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2004

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Articles 391 - 420 of 3873

Full-Text Articles in Physical Sciences and Mathematics

Ship-Based Nitric Acid Measurements In The Gulf Of Maine During New England Air Quality Study 2002, Jack E. Dibb, Eric Scheuer, Sallie I. Whitlow, Marcy Vozzella, Eric Williams, Brian M. Lerner Oct 2004

Ship-Based Nitric Acid Measurements In The Gulf Of Maine During New England Air Quality Study 2002, Jack E. Dibb, Eric Scheuer, Sallie I. Whitlow, Marcy Vozzella, Eric Williams, Brian M. Lerner

Earth Sciences

Gas phase nitric acid (HNO3) was measured at 5-min resolution on board the National Oceanographic and Atmospheric Administration (NOAA) research vessel Ronald H. Brown during the second leg (29 July to 10 August) of the New England Air Quality Study (NEAQS) 2002 cruise. A primary objective of the cruise was to improve understanding of the oxidation of NOx in, and removal of the oxidation products from, the polluted marine boundary layer east of northeastern North America. For the first 9 days of this leg the ship remained north of Cape Cod, and the cruise track did not …


2004 Forage Spokesperson Contestants, James Chestnut, Jimmy May, Steve Meredith, Bill Payne Oct 2004

2004 Forage Spokesperson Contestants, James Chestnut, Jimmy May, Steve Meredith, Bill Payne

Kentucky Grazing Conference

No abstract provided.


Strategies For Reducing Stored Feed Requirements, Don Ball Oct 2004

Strategies For Reducing Stored Feed Requirements, Don Ball

Kentucky Grazing Conference

A basic, desirable goal for virtually any livestock producer is to minimize stored feed requirements. It is less expensive to have livestock harvest forage for themselves by grazing than to harvest it for them; therefore, the greater the extent to which pasture can be used to provide nutrition, the more profitable a livestock operation will generally be. Thus, it is worthwhile to consider all options that might be available for reducing stored feed needs.


Stocking Decisions: They Make Or Break You, Glen E. Aiken Oct 2004

Stocking Decisions: They Make Or Break You, Glen E. Aiken

Kentucky Grazing Conference

Decisions on species and variety of forage to plant and manage are economically critical because it establishes the potential to meet a particular production goal. However, the stocking rate used to graze these forages is more critical because it ultimately determines if a targeted level of production is reached. Most cattlemen aim for a stocking rate that provides maximum economic return, but it should be emphasized that an economically optimum stocking rate is one that potentially provides sustained economic return. It is obvious that dollar return is not maximized if excessive heavy grazing results in costly pasture renovation, ranging from …


Grazing: Getting From Where You Are To Where You Want To Be, Gary Bates Oct 2004

Grazing: Getting From Where You Are To Where You Want To Be, Gary Bates

Kentucky Grazing Conference

When trying to design a forage and grazing program, producers often try to consider so many factors that it becomes mind-boggling. If basic plant physiology, how and when a forage plant grows is considered, improving a forage program will usually become easier, especially in developing a controlled grazing system. The purpose of a controlled grazing system should be to improve the utilization of the high quality forage produced on the farm. In order to improve this utilization, it is helpful to understand plant growth and quality, and the factors that affect them.


Will Improved Grazing Pay For Extra Fencing And Water Cost?, Ken Johnson Oct 2004

Will Improved Grazing Pay For Extra Fencing And Water Cost?, Ken Johnson

Kentucky Grazing Conference

Expectation is founded on faith, and in faith lays opportunities. I suppose as we look at most farming operations most changes occur from force not by choice. What I propose today and hope to convince most of you; is that here is an opportunity to make more profit, if you’re willing to change and have faith that it will work. Most of us have heard of, if not practiced rotation grazing for a long time. The question many ask, is it worthwhile. Does better grazing management make me any more money? I hope to at least provide some insight as …


Present And Future Tall Fescue Varieties, Timothy D. Phillips Oct 2004

Present And Future Tall Fescue Varieties, Timothy D. Phillips

Kentucky Grazing Conference

Tall fescue has played a key role in forage production over the past century in the USA. It has other uses besides forage applications, such as turf, mine reclamation, and highway rights-of-way, but in this presentation we will focus on forage varieties. Several hundred turf-type tall fescue varieties have been developed over the past 30 years, mainly by private seed companies using material from Reed Funk at Rutgers University in New Jersey. Forage varieties aren’t as numerous. I will discuss some of the older and current forage tall fescue varieties, and finish by discussing the newest varieties, and those that …


Fertilizing Pastures For Profit, Byron Sleugh Oct 2004

Fertilizing Pastures For Profit, Byron Sleugh

Kentucky Grazing Conference

It has been known for centuries that providing certain nutrients to plants is critical for high productivity. The nutrient source and manner in which it is applied may vary, but the desired outcome is the same: high crop yield and quality. Fertilization is the most practical means that producers have to ensure that crops receive the nutrients they need. While increasing fertilizer application and managing pH by liming can lead to increase forage production, your investment should be measured against the potential return. Also, over application of nutrients can potentially cause environmental problems.


Role Of Legumes In Pasture Systems, Garry D. Lacefield Oct 2004

Role Of Legumes In Pasture Systems, Garry D. Lacefield

Kentucky Grazing Conference

Successful livestock programs are dependent on forage programs which supply large quantities of adequate quality, homegrown feed. A major percentage of the feed units for beef (83%) and dairy (61%) cattle come from forages. In addition, forages supply an estimated 91%, 72%, 15% and 99% of the nutrients consumed by sheep and goats, horses, swine and ruminant wildlife, respectively. These values can be put in perspective when we consider that 63% of Kentucky's Agricultural Cash Receipts are from livestock and livestock products. Cash hay accounts for approximately 28% of the total crop value. Hay ranks second only to tobacco in …


Foreword And Kfgc Award Winners [2004], Garry D. Lacefield, Christi L. Forsythe Oct 2004

Foreword And Kfgc Award Winners [2004], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.


Multiple Testing And Data Adaptive Regression: An Application To Hiv-1 Sequence Data, Merrill D. Birkner, Sandra E. Sinisi, Mark J. Van Der Laan Oct 2004

Multiple Testing And Data Adaptive Regression: An Application To Hiv-1 Sequence Data, Merrill D. Birkner, Sandra E. Sinisi, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Analysis of viral strand sequence data and viral replication capacity could potentially lead to biological insights regarding the replication ability of HIV-1. Determining specific target codons on the viral strand will facilitate the manufacturing of target specific antiretrovirals. Various algorithmic and analysis techniques can be applied to this application. We propose using multiple testing to find codons which have significant univariate associations with replication capacity of the virus. We also propose using a data adaptive multiple regression algorithm to obtain multiple predictions of viral replication capacity based on an entire mutant/non-mutant sequence profile. The data set to which these techniques …


Surface Structure Of Ultrathin Copolymer Films Of Ferroelectric Vinylidene Fluoride (70%) With Trifluoroethylene (30%) On Graphite, Lei Cai, Hongwei Qu, Chenxi Lu, Stephen Ducharme, Peter A. Dowben, Jiandi Zhang Oct 2004

Surface Structure Of Ultrathin Copolymer Films Of Ferroelectric Vinylidene Fluoride (70%) With Trifluoroethylene (30%) On Graphite, Lei Cai, Hongwei Qu, Chenxi Lu, Stephen Ducharme, Peter A. Dowben, Jiandi Zhang

Department of Physics and Astronomy: Faculty Publications

The structure and local structural distortions, through the polarization manipulation, of crystalline films of ferroelectric vinylidene fluoride (70%) with trifluoroethylene (30%) [P(VDF-TrFE)] copolymer on graphite were studied by scanning tunneling microscopy (STM). A quasispiral twist in C[Single Bond]C bonds with rotations about the polymer chain axis was observed by high-resolution STM, indicating a surface relaxation of the strained copolymer films. Such a relaxation behavior appears to be linked to the observed local dipole rotations accompanied by the reversal of the local polarization with biasing the STM tip. A structure model is proposed based upon the observations


Evaluation And Management Of Chronic Wasting Disease Transmission, Kurt C. Vercauteren Oct 2004

Evaluation And Management Of Chronic Wasting Disease Transmission, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

National Wildlife Research Center Scientists Assess the Potential for Chronic Wasting Disease (CWD) Transmission Between Wild and Domestic Cervids and Develop Methods to Reduce/Manage the Disease

Wildlife Services’ (WS) National Wildlife Research Center (NWRC) is the only Federal research organization devoted exclusively to resolving conflicts between people and wildlife through the development of effective, selective, and acceptable methods, tools, and techniques. As increased urbanization leads to a loss of traditional wildlife habitat, the potential for conflicts between people and wildlife increases. Such conflicts can take many forms, but recently the potential for the transmission of diseases among wildlife, livestock, and …


Ultra-Fast Formation Of Stable Nanoparticle Film Assemblies, Dan Sheibley, Renee Szymanik, Michael C. Leopold Oct 2004

Ultra-Fast Formation Of Stable Nanoparticle Film Assemblies, Dan Sheibley, Renee Szymanik, Michael C. Leopold

Chemistry Faculty Publications

Novel assembled films of monolayer-protected clusters (MPCs) can be grown on gold and glass substrates with a 20-fold higher efficiency than established procedures. Thick MPC films grown using this new method, which can easily be scaled up or automated, are extremely stable and have properties identical to traditionally formed nanoparticle films, including unique quantized double layer charging effects. This new procedure for growing nanoparticle films shares the versatility of the traditional method but exhibits accelerated growth attributed to highly efficient sorption and mobility of metal ion linkers within swelled films and improved mass transfer of nanoparticles to assembly sites. Concentration …


Gllamm Manual, Sophia Rabe-Hesketh, Anders Skrondal, Andrew Pickles Oct 2004

Gllamm Manual, Sophia Rabe-Hesketh, Anders Skrondal, Andrew Pickles

U.C. Berkeley Division of Biostatistics Working Paper Series

This manual describes a Stata program gllamm that can estimate Generalized Linear Latent and Mixed Models (GLLAMMs). GLLAMMs are a class of multilevel latent variable models for (multivariate) responses of mixed type including continuous responses, counts, duration/survival data, dichotomous, ordered and unordered categorical responses and rankings. The latent variables (common factors or random effects) can be assumed to be discrete or to have a multivariate normal distribution. Examples of models in this class are multilevel generalized linear models or generalized linear mixed models, multilevel factor or latent trait models, item response models, latent class models and multilevel structural equation models. …


Assessment Of Engineering Mechanics Instructional Multimedia In A Variety Of Instructional Settings, Richard H. Hall, Nancy Hubing, Timothy A. Philpot, Ralph E. Flori, Vikas Yellamraju Oct 2004

Assessment Of Engineering Mechanics Instructional Multimedia In A Variety Of Instructional Settings, Richard H. Hall, Nancy Hubing, Timothy A. Philpot, Ralph E. Flori, Vikas Yellamraju

Business and Information Technology Faculty Research & Creative Works

Students from Ten Schools, Representing Seven Countries, Used Interactive Multimedia as a Part of their Engineering Statics Classes. the Software Consisted of Four Modules, Which Focused On: Mohr's Circle; Centroid and Moment of Inertia; Stress Transformation; and Structural Analysis. the Students Completed On-Line Surveys About their Experience with the Software. Analysis of the Results Indicated that Students Rated their Knowledge of the Subject Matter Covered in the Software as Increasing Significantly as a Consequence of using the Software. However, This Increase Was Substantially More Pronounced for Students in U.S. Schools. Students Rated the Software as Significantly More Effective Than their …


Development Of A High Performance Liquid Chromatography/Mass Spectroscopy Method For The Determination Of Strychnine Concentrations In Insects Used To Assess Potential Risks To Insectivores, Randal S. Stahl, Wendy M. Arjo, Kim K. Wagner, Carol Furcolow, Dale L. Nolte, John J. Johnston Oct 2004

Development Of A High Performance Liquid Chromatography/Mass Spectroscopy Method For The Determination Of Strychnine Concentrations In Insects Used To Assess Potential Risks To Insectivores, Randal S. Stahl, Wendy M. Arjo, Kim K. Wagner, Carol Furcolow, Dale L. Nolte, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

A high performance liquid chromatography/mass spectrometry (HPLC/MS) method was developed in support of a study to assess potential tertiary risks posed to insectivores by strychnine baited pocket gophers (Thomomys sp.). Necropholous insects are primary consumers of pocket gopher carcasses. A field study was conducted to collect insects from strychnine-baited and control pocket gopher carcasses. The majority of the insects collected were from the orders Diptera (flies, assayed separately as adults and larvae), Coleoptera (beetles), and Hymenoptera (ants and wasps, assayed separately). Samples (0.5 g) were extracted in acetic acid (2%) and analyzed with the mass spectrometer configured for tandem …


Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix, Spencer M. Steinberg, Gary Cerefice, David W. Emerson Oct 2004

Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix, Spencer M. Steinberg, Gary Cerefice, David W. Emerson

Separations Campaign (TRP)

The recovery of iodine released during the processing of used nuclear fuel poses a significant challenge to the transmutation of radioactive iodine. During the first two years of this program we have examined the potential of Fullerene Containing Carbon compounds (FCC) developed by KRI, and natural organic matter (NOM) as sorbents for iodine released during the reprocessing of nuclear fuel. This work involved the development of bench-scale testing of the FCC and NOM material in a simulated process off-gas environment.

Research Objectives and Goals

• Develop bench-scale experimental set-up and procedures for simulating PUREX head-end vapor phase; Develop experimental procedures …


Hybrid Atomistic-Coarse-Grained Treatment Of Thin-Film Lubrication. Ii, Z.-B. Wu, Dennis J. Diestler, Xiao Cheng Zeng Oct 2004

Hybrid Atomistic-Coarse-Grained Treatment Of Thin-Film Lubrication. Ii, Z.-B. Wu, Dennis J. Diestler, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

A new hybrid atomistic-coarse-grained (HACG) treatment of reversible processes in multiple-scale systems involving fluid-solid interfaces was tested through isothermal-isobaric Monte Carlo simulations of the quasistatic shearing of a model two-dimensional lubricated contact comprising two planar Lennard-Jones solid substrates that sandwich a softer Lennard-Jones film. Shear-stress profiles (plots of shear stress Tyx versus lateral displacement of the substrates) obtained by the HACG technique, which combines an atomistic description of the interfacial region with a continuum description of regions well removed from the interface, are compared with “exact” profiles (obtained by treating the whole system at the atomic scale) for a …


Melting Points And Thermal Expansivities Of Proton-Disordered Hexagonal Ice With Several Model Potentials, Yuji Koyama, Hideki Tanaka, Guangtu Gao, Xiao Cheng Zeng Oct 2004

Melting Points And Thermal Expansivities Of Proton-Disordered Hexagonal Ice With Several Model Potentials, Yuji Koyama, Hideki Tanaka, Guangtu Gao, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

A method of free energy calculation is proposed, which enables to cover a wide range of pressure and temperature. The free energies of proton-disordered hexagonal ice (ice Ih) and liquid water are calculated for the TIP4P [J. Chem. Phys. 79, 926 (1983)] model and the TIP5P @J. Chem. Phys. 112, 8910 (2000) model. From the calculated free energy curves, we determine the melting point of the proton-disordered hexagonal ice at 0.1 MPa (atmospheric pressure), 50 MPa, 100 MPa, and 200 MPa. The melting temperatures at atmospheric pressure for the TIP4P ice and the TIP5P ice are found to be about …


Computing The M = 1 Diocotron Frequency Via An Equilibrium Calculation In Non-Neutral Plasmas, Ross L. Spencer Oct 2004

Computing The M = 1 Diocotron Frequency Via An Equilibrium Calculation In Non-Neutral Plasmas, Ross L. Spencer

Faculty Publications

The m = 1 diocotron mode in non-neutral plasmas has long been thought of as a shifted equilibrium, and its frequency has been approximately calculated in this way by Fine and Driscoll [Phys. Plasmas 5, 601 (1998)]. This article shows that this idea can be coupled with a standard axisymmetric equilibrium calculation on a grid to calculate the frequency of this mode to very high precision including both finite-length and thermal effects, provided that the Debye length is small enough. As the Debye length begins to approach the plasma size not only does the shifted equilibrium calculation fail to predict …


Composing A Well-Typed Region, Chris Hawblitzel, Heng Huang, Lea Wittie Oct 2004

Composing A Well-Typed Region, Chris Hawblitzel, Heng Huang, Lea Wittie

Computer Science Technical Reports

Efficient low-level systems need more control over memory than safe high-level languages usually provide. In particular, safe languages usually prohibit explicit deallocation, in order to prevent dangling pointers. Regions provide one safe deallocation mechanism; indeed, many region calculi have appeared recently, each with its own set of operations and often complex rules. This paper encodes regions from lower-level typed primitives (linear memory, coercions, and delayed types), so that programmers can design their own region operations and rules.


Disk Based Model Checking, Tonglaga Bao Oct 2004

Disk Based Model Checking, Tonglaga Bao

Theses and Dissertations

Disk based model checking does not receive much attention in the model checking field becasue of its costly time overhead. In this thesis, we present a new disk based algorithm that can get close to or faster verification speed than a RAM based algorithm that has enough memory to complete its verification. This algorithm also outperforms Stern and Dill's original disk based algorithm. The algorithm partitions the state space to several files, and swaps files into and out of memory during verification. Compared with the RAM only algorithm, the new algoritm reduces hash table insertion time by reducing the cost …


Direct Photon Cross Section With Conversions At Cdf, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Oct 2004

Direct Photon Cross Section With Conversions At Cdf, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We present a measurement of the isolated direct photon cross section in pp̅ collisions at √s =1.8 TeV and |η|0→γγ and η→γγ events from the data we use a new background subtraction technique which takes advantage of the tracking information available in a photon conversion event. We find that the shape of the cross section as a function of photon pT is poorly described by next-to-leading-order QCD predictions, but agrees with previous CDF measurements.


Data Adaptive Estimation Of The Treatment Specific Mean, Yue Wang, Oliver Bembom, Mark J. Van Der Laan Oct 2004

Data Adaptive Estimation Of The Treatment Specific Mean, Yue Wang, Oliver Bembom, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

An important problem in epidemiology and medical research is the estimation of the causal effect of a treatment action at a single point in time on the mean of an outcome, possibly within strata of the target population defined by a subset of the baseline covariates. Current approaches to this problem are based on marginal structural models, i.e., parametric models for the marginal distribution of counterfactural outcomes as a function of treatment and effect modifiers. The various estimators developed in this context furthermore each depend on a high-dimensional nuisance parameter whose estimation currently also relies on parametric models. Since misspecification …


Finding Cancer Subtypes In Microarray Data Using Random Projections, Debashis Ghosh Oct 2004

Finding Cancer Subtypes In Microarray Data Using Random Projections, Debashis Ghosh

The University of Michigan Department of Biostatistics Working Paper Series

One of the benefits of profiling of cancer samples using microarrays is the generation of molecular fingerprints that will define subtypes of disease. Such subgroups have typically been found in microarray data using hierarchical clustering. A major problem in interpretation of the output is determining the number of clusters. We approach the problem of determining disease subtypes using mixture models. A novel estimation procedure of the parameters in the mixture model is developed based on a combination of random projections and the expectation-maximization algorithm. Because the approach is probabilistic, our approach provides a measure for the number of true clusters …


Semiparametric Methods For The Binormal Model With Multiple Biomarkers, Debashis Ghosh Oct 2004

Semiparametric Methods For The Binormal Model With Multiple Biomarkers, Debashis Ghosh

The University of Michigan Department of Biostatistics Working Paper Series

Abstract: In diagnostic medicine, there is great interest in developing strategies for combining biomarkers in order to optimize classification accuracy. A popular model that has been used when one biomarker is available is the binormal model. Extension of the model to accommodate multiple biomarkers has not been considered in this literature. Here, we consider a multivariate binormal framework for combining biomarkers using copula functions that leads to a natural multivariate extension of the binormal model. Estimation in this model will be done using rank-based procedures. We also discuss adjustment for covariates in this class of models and provide a simple …


Long-Term Mechanical Behavior Of Yucca Mountain Tuffs, And Its Variability, Jaak J.K. Daemen, George Danko, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler Oct 2004

Long-Term Mechanical Behavior Of Yucca Mountain Tuffs, And Its Variability, Jaak J.K. Daemen, George Danko, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

We propose to continue the investigation of the long term strength of Yucca Mountain tuffs, with particular emphasis on tuffs from and near the emplacement horizon. We propose to also continue and expand the investigation of the spatial variability of rock strength and stiffness. An intrinsic component of this planned rock testing is the testing of rock joints. Although the emphasis is on tests aimed at determining long term strength, as part of the testing measurements of stiffness also are collected, and will be collected, reported, and analyzed.


Survey And Census Techniques For Canids, E. M. Gese Oct 2004

Survey And Census Techniques For Canids, E. M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

We already know that the status and distribution of canid populations throughout the world is of growing concern for biologists and the public alike. Habitat loss, fragmentation and degradation, human persecution, decreases in prey, disease, poaching, and increased competition with other carnivores due to reduced space and habitat, have led to some canid species facing extinction, while others occupy only a fraction of their former range. While reintroductions of some species have been successful (e.g., grey wolves Canis lupus to the Northern Rockies of the U.S.), other species face an uncertain future (e.g., African wild dogs Lycaon pictus). Paramount …


Location Of The Optical Reverse Shock In The Cassiopeia A Supernova Remnant, Jon A. Morse, Robert A. Fesen, Roger A. Chevalier, Kazimierz J. Borkowski Oct 2004

Location Of The Optical Reverse Shock In The Cassiopeia A Supernova Remnant, Jon A. Morse, Robert A. Fesen, Roger A. Chevalier, Kazimierz J. Borkowski

Dartmouth Scholarship

We use two epochs of Hubble Space Telescope WFPC2 images separated by 2 yr to determine the location and propagation of the reverse shock (RS) in the young supernova remnant Cassiopeia A (Cas A). The images trace optical line emission from fast-moving knots and filaments of highly processed ejecta as they cross the RS, become heated and compressed, and radiatively cool. At numerous positions around the optical shell, new emission features are seen in the 2002 images that were not yet visible in the 2000 exposures. In a few instances emission features seen in the first epoch have completely disappeared …