A Case for Symbolic/Sub-symbolic Hybrids

This paper considers the question of what qualities are necessary for an AI system to be a hybrid of symbolic and sub-symbolic approaches. Definitions of symbolic and sub-symbolic systems are given. SCALIR, a hybrid system for information retrieval, is presented, and then used to show how both symbolic and sub-symbolic processing can be combined. Arguments against SCALIR's hybrid nature are presented and rejected

Empirical entropic contributions in computational docking: Evaluation in APS reductase complexes

The results from reiterated docking experiments may be used to evaluate an empirical vibrational entropy of binding in ligand–protein complexes. We have tested several methods for evaluating the vibrational contribution to binding of 22 nucleotide analogues to the enzyme APS reductase. These include two cluster size methods that measure the probability of finding a particular conformation, a method that estimates the extent of the local energetic well by looking at the scatter of conformations within clustered results, and an RMSD-based method that uses the overall scatter and clustering of all conformations. We have also directly characterized the local energy landscape by randomly sampling around docked conformations. The simple cluster size method shows the best performance, improving the identification of correct conformations in multiple docking experiments. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2008Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/60220/1/20936_ftp.pd

Seymour Aquifer Water Quality Improvement Project Final Report

The Seymour Aquifer is a shallow aquifer underlying over 300,000 acres in 20 counties in northwest central Texas. High nitrate concentrations are widespread in the Seymour Aquifer. Median nitrate levels in Knox, Haskell, Baylor, Hall, Wichita, Wilbarger, and Fisher counties exceeded the federal safe drinking water standard (10 mg/L NO3-N). This high concentration is a concern because although 90% of the water pumped from the aquifer is used for irrigation, it is also used as a municipal water source for the communities of Vernon, Burkburnett, and Electra and rural families in the region. To address this threat, the Texas State Soil and Water Conservation Board (TSSWCB), with 319(h) grant funding provided by the Environmental Protection Agency (EPA), worked cooperatively with the Haskell, Wichita-Brazos, and California Creek Soil and Water Conservation Districts (SWCDs); U.S. Department of Agriculture - Natural Resources Conservation Service (NRCS); Texas AgriLife Extension Service (AgriLife Extension); Texas A&M AgriLife – Texas Water Resources Institute (TWRI); Rolling Plains Groundwater Conservation District; and Texas AgriLife Research (AgriLife Research) to encourage the installation of subsurface drip irrigation (SDI) systems and other best management practices (BMPs) to improve water quality (i.e. reduce nitrate) and increase water quantity in the Seymour Aquifer. The project provided technical and financial assistance to producers to implement SDI and other BMPs, education programs and demonstrations of methods for reducing nitrate infiltration and improving irrigation efficiency and an evaluation of the effectiveness of SDI implementation. Considerable interest has been generated in SDI and other more efficient irrigation methods through the efforts of project partners. Through technical and financial assistance provided by the project through the TSSWCB and Haskell, Wichita-Brazos and California Creek SWCDs, 17 producers installed SDI systems on over 1,000 acres. In addition, irrigation management was implemented through the Water Quality Management Plans (WQMPs) developed on over 1,800 acres and nutrient management was implemented on over 2,500 acres. NRCS also began funding irrigation improvements in Haskell, Knox, Baylor, Wilbarger, Hardeman and Foard counties through the Seymour Aquifer Special Emphasis Area. Since this Special Emphasis Area was established in 2004, over $16 million dollars have been provided. In addition to implementing BMPs, a very important component of this project was conducting educational programs and demonstrations. Through seven programs conducted between 2005 and 2008, AgriLife Research and AgriLife Extension provided educational programs and demonstrations on nutrient management and irrigation management to 671 participants. The establishment of the permanent SDI demonstration site at the Chillicothe Station will ensure that these programs are sustained for many years to come and offer producers in the Texas Rolling Plains additional crop production options to enhance economic returns and water quality, and improve their quality of life

Improved Evolutionary Hybrids for Flexible Ligand Docking in Autodock

In this paper we evaluate the design of the hybrid evolutionary algorithms (EAs) that are currently used to perform flexible ligand binding in the Autodock docking software. Hybrid EAs incorporate specialized operators that exploit domain-specific features to accelerate an EA's search. We consider hybrid EAs that use an integrated local search operator to reline individuals within each iteration of the search. We evaluate several factors that impact the efficacy of a hybrid EA, and we propose new hybrid EAs that provide more robust convergence to low-energy docking configurations than the methods currently available in Autodock

COVID‐19, nationalism, and the politics of crisis: A scholarly exchange

In this article, several scholars of nationalism discuss the potential for the COVID‐19 pandemic to impact the development of nationalism and world politics. To structure the discussion, the contributors respond to three questions: (1) how should we understand the relationship between nationalism and COVID‐19; (2) will COVID‐19 fuel ethnic and nationalist conflict; and (3) will COVID‐19 reinforce or erode the nation‐state in the long run? The contributors formulated their responses to these questions near to the outset of the pandemic, amid intense uncertainty. This made it acutely difficult, if not impossible, to make predictions. Nevertheless, it was felt that a historically and theoretically informed discussion would shed light on the types of political processes that could be triggered by the COVID‐19 pandemic. In doing so, the aim is to help orient researchers and policy‐makers as they grapple with what has rapidly become the most urgent issue of our times

Evolving Synaptic Plasticity with an Evolutionary Cellular Development Model

Since synaptic plasticity is regarded as a potential mechanism for memory formation and learning, there is growing interest in the study of its underlying mechanisms. Recently several evolutionary models of cellular development have been presented, but none have been shown to be able to evolve a range of biological synaptic plasticity regimes. In this paper we present a biologically plausible evolutionary cellular development model and test its ability to evolve different biological synaptic plasticity regimes. The core of the model is a genomic and proteomic regulation network which controls cells and their neurites in a 2D environment. The model has previously been shown to successfully evolve behaving organisms, enable gene related phenomena, and produce biological neural mechanisms such as temporal representations. Several experiments are described in which the model evolves different synaptic plasticity regimes using a direct fitness function. Other experiments examine the ability of the model to evolve simple plasticity regimes in a task -based fitness function environment. These results suggest that such evolutionary cellular development models have the potential to be used as a research tool for investigating the evolutionary aspects of synaptic plasticity and at the same time can serve as the basis for novel artificial computational systems