96 research outputs found
Input-Output Tables for Alaska's Economy: A First Look
The specific objectives of this publication are to: ( 1) present a first
look in specific detail at the input-output tables of the Alaskan
economy, thereby examining Alaskan interindustry interactions and
dependencies; and (2) indicate, via relevant examples, how the information
contained in these typical input-out tables can be used by
private and public policymakers.Geographic isolation, a subarctic climate, large size, and a regionally
diverse landscape make Alaska a unique part of the United States. The
factors that make Alaska so unique also contribute to her present lack
of industrial and agricultural production, which requires shipment into
the state of most of the goods necessary for life. In filling the need for
such goods, the state of Washington has been, and continues to be, the
principal marketing and transportation center for Alaska-associated
trade
Complete Specification of DDM Mechanisms
The specification of DDM (Distributed Decision-Making) algorithms is addressed. The modeling technique presented is based on well-known extensions to Petri-Nets (PNs). Transition-enabling functions with a domain corresponding to the marking of a net are used to express the semantics of decision-making. Furthermore, the algorithm structural characteristics of global state representation and topology are incorporated. Finally, the dynamic nature of evolution of system state, interaction with processes external to the computation, and the interprocess communication aspects of the mechanism are also modeled. The elements of analysis associated with this model are described, but not detailed in the scope of this paper
Prospectus for a Remote PASM Execution and Debugging Environment - PDB
This document describes four design alternatives for a remote debugging and execution environment for the PASM Parallel Processing System Prototype in the School of EE at Purdue. Two alternatives involve acquisition of modest hardware for system enhancement, while the others are software-only solutions. All solutions involve use of a high-resolution bit-mapped graphics device, mouse and keyboard input, and a broad-band Ethernet-like communication medium. These latter components are currently available. The goal of this environment is to support any type of debugging which is currently supported by using the front panel of the machine and several terminals which are manually multiplexed between PEs and other resource management processors of the system. The environment will support voluntary output of processor activity from, and input to, any of the 30 processors of the PASM prototype. This configuration represents a step toward multiprogramming of the machine and will support development of software tools, languages and additional applications. Debugging information will be in the form of textual (or other) output displayed on virtual windows of a high-resolution device such as a SUN 3/50
Experimental Evaluation of SIMD PE-Mask Generation and Hybrid Mode Parallel Computing on Multi- Microprocessor Systems
Experimentation aimed at determining the potential efficiency of multi-microprocessor designs of SIMD machines is reported. The experimentation is based on timing measurements made on the PASM system prototype at Purdue. The application used to measure and evaluate this phenomenon was bitonic sorting, which has feasible solutions in both SIMD and MIMD modes of computation, as well as in at least two hybrids of SlMD and MIMD modes. Bitonic sorting was coded in these four ways and experiments were performed that examine the tradeoffs among all of these modes. Also, a new PE mask generation scheme for multiple of-the-shelf microprocessor based SIMD systems is proposed, and its performance was measured
Insights into a dinoflagellate genome through expressed sequence tag analysis
BACKGROUND: Dinoflagellates are important marine primary producers and grazers and cause toxic "red tides". These taxa are characterized by many unique features such as immense genomes, the absence of nucleosomes, and photosynthetic organelles (plastids) that have been gained and lost multiple times. We generated EST sequences from non-normalized and normalized cDNA libraries from a culture of the toxic species Alexandrium tamarense to elucidate dinoflagellate evolution. Previous analyses of these data have clarified plastid origin and here we study the gene content, annotate the ESTs, and analyze the genes that are putatively involved in DNA packaging. RESULTS: Approximately 20% of the 6,723 unique (11,171 total 3'-reads) ESTs data could be annotated using Blast searches against GenBank. Several putative dinoflagellate-specific mRNAs were identified, including one novel plastid protein. Dinoflagellate genes, similar to other eukaryotes, have a high GC-content that is reflected in the amino acid codon usage. Highly represented transcripts include histone-like (HLP) and luciferin binding proteins and several genes occur in families that encode nearly identical proteins. We also identified rare transcripts encoding a predicted protein highly similar to histone H2A.X. We speculate this histone may be retained for its role in DNA double-strand break repair. CONCLUSION: This is the most extensive collection to date of ESTs from a toxic dinoflagellate. These data will be instrumental to future research to understand the unique and complex cell biology of these organisms and for potentially identifying the genes involved in toxin production
An annotated cDNA library of juvenile Euprymna scolopes with and without colonization by the symbiont Vibrio fischeri
BACKGROUND: Biologists are becoming increasingly aware that the interaction of animals, including humans, with their coevolved bacterial partners is essential for health. This growing awareness has been a driving force for the development of models for the study of beneficial animal-bacterial interactions. In the squid-vibrio model, symbiotic Vibrio fischeri induce dramatic developmental changes in the light organ of host Euprymna scolopes over the first hours to days of their partnership. We report here the creation of a juvenile light-organ specific EST database. RESULTS: We generated eleven cDNA libraries from the light organ of E. scolopes at developmentally significant time points with and without colonization by V. fischeri. Single pass 3' sequencing efforts generated 42,564 expressed sequence tags (ESTs) of which 35,421 passed our quality criteria and were then clustered via the UIcluster program into 13,962 nonredundant sequences. The cDNA clones representing these nonredundant sequences were sequenced from the 5' end of the vector and 58% of these resulting sequences overlapped significantly with the associated 3' sequence to generate 8,067 contigs with an average sequence length of 1,065 bp. All sequences were annotated with BLASTX (E-value < -03) and Gene Ontology (GO). CONCLUSION: Both the number of ESTs generated from each library and GO categorizations are reflective of the activity state of the light organ during these early stages of symbiosis. Future analyses of the sequences identified in these libraries promise to provide valuable information not only about pathways involved in colonization and early development of the squid light organ, but also about pathways conserved in response to bacterial colonization across the animal kingdom
High-throughput gene discovery in the rat
The rat is an important animal model for human diseases and is widely used in physiology. In this article we present a new strategy for gene discovery based on the production of ESTs from serially subtracted and normalized cDNA libraries, and we describe its application for the development of a comprehensive nonredundant collection of rat ESTs. Our new strategy appears to yield substantially more EST clusters per ESTs sequenced than do previous approaches that did not use serial subtraction. However, multiple rounds of library subtraction resulted in high frequencies of otherwise rare internally primed cDNAs, defining the limits of this powerful approach. To date, we have generated >200,000 3′ ESTs from >100 cDNA libraries representing a wide range of tissues and developmental stages of the laboratory rat. Most importantly, we have contributed to ∼50,000 rat UniGene clusters. We have identified, arrayed, and derived 5′ ESTs from >30,000 unique rat cDNA clones. Complete information, including radiation hybrid mapping data, is also maintained locally at http://genome.uiowa.edu/clcg.html. All of the sequences described in this article have been submitted to the dbEST division of the NCBI
Putative Multifunctional Signature of Lung Metastases in Dedifferentiated Chondrosarcoma
Inhibition of Electrical Activity by Retroviral Infection with Kir2.1 Transgenes Disrupts Electrical Differentiation of Motoneurons
Network-driven spontaneous electrical activity in the chicken spinal cord regulates a variety of developmental processes including neuronal differentiation and formation of neuromuscular structures. In this study we have examined the effect of chronic inhibition of spinal cord activity on motoneuron survival and differentiation. Early spinal cord activity in chick embryos was blocked using an avian replication-competent retroviral vector RCASBP (B) carrying the inward rectifier potassium channel Kir2.1. Chicken embryos were infected with one of the following constructs: RCASBP(B), RCASBP(B)-Kir2.1, or RCASBP(B)-GFP. Infection of chicken embryos at E2 resulted in widespread expression of the viral protein marker p27 gag throughout the spinal cord. Electrophysiological recordings revealed the presence of functional Kir2.1 channels in RCASBP(B)-Kir2.1 but not in RCASBP(B)-infected embryos. Kir2.1 expression significantly reduced the generation of spontaneous motor movements in chicken embryos developing in ovo. Suppression of spontaneous electrical activity was not due to a reduction in the number of surviving motoneurons or the number of synapses in hindlimb muscle tissue. Disruption of the normal pattern of activity in chicken embryos resulted in a significant downregulation in the functional expression of large-conductance Ca2+-dependent K+ channels. Reduction of spinal cord activity also generates a significant acceleration in the inactivation rate of A-type K+ currents without any significant change in current density. Kir2.1 expression did not affect the expression of voltage-gated Na+ channels or cell capacitance. These experiments demonstrate that chronic inhibition of chicken spinal cord activity causes a significant change in the electrical properties of developing motoneurons
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