We present the first oxygen fugacity (fO) 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 fO, 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 SiO-undersaturated magmas.
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http://dx.doi.org/10.1038/s41598-017-00049-3 | DOI Listing |
Wonder exalts its object. Can it also degrade? This question was a central interpretive tension guiding the author's archival research and analysis when he set out to write his first book almost 30 years ago, about a 19th-century woman who was simultaneously degraded-for her race, her disability, her old age, and her enslavement-and lionized for the stories she had to tell and for the symbolism of her very existence. The author reflects on how his fascination with the story he was recovering in the archives reflected his "positionality," or the ways in which his social identity shaped his understanding.
View Article and Find Full Text PDFHeliyon
September 2024
Department of Electrical and Electronics Engineering, Shiraz University of Technology, Shiraz, Iran.
Distributed control is an effective method to coordinate the microgrid with various components, and also in a smart microgrid, communication graph layouts are essential since changing the topology unexpectedly could disrupt the operation of the distributed controllers, and also an imbalance may occur between the production and load. Hence, reducing the exchanged data between units and system operator is essential in order to reduce the transmitted data volume and computational burden. For this purpose, an islanded microgrid with multiple agents which is using cloud-fog computing is proposed here, in order to reduce the computing burden on the central control unit as well as reducing data exchange among units.
View Article and Find Full Text PDFJ Hist Med Allied Sci
September 2024
Binghamton University, New York, USA.
In 1804, Cuban physician Tomás Romay tried and failed to create the first yellow fever vaccine. The article analyzes his experimental efforts, foregrounding the enslaved and enlisted subjects at the center of this early vaccine trial. Though a scientific failure, this brief experiment, the desires and logics embedded within it, and the measures deployed in its wake - in the form of European whitening campaigns - allow us to consider the political uses of immunity during the Age of Atlantic Revolutions.
View Article and Find Full Text PDFInt J Med Robot
August 2024
Lab of Locomotion Bioinspiration and Intelligent Robots, College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China.
Background: Master-slave remote control technology allows patients to be treated promptly during transport and also reduces the risk of contagious infections. Endotracheal intubation, guided by endoscopy and a master-slave system, enables doctors to perform the procedure efficiently and accurately.
Methods: In this paper, we present the development of a master-slave controlled endotracheal intubation robot (EIR).
Demography
June 2024
Department of Experimental Statistics, Louisiana State University, Baton Rouge, LA, USA.
Despite the persistence of relationships between historical racist violence and contemporary Black-White inequality, research indicates, in broad strokes, that the slavery-inequality relationship in the United States has changed over time. Identifying the timing of such change across states can offer insights into the underlying processes that generate Black-White inequality. In this study, we use integrated nested Laplace approximation models to simultaneously account for spatial and temporal features of panel data for Southern counties during the period spanning 1900 to 2018, in combination with data on the concentration of enslaved people from the 1860 census.
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