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Full-Text Articles in Physical Sciences and Mathematics

Statistical Issues In Proteomic Research, Jeffrey S. Morris Dec 2007

Statistical Issues In Proteomic Research, Jeffrey S. Morris

Jeffrey S. Morris

No abstract provided.


Spatial And Temporal Patterns Of Nitrogen Deposition In China: Synthesis Of Observational Data, Chaoqun (Crystal) Lu, Hanqin Tian Nov 2007

Spatial And Temporal Patterns Of Nitrogen Deposition In China: Synthesis Of Observational Data, Chaoqun (Crystal) Lu, Hanqin Tian

Chaoqun (Crystal) Lu

Anthropogenic nitrous pollutant emissions in China significantly increased during the last decades, which contributed to the accelerated nitrogen (N) deposition. In order to characterize spatial pattern of nitrogen deposition, we employed the kriging technique to interpolate sampling data of precipitation chemistry and ambient air concentration from site-network observations over China. The estimation of wet deposition in China was limited to aqueous NO3− and NH4+, while ambient NO2 was the only species involved in the predicted dry deposition fluxes. To obtain wet deposition fluxes, precipitation concentration was multiplied by 20-year mean precipitation amounts with a resolution of 10 × 10 km. …


Biogeographical Distribution And Natural Groupings Among Five Sympatric Wild Cats In Tropical South Asia, Mohammed Ashraf Oct 2007

Biogeographical Distribution And Natural Groupings Among Five Sympatric Wild Cats In Tropical South Asia, Mohammed Ashraf

Mohammed Ashraf

Small to large carnivorous mammals in the tropical belt face extinction at an unprecedented rate. The vanishing of sympatric wild cats appears to be due to habitat fragmentation, human encroachment & poaching. The focus of this study is on ecological and distributional parameters that influence the wild cat communities in tropical South Asia. The distributional data for five sympatric cats is analyzed with the aim of understanding the species-habitat association under a conceptually unified binary-matrix framework. The use of cluster analysis techniques in this ecological study have helped to reveal the natural groupings among felid guilds and their ecological resource …


Meta-Analysis Evidence Of A Differential Risk Of The Fcrl3 -169t->C Polymorphism In White And East Asian Rheumatoid Arthritis Patients, Steven J. Schrodi, Begovich Ann, Chang Monica Jul 2007

Meta-Analysis Evidence Of A Differential Risk Of The Fcrl3 -169t->C Polymorphism In White And East Asian Rheumatoid Arthritis Patients, Steven J. Schrodi, Begovich Ann, Chang Monica

Steven J Schrodi

Association between a functional promoter polymorphism (rs7528684) in the Fc receptor-like gene, FCRL3, and rheumatoid arthritis (RA) has been observed in 3 independent Japanese case-control sample sets ([1][2]). Studies examining the role of this polymorphism in risk of RA in 9 independent white sample sets, however, have yielded conflicting results ([3-8]). Further, a large study of Korean subjects failed to demonstrate association of this single-nucleotide polymorphism (SNP) with RA ([9]). Although the precise function of FCRL3, which has strong structural homology with the classic Fc receptors, is unknown, the existing data are consistent with the hypothesis that it may influence …


Quantifying Total And Sustainable Agricultural Biomass Resources In South Dakota, Kurt A. Rosentrater, Russell Persyn, Dennis Todey Jun 2007

Quantifying Total And Sustainable Agricultural Biomass Resources In South Dakota, Kurt A. Rosentrater, Russell Persyn, Dennis Todey

Kurt A. Rosentrater

Conversion of biomass is considered the next major advance in biorenewable fuels, energy, and products. Wholesale conversion to biomass utilization could result in removal of current crop residues from agricultural fields or even implementation of different crops and cropping strategies (i.e., switchgrass). To date, the driver for biomass processing has been economics and limitations on the conversion of the lignocellulose. Over the last forty years significant investments and resultant changes in management practices in the agricultural sector have focused on soil and water conservation. One of the major efforts has focused on conservation-till or no-till, with the goal of retaining …


A Large-Scale Rheumatoid Arthritis Genetic Study Identifies Association At Chr 9q33.2, Steven J. Schrodi May 2007

A Large-Scale Rheumatoid Arthritis Genetic Study Identifies Association At Chr 9q33.2, Steven J. Schrodi

Steven J Schrodi

No abstract provided.


Depleted Carbon Monoxide In Fragment C Of The Jupiter-Family Comet 73p/Schwassmann-Wachmann 3, M. A. Disanti, W. M. Anderson, G. L. Villanueva, B. P. Bonev, K. Magee-Sauer, E. L. Gibb, M. J. Mumma May 2007

Depleted Carbon Monoxide In Fragment C Of The Jupiter-Family Comet 73p/Schwassmann-Wachmann 3, M. A. Disanti, W. M. Anderson, G. L. Villanueva, B. P. Bonev, K. Magee-Sauer, E. L. Gibb, M. J. Mumma

Erika Gibb

Carbon monoxide emission was targeted in fragment C of the recently split Jupiter-family comet 73P/Schwassmann-Wachmann 3 during its 2006 apparition, using the Cryogenic Echelle Spectrograph (CSHELL) at the NASA IRTF on Mauna Kea, Hawaii. Simultaneous sounding with H2O near 4.65 μm revealed highly depleted CO, consistent with a mixing ratio of 0.5% ± 0.13%. Along with depleted CH3OH but nearly normal HCN, this may indicate that this comet formed in the inner giant planets' region or, alternatively, that it formed relatively late, after significant clearing of the protosolar nebula.


Compression Molding Of Phenolic Resin And Corn-Based Ddgs Blends, Kurt A. Rosentrater, R. A. Tatara, S. Suraparaju Apr 2007

Compression Molding Of Phenolic Resin And Corn-Based Ddgs Blends, Kurt A. Rosentrater, R. A. Tatara, S. Suraparaju

Kurt A. Rosentrater

With the rapid growth in the ethanol fuel industry in recent years, considerable research is being devoted to optimizing the use of processing coproducts, such as distillers dried grains with solubles (DDGS), in livestock diets. Because these residues contain high fiber levels, they may be amendable to incorporation into bio-based composites. Thus, the goal of this study was to demonstrate the viability of using corn-based DDGS as a biofiller with phenolic resin, in order to produce a novel biomaterial. DDGS was blended with phenolic resin at 0, 10, 25, 50, 75, and 90%, by weight, and then compression molded at …


High-Loading Nanosized Micelles Of Copoly(Styrene-Maleic Acid)-Zinc Protoporphyrin For Targeted Delivery Of A Potent Heme Oxygenase Inhibitor., Arun Iyer Mar 2007

High-Loading Nanosized Micelles Of Copoly(Styrene-Maleic Acid)-Zinc Protoporphyrin For Targeted Delivery Of A Potent Heme Oxygenase Inhibitor., Arun Iyer

Arun Iyer

Amphiphilic styrene-maleic acid (SMA) copolymer efficiently formed micelles with a potent heme oxygenase inhibitor-zinc protoporphyrin (ZnPP). The micelles were constructed by subtle pH adjustments to form non-covalent interaction between the hydrophobic ZnPP and amphiphilic SMA. The micelles (SMA-ZnPP) thus formed were nanoparticles with narrow size distribution in water (mean diameter 176.5nm), having tunable loading (from 15% to 60% w/w of ZnPP) with remarkable aqueous solubility. SMA-ZnPP had an average molecular size of 144kDa as determined by size-exclusion chromatography (SEC), this size is a marked increase from the molecular weight of free ZnPP (626.03Da), suggesting the formation of micellar structure. The …


Using Math In Cell Biology: A Tale Of Two Channel Types, Borbala Mazzag Mar 2007

Using Math In Cell Biology: A Tale Of Two Channel Types, Borbala Mazzag

Borbala Mazzag

No abstract provided.


Land Cover Classification And Economic Assessment Of Citrus Groves Using Remote Sensing, Jennifer Gebelein Jan 2007

Land Cover Classification And Economic Assessment Of Citrus Groves Using Remote Sensing, Jennifer Gebelein

Jennifer Gebelein

The citrus industry has the second largest impact on Florida's economy, following tourism. Estimation of citrus area coverage and annual forecasts of Florida's citrus production are currently dependent on labor-intensive interpretation of aerial photographs. Remotely sensed data from satellites has been widely applied in agricultural yield estimation and cropland management. Satellite data can potentially be obtained throughout the year, making it especially suitable for the detection of land cover change in agriculture and ...


Contamination Levels Of Selected Organochlorine And Organophosphate Pesticides In The Selangor River, Malaysia Between 2002 To 2003, Kok Hoong Leong Jan 2007

Contamination Levels Of Selected Organochlorine And Organophosphate Pesticides In The Selangor River, Malaysia Between 2002 To 2003, Kok Hoong Leong

Kok Hoong Leong

In Malaysia, rivers are the main source of public water supplies. This study was conducted from 2002 to 2003 to determine the levels of selected organochlorine and organophosphate pesticides in the Selangor River in Malaysia. Surface water samples have been collected seasonally from nine sites along the river. A liquid–liquid extraction followed by gas chromatography–mass spectrometry technique was used to determine the trace levels of these pesticide residues. The organochlorine pesticides detected were lindane, heptachlor, endosulfan, dieldrin, endosulfan sulfate, o,p′-DDT, p,p′-DDT, o,p′-DDE and p,p′-DDE whereas for organophosphate pesticides, they were chlorpyrifos and diazinon. At the river upstream where a dam …


Why Manage Terminology? Ten Quick Answers, Uwe Muegge Jan 2007

Why Manage Terminology? Ten Quick Answers, Uwe Muegge

Uwe Muegge

Terminology management is a hot topic these days. At the tcworld conference 2006, terminology had its own forum with hundreds of participants. And a number of highly visible institutions like the LISA Terminology Special Interest Group (SIG) has been evangelizing the development and use of standardized terminology in the business world for many years.


Disciplining Words: What You Always Wanted To Know About Terminology Management, Uwe Muegge Jan 2007

Disciplining Words: What You Always Wanted To Know About Terminology Management, Uwe Muegge

Uwe Muegge

Terminology management enables organizations of any size to use the same terms consistently within and across the communication types that accompany a product or service. Typical communication types include specifications, drawings, GUI, software strings, help systems, technical documentation, marketing materials, regulatory submissions, etc. As multiple authors typically contribute to these communications, terminology management is the most efficient solution for ensuring that the organization speaks with one voice.


Pre-Processing Mass Spectrometry Data, Kevin R. Coombes, Keith A. Baggerly, Jeffrey S. Morris Jan 2007

Pre-Processing Mass Spectrometry Data, Kevin R. Coombes, Keith A. Baggerly, Jeffrey S. Morris

Jeffrey S. Morris

No abstract provided.


Laser Capture Sampling And Analytical Issues In Proteomics, Howard Gutstein, Jeffrey S. Morris Jan 2007

Laser Capture Sampling And Analytical Issues In Proteomics, Howard Gutstein, Jeffrey S. Morris

Jeffrey S. Morris

Proteomics holds the promise of evaluating global changes in protein expression and post-translational modificaiton in response to environmental stimuli. However, difficulties in achieving cellular anatomic resolution and extracting specific types of proteins from cells have limited the efficacy of these techniques. Laser capture microdissection has provided a solution to the problem of anatomical resolution in tissues. New extraction methodologies have expanded the range of proteins identified in subsequent analyses. This review will examine the application of laser capture microdissection to proteomic tissue sampling, and subsequent extraction of these samples for differential expression analysis. Statistical and other quantitative issues important for …


Farming Systems Research On Crop Diversification, Tillage, And Management Effects On Yield, Pests, And Environmental Quality In A Semi-Arid Environment, Andrew W. Lenssen, U. Sainju, T. Caesar-Tonthat, B. Allen, R. Lartey Jan 2007

Farming Systems Research On Crop Diversification, Tillage, And Management Effects On Yield, Pests, And Environmental Quality In A Semi-Arid Environment, Andrew W. Lenssen, U. Sainju, T. Caesar-Tonthat, B. Allen, R. Lartey

Andrew W. Lenssen

Available water, depleted soil quality, and weed competition are important constraints to crop production in the northern Great Plains. The traditional rotation in the region has been spring wheat with summer fallow, which is used to accrue additional soil moisture for the subsequent wheat crop. Tillage during fallow periods controls weeds, which otherwise would use substantial amounts of water and inorganic nitrogen, decreasing the efficiency of fallow and increasing soil erosion. Chemical fallow and zero tillage systems improve soil water status for subsequent crops (Lenssen et al., 2007a), allowing for increased cropping intensity and improved nutrient cycling (Lenssen et al., …


Microbial Development In Distillers Wet Grains Produced During Fuel Ethanol Production From Corn (Zea Mays), R. Michael Lehman, Kurt A. Rosentrater Jan 2007

Microbial Development In Distillers Wet Grains Produced During Fuel Ethanol Production From Corn (Zea Mays), R. Michael Lehman, Kurt A. Rosentrater

Kurt A. Rosentrater

Distillers grains are coproduced with ethanol and carbon dioxide during the production of fuel ethanol from the dry milling and fermentation of corn grain, yet there is little basic microbiological information on these materials. We undertook a replicated field study of the microbiology of distillers wet grains (DWG) over a 9 day period following their production at an industrial fuel ethanol plant. Freshly produced DWG had a pH of about 4.4, a moisture content of about 53.5% (wet mass basis), and 4 x 10(5) total yeast cells/g dry mass, of which about 0.1% were viable. Total bacterial cells were initially …


Spatial Symmetry Groups As Sensorimotor Guidelines, Gin Mccollum Jan 2007

Spatial Symmetry Groups As Sensorimotor Guidelines, Gin Mccollum

Gin McCollum

While some aspects of neuroanatomical organization are related to packing and access rather than to function, other aspects of anatomical/physiological organization are directly related to function. The mathematics of symmetry groups can be used to determine logical structure in projections and to relate it to function. This paper reviews two studies of the symmetry groups of vestibular projections that are related to the spatial functions of the vestibular complex, including gaze, posture, and movement. These logical structures have been determined by finding symmetry groups of two vestibular projections directly from physiological and anatomical data. Logical structures in vestibular projections are …


Discontinuities In Stream Nutrient Uptake Below Lakesin Mountain Drainage Networks, Michelle A. Baker Jan 2007

Discontinuities In Stream Nutrient Uptake Below Lakesin Mountain Drainage Networks, Michelle A. Baker

Michelle A. Baker

In many watersheds, lakes and streams are hydrologically linked in spatial patterns that influence material transport and retention. We hypothesized that lakes affect stream nutrient cycling via modifications to stream hydrogeomorphology, source‐waters, and biological communities. We tested this hypothesis in a lake district of the Sawtooth Mountains, Idaho. Uptake of NO3− and PO4−3 was compared among 25 reaches representing the following landscape positions: lake inlets and outlets, reaches >1‐km downstream from lakes, and reference reaches with no nearby lakes. We quantified landscape‐scale hydrographic and reach‐scale hydrogeomorphic, source‐water, and biological variables to characterize these landscape positions and analyze relationships to nutrient …


Hydrophobic, Organically-Modified Silica Gels Enhance The Structure Of Encapsulated Apomyoglobin, Daryl K. Eggers, V. A. Rocha Jan 2007

Hydrophobic, Organically-Modified Silica Gels Enhance The Structure Of Encapsulated Apomyoglobin, Daryl K. Eggers, V. A. Rocha

Daryl K. Eggers

Insertion of hydrophobic groups in a silica matrix, by addition of propyl- or trifluoropropyltrimethoxysilane, leads to a surprising increase in the helical content of apomyoglobin following encapsulation by the sol–gel technique


Volitional Control Of Attention And Brain Activation In Dual Task Performance, Sharlene Newman, Timothy Keller, Marcel Just Dec 2006

Volitional Control Of Attention And Brain Activation In Dual Task Performance, Sharlene Newman, Timothy Keller, Marcel Just

Marcel Adam Just

No abstract provided.


Inhibitory Control In High Functioning Autism: Decreased Activation And Underconnectivity In Inhibition Networks, Rajesh Kana, Timothy Keller, Nancy Minshew, Marcel Just Dec 2006

Inhibitory Control In High Functioning Autism: Decreased Activation And Underconnectivity In Inhibition Networks, Rajesh Kana, Timothy Keller, Nancy Minshew, Marcel Just

Marcel Adam Just

No abstract provided.


Chess, Chance And Conspiracy, Mark Segal Dec 2006

Chess, Chance And Conspiracy, Mark Segal

Mark R Segal

Chess and chance are seemingly strange bedfellows. Luck and/or randomness have no apparent role in move selection when the game is played at the highest levels. However, when competition is at the ultimate level, that of the World Chess Championship (WCC), chess and conspiracy are not strange bedfellows, there being a long and colorful history of accusations levied between participants. One such accusation, frequently repeated, was that all the games in the 1985 WCC (Karpov vs Kasparov) were fixed and prearranged move by move. That this claim was advanced by a former World Champion, Bobby Fischer, argues that it ought …


The Extracellular Chaperone Clusterin Influences Amyloid Formation And Toxicity By Interacting With Pre-Fibrillar Structures, Justin Yerbury, Stephen Poon, Sarah Meehan, Brianna Thompson, Janet Kumita, Christopher Dobson, Mark Wilson Dec 2006

The Extracellular Chaperone Clusterin Influences Amyloid Formation And Toxicity By Interacting With Pre-Fibrillar Structures, Justin Yerbury, Stephen Poon, Sarah Meehan, Brianna Thompson, Janet Kumita, Christopher Dobson, Mark Wilson

Mark R Wilson

Clusterin is an extracellular chaperone present in all disease-associated extracellular amyloid deposits, however, its roles in amyloid formation and protein deposition in vivo are poorly understood. The current study initially aimed to characterise the effects of clusterin on amyloid formation in vitro by a panel of eight protein substrates. Two of the substrates (Alzheimer's beta peptide and a PI3-SH3 domain) were then used in further experiments to examine the effects of clusterin on amyloid cytotoxicity and to probe the mechanism of clusterin action. We show that clusterin exerts potent effects on amyloid formation, the nature and extent of which vary …


The Extracellular Chaperone Clusterin Potently Inhibits Human Lysozyme Amyloid Formation By Interacting With Prefibrillar Species, Mark Wilson, Justin Yerbury, Stephen Poon, Christopher Dobson, C V Robinson, Elise Stewart, Janet Kumita, Mireille Dumoulin, Gemma Caddy, Christine Hagan Dec 2006

The Extracellular Chaperone Clusterin Potently Inhibits Human Lysozyme Amyloid Formation By Interacting With Prefibrillar Species, Mark Wilson, Justin Yerbury, Stephen Poon, Christopher Dobson, C V Robinson, Elise Stewart, Janet Kumita, Mireille Dumoulin, Gemma Caddy, Christine Hagan

Mark R Wilson

We have studied the effects of the extracellular molecular chaperone, clusterin, on the in vitro aggregation of mutational variants of human lysozyme, including one associated with familial amyloid disease. The aggregation of the amyloidogenic variant I56T is inhibited significantly at clusterin-to-lysozyme ratios as low as 1:80 (i.e. one clusterin molecule per 80 lysozyme molecules). Experiments indicate that under the conditions where inhibition of aggregation occurs, clusterin does not bind detectably to the native or fibrillar states, or to the monomeric transient intermediate known to be a key species in the aggregation reaction. Rather, it seems to interact with oligomeric species …


Effects Of Glycosylation On The Structure And Function Of The Extracellular Chaperone Clusterin, Elise Stewart, Andrew Aquilina, Simon B Easterbrook-Smith, D Murphy-Durland, C Jacobsen, S Moestrup, Mark Wilson Dec 2006

Effects Of Glycosylation On The Structure And Function Of The Extracellular Chaperone Clusterin, Elise Stewart, Andrew Aquilina, Simon B Easterbrook-Smith, D Murphy-Durland, C Jacobsen, S Moestrup, Mark Wilson

Mark R Wilson

Clusterin is the first well characterized, constitutively secreted extracellular chaperone that binds to exposed regions of hydrophobicity on non-native proteins. It may help control the folding state of extracellular proteins by targeting them for receptor-mediated endocytosis and intracellular lysosomal degradation. A notable feature of secreted clusterin is its heavy glycosylation. Although carbohydrate comprises approximately 20−25% of the total mass of the mature molecule, its function is unknown. Results from the current study demonstrate that deglycosylation of human serum clusterin had little effect on its overall secondary structure content but produced a small increase in solvent-exposed hydrophobicity and enhanced the propensity …


Computational Modeling Of Calcium Dynamics Near Heterogeneous Release Sites, Borbala Mazzag, Zachary Cooper, Michael Greenwood Dec 2006

Computational Modeling Of Calcium Dynamics Near Heterogeneous Release Sites, Borbala Mazzag, Zachary Cooper, Michael Greenwood

Borbala Mazzag

Background: Calcium is known to play an important role in many physiological
processes, such as egg fertilization and heart muscle functions.
Several recent theoretical studies ([4], [1]) investigated calcium dynamics
near so-called release sites – clusters of calcium-regulated channels on
the intracellular calcium stores. Interest in the synchronized openings of
channels within a release site has increased because these openings are
thought to be the building blocks of global calcium events.
Methods: We conduct computational studies of the effect of heterogeneity
in the make-up of the release site on the resulting calcium dynamics.
We introduce heterogeneity into the model of …


Brain Activation During Sentence Comprehension Among Good And Poor Readers, Ann Meyler, Timothy A. Keller, Vladimir L. Cherkassky, Donghoon Lee, Fumiko Hoeft, Susan Whitfield-Gabrieli, John D. E. Gabrieli, Marcel Adam Just Dec 2006

Brain Activation During Sentence Comprehension Among Good And Poor Readers, Ann Meyler, Timothy A. Keller, Vladimir L. Cherkassky, Donghoon Lee, Fumiko Hoeft, Susan Whitfield-Gabrieli, John D. E. Gabrieli, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Individual Differences In Sentence Comprehension: A Functional Magnetic Resonance Imaging Investigation Of Syntactic And Lexical Processing Demands, Chantel S. Prat, Timothy A. Keller, Marcel Adam Just Dec 2006

Individual Differences In Sentence Comprehension: A Functional Magnetic Resonance Imaging Investigation Of Syntactic And Lexical Processing Demands, Chantel S. Prat, Timothy A. Keller, Marcel Adam Just

Marcel Adam Just

No abstract provided.