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Full-Text Articles in Physical Sciences and Mathematics

Laser-Induced Photon-Branched Chain Reaction In A Chemically-Active Gas-Dispersed Medium, Thomas F. George, Renat R. Letfullin, Galen C. Duree Dec 2008

Laser-Induced Photon-Branched Chain Reaction In A Chemically-Active Gas-Dispersed Medium, Thomas F. George, Renat R. Letfullin, Galen C. Duree

Thomas George

A promising avenue in the development of high-energy pulsed chemical HF/DF lasers and amplifiers is the utilization of a photon-branched chain reaction initiated in a two-phase active medium, that is, a medium containing a laser working gas and ultradispersed passivated metal particles. These particles are evaporated under the action of IR laser radiation which results in the appearance of free atoms, their diffusion into the gas, and the development of a photon-branching chain process, which involves photons as both reactants and products. The key obstacle here is the formation of a relatively large volume (in excess of 10^3 cm^3) of the …


Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto Dec 2008

Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto

Douglas D. Piirto

Individual trees of giant sequoia (Sequoia gigantea [Lindl.] Decne.) have demonstrated a capacity to attain both a long life and very large size. It is not uncommon to find old-growth giant sequoia trees in their native range that are 1,500 years old and over 15 feet in diameter at breast height. The ability of individual giant sequoia trees to survive over such long periods of time has often been attributed to the species high resistance to disease, insect, and fire damage. Such a statement, however, is a gross oversimplification, given broader ecosystem and temporal interactions. For example, why isn't there …


Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson Dec 2008

Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson

Douglas D. Piirto

Three methods of tanoak (Lithocarpus densiflorus [Hook. & Arn.] Rehd.) control involving the application of the amine or ester form of triclopyr were evaluated in this coast redwood uneven-aged forest management study of herbicides. A cut-stump application with the amine form of triclopyr (Garlon 3A), frill cut with the amine form of triclopyr, basal-bark (outer surface) with the ester form of triclopyr (Garlon 4), and an untreated control were replicated three times. The tanoak control results in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and/ or coast redwood (Sequoia sempervirens [D. Don] Endl.) predominated stands obtained in earlier studies …


Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto Dec 2008

Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto

Douglas D. Piirto

Fire management has always meant fire suppression to the managers of the chaparral covered southern California National Forests. Today, Forest Service fire management programs must be cost effective, while wilderness fire management objectives are aimed at recreating natural fire regimes. A cost-effectiveness analysis has been developed to compare fire management options for meeting these objectives in California's chaparral wilderness. This paper describes the analytical procedure using examples from a study currently being conducted for the Los Padres National Forest, and discusses some preliminary results.


Word Sense Disambiguation In Biomedical Ontologies With Term Co-Occurrence Analysis And Document Clustering, Bill Andreopoulos, Dimitra Alexopoulou, Michael Schroeder Sep 2008

Word Sense Disambiguation In Biomedical Ontologies With Term Co-Occurrence Analysis And Document Clustering, Bill Andreopoulos, Dimitra Alexopoulou, Michael Schroeder

William B. Andreopoulos

With more and more genomes being sequenced, a lot of effort is devoted to their annotation with terms from controlled vocabularies such as the GeneOntology. Manual annotation based on relevant literature is tedious, but automation of this process is difficult. One particularly challenging problem is word sense disambiguation. Terms such as |development| can refer to developmental biology or to the more general sense. Here, we present two approaches to address this problem by using term co-occurrences and document clustering. To evaluate our method we defined a corpus of 331 documents on development and developmental biology. Term co-occurrence analysis achieves an …


Simultaneous Confidence Bands For The Coefficient Function In Functional Regression, Philip T. Reiss Aug 2008

Simultaneous Confidence Bands For The Coefficient Function In Functional Regression, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Inferring Group Differences In Brain Connectivity From Functional Magnetic Resonance Images, Philip T. Reiss Jul 2008

Inferring Group Differences In Brain Connectivity From Functional Magnetic Resonance Images, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Unraveling Protein Networks With Power Graph Analysis, Loïc Royer, Matthias Reimann, Bill Andreopoulos, Michael Schroeder Jul 2008

Unraveling Protein Networks With Power Graph Analysis, Loïc Royer, Matthias Reimann, Bill Andreopoulos, Michael Schroeder

William B. Andreopoulos

Networks play a crucial role in computational biology, yet their analysis and representation is still an open problem. Power Graph Analysis is a lossless transformation of biological networks into a compact, less redundant representation, exploiting the abundance of cliques and bicliques as elementary topological motifs. We demonstrate with five examples the advantages of Power Graph Analysis. Investigating protein-protein interaction networks, we show how the catalytic subunits of the casein kinase II complex are distinguishable from the regulatory subunits, how interaction profiles and sequence phylogeny of SH3 domains correlate, and how false positive interactions among high-throughput interactions are spotted. Additionally, we …


Reliability Of Functional Connectivity Networks: How Can We Assess It?, Philip T. Reiss Jul 2008

Reliability Of Functional Connectivity Networks: How Can We Assess It?, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Polypyrrole Based Switchable Filter System, Yanzhe Wu, Lorrain Nolan, Shirley Coyle, King Tong Lau, Gordon G. Wallace, Dermot Diamond Jun 2008

Polypyrrole Based Switchable Filter System, Yanzhe Wu, Lorrain Nolan, Shirley Coyle, King Tong Lau, Gordon G. Wallace, Dermot Diamond

Gordon Wallace

BioTex is an EU funded project aiming to develop textile-based sensors for monitoring biological fluids. In the context of the project, there is a need to develop an effective sample delivery strategy for the wearable biomedical devices. A compact, electroactive switchable membrane would be useful as a valve to control the sample delivery within such devices. A method that employed inherently conducting polymers deposited onto a permeable substrate to form a switchable membrane was investigated [1, 2, 3]. By application of specific voltages, the permeability (pore size) of the membrane can be switched to swollen (expand) and contracted forms, which …


Conducting Polymer-Carbon Nanotubes Composites, May Tahhan, N. Barisci, Gordon G. Wallace May 2008

Conducting Polymer-Carbon Nanotubes Composites, May Tahhan, N. Barisci, Gordon G. Wallace

Gordon Wallace

During the course of this work, three different approaches to the formation of conducting polymer/carbon nanotube (CP/CNT) composites were investigated. The first approach involved the preparation of CNT dispersions using Poly methoxy aniline-5-sulfonic acid (PMAS) as a stabilizer. The second approach investigated involved the use of CNT as the dopant in the electropolymerization of CPs. The third approach involved the electrochemical deposition of a thin polymer film onto the surface of CNT paper. These CNT/CP composites were characterized to determine capacitance, conductivity and mechanical strength.


Writing Research Proposal: Literature Review And Database Search, Mamoudou H. Dicko Prof. May 2008

Writing Research Proposal: Literature Review And Database Search, Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The maiden proposed research project should demonstrate that the present study will add a significant knowledge on the subject. The main objective of the literature research is to allow that the statement of the research need will clearly establish the objective of the new study.


Dioxidobis(2-Oxo-1,2-Dihydropyridin-3-Olato)­Molybdenum(Vi), Manoj Trivedi, Daya Shankar Pandey, Nigam P. Rath Apr 2008

Dioxidobis(2-Oxo-1,2-Dihydropyridin-3-Olato)­Molybdenum(Vi), Manoj Trivedi, Daya Shankar Pandey, Nigam P. Rath

Nigam Rath

In the title compound, [Mo(C5H4NO2)2O2], the MoVI atom exhibits a distorted octa­hedral coordination geometry formed by two terminal oxo ligands and two monoanionic O,O-bidentate pyridinone ligands. The two terminal oxo ligands lie in a cis arrangement, the ketonic O atoms of the pyridinone ligands are coordinated trans to the oxo ligands and the deprotonated hydroxyl O atoms are located trans to each other. The crystal structure contains inter­molecular N-H...O hydrogen bonds, C-H...O contacts and face-to-face [pi]-[pi] stacking inter­actions with an inter­planar separation of 3.25 (1) Å.


Diethyl 2-[(4-Nitro­Phen­Yl)(4-Phenyl-1,2,3-Selenadiazol-5-Yl)Meth­Yl]Malonate, A. Marx, S. Saravanan, S. Muthusubramanian, V. Manivannan, Nigam P. Rath Apr 2008

Diethyl 2-[(4-Nitro­Phen­Yl)(4-Phenyl-1,2,3-Selenadiazol-5-Yl)Meth­Yl]Malonate, A. Marx, S. Saravanan, S. Muthusubramanian, V. Manivannan, Nigam P. Rath

Nigam Rath

In the title compound, C22H21N3O6Se, the heterocyclic ring makes dihedral angles of 50.03 (11) and 67.75 (11)°, respectively, with the benzene and phenyl rings. The terminal C atoms of the ester groups are disordered over two positions: the site occupancies for the C atoms are 0.62 (3)/0.38 (3) and 0.48 (3)/0.52 (3). In the crystal structure, weak intra- and inter­molecular C-H...O inter­actions are observed.


Second-Sphere Amino Acids Contribute To Transition-State Structure In Bovine Purine Nucleoside Phosphorylase, Lei Li, Minkui Luo, Mahmoud Ghanem, Erika A. Taylor, Vern L. Schramm Feb 2008

Second-Sphere Amino Acids Contribute To Transition-State Structure In Bovine Purine Nucleoside Phosphorylase, Lei Li, Minkui Luo, Mahmoud Ghanem, Erika A. Taylor, Vern L. Schramm

Erika A. Taylor, Ph.D.

Transition-state structures of human and bovine of purine nucleoside phosphorylases differ, despite 87% homologous amino acid sequences. Human PNP (HsPNP) has a fully dissociated transition state, while that for bovine PNP (BtPNP) has early SN1 character. Crystal structures and sequence alignment indicate that the active sites of these enzymes are the same within crystallographic analysis, but residues in the second-sphere from the active sites differ significantly. Residues in BtPNP have been mutated toward HsPNP, resulting in double (Asn123Lys; Arg210Gln) and triple mutant PNPs (Val39Thr; Asn123Lys; Arg210Gln). Steady-state kinetic studies indicated unchanged catalytic activity, while pre-steady-state studies indicate that the chemical …


4-(4-Chlorophenyl)-5-[1-(4-Chlorophenyl)-2-Methyl-2-Nitropropyl]-1,2,3-Selenadiazole, A. Marx, S. Saravanan, S. Muthusubramanian, V. Manivannan, Nigam P. Rath Feb 2008

4-(4-Chlorophenyl)-5-[1-(4-Chlorophenyl)-2-Methyl-2-Nitropropyl]-1,2,3-Selenadiazole, A. Marx, S. Saravanan, S. Muthusubramanian, V. Manivannan, Nigam P. Rath

Nigam Rath

In the title compound, C18H15Cl2N3O2Se, the selenadiazole ring makes dihedral angles of 49.87 (3) and 55.70 (3)° with the two benzene rings. The dihedral angle between the two benzene rings is 11.90 (5)°. In the crystal structure, intra­molecular C-H...O and C-H...Se inter­actions and inter­molecular C-H...O, C-H...Cl and C-H...N inter­actions are observed.


Brain Bases Of Individual Differences In Cognition, Chantel Prat, Marcel Just Dec 2007

Brain Bases Of Individual Differences In Cognition, Chantel Prat, Marcel Just

Marcel Adam Just

No abstract provided.


A Decrease In Brain Activation Associated With Driving When Listening To Someone Speak, Marcel Just, Timothy Keller, Jacquelyn Cynkar Dec 2007

A Decrease In Brain Activation Associated With Driving When Listening To Someone Speak, Marcel Just, Timothy Keller, Jacquelyn Cynkar

Marcel Adam Just

No abstract provided.


Fmri Investigation Of Working Memory For Faces In Autism: Visual Coding And Underconnectivity With Frontal Areas, Hideya Koshino, Rajesh Kana, Timothy Keller, Vladimir Cherkassky, Nancy Minshew, Marcel Just Dec 2007

Fmri Investigation Of Working Memory For Faces In Autism: Visual Coding And Underconnectivity With Frontal Areas, Hideya Koshino, Rajesh Kana, Timothy Keller, Vladimir Cherkassky, Nancy Minshew, Marcel Just

Marcel Adam Just

No abstract provided.


Using Fmri Brain Activation To Identify Cognitive States Associated With Perception Of Tools And Dwellings, Svetlana V. Shinkareva, Robert A. Mason, Vicente L. Malave, Wei Wang, Tom M. Mitchell, Marcel Adam Just Dec 2007

Using Fmri Brain Activation To Identify Cognitive States Associated With Perception Of Tools And Dwellings, Svetlana V. Shinkareva, Robert A. Mason, Vicente L. Malave, Wei Wang, Tom M. Mitchell, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Modifying The Brain Activation Of Poor Readers During Sentence Comprehension With Extended Remedial Instruction: A Longitudinal Study Of Neuroplasticity, Ann Meyler, Timothy A. Keller, Vladimir L. Cherkassky, John D. E. Gabrieli, Marcel Adam Just Dec 2007

Modifying The Brain Activation Of Poor Readers During Sentence Comprehension With Extended Remedial Instruction: A Longitudinal Study Of Neuroplasticity, Ann Meyler, Timothy A. Keller, Vladimir L. Cherkassky, John D. E. Gabrieli, Marcel Adam Just

Marcel Adam Just

No abstract provided.


What Brain Imaging Can Tell Us About Embodied Meaning, Marcel Adam Just Dec 2007

What Brain Imaging Can Tell Us About Embodied Meaning, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Theory Of Mind Disruption And Recruitment Of The Right Hemisphere During Narrative Comprehension In Autism, Robert A. Mason, Diane L. Williams, Rajesh K. Kana, Nancy J. Minshew, Marcel Adam Just Dec 2007

Theory Of Mind Disruption And Recruitment Of The Right Hemisphere During Narrative Comprehension In Autism, Robert A. Mason, Diane L. Williams, Rajesh K. Kana, Nancy J. Minshew, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Hierarchies Of Networked Phases Induced By Multiple Liquid-Liquid Critical Points, C. W. Hsu, J. Largo, F. W. Sciortino, Francis Starr Dec 2007

Hierarchies Of Networked Phases Induced By Multiple Liquid-Liquid Critical Points, C. W. Hsu, J. Largo, F. W. Sciortino, Francis Starr

Francis Starr

No abstract provided.


Bush Lemons And Beach Hauling: Evolving Traditions And New Thinking For Protected Areas Management And Aboriginal People In New South Wales, Michael Adams, Vanessa Cavanagh, Bridget Edmunds Dec 2007

Bush Lemons And Beach Hauling: Evolving Traditions And New Thinking For Protected Areas Management And Aboriginal People In New South Wales, Michael Adams, Vanessa Cavanagh, Bridget Edmunds

Vanessa Cavanagh

Aboriginal communities in New South Wales currently are engaged in negotiating with government agencies
about cultural activities focussing on access to and harvest of wild resources on and off protected areas. These
are ‘co-management’ situations in the broadest sense, where both Indigenous peoples and protected area
management agencies actively are engaged in the same landscape. Aboriginal peoples are using adaptive
approaches to continue millennia of cultural traditions in social and physical environments that are
significantly changed and changing. Some protected area managers are seeking to understand and adapt
agency responses, so as to engage and support Aboriginal interests. These contrasting …


Predicting Human Brain Activity Associated With The Meanings Of Nouns, Tom M. Mitchell, Svetlana V. Shinkareva, Andrew Carlson, Kai-Min Chang, Vicente L. Malave, Robert A. Mason, Marcel Adam Just Dec 2007

Predicting Human Brain Activity Associated With The Meanings Of Nouns, Tom M. Mitchell, Svetlana V. Shinkareva, Andrew Carlson, Kai-Min Chang, Vicente L. Malave, Robert A. Mason, Marcel Adam Just

Marcel Adam Just

No abstract provided.


The Dynamic Evolutionary History Of The Bananaquit (Coereba Flaveola) In The Caribbean Revealed By A Multigene Analysis, Eva Bellemain, Eldredge Bermingham, Robert E. Ricklefs Dec 2007

The Dynamic Evolutionary History Of The Bananaquit (Coereba Flaveola) In The Caribbean Revealed By A Multigene Analysis, Eva Bellemain, Eldredge Bermingham, Robert E. Ricklefs

Robert Ricklefs

Background
The bananaquit (Coereba flaveola) is a small nectivorous and frugivorous emberizine bird (order Passeriformes) that is an abundant resident throughout the Caribbean region. We used multi-gene analyses to investigate the evolutionary history of this species throughout its distribution in the West Indies and in South and Middle America. We sequenced six mitochondrial genes (3744 base pairs) and three nuclear genes (2049 base pairs) for forty-four bananaquits and three outgroup species. We infer the ancestral area of the present-day bananaquit populations, report on the species' phylogenetic, biogeographic and evolutionary history, and propose scenarios for its diversification and range …


The Plant Ontology Database: A Community Resource For Plant Structure And Developmental Stages Controlled Vocabulary And Annotations, Shulamit Avraham, Chih-Wei Tung, Katica Ilic, Pankaj Jaiswal, Elizabeth A. Kellogg, Susan Mccouch, Anuradha Pujar, Leonore Reiser, Seung Yon Rhee, Martin M. Sachs, Mary L. Schaeffer, Lincoln Stein, Peter Stevens, Leszek Vincent, Felipe Zapata, Doreen Ware Dec 2007

The Plant Ontology Database: A Community Resource For Plant Structure And Developmental Stages Controlled Vocabulary And Annotations, Shulamit Avraham, Chih-Wei Tung, Katica Ilic, Pankaj Jaiswal, Elizabeth A. Kellogg, Susan Mccouch, Anuradha Pujar, Leonore Reiser, Seung Yon Rhee, Martin M. Sachs, Mary L. Schaeffer, Lincoln Stein, Peter Stevens, Leszek Vincent, Felipe Zapata, Doreen Ware

Peter Stevens

The Plant Ontology Consortium (POC, http://www.plantontology.org ) is a collaborative effort among model plant genome databases and plant researchers that aims to create, maintain and facilitate the use of a controlled vocabulary (ontology) for plants. The ontology allows users to ascribe attributes of plant structure (anatomy and morphology) and developmental stages to data types, such as genes and phenotypes, to provide a semantic framework to make meaningful cross-species and database comparisons. The POC builds upon groundbreaking work by the Gene Ontology Consortium (GOC) by adopting and extending the GOC's principles, existing software and database structure. Over the past year, POC …


Functional Generalized Linear Models With Applications To Neuroimaging, Philip T. Reiss, R. Todd Ogden Dec 2007

Functional Generalized Linear Models With Applications To Neuroimaging, Philip T. Reiss, R. Todd Ogden

Philip T. Reiss

No abstract provided.


Tetra-N-Butyl­Ammonium Bis­(2,2-Dicyano­Ethyl­Ene-1,1-Dithiol­Ato)Palladium(Ii), Nyasha Kanganga, Kent R. Mann, Daron E. Janzen Dec 2007

Tetra-N-Butyl­Ammonium Bis­(2,2-Dicyano­Ethyl­Ene-1,1-Dithiol­Ato)Palladium(Ii), Nyasha Kanganga, Kent R. Mann, Daron E. Janzen

Daron E Janzen, Ph.D.

No abstract provided.