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Showing papers in "Lawrence Berkeley National Laboratory in 2006"


Journal Article
TL;DR: The benzene quasiparticle energy gap is predicted to be 7.2 eV on graphite, substantially reduced from its calculated gas-phase value of 10.5 eV, an effect completely absent from the corresponding Kohn-Sham gap.
Abstract: The electronic structure of benzene on graphite (0001) is computed using the $GW$ approximation for the electron self-energy. The benzene quasiparticle energy gap is predicted to be 7.2 eV on graphite, substantially reduced from its calculated gas-phase value of 10.5 eV. This decrease is caused by a change in electronic correlation energy, an effect completely absent from the corresponding Kohn-Sham gap. For weakly coupled molecules, this correlation energy change can be described as a surface polarization effect. A classical image potential model illustrates the impact for other conjugated molecules on graphite.

553 citations


Journal Article
TL;DR: Pruess et al. as discussed by the authors evaluated thermophysical properties and performed numerical simulations to explore the fluid dynamics and heat transfer issues in an engineered geothermal reservoir that would be operated with CO 2.
Abstract: Submitted to Geothermics, June 2006 LBNL-60397 Enhanced Geothermal Systems (EGS) Using CO 2 as Working Fluid – A Novel Approach for Generating Renewable Energy with Simultaneous Sequestration of Carbon Karsten Pruess Earth Sciences Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720 K_Pruess@lbl.gov Abstract Responding to the need to reduce atmospheric emissions of carbon dioxide, Donald Brown (2000) proposed a novel enhanced geothermal systems (EGS) concept that would use CO 2 instead of water as heat transmission fluid, and would achieve geologic sequestration of CO 2 as an ancillary benefit. Following up on his suggestion, we have evaluated thermophysical properties and performed numerical simulations to explore the fluid dynamics and heat transfer issues in an engineered geothermal reservoir that would be operated with CO 2 . We find that CO 2 is superior to water in its ability to mine heat from hot fractured rock. CO 2 also has certain advantages with respect to wellbore hydraulics, where larger compressibility and expansivity as compared to water would increase buoyancy forces and would reduce the parasitic power consumption of the fluid circulation system. While the thermal and hydraulic aspects of a CO 2 - EGS system look promising, major uncertainties remain with regard to chemical interactions between fluids and rocks. An EGS system running on CO 2 has sufficiently attractive features to warrant further investigation.

482 citations


Journal Article
TL;DR: It is reported that 22 of 129 individuals with Noonan syndrome without PTPN11 or KRAS mutation have missense mutations in SOS1, which encodes a RAS-specific guanine nucleotide exchange factor, and this finding defines a new mechanism by which upregulation of the RAS pathway can profoundly change human development.
Abstract: Noonan syndrome (NS) is a developmental disorder characterized by short stature, facial dysmorphia, congenital heart defects and skeletal anomalies1. Increased RAS-mitogenactivated protein kinase (MAPK) signaling due to PTPN11 and KRAS mutations cause 50 percent of NS2-6. Here, we report that 22 of 129 NS patients without PTPN11 or KRAS mutation (17 percent) have missense mutations in SOS1, which encodes a RAS-specific guanine nucleotide exchange factor (GEF). SOS1 mutations cluster at residues implicated in the maintenance of SOS1 in its autoinhibited form and ectopic expression of two NS-associated mutants induced enhanced RAS activation. The phenotype associated with SOS1 defects is distinctive, although within NS spectrum, with a high prevalence of ectodermal abnormalities but generally normal development and linear growth. Our findings implicate for the first time gain-of-function mutations in a RAS GEF in inherited disease and define a new mechanism by which upregulation of the RAS pathway can profoundly change human development.

455 citations


Journal Article
TL;DR: In this paper, the authors use coupled fluid flow and geomechanical fault slip analysis to estimate the maximum sustainable injection pressure during geological sequestration of CO2, and they conclude that a fully coupled numerical analysis can more accurately account for the spatial evolution of both in situ stresses and fluid pressure, and therefore results in a more accurate estimation of the CO2 injection pressure.
Abstract: This paper demonstrates the use of coupled fluid flow and geomechanical fault slip (fault reactivation) analysis to estimate the maximum sustainable injection pressure during geological sequestration of CO2. Two numerical modeling approaches for analyzing faultslip are applied, one using continuum stress-strain analysis and the other using discrete fault analysis. The results of these two approaches to numerical fault-slip analyses are compared to the results of a more conventional analytical fault-slip analysis that assumes simplified reservoir geometry. It is shown that the simplified analytical fault-slip analysis may lead to either overestimation or underestimation of the maximum sustainable injection pressure because it cannot resolve important geometrical factors associated with the injection induced spatial evolution of fluid pressure and stress. We conclude that a fully coupled numerical analysis can more accurately account for the spatial evolution of both in situ stresses and fluid pressure, and therefore results in a more accurate estimation of the maximum sustainable CO2 injection pressure.

357 citations


Journal Article
TL;DR: Karpen et al. as discussed by the authors showed that overexpressed CID is mislocalized into normally non-centromeric regions in Drosophila tissue culture cells and animals, and showed that mitotic delays, anaphase bridges, chromosome fragmentation, and cell and organismal lethality are all direct consequences of mislocalization.
Abstract: Editorial Manager(tm) for Developmental Cell Manuscript Draft Manuscript Number: DC-D-06-00013R1 Title: Mislocalization of the Drosophila centromere-specific histone CID promotes formation of functional ectopic kinetochores Article Type: Research Article Section/Category: Keywords: centromere CID CENP-A kinetochore mitosis aneuploidy Corresponding Author: Dr. Gary H. Karpen, Corresponding Author's Institution: Lawrence Berkeley National Lab/UC Berkeley First Author: Patrick Heun, PhD Order of Authors: Patrick Heun, PhD; Sylvia Erhardt, PhD; Michael D Blower, PhD; Samara Weiss, BA; Andrew D Skora, BA; Gary H Karpen, PhD Manuscript Region of Origin: Abstract: The centromere-specific histone variant CENP-A (CID in Drosophila) is a structural and functional foundation for kinetochore formation and chromosome segregation. Here, we show that overexpressed CID is mislocalized into normally non-centromeric regions in Drosophila tissue culture cells and animals. Analysis of mitoses in living and fixed cells reveals that mitotic delays, anaphase bridges, chromosome fragmentation, and cell and organismal lethality are all direct consequences of CID mislocalization. In addition, proteins that are normally restricted to endogenous kinetochores assemble at a subset of ectopic

317 citations


Journal Article
TL;DR: In this paper, the conceptual basis for how erosion can constitute a C sink is clarified, and it is shown that erosion and deposition can make a net positive contribution to C sequestration.
Abstract: Estimating carbon (C) balance in erosional and depositional landscapes is complicated by the effects of soil redistribution on both net primary productivity (NPP) and decomposition. Recent studies are contradictory as to whether soil erosion does or does not constitute a C sink. Here we clarify the conceptual basis for how erosion can constitute a C sink. Specifically, the criterion for an erosional C sink is that dynamic replacement of eroded C, and reduced decomposition rates in depositional sites, must together more than compensate for erosional losses. This criterion is in fact met in many erosional settings, and thus erosion and deposition can make a net positive contribution to C sequestration. We show that, in a cultivated Mississippi watershed and a coastal California watershed, the magnitude of the erosion-induced C sink is likely to be on the order of 1 percent of NPP and 16 percent of eroded C. Although soil erosion has serious environmental impacts, the annual erosion-induced C sink offsets up to 10 percent of the global fossil fuel emissions of carbon dioxide for 2005.

286 citations


Journal Article
TL;DR: Seppanen et al. as discussed by the authors investigated the effect of temperature on performance in office environment monitoring and found that it had a significant impact on the performance of the monitoring system.
Abstract: LBNL- 60946 EFFECT OF TEMPERATURE ON TASK PERFORMANCE IN OFFFICE ENVIRONMENT Olli Seppanen 1 , William J Fisk 2 , QH Lei 2 Helsinki University of Technology, Laboratory for Heating Ventilating and Air-conditioning, PO Box 4100, FIN-02015 HUT, Finland Lawrence Berkeley National Laboratory Environmental Energy Technologies Division Indoor Environment Department Berkeley, CA 94720 July 2006 This work was supported by the Finnish Academy. This work was also supported by the Indoor Environments Division, Office of Radiation and Indoor Air, Office of Air and Radiation of the U.S. Environmental Protection Agency through interagency agreement DW-89-92175001-0 with the U.S. Department of Energy.

239 citations


Journal Article
TL;DR: Seppanen et al. as discussed by the authors investigated the relationship between indoor environment quality and work performance and found that the former is more conducive to the latter than the former, with the assistance of the Academy of Finland and U.S. Department of Energy.
Abstract: LBNL-59876 SOME QUANTITATIVE RELATIONS BETWEEN INDOOR ENVIRONMENTAL QUALITY AND WORK PERFORMANCE OR HEALTH Olli A Seppanen 1 , William J Fisk 2 Helsinki University of Technology Finland Lawrence Berkeley National Laboratory Environmental Energy Technology Division Indoor Environment Department Berkeley, CA 94720 February 2006 This work was supported by the Academy of Finland. This work was also supported by the Indoor Environments Division, Office of Radiation and Indoor Air, Office of Air and Radiation of the U.S. Environmental Protection Agency through interagency agreement DW- 89-92175001-0 with the U.S. Department of Energy. This work was also supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Building Technology of the U.S. Department of Energy under contract DE-AC03-76SF00098.

238 citations


Journal Article
TL;DR: A metagenomic approach is used to describe four co-occurring symbionts from the marine oligochaete Olavius algarvensis, a worm lacking a mouth, gut and nephridia to propose a model that describes how the versatile metabolism within this symbiotic consortium provides the host with an optimal energy supply as it shuttles between the upper oxic and lower anoxic coastal sediments that it inhabits.
Abstract: Symbiosis insights through metagenomic analysis of a microbial consortium Tanja Woyke 1,2 , Hanno Teeling 3 , Natalia N. Ivanova 1 , Marcel Hunteman 3 , Michael Richter 3 , Frank Oliver Gloeckner 3,4 , Dario Boffelli 1,2 , Iain J. Anderson 1 , Kerrie W. Barry 1 , Harris J. Shapiro 1 , Ernest Szeto 1 , Nikos C. Kyrpides 1 , Marc Mussmann 3 , Rudolf Amann 3 , Claudia Bergin 3 , Caroline Ruehland 3 , Edward M. Rubin 1,2,† & Nicole Dubilier 3,† DOE Joint Genome Institute, Walnut Creek, California 94598, USA. Lawrence Berkeley National Laboratory, Genomics Division, Berkeley, California 94720, USA. Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany. International University Bremen, 28759 Bremen, Germany. † Correspondence should be addressed to: N. D. (ndubilie@mpi-bremen.de) and E. M. R. (EMRubin@lbl.gov).

170 citations


Journal Article
TL;DR: Maeder et al. as discussed by the authors compared the Methanosarcina barkeri genome with methanearcina mazei and showed extensive rearrangement within methanosarcinal genomes.
Abstract: LBNL-60247 Preprint Title: The Methanosarcina barkeri genome: comparative analysis with Methanosarcina acetivorans and Methanosarcina mazei reveals extensive rearrangement within methanosarcinal genomes Author(s): Dennis L. Maeder, Iain Anderson, et al Division: Genomics November 2006 Journal of Bacteriology

153 citations


Journal Article
TL;DR: The results presented here clearly demonstrate the differences between the two biovar antiqua lineages and support the notion that grouping Y. pestis strains based strictly on the classical definition of biovars does not accurately reflect the phylogenetic relationships within this species.
Abstract: Yersinia pestis, the causative agent of bubonic and pneumonic plague, has undergone detailed study at the molecular level. To further investigate the genomic diversity among this group and to help characterize lineages of the plague organism that have no sequenced members, we present here the genomes of two isolates of the classical Antiqua biovar, strains Antiqua and Nepal516. The genomes of Antiqua and Nepal516 are 4.7 Mb and 4.5 Mb and encode 4,138 and 3,956 open reading frames respectively. Though both strains belong to one of the three classical biovars, they represent separate lineages defined by recent phylogenetic studies. We compare all five currently sequenced Y. pestis genomes and the corresponding features in Y. pseudotuberculosis. There are strain-specific rearrangements, insertions, deletions, single nucleotide polymorphisms and a unique distribution of insertion sequences. We found 453 single nucleotide polymorphisms in protein coding regions, which were used to assess evolutionary relationships of these Y. pestis strains. Gene reduction analysis revealed that the gene deletion processes are under selective pressure and many of the inactivations are probably related to the organism s interaction with its host environment. The results presented here clearly demonstrate the differences between the two Antiqua lineages and support the notion that grouping Y. pestis strains based strictly on the classical definition of biovars (predicated upon two biochemical assays) does not accurately reflect the phylogenetic relationships within this species. Comparison of four virulent Y. pestis strains with the human-avirulent strain 91001 provides further insight into the genetic basis of virulence to humans.

Journal Article
TL;DR: In this paper, the scaling relations for the critical current density (Jc) in Nb3Sn wires and include recent findings on the variation of the upper critical field (Hc2) with temperature (T) and A15 composition.
Abstract: We review the scaling relations for the critical current density (Jc) in Nb3Sn wires and include recent findings on the variation of the upper critical field (Hc2) with temperature (T) and A15 composition. Measurements of Hc2(T) in inevitably inhomogeneous wires, as well as analysis of literature results, have shown that all available Hc2(T) data can be accurately described by a single relation from the microscopic theory. This relation also holds for inhomogeneity averaged, effective, Hc2*(T) results and can be approximated by Hc2(t)=Hc2(0) = 1-t1.52, with t = T=Tc.Knowing Hc2*(T) implies that also Jc(T) is known. We highlight deficiencies in the Summers/Ekin relations, which are not able to account for the correct Jc(T) dependence. Available Jc(H) results indicate that the magnetic field dependence for all wires from mu0H = 1 T up to about 80 percent of the maximum Hc2 can be described with Kramer's flux shear model, if non-linearities in Kramer plots when approaching the maximum Hc2 are attributed to A15 inhomogeneities. The strain (e) dependence is introduced through a temperature and strain dependent Hc2*(T,e) and Ginzburg-Landau parameter kappa1(T,e) and a strain dependent critical temperature Tc(e). This is more consistent than the usual Ekin unification of strain and temperature dependence, which uses two separate and different dependencies on Hc2*(T) and Hc2*(e). Using a correct temperature dependence and accounting for the A15 inhomogeneities leads to the remarkable simple relation Jc(H,T,e)= (C/mu0H)s(e)(1-t1.52)(1-t2)h0.5(1-h)2, where C is a constant, s(e) represents the normalized strain dependence of Hc2*(0) andh = H/Hc2*(T,e). Finally, a new relation for s(e) is proposed, which is an asymmetric version of our earlier deviatoric strain model and based on the first, second and third strain invariants. The new scaling relation solves a number of much debated issues withrespect to Jc scaling in Nb3Sn and is therefore of importance to the applied community, who use scaling relations to analyze magnet performance from wire results.

Journal Article
TL;DR: It is shown that the opportunistic pathogen Pseudomonas aeruginosa forms biofilms within 8 h of infection in thermally injured mice, demonstrating that biofilmms contribute to bacterial colonization in acute infections as well.
Abstract: Pseudomonas aeruginosa forms Biofilms in Acute Infection Independent of Cell-to- Cell Signaling J. Andy Schaber 1, 2 , Jeff Triffo 3 , Sang Jin Suh 4 , Jeffrey W. Oliver 5 , Mary Catherine Hastert 6 , John A. Griswold 1 , Manfred Auer 3 , Abdul N. Hamood 2 , Kendra P. Rumbaugh 1, Departments of Surgery 1 , Microbiology and Immunology 2 Pathology 5 , and Cell Biology and Biochemistry 6 Texas Tech University Health Sciences Center, 3601 4 th St., Lubbock, Texas, 79430, USA; Life Sciences Division, Lawrence Berkley National Laboratory, Berkley, California, 94720 3 ; Department of Biological Sciences, Auburn University, Auburn, Alabama, 36849 4 Corresponding author: Kendra Rumbaugh, Ph.D. Texas Tech University Health Sciences Center Department of Surgery 3601 4 th Street Lubbock, Texas 79430 phone: 806-743-2460, ext. 264 fax: 806-743-2370 e-mail: kendra.rumbaugh@ttuhsc.edu

Journal Article
TL;DR: In this article, the authors evaluate the Joule-Thomson cooling effect during CO2 injection into depleted natural gas reservoirs and show that for typical systems in the Sacramento Valley, California, the effect is minimal.
Abstract: Depleted natural gas reservoirs are a promising target for Carbon Sequestration with Enhanced Gas Recovery (CSEGR). The focus of this study is on evaluating the importance of Joule-Thomson cooling during CO2 injection into depleted natural gas reservoirs. Joule-Thomson cooling is the adiabatic cooling that accompanies the expansion of a real gas. If Joule-Thomson cooling were extreme, injectivity and formation permeability could be altered by the freezing of residual water, formation of hydrates, and fracturing due to thermal stresses. The TOUGH2/EOS7C module for CO2-CH4-H2O mixtures is used as the simulation analysis tool. For verification of EOS7C, the classic Joule-Thomson expansion experiment is modeled for pure CO2 resulting in Joule-Thomson coefficients in agreement with standard references to within 5-7 percent. For demonstration purposes, CO2 injection at constant pressure and with a large pressure drop (~;50 bars) is presented in order to show that cooling by more than 20oC can occur by this effect. Two more-realistic constant-rate injection cases show that for typical systems in the Sacramento Valley, California, the Joule-Thomson cooling effect is minimal. This simulation study shows that for constant-rate injections into high-permeability reservoirs, the Joule-Thomson cooling effect is not expected to create significant problems for CSEGR.

Journal Article
TL;DR: In this paper, the authors compare the use of kinetic and equilibrium reaction models in the simulation of gas hydrate behavior in porous media and find that the calculated responses for both reaction models are remarkably similar, though some differences are observed at early times.
Abstract: In this study we compare the use of kinetic and equilibrium reaction models in the simulation of gas (methane) hydrate behavior in porous media. Our objective is to evaluate through numerical simulation the importance of employing kinetic versus equilibrium reaction models for predicting the response of hydrate-bearing systems to external stimuli, such as changes in pressure and temperature. Specifically, we (1) analyze and compare the responses simulated using both reaction models for natural gas production from hydrates in various settings and for the case of depressurization in a hydrate-bearing core during extraction; and (2) examine the sensitivity to factors such as initial hydrate saturation, hydrate reaction surface area, and numerical discretization. We find that for large-scale systems undergoing thermal stimulation and depressurization, the calculated responses for both reaction models are remarkably similar, though some differences are observed at early times. However, for modeling short-term processes, such as the rapid recovery of a hydrate-bearing core, kinetic limitations can be important, and neglecting them may lead to significant under-prediction of recoverable hydrate. The use of the equilibrium reaction model often appears to be justified and preferred for simulating the behavior of gas hydrates, given that the computational demands for the kinetic reaction model far exceed those for the equilibrium reaction model.

Journal Article
TL;DR: In this paper, the authors developed a bottom-up approach for assessing the cost to U.S. electricity consumers of power interruptions and power quality events (referred to collectively as reliability events).
Abstract: The massive electric power blackout in the northeastern U.S. and Canada on August 14-15, 2003 catalyzed discussions about modernizing the U.S. electricity grid. Industry sources suggested that investments of $50 to $100 billion would be needed. This work seeks to better understand an important piece of information that has been missing from these discussions: What do power interruptions and fluctuations in power quality (power-quality events) cost electricity consumers? We developed a bottom-up approach for assessing the cost to U.S. electricity consumers of power interruptions and power-quality events (referred to collectively as reliability events ). The approach can be used to help assess the potential benefits of investments in improving the reliability of the grid. We developed a new estimate based on publicly available information, and assessed how uncertainties in these data affect this estimate using sensitivity analysis.

Journal Article
TL;DR: A variation of the F-test for determining statistical relevance of particular parameters in EXAFS data has been proposed in this paper, which has been shown to be useful for determining whether a particular scattering shell is warranted, and differentiating between two possible species or two possible structures.
Abstract: A Variation of the F-test for Determining Statistical Relevance of Particular Parameters in EXAFS Fits L. Downward ∗,† , C. H. Booth † , W. W. Lukens † and F. Bridges ∗ Physics Department, University of California, Santa Cruz, California 95060, USA Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Abstract. A general problem when fitting EXAFS data is determining whether particular parameters are statistically significant. The F-test is an excellent way of determining relevancy in EXAFS because it only relies on the ratio of the fit residual of two possible models, and therefore the data errors approximately cancel. Although this test is widely used in crystallography (there, it is often called a “Hamilton test”) and has been properly applied to EXAFS data in the past, it is very rarely applied in EXAFS analysis. We have implemented a variation of the F-test adapted for EXAFS data analysis in the RSXAP analysis package, and demonstrate its applicability with a few examples, including determining whether a particular scattering shell is warranted, and differentiating between two possible species or two possible structures in a given shell. Keywords: EXAFS, F-Test, Hamilton Test PACS: 07.05.Kf, 61.10.Ht 1. INTRODUCTION When fitting EXAFS data, one often must decide whether adding parameters or otherwise changing the fitting model significantly improves the fit beyond simply comparing the goodness-of-fit parameters. Hamilton[1] proposed a method based on the statistical F-test which has been widely used by crystallographers and has been extended by Bacchi et. al.[2]. Although many authors[3–7] have previously utilized the F-test with EXAFS data and have noted the importance of such a statistical test, it is still rarely applied. A number of possible scenarios can arise in EXAFS analysis where the F-test should be applied. In fitting data to theoretical standards, the parameters usually come in groups associated with scattering shells; in general there are at least three or more new parameters per shell, though often some are constrained. A common question when fitting EXAFS data is to ask whether adding an- other shell (which often includes the addition of multiple parameters) would significantly improve the fit. Alterna- tively, one might ask whether one of the included shells could be removed without significantly worsening the fit. Other scenarios include using additional parameters for a given scattering shell, such as a third cumulant[8], or comparing different fitting models. Here we begin by describing the F-test, focusing on the methodology of Hamilton. We then give examples of its application on (1) a system where one determines the significance of an additional scattering shell, and (2) where one questions the local structure of a given shell. 2. METHOD The F-test is generally used in statistics to determine if the standard deviations of two populations are equal. Equivalently, F = (where χ 0 represents the statistical χ 2 of the better fit 2 F exp gives the significance level at which the null hy- pothesis (that the two fits are not significantly different) can be rejected. A small value implies a very significant rejection in turn implying high confidence in the hypoth- esis that the fit that yields χ 0 is significantly better fit than 2 . In this paper, we report α (Eqn. 6) the fit that yields χ 1 as the confidence level that the χ 0 fit is the correct fit. Equation 1 gives the general formula for the F-Test in statistics. In EXAFS analysis, however, it is generally preferable to test the variation of χ 2 versus the best fit (See Eqn. 2) in order to account for the possibility that some of the parameters in the two fits may be the same. F = Though one can immediately see that this equation cannot be applied when ν 0 = ν 1 , i.e. when the number of fit parameters are the same in the two fits. In that case, July 9, 2006 A Variation of the F-Test in EXAFS Fits

ReportDOI
TL;DR: In this paper, Price et al. studied the trends in Global Energy Use and Greenhouse Gas Emissions and showed that the global energy use and greenhouse gas emissions are correlated with the number of people living in the United States.
Abstract: LBNL-56144 Sectoral Trends in Global Energy Use and Greenhouse Gas Emissions Lynn Price, Stephane de la Rue du Can, Jonathan Sinton, Ernst Worrell, Zhou Nan, Jayant Sathaye and Mark Levine Energy Analysis Department Environmental Energy Technologies Division Lawrence Berkeley National Laboratory July 2006 This work was supported by Laboratory Directed Research and Development funds under the U.S. Department of Energy Contract No. DE-AC02-05CH11231.

Journal Article
TL;DR: Performance at office work shows that performance increases with temperature up to 21-22 C, and decreases with temperature above 23-24 C, while the highest productivity is at temperature of around 22 C.
Abstract: Indoor temperature is one of the fundamental characteristics of the indoor environment It can be controlled with a degree of accuracy dependent on the building and its HVAC system The indoor temperature affects several human responses, including thermal comfort, perceived air quality, sick building syndrome symptoms and performance at work In this study, we focused on the effects of temperature on performance at office work We included those studies that had used objective indicators of performance that are likely to be relevant in office type work, such as text processing, simple calculations (addition, multiplication), length of telephone customer service time, and total handling time per customer for call-center workers We excluded data from studies of industrial work performance We calculated from all studies the percentage of performance change per degree increase in temperature, and statistically analyzed measured work performance with temperature The results show that performance increases with temperature up to 21-22 C, and decreases with temperature above 23-24 C The highest productivity is at temperature of around 22 C For example, at the temperature of 30 C, the performance is only 911% of the maximum ie the reduction in performance is 89%

Journal Article
TL;DR: In contrast to traditional gene-centric studies in which investigators randomly scanned genomic fragments that flank genes of interest in functional assays, the modern approach begins electronically with publicly available comparative sequence datasets that provide investigators with prioritized lists of putative functional sequences based on their evolutionary conservation.
Abstract: With the availability of genomic sequence from numerous vertebrates, a paradigm shift has occurred in the identification of distant-acting gene regulatory elements. In contrast to traditional gene-centric studies in which investigators randomly scanned genomic fragments that flank genes of interest in functional assays, the modern approach begins electronically with publicly available comparative sequence datasets that provide investigators with prioritized lists of putative functional sequences based on their evolutionary conservation. However, although a large number of tools and resources are now available, application of comparative genomic approaches remains far from trivial. In particular, it requires users to dynamically consider the species and methods for comparison depending on the specific biological question under investigation. While there is currently no single general rule to this end, it is clear that when applied appropriately, comparative genomic approaches exponentially increase our power in generating biological hypotheses for subsequent experimental testing.

ReportDOI
TL;DR: Arnold Schwarzenegger Governor ADVANCEMENT of ELECTROCHROMIC WINDOWS Prepared For: California Energy Commission Public Interest Energy Research Program Prepared By: Lawrence Berkeley National Laboratory April 2006 CEC-500-2006-052 PIER F INAL P ROJECT R EPORT
Abstract: Arnold Schwarzenegger Governor ADVANCEMENT OF ELECTROCHROMIC WINDOWS Prepared For: California Energy Commission Public Interest Energy Research Program Prepared By: Lawrence Berkeley National Laboratory April 2006 CEC-500-2006-052 PIER F INAL P ROJECT R EPORT

Journal Article
TL;DR: In this article, the elastic properties and electronic structure of PtN2 with the pyrite structure (PtN2(C2)) were studied with first-principles calculations.
Abstract: The elastic properties and electronic structure of PtN2 with the pyrite structure (PtN2(C2)) were studied with first-principles calculations. The crystal structure is demonstrated to be elastically stable with a lower energy than the metastable fluorite structure proposed before. The calculated shear modulus of 214 GPa suggests that PtN2(C2) is harder than some well known hard materials such as TiN and SiC. The high elastic moduli are attributed to a stacking of corner-shared PtN6 octahedra bonded by strong N-N covalent bonding. In contrast to the metallic fluorite-type phase, PtN2(C2) is semiconducting with an indirect band gap.

ReportDOI
TL;DR: In this article, the authors investigate the magnitude of the principal-agent (PA) problem affecting four of the major energy end uses in the U.S. residential sector: refrigeration, water heating, space heating, and lighting.
Abstract: The International Energy Agency (IEA) initiated andcoordinated this project to investigate the effects of market failures inthe end-use of energy that may isolate some markets or portions thereoffrom energy price signals in five member countries. Quantifying theamount of energy associated with market failures helps to demonstrate thesignificance of energy efficiency policies beyond price signals. In thisreport we investigate the magnitude of the principal-agent (PA) problemaffecting four of the major energy end uses in the U.S. residentialsector: refrigeration, water heating, space heating, and lighting. Usingdata from the American Housing Survey, we develop a novel approach toclassifying households into a PA matrix for each end use. End use energyvalues differentiated by housing unit type from the Residential EnergyConsumption Survey were used to estimate the final and primary energy useassociated with the PA problem. We find that the 2003 associated siteenergy use from these four end uses totaled over 3,400 trillion Btu,equal to 35 percent of the site energy consumed by the residentialsector.

Reference BookDOI
TL;DR: In this paper, the authors provide an overview of the use of ultrafast terahertz (THz) time-domain spectroscopy to study light-matter interactions and microscopic processes in nanoscale and correlated-electron materials.
Abstract: Perhaps the most important aspect of contemporary condensed matter physics involves understanding strong Coulomb interactions between the large number of electrons in a solid. Electronic correlations lead to the emergence of new system properties, such as metal-insulator transitions, superconductivity, magneto-resistance, Bose-Einstein condensation, the formation of excitonic gases, or the integer and fractional Quantum Hall effects. The discovery of high-Tc superconductivity in particular was a watershed event, leading to dramatic experimental and theoretical advances in the field of correlated-electron systems. Such materials often exhibit competition between the charge, lattice, spin, and orbital degrees of freedom, whose cause-effect relationships are difficult to ascertain. Experimental insight into the properties of solids is traditionally obtained by time-averaged probes, which measure e.g., linear optical spectra, electrical conduction properties, or the occupied band structure in thermal equilibrium. Many novel physical properties arise from excitations out of the ground state into energetically higher states by thermal, optical, or electrical means. This leads to fundamental interactions between the system's constituents, such as electron-phonon and electron-electron interactions, which occur on ultrafast timescales. While these interactions underlie the physical properties of solids, they are often only indirectly inferred from time-averaged measurements. Time-resolved spectroscopy, consequently, is playing an ever increasing rolemore » to provide insight into light-matter interaction, microscopic processes, or cause-effect relationships that determine the physics of complex materials. In the past, experiments using visible and near-infrared femtosecond pulses have been extensively employed, e.g. to follow relaxation and dephasing processes in metals and semiconductors. However, many basic excitations in strongly-correlated electron systems and nanoscale materials occur at lower energies. The terahertz (THz) regime is particularly rich in such fundamental resonances. This includes ubiquitous lattice vibrations and low-energy collective oscillations of conduction charges. In nanoscale materials, band structure quantization also yields novel infrared and THz transitions, including intersubband absorption in quantum wells. The formation of excitons in turn leads to low-energy excitations analogous to inter-level transitions in atoms. In transition-metal oxides, fundamental excitation gaps arise from charge pairing into superconducting condensates and other correlated states. This motivates the use of ultrafast THz spectroscopy as a powerful tool to study light-matter interactions and microscopic processes in nanoscale and correlated-electron materials.A distinct advantage of coherent THz pulses is that the amplitude and phase of the electric field can be measured directly, as the THz fields are coherent with the fs pulses from which they are generated. Using THz time-domain spectroscopy (THz-TDS), both the real and imaginary parts of the response functions (such as the dielectric function) are obtained directly without the need for Kramers?Kronig transforms. The THz response can also be expressed in terms of absorption and refractive index, or as the optical conductivity. The optical conductivity describes the current response of a many-body system to an electric field, an ideal tool to study conducting systems. A second important advantage is the ultrafast time resolution that results from the short temporal duration of the THz time-domain sources. In particular, optical-pump THz-probe spectroscopy enables a delicate probe of the transient THz conductivity after optical photoexcitation. These experiments can provide insight into quasiparticle interactions, phase transitions, or nonequilibrium dynamics. In this chapter we will provide many such examples. Since THz spectroscopy of solids is a quickly expanding field« less

Journal Article
TL;DR: It is shown here that extracellular matrix molecules and prolactin cooperate to induce histone acetylation and binding of transcription factors and the SWI/SNF complex to the β- and γ-casein promoters.
Abstract: EXTRACELLULAR MATRIX-REGULATED GENE EXPRESSION REQUIRES COOPERATION OF SWI/SNF AND TRANSCRIPTION FACTORS Ren Xu, Virginia A Spencer, Mina J. Bissell From Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, MS 977R225A, Berkeley, CA 94720, USA Running Title: SWI/SNF Regulates Casein Expression Address correspondence to Mina J Bissell, Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, MS 977R225A, Berkeley, CA 94720, USA. Tel: 510 486-4365; Fax: 510 486-5586; Email: MJBissell@lbl.gov Key Words: extracellular matrix, chromatin remodeling, SWI/SNF, histone acetylation. Extracellular cues play crucial roles in the transcriptional regulation of tissue-specific genes, but whether and how these signals lead to chromatin remodeling is not understood and subject to debate. Using chromatin immunoprecipitation (ChIP) assays and mammary-specific genes as models, we show here that extracellular matrix (ECM) molecules and prolactin cooperate to induce histone acetylation and binding of transcription factors and the SWI/SNF complex to the s- and ?-casein promoters. Introduction of a dominant negative Brg1, an ATPase subunit of SWI/SNF complex, significantly reduced both s- and ?-casein expression, suggesting that SWI/SNF-dependent chromatin remodeling is required for transcription of mammary-specific genes. ChIP analyses demonstrated that the ATPase activity of SWI/SNF is necessary for recruitment of RNA transcriptional machinery, but not for binding of transcription factors or for histone acetylation. Co- immunoprecipitation analyses showed that the SWI/SNF complex is associated with STAT5, C/EBPs, and glucocorticoid receptor (GR). Thus, ECM- and prolactin- regulated transcription of the mammary- specific casein genes requires the concerted action of chromatin remodeling enzymes and transcription factors. Differentiated function of mammary epithelial cells is regulated by signals from both ECM and lactogenic hormones (1-3). The gene encoding the milk protein, s-casein, has been used widely as a marker for functional differentiation of MECs. We and others have shown that in both primary mouse mammary epithelial cells and immortalized mammary epithelial cell lines (4-6), transcription of s- casein requires signals from both laminin-111 (previously referred to as laminin-1) and prolactin (1,2,7-10). A number of transcription factors, including STAT5, C/EBPs, and GR, have been shown to be involved in this process [reviewed in (7)]. Modulation of chromatin structure by histone modifications and ATP-dependent remodeling has been implicated in cell differentiation and transcriptional control of tissue-specific and inducible genes (11-13). Histone modifying enzymes are believed to be recruited to promoter regions through their association with transcription factors, and are critical for tissue-specific gene expression and functional differentiation of specific cell types (14,15). Histone acetylation is a dynamic process and is regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs) (16). The mapping of global histone acetylation patterns has demonstrated that chromatin accessibility and gene expression are correlated with histone hyperacetylation of

ReportDOI
TL;DR: In this paper, Piette et al. presented an automated critical peak pricing field test at the Lawrence Berkeley National Laboratory (LBNL) sponsored by the Pacific Gas and Electric Company Emerging Technologies Program.
Abstract: Automated Critical Peak Pricing Field Tests: Program Description and Results April 6, 2006 Mary Ann Piette David Watson Naoya Motegi Sila Kiliccote Peng Xu Lawrence Berkeley National Laboratory Sponsored by the Pacific Gas and Electric Company Emerging Technologies Program California Institute for Energy and the Environment LBNL Report Number 59351

Journal Article
TL;DR: Alykidis et al. as discussed by the authors utilized comparative genomics and phylogenetics for exploring the distribution, structure and evolution of phospholipid biosynthetic genes and pathways in 26 eukaryotic genomes.
Abstract: Comparative genomics and evolution of eukaryotic phospholipid biosynthesis Athanasios Lykidis Genome Biology Program, DOE-Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598, U.S.A. Tel: 925-2965842; Fax: 925-2965850; Email: alykidis@lbl.gov Abstract Phospholipid biosynthetic enzymes produce diverse molecular structures and are often present in multiple forms encoded by different genes. This work utilizes comparative genomics and phylogenetics for exploring the distribution, structure and evolution of phospholipid biosynthetic genes and pathways in 26 eukaryotic genomes. Although the basic structure of the pathways was formed early in eukaryotic evolution, the emerging picture indicates that individual enzyme families followed unique evolutionary courses. For example, choline and ethanolamine kinases and cytidylyltransferases emerged in ancestral eukaryotes, whereas, multiple forms of the corresponding phosphatidyltransferases evolved mainly in a lineage specific manner. Furthermore, several unicellular eukaryotes maintain bacterial-type enzymes and reactions for the synthesis of phosphatidylglycerol and cardiolipin. Also, base-exchange phosphatidylserine synthases are widespread and ancestral enzymes. The multiplicity of phospholipid biosynthetic enzymes has been largely generated by gene expansion in a lineage specific manner. Thus, these observations suggest that phospholipid biosynthesis has been an actively evolving system.

Journal Article
TL;DR: Kiliccote et al. as mentioned in this paper presented at the Second Carnegie Mellon Conference in Electric Power Systems: Monitoring, Sensing, Software and Its Valuation for the Changing Electric Power Industry, January 12, 2006, Pittsburgh, PA.
Abstract: LBNL-59337 Presented at Second Carnegie Mellon Conference in Electric Power Systems: Monitoring, Sensing, Software and Its Valuation for the Changing Electric Power Industry, January 12, 2006, Pittsburgh, PA. Advanced Controls and Communications for Demand Response and Energy Efficiency in Commercial Buildings Sila Kiliccote, Mary Ann Piette Lawrence Berkeley National Laboratory David Hansen U.S. Department of Energy This work was supported by the New York State Energy and Research Development Authority (NYSERDA) and the Demand Response Research Center (drrc.lbl.gov) funded by the California Energy Commission, Public Interest Energy Research Program, under Work for Others Contract No.150-99-003, Am #1 and by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

Journal Article
TL;DR: SAXS shape predictions for PCNA that accurately predict a trimeric ring assembly and for a full-length DNA repair glycosylase with a large unstructured region are presented and show how SAXS combined with high resolution crystal structures efficiently establishes architectures, assemblies, conformations, and unStructured regions for proteins and protein complexes in solution.
Abstract: Structural analysis of flexible proteins in solution by small angle X-ray scattering combined with crystallography Susan E. Tsutakawa 1 , Greg L. Hura 2 , Ken A. Frankel 3 , Priscilla K. Cooper 1 , and John A. Tainer 1,4 Life Science Division, 2 Physical Biosciences Division and 3 Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 The Scripps Research Institute, La Jolla, CA To whom correspondence should be addressed: John A. Tainer, Ph.D. Professor, Department of Molecular Biology and The Skaggs Institute for Chemical Biology The Scripps Research Institute 10550 North Torrey Pines Road Mailstop: MB4 La Jolla, CA 92037 phone: (858) 784-8119 fax: (858) 784-2289 e-mail: jat@scripps.edu

Journal Article
TL;DR: In this paper, a wide variety of targets, both elemental and composite, were placed in the particle beams, and the spectra of particles emerging from the targets were measured using a stack of silicon detectors.
Abstract: The design of future spacecraft such as the Crew Exploration Vehicle must take into account the radiation shielding properties of both the structural components as well as dedicated shielding materials. Since modest depths of shielding stop the vast majority of Solar Energetic Particles (SEP), the greater challenge is posed by the need to shield crew from the Galactic Cosmic Rays (GCR), which include highly-charged and highly-energetic particles. Here, we report on results from tests performed with beams of 1 GeV/nuc 56Fe at the Brookhaven National Laboratory. A wide variety of targets, both elemental and composite, were placed in the particle beams, and the spectra of particles emerging from the targets were measured using a stack of silicon detectors. Results are presented primarily in terms of dose reduction per g cm-2 of target material, and support the conclusions of an earlier calculation by Wilson et al. showing that performance improves as the shield's mass number decreases, with hydrogen being by far the most effective. The data also show that, as depth increases, the incremental benefit of adding shielding decreases, particularly for aluminum and other elements with higher atomic mass numbers.