University of Nebraska Omaha

About: University of Nebraska Omaha is a education organization based out in Omaha, Nebraska, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 4526 authors who have published 8905 publications receiving 213914 citations. The organization is also known as: UNO & University of Omaha.

Theoretical and practical complexity of modeling methods

Abstract: Highlighting the importance of taking into account typical usage when estimating the complexity of a systems development method

Global Diffusion of the Internet - I: India: Is the Elephant Learning to Dance?

Abstract: With his proclamation in 1998 that "IT is India's tomorrow", Prime Minister Vajpayee captured a vision of a 21 st century India substantially different from that of the previous century, with its high levels of poverty, bloated bureaucracies, and protectionist policies. He envisioned the new India as a major IT power, fully integrated with the global economy, bringing about substantial domestic and international benefit. The Internet is a key to this vision, both as an enabler of technologybased change, and as an indicator of the vision's fulfillment. Using an analytic framework developed by the authors and others, this study documents the growth of the Internet in India, from the pre-Internet networks through the boom of the Internet from 1998 to 2003. The Indian experience provides an example of how fundamental, focused changes in policy and legislation can unleash forces that accelerate Internet diffusion. Private sector initiatives greatly expanded the Internet infrastructure and Internet services market. At the same time, government initiatives promoted the expansion of the Internet into parts of the country not well served by private ISPs. Poverty and limited telecommunications infrastructure currently limit the rate and extent of Internet expansion. However, time is an ally; the basic elements for continued growth of the Internet are largely in place.

ChemChains: A platform for simulation and analysis of biochemical networks aimed to laboratory scientists

Abstract: New mathematical models of complex biological structures and computer simulation software allow modelers to simulate and analyze biochemical systems in silico and form mathematical predictions. Due to this potential predictive ability, the use of these models and software has the possibility to compliment laboratory investigations and help refine, or even develop, new hypotheses. However, the existing mathematical modeling techniques and simulation tools are often difficult to use by laboratory biologists without training in high-level mathematics, limiting their use to trained modelers. We have developed a Boolean network-based simulation and analysis software tool, ChemChains, which combines the advantages of the parameter-free nature of logical models while providing the ability for users to interact with their models in a continuous manner, similar to the way laboratory biologists interact with laboratory data. ChemChains allows users to simulate models in an automatic fashion under tens of thousands of different external environments, as well as perform various mutational studies. ChemChains combines the advantages of logical and continuous modeling and provides a way for laboratory biologists to perform in silico experiments on mathematical models easily, a necessary component of laboratory research in the systems biology era.

Broadband neurophysiological abnormalities in the medial prefrontal region of the default-mode network in adults with ADHD.

Abstract: Previous investigations of the default-mode network (DMN) in persons with attention-deficit/hyperactivity disorder (ADHD) have shown reduced functional connectivity between the anterior and posterior aspects. This finding was originally demonstrated in adults with ADHD, then in youth with ADHD, and has been tentatively linked to ultra low frequency oscillations within the DMN. The current study evaluates the specificity of DMN abnormalities to neuronal oscillations in the ultra low frequency range, and examines the regional specificity of these DMN aberrations in medicated and unmedicated adults with, and those without ADHD. An individually matched sample of adults with and without ADHD completed 6-minute sessions of resting-state magnetoencephalography (MEG). Participants with ADHD were known responders to stimulant medications and completed two sessions (predrug/postdrug). MEG data were coregistered to the participant's MRI, corrected for head motion, fitted to a regional-level source model, and subjected to spectral analyses to extract neuronal population activity in regions of the DMN. The unmedicated adults with ADHD exhibited broadband deficits in medial prefrontal cortices (MPFC), but not other DMN regions compared to adults without ADHD. Unmedicated patients also showed abnormal cross-frequency coupling in the gamma range between the MPFC and posterior cingulate areas, and disturbed balance within the DMN as activity in posterior regions was stronger than frontal regions at beta and lower frequencies, which dissipated at higher γ-frequencies. Administration of pharmacotherapy significantly increased prefrontal alpha activity (8-14 Hz) in adults with ADHD, and decreased the cross-frequency gamma coupling. These results indicate that neurophysiological aberrations in the DMN of patients with ADHD are not limited to ultra slow oscillations, and that they may be primarily attributable to abnormal broadband activity in the MPFC.