12 research outputs found
EEG dynamical correlates of focal and diffuse causes of coma
Background: Rapidly determining the causes of a depressed level of consciousness (DLOC) including coma is a common clinical challenge. Quantitative analysis of the electroencephalogram (EEG) has the potential to improve DLOC assessment by providing readily deployable, temporally detailed characterization of brain activity in such patients. While used commonly for seizure detection, EEG-based assessment of DLOC etiology is less well-established. As a first step towards etiological diagnosis, we sought to distinguish focal and diffuse causes of DLOC through assessment of temporal dynamics within EEG signals. Methods: We retrospectively analyzed EEG recordings from 40 patients with DLOC with consensus focal or diffuse culprit pathology. For each recording, we performed a suite of time-series analyses, then used a statistical framework to identify which analyses (features) could be used to distinguish between focal and diffuse cases. Results: Using cross-validation approaches, we identified several spectral and non-spectral EEG features that were significantly different between DLOC patients with focal vs. diffuse etiologies, enabling EEG-based classification with an accuracy of 76%. Conclusions: Our findings suggest that DLOC due to focal vs. diffuse injuries differ along several electrophysiological parameters. These results may form the basis of future classification strategies for DLOC and coma that are more etiologically-specific and therefore therapeutically-relevant. Electronic supplementary material The online version of this article (doi: 10.1186/s12883-017-0977-0) contains supplementary material, which is available to authorized users
African Americans and Land Loss in Texas: Government Duplicity and Discrimination Based on Race and Class
African American Farmers and Land Loss in Texas, surveys the ways that discrimination at the local, state, and national levels constrained minority farmers during the twentieth century. It considers the characteristics of small-scale farming that created liabilities for landowners regardless of race, including state and federal programs that favored commercial and agribusiness interests. In addition to economic challenges African American farmers had to negotiate racism in the Jim Crow South. The Texas Agricultural Extension Service, the state branch of the USDA\u27s Extension Service, segregated in 1915. The Negro division gave black farmers access to information about USDA programs, but it emphasized their subordinate position relative to white farmers. The Civil Rights Act of 1964 did not reverse decades of racial discrimination. Instead, USDA officials relied on federalism, a theory as old as the Constitution, to justify their tolerance of civil rights violations in Texas and elsewhere. Then, special needs legislation passed during the 1970s and 1980s did not realize its potential to serve ethnically diverse and economically disadvantaged rural Texans. Discrimination based on race combined with a bias toward commercial production. This crippled most black farmers and led to their near extinction