality prediction problem with promising results.

  1. Master-Leader-Slave Cuckoo Search with Parameter Control for ANN Optimization and Its Real-World Application to Water Quality Prediction

    PubMed Central

    Jaddi, Najmeh Sadat; Abdullah, Salwani; Abdul Malek, Marlinda

    2017-01-01

    Artificial neural networks (ANNs) have been employed to solve a broad variety of tasks. The selection of an ANN model with appropriate weights is important in achieving accurate results. This paper presents an optimization strategy for ANN model selection based on the cuckoo search (CS) algorithm, which is rooted in the obligate brood parasitic actions of some cuckoo species. In order to enhance the convergence ability of basic CS, some modifications are proposed. The fraction Pa of the n nests replaced by new nests is a fixed parameter in basic CS. As the selection of Pa is a challenging issue and has a direct effect on exploration and therefore on convergence ability, in this work the Pa is set to a maximum value at initialization to achieve more exploration in early iterations and it is decreased during the search to achieve more exploitation in later iterations until it reaches the minimum value in the final iteration. In addition, a novel master-leader-slave multi-population strategy is used where the slaves employ the best fitness function among all slaves, which is selected by the leader under a certain condition. This fitness function is used for subsequent Lévy flights. In each iteration a copy of the best solution of each slave is migrated to the master and then the best solution is found by the master. The method is tested on benchmark classification and time series prediction problems and the statistical analysis proves the ability of the method. This method is also applied to a real-world water quality prediction problem with promising results. PMID:28125609

  2. Neural-adaptive control of single-master-multiple-slaves teleoperation for coordinated multiple mobile manipulators with time-varying communication delays and input uncertainties.

    PubMed

    Li, Zhijun; Su, Chun-Yi

    2013-09-01

    In this paper, adaptive neural network control is investigated for single-master-multiple-slaves teleoperation in consideration of time delays and input dead-zone uncertainties for multiple mobile manipulators carrying a common object in a cooperative manner. Firstly, concise dynamics of teleoperation systems consisting of a single master robot, multiple coordinated slave robots, and the object are developed in the task space. To handle asymmetric time-varying delays in communication channels and unknown asymmetric input dead zones, the nonlinear dynamics of the teleoperation system are transformed into two subsystems through feedback linearization: local master or slave dynamics including the unknown input dead zones and delayed dynamics for the purpose of synchronization. Then, a model reference neural network control strategy based on linear matrix inequalities (LMI) and adaptive techniques is proposed. The developed control approach ensures that the defined tracking errors converge to zero whereas the coordination internal force errors remain bounded and can be made arbitrarily small. Throughout this paper, stability analysis is performed via explicit Lyapunov techniques under specific LMI conditions. The proposed adaptive neural network control scheme is robust against motion disturbances, parametric uncertainties, time-varying delays, and input dead zones, which is validated by simulation studies.

  3. Nietzsche's Genealogy of Morality and the changing boundaries of medicine, psychiatry and psychiatric and mental health nursing practice: a slave revolt?

    PubMed

    Biley, F C

    2010-10-01

    The main constructions in Nietzsche's On the Genealogy of Morality (1994) are employed in order to explore the changes in mental health care that have been recently taking place. Characterized by boundaries that define the objectivity of scientific method, the biological stratum or the area of concern (disease and the disembodied being) and the professional distance that is maintained in the healthcare encounter, the noble morality of contemporary allopathic (Western) mental health care practice appears to be being challenged, in an act of ressentiment, by the slave morality of society, inverting values and beliefs that have previously been held. Mental health care paternalism may be in the process of giving way to consumer sovereignty, patient participation in decision making and the re-discovery of the embodied being at the centre of the healthcare encounter. Nietzsche warns that the dominance of slave morality and the inversion of moral values (what was a quality that was held by the nobles and regarded as good) - that is, objectivity and mental health care paternalism - becomes bad; and what was a quality held by the slaves and regarded as bad - subjectivity - becomes good, may ultimately be detrimental to the advancement of society.

  4. 77 FR 31393 - Labor Advisory Committee for Trade Negotiations and Trade Policy

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... of the Secretary Labor Advisory Committee for Trade Negotiations and Trade Policy ACTION: Notice of... Committee for Trade Negotiations and Trade Policy. The Committee will be chartered pursuant to section 135(c... Representative). Purpose: The Labor Advisory Committee for Trade Negotiations and Trade Policy consults with...

  5. 76 FR 58774 - Trade Mission to Southeast Asia in Conjunction With Trade Winds-Asia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-22

    ... International Trade Administration Trade Mission to Southeast Asia in Conjunction With Trade Winds-- Asia AGENCY... Winds--Asia business forum (which is also open to U.S. companies not participating in the trade mission) in Singapore next May. U.S. trade mission members will participate in the Trade Winds-- Asia...

  6. Force Control and Nonlinear Master-Slave Force Profile to Manage an Admittance Type Multi-Fingered Haptic User Interface

    SciTech Connect

    Anthony L. Crawford

    2012-08-01

    Natural movements and force feedback are important elements in using teleoperated equipment if complex and speedy manipulation tasks are to be accomplished in remote and/or hazardous environments, such as hot cells, glove boxes, decommissioning, explosives disarmament, and space to name a few. In order to achieve this end the research presented in this paper has developed an admittance type exoskeleton like multi-fingered haptic hand user interface that secures the user’s palm and provides 3-dimensional force feedback to the user’s fingertips. Atypical to conventional haptic hand user interfaces that limit themselves to integrating the human hand’s characteristics just into the system’s mechanical design this system also perpetuates that inspiration into the designed user interface’s controller. This is achieved by manifesting the property differences of manipulation and grasping activities as they pertain to the human hand into a nonlinear master-slave force relationship. The results presented in this paper show that the admittance-type system has sufficient bandwidth that it appears nearly transparent to the user when the user is in free motion and when the system is subjected to a manipulation task, increased performance is achieved using the nonlinear force relationship compared to the traditional linear scaling techniques implemented in the vast majority of systems.

  7. A master-slave parallel hybrid multi-objective evolutionary algorithm for groundwater remediation design under general hydrogeological conditions

    NASA Astrophysics Data System (ADS)

    Wu, J.; Yang, Y.; Luo, Q.; Wu, J.

    2012-12-01

    This study presents a new hybrid multi-objective evolutionary algorithm, the niched Pareto tabu search combined with a genetic algorithm (NPTSGA), whereby the global search ability of niched Pareto tabu search (NPTS) is improved by the diversification of candidate solutions arose from the evolving nondominated sorting genetic algorithm II (NSGA-II) population. Also, the NPTSGA coupled with the commonly used groundwater flow and transport codes, MODFLOW and MT3DMS, is developed for multi-objective optimal design of groundwater remediation systems. The proposed methodology is then applied to a large-scale field groundwater remediation system for cleanup of large trichloroethylene (TCE) plume at the Massachusetts Military Reservation (MMR) in Cape Cod, Massachusetts. Furthermore, a master-slave (MS) parallelization scheme based on the Message Passing Interface (MPI) is incorporated into the NPTSGA to implement objective function evaluations in distributed processor environment, which can greatly improve the efficiency of the NPTSGA in finding Pareto-optimal solutions to the real-world application. This study shows that the MS parallel NPTSGA in comparison with the original NPTS and NSGA-II can balance the tradeoff between diversity and optimality of solutions during the search process and is an efficient and effective tool for optimizing the multi-objective design of groundwater remediation systems under complicated hydrogeologic conditions.

  8. Mott transitions in a three-component Falicov-Kimball model: A slave boson mean-field study

    NASA Astrophysics Data System (ADS)

    Le, Duc-Anh; Tran, Minh-Tien

    2015-05-01

    Metal-insulator transitions in a three-component Falicov-Kimball model are investigated within the Kotliar-Ruckenstein slave boson mean-field approach. The model describes a mixture of two interacting fermion atom species loaded into an optical lattice at ultralow temperature. One species is two-component atoms, which can hop in the optical lattice, and the other is single-component atoms, which are localized. Different correlation-driven metal-insulator transitions are observed depending on the atom filling conditions and local interactions. These metal-insulator transitions are classified by the band renormalization factors and the double occupancies of the atom species. The filling conditions and the critical value of the local interactions for these metal-insulator transitions are also analytically established. The obtained results not only are in good agreement with the dynamical mean-field theory for the three-component Falicov-Kimball model but also clarify the nature and properties of the metal-insulator transitions in a simple physics picture.

  9. Spiral magnetism in the single-band Hubbard model: the Hartree-Fock and slave-boson approaches

    NASA Astrophysics Data System (ADS)

    Igoshev, P. A.; Timirgazin, M. A.; Gilmutdinov, V. F.; Arzhnikov, A. K.; Irkhin, V. Yu

    2015-11-01

    The ground-state magnetic phase diagram is investigated within the single-band Hubbard model for square and different cubic lattices. The results of employing the generalized non-correlated mean-field (Hartree-Fock) approximation and generalized slave-boson approach by Kotliar and Ruckenstein with correlation effects included are compared. We take into account commensurate ferromagnetic, antiferromagnetic, and incommensurate (spiral) magnetic phases, as well as phase separation into magnetic phases of different types, which was often lacking in previous investigations. It is found that the spiral states and especially ferromagnetism are generally strongly suppressed up to non-realistically large Hubbard U by the correlation effects if nesting is absent and van Hove singularities are well away from the paramagnetic phase Fermi level. The magnetic phase separation plays an important role in the formation of magnetic states, the corresponding phase regions being especially wide in the vicinity of half-filling. The details of non-collinear and collinear magnetic ordering for different cubic lattices are discussed.

  10. Mercury trends in predatory fish in Great Slave Lake: the influence of temperature and other climate drivers.

    PubMed

    Evans, Marlene; Muir, Derek; Brua, Robert B; Keating, Jonathan; Wang, Xiaowa

    2013-11-19

    Here we report on trends in mercury (Hg) concentrations in lake trout (Salvelinus namaycush), burbot (Lota lota), and northern pike (Esox lucius) from Great Slave Lake, located in the Mackenzie River Basin (MRB) and investigate how climate factors may be influencing these trends. Hg concentrations in lake trout and burbot increased significantly over the early 1990s to 2012 in the two major regions of the lake; no trend was evident for northern pike over 1999-2012. Temporal variations in Hg concentrations in lake trout and burbot were similar with respect to timing of peaks and troughs. Inclusion of climate variables based on annual means, particularly temperature, improved explanatory power for variations in Hg over analyses based only on year and fish length; unexpectedly, the temperature coefficient was negative. Climate analyses based on growing season means (defined as May-September) had less explanatory power suggesting that trends were more strongly associated with colder months within the year. Inclusion of the Pacific/North American index improved explanatory power for the lake trout model suggesting that trends may have been affected by air circulation patterns. Overall, while our study confirmed previously reported trends of Hg increase in burbot in the MRB, we found no evidence that these trends were directly driven by increasing temperatures and productivity.

  11. Life history differences between fat and lean morphs of lake charr (Salvelinus namaycush) in Great Slave Lake, Northwest Territories, Canada

    USGS Publications Warehouse

    Hansen, Michael J.; Nate, Nancy A.; Chavarie, Louise; Muir, Andrew M.; Zimmerman, Mara S.; Krueger, Charles C.

    2016-01-01

    Life history characteristics (size, age, plumpness, buoyancy, survival, growth, and maturity) were compared between fat and lean morphs of lake charr Salvelinus namaycush in Great Slave Lake, Canada, to determine if differences may reflect effects of resource polymorphism. Lake charr were sampled using graded-mesh gill nets set in three depth strata. Of 236 lake charr captured, 122 were a fat morph and 114 were a lean morph. Males and females did not differ from each other in any attributes for either fat or lean morphs. The fat morph averaged 15 mm longer, 481 g heavier, and 4.7 years older than the lean morph. The fat morph averaged 26% heavier and 48% more buoyant at length than the lean morph. Survival of the fat morph was 1.7% higher than that of the lean morph. The fat morph grew at a slower annual rate to a shorter asymptotic length than the lean morph. Fat and lean morphs matured at similar lengths and ages. We concluded that the connection between resource polymorphism and life histories in lean versus fat lake charr suggests that morph-specific restoration objectives may be needed in lakes where lake charr diversity is considered to be a restoration goal.

  12. Products of biotransformation of polycyclic aromatic hydrocarbons in fishes of the Athabasca/Slave river system, Canada.

    PubMed

    Ohiozebau, Ehimai; Tendler, Brett; Hill, Allison; Codling, Garry; Kelly, Erin; Giesy, John P; Jones, Paul D

    2016-04-01

    Concentrations of products of biotransformation of polycyclic aromatic hydrocarbons (PBPAH) were measured in bile of five fishes of nutritional, cultural and ecological relevance from the Athabasca/Slave river system. Samples were collected in Alberta and the Northwest Territories, Canada, during three seasons. As a measure of concentrations of PBPAHs to which fishes are exposed and to gain information on the nature and extent of potential exposures of people or piscivorous wildlife, concentrations of biotransformation products of two- and three-ringed, four-ringed and five-ringed PAHs were measured using synchronous fluorescence spectroscopy. Spatial and seasonal differences were observed with greater concentrations of PBPAHs in samples of bile of fish collected from Fort McKay as well as greater concentrations of PBPAHs in bile of fish collected during summer compared to those collected in other seasons. Overall, PBPAHs were greater in fishes of lower trophic levels and fishes more closely associated with sediments. In particular, goldeye (Hiodon alosoides), consistently contained greater concentrations of all the PBPAHs studied.

  13. Trade Unions and the Economics Curriculum.

    ERIC Educational Resources Information Center

    Veale, Sarah

    1987-01-01

    Contends that a realistic approach to teaching economics requires learning about trade unions. Presents a role play of a trade union meeting that helps students think about how trade unions tackle problems. (BSR)

  14. Water Quality Trading Toolkit for Permit Writers

    EPA Pesticide Factsheets

    The Water Quality Trading Toolkit for Permit Writers is EPA’s first “how-to” manual on designing and implementing water quality trading programs. It helps NPDES permitting authorities incorporate trading provisions into permits.

  15. Africa gaining importance in world LPG trade

    SciTech Connect

    Haun, R.R.; Otto, K.W.; Whitley, S.C.

    1997-05-12

    Major LPG projects planned or under way in Africa will increase the importance of that region`s presence in world LPG trade. Supplies will nearly double between 1995 and 2005, at which time they will remain steady for at least 10 years. At the same time that exports are leveling, however, increasing domestic demand for PG is likely to reduce export-market participation by Algeria, Nigeria, Egypt, and Libya. The growth of Africa`s participation in world LPG supply is reflected in comparisons for the next 15--20 years. Total world supply of LPG in 1995 was about 165 million metric tons (tonnes), of which Africans share was 7.8 million tonnes. By 2000, world supply will grow to slightly more than 200 million tonnes, with Africa`s share expected to increase to 13.2 million tonnes (6.6%). And by 2005, world LPG supply will reach nearly 230 million tonnes; Africa`s overall supply volumes by that year will be nearly 16.2 million tonnes (7%). World LPG supply for export in 1995 was on order of 44 million tonnes with Africa supply about 4 million tonnes (9%). By 2005, world export volumes of LPG will reach nearly 70 million tonnes; Africa`s share will have grown by nearly 10 million tonnes (14.3%).

  16. The economics of parallel trade.

    PubMed

    Danzon, P M

    1998-03-01

    The potential for parallel trade in the European Union (EU) has grown with the accession of low price countries and the harmonisation of registration requirements. Parallel trade implies a conflict between the principle of autonomy of member states to set their own pharmaceutical prices, the principle of free trade and the industrial policy goal of promoting innovative research and development (R&D). Parallel trade in pharmaceuticals does not yield the normal efficiency gains from trade because countries achieve low pharmaceutical prices by aggressive regulation, not through superior efficiency. In fact, parallel trade reduces economic welfare by undermining price differentials between markets. Pharmaceutical R&D is a global joint cost of serving all consumers worldwide; it accounts for roughly 30% of total costs. Optimal (welfare maximising) pricing to cover joint costs (Ramsey pricing) requires setting different prices in different markets, based on inverse demand elasticities. By contrast, parallel trade and regulation based on international price comparisons tend to force price convergence across markets. In response, manufacturers attempt to set a uniform 'euro' price. The primary losers from 'euro' pricing will be consumers in low income countries who will face higher prices or loss of access to new drugs. In the long run, even higher income countries are likely to be worse off with uniform prices, because fewer drugs will be developed. One policy option to preserve price differentials is to exempt on-patent products from parallel trade. An alternative is confidential contracting between individual manufacturers and governments to provide country-specific ex post discounts from the single 'euro' wholesale price, similar to rebates used by managed care in the US. This would preserve differentials in transactions prices even if parallel trade forces convergence of wholesale prices.

  17. Design Trades for WFIRST

    NASA Astrophysics Data System (ADS)

    Danner, Rolf; Casement, S. L.; Lillie, C.; Lo, A.; Oleas, G.; Shapiro, K.; Spittler, C.

    2011-01-01

    The Wide Field Infrared Space Telescope, WFIRST, was recommended as the highest priority mission for the next decade by the National Research Council in their 2010 report "New Worlds, New Horizons in Astronomy and Astrophysics.” The mission aims to measure the properties of dark energy via three different techniques: weak lensing, baryon acoustic oscillations and detecting distant supernova explosions. WFIRST will also search for micro-lensing events caused by extrasolar planets, and perform a near infrared sky survey. Here, we present a fresh look at WFIRST by tracing the science and mission requirements to the three mission concepts that formed the basis of WFIRST and incorporating them into a consistent set. We expect that these requirements will further evolve as NASA evolves the program and use this representative set as an interim solution. From there, we highlight the requirements that are expected to drive the design and evaluate current capabilities based on current and past missions such as the James Webb Space Telescope, the Space Interferometry Mission, and other mission concepts. We ask what makes the project hard to do. What have we learned from other missions that we can bring to WFIRST? Are there any options that would significantly reduce cost or risk while preserving the science return? Finally, we present a preliminary design concept and identify key trades that will lead to a robust, affordable design that meets all science and mission requirements. We conclude with a preview of future work we expect to perform over the next year.

  18. Understanding traditional African healing

    PubMed Central

    MOKGOBI, M.G.

    2015-01-01

    Traditional African healing has been in existence for many centuries yet many people still seem not to understand how it relates to God and religion/spirituality. Some people seem to believe that traditional healers worship the ancestors and not God. It is therefore the aim of this paper to clarify this relationship by discussing a chain of communication between the worshipers and the Almighty God. Other aspects of traditional healing namely types of traditional healers, training of traditional healers as well as the role of traditional healers in their communities are discussed. In conclusion, the services of traditional healers go far beyond the uses of herbs for physical illnesses. Traditional healers serve many roles which include but not limited to custodians of the traditional African religion and customs, educators about culture, counselors, social workers and psychologists. PMID:26594664

  19. Trade and the environment: Discussion

    SciTech Connect

    Lutz, E.

    1992-12-01

    The author presents a synopsis of several papers on the issue of international trade and the environment. The papers address the following topics: the complex interrelationships of international trade, environment, and poverty in developing countries; environmental aspects of economic relations between nations; and the debate between environmentalists and free trade advocates. The author also adds comments about the US embargo on Mexican yellow-fin tuna imports, concluding that this unilateral embargo action, while initially creating tentions, may have provided a useful impetus to working out a multinational environmental standard.

  20. Ectoparasites of African Mammals.

    DTIC Science & Technology

    1976-11-30

    This study consisted of ectoparasites from approximately 100,000 African small mammals, representing probably more than 500 species of which many are...study of ectoparasites may provide information concerning interactions among animal reservoirs of disease, and (3) an understanding of ecological...parameters for ectoparasites and their hosts may enhance understanding of epidemiological patterns. Of the four major groups dealt with, considerably more

  1. Diversity among African Pygmies

    PubMed Central

    Ramírez Rozzi, Fernando V.; Sardi, Marina L.

    2010-01-01

    Although dissimilarities in cranial and post-cranial morphology among African pygmies groups have been recognized, comparative studies on skull morphology usually pull all pygmies together assuming that morphological characters are similar among them and different with respect to other populations. The main aim of this study is to compare cranial morphology between African pygmies and non-pygmies populations from Equatorial Africa derived from both the Eastern and the Western regions in order to test if the greatest morphological difference is obtained in the comparison between pygmies and non-pygmies. Thirty three-dimensional (3D) landmarks registered with Microscribe in four cranial samples (Western and Eastern pygmies and non-pygmies) were obtained. Multivariate analysis (generalized Procrustes analysis, Mahalanobis distances, multivariate regression) and complementary dimensions of size were evaluated with ANOVA and post hoc LSD. Results suggest that important cranial shape differentiation does occur between pygmies and non-pygmies but also between Eastern and Western populations and that size changes and allometries do not affect similarly Eastern and Western pygmies. Therefore, our findings raise serious doubt about the fact to consider African pygmies as a homogenous group in studies on skull morphology. Differences in cranial morphology among pygmies would suggest differentiation after divergence. Although not directly related to skull differentiation, the diversity among pygmies would probably suggest that the process responsible for reduced stature occurred after the split of the ancestors of modern Eastern and Western pygmies. PMID:21049030

  2. Human African trypanosomiasis.

    PubMed

    Lejon, Veerle; Bentivoglio, Marina; Franco, José Ramon

    2013-01-01

    Human African trypanosomiasis or sleeping sickness is a neglected tropical disease that affects populations in sub-Saharan Africa. The disease is caused by infection with the gambiense and rhodesiense subspecies of the extracellular parasite Trypanosoma brucei, and is transmitted to humans by bites of infected tsetse flies. The disease evolves in two stages, the hemolymphatic and meningoencephalitic stages, the latter being defined by central nervous system infection after trypanosomal traversal of the blood-brain barrier. African trypanosomiasis, which leads to severe neuroinflammation, is fatal without treatment, but the available drugs are toxic and complicated to administer. The choice of medication is determined by the infecting parasite subspecies and disease stage. Clinical features include a constellation of nonspecific symptoms and signs with evolving neurological and psychiatric alterations and characteristic sleep-wake disturbances. Because of the clinical profile variability and insidiously progressive central nervous system involvement, disease staging is currently based on cerebrospinal fluid examination, which is usually performed after the finding of trypanosomes in blood or other body fluids. No vaccine being available, control of human African trypanosomiasis relies on diagnosis and treatment of infected patients, assisted by vector control. Better diagnostic tools and safer, easy to use drugs are needed to facilitate elimination of the disease.

  3. East African Rift Valley, Kenya

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This rare, cloud free view of the East African Rift Valley, Kenya (1.5N, 35.5E) shows a clear view of the Turkwell River Valley, an offshoot of the African REift System. The East African Rift is part of a vast plate fracture which extends from southern Turkey, through the Red Sea, East Africa and into Mozambique. Dark green patches of forests are seen along the rift margin and tea plantations occupy the cooler higher ground.

  4. To Live Like a Pig and Die Like a Dog: Environmental Implications for World War I in East Africa

    DTIC Science & Technology

    2009-12-03

    resulted from World War I was enormous; arguably only the legacy of the slave trade produced more adverse consequences for the African population.”3...Having reviewed the academic literature regarding the subject, an overview of the African terrain and history 6 constitutes the next logical step...coasts. By the end of the first decade of the twentieth century only Liberia and Ethiopia, comprising less than four percent of the African continent

  5. Is the United States Africa Command on Track

    DTIC Science & Technology

    2010-03-01

    Given Africa’s experience in the hands of Western governments, from slave trade to colonialism, to the hemispheric Cold War hegemonic struggles...and Partnership, Global Peace Operations Initiative, China and African Countries CLASSIFICATION: Unclassified The February 2007 decision to...focused on supporting “ African solutions to African problems.” Its critics allege that the command demonstrates a self-serving American policy focused

  6. Private Trade and Technical Schools.

    ERIC Educational Resources Information Center

    David, Christopher

    1983-01-01

    Among the advantages of private trade and technical schools is their market orientation, a sensitivity to employers' current needs. Teachers recruited from industry, accelerated pace, flexible scheduling, and emphasis on job placement are other benefits found in proprietary schools. (SK)

  7. To trade or not to trade: firm-level analysis of emissions trading in Santiago, Chile.

    PubMed

    Coria, Jessica; Löfgren, Asa; Sterner, Thomas

    2010-11-01

    Whether tradable permits are appropriate for use in transition and developing economies--given special social and cultural circumstances, such as the lack of institutions and lack of expertise with market-based policies--is much debated. We conducted interviews and surveyed a sample of firms subject to emissions trading programs in Santiago, Chile, one of the first cities outside the OECD that has implemented such trading. The information gathered allows us to study what factors affect the performance of the trading programs in practice and the challenges and advantages of applying tradable permits in less developed countries.

  8. Ivory Harvesting Pressure on the Genome of the African Elephant: A Phenotypic Shift to Tusklessness.

    PubMed

    Raubenheimer, Erich J; Miniggio, Hilde D

    2016-09-01

    The unique chequered pattern of elephant ivory has made it a desired commodity for the production of various works of art. The demand however outstrips the supply and with soaring prices, illegal tusk harvesting is thriving on the African continent. Formal restrictions placed on trade in elephant products have been ineffective in reversing the rapid decline in elephant numbers. We are presently facing the reality of extinction of free roaming elephant on the African continent. This paper describes the histogenesis of the chequered pattern, the genomic impact of ivory harvesting on the phenotype of breeding herds, and the contribution of science to tracing the origin of illegal ivory.

  9. 27 CFR 19.165 - Trade names.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Trade names. 19.165 Section 19.165 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Trade names. (a) Operating permits. Where a trade name is to be used in connection with the...

  10. 40 CFR 89.206 - Trading.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... averaging set in trading. (2) Credits for trading can be obtained from credits banked in a previous model year or credits generated during the model year of the trading transaction. (3) Traded credits can be....204(c). (b) Requirements for Tier 2 and later engines rated at or above 37 kW and Tier 1 and...

  11. Trade Is Everybody's Business [and] Teacher's Guide.

    ERIC Educational Resources Information Center

    Aaronson, Susan A.

    Trade has been an important factor in United States from the 17th century to the present day. The United States was born out of a trade dispute with Great Britain. From the moment the founders first set pen to paper, trade has helped spur U.S. economic growth. This booklet covers trade topics such as policy, perspectives, difference in nations…

  12. [The African Charter on the Rights of the Child. The member states of the Organization of African Unity must ratify without further delay].

    PubMed

    Diongue, A

    1994-12-01

    In July 1990, the Organization of African Unity (OUA) adopted the African Charter of the Rights and Welfare of the Child. It includes a Preamble, two relative parts on the Rights and Respects of the Child, and 47 articles. It defines "child" as a complete human being less than 18 years old. It recognizes the child's unique and privileged place in African society and that African children need protection and special care. It also recognizes that the child has freedom of expression, association, peaceful assembly, thought, religion, and conscience. It aims to protect the private life of the child and safeguard the child against all forms of economic exploitation and against work that is hazardous, interferes with the child's education, or compromises his/her health or physical, social, mental, spiritual, and moral development. It also calls for protection against abuse and bad treatment, negative social and cultural practices, all forms of exploitation or sexual abuse, and illegal drug use. It also aims to prevent the sale, trading, kidnapping, and begging of children. It calls for the creation of an African expert committee on the rights and well-being of the child. Its mission is to promote and protect the rights consecrated by the Charter, to practice applying these rights, and to interpret the disposition of the Charter as required of party states, OUA institutions, or all other institutions recognized by OUA or by a member state. The Charter goes into effect 30 days after OUA or 15 member states ratify it. As of August 24, 1994, only four states had ratified it. Member states have taken it upon themselves to take all necessary measures to adopt the Charter. The delay of African states in this affair is incomprehensible. Eleven years separate the adoption of the Declaration on the Rights and Welfare of the African Child and this Charter. Must the African child wait as long to see the Charter become law?

  13. Elder Abuse among African Americans

    ERIC Educational Resources Information Center

    Tauriac, Jesse J.; Scruggs, Natoschia

    2006-01-01

    Perceptions of extreme, moderate, and mild forms of elder abuse among African-American women (n=25) and men (n=10) were examined. African-American respondents emphasized physical abuse when giving examples of extremely abusive behavior. Along with physical abuse, verbal abuse was the most frequently identified form of abuse, and was significantly…

  14. African ethics and voluntary euthanasia.

    PubMed

    Omonzejele, P F

    2004-01-01

    This paper outlines the relationship between euthanasia and its ethical norms and practices in a part of West Africa. The various sub-types of euthanasia are described in detail, parallel with the role of African ethical theories in determining their relevance. The author discusses the implications of this approach relative to the social and economic state of African communities.

  15. African American Administrators and Staff

    ERIC Educational Resources Information Center

    Wright, Dianne; Taylor, Janice D.; Burrell, Charlotte; Stewart, Gregory

    2006-01-01

    This article explores the issues of African American participation in the administrative ranks of the academy. The authors find that African Americans tend to hold positions that are marginal in academic organizations, lacking power and influence, and that not much has changed over recent decades. Forces influencing this condition are explored,…

  16. African-Americans and Alcoholism.

    ERIC Educational Resources Information Center

    Sigmon, Scott B.

    To better serve people in a counseling relationship, it is useful to understand them not only culturally, but demographically as well. This paper traces historical, religious, demographic aspects and treatment of alcohol abuse in African Americans. Historically, alcohol abuse and alcohol dependence have varied for African Americans. During the…

  17. Africanization in the United States

    PubMed Central

    Pinto, M. Alice; Rubink, William L.; Patton, John C.; Coulson, Robert N.; Johnston, J. Spencer

    2005-01-01

    The expansion of Africanized honeybees from South America to the southwestern United States in <50 years is considered one of the most spectacular biological invasions yet documented. In the American tropics, it has been shown that during their expansion Africanized honeybees have low levels of introgressed alleles from resident European populations. In the United States, it has been speculated, but not shown, that Africanized honeybees would hybridize extensively with European honeybees. Here we report a continuous 11-year study investigating temporal changes in the genetic structure of a feral population from the southern United States undergoing Africanization. Our microsatellite data showed that (1) the process of Africanization involved both maternal and paternal bidirectional gene flow between European and Africanized honeybees and (2) the panmitic European population was replaced by panmitic mixtures of A. m. scutellata and European genes within 5 years after Africanization. The post-Africanization gene pool (1998–2001) was composed of a diverse array of recombinant classes with a substantial European genetic contribution (mean 25–37%). Therefore, the resulting feral honeybee population of south Texas was best viewed as a hybrid swarm. PMID:15937139

  18. 78 FR 72929 - Labor Advisory Committee for Trade Negotiations and Trade Policy

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-04

    ... Advisory Committee for Trade Negotiations and Trade Policy AGENCY: Office of the Secretary, Bureau of... meeting of the Labor Advisory Committee for Trade Negotiation and Trade Policy. Date, Time, Place... in current and anticipated trade negotiations will be discussed. Pursuant to 19 U.S.C....

  19. 48 CFR 225.403 - World Trade Organization Government Procurement Agreement and Free Trade Agreements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false World Trade Organization... FOREIGN ACQUISITION Trade Agreements 225.403 World Trade Organization Government Procurement Agreement and Free Trade Agreements. (c) For acquisitions of supplies covered by the World Trade...

  20. 48 CFR 225.403 - World Trade Organization Government Procurement Agreement and Free Trade Agreements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false World Trade Organization... FOREIGN ACQUISITION Trade Agreements 225.403 World Trade Organization Government Procurement Agreement and Free Trade Agreements. (c) For acquisitions of supplies covered by the World Trade...

  1. 48 CFR 225.403 - World Trade Organization Government Procurement Agreement and Free Trade Agreements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false World Trade Organization... FOREIGN ACQUISITION Trade Agreements 225.403 World Trade Organization Government Procurement Agreement and Free Trade Agreements. (c) For acquisitions of supplies covered by the World Trade...

  2. The African contribution to the present-day population of the Azores Islands (Portugal): analysis of the Y chromosome haplogroup E.

    PubMed

    Neto, Domingos; Montiel, Rafael; Bettencourt, Conceição; Santos, Cristina; Prata, Maria J; Lima, Manuela

    2007-01-01

    Among the settlers that, from 1432 onwards, arrived to the Azores Islands were individuals of North and sub-Saharan African origin. A previous study of markers of the Y chromosome revealed that haplogroup E is the second more frequent in the Azores (13%). Since this haplogroup is heterogeneous and may contain subtypes of African or non-African origin, we analyzed an extended sample of 319 Azoreans, originating from the three groups of islands (Eastern, Central, and Western), to evaluate the African contribution to the present-day population of the Azores. Samples belonging to the E clade were distributed into six haplogroups, from which the most frequent was E3b1a, representing 47.2% of the E chromosomes (6.3% of the total sample). The sub-Saharan haplogroup E3a was found in 7.1% of E chromosomes (0.9% of the total), corresponding to the highest frequency reported so far in a Portuguese population. No significant differences were detected in the haplogroup distribution among groups of islands, as well as between Azores and most of other European populations compared. The present-day representation of sub-Saharan lineages in Azores, although reduced, is higher than in other Portuguese populations, where the demographic representation of sub-Saharan slaves is reported as similar.

  3. Cancer statistics for African Americans.

    PubMed

    Ghafoor, Asma; Jemal, Ahmedin; Cokkinides, Vilma; Cardinez, Cheryll; Murray, Taylor; Samuels, Alicia; Thun, Michael J

    2002-01-01

    The American Cancer Society provides estimates on the number of new cancer cases and deaths, and compiles health statistics on African Americans in a biennial publication, Cancer Facts and Figures for African Americans. The compiled statistics include cancer incidence, mortality, survival, and lifestyle behaviors using the most recent data on incidence and survival from the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) program, mortality data from the National Center for Health Statistics (NCHS), and behavioral information from the Behavior Risk Factor Surveillance System (BRFSS), Youth Risk Behavior Surveillance System (YRBSS), and National Health Interview Survey (NHIS). It is estimated that 132,700 new cases of cancer and 63,100 deaths will occur among African Americans in the year 2003. Although African Americans have experienced higher incidence and mortality rates of cancer than whites for many years, incidence rates have declined by 2.7 percent per year in African-American males since 1992, while stabilizing in African-American females. During the same period, death rates declined by 2.1 percent and 0.4 percent per year among African-American males and females, respectively. The decrease in both incidence and death rates from cancer among African-American males was the largest of any racial or ethnic group. Nonetheless, African Americans still carry the highest cancer burden among US racial and ethnic groups. Most cancers detectable by screening are diagnosed at a later stage and survival rates are lower within each stage of disease in African Americans than in whites. The extent to which these disparities reflect unequal access to health care versus other factors is an active area of research.

  4. Scaling Effect In Trade Network

    NASA Astrophysics Data System (ADS)

    Konar, M.; Lin, X.; Rushforth, R.; Ruddell, B. L.; Reimer, J.

    2015-12-01

    Scaling is an important issue in the physical sciences. Economic trade is increasingly of interest to the scientific community due to the natural resources (e.g. water, carbon, nutrients, etc.) embodied in traded commodities. Trade refers to the spatial and temporal redistribution of commodities, and is typically measured annually between countries. However, commodity exchange networks occur at many different scales, though data availability at finer temporal and spatial resolution is rare. Exchange networks may prove an important adaptation measure to cope with future climate and economic shocks. As such, it is essential to understand how commodity exchange networks scale, so that we can understand opportunities and roadblocks to the spatial and temporal redistribution of goods and services. To this end, we present an empirical analysis of trade systems across three spatial scales: global, sub-national in the United States, and county-scale in the United States. We compare and contrast the network properties, the self-sufficiency ratio, and performance of the gravity model of trade for these three exchange systems.

  5. East African ROAD

    NASA Astrophysics Data System (ADS)

    Tekle, Kelali

    2016-10-01

    In the developing world astronomy had been treated as the science of elites. As a result of this overwhelming perception, astronomy compared with other applied sciences has got less attention and its role in development has been insignificant. However, the IAU General Assembly decision in 2009 opened new opportunity for countries and professionals to deeply look into Astronomy and its role in development. Then, the subsequent establishment of regional offices in the developing world is helping countries to integrate astronomy with other earth and space based sciences so as to progressively promote its scientific and development importance. Gradually nations have come to know that space is the frontier of tomorrow and the urgency of preeminence on space frontier starts at primary school and ascends to tertiary education. For this to happen, member nations in east African region have placed STEM education at the center of their education system. For instance, Ethiopian has changed University enrollment strategy to be in favor of science and engineering subjects, i.e. every year seventy percent of new University entrants join science and engineering fields while thirty percent social science and humanities. Such bold actions truly promote astronomy to be conceived as gateway to science and technology. To promote the concept of astronomy for development the East African regional office has actually aligned it activities to be in line with the focus areas identified by the IAU strategy (2010 to 2020).

  6. African oil plays

    SciTech Connect

    Clifford, A.J. )

    1989-09-01

    The vast continent of Africa hosts over eight sedimentary basins, covering approximately half its total area. Of these basins, only 82% have entered a mature exploration phase, 9% have had little or no exploration at all. Since oil was first discovered in Africa during the mid-1950s, old play concepts continue to bear fruit, for example in Egypt and Nigeria, while new play concepts promise to become more important, such as in Algeria, Angola, Chad, Egypt, Gabon, and Sudan. The most exciting developments of recent years in African oil exploration are: (1) the Gamba/Dentale play, onshore Gabon; (2) the Pinda play, offshore Angola; (3) the Lucula/Toca play, offshore Cabinda; (4) the Metlaoui play, offshore Libya/Tunisia; (5) the mid-Cretaceous sand play, Chad/Sudan; and (6) the TAG-I/F6 play, onshore Algeria. Examples of these plays are illustrated along with some of the more traditional oil plays. Where are the future oil plays likely to develop No doubt, the Saharan basins of Algeria and Libya will feature strongly, also the presalt of Equatorial West Africa, the Central African Rift System and, more speculatively, offshore Ethiopia and Namibia, and onshore Madagascar, Mozambique, and Tanzania.

  7. Bioenergy and African transformation.

    PubMed

    Lynd, Lee R; Sow, Mariam; Chimphango, Annie Fa; Cortez, Luis Ab; Brito Cruz, Carlos H; Elmissiry, Mosad; Laser, Mark; Mayaki, Ibrahim A; Moraes, Marcia Afd; Nogueira, Luiz Ah; Wolfaardt, Gideon M; Woods, Jeremy; van Zyl, Willem H

    2015-01-01

    Among the world's continents, Africa has the highest incidence of food insecurity and poverty and the highest rates of population growth. Yet Africa also has the most arable land, the lowest crop yields, and by far the most plentiful land resources relative to energy demand. It is thus of interest to examine the potential of expanded modern bioenergy production in Africa. Here we consider bioenergy as an enabler for development, and provide an overview of modern bioenergy technologies with a comment on application in an Africa context. Experience with bioenergy in Africa offers evidence of social benefits and also some important lessons. In Brazil, social development, agricultural development and food security, and bioenergy development have been synergistic rather than antagonistic. Realizing similar success in African countries will require clear vision, good governance, and adaptation of technologies, knowledge, and business models to myriad local circumstances. Strategies for integrated production of food crops, livestock, and bioenergy are potentially attractive and offer an alternative to an agricultural model featuring specialized land use. If done thoughtfully, there is considerable evidence that food security and economic development in Africa can be addressed more effectively with modern bioenergy than without it. Modern bioenergy can be an agent of African transformation, with potential social benefits accruing to multiple sectors and extending well beyond energy supply per se. Potential negative impacts also cut across sectors. Thus, institutionally inclusive multi-sector legislative structures will be more effective at maximizing the social benefits of bioenergy compared to institutionally exclusive, single-sector structures.

  8. A Re Os isotope and PGE study of kimberlite-derived peridotite xenoliths from Somerset Island and a comparison to the Slave and Kaapvaal cratons

    NASA Astrophysics Data System (ADS)

    Irvine, Gordon J.; Pearson, D. Graham; Kjarsgaard, B. A.; Carlson, R. W.; Kopylova, M. G.; Dreibus, G.

    2003-12-01

    The concentrations of platinum-group elements (PGE; Os, Ir, Ru, Pd and Pt) and Re, and the Os isotopic compositions were determined for 33 lithospheric mantle peridotite xenoliths from the Somerset Island kimberlite field. The Os isotopic compositions are exclusively less radiogenic than estimates of bulk-earth ( 187Os/ 188Os as low as 0.1084) and require a long-term evolution in a low Re-Os environment. Re depletion model ages ( TRD) indicate that the cratonic lithosphere of Somerset Island stabilised by at least 2.8 Ga, i.e. in the Neoarchean and survived into the Mesozoic to be sampled by Cretaceous kimberlite magmatism. An Archean origin also is supported by thermobarometry (Archean lithospheric keels are characterised by >150 km thick lithosphere), modal mineralogy and mineral chemistry observations. The oldest ages recorded in the lithospheric mantle beneath Somerset Island are younger than the Mesoarchean (>3 Ga) ages recorded in the Slave craton lithospheric mantle to the southwest [Irvine, G.J., et al., 1999. Age of the lithospheric mantle beneath and around the Slave craton: a Rhenium-Osmium isotopic study of peridotite xenoliths from the Jericho and Somerset Island kimberlites. Ninth Annual V.M. Goldschmidt Conf., LPI Cont., 971: 134-135; Irvine, G.J., et al., 2001. The age of two cratons: a PGE and Os-Isotopic study of peridotite xenoliths from the Jericho kimberlite (Slave craton) and the Somerset Island kimberlite field (Churchill Province). The Slave-Kaapvaal Workshop, Merrickville, Ontario, Canada]. Younger, Paleoproterozoic, TRD model ages for Somerset Island samples are generally interpreted as the result of open system behaviour during metasomatic and/or magmatic processes, with possibly the addition of new lithospheric material during tectono-thermal events related to the Taltson-Thelon orogen. PGE patterns highly depleted in Pt and Pd generally correspond to older Archean TRD model ages indicating closed system behaviour since the time of

  9. A novel adaptive synchronization control of a class of master-slave large-scale systems with unknown channel time-delay

    NASA Astrophysics Data System (ADS)

    Shen, Qikun; Zhang, Tianping

    2015-05-01

    The paper addresses a practical issue for adaptive synchronization in master-slave large-scale systems with constant channel time-delay., and a novel adaptive synchronization control scheme is proposed to guarantee the synchronization errors asymptotically converge to the origin, in which the matching condition as in the related literatures is not necessary. The real value of channel time-delay can be estimated online by a proper adaptation mechanism, which removes the conditions that the channel time-delay should be known exactly as in existing works. Finally, simulation results demonstrate the effectiveness of the approach.

  10. Relationship between Antarctic sea ice and southwest African climate during the late Quaternary

    NASA Astrophysics Data System (ADS)

    Stuut, Jan-Berend W.; Crosta, Xavier; van der Borg, Klaas; Schneider, Ralph

    2004-10-01

    Here we compare late Quaternary southwest African climate records from the west coast of southern Africa (published winter rainfall and trade wind intensity records from a core off the coast of Namibia) to records of Antarctic sea-ice extent. This comparison reveals coherent changes between Antarctic sea-ice extent and the southwest African winter rain region since 45 k.y. B.P., with enhanced winter rainfall and trade-wind vigor during periods of increased sea-ice presence. We propose an oceanic and atmospheric coupling between Antarctic sea ice and the winter rainfall zone of southwest Africa that may lead to increased desertification in the region if global warming persists.

  11. 78 FR 42084 - Cooperative Agreement to Support the World Trade Organization's Standards and Trade Development...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-15

    ... HUMAN SERVICES Food and Drug Administration Cooperative Agreement to Support the World Trade...) to the World Trade Organization's (WTO) Standards and Trade Development Facility (STDF). DATES... partnership established by the Food and Agriculture Organization, World Organization for Animal Health,...

  12. Illegal killing for ivory drives global decline in African elephants.

    PubMed

    Wittemyer, George; Northrup, Joseph M; Blanc, Julian; Douglas-Hamilton, Iain; Omondi, Patrick; Burnham, Kenneth P

    2014-09-09

    Illegal wildlife trade has reached alarming levels globally, extirpating populations of commercially valuable species. As a driver of biodiversity loss, quantifying illegal harvest is essential for conservation and sociopolitical affairs but notoriously difficult. Here we combine field-based carcass monitoring with fine-scale demographic data from an intensively studied wild African elephant population in Samburu, Kenya, to partition mortality into natural and illegal causes. We then expand our analytical framework to model illegal killing rates and population trends of elephants at regional and continental scales using carcass data collected by a Convention on International Trade in Endangered Species program. At the intensively monitored site, illegal killing increased markedly after 2008 and was correlated strongly with the local black market ivory price and increased seizures of ivory destined for China. More broadly, results from application to continental data indicated illegal killing levels were unsustainable for the species between 2010 and 2012, peaking to ∼ 8% in 2011 which extrapolates to ∼ 40,000 elephants illegally killed and a probable species reduction of ∼ 3% that year. Preliminary data from 2013 indicate overharvesting continued. In contrast to the rest of Africa, our analysis corroborates that Central African forest elephants experienced decline throughout the last decade. These results provide the most comprehensive assessment of illegal ivory harvest to date and confirm that current ivory consumption is not sustainable. Further, our approach provides a powerful basis to determine cryptic mortality and gain understanding of the demography of at-risk species.

  13. Trading patients. Lessons from Scandinavia.

    PubMed

    Botten, Grete; Grepperud, Sverre; Nerland, Sölve Mikal

    2004-09-01

    The next few decades will bring about more trade in services, among them health care. This paper describes a recent project on cross-border trading of patients initiated by the Norwegian parliament (The Patient Bridge). This health policy reform met some resistance among hospital physicians. However, patients were willing to participate if being properly informed and supported by local health care workers. The Patient Bridge turned out to be a relatively expensive project partly because of the transaction costs involved (transportation and escort) and partly because of high treatment costs. Excessive treatment costs were a result of insufficient cost-consciousness in the purchasing organization. The Patient Bridge revealed large price differentials not only between Norwegian and foreign hospitals, but also between hospitals abroad, even within the same country. This finding points to the possibilities of reaching mutual gains from trading patients across borders.

  14. A Bibliography of African Languages and Linguistics.

    ERIC Educational Resources Information Center

    Murphy, John D., Comp.; Goff, Harry, Comp.

    The present bibliography of African languages and linguistics includes not only works relating to the "Negro-African" languages, but also those dealing with the African varieties of Arabic, the Hamitic languages, Malagasy, Afrikaans, and various Creoles. (The greater part of the entries relate to the indigenous languages of the African continent…

  15. Spatial Dynamics of the Communities and the Role of Major Countries in the International Rare Earths Trade: A Complex Network Analysis

    PubMed Central

    Wang, Xibo; Ge, Jianping; Wei, Wendong; Li, Hanshi; Wu, Chen; Zhu, Ge

    2016-01-01

    Rare earths (RE) are critical materials in many high-technology products. Due to the uneven distribution and important functions for industrial development, most countries import RE from a handful of suppliers that are rich in RE, such as China. However, because of the rapid growth of RE exploitation and pollution of the mining and production process, some of the main suppliers have gradually tended to reduce the RE production and exports. Especially in the last decade, international RE trade has been changing in the trade community and trade volume. Based on complex network theory, we built an unweighted and weighted network to explore the evolution of the communities and identify the role of the major countries in the RE trade. The results show that an international RE trade network was dispersed and unstable because of the existence of five to nine trade communities in the unweighted network and four to eight trade communities in the weighted network in the past 13 years. Moreover, trade groups formed due to the great influence of geopolitical relations. China was often associated with the South America and African countries in the same trade group. In addition, Japan, China, the United States, and Germany had the largest impacts on international RE trade from 2002 to 2014. Last, some policy suggestions were highlighted according to the results. PMID:27137779

  16. Spatial Dynamics of the Communities and the Role of Major Countries in the International Rare Earths Trade: A Complex Network Analysis.

    PubMed

    Wang, Xibo; Ge, Jianping; Wei, Wendong; Li, Hanshi; Wu, Chen; Zhu, Ge

    2016-01-01

    Rare earths (RE) are critical materials in many high-technology products. Due to the uneven distribution and important functions for industrial development, most countries import RE from a handful of suppliers that are rich in RE, such as China. However, because of the rapid growth of RE exploitation and pollution of the mining and production process, some of the main suppliers have gradually tended to reduce the RE production and exports. Especially in the last decade, international RE trade has been changing in the trade community and trade volume. Based on complex network theory, we built an unweighted and weighted network to explore the evolution of the communities and identify the role of the major countries in the RE trade. The results show that an international RE trade network was dispersed and unstable because of the existence of five to nine trade communities in the unweighted network and four to eight trade communities in the weighted network in the past 13 years. Moreover, trade groups formed due to the great influence of geopolitical relations. China was often associated with the South America and African countries in the same trade group. In addition, Japan, China, the United States, and Germany had the largest impacts on international RE trade from 2002 to 2014. Last, some policy suggestions were highlighted according to the results.

  17. Re-envisioning global agricultural trade: time for a paradigm shift to ensure food security and population health in low-income countries.

    PubMed

    Pirkle, Catherine M; Poliquin, Hélène; Sia, Drissa; Kouakou, Kouassi Joseph; Sagna, Tani

    2015-03-01

    In this commentary, we use examples from West Africa to highlight how the liberalization of global agricultural trade exacerbates population health inequalities by threatening the livelihoods and food security of communities in low-income settings. We highlight the exploitative nature of trade agreements with West African countries demonstrating how these agreements disincentivize local agricultural investment and take jobs away from small-scale farmers. Further, we link agricultural trade liberalization to increased food insecurity, malnutrition, and exposure to environmental contaminants. Finally, we propose a paradigm shift that advocates for food sovereignty and the right to food.

  18. Syllabus in Trade Electricity-Electronics. Section II. Trade Electricity.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Occupational Education Curriculum Development.

    This second section of a three-part syllabus for a flexible curriculum in trade electricity-electronics contains four semi-independent units: (1) Advanced Electricity, (2) Residential and Commercial Wiring, (3) Industrial Electricity, and (4) Motor Controls. Introductory sections describe development of the curriculum, outline the total trade…

  19. Graphic Arts. Trade and Industrial Education Trade Preparatory Training Guide.

    ERIC Educational Resources Information Center

    Nebraska State Dept. of Education, Lincoln. Div. of Vocational Education.

    One of a series of curriculum guides prepared for the graphic communications occupations cluster, this guide identifies the essentials of the graphic arts trade as recommended by the successful printers. An instructional program based upon the implementation of the guide is expected to prepare a student to adequately perform entry level tasks…

  20. Machine Shop. Trade and Industrial Education Trade Preparatory Training Guide.

    ERIC Educational Resources Information Center

    Nebraska State Dept. of Education, Lincoln. Div. of Vocational Education.

    One of a series of curriculum guides prepared for the metal occupations cluster of the construction/fabrication occupational group, this guide identifies the essentials of the machinist trade as recommended by the successful machinist. An instructional program based upon the implementation of this guide is expected to prepare a student to…

  1. Foundry. Trade and Industrial Education Trade Preparatory Training Guide.

    ERIC Educational Resources Information Center

    Nebraska State Dept. of Education, Lincoln. Div. of Vocational Education.

    One of a series of curriculum guides prepared for the metals occupations cluster of the construction/fabrication occupational group, this guide identifies the essentials of the foundry trade as recommended by the successful foundry operator. An instructional program based upon the implementation of the guide is expected to prepare a student to…

  2. Changes in biological productivity along the northwest African margin over the past 20,000 years

    NASA Astrophysics Data System (ADS)

    Bradtmiller, Louisa I.; McGee, David; Awalt, Mitchell; Evers, Joseph; Yerxa, Haley; Kinsley, Christopher W.; deMenocal, Peter B.

    2016-01-01

    The intertropical convergence zone and the African monsoon system are highly sensitive to climate forcing at orbital and millennial timescales. Both systems influence the strength and direction of the trade winds along northwest Africa and thus directly impact coastal upwelling. Sediment cores from the northwest African margin record upwelling-related changes in biological productivity connected to changes in regional and hemispheric climate. We present records of 230Th-normalized biogenic opal and Corg fluxes using a meridional transect of four cores from 19°N-31°N along the northwest African margin to examine changes in paleoproductivity since the last glacial maximum. We find large changes in biogenic fluxes synchronous with changes in eolian fluxes calculated using end-member modeling, suggesting that paleoproductivity and dust fluxes were strongly coupled, likely linked by changes in wind strength. Opal and Corg fluxes increase at all sites during Heinrich Stadial 1 and the Younger Dryas, consistent with an overall intensification of the trade winds, and changes in the meridional flux gradient indicate a southward wind shift at these times. Biogenic fluxes were lowest, and the meridional flux gradients were weakest during the African Humid Period when the monsoon was invigorated due to precessional changes, with greater rainfall and weaker trade winds over northwest Africa. These results expand the spatial coverage of previous paleoproxy studies showing similar changes, and they provide support for modeling studies showing changes in wind strength and direction consistent with increased upwelling during abrupt coolings and decreased upwelling during the African Humid Period.

  3. 31 CFR 500.322 - Authorized trade territory; member of the authorized trade territory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., Lebanon, Macao, Malaysia, Nepal, Oman, Pakistan, Qatar, Saudi Arabia, Singapore, South Korea, Sri Lanka... authorized trade territory. (a) The term authorized trade territory shall include: (1) North, South...

  4. 15 CFR 2002.0 - Trade Policy Committee.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Trade Policy Committee. 2002.0 Section 2002.0 Commerce and Foreign Trade Regulations Relating to Foreign Trade Agreements OFFICE OF THE UNITED STATES TRADE REPRESENTATIVE OPERATION OF COMMITTEES § 2002.0 Trade Policy Committee. (a) The Trade...

  5. Selective breeding: the future of TB management in African buffalo?

    PubMed

    le Roex, N; Berrington, C M; Hoal, E G; van Helden, P D

    2015-09-01

    The high prevalence of bovine tuberculosis (BTB) in African buffalo (Syncerus caffer) in regions of southern African has a negative economic impact on the trade of animals and animal products, represents an ecological threat to biodiversity, and poses a health risk to local communities through the wildlife-cattle-human interface. Test and cull methods may not be logistically feasible in many free-range wildlife systems, and with the presence of co-existing BTB hosts and the limited effectiveness of the BCG vaccine in buffalo, there is a need for alternative methods of BTB management. Selective breeding for increased resistance to BTB in buffalo may be a viable method of BTB management in the future, particularly if genetic information can be incorporated into these schemes. To explore this possibility, we discuss the different strategies that can be employed in selective breeding programmes, and consider the implementation of genetic improvement schemes. We reflect on the suitability of applying this strategy for enhanced BTB resistance in African buffalo, and address the challenges of this approach that must be taken into account. Conclusions and the implications for management are presented.

  6. The African Millennium Villages

    PubMed Central

    Sanchez, Pedro; Palm, Cheryl; Sachs, Jeffrey; Denning, Glenn; Flor, Rafael; Harawa, Rebbie; Jama, Bashir; Kiflemariam, Tsegazeab; Konecky, Bronwen; Kozar, Raffaela; Lelerai, Eliud; Malik, Alia; Modi, Vijay; Mutuo, Patrick; Niang, Amadou; Okoth, Herine; Place, Frank; Sachs, Sonia Ehrlich; Said, Amir; Siriri, David; Teklehaimanot, Awash; Wang, Karen; Wangila, Justine; Zamba, Colleen

    2007-01-01

    We describe the concept, strategy, and initial results of the Millennium Villages Project and implications regarding sustainability and scalability. Our underlying hypothesis is that the interacting crises of agriculture, health, and infrastructure in rural Africa can be overcome through targeted public-sector investments to raise rural productivity and, thereby, to increased private-sector saving and investments. This is carried out by empowering impoverished communities with science-based interventions. Seventy-eight Millennium Villages have been initiated in 12 sites in 10 African countries, each representing a major agroecological zone. In early results, the research villages in Kenya, Ethiopia, and Malawi have reduced malaria prevalence, met caloric requirements, generated crop surpluses, enabled school feeding programs, and provided cash earnings for farm families. PMID:17942701

  7. Restoring a Ruptured Relationship: Barnard College's Caryl Phillips' Senior English Seminar Focuses on Broken International Connections and Culminates with a Trans-Atlantic Journey

    ERIC Educational Resources Information Center

    Keels, Crystal L.

    2004-01-01

    Millions of African people who were captured, kidnapped and shackled for sale as part of the trans-Atlantic slave trade first passed through Cape Coast Castle in Ghana, West Africa. They stepped through the doorway that set them on a horrifying journey across the Atlantic Ocean. Men, women and children were taken by force, leaving their loved…

  8. Proliferation of Small Arms and Light Weapons in West Africa: Implications for Subregional Security

    DTIC Science & Technology

    2007-06-15

    Independence (Arizona: The Oryx Press, 2001), 4. 15Ibid., 1. 16Ibid., 5. 17Ibid., 55. 18Taya Weiss, 7. 19Stephen Akintoye, Emergent African States: Topics...Documentary History from Slave Trade to Independence. Arizona: The Oryx Press, 2001. 78 Articles and Periodicals Amnesty International. “Human Right

  9. Recent Literature on Slavery in Colonial North America.

    ERIC Educational Resources Information Center

    Wright, Donald R.

    2003-01-01

    Provides a review of literature published on slavery in colonial North America, focusing on how this literature has changed over the years. Includes literature in topical areas, such as the Atlantic slave trade, African American culture, and race. Includes a bibliography. (CMK)

  10. A Hand-in-Hand Approach for Security and Development in Sub-Saharan Africa

    DTIC Science & Technology

    2010-06-15

    8 Colonialism In 1885, several years after the slave trade from Africa ended, several European powers met in Berlin to establish frontiers in...enjoyed a positive relationship largely due to the economic and political leadership that Ghana displays. Liberia The history of... Liberia is unique among African nations, notably because of its relationship with the United States. The American Colonization Society founded Liberia

  11. Central African Republic.

    PubMed

    1989-11-01

    The Central African Republic contains 242,000 square miles, which rolling terrain almost 2000 feet above sea level. The climate is tropical, and it has a population of 2.8 million people with a 2.5% growth rate. There are more than 80 ethnic groups including Baya 34%, Banda 28%, Sara 10%, Mandja 9%, Mboum 9%, and M'Baka 7%. The religions are traditional African 35%, protestant 25%, Roman Catholic 25%, and Muslim 15%, and the languages are French and Sangho. The infant mortality rate is 143/1000, with expectancy at 49 years and a 40% literacy rate. The work force of 1 million is 70% agricultural, industry 6% and commerce and service 6% and government 3%. The government consists of a president assisted by cabinet ministers and a single party. Natural resources include diamonds, uranium, timber, gold, and oil, and major industries are beverages, textiles, and soap. Agricultural products feature coffee, cotton, peanuts, tobacco, food crops and livestock. Most of the population live in rural areas and most of the 80 ethnic groups have their own language. This is one of the world's least developed countries, with a per capita income of $375/year. The main problems with development are the poor transportation infrastructure, and the weak internal and international marketing systems. The US and various international organizations have aided in agriculture development, health programs, and family planning. US investment is mainly in diamond and gold mining, and although oil drilling has been successful it is not economically feasible at current prices.

  12. A Modified Implementation of Tristate Inverter Based Static Master-Slave Flip-Flop with Improved Power-Delay-Area Product

    PubMed Central

    Tiwari, Satish Chandra; Gupta, Maneesha

    2014-01-01

    The paper introduces novel architectures for implementation of fully static master-slave flip-flops for low power, high performance, and high density. Based on the proposed structure, traditional C2MOS latch (tristate inverter/clocked inverter) based flip-flop is implemented with fewer transistors. The modified C2MOS based flip-flop designs mC2MOSff1 and mC2MOSff2 are realized using only sixteen transistors each while the number of clocked transistors is also reduced in case of mC2MOSff1. Postlayout simulations indicate that mC2MOSff1 flip-flop shows 12.4% improvement in PDAP (power-delay-area product) when compared with transmission gate flip-flop (TGFF) at 16X capacitive load which is considered to be the best design alternative among the conventional master-slave flip-flops. To validate the correct behaviour of the proposed design, an eight bit asynchronous counter is designed to layout level. LVS and parasitic extraction were carried out on Calibre, whereas layouts were implemented using IC station (Mentor Graphics). HSPICE simulations were used to characterize the transient response of the flip-flop designs in a 180 nm/1.8 V CMOS technology. Simulations were also performed at 130 nm, 90 nm, and 65 nm to reveal the scalability of both the designs at modern process nodes. PMID:24723808

  13. A modified implementation of tristate inverter based static master-slave flip-flop with improved power-delay-area product.

    PubMed

    Singh, Kunwar; Tiwari, Satish Chandra; Gupta, Maneesha

    2014-01-01

    The paper introduces novel architectures for implementation of fully static master-slave flip-flops for low power, high performance, and high density. Based on the proposed structure, traditional C(2)MOS latch (tristate inverter/clocked inverter) based flip-flop is implemented with fewer transistors. The modified C(2)MOS based flip-flop designs mC(2)MOSff1 and mC(2)MOSff2 are realized using only sixteen transistors each while the number of clocked transistors is also reduced in case of mC(2)MOSff1. Postlayout simulations indicate that mC(2)MOSff1 flip-flop shows 12.4% improvement in PDAP (power-delay-area product) when compared with transmission gate flip-flop (TGFF) at 16X capacitive load which is considered to be the best design alternative among the conventional master-slave flip-flops. To validate the correct behaviour of the proposed design, an eight bit asynchronous counter is designed to layout level. LVS and parasitic extraction were carried out on Calibre, whereas layouts were implemented using IC station (Mentor Graphics). HSPICE simulations were used to characterize the transient response of the flip-flop designs in a 180 nm/1.8 V CMOS technology. Simulations were also performed at 130 nm, 90 nm, and 65 nm to reveal the scalability of both the designs at modern process nodes.

  14. Women and Trade Union Education.

    ERIC Educational Resources Information Center

    Holmes, Caroline; Jackson, Judith

    2000-01-01

    Many British unions are failing to attract women members. The General Federal of Trade Unions has begun a women's studies program, offering communication and confidence building, women's history, and other courses that are helping women become involved in union l leadership and decision making. (SK)

  15. India's Trade in Higher Education

    ERIC Educational Resources Information Center

    Kumar, Shailendra

    2015-01-01

    India has had an extremely adverse balance of trade in education. Though only a minor education exporter through Mode 2, India is the world's second largest student-sending country. Nevertheless, given English as the medium of instruction especially in apex institutions, low tuition and cost of living, quite a few world-class institutions, and a…

  16. FOIA: What's a Trade Secret?

    ERIC Educational Resources Information Center

    Hawker, Curtis

    The Freedom of Information Act (FOIA) was amended in 1974 in order to restrict government control and to facilitate the public's access to information. However, part of the FOIA bans federal officials from disclosing "trade secrets" and commercial or financial information obtained in confidential circumstances. This exemption has…

  17. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Bosch, Stephen; Ink, Gary; Lofquist, William S.

    1998-01-01

    Provides data on prices of U.S. and foreign materials; book title output and average prices, 1996 final and 1997 preliminary figures; book sales statistics, 1997--AAP preliminary estimates; U.S. trade in books, 1997; international book title output, 1990-95; book review media statistics; and number of book outlets in the U.S. and Canada. (PEN)

  18. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Sullivan, Sharon G.; Ink, Gary; Grabois, Andrew; Barr, Catherine

    2001-01-01

    Includes six articles that discuss research and statistics relating to the book trade. Topics include prices of U.S. and foreign materials; book title output and average prices; book sales statistics; book exports and imports; book outlets in the U.S. and Canada; and books and other media reviewed. (LRW)

  19. Organ trade using social networks.

    PubMed

    Alrogy, Waleed; Jawdat, Dunia; Alsemari, Muhannad; Alharbi, Abdulrahman; Alasaad, Abdullah; Hajeer, Ali H

    2016-01-01

    Organ transplantation is recognized worldwide as an effective treatment for organ failure. However, due to the increase in the number of patients requiring a transplant, a shortage of suitable organs for transplantation has become a global problem. Human organ trade is an illegal practice of buying or selling organs and is universally sentenced. The aim of this study was to search social network for organ trade and offerings in Saudi Arabia. The study was conducted from June 22, 2015 to February 19, 2016. The search was conducted on Twitter, Google answers, and Facebook using the following terms: kidney for sale, kidneys for sale, liver for sale, kidney wanted, liver wanted, kidney donor, and liver donor. We found a total of 557 adverts on organ trade, 165 (30%) from donors or sellers, and 392 (70%) from recipients or buyers. On Twitter, we found 472 (85%) adverts, on Google answers 61 (11%), and on Facebook 24 (4%). Organ trade is a global problem, and yet it is increasingly seen in many countries. Although the Saudi Center for Organ Transplantation by-laws specifically prohibits and monitors any form of commercial transplantation, it is still essential to enforce guidelines for medical professionals to detect and prevent such criminal acts.

  20. Orion Flight Performance Design Trades

    NASA Technical Reports Server (NTRS)

    Jackson, Mark C.; Straube, Timothy

    2010-01-01

    A significant portion of the Orion pre-PDR design effort has focused on balancing mass with performance. High level performance metrics include abort success rates, lunar surface coverage, landing accuracy and touchdown loads. These metrics may be converted to parameters that affect mass, such as ballast for stabilizing the abort vehicle, propellant to achieve increased lunar coverage or extended missions, or ballast to increase the lift-to-drag ratio to improve entry and landing performance. The Orion Flight Dynamics team was tasked to perform analyses to evaluate many of these trades. These analyses not only provide insight into the physics of each particular trade but, in aggregate, they illustrate the processes used by Orion to balance performance and mass margins, and thereby make design decisions. Lessons learned can be gleaned from a review of these studies which will be useful to other spacecraft system designers. These lessons fall into several categories, including: appropriate application of Monte Carlo analysis in design trades, managing margin in a highly mass-constrained environment, and the use of requirements to balance margin between subsystems and components. This paper provides a review of some of the trades and analyses conducted by the Flight Dynamics team, as well as systems engineering lessons learned.

  1. Trade in the Pacific Rim.

    ERIC Educational Resources Information Center

    Dollar, David

    1988-01-01

    States that international trade is a prime factor linking the Pacific Rim nations. Discusses the differences in each nation's productive factors (land, labor, capital) and examines the emerging technological competition. Concludes that if U.S. firms cannot meet the challenge of foreign competition, then protectionism might limit further economic…

  2. Hormesis, hotspots and emissions trading.

    PubMed

    Wiener, Jonathan B

    2004-06-01

    Instrument choice--the comparison of technology standards, performance standards, taxes and tradable permits--has been a major topic in environmental law and environmental economics. Most analyses assume that emissions and health effects are positively and linearly related. If they are not, this complicates the instrument choice analysis. This article analyses the effects of a nonlinear dose-response function on instrument choice. In particular, it examines the effects of hormesis (high-dose harm but low-dose benefit) on the choice between fixed performance standards and tradable emissions permits. First, the article distinguishes the effects of hormesis from the effects of local emissions. Hormesis is an attribute of the dose-response or exposure-response relationship. Hotspots are an attribute of the emissions-exposure relationship. Some pollutants may be hormetic and cause local emissions-exposure effects; others may be hormetic without causing local emissions-exposure effects. It is only the local exposure effects of emissions that pose a problem for emissions trading. Secondly, the article shows that the conditions under which emissions trading would perform less well or even perversely under hormesis, depend on how stringent a level of protection is set. Only when the regulatory standard is set at the nadir of the hormetic curve would emissions trading be seriously perverse (assuming other restrictive conditions as well), and such a standard is unlikely. Moreover, the benefits of the overall programme may justify the risk of small perverse effects around this nadir. Thirdly, the article argues that hotspots can be of concern for two distinct reasons, harmfulness and fairness. Lastly, the paper argues that the solution to these problems may not be to abandon market-based incentive instruments and their cost-effectiveness gains, but to improve them further by moving from emissions trading and emissions taxes to risk trading and risk taxes. In short, the article

  3. Health Care Experiences and Perceived Barriers to Health Care Access: A Qualitative Study Among African Migrants in Guangzhou, Guangdong Province, China

    PubMed Central

    Brown, Katherine B.; Yu, Fan; Yang, Jingqi; Wang, Jason; Schrock, Joshua M.; Bodomo, Adams B.; Yang, Ligang; Yang, Bin; Nehl, Eric J.; Tucker, Joseph D.; Wong, Frank Y.

    2014-01-01

    Guangzhou, one of China's largest cities and a main trading port in South China, has attracted many African businessmen and traders migrating to the city for financial gains. Previous research has explored the cultural and economic roles of this newly emerging population; however, little is known about their health care experiences while in China. Semi-structured interviews and focus groups were used to assess health care experiences and perceived barriers to health care access among African migrants in Guangzhou, China. Overall, African migrants experienced various barriers to accessing health care and were dissatisfied with local health services. The principal barriers to care reported included affordability, legal issues, language barriers, and cultural differences. Facing multiple barriers, African migrants have limited access to care in Guangzhou. Local health settings are not accustomed to the African migrant population, suggesting that providing linguistically and culturally appropriate services may improve access to care for the migrants. PMID:25294415

  4. Health Care Experiences and Perceived Barriers to Health Care Access: A Qualitative Study Among African Migrants in Guangzhou, Guangdong Province, China.

    PubMed

    Lin, Lavinia; Brown, Katherine B; Yu, Fan; Yang, Jingqi; Wang, Jason; Schrock, Joshua M; Bodomo, Adams B; Yang, Ligang; Yang, Bin; Nehl, Eric J; Tucker, Joseph D; Wong, Frank Y

    2015-10-01

    Guangzhou, one of China's largest cities and a main trading port in South China, has attracted many African businessmen and traders migrating to the city for financial gains. Previous research has explored the cultural and economic roles of this newly emerging population; however, little is known about their health care experiences while in China. Semi-structured interviews and focus groups were used to assess health care experiences and perceived barriers to health care access among African migrants in Guangzhou, China. Overall, African migrants experienced various barriers to accessing health care and were dissatisfied with local health services. The principal barriers to care reported included affordability, legal issues, language barriers, and cultural differences. Facing multiple barriers, African migrants have limited access to care in Guangzhou. Local health settings are not accustomed to the African migrant population, suggesting that providing linguistically and culturally appropriate services may improve access to care for the migrants.

  5. ILLICIT CIGARETTE TRADE IN THAILAND

    PubMed Central

    Pavananunt, Pirudee

    2012-01-01

    The sale and consumption of illicit tobacco increases consumption, impacts public health, reduces tax revenue and provides an argument against tax increases. Thailand has some of the best tobacco control policies in Southeast Asia with one of the highest tobacco tax rates, but illicit trade has the potential to undermine these policies and needs investigating. Two approaches were used to assess illicit trade between 1991 and 2006: method 1, comparison of tobacco used based on tobacco taxes paid and survey data, and method 2, discrepancies between export data from countries exporting tobacco to Thailand and Thai official data regarding imports. A three year average was used to smooth differences due to lags between exports and imports. For 1991–2006, the estimated manufactured cigarette consumption from survey data was considerably lower than sales tax paid, so method 1 did not provide evidence of cigarette tax avoidance. Using method 2 the trade difference between reported imports and exports, indicates 10% of cigarettes consumed in Thailand (242 million packs per year) between 2004 and 2006 were illicit. The loss of revenue amounted to 4,508 million Baht (2002 prices) in the same year, that was 14% of the total cigarette tax revenue. Cigarette excise tax rates had a negative relationship with consumption trends but no relation with the level of illicit trade. There is a need for improved policies against smuggling to combat the rise in illicit tobacco consumption. Regional coordination and implementation of protocols on illicit trade would help reduce incentives for illegal tax avoidance. PMID:22299425

  6. African Passages: Journaling through Archetypes.

    ERIC Educational Resources Information Center

    Spencer, Patricia

    1990-01-01

    Explores how students (through an awareness of literary archetypes and journal writing) can use African stories to cross cultures, time, and continents, making connections between their worlds and the worlds of others. (MG)

  7. Early African Hominids: Pedagogic Patterns.

    ERIC Educational Resources Information Center

    Newman, James L.

    1984-01-01

    By studying early African hominids, students can learn about the interactive testing and creative aspects of scientific thinking and sharpen their geographical skills. It is impossible to study this topic without giving prominence to space and time. (RM)

  8. African-Americans and Alzheimer's

    MedlinePlus

    ... African-Americans are at a higher risk for Alzheimer's disease. Many Americans dismiss the warning signs of Alzheimer's, ... two times more likely to develop late-onset Alzheimer's disease than whites and less likely to have a ...

  9. 77 FR 25678 - International Trade Administration

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Antidumping or Countervailing Duty Order, Finding, or Suspended Investigation; Advance Notification of Sunset Reviews AGENCY: Import Administration, International Trade...

  10. EPA Webinar on Emissions Trading 101

    EPA Pesticide Factsheets

    Presentation offering a basic overview of emissions trading, an explanation of common terms (including budgets, set-asides, etc.), a general description of how mass-based and rate-based trading works, and a discussion of tools and resources.

  11. Global trade in satellites and launch services

    NASA Astrophysics Data System (ADS)

    Hearing before the Subcommittee on Space of the Committee on Science, Space, and Technology of the House of Representatives is presented. Written testimony, submittals for the record, and responses to written questions are included. Topics concerning the global trade in satellites and launch services include foreign competition, the China and Russia trade agreements, Commerce licensing on international sales and export, trade control, technology transfer, satellite communications and the economy, satellites and the global information infrastructure, commercial space revenues, and enforcement of trade policies.

  12. Emissions trading: principles and practice. 2nd

    SciTech Connect

    Tietenberg, T.H.

    2006-02-15

    The author demonstrates how emissions trading became an attractive alternative to command-and-control policies that would have required the EPA to disallow the opening of new plants in the middle of the recession-burdened 1970s. His examination of the evolution of this system includes, among other applications, the largest multinational trading system ever conceived, the European Union's Greenhouse Gas Emission Trading Scheme (EUETG), and the use of emissions trading in the Kyoto Protocol.

  13. World Trade Organization activity for health services.

    PubMed

    Gros, Clémence

    2012-01-01

    Since the establishment of a multilateral trading system and the increasing mobility of professionals and consumers of health services, it seems strongly necessary that the World Trade Organization (WTO) undertakes negotiations within the General Agreement on Trade in Services (GATS), and that WTO's members attempt to reach commitments for health-related trade in services. How important is the GATS for health policy and how does the GATS refer to health services? What are the current negotiations and member's commitments?

  14. Hepatitis C in African Americans.

    PubMed

    Saab, Sammy; Jackson, Christian; Nieto, Jose; Francois, Fritz

    2014-10-01

    The care of hepatitis C virus (HCV) in African Americans represents an opportunity to address a major health disparity in medicine. In all facets of HCV infection, African Americans are inexplicably affected, including in the prevalence of the virus, which is higher among them compared with most of the racial and ethnic groups. Ironically, although fibrosis rates may be slow, hepatocellular carcinoma and mortality rates appear to be higher among African Americans. Sustained viral response (SVR) rates have historically significantly trailed behind Caucasians. The reasons for this gap in SVR are related to both viral and host factors. Moreover, low enrollment rates in clinical trials hamper the study of the efficacy of anti-viral therapy. Nevertheless, the gap in SVR between African Americans and Caucasians may be narrowing with the use of direct-acting agents. Gastroenterologists, hepatologists, primary care physicians, and other health-care providers need to address modifiable risk factors that affect the natural history, as well as treatment outcomes, for HCV among African Americans. Efforts need to be made to improve awareness among health-care providers to address the differences in screening and referral patterns for African Americans.

  15. Sahel megadrought during Heinrich Stadial 1: evidence for a three-phase evolution of the low- and mid-level West African wind system

    NASA Astrophysics Data System (ADS)

    Bouimetarhan, Ilham; Prange, Matthias; Schefuß, Enno; Dupont, Lydie; Lippold, Jörg; Mulitza, Stefan; Zonneveld, Karin

    2012-12-01

    Millennial-scale dry events in the Northern Hemisphere monsoon regions during the last Glacial period are commonly attributed to southward shifts of the Intertropical Convergence Zone (ITCZ) associated with an intensification of the northeasterly (NE) trade wind system during intervals of reduced Atlantic meridional overturning circulation (AMOC). Through the use of high-resolution last deglaciation pollen records from the continental slope off Senegal, our data show that one of the longest and most extreme droughts in the western Sahel history, which occurred during the North Atlantic Heinrich Stadial 1 (HS1), displayed a succession of three major phases. These phases progressed from an interval of maximum pollen representation of Saharan elements between ˜19 and 17.4 kyr BP indicating the onset of aridity and intensified NE trade winds, followed by a millennial interlude of reduced input of Saharan pollen and increased input of Sahelian pollen, to a final phase between ˜16.2 and 15 kyr BP that was characterized by a second maximum of Saharan pollen abundances. This change in the pollen assemblage indicates a mid-HS1 interlude of NE trade wind relaxation, occurring between two distinct trade wind maxima, along with an intensified mid-tropospheric African Easterly Jet (AEJ) indicating a substantial change in West African atmospheric processes. The pollen data thus suggest that although the NE trades have weakened, the Sahel drought remained severe during this time interval. Therefore, a simple strengthening of trade winds and a southward shift of the West African monsoon trough alone cannot fully explain millennial-scale Sahel droughts during periods of AMOC weakening. Instead, we suggest that an intensification of the AEJ is needed to explain the persistence of the drought during HS1. Simulations with the Community Climate System Model indicate that an intensified AEJ during periods of reduced AMOC affected the North African climate by enhancing moisture

  16. How unique is the Udachnaya-East kimberlite? Comparison with kimberlites from the Slave Craton (Canada) and SW Greenland

    NASA Astrophysics Data System (ADS)

    Kamenetsky, Vadim S.; Kamenetsky, Maya B.; Weiss, Yakov; Navon, Oded; Nielsen, Troels F. D.; Mernagh, Terrence P.

    2009-11-01

    The origin of alkali carbonates and chlorides in the groundmass of unaltered Udachnaya-East kimberlites in Siberia is still controversial. Contrary to existing dogma that the Udachnaya-East kimberlite was either contaminated by the crustal sediments or platform brines, magmatic origin of the groundmass assemblage has been proposed on the basis of melt immiscibility textures, melt inclusion studies, and strontium and neon isotope compositions. We further tested the idea of alkali- and chlorine enrichment of the kimberlite parental melt by studying olivine-hosted melt inclusions and secondary serpentine in kimberlites from the Slave Craton, Canada (Gahcho Kué, Jericho, Aaron and Leslie pipes) and southern West Greenland (Majuagaa dyke). Host olivine phenocrysts closely resemble groundmass olivine from the Udachnaya-East kimberlite in morphology, compositions (high-Fo, low-Ca), complex zoning with cores of varying shapes and compositions and rims of constant Fo. Melt inclusions in olivine consist of several translucent and opaque daughter phases and vapour bubble(s). The daughter crystals studied in unexposed inclusions by laser Raman spectroscopy and in carefully exposed inclusions by WDS-EDS are represented by Na-K chlorides, calcite, dolomite, magnesite, Ca-Na, Ca-Na-K and Ca-Mg-Ba carbonates, bradleyite Na 3 Mg(CO 3)(PO 4), K-bearing nahpoite Na 2(HPO 4), apatite, phlogopite and tetraferriphlogopite, unidentified sulphates, Fe sulphides, djerfisherite, pyrochlore (Na,Ca) 2Nb 2O 6(OH,F), monticellite, Cr-spinel and Fe-Ti oxides. High abundances of Na, K (e.g., (Na + K)/Ca = 0.15-0.85) and incompatible trace elements in the melt inclusions are confirmed by LA-ICPMS analysis of individual inclusions. Heating experiments show that melting of daughter minerals starts and completes at low temperatures (~ 100 °C and 600 °C, respectively), further reinforcing the similarity with the Udachnaya-East kimberlite. Serpentine minerals replacing olivine in some of the studied

  17. The nature of Mesoarchaean seawater and continental weathering in 2.85 Ga banded iron formation, Slave craton, NW Canada

    NASA Astrophysics Data System (ADS)

    Haugaard, Rasmus; Ootes, Luke; Creaser, Robert A.; Konhauser, Kurt O.

    2016-12-01

    Banded iron formations (BIF) have been extensively used as proxies to infer the chemical composition of ancient bulk seawater. However, their proximity to ancient crust suggests that they might also be used to reveal the composition of emergent continental landmass at the time of their deposition. Here we use the combination of geochemistry and Sm-Nd isotopes on a layer-by-layer basis to interpret the relative contributions of hydrothermal, hydrogenous and terrestrial input to one of the oldest documented Superior-type BIF in the world. The ∼2.85 Ga Central Slave Cover Group BIF is deposited within a rift basin related to a continental margin and is found associated with basement gneisses, as well as shoreline and shallow-shelf type facies, such as fuchsitic quartzite and pebble-to-cobble conglomerate, that confirm a near-shore depositional setting for the BIF. The BIF ranges from a pure chemical oxide (magnetite)-silicate (grunerite + actinolite) sediment with low Al2O3 (<1 wt.%) into a mixture of chemical and clastic sediment characterized by higher Al2O3 (⩽10 wt.%) and the occurrence of ferro-hornblende, biotite and garnet. The silica bands have low trace metal content (e.g., Ni), low ∑REE (average of 6 ppm) and a shale-normalized rare earth and yttrium (REY) pattern that is HREE-to-LREE enriched with (Pr/Yb)SN values reaching <0.2. The iron bands are more enriched, with average ∑REE of 26 and with a more uniform and less fractionated REY pattern (average (Pr/Yb)SN of 0.5). During active rifting of the basement, excess of Eu2+ impacted the basin yielding seawater with Eu anomalies [(Eu/Eu∗)SN] as high as 3.85 (average 2.75), larger than similarly-aged BIF. High-resolution geochemistry shows that there is more silica (19.4 wt.% SiO2) in the iron bands than iron (8.7 wt.% Fe2O3) in the silica bands, implying that dissolved Fe2+ came to the BIF site in pulses and that silica likely represents background deposition. Consistently radiogenic εNd(t) values

  18. ETUDE - European Trade Union Distance Education.

    ERIC Educational Resources Information Center

    Creanor, Linda; Walker, Steve

    2000-01-01

    Describes transnational distance learning activities among European trade union educators carried out as part of the European Trade Union Distance Education (ETUDE) project, supported by the European Commission. Highlights include the context of international trade union distance education; tutor training course; tutors' experiences; and…

  19. 77 FR 31151 - World Trade Week, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ... 8827 of May 21, 2012 World Trade Week, 2012 By the President of the United States of America A... services designed and produced by Americans. During World Trade Week, we reaffirm the essential role... Week. I encourage all Americans to observe this week with events, trade shows, and educational...

  20. 76 FR 29139 - World Trade Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-19

    ...#0;#0; ] Proclamation 8677 of May 13, 2011 World Trade Week, 2011 By the President of the United... interdependent. World Trade Week is a time to highlight the vital connection between the global economy and the... hereby proclaim May 15 through May 21, 2011, as World Trade Week. I encourage all Americans to...