A new face on the countryside: Indians and colonists in the Southeastern forest (ecology, environment, Virginia, North Carolina, South Carolina)

Using ecological literature and an ethnohistorical approach, this dissertation examines the nature and extent of environmental change resulting from European colonization in Virginia, the Carolinas, and Georgia.;European explorers in the Southeast saw mixed hardwood forests, pinelands, savannahs, marshlands, and inland swamps. These diverse habitats were home to an infinite variety of wildlife, including whitetailed deer, black bears, wild turkeys, buffalo, elk, and beaver. The landscape had been shaped by long-term ecological change and by varying patterns of topography, rainfall, and fire.;The environment had also been altered by Indians. Southeastern Indians were neither despoilers nor conservators of nature. Seeking subsistence and survival, they fished, farmed, hunted, and periodically burned the woods, all of which affected the various ecosystems.;Early contact between natives and Europeans introduced Old World diseases into the Southeast which killed Indians by the thousands. With their culture torn apart by depopulation, the natives ensured their survival by finding a place within the European system. Indians willingly supplied colonists with animal skins, meat, and medicinal plants, a systematic trade which led to the extinction of buffalo and elk and nearly wiped out beaver, deer, and ginseng.;Agricultural clearing by colonists reshaped local climates. Selective cutting of white and live oak, white cedar, and baldcypress made those trees scarce in settled regions. Naval stores production reduced sizeable tracts of pinelands to patches of scrubby hardwoods.;Commercial agriculture exhausted and eroded soils. Domestic animals destroyed native grasses and woody plants. European grasses and weeds, carried by transplanted livestock, replaced indigenous species. Agriculture and ranching simplified existing relationships between plants and animals, creating an ecologically unstable new South. .;Attributing such changes solely to European capitalism is an oversimplification. Since his arrival in North America, man has been alienated from nature. The innovations of a capitalist economy triggered complex cultural interaction between Indians, colonists, slaves, and the land itself, a dialectic which pushed all three groups toward exploitation of the environment

Learning and Transfer of Modulated Locomotor Controllers

We study a novel architecture and training procedure for locomotion tasks. A high-frequency, low-level "spinal" network with access to proprioceptive sensors learns sensorimotor primitives by training on simple tasks. This pre-trained module is fixed and connected to a low-frequency, high-level "cortical" network, with access to all sensors, which drives behavior by modulating the inputs to the spinal network. Where a monolithic end-to-end architecture fails completely, learning with a pre-trained spinal module succeeds at multiple high-level tasks, and enables the effective exploration required to learn from sparse rewards. We test our proposed architecture on three simulated bodies: a 16-dimensional swimming snake, a 20-dimensional quadruped, and a 54-dimensional humanoid. Our results are illustrated in the accompanying video at https://youtu.be/sboPYvhpraQComment: Supplemental video available at https://youtu.be/sboPYvhpra

The glycoprotein IIb/IIIa antagonist c7E3 inhibits platelet aggregation in the presence of heparin-associated antibodies

AbstractPurpose: Heparin-associated antibodies (HAAb), in the presence of heparin, can cause platelet activation and aggregation. The purpose of this study was to assess whether a platelet glycoprotein (GP) IIb/IIIa receptor antagonist, c7E3, would inhibit platelet aggregation in the presence of HAAb. If aggregation is inhibited by c7E3, enzyme-linked immunosorbent assays (ELISA) would be done to determine whether c7E3 interfered with the binding of heparin and the HAAb.Methods: HAAb-positive plasmas from 21 patients (determined by platelet aggregation assays) were studied. Normal donor platelet-rich plasmas (PRP) were incubated (1 minute) with either saline solution or 3 μg/ml of c7E3. Platelet-poor plasma from patients with HAAb and one of three sources of heparin (25 μl, 10 U/ml; porcine heparin, bovine heparin, and low molecular weight heparin [enoxaparin]) were added to the PRP mixture. Aggregation was determined using a platelet aggregometer by measuring time to aggregation, the slope of the aggregation curve, and the percent change in optical density.Results: Platelet aggregation occured in 100%, 100%, and 95% of the saline solution incubations exposed to porcine heparin, bovine heparin, and enoxaparin, respectively. Incubation with c7E3 caused 100% inhibition of platelet aggregation in plasma exposed to porcine heparin, bovine heparin, and enoxaparin. The optical density curves obtained from the ELISA, which were dependent on the binding of HAAb to heparin, were not significantly different when c7E3 was compared to buffer alone.Conclusions: The GP IIb/IIIa receptor antagonist, c7E3, inhibits HAAb-induced platelet aggregation via a mechanism that does not appear to interfere with the binding between heparin and HAAb. Clinical trials are warranted to assess whether GP IIb/IIIa antagonists may allow patients with HAAb to safely receive heparin. (J Vasc Surg 1997;25:124-30.

Southern Federalists And The French Crisis: 1789-1800

This thesis centers on the opinions of nine southern Federalists from Virginia, North Carolina, and South Carolina