Superconducting Magnets and Materials R&D | Technical Division

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Dipoles for VLHC The design and main parameters of FNAL dipole models of the HFDA series are described in structure suitable for industrialization. The magnet design was based on a two-layer shell-type coil and a design (HFDC), which meets the VLHC requirements and allows using the React&Wind (R&W) technology

FragFit: a web-application for interactive modeling of protein segments into cryo-EM density maps.

PubMed

Tiemann, Johanna K S; Rose, Alexander S; Ismer, Jochen; Darvish, Mitra D; Hilal, Tarek; Spahn, Christian M T; Hildebrand, Peter W

2018-05-21

Cryo-electron microscopy (cryo-EM) is a standard method to determine the three-dimensional structures of molecular complexes. However, easy to use tools for modeling of protein segments into cryo-EM maps are sparse. Here, we present the FragFit web-application, a web server for interactive modeling of segments of up to 35 amino acids length into cryo-EM density maps. The fragments are provided by a regularly updated database containing at the moment about 1 billion entries extracted from PDB structures and can be readily integrated into a protein structure. Fragments are selected based on geometric criteria, sequence similarity and fit into a given cryo-EM density map. Web-based molecular visualization with the NGL Viewer allows interactive selection of fragments. The FragFit web-application, accessible at http://proteinformatics.de/FragFit, is free and open to all users, without any login requirements.

Structure of the 30 kDa HIV-1 RNA Dimerization Signal by a Hybrid Cryo-EM, NMR, and Molecular Dynamics Approach.

PubMed

Zhang, Kaiming; Keane, Sarah C; Su, Zhaoming; Irobalieva, Rossitza N; Chen, Muyuan; Van, Verna; Sciandra, Carly A; Marchant, Jan; Heng, Xiao; Schmid, Michael F; Case, David A; Ludtke, Steven J; Summers, Michael F; Chiu, Wah

2018-03-06

Cryoelectron microscopy (cryo-EM) and nuclear magnetic resonance (NMR) spectroscopy are routinely used to determine structures of macromolecules with molecular weights over 65 and under 25 kDa, respectively. We combined these techniques to study a 30 kDa HIV-1 dimer initiation site RNA ([DIS] 2 ; 47 nt/strand). A 9 Å cryo-EM map clearly shows major groove features of the double helix and a right-handed superhelical twist. Simulated cryo-EM maps generated from time-averaged molecular dynamics trajectories (10 ns) exhibited levels of detail similar to those in the experimental maps, suggesting internal structural flexibility limits the cryo-EM resolution. Simultaneous inclusion of the cryo-EM map and 2 H-edited NMR-derived distance restraints during structure refinement generates a structure consistent with both datasets and supporting a flipped-out base within a conserved purine-rich bulge. Our findings demonstrate the power of combining global and local structural information from these techniques for structure determination of modest-sized RNAs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Single-particle cryo-EM using alignment by classification (ABC): the structure of Lumbricus terrestris haemoglobin.

PubMed

Afanasyev, Pavel; Seer-Linnemayr, Charlotte; Ravelli, Raimond B G; Matadeen, Rishi; De Carlo, Sacha; Alewijnse, Bart; Portugal, Rodrigo V; Pannu, Navraj S; Schatz, Michael; van Heel, Marin

2017-09-01

Single-particle cryogenic electron microscopy (cryo-EM) can now yield near-atomic resolution structures of biological complexes. However, the reference-based alignment algorithms commonly used in cryo-EM suffer from reference bias, limiting their applicability (also known as the 'Einstein from random noise' problem). Low-dose cryo-EM therefore requires robust and objective approaches to reveal the structural information contained in the extremely noisy data, especially when dealing with small structures. A reference-free pipeline is presented for obtaining near-atomic resolution three-dimensional reconstructions from heterogeneous ('four-dimensional') cryo-EM data sets. The methodologies integrated in this pipeline include a posteriori camera correction, movie-based full-data-set contrast transfer function determination, movie-alignment algorithms, (Fourier-space) multivariate statistical data compression and unsupervised classification, 'random-startup' three-dimensional reconstructions, four-dimensional structural refinements and Fourier shell correlation criteria for evaluating anisotropic resolution. The procedures exclusively use information emerging from the data set itself, without external 'starting models'. Euler-angle assignments are performed by angular reconstitution rather than by the inherently slower projection-matching approaches. The comprehensive 'ABC-4D' pipeline is based on the two-dimensional reference-free 'alignment by classification' (ABC) approach, where similar images in similar orientations are grouped by unsupervised classification. Some fundamental differences between X-ray crystallography versus single-particle cryo-EM data collection and data processing are discussed. The structure of the giant haemoglobin from Lumbricus terrestris at a global resolution of ∼3.8 Å is presented as an example of the use of the ABC-4D procedure.

PRISM-EM: template interface-based modelling of multi-protein complexes guided by cryo-electron microscopy density maps.

PubMed

Kuzu, Guray; Keskin, Ozlem; Nussinov, Ruth; Gursoy, Attila

2016-10-01

The structures of protein assemblies are important for elucidating cellular processes at the molecular level. Three-dimensional electron microscopy (3DEM) is a powerful method to identify the structures of assemblies, especially those that are challenging to study by crystallography. Here, a new approach, PRISM-EM, is reported to computationally generate plausible structural models using a procedure that combines crystallographic structures and density maps obtained from 3DEM. The predictions are validated against seven available structurally different crystallographic complexes. The models display mean deviations in the backbone of <5 Å. PRISM-EM was further tested on different benchmark sets; the accuracy was evaluated with respect to the structure of the complex, and the correlation with EM density maps and interface predictions were evaluated and compared with those obtained using other methods. PRISM-EM was then used to predict the structure of the ternary complex of the HIV-1 envelope glycoprotein trimer, the ligand CD4 and the neutralizing protein m36.

Segmentation of neuronal structures using SARSA (λ)-based boundary amendment with reinforced gradient-descent curve shape fitting.

PubMed

Zhu, Fei; Liu, Quan; Fu, Yuchen; Shen, Bairong

2014-01-01

The segmentation of structures in electron microscopy (EM) images is very important for neurobiological research. The low resolution neuronal EM images contain noise and generally few features are available for segmentation, therefore application of the conventional approaches to identify the neuron structure from EM images is not successful. We therefore present a multi-scale fused structure boundary detection algorithm in this study. In the algorithm, we generate an EM image Gaussian pyramid first, then at each level of the pyramid, we utilize Laplacian of Gaussian function (LoG) to attain structure boundary, we finally assemble the detected boundaries by using fusion algorithm to attain a combined neuron structure image. Since the obtained neuron structures usually have gaps, we put forward a reinforcement learning-based boundary amendment method to connect the gaps in the detected boundaries. We use a SARSA (λ)-based curve traveling and amendment approach derived from reinforcement learning to repair the incomplete curves. Using this algorithm, a moving point starts from one end of the incomplete curve and walks through the image where the decisions are supervised by the approximated curve model, with the aim of minimizing the connection cost until the gap is closed. Our approach provided stable and efficient structure segmentation. The test results using 30 EM images from ISBI 2012 indicated that both of our approaches, i.e., with or without boundary amendment, performed better than six conventional boundary detection approaches. In particular, after amendment, the Rand error and warping error, which are the most important performance measurements during structure segmentation, were reduced to very low values. The comparison with the benchmark method of ISBI 2012 and the recent developed methods also indicates that our method performs better for the accurate identification of substructures in EM images and therefore useful for the identification of imaging features related to brain diseases.

Segmentation of Neuronal Structures Using SARSA (λ)-Based Boundary Amendment with Reinforced Gradient-Descent Curve Shape Fitting

PubMed Central

Zhu, Fei; Liu, Quan; Fu, Yuchen; Shen, Bairong

2014-01-01

The segmentation of structures in electron microscopy (EM) images is very important for neurobiological research. The low resolution neuronal EM images contain noise and generally few features are available for segmentation, therefore application of the conventional approaches to identify the neuron structure from EM images is not successful. We therefore present a multi-scale fused structure boundary detection algorithm in this study. In the algorithm, we generate an EM image Gaussian pyramid first, then at each level of the pyramid, we utilize Laplacian of Gaussian function (LoG) to attain structure boundary, we finally assemble the detected boundaries by using fusion algorithm to attain a combined neuron structure image. Since the obtained neuron structures usually have gaps, we put forward a reinforcement learning-based boundary amendment method to connect the gaps in the detected boundaries. We use a SARSA (λ)-based curve traveling and amendment approach derived from reinforcement learning to repair the incomplete curves. Using this algorithm, a moving point starts from one end of the incomplete curve and walks through the image where the decisions are supervised by the approximated curve model, with the aim of minimizing the connection cost until the gap is closed. Our approach provided stable and efficient structure segmentation. The test results using 30 EM images from ISBI 2012 indicated that both of our approaches, i.e., with or without boundary amendment, performed better than six conventional boundary detection approaches. In particular, after amendment, the Rand error and warping error, which are the most important performance measurements during structure segmentation, were reduced to very low values. The comparison with the benchmark method of ISBI 2012 and the recent developed methods also indicates that our method performs better for the accurate identification of substructures in EM images and therefore useful for the identification of imaging features related to brain diseases. PMID:24625699

Single-particle cryo-EM using alignment by classification (ABC): the structure of Lumbricus terrestris haemoglobin

PubMed Central

Seer-Linnemayr, Charlotte; Ravelli, Raimond B. G.; Matadeen, Rishi; De Carlo, Sacha; Alewijnse, Bart; Portugal, Rodrigo V.; Pannu, Navraj S.; Schatz, Michael; van Heel, Marin

2017-01-01

Single-particle cryogenic electron microscopy (cryo-EM) can now yield near-atomic resolution structures of biological complexes. However, the reference-based alignment algorithms commonly used in cryo-EM suffer from reference bias, limiting their applicability (also known as the ‘Einstein from random noise’ problem). Low-dose cryo-EM therefore requires robust and objective approaches to reveal the structural information contained in the extremely noisy data, especially when dealing with small structures. A reference-free pipeline is presented for obtaining near-atomic resolution three-dimensional reconstructions from heterogeneous (‘four-dimensional’) cryo-EM data sets. The methodologies integrated in this pipeline include a posteriori camera correction, movie-based full-data-set contrast transfer function determination, movie-alignment algorithms, (Fourier-space) multivariate statistical data compression and unsupervised classification, ‘random-startup’ three-dimensional reconstructions, four-dimensional structural refinements and Fourier shell correlation criteria for evaluating anisotropic resolution. The procedures exclusively use information emerging from the data set itself, without external ‘starting models’. Euler-angle assignments are performed by angular reconstitution rather than by the inherently slower projection-matching approaches. The comprehensive ‘ABC-4D’ pipeline is based on the two-dimensional reference-free ‘alignment by classification’ (ABC) approach, where similar images in similar orientations are grouped by unsupervised classification. Some fundamental differences between X-ray crystallography versus single-particle cryo-EM data collection and data processing are discussed. The structure of the giant haemoglobin from Lumbricus terrestris at a global resolution of ∼3.8 Å is presented as an example of the use of the ABC-4D procedure. PMID:28989723

[INVITED] Coherent perfect absorption of electromagnetic wave in subwavelength structures

NASA Astrophysics Data System (ADS)

Yan, Chao; Pu, Mingbo; Luo, Jun; Huang, Yijia; Li, Xiong; Ma, Xiaoliang; Luo, Xiangang

2018-05-01

Electromagnetic (EM) absorption is a common process by which the EM energy is transformed into other kinds of energy in the absorber, for example heat. Perfect absorption of EM with structures at subwavelength scale is important for many practical applications, such as stealth technology, thermal control and sensing. Coherent perfect absorption arises from the interplay of interference and absorption, which can be interpreted as a time-reversed process of lasing or EM emitting. It provides a promising way for complete absorption in both nanophotonics and electromagnetics. In this review, we discuss basic principles and properties of a coherent perfect absorber (CPA). Various subwavelength structures including thin films, metamaterials and waveguide-based structures to realize CPAs are compared. We also discuss the potential applications of CPAs.

Buried structure for increasing fabrication performance of micromaterial by electromigration

NASA Astrophysics Data System (ADS)

Kimura, Yasuhiro; Saka, Masumi

2016-06-01

The electromigration (EM) technique is a physical synthetic growth method for micro/nanomaterials. EM causes atomic diffusion in a metal line by high-density electron flows. The intentional control of accumulation and relaxation of atoms by EM can lead to the fabrication of a micro/nanomaterial. TiN passivation has been utilized as a component of sample in the EM technique. Although TiN passivation can simplify the cumbersome processes for preparing the sample, the leakage of current naturally occurs because of the conductivity of TiN as a side effect and decreases the performance of micro/nanomaterial fabrication. In the present work, we propose a buried structure, which contributes to significantly decreasing the current for fabricating an Al micromaterial by confining the current flow in the EM technique. The fabrication performance was evaluated based on the threshold current for fabricating an Al micromaterial using the buried structure and the previous structure with the leakage of current.

ATOMIC RESOLUTION CRYO ELECTRON MICROSCOPY OF MACROMOLECULAR COMPLEXES

PubMed Central

ZHOU, Z. HONG

2013-01-01

Single-particle cryo electron microscopy (cryoEM) is a technique for determining three-dimensional (3D) structures from projection images of molecular complexes preserved in their “native,” noncrystalline state. Recently, atomic or near-atomic resolution structures of several viruses and protein assemblies have been determined by single-particle cryoEM, allowing ab initio atomic model building by following the amino acid side chains or nucleic acid bases identifiable in their cryoEM density maps. In particular, these cryoEM structures have revealed extended arms contributing to molecular interactions that are otherwise not resolved by the conventional structural method of X-ray crystallography at similar resolutions. High-resolution cryoEM requires careful consideration of a number of factors, including proper sample preparation to ensure structural homogeneity, optimal configuration of electron imaging conditions to record high-resolution cryoEM images, accurate determination of image parameters to correct image distortions, efficient refinement and computation to reconstruct a 3D density map, and finally appropriate choice of modeling tools to construct atomic models for functional interpretation. This progress illustrates the power of cryoEM and ushers it into the arsenal of structural biology, alongside conventional techniques of X-ray crystallography and NMR, as a major tool (and sometimes the preferred one) for the studies of molecular interactions in supramolecular assemblies or machines. PMID:21501817

Giant amplification in degenerate band edge slow-wave structures interacting with an electron beam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Othman, Mohamed A. K.; Veysi, Mehdi; Capolino, Filippo

2016-03-15

We propose a new amplification regime based on a synchronous operation of four degenerate electromagnetic (EM) modes in a slow-wave structure and the electron beam, referred to as super synchronization. These four EM modes arise in a Fabry-Pérot cavity when degenerate band edge (DBE) condition is satisfied. The modes interact constructively with the electron beam resulting in superior amplification. In particular, much larger gains are achieved for smaller beam currents compared to conventional structures based on synchronization with only a single EM mode. We demonstrate giant gain scaling with respect to the length of the slow-wave structure compared to conventionalmore » Pierce type single mode traveling wave tube amplifiers. We construct a coupled transmission line model for a loaded waveguide slow-wave structure exhibiting a DBE, and investigate the phenomenon of giant gain via super synchronization using the Pierce model generalized to multimode interaction.« less

Recent progress in structural biology: lessons from our research history.

PubMed

Nitta, Ryo; Imasaki, Tsuyoshi; Nitta, Eriko

2018-05-16

The recent 'resolution revolution' in structural analyses of cryo-electron microscopy (cryo-EM) has drastically changed the research strategy for structural biology. In addition to X-ray crystallography and nuclear magnetic resonance spectroscopy, cryo-EM has achieved the structural analysis of biological molecules at near-atomic resolution, resulting in the Nobel Prize in Chemistry 2017. The effect of this revolution has spread within the biology and medical science fields affecting everything from basic research to pharmaceutical development by visualizing atomic structure. As we have used cryo-EM as well as X-ray crystallography since 2000 to elucidate the molecular mechanisms of the fundamental phenomena in the cell, here we review our research history and summarize our findings. In the first half of the review, we describe the structural mechanisms of microtubule-based motility of molecular motor kinesin by using a joint cryo-EM and X-ray crystallography method. In the latter half, we summarize our structural studies on transcriptional regulation by X-ray crystallography of in vitro reconstitution of a multi-protein complex.

Emergency medical services key performance measurement in Asian cities.

PubMed

Rahman, Nik Hisamuddin; Tanaka, Hideharu; Shin, Sang Do; Ng, Yih Yng; Piyasuwankul, Thammapad; Lin, Chih-Hao; Ong, Marcus Eng Hock

2015-01-01

One of the key principles in the recommended standards is that emergency medical service (EMS) providers should continuously monitor the quality and safety of their services. This requires service providers to implement performance monitoring using appropriate and relevant measures including key performance indicators. In Asia, EMS systems are at different developmental phases and maturity. This will create difficultly in benchmarking or assessing the quality of EMS performance across the region. An attempt was made to compare the EMS performance index based on the structure, process, and outcome analysis. The data was collected from the Pan-Asian Resuscitation Outcome Study (PAROS) data among few Asian cities, namely, Tokyo, Osaka, Singapore, Bangkok, Kuala Lumpur, Taipei, and Seoul. The parameters of inclusions were broadly divided into structure, process, and outcome measurements. The data was collected by the site investigators from each city and keyed into the electronic web-based data form which is secured strictly by username and passwords. Generally, there seems to be a more uniformity for EMS performance parameters among the more developed EMS systems. The major problem with the EMS agencies in the cities of developing countries like Bangkok and Kuala Lumpur is inadequate or unavailable data pertaining to EMS performance. There is non-uniformity in the EMS performance measurement across the Asian cities. This creates difficulty for EMS performance index comparison and benchmarking. Hopefully, in the future, collaborative efforts such as the PAROS networking group will further enhance the standardization in EMS performance reporting across the region.

NOAA Office of Exploration and Research > About OER > Strategic Plan

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Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan Media News Room OER Symposium Overview Organization Guiding Documents Organizational Structure Map of Strategic Plan Home About OER Overview Organization Guiding Documents Organizational Structure Map of Staff

NOAA Office of Exploration and Research > About OER > Overview

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Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan Media News Room OER Symposium Overview Organization Guiding Documents Organizational Structure Map of Overview Home About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and

NOAA Office of Exploration and Research > About OER > Organization >

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Organizational Structure Saturday, May 26, 2018 THIS WEBSITE IS NO LONGER BEING UPDATED OR About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Overview Website & Social Media News Room OER Symposium Guiding Documents Organizational Structure Map

NOAA Office of Exploration and Research > About OER > Contact Us

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Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan Media News Room OER Symposium Overview Organization Guiding Documents Organizational Structure Map of Contact Us Home About OER Overview Organization Guiding Documents Organizational Structure Map of Staff

NOAA Office of Exploration and Research > About OER > Program Review

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Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan Media News Room OER Symposium Overview Organization Guiding Documents Organizational Structure Map of Program Review Home About OER Overview Organization Guiding Documents Organizational Structure Map of

NOAA Office of Exploration and Research > About OER > Organization > Map of

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About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Overview Website & Social Media News Room OER Symposium Guiding Documents Organizational Structure Map About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate

Facilities | Buildings | NREL

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state-of-the-art and unique equipment for analyzing a wide spectrum of building energy efficiency building's energy use and make adjustments. Low-Energy Parking Structure Photo of the parking structure on structure in February 2012. The structure's estimated energy use is 42 kilowatt-hours per parking stall

Study of plasma-based stable and ultra-wideband electromagnetic wave absorption for stealth application

NASA Astrophysics Data System (ADS)

Xuyang, CHEN; Fangfang, SHEN; Yanming, LIU; Wei, AI; Xiaoping, LI

2018-06-01

A plasma-based stable, ultra-wideband electromagnetic (EM) wave absorber structure is studied in this paper for stealth applications. The stability is maintained by a multi-layer structure with several plasma layers and dielectric layers distributed alternately. The plasma in each plasma layer is designed to be uniform, whereas it has a discrete nonuniform distribution from the overall view of the structure. The nonuniform distribution of the plasma is the key to obtaining ultra-wideband wave absorption. A discrete Epstein distribution model is put forward to constrain the nonuniform electron density of the plasma layers, by which the wave absorption range is extended to the ultra-wideband. Then, the scattering matrix method (SMM) is employed to analyze the electromagnetic reflection and absorption of the absorber structure. In the simulation, the validation of the proposed structure and model in ultra-wideband EM wave absorption is first illustrated by comparing the nonuniform plasma model with the uniform case. Then, the influence of various parameters on the EM wave reflection of the plasma are simulated and analyzed in detail, verifying the EM wave absorption performance of the absorber. The proposed structure and model are expected to be superior in some realistic applications, such as supersonic aircraft.

Sensitivity of PZT Impedance Sensors for Damage Detection of Concrete Structures

PubMed Central

Yang, Yaowen; Hu, Yuhang; Lu, Yong

2008-01-01

Piezoelectric ceramic Lead Zirconate Titanate (PZT) based electro-mechanical impedance (EMI) technique for structural health monitoring (SHM) has been successfully applied to various engineering systems. However, fundamental research work on the sensitivity of the PZT impedance sensors for damage detection is still in need. In the traditional EMI method, the PZT electro-mechanical (EM) admittance (inverse of the impedance) is used as damage indicator, which is difficult to specify the effect of damage on structural properties. This paper uses the structural mechanical impedance (SMI) extracted from the PZT EM admittance signature as the damage indicator. A comparison study on the sensitivity of the EM admittance and the structural mechanical impedance to the damages in a concrete structure is conducted. Results show that the SMI is more sensitive to the damage than the EM admittance thus a better indicator for damage detection. Furthermore, this paper proposes a dynamic system consisting of a number of single-degree-of-freedom elements with mass, spring and damper components to model the SMI. A genetic algorithm is employed to search for the optimal value of the unknown parameters in the dynamic system. An experiment is carried out on a two-storey concrete frame subjected to base vibrations that simulate earthquake. A number of PZT sensors are regularly arrayed and bonded to the frame structure to acquire PZT EM admittance signatures. The relationship between the damage index and the distance of the PZT sensor from the damage is studied. Consequently, the sensitivity of the PZT sensors is discussed and their sensing region in concrete is derived. PMID:27879711

X-ray and cryo-EM structures of inhibitor-bound cytochrome bc 1 complexes for structure-based drug discovery

PubMed Central

Amporndanai, Kangsa; O’Neill, Paul M.

2018-01-01

Cytochrome bc 1, a dimeric multi-subunit electron-transport protein embedded in the inner mitochondrial membrane, is a major drug target for the treatment and prevention of malaria and toxoplasmosis. Structural studies of cytochrome bc 1 from mammalian homologues co-crystallized with lead compounds have underpinned structure-based drug design to develop compounds with higher potency and selectivity. However, owing to the limited amount of cytochrome bc 1 that may be available from parasites, all efforts have been focused on homologous cytochrome bc 1 complexes from mammalian species, which has resulted in the failure of some drug candidates owing to toxicity in the host. Crystallographic studies of the native parasite proteins are not feasible owing to limited availability of the proteins. Here, it is demonstrated that cytochrome bc 1 is highly amenable to single-particle cryo-EM (which uses significantly less protein) by solving the apo and two inhibitor-bound structures to ∼4.1 Å resolution, revealing clear inhibitor density at the binding site. Therefore, cryo-EM is proposed as a viable alternative method for structure-based drug discovery using both host and parasite enzymes. PMID:29765610

Vladimir V. Lunin | NREL

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Protein crystallization X-ray diffraction data collection Protein structure determination Obtaining structures of protein-ligand complexes Site-directed mutagenesis Structure-function relationship Enzymatic CelA," Science (2013) "Sequence, Structure, and Evolution of Cellulases in Glycoside

Tools for Model Building and Optimization into Near-Atomic Resolution Electron Cryo-Microscopy Density Maps.

PubMed

DiMaio, F; Chiu, W

2016-01-01

Electron cryo-microscopy (cryoEM) has advanced dramatically to become a viable tool for high-resolution structural biology research. The ultimate outcome of a cryoEM study is an atomic model of a macromolecule or its complex with interacting partners. This chapter describes a variety of algorithms and software to build a de novo model based on the cryoEM 3D density map, to optimize the model with the best stereochemistry restraints and finally to validate the model with proper protocols. The full process of atomic structure determination from a cryoEM map is described. The tools outlined in this chapter should prove extremely valuable in revealing atomic interactions guided by cryoEM data. © 2016 Elsevier Inc. All rights reserved.

Sensitivity of PZT Impedance Sensors for Damage Detection of Concrete Structures.

PubMed

Yang, Yaowen; Hu, Yuhang; Lu, Yong

2008-01-21

Piezoelectric ceramic Lead Zirconate Titanate (PZT) based electro-mechanicalimpedance (EMI) technique for structural health monitoring (SHM) has been successfullyapplied to various engineering systems. However, fundamental research work on thesensitivity of the PZT impedance sensors for damage detection is still in need. In thetraditional EMI method, the PZT electro-mechanical (EM) admittance (inverse of theimpedance) is used as damage indicator, which is difficult to specify the effect of damage onstructural properties. This paper uses the structural mechanical impedance (SMI) extractedfrom the PZT EM admittance signature as the damage indicator. A comparison study on thesensitivity of the EM admittance and the structural mechanical impedance to the damages ina concrete structure is conducted. Results show that the SMI is more sensitive to the damagethan the EM admittance thus a better indicator for damage detection. Furthermore, this paperproposes a dynamic system consisting of a number of single-degree-of-freedom elementswith mass, spring and damper components to model the SMI. A genetic algorithm isemployed to search for the optimal value of the unknown parameters in the dynamic system.An experiment is carried out on a two-storey concrete frame subjected to base vibrations thatsimulate earthquake. A number of PZT sensors are regularly arrayed and bonded to the framestructure to acquire PZT EM admittance signatures. The relationship between the damageindex and the distance of the PZT sensor from the damage is studied. Consequently, thesensitivity of the PZT sensors is discussed and their sensing region in concrete is derived.

Structural Test Laboratory | Water Power | NREL

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Structural Test Laboratory Structural Test Laboratory NREL engineers design and configure structural components can validate models, demonstrate system reliability, inform design margins, and assess , including mass and center of gravity, to ensure compliance with design goals Dynamic Characterization Use

OpenSees

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, through soil-structure interaction, to structural response. New computer simulation tools are necessary to of structures and soils to investigate challenging problems in soil-structure-foundation interaction including foundations and soils is used to study the effects of soil liquefaction and permanent

Sang-Don Han | NREL

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between 1) electrolyte material structure (i.e., solvent/anion structure and solvation state of cations presence of organic foulants," Desalination (2009). "Influence of the heterogeneous structure on

Nuclear Data Networks

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calibrations. NSDD The international network of Nuclear Structure and Decay Data evaluators Group of and updating of nuclear structure data contained in Evaluated Nuclear Structure Data File (ENSDF

Joint Chiefs of Staff > Leadership

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Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Structure Joint Staff Organizational Chart Joint Chiefs of Staff Links Home Today in DOD About DOD Top Issues News Photos/Videos

Brandon Knott | NREL

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-6223 Research Interests Molecular mechanisms of cellulose-degrading enzymes Structure-function relationships of biomass-derived polymers Structure-function relationships in glycoside hydrolases Methane potential protein engineering targets. Structure-Function Relationships of Biomass-Derived Polymers

The structure of a cholesterol-trapping protein

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Date February 28, 2003 Date Berkeley Lab Science Beat Berkeley Lab Science Beat The structure of a Institute researchers determined the three-dimensional structure of a protein that controls cholesterol level in the bloodstream. Knowing the structure of the protein, a cellular receptor that ensnares

A corkscrew model for dynamin constriction

PubMed Central

Mears, Jason A.; Ray, Pampa; Hinshaw, Jenny E.

2007-01-01

SUMMARY Numerous vesiculation processes throughout the eukaryotic cell are dependant on the protein dynamin, a large GTPase that constricts lipid bilayers. We have combined x-ray crystallography and cryo-electron microscopy (cryo-EM) data to generate a coherent model of dynamin-mediated membrane constriction. X-ray structures of mammalian GTPase and pleckstrin homology (PH) domains of dynamin were fit to cryo-EM structures of human ΔPRD dynamin helices bound to lipid in non-constricted and constricted states. Proteolysis and immunogold labeling experiments confirm the topology of dynamin domains predicted from the helical arrays. Based on the fitting, an observed twisting motion of the GTPase, middle and GTPase-effector domains coincides with conformational changes determined by cryo-EM. We propose a corkscrew model for dynamin constriction based on these motions and predict regions of sequence important for dynamin function as potential targets for future mutagenic and structural studies. PMID:17937909

Argonne Physics Division - E-906/SeaQuest

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measure the quark and antiquark structure of the nucleon and the modifications to that structure which experiment will also examine the modifications to the antiquark structure of the proton from nuclear binding

| NREL

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of NREL's Computational Science Center, where he uses electronic structure calculations and other introductory chemistry and physical chemistry. Research Interests Electronic structure and dynamics in the quantum/classical molecular dynamics simulation|Coupling of molecular electronic structure to

Stephan Lany | NREL

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scientist with a background in electronic structure calculations for semiconducting materials. He joined Program. Research Interests His research interests include prediction of band-structure, optical , electrical, and transport properties from electronic structure theory; photovoltaic and thermoelectric

StructMap: Elastic Distance Analysis of Electron Microscopy Maps for Studying Conformational Changes.

PubMed

Sanchez Sorzano, Carlos Oscar; Alvarez-Cabrera, Ana Lucia; Kazemi, Mohsen; Carazo, Jose María; Jonić, Slavica

2016-04-26

Single-particle electron microscopy (EM) has been shown to be very powerful for studying structures and associated conformational changes of macromolecular complexes. In the context of analyzing conformational changes of complexes, distinct EM density maps obtained by image analysis and three-dimensional (3D) reconstruction are usually analyzed in 3D for interpretation of structural differences. However, graphic visualization of these differences based on a quantitative analysis of elastic transformations (deformations) among density maps has not been done yet due to a lack of appropriate methods. Here, we present an approach that allows such visualization. This approach is based on statistical analysis of distances among elastically aligned pairs of EM maps (one map is deformed to fit the other map), and results in visualizing EM maps as points in a lower-dimensional distance space. The distances among points in the new space can be analyzed in terms of clusters or trajectories of points related to potential conformational changes. The results of the method are shown with synthetic and experimental EM maps at different resolutions. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Structural Testing Laboratory Video Transcript | Wind | NREL

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be able to structurally validate wind turbine blades and components. Ryan Beach, Structural Engineer weeks. Scott Hughes: Since 1990, NREL has tested over 200 wind turbine blades with over 10,000 strain blades. Text on Screen: Learn more about NREL's structural research facilities at nrel.gov/wind

Robert Hofstadter, Electron Scattering, the Structure of the Nucleons, and

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, Electron Scattering, the Structure of the Nucleons, and Scintillation Counters Resources with Additional -point particles and therefore possessed structure. For this work Hofstadter was awarded the Nobel Prize structure of the nucleons, and scintillation counters is available in electronic documents and on the Web

Mirjana Dimitrievska | NREL

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understanding the structure-dependent vibrational properties and reorientational behavior of different alkali Sad, Serbia Featured Publications M. Dimitrievska et al., "Structure-dependent vibrational : Structure and luminescence," J. Phys. Chem. C 120(33), 18887-18894 (2016). DOI: http://dx.doi.org

Structural Biology Center

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structure of RCC2 and revealed one RCC1-like domain with a unique β-hairpin that is requisite for RCC2 Determinants Structure-guided design of an Hsp90β N-terminal isoform-selective inhibitor Nat Commun. 2018 Jan training for building #446 and ANL. MCSG's structure determination platform is well established, and

The Evolving Market Structure of the U.S. Residential Solar PV Installation

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Solar PV Installation Industry, 2000-2016 The Evolving Market Structure of the U.S. Residential Solar PV residential solar photovoltaic (PV) system and that the residential PV installation industry has become more concentrated over time. From 2000 to 2016, the U.S. residential solar photovoltaic (PV) installation industry

NOAA Office of Exploration and Research > About OER > Program Review >

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OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations

National Nuclear Data Center

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reaction data Sigma Retrieval & Plotting Nuclear structure & decay Data Nuclear Science References Experimental Unevaluated Nuclear Data List Evaluated Nuclear Structure Data File NNDC databases Ground and isomeric states properties Nuclear structure & decay data journal Nuclear reaction model code Tools and

Biographies

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Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Senior Leaders Gen. Joseph F Biography All Joint Staff Biographies Thomas F. Carney, Vice Director for Force Structure, Resources,and

Vivek S. Bharadwaj | NREL

Science.gov Websites

Interests Vivek's interests broadly span across protein structure and dynamics, reaction mechanisms, and energetics and kinetics from first principles Protein structure prediction and docking Education PhD structure on the fumarate addition mechanism - a gas-phase ab initio study," Physical Chemistry

NOAA Office of Exploration and Research > About OER > Program Review >

Science.gov Websites

About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate

Modeling protein structure at near atomic resolutions with Gorgon.

PubMed

Baker, Matthew L; Abeysinghe, Sasakthi S; Schuh, Stephen; Coleman, Ross A; Abrams, Austin; Marsh, Michael P; Hryc, Corey F; Ruths, Troy; Chiu, Wah; Ju, Tao

2011-05-01

Electron cryo-microscopy (cryo-EM) has played an increasingly important role in elucidating the structure and function of macromolecular assemblies in near native solution conditions. Typically, however, only non-atomic resolution reconstructions have been obtained for these large complexes, necessitating computational tools for integrating and extracting structural details. With recent advances in cryo-EM, maps at near-atomic resolutions have been achieved for several macromolecular assemblies from which models have been manually constructed. In this work, we describe a new interactive modeling toolkit called Gorgon targeted at intermediate to near-atomic resolution density maps (10-3.5 Å), particularly from cryo-EM. Gorgon's de novo modeling procedure couples sequence-based secondary structure prediction with feature detection and geometric modeling techniques to generate initial protein backbone models. Beyond model building, Gorgon is an extensible interactive visualization platform with a variety of computational tools for annotating a wide variety of 3D volumes. Examples from cryo-EM maps of Rotavirus and Rice Dwarf Virus are used to demonstrate its applicability to modeling protein structure. Copyright © 2011 Elsevier Inc. All rights reserved.

David W. Mulder, Ph.D. | NREL

Science.gov Websites

an emphasis on identifying unique structure-functions relationships and molecular determinates of exploring structure-function relationships of redox metalloenzymes Designated Area Representative of the ]-hydrogenase H-cluster assembly revealed in the structure of HydAΔEFG" Nature (2010) Illustration labeled

Fermi Research Alliance LLC

Science.gov Websites

dark matter structure in universe The findings - the most accurate made of the universe's present large -scale structure - support the dark matter/dark energy model. Read More Muon g-2 Muon magnet's moment has massive international experiment. Read More Dark Energy Camera DES reveals most accurate measurement of

Bill McMahon | NREL

Science.gov Websites

career at NREL in 1995 by conducting scanning tunneling microscope (STM) studies of the atomic structure revealed a new strain-induced step structure and contributed to the development of world-record-efficiency NREL's Computational Materials Science team, probing the atomic structure of dislocations in III-V

Smoot Cosmology Group

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the Cosmic Background Radiation as a tool to understand the structure and history of the Universe and its relation to the structure of space-time. Likewise, gravitational lensing, the search for evidence of cosmic strings, and the cosmic infrared background tell us about the structure of space-time and

Pulse - Accelerator Science in Medicine

Science.gov Websites

the structure of biological molecules. They use the energy that charged particles emit when powerful than the sun and focused on a pinpoint. Deciphering the structure of proteins is key to understanding biological processes and healing disease. To determine a protein’s structure, researchers direct

Johann Deisenhofer, Crystallography, and Proteins

Science.gov Websites

research using X-ray crystallography to elucidate for the first time the three-dimensional structure of a large membrane-bound protein molecule. This structure helped explain the process of photosynthesis, by a protein structure determination that relied on complementary features of two different beam lines

Cryo-EM structure of haemoglobin at 3.2 Å determined with the Volta phase plate

NASA Astrophysics Data System (ADS)

Khoshouei, Maryam; Radjainia, Mazdak; Baumeister, Wolfgang; Danev, Radostin

2017-06-01

With the advent of direct electron detectors, the perspectives of cryo-electron microscopy (cryo-EM) have changed in a profound way. These cameras are superior to previous detectors in coping with the intrinsically low contrast and beam-induced motion of radiation-sensitive organic materials embedded in amorphous ice, and hence they have enabled the structure determination of many macromolecular assemblies to atomic or near-atomic resolution. Nevertheless, there are still limitations and one of them is the size of the target structure. Here, we report the use of a Volta phase plate in determining the structure of human haemoglobin (64 kDa) at 3.2 Å. Our results demonstrate that this method can be applied to complexes that are significantly smaller than those previously studied by conventional defocus-based approaches. Cryo-EM is now close to becoming a fast and cost-effective alternative to crystallography for high-resolution protein structure determination.

About the Joint Chiefs of Staff

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JCS: Search Home Media News Photos Videos Publications About The Joint Staff Chairman Vice Chairman J8 | Force Structure, Resources & Assessment Contact Joint Staff Structure Home : About About the Joint Chiefs of Staff Download the CJCS Historic Guide The Joint Chiefs of Staff consist of the Chairman

Los Angeles Tall Buildings Structural Design Council

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Los Angeles Tall Buildings Structural Design Council Home News Archives Members Mailing Address LATBSDC c/o John A. Martin & Associates 950 South Grand Ave 4th Floor Los Angeles, CA 90015, USA Phone (213) 483-6490 Fax (213) 483-3084 Welcome Welcome to the Los Angeles Tall Buildings Structural Design

Nuclear Data Sheets page at the NNDC

Science.gov Websites

Data Sheets is a journal primarily devoted to the publication of evaluated nuclear structure and decay ; neutron, proton, alpha, cluster and cluster emission; fission. Nuclear structure and decay data are basis. The ENSDF database is the source for the nuclear structure and decay articles, which deal with a

BLAST for Behind-the-Meter Applications Lite Tool | Transportation Research

Science.gov Websites

provided by NREL's PV Watts calculator. A generic utility rate structure framework makes it possible to the BLAST documentation for proper CSV formatting. Rate structure values Define demand charges and energy costs to best represent your utility rate structure of interest. Demand charges and energy costs

Active sensors for health monitoring of aging aerospace structures

NASA Astrophysics Data System (ADS)

Giurgiutiu, Victor; Redmond, James M.; Roach, Dennis P.; Rackow, Kirk

2000-06-01

A project to develop non-intrusive active sensors that can be applied on existing aging aerospace structures for monitoring the onset and progress of structural damage (fatigue cracks and corrosion) is presented. The state of the art in active sensors structural health monitoring and damage detection is reviewed. Methods based on (a) elastic wave propagation and (b) electro-mechanical (E/M) impedance technique are cited and briefly discussed. The instrumentation of these specimens with piezoelectric active sensors is illustrated. The main detection strategies (E/M impedance for local area detection and wave propagation for wide area interrogation) are discussed. The signal processing and damage interpretation algorithms are tuned to the specific structural interrogation method used. In the high frequency E/M impedance approach, pattern recognition methods are used to compare impedance signatures taken at various time intervals and to identify damage presence and progression from the change in these signatures. In the wave propagation approach, the acousto- ultrasonic methods identifying additional reflection generated from the damage site and changes in transmission velocity and phase are used. Both approaches benefit from the use of artificial intelligence neural networks algorithms that can extract damage features based on a learning process. Design and fabrication of a set of structural specimens representative of aging aerospace structures is presented. Three built-up specimens, (pristine, with cracks, and with corrosion damage) are used. The specimen instrumentation with active sensors fabricated at the University of South Carolina is illustrated. Preliminary results obtained with the E/M impedance method on pristine and cracked specimens are presented.

Experimental Realization of a Reflections-Free Compact Delay Line Based on a Photonic Topological Insulator

PubMed Central

Lai, Kueifu; Ma, Tsuhsuang; Bo, Xiao; Anlage, Steven; Shvets, Gennady

2016-01-01

Electromagnetic (EM) waves propagating through an inhomogeneous medium are generally scattered whenever the medium’s electromagnetic properties change on the scale of a single wavelength. This fundamental phenomenon constrains how optical structures are designed and interfaced with each other. Recent theoretical work indicates that electromagnetic structures collectively known as photonic topological insulators (PTIs) can be employed to overcome this fundamental limitation, thereby paving the way for ultra-compact photonic structures that no longer have to be wavelength-scale smooth. Here we present the first experimental demonstration of a photonic delay line based on topologically protected surface electromagnetic waves (TPSWs) between two PTIs which are the EM counterparts of the quantum spin-Hall topological insulators in condensed matter. Unlike conventional guided EM waves that do not benefit from topological protection, TPSWs are shown to experience multi-wavelength reflection-free time delays when detoured around sharply-curved paths, thus offering a unique paradigm for compact and efficient wave buffers and other devices. PMID:27345575

Wood-Boring Gribbles Intrigue Researchers | News | NREL

Science.gov Websites

the crystal structure of a key enzyme produced by the gribble. The report was recently published in . One of them, dubbed Cel7B, is the subject of the latest paper describing its crystal structure. " diffraction to solve the structure of the gribble enzyme and biochemical techniques to understand its activity

Enzyme's Worth to Biofuels Shown in Latest NREL Research | News | NREL

Science.gov Websites

, and Yannick Bomble with the X-ray diffraction source used to determine the structure of the C. bescii whether their crystalline structure is simple or highly complex. No other enzyme has shown that ability cellulosic biofuels from becoming a commercial reality. The crystalline structure of cellulose fiber in plant

Computational Modeling | Bioenergy | NREL

Science.gov Websites

molecules dissociates and an H-H pair is formed. The atomic structure of state 3 is shown in the lower inset -dissociation of the first H2 molecule. The structure and partial charge density (at the highest occupied band depicted by the illustration to the left determined the structure and binding orientation of several

Willis Lamb, Jr., the Hydrogen Atom, and the Lamb Shift

Science.gov Websites

1955, Lamb won the Nobel Prize in Physics for his discoveries concerning "the fine structure of , May 7 - September 30, 1979 Fine Structure of the Hydrogen Atom, Part I; Part II; Part III; Part IV ; Part V; Part VI (from Physical Review 1950-1953) Microwave Technique for Determining the Fine Structure

NOAA Office of Exploration and Research > Education > NOAA Initiatives

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Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan Evaluation Education NOAA Initiatives Home About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan 2014 Funding Opportunities Contact Us Program

NOAA Office of Exploration and Research > Education > Alliance Partners

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Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan Evaluation Education Alliance Partners Home About OER Overview Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan 2014 Funding Opportunities Contact Us Program

A corkscrew model for dynamin constriction.

PubMed

Mears, Jason A; Ray, Pampa; Hinshaw, Jenny E

2007-10-01

Numerous vesiculation processes throughout the eukaryotic cell are dependent on the protein dynamin, a large GTPase that constricts lipid bilayers. We have combined X-ray crystallography and cryo-electron microscopy (cryo-EM) data to generate a coherent model of dynamin-mediated membrane constriction. GTPase and pleckstrin homology domains of dynamin were fit to cryo-EM structures of human dynamin helices bound to lipid in nonconstricted and constricted states. Proteolysis and immunogold labeling experiments confirm the topology of dynamin domains predicted from the helical arrays. Based on the fitting, an observed twisting motion of the GTPase, middle, and GTPase effector domains coincides with conformational changes determined by cryo-EM. We propose a corkscrew model for dynamin constriction based on these motions and predict regions of sequence important for dynamin function as potential targets for future mutagenic and structural studies.

Brian K. Kobilka and G-protein-coupled Receptors (GPCR)

Science.gov Websites

the laboratory's Advanced Photon Source (APS) to make the first discovery of the structure of a human the structure of β2AR at the exact moment that the protein-receptor complex signals across the carrying out its biological mission. ... In order to obtain the structure of a GPCR, Kobilka and his

Michael Levitt and Computational Biology

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molecular structures, compute structural changes, refine experimental structure, model enzyme catalysis and (May 2004) Top Some links on this page may take you to non-federal websites. Their policies may differ

Contemporary evidence-based practice in Canadian emergency medical services: a vision for integrating evidence into clinical and policy decision-making.

PubMed

Jensen, Jan L; Travers, Andrew H

2017-05-01

Nationally, emphasis on the importance of evidence-based practice (EBP) in emergency medicine and emergency medical services (EMS) has continuously increased. However, meaningful incorporation of effective and sustainable EBP into clinical and administrative decision-making remains a challenge. We propose a vision for EBP in EMS: Canadian EMS clinicians and leaders will understand and use the best available evidence for clinical and administrative decision-making, to improve patient health outcomes, the capability and quality of EMS systems of care, and safety of patients and EMS professionals. This vision can be implemented with the use of a structure, process, system, and outcome taxonomy to identify current barriers to true EBP, to recognize the opportunities that exist, and propose corresponding recommended strategies for local EMS agencies and at the national level. Framing local and national discussions with this approach will be useful for developing a cohesive and collaborative Canadian EBP strategy.

Ilya Prigogine, Chaos, and Dissipative Structures

Science.gov Websites

research helped create a greater understanding of the role of time in the physical sciences and biology. He " to describe the coherent space-time structures that form in open systems in which an exchange of because in these systems the arrow of time becomes manifest. Prigogine viewed the arrow of time and

Computational methods for constructing protein structure models from 3D electron microscopy maps.

PubMed

Esquivel-Rodríguez, Juan; Kihara, Daisuke

2013-10-01

Protein structure determination by cryo-electron microscopy (EM) has made significant progress in the past decades. Resolutions of EM maps have been improving as evidenced by recently reported structures that are solved at high resolutions close to 3Å. Computational methods play a key role in interpreting EM data. Among many computational procedures applied to an EM map to obtain protein structure information, in this article we focus on reviewing computational methods that model protein three-dimensional (3D) structures from a 3D EM density map that is constructed from two-dimensional (2D) maps. The computational methods we discuss range from de novo methods, which identify structural elements in an EM map, to structure fitting methods, where known high resolution structures are fit into a low-resolution EM map. A list of available computational tools is also provided. Copyright © 2013 Elsevier Inc. All rights reserved.

Electromagnetic wave absorption properties of cement based composites using helical carbon fibers as absorbent

NASA Astrophysics Data System (ADS)

Xie, Shuai; Wang, Jing; Wang, Wufeng; Hou, Guoyan; Li, Bin; Shui, Zhonghe; Ji, Zhijiang

2018-02-01

In order to develop a cement based composites with high electromagnetic (EM) wave absorbing performance, helical carbon fibers (HCFs) were added into the cement matrix as an absorbent. The reflection loss (RL) of the prepared HCFs/cement based composites was studied by arched testing method in the frequency ranges of 1-8 GHz and 8-18 GHz. The results show that the EM wave absorption properties of the cement based composites can be evidently enhanced by the addition of HCFs. The composites with 1.5% HCFs exhibits optimum EM wave absorption performance in the frequency range of 1-8 GHz. However, in 8-18 GHz frequency range, the EM wave absorption performance of the cement composites with 1% HCFs is much better than others. The RL values of the prepared HCFs/cement based composites are less than -5 dB in the whole testing frequency regions, which can be attributed to the strong dielectric loss ability and unique chiral structure of HCFs.

The Organization and Structure to Areas of NWS Headquarters - NOAA's

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homepage National Oceanic and Atmospheric Administration's Select to go to the NWS homepage National ; Technology | Office of Hydrologic Development | Office of Operational Systems | Office of Climate, Water Atmospheric Administration Biography Headquarters National Weather Service Headquarters Structure Assistant

Software Applications on the Peregrine System | High-Performance Computing

Science.gov Websites

programming and optimization. Gaussian Chemistry Program for calculating molecular electronic structure and Materials Science Open-source classical molecular dynamics program designed for massively parallel systems framework Q-Chem Chemistry ab initio quantum chemistry package for predictin molecular structures

A deep convolutional neural network approach to single-particle recognition in cryo-electron microscopy.

PubMed

Zhu, Yanan; Ouyang, Qi; Mao, Youdong

2017-07-21

Single-particle cryo-electron microscopy (cryo-EM) has become a mainstream tool for the structural determination of biological macromolecular complexes. However, high-resolution cryo-EM reconstruction often requires hundreds of thousands of single-particle images. Particle extraction from experimental micrographs thus can be laborious and presents a major practical bottleneck in cryo-EM structural determination. Existing computational methods for particle picking often use low-resolution templates for particle matching, making them susceptible to reference-dependent bias. It is critical to develop a highly efficient template-free method for the automatic recognition of particle images from cryo-EM micrographs. We developed a deep learning-based algorithmic framework, DeepEM, for single-particle recognition from noisy cryo-EM micrographs, enabling automated particle picking, selection and verification in an integrated fashion. The kernel of DeepEM is built upon a convolutional neural network (CNN) composed of eight layers, which can be recursively trained to be highly "knowledgeable". Our approach exhibits an improved performance and accuracy when tested on the standard KLH dataset. Application of DeepEM to several challenging experimental cryo-EM datasets demonstrated its ability to avoid the selection of un-wanted particles and non-particles even when true particles contain fewer features. The DeepEM methodology, derived from a deep CNN, allows automated particle extraction from raw cryo-EM micrographs in the absence of a template. It demonstrates an improved performance, objectivity and accuracy. Application of this novel method is expected to free the labor involved in single-particle verification, significantly improving the efficiency of cryo-EM data processing.

Physics-based simulation of EM and SM in TSV-based 3D IC structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kteyan, Armen; Sukharev, Valeriy; Zschech, Ehrenfried

2014-06-19

Evolution of stresses in through-silicon-vias (TSVs) and in the TSV landing pad due to the stress migration (SM) and electromigration (EM) phenomena are considered. It is shown that an initial stress distribution existing in a TSV depends on its architecture and copper fill technology. We demonstrate that in the case of proper copper annealing the SM-induced redistribution of atoms results in uniform distributions of the hydrostatic stress and concentration of vacancies along each segment. In this case, applied EM stressing generates atom migration that is characterized by kinetics depending on the preexisting equilibrium concentration of vacancies. Stress-induced voiding in TSVmore » is considered. EM induced voiding in TSV landing pad is analyzed in details.« less

Two Argonne scientists named 2012 AAAS fellows | Argonne National

Science.gov Websites

"contributions to understanding structural dynamics of molecular excited states with special . "I'm really interested in how molecules respond to light and how light could influence molecular is being honored for her "contributions to understanding structural dynamics of molecular

A Fast and Effective Microfluidic Spraying-Plunging Method for High-Resolution Single-Particle Cryo-EM.

PubMed

Feng, Xiangsong; Fu, Ziao; Kaledhonkar, Sandip; Jia, Yuan; Shah, Binita; Jin, Amy; Liu, Zheng; Sun, Ming; Chen, Bo; Grassucci, Robert A; Ren, Yukun; Jiang, Hongyuan; Frank, Joachim; Lin, Qiao

2017-04-04

We describe a spraying-plunging method for preparing cryoelectron microscopy (cryo-EM) grids with vitreous ice of controllable, highly consistent thickness using a microfluidic device. The new polydimethylsiloxane (PDMS)-based sprayer was tested with apoferritin. We demonstrate that the structure can be solved to high resolution with this method of sample preparation. Besides replacing the conventional pipetting-blotting-plunging method, one of many potential applications of the new sprayer is in time-resolved cryo-EM, as part of a PDMS-based microfluidic reaction channel to study short-lived intermediates on the timescale of 10-1,000 ms. Published by Elsevier Ltd.

Annika Eberle | NREL

Science.gov Websites

analysis Life cycle assessment Fluid-structure interaction Bio-inspired materials and design Education and . Daniel. "Fluid-structure interaction in compliant insect wings." Bioinspiration and Biomimetics

Sandia National Laboratories: Up on the roof

Science.gov Websites

load of rooftop solar photovoltaic (PV) installations," says structural engineer Steve Dwyer (6912 deemed not strong enough. More load-bearing capacity In two, first-of-their-kind studies funded by DOE's load-bearing capacity for residential rooftop structural systems is several times higher than the

Materials Science Research | Materials Science | NREL

Science.gov Websites

Structure Theory We use high-performance computing to design and discover materials for energy, and to study structure of surfaces and critical interfaces. Images of red and yellow particles Materials Discovery Our by traditional targeted experiments. Photo of a stainless steel piece of equipment with multiple

Manufacture and characterisation of EmDerm-novel hierarchically structured bio-active scaffolds for tissue regeneration.

PubMed

Lim, Xuxin; Potter, Matthew; Cui, Zhanfeng; Dye, Julian F

2018-06-05

There are significant challenges for using emulsion templating as a method of manufacturing macro-porous protein scaffolds. Issues include protein denaturation by adsorption at hydrophobic interfaces, emulsion instability, oil droplet and surfactant removal after protein gelation, and compatible cross-linking methods. We investigated an oil-in-water macro-emulsion stabilised with a surfactant blend, as a template for manufacturing protein-based nano-structured bio-intelligent scaffolds (EmDerm) with tuneable micro-scale porosity for tissue regeneration. Prototype EmDerm scaffolds were made using either collagen, through thermal gelation, fibrin, through enzymatic coagulation or collagen-fibrin composite. Pore size was controlled via surfactant-to-oil phase ratio. Scaffolds were crosslink-stabilised with EDC/NHS for varying durations. Scaffold micro-architecture and porosity were characterised with SEM, and mechanical properties by tensiometry. Hydrolytic and proteolytic degradation profiles were quantified by mass decrease over time. Human dermal fibroblasts, endothelial cells and bone marrow derived mesenchymal stem cells were used to investigate cytotoxicity and cell proliferation within each scaffold. EmDerm scaffolds showed nano-scale based hierarchical structures, with mean pore diameters ranging from 40-100 microns. The Young's modulus range was 1.1-2.9 MPa, and ultimate tensile strength was 4-16 MPa. Degradation rate was related to cross-linking duration. Each EmDerm scaffold supported excellent cell ingress and proliferation compared to the reference materials Integra™ and Matriderm™. Emulsion templating is a novel rapid method of fabricating nano-structured fibrous protein scaffolds with micro-scale pore dimensions. These scaffolds hold promising clinical potential for regeneration of the dermis and other soft tissues, e.g., for burns or chronic wound therapies.

NREL Researchers Create New Materials With Unusual Properties | News | NREL

Science.gov Websites

show how such new low-density materials can be made - with unique properties remarkably different from compounds with atomic structures that didn't match, the researchers theorized that mixing two different high manganese telluride (MnTe) that have different crystal structures - the approach known as heterostructural

Publications - RI 2011-3B | Alaska Division of Geological & Geophysical

Science.gov Websites

structural cross sections for the Kavik River map area, Alaska Authors: Wallace, W.K., Wartes, M.A., Decker Kavik River map area, Alaska: Alaska Division of Geological & Geophysical Surveys Report of area, Alaska (144.0 M) Sheet 2 Interpretations of seismic reflection data and structural cross sections

Rick Damiani | NREL

Science.gov Websites

design and analysis of blades and support structures. Rick also supports various technical projects 15 years. He focuses on aeroelastic modeling of turbines and structural design and analysis of blades

Joint Chiefs of Staff > Media

Science.gov Websites

Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Media News Videos Chairman's

Argonne Physics Division

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, nuclear structure and reaction research, nuclear theory, medium energy nuclear research and accelerator structure of baryonic matter in the universe - the matter that makes up stars, planets and human life itself

Large-scale 3D inversion of marine controlled source electromagnetic data using the integral equation method

NASA Astrophysics Data System (ADS)

Zhdanov, M. S.; Cuma, M.; Black, N.; Wilson, G. A.

2009-12-01

The marine controlled source electromagnetic (MCSEM) method has become widely used in offshore oil and gas exploration. Interpretation of MCSEM data is still a very challenging problem, especially if one would like to take into account the realistic 3D structure of the subsurface. The inversion of MCSEM data is complicated by the fact that the EM response of a hydrocarbon-bearing reservoir is very weak in comparison with the background EM fields generated by an electric dipole transmitter in complex geoelectrical structures formed by a conductive sea-water layer and the terranes beneath it. In this paper, we present a review of the recent developments in the area of large-scale 3D EM forward modeling and inversion. Our approach is based on using a new integral form of Maxwell’s equations allowing for an inhomogeneous background conductivity, which results in a numerically effective integral representation for 3D EM field. This representation provides an efficient tool for the solution of 3D EM inverse problems. To obtain a robust inverse model of the conductivity distribution, we apply regularization based on a focusing stabilizing functional which allows for the recovery of models with both smooth and sharp geoelectrical boundaries. The method is implemented in a fully parallel computer code, which makes it possible to run large-scale 3D inversions on grids with millions of inversion cells. This new technique can be effectively used for active EM detection and monitoring of the subsurface targets.

The Joint Chiefs of Staff Video Collections

Science.gov Websites

Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Home : Media : Videos Featured Videos Gen

Maria Goeppert Mayer, the Nuclear Shell Structure, and Magic Numbers

Science.gov Websites

dropdown arrow Site Map A-Z Index Menu Synopsis Maria Goeppert-Mayer, the Nuclear Shell Model, and Magic explanation of how neutrons and protons within atomic nuclei are structured. Called the "nuclear shell American husband, chemical physicist Joseph Mayer. At Argonne, Goeppert-Mayer learned most of her nuclear

Improved cryoEM-Guided Iterative Molecular Dynamics–Rosetta Protein Structure Refinement Protocol for High Precision Protein Structure Prediction

PubMed Central

2016-01-01

Many excellent methods exist that incorporate cryo-electron microscopy (cryoEM) data to constrain computational protein structure prediction and refinement. Previously, it was shown that iteration of two such orthogonal sampling and scoring methods – Rosetta and molecular dynamics (MD) simulations – facilitated exploration of conformational space in principle. Here, we go beyond a proof-of-concept study and address significant remaining limitations of the iterative MD–Rosetta protein structure refinement protocol. Specifically, all parts of the iterative refinement protocol are now guided by medium-resolution cryoEM density maps, and previous knowledge about the native structure of the protein is no longer necessary. Models are identified solely based on score or simulation time. All four benchmark proteins showed substantial improvement through three rounds of the iterative refinement protocol. The best-scoring final models of two proteins had sub-Ångstrom RMSD to the native structure over residues in secondary structure elements. Molecular dynamics was most efficient in refining secondary structure elements and was thus highly complementary to the Rosetta refinement which is most powerful in refining side chains and loop regions. PMID:25883538

SynapticDB, effective web-based management and sharing of data from serial section electron microscopy.

PubMed

Shi, Bitao; Bourne, Jennifer; Harris, Kristen M

2011-03-01

Serial section electron microscopy (ssEM) is rapidly expanding as a primary tool to investigate synaptic circuitry and plasticity. The ultrastructural images collected through ssEM are content rich and their comprehensive analysis is beyond the capacity of an individual laboratory. Hence, sharing ultrastructural data is becoming crucial to visualize, analyze, and discover the structural basis of synaptic circuitry and function in the brain. We devised a web-based management system called SynapticDB (http://synapses.clm.utexas.edu/synapticdb/) that catalogues, extracts, analyzes, and shares experimental data from ssEM. The management strategy involves a library with check-in, checkout and experimental tracking mechanisms. We developed a series of spreadsheet templates (MS Excel, Open Office spreadsheet, etc) that guide users in methods of data collection, structural identification, and quantitative analysis through ssEM. SynapticDB provides flexible access to complete templates, or to individual columns with instructional headers that can be selected to create user-defined templates. New templates can also be generated and uploaded. Research progress is tracked via experimental note management and dynamic PDF forms that allow new investigators to follow standard protocols and experienced researchers to expand the range of data collected and shared. The combined use of templates and tracking notes ensures that the supporting experimental information is populated into the database and associated with the appropriate ssEM images and analyses. We anticipate that SynapticDB will serve future meta-analyses towards new discoveries about the composition and circuitry of neurons and glia, and new understanding about structural plasticity during development, behavior, learning, memory, and neuropathology.

Efficient EM Simulation of GCPW Structures Applied to a 200-GHz mHEMT Power Amplifier MMIC

NASA Astrophysics Data System (ADS)

Campos-Roca, Yolanda; Amado-Rey, Belén; Wagner, Sandrine; Leuther, Arnulf; Bangert, Axel; Gómez-Alcalá, Rafael; Tessmann, Axel

2017-05-01

The behaviour of grounded coplanar waveguide (GCPW) structures in the upper millimeter-wave range is analyzed by using full-wave electromagnetic (EM) simulations. A methodological approach to develop reliable and time-efficient simulations is proposed by investigating the impact of different simplifications in the EM modelling and simulation conditions. After experimental validation with measurements on test structures, this approach has been used to model the most critical passive structures involved in the layout of a state-of-the-art 200-GHz power amplifier based on metamorphic high electron mobility transistors (mHEMTs). This millimeter-wave monolithic integrated circuit (MMIC) has demonstrated a measured output power of 8.7 dBm for an input power of 0 dBm at 200 GHz. The measured output power density and power-added efficiency (PAE) are 46.3 mW/mm and 4.5 %, respectively. The peak measured small-signal gain is 12.7 dB (obtained at 196 GHz). A good agreement has been obtained between measurements and simulation results.

Protein secondary structure determination by constrained single-particle cryo-electron tomography.

PubMed

Bartesaghi, Alberto; Lecumberry, Federico; Sapiro, Guillermo; Subramaniam, Sriram

2012-12-05

Cryo-electron microscopy (cryo-EM) is a powerful technique for 3D structure determination of protein complexes by averaging information from individual molecular images. The resolutions that can be achieved with single-particle cryo-EM are frequently limited by inaccuracies in assigning molecular orientations based solely on 2D projection images. Tomographic data collection schemes, however, provide powerful constraints that can be used to more accurately determine molecular orientations necessary for 3D reconstruction. Here, we propose "constrained single-particle tomography" as a general strategy for 3D structure determination in cryo-EM. A key component of our approach is the effective use of images recorded in tilt series to extract high-resolution information and correct for the contrast transfer function. By incorporating geometric constraints into the refinement to improve orientational accuracy of images, we reduce model bias and overrefinement artifacts and demonstrate that protein structures can be determined at resolutions of ∼8 Å starting from low-dose tomographic tilt series. Copyright © 2012 Elsevier Ltd. All rights reserved.

Heterocyclic energetic materials: Synthesis, characterization and computational design

NASA Astrophysics Data System (ADS)

Tsyshevsky, Roman; Pagoria, Philip; Smirnov, Aleksander; Kuklja, Maija

2017-06-01

Achievement of the tailored properties (high performance, low sensitivity, etc.) in targeted new energetic materials (EM) remains a great challenge. Recently, attention of researchers has shifted from conventional nitroester-, nitramine-, and nitroaromatic-based explosives to new heterocyclic EM with oxygen- and nitrogenrich molecular structures. They have increased densities and formation enthalpies complemented by attractive performance and high stability to external stimuli. We will demonstrate that oxadiazol-containing heterocycles offer a convenient playground to probe specific chemical functional groups as building blocks for design of EM. We discuss a joint experimental and computational approach for design, characterization, synthesis, and modeling of novel heterocyclic EM. Combinatorically, we comprehensively analyzed how overall stability and performance of each material in the family (BNFF, LLM-172, LLM-175, LLM-191, LLM-192, LLM-200) depends upon their chemical composition and details of the molecular structure (such as a substitution of a nitro group by an amino group and 1,2,5-oxadiazole fragment by 1,2,3- or 1,2,4-oxadiazol ring). We will also discuss proposed new EM with predicted superior chemical and physical properties. P. Pagoria, R. Tsyshevsky, A. Smirnov.

Joint Chiefs of Staff > Directorates > J3 | Operations

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Joint Staff Structure Joint Staff Inspector General Origin of Joint Concepts U.S. Code | Joint Chiefs of J8 | Force Structure, Resources & Assessment Contact J3 Operations Home : Directorates : J3

Employee Spotlight: Clarence Chang | Argonne National Laboratory

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batteries --Electricity transmission --Smart Grid Environment -Biology --Computational biology --Environmental biology ---Metagenomics ---Terrestrial ecology --Molecular biology ---Clinical proteomics and biomarker discovery ---Interventional biology ---Proteomics --Structural biology -Environmental science &

Delivery of femtolitre droplets using surface acoustic wave based atomisation for cryo-EM grid preparation.

PubMed

Ashtiani, Dariush; Venugopal, Hari; Belousoff, Matthew; Spicer, Bradley; Mak, Johnson; Neild, Adrian; de Marco, Alex

2018-04-06

Cryo-Electron Microscopy (cryo-EM) has become an invaluable tool for structural biology. Over the past decade, the advent of direct electron detectors and automated data acquisition has established cryo-EM as a central method in structural biology. However, challenges remain in the reliable and efficient preparation of samples in a manner which is compatible with high time resolution. The delivery of sample onto the grid is recognized as a critical step in the workflow as it is a source of variability and loss of material due to the blotting which is usually required. Here, we present a method for sample delivery and plunge freezing based on the use of Surface Acoustic Waves to deploy 6-8 µm droplets to the EM grid. This method minimises the sample dead volume and ensures vitrification within 52.6 ms from the moment the sample leaves the microfluidics chip. We demonstrate a working protocol to minimize the atomised volume and apply it to plunge freeze three different samples and provide proof that no damage occurs due to the interaction between the sample and the acoustic waves. Copyright © 2018 Elsevier Inc. All rights reserved.

Seismoelectric Effects based on Spectral-Element Method for Subsurface Fluid Characterization

NASA Astrophysics Data System (ADS)

Morency, C.

2017-12-01

Present approaches for subsurface imaging rely predominantly on seismic techniques, which alone do not capture fluid properties and related mechanisms. On the other hand, electromagnetic (EM) measurements add constraints on the fluid phase through electrical conductivity and permeability, but EM signals alone do not offer information of the solid structural properties. In the recent years, there have been many efforts to combine both seismic and EM data for exploration geophysics. The most popular approach is based on joint inversion of seismic and EM data, as decoupled phenomena, missing out the coupled nature of seismic and EM phenomena such as seismoeletric effects. Seismoelectric effects are related to pore fluid movements with respect to the solid grains. By analyzing coupled poroelastic seismic and EM signals, one can capture a pore scale behavior and access both structural and fluid properties.Here, we model the seismoelectric response by solving the governing equations derived by Pride and Garambois (1994), which correspond to Biot's poroelastic wave equations and Maxwell's electromagnetic wave equations coupled electrokinetically. We will show that these coupled wave equations can be numerically implemented by taking advantage of viscoelastic-electromagnetic mathematical equivalences. These equations will be solved using a spectral-element method (SEM). The SEM, in contrast to finite-element methods (FEM) uses high degree Lagrange polynomials. Not only does this allow the technique to handle complex geometries similarly to FEM, but it also retains exponential convergence and accuracy due to the use of high degree polynomials. Finally, we will discuss how this is a first step toward full coupled seismic-EM inversion to improve subsurface fluid characterization. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Ensemble cryoEM elucidates the mechanism of insulin capture and degradation by human insulin degrading enzyme

PubMed Central

Bailey, Lucas J; Tan, Yong Zi; Wei, Hui; Wang, Andrew; Farcasanu, Mara; Woods, Virgil A; McCord, Lauren A; Lee, David; Shang, Weifeng; Deprez-Poulain, Rebecca; Deprez, Benoit; Liu, David R; Koide, Akiko; Koide, Shohei; Kossiakoff, Anthony A

2018-01-01

Insulin degrading enzyme (IDE) plays key roles in degrading peptides vital in type two diabetes, Alzheimer's, inflammation, and other human diseases. However, the process through which IDE recognizes peptides that tend to form amyloid fibrils remained unsolved. We used cryoEM to understand both the apo- and insulin-bound dimeric IDE states, revealing that IDE displays a large opening between the homologous ~55 kDa N- and C-terminal halves to allow selective substrate capture based on size and charge complementarity. We also used cryoEM, X-ray crystallography, SAXS, and HDX-MS to elucidate the molecular basis of how amyloidogenic peptides stabilize the disordered IDE catalytic cleft, thereby inducing selective degradation by substrate-assisted catalysis. Furthermore, our insulin-bound IDE structures explain how IDE processively degrades insulin by stochastically cutting either chain without breaking disulfide bonds. Together, our studies provide a mechanism for how IDE selectively degrades amyloidogenic peptides and offers structural insights for developing IDE-based therapies. PMID:29596046

Effect of potent endomorphin degradation blockers on analgesic and antidepressant-like responses in mice.

PubMed

Cravezic, Aurore; Fichna, Jakub; Gach, Katarzyna; Wyrebska, Anna; Perlikowska, Renata; Costentin, Jean; Bonnet, Jean-Jacques; Janecka, Anna; do Rego, Jean-Claude

2011-12-01

The biological effects of endomorphins (EMs) are short-lasting due to their rapid degradation by endogenous enzymes. Competing enzymatic degradation is an approach to prolong EM bioavailability. In the present study, a series of tetra- and tripeptides of similar to EMs structure was synthesized and tested in vitro and in vivo for their ability to inhibit degradation of EMs. The obtained results indicated that, among the series of analogs, the tetrapeptide Tyr-Pro-d-ClPhe-Phe-NH(2) and the tripeptide Tyr-Pro-Ala-NH(2), which did not bind to the μ-opioid receptors, were potent inhibitors of EM catabolism in rat brain homogenate. In vivo, these two peptides significantly prolonged the analgesic and antidepressant-like effects, induced by exogenous EMs, by blocking EM degrading enzymes. These new potent inhibitors may therefore increase the level and the half life of endogenous EMs and could be used in a new therapeutic strategy against pain and mood disorders, based on increasing of EM bioavailability. Copyright © 2011 Elsevier Ltd. All rights reserved.

Michael Sprague | NREL

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student, he developed a parallel spectral finite element method for treating the interaction of large mechanics of fluids, structures, and their interaction|Spectral finite-element methods for time-dependent

Ahmad Mayyas | NREL

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University-International Center for Automotive Research (CU-ICAR) (2009-2012) Intern/Reliability Engineer selection for body-in-white." International Journal of Sustainable Manufacturing 2, no. 4 (August 2012 Structure Case Study." Accepted for publication in International Journal of Sustainable Engineering

Medical Image Fusion Based on Feature Extraction and Sparse Representation

PubMed Central

Wei, Gao; Zongxi, Song

2017-01-01

As a novel multiscale geometric analysis tool, sparse representation has shown many advantages over the conventional image representation methods. However, the standard sparse representation does not take intrinsic structure and its time complexity into consideration. In this paper, a new fusion mechanism for multimodal medical images based on sparse representation and decision map is proposed to deal with these problems simultaneously. Three decision maps are designed including structure information map (SM) and energy information map (EM) as well as structure and energy map (SEM) to make the results reserve more energy and edge information. SM contains the local structure feature captured by the Laplacian of a Gaussian (LOG) and EM contains the energy and energy distribution feature detected by the mean square deviation. The decision map is added to the normal sparse representation based method to improve the speed of the algorithm. Proposed approach also improves the quality of the fused results by enhancing the contrast and reserving more structure and energy information from the source images. The experiment results of 36 groups of CT/MR, MR-T1/MR-T2, and CT/PET images demonstrate that the method based on SR and SEM outperforms five state-of-the-art methods. PMID:28321246

Concentrating Solar Power Projects - Dish/Engine Projects | Concentrating

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together to form a dish-shaped structure. The receiver is supported above the panels by an arm-like structure and glows as it is heated by concentrated sunlight. A technician sits below the dish, in the shade

Multiscale Modeling of Plasmon-Enhanced Power Conversion Efficiency in Nanostructured Solar Cells.

PubMed

Meng, Lingyi; Yam, ChiYung; Zhang, Yu; Wang, Rulin; Chen, GuanHua

2015-11-05

The unique optical properties of nanometallic structures can be exploited to confine light at subwavelength scales. This excellent light trapping is critical to improve light absorption efficiency in nanoscale photovoltaic devices. Here, we apply a multiscale quantum mechanics/electromagnetics (QM/EM) method to model the current-voltage characteristics and optical properties of plasmonic nanowire-based solar cells. The QM/EM method features a combination of first-principles quantum mechanical treatment of the photoactive component and classical description of electromagnetic environment. The coupled optical-electrical QM/EM simulations demonstrate a dramatic enhancement for power conversion efficiency of nanowire solar cells due to the surface plasmon effect of nanometallic structures. The improvement is attributed to the enhanced scattering of light into the photoactive layer. We further investigate the optimal configuration of the nanostructured solar cell. Our QM/EM simulation result demonstrates that a further increase of internal quantum efficiency can be achieved by scattering light into the n-doped region of the device.

Structured inspection of medications carried and stored by emergency medical services agencies identifies practices that may lead to medication errors.

PubMed

Kupas, Douglas F; Shayhorn, Meghan A; Green, Paul; Payton, Thomas F

2012-01-01

Medications are essential to emergency medical services (EMS) agencies when providing lifesaving care, but the EMS environment has challenges related to safe medication storage when compared with a hospital setting. We developed a structured process, based on common pharmacy practices, to review medications carried by EMS agencies to identify situations that may lead to medication error and to determine some best practices that may reduce potential errors and the risk of patient harm. To provide a descriptive account of EMS practices related to carrying and storing medications that have the potential for causing a medication administration error or patient harm. Using a structured process for inspection, an emergency medicine pharmacist and emergency physician(s) reviewed the medication carrying and storage practices of all nine advanced life support ambulance agencies within a five-county EMS region. Each medication carried and stored by the EMS agency was inspected for predetermined and spontaneously observed issues that could lead to medication error. These issues were documented and photographed. Two EMS medical directors reviewed each potential error for the risk of producing patient harm and assigned each to a category of high, moderate, or low risk. Because issues of temperature on EMS medications have been addressed elsewhere, this study concentrated on potential for EMS medication administration errors exclusive of storage temperatures. When reviewing medications carried by the nine EMS agencies, 38 medication safety issues were identified (range 1 to 8 per EMS agency). Of these, 16 were considered to be high risk, 14 moderate risk, and eight low risk for patient harm. Examples of potential issues included carrying expired medications, container-labeling issues, different medications stored in look-alike vials or prefilled syringes in the same compartment, and carrying crystalloid solutions next to solutions premixed with a medication. When reviewing medications stored at the EMS agency stations, eight safety issues were identified (range from 0 to 4 per station), including five moderate-risk and three low-risk issues. No agency had any high-risk medication issues related to storage of medication stock in the station. We observed potential medication safety issues related to how medications are carried and stored at all nine EMS agencies in a five-county region. Understanding these issues may assist EMS agencies in reducing the potential for a medication error and risk of patient harm. More research is needed to determine whether following these suggested best practices for carrying medications on EMS vehicles actually reduces errors in medication administration by EMS providers or decreases patient harm.

Broadband asymmetric transmission of linearly polarized electromagnetic waves based on chiral metamaterial

NASA Astrophysics Data System (ADS)

Stephen, Lincy; Yogesh, N.; Subramanian, V.

2018-01-01

The giant optical activity of chiral metamaterials (CMMs) holds great potential for tailoring the polarization state of an electromagnetic (EM) wave. In controlling the polarization state, the aspect of asymmetric transmission (AT), where a medium allows the EM radiation to pass through in one direction while restricting it in the opposite direction, adds additional degrees of freedom such as one-way channelling functionality. In this work, a CMM formed by a pair of mutually twisted slanted complementary metal strips is realized for broadband AT accompanied with cross-polarization (CP) conversion for linearly polarized EM waves. Numerically, the proposed ultra-thin (˜λ/42) CMM shows broadband AT from 8.58 GHz to 9.73 GHz (bandwidth of 1.15 GHz) accompanied with CP transmission magnitude greater than 0.9. The transmission and reflection spectra reveal the origin of the asymmetric transmission as the direction sensitive cross polarization conversion and anisotropic electric coupling occurring in the structure which is then elaborated with the surface current analysis and electric field distribution within the structure. An experiment is carried out to verify the broadband AT based CP conversion of the proposed CMM at microwave frequencies, and a reliable agreement between numerical and experimental results is obtained. Being ultra-thin, the reported broadband AT based CP conversion of the proposed CMM is useful for controlling radiation patterns in non-reciprocal EM devices and communication networks.

Cryo-EM visualization of the protein machine that replicates the chromosome

NASA Astrophysics Data System (ADS)

Li, Huilin

Structural knowledge is key to understanding biological functions. Cryo-EM is a physical method that uses transmission electron microscopy to visualize biological molecules that are frozen in vitreous ice. Due to recent advances in direct electron detector and image processing algorithm, cryo-EM has become a high-resolution technique. Cryo-EM field is undergoing a rapid expansion and vast majority research institutions and research universities around the world are setting up cryo-EM research. Indeed, the method is revolutionizing structural and molecular biology. We have been using cryo-EM to study the structure and mechanism of eukaryotic chromosome replication. Despite an abundance of cartoon drawings found in review articles and biology textbooks, the structure of the eukaryotic helicase that unwinds the double stranded DNA has been unknown. It has also been unknown how the helicase works with DNA polymerases to accomplish the feat of duplicating the genome. In my presentation, I will show how we have used cryo-EM to derive at structures of the eukaryotic chromosome replication machinery and describe mechanistic insights we have gleaned from the structures.

Bryon S. Donohoe, Ph.D | NREL

Science.gov Websites

structural biology and plant/algal cell biology to address questions about the cellular mechanisms involved Biology, University of Colorado at Boulder M.A., Biology, University of Colorado at Denver B.S

Presentations - Herriott, T.M. and others, 2011 | Alaska Division of

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Details Title: Detailed geologic mapping and overview of structural and stratigraphic studies in the east Resident Business in Alaska Visiting Alaska State Employees DGGS State of Alaska search Alaska Division of in the east-central North Slope foothills, Alaska (poster): 3P Arctic, The Polar Petroleum Potential

SSRL HEADLINES April 2018

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and x-ray spectroscopy pioneer, Farrel W. Lytle, and include precious metals such as gold, silver structure of matter called x-ray absorption spectroscopy. The foils were donated by entrepreneur, scientist activities on x-ray fluorescence imaging in ancient materials like fossils and the Archimedes Palimpsest

Live CLEM imaging to analyze nuclear structures at high resolution.

PubMed

Haraguchi, Tokuko; Osakada, Hiroko; Koujin, Takako

2015-01-01

Fluorescence microscopy (FM) and electron microscopy (EM) are powerful tools for observing molecular components in cells. FM can provide temporal information about cellular proteins and structures in living cells. EM provides nanometer resolution images of cellular structures in fixed cells. We have combined FM and EM to develop a new method of correlative light and electron microscopy (CLEM), called "Live CLEM." In this method, the dynamic behavior of specific molecules of interest is first observed in living cells using fluorescence microscopy (FM) and then cellular structures in the same cell are observed using electron microscopy (EM). Following image acquisition, FM and EM images are compared to enable the fluorescent images to be correlated with the high-resolution images of cellular structures obtained using EM. As this method enables analysis of dynamic events involving specific molecules of interest in the context of specific cellular structures at high resolution, it is useful for the study of nuclear structures including nuclear bodies. Here we describe Live CLEM that can be applied to the study of nuclear structures in mammalian cells.

Model Documentation of Base Case Data | Regional Energy Deployment System

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Model | Energy Analysis | NREL Documentation of Base Case Data Model Documentation of Base Case base case of the model. The base case was developed simply as a point of departure for other analyses Base Case derives many of its inputs from the Energy Information Administration's (EIA's) Annual Energy

Press Release | News | Page 2

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: Attend a Dark Matter Day event October 23, 2017 The world will soon be celebrating the hunt for the universe's most elusive matter in a series of Dark Matter Day events planned in over a dozen countries reveals most accurate measurement of dark matter structure in the universe August 3, 2017 Dark Energy

Orion EM-1 Crew Module Structural Test Article Move to Birdcage

NASA Image and Video Library

2016-11-16

Inside the Neil Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida, Lockheed Martin technicians monitor the progress as a crane begins to lift the Orion crew module structural test article (STA) up from the base of its transport container. The STA arrived aboard NASA's Super Guppy aircraft at the Shuttle Landing Facility operated by Space Florida. The test article will be moved to a test tool called the birdcage for further testing. The Orion spacecraft will launch atop NASA’s Space Launch System rocket on EM-1, its first deep space mission, in late 2018.

Orion EM-1 Crew Module Structural Test Article Move to Birdcage

NASA Image and Video Library

2016-11-16

Inside the Neil Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida, Lockheed Martin technicians monitor the progress as a crane lifts the Orion crew module structural test article (STA) up from the base of its transport container. The STA arrived aboard NASA's Super Guppy aircraft at the Shuttle Landing Facility operated by Space Florida. The test article will be moved to a test tool called the birdcage for further testing. The Orion spacecraft will launch atop NASA’s Space Launch System rocket on EM-1, its first deep space mission, in late 2018.

Orion EM-1 Crew Module Structural Test Article Move to Birdcage

NASA Image and Video Library

2016-11-16

Inside the Neil Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida, Lockheed Martin technicians monitor the progress as a crane lifts the Orion crew module structural test article (STA) away from the base of its transport container. The STA arrived aboard NASA's Super Guppy aircraft at the Shuttle Landing Facility operated by Space Florida. The test article will be moved to a test tool called the birdcage for further testing. The Orion spacecraft will launch atop NASA’s Space Launch System rocket on EM-1, its first deep space mission, in late 2018.

Matt Churchfield | NREL

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focuses on high-fidelity simulation of wind plant aerodynamics using large-eddy simulation. Particularly Applications (SOWFA), a coupled fluid-structure-controls simulation tool specifically for wind plants. Matt's

Events | Pacific Earthquake Engineering Research Center

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home about peer news events research products laboratories publications nisee b.i.p. members education FAQs links Events Calendar of PEER and Other Events PEER Events Archive PEER Annual Meeting 2009 Experimental Structural Engineering PEER Summative Meeting Site Map Search Calendar of PEER and Other Events

Viewing Angle Classification of Cryo-Electron Microscopy Images Using Eigenvectors

PubMed Central

Singer, A.; Zhao, Z.; Shkolnisky, Y.; Hadani, R.

2012-01-01

The cryo-electron microscopy (cryo-EM) reconstruction problem is to find the three-dimensional structure of a macromolecule given noisy versions of its two-dimensional projection images at unknown random directions. We introduce a new algorithm for identifying noisy cryo-EM images of nearby viewing angles. This identification is an important first step in three-dimensional structure determination of macromolecules from cryo-EM, because once identified, these images can be rotationally aligned and averaged to produce “class averages” of better quality. The main advantage of our algorithm is its extreme robustness to noise. The algorithm is also very efficient in terms of running time and memory requirements, because it is based on the computation of the top few eigenvectors of a specially designed sparse Hermitian matrix. These advantages are demonstrated in numerous numerical experiments. PMID:22506089

3DIANA: 3D Domain Interaction Analysis: A Toolbox for Quaternary Structure Modeling

PubMed Central

Segura, Joan; Sanchez-Garcia, Ruben; Tabas-Madrid, Daniel; Cuenca-Alba, Jesus; Sorzano, Carlos Oscar S.; Carazo, Jose Maria

2016-01-01

Electron microscopy (EM) is experiencing a revolution with the advent of a new generation of Direct Electron Detectors, enabling a broad range of large and flexible structures to be resolved well below 1 nm resolution. Although EM techniques are evolving to the point of directly obtaining structural data at near-atomic resolution, for many molecules the attainable resolution might not be enough to propose high-resolution structural models. However, accessing information on atomic coordinates is a necessary step toward a deeper understanding of the molecular mechanisms that allow proteins to perform specific tasks. For that reason, methods for the integration of EM three-dimensional maps with x-ray and NMR structural data are being developed, a modeling task that is normally referred to as fitting, resulting in the so called hybrid models. In this work, we present a novel application—3DIANA—specially targeted to those cases in which the EM map resolution is medium or low and additional experimental structural information is scarce or even lacking. In this way, 3DIANA statistically evaluates proposed/potential contacts between protein domains, presents a complete catalog of both structurally resolved and predicted interacting regions involving these domains and, finally, suggests structural templates to model the interaction between them. The evaluation of the proposed interactions is computed with DIMERO, a new method that scores physical binding sites based on the topology of protein interaction networks, which has recently shown the capability to increase by 200% the number of domain-domain interactions predicted in interactomes as compared to previous approaches. The new application displays the information at a sequence and structural level and is accessible through a web browser or as a Chimera plugin at http://3diana.cnb.csic.es. PMID:26772592

Sequential computation of elementary modes and minimal cut sets in genome-scale metabolic networks using alternate integer linear programming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Hyun-Seob; Goldberg, Noam; Mahajan, Ashutosh

Elementary (flux) modes (EMs) have served as a valuable tool for investigating structural and functional properties of metabolic networks. Identification of the full set of EMs in genome-scale networks remains challenging due to combinatorial explosion of EMs in complex networks. It is often, however, that only a small subset of relevant EMs needs to be known, for which optimization-based sequential computation is a useful alternative. Most of the currently available methods along this line are based on the iterative use of mixed integer linear programming (MILP), the effectiveness of which significantly deteriorates as the number of iterations builds up. Tomore » alleviate the computational burden associated with the MILP implementation, we here present a novel optimization algorithm termed alternate integer linear programming (AILP). Results: Our algorithm was designed to iteratively solve a pair of integer programming (IP) and linear programming (LP) to compute EMs in a sequential manner. In each step, the IP identifies a minimal subset of reactions, the deletion of which disables all previously identified EMs. Thus, a subsequent LP solution subject to this reaction deletion constraint becomes a distinct EM. In cases where no feasible LP solution is available, IP-derived reaction deletion sets represent minimal cut sets (MCSs). Despite the additional computation of MCSs, AILP achieved significant time reduction in computing EMs by orders of magnitude. The proposed AILP algorithm not only offers a computational advantage in the EM analysis of genome-scale networks, but also improves the understanding of the linkage between EMs and MCSs.« less

X-ray structure determination using low-resolution electron microscopy maps for molecular replacement

DOE PAGES

Jackson, Ryan N.; McCoy, Airlie J.; Terwilliger, Thomas C.; ...

2015-07-30

Structures of multi-subunit macromolecular machines are primarily determined by either electron microscopy (EM) or X-ray crystallography. In many cases, a structure for a complex can be obtained at low resolution (at a coarse level of detail) with EM and at higher resolution (with finer detail) by X-ray crystallography. The integration of these two structural techniques is becoming increasingly important for generating atomic models of macromolecular complexes. A low-resolution EM image can be a powerful tool for obtaining the "phase" information that is missing from an X-ray crystallography experiment, however integration of EM and X-ray diffraction data has been technically challenging.more » Here we show a step-by-step protocol that explains how low-resolution EM maps can be placed in the crystallographic unit cell by molecular replacement, and how initial phases computed from the placed EM density are extended to high resolution by averaging maps over non-crystallographic symmetry. As the resolution gap between EM and Xray crystallography continues to narrow, the use of EM maps to help with X-ray crystal structure determination, as described in this protocol, will become increasingly effective.« less

Seonah Kim, Ph.D. | NREL

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lignocellulosic biomass enzymes Design of new catalysts for vapor phase upgrading of biomass pyrolysis Enzymatic Engineering for Continuous Hydrocarbon Fuel Production (PI) Computational Pyrolysis Consortium Zeolite design Celluase enzyme structure-function relationships to design enhanced cellulose systems Catalyst

Contact Us

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J8 | Force Structure, Resources & Assessment Contact Home : Contact Chairman's Social Media Chairman's Flicker Chairman's Blog SEAC's Social Media SEAC's Facebook SEAC's Flicker SEAC's Twitter Joint Staff's Social Media Joint Staff's Facebook Joint Staff's Flicker Joint Staff 's Twitter Social Media

Virtual Frog Dissection: Interactive 3D Graphics Via the Web

Science.gov Websites

Kit''. A student using this kit has the ability to view various parts of a frog from many different angles, and with the different anatomical structures visible or invisible. For example, the student can up to 60 kilobytes for high quality. Clicking on the image yields different results depending on how

Intensive Care Unit Structure Variation and Implications for Early Mobilization Practices. An International Survey.

PubMed

Bakhru, Rita N; McWilliams, David J; Wiebe, Douglas J; Spuhler, Vicki J; Schweickert, William D

2016-09-01

Early mobilization (EM) improves outcomes for mechanically ventilated patients. Variation in structure and organizational characteristics may affect implementation of EM practices. We queried intensive care unit (ICU) environment and standardized ICU practices to evaluate organizational characteristics that enable EM practice. We recruited 151 ICUs in France, 150 in Germany, 150 in the United Kingdom, and 500 in the United States by telephone. Survey domains included respondent characteristics, hospital and ICU characteristics, and ICU practices and protocols. We surveyed 1,484 ICU leaders and received a 64% response rate (951 ICUs). Eighty-eight percent of respondents were in nursing leadership roles; the remainder were physiotherapists. Surveyed ICUs were predominantly mixed medical-surgical units (67%), and 27% were medical ICUs. ICU staffing models differed significantly (P < 0.001 each) by country for high-intensity staffing, nurse/patient ratios, and dedicated physiotherapists. ICU practices differed by country, with EM practices present in 40% of French ICUs, 59% of German ICUs, 52% of U.K. ICUs, and 45% of U.S. ICUs. Formal written EM protocols were present in 24%, 30%, 20%, and 30%, respectively, of those countries' ICUs. In multivariate analysis, EM practice was associated with multidisciplinary rounds (odds ratio [OR], 1.77; P = 0.001), setting daily goals for patients (OR, 1.62; P = 0.02), presence of a dedicated physiotherapist (OR, 2.48; P < 0.001), and the ICU's being located in Germany (reference, United States; OR, 2.84; P < 0.001). EM practice was also associated with higher nurse staffing levels (1:1 nurse/patient ratio as a reference; 1:2 nurse/patient ratio OR, 0.59; P = 0.05; 1:3 nurse/patient ratio OR, 0.33; P = 0.005; 1:4 or less nurse/patient ratio OR, 0.37; P = 0.005). Those responding rarely cited ambulation of mechanically ventilated patients, use of a bedside cycle, or neuromuscular electrical stimulation as part of their EM practice. Physical therapy initiation, barriers to EM practice, and EM equipment were highly variable among respondents. International ICU structure and practice is quite heterogeneous, and several factors (multidisciplinary rounds, setting daily goals for patients, presence of a dedicated physiotherapist, country, and nurse/patient staffing ratio) are significantly associated with the practice of EM. Practice and barriers may be far different based upon staffing structure. To achieve successful implementation, whether through trials or quality improvement, ICU staffing and practice patterns must be taken into account.

NNDC Databases

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radiation. It includes an interactive chart of nuclides and a level plotting tool. XUNDL Experimental Unevaluated Nuclear Data List Experimental nuclear structure and decay data, covering more than 2,500 recent parameters* Retrieved information CSISRS alias EXFOR Nuclear reaction experimental data Experimental nuclear

Using structural damage statistics to derive macroseismic intensity within the Kathmandu valley for the 2015 M7.8 Gorkha, Nepal earthquake

NASA Astrophysics Data System (ADS)

McGowan, S. M.; Jaiswal, K. S.; Wald, D. J.

2017-09-01

We make and analyze structural damage observations from within the Kathmandu valley following the 2015 M7.8 Gorkha, Nepal earthquake to derive macroseismic intensities at several locations including some located near ground motion recording sites. The macroseismic intensity estimates supplement the limited strong ground motion data in order to characterize the damage statistics. This augmentation allows for direct comparisons between ground motion amplitudes and structural damage characteristics and ultimately produces a more constrained ground shaking hazard map for the Gorkha earthquake. For systematic assessments, we focused on damage to three specific building categories: (a) low/mid-rise reinforced concrete frames with infill brick walls, (b) unreinforced brick masonry bearing walls with reinforced concrete slabs, and (c) unreinforced brick masonry bearing walls with partial timber framing. Evaluating dozens of photos of each construction type, assigning each building in the study sample to a European Macroseismic Scale (EMS)-98 Vulnerability Class based upon its structural characteristics, and then individually assigning an EMS-98 Damage Grade to each building allows a statistically derived estimate of macroseismic intensity for each of nine study areas in and around the Kathmandu valley. This analysis concludes that EMS-98 macroseismic intensities for the study areas from the Gorkha mainshock typically were in the VII-IX range. The intensity assignment process described is more rigorous than the informal approach of assigning intensities based upon anecdotal media or first-person accounts of felt-reports, shaking, and their interpretation of damage. Detailed EMS-98 macroseismic assessments in urban areas are critical for quantifying relations between shaking and damage as well as for calibrating loss estimates. We show that the macroseismic assignments made herein result in fatality estimates consistent with the overall and district-wide reported values.

Using structural damage statistics to derive macroseismic intensity within the Kathmandu valley for the 2015 M7.8 Gorkha, Nepal earthquake

USGS Publications Warehouse

McGowan, Sean; Jaiswal, Kishor; Wald, David J.

2017-01-01

We make and analyze structural damage observations from within the Kathmandu valley following the 2015 M7.8 Gorkha, Nepal earthquake to derive macroseismic intensities at several locations including some located near ground motion recording sites. The macroseismic intensity estimates supplement the limited strong ground motion data in order to characterize the damage statistics. This augmentation allows for direct comparisons between ground motion amplitudes and structural damage characteristics and ultimately produces a more constrained ground shaking hazard map for the Gorkha earthquake. For systematic assessments, we focused on damage to three specific building categories: (a) low/mid-rise reinforced concrete frames with infill brick walls, (b) unreinforced brick masonry bearing walls with reinforced concrete slabs, and (c) unreinforced brick masonry bearing walls with partial timber framing. Evaluating dozens of photos of each construction type, assigning each building in the study sample to a European Macroseismic Scale (EMS)-98 Vulnerability Class based upon its structural characteristics, and then individually assigning an EMS-98 Damage Grade to each building allows a statistically derived estimate of macroseismic intensity for each of nine study areas in and around the Kathmandu valley. This analysis concludes that EMS-98 macroseismic intensities for the study areas from the Gorkha mainshock typically were in the VII–IX range. The intensity assignment process described is more rigorous than the informal approach of assigning intensities based upon anecdotal media or first-person accounts of felt-reports, shaking, and their interpretation of damage. Detailed EMS-98 macroseismic assessments in urban areas are critical for quantifying relations between shaking and damage as well as for calibrating loss estimates. We show that the macroseismic assignments made herein result in fatality estimates consistent with the overall and district-wide reported values.

Joint Chiefs of Staff > Directorates > Directorates of Management

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establishes information management requirements and manages the corporate Joint Staff decision process to Force Chief of Staff Chief of National Guard Bureau Biographies Directorates Directorates of Management J8 | Force Structure, Resources & Assessment Contact Directorate of Management Home

Energy Efficiency on Parade

Science.gov Websites

heating, ventilation and air conditioning (HVAC) systems, structural insulated panels to improve products and systems. NREL building engineers estimate the combination of advanced products and design Building America program manager George James. "All of the technologies and systems used in this house

Systematic investigations on fused π-system compounds of seven benzene rings prepared by photocyclization of diphenanthrylethenes.

PubMed

Fujino, Shota; Yamaji, Minoru; Okamoto, Hideki; Mutai, Toshiki; Yoshikawa, Isao; Houjou, Hirohiko; Tani, Fumito

2017-06-14

We studied the photoproducts of 1-(n-phenanthryl)-2-(m-phenanthryl)ethenes (nEm; n, m = 1, 3 and 9) for understanding photocyclization patterns based on NMR spectroscopy. The crystal structures of the photoproducts were analyzed by X-ray crystallography, and the photophysical features of the photocyclized molecules were investigated based on emission and transient absorption measurements. Phenanthrene derivatives substituted at the 1- and 3-positions were prepared for synthesizing nEm by photocyclization of stilbene derivatives. We obtained four types of primary photoproducts (n@m) from the corresponding nEm. Two of them were found to have racemic molecular structures in the single crystal determined by X-ray crystallography. Besides the primary photoproducts, two types of secondary photoproducts (n@mPP) were isolated. Fluorescence quantum yields and lifetimes of the obtained photoproducts were determined in solution whereas the definite fluorescence quantum yields were obtained in the powder. Observation of the triplet-triplet absorption spectra in solution by laser photolysis techniques showed that intersystem crossing to the triplet state competes with the fluorescence process.

Derek Vigil-Fowler | NREL

Science.gov Websites

simulation methods for materials physics and chemistry, with particular expertise in post-DFT, high accuracy methods such as the GW approximation for electronic structure and random phase approximation (RPA) total the art in computational methods, including efficient methods for including the effects of substrates

Wisconsin H-Alpha Mapper | UW-Madison Astronomy

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Department of Astronomy Wisconsin H-Alpha Mapper Overview Description About WHAM Fabry-Perot Spectroscopy National Science Foundation Astronomy and... 02.20.2012 | Continue Reading » WHAM featured at Natural Astronomy Galactic Structure GALFA GLIMPSE GLIMPSE360 WHAM Extragalactic Astronomy & Cosmology Local

Cornell Center for Materials Research - An NSF MRSEC

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Cornell Center for Materials Research Cornell Center for Materials Research | An NSF MRSEC Search Research Atomic Membranes for 3D Systems Structured Materials for Strong Light-Matter Interactions Mechanisms, Materials, and Devices for Spin Manipulation Seed Projects - Exploratory Research Acknowledging

Understanding a reference-free impedance method using collocated piezoelectric transducers

NASA Astrophysics Data System (ADS)

Kim, Eun Jin; Kim, Min Koo; Sohn, Hoon; Park, Hyun Woo

2010-03-01

A new concept of a reference-free impedance method, which does not require direct comparison with a baseline impedance signal, is proposed for damage detection in a plate-like structure. A single pair of piezoelectric (PZT) wafers collocated on both surfaces of a plate are utilized for extracting electro-mechanical signatures (EMS) associated with mode conversion due to damage. A numerical simulation is conducted to investigate the EMS of collocated PZT wafers in the frequency domain at the presence of damage through spectral element analysis. Then, the EMS due to mode conversion induced by damage are extracted using the signal decomposition technique based on the polarization characteristics of the collocated PZT wafers. The effects of the size and the location of damage on the decomposed EMS are investigated as well. Finally, the applicability of the decomposed EMS to the reference-free damage diagnosis is discussed.

X-rays in the Cryo-EM Era: Structural Biology’s Dynamic Future

PubMed Central

Shoemaker, Susannah C.; Ando, Nozomi

2018-01-01

Over the past several years, single-particle cryo-electron microscopy (cryo-EM) has emerged as a leading method for elucidating macromolecular structures at near-atomic resolution, rivaling even the established technique of X-ray crystallography. Cryo-EM is now able to probe proteins as small as hemoglobin (64 kDa), while avoiding the crystallization bottleneck entirely. The remarkable success of cryo-EM has called into question the continuing relevance of X-ray methods, particularly crystallography. To say that the future of structural biology is either cryo-EM or crystallography, however, would be misguided. Crystallography remains better suited to yield precise atomic coordinates of macromolecules under a few hundred kDa in size, while the ability to probe larger, potentially more disordered assemblies is a distinct advantage of cryo-EM. Likewise, crystallography is better equipped to provide high-resolution dynamic information as a function of time, temperature, pressure, and other perturbations, whereas cryo-EM offers increasing insight into conformational and energy landscapes, particularly as algorithms to deconvolute conformational heterogeneity become more advanced. Ultimately, the future of both techniques depends on how their individual strengths are utilized to tackle questions on the frontiers of structural biology. Structure determination is just one piece of a much larger puzzle: a central challenge of modern structural biology is to relate structural information to biological function. In this perspective, we share insight from several leaders in the field and examine the unique and complementary ways in which X-ray methods and cryo-EM can shape the future of structural biology. PMID:29227642

David K. Johnson | NREL

Science.gov Websites

analysis Lignin chemistry High-temperature and pressure lignin hydrotreating Catalytic hydrodeoxygenation ;Effects of alkaline or liquid-ammonia treatment on crystalline cellulose: changes in crystalline structure and effects on enzymatic digestibility," Biotechnology for Biofuels (2011) "Glucose

Laboratories | NREL

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| Z A Accelerated Exposure Testing Laboratory Advanced Optical Materials Laboratory Advanced Thermal Laboratory Structural Testing Laboratory Surface Analysis Laboratory Systems Performance Laboratory T Thermal Storage Materials Laboratory Thermal Storage Process and Components Laboratory Thin-Film Deposition

Fuzzy Energy Management for a Catenary-Battery-Ultracapacitor based Hybrid Tramway

NASA Astrophysics Data System (ADS)

Jibin, Yang; Jiye, Zhang; Pengyun, Song

2017-05-01

In this paper, an energy management strategy (EMS) based on fuzzy logic control for a catenary-battery-ultracapacitor powered hybrid modern tramway was presented. The fuzzy logic controller for the catenary zone and catenary-less zone was respectively designed by analyzing the structure and working mode of the hybrid system, then an energy management strategy based on double fuzzy logic control was proposed to enhance the fuel economy. The hybrid modern tramway simulation model was developed based on MATLAB/Simulink environment. The simulation results show that the proposed EMS can satisfy the demand of dynamic performance of the tramway and achieve the power distribution reasonably between the each power source.

World Reference Base | FAO SOILS PORTAL | Food and Agriculture

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> Soil classification > World Reference Base FAO SOILS PORTAL Survey Assessment Biodiversity Management Degradation/Restoration Policies/Governance Publications Soil properties Soil classification World Reference Base FAO legend USDA soil taxonomy Universal soil classification National Systems Numerical

Evaluated and Compiled Nuclear Structure Data

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-, Ca, zr-mo, -Na, ...) Nuclide A range: (56, 120-130, 208-, ...) Reaction: ( (n,p), (12c,a), n,g ...) Target: (58Ni, pb-208, ...) Incident: (n, a, 16O, ...) Outgoing: (n, a, 16O, ...) Residual: (58Ni, pb-208 Inelastic Mossbauer Pickup Polarized Stripping Thermal n,g Two-nucleon transfer Search Reset Use this page

Todd Vinzant | NREL

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, microbiology, microscopy, and laboratory management and design. Areas of Expertise Structural and chemical equipment design and construction Education M.S., Microbiology, University of Denver, 1990 B.S., Biology Technologies," Bioresource Technology (2011) "Comparative Material Balances Around Pretreatment

Preserve America News

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Communities Designated; Applications Available Preserve America Stewards Honored Preserve America Grants historic structures and assets. 736 Communities Designated; Applications Available 736 Communities Designated; Applications Available Just before leaving the White House, former First Lady Mrs. Laura Bush

EMC HWRF Weekly Meeting Homepage

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structure using idealized HWRF simulations with GFS and MYJ PBL schemes by Jun Zhang (HRD/AOML) NOAA- MoES Zhan Zhang(EMC) (NOTE: Links open presentations in a new window) Please e-mail comments, questions, or

NREL-Led Research Effort Creates New Alloys, Phase Diagram | News | NREL

Science.gov Websites

example of what happens when you bring different institutions with different capabilities together," oxide (ZnO), even though their atomic structures are very different. The new alloy will absorb a deposition and magnetron sputtering. Neither method required such high temperatures. "We show that

Amy Robertson | NREL

Science.gov Websites

validation, and data analysis. At NREL, Amy specializes in the modeling of offshore wind system dynamics. She Amy.Robertson@nrel.gov | 303-384-7157 Amy's expertise is in structural dynamics modeling, verification and of offshore wind modeling tools. Prior to joining NREL, Amy worked as an independent consultant for

Leadership Team | Water Power | NREL

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leading wind energy and water power research efforts in structural analysis and simulation, computational Leadership Team Leadership Team Learn more about the expertise and technical skills of the water power research team and staff at NREL. Photo of Daniel Laird Daniel Laird Center Director I-Technical Dr

Advanced Thermoplastic Resins for Manufacturing Wind Turbine Blades |

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Turbine Blades Advanced Thermoplastic Resins for Manufacturing Wind Turbine Blades At its Composites Arkema's Elium liquid thermoplastic resin. Photo of men working on turbine blades in a dome-shaped building composite structures of wind turbine blades. Capabilities Learn more about NREL's IACMI projects and its

Wind and Water Power Fact Sheets | Wind | NREL

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Advanced Control Turbine Systems to Increase Performance, Decrease Structural Loading of Wind Turbines and and Water Power Fact Sheets Wind and Water Power Fact Sheets The capabilities for research at the National Wind Technology Center (NWTC) are numerous. Below you will find fact sheets about the many

Quantifying Golgi structure using EM: combining volume-SEM and stereology for higher throughput.

PubMed

Ferguson, Sophie; Steyer, Anna M; Mayhew, Terry M; Schwab, Yannick; Lucocq, John Milton

2017-06-01

Investigating organelles such as the Golgi complex depends increasingly on high-throughput quantitative morphological analyses from multiple experimental or genetic conditions. Light microscopy (LM) has been an effective tool for screening but fails to reveal fine details of Golgi structures such as vesicles, tubules and cisternae. Electron microscopy (EM) has sufficient resolution but traditional transmission EM (TEM) methods are slow and inefficient. Newer volume scanning EM (volume-SEM) methods now have the potential to speed up 3D analysis by automated sectioning and imaging. However, they produce large arrays of sections and/or images, which require labour-intensive 3D reconstruction for quantitation on limited cell numbers. Here, we show that the information storage, digital waste and workload involved in using volume-SEM can be reduced substantially using sampling-based stereology. Using the Golgi as an example, we describe how Golgi populations can be sensed quantitatively using single random slices and how accurate quantitative structural data on Golgi organelles of individual cells can be obtained using only 5-10 sections/images taken from a volume-SEM series (thereby sensing population parameters and cell-cell variability). The approach will be useful in techniques such as correlative LM and EM (CLEM) where small samples of cells are treated and where there may be variable responses. For Golgi study, we outline a series of stereological estimators that are suited to these analyses and suggest workflows, which have the potential to enhance the speed and relevance of data acquisition in volume-SEM.

Local Influence Analysis of Nonlinear Structural Equation Models

ERIC Educational Resources Information Center

Lee, Sik-Yum; Tang, Nian-Sheng

2004-01-01

By regarding the latent random vectors as hypothetical missing data and based on the conditional expectation of the complete-data log-likelihood function in the EM algorithm, we investigate assessment of local influence of various perturbation schemes in a nonlinear structural equation model. The basic building blocks of local influence analysis…

Clayton Barrows | NREL

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engineering, Penn State, 2013 B.S. in electrical engineering, University of Wyoming, 2005 Prior Work of Electrical and Electronics Engineers (IEEE) Featured Publications Barrows, Clayton, Trieu Mai and Electrical Structure of the North American Electric Power Infrastructure." IEEE Systems

Defense.gov Special Report: Travels with Gates - December 2010

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Says Gates Salutes Sailors, Marines at Afghanistan Base Secretary Presents Valor Awards to Bastogne at the U.S. Embassy, Kabul Remarks at Forward Operating Base Howz-e-Madad, Afghanistan Remarks at Base Joyce, Afghanistan Remarks at Forward Operating Base Connolly, Afghanistan Media Availabilty at

Christopher Chang | NREL

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transition metal systems, macromolecular dynamics, comparative chemical bonding analysis, electron transfer . Research Interests Dynamics and control on discrete structures, including excited-state transition metal

Publications - GMC 430 | Alaska Division of Geological & Geophysical

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: Formation hardness of Hemlock Formation cores after immersion in water and oil based fracturing fluids; and mechanics: Formation hardness of Hemlock Formation cores after immersion in water and oil based fracturing Surveys Skip to content State of Alaska myAlaska My Government Resident Business in Alaska

Hai Long | NREL

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research interests are broadly in computational modeling for renewable energy generation and energy ions transport in fuel cell and bioenergetics enzymes, and functional membrane structure modeling and University Featured Publications Hydroxide Degradation Pathways for Imidazolium Cations: A DFT Study, J. Phys

Jennifer van Rij | NREL

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Jennifer.Vanrij@nrel.gov | 303-384-7180 Jennifer's expertise is in developing computational modeling methods for collaboratively developing numerical modeling methods to simulate the hydrodynamic, structural dynamic, power -elastic interactions. Her other diverse work experiences include developing numerical modeling methods for

Defense.gov Special Report: Travels with Winnefeld: USO Tour

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Kaneohe Bay - Hawaii Osan Air Base - South Korea CIA Factbook - Diego Garcia Bagram Air Base - Afghanistan Naval Support Activity - Bahrain Naval Support Activity Naples - Italy Ramstein Air Base - Germany Photo Attacked in Seoul Stars Bring Piece of Home to Bagram Airfield During USO Spring Troop Visit Forward Base

N/NC team claims three-peat softball championship title > U.S. Northern

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base championship trophy to Lt. Gen. Michael Dubie, deputy commander United States Northern Command DOWNLOAD HI-RES / PHOTO DETAILS The NORAD-USNORTHCOM silver softball team presented their base championship FORCE BASE, Colo., Feb. 11, 2015 - The NORAD-USNORTHCOM silver softball team presented their base

Newcomers

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commands are located on Peterson Air Force Base. The Base Guide describes some of the services available on our base to include information on the Joint Personal Property Shipping Office (the office in charge Base and in the local area, log into the 21st Force Support Squadron's web site. The 21st Force Support

Siegfried S. Hecker, Plutonium, and Nonproliferation

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controversy involving the stability of certain structures (or phases) in plutonium alloys near equilibrium Cold War is Over. What Now?, DOE Technical Report, April, 1995 6th US-Russian Pu Science Workshop * Aging of Plutonium and Its Alloys * A Tale of Two Diagrams * Plutonium and Its Alloys-From Atoms to

Clifford G. Shull, Neutron Diffraction, Hydrogen Atoms, and Neutron

Science.gov Websites

Analysis of NaH and NaD, DOE Technical Report, April 1947 The Diffraction of Neutrons by Crystalline Powders; DOE Technical Report; 1948 Neutron Diffraction Studies, DOE Technical Report, 1948 Laue Structure of Thorium and Zirconium Dihydrides by X-ray and Neutron Diffraction, DOE Technical Report, April

Gravity currents in rotating channels. Part 1. Steady-state theory

NASA Astrophysics Data System (ADS)

Hacker, J. N.; Linden, P. F.

2002-04-01

A theory is developed for the speed and structure of steady-state non-dissipative gravity currents in rotating channels. The theory is an extension of that of Benjamin (1968) for non-rotating gravity currents, and in a similar way makes use of the steady-state and perfect-fluid (incompressible, inviscid and immiscible) approximations, and supposes the existence of a hydrostatic ‘control point’ in the current some distance away from the nose. The model allows for fully non-hydrostatic and ageostrophic motion in a control volume V ahead of the control point, with the solution being determined by the requirements, consistent with the perfect-fluid approximation, of energy and momentum conservation in V, as expressed by Bernoulli's theorem and a generalized flow-force balance. The governing parameter in the problem, which expresses the strength of the background rotation, is the ratio W = B/R, where B is the channel width and R = (g[prime prime or minute]H)1/2/f is the internal Rossby radius of deformation based on the total depth of the ambient fluid H. Analytic solutions are determined for the particular case of zero front-relative flow within the gravity current. For each value of W there is a unique non-dissipative two-layer solution, and a non-dissipative one-layer solution which is specified by the value of the wall-depth h0. In the two-layer case, the non-dimensional propagation speed c = cf(g[prime prime or minute]H)[minus sign]1/2 increases smoothly from the non-rotating value of 0.5 as W increases, asymptoting to unity for W [rightward arrow] [infty infinity]. The gravity current separates from the left-hand wall of the channel at W = 0.67 and thereafter has decreasing width. The depth of the current at the right-hand wall, h0, increases, reaching the full depth at W = 1.90, after which point the interface outcrops on both the upper and lower boundaries, with the distance over which the interface slopes being 0.881R. In the one-layer case, the wall-depth based propagation speed Froude number c0 = cf(g[prime prime or minute]h0)[minus sign]1/2 = 21/2, as in the non-rotating one-layer case. The current separates from the left-hand wall of the channel at W0 [identical with] B/R0 = 2[minus sign]1/2, and thereafter has width 2[minus sign]1/2R0, where R0 = (g[prime prime or minute]h0)1/2/f is the wall-depth based deformation radius.

Mathematics and Computer Science | Argonne National Laboratory

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Genomics and Systems Biology LCRCLaboratory Computing Resource Center MCSGMidwest Center for Structural Genomics NAISENorthwestern-Argonne Institute of Science & Engineering SBCStructural Biology Center

The Particle Adventure | What is fundamental? | Fundamental

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Quiz - What particles are made of The four interactions How does matter interact? The unseen effect structure Rutherford's result Rutherford's analysis How physicists experiment Deflected probe Detecting the Energy-mass conversion Accelerators How to obtain particles to accelerate Accelerating particles

Nuclear Data Sheets page at the NNDC

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for ENDF. 2014 - ND2013 Conference Proceedings. Topics include the opening and plenary talks, ENDF-6 Conference Proceedings. Topics include neutron induced reactions, gamma and charged particle induced . Topics include mass evaluations, nuclear structure, antineutrino studies, medical physics, education, and

Bioenergy Research | Bioenergy | NREL

Science.gov Websites

range of research from exploring biomass at the molecular level through biorefinery process optimization Bioenergetics We work at the molecular and cellular level to understand and optimize microbial production of biofuels and bioproducts. fanciful illustration of fuel nozzle with molecular structures drawn in

Ryan M. Ness | NREL

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Interests Ryan M. Ness is a research technician in the Biomass Analysis group within the National Renewable , wet chemical analysis, and instrumental analysis of lignocellulosic biomass feedstocks. Bench-scale Publications "The Effect of Biomass Densification on Structural Sugar Release and Yield in Biofuel

Defense.gov - Special Report - Travels With Gates

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Force Base, Ala. Story» Warfighter Care at Center of 2010 Budget Considerations MAXWELL AIR FORCE BASE , Ala., April 15, 2009 – Defense Secretary Robert M. Gates met at Maxwell Air Force Base, Ala., with the U.S. Air Force Air War College on Maxwell Air Force Base, Ala., listen to Defense Secretary Robert

Defense.gov Special Report: Travels With Hagel

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Force base on the Florida panhandle, talking to pilots from the 33rd Fighter Wing, meeting with and in an F-35 fighter. Troop Event At Eglin Air Force Base More Video Hagel Troop Event Kings Bay Travel Locations Map of Hagel's Trip Naval Submarine Base Kings Bay, Georgia. Eglin Air Force Base, Florida. Fort

Chemical Dynamics of nano-Aluminum and Iodine Based Oxidizers

NASA Astrophysics Data System (ADS)

Little, Brian; Ridge, Claron; Overdeep, Kyle; Slizewski, Dylan; Lindsay, Michael

2017-06-01

As observed in previous studies of nanoenergetic powder composites, micro/nano-structural features such as particle morphology and/or reactant spatial distance are expected to strongly influence properties that govern the combustion behavior of energetic materials (EM). In this study, highly reactive composites containing crystalline iodine (V) oxide or iodate salts with nano-sized aluminum (nAl) were blended by two different processing techniques and then collected as a powder for characterization. Physiochemical techniques such as thermal gravimetric analysis, calorimetry, X-ray diffraction, electron microscopy, high speed photography, pressure profile analysis, temperature programmed reactions, and spectroscopy were employed to characterize these EM with emphasis on correlating the chemical reactivity with inherent structural features and variations in stoichiometry. This work is a continuation of efforts to probe the chemical dynamics of nAl-iodine based composites.

The Electron Microscopy Outreach Program: A Web-based resource for research and education.

PubMed

Sosinsky, G E; Baker, T S; Hand, G; Ellisman, M H

1999-01-01

We have developed a centralized World Wide Web (WWW)-based environment that serves as a resource of software tools and expertise for biological electron microscopy. A major focus is molecular electron microscopy, but the site also includes information and links on structural biology at all levels of resolution. This site serves to help integrate or link structural biology techniques in accordance with user needs. The WWW site, called the Electron Microscopy (EM) Outreach Program (URL: http://emoutreach.sdsc.edu), provides scientists with computational and educational tools for their research and edification. In particular, we have set up a centralized resource containing course notes, references, and links to image analysis and three-dimensional reconstruction software for investigators wanting to learn about EM techniques either within or outside of their fields of expertise. Copyright 1999 Academic Press.

OAS :: Our Structure

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General Assembly Governance H Human Development Human Rights I Indigenous Peoples Integral Development Scholarships School of Governance Science and Technology Social Development Summits of the Americas Sustainable

OAS :: Our History

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institutions in different spheres. The Conferences of American States met at varying intervals until, in 1970 English Español Português Français Search OAS Logo OAS Logo Home button About the OAS Who We Are What We Do Our Structure Our Locations Contact Us Access to Information Offices in the Member

Alternative Fuels Data Center: Compressed Natural Gas Fueling Stations

Science.gov Websites

infrastructure: time-fill and fast-fill. The main structural differences between the two systems are the amount fuel dispensed and the time it takes for CNG to be delivered. Most CNG stations include one of these into account. Learn more about filling CNG tanks. Time-Fill CNG Station Enlarge illustration Time-fill

Smoot Cosmology Group

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History of COBE project Structure in the COBE differential microwave radiometer first-year maps. Smoot, et (Wilkinson Microwave Anisotropy Probe) CMB satellite 5 year data papers Introduction NASA's COBE (Cosmic compare the spectrum of the cosmic microwave background radiation with that from a precise blackbody. Data

Donald Baker | NREL

Science.gov Websites

-7162 Don assists with the installation and maintenance of the NWTC's field test turbines as well as with test article installations and testing in the Structural Testing Laboratory and both dynamometer facilities. He participates in the operation and maintenance of the field test sites and meteorological

NOAA Office of Exploration and Research > Public Affairs > Website & Social

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Partners Materials NOAA Initiatives Partnerships Evaluation Public Affairs Overview Website & Social Media News Room OER Symposium Overview Website & Social Media News Room OER Symposium Public Affairs Website & Social Media Home About OER Overview Organization Guiding Documents Organizational Structure

Berkeley Lab - Materials Sciences Division

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Postdoc Forum Research Highlights Awards Publications Database Events Calendar Newsletter Archive People ; Finance Templates Travel One-Stop Investigators Division Staff Facilities and Centers Staff Jobs People Division, please use the links here. An outline of the Division structure is available at the Organization

FitEM2EM—Tools for Low Resolution Study of Macromolecular Assembly and Dynamics

PubMed Central

Frankenstein, Ziv; Sperling, Joseph; Sperling, Ruth; Eisenstein, Miriam

2008-01-01

Studies of the structure and dynamics of macromolecular assemblies often involve comparison of low resolution models obtained using different techniques such as electron microscopy or atomic force microscopy. We present new computational tools for comparing (matching) and docking of low resolution structures, based on shape complementarity. The matched or docked objects are represented by three dimensional grids where the value of each grid point depends on its position with regard to the interior, surface or exterior of the object. The grids are correlated using fast Fourier transformations producing either matches of related objects or docking models depending on the details of the grid representations. The procedures incorporate thickening and smoothing of the surfaces of the objects which effectively compensates for differences in the resolution of the matched/docked objects, circumventing the need for resolution modification. The presented matching tool FitEM2EMin successfully fitted electron microscopy structures obtained at different resolutions, different conformers of the same structure and partial structures, ranking correct matches at the top in every case. The differences between the grid representations of the matched objects can be used to study conformation differences or to characterize the size and shape of substructures. The presented low-to-low docking tool FitEM2EMout ranked the expected models at the top. PMID:18974836

Dave Simms | NREL

Science.gov Websites

coming to NREL, Dave was an Air Force officer and led a variety of defense science and engineering efforts in fluid dynamics, combustion, structures, materials, nanotechnology, multidisciplinary design

Publications - RI 2000-1A | Alaska Division of Geological & Geophysical

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; Folding; Formations; Fossils; Generalized; Geologic; Geologic Map; Geology; Geomorphology; Glacial ; Silt; Structure; Surficial; Surficial Geology; Tectonics; Tertiary; Thaw Lakes; Trace Fossils

Latha Sethuraman | NREL

Science.gov Websites

aeroelastic simulation of drivetrain systems. At NREL, she supports the drivetrain modeling effort under the , electro-mechanical system design and optimization, structural analysis, and multi-body simulation. In

Low cost, high performance processing of single particle cryo-electron microscopy data in the cloud.

PubMed

Cianfrocco, Michael A; Leschziner, Andres E

2015-05-08

The advent of a new generation of electron microscopes and direct electron detectors has realized the potential of single particle cryo-electron microscopy (cryo-EM) as a technique to generate high-resolution structures. Calculating these structures requires high performance computing clusters, a resource that may be limiting to many likely cryo-EM users. To address this limitation and facilitate the spread of cryo-EM, we developed a publicly available 'off-the-shelf' computing environment on Amazon's elastic cloud computing infrastructure. This environment provides users with single particle cryo-EM software packages and the ability to create computing clusters with 16-480+ CPUs. We tested our computing environment using a publicly available 80S yeast ribosome dataset and estimate that laboratories could determine high-resolution cryo-EM structures for $50 to $1500 per structure within a timeframe comparable to local clusters. Our analysis shows that Amazon's cloud computing environment may offer a viable computing environment for cryo-EM.

Units

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Maxwell Air Force Base Maxwell Air Force Base Join the Air Force Home News AF News Commentaries Services SAPR FOIA Retiree Activities Office Centennial Search Maxwell Air Force Base: Home > Units Site

Alternative Fuels Data Center: Silicon Valley-based Electric Vehicle Parade

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Breaks Guinness World Record Silicon Valley-based Electric Vehicle Parade Breaks Guinness World Parade Breaks Guinness World Record on Facebook Tweet about Alternative Fuels Data Center: Silicon Valley -based Electric Vehicle Parade Breaks Guinness World Record on Twitter Bookmark Alternative Fuels Data

Case-Deletion Diagnostics for Nonlinear Structural Equation Models

ERIC Educational Resources Information Center

Lee, Sik-Yum; Lu, Bin

2003-01-01

In this article, a case-deletion procedure is proposed to detect influential observations in a nonlinear structural equation model. The key idea is to develop the diagnostic measures based on the conditional expectation of the complete-data log-likelihood function in the EM algorithm. An one-step pseudo approximation is proposed to reduce the…

Electronic Structure Theory | Materials Science | NREL

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design and discover materials for energy applications. This includes detailed studies of the physical computing. Key Research Areas Materials by Design NREL leads the U.S. Department of Energy's Center for Next Generation of Materials by Design, which incorporates metastability and synthesizability. Learn more about

Publications - RDF 2011-1 | Alaska Division of Geological & Geophysical

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Solomon Quadrangle, Seward Peninsula, Alaska Authors: Werdon, M.B. Publication Date: Mar 2011 Publisher or please see our publication sales page for more information. Quadrangle(s): Solomon Bibliographic Reference Werdon, M.B., 2011, Outcrop structural data collected in 2006 in the Solomon Quadrangle, Seward

Alaska Division of Geological & Geophysical Surveys

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Publications Search Statewide Maps New Releases Sales Interactive Maps Databases Sections Geologic hazards to buildings, roads, bridges, and other installations and structures (AS 41.08.020). Headlines New release! Active faults and seismic hazards in Alaska - MP 160 New release! The Alaska Volcano Observatory

Command Sgt. Maj. John Wayne Troxell > Joint Chiefs of Staff > Article View

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DOCNET Leadership CJCS | Gen. Dunford on Flickr VCJCS | Gen. Selva on Flickr SEAC | CSM Troxell on J8 | Force Structure, Resources & Assessment Contact Home : Leadership : Article View Command Sgt includes Ranger, Airborne, Jumpmaster, Pathfinder, the Primary Leadership Development Course, the Basic

Polar Vortices Observed in Ferroelectric | Berkeley Lab

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vortices" that appear to be the electrical cousins of magnetic skyrmions holds intriguing structures are confined to magnetic systems and aren't possible in ferroelectric materials, but through the . Ferroic materials display unique electrical or magnetic properties - or both in the case of multiferroics

OAS :: Secretariat for Strengthening Democracy (SSD)

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Structure Our Locations Contact Us Access to Information Offices in the Member States Our History Logo Authorities Services Legal Protocol Topics A Access to Information Access to Rights Actions against Corruption Management Public Security R Racism and Intolerance Refugees S Scholarships School of Governance Science and

Interns and Volunteers, Department of Vertebrate Zoology, NMNH

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Skip to main content. Smithsonian National Museum of Natural History Donate Website Search Box Opportunities Internships The National Museum of Natural History offers internships in the Department of History is a prearranged, structured learning experience scheduled within a specific time frame. The

ACHP | News

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structures that will be used to support fixed wireless antennas within the existing railroad right of way alongside existing tracks. The antennas are used to support the wireless flow of information needed for the : Steve DelSordo, Federal Preservation Officer of the FCC Wireless Telecommunications Bureau at (202) 418

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SubspaceEM: A Fast Maximum-a-posteriori Algorithm for Cryo-EM Single Particle Reconstruction

PubMed Central

Dvornek, Nicha C.; Sigworth, Fred J.; Tagare, Hemant D.

2015-01-01

Single particle reconstruction methods based on the maximum-likelihood principle and the expectation-maximization (E–M) algorithm are popular because of their ability to produce high resolution structures. However, these algorithms are computationally very expensive, requiring a network of computational servers. To overcome this computational bottleneck, we propose a new mathematical framework for accelerating maximum-likelihood reconstructions. The speedup is by orders of magnitude and the proposed algorithm produces similar quality reconstructions compared to the standard maximum-likelihood formulation. Our approach uses subspace approximations of the cryo-electron microscopy (cryo-EM) data and projection images, greatly reducing the number of image transformations and comparisons that are computed. Experiments using simulated and actual cryo-EM data show that speedup in overall execution time compared to traditional maximum-likelihood reconstruction reaches factors of over 300. PMID:25839831

Northridge 20 Symposium

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billion in direct damage. The event spurred important changes to the current practice of earthquake engineering and risk mitigation worldwide, including changes to building codes for steel structures and multi

Structural Molecular Biology 2017 | SSRL

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sustain and enhance the general user program through excellent support, training and dissemination. Close × Acknowledgement The SSRL SMB Resource supports the development of advanced methodologies and

Adele Tamboli | NREL

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Carlo simulations of disorder in ZnSnN2 and the effects on the electronic structure," Physical Review Materials, 2017 "Effects of Hydrogen on Acceptor Activation in Ternary Nitride Semiconductors

Cryo-EM near-atomic structure of a dsRNA fungal virus shows ancient structural motifs preserved in the dsRNA viral lineage

PubMed Central

Luque, Daniel; Gómez-Blanco, Josué; Garriga, Damiá; Brilot, Axel F.; González, José M.; Havens, Wendy M.; Carrascosa, José L.; Trus, Benes L.; Verdaguer, Nuria; Ghabrial, Said A.; Castón, José R.

2014-01-01

Viruses evolve so rapidly that sequence-based comparison is not suitable for detecting relatedness among distant viruses. Structure-based comparisons suggest that evolution led to a small number of viral classes or lineages that can be grouped by capsid protein (CP) folds. Here, we report that the CP structure of the fungal dsRNA Penicillium chrysogenum virus (PcV) shows the progenitor fold of the dsRNA virus lineage and suggests a relationship between lineages. Cryo-EM structure at near-atomic resolution showed that the 982-aa PcV CP is formed by a repeated α-helical core, indicative of gene duplication despite lack of sequence similarity between the two halves. Superimposition of secondary structure elements identified a single “hotspot” at which variation is introduced by insertion of peptide segments. Structural comparison of PcV and other distantly related dsRNA viruses detected preferential insertion sites at which the complexity of the conserved α-helical core, made up of ancestral structural motifs that have acted as a skeleton, might have increased, leading to evolution of the highly varied current structures. Analyses of structural motifs only apparent after systematic structural comparisons indicated that the hallmark fold preserved in the dsRNA virus lineage shares a long (spinal) α-helix tangential to the capsid surface with the head-tailed phage and herpesvirus viral lineage. PMID:24821769

Climate Prediction Center - United States Drought Information

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• Crop Moisture Indices • Soil Moisture Percentiles (based on NLDAS) • Standardized Runoff Index (based /Minimum • Mean Surface Hydrology (based on NLDAS) • Total Soil Moisture • Total SM Change • MOSAIC Soil Moisture Profile • NOAH Soil Moisture Profile • NOAH Soil T Profile • Evaporation • E-P Â

Astrometry Information Center - Naval Oceanography Portal

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are here: Home › USNO › Astrometry › Astrometry Information Center USNO Logo USNO Navigation Optical/IR Products VLBI-based Products Astrometry Information Center Catalog Information Double Star Information VLBI-based Product Information Info Astrometry Information Center Within the astrometry

Office of Economic Adjustment | U.S. Department of Defense

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Reuse Compatible Use Defense Contractor Transitions Federal Assistance Coordination Mission Change contractor or manufacturer is making cuts or closing. Explore BRAC Icon Base Realignment and Closure A contact information. What We Do Base Closure Base Realignment Base Reuse Compatible Use Defense Contractor

The feasibility of imaging subglacial hydrology beneath ice streams with ground-based electromagnetics

NASA Astrophysics Data System (ADS)

Siegfried, M. R.; Key, K.

2017-12-01

Subglacial hydrologic systems in Antarctica and Greenland play a fundamental role in ice-sheet dynamics, yet critical aspects of these systems remain poorly understood due to a lack of observations. Ground-based electromagnetic (EM) geophysical methods are established for mapping groundwater in many environments, but have never been applied to imaging lakes beneath ice sheets. Here we study the feasibility of passive and active source EM imaging for quantifying the nature of subglacial water systems beneath ice streams, with an emphasis on the interfaces between ice and basal meltwater, as well as deeper groundwater in the underlying sediments. Specifically, we look at the passive magnetotelluric method and active-source EM methods that use a large loop transmitter and receivers that measure either frequency-domain or transient soundings. We describe a suite of model studies that exam the data sensitivity as a function of ice thickness, water conductivity and hydrologic system geometry for models representative of a subglacial lake and a grounding zone estuary. We show that EM data are directly sensitive to groundwater and can image its lateral and depth extent. By combining the conductivity obtained from EM data with ice thickness and geological structure from conventional geophysical techniques such as ground-penetrating radar and active seismic techniques, EM data have the potential to provide new insights on the interaction between ice, rock, and water at critical ice-sheet boundaries.

Tsunami Research Program | PEER Center

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including coastal bridges, and important public facilities (fire and police stations, hospitals, and schools ). Failure of critical coastal structures and lifelines likely lead to loss of life, delays in emergency

Libraries for Software Use on Peregrine | High-Performance Computing | NREL

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-specific libraries. Libraries List Name Description BLAS Basic Linear Algebra Subroutines, libraries only managing hierarchically structured data. LAPACK Standard Netlib offering for computational linear algebra

Thermal Measurements of Packed Copper Wire Enables Better Electric Motor

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transmittance characterization methods both parallel and perpendicular to the axis. A measurement of apparent from all three test methods indicated that the k_app of the packed copper wire was significantly higher methods for examining the thermal impact of new materials for winding structures relevant to motor

Green Banks | State, Local, and Tribal Governments | NREL

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, and a commercial property assessed clean energy (PACE) product for a variety of different energy , Green Banks can help to help secure private capital by a number of different means including lowering Formation State and local governments have established Green Banks under a variety of different structures

Nanoscale Confinement Leads to New All-inorganic Perovskite with

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research into perovskites has centered on a hybrid organic-inorganic structure. Since research into climbed steadily and now shows greater than 22 percent power conversion efficiency. However, the organic unstable organic component and open the door to high-efficiency quantum dot optoelectronics that can be

Systems Engineering 2015 Workshop | Wind | NREL

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Dhert, University of Michigan High-Fidelity Aerodynamic Shape Optimization for Wind Turbines Kristian ; Different design approaches are applied to determine the shape as well as the structural composition of the turbine that also found a significant trade-off between the lighter blades and a heavier tower moving from

Structural Research Facilities | Wind | NREL

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enable the characterization and validation of wind turbine blades and components. A photo of a wind operating loads experienced by blades during field operation and accelerated fatigue lifetime loading can be are capable of validating blades and components smaller than 1 meter (m) to more than 50 m in length

Martinus Veltman, the Electroweak Theory, and Elementary Particle Physics

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Particle Physics Resources with Additional Information Martinus Veltman Courtesy University of Michigan Martinus J.G. Veltman, the John D. MacArthur Professor Emeritus of Physics at the University of Michigan , was awarded the 1999 Nobel Prize in physics "for elucidating the quantum structure of electroweak

H. David Politzer, Asymptotic Freedom, and Strong Interaction

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Possible Non-Regge Behavior of Electroproduction Structure Functions; Physical Review D, Vol. 10, Issue 5 ; 1974 Heavy Quarks and Long-lived Hadrons; Physical Review D, Vol. 12, Issue 5; 1975 Experimental take you to non-federal websites. Their policies may differ from this site. Website Policies/Important

Dan Says - Continuum Magazine | NREL

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efficiency of residential and commercial buildings. At first glance, energy efficiency may not seem as and commercial structures account for more than 70% of all electricity used in the United States. That end of the decade. That is why improving the energy efficiency of our homes and commercial buildings

Automated structure refinement of macromolecular assemblies from cryo-EM maps using Rosetta.

PubMed

Wang, Ray Yu-Ruei; Song, Yifan; Barad, Benjamin A; Cheng, Yifan; Fraser, James S; DiMaio, Frank

2016-09-26

Cryo-EM has revealed the structures of many challenging yet exciting macromolecular assemblies at near-atomic resolution (3-4.5Å), providing biological phenomena with molecular descriptions. However, at these resolutions, accurately positioning individual atoms remains challenging and error-prone. Manually refining thousands of amino acids - typical in a macromolecular assembly - is tedious and time-consuming. We present an automated method that can improve the atomic details in models that are manually built in near-atomic-resolution cryo-EM maps. Applying the method to three systems recently solved by cryo-EM, we are able to improve model geometry while maintaining the fit-to-density. Backbone placement errors are automatically detected and corrected, and the refinement shows a large radius of convergence. The results demonstrate that the method is amenable to structures with symmetry, of very large size, and containing RNA as well as covalently bound ligands. The method should streamline the cryo-EM structure determination process, providing accurate and unbiased atomic structure interpretation of such maps.

@NWTC Newsletter: Summer 2015 | Wind | NREL

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Structural Testing of the Blade Reliability Collaborative Effect of Defect Wind Turbine Blades Gearbox Reliability Collaborative Phase 3 Gearbox 2 Test Report Modeling Dynamic Stall on Wind Turbine Blades Under

Alternative Fuels Data Center: Houston Energizes Deployment of Plug-In

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and other pollutant emissions: buildings and structures, mobile sources, and waste (also read more recent reports). Vehicle electrification became a key focus of mobile source emissions-reduction

Defense.gov - Special Report: Travels with Lynn

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social media. Story Simulation Center Provides Taste of Combat MARINE CORPS BASE CAMP PENDELTON, Calif Force's battle simulation center at Marine Corps Base Camp Pendleton, Calif. Story 'Adaptable' U.S. Troops Visits Vandenberg Air Force Base and Los Angeles Lynn Visits Navy and Marine Bases About This Site DoD

Energy Landscapes: From Protein Folding to Molecular Assembly

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been used, for example, in DNA origami, in which artificial structures and machines are built in a mechanical processes and eventually to reproduce these in artificial machines. This conference will provide

NREL Engineer Robert McCormick Named SAE Fellow | News | NREL

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standards. His research has included studies on biodiesel chemistry effects that led to the development of ASTM fuel quality standards and research into oxygenate chemical structure effects on gasoline

High Performance Structures and Materials

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advanced simulation and optimization methods that can be used during the early design stages of innovative Development of Simulation Model Validation Framework for RBDO Sponsored by U.S. Army TARDEC Visit Us Contact

SNAST 2018

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room) or while being on the mobile (agents in action). While desktop based applications can be used to monitor but also process and analyse surveillance data coming from a variety of sources, mobile-based techniques Digital forensics analysis Visualization techniques for surveillance Mobile-based surveillance

Low cost, high performance processing of single particle cryo-electron microscopy data in the cloud

PubMed Central

Cianfrocco, Michael A; Leschziner, Andres E

2015-01-01

The advent of a new generation of electron microscopes and direct electron detectors has realized the potential of single particle cryo-electron microscopy (cryo-EM) as a technique to generate high-resolution structures. Calculating these structures requires high performance computing clusters, a resource that may be limiting to many likely cryo-EM users. To address this limitation and facilitate the spread of cryo-EM, we developed a publicly available ‘off-the-shelf’ computing environment on Amazon's elastic cloud computing infrastructure. This environment provides users with single particle cryo-EM software packages and the ability to create computing clusters with 16–480+ CPUs. We tested our computing environment using a publicly available 80S yeast ribosome dataset and estimate that laboratories could determine high-resolution cryo-EM structures for $50 to $1500 per structure within a timeframe comparable to local clusters. Our analysis shows that Amazon's cloud computing environment may offer a viable computing environment for cryo-EM. DOI: http://dx.doi.org/10.7554/eLife.06664.001 PMID:25955969

Joint Chiefs of Staff > Directorates > J5 | Strategic Plans and Policy

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Quadrilateral Logistics Forum J5 | Strategic Plans and Policy J6 | C4 & Cyber J7 | Joint Force Development J8 | Force Structure, Resources & Assessment Contact J5 Strategic Plans and Policy Home : Directorates : J5 | Strategic Plans and Policy Mission The Joint Staff J5 proposes strategies, plans, and

NCEP BUFR File Structure

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. These tables may be defined within a separate ASCII text file (see Description and Format of BUFR Tables time, the BUFR tables are usually read from an external ASCII text file (although it is also possible reports. Click here to view the ASCII text file (called /nwprod/fix/bufrtab.002 on the NCEP CCS machines

ACHP | Working Together to Build a More Inclusive Preservation Program

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Search skip specific nav links Home arrow Inclusiveness arrow Jay Vogt Interview Interview with Jay D Often times when we think about history, we think of people...who they are and what they accomplished people made and left behind, such as written records, objects, buildings, and structures...houses from

Joint Chiefs of Staff > Directorates > J1 | Manpower and Personnel

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Management J1 | Manpower and Personnel J2 | Joint Staff Intelligence J3 | Operations J4 | Logistics► J8 | Force Structure, Resources & Assessment Contact J1 Manpower and Personnel Home : Directorates : J1 | Manpower and Personnel Mission To provide the Chairman of the Joint Chiefs of Staff

The Universe Adventure - The Beginnings of Cosmology

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The Universe Adventure [ next ] [ home ] Go The Beginnings of Cosmology Since the beginning of of stars? What do the stars tell us about the future? Where did the Universe come from? Cosmology is will introduce you to Cosmology and the study of the structure, history, and fate of the Universe. In

Staff - Marwan A. Wartes | Alaska Division of Geological & Geophysical

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programs, offering expertise in sedimentary geology and tectonics. My background is primarily in outcrop : Archives of coupled structural and sedimentary processes (GSA/AAPG) FIELD TRIP LEADERSHIP 2017, Field trip China: Journal of Sedimentary Research, v. 75, no. 2, p. 268-279. Carroll, A.R., and Wartes, M.A., 2003

Very high-frequency gravitational waves from magnetars and gamma-ray bursts

NASA Astrophysics Data System (ADS)

Wen, Hao; Li, Fang-Yu; Li, Jin; Fang, Zhen-Yun; Beckwith, Andrew

2017-12-01

Extremely powerful astrophysical electromagnetic (EM) systems could be possible sources of high-frequency gravitational waves (HFGWs). Here, based on properties of magnetars and gamma-ray bursts (GRBs), we address “Gamma-HFGWs” (with very high-frequency around 1020 Hz) caused by ultra-strong EM radiation (in the radiation-dominated phase of GRB fireballs) interacting with super-high magnetar surface magnetic fields (˜1011 T). By certain parameters of distance and power, the Gamma-HFGWs would have far field energy density Ω gw around 10-6, and they would cause perturbed signal EM waves of ˜10-20 W/m2 in a proposed HFGW detection system based on the EM response to GWs. Specially, Gamma-HFGWs would possess distinctive envelopes with characteristic shapes depending on the particular structures of surface magnetic fields of magnetars, which could be exclusive features helpful to distinguish them from background noise. Results obtained suggest that magnetars could be involved in possible astrophysical EM sources of GWs in the very high-frequency band, and Gamma-HFGWs could be potential targets for observations in the future. Supported by National Natural Science Foundation of China (11605015, 11375279, 11205254, 11647307) and the Fundamental Research Funds for the Central Universities (106112017CDJXY300003, 106112017CDJXFLX0014)

GEONETCastAmericas

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satellite-based data dissemination systems designed to distribute space-based, air-borne and in situ data ) satellite to broadcast environmental and other observation data to an area covering most of North, Central up the broadcast using inexpensive satellite receiver stations based on Digital Video Broadcast (DVB

Parasitic Parameters Extraction for InP DHBT Based on EM Method and Validation up to H-Band

NASA Astrophysics Data System (ADS)

Li, Oupeng; Zhang, Yong; Wang, Lei; Xu, Ruimin; Cheng, Wei; Wang, Yuan; Lu, Haiyan

2017-05-01

This paper presents a small-signal model for InGaAs/InP double heterojunction bipolar transistor (DHBT). Parasitic parameters of access via and electrode finger are extracted by 3-D electromagnetic (EM) simulation. By analyzing the equivalent circuit of seven special structures and using the EM simulation results, the parasitic parameters are extracted systematically. Compared with multi-port s-parameter EM model, the equivalent circuit model has clear physical intension and avoids the complex internal ports setting. The model is validated on a 0.5 × 7 μm2 InP DHBT up to 325 GHz. The model provides a good fitting result between measured and simulated multi-bias s-parameters in full band. At last, an H-band amplifier is designed and fabricated for further verification. The measured amplifier performance is highly agreed with the model prediction, which indicates the model has good accuracy in submillimeterwave band.

Sequential computation of elementary modes and minimal cut sets in genome-scale metabolic networks using alternate integer linear programming.

PubMed

Song, Hyun-Seob; Goldberg, Noam; Mahajan, Ashutosh; Ramkrishna, Doraiswami

2017-08-01

Elementary (flux) modes (EMs) have served as a valuable tool for investigating structural and functional properties of metabolic networks. Identification of the full set of EMs in genome-scale networks remains challenging due to combinatorial explosion of EMs in complex networks. It is often, however, that only a small subset of relevant EMs needs to be known, for which optimization-based sequential computation is a useful alternative. Most of the currently available methods along this line are based on the iterative use of mixed integer linear programming (MILP), the effectiveness of which significantly deteriorates as the number of iterations builds up. To alleviate the computational burden associated with the MILP implementation, we here present a novel optimization algorithm termed alternate integer linear programming (AILP). Our algorithm was designed to iteratively solve a pair of integer programming (IP) and linear programming (LP) to compute EMs in a sequential manner. In each step, the IP identifies a minimal subset of reactions, the deletion of which disables all previously identified EMs. Thus, a subsequent LP solution subject to this reaction deletion constraint becomes a distinct EM. In cases where no feasible LP solution is available, IP-derived reaction deletion sets represent minimal cut sets (MCSs). Despite the additional computation of MCSs, AILP achieved significant time reduction in computing EMs by orders of magnitude. The proposed AILP algorithm not only offers a computational advantage in the EM analysis of genome-scale networks, but also improves the understanding of the linkage between EMs and MCSs. The software is implemented in Matlab, and is provided as supplementary information . hyunseob.song@pnnl.gov. Supplementary data are available at Bioinformatics online. Published by Oxford University Press 2017. This work is written by US Government employees and are in the public domain in the US.

Filling the Gap: Simulation-based Crisis Resource Management Training for Emergency Medicine Residents.

PubMed

Parsons, Jessica R; Crichlow, Amanda; Ponnuru, Srikala; Shewokis, Patricia A; Goswami, Varsha; Griswold, Sharon

2018-01-01

In today's team-oriented healthcare environment, high-quality patient care requires physicians to possess not only medical knowledge and technical skills but also crisis resource management (CRM) skills. In emergency medicine (EM), the high acuity and dynamic environment makes CRM skills of physicians particularly critical to healthcare team success. The Accreditation Council of Graduate Medicine Education Core Competencies that guide residency program curriculums include CRM skills; however, EM residency programs are not given specific instructions as to how to teach these skills to their trainees. This article describes a simulation-based CRM course designed specifically for novice EM residents. The CRM course includes an introductory didactic presentation followed by a series of simulation scenarios and structured debriefs. The course is designed to use observational learning within simulation education to decrease the time and resources required for implementation. To assess the effectiveness in improving team CRM skills, two independent raters use a validated CRM global rating scale to measure the CRM skills displayed by teams of EM interns in a pretest and posttest during the course. The CRM course improved leadership, problem solving, communication, situational awareness, teamwork, resource utilization and overall CRM skills displayed by teams of EM interns. While the improvement from pretest to posttest did not reach statistical significance for this pilot study, the large effect sizes suggest that statistical significance may be achieved with a larger sample size. This course can feasibly be incorporated into existing EM residency curriculums to provide EM trainees with basic CRM skills required of successful emergency physicians. We believe integrating CRM training early into existing EM education encourages continued deliberate practice, discussion, and improvement of essential CRM skills.

Web-Based Time Synchronization - Naval Oceanography Portal

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section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › Display Clocks USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info Web-Based Time Synchronization Web time displays from the

CryoEM and image sorting for flexible protein/DNA complexes.

PubMed

Villarreal, Seth A; Stewart, Phoebe L

2014-07-01

Intrinsically disordered regions of proteins and conformational flexibility within complexes can be critical for biological function. However, disorder, flexibility, and heterogeneity often hinder structural analyses. CryoEM and single particle image processing techniques offer the possibility of imaging samples with significant flexibility. Division of particle images into more homogenous subsets after data acquisition can help compensate for heterogeneity within the sample. We present the utility of an eigenimage sorting analysis for examining two protein/DNA complexes with significant conformational flexibility and heterogeneity. These complexes are integral to the non-homologous end joining pathway, and are involved in the repair of double strand breaks of DNA. Both complexes include the DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and biotinylated DNA with bound streptavidin, with one complex containing the Ku heterodimer. Initial 3D reconstructions of the two DNA-PKcs complexes resembled a cryoEM structure of uncomplexed DNA-PKcs without additional density clearly attributable to the remaining components. Application of eigenimage sorting allowed division of the DNA-PKcs complex datasets into more homogeneous subsets. This led to visualization of density near the base of the DNA-PKcs that can be attributed to DNA, streptavidin, and Ku. However, comparison of projections of the subset structures with 2D class averages indicated that a significant level of heterogeneity remained within each subset. In summary, image sorting methods allowed visualization of extra density near the base of DNA-PKcs, suggesting that DNA binds in the vicinity of the base of the molecule and potentially to a flexible region of DNA-PKcs. Copyright © 2013 Elsevier Inc. All rights reserved.

165th Airlift Wing > Home

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Questions Search 165th Airlift Wing: Featured Links Quick Contacts Organization Phone Number Base Locator Chronicle is our way of communicating with our unit members, their families and our extended fan-base. This Air Base command sgt major visits Pennsylvania ANG Oklahoma National Guard provides Joint Terminal

Home

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water advisory 170926 CLICK HERE HEALTH ADVISORY 20170923; On-base water tests positive for E. coli /appointment/building.aspx?BuildingId=447 More PHONE LISTING BASE STATUS 1-888-INFO-UTA SUSPICIOUS ACTIVITY 215 EDUCATION/RETENTION 215-323-7414 PERSONNEL / I.D. CARDS 215-323-7419 LODGING/SERVICES 215-323-7426 BASE

Defense.gov Special Report: Afghanistan

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Support Soldiers FORWARD OPERATING BASE SHARANA, Afghanistan, May 24, 2011 - Army Lt. Col. Dave Preston BASE TILLMAN, Afghanistan, May 23, 2011 - Where and how you live as a soldier deployed to Afghanistan 14-hour firefight with insurgents. Story Chaplains Prepare for Redeployment FORWARD OPERATING BASE

Maine | Midmarket Solar Policies in the United States | Solar Research |

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multiplier for qualifying community-based renewable energy projects. Maine has a 40% Renewable Portfolio Standard (RPS), with a 1.5 credit multiplier for qualifying community-based renewable energy projects ). Maine-based nonprofits, community action programs, quasi-municipal corporations, and school

Altered functional connectivity architecture of the brain in medication overuse headache using resting state fMRI.

PubMed

Chen, Zhiye; Chen, Xiaoyan; Liu, Mengqi; Dong, Zhao; Ma, Lin; Yu, Shengyuan

2017-12-01

Functional connectivity density (FCD) could identify the abnormal intrinsic and spontaneous activity over the whole brain, and a seed-based resting-state functional connectivity (RSFC) could further reveal the altered functional network with the identified brain regions. This may be an effective assessment strategy for headache research. This study is to investigate the RSFC architecture changes of the brain in the patients with medication overuse headache (MOH) using FCD and RSFC methods. 3D structure images and resting-state functional MRI data were obtained from 37 MOH patients, 18 episodic migraine (EM) patients and 32 normal controls (NCs). FCD was calculated to detect the brain regions with abnormal functional activity over the whole brain, and the seed-based RSFC was performed to explore the functional network changes in MOH and EM. The decreased FCD located in right parahippocampal gyrus, and the increased FCD located in left inferior parietal gyrus and right supramarginal gyrus in MOH compared with NC, and in right caudate and left insula in MOH compared with EM. RSFC revealed that decreased functional connectivity of the brain regions with decreased FCD anchored in the right dorsal-lateral prefrontal cortex, right frontopolar cortex in MOH, and in left temporopolar cortex and bilateral visual cortices in EM compared with NC, and in frontal-temporal-parietal pattern in MOH compared with EM. These results provided evidence that MOH and EM suffered from altered intrinsic functional connectivity architecture, and the current study presented a new perspective for understanding the neuromechanism of MOH and EM pathogenesis.

Venkatraman Ramakrishnan, Thomas A. Steitz, Ada E. Yonath, and Ribosome

Science.gov Websites

'studies of the structure and function of the ribosome", the 2009 Nobel Prize in Chemistry has been ORNL Researcher Wins Nobel Prize Oak Ridge National Laboratory Ex-ORNL Researcher Wins Nobel Prize

Covariance Structure Model Fit Testing under Missing Data: An Application of the Supplemented EM Algorithm

ERIC Educational Resources Information Center

Cai, Li; Lee, Taehun

2009-01-01

We apply the Supplemented EM algorithm (Meng & Rubin, 1991) to address a chronic problem with the "two-stage" fitting of covariance structure models in the presence of ignorable missing data: the lack of an asymptotically chi-square distributed goodness-of-fit statistic. We show that the Supplemented EM algorithm provides a…

Structural Composites With Tuned EM Chirality

DTIC Science & Technology

2014-12-23

photonic   crystals .   Tammuz  Dubnov  (7/14  –  9/14)  –  Laboratory  Assistant  -­‐  assisted in the testing...AFRL-OSR-VA-TR-2015-0018 STRUCTURAL COMPOSITES WITH TUNED EM CHIRALITY Siavouche Nemat Nasser UNIVERSITY OF CALIFORNIA SAN DIEGO Final Report 12/23...REPORT Grant/Contract  Title:        STRUCTURAL  COMPOSITES  WITH  TUNED  EM   CHIRALITY     Grant  No.:

Newsroom

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from Air Force Gen. Lori Robinson during a ceremony held at Peterson Air Force Base today. May 24, 2018 Gen. O'Shaughnessy assumes command of NORAD, USNORTHCOM Peterson Air Force Base, Colo. - Air Force Gen terminal Sept. 22, 2017 at Joint Base San Antonio-Kelly Field. The cargo was being staged at the Federal

Defense.gov - Dignity, Honor, Respect - For the Fallen

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combat operation passes through Dover Air Force Base, Del. The responsibility, and honor, of preparing Operations Center. Stories Dignified Transfer Pays Tribute to Fallen DOVER AIR FORCE BASE, Del., March 12 vehicle to the Air Force Mortuary Affairs Operations Center at Dover Air Force Base, Del. Story Center

Defense Threat Reduction Agency > About > Locations

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Air Force Base, Ca. Mercury, Nev. Albuquerque, N.M. White Sands Missile Range, N.M. Omaha, Neb . (USSTRATCOM) Eglin Air Force Base, Fla. National Capital Region Georgia Azerbaijan Armenia Japan Republic of , Md. Eglin Air Force Base, Fla. Albuquerque, N.M. White Sands Missile Range, N.M. Mercury, Nev. Travis

Travels With Mullen: Troop Outreach

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. Story Mullen: U.S. Troops 'Best Military' Ever JOINT BASE CHARLESTON, S.C., June 4, 2010 - Chairman of . military members worldwide during a visit with troops and families at Joint Base Charleston, S.C. Story such capabilities into today's military. Story Airmen awarded Bronze Star by CJCS JOINT BASE CHARLESTON

Alternative Fuels Data Center

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must reduce petroleum-based fuel consumption on a per vehicle basis and across the fleet. For non reduction in petroleum-based fuel consumption by 15% (or 7.5% for exempt vehicles) by FY 2020. The Colorado Department of Personnel and Administration may consider certain vehicles to be exempt based on agency

FOLD-EM: automated fold recognition in medium- and low-resolution (4-15 Å) electron density maps.

PubMed

Saha, Mitul; Morais, Marc C

2012-12-15

Owing to the size and complexity of large multi-component biological assemblies, the most tractable approach to determining their atomic structure is often to fit high-resolution radiographic or nuclear magnetic resonance structures of isolated components into lower resolution electron density maps of the larger assembly obtained using cryo-electron microscopy (cryo-EM). This hybrid approach to structure determination requires that an atomic resolution structure of each component, or a suitable homolog, is available. If neither is available, then the amount of structural information regarding that component is limited by the resolution of the cryo-EM map. However, even if a suitable homolog cannot be identified using sequence analysis, a search for structural homologs should still be performed because structural homology often persists throughout evolution even when sequence homology is undetectable, As macromolecules can often be described as a collection of independently folded domains, one way of searching for structural homologs would be to systematically fit representative domain structures from a protein domain database into the medium/low resolution cryo-EM map and return the best fits. Taken together, the best fitting non-overlapping structures would constitute a 'mosaic' backbone model of the assembly that could aid map interpretation and illuminate biological function. Using the computational principles of the Scale-Invariant Feature Transform (SIFT), we have developed FOLD-EM-a computational tool that can identify folded macromolecular domains in medium to low resolution (4-15 Å) electron density maps and return a model of the constituent polypeptides in a fully automated fashion. As a by-product, FOLD-EM can also do flexible multi-domain fitting that may provide insight into conformational changes that occur in macromolecular assemblies.

The impact of recent improvements in cryo-electron microscopy technology on the understanding of bacterial ribosome assembly

PubMed Central

Razi, Aida; Britton, Robert A.

2017-01-01

Abstract Cryo-electron microscopy (cryo-EM) had played a central role in the study of ribosome structure and the process of translation in bacteria since the development of this technique in the mid 1980s. Until recently cryo-EM structures were limited to ∼10 Å in the best cases. However, the recent advent of direct electron detectors has greatly improved the resolution of cryo-EM structures to the point where atomic resolution is now achievable. This improved resolution will allow cryo-EM to make groundbreaking contributions in essential aspects of ribosome biology, including the assembly process. In this review, we summarize important insights that cryo-EM, in combination with chemical and genetic approaches, has already brought to our current understanding of the ribosomal assembly process in bacteria using previous detector technology. More importantly, we discuss how the higher resolution structures now attainable with direct electron detectors can be leveraged to propose precise testable models regarding this process. These structures will provide an effective platform to develop new antibiotics that target this fundamental cellular process. PMID:28180306

Earth Orientation - Naval Oceanography Portal

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section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation USNO Logo USNO Navigation Earth Orientation Products GPS -based Products VLBI-based Products EO Information Center Publications about Products Software Info Earth

EO Information Center - Naval Oceanography Portal

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are here: Home › USNO › Earth Orientation › EO Information Center USNO Logo USNO Navigation Earth Orientation Products GPS-based Products VLBI-based Products EO Information Center General Information GPS User Information Frequently Asked Questions Read Me Files Publications about Products Software

ARCHITECTURE AS PEDAGOGY: INTERDISCIPLINARY DESIGN AND CREATION OF A CARBON NEUTRAL IDAHO ENVIRONMENTAL LEARNING CENTER AT THE UNIVERSITY OF IDAHO MCCALL FIELD CAMPUS

EPA Science Inventory

Output 1. (short-term) Design a carbon neutral field campus with the following design components: structural systems, building envelope, environmental systems, site construction, building materials, information technology, spatial systems and integration ...

Nicholas Steno (1638 1686) compiled a notebook in 1659 when he was a student at the University of Copenhagen. Titled Chaos by Steno, it remains unstudied in English-speaking countries, despite having been translated in 1997. Chaos adds important insight into geology's place in the Scientific Revolution. It shows Steno disengaging from speculations about the cosmos based on the ruling paradigms of Aristotelian metaphysics and Cartesian misconceptions in favor of an empirical model based on the new mathematics of geometry applied to all of nature, from what we now would consider the atomic level, to the human body, and to the planet. Steno thereby earns heretofore unacknowledged credit for helping to establish the geometric definition of form that makes it possible to understand the evolution of the structure of organisms as well as of the planet.

Module 1: Text Versions | State, Local, and Tribal Governments | NREL

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U.S., cities are setting different types of renewable energy goals based on different priorities. Air will talk about different types of goals for renewable energy development, and the importance of , you'll be able to understand the nuances between different types of goals, the importance of terminology

Wind Resource Assessment | Wind | NREL

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Resource Assessment Wind Resource Assessment A map of the United States is color-coded to indicate the high winds at 80 meters. This map shows the wind resource at 80 meters for both land-based and offshore wind resources in the United States. Correct estimation of the energy available in the wind can

Software Tools for Development on the Peregrine System | High-Performance

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Computing | NREL Software Tools for Development on the Peregrine System Software Tools for and manage software at the source code level. Cross-Platform Make and SCons The "Cross-Platform Make" (CMake) package is from Kitware, and SCons is a modern software build tool based on Python

Work Planning and Control - Activity-Based Work Authorization

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Good Activity Description Training & Resources WPC Feedback or Help Request DOE and UC Seals DOE UC Home Training FAQ Contact Home Welcome! The purpose of this site is to keep everyone at LBNL connected in the(Training section). Work Planning and Control (WPC) is a program focused on implementing

Alternative Fuels Data Center: Wisconsin Transportation Data for

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Compressed Natural Gas (CNG) 41 15 Electric 249 36 Ethanol (E85) 189 1 Hydrogen 0 0 Liquefied Natural Gas Natural Gas Electricity Transportation Fuel Consumption Source: State Energy Data System based on beta ) 68,820 Natural Gas (million cubic feet) 400,877 Conventional Power Plants 76 Generating Capacity

Microsoft Licenses Berkeley Lab's Home Energy Saver Code for Its Energy

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-based tool for calculating energy use in residential buildings. About one million people visit the Home Management Software | Berkeley Lab Berkeley Lab A-Z Index Directory Submit Web People Navigation Berkeley Lab Search Submit Web People Close About the Lab Leadership/Organization Calendar News

NREL Supports Effort to Take Distributed Photovoltaics to Developing

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Photovoltaics to Developing Countries NREL Supports Effort to Take Distributed Photovoltaics to Developing project based not only on its demand for renewable energy but also on its need. Pilot projects are adding renewable energy to the grid. Also many developing countries have signed on to the Paris climate

University of Maryland MRSEC - Research: Seed 2

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Administration Committees Directory Research IRG 1 IRG 2 Seed 1 Seed 2 Seed 3 Highlights Publications Facilities MRSEC Templates Opportunities Search Home » Research » Seed 2 Seed 2: Synthesis and Exploration of Topological Insulators Figure 1 High quality single crystals of bismuth-based topological insulator grown at

Iowa | Midmarket Solar Policies in the United States | Solar Research |

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2017, the Iowa Utilities Board approved a pilot program, introduced by Interstate Power and Light, in NRELA> Iowa Iowa An arrow graphic shows that Iowa has 105 MW renewable portfolio standard. Carve Law was adopted in 1983, establishing a capacity-based requirement with no mandated increases

2004-2006 Puget Sound Traffic Choices Study | Transportation Secure Data

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Center | NREL 04-2006 Puget Sound Traffic Choices Study 2004-2006 Puget Sound Traffic Choices Study The 2004-2006 Puget Sound Traffic Choices Study tested the hypothesis that time-of-day variable Administration for a pilot project on congestion-based tolling. Methodology To test the hypothesis, the study

Alternative Fuels Data Center

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Plug-In Electric Vehicle (PEV) Charging Rates - Indianapolis Power & Light The Indianapolis Power & Light Co (IPL) offers special PEV charging rates, including year-round time-of-use based & Light Company Phone: (317) 261-5178 electric.vehicle@aes.com

CBB Portal @ PNNL

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Search PNNL Home About Research Publications Jobs News Contacts Computational Biology and Bioinformatics , and engineering to transform the data into knowledge. This new quantitative, predictive biology is to empirical modeling and physics-based simulations. CBB research seeks to: Understand. Understanding

ACHP | News

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Great Benefits for Nation's Communities WASHINGTON, D.C. - Leading national experts discussed how American Historic Places: Breathing New Life into Our Communities," the session highlighted how a and how historic preservation offers a locally based, grassroots opportunity to improve the nation's

ACHP | Section 3

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the management of federally owned historic properties, the EO encouraged agencies to manage these development. Agencies have approached their oversight and management of historic properties differently based upon budgetary, program, and management considerations. Many agencies have made the preservation and

FOIA Home

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Information Access Policy & Compliance BranchInformation Access Policy & Compliance Branch Join the Air Force Home Offices By Command By Base Library Handbook Annual Reports Resources Privacy Act Search Information Access Policy & Compliance Branch

Alternative Fuels Data Center: Ethanol Production

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States is produced from starch-based crops by dry- or wet-mill processing. Nearly 90% of ethanol plants are dry mills due to lower capital costs. Dry-milling is a process that grinds corn into flour and

Nick Grue | NREL

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geospatial data analysis using parallel processing High performance computing Renewable resource technical potential and supply curve analysis Spatial database utilization Rapid analysis of large geospatial datasets energy and geospatial analysis products Research Interests Rapid, web-based renewable resource analysis

Sustainable Mobility | Transportation Research | NREL

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both safety and energy efficiency. Sustainable Mobility Initiative Takes Systems-Based Approach to of its Sustainable Mobility Initiative, approaching sustainable transportation as an intelligent Transportation Sector Initiative and DOE's Transportation Energy Futures project identify emerging and disruptive

Finding elementary flux modes in metabolic networks based on flux balance analysis and flux coupling analysis: application to the analysis of Escherichia coli metabolism.

PubMed

Tabe-Bordbar, Shayan; Marashi, Sayed-Amir

2013-12-01

Elementary modes (EMs) are steady-state metabolic flux vectors with minimal set of active reactions. Each EM corresponds to a metabolic pathway. Therefore, studying EMs is helpful for analyzing the production of biotechnologically important metabolites. However, memory requirements for computing EMs may hamper their applicability as, in most genome-scale metabolic models, no EM can be computed due to running out of memory. In this study, we present a method for computing randomly sampled EMs. In this approach, a network reduction algorithm is used for EM computation, which is based on flux balance-based methods. We show that this approach can be used to recover the EMs in the medium- and genome-scale metabolic network models, while the EMs are sampled in an unbiased way. The applicability of such results is shown by computing “estimated” control-effective flux values in Escherichia coli metabolic network.

Developing 3D SEM in a broad biological context

PubMed Central

Kremer, A; Lippens, S; Bartunkova, S; Asselbergh, B; Blanpain, C; Fendrych, M; Goossens, A; Holt, M; Janssens, S; Krols, M; Larsimont, J-C; Mc Guire, C; Nowack, MK; Saelens, X; Schertel, A; Schepens, B; Slezak, M; Timmerman, V; Theunis, C; Van Brempt, R; Visser, Y; GuÉRin, CJ

2015-01-01

When electron microscopy (EM) was introduced in the 1930s it gave scientists their first look into the nanoworld of cells. Over the last 80 years EM has vastly increased our understanding of the complex cellular structures that underlie the diverse functions that cells need to maintain life. One drawback that has been difficult to overcome was the inherent lack of volume information, mainly due to the limit on the thickness of sections that could be viewed in a transmission electron microscope (TEM). For many years scientists struggled to achieve three-dimensional (3D) EM using serial section reconstructions, TEM tomography, and scanning EM (SEM) techniques such as freeze-fracture. Although each technique yielded some special information, they required a significant amount of time and specialist expertise to obtain even a very small 3D EM dataset. Almost 20 years ago scientists began to exploit SEMs to image blocks of embedded tissues and perform serial sectioning of these tissues inside the SEM chamber. Using first focused ion beams (FIB) and subsequently robotic ultramicrotomes (serial block-face, SBF-SEM) microscopists were able to collect large volumes of 3D EM information at resolutions that could address many important biological questions, and do so in an efficient manner. We present here some examples of 3D EM taken from the many diverse specimens that have been imaged in our core facility. We propose that the next major step forward will be to efficiently correlate functional information obtained using light microscopy (LM) with 3D EM datasets to more completely investigate the important links between cell structures and their functions. Lay Description Life happens in three dimensions. For many years, first light, and then EM struggled to image the smallest parts of cells in 3D. With recent advances in technology and corresponding improvements in computing, scientists can now see the 3D world of the cell at the nanoscale. In this paper we present the results of high resolution 3D imaging in a number of diverse cells and tissues from multiple species. 3D reconstructions of cell structures often revealed them to be significantly more complex when compared to extrapolations made from 2D studies. Correlating functional 3D LM studies with 3D EM results opens up the possibility of making new strides in our understanding of how cell structure is connected to cell function. PMID:25623622

Relationships among Safety Climate, Safety Behavior, and Safety Outcomes for Ethnic Minority Construction Workers

PubMed Central

Lyu, Sainan; Chan, Albert P. C.; Wong, Francis K. W.

2018-01-01

In many countries, it is common practice to attract and employ ethnic minority (EM) or migrant workers in the construction industry. This primarily occurs in order to alleviate the labor shortage caused by an aging workforce with a lack of new entrants. Statistics show that EM construction workers are more likely to have occupational fatal and nonfatal injuries than their local counterparts; however, the mechanism underlying accidents and injuries in this vulnerable population has been rarely examined. This study aims to investigate relationships among safety climate, safety behavior, and safety outcomes for EM construction workers. To this end, a theoretical research model was developed based on a comprehensive review of the current literature. In total, 289 valid questionnaires were collected face-to-face from 223 Nepalese construction workers and 56 Pakistani construction workers working on 15 construction sites in Hong Kong. Structural equation modelling was employed to validate the constructs and test the hypothesized model. Results show that there were significant positive relationships between safety climate and safety behaviors, and significant negative relationships between safety behaviors and safety outcomes for EM construction workers. This research contributes to the literature regarding EM workers by providing empirical evidence of the mechanisms by which safety climate affects safety behaviors and outcomes. It also provides insights in order to help the key stakeholders formulate safety strategies for EM workers in many areas where numerous EM workers are employed, such as in the U.S., the UK, Australia, Singapore, Malaysia, and the Middle East. PMID:29522503

Distributions of ectomycorrhizal and foliar endophytic fungal communities associated with Pinus ponderosa along a spatially constrained elevation gradient.

PubMed

Bowman, Elizabeth A; Arnold, A Elizabeth

2018-04-01

Understanding distributions of plant-symbiotic fungi is important for projecting responses to environmental change. Many coniferous trees host ectomycorrhizal fungi (EM) in association with roots and foliar endophytic fungi (FE) in leaves. We examined how EM and FE associated with Pinus ponderosa each vary in abundance, diversity, and community structure over a spatially constrained elevation gradient that traverses four plant communities, 4°C in mean annual temperature, and 15 cm in mean annual precipitation. We sampled 63 individuals of Pinus ponderosa in 10 sites along a 635 m elevation gradient that encompassed a geographic distance of 9.8 km. We used standard methods to characterize each fungal group (amplified and sequenced EM from root tips; isolated and sequenced FE from leaves). Abundance and diversity of EM were similar across sites, but community composition and distributions of the most common EM differed with elevation (i.e., with climate, soil chemistry, and plant communities). Abundance and composition of FE did not differ with elevation, but diversity peaked in mid-to-high elevations. Our results suggest relatively tight linkages between EM and climate, soil chemistry, and plant communities. That FE appear less linked with these factors may speak to limitations of a culture-based approach, but more likely reflects the small spatial scale encompassed by our study. Future work should consider comparable methods for characterizing these functional groups, and additional transects to understand relationships of EM and FE to environmental factors that are likely to shift as a function of climate change. © 2018 Botanical Society of America.