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6th Annual Systems Biology Symposium: Systems Biology and the Environment (open access)

6th Annual Systems Biology Symposium: Systems Biology and the Environment

Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology is an annual two-day event gathering the most influential researchers transforming biology into an integrative discipline investigating complex systems. In recognition of the fundamental similarity between the scientific problems addressed in environmental science and systems biology studies at the molecular, cellular, and organismal levels, the 2007 Symposium featured global leaders in “Systems Biology and the Environment.” The objective of the 2007 “Systems Biology and the Environment” International Symposium was to stimulate interdisciplinary thinking and research that spans systems biology and environmental science. This Symposium was well aligned with the DOE’s Genomics:GTL program efforts to achieve scientific objectives for each of the three DOE missions: • Develop biofuels as a major secure energy source for this century, • Develop biological solutions for intractable environmental problems, and • Understand biosystems’ climate impacts and assess sequestration strategies Our scientific program highlighted world-class research exemplifying these priorities. The Symposium featured 45 minute lectures from 12 researchers including: Penny/Sallie Chisholm of MIT gave the keynote address “Tiny Cells, Global Impact: What Prochlorococcus Can Teach Us About Systems Biology”, plus Jim Fredrickson of PNNL, Nitin Baliga …
Date: April 1, 2007
Creator: Galitski, Timothy, P.
System: The UNT Digital Library
An Architecture Proposal for the ILC Test Beam Silicon Telescope at Fermilab (open access)

An Architecture Proposal for the ILC Test Beam Silicon Telescope at Fermilab

The requirements for an ILC Test Beam silicon telescope system are foreseen to be very stringent. Resolution, noise, and throughput must be carefully managed in order to provide a useful instrument for the high energy physics community to develop detector technologies for the ILC. Since the ILC Test Beam is meant to test a wide variety of different detectors, it must employ universally accepted software techniques, hardware standards and protocols as well as easy integration of hardware and software with the various clients using the system. In this paper, we describe an open modular architecture to achieve these goals, including an analysis of the entire chain of software and hardware needed to meet the requirements.
Date: April 1, 2007
Creator: Turqueti, M.A.
System: The UNT Digital Library
Beam Condition Monitoring with Diamonds at CDF (open access)

Beam Condition Monitoring with Diamonds at CDF

This report talks Beam Condition Monitoring with Diamonds at CDF
Date: April 1, 2007
Creator: Dong, Peter; Eusebi, Ricardo; Schrupp, Charlie; Sfyrla, Anna; Tesarek, Rick & Wallny, Rainer
System: The UNT Digital Library
Biocompatible Silver-containing a-C:H and a-C coatings: AComparative Study (open access)

Biocompatible Silver-containing a-C:H and a-C coatings: AComparative Study

Hydrogenated diamond-like-carbon (a-C:H) and hydrogen-free amorphous carbon (a-C) coatings are known to be biocompatible and have good chemical inertness. For this reason, both of these materials are strong candidates to be used as a matrix that embeds metallic elements with antimicrobial effect. In this comparative study, we have incorporated silver into diamond-like carbon (DLC) coatings by plasma based ion implantation and deposition (PBII&D) using methane (CH4) plasma and simultaneously depositing Ag from a pulsed cathodic arc source. In addition, we have grown amorphous carbon - silver composite coatings using a dual-cathode pulsed filtered cathodic-arc (FCA) source. The silver atomic content of the deposited samples was analyzed using glow discharge optical spectroscopy (GDOES). In both cases, the arc pulse frequency of the silver cathode was adjusted in order to obtain samples with approximately 5 at.% of Ag. Surface hardness of the deposited films was analyzed using the nanoindentation technique. Cell viability for both a-C:H/Ag and a-C:/Ag samples deposited on 24-well tissue culture plates has been evaluated.
Date: April 1, 2007
Creator: Endrino, Jose Luis; Allen, Matthew; Escobar Galindo, Ramon; Zhang, Hanshen; Anders, Andre & Albella, Jose Maria
System: The UNT Digital Library
[Brilliant Magazine Excerpt, April 2007] (open access)

[Brilliant Magazine Excerpt, April 2007]

Article published in Brilliant Magazine about travel and attractions in Belize.
Date: April 2007
Creator: Brilliant Magazine
System: The UNT Digital Library
Carbon Dioxide Separation with Supported Ionic Liquid Membranes (open access)

Carbon Dioxide Separation with Supported Ionic Liquid Membranes

Supported liquid membranes are a class of materials that allow the researcher to utilize the wealth of knowledge available on liquid properties as a direct guide in the development of a capture technology. These membranes also have the advantage of liquid phase diffusivities higher than those observed in polymeric membranes which grant proportionally greater permeabilities. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high carbon dioxide solubility relative to light gases such as hydrogen, are an excellent candidate for this type of membrane since they have negligible vapor pressure and are not susceptible to evaporation. A study has been conducted evaluating the use of several ionic liquids, including 1-hexyl-3-methyl-imidazolium bis(trifuoromethylsulfonyl)imide, 1-butyl-3-methyl-imidazolium nitrate, and 1-ethyl-3-methyl-imidazolium sulfate in supported ionic liquid membranes for the capture of carbon dioxide from streams containing hydrogen. In a joint project, researchers at the University of Notre Dame lent expertise in ionic liquid synthesis and characterization, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance. Initial results have been very promising with carbon …
Date: April 1, 2007
Creator: Luebke, David R.; Ilconich, Jeffery B.; Myers, Christina R. & Pennline, Henry W.
System: The UNT Digital Library
The CDF II 3D-Track Level 2 Trigger Upgrade (open access)

The CDF II 3D-Track Level 2 Trigger Upgrade

None
Date: April 1, 2007
Creator: Ivanov, A.G.
System: The UNT Digital Library
Challenges for MSSM Higgs searches at hadron colliders (open access)

Challenges for MSSM Higgs searches at hadron colliders

In this article we analyze the impact of B-physics and Higgs physics at LEP on standard and non-standard Higgs bosons searches at the Tevatron and the LHC, within the framework of minimal flavor violating supersymmetric models. The B-physics constraints we consider come from the experimental measurements of the rare B-decays b {yields} s{gamma} and B{sub u} {yields} {tau}{nu} and the experimental limit on the B{sub s} {yields} {mu}{sup +}{mu}{sup -} branching ratio. We show that these constraints are severe for large values of the trilinear soft breaking parameter A{sub t}, rendering the non-standard Higgs searches at hadron colliders less promising. On the contrary these bounds are relaxed for small values of A{sub t} and large values of the Higgsino mass parameter {mu}, enhancing the prospects for the direct detection of non-standard Higgs bosons at both colliders. We also consider the available ATLAS and CMS projected sensitivities in the standard model Higgs search channels, and we discuss the LHC's ability in probing the whole MSSM parameter space. In addition we also consider the expected Tevatron collider sensitivities in the standard model Higgs h {yields} b{bar b} channel to show that it may be able to find 3 {sigma} evidence in the …
Date: April 1, 2007
Creator: Carena, Marcela S.; Menon, A. & Wagner, C. E. M.
System: The UNT Digital Library
Chemical Gradients in Crud on Boiling Water Reactor Fuel Elements (open access)

Chemical Gradients in Crud on Boiling Water Reactor Fuel Elements

Crud (radioactive corrosion products formed inside nuclear reactors is a major problem in commercial power-producing nuclear reactors. Although there are numerous studies of simulated (non-radioactive) crud, characteristics of crud from actual reactors are rarely studied. This study reports scanning electron microscope (SEM) studies of fragments of crud from a commercially operating boiling water reactor. Chemical analyses in the SEM indicated that the crud closest to the outer surfaces of the fuel pins in some areas had Fe:Zn ratios close to 2:1, which decreased away from the fuel pin in some of the fragments. In combination with transmission electron microsope analyses (published elsewhere), these results suggest that the innermost layer of crud in some areas may consist of franklinite (ZnFe2O4, also called zinc spinel), while outer layers in these areas may be predominantly iron oxides.
Date: April 1, 2007
Creator: Porter, D. L. & Janney, D. E.
System: The UNT Digital Library
CMS DAQ event builder based on Gigabit Ethernet (open access)

CMS DAQ event builder based on Gigabit Ethernet

The CMS Data Acquisition System is designed to build and filter events originating from 476 detector data sources at a maximum trigger rate of 100 KHz. Different architectures and switch technologies have been evaluated to accomplish this purpose. Events will be built in two stages: the first stage will be a set of event builders called FED Builders. These will be based on Myrinet technology and will pre-assemble groups of about 8 data sources. The second stage will be a set of event builders called Readout Builders. These will perform the building of full events. A single Readout Builder will build events from 72 sources of 16 KB fragments at a rate of 12.5 KHz. In this paper we present the design of a Readout Builder based on TCP/IP over Gigabit Ethernet and the optimization that was required to achieve the design throughput. This optimization includes architecture of the Readout Builder, the setup of TCP/IP, and hardware selection.
Date: April 1, 2007
Creator: Bauer, G.; Boyer, V.; Branson, J.; Brett, A.; Cano, E.; Carboni, A. et al.
System: The UNT Digital Library
The Complete Genome Sequence of Bacillus thuringiensis AlHakam (open access)

The Complete Genome Sequence of Bacillus thuringiensis AlHakam

Bacillus thuringiensis is an insect pathogen that is widelyused as a biopesticide (3). Here we report the finished, annotated genomesequence of B. thuringiensis Al Hakam, which was collected in Iraq by theUnited Nations Special Commission (2).
Date: April 1, 2007
Creator: Challacombe, Jean F.; Altherr, Michael R.; Xie, Gary; Bhotika, Smriti S.; Brown, Nancy; Bruce, David et al.
System: The UNT Digital Library
CP violation studies at Tevatron (open access)

CP violation studies at Tevatron

We present an overview of a few recent results related to CP-violation from the Tevatron. First, we discuss a measurement of the dimuon charge asymmetry from D{O} , that extracts the CP-violation parameter of B{sup 0} mixing and decay. This is followed by the CDF measurement of the CP-violating asymmetry in B{sup 0} {yields} K{sup +}{pi}{sup -} decays. Finally we give the CDF result on the ratio R = BR(B{yields}D0K)/BR(B{yields}D0{pi}).
Date: April 1, 2007
Creator: Ben-Haim, E.
System: The UNT Digital Library
Current Comparison of Advanced Nuclear Fuel Cycles (open access)

Current Comparison of Advanced Nuclear Fuel Cycles

This paper compares potential nuclear fuel cycle strategies – once-through, recycling in thermal reactors, sustained recycle with a mix of thermal and fast reactors, and sustained recycle with fast reactors. Initiation of recycle starts the draw-down of weapons-usable material and starts accruing improvements for geologic repositories and energy sustainability. It reduces the motivation to search for potential second geologic repository sites. Recycle in thermal-spectru
Date: April 1, 2007
Creator: Piet, Steven; Bjornard, Trond; Dixon, Brent; Hill, Robert; Matthern, Gretchen & Shropshire, David
System: The UNT Digital Library
Direct Numerical Simulation of Boiling Multiphase Flows: State-of-the-Art, Modeling, Algorithmic and Computer Needs (open access)

Direct Numerical Simulation of Boiling Multiphase Flows: State-of-the-Art, Modeling, Algorithmic and Computer Needs

The state-of-the-art for Direct Numerical Simulation (DNS) of boiling multiphase flows is reviewed, focussing on potential of available computational techniques, the level of current success for their applications to model several basic flow regimes (film, pool-nucleate and wall-nucleate boiling -- FB, PNB and WNB, respectively). Then, we discuss multiphysics and multiscale nature of practical boiling flows in LWR reactors, requiring high-fidelity treatment of interfacial dynamics, phase-change, hydrodynamics, compressibility, heat transfer, and non-equilibrium thermodynamics and chemistry of liquid/vapor and fluid/solid-wall interfaces. Finally, we outline the framework for the {\sf Fervent} code, being developed at INL for DNS of reactor-relevant boiling multiphase flows, with the purpose of gaining insight into the physics of multiphase flow regimes, and generating a basis for effective-field modeling in terms of its formulation and closure laws.
Date: April 1, 2007
Creator: Nourgaliev, R.; Knoll, D.; Mousseau, V. & Berry, R.
System: The UNT Digital Library
Effects of Extreme Sleep Deprivation on Human Performance (open access)

Effects of Extreme Sleep Deprivation on Human Performance

Sleep is a fundamental recuperative process for the nervous system. Disruption of this homeostatic drive can lead to severe impairments of the operator’s ability to perceive, recognize, and respond to emergencies and/or unanticipated events, putting the operator at risk. Therefore, establishing a comprehensive understanding of how sleep deprivation influences human performance is essential in order to counter fatigue or to develop mitigation strategies. The goal of the present study was to examine the psychological effects of prolonged sleep deprivation (approx. 75 hrs) over a four-day span on a general aviation pilot flying a fixed-based flight simulator. During the study, a series of tasks were employed every four hours in order to examine the pilot’s perceptual and higher level cognitive abilities. Overall, results suggest that the majority of cognitive and perceptual degradation occurs between 30-40 hours into the flight. Limitations and future research directions are also discussed.
Date: April 1, 2007
Creator: Tran, Tuan; Raddatz, Kimberly R.; Cady, Elizabeth T.; Amstutz, Bradford; Elgin, Pete D.; Vowels, Christopher et al.
System: The UNT Digital Library
Evaluation of a Surface Treatment on the Performance of Stainless Steels for SOFC Interconnect Applications (open access)

Evaluation of a Surface Treatment on the Performance of Stainless Steels for SOFC Interconnect Applications

Pack cementation-like Cerium based surface treatments have been found to be effective in enhancing the oxidation resistance of ferritic steels (Crofer 22APU) for solid oxide fuel cell (SOFC) applications. The application of either a CeN- or CeO2 based surface treatment results in a decrease in weight gain by a factor of three after 4000 hours exposure to air+3%H2O at 800oC. Similar oxide scales formed on treated and untreated surfaces, with a continuous Cr-Mn outer oxide layer and a continuous inner Cr2O3 layer formed on the surface. However, the thickness of the scales, and the amount of internal oxidation were significantly reduced with the treatment, leading to the decrease in oxidation rate. This presentation will detail the influence of the treatment on the electrical properties of the interconnect. Half-cell experiments (LSM cathode sandwiched between two steel interconnects) and full SOFC button cell experiments were run with treated and untreated interconnects. Preliminary results indicate the Ce treatment can improve SOFC performance.
Date: April 1, 2007
Creator: Alman, D. E.; Holcomb, G. R.; Adler, T. A.; Wilson, R. W. & Jablonski, P. D.
System: The UNT Digital Library
Evolving the Nation's Energy Infrastructure: A Challenging System Issue for the Twenty-First Century; Preprint (open access)

Evolving the Nation's Energy Infrastructure: A Challenging System Issue for the Twenty-First Century; Preprint

Over the next several decades, a profound transformation of the global energy enterprise will occur driven largely by population growth and economic development. How this growing demand for energy is met poses one of the most complex and challenging issues of our time. The current national energy dialogue reflects the challenge in simultaneously considering the social, political, economic, and technical issues as the energy system is defined, technical targets are established, and programs and investments are implemented to meet those technical targets. This paper examines the general concepts and options for meeting this challenge.
Date: April 1, 2007
Creator: Garrett, B.
System: The UNT Digital Library
EXAMINATION OF THE PCICE METHOD IN THE NEARLY INCOMPRESSIBLE, AS WELL AS STRICTLY INCOMPRESSIBLE, LIMITS (open access)

EXAMINATION OF THE PCICE METHOD IN THE NEARLY INCOMPRESSIBLE, AS WELL AS STRICTLY INCOMPRESSIBLE, LIMITS

The conservative-form, pressure-based PCICE numerical method (Martineau and Berry, 2004) (Berry, 2006), recently developed for computing transient fluid flows of all speeds from very low to very high (with strong shocks), is simplified and generalized. Though the method automatically treats a continuous transition of compressibility, three distinct, limiting compressibility regimes are formally defined for purposes of discussion and comparison with traditional methods – the strictly incompressible limit, the nearly incompressible limit, and the f ully compressible limit. The PCICE method’s behavior is examined in each limiting regime. In the strictly incompressible limit the PCICE algorithm reduces to the traditional MAC-type method with velocity divergence driving the pressure Poisson equation. In the nearly incompressible limit the PCICE algorithm is found to reduce to a generalization of traditional incompressible methods, i.e. to one in which not only the velocity divergence effect, but also the density gradient effect is included as a driving function in the pressure Poisson equation. This nearly incompressible regime has received little attention, and it appears that in the past, strictly incompressible methods may have been conveniently applied to flows in this regime at the expense of ignoring a potentially important coupling mechanism. This could be significant in many …
Date: April 1, 2007
Creator: Berry, Ray A. & Martineau, Richard C.
System: The UNT Digital Library
Exploring the Variable Sky with the Sloan Digital Sky Survey (open access)

Exploring the Variable Sky with the Sloan Digital Sky Survey

We quantify the variability of faint unresolved optical sources using a catalog based on multiple SDSS imaging observations. The catalog covers SDSS Stripe 82, which lies along the celestial equator in the Southern Galactic Hemisphere (22h 24m < {alpha}{sub J2000} < 04h 08m, -1.27{sup o} < {delta}{sub J2000} < +1.27{sup o}, {approx} 290 deg{sup 2}), and contains 58 million photometric observations in the SDSS ugriz system for 1.4 million unresolved sources that were observed at least 4 times in each of the gri bands (with a median of 10 observations obtained over {approx}5 years). In each photometric bandpass we compute various low-order lightcurve statistics such as root-mean-square scatter (rms), {chi}{sup 2} per degree of freedom, skewness, minimum and maximum magnitude, and use them to select and study variable sources. We find that 2% of unresolved optical sources brighter than g = 20.5 appear variable at the 0.05 mag level (rms) simultaneously in the g and r bands. The majority (2/3) of these variable sources are low-redshift (< 2) quasars, although they represent only 2% of all sources in the adopted flux-limited sample. We find that at least 90% of quasars are variable at the 0.03 mag level (rms) and confirm …
Date: April 1, 2007
Creator: Sesar, Branimir; Ivezic, Zeljko; Lupton, Robert; Juric, Mario; Gunn, James; Knapp, Gillian et al.
System: The UNT Digital Library
Exploring the Variable Sky with the Sloan Digital Sky Survey (open access)

Exploring the Variable Sky with the Sloan Digital Sky Survey

We quantify the variability of faint unresolved optical sources using a catalog based on multiple SDSS imaging observations. The catalog covers SDSS Stripe 82, which lies along the celestial equator in the Southern Galactic Hemisphere (22h 24m < {alpha}{sub J2000} < 04h 08m, -1.27 < {delta}{sub J2000} < +1.27, {approx}290 deg{sup 2} ), and contains 58 million photometric observations in the SDSS ugriz system for 1.4 million unresolved sources that were observed at least 4 times in each of the gri bands (with a median of 10 observations obtained over {approx}5 years). In each photometric bandpass we compute various low-order lightcurve statistics such as root-mean-square scatter (rms), {chi}{sup 2} 2 per degree of freedom, skewness, minimum and maximum magnitude, and use them to select and study variable sources. We find that 2% of unresolved optical sources brighter than g = 20.5 appear variable at the 0.05 mag level (rms) simultaneously in the g and r bands. The majority (2/3) of these variable sources are low-redshift (< 2) quasars, although they represent only 2% of all sources in the adopted ux-limited sample. We find that at least 90% of quasars are variable at the 0.03 mag level (rms) and confirm that …
Date: April 1, 2007
Creator: Sesar, Branimir; Ivezic, Zeljko; Lupton, Robert H.; Juric, Mario; Gunn, James E.; Knapp, Gillian R. et al.
System: The UNT Digital Library
Fast digitization and discrimination of prompt neutron and photon signals using a novel silicon carbide detector (open access)

Fast digitization and discrimination of prompt neutron and photon signals using a novel silicon carbide detector

Current requirements of some Homeland Security active interrogation projects for the detection of Special Nuclear Material (SNM) necessitate the development of faster inspection and acquisition capabilities. In order to do so, fast detectors which can operate during and shortly after intense interrogation radiation flashes are being developed. Novel silicon carbide (SiC) semiconductor Schottky diodes have been utilized as robust neutron and photon detectors in both pulsed photon and pulsed neutron fields and are being integrated into active inspection environments to allow exploitation of both prompt and delayed emissions. These detectors have demonstrated the capability of detecting both photon and neutron events during intense photon flashes typical of an active inspection environment. Beyond the inherent insensitivity of SiC to gamma radiation, fast digitization and processing has demonstrated that pulse shape discrimination (PSD) in combination with amplitude discrimination can further suppress unwanted gamma signals and extract fast neutron signatures. Usable neutron signals have been extracted from mixed radiation fields where the background has exceeded the signals of interest by >1000:1.
Date: April 1, 2007
Creator: Blackburn, Brandon W.; Johnson, James T.; Watson, Scott M.; Chichester, David L.; Jones, James L.; Ruddy, Frank H. et al.
System: The UNT Digital Library
Flooded Underground Coal Mines: A Significant Source of Inexpensive Geothermal Energy (open access)

Flooded Underground Coal Mines: A Significant Source of Inexpensive Geothermal Energy

Many mining regions in the United States contain extensive areas of flooded underground mines. The water within these mines represents a significant and widespread opportunity for extracting low-grade, geothermal energy. Based on current energy prices, geothermal heat pump systems using mine water could reduce the annual costs for heating to over 70 percent compared to conventional heating methods (natural gas or heating oil). These same systems could reduce annual cooling costs by up to 50 percent over standard air conditioning in many areas of the country. (Formatted full-text version is released by permission of publisher)
Date: April 1, 2007
Creator: Watzlaf, George R. & Ackman, Terry E.
System: The UNT Digital Library
High Performance Piezoelectric Actuated Gimbal (HIERAX) (open access)

High Performance Piezoelectric Actuated Gimbal (HIERAX)

This paper presents a 3-axis gimbal whose three rotational axes are actuated by a novel drive system: linear piezoelectric motors whose linear output is converted to rotation by using drive disks. Advantages of this technology are: fast response, high accelerations, dither-free actuation and backlash-free positioning. The gimbal was developed to house a laser range finder for the purpose of tracking and guiding unmanned aerial vehicles during landing maneuvers. The tilt axis was built and the test results indicate excellent performance that meets design specifications.
Date: April 1, 2007
Creator: Tschaggeny, Charles; Jones, Warren & Bamberg, Eberhard
System: The UNT Digital Library
Ice damage in loblolly pine: Understanding the factors that influence susceptibility. (open access)

Ice damage in loblolly pine: Understanding the factors that influence susceptibility.

Abstract: Winter ice storms frequently occur in the southeastern United States and can severely damage softwood plantations. In January 2004, a severe storm deposited approximately 2 cm of ice on an intensively managed 4-year-old loblolly pine (Pinus taeda L.) plantation in South Carolina. Existing irrigation and fertilization treatments presented an opportunity to examine the effects of resource amendments on initial ice damage and subsequent recovery. Fertilized treatments showed more individual stem breakage, whereas non fertilized treatments showed more stem bending; however, the proportion of undamaged trees did not differ between treatments. Irrigation did not influence the type of damage. Trees that experienced breakage during the storm were taller with larger diameter and taper and leaf, branch, and crown biomass compared with unbroken trees. One growing season after ice damage, relative height increases were significantly greater for trees experiencing stem breakage compared with unbroken trees; however, relative diameter increases were significantly lower for these trees. Relative diameter increases for broken trees were smaller for fertilized treatments compared with nonfertilized treatments. A reduction in wood strength was ruled out as the cause of greater breakage in fertilized trees; rather, fertilized trees had reached an intermediate diameter range known to be susceptible to …
Date: April 1, 2007
Creator: Aubrey, Doug, P.; Coleman, Mark, D. & Coyle, David, R.
System: The UNT Digital Library